WorldWideScience

Sample records for actor network theory

  1. Games as Actors - Interaction, Play, Design, and Actor Network Theory

    DEFF Research Database (Denmark)

    Jessen, Jari Due; Jessen, Carsten

    2014-01-01

    When interacting with computer games, users are forced to follow the rules of the game in return for the excitement, joy, fun, or other pursued experiences. In this paper, we investigate how games a chieve these experiences in the perspective of Actor Network Theory (ANT). Based on a qualitative......, and by doing so they create in humans what in modern play theory is known as a “state of play”...

  2. Consumer culture theory (re)visits actor-network theory

    DEFF Research Database (Denmark)

    Bajde, Domen

    2013-01-01

    The vocabulary and tactics developed by actor-network theory (ANT) can shed light on several ontological and epistemological challenges faced by consumer culture theory. Rather than providing ready-made theories or methods, our translation of ANT puts forward a series of questions and propositions...

  3. Actor/Actant-Network Theory as Emerging Methodology for ...

    African Journals Online (AJOL)

    4carolinebell@gmail.com

    2005-01-31

    Jan 31, 2005 ... to trace relationships, actors, actants and actor/actant-networks .... associated with a particular type of social theory (Latour, 1987; ..... the Department of Environmental Affairs and Tourism, Organised Business and Organised.

  4. Using actor-network theory to study an educational situation: an ...

    African Journals Online (AJOL)

    Actor-network theory allows a researcher to analyse a complex social setting involving both human and non-human actors. An actor network can be used to model a dynamic and complex set of relationships between these actors. This article describes actor-network theory and shows how it was applied to study and model ...

  5. Wave Energy and Actor-Network Theory: The Irish Case

    OpenAIRE

    Cunningham, William

    2013-01-01

    This paper examines the role of the wave energy sector in Ireland using theories from the field of Science and Technology Studies (STS). Theoretical divisions within the field of STS are examined, particularly the Sociology of Scientific Knowledge (SSK) and Actor-Network Theory (ANT). Any conflicts which these two theories present to each other are examined through the empirical findings of the Irish wave energy sector. In particular, ANT s rejection of macro and micro distinctions when analy...

  6. Actor-Network Theory and Tourism : Ordering, materiality and multiplicity

    NARCIS (Netherlands)

    Duim, van der V.R.; Ren, C.; Jóhannesson, G.T.

    2012-01-01

    The recent surfacing of actor-network theory (ANT) in tourism studies correlates to a rising interest in understanding tourism as emergent thorough relational practice connecting cultures, natures and technologies in multifarious ways. Despite the widespread application of ANT across the social

  7. Effects of Actor-Network Theory in Accounting Research

    DEFF Research Database (Denmark)

    Justesen, Lise Nederland; Mouritsen, Jan

    2011-01-01

    Purpose – This paper aims to discuss how Bruno Latour's version of actor-network theory has influenced accounting research. It also seeks to show that Latour's writings contain unexplored potential that may inspire future accounting research. Design/methodology/approach – The paper takes the form...

  8. Actor/Actant-Network Theory as Emerging Methodology for ...

    African Journals Online (AJOL)

    This paper deliberates on actor/actant-network theory (AANT) as methodology for policy research in environmental education (EE). Insights are drawn from work that applied AANT to research environmental policy processes surrounding the formulation and implementation of South Africa's Plastic Bags Regulations of 2003.

  9. Searching for realism, structure and agency in Actor Network Theory.

    Science.gov (United States)

    Elder-Vass, Dave

    2008-09-01

    Superficially, Actor Network Theory (ANT) and critical realism (CR) are radically opposed research traditions. Written from a realist perspective, this paper asks whether there might be a basis for finding common ground between these two traditions. It looks in turn at the questions of realism, structure, and agency, analysing the differences between the two perspectives and seeking to identify what each might learn from the other. Overall, the paper argues that there is a great deal that realists can learn from actor network theory; yet ANT remains stunted by its lack of a depth ontology. It fails to recognize the significance of mechanisms, and of their dependence on emergence, and thus lacks both dimensions of the depth that is characteristic of critical realism's ontology. This prevents ANT from recognizing the role and powers of social structure; but on the other hand, realists would do well to heed ANT's call for us to trace the connections through which structures are constantly made and remade. A lack of ontological depth also underpins ANT's practice of treating human and non-human actors symmetrically, yet this remains a valuable provocation to sociologists who neglect non-human entities entirely.

  10. Actor-network Theory and cartography of controversies in Information Science

    OpenAIRE

    LOURENÇO, Ramon Fernandes; TOMAÉL, Maria Inês

    2018-01-01

    Abstract The present study aims to discuss the interactions between the Actor-network Theory and the Cartography of Controversies method in Information Science research. A literature review was conducted on books, scholarly articles, and any other sources addressing the Theory-Actor Network and Cartography of Controversies. The understanding of the theoretical assumptions that guide the Network-Actor Theory allows examining important aspects to Information Science research, seeking to identif...

  11. Actor Network Theory Approach and its Application in Investigating Agricultural Climate Information System

    Directory of Open Access Journals (Sweden)

    Maryam Sharifzadeh

    2013-03-01

    Full Text Available Actor network theory as a qualitative approach to study complex social factors and process of socio-technical interaction provides new concepts and ideas to understand socio-technical nature of information systems. From the actor network theory viewpoint, agricultural climate information system is a network consisting of actors, actions and information related processes (production, transformation, storage, retrieval, integration, diffusion and utilization, control and management, and system mechanisms (interfaces and networks. Analysis of such systemsembody the identification of basic components and structure of the system (nodes –thedifferent sources of information production, extension, and users, and the understanding of how successfully the system works (interaction and links – in order to promote climate knowledge content and improve system performance to reach agricultural development. The present research attempted to introduce actor network theory as research framework based on network view of agricultural climate information system.

  12. Think about and intervene in the territory through the Actor Network Theory Pensar e intervenir el territorio a traves de la Teoria del Actor-Red

    Directory of Open Access Journals (Sweden)

    Juan E. Cabrera

    2011-03-01

    Full Text Available The purpose of this article is to think about the similarities between the ways of seeing the territory as a network, some theoretical positions about the territory concept and actor network theory.
    After focusing on proposing a way of understanding the relationships between actors when they will intervene in the territory through the public policies and territorial planning, i ll try to apply the ANT model of public policy management through the guidance of ANT El propósito de este artículo es reflexionar sobre las coincidencias entre la forma de ver el territorio como red, algunas posturas teóricas sobre su concepto y la teoría del actor-red.
    Sobre lo anterior se centra en proponer una forma de entender las relaciones entre actores cuando se va a intervenir el territorio a través de políticas públicas como la planificación utilizando un modelo de gestión territorial a través de las orientaciones de la TAR.   

  13. Putting Gino's lesson to work: Actor-network theory, enacted humanity, and rehabilitation.

    Science.gov (United States)

    Abrams, Thomas; Gibson, Barbara E

    2016-02-01

    This article argues that rehabilitation enacts a particular understanding of "the human" throughout therapeutic assessment and treatment. Following Michel Callon and Vololona Rabeharisoa's "Gino's Lesson on Humanity," we suggest that this is not simply a top-down process, but is cultivated in the application and response to biomedical frameworks of human ability, competence, and responsibility. The emergence of the human is at once a materially contingent, moral, and interpersonal process. We begin the article by outlining the basics of the actor-network theory that underpins "Gino's Lesson on Humanity." Next, we elucidate its central thesis regarding how disabled personhood emerges through actor-network interactions. Section "Learning Gino's lesson" draws on two autobiographical examples, examining the emergence of humanity through rehabilitation, particularly assessment measures and the responses to them. We conclude by thinking about how rehabilitation and actor-network theory might take this lesson on humanity seriously. © The Author(s) 2016.

  14. Theorising big IT programmes in healthcare: strong structuration theory meets actor-network theory.

    Science.gov (United States)

    Greenhalgh, Trisha; Stones, Rob

    2010-05-01

    The UK National Health Service is grappling with various large and controversial IT programmes. We sought to develop a sharper theoretical perspective on the question "What happens - at macro-, meso- and micro-level - when government tries to modernise a health service with the help of big IT?" Using examples from data fragments at the micro-level of clinical work, we considered how structuration theory and actor-network theory (ANT) might be combined to inform empirical investigation. Giddens (1984) argued that social structures and human agency are recursively linked and co-evolve. ANT studies the relationships that link people and technologies in dynamic networks. It considers how discourses become inscribed in data structures and decision models of software, making certain network relations irreversible. Stones' (2005) strong structuration theory (SST) is a refinement of Giddens' work, systematically concerned with empirical research. It views human agents as linked in dynamic networks of position-practices. A quadripartite approcach considers [a] external social structures (conditions for action); [b] internal social structures (agents' capabilities and what they 'know' about the social world); [c] active agency and actions and [d] outcomes as they feed back on the position-practice network. In contrast to early structuration theory and ANT, SST insists on disciplined conceptual methodology and linking this with empirical evidence. In this paper, we adapt SST for the study of technology programmes, integrating elements from material interactionism and ANT. We argue, for example, that the position-practice network can be a socio-technical one in which technologies in conjunction with humans can be studied as 'actants'. Human agents, with their complex socio-cultural frames, are required to instantiate technology in social practices. Structurally relevant properties inscribed and embedded in technological artefacts constrain and enable human agency. The fortunes

  15. Actor-network-theory perspective on a forestry decision support system design

    NARCIS (Netherlands)

    Boerboom, L.G.J.; Ferritti, V.

    2014-01-01

    Use of decision support systems (DSS) has thus far been framed as a social process of adoption or technical process of usability. We analyze the development of a DSS as a process of institutionalization of new as well as drift of existing practices. We write an Actor-Network-Theory (ANT) account,

  16. Actor networks in strategic niche management : insights from social network theory

    NARCIS (Netherlands)

    Caniëls, M.C.J.; Romijn, H.A.

    2008-01-01

    This paper contributes to Strategic Niche Management (SNM), an analytical technique designed to facilitate the introduction and diffusion of radically new sustainable technologies through societal experiments. According to SNM, intensive networking among social actors is a crucial process for the

  17. The gender of science: reflections on the actor-network theory and the feminist perspective

    Directory of Open Access Journals (Sweden)

    Gabriel Pugliese Cardoso

    2015-06-01

    Full Text Available This article discusses some of the principles that guide the descriptive forms of the actor-network theory (ANT of Bruno Latour and feminist standpoint theory formulated by Sandra Harding and Evelyn Fox Keller, through my research on the "Marie Curie Case". As a singular case between gender and science, the goal of thispaper is to play with ANT certainties against feminist perspective uncertainties. In the other hand, the certainties of feminist perspective are put against the uncertainties of ANT. With this counterpoint we intend to promote a reaction - in the chemical sense of the word – to the descriptive forms of the actor-network theory and feminist perspective taking away the obviousness of some of their assumptions. Doing that, we explore the moves of those reactions and their effects to the description which we do about science.

  18. Actor-Network Procedures

    NARCIS (Netherlands)

    Pavlovic, Dusko; Meadows, Catherine; Ramanujam, R.; Ramaswamy, Srini

    2012-01-01

    In this paper we propose actor-networks as a formal model of computation in heterogenous networks of computers, humans and their devices, where these new procedures run; and we introduce Procedure Derivation Logic (PDL) as a framework for reasoning about security in actor-networks, as an extension

  19. American Long-Distance Locomobility and the Spaces of Actor-Network Theory

    Directory of Open Access Journals (Sweden)

    Michael Minn

    2016-03-01

    Full Text Available Much of the discourse surrounding national intercity passenger rail service in the United States revolves around why it has lagged so far behind European and Asian counterparts. However, a more interesting question might be why it has survived despite competition from faster, more nimble transport modes, discriminatory public policy, and the ascension of neoliberal discourse hostile to public endeavor. This paper uses the concept of durability in actor-network theory to offer some insights into how the system has achieved a remarkable but problematic stability, and how that durability relates to an imagined role for national intercity passenger rail in a future of increasingly constrained material resources. This paper also demonstrates the application of actor-network theory (ANT in a way that can serve as a useful introduction to and template for the use of that methodology.

  20. OUTDOOR RECREATION THROUGH THE PRISM OF ACTOR-NETWORK THEORY: CHALLENGES AND PROSPECTS

    Directory of Open Access Journals (Sweden)

    Yohann Rech

    2009-12-01

    Full Text Available Actor-network theory (ANT shows how scientific and technical innovations may take the form of a socio-technical network, by the aggregation of humans and non-humans (Callon, 1986; Latour, 1989. This article reflects on the contributions and limits of ANT to examine a particular object of research presenting regular innovations: the outdoor recreation. Firstly, the integration of non-humans to the analysis (Latour, 2006 is relevant in the study of nature sports because physical entities transform the action and involve specific associations. Then it is a particular epistemological positioning that shakes the dichotomies up and givesimportance to the reflexive activity of actors. Finally, understanding the development of collectives is useful for the study of nature sports. The construction of a social coexistence between different activities (sports activities and other activities strongly questions the political transformation of contemporary democracy, including the establishment of a participatory management.

  1. Exploring agency beyond humans: the compatibility of Actor-Network Theory (ANT and resilience thinking

    Directory of Open Access Journals (Sweden)

    Angga Dwiartama

    2014-09-01

    Full Text Available At first glance, the compatibility of social theory and resilience thinking is not entirely evident, in part because the ontology of the former is rooted in social interactions among human beings rather than ecological process. Despite this difference, resilience thinking engages with particular aspects of social organization that have generated intense debates within social science, namely the role of humans as integral elements of social-ecological systems and the processes through which given social structures (including material relations are either maintained or transformed. Among social theoretical approaches, Actor-Network Theory (ANT is noted for its distinctive approach to these aspects. ANT proposes that human and nonhuman components (both referred to as actants have the same capacity to influence the development of social-ecological systems (represented as actor-networks by enacting relations and enrolling other actors. We explore the notion of agency that is employed in resilience thinking and ANT in order to extend our understandings of human-environment relationships through complementary insights from each approach. The discussion is illustrated by reference to ongoing assessment of resilience as it is experienced and expressed in two distinctive agricultural production systems: Indonesian rice and New Zealand kiwifruit. We conclude by establishing the potential for ANT to provide more profound theoretical conceptualizations of agency, both human and nonhuman, in analyses of social ecological systems.

  2. [A non-classical approach to medical practices: Michel Foucault and Actor-Network Theory].

    Science.gov (United States)

    Bińczyk, E

    2001-01-01

    The text presents an analysis of medical practices stemming from two sources: Michel Foucault's conception and the research of Annemarie Mol and John Law, representatives of a trend known as Actor-Network Theory. Both approaches reveal significant theoretical kinship: they can be successfully consigned to the framework of non-classical sociology of science. I initially refer to the cited conceptions as a version of non-classical sociology of medicine. The identity of non-classical sociology of medicine hinges on the fact that it undermines the possibility of objective definitions of disease, health and body. These are rather approached as variable social and historical phenomena, co-constituted by medical practices. To both Foucault and Mol the main object of interest was not medicine as such, but rather the network of medical practices. Mol and Law sketch a new theoretical perspective for the analysis of medical practices. They attempt to go beyond the dichotomous scheme of thinking about the human body as an object of medical research and the subject of private experience. Research on patients suffering blood-sugar deficiency provide the empirical background for the thesis of Actor-Network Theory representatives. Michel Foucault's conceptions are extremely critical of medical practices. The French researcher describes the processes of 'medicalising' Western society as the emergence of a new type of power. He attempts to sensitise the reader to the ethical dimension of the processes of medicalising society.

  3. Actor-Network Theory and methodology: Just what does it mean to say that nonhumans have agency?

    Science.gov (United States)

    Sayes, Edwin

    2014-02-01

    Actor-Network Theory is a controversial social theory. In no respect is this more so than the role it 'gives' to nonhumans: nonhumans have agency, as Latour provocatively puts it. This article aims to interrogate the multiple layers of this declaration to understand what it means to assert with Actor-Network Theory that nonhumans exercise agency. The article surveys a wide corpus of statements by the position's leading figures and emphasizes the wider methodological framework in which these statements are embedded. With this work done, readers will then be better placed to reject or accept the Actor-Network position - understanding more precisely what exactly it is at stake in this decision.

  4. Opening the black box of quality improvement collaboratives: an Actor-Network theory approach

    Directory of Open Access Journals (Sweden)

    Broer Tineke

    2010-09-01

    Full Text Available Abstract Background Quality improvement collaboratives are often labeled as black boxes because effect studies usually do not describe exactly how the results were obtained. In this article we propose a way of opening such a black box, by taking up a dynamic perspective based on Actor-Network Theory. We thereby analyze how the problematisation process and the measurement practices are constructed. Findings from this analysis may have consequences for future evaluation studies of collaboratives. Methods In an ethnographic design we probed two projects within a larger quality improvement collaborative on long term mental health care and care for the intellectually disabled. Ethnographic observations were made at nine national conferences. Furthermore we conducted six case studies involving participating teams. Additionally, we interviewed the two program leaders of the overall projects. Results In one project the problematisation seemed to undergo a shift of focus away from the one suggested by the project leaders. In the other we observed multiple roles of the measurement instrument used. The instrument did not only measure effects of the improvement actions but also changed these actions and affected the actors involved. Conclusions Effectiveness statistics ideally should be complemented with an analysis of the construction of the collaborative and the improvement practices. Effect studies of collaboratives could benefit from a mixed methods research design that combines quantitative and qualitative methods.

  5. Thinking Management and Leadership within Colleges and Schools Somewhat Differently: A Practice-Based, Actor-Network Theory Perspective

    Science.gov (United States)

    Mulcahy, Dianne; Perillo, Suzanne

    2011-01-01

    This article examines the significance of materiality for management and leadership in education using resources provided by actor-network theory (ANT). Espousing the idea that human interactions are mediated by material objects and that these objects participate in the production of practices, ANT affords thinking management and leadership in a…

  6. Exploring the social without a separate domain for religion: on actor-network theory and religion

    Directory of Open Access Journals (Sweden)

    Peik Ingman

    2012-01-01

    Full Text Available In post-secular societies—after secularisation—it may increasingly be the case that the connecting and structuring of religious matter is done outsidedesignated religious sites and without appointed religious experts. The centres of calculation have changed and so the connections between these are different. The former ways of translation and ordering are transforming into new ones. By exiting the designated sites religious matter has found new freedom with the new associations and inventions in the processes of translation. Less control leads to more heterogeneous agencies and facilitates the mobility of religious materials. This less controlled mobility of religious actants can also produce an apparent increase of religious matter, but this does not necessarily mean the return of religion. In any case, this increased plurality combined with increased mobility calls for perspectives which can recognise novelty, andnot just in comparison with previous states of affairs. Actor-network theory (ANT is about tracing the webs of associations between myriad actants whose collective actions produce what we call ‘society’. Dismissing the notion of ‘the social’ as a kind of ‘stuff ’, ANT insists that sociology should focus on the interactional processes—the circulation of ‘the social’ among human and non-human actants—collectively assembling emerging states of affairs.

  7. Reassembling the Information Technology Innovation Process: An Actor Network Theory Method for Managing the Initiation, Production, and Diffusion of Innovations

    Science.gov (United States)

    Zendejas, Gerardo; Chiasson, Mike

    This paper will propose and explore a method to enhance focal actors' abilities to enroll and control the many social and technical components interacting during the initiation, production, and diffusion of innovations. The reassembling and stabilizing of such components is the challenging goal of the focal actors involved in these processes. To address this possibility, a healthcare project involving the initiation, production, and diffusion of an IT-based innovation will be influenced by the researcher, using concepts from actor network theory (ANT), within an action research methodology (ARM). The experiences using this method, and the nature of enrolment and translation during its use, will highlight if and how ANT can provide a problem-solving method to help assemble the social and technical actants involved in the diffusion of an innovation. Finally, the paper will discuss the challenges and benefits of implementing such methods to attain widespread diffusion.

  8. Rethinking agency and medical adherence technology: applying Actor Network Theory to the case study of Digital Pills.

    Science.gov (United States)

    Hurtado-de-Mendoza, Alejandra; Cabling, Mark L; Sheppard, Vanessa B

    2015-12-01

    Much literature surrounding medical technology and adherence posits that technology is a mechanism for social control. This assumes that the medical establishment can take away patients' agency. Although power relationships and social control can play a key role, medical technology can also serve as an agentive tool to be utilized. We (1) offer the alternative framework of Actor Network Theory to view medical technology, (2) discuss the literature on medication adherence and technology, (3) delve into the ramifications of looking at adherence as a network and (4) use Digital Pills as a case study of dispersed agency. © 2015 John Wiley & Sons Ltd.

  9. Actor-Network Theory as a sociotechnical lens to explore the relationship of nurses and technology in practice: methodological considerations for nursing research.

    Science.gov (United States)

    Booth, Richard G; Andrusyszyn, Mary-Anne; Iwasiw, Carroll; Donelle, Lorie; Compeau, Deborah

    2016-06-01

    Actor-Network Theory is a research lens that has gained popularity in the nursing and health sciences domains. The perspective allows a researcher to describe the interaction of actors (both human and non-human) within networked sociomaterial contexts, including complex practice environments where nurses and health technology operate. This study will describe Actor-Network Theory and provide methodological considerations for researchers who are interested in using this sociotechnical lens within nursing and informatics-related research. Considerations related to technology conceptualization, levels of analysis, and sampling procedures in Actor-Network Theory based research are addressed. Finally, implications for future nursing research within complex environments are highlighted. © 2015 John Wiley & Sons Ltd.

  10. Opening up the solar box: Cultural resource management and actor network theory in solar energy projects in the Mojave Desert

    Science.gov (United States)

    Gorrie, Bryan F.

    This project considers the ways that Actor-Network Theory (ANT) can be brought to bear upon Cultural Resource Management (CRM) practices on renewable energy projects. ANT is a way of making inquiry into scientific knowledge practices and as CRM is intended to preserve environmental, historic, and prehistoric resources, it necessarily involves certain kinds of knowledge generation about regions in which projects are being developed. Because the practice of CRM is complex, involving a range of actors from developers to biologists, native peoples to academics, private landholders to environmental and cultural activists, it is imperative to account for the interests of all stakeholders and to resist devolving into the polemical relations of winners and losers, good and bad participants, or simple situations of right and wrong. This project intends to account for the "matters of concern" of various actors, both primary and secondary, by examining the case study of a single solar installation project in the Mojave Desert. A theoretical description of ANT is provided at the beginning and the concerns of this theory are brought to bear upon the case study project through describing the project, discussing the laws governing CRM on federal lands and in the state of California, and providing the points of view of various interviewees who worked directly or indirectly on various aspects of CRM for the solar project. The creators of ANT claim that it is not a methodology but it does speak to ethnomethodologies in that it insists that there is always something more to learn from inquiring into and describing any given situation. These descriptions avoid generalizations, providing instead various points of entry, from diverse perspectives to the project. There is an invitation to avoid assuming that one knows all there is to know about a given situation and to choose instead to continue investigating and thus give voice to the more obscure, often marginalized, voices in the

  11. Beyond effectuation: Analysing the transformation of business ideas into ventures using actor-network theory"

    DEFF Research Database (Denmark)

    Murdock, Karen; Varnes, Claus Juul

    2018-01-01

    definition of the entrepreneurial endeavour. Originality/value This paper examines how ideas are transformed into business ventures by using the ANT to expand understanding from effectuation theory. This shows that means, for instance, are not given but are co-created by the process of translation....../methodology/approach This study uses a longitudinal case study design. The case provides an overview of a new business’s emergence based on three identified translations, each representing critical junctures in the business’s development. An ethnographic approach is selected, which combines observations with qualitative...... as new humans or non-humans become part of it. Including a resource in the network means simultaneously changing the network. This interactionism shows that what sparks interest or attracts resources to a business idea is not simply an influx of additional resources but is simultaneously a dynamic...

  12. A human resources project implementation. An actor-network theory perspective

    Directory of Open Access Journals (Sweden)

    Gibrán Rivera González

    2012-01-01

    Full Text Available Este artículo tiene dos objetivos principales. Primero, sugerir el uso de la Teoría del Actor-Red (ANT por sus siglas en inglés como una teoría que puede ser utilizada para analizar la implementación de un proyecto de recursos humanos (llamado ModeCo, Modelo de Competencias; y, segundo, proveer un entendimiento inicial sobre algunos de los principales eventos y situaciones que dieron forma al ritmo de la implementación de este proyecto. Este artículo se basa en una investigación cualitativa, la cual toma una perspectiva informada por la Teoría del Actor-Red (Callon, 1986; Latour, 1987; Law, 1992 que es utilizada como mecanismo de entendimiento para describir cómo un proyecto es implementado en una Universidad con múltiples campus en México. En este trabajo se ofrecen, primero, una serie de enunciados que capturan la manera en cómo la Teoría del Actor-Red fue útil para entender el proceso de implementación; y, segundo, se exponen los principales eventos y situaciones que afectaron dicho proceso de implementación. En esta investigación adoptamos un modelo interpretativo (Walsham, 1995; Walsham, 2006, mismo que se vale del uso de una batería de métodos, principalmente el uso de doce entrevistas semiestructuradas con diferentes actores del proyecto, documentos del proyecto y asistencia virtual a reuniones del Comité Directivo de recursos humanos. En términos de análisis nuestra investigación está basada en los principios propuestos por Klein and Myers (1999 para estudios interpretativos.

  13. Illuminating the Dark Side of the Internet with Actor-Network Theory: An Integrative Review of Current Cybercrime Research

    Directory of Open Access Journals (Sweden)

    Rocci Luppicini

    2014-06-01

    Full Text Available Cybercrime is a relatively new area of research within criminology and media studies. The purpose of this paper is to pull together current research scholarship at the intersection of Actor-Network Theory (ANT and cybercrime by addressing the following question: How does ANT apply to cybercrime research? A selective integrative review of cybercrime research utilizing ANT was conducted to examine recent developments and identify trends. The review draws on core research papers that span 2002 to 2013. Findings provided a strong indication of ANT’s role in key areas of current cybercrime, namely, cyber bullying, cyber theft, and cyber terrorism and cyber espionage. More specifically, ANT was applied within cyber criminology research to address complex problems involving human-technological interactions, advance alternative models and theoretical perspectives, compare ANT with existing models and theoretical perspectives, and leverage understanding of network influences on actors. Recommendations are provided to help optimize the application of ANT to cybercrime research and practice. This paper helps advance knowledge at the intersection of ANT and the study of cyber criminology.

  14. Memory and Actor-Network Theory: Mediation in Websites of Estadão and Folha de S. Paulo

    Directory of Open Access Journals (Sweden)

    Allysson Viana Martins

    2013-09-01

    Full Text Available This paper discusses how the ideas that guide the Actor-Network Theory (ANT can be the basis for studies from journalism produced for the internet. We seek to apply the principles of ANT to understand the resource mnemonics uses in web journalism and understand which modalities of mediation characterize these uses. The websites of the Estadão and Folha de S. Paulo formed the corpusto be among the main Brazilian (web newspapers, regarding the trials of the specificities of web journalism. The study was conducted in a typical weekin which there has been no event or event featured so as not to corrupt or emphasize some associations. We realize how much can be misleading to consider the mere presence of memory as an indication of quality or depth content.

  15. Learning about a fish from an ANT: actor network theory and science education in the postgenomic era

    Science.gov (United States)

    Pierce, Clayton

    2015-03-01

    This article uses actor network theory (ANT) to develop a more appropriate model of scientific literacy for students, teachers, and citizens in a society increasingly populated with biotechnological and bioscientific nonhumans. In so doing, I take the recent debate surrounding the first genetically engineered animal food product under review by the FDA, AquaBounty Technologies' AquAdvantage® salmon, as a vehicle for exploring the ways in which the biosciences have fundamentally altered the boundary between nature and culture and thus the way the public understands both. In response to the new challenges of a postgenomic society, I outline three frameworks for using ANT literacies in classroom settings. Each frame, I argue, is foundational to the development of a scientific literacy that can trace and map actors involved in controversies such as the AquAdvantage® salmon. In examining these frames I follow the actor of a salmon through an environmental history lens, the technoscientific literacy operating in AquaBounty's FDA application and the National Academies new science education framework, and finally to a model of democracy rooted in an ethic of the common. The ultimate claim of this article is that until science education (and education in general) can begin to include nonhumans such as the AquAdvantage® salmon as part of a common political framework, students, educators, and community members will continue to be at the mercy of experts and corporate stakeholders for defining the terms in which people heal, feed, and educate themselves now and in the future.

  16. Reseña del blog: Networks & Matters: a blog on Actor-Network Theory and philosophical empirism

    Directory of Open Access Journals (Sweden)

    Jorge Leandro Castillo Sepúlveda

    2010-03-01

    Full Text Available La Teoría del Actor-Red, inscrita en los estudios sociales de la ciencia y la tecnología, constituye una aproximación que ha trascendido el ámbito de las investigaciones sociotécnicas, alcanzando el análisis de las rupturas, formaciones y estabilizaciones de las formas más generales de orden social. Networks & Matters, blog creado por cuatro académicos e investigadores reconocidos en el área, constituye un espacio adecuado para actualizarse en discusiones teóricas en torno a esta teoría y a sus asuntos relacionados. Las posibilidades que brinda el formato para comentar y generar discusiones en torno a las temáticas propuestas y la de establecer vínculos hacia otros sitios  y medios relacionados, se conjugan con la exposición de eventos y de publicaciones, tanto nuevas como clásicas. El estilo prolijo de las notas resulta apropiado para quienes se interesen en el campo de la interacción entre ciencia, tecnología y sociedad, y para quienes se adentren en este.

  17. Exploring the Relational Efforts Making up a Curriculum Concept--An Actor-Network Theory Analysis of the Curriculum Concept of "Children's Interests"

    Science.gov (United States)

    Moberg, Emilie

    2018-01-01

    This paper undertakes an investigation of the "life" of the curriculum concept of "children's interests" in a preschool practice. The concept of "children's interests" plays a vital role in the Swedish preschool curriculum text and in the preschool field. Strongly inspired by Actor-network theory readings, the paper…

  18. From translation to enactment: contributions of the Actor-Network Theory to the processual approach to organizations

    Directory of Open Access Journals (Sweden)

    Patricia Kinast De Camillis

    Full Text Available Abstract In the area of Administration, especially in the Organizational Studies (OS, the Actor-Network Theory (ANT has been regarded as part of a movement that aims to leave the functional emphasis of organization and pursue the study of process and practices of organizing - the processual approach to organizations. However, criticism to the ANT has led some authors to seek to overcome them through analytical twists concerning certain concepts. One of these "twists" involved the concept of translation and the inclusion of the concept of enactment . This article discusses both notions with the aid of two studies developed having these concepts as a basis, in order to indicate that the choice of enactment brings along a processual view different from that observed in translation. The concept of translation addresses the predominant and it emphasizes understanding how networks of relationships and objects become "stable"; in turn, enact works with multiplicity and fluidity, where the process takes precedence over things. Although the proposed term enactment does not seek to directly face all criticism, it contributes so that ANT does not take a neutral or mechanical view in its analyses and descriptions. Enactment has the view of organization as a result and product of continuous process and it allows understanding that this is not just working or not (success or failure, but it concerns the "production" of multiple realities when we conduct research in Administration having the processual approach to organizations as a basis.

  19. Efficient Actor Recovery Paradigm for Wireless Sensor and Actor Networks.

    Science.gov (United States)

    Mahjoub, Reem K; Elleithy, Khaled

    2017-04-14

    The actor nodes are the spine of wireless sensor and actor networks (WSANs) that collaborate to perform a specific task in an unverified and uneven environment. Thus, there is a possibility of high failure rate in such unfriendly scenarios due to several factors such as power consumption of devices, electronic circuit failure, software errors in nodes or physical impairment of the actor nodes and inter-actor connectivity problem. Therefore, it is extremely important to discover the failure of a cut-vertex actor and network-disjoint in order to improve the Quality-of-Service (QoS). In this paper, we propose an Efficient Actor Recovery (EAR) paradigm to guarantee the contention-free traffic-forwarding capacity. The EAR paradigm consists of a Node Monitoring and Critical Node Detection (NMCND) algorithm that monitors the activities of the nodes to determine the critical node. In addition, it replaces the critical node with backup node prior to complete node-failure which helps balancing the network performance. The packets are handled using Network Integration and Message Forwarding (NIMF) algorithm that determines the source of forwarding the packets; either from actor or sensor. This decision-making capability of the algorithm controls the packet forwarding rate to maintain the network for a longer time. Furthermore, for handling the proper routing strategy, Priority-Based Routing for Node Failure Avoidance (PRNFA) algorithm is deployed to decide the priority of the packets to be forwarded based on the significance of information available in the packet. To validate the effectiveness of the proposed EAR paradigm, the proposed algorithms were tested using OMNET++ simulation.

  20. Editorial of the Special Issue on Human-Technology Interaction and Technology Adoption: Exploring Frameworks other than Actor-Network Theory

    DEFF Research Database (Denmark)

    Tanev, Stoyan

    2014-01-01

    Actor-network theory (ANT) has established itself as a valuable resource for the analysis of technology innovation and adoption. One of the main reasons for the success of the Innovation Translation Model (a specific instantiation of ANT) is the fact that it fits very well the emerging dominance...... challenges. This is why in this special issue we have focused on exploring, in parallel to ANT, other approaches that have also proven valuable in studying technology adoption and human-technology interaction. Some of these approaches share significant common ground with ANT. They also diverge in some......, Design in-use, Practice theory, Innovation diffusion, Consumer innovativeness and Activity theory....

  1. Discutindo a aprendizagem sob a perspectiva da teoria ator-rede Discussing learning under actor-network theory perspective

    Directory of Open Access Journals (Sweden)

    Maria de Fátima Aranha de Queiroz e Melo

    2011-04-01

    Full Text Available Neste trabalho, discutimos as aprendizagens como um fenômeno dinâmico e multifacetado, produto de uma série de condições que emergem numa causalidade em redes, tomando o corpo enquanto uma instância mediadora que se afeta como um todo nas interações com o mundo. Apoiamo-nos no conceito de tradução defendido pela Teoria Ator-Rede, buscando seus desdobramentos no campo da Psicologia para entender a construção das identidades como apostas sempre provisórias das mesclas de materialidade e socialidade que vão se processando ao longo das biografias dos humanos. Valemo-nos dos princípios Stengers-Despret, atualizados por Latour, apontando para uma epistemologia política alternativa ao fazer uma reflexão sobre o ensinar, o aprender e construir conhecimento: enquanto um processo necessariamente vinculado e sintonizado com outros; enquanto uma empreitada de riscos que leva em conta, como estratégia de sobrevivência, as recalcitrâncias em humanos e não humanos; que oferece ocasiões para diferir num movimento em que todos os envolvidos se modificam pelos efeitos que causam reciprocamente uns nos outros; enquanto uma prática plural e inclusiva, tendo, finalmente, um mundo comum como o objetivo maior destas construções.In this paper, we pose learning as a dynamic and multifaceted phenomenon, which is the product of a series of conditions emerging from a networking causality, taking body as a mediating instance between subject and the world, affecting reciprocally each other. Based on concept of translation, defended by Actor-Network Theory, we searched their unfolding in Psychology field in order to understand the construction of identities as bets, always temporaries, of materiality and sociality processed mixtures, during human biography lifetime. We used Stengers-Despret principles, brought up to date for Latour, pointing to an alternative political epistemology reflecting on teaching, learning and knowledge construction: while a

  2. Self-Recovering Sensor-Actor Networks

    Directory of Open Access Journals (Sweden)

    Maryam Kamali

    2010-07-01

    Full Text Available Wireless sensor-actor networks are a recent development of wireless networks where both ordinary sensor nodes and more sophisticated and powerful nodes, called actors, are present. In this paper we formalize a recently introduced algorithm that recovers failed actor communication links via the existing sensor infrastructure. We prove via refinement that the recovery is terminating in a finite number of steps and is distributed, thus self-performed by the actors. Most importantly, we prove that the recovery can be done at different levels, via different types of links, such as direct actor links or indirect links between the actors, in the latter case reusing the wireless infrastructure of sensors. This leads to identifying coordination classes, e.g., for delegating the most security sensitive coordination to the direct actor-actor coordination links, the least real-time constrained coordination to indirect links, and the safety critical coordination to both direct actor links and indirect sensor paths between actors. Our formalization is done using the theorem prover in the RODIN platform.

  3. Blowing against the wind-An exploratory application of actor network theory to the analysis of local controversies and participation processes in wind energy

    International Nuclear Information System (INIS)

    Jolivet, Eric; Heiskanen, Eva

    2010-01-01

    This paper analyses the deployment of wind power and the related local controversies using actor-network theory (ANT). ANT provides conceptual instruments for a fine-tuned analysis of the contingencies that condition a project's success or failure by focusing on the micro-decisions that intertwine the material aspects of the technology, the site where it is implemented, the participation process, and the social relations in which they are embedded. By considering controversies as alternative efforts of competing networks of actors to 'frame' the reality and enroll others, ANT sheds light on the complex and political nature of planning a wind farm project, insofar as it consist in aligning material and human behaviours into a predictable scenario. 'Overflows' occur when actors do not conform to expectations, adopt conflicting positions and develop their own interpretations of the project, thus obliging designers to adapt their frames and change their plans. To demonstrate this framework, we apply it to the case of a wind farm project in the South of France, near Albi. Our analysis suggests a new approach to examining wind power projects in terms of the interaction between globally circulating technologies, unique characteristics of the site, the participation process and the social dynamics that emerge when these are combined.

  4. Actor-network theory (ANT: uma tradução para compreender o relacional e o estrutural nas redes interorganizacionais?

    Directory of Open Access Journals (Sweden)

    Jackeline Amantino-de-Andrade

    Full Text Available Este ensaio propõe abordar a actor-network theory na análise relacional de redes interorganizacionais, considerando que outras abordagens apresentam limitações, por sustentarem uma divisão entre estrutura e agência. Para consubstanciar essa proposição, primeiramente, é apresentada uma revisão das abordagens de rede nas ciências sociais e, especificamente, nos estudos organizacionais, procurando demonstrar suas distinções, suas inter-relações e sua comum limitação ao se apoiar no estrutural em detrimento do relacional. Em seguida, é apresentada a actor-network theory, com destaque para sua capacidade de integrar o relacional e o estrutural na compreensão dos fenômenos de ordenação; procurando também se evidenciar as aplicações verificadas no campo dos estudos organizacionais. Finalmente, são consideradas as críticas a essa abordagem, ressaltando a diferença de pressupostos, bem como a sua capacidade de trazer contribuições para questões ainda não completamente respondidas, principalmente, quando considerados os fenômenos interorganizacionais.

  5. Technologies for learning? An actor-network theory critique of ‘affordances' in research on mobile learning

    Directory of Open Access Journals (Sweden)

    Gale Parchoma

    2011-12-01

    Full Text Available How is the link between learner and technology made in mobile learning? Whatis the value of the concept of ‘affordances'? And how does research articulatingthis concept act to position mobile devices as ‘technologies for learning'? Thisliterature review used both unstructured and structured search samples of publishedresearch on mobile learning to critically evaluate the prevalence and influenceof the concept of the affordances of mobile technologies. Actor-networktheory is drawn on as a theoretical lens through which to critically considerhow this concept is articulated, and in particular to explore the way it positionsand controls mobile devices as technologies for learning. Parallels in contemporaryaccounts of mobile learning are drawn with classifications of previous discoursesaround the introduction of computers into schools. An alternativeagenda for mobile learning research is suggested with a focus on authentic andinformal contexts rather than controlled experiments.

  6. Performative studies in the actor-network theory (“technological performativity” in works of G. Kien

    Directory of Open Access Journals (Sweden)

    E A Goryacheva

    2013-12-01

    Full Text Available The article considers some theoretical and methodological prerequisites of shaping the concept of «technological performativity» in the works of modern researcher G. Kien whose approach can be characterized as interdisciplinary. Among the numerous existing preconditions of this concept, the author focuses primarily on G. Austin`s theory of speech acts, as well as G. Butler`s gender studies.

  7. Co-evolution of social networks and continuous actor attributes

    NARCIS (Netherlands)

    Niezink, Nynke M.D.; Snijders, Tom A.B.

    2017-01-01

    Social networks and the attributes of the actors in these networks are not static; they may develop interdependently over time. The stochastic actor-oriented model allows for statistical inference on the mechanisms driving this co-evolution process. In earlier versions of this model, dynamic actor

  8. Visualising Actor Network for Cooperative Systems in Marine Technology

    DEFF Research Database (Denmark)

    Pan, Yushan; Finken, Sisse

    2016-01-01

    Awareness is a concept familiar to specialists within the field of Computer Supported Cooperative Work (CSCW). It is superior for analysing and describing some of the ad hoc work activities that unfold in cooperation. Such informal activities are outside the scope of engineers’ formal models, whi...... that shape computer systems. The aim, thus, is to portray cooperative work in a way that can be valuable for engineers implementing marine technology. We do so by way of presenting a transferring technique (2T) using insights from the CSCW field and Actor Network Theory (ANT)....

  9. Political actors playing games: Theory and experiments

    NARCIS (Netherlands)

    Kamm, A.

    2015-01-01

    Political actors exert enormous influence over our daily lives. Their influence on economic activities cannot be underestimated. Voters determine the distribution of political power, political candidates choose policy platforms that they intend to enact if elected, and legislators bargain to arrive

  10. Using attractiveness model for actors ranking in social media networks.

    Science.gov (United States)

    Qasem, Ziyaad; Jansen, Marc; Hecking, Tobias; Hoppe, H Ulrich

    2017-01-01

    Influential actors detection in social media such as Twitter or Facebook can play a major role in gathering opinions on particular topics, improving the marketing efficiency, predicting the trends, etc. This work aims to extend our formally defined T measure to present a new measure aiming to recognize the actor's influence by the strength of attracting new important actors into a networked community. Therefore, we propose a model of the actor's influence based on the attractiveness of the actor in relation to the number of other attractors with whom he/she has established connections over time. Using an empirically collected social network for the underlying graph, we have applied the above-mentioned measure of influence in order to determine optimal seeds in a simulation of influence maximization. We study our extended measure in the context of information diffusion because this measure is based on a model of actors who attract others to be active members in a community. This corresponds to the idea of the IC simulation model which is used to identify the most important spreaders in a set of actors.

  11. Innovation barriers originating from the differing logics of network actors:

    DEFF Research Database (Denmark)

    Aarikka-Stenroos, Leena; Alaranta, Mar

    2016-01-01

    The recent IMP and innovation network research has highlighted that diverse aspects of actors' heterogeneity such as differing goals, knowledge bases, capabilities and competences, perceptions, power, position, and culture play a role in the development of collaborative innovation....../organization, inter-organizational and ecosystem levels. Our results advance knowledge on the diversity of barriers in collaborative innovation and commercializing science and how they relate to the different actors: a body of knowledge that is increasingly discussed among IMP stream....

  12. Stochastic actor-oriented models for network change

    NARCIS (Netherlands)

    Snijders, T.A.B.

    1996-01-01

    A class of models is proposed for longitudinal network data. These models are along the lines of methodological individualism: actors use heuristics to try to achieve their individual goals, subject to constraints. The current network structure is among these constraints. The models are continuous

  13. Consolidated Deep Actor Critic Networks (DRAFT)

    NARCIS (Netherlands)

    Van der Laan, T.A.

    2015-01-01

    The works [Volodymyr et al. Playing atari with deep reinforcement learning. arXiv preprint arXiv:1312.5602, 2013.] and [Volodymyr et al. Human-level control through deep reinforcement learning. Nature, 518(7540):529–533, 2015.] have demonstrated the power of combining deep neural networks with

  14. Exchange Studies as Actor-Networks: Following Korean Exchange Students in Swedish Higher Education

    Science.gov (United States)

    Ahn, Song-ee

    2011-01-01

    This article explores how Korean exchange students organized their studies during exchange programs in Swedish higher education. For most students, the programs became a disordered period in relation to their education. The value of exchange studies seems mainly to be extra-curricular. Drawing upon actor network theory, the article argues that the…

  15. Extended mind and after: socially extended mind and actor-network.

    Science.gov (United States)

    Kono, Tetsuya

    2014-03-01

    The concept of extended mind has been impressively developed over the last 10 years by many philosophers and cognitive scientists. The extended mind thesis (EM) affirms that the mind is not simply ensconced inside the head, but extends to the whole system of brain-body-environment. Recently, some philosophers and psychologists try to adapt the idea of EM to the domain of social cognition research. Mind is socially extended (SEM). However, EM/SEM theory has problems to analyze the interactions among a subject and its surroundings with opposition, antagonism, or conflict; it also tends to think that the environment surrounding the subject is passive or static, and to neglect the power of non-human actants to direct and regulate the human subject. In these points, actor-network theory (ANT) proposed by Latour and Callon is more persuasive, while sharing some important ideas with EM/SEM theory. Actor-network is a hybrid community which is composed of a series of heterogeneous elements, animate and inanimate for a certain period of time. I shall conclude that EM/SEM could be best analyzed as a special case of actor-network. EM/SEM is a system which can be controlled by a human agent alone. In order to understand collective behavior, philosophy and psychology have to study the actor-network in which human individuals are situated.

  16. Reactors, Weapons, X-Rays, and Solar Panels: Using SCOT, Technological Frame, Epistemic Culture, and Actor Network Theory to Investigate Technology

    Science.gov (United States)

    Sovacool, Benjamin K.

    2006-01-01

    The article explores how four different theories have been used to investigate technology. It highlights the worth and limitations of each theory and argues that an eclectic, ever-evolving approach to the study of technology is warranted. (Contains 1 table.)

  17. E-learning objects and actor-networks as configuring information literacy teaching

    DEFF Research Database (Denmark)

    Schreiber, Trine Louise

    2017-01-01

    Introduction. With actor-network theory (ANT) as the theoretical lens the aim of the paper is to examine attempts to build network for shaping information literacy teaching. Method. The paper is based on a study of a project in 2014-2016 where information professionals representing ten educational...... libraries produced and implemented e-learning objects in information literacy teaching. The material was collected through interviews, observations, documents and feedback sessions. Analysis. Latour´s concept of translation and Callon´s four translation moments are used to analyze the network building...... that a network configuring information literacy teaching based on new interactive roles has not been stabilized. Conclusion. The paper concludes that the strength of ANT is first of all the mediation of an overview of different kinds of actors involved in network building. Further, the paper proposes to combine...

  18. Bruno Latour, actor-networks, and the critique of critical sociology

    Directory of Open Access Journals (Sweden)

    Spasić Ivana

    2007-01-01

    Full Text Available The paper analyzes the theoretical opus of Bruno Latour and his treatment of the concept of critique. In the first section "actor-network theory" is presented through its key notions (actant, network, translation, associations together with Latour’s theory of modernity. In the second section various aspects of the relation between Latour and critique are discussed - first his own criticism of others (standard sociology and especially "critical", i.e. Bourdieu’s sociology, then the criticisms aimed at his work, to conclude with the political ambivalences of Latour’s attempt to develop an "acritical" social theory. .

  19. Trail-Based Search for Efficient Event Report to Mobile Actors in Wireless Sensor and Actor Networks.

    Science.gov (United States)

    Xu, Zhezhuang; Liu, Guanglun; Yan, Haotian; Cheng, Bin; Lin, Feilong

    2017-10-27

    In wireless sensor and actor networks, when an event is detected, the sensor node needs to transmit an event report to inform the actor. Since the actor moves in the network to execute missions, its location is always unavailable to the sensor nodes. A popular solution is the search strategy that can forward the data to a node without its location information. However, most existing works have not considered the mobility of the node, and thus generate significant energy consumption or transmission delay. In this paper, we propose the trail-based search (TS) strategy that takes advantage of actor's mobility to improve the search efficiency. The main idea of TS is that, when the actor moves in the network, it can leave its trail composed of continuous footprints. The search packet with the event report is transmitted in the network to search the actor or its footprints. Once an effective footprint is discovered, the packet will be forwarded along the trail until it is received by the actor. Moreover, we derive the condition to guarantee the trail connectivity, and propose the redundancy reduction scheme based on TS (TS-R) to reduce nontrivial transmission redundancy that is generated by the trail. The theoretical and numerical analysis is provided to prove the efficiency of TS. Compared with the well-known expanding ring search (ERS), TS significantly reduces the energy consumption and search delay.

  20. Trail-Based Search for Efficient Event Report to Mobile Actors in Wireless Sensor and Actor Networks

    Science.gov (United States)

    Xu, Zhezhuang; Liu, Guanglun; Yan, Haotian; Cheng, Bin; Lin, Feilong

    2017-01-01

    In wireless sensor and actor networks, when an event is detected, the sensor node needs to transmit an event report to inform the actor. Since the actor moves in the network to execute missions, its location is always unavailable to the sensor nodes. A popular solution is the search strategy that can forward the data to a node without its location information. However, most existing works have not considered the mobility of the node, and thus generate significant energy consumption or transmission delay. In this paper, we propose the trail-based search (TS) strategy that takes advantage of actor’s mobility to improve the search efficiency. The main idea of TS is that, when the actor moves in the network, it can leave its trail composed of continuous footprints. The search packet with the event report is transmitted in the network to search the actor or its footprints. Once an effective footprint is discovered, the packet will be forwarded along the trail until it is received by the actor. Moreover, we derive the condition to guarantee the trail connectivity, and propose the redundancy reduction scheme based on TS (TS-R) to reduce nontrivial transmission redundancy that is generated by the trail. The theoretical and numerical analysis is provided to prove the efficiency of TS. Compared with the well-known expanding ring search (ERS), TS significantly reduces the energy consumption and search delay. PMID:29077017

  1. The role of actor-networks in the early stage mobilisation of low carbon heat networks

    International Nuclear Information System (INIS)

    Ambrose, Aimee; Eadson, Will; Pinder, James

    2016-01-01

    Low carbon heat networks (LCHNs) offer great potential for carbon and heating cost reduction. Despite these benefits, LCHNs provide for just two per cent of heat demand in the UK, when estimates suggest they have the potential to provide for around 43 per cent. These low levels of LCHN provision are in stark contrast to the Nordic nations which exemplify some of the highest quality and most extensive heat networks in the world. It is within this context that the Pioneer Cities project (the project) was launched by the UK government to help local authorities overcome barriers to the deployment of LCHNs. This paper reports the findings of an evaluation of this project, drawing on 86 interviews across five local authorities, analysed using elements of Actor Network Theory (ANT). The evaluation found that the project’s success has been limited. Participating local authorities have encountered challenges regarding marketisation, public sector retrenchment and inexperience in mobilising LCHNs. These factors militate against the formation of the robust actor-networks required to deploy LCHNs. Analysis using ANT reveals insights into why LCHNs remain elusive in the UK and suggests that policy makers need to strengthen local authorities’ ability to lead and deliver complex infrastructure projects. - Highlights: •Low carbon heat networks (LCHNs) reduce carbon emissions from heat production and reduce costs. •Yet market issues and local government cut backs undermine successful delivery of LCHNs. •Local authorites are charged by government with deploying LCHNS but are not well placed to do so. •Policy makers need to ‘prepare the ground’ for LCHN deployment through policy and incentives.

  2. Cognitively Central Actors and Their Personal Networks in an Energy Efficiency Training Program

    Science.gov (United States)

    Hytönen, Kaisa; Palonen, Tuire; Hakkarainen, Kai

    2014-01-01

    This article aims to examine cognitively central actors and their personal networks in the emerging field of energy efficiency. Cognitively central actors are frequently sought for professional advice by other actors and, therefore, they are positioned in the middle of a social network. They often are important knowledge resources, especially in…

  3. Actor-networking ceta-sociality, or, what is sociological about contemporary whales?

    DEFF Research Database (Denmark)

    Blok, Anders

    2007-01-01

    theory (ANT) allows for the inclusion of non-human ‘actants' (like whales) into the fabric of sociality. In the ontology of ANT, sociality emerges as semiotic-material configurations of humans, animals and technologies. Starting from a critical review of the work by Adrian Franklin on growing......In contemporary urban Euro-American societies, whales have become hugely popular and iconic creatures, arousing controversies more intense than most other instances of animal politics. How to account sociologically, however, for the dramatic social transformation of whales, from natural resource...... to near-sacrosanct agent, is far from self-evident. This article advocates a change of theoretical perspective, inspired by the work of actor-network theorists Bruno Latour and Michel Callon. Rather than focussing solely on the ‘humanity' of human-animal relations, as does most of sociology, actor-network...

  4. Tourism Chains and Pro-Poor Tourism Development: An Actor-Network Analysis of a Pilot Project in Costa Rica

    NARCIS (Netherlands)

    Duim, van der V.R.; Caalders, J.D.A.D.

    2008-01-01

    This paper analyses a pilot project in Costa Rica aimed to examine and improve the market linkages of 24 small-scale tourism initiatives to tour operators in Costa Rica and the Netherlands. It links pro-poor tourism and the concept of tourism chain to actor-network theory. The analysis shows that

  5. Framing labor contracts : Contract versus network theories

    NARCIS (Netherlands)

    Knegt, R.

    2016-01-01

    Since the 18th century the ‘contractual model’ has become both a paradigm of social theories (f.i. ‘rational choice’) and a dominant model of structuring labour relations. Its presupposition of the subjectivity of individual actors as a given is criticized with reference to network-based theories

  6. The Grand Strategy of Nonstate Actors: Theory and Implications

    Directory of Open Access Journals (Sweden)

    Garrett Pierman

    2015-12-01

    Full Text Available This article addresses the Realist assumption that only actors that are states can be considered to have a strategic culture. The primary issue raised is the question of the ability of non-state actors to have a strategic culture. Al-Qaida is used as a theoretical case study. Ultimately this article rejects the idea of territoriality in strategic culture formulation and calls for academics and policymakers alike to adopt a broader conception of actors on the international, stage. This broader conception of actors would necessitate rich case studies to be done in the future in order to seek an understanding of the strategic culture of the non-state actors which academics and policymakers must deal with in the modern security environment. In particular, the article finds that the assumptions held about al-Qaida thus far are wrong and, in reality, the group has ambitions that are cosmic in nature, which will necessitate change in the strategies used to fight against terrorism.

  7. EXTERNALITIES IN EXCHANGE NETWORKS AN ADAPTATION OF EXISTING THEORIES OF EXCHANGE NETWORKS

    NARCIS (Netherlands)

    Dijkstra, Jacob

    2009-01-01

    The present paper extends the focus of network exchange research to externalities in exchange networks. Externalities of exchange are defined as direct effects on an actor's utility, of an exchange in which this actor is not involved. Existing theories in the field of network exchange do not inform

  8. Actor networks and the construction of applicable knowledge: the case of the Timbre Brownfield Prioritization Tool

    Czech Academy of Sciences Publication Activity Database

    Alexandrescu, F.; Klusáček, Petr; Bartke, S.; Osman, Robert; Frantál, Bohumil; Martinát, Stanislav; Kunc, Josef; Pizzol, L.; Zabeo, A.; Giubilato, E.; Critto, A.; Bleicher, A.

    2017-01-01

    Roč. 19, č. 5 (2017), s. 1323-1334 ISSN 1618-954X R&D Projects: GA MŠk(CZ) 7E11035; GA ČR(CZ) GA17-26934S Institutional support: RVO:68145535 Keywords : actor network theory * applicable knowledge * brownfield prioritization * four moments of translation * end-users Subject RIV: DE - Earth Magnetism, Geodesy, Geography OBOR OECD: Environmental sciences (social aspects) Impact factor: 3.331, year: 2016 https://link.springer.com/article/10.1007/s10098-016-1331-8

  9. Actor networks and the construction of applicable knowledge: the case of the Timbre Brownfield Prioritization Tool

    Czech Academy of Sciences Publication Activity Database

    Alexandrescu, F.; Klusáček, Petr; Bartke, S.; Osman, Robert; Frantál, Bohumil; Martinát, Stanislav; Kunc, Josef; Pizzol, L.; Zabeo, A.; Giubilato, E.; Critto, A.; Bleicher, A.

    2017-01-01

    Roč. 19, č. 5 (2017), s. 1323-1334 ISSN 1618-954X R&D Projects: GA MŠk(CZ) 7E11035; GA ČR(CZ) GA17-26934S Institutional support: RVO:68145535 Keywords : actor network theory * applicable knowledge * brownfield prioritization * four moments of translation * end-users Subject RIV: DE - Earth Magnetism, Geodesy, Geography OBOR OECD: Environment al sciences (social aspects) Impact factor: 3.331, year: 2016 https://link.springer.com/article/10.1007/s10098-016-1331-8

  10. Using social network analysis to understand actor participation and ...

    African Journals Online (AJOL)

    Peripheral actors advocate issues of compensation and land grabbing from buffer zone establishment and wetland resources uses for livelihoods, but are unable to influence the central actors's agenda. SNA E-I Index reveals that government organisations are more cohesive and able to form strong ties with donors to ...

  11. Linear network theory

    CERN Document Server

    Sander, K F

    1964-01-01

    Linear Network Theory covers the significant algebraic aspect of network theory, with minimal reference to practical circuits. The book begins the presentation of network analysis with the exposition of networks containing resistances only, and follows it up with a discussion of networks involving inductance and capacity by way of the differential equations. Classification and description of certain networks, equivalent networks, filter circuits, and network functions are also covered. Electrical engineers, technicians, electronics engineers, electricians, and students learning the intricacies

  12. A matter of relationships: Actor-networks of colonial rule in the Gezira irrigation system, Sudan

    Directory of Open Access Journals (Sweden)

    Maurits Ertsen

    2016-06-01

    Full Text Available In the first half of the 20th century, colonial rulers, a British firm and Sudanese farmers changed the Gezira Plain in Sudan into a large-scale irrigated cotton scheme. Gezira continues to be in use up to date. Its story shows how the abstract concept 'development' is shaped through the agency of humans and non-humans alike in government offices and muddy fields. Gezira provides a well-suited starting point for moving into the networks of development without any pre-suggested division in terms of levels, contexts or relations. Hierarchies, arenas and institutions do exist. Such power relations are associations between humans and non-humans: relatively stable relations are typically produced when non-human agency is involved, for example through books, roads, and money. The Gezira case shows the potential of actor-network theory in building and understanding of conceptual and empirical links between water, infrastructure and political rule.

  13. Actor-Network Theory as I image it. Brief essay on traffic lights La ANT tal como yo la imagino. Breve ensayo sobre el cosmos semafórico

    Directory of Open Access Journals (Sweden)

    Carlos Enrique Silva Rios

    2011-03-01

    ="hps">I decided to do my research in Barcelona only. Later on, for studying people crossing the street, I decided to consider traffic lights as a starting point. Then I undertook the task of preparing a field diary based on some of the notions of Actor-Network Theory as Bruno Latour puts them. I did not use Consequences of Strategic Choices within an e-Procurement Implementation Process -From an Actor Network Perspective

    DEFF Research Database (Denmark)

    Krag, Lotte; Thomsen, Mette; Jensen, Tina Blegind

    2004-01-01

    have to be made in order to ensure the success of the implementation in terms of the technical aspects, the business model and the organisation. This article deals with three strategic choices made by the management in the case company, a large European medical company, regarding the process...... of implementing an e-Procurement system - more specifically, an Enterprise Buyer Professional (EBP) module in SAP R/3 for commercial purchasing. These strategic choices are (1) outsourcing the electronic catalogue of the EBP system to an electronic market place, (2) constituting a change management group...... for the implementation, and (3) allying with an external partner in the implementation process. The strategic choices are the basis of a qualitative analysis using an Actor Network Theory (ANT) perspective where focus is on three aspects: Delegation, black box and enrolment. In this regard, strategies for delegating...

  14. Ethics in actor networks, or: what Latour could learn from Darwin and Dewey.

    Science.gov (United States)

    Waelbers, Katinka; Dorstewitz, Philipp

    2014-03-01

    In contemporary Science, Technology and Society (STS) studies, Bruno Latour's Actor Network Theory (ANT) is often used to study how social change arises from interaction between people and technologies. Though Latour's approach is rich in the sense of enabling scholars to appreciate the complexity of many relevant technological, environmental, and social factors in their studies, the approach is poor from an ethical point of view: the doings of things and people are couched in one and the same behaviorist (third person) vocabulary without giving due recognition to the ethical relevance of human intelligence, sympathy and reflection in making responsible choices. This article argues that two other naturalist projects, the non-teleological virtue ethics of Charles Darwin and the pragmatist instrumentalism of John Dewey can enrich ANT-based STS studies, both, in a descriptive and in a normative sense.

  15. Bridging centrality: A new indicator to measure the positioning of actors in R&D networks

    Energy Technology Data Exchange (ETDEWEB)

    Scherngell, T.; Wanzenboeck, I.; Berge, L.

    2016-07-01

    In the recent past, we can observe growing interest in the STI community in the notion of positioning indicators, shifting emphasis to actors in the innovation process and their R&D inter-linkages with other actors. In relation to this, we suggest a new approach for assessing the positioning of actors relying on the notion of bridging centrality (BC). Based on the concept of bridging paths, i.e. a set of two links connecting three actors across three different aggregate nodes (e.g. organisations, regions or countries), we argue that triangulation in networks is a key issue for knowledge recombinations and the extension of an actor's knowledge base. As bridges are most often not empirically observable at the individual level of research teams, we propose an approximated BC measure that provides a flexible framework for dealing with the aggregation problem in positioning actors. Hereby, BC is viewed as a function of an aggregate node's (i) participation intensity in the network, (ii) its openness to other nodes (i.e. the relative outward orientation of network links), and iii) the diversification of links to other nodes. In doing so, we provide an integrative perspective that enables us to achieve a better understanding of the positioning of certain actors in R&D networks. An illustrative example on the co-patent network of European regions demonstrates the performance and usefulness of our BC measure for networks constructed at the aggregated level, i.e. regions in our example. A region's outward orientation and the diversification of its network links moderates the influence of regional scale on network centrality. This is a major strength of the measure, and it paves the way for future studies to examine the role of certain aggregate node's, and, by this, contributes to the debate on positioning indicators in the STI context. (Author)

  16. Competing actors in the climate change arena in Mexico: A network analysis.

    Science.gov (United States)

    Ortega Díaz, Araceli; Gutiérrez, Erika Casamadrid

    2018-06-01

    This paper analyzes the actors in the climate change arena and their influence in directing Mexico toward policies that decrease greenhouse gas emissions, such as the carbon tax and climate change law. The network analysis of the agreement of these laws and public policies in Mexico is a lesson for any country that is in the process of designing and adopting environmental laws. The research is performed using a network analysis that is derived from interviews with various main actors and a discourse analysis of the media. Results show that actors do not coordinate their efforts-they meet frequently but in different inter-ministerial commissions-and do not enforce the same policies. The actors in the industry have formed strong coalitions against the carbon tax and the General Law on Climate Change, whereas international institutions have formed coalitions that support these policies and laws. Copyright © 2018 Elsevier Ltd. All rights reserved.

  17. NAVIGATING PROTOTYPING SPACES FOR CO-DESIGN OF ACTOR-NETWORKS

    DEFF Research Database (Denmark)

    Pedersen, Signe; Brodersen, Søsser

    2017-01-01

    of diverse actors in what we term prototyping spaces. In these prototyping spaces, prototypes play an important role in visualising controversies, enabling matters of concern to be negotiated, and making knowledge transparent throughout the design process. Based on a case study of a pilot program to make...... of temporary prototyping spaces, which are to be staged and facilitated to allow various actors to negotiate matters of concern. Designers then translate the resulting knowledge and insights into pro-totypes for use in subsequent spaces and eventually into an actor-network com-prising the final solution....

  18. Prospect Theory: Contributions to Understanding Actors, Causes and Consequences of Conflict in Africa

    Directory of Open Access Journals (Sweden)

    Wendy Trott

    2013-08-01

    Full Text Available Despite many recognized shortcomings, Rational Choice Theory remains the dominant perspective on decision-making in the literature on African conflict, whether overtly acknowledged or not. Prospect Theory, originally derived from the field of behavioural economics, can complement and advance this perspective not only by explaining the behaviour of actors, but also by allowing for predictions and the devising of strategies to avoid or end on-going conflicts based on a set of systematic biases that influence how actors make decisions. After a brief definition of Prospect Theory, this work will begin with an overview of the existing literature on decision-making as it relates to conflict, examine how Rational Choice is inadequate in explaining much human behaviour and thus how Prospect Theory can fill this gap. It will then move on to give a fuller definition of the various hypotheses derived from Prospect Theory that pertain to the study of conflict. An example of the application of Prospect Theory to a related field in which thorough research has been conducted, Deterrence Theory, will be used to demonstrate the model’s potential for study in other areas. This will be followed by a more in-depth analysis of the ways in which Prospect Theory can contribute to understanding the behaviour of actors in war, the causes of conflict, and the consequences in the African context. It will conclude with a summary and proposition for further research that can advance this analysis.

  19. Labeling Actors and Uncovering Causal Accounts of Their States in Social Networks and Social Media

    Science.gov (United States)

    Bui, Ngot P.

    2016-01-01

    The emergence of social networks and social media has resulted in exponential increase in the amount of data that link diverse types of richly structured digital objects e.g., individuals, articles, images, videos, music, etc. Such data are naturally represented as heterogeneous networks with multiple types of objects e.g., actors, video,…

  1. Report: Information Meeting / Awareness of Actors on the Chemical Information Exchange Network (CIEN)

    International Nuclear Information System (INIS)

    Senghor, Cheikh

    2015-01-01

    As part of the implementation of the Stockholm Convention, Senegal has established a Chemical Information Exchange Network. The overall objective of this meeting was to identify the various actors involved in the management of chemicals information and to study the modalities for the implementation of the chemical information exchange network in Senegal.

  2. International organizations as corporate actors: Agency and emergence in theories of international relations

    OpenAIRE

    Maier-Rigaud, Remi

    2008-01-01

    In this paper, the implicit and explicit conceptualizations of international organizations found in the three major theories of international relations are outlined and compared. It turns out that in a neorealist framework, international organizations can be explained; however, they exhibit no autonomy and cannot therefore be conceptualized as a corporate actor. Principally, the same applies to rational choice institutionalism, although limited autonomy is conceivable. Both theories are reduc...

  3. Following the moving and changing attachments and assemblages of 'addiction': Applying the actor network approach to autobiographies.

    Science.gov (United States)

    Törrönen, Jukka; Tigerstedt, Christoffer

    2018-04-01

    The article applies actor network theory (ANT) to autobiographical data on alcohol dependence to explore what ANT can offer to the analysis of 'addiction stories'. By defining 'addiction' as a relational achievement, as the effect of elements acting together as a configuration of human and non-human actors, the article demonstrates how the moving and changing attachments of addiction can be dynamically analyzed with concepts of 'assemblage', 'mediator', 'tendency', 'translation', 'trajectory', 'immutable mobile', 'fluid' and 'bush fire'. The article shows how the reduction of alcohol dependence simply to genetic factors, neurobiological causes, personality disorders and self-medication constitutes an inadequate explanation. As 'meta theories', they illuminate addiction one-sidedly. Instead, as ANT pays attention to multiple heterogeneous mediators, it specifies in what way the causes identified in 'meta theories' may together with other actors participate in addiction assemblages. When following the development of addiction assemblages, we focus on situational sequences of action, in which human and non-human elements are linked to each other, and we trace how the relational shape of addiction changes from one sequence to another as a transforming assemblage of heterogeneous attachments that either maintain healthy subjectivities or destabilize them. The more attachments assemblages of addiction are able to make that are flexible and durable from one event to another, the stronger also the addiction-based subjectivities. Similarly, the fewer attachments that assemblages of addiction are able to keep in their various translations, the weaker the addiction-based subjectivities also become. An ANT-inspired analysis has a number of implications for the prevention and treatment of addiction: it suggests that in the prevention and treatment of addiction, the aim should hardly be to get rid of dependencies. Rather, the ambition should be the identification of attachments

  4. The Influence of the Actor Network on the Innovative Process of Transgenic Soybean in Rio Grande Do Sul, Brazil

    Directory of Open Access Journals (Sweden)

    Doriana Daroit

    2009-12-01

    Full Text Available Rio Grande do Sul was the first Brazilian state to plant genetically modified soybean. The sowing occurred in 1998 with Roundup Ready soybean seeds from Monsanto smuggled from Argentina. The aim of this study is to investigate how this innovative process of planting transgenic soybean came about in Rio Grande do Sul based on the actor network involved in the period 1998 to 2003. Although the innovative process has been discussed in the literature on innovation management since the work of Schumpeter, there is still no clear understanding of the issues of interests and power that involve the innovative process. Given this, from within the literature we have sought a perspective that would understand the innovative process as being political. We adopted Actor Network Theory as a base for the discussion of the primary and secondary data obtained regarding the controversy surrounding transgenic soybean in RS. The results point to the existence of two translation chains that contribute towards the formation of actor networks.

  5. Low cost drip irrigation in Burkina Faso : unravelling actors, networks and practices

    NARCIS (Netherlands)

    Wanvoeke, M.J.V.

    2015-01-01

    Title: Low cost drip irrigation in Burkina Faso: Unravelling Actors, Networks and Practices

    In Burkina Faso, there is a lot of enthusiasm about Low Cost Drip Irrigation (LCDI) as a tool to irrigate vegetables, and thus improve food security,

  6. Tourism Chains and Pro-Poor Tourism Development: An Actor-Network Analysis of a Pilot Project in Costa Rica

    OpenAIRE

    Duim, van der, V.R.; Caalders, J.D.A.D.

    2008-01-01

    This paper analyses a pilot project in Costa Rica aimed to examine and improve the market linkages of 24 small-scale tourism initiatives to tour operators in Costa Rica and the Netherlands. It links pro-poor tourism and the concept of tourism chain to actor-network theory. The analysis shows that the tangible results in terms of pro-poor tourism of the project itself were meagre, as, initially, only three and later only one out of 24 projects was included in the tourism chain. However, the an...

  7. Teoria de sistemas autopoiéticos y la “actor network theory”: ¿Hacia una convergencia posestructuralista?

    Directory of Open Access Journals (Sweden)

    Josep Pont Vidal

    2016-06-01

    Full Text Available http://dx.doi.org/10.5007/1807-1384.2016v13n2p38 Desde hace unos años se manifiesta un creciente interés entre los sociólogos en establecer un nexo entre la Teoría de sistemas sociales autorreferenciales de Niklas Luhmann con los marcos teóricos que componen la filosofía social posestructuralista. Aunque existe una autodefinición común estructural-funcionalista aparecen insoslayables diferencias entre la teoría sistémica de Luhmann y el constructivismo de la Actor Network Theory.

  8. Mapping industrial systems - a supply network perspective on enabling technologies, processes and actors

    OpenAIRE

    Srai, Jagjit Singh

    2016-01-01

    This is the author accepted manuscript. The final version is available from InderScience Publishers via http://dx.doi.org/10.1504/IJMTM.2017.10002927 This paper develops a multi-layered multi-stage mapping approach to explore the characteristics of emerging industry supply networks (EI SNs), and how enabling production technologies and supply chain processes are supported by institutional, industrial and supply network actors. The mapping methodology involves the systematic capture of mate...

  9. Transitions across place and space – Spatial transitions in an Actor Network perspective

    DEFF Research Database (Denmark)

    Kerndrup, Søren; Mosgaard, Mette

    2012-01-01

    , that interactions and relations in these networks in spite of their focus on proximity, locality and regional development are integrated in multiple scalar interactions. These multiscalar interactions and relations are mediated by objects and artefacts, and therefore they are often not seen as part of the networks.......The empirical and theoretical frameworks of transitions focus mainly on specific scale of change e.g. local, regional or national transitions. One reason for this lack of an integrative framework of territorial and spatial distribution of transitions process is the ambition of transition framework...... network perspective in order to develop the spatial dimensions of transitions. The paper is based on an ongoing research project of spatial dimensions of the transitions in energy production and consumption networks in the northern part of Denmark. The paper show by using an actor network perspective...

  10. An Autonomous Connectivity Restoration Algorithm Based on Finite State Machine for Wireless Sensor-Actor Networks

    Directory of Open Access Journals (Sweden)

    Ying Zhang

    2018-01-01

    Full Text Available With the development of autonomous unmanned intelligent systems, such as the unmanned boats, unmanned planes and autonomous underwater vehicles, studies on Wireless Sensor-Actor Networks (WSANs have attracted more attention. Network connectivity algorithms play an important role in data exchange, collaborative detection and information fusion. Due to the harsh application environment, abnormal nodes often appear, and the network connectivity will be prone to be lost. Network self-healing mechanisms have become critical for these systems. In order to decrease the movement overhead of the sensor-actor nodes, an autonomous connectivity restoration algorithm based on finite state machine is proposed. The idea is to identify whether a node is a critical node by using a finite state machine, and update the connected dominating set in a timely way. If an abnormal node is a critical node, the nearest non-critical node will be relocated to replace the abnormal node. In the case of multiple node abnormality, a regional network restoration algorithm is introduced. It is designed to reduce the overhead of node movements while restoration happens. Simulation results indicate the proposed algorithm has better performance on the total moving distance and the number of total relocated nodes compared with some other representative restoration algorithms.

  11. An Autonomous Connectivity Restoration Algorithm Based on Finite State Machine for Wireless Sensor-Actor Networks.

    Science.gov (United States)

    Zhang, Ying; Wang, Jun; Hao, Guan

    2018-01-08

    With the development of autonomous unmanned intelligent systems, such as the unmanned boats, unmanned planes and autonomous underwater vehicles, studies on Wireless Sensor-Actor Networks (WSANs) have attracted more attention. Network connectivity algorithms play an important role in data exchange, collaborative detection and information fusion. Due to the harsh application environment, abnormal nodes often appear, and the network connectivity will be prone to be lost. Network self-healing mechanisms have become critical for these systems. In order to decrease the movement overhead of the sensor-actor nodes, an autonomous connectivity restoration algorithm based on finite state machine is proposed. The idea is to identify whether a node is a critical node by using a finite state machine, and update the connected dominating set in a timely way. If an abnormal node is a critical node, the nearest non-critical node will be relocated to replace the abnormal node. In the case of multiple node abnormality, a regional network restoration algorithm is introduced. It is designed to reduce the overhead of node movements while restoration happens. Simulation results indicate the proposed algorithm has better performance on the total moving distance and the number of total relocated nodes compared with some other representative restoration algorithms.

  12. An Autonomous Connectivity Restoration Algorithm Based on Finite State Machine for Wireless Sensor-Actor Networks

    Science.gov (United States)

    Zhang, Ying; Wang, Jun; Hao, Guan

    2018-01-01

    With the development of autonomous unmanned intelligent systems, such as the unmanned boats, unmanned planes and autonomous underwater vehicles, studies on Wireless Sensor-Actor Networks (WSANs) have attracted more attention. Network connectivity algorithms play an important role in data exchange, collaborative detection and information fusion. Due to the harsh application environment, abnormal nodes often appear, and the network connectivity will be prone to be lost. Network self-healing mechanisms have become critical for these systems. In order to decrease the movement overhead of the sensor-actor nodes, an autonomous connectivity restoration algorithm based on finite state machine is proposed. The idea is to identify whether a node is a critical node by using a finite state machine, and update the connected dominating set in a timely way. If an abnormal node is a critical node, the nearest non-critical node will be relocated to replace the abnormal node. In the case of multiple node abnormality, a regional network restoration algorithm is introduced. It is designed to reduce the overhead of node movements while restoration happens. Simulation results indicate the proposed algorithm has better performance on the total moving distance and the number of total relocated nodes compared with some other representative restoration algorithms. PMID:29316702

  13. Finding The Most Important Actor in Online Crowd by Social Network Analysis

    Science.gov (United States)

    Yuliana, I.; Santosa, P. I.; Setiawan, N. A.; Sukirman

    2017-02-01

    Billion of people create trillions of connections through social media every single day. The increasing use of social media has led to dramatic changes in the of way science, government, healthcare, entertainment and enterprise operate. Large-scale participation in Technology-Mediated Social Participation (TMSP) system has opened up incredible new opportunities to deploy online crowd. This descriptive-correlational research used social network analysis (SNA) on data gathered from Fanpage Facebook of Greenpeace Indonesia related to important critical issues, the bushfires in 2015. SNA identifies relations on each member by sociometrics parameter such as three centrality (degree, closeness and betweenesse) for measuring and finding the most important actor in the online community. This paper use Fruchterman Rein-gold algorithm to visualize the online community in a graph, while Clauset-Newman-Moore is a technique to identify groups in community. As the result found 3735 vertices related to actors, 6927 edges as relation, 14 main actors in size order and 22 groups in Greenpeace Indonesia online community. This research contributes to organize some information for Greenpeace Indonesia managing their potency in online community to identify human behaviour.

  14. Actors and networks in resource conflict resolution under climate change in rural Kenya

    Science.gov (United States)

    Ngaruiya, Grace W.; Scheffran, Jürgen

    2016-05-01

    The change from consensual decision-making arrangements into centralized hierarchical chieftaincy schemes through colonization disrupted many rural conflict resolution mechanisms in Africa. In addition, climate change impacts on land use have introduced additional socio-ecological factors that complicate rural conflict dynamics. Despite the current urgent need for conflict-sensitive adaptation, resolution efficiency of these fused rural institutions has hardly been documented. In this context, we analyse the Loitoktok network for implemented resource conflict resolution structures and identify potential actors to guide conflict-sensitive adaptation. This is based on social network data and processes that are collected using the saturation sampling technique to analyse mechanisms of brokerage. We find that there are three different forms of fused conflict resolution arrangements that integrate traditional institutions and private investors in the community. To effectively implement conflict-sensitive adaptation, we recommend the extension officers, the council of elders, local chiefs and private investors as potential conduits of knowledge in rural areas. In conclusion, efficiency of these fused conflict resolution institutions is aided by the presence of holistic resource management policies and diversification in conflict resolution actors and networks.

  15. From the Actor to the Actions. Sociology and the Transformations of Intellectuals towards Network Society

    Directory of Open Access Journals (Sweden)

    Francesco Antonelli

    2016-07-01

    Full Text Available The purpose of this paper is to analyse the transformation of intellectuals in contemporary global post-industrial society, through a critical review on sociological studies and researches. The thesis is that contemporary intellectuals should not consider a socio-cultural élite or vanguard but a swarm of social actors defined by their relationship with the digital media and the economic sphere. After two introductive paragraphs focused on the critic approach – it is based on the new knowledge sociology –  the third and the fourth ones argues the most important studies on intellectuals wrote in industrial society age (theory of the New Class, New-Marxism theory, Weberanian theory, sociology of knowledge. The least paragraphs are focused on a discussion about the new sociology of intellectuals in a post-industrial society and the problem of the relationships between digital media and the intellectual actions in contemporary world.

  16. Network Theory and Religious Innovation

    DEFF Research Database (Denmark)

    Collar, Anna

    Collar, A. C. F. ‘Network Theory and Religious Innovation’. In Greek and Roman Networks in the Mediterranean, edited by I. Malkin, C. Constantakopoulou, K. Panagopoulou, 144-157. Abingdon: Routledge......Collar, A. C. F. ‘Network Theory and Religious Innovation’. In Greek and Roman Networks in the Mediterranean, edited by I. Malkin, C. Constantakopoulou, K. Panagopoulou, 144-157. Abingdon: Routledge...

  17. Power structure among the actors of financial support to the poor to access health services: Social network analysis approach.

    Science.gov (United States)

    Etemadi, Manal; Gorji, Hasan Abolghasem; Kangarani, Hannaneh Mohammadi; Ashtarian, Kioomars

    2017-12-01

    The extent of universal health coverage in terms of financial protection is worrisome in Iran. There are challenges in health policies to guarantee financial accessibility to health services, especially for poor people. Various institutions offer support to ensure that the poor have financial access to health services. The aim of this study is to investigate the relationship network among the institutions active in this field. This study is a policy document analysis. It evaluates the country's legal documents in the field of financial support to the poor for healthcare after the Islamic Revolution in Iran. The researchers looked for the documents on the related websites and referred to the related organizations. The social network analysis approach was chosen for the analysis of the documents. Block-modelling and multi-dimensional scaling (MDS) was used to determine the network structures. The UCINET software was employed to analyse the data. Most the main actors of this network are chosen from the government budget. There is no legal communication and cooperation among some of the actors because of their improper position in the network. Seven blocks have been clustered by CONCOR in terms of the actor's degree of similarity. The social distance among the actors of the seven blocks is very short. Power distribution in the field of financial support to the poor has a fragmented structure; however, it is mainly run by a dominant block consisting of The Supreme Council of Welfare and Social Security, Health Insurance Organization, and the Ministry of Health and Medical Education. The financial support for the poor network involves multiple actors. This variety has created a series of confusions in terms of the type, level, and scope of responsibilities among the actors. The weak presence legislative and regulatory institutions and also non-governmental institutions are the main weak points of this network. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. The radioactivity measurement in the Loire catchment basin. Actors, networks, data inventory

    International Nuclear Information System (INIS)

    2008-01-01

    The objective of this report on the Loire watershed was to broaden at all the nuclear installations of the watershed the method of synthesis made for Saint-Laurent-des-Eaux nuclear power plant, by resting on the whole of actors doing the radioactivity measurements in environment. This report shows that these actors are numerous. The measurement plans implemented have for objective to establish the radiological situation of environment, near or not the nuclear facilities, to detect the abnormal increase of radioactivity, to evaluate the exposure of populations to the ambient radioactivity, or to check the conformity of practices (nuclear activities) and products. This assessment enlightens the lack of a real global strategy in the organisation of the radioactivity measurement at the level of the watershed. The inventory of available data for the Loire watershed allowed to show the diversity of measurements realised. The I.R.S.N. is face to a complex situation of data return in the frame of the implementation of an information system of the national network of radioactivity measurement in environment. (N.C.)

  19. The Pursuit of Memory: Examining Art Teaching and Pedagogical Practices through Hannah Arendt's Actor-Spectator Theory

    Science.gov (United States)

    Lee, Mun Yee

    2011-01-01

    Memories of our schooling and teaching experiences shape our curriculum and pedagogical decision-making process in art education when we become teachers and teacher educators. In this paper, using Hannah Arendt's Actor-Spectator Theory, I engage in retrospective critical introspection of my practices as an art teacher and curriculum developer in…

  20. Identity construction and British Muslims' political activity: beyond rational actor theory.

    Science.gov (United States)

    Hopkins, Nick; Kahani-Hopkins, Vered

    2004-09-01

    Political activity is often addressed in terms of rational actor theory (RAT). We review RAT's psychological assumptions and highlight the neglect of collective identity. In turn, we view the perception of 'interest' as contingent upon constructions of identity and explore how different characterizations of collective identity are organized strategically so as to shape people's understandings of their interests and how they should act to realize them. Using examples taken from a study of British Muslims' political activity we emphasize the contested and strategic dimension to identity construction and analyse how activists addressing the same constituency construe Muslim identity in different ways so as to promote different conceptions of collective interest. Specifically, we explore the contested invocations of Prophetic example in the definition of Muslim identity. The broader thrust behind this work is a critique of the sharp dichotomization of Muslim and non-Muslim political activity. We maintain that essentially similar processes of identity construction underlie all attempts to organize collective sentiment and political action (including that comprising so-called 'conventional' electoralist politics in the West), and that conceiving of identity as a site of political struggle underscores the inadequacy of Orientalist characterizations of Muslim identity in terms of a singular, transhistorical essence.

  1. On Efficient Link Recommendation in Social Networks Using Actor-Fact Matrices

    Directory of Open Access Journals (Sweden)

    Michał Ciesielczyk

    2015-01-01

    Full Text Available Link recommendation is a popular research subject in the field of social network analysis and mining. Often, the main emphasis is put on the development of new recommendation algorithms, semantic enhancements to existing solutions, design of new similarity measures, and so forth. However, relatively little scientific attention has been paid to the impact that various data representation models have on the performance of recommendation algorithms. And by performance we do not mean the time or memory efficiency of algorithms, but the precision and recall of recommender systems. Our recent findings unanimously show that the choice of network representation model has an important and measurable impact on the quality of recommendations. In this paper we argue that the computation quality of link recommendation algorithms depends significantly on the social network representation and we advocate the use of actor-fact matrix as the best alternative. We verify our findings using several state-of-the-art link recommendation algorithms, such as SVD, RSVD, and RRI using both single-relation and multirelation dataset.

  2. On the character and production of 'active participation' in neuro-rehabilitation: an Actor-Network perspective.

    Science.gov (United States)

    Horton, Simon; Mares, Kathryn; Coull, Neil; Poland, Fiona

    2017-11-01

    The importance of patients' active involvement in neuro-rehabilitation after acquired brain injury has been consistently emphasised in recent years. However, most approaches fail to show how 'active participation' is practically enacted, focusing on individualised explanations of patient choice and behaviours, or notions of inherent patient traits. Using actor-network theory (ANT) as a sensitising concept, we investigated neuro-rehabilitation practices, asking how participation is shaped through biological and socio-material specificities, how rights to knowledge and expertise are constructed, and how a body acclimatises and adjusts within an order of participation and transformation. We analysed video-recorded fieldwork extracts, examining the work of adjusting, testing and transforming; the construction of competence and incompetence; and material and social processes involved in the division of the body and its re-composition. Our findings show how an ANT-sensitised approach provides a critical understanding and context-specific characterisation of 'active participation', produced through the association of heterogeneous actors at any one time. Such specificity and the distribution of work suggest that efforts to account for optimum therapy 'dosages', and clinical attention to establishing individually-located levels of 'self-efficacy' or 'motivation' are misdirected. The performance of 'active participation', rather, should be re-imagined as a product of diverse, mutually attuned entities. A Virtual Abstract of this paper can be viewed at: https://www.youtube.com/channel/UC_979cmCmR9rLrKuD7z0ycA. © 2017 Foundation for the Sociology of Health & Illness.

  3. Holding-based network of nations based on listed energy companies: An empirical study on two-mode affiliation network of two sets of actors

    Science.gov (United States)

    Li, Huajiao; Fang, Wei; An, Haizhong; Gao, Xiangyun; Yan, Lili

    2016-05-01

    Economic networks in the real world are not homogeneous; therefore, it is important to study economic networks with heterogeneous nodes and edges to simulate a real network more precisely. In this paper, we present an empirical study of the one-mode derivative holding-based network constructed by the two-mode affiliation network of two sets of actors using the data of worldwide listed energy companies and their shareholders. First, we identify the primitive relationship in the two-mode affiliation network of the two sets of actors. Then, we present the method used to construct the derivative network based on the shareholding relationship between two sets of actors and the affiliation relationship between actors and events. After constructing the derivative network, we analyze different topological features on the node level, edge level and entire network level and explain the meanings of the different values of the topological features combining the empirical data. This study is helpful for expanding the usage of complex networks to heterogeneous economic networks. For empirical research on the worldwide listed energy stock market, this study is useful for discovering the inner relationships between the nations and regions from a new perspective.

  4. Theory of spatial networks

    Energy Technology Data Exchange (ETDEWEB)

    Watanabe, T

    1983-01-01

    A new framework of synchronous parallel processing systems called spatial networks is examined, in which the family of all cellular automata is included perfectly. This framework is free from the two restrictions of cellular automata of which one is the finiteness of the set of states of a cell and the other is the countability of an array space. Throughout this article, the relationships between function and structure of spatial networks are considered. First, the necessary and sufficient condition for spatial networks to be uniformly interconnected is given. That for spatial networks to be finitely interconnected is also given with a topological approach. The characterization theorem of cellular automata comes from these results. Second, it is shown that finitely and uniformly interconnected linear spatial networks can be characterized by the convolution form. Last, the conditions for their global mappings to be injective or surjective are discussed. 10 references.

  5. The Interactive Constitution of Actors in Industrial Networks: The Case of the Norwegian City of Alesund

    OpenAIRE

    Frans Prenkert

    2013-01-01

    The actor-dimension of the Activitiy-Resource-Actor (ARA)-model has not gained the same attention among Industrial Marketing and Purchasing (IMP) scholars as the resource and activity dimensions. However, the issue of what an actor actually is, in the sense of its interactive constitution, is important from an industrial marketing and purchasing perspective that emphasizes the interactive character of the business landscape. This is adressed in this paper. As a concequence of their interactiv...

  6. Balance of power theory meets Al Qaeda : dynamics of non-state actor balancing in postinternational politics

    OpenAIRE

    Denk, Aytaç

    2008-01-01

    Ankara : The Department of International Relations, Bilkent University, 2008. Thesis (Master's) -- Bilkent University, 2008. Includes bibliographical references leaves 196-207. The bulk of studies on the balance of power, which constitutes balance of power theory, suggest that only states are involved in balance of power dynamics. This thesis maintains that exclusion of non-state actors (NSAs) from balance of power dynamics constitutes a significant gap in balance of power t...

  7. Fractal actors and infrastructures

    DEFF Research Database (Denmark)

    Bøge, Ask Risom

    2011-01-01

    -network-theory (ANT) into surveillance studies (Ball 2002, Adey 2004, Gad & Lauritsen 2009). In this paper, I further explore the potential of this connection by experimenting with Marilyn Strathern’s concept of the fractal (1991), which has been discussed in newer ANT literature (Law 2002; Law 2004; Jensen 2007). I...... under surveillance. Based on fieldwork conducted in 2008 and 2011 in relation to my Master’s thesis and PhD respectively, I illustrate fractal concepts by describing the acts, actors and infrastructure that make up the ‘DNA surveillance’ conducted by the Danish police....

  8. Actor-networking ceta-sociality, or, what is sociological about contemporary whales?

    DEFF Research Database (Denmark)

    Blok, Anders

    2007-01-01

    -network theory (ANT) allows for the inclusion of non-human ‘actants' (like whales) into the fabric of sociality. In the ontology of ANT, sociality emerges as semiotic-material configurations of humans, animals and technologies. Starting from a critical review of the work by Adrian Franklin on growing......-denser networks of humans and non-humans, sociology is in need of theoretical reconfiguration. Towards this end, some prospects and limitations for ecologising sociology are set out, suggesting how sociology might come to contribute to the project of living in a hybrid world....

  9. What is a conservation actor?

    Directory of Open Access Journals (Sweden)

    Paul Jepson

    2011-01-01

    Full Text Available As a crisis-oriented discipline, conservation biology needs actions to understand the state of nature and thwart declines in biodiversity. Actors-traditionally individuals, institutions, and collectives-have been central to delivering such goals in practice. However, the definition of actors within the discipline has been narrow and their role in influencing conservation outcomes inadequately conceptualised. In this paper, we examine the question ′What is a conservation actor?′ Who or what creates the capacity to influence conservation values and actions? Drawing from theoretical developments in Actor-Network Theory and collective governance, we argue that the concept of an actor in conservation biology should be broadened to include non-humans, such as species and devices, because they have the agency and ability to influence project goals and outcomes. We illustrate this through four examples: the Asian elephant, International Union for Conservation of Nature red lists, the High Conservation Value approach, and an Integrated Conservation and Development Project. We argue that a broader conceptualisation of actors in conservation biology will produce new forms of understanding that could open up new areas of conservation research, enhance practice and draw attention to spheres of conservation activity that might require stronger oversight and governance.

  10. Quantum network theory

    International Nuclear Information System (INIS)

    Yurke, B.; Denker, J.S.

    1984-01-01

    A general approach, within the framework of canonical quantization, is described for analyzing the quantum behavior of complicated electronic circuits. This approach is capable of dealing with electrical networks having nonlinear or dissipative elements. The techniques are used to analyze a degenerate parametric amplifier, a device capable of generating squeezed coherent state signals. A circuit capable of performing back-action-evading electrical measurements is also discussed. (author)

  11. Local-regional networks of persons with abilities in radioprotection and other actors in radioprotection. Audit report

    International Nuclear Information System (INIS)

    Lefaure, Ch.

    2009-03-01

    As the regulation requires the existence of persons with abilities in radioprotection (PCR, personnes competentes en radioprotection) in many industrial, medical or research activities where ionizing radiations are present, in order to improve worker protection, these professionals who are much less acknowledged in these sectors than in the nuclear sector, felt the need to gather in regional and sector-based networks. This report proposes a presentation of three existing networks (the APCRAP, the Grand-Ouest network, and the Aquitaine-Sud-Ouest network). For each of them, the report addresses the following aspects: creation, objectives, statutes, members, activities, human, technical and financial resources, role. Then answers to a survey and to interviews are analyzed with respect to the professional sector and to the region, in terms of expectations towards the networks, and in terms of network operation and services. Interviews of institutional actors and union and management representatives are also analysed

  12. Potential theory for directed networks.

    Directory of Open Access Journals (Sweden)

    Qian-Ming Zhang

    Full Text Available Uncovering factors underlying the network formation is a long-standing challenge for data mining and network analysis. In particular, the microscopic organizing principles of directed networks are less understood than those of undirected networks. This article proposes a hypothesis named potential theory, which assumes that every directed link corresponds to a decrease of a unit potential and subgraphs with definable potential values for all nodes are preferred. Combining the potential theory with the clustering and homophily mechanisms, it is deduced that the Bi-fan structure consisting of 4 nodes and 4 directed links is the most favored local structure in directed networks. Our hypothesis receives strongly positive supports from extensive experiments on 15 directed networks drawn from disparate fields, as indicated by the most accurate and robust performance of Bi-fan predictor within the link prediction framework. In summary, our main contribution is twofold: (i We propose a new mechanism for the local organization of directed networks; (ii We design the corresponding link prediction algorithm, which can not only testify our hypothesis, but also find out direct applications in missing link prediction and friendship recommendation.

  13. Potential Theory for Directed Networks

    Science.gov (United States)

    Zhang, Qian-Ming; Lü, Linyuan; Wang, Wen-Qiang; Zhou, Tao

    2013-01-01

    Uncovering factors underlying the network formation is a long-standing challenge for data mining and network analysis. In particular, the microscopic organizing principles of directed networks are less understood than those of undirected networks. This article proposes a hypothesis named potential theory, which assumes that every directed link corresponds to a decrease of a unit potential and subgraphs with definable potential values for all nodes are preferred. Combining the potential theory with the clustering and homophily mechanisms, it is deduced that the Bi-fan structure consisting of 4 nodes and 4 directed links is the most favored local structure in directed networks. Our hypothesis receives strongly positive supports from extensive experiments on 15 directed networks drawn from disparate fields, as indicated by the most accurate and robust performance of Bi-fan predictor within the link prediction framework. In summary, our main contribution is twofold: (i) We propose a new mechanism for the local organization of directed networks; (ii) We design the corresponding link prediction algorithm, which can not only testify our hypothesis, but also find out direct applications in missing link prediction and friendship recommendation. PMID:23408979

  14. The social network of actors influencing age discrimination in the human resources recruiting process

    Directory of Open Access Journals (Sweden)

    Aurelian SOFICĂ

    2012-06-01

    Full Text Available The aim of the paper is to map the area where the social construction of age discrimination in the recruiting process is perceived as taking place, especially those individuals or organized groups with enough power and interest to influence this unethical reality. The research was carried out in 2010 and 2011 in Cluj-Napoca, Romania; it uses multiple qualitative methods (focus-group and interviews and covers three layers of perception: candidate’s perception, employer’s perception and recruiter’s perception. Usually, the main social actors publically perceived as influencing age discrimination in the recruiting process are the employers (as the main responsible, some public institutions (as guardians and the candidates (as victims. The findings of the paper show that the number of social actors perceived as interested and with power by the main social actors (employers and candidates is much higher than the number classically targeted by researchers, reaching 20 or more

  15. Revealing the neural networks associated with processing of natural social interaction and the related effects of actor-orientation and face-visibility.

    Science.gov (United States)

    Saggar, Manish; Shelly, Elizabeth Walter; Lepage, Jean-Francois; Hoeft, Fumiko; Reiss, Allan L

    2014-01-01

    Understanding the intentions and desires of those around us is vital for adapting to a dynamic social environment. In this paper, a novel event-related functional Magnetic Resonance Imaging (fMRI) paradigm with dynamic and natural stimuli (2s video clips) was developed to directly examine the neural networks associated with processing of gestures with social intent as compared to nonsocial intent. When comparing social to nonsocial gestures, increased activation in both the mentalizing (or theory of mind) and amygdala networks was found. As a secondary aim, a factor of actor-orientation was included in the paradigm to examine how the neural mechanisms differ with respect to personal engagement during a social interaction versus passively observing an interaction. Activity in the lateral occipital cortex and precentral gyrus was found sensitive to actor-orientation during social interactions. Lastly, by manipulating face-visibility we tested whether facial information alone is the primary driver of neural activation differences observed between social and nonsocial gestures. We discovered that activity in the posterior superior temporal sulcus (pSTS) and fusiform gyrus (FFG) was partially driven by observing facial expressions during social gestures. Altogether, using multiple factors associated with processing of natural social interaction, we conceptually advance our understanding of how social stimuli is processed in the brain and discuss the application of this paradigm to clinical populations where atypical social cognition is manifested as a key symptom. © 2013.

  16. Revealing the neural networks associated with processing of natural social interaction and the related effects of actor-orientation and face-visibility

    Science.gov (United States)

    Saggar, Manish; Shelly, Elizabeth Walter; Lepage, Jean-Francois; Hoeft, Fumiko; Reiss, Allan L.

    2013-01-01

    Understanding the intentions and desires of those around us is vital for adapting to a dynamic social environment. In this paper, a novel event-related functional Magnetic Resonance Imaging (fMRI) paradigm with dynamic and natural stimuli (2s video clips) was developed to directly examine the neural networks associated with processing of gestures with social intent as compared to nonsocial intent. When comparing social to nonsocial gestures, increased activation in both the mentalizing (or theory of mind) and amygdala networks were found. As a secondary aim, a factor of actor-orientation was included in the paradigm to examine how the neural mechanisms differ with respect to personal engagement during a social interaction versus passively observing an interaction. Activity in the lateral occipital cortex and precentral gyrus were found sensitive to actor-orientation during social interactions. Lastly, by manipulating face-visibility we tested whether facial information alone is the primary driver of neural activation differences observed between social and nonsocial gestures. We discovered that activity in the posterior superior temporal sulcus (pSTS) and fusiform gyrus (FFG) were partially driven by observing facial expressions during social gestures. Altogether, using multiple factors associated with processing of natural social interaction, we conceptually advance our understanding of how social stimuli is processed in the brain and discuss the application of this paradigm to clinical populations where atypical social cognition is manifested as a key symptom. PMID:24084068

  17. A Theory of Network Tracing

    Science.gov (United States)

    Acharya, Hrishikesh B.; Gouda, Mohamed G.

    Traceroute is a widely used program for computing the topology of any network in the Internet. Using Traceroute, one starts from a node and chooses any other node in the network. Traceroute obtains the sequence of nodes that occur between these two nodes, as specified by the routing tables in these nodes. Each use of Traceroute in a network produces a trace of nodes that constitute a simple path in this network. In every trace that is produced by Traceroute, each node occurs either by its unique identifier, or by the anonymous identifier"*". In this paper, we introduce the first theory aimed at answering the following important question. Is there an algorithm to compute the topology of a network N from a trace set T that is produced by using Traceroute in network N, assuming that each edge in N occurs in at least one trace in T, and that each node in N occurs by its unique identifier in at least one trace in T? We prove that the answer to this question is "No" if N is an even ring or a general network. However, it is "Yes" if N is a tree or an odd ring. The answer is also "No" if N is mostly-regular, but "Yes" if N is a mostly-regular even ring.

  18. Modeling acquaintance networks based on balance theory

    Directory of Open Access Journals (Sweden)

    Vukašinović Vida

    2014-09-01

    Full Text Available An acquaintance network is a social structure made up of a set of actors and the ties between them. These ties change dynamically as a consequence of incessant interactions between the actors. In this paper we introduce a social network model called the Interaction-Based (IB model that involves well-known sociological principles. The connections between the actors and the strength of the connections are influenced by the continuous positive and negative interactions between the actors and, vice versa, the future interactions are more likely to happen between the actors that are connected with stronger ties. The model is also inspired by the social behavior of animal species, particularly that of ants in their colony. A model evaluation showed that the IB model turned out to be sparse. The model has a small diameter and an average path length that grows in proportion to the logarithm of the number of vertices. The clustering coefficient is relatively high, and its value stabilizes in larger networks. The degree distributions are slightly right-skewed. In the mature phase of the IB model, i.e., when the number of edges does not change significantly, most of the network properties do not change significantly either. The IB model was found to be the best of all the compared models in simulating the e-mail URV (University Rovira i Virgili of Tarragona network because the properties of the IB model more closely matched those of the e-mail URV network than the other models

  19. Research Note: The consequences of different methods for handling missing network data in Stochastic Actor Based Models.

    Science.gov (United States)

    Hipp, John R; Wang, Cheng; Butts, Carter T; Jose, Rupa; Lakon, Cynthia M

    2015-05-01

    Although stochastic actor based models (e.g., as implemented in the SIENA software program) are growing in popularity as a technique for estimating longitudinal network data, a relatively understudied issue is the consequence of missing network data for longitudinal analysis. We explore this issue in our research note by utilizing data from four schools in an existing dataset (the AddHealth dataset) over three time points, assessing the substantive consequences of using four different strategies for addressing missing network data. The results indicate that whereas some measures in such models are estimated relatively robustly regardless of the strategy chosen for addressing missing network data, some of the substantive conclusions will differ based on the missing data strategy chosen. These results have important implications for this burgeoning applied research area, implying that researchers should more carefully consider how they address missing data when estimating such models.

  20. Game theory at work: OR models and algorythms to solve multi-actor heterogeneous decision problems

    NARCIS (Netherlands)

    Sáiz Pérez, M.E.

    2007-01-01

    Key words: Game theory, operations research, optimisation methods, algorithms. The objective of this thesis is to explore the potential of combining Game Theory (GT) models with Operations Research (OR) modelling. This includes development of algorithms to solve these complex OR models for

  1. Interdisciplinary and physics challenges of network theory

    Science.gov (United States)

    Bianconi, Ginestra

    2015-09-01

    Network theory has unveiled the underlying structure of complex systems such as the Internet or the biological networks in the cell. It has identified universal properties of complex networks, and the interplay between their structure and dynamics. After almost twenty years of the field, new challenges lie ahead. These challenges concern the multilayer structure of most of the networks, the formulation of a network geometry and topology, and the development of a quantum theory of networks. Making progress on these aspects of network theory can open new venues to address interdisciplinary and physics challenges including progress on brain dynamics, new insights into quantum technologies, and quantum gravity.

  2. The tensor network theory library

    Science.gov (United States)

    Al-Assam, S.; Clark, S. R.; Jaksch, D.

    2017-09-01

    In this technical paper we introduce the tensor network theory (TNT) library—an open-source software project aimed at providing a platform for rapidly developing robust, easy to use and highly optimised code for TNT calculations. The objectives of this paper are (i) to give an overview of the structure of TNT library, and (ii) to help scientists decide whether to use the TNT library in their research. We show how to employ the TNT routines by giving examples of ground-state and dynamical calculations of one-dimensional bosonic lattice system. We also discuss different options for gaining access to the software available at www.tensornetworktheory.org.

  3. Teachers' professional development in a community: A study of the central actors, their networks and web-based learning

    Directory of Open Access Journals (Sweden)

    Jiri Lallimo

    2008-07-01

    Full Text Available The goal of this article was to study teachers' professional development related to web-based learning in the context of the teacher community. The object was to learn in what kind of networks teachers share the knowledge of web-based learning and what are the factors in the community that support or challenge teachers professional development of web-based learning. The findings of the study revealed that there are teachers who are especially active, called the central actors in this study, in the teacher community who collaborate and share knowledge of web-based learning. These central actors share both technical and pedagogical knowledge of web-based learning in networks that include both internal and external relations in the community and involve people, artefacts and a variety of media. Furthermore, the central actors appear to bridge different fields of teaching expertise in their community.According to the central actors' experiences the important factors that support teachers' professional development of web-based learning in the community are; the possibility to learn from colleagues and from everyday working practices, an emotionally safe atmosphere, the leader's personal support and community-level commitment. Also, the flexibility in work planning, challenging pupils, shared lessons with colleagues, training events in an authentic work environment and colleagues' professionalism are considered meaningful for professional development. As challenges, the knowledge sharing of web-based learning in the community needs mutual interests, transactive memory, time and facilities, peer support, a safe atmosphere and meaningful pedagogical practices.On the basis of the findings of the study it is suggested that by intensive collaboration related to web-based learning it may be possible to break the boundaries of individual teachership and create such sociocultural activities which support collaborative professional development in the teacher

  4. Towards a multi-actor theory of public value co-creation

    DEFF Research Database (Denmark)

    Bryson, John; Sancino, Alessandro; Benington, John

    2017-01-01

    This essay suggests changes to the theory of public value and, in particular, the strategic triangle framework, in order to adapt it to an emerging world where policy makers and managers in the public, private, voluntary and informal community sectors have to somehow separately and jointly create...

  5. Networks and learning in game theory

    NARCIS (Netherlands)

    Kets, W.

    2008-01-01

    This work concentrates on two topics, networks and game theory, and learning in games. The first part of this thesis looks at network games and the role of incomplete information in such games. It is assumed that players are located on a network and interact with their neighbors in the network.

  6. Actores Secundarios

    Directory of Open Access Journals (Sweden)

    Manuel Gárate

    2007-09-01

    Full Text Available Cámara digital en mano y provistos de los recuerdos y una sesuda investigación de 3 años, los realizadores de “Actores Secundarios” nos transportan al último periodo de la dictadura militar chilena. Pero esta vez no se trata de un relato épico sobre los actores tradicionales de la lucha por la democracia, sino de una generación prácticamente olvidada y que movilizó a miles de adolescentes contra un régimen que los ahogaba. “Actores Secundarios” es una crónica construida de los fragmentos de ...

  7. Validation of Networks Derived from Snowball Sampling of Municipal Science Education Actors

    Science.gov (United States)

    von der Fehr, Ane; Sølberg, Jan; Bruun, Jesper

    2018-01-01

    Social network analysis (SNA) has been used in many educational studies in the past decade, but what these studies have in common is that the populations in question in most cases are defined and known to the researchers studying the networks. Snowball sampling is an SNA methodology most often used to study hidden populations, for example, groups…

  8. Networks in Action: New Actors and Practices in Education Policy in Brazil

    Science.gov (United States)

    Shiroma, Eneida Oto

    2014-01-01

    This paper focuses on the role of networks in the policy-making process in education and discusses the potential of network analysis as an analytical tool for education policy research. Drawing on publically available data from personal or institutional websites, this paper reports the findings from research carried out between 2005 and 2011.…

  9. From Cybercrime to Cyborg Crime: Botnets as Hybrid Criminal Actor-Networks

    NARCIS (Netherlands)

    van der Wagen, Wytske; Pieters, Wolter

    2015-01-01

    Botnets, networks of infected computers controlled by a commander, increasingly play a role in a broad range of cybercrimes. Although often studied from technological perspectives, a criminological perspective could elucidate the organizational structure of botnets and how to counteract them.

  10. Ecological networks: a spatial concept for multi-actor planning of sustainable landscapes

    NARCIS (Netherlands)

    Opdam, P.F.M.; Steingröver, E.G.; Rooij, van S.A.M.

    2006-01-01

    In this paper, we propose the ecological network concept as a suitable basis for inserting biodiversity conservation into sustainable landscape development. For landscapes to be ecologically sustainable, the landscape structure should support those ecological processes required for the landscape to

  11. From Cybercrime to Cyborg Crime : Botnets as Hybrid Criminal Actor-Networks

    NARCIS (Netherlands)

    van der Wagen, Wytske; Pieters, Wolter

    2015-01-01

    Botnets, networks of infected computers controlled by a commander, increasingly play a role in a broad range of cybercrimes. Although often studied from technological perspectives, a criminological perspective could elucidate the organizational structure of botnets and how to counteract them.

  12. Wireless network security theories and applications

    CERN Document Server

    Chen, Lei; Zhang, Zihong

    2013-01-01

    Wireless Network Security Theories and Applications discusses the relevant security technologies, vulnerabilities, and potential threats, and introduces the corresponding security standards and protocols, as well as provides solutions to security concerns. Authors of each chapter in this book, mostly top researchers in relevant research fields in the U.S. and China, presented their research findings and results about the security of the following types of wireless networks: Wireless Cellular Networks, Wireless Local Area Networks (WLANs), Wireless Metropolitan Area Networks (WMANs), Bluetooth

  13. Governance network theory: Past, present and future

    NARCIS (Netherlands)

    E-H. Klijn (Erik-Hans); J.F.M. Koppenjan (Joop)

    2012-01-01

    markdownabstract__Abstract__ This article argues that governance network theory (GNT) has developed into a fullyfledged theory that has gained prominence within public administration. The emergence of New Public Governance opens up new challenges, however, and instead of governance networks and

  14. Structuring an integrated care system: interpreted through the enacted diversity of the actors involved – the case of a French healthcare network

    Directory of Open Access Journals (Sweden)

    Corinne Grenier

    2011-02-01

    Full Text Available Research question: We are looking at the process of structuring an integrated care system as an innovative process that swings back and forth between the diversity of the actors involved, local aspirations and national and regional regulations. We believe that innovation is enriched by the variety of the actors involved, but may also be blocked or disrupted by that diversity. Our research aims to add to other research, which, when questioning these integrated systems, analyses how the actors involved deal with diversity without really questioning it. Case study: The empirical basis of the paper is provided by case study analysis. The studied integrated care system is a French healthcare network that brings together healthcare professionals and various organisations in order to improve the way in which interventions are coordinated and formalised, in order to promote better detection and diagnosis procedures and the implementation of a care protocol. We consider this case as instrumental in developing theoretical proposals for structuring an integrated care system in light of the diversity of the actors involved. Results and discussion: We are proposing a model for structuring an integrated care system in light of the enacted diversity of the actors involved. This model is based on three factors: the diversity enacted by the leaders, three stances for considering the contribution made by diversity in the structuring process and the specific leading role played by those in charge of the structuring process.  Through this process, they determined how the actors involved in the project were differentiated, and on what basis those actors were involved. By mobilizing enacted diversity, the leaders are seeking to channel the emergence of a network in light of their own representation of that network. This model adds to published research on the structuring of integrated care systems.

  15. Structuring an integrated care system: interpreted through the enacted diversity of the actors involved – the case of a French healthcare network

    Directory of Open Access Journals (Sweden)

    Corinne Grenier

    2011-02-01

    Full Text Available Research question: We are looking at the process of structuring an integrated care system as an innovative process that swings back and forth between the diversity of the actors involved, local aspirations and national and regional regulations. We believe that innovation is enriched by the variety of the actors involved, but may also be blocked or disrupted by that diversity. Our research aims to add to other research, which, when questioning these integrated systems, analyses how the actors involved deal with diversity without really questioning it.Case study: The empirical basis of the paper is provided by case study analysis. The studied integrated care system is a French healthcare network that brings together healthcare professionals and various organisations in order to improve the way in which interventions are coordinated and formalised, in order to promote better detection and diagnosis procedures and the implementation of a care protocol. We consider this case as instrumental in developing theoretical proposals for structuring an integrated care system in light of the diversity of the actors involved.Results and discussion: We are proposing a model for structuring an integrated care system in light of the enacted diversity of the actors involved. This model is based on three factors: the diversity enacted by the leaders, three stances for considering the contribution made by diversity in the structuring process and the specific leading role played by those in charge of the structuring process.  Through this process, they determined how the actors involved in the project were differentiated, and on what basis those actors were involved. By mobilizing enacted diversity, the leaders are seeking to channel the emergence of a network in light of their own representation of that network. This model adds to published research on the structuring of integrated care systems.

  16. Partner-specific behavior in social networks : Coordination among actors with heterogeneous preferences

    NARCIS (Netherlands)

    van Gerwen, Nikki; Buskens, Vincent

    2018-01-01

    Conventions guide our daily behavior. If everyone agrees on what the best convention is, coordination is easy. We study coordination games in which individuals have conflicting preferences. Theoretical arguments and experimental tests on conventions in networks start too much from the assumption

  17. Towards a new perspective of managing ideas in front-end innovation as actor networks

    DEFF Research Database (Denmark)

    Vagn, Anna Rose; Clausen, Christian; Gish, Liv

    2013-01-01

    For decades the innovation process in R&D organisations has been discussed. Product development processes is well-established in R&D organisations and improvements has been implemented through theories as Lean product development and agile methods. In recent decades, more diffuse processes have...

  18. The Business Perspective of Cloud Computing: Actors, Roles, and Value Networks

    OpenAIRE

    Leimeister, Stefanie;Riedl, Christoph;Böhm, Markus;Krcmar, Helmut

    2014-01-01

    With the rise of a ubiquitous provision of computing resources over the past years, cloud computing has been established as a prominent research topic. Many researchers, however, focus exclusively on the technical aspects of cloud computing, thereby neglecting the business opportunities and potentials cloud computing can offer. Enabled through this technology, new market players and business value networks arise and break up the traditional value chain of service provision. The focus of this ...

  19. Short Cuts and Extended Techniques: Rethinking Relations between Technology and Educational Theory

    Science.gov (United States)

    Thumlert, Kurt; de Castell, Suzanne; Jenson, Jennifer

    2015-01-01

    Building upon a recent call to renew actor-network theory (ANT) for educational research, this article reconsiders relations between technology and educational theory. Taking cues from actor-network theorists, this discussion considers the technologically-mediated networks in which learning actors are situated, acted upon, and acting, and traces…

  20. An actor-based model of social network influence on adolescent body size, screen time, and playing sports.

    Directory of Open Access Journals (Sweden)

    David A Shoham

    Full Text Available Recent studies suggest that obesity may be "contagious" between individuals in social networks. Social contagion (influence, however, may not be identifiable using traditional statistical approaches because they cannot distinguish contagion from homophily (the propensity for individuals to select friends who are similar to themselves or from shared environmental influences. In this paper, we apply the stochastic actor-based model (SABM framework developed by Snijders and colleagues to data on adolescent body mass index (BMI, screen time, and playing active sports. Our primary hypothesis was that social influences on adolescent body size and related behaviors are independent of friend selection. Employing the SABM, we simultaneously modeled network dynamics (friendship selection based on homophily and structural characteristics of the network and social influence. We focused on the 2 largest schools in the National Longitudinal Study of Adolescent Health (Add Health and held the school environment constant by examining the 2 school networks separately (N = 624 and 1151. Results show support in both schools for homophily on BMI, but also for social influence on BMI. There was no evidence of homophily on screen time in either school, while only one of the schools showed homophily on playing active sports. There was, however, evidence of social influence on screen time in one of the schools, and playing active sports in both schools. These results suggest that both homophily and social influence are important in understanding patterns of adolescent obesity. Intervention efforts should take into consideration peers' influence on one another, rather than treating "high risk" adolescents in isolation.

  1. Quality of Care as an Emergent Phenomenon out of a Small-World Network of Relational Actors.

    Science.gov (United States)

    Fiorini, Rodolfo; De Giacomo, Piero; Marconi, Pier Luigi; L'Abate, Luciano

    2014-01-01

    In Healthcare Decision Support System, the development and evaluation of effective "Quality of Care" (QOC) indicators, in simulation-based training, are key feature to develop resilient and antifragile organization scenarios. Is it possible to conceive of QOC not only as a result of a voluntary and rational decision, imposed or even not, but also as an overall system "emergent phenomenon" out of a small-world network of relational synthetic actors, endowed with their own personality profiles to simulate human behaviour (for short, called "subjects")? In order to answer this question and to observe the phenomena of real emergence we should use computational models of high complexity, with heavy computational load and extensive computational time. Nevertheless, De Giacomo's Elementary Pragmatic Model (EPM) intrinsic self-reflexive functional logical closure enables to run simulation examples to classify the outcomes grown out of a small-world network of relational subjects fast and effectively. Therefore, it is possible to take note and to learn of how much strategic systemic interventions can induce context conditions of QOC facilitation, which can improve the effectiveness of specific actions, which otherwise might be paradoxically counterproductive also. Early results are so encouraging to use EPM as basic block to start designing more powerful Evolutive Elementary Pragmatic Model (E2PM) for real emergence computational model, to cope with ontological uncertainty at system level.

  2. Actor and partner effects of perceived HIV stigma on social network components among people living with HIV/AIDS and their caregivers.

    Science.gov (United States)

    Hao, Chun; Liu, Hongjie

    2015-06-01

    Few studies have investigated the relationship between HIV stigma and social network components at the dyadic level. The objective of this study was to examine the actor and partner effects of perceived HIV stigma by people living with HIV/AIDS (PLWHAs) and their caregivers on social network variables at the dyadic level. An egocentric social network study was conducted among 147 dyads consisting of one PLWHA and one caregiver (294 participants) in Nanning, China. The actor-partner interdependence model (APIM) was used to analyze the relationships between perceived HIV stigma and social network components (network relations, network structures, and network functions) at the dyadic level. We found in this dyadic analysis that: (1) social network components were similar between PLWHAs and their caregivers; (2) HIV stigma perceived by PLWHAs influenced their own social network components, whereas this influence did not exist between caregivers' perceived HIV stigma and their own social network components; (3) a few significant partner effects were observed between HIV stigma and social network components among both PLWHAs and caregivers. The interrelationships between HIV stigma and social network components were complex at the dyadic level. Future interventions programs targeting HIV stigma should focus on the interpersonal relationship at the dyadic level, beyond the intrapersonal factors. © The Author(s) 2014.

  3. Simposi Internacional "Changing politics through digital networks: the role of ICTs in the formation of new social and political actors and actions"

    Directory of Open Access Journals (Sweden)

    Rosa Borge

    2008-02-01

    Full Text Available

    Participació en el Simposi Internacional "Changing politics through digital networks: the role of ICTs in the formation of new social and political actors and actions", que va tenir lloc a la Universitat de Florència els dies 5 i 6 d'octubre de 2007.

  4. Queuing theory and telecommunications networks and applications

    CERN Document Server

    Giambene, Giovanni

    2014-01-01

    This book provides a basic description of current networking technologies and protocols as well as important tools for network performance analysis based on queuing theory. The second edition adds selected contents in the first part of the book for what concerns: (i) the token bucket regulator and traffic shaping issues; (ii) the TCP protocol congestion control that has a significant part in current networking; (iii) basic satellite networking issues; (iv) adding details on QoS support in IP networks. The book is organized so that networking technologies and protocols (Part I) are first and are then followed by theory and exercises with applications to the different technologies and protocols (Part II). This book is intended as a textbook for master level courses in networking and telecommunications sectors.

  5. Matching theory for wireless networks

    CERN Document Server

    Han, Zhu; Saad, Walid

    2017-01-01

    This book provides the fundamental knowledge of the classical matching theory problems. It builds up the bridge between the matching theory and the 5G wireless communication resource allocation problems. The potentials and challenges of implementing the semi-distributive matching theory framework into the wireless resource allocations are analyzed both theoretically and through implementation examples. Academics, researchers, engineers, and so on, who are interested in efficient distributive wireless resource allocation solutions, will find this book to be an exceptional resource. .

  6. Understanding the complex relationships among actors involved in the implementation of public-private mix (PPM) for TB control in India, using social theory.

    Science.gov (United States)

    Salve, Solomon; Harris, Kristine; Sheikh, Kabir; Porter, John D H

    2018-06-07

    Public Private Partnerships (PPP) are increasingly utilized as a public health strategy for strengthening health systems and have become a core component for the delivery of TB control services in India, as promoted through national policy. However, partnerships are complex systems that rely on relationships between a myriad of different actors with divergent agendas and backgrounds. Relationship is a crucial element of governance, and relationship building an important aspect of partnerships. To understand PPPs a multi-disciplinary perspective that draws on insights from social theory is needed. This paper demonstrates how social theory can aid the understanding of the complex relationships of actors involved in implementation of Public-Private Mix (PPM)-TB policy in India. Ethnographic research was conducted within a district in a Southern state of India over a 14 month period, combining participant observations, informal interactions and in-depth interviews with a wide range of respondents across public, private and non-government organisation (NGO) sectors. Drawing on the theoretical insights from Bourdieu's "theory of practice" this study explores the relationships between the different actors. The study found that programme managers, frontline TB workers, NGOs, and private practitioners all had a crucial role to play in TB partnerships. They were widely regarded as valued contributors with distinct social skills and capabilities within their organizations and professions. However, their potential contributions towards programme implementation tended to be unrecognized both at the top and bottom of the policy implementation chain. These actors constantly struggled for recognition and used different mechanisms to position themselves alongside other actors within the programme that further complicated the relationships between different actors. This paper demonstrates that applying social theory can enable a better understanding of the complex relationship

  7. Network location theory and contingency planning

    Energy Technology Data Exchange (ETDEWEB)

    Hakimi, S L

    1983-08-01

    A brief survey of results in network location theory is first presented. Then, a systems view of contingency planning is described. Finally, some results in location theory are re-examined and it is shown that they are motivated by contingency planning considerations. Some new issues and problems in location theory are described, which, if properly tackled, will have a substantial impact on contingency planning in transportation.

  8. Remarks on network public theory

    OpenAIRE

    Marcin Brol; Slawomir Czetwertynski

    2013-01-01

    This paper is a trial of capturing of a relation between traditional public sphere atrophy and the augmentation of a network public sphere. A thesis is advanced that the traditional public sphere is subject of the atrophy, however, the entire network public sphere is subject of the augmentation process. Such a formulated thesis forces a choice between two following issues. The first of them regards a relation between factors, which stimulate the atrophy and the augmentation. The second issue ...

  9. A first course in network theory

    CERN Document Server

    Estrada, Ernesto

    2015-01-01

    The study of network theory is a highly interdisciplinary field, which has emerged as a major topic of interest in various disciplines ranging from physics and mathematics, to biology and sociology. This book promotes the diverse nature of the study of complex networks by balancing the needs of students from very different backgrounds. It references the most commonly used concepts in network theory, provides examples of their applications in solving practicalproblems, and clear indications on how to analyse their results.In the first part of the book, students and researchers will discover the

  10. Mathematical theories of distributed sensor networks

    CERN Document Server

    Iyengar, Sitharama S; Balakrishnan, N

    2014-01-01

    Mathematical Theory of Distributed Sensor Networks demonstrates how mathematical theories can be used to provide distributed sensor modeling and to solve important problems such as coverage hole detection and repair. The book introduces the mathematical and computational structure by discussing what they are, their applications and how they differ from traditional systems. The text also explains how mathematics are utilized to provide efficient techniques implementing effective coverage, deployment, transmission, data processing, signal processing, and data protection within distributed sensor networks. Finally, the authors discuss some important challenges facing mathematics to get more incite to the multidisciplinary area of distributed sensor networks.

  11. COalitions in COOperation Networks (COCOON): Social Network Analysis and Game Theory to Enhance Cooperation Networks

    NARCIS (Netherlands)

    Sie, Rory

    2012-01-01

    Sie, R. L. L. (2012). COalitions in COOperation Networks (COCOON): Social Network Analysis and Game Theory to Enhance Cooperation Networks (Unpublished doctoral dissertation). September, 28, 2012, Open Universiteit in the Netherlands (CELSTEC), Heerlen, The Netherlands.

  12. Graphical Model Theory for Wireless Sensor Networks

    International Nuclear Information System (INIS)

    Davis, William B.

    2002-01-01

    Information processing in sensor networks, with many small processors, demands a theory of computation that allows the minimization of processing effort, and the distribution of this effort throughout the network. Graphical model theory provides a probabilistic theory of computation that explicitly addresses complexity and decentralization for optimizing network computation. The junction tree algorithm, for decentralized inference on graphical probability models, can be instantiated in a variety of applications useful for wireless sensor networks, including: sensor validation and fusion; data compression and channel coding; expert systems, with decentralized data structures, and efficient local queries; pattern classification, and machine learning. Graphical models for these applications are sketched, and a model of dynamic sensor validation and fusion is presented in more depth, to illustrate the junction tree algorithm

  13. Application of actor level social characteristic indicator selection for the precursory detection of bullies in online social networks

    Science.gov (United States)

    White, Holly M.; Fields, Jeremy; Hall, Robert T.; White, Joshua S.

    2016-05-01

    Bullying is a national problem for families, courts, schools, and the economy. Social, educational, and professional lives of victims are affected. Early detection of bullies mitigates destructive effects of bullying. Our previous research found, given specific characteristics of an actor, actor logics can be developed utilizing input from natural language processing and graph analysis. Given similar characteristics of cyberbullies, in this paper, we create specific actor logics and apply these to a select social media dataset for the purpose of rapid identification of cyberbullying.

  14. Information theory perspective on network robustness

    International Nuclear Information System (INIS)

    Schieber, Tiago A.; Carpi, Laura; Frery, Alejandro C.; Rosso, Osvaldo A.; Pardalos, Panos M.; Ravetti, Martín G.

    2016-01-01

    A crucial challenge in network theory is the study of the robustness of a network when facing a sequence of failures. In this work, we propose a dynamical definition of network robustness based on Information Theory, that considers measurements of the structural changes caused by failures of the network's components. Failures are defined here as a temporal process defined in a sequence. Robustness is then evaluated by measuring dissimilarities between topologies after each time step of the sequence, providing a dynamical information about the topological damage. We thoroughly analyze the efficiency of the method in capturing small perturbations by considering different probability distributions on networks. In particular, we find that distributions based on distances are more consistent in capturing network structural deviations, as better reflect the consequences of the failures. Theoretical examples and real networks are used to study the performance of this methodology. - Highlights: • A novel methodology to measure the robustness of a network to component failure or targeted attacks is proposed. • The use of the network's distance PDF allows a precise analysis. • The method provides a dynamic robustness profile showing the response of the topology to each failure event. • The measure is capable to detect network's critical elements.

  15. Network Security Validation Using Game Theory

    Science.gov (United States)

    Papadopoulou, Vicky; Gregoriades, Andreas

    Non-functional requirements (NFR) such as network security recently gained widespread attention in distributed information systems. Despite their importance however, there is no systematic approach to validate these requirements given the complexity and uncertainty characterizing modern networks. Traditionally, network security requirements specification has been the results of a reactive process. This however, limited the immunity property of the distributed systems that depended on these networks. Security requirements specification need a proactive approach. Networks' infrastructure is constantly under attack by hackers and malicious software that aim to break into computers. To combat these threats, network designers need sophisticated security validation techniques that will guarantee the minimum level of security for their future networks. This paper presents a game-theoretic approach to security requirements validation. An introduction to game theory is presented along with an example that demonstrates the application of the approach.

  16. Fuzzy neural network theory and application

    CERN Document Server

    Liu, Puyin

    2004-01-01

    This book systematically synthesizes research achievements in the field of fuzzy neural networks in recent years. It also provides a comprehensive presentation of the developments in fuzzy neural networks, with regard to theory as well as their application to system modeling and image restoration. Special emphasis is placed on the fundamental concepts and architecture analysis of fuzzy neural networks. The book is unique in treating all kinds of fuzzy neural networks and their learning algorithms and universal approximations, and employing simulation examples which are carefully designed to he

  17. Psychology and social networks: a dynamic network theory perspective.

    Science.gov (United States)

    Westaby, James D; Pfaff, Danielle L; Redding, Nicholas

    2014-04-01

    Research on social networks has grown exponentially in recent years. However, despite its relevance, the field of psychology has been relatively slow to explain the underlying goal pursuit and resistance processes influencing social networks in the first place. In this vein, this article aims to demonstrate how a dynamic network theory perspective explains the way in which social networks influence these processes and related outcomes, such as goal achievement, performance, learning, and emotional contagion at the interpersonal level of analysis. The theory integrates goal pursuit, motivation, and conflict conceptualizations from psychology with social network concepts from sociology and organizational science to provide a taxonomy of social network role behaviors, such as goal striving, system supporting, goal preventing, system negating, and observing. This theoretical perspective provides psychologists with new tools to map social networks (e.g., dynamic network charts), which can help inform the development of change interventions. Implications for social, industrial-organizational, and counseling psychology as well as conflict resolution are discussed, and new opportunities for research are highlighted, such as those related to dynamic network intelligence (also known as cognitive accuracy), levels of analysis, methodological/ethical issues, and the need to theoretically broaden the study of social networking and social media behavior. (PsycINFO Database Record (c) 2014 APA, all rights reserved).

  18. "Securing our survival (SOS": non-state actors and the campaign for a nuclear weapons convention through the prism of securitisation theory

    Directory of Open Access Journals (Sweden)

    Renata H. Dalaqua

    2013-12-01

    Full Text Available This article analyses the security practices of the anti-nuclear movement in the post-Cold War period through the prism of securitisation theory. By exploring Buzan and Wæver's conceptual developments on macrosecuritisations, the practices involved in the struggle against the Bomb are interpreted as securitising moves, in which the anti-nuclear movement is the leading securitiser. In the capacity of securitising actors, nuclear abolition activists argue that nuclear disarmament, under a Nuclear Weapons Convention (NWC, would be the only way to protect humankind from the threat posed by the existence of nuclear weapons. The empirical analysis of these non-state actors and their campaign for a NWC shows that, despite uttering security, the anti-nuclear movement has so far failed to achieve the proposed security measure, that is, nuclear disarmament. Nonetheless, securitisation has been instrumental for these non-state actors as a way of raising an issue on the agenda of decision-makers and urging them to take action.

  19. Linear control theory for gene network modeling.

    Science.gov (United States)

    Shin, Yong-Jun; Bleris, Leonidas

    2010-09-16

    Systems biology is an interdisciplinary field that aims at understanding complex interactions in cells. Here we demonstrate that linear control theory can provide valuable insight and practical tools for the characterization of complex biological networks. We provide the foundation for such analyses through the study of several case studies including cascade and parallel forms, feedback and feedforward loops. We reproduce experimental results and provide rational analysis of the observed behavior. We demonstrate that methods such as the transfer function (frequency domain) and linear state-space (time domain) can be used to predict reliably the properties and transient behavior of complex network topologies and point to specific design strategies for synthetic networks.

  20. Towards an Information Theory of Complex Networks

    CERN Document Server

    Dehmer, Matthias; Mehler, Alexander

    2011-01-01

    For over a decade, complex networks have steadily grown as an important tool across a broad array of academic disciplines, with applications ranging from physics to social media. A tightly organized collection of carefully-selected papers on the subject, Towards an Information Theory of Complex Networks: Statistical Methods and Applications presents theoretical and practical results about information-theoretic and statistical models of complex networks in the natural sciences and humanities. The book's major goal is to advocate and promote a combination of graph-theoretic, information-theoreti

  1. The roles of actors in the host society in the integration of inmigrants associations: a social networks analysis approach

    Directory of Open Access Journals (Sweden)

    José Manuel Gaete Fiscella

    2016-06-01

    Full Text Available This article explores the stages of integration of immigrant associations in Spain according to stock of social capital, specifically, given the relationships established with actors in the environment, and consequently this role is derived for each type of counterpart. The data are drawn from a representative sample consisting of 225 immigrant associations around the country. The results suggest that immigrant associations play cohesive and specific roles with their peers, even achieve certain asymmetries in their favor with certain actors in the host society. On the other hand, native actors host society are distributed in a continuum ranging from the development of specific roles to other multiple, and even contradictory, which, as a whole, ends up drawing a map of complex and diverse opportunities for integration of associations.

  2. Dobrushin's approach to queueing network theory

    Directory of Open Access Journals (Sweden)

    F. I. Karpelevich

    1996-01-01

    Full Text Available R.L. Dobrushin (1929-1995 made substantial contributions to Queueing Network Theory (QNT. A review of results from QNT which arose from his ideas or were connected to him in other ways is given. We also comment on various related open problems.

  3. Nonequilibrium landscape theory of neural networks.

    Science.gov (United States)

    Yan, Han; Zhao, Lei; Hu, Liang; Wang, Xidi; Wang, Erkang; Wang, Jin

    2013-11-05

    The brain map project aims to map out the neuron connections of the human brain. Even with all of the wirings mapped out, the global and physical understandings of the function and behavior are still challenging. Hopfield quantified the learning and memory process of symmetrically connected neural networks globally through equilibrium energy. The energy basins of attractions represent memories, and the memory retrieval dynamics is determined by the energy gradient. However, the realistic neural networks are asymmetrically connected, and oscillations cannot emerge from symmetric neural networks. Here, we developed a nonequilibrium landscape-flux theory for realistic asymmetrically connected neural networks. We uncovered the underlying potential landscape and the associated Lyapunov function for quantifying the global stability and function. We found the dynamics and oscillations in human brains responsible for cognitive processes and physiological rhythm regulations are determined not only by the landscape gradient but also by the flux. We found that the flux is closely related to the degrees of the asymmetric connections in neural networks and is the origin of the neural oscillations. The neural oscillation landscape shows a closed-ring attractor topology. The landscape gradient attracts the network down to the ring. The flux is responsible for coherent oscillations on the ring. We suggest the flux may provide the driving force for associations among memories. We applied our theory to rapid-eye movement sleep cycle. We identified the key regulation factors for function through global sensitivity analysis of landscape topography against wirings, which are in good agreements with experiments.

  4. Nonequilibrium landscape theory of neural networks

    Science.gov (United States)

    Yan, Han; Zhao, Lei; Hu, Liang; Wang, Xidi; Wang, Erkang; Wang, Jin

    2013-01-01

    The brain map project aims to map out the neuron connections of the human brain. Even with all of the wirings mapped out, the global and physical understandings of the function and behavior are still challenging. Hopfield quantified the learning and memory process of symmetrically connected neural networks globally through equilibrium energy. The energy basins of attractions represent memories, and the memory retrieval dynamics is determined by the energy gradient. However, the realistic neural networks are asymmetrically connected, and oscillations cannot emerge from symmetric neural networks. Here, we developed a nonequilibrium landscape–flux theory for realistic asymmetrically connected neural networks. We uncovered the underlying potential landscape and the associated Lyapunov function for quantifying the global stability and function. We found the dynamics and oscillations in human brains responsible for cognitive processes and physiological rhythm regulations are determined not only by the landscape gradient but also by the flux. We found that the flux is closely related to the degrees of the asymmetric connections in neural networks and is the origin of the neural oscillations. The neural oscillation landscape shows a closed-ring attractor topology. The landscape gradient attracts the network down to the ring. The flux is responsible for coherent oscillations on the ring. We suggest the flux may provide the driving force for associations among memories. We applied our theory to rapid-eye movement sleep cycle. We identified the key regulation factors for function through global sensitivity analysis of landscape topography against wirings, which are in good agreements with experiments. PMID:24145451

  5. Formulation and applications of complex network theory

    Science.gov (United States)

    Park, Juyong

    In recent years, there has been a great surge of interest among physicists in modeling social, technological, or biological systems as networks. Analyses of large-scale networks such as the Internet have led to discoveries of many unexpected network properties, including power-law degree distributions. These discoveries have prompted physicists to devise novel ways to model networks, both computational and theoretical. In this dissertation, we present several network models and their applications. First, we study the theory of Exponential Random Graphs. We derive it from the principle of maximum entropy, thereby showing that it is the equivalent of the Gibbs ensemble for networks. Using tools of statistical physics, we solve well-known and new examples that include power-law networks and the two-star model. Our solutions confirm the existence of a first-order phase transition for the latter whose exact behavior has not been presented previously. We also study degree correlations and clustering in networks. Degrees of adjacent vertices are positively correlated in social networks, whereas they are negatively correlated in other types of networks. We demonstrate that a negative degree correlation is a more natural state of a network, and therefore that social networks are an exception. We argue that variations in the number of vertices in social groups cause positive degree correlations, and analyze a model that incorporates such a mechanism. The model indeed shows a high level of degree correlation and clustering that is similar in value to those of real networks. Finally, we develop algorithms for ranking vertices in networks that represent pairwise comparisons. The first algorithm is based on the familiar concept of indirect wins and losses. The second algorithm is based on the concept of retrodictive accuracy, which is maximized by positioning as many winners above the losers as possible. We compare the rankings of American college football teams generated by our

  6. Understanding responsible innovation in small producers’ clusters in Vietnam through Actor Network Theory (ANT)

    NARCIS (Netherlands)

    Voeten, J.; de Haan, J.A.C.; Roome, N.; de Groot, G.A.

    Innovation is increasingly recognised as an alternative for poverty alleviation in developing countries. However, cases of innovation in small producers’ clusters in Vietnam imply negative externalities that conflict with today’s notions of sustainable and inclusive development. This article

  7. Technologies for Learning? An Actor-Network Theory Critique of "Affordances" in Research on Mobile Learning

    Science.gov (United States)

    Wright, Steve; Parchoma, Gale

    2011-01-01

    How is the link between learner and technology made in mobile learning? What is the value of the concept of "affordances"? And how does research articulating this concept act to position mobile devices as "technologies for learning"? This literature review used both unstructured and structured search samples of published research on mobile…

  8. The Photograph as Network

    DEFF Research Database (Denmark)

    Wiegand, Frauke Katharina

    2017-01-01

    Inspired by actor-network theory (ANT), this article develops a theoretical framework to grasp the dynamic visual work of memory. It introduces three sensitizing concepts of actor-network methodology, namely entanglement, relationality and traceability, and operationalizes them in a methodological...

  9. Linear control theory for gene network modeling.

    Directory of Open Access Journals (Sweden)

    Yong-Jun Shin

    Full Text Available Systems biology is an interdisciplinary field that aims at understanding complex interactions in cells. Here we demonstrate that linear control theory can provide valuable insight and practical tools for the characterization of complex biological networks. We provide the foundation for such analyses through the study of several case studies including cascade and parallel forms, feedback and feedforward loops. We reproduce experimental results and provide rational analysis of the observed behavior. We demonstrate that methods such as the transfer function (frequency domain and linear state-space (time domain can be used to predict reliably the properties and transient behavior of complex network topologies and point to specific design strategies for synthetic networks.

  10. Examining actors into boosting the provision of universal service in the Vietnamese context

    DEFF Research Database (Denmark)

    Do Manh, Thai; Williams, Idongesit

    2017-01-01

    are very important in formulating and implementing universal service policy. Originality/value - There have been a few studies applying actor network theory in analysing the formulation of policy, especially in universal service. The paper wants to close this gap.......Purpose - The paper looks at the formulation of the BMGF-VN project to examine which actors participated in the formulation of this project, how their interests were translated into this project, and what lessons may be drawn for the formulation and implementation of universal service policy...... in Vietnam in general. Design/methodology/approach - The paper recruits the actor network theory and qualitative analysis to analyse the BMGF-VN project. Findings - the involvement of non-government actors in formulating and implementing the project, the focus not only on the supply side but also demand side...

  11. Research on Evolutionary Mechanism of Agile Supply Chain Network via Complex Network Theory

    Directory of Open Access Journals (Sweden)

    Nai-Ru Xu

    2016-01-01

    Full Text Available The paper establishes the evolutionary mechanism model of agile supply chain network by means of complex network theory which can be used to describe the growth process of the agile supply chain network and analyze the complexity of the agile supply chain network. After introducing the process and the suitability of taking complex network theory into supply chain network research, the paper applies complex network theory into the agile supply chain network research, analyzes the complexity of agile supply chain network, presents the evolutionary mechanism of agile supply chain network based on complex network theory, and uses Matlab to simulate degree distribution, average path length, clustering coefficient, and node betweenness. Simulation results show that the evolution result displays the scale-free property. It lays the foundations of further research on agile supply chain network based on complex network theory.

  12. Moving from theory to practice: A participatory social network mapping approach to address unmet need for family planning in Benin.

    Science.gov (United States)

    Igras, Susan; Diakité, Mariam; Lundgren, Rebecka

    2017-07-01

    In West Africa, social factors influence whether couples with unmet need for family planning act on birth-spacing desires. Tékponon Jikuagou is testing a social network-based intervention to reduce social barriers by diffusing new ideas. Individuals and groups judged socially influential by their communities provide entrée to networks. A participatory social network mapping methodology was designed to identify these diffusion actors. Analysis of monitoring data, in-depth interviews, and evaluation reports assessed the methodology's acceptability to communities and staff and whether it produced valid, reliable data to identify influential individuals and groups who diffuse new ideas through their networks. Results indicated the methodology's acceptability. Communities were actively and equitably engaged. Staff appreciated its ability to yield timely, actionable information. The mapping methodology also provided valid and reliable information by enabling communities to identify highly connected and influential network actors. Consistent with social network theory, this methodology resulted in the selection of informal groups and individuals in both informal and formal positions. In-depth interview data suggest these actors were diffusing new ideas, further confirming their influence/connectivity. The participatory methodology generated insider knowledge of who has social influence, challenging commonly held assumptions. Collecting and displaying information fostered staff and community learning, laying groundwork for social change.

  13. Wireless sensor networks from theory to applications

    CERN Document Server

    El Emary, Ibrahiem M M

    2013-01-01

    Although there are many books available on WSNs, most are low-level, introductory books. The few available for advanced readers fail to convey the breadth of knowledge required for those aiming to develop next-generation solutions for WSNs. Filling this void, Wireless Sensor Networks: From Theory to Applications supplies comprehensive coverage of WSNs. In order to provide the wide-ranging guidance required, the book brings together the contributions of domain experts working in the various subfields of WSNs worldwide. This edited volume examines recent advances in WSN technologies and consider

  14. Game theory in communication networks cooperative resolution of interactive networking scenarios

    CERN Document Server

    Antoniou, Josephina

    2012-01-01

    A mathematical tool for scientists and researchers who work with computer and communication networks, Game Theory in Communication Networks: Cooperative Resolution of Interactive Networking Scenarios addresses the question of how to promote cooperative behavior in interactive situations between heterogeneous entities in communication networking scenarios. It explores network design and management from a theoretical perspective, using game theory and graph theory to analyze strategic situations and demonstrate profitable behaviors of the cooperative entities. The book promotes the use of Game T

  15. EUBIONET II. Efficient trading of biomass fuels and analysis of fuel supply chains and business models for market actors by networking. Final result-oriented report

    Energy Technology Data Exchange (ETDEWEB)

    Alakangas, E.; Wiik, C.; Vesterinen, P. (and others)

    2008-02-15

    The project aimed to increase deployment of biomass fuels into European market and match technology uptake by means of market and policy analysis and other well-defined tasks to meet European policy targets in renewable energy sector. The project is to result as increased use of biomass fuels and market uptake of innovative bioenergy technologies. The objectives of the project were the following: 1) To give a clear outlook on current and future biomass fuel market trends. 2) To give feedback on the suitability of CEN 335 biofuel standard for trading of solid biofuels. 3) To provide well-analysed estimation on techno-economic potential of the biomass fuel volumes until 2010 based on the existing studies and experts opinions. Regarding the forest biomass sector, co-operation will be done with forest industry stakeholders to find proper balance between forest industry raw material and bioenergy usage. 4) To enhance biomass fuel trade and technology transfer by networking among different actors. 5) To analyse, select and describe the most suitable trading and business models for small- and largescale biofuel supply chains for heat and power production by taking into account the environmental aspects and sustainability. 6) To enhance biomass usage by the means of co-operation and information dissemination among different market actors in the fuel-utilisation chain. Target groups were biomass fuel traders and users, fuel producers and suppliers of different scales, policy makers in both current and new member states. Key associations, i.e. AEBIOM and CEPI, were participating in the project and disseminating information to various groups. The project has been structured in 5 workpackages. Project was carried out by 16 partners, which are the key national bioenergy organisations in the European countries and have a long co-operation relationship in previous bioenergy networks. The project has published summary reports and national report of each WP and this report is

  16. The Economics of Networks: theory and empirics

    NARCIS (Netherlands)

    M.J. van der Leij (Marco)

    2006-01-01

    textabstractWherever we are, networks are all around us. The roads that we travel form a network. The websites that we visit form an enormous information network. But, above all, we are part of a network ourselves, the network of social contacts and relations. These networks play an

  17. Networking of theories as a research practice in mathematics education

    CERN Document Server

    Bikner-Ahsbahs, Angelika

    2014-01-01

    How can we deal with the diversity of theories in mathematics education This was the main question that led the authors of this book to found the Networking Theories Group. Starting from the shared assumption that the existence of different theories is a resource for mathematics education research, the authors have explored the possibilities of interactions between theories, such as contrasting, coordinating, and locally integrating them. The book explains and illustrates what it means to network theories; it presents networking as a challenging but fruitful research practice and shows how the Group dealt with this challenge considering five theoretical approaches, namely the approach of Action, Production, and Communication (APC), the Theory of Didactical Situations (TDS), the Anthropological Theory of the Didactic (ATD), the approach of Abstraction in Context (AiC), and the Theory of Interest-Dense Situations (IDS). A synthetic presentation of each theory and their connections shows how the activity of netw...

  18. How Might Better Network Theories Support School Leadership Research?

    Science.gov (United States)

    Hadfield, Mark; Jopling, Michael

    2012-01-01

    This article explores how recent research in education has applied different aspects of "network" theory to the study of school leadership. Constructs from different network theories are often used because of their perceived potential to clarify two perennial issues in leadership research. The first is the relative importance of formal and…

  19. Understanding Social Networks: Theories, Concepts, and Findings

    Science.gov (United States)

    Kadushin, Charles

    2012-01-01

    Despite the swift spread of social network concepts and their applications and the rising use of network analysis in social science, there is no book that provides a thorough general introduction for the serious reader. "Understanding Social Networks" fills that gap by explaining the big ideas that underlie the social network phenomenon.…

  20. Adaptive Networks Theory, Models and Applications

    CERN Document Server

    Gross, Thilo

    2009-01-01

    With adaptive, complex networks, the evolution of the network topology and the dynamical processes on the network are equally important and often fundamentally entangled. Recent research has shown that such networks can exhibit a plethora of new phenomena which are ultimately required to describe many real-world networks. Some of those phenomena include robust self-organization towards dynamical criticality, formation of complex global topologies based on simple, local rules, and the spontaneous division of "labor" in which an initially homogenous population of network nodes self-organizes into functionally distinct classes. These are just a few. This book is a state-of-the-art survey of those unique networks. In it, leading researchers set out to define the future scope and direction of some of the most advanced developments in the vast field of complex network science and its applications.

  1. A Preliminary Theory of Dark Network Resilience

    Science.gov (United States)

    Bakker, Rene M.; Raab, Jorg; Milward, H. Brinton

    2012-01-01

    A crucial contemporary policy question for governments across the globe is how to cope with international crime and terrorist networks. Many such "dark" networks--that is, networks that operate covertly and illegally--display a remarkable level of resilience when faced with shocks and attacks. Based on an in-depth study of three cases…

  2. Essays on Networks: Theory and Applications

    NARCIS (Netherlands)

    A.M. Babus (Ana Maria)

    2008-01-01

    textabstractNetworks have proven to be a useful representation of various systems. Social and economic interactions, biological and ecological systems, the internet can be understood better if modelled as networks. Intuitively, a network describes a collection of nodes and the links between them.

  3. Determinants of Actor Rationality

    DEFF Research Database (Denmark)

    Ellegaard, Chris

    Industrial companies must exercise influence on their suppliers (or supplier actors). Actor rationality is a central theme connected to this management task. In this article, relevant literature is studied with the purpose of shedding light on determinants of actor rationality. Two buyer-supplier...... relations are investigated in a multiple case study, leading to the proposal of various additional factors that determine and shape actor rationality. Moreover a conceptual model of rationality determinants in the buyer-supplier relation is proposed, a model that may help supply managers analyse...

  4. Moral actor, selfish agent.

    Science.gov (United States)

    Frimer, Jeremy A; Schaefer, Nicola K; Oakes, Harrison

    2014-05-01

    People are motivated to behave selfishly while appearing moral. This tension gives rise to 2 divergently motivated selves. The actor-the watched self-tends to be moral; the agent-the self as executor-tends to be selfish. Three studies present direct evidence of the actor's and agent's distinct motives. To recruit the self-as-actor, we asked people to rate the importance of various goals. To recruit the self-as-agent, we asked people to describe their goals verbally. In Study 1, actors claimed their goals were equally about helping the self and others (viz., moral); agents claimed their goals were primarily about helping the self (viz., selfish). This disparity was evident in both individualist and collectivist cultures, attesting to the universality of the selfish agent. Study 2 compared actors' and agents' motives to those of people role-playing highly prosocial or selfish exemplars. In content (Study 2a) and in the impressions they made on an outside observer (Study 2b), actors' motives were similar to those of the prosocial role-players, whereas agents' motives were similar to those of the selfish role-players. Study 3 accounted for the difference between the actor and agent: Participants claimed that their agent's motives were the more realistic and that their actor's motives were the more idealistic. The selfish agent/moral actor duality may account for why implicit and explicit measures of the same construct diverge, and why feeling watched brings out the better angels of human nature.

  5. Application of random matrix theory to biological networks

    Energy Technology Data Exchange (ETDEWEB)

    Luo Feng [Department of Computer Science, Clemson University, 100 McAdams Hall, Clemson, SC 29634 (United States); Department of Pathology, U.T. Southwestern Medical Center, 5323 Harry Hines Blvd. Dallas, TX 75390-9072 (United States); Zhong Jianxin [Department of Physics, Xiangtan University, Hunan 411105 (China) and Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States)]. E-mail: zhongjn@ornl.gov; Yang Yunfeng [Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States); Scheuermann, Richard H. [Department of Pathology, U.T. Southwestern Medical Center, 5323 Harry Hines Blvd. Dallas, TX 75390-9072 (United States); Zhou Jizhong [Department of Botany and Microbiology, University of Oklahoma, Norman, OK 73019 (United States) and Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States)]. E-mail: zhouj@ornl.gov

    2006-09-25

    We show that spectral fluctuation of interaction matrices of a yeast protein-protein interaction network and a yeast metabolic network follows the description of the Gaussian orthogonal ensemble (GOE) of random matrix theory (RMT). Furthermore, we demonstrate that while the global biological networks evaluated belong to GOE, removal of interactions between constituents transitions the networks to systems of isolated modules described by the Poisson distribution. Our results indicate that although biological networks are very different from other complex systems at the molecular level, they display the same statistical properties at network scale. The transition point provides a new objective approach for the identification of functional modules.

  6. Network analysis and synthesis a modern systems theory approach

    CERN Document Server

    Anderson, Brian D O

    2006-01-01

    Geared toward upper-level undergraduates and graduate students, this book offers a comprehensive look at linear network analysis and synthesis. It explores state-space synthesis as well as analysis, employing modern systems theory to unite the classical concepts of network theory. The authors stress passive networks but include material on active networks. They avoid topology in dealing with analysis problems and discuss computational techniques. The concepts of controllability, observability, and degree are emphasized in reviewing the state-variable description of linear systems. Explorations

  7. The political history of biofuels in the European Union - Actors, Networks and Strategies; Den politiska historien om biodrivmedel i den Europeiska Unionen - Aktoerer, naetverk och strategier

    Energy Technology Data Exchange (ETDEWEB)

    Nordangaard, Jacob

    2012-07-01

    The story of biofuels in the European Union is about much more than simply replace petroleum in the transport sector. It is rather a complex story accompanied by an overall desire to change the world's political architecture. This change has been made in order to address global environmental problems such as climate change while creating frameworks and certifications for the global trade in commodities such as palm oil and soy. The process has been full of contradictions in what biofuels can solve and given rise to exaggerated rhetoric about the fuel's environmental benefits versus its harmful impact on the environment and food prices. Doomsday reeking arguments about climate disasters, oil shortages and the destruction of the world's rain forests have been used alternately in diverse contexts. In this process, various market interests have come to stand against each other in the battle for the raw materials used in biofuel production. Good intentions to protect the priceless nature from industrial exploitation has been used as a way to disadvantage certain raw materials as an energy crop. This has given rise to the unholy alliances between environmentalists and corporations to create broad support for positions while individual nations have assisted with capital and resources to promote various self-interests. In the end it has been a matter of building so powerful network as possible, and present a hard hitting problem requiring a solution for success. Out of chaos, it has been born order. This thesis describes the process and the main actors and networks that have driven this.

  8. Analysing collaboration among HIV agencies through combining network theory and relational coordination.

    Science.gov (United States)

    Khosla, Nidhi; Marsteller, Jill Ann; Hsu, Yea Jen; Elliott, David L

    2016-02-01

    Agencies with different foci (e.g. nutrition, social, medical, housing) serve people living with HIV (PLHIV). Serving needs of PLHIV comprehensively requires a high degree of coordination among agencies which often benefits from more frequent communication. We combined Social Network theory and Relational Coordination theory to study coordination among HIV agencies in Baltimore. Social Network theory implies that actors (e.g., HIV agencies) establish linkages amongst themselves in order to access resources (e.g., information). Relational Coordination theory suggests that high quality coordination among agencies or teams relies on the seven dimensions of frequency, timeliness and accuracy of communication, problem-solving communication, knowledge of agencies' work, mutual respect and shared goals. We collected data on frequency of contact from 57 agencies using a roster method. Response options were ordinal ranging from 'not at all' to 'daily'. We analyzed data using social network measures. Next, we selected agencies with which at least one-third of the sample reported monthly or more frequent interaction. This yielded 11 agencies whom we surveyed on seven relational coordination dimensions with questions scored on a Likert scale of 1-5. Network density, defined as the proportion of existing connections to all possible connections, was 20% when considering monthly or higher interaction. Relational coordination scores from individual agencies to others ranged between 1.17 and 5.00 (maximum possible score 5). The average scores for different dimensions across all agencies ranged between 3.30 and 4.00. Shared goals (4.00) and mutual respect (3.91) scores were highest, while scores such as knowledge of each other's work and problem-solving communication were relatively lower. Combining theoretically driven analyses in this manner offers an innovative way to provide a comprehensive picture of inter-agency coordination and the quality of exchange that underlies

  9. Modern temporal network theory: a colloquium

    Science.gov (United States)

    Holme, Petter

    2015-09-01

    The power of any kind of network approach lies in the ability to simplify a complex system so that one can better understand its function as a whole. Sometimes it is beneficial, however, to include more information than in a simple graph of only nodes and links. Adding information about times of interactions can make predictions and mechanistic understanding more accurate. The drawback, however, is that there are not so many methods available, partly because temporal networks is a relatively young field, partly because it is more difficult to develop such methods compared to for static networks. In this colloquium, we review the methods to analyze and model temporal networks and processes taking place on them, focusing mainly on the last three years. This includes the spreading of infectious disease, opinions, rumors, in social networks; information packets in computer networks; various types of signaling in biology, and more. We also discuss future directions.

  10. Ad hoc networks telecommunications and game theory

    CERN Document Server

    Benslama, Malek; Batatia, Hadj

    2015-01-01

    Random SALOHA and CSMA protocols that are used to access MAC in ad hoc networks are very small compared to the multiple and spontaneous use of the transmission channel. So they have low immunity to the problems of packet collisions. Indeed, the transmission time is the critical factor in the operation of such networks. The simulations demonstrate the positive impact of erasure codes on the throughput of the transmission in ad hoc networks. However, the network still suffers from the intermittency and volatility of its efficiency throughout its operation, and it switches quickly to the satura

  11. Control theory of digitally networked dynamic systems

    CERN Document Server

    Lunze, Jan

    2013-01-01

    The book gives an introduction to networked control systems and describes new modeling paradigms, analysis methods for event-driven, digitally networked systems, and design methods for distributed estimation and control. Networked model predictive control is developed as a means to tolerate time delays and packet loss brought about by the communication network. In event-based control the traditional periodic sampling is replaced by state-dependent triggering schemes. Novel methods for multi-agent systems ensure complete or clustered synchrony of agents with identical or with individual dynamic

  12. Renormalization group theory for percolation in time-varying networks.

    Science.gov (United States)

    Karschau, Jens; Zimmerling, Marco; Friedrich, Benjamin M

    2018-05-22

    Motivated by multi-hop communication in unreliable wireless networks, we present a percolation theory for time-varying networks. We develop a renormalization group theory for a prototypical network on a regular grid, where individual links switch stochastically between active and inactive states. The question whether a given source node can communicate with a destination node along paths of active links is equivalent to a percolation problem. Our theory maps the temporal existence of multi-hop paths on an effective two-state Markov process. We show analytically how this Markov process converges towards a memoryless Bernoulli process as the hop distance between source and destination node increases. Our work extends classical percolation theory to the dynamic case and elucidates temporal correlations of message losses. Quantification of temporal correlations has implications for the design of wireless communication and control protocols, e.g. in cyber-physical systems such as self-organized swarms of drones or smart traffic networks.

  13. The cooperative game theory of networks and hierarchies

    CERN Document Server

    Gilles, Robert P

    2010-01-01

    This book details standard concepts in cooperative game theory with applications to the analysis of social networks and hierarchical authority organizations. It covers the multi-linear extension, the Core, the Shapley value, and the cooperative potential.

  14. A preliminary theory of dark network resilience

    NARCIS (Netherlands)

    Bakker, R.M.; Raab, J.; Milward, H.B.

    2012-01-01

    A crucial contemporary policy question for governments across the globe is how to cope with international crime and terrorist networks. Many such “dark” networks—that is, networks that operate covertly and illegally—display a remarkable level of resilience when faced with shocks and attacks. Based

  15. Detection of network attacks based on adaptive resonance theory

    Science.gov (United States)

    Bukhanov, D. G.; Polyakov, V. M.

    2018-05-01

    The paper considers an approach to intrusion detection systems using a neural network of adaptive resonant theory. It suggests the structure of an intrusion detection system consisting of two types of program modules. The first module manages connections of user applications by preventing the undesirable ones. The second analyzes the incoming network traffic parameters to check potential network attacks. After attack detection, it notifies the required stations using a secure transmission channel. The paper describes the experiment on the detection and recognition of network attacks using the test selection. It also compares the obtained results with similar experiments carried out by other authors. It gives findings and conclusions on the sufficiency of the proposed approach. The obtained information confirms the sufficiency of applying the neural networks of adaptive resonant theory to analyze network traffic within the intrusion detection system.

  16. Neutral theory of chemical reaction networks

    International Nuclear Information System (INIS)

    Lee, Sang Hoon; Holme, Petter; Minnhagen, Petter; Bernhardsson, Sebastian; Kim, Beom Jun

    2012-01-01

    To what extent do the characteristic features of a chemical reaction network reflect its purpose and function? In general, one argues that correlations between specific features and specific functions are key to understanding a complex structure. However, specific features may sometimes be neutral and uncorrelated with any system-specific purpose, function or causal chain. Such neutral features are caused by chance and randomness. Here we compare two classes of chemical networks: one that has been subjected to biological evolution (the chemical reaction network of metabolism in living cells) and one that has not (the atmospheric planetary chemical reaction networks). Their degree distributions are shown to share the very same neutral system-independent features. The shape of the broad distributions is to a large extent controlled by a single parameter, the network size. From this perspective, there is little difference between atmospheric and metabolic networks; they are just different sizes of the same random assembling network. In other words, the shape of the degree distribution is a neutral characteristic feature and has no functional or evolutionary implications in itself; it is not a matter of life and death. (paper)

  17. Social Capital Theory: Implications for Women's Networking and Learning

    Science.gov (United States)

    Alfred, Mary V.

    2009-01-01

    This chapter describes social capital theory as a framework for exploring women's networking and social capital resources. It presents the foundational assumptions of the theory, the benefits and risks of social capital engagement, a feminist critique of social capital, and the role of social capital in adult learning.

  18. Classification of networks of automata by dynamical mean field theory

    International Nuclear Information System (INIS)

    Burda, Z.; Jurkiewicz, J.; Flyvbjerg, H.

    1990-01-01

    Dynamical mean field theory is used to classify the 2 24 =65,536 different networks of binary automata on a square lattice with nearest neighbour interactions. Application of mean field theory gives 700 different mean field classes, which fall in seven classes of different asymptotic dynamics characterized by fixed points and two-cycles. (orig.)

  19. Local-regional networks of persons with abilities in radioprotection and other actors in radioprotection. Audit report; Les reseaux loco-regionaux de personnes competentes en radioprotection et autres acteurs de la radioprotection. Rapport d'audit

    Energy Technology Data Exchange (ETDEWEB)

    Lefaure, Ch.

    2009-03-15

    As the regulation requires the existence of persons with abilities in radioprotection (PCR, personnes competentes en radioprotection) in many industrial, medical or research activities where ionizing radiations are present, in order to improve worker protection, these professionals who are much less acknowledged in these sectors than in the nuclear sector, felt the need to gather in regional and sector-based networks. This report proposes a presentation of three existing networks (the APCRAP, the Grand-Ouest network, and the Aquitaine-Sud-Ouest network). For each of them, the report addresses the following aspects: creation, objectives, statutes, members, activities, human, technical and financial resources, role. Then answers to a survey and to interviews are analyzed with respect to the professional sector and to the region, in terms of expectations towards the networks, and in terms of network operation and services. Interviews of institutional actors and union and management representatives are also analysed

  20. Spatial analysis of bus transport networks using network theory

    Science.gov (United States)

    Shanmukhappa, Tanuja; Ho, Ivan Wang-Hei; Tse, Chi Kong

    2018-07-01

    In this paper, we analyze the bus transport network (BTN) structure considering the spatial embedding of the network for three cities, namely, Hong Kong (HK), London (LD), and Bengaluru (BL). We propose a novel approach called supernode graph structuring for modeling the bus transport network. A static demand estimation procedure is proposed to assign the node weights by considering the points of interests (POIs) and the population distribution in the city over various localized zones. In addition, the end-to-end delay is proposed as a parameter to measure the topological efficiency of the bus networks instead of the shortest distance measure used in previous works. With the aid of supernode graph representation, important network parameters are analyzed for the directed, weighted and geo-referenced bus transport networks. It is observed that the supernode concept has significant advantage in analyzing the inherent topological behavior. For instance, the scale-free and small-world behavior becomes evident with supernode representation as compared to conventional or regular graph representation for the Hong Kong network. Significant improvement in clustering, reduction in path length, and increase in centrality values are observed in all the three networks with supernode representation. The correlation between topologically central nodes and the geographically central nodes reveals the interesting fact that the proposed static demand estimation method for assigning node weights aids in better identifying the geographically significant nodes in the network. The impact of these geographically significant nodes on the local traffic behavior is demonstrated by simulation using the SUMO (Simulation of Urban Mobility) tool which is also supported by real-world empirical data, and our results indicate that the traffic speed around a particular bus stop can reach a jammed state from a free flow state due to the presence of these geographically important nodes. A comparison

  1. Estimating network effect in geocenter motion: Theory

    Science.gov (United States)

    Zannat, Umma Jamila; Tregoning, Paul

    2017-10-01

    Geophysical models and their interpretations of several processes of interest, such as sea level rise, postseismic relaxation, and glacial isostatic adjustment, are intertwined with the need to realize the International Terrestrial Reference Frame. However, this realization needs to take into account the geocenter motion, that is, the motion of the center of figure of the Earth surface, due to, for example, deformation of the surface by earthquakes or hydrological loading effects. Usually, there is also a discrepancy, known as the network effect, between the theoretically convenient center of figure and the physically accessible center of network frames, because of unavoidable factors such as uneven station distribution, lack of stations in the oceans, disparity in the coverage between the two hemispheres, and the existence of tectonically deforming zones. Here we develop a method to estimate the magnitude of the network effect, that is, the error introduced by the incomplete sampling of the Earth surface, in measuring the geocenter motion, for a network of space geodetic stations of a fixed size N. For this purpose, we use, as our proposed estimate, the standard deviations of the changes in Helmert parameters measured by a random network of the same size N. We show that our estimate scales as 1/√N and give an explicit formula for it in terms of the vector spherical harmonics expansion of the displacement field. In a complementary paper we apply this formalism to coseismic displacements and elastic deformations due to surface water movements.

  2. Actor/Character Dualism

    DEFF Research Database (Denmark)

    Riis, Johannes

    2012-01-01

    Our perception of agency may be inherently fallible, and this may explain not only our general awareness of actors when engaged in fictional characters but also the specific case of paradoxical characters...

  3. Quantum Networks: General theory and applications

    International Nuclear Information System (INIS)

    Bisio, A.; D'Ariano, G. M.; Perinotti, P.; Chiribella, G.

    2011-01-01

    In this work we present a general mathematical framework to deal with Quantum Networks, i.e. networks resulting from the interconnection of elementary quantum circuits. The cornerstone of our approach is a generalization of the Choi isomorphism that allows one to efficiently represent any given Quantum Network in terms of a single positive operator. Our formalism allows one to face and solve many quantum information processing problems that would be hardly manageable otherwise, the most relevant of which are reviewed in this work: quantum process tomography, quantum cloning and learning of transformations, inversion of a unitary gate, information-disturbance tradeoff in estimating a unitary transformation, cloning and learning of a measurement device (Authors)

  4. Optimal transportation networks models and theory

    CERN Document Server

    Bernot, Marc; Morel, Jean-Michel

    2009-01-01

    The transportation problem can be formalized as the problem of finding the optimal way to transport a given measure into another with the same mass. In contrast to the Monge-Kantorovitch problem, recent approaches model the branched structure of such supply networks as minima of an energy functional whose essential feature is to favour wide roads. Such a branched structure is observable in ground transportation networks, in draining and irrigation systems, in electrical power supply systems and in natural counterparts such as blood vessels or the branches of trees. These lectures provide mathematical proof of several existence, structure and regularity properties empirically observed in transportation networks. The link with previous discrete physical models of irrigation and erosion models in geomorphology and with discrete telecommunication and transportation models is discussed. It will be mathematically proven that the majority fit in the simple model sketched in this volume.

  5. Building next-generation converged networks theory and practice

    CERN Document Server

    Pathan, Al-Sakib Khan

    2013-01-01

    Supplying a comprehensive introduction to next-generation networks, Building Next-Generation Converged Networks: Theory and Practice strikes a balance between how and why things work and how to make them work. It compiles recent advancements along with basic issues from the wide range of fields related to next generation networks. Containing the contributions of 56 industry experts and researchers from 16 different countries, the book presents relevant theoretical frameworks and the latest research. It investigates new technologies such as IPv6 over Low Power Wireless Personal Area Network (6L

  6. Pathways, Networks, and Systems: Theory and Experiments

    Energy Technology Data Exchange (ETDEWEB)

    Joseph H. Nadeau; John D. Lambris

    2004-10-30

    The international conference provided a unique opportunity for theoreticians and experimenters to exchange ideas, strategies, problems, challenges, language and opportunities in both formal and informal settings. This dialog is an important step towards developing a deep and effective integration of theory and experiments in studies of systems biology in humans and model organisms.

  7. Biological impacts and context of network theory

    Energy Technology Data Exchange (ETDEWEB)

    Almaas, E

    2007-01-05

    Many complex systems can be represented and analyzed as networks, and examples that have benefited from this approach span the natural sciences. For instance, we now know that systems as disparate as the World-Wide Web, the Internet, scientific collaborations, food webs, protein interactions and metabolism all have common features in their organization, the most salient of which are their scale-free connectivity distributions and their small-world behavior. The recent availability of large scale datasets that span the proteome or metabolome of an organism have made it possible to elucidate some of the organizational principles and rules that govern their function, robustness and evolution. We expect that combining the currently separate layers of information from gene regulatory-, signal transduction-, protein interaction- and metabolic networks will dramatically enhance our understanding of cellular function and dynamics.

  8. Integrated Adversarial Network Theory (iANT)

    Science.gov (United States)

    2011-07-01

    elite networks and governance changes in the 1980s. American Journal of Sociology, 103(1): 1-37. DiMaggio, P. 1986. Structural analysis of...Interorganization contagion in corporate philanthropy . Administrative Science Quarterly, 36(1): 88-105. Gargiulo, M., & Benassi, M. 1999. The dark...1): 7 1-84. Useem, M. 1979. The social organization ofthe American business elite and participation of corporation directors in the governance of

  9. Simulating activation propagation in social networks using the graph theory

    Directory of Open Access Journals (Sweden)

    František Dařena

    2010-01-01

    Full Text Available The social-network formation and analysis is nowadays one of objects that are in a focus of intensive research. The objective of the paper is to suggest the perspective of representing social networks as graphs, with the application of the graph theory to problems connected with studying the network-like structures and to study spreading activation algorithm for reasons of analyzing these structures. The paper presents the process of modeling multidimensional networks by means of directed graphs with several characteristics. The paper also demonstrates using Spreading Activation algorithm as a good method for analyzing multidimensional network with the main focus on recommender systems. The experiments showed that the choice of parameters of the algorithm is crucial, that some kind of constraint should be included and that the algorithm is able to provide a stable environment for simulations with networks.

  10. Parallel Distributed Processing Theory in the Age of Deep Networks.

    Science.gov (United States)

    Bowers, Jeffrey S

    2017-12-01

    Parallel distributed processing (PDP) models in psychology are the precursors of deep networks used in computer science. However, only PDP models are associated with two core psychological claims, namely that all knowledge is coded in a distributed format and cognition is mediated by non-symbolic computations. These claims have long been debated in cognitive science, and recent work with deep networks speaks to this debate. Specifically, single-unit recordings show that deep networks learn units that respond selectively to meaningful categories, and researchers are finding that deep networks need to be supplemented with symbolic systems to perform some tasks. Given the close links between PDP and deep networks, it is surprising that research with deep networks is challenging PDP theory. Copyright © 2017. Published by Elsevier Ltd.

  11. Information theory and the ethylene genetic network.

    Science.gov (United States)

    González-García, José S; Díaz, José

    2011-10-01

    The original aim of the Information Theory (IT) was to solve a purely technical problem: to increase the performance of communication systems, which are constantly affected by interferences that diminish the quality of the transmitted information. That is, the theory deals only with the problem of transmitting with the maximal precision the symbols constituting a message. In Shannon's theory messages are characterized only by their probabilities, regardless of their value or meaning. As for its present day status, it is generally acknowledged that Information Theory has solid mathematical foundations and has fruitful strong links with Physics in both theoretical and experimental areas. However, many applications of Information Theory to Biology are limited to using it as a technical tool to analyze biopolymers, such as DNA, RNA or protein sequences. The main point of discussion about the applicability of IT to explain the information flow in biological systems is that in a classic communication channel, the symbols that conform the coded message are transmitted one by one in an independent form through a noisy communication channel, and noise can alter each of the symbols, distorting the message; in contrast, in a genetic communication channel the coded messages are not transmitted in the form of symbols but signaling cascades transmit them. Consequently, the information flow from the emitter to the effector is due to a series of coupled physicochemical processes that must ensure the accurate transmission of the message. In this review we discussed a novel proposal to overcome this difficulty, which consists of the modeling of gene expression with a stochastic approach that allows Shannon entropy (H) to be directly used to measure the amount of uncertainty that the genetic machinery has in relation to the correct decoding of a message transmitted into the nucleus by a signaling pathway. From the value of H we can define a function I that measures the amount of

  12. Um modelo de atores e recursos para redes de cooperação entre empresas em obras de edificações A model of actors and resources for cooperation networks among companies in building projects

    Directory of Open Access Journals (Sweden)

    Fábio Müller Guerrini

    2011-03-01

    Full Text Available As redes de cooperação entre empresas têm papel estratégico para que as empresas acessem tecnologias, informação, mercados e recursos, aumentando assim seus conhecimentos, suas experiências e obtendo economias de escala e escopo. O objetivo do artigo é propor um modelo de atores e recursos para auxiliar a formação de redes de cooperação entre empresas de construção civil em obras de edificações. Para tal finalidade, realizou-se um estudo de caso múltiplo de caráter exploratório em sete obras de edificações em diferentes estágios de execução. A modelagem organizacional foi realizada com a metodologia Enterprise Knowledge Development (EKD para representar os relacionamentos interorganizacionais, as responsabilidades de cada ator envolvido e o processo de ciclo de vida da rede. Como resultado, sistematizou-se um modelo de atores e recursos para obras de edificações de modo que os potenciais gestores da rede tenham uma visão clara dos relacionamentos e responsabilidades dos atores na realização dos processos.The cooperation networks among companies have a strategic position to enable access to technologies, information, markets and resources, in order to increase knowledge, experiences and to get scale and scope economy. Using the theoretical referential on cooperation networks, this paper addresses a multiple exploratory case study in different execution stages, in order to provide potential network managers the comprehension about the relationship and responsibilities among actors in the execution process. The organizational modeling uses the Enterprise Knowledge Development (EKD methodology, to represent the relationship between actors and resources and the network life cycle. The results present a model of actors and resources for cooperation networks among companies in building projects.

  13. Workshop on Thermal Field Theory to Neural Networks

    CERN Document Server

    Veneziano, Gabriele; Aurenche, Patrick

    1996-01-01

    Tanguy Altherr was a Fellow in the Theory Division at CERN, on leave from LAPP (CNRS) Annecy. At the time of his accidental death in July 1994, he was only 31.A meeting was organized at CERN, covering the various aspects of his scientific interests: thermal field theory and its applications to hot or dense media, neural networks and its applications to high energy data analysis. Speakers were among his closest collaborators and friends.

  14. A network analysis of leadership theory : the infancy of integration.

    OpenAIRE

    Meuser, J. D.; Gardner, W. L.; Dinh, J. E.; Hu, J.; Liden, R. C.; Lord, R. G.

    2016-01-01

    We investigated the status of leadership theory integration by reviewing 14 years of published research (2000 through 2013) in 10 top journals (864 articles). The authors of these articles examined 49 leadership approaches/theories, and in 293 articles, 3 or more of these leadership approaches were included in their investigations. Focusing on these articles that reflected relatively extensive integration, we applied an inductive approach and used graphic network analysis as a guide for drawi...

  15. Social Network Theory in Engineering Education

    Science.gov (United States)

    Simon, Peter A.

    Collaborative groups are important both in the learning environment of engineering education and, in the real world, the business of engineering design. Selecting appropriate individuals to form an effective group and monitoring a group's progress are important aspects of successful task performance. This exploratory study looked at using the concepts of cognitive social structures, structural balance, and centrality from social network analysis as well as the measures of emotional intelligence. The concepts were used to analyze potential team members to examine if an individual's ability to perceive emotion in others and the self and to use, understand, and manage those emotions are a factor in a group's performance. The students from a capstone design course in computer engineering were used as volunteer subjects. They were formed into groups and assigned a design exercise to determine whether and which of the above-mentioned tools would be effective in both selecting teams and predicting the quality of the resultant design. The results were inconclusive with the exception of an individual's ability to accurately perceive emotions. The instruments that were successful were the Self-Monitoring scale and the accuracy scores derived from cognitive social structures and Level IV of network levels of analysis.

  16. Bridging disparate symptoms of schizophrenia: a triple network dysfunction theory

    Czech Academy of Sciences Publication Activity Database

    Nekovářová, Tereza; Fajnerová, Iveta; Horáček, J.; Španiel, F.

    2014-01-01

    Roč. 8, May 30 (2014), s. 171 ISSN 1662-5153 R&D Projects: GA MZd(CZ) NT13386; GA ČR(CZ) GAP303/12/1464; GA ČR(CZ) GBP304/12/G069; GA ČR(CZ) GA14-03627S Grant - others:GA MZd(CZ) NT14291; GA MZd(CZ) NT13843 Institutional support: RVO:67985823 Keywords : schizophrenia * self * theory of mind * forward model * default mode network * salience network * central executive network Subject RIV: FH - Neurology Impact factor: 3.270, year: 2014

  17. The structure of complex networks theory and applications

    CERN Document Server

    Estrada, Ernesto

    2012-01-01

    This book deals with the analysis of the structure of complex networks by combining results from graph theory, physics, and pattern recognition. The book is divided into two parts. 11 chapters are dedicated to the development of theoretical tools for the structural analysis of networks, and 7 chapters are illustrating, in a critical way, applications of these tools to real-world scenarios. The first chapters provide detailed coverage of adjacency and metric and topologicalproperties of networks, followed by chapters devoted to the analysis of individual fragments and fragment-based global inva

  18. Special Issue on ActorNetwork Theory, Value CoCreation and Design in Open Innovation Environments

    DEFF Research Database (Denmark)

    Tanev, Stoyan; Storni, Cristiano; Stuedahl, Dagny

    2015-01-01

    The present special issue focuses on the application of ANT to the articulation of a cocreative perspective on design in open innovation environments. The Editors invited submissions by authors using ANT to explore and discuss the link between value co-creation, design and innovation and especially...

  19. The Traffic Light Cosmos: Quasi-ethnographic approach to sustainable urban relational from the Actor-Network Theory

    Directory of Open Access Journals (Sweden)

    Carlos Silva

    2012-03-01

    Full Text Available Abstracts are the same as lists: One notices right away when something is missing. I warn the reader that the text I present here wants to capture the overall sense, but she knows that here and there gaps and simplifications are unavoidable and make this task difficult. The reader is aware of it not only because it is any abstract’s destiny, but because a map which is the same size as the territory represented does not go anywhere. It has to necessarily be something else than the territory. Thus, this abstract is something other than the thesis to which it refers. In this text that follows I will discuss the platform where I deployed the instances that shaped my research. Secondly, I will refer to two of the several counter-intuitions that populate my thesis in relation to my view on the issue of sustainability, namely, to patience and perseverance in the sustainable future I oppose the presentist impatience of the sustainable instant and, at the end of this section, I will briefly discuss relational urban sustainability, specifically, the normative framework or, if you will, the vindication of control as an instance for sustainability. Third, I will offer some conclusions of my work.

  20. Quantized detector networks the theory of observation

    CERN Document Server

    Jaroszkiewicz, George

    2017-01-01

    Scientists have been debating the meaning of quantum mechanics for over a century. This book for graduate students and researchers gets to the root of the problem; the contextual nature of empirical truth, the laws of observation and how these impact on our understanding of quantum physics. Bridging the gap between non-relativistic quantum mechanics and quantum field theory, this novel approach to quantum mechanics extends the standard formalism to cover the observer and their apparatus. The author demystifies some of the aspects of quantum mechanics that have traditionally been regarded as extraordinary, such as wave-particle duality and quantum superposition, by emphasizing the scientific principles rather than the mathematical modelling involved. Including key experiments and worked examples throughout to encourage the reader to focus on empirically sound concepts, this book avoids metaphysical speculation and also alerts the reader to the use of computer algebra to explore quantum experiments of virtually...

  1. Actors at work

    NARCIS (Netherlands)

    Nobakht, Behrooz

    2016-01-01

    The core contributions of this thesis target the intersection of object orientation, actor model, and concurrency. We choose Java as the main target programming language and as one of the mainstream object-oriented languages. We formalize a subset of Java and its concurrency API to facilitate formal

  2. Network theory and its applications in economic systems

    Science.gov (United States)

    Huang, Xuqing

    This dissertation covers the two major parts of my Ph.D. research: i) developing theoretical framework of complex networks; and ii) applying complex networks models to quantitatively analyze economics systems. In part I, we focus on developing theories of interdependent networks, which includes two chapters: 1) We develop a mathematical framework to study the percolation of interdependent networks under targeted-attack and find that when the highly connected nodes are protected and have lower probability to fail, in contrast to single scale-free (SF) networks where the percolation threshold pc = 0, coupled SF networks are significantly more vulnerable with pc significantly larger than zero. 2) We analytically demonstrates that clustering, which quantifies the propensity for two neighbors of the same vertex to also be neighbors of each other, significantly increases the vulnerability of the system. In part II, we apply the complex networks models to study economics systems, which also includes two chapters: 1) We study the US corporate governance network, in which nodes representing directors and links between two directors representing their service on common company boards, and propose a quantitative measure of information and influence transformation in the network. Thus we are able to identify the most influential directors in the network. 2) We propose a bipartite networks model to simulate the risk propagation process among commercial banks during financial crisis. With empirical bank's balance sheet data in 2007 as input to the model, we find that our model efficiently identifies a significant portion of the actual failed banks reported by Federal Deposit Insurance Corporation during the financial crisis between 2008 and 2011. The results suggest that complex networks model could be useful for systemic risk stress testing for financial systems. The model also identifies that commercial rather than residential real estate assets are major culprits for the

  3. The Network Theory of Well-Being: An Introduction

    Directory of Open Access Journals (Sweden)

    Michael Bishop

    2012-11-01

    Full Text Available In this paper, I propose a novel approach to investigating the nature of well-being and a new theory about well-being. The approach is integrative and naturalistic. It holds that a theory of well-being should account for two different classes of evidence – our commonsense judgments about well-being and the science of well-being (i.e., positive psychology. The network theory holds that a person is in the state of well-being if she instantiates a homeostatically clustered network of feelings, emotions, attitudes, behaviors, traits, and interactions with the world that tends to have a relatively high number of states that feel good, that lead to states that feel good, or that are valued by the agent or her culture.

  4. Towards a predictive theory for genetic regulatory networks

    Science.gov (United States)

    Tkacik, Gasper

    When cells respond to changes in the environment by regulating the expression levels of their genes, we often draw parallels between these biological processes and engineered information processing systems. One can go beyond this qualitative analogy, however, by analyzing information transmission in biochemical ``hardware'' using Shannon's information theory. Here, gene regulation is viewed as a transmission channel operating under restrictive constraints set by the resource costs and intracellular noise. We present a series of results demonstrating that a theory of information transmission in genetic regulatory circuits feasibly yields non-trivial, testable predictions. These predictions concern strategies by which individual gene regulatory elements, e.g., promoters or enhancers, read out their signals; as well as strategies by which small networks of genes, independently or in spatially coupled settings, respond to their inputs. These predictions can be quantitatively compared to the known regulatory networks and their function, and can elucidate how reproducible biological processes, such as embryonic development, can be orchestrated by networks built out of noisy components. Preliminary successes in the gap gene network of the fruit fly Drosophila indicate that a full ab initio theoretical prediction of a regulatory network is possible, a feat that has not yet been achieved for any real regulatory network. We end by describing open challenges on the path towards such a prediction.

  5. Analyzing complex networks evolution through Information Theory quantifiers

    International Nuclear Information System (INIS)

    Carpi, Laura C.; Rosso, Osvaldo A.; Saco, Patricia M.; Ravetti, Martin Gomez

    2011-01-01

    A methodology to analyze dynamical changes in complex networks based on Information Theory quantifiers is proposed. The square root of the Jensen-Shannon divergence, a measure of dissimilarity between two probability distributions, and the MPR Statistical Complexity are used to quantify states in the network evolution process. Three cases are analyzed, the Watts-Strogatz model, a gene network during the progression of Alzheimer's disease and a climate network for the Tropical Pacific region to study the El Nino/Southern Oscillation (ENSO) dynamic. We find that the proposed quantifiers are able not only to capture changes in the dynamics of the processes but also to quantify and compare states in their evolution.

  6. Analyzing complex networks evolution through Information Theory quantifiers

    Energy Technology Data Exchange (ETDEWEB)

    Carpi, Laura C., E-mail: Laura.Carpi@studentmail.newcastle.edu.a [Civil, Surveying and Environmental Engineering, University of Newcastle, University Drive, Callaghan NSW 2308 (Australia); Departamento de Fisica, Instituto de Ciencias Exatas, Universidade Federal de Minas Gerais, Av. Antonio Carlos 6627, Belo Horizonte (31270-901), MG (Brazil); Rosso, Osvaldo A., E-mail: rosso@fisica.ufmg.b [Departamento de Fisica, Instituto de Ciencias Exatas, Universidade Federal de Minas Gerais, Av. Antonio Carlos 6627, Belo Horizonte (31270-901), MG (Brazil); Chaos and Biology Group, Instituto de Calculo, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Pabellon II, Ciudad Universitaria, 1428 Ciudad de Buenos Aires (Argentina); Saco, Patricia M., E-mail: Patricia.Saco@newcastle.edu.a [Civil, Surveying and Environmental Engineering, University of Newcastle, University Drive, Callaghan NSW 2308 (Australia); Departamento de Hidraulica, Facultad de Ciencias Exactas, Ingenieria y Agrimensura, Universidad Nacional de Rosario, Avenida Pellegrini 250, Rosario (Argentina); Ravetti, Martin Gomez, E-mail: martin.ravetti@dep.ufmg.b [Departamento de Engenharia de Producao, Universidade Federal de Minas Gerais, Av. Antonio Carlos, 6627, Belo Horizonte (31270-901), MG (Brazil)

    2011-01-24

    A methodology to analyze dynamical changes in complex networks based on Information Theory quantifiers is proposed. The square root of the Jensen-Shannon divergence, a measure of dissimilarity between two probability distributions, and the MPR Statistical Complexity are used to quantify states in the network evolution process. Three cases are analyzed, the Watts-Strogatz model, a gene network during the progression of Alzheimer's disease and a climate network for the Tropical Pacific region to study the El Nino/Southern Oscillation (ENSO) dynamic. We find that the proposed quantifiers are able not only to capture changes in the dynamics of the processes but also to quantify and compare states in their evolution.

  7. Water supply network district metering theory and case study

    CERN Document Server

    Di Nardo, Armando; Di Mauro, Anna

    2013-01-01

    The management of a water supply network can be substantially improved defining permanent sectors or districts that enhances simpler water loss detection and pressure management. However, the water network partitioning may compromise water system performance, since some pipes are usually closed to delimit districts in order not to have too many metering stations, to decrease costs and simplify water balance. This may reduce the reliability of the whole system and not guarantee the delivery of water at the different network nodes. In practical applications, the design of districts or sectors is generally based on empirical approaches or on limited field experiences. The book proposes a design support methodology, based on graph theory principles and tested on real case study. The described methodology can help water utilities, professionals and researchers to define the optimal districts or sectors of a water supply network.

  8. New Actors and Alliances in Development

    DEFF Research Database (Denmark)

    Richey, Lisa Ann; Ponte, Stefano

    2014-01-01

    ‘New actors and alliances in development’ brings together an interdisciplinary group of scholars exploring how development financing and interventions are being shaped by a wider and more complex platform of actors than usually considered in the existing literature. The contributors also trace...... a changing set of key relations and alliances in development – those between business and consumers; ngos and celebrities; philanthropic organisations and the state; diaspora groups and transnational advocacy networks; ruling elites and productive capitalists; and ‘new donors’ and developing country...

  9. Dynamical graph theory networks techniques for the analysis of sparse connectivity networks in dementia

    Science.gov (United States)

    Tahmassebi, Amirhessam; Pinker-Domenig, Katja; Wengert, Georg; Lobbes, Marc; Stadlbauer, Andreas; Romero, Francisco J.; Morales, Diego P.; Castillo, Encarnacion; Garcia, Antonio; Botella, Guillermo; Meyer-Bäse, Anke

    2017-05-01

    Graph network models in dementia have become an important computational technique in neuroscience to study fundamental organizational principles of brain structure and function of neurodegenerative diseases such as dementia. The graph connectivity is reflected in the connectome, the complete set of structural and functional connections of the graph network, which is mostly based on simple Pearson correlation links. In contrast to simple Pearson correlation networks, the partial correlations (PC) only identify direct correlations while indirect associations are eliminated. In addition to this, the state-of-the-art techniques in brain research are based on static graph theory, which is unable to capture the dynamic behavior of the brain connectivity, as it alters with disease evolution. We propose a new research avenue in neuroimaging connectomics based on combining dynamic graph network theory and modeling strategies at different time scales. We present the theoretical framework for area aggregation and time-scale modeling in brain networks as they pertain to disease evolution in dementia. This novel paradigm is extremely powerful, since we can derive both static parameters pertaining to node and area parameters, as well as dynamic parameters, such as system's eigenvalues. By implementing and analyzing dynamically both disease driven PC-networks and regular concentration networks, we reveal differences in the structure of these network that play an important role in the temporal evolution of this disease. The described research is key to advance biomedical research on novel disease prediction trajectories and dementia therapies.

  10. Ordering, materiality, and multiplicity: Enacting Actor–Network Theory in tourism

    NARCIS (Netherlands)

    Duim, van der R.; Ren, C.; Johannesson, G.T.

    2013-01-01

    In this article, we demonstrate how Actor–Network Theory has been translated into tourism research. The article presents and discusses three concepts integral to the Actor–Network Theory approach: ordering, materiality, and multiplicity. We first briefly introduce Actor–Network Theory and draw

  11. Review of network research in scientific journal ‘Entrepreneurship Theory and Practice’

    OpenAIRE

    Agnieszka Brzozowska; Michał Zdziarski

    2016-01-01

    This article aims at presenting a systematic review of publications that verified the network theory and the theory of networks empirically, published in the entrepreneurship journal with the highest Impact Factor: “Entrepreneurship Theory and Practice”. We present how publication frequency evolved over time, and classify papers into major streams of entrepreneurship research. Our findings suggest the theory of networks is an under-researched area promising for further advancing the theory of...

  12. Animal Social Network Theory Can Help Wildlife Conservation.

    Science.gov (United States)

    Snijders, Lysanne; Blumstein, Daniel T; Stanley, Christina R; Franks, Daniel W

    2017-08-01

    Many animals preferentially associate with certain other individuals. This social structuring can influence how populations respond to changes to their environment, thus making network analysis a promising technique for understanding, predicting, and potentially manipulating population dynamics. Various network statistics can correlate with individual fitness components and key population-level processes, yet the logical role and formal application of animal social network theory for conservation and management have not been well articulated. We outline how understanding of direct and indirect relationships between animals can be profitably applied by wildlife managers and conservationists. By doing so, we aim to stimulate the development and implementation of practical tools for wildlife conservation and management and to inspire novel behavioral research in this field. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Transient response of nonlinear polymer networks: A kinetic theory

    Science.gov (United States)

    Vernerey, Franck J.

    2018-06-01

    Dynamic networks are found in a majority of natural materials, but also in engineering materials, such as entangled polymers and physically cross-linked gels. Owing to their transient bond dynamics, these networks display a rich class of behaviors, from elasticity, rheology, self-healing, or growth. Although classical theories in rheology and mechanics have enabled us to characterize these materials, there is still a gap in our understanding on how individuals (i.e., the mechanics of each building blocks and its connection with others) affect the emerging response of the network. In this work, we introduce an alternative way to think about these networks from a statistical point of view. More specifically, a network is seen as a collection of individual polymer chains connected by weak bonds that can associate and dissociate over time. From the knowledge of these individual chains (elasticity, transient attachment, and detachment events), we construct a statistical description of the population and derive an evolution equation of their distribution based on applied deformation and their local interactions. We specifically concentrate on nonlinear elastic response that follows from the strain stiffening response of individual chains of finite size. Upon appropriate averaging operations and using a mean field approximation, we show that the distribution can be replaced by a so-called chain distribution tensor that is used to determine important macroscopic measures such as stress, energy storage and dissipation in the network. Prediction of the kinetic theory are then explored against known experimental measurement of polymer responses under uniaxial loading. It is found that even under the simplest assumptions of force-independent chain kinetics, the model is able to reproduce complex time-dependent behaviors of rubber and self-healing supramolecular polymers.

  14. Game Theory for Wireless Sensor Networks: A Survey

    Science.gov (United States)

    Shi, Hai-Yan; Wang, Wan-Liang; Kwok, Ngai-Ming; Chen, Sheng-Yong

    2012-01-01

    Game theory (GT) is a mathematical method that describes the phenomenon of conflict and cooperation between intelligent rational decision-makers. In particular, the theory has been proven very useful in the design of wireless sensor networks (WSNs). This article surveys the recent developments and findings of GT, its applications in WSNs, and provides the community a general view of this vibrant research area. We first introduce the typical formulation of GT in the WSN application domain. The roles of GT are described that include routing protocol design, topology control, power control and energy saving, packet forwarding, data collection, spectrum allocation, bandwidth allocation, quality of service control, coverage optimization, WSN security, and other sensor management tasks. Then, three variations of game theory are described, namely, the cooperative, non-cooperative, and repeated schemes. Finally, existing problems and future trends are identified for researchers and engineers in the field. PMID:23012533

  15. Game Theory for Wireless Sensor Networks: A Survey

    Directory of Open Access Journals (Sweden)

    Ngai-Ming Kwok

    2012-07-01

    Full Text Available Game theory (GT is a mathematical method that describes the phenomenon of conflict and cooperation between intelligent rational decision-makers. In particular, the theory has been proven very useful in the design of wireless sensor networks (WSNs. This article surveys the recent developments and findings of GT, its applications in WSNs, and provides the community a general view of this vibrant research area. We first introduce the typical formulation of GT in the WSN application domain. The roles of GT are described that include routing protocol design, topology control, power control and energy saving, packet forwarding, data collection, spectrum allocation, bandwidth allocation, quality of service control, coverage optimization, WSN security, and other sensor management tasks. Then, three variations of game theory are described, namely, the cooperative, non-cooperative, and repeated schemes. Finally, existing problems and future trends are identified for researchers and engineers in the field.

  16. Composing Networks: Writing Practices on Mobile Devices

    Science.gov (United States)

    Swarts, Jason

    2016-01-01

    This article is an investigation of composing practices through which people create networks with mobile phones. By looking through the lens of actor-network theory, the author portrays the networking activity of mobile phone users as translation, what Latour describes as an infralanguage to which different disciplinary perspectives can be…

  17. Complex Network Theory Applied to the Growth of Kuala Lumpur's Public Urban Rail Transit Network.

    Directory of Open Access Journals (Sweden)

    Rui Ding

    Full Text Available Recently, the number of studies involving complex network applications in transportation has increased steadily as scholars from various fields analyze traffic networks. Nonetheless, research on rail network growth is relatively rare. This research examines the evolution of the Public Urban Rail Transit Networks of Kuala Lumpur (PURTNoKL based on complex network theory and covers both the topological structure of the rail system and future trends in network growth. In addition, network performance when facing different attack strategies is also assessed. Three topological network characteristics are considered: connections, clustering and centrality. In PURTNoKL, we found that the total number of nodes and edges exhibit a linear relationship and that the average degree stays within the interval [2.0488, 2.6774] with heavy-tailed distributions. The evolutionary process shows that the cumulative probability distribution (CPD of degree and the average shortest path length show good fit with exponential distribution and normal distribution, respectively. Moreover, PURTNoKL exhibits clear cluster characteristics; most of the nodes have a 2-core value, and the CPDs of the centrality's closeness and betweenness follow a normal distribution function and an exponential distribution, respectively. Finally, we discuss four different types of network growth styles and the line extension process, which reveal that the rail network's growth is likely based on the nodes with the biggest lengths of the shortest path and that network protection should emphasize those nodes with the largest degrees and the highest betweenness values. This research may enhance the networkability of the rail system and better shape the future growth of public rail networks.

  18. Complex Network Theory Applied to the Growth of Kuala Lumpur's Public Urban Rail Transit Network.

    Science.gov (United States)

    Ding, Rui; Ujang, Norsidah; Hamid, Hussain Bin; Wu, Jianjun

    2015-01-01

    Recently, the number of studies involving complex network applications in transportation has increased steadily as scholars from various fields analyze traffic networks. Nonetheless, research on rail network growth is relatively rare. This research examines the evolution of the Public Urban Rail Transit Networks of Kuala Lumpur (PURTNoKL) based on complex network theory and covers both the topological structure of the rail system and future trends in network growth. In addition, network performance when facing different attack strategies is also assessed. Three topological network characteristics are considered: connections, clustering and centrality. In PURTNoKL, we found that the total number of nodes and edges exhibit a linear relationship and that the average degree stays within the interval [2.0488, 2.6774] with heavy-tailed distributions. The evolutionary process shows that the cumulative probability distribution (CPD) of degree and the average shortest path length show good fit with exponential distribution and normal distribution, respectively. Moreover, PURTNoKL exhibits clear cluster characteristics; most of the nodes have a 2-core value, and the CPDs of the centrality's closeness and betweenness follow a normal distribution function and an exponential distribution, respectively. Finally, we discuss four different types of network growth styles and the line extension process, which reveal that the rail network's growth is likely based on the nodes with the biggest lengths of the shortest path and that network protection should emphasize those nodes with the largest degrees and the highest betweenness values. This research may enhance the networkability of the rail system and better shape the future growth of public rail networks.

  19. Digital Citizen Participation within Schools in the United Kingdom and Indonesia: An Actor–Network Theory (ANT Perspective

    Directory of Open Access Journals (Sweden)

    Muhammad Yusuf

    2016-11-01

    Full Text Available Citizen engagement and participation are a key focus for government and government agencies, and with the advent of Internet technologies questions arise about the role and impact of technology on citizen participation. This paper aims to explore the role of technology in citizen participation within schools. This research used in-depth comparative case studies using examples from two different schools and school systems, one in the United Kingdom and one in Indonesia. The wider school systems are complex and dynamic environments with multiple stakeholders, media, and supporting systems, and the schools operate under geopolitical and social influences. This paper provides a framework, based on Actor-Network Theory (ANT, for capturing e-participation in schools, particularly identifying the influence of technology as a conduit for enabling, engaging, and empowering stakeholders.

  20. Network Theory and Effects of Transcranial Brain Stimulation Methods on the Brain Networks

    Directory of Open Access Journals (Sweden)

    Sema Demirci

    2014-12-01

    Full Text Available In recent years, there has been a shift from classic localizational approaches to new approaches where the brain is considered as a complex system. Therefore, there has been an increase in the number of studies involving collaborations with other areas of neurology in order to develop methods to understand the complex systems. One of the new approaches is graphic theory that has principles based on mathematics and physics. According to this theory, the functional-anatomical connections of the brain are defined as a network. Moreover, transcranial brain stimulation techniques are amongst the recent research and treatment methods that have been commonly used in recent years. Changes that occur as a result of applying brain stimulation techniques on physiological and pathological networks help better understand the normal and abnormal functions of the brain, especially when combined with techniques such as neuroimaging and electroencephalography. This review aims to provide an overview of the applications of graphic theory and related parameters, studies conducted on brain functions in neurology and neuroscience, and applications of brain stimulation systems in the changing treatment of brain network models and treatment of pathological networks defined on the basis of this theory.

  1. Theory and design of broadband matching networks applied electricity and electronics

    CERN Document Server

    Chen, Wai-Kai

    1976-01-01

    Theory and Design of Broadband Matching Networks centers on the network theory and its applications to the design of broadband matching networks and amplifiers. Organized into five chapters, this book begins with a description of the foundation of network theory. Chapter 2 gives a fairly complete exposition of the scattering matrix associated with an n-port network. Chapter 3 considers the approximation problem along with a discussion of the approximating functions. Chapter 4 explains the Youla's theory of broadband matching by illustrating every phase of the theory with fully worked out examp

  2. Theory of liquid crystal elastomers and polymer networks : Connection between neoclassical theory and differential geometry.

    Science.gov (United States)

    Nguyen, Thanh-Son; Selinger, Jonathan V

    2017-09-01

    In liquid crystal elastomers and polymer networks, the orientational order of liquid crystals is coupled with elastic distortions of crosslinked polymers. Previous theoretical research has described these materials through two different approaches: a neoclassical theory based on the liquid crystal director and the deformation gradient tensor, and a geometric elasticity theory based on the difference between the actual metric tensor and a reference metric. Here, we connect those two approaches using a formalism based on differential geometry. Through this connection, we determine how both the director and the geometry respond to a change of temperature.

  3. Elegant Coercion and Iran: Beyond the Unitary Actor Model

    National Research Council Canada - National Science Library

    Moss, J. C

    2005-01-01

    .... At its core, then, coercion is about state decision-making. Most theories of coercion describe states as if they were unitary actors whose decision-making results from purely rational cost-benefit calculations...

  4. European Conference on Game Theory & Networking Games and Management

    CERN Document Server

    Mazalov, Vladimir

    2016-01-01

    This contributed volume contains fourteen papers based on selected presentations from the European Conference on Game Theory SING11-GTM 2015, held at Saint Petersburg State University in July 2015, and the Networking Games and Management workshop, held at the Karelian Research Centre of the Russian Academy of Sciences in Petrozvavodsk, Russia, also in July 2015. These papers cover a wide range of topics in game theory, including recent advances in areas with high potential for future work, as well as new developments on classical results. Some of these include A new approach to journal ranking using methods from social choice theory; A differential game of a duopoly in which two firms are competing for market share in an industry with network externalities; The impact of information propagation in the model of tax audits; A voting model in which the results of previous votes can affect the process of coalition formation in a decision-making body; The Selten-Szidarovsky technique for the analysis of Nash equil...

  5. Actors and Practices

    DEFF Research Database (Denmark)

    Balslev, Lars

    Actors and practices – An institutional study on management accounting change in Air Greenland My former CEO was one of the first executives in Greenland to formally implement an extensive commercial strategy to identify the contradictory forces of social obligations and commercial strivings...... societal obligation. He noted that: “…there is some inherent conflict in having the type of ownership we have, one in which the commercial owner demands higher profits or they will sell their shares, and the other two government owners, where one wishes to have the lowest possible fares and better...... infrastructure and the other one just wants less trouble. Well! This is the ongoing inherent conflict of the owner composition we just have to deal with.” He emphasized that SAS, the more “commercial oriented” owner and private shareholder, wanted higher profits and gains, whereas the Government of Greenland...

  6. Matching Theory for Channel Allocation in Cognitive Radio Networks

    Directory of Open Access Journals (Sweden)

    L. Cao

    2016-12-01

    Full Text Available For a cognitive radio network (CRN in which a set of secondary users (SUs competes for a limited number of channels (spectrum resources belonging to primary users (PUs, the channel allocation is a challenge and dominates the throughput and congestion of the network. In this paper, the channel allocation problem is first formulated as the 0-1 integer programming optimization, with considering the overall utility both of primary system and secondary system. Inspired by matching theory, a many-to-one matching game is used to remodel the channel allocation problem, and the corresponding PU proposing deferred acceptance (PPDA algorithm is also proposed to yield a stable matching. We compare the performance and computation complexity between these two solutions. Numerical results demonstrate the efficiency and obtain the communication overhead of the proposed scheme.

  7. Bridging disparate symptoms of schizophrenia: a Triple network dysfunction theory

    Directory of Open Access Journals (Sweden)

    Tereza eNekovarova

    2014-05-01

    Full Text Available Schizophrenia is a complex neuropsychiatric disorder with variable symptomatology, traditionally divided into positive and negative symptoms, and cognitive deficits. Yet, the etiology of this disorder has yet to be fully understood.Recent findings suggest that alteration of the basic sense of self-awareness may be an essential distortion of schizophrenia spectrum disorders. In addition, extensive research of social and mentalizing abilities has stressed the role of distortion of social skills in schizophrenia.This article aims to propose and support a concept of triple brain network model of the dysfunctional switching between default mode and central executive network related to the aberrant activity of salience network. This model could represent a unitary mechanism of a wide array of symptom domains present in schizophrenia including the deficit of SELF (self-awareness and self-representation and theory of mind (ToM dysfunctions along with the traditional positive, negative and cognitive domains. We review previous studies which document the dysfunctions of SELF and ToM in schizophrenia together with neuroimaging data elucidating the triple brain network model as a common neuronal substrate of this dysfunction.

  8. Pearson's correlation coefficient in the theory of networks: A comment

    OpenAIRE

    Ahmed, Zafar; Kumar, Sachin

    2018-01-01

    In statistics, the Pearson correlation coefficient $r_{x,y}$ determines the degree of linear correlation between two variables and it is known that $-1 \\le r_{x,y} \\le 1$. In the theory of networks, a curious expression proposed in [PRL {\\bf 89} 208701 (2002)] for degree-degree correlation coefficient $r_{j_i,k_i}, i\\in [1,M]$ has been in use. We realize that the suggested form is the conventional Pearson's coefficient for $\\{(j_i,k_i), (k_i,j_i)\\}$ for $2M$ data points and hence it is rightl...

  9. Disaggregated regulation in network sections: The normative and positive theory; Disaggregierte Regulierung in Netzsektoren: Normative und positive Theorie

    Energy Technology Data Exchange (ETDEWEB)

    Knieps, G. [Inst. fuer Verkehrswissenschaft und Regionalpolitik, Albert-Ludwigs-Univ. Freiburg i.B. (Germany)

    2007-09-15

    The article deals with the interaction of normative and positive theorie of regulation. Those parts of the network which need regulation could be localised and regulated with the help of the normative theory of the monopolistic bottlenecks. Using the positive theory, the basic elements of a mandate for regulation in the sense of the disaggregated economy of regulation are derived.

  10. Multispectral Image classification using the theories of neural networks

    International Nuclear Information System (INIS)

    Ardisasmita, M.S.; Subki, M.I.R.

    1997-01-01

    Image classification is the one of the important part of digital image analysis. the objective of image classification is to identify and regroup the features occurring in an image into one or several classes in terms of the object. basic to the understanding of multispectral classification is the concept of the spectral response of an object as a function of the electromagnetic radiation and the wavelength of the spectrum. new approaches to classification has been developed to improve the result of analysis, these state-of-the-art classifiers are based upon the theories of neural networks. Neural network classifiers are algorithmes which mimic the computational abilities of the human brain. Artificial neurons are simple emulation's of biological neurons; they take in information from sensors or other artificial neurons, perform very simple operations on this data, and pass the result to other recognize the spectral signature of each image pixel. Neural network image classification has been divided into supervised and unsupervised training procedures. In the supervised approach, examples of each cover type can be located and the computer can compute spectral signatures to categorize all pixels in a digital image into several land cover classes. In supervised classification, spectral signatures are generated by mathematically grouping and it does not require analyst-specified training data. Thus, in the supervised approach we define useful information categories and then examine their spectral reparability; in the unsupervised approach the computer determines spectrally sapable classes and then we define thei information value

  11. Toward a Theory of Industrial Supply Networks: A Multi-Level Perspective via Network Analysis

    Directory of Open Access Journals (Sweden)

    Yi Zuo

    2017-07-01

    Full Text Available In most supply chains (SCs, transaction relationships between suppliers and customers are commonly considered to be an extrapolation from a linear perspective. However, this traditional linear concept of an SC is egotistic and oversimplified and does not sufficiently reflect the complex and cyclical structure of supplier-customer relationships in current economic and industrial situations. The interactional relationships and topological characteristics between suppliers and customers should be analyzed using supply networks (SNs rather than traditional linear SCs. Therefore, this paper reconceptualizes SCs as SNs in complex adaptive systems (CAS, and presents three main contributions. First, we propose an integrated framework of CAS network by synthesizing multi-level network analysis from the network-, community- and vertex-perspective. The CAS perspective enables us to understand the advances of SN properties. Second, in order to emphasize the CAS properties of SNs, we conducted a real-world SN based on the Japanese industry and describe an advanced investigation of SN theory. The CAS properties help in enriching the SN theory, which can benefit SN management, community economics and industrial resilience. Third, we propose a quantitative metric of entropy to measure the complexity and robustness of SNs. The results not only support a specific understanding of the structural outcomes relevant to SNs, but also deliver efficient and effective support to the management and design of SNs.

  12. Theorizing "Lay Theories of Media": A Case Study of the Dissent! Network at the 2005 Gleneagles G8 Summit

    NARCIS (Netherlands)

    P. McCurdy (Patrick)

    2011-01-01

    textabstractDrawing on "active audience studies" and recent theories of mediation, the concept of "lay theories of media" is proposed as a means to understand how social movement actors think about and interact with news media as part of the "practice" of activism. The argument is made via a case

  13. International Political Actorness of the European Union: Evaluation Criteria

    Directory of Open Access Journals (Sweden)

    GNATYUK N.N.

    2014-06-01

    Full Text Available The European Union is a completely new international entity which is hard to evaluate using traditional criteria of political actorness. Its active international presence stimulates the modeling of international actor features beyond the scope of “state-international organization” scheme. The concept of international actorness serves as a starting point for the development of appropriate analytical model. Unlike the traditional state-centered approaches which define an international actor through its affiliation witch the international system, this concept operates at the internal level of international entity and at the international structure level. Furthermore, both of these levels are treated as ontologically neutral and mutually constitutive. This basic theoretical scheme is used for elaboration of evaluation criteria of political actorness. The proposed system of criteria is based on drawing, synthesizing and developing the main writings on “new international actors” since the times of classic work by Carol A. Cosgrove and Kenneth J. Twitchett. The key elements of actorness assessed in this article include defining of capacity to act on the global scene as well as the acceptance by other actors and by international system as a whole. At the internal level, the EU’s actor capacity is measured by assessing its core elements ranging from core aspects, such as autonomy, authority, actor capability, coherence and cohesion to identity aspects. On the external level, the decisive criteria are recognition and acceptance by others which reflect expectations and perceptions of the EU. The proposed approach of evaluating the international actorness enables us to consider the political activity of the EU on the basis of coordinated system of interaction between the variables of international and domestic levels of the analysis. Furthermore, this contributes to the development of cumulative, coherent, and comprehensive theory of international

  14. Bridging the Gap in Port Security; Network Centric Theory Applied to Public/Private Collaboration

    National Research Council Canada - National Science Library

    Wright, Candice L

    2007-01-01

    ...." Admiral Thad Allen, 2007 The application of Network Centric Warfare theory enables all port stakeholders to better prepare for a disaster through increased information sharing and collaboration...

  15. Differential theory of learning for efficient neural network pattern recognition

    Science.gov (United States)

    Hampshire, John B., II; Vijaya Kumar, Bhagavatula

    1993-09-01

    We describe a new theory of differential learning by which a broad family of pattern classifiers (including many well-known neural network paradigms) can learn stochastic concepts efficiently. We describe the relationship between a classifier's ability to generate well to unseen test examples and the efficiency of the strategy by which it learns. We list a series of proofs that differential learning is efficient in its information and computational resource requirements, whereas traditional probabilistic learning strategies are not. The proofs are illustrated by a simple example that lends itself to closed-form analysis. We conclude with an optical character recognition task for which three different types of differentially generated classifiers generalize significantly better than their probabilistically generated counterparts.

  16. New actors in environmental management: The case of the civil society in Ensenada

    Directory of Open Access Journals (Sweden)

    Nain Martínez

    2014-01-01

    Full Text Available The environment is a complex space where multiple interests converge, so the traditional government has been insufficient to respond to the new demands of the environmental management. In this sense, the theory governance suggests a bigger role for social actors in decision-making for a more effective resolution of environmental problems. This article focuses on the Civil Society Organizations (cso’s of Ensenada, due to its relevance in the public sphere and the ecological value of the area. Twenty two csos, its participants and the network of actors were characterized through a survey. It was found that three types of csos are focusing on the conservation agenda and urban sustainability.

  17. Application of Game Theory Approaches in Routing Protocols for Wireless Networks

    Science.gov (United States)

    Javidi, Mohammad M.; Aliahmadipour, Laya

    2011-09-01

    An important and essential issue for wireless networks is routing protocol design that is a major technical challenge due to the function of the network. Game theory is a powerful mathematical tool that analyzes the strategic interactions among multiple decision makers and the results of researches show that applied game theory in routing protocol lead to improvement the network performance through reduce overhead and motivates selfish nodes to collaborate in the network. This paper presents a review and comparison for typical representatives of routing protocols designed that applied game theory approaches for various wireless networks such as ad hoc networks, mobile ad hoc networks and sensor networks that all of them lead to improve the network performance.

  18. Bipartite Networks

    NARCIS (Netherlands)

    Agneessens, F.; Moser, C.; Barnett, G.A.

    2011-01-01

    Bipartite networks refer to a specific kind of network in which the nodes (or actors) can be partitioned into two subsets based on the fact that no links exist between actors within each subset, but only between the two subsets. Due to the partition of actors in two sets and the absence of relations

  19. Understanding Event-based Business Networks

    OpenAIRE

    2008-01-01

    Abstract This article deals with the temporality in business networks. Marketing as networks approach stresses interaction processes and interdependence among actors noting that business markets are mainly socially constructed. The approach has increased our understanding of business marketing but further attention for theory development and empirical validation is needed. Theoretical foundations of the approach are conceptually analysed here, taking time and timing into particular...

  20. Of International Actors, Nodal Governance and the African Peer ...

    African Journals Online (AJOL)

    Based on the recent political unrest in Kenya, I argue that one way in which the. African Peer Review Mechanism (APRM) can improve governance in Africa and indeed see through the implementation of its review recommendations is to form networks with other international actors. These networks will be constituted by ...

  1. Understanding Knowledge Network, Learning and Connectivism

    Science.gov (United States)

    AlDahdouh, Alaa A.; Osório, António J.; Caires, Susana

    2015-01-01

    Behaviorism, Cognitivism, Constructivism and other growing theories such as Actor-Network and Connectivism are circulating in the educational field. For each, there are allies who stand behind research evidence and consistency of observation. Meantime, those existing theories dominate the field until the background is changed or new concrete…

  2. From static to temporal network theory: Applications to functional brain connectivity

    Directory of Open Access Journals (Sweden)

    William Hedley Thompson

    2017-06-01

    Full Text Available Network neuroscience has become an established paradigm to tackle questions related to the functional and structural connectome of the brain. Recently, interest has been growing in examining the temporal dynamics of the brain’s network activity. Although different approaches to capturing fluctuations in brain connectivity have been proposed, there have been few attempts to quantify these fluctuations using temporal network theory. This theory is an extension of network theory that has been successfully applied to the modeling of dynamic processes in economics, social sciences, and engineering article but it has not been adopted to a great extent within network neuroscience. The objective of this article is twofold: (i to present a detailed description of the central tenets of temporal network theory and describe its measures, and; (ii to apply these measures to a resting-state fMRI dataset to illustrate their utility. Furthermore, we discuss the interpretation of temporal network theory in the context of the dynamic functional brain connectome. All the temporal network measures and plotting functions described in this article are freely available as the Python package Teneto. Temporal network theory is a subfield of network theory that has had limited application to date within network neuroscience. The aims of this work are to introduce temporal network theory, define the metrics relevant to the context of network neuroscience, and illustrate their potential by analyzing a resting-state fMRI dataset. We found both between-subjects and between-task differences that illustrate the potential for these tools to be applied in a wider context. Our tools for analyzing temporal networks have been released in a Python package called Teneto.

  3. Aggregated Computational Toxicology Resource (ACTOR)

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Aggregated Computational Toxicology Resource (ACTOR) is a database on environmental chemicals that is searchable by chemical name and other identifiers, and by...

  4. Review of network research in scientific journal ‘Entrepreneurship Theory and Practice’

    Directory of Open Access Journals (Sweden)

    Agnieszka Brzozowska

    2016-10-01

    Full Text Available This article aims at presenting a systematic review of publications that verified the network theory and the theory of networks empirically, published in the entrepreneurship journal with the highest Impact Factor: “Entrepreneurship Theory and Practice”. We present how publication frequency evolved over time, and classify papers into major streams of entrepreneurship research. Our findings suggest the theory of networks is an under-researched area promising for further advancing the theory of entrepreneurship. We also find increasing publication frequency of network related research over time. Results oriented research were most often present in reviewed articles, while relationship among network variables and innovation was only tested in two articles so far which suggests that more research is needed in this direction in the future. We belief that verification of theories of networks in entrepreneurship and verification of relationship between network variables and innovation within the network theory are most promising. The originality of this work lies in identification of research opportunities and dynamics of empirical verification of network studies in the field of entrepreneurship.

  5. Finding influential nodes for integration in brain networks using optimal percolation theory.

    Science.gov (United States)

    Del Ferraro, Gino; Moreno, Andrea; Min, Byungjoon; Morone, Flaviano; Pérez-Ramírez, Úrsula; Pérez-Cervera, Laura; Parra, Lucas C; Holodny, Andrei; Canals, Santiago; Makse, Hernán A

    2018-06-11

    Global integration of information in the brain results from complex interactions of segregated brain networks. Identifying the most influential neuronal populations that efficiently bind these networks is a fundamental problem of systems neuroscience. Here, we apply optimal percolation theory and pharmacogenetic interventions in vivo to predict and subsequently target nodes that are essential for global integration of a memory network in rodents. The theory predicts that integration in the memory network is mediated by a set of low-degree nodes located in the nucleus accumbens. This result is confirmed with pharmacogenetic inactivation of the nucleus accumbens, which eliminates the formation of the memory network, while inactivations of other brain areas leave the network intact. Thus, optimal percolation theory predicts essential nodes in brain networks. This could be used to identify targets of interventions to modulate brain function.

  6. Social Support Theory: A New Framework for Exploring Gender Differences in Business Owner Networks

    DEFF Research Database (Denmark)

    Neergaard, Helle

    The paper argues that to advance knowledge about small firm networks and consider the impact of gender, research should also consider the network experiences of women business owners. To engage in such research, this paper proposes a conceptual model of business owner networking which is informed...... by social support theory....

  7. Policy analysis of multi-actor systems

    CERN Document Server

    Enserink, Bert; Kwakkel, Jan; Thissen, Wil; Koppenjan, Joop; Bots, Pieter

    2010-01-01

    Policy analysts love solving complex problems. Their favorite problems are not just technically complex but also characterized by the presence of many different social actors that hold conflicting interests, objectives, and perceptions and act strategically to get the best out of a problem situation. This book offers guidance for policy analysts who want to assess if and how their analysis could be of help, based on the premise that problem formulation is the cornerstone in addressing complex problems. This book positions policy analysis within the theories on processes of policy making, and f

  8. Non-parametric Bayesian networks: Improving theory and reviewing applications

    International Nuclear Information System (INIS)

    Hanea, Anca; Morales Napoles, Oswaldo; Ababei, Dan

    2015-01-01

    Applications in various domains often lead to high dimensional dependence modelling. A Bayesian network (BN) is a probabilistic graphical model that provides an elegant way of expressing the joint distribution of a large number of interrelated variables. BNs have been successfully used to represent uncertain knowledge in a variety of fields. The majority of applications use discrete BNs, i.e. BNs whose nodes represent discrete variables. Integrating continuous variables in BNs is an area fraught with difficulty. Several methods that handle discrete-continuous BNs have been proposed in the literature. This paper concentrates only on one method called non-parametric BNs (NPBNs). NPBNs were introduced in 2004 and they have been or are currently being used in at least twelve professional applications. This paper provides a short introduction to NPBNs, a couple of theoretical advances, and an overview of applications. The aim of the paper is twofold: one is to present the latest improvements of the theory underlying NPBNs, and the other is to complement the existing overviews of BNs applications with the NPNBs applications. The latter opens the opportunity to discuss some difficulties that applications pose to the theoretical framework and in this way offers some NPBN modelling guidance to practitioners. - Highlights: • The paper gives an overview of the current NPBNs methodology. • We extend the NPBN methodology by relaxing the conditions of one of its fundamental theorems. • We propose improvements of the data mining algorithm for the NPBNs. • We review the professional applications of the NPBNs.

  9. Sigmund Freud-early network theories of the brain.

    Science.gov (United States)

    Surbeck, Werner; Killeen, Tim; Vetter, Johannes; Hildebrandt, Gerhard

    2018-06-01

    Since the early days of modern neuroscience, psychological models of brain function have been a key component in the development of new knowledge. These models aim to provide a framework that allows the integration of discoveries derived from the fundamental disciplines of neuroscience, including anatomy and physiology, as well as clinical neurology and psychiatry. During the initial stages of his career, Sigmund Freud (1856-1939), became actively involved in these nascent fields with a burgeoning interest in functional neuroanatomy. In contrast to his contemporaries, Freud was convinced that cognition could not be localised to separate modules and that the brain processes cognition not in a merely serial manner but in a parallel and dynamic fashion-anticipating fundamental aspects of current network theories of brain function. This article aims to shed light on Freud's seminal, yet oft-overlooked, early work on functional neuroanatomy and his reasons for finally abandoning the conventional neuroscientific "brain-based" reference frame in order to conceptualise the mind from a purely psychological perspective.

  10. Policy learning and policy networks in theory and practice: The role of policy brokers in the Indonesian biodiesel policy network

    NARCIS (Netherlands)

    M. Howlett (Michael); Mukherjee, I. (Ishani); J.F.M. Koppenjan (Joop)

    2017-01-01

    textabstractThis paper examines how learning has been treated, generally, in policy network theories and what questions have been posed, and answered, about this phenomenon to date. We examine to what extent network characteristics and especially the presence of various types of brokers impede or

  11. Transnational Diaspora and Civil Society Actors Driving MNE Internationalisation

    DEFF Research Database (Denmark)

    Rana, Mohammad Bakhtiar; Elo, Maria

    2016-01-01

    Multinational enterprises (MNEs) are viewed as proactive global economic actors that enter new and emerging markets with intentional strategies, building on their inherent resources and firm-specific advantages. However, an international joint venture involves numerous actors in the market entry...... and civil society actors. It provides evidence of the reactive internationalisation of an MNE, showing how the transnational diaspora drove the MNE’s internationalisation and how a civil society actor, in conjunction with a diaspora member, facilitated the creation of an international joint venture (IJV...... and organisational capability base for this process, which would not have happened without their market-driving and enabling influence. The findings illustrate the central role of transnational diaspora entrepreneurship and the related innovation, motivation, contextual intelligence, networking and funding...

  12. A Bayes Theory-Based Modeling Algorithm to End-to-end Network Traffic

    OpenAIRE

    Zhao Hong-hao; Meng Fan-bo; Zhao Si-wen; Zhao Si-hang; Lu Yi

    2016-01-01

    Recently, network traffic has exponentially increasing due to all kind of applications, such as mobile Internet, smart cities, smart transportations, Internet of things, and so on. the end-to-end network traffic becomes more important for traffic engineering. Usually end-to-end traffic estimation is highly difficult. This paper proposes a Bayes theory-based method to model the end-to-end network traffic. Firstly, the end-to-end network traffic is described as a independent identically distrib...

  13. You're a What? Voice Actor

    Science.gov (United States)

    Liming, Drew

    2009-01-01

    This article talks about voice actors and features Tony Oliver, a professional voice actor. Voice actors help to bring one's favorite cartoon and video game characters to life. They also do voice-overs for radio and television commercials and movie trailers. These actors use the sound of their voice to sell a character's emotions--or an advertised…

  14. Multicultural Monologues for Young Actors. The Young Actors Series.

    Science.gov (United States)

    Slaight, Craig, Ed.; Sharrar, Jack, Ed.

    This book presents 62 monologue selections from diverse cultures for young actors to perform. The book's selections offer "quality literature by significant writers." Some of the writers represented in the book are George C. Wolfe, Miguel Pinero, Lorraine Hansberry, Amiri Baraka (LeRoi Jones), John M. Synge, Yukio Mishima, Reynolds…

  15. An Actor and His Suitcase

    OpenAIRE

    Williams, Maurice

    2013-01-01

    The idea of the actor as journeyman is as old as the profession itself. The travel troupes of yesteryear laid the groundwork for the theatres of Shakespeare and the regional theatre circuit here in America. So if there is one thing an actor must have: it's a good suitcase. Or two. One for the rags and trinkets he, or she, holds dear; and another for all the skills he, or she, brings to every project.When I left the east coast for San Diego I brought with me those two suitcases. Luckily for me...

  16. Beyond Pain: Coercing Violent Non-State Actors

    Science.gov (United States)

    2010-01-01

    same collection by Abraham Maslow , “A Theory of Motivation,” 174- 175, taken from Psychological Review, 50 (1943). 15 For excellent study of global...utility now? Despite a persistent threat, contemporary theory and practice are not oriented on the VNSA problem. Focus remains on inter-state...actors make imperfect decisions resulting in unexpected behaviors. This is contrary to the underlying premise of classical coercion theory , which

  17. A theory of intelligence: networked problem solving in animal societies

    OpenAIRE

    Shour, Robert

    2009-01-01

    A society's single emergent, increasing intelligence arises partly from the thermodynamic advantages of networking the innate intelligence of different individuals, and partly from the accumulation of solved problems. Economic growth is proportional to the square of the network entropy of a society's population times the network entropy of the number of the society's solved problems.

  18. Towards an International Polar Data Coordination Network

    Directory of Open Access Journals (Sweden)

    P L Pulsifer

    2014-10-01

    Full Text Available Data management is integral to sound polar science. Through analysis of documents reporting on meetings of the Arctic data management community, a set of priorities and strategies are identified. These include the need to improve data sharing, make use of existing resources, and better engage stakeholders. Network theory is applied to a preliminary inventory of polar and global data management actors to improve understanding of the emerging community of practice. Under the name the Arctic Data Coordination Network, we propose a model network that can support the community in achieving their goals through improving connectivity between existing actors.

  19. On the Control of Consensus Networks: Theory and Applications

    Science.gov (United States)

    Hudoba de Badyn, Mathias

    Signed networks allow the study of positive and negative interactions between agents. In this thesis, three papers are presented that address controllability of networked dynamics. First, controllability of signed consensus networks is approached from a symmetry perspective, for both linear and nonlinear consensus protocols. It is shown that the graph-theoretic property of signed networks known as structural balance renders the consensus protocol uncontrollable when coupled with a certain type of symmetry. Stabilizability and output controllability of signed linear consensus is also examined, as well as a data-driven approach to finding bipartite consensus stemming from structural balance for signed nonlinear consensus. Second, an algorithm is constructed that allows one to grow a network while preserving controllability, and some generalizations of this algorithm are presented. Submodular optimization is used to analyze a second algorithm that adds nodes to a network to maximize the network connectivity.

  20. Identifying Key Actors in Heterogeneous Networks

    Science.gov (United States)

    2017-11-29

    Department of Defense (DOD) present social situations that are outside the scope and violate the assumptions of existing formal social science models. SNA by...assumptions of these existing social science models. SNA by its very construction focuses on dyadic relations and standard SNA metrics are focused only on...problematic for our purposes of determining relative valuations among vertices, but it is in contrast to the behavior of valuations like the Shapley value

  1. GCPSO in cooperation with graph theory to distribution network reconfiguration for energy saving

    International Nuclear Information System (INIS)

    Assadian, Mehdi; Farsangi, Malihe M.; Nezamabadi-pour, Hossein

    2010-01-01

    Network reconfiguration for loss reduction in distribution system is an important way to save energy. This paper investigates the ability of guaranteed convergence particle swarm optimization (GCPSO) and particle swarm optimization (PSO) in cooperation with graph theory for network reconfiguration to reduce the power loss and enhancement of voltage profile of distribution systems. Numerical results of three distribution systems are presented which illustrate the feasibility of the proposed method by GCPSO and PSO using the graph theory. To validate the obtained results, genetic algorithm (GA) using graph theory is also applied and is compared with the proposed GCPSO and PSO using graph theory.

  2. Self-similarity and scaling theory of complex networks

    Science.gov (United States)

    Song, Chaoming

    Scale-free networks have been studied extensively due to their relevance to many real systems as diverse as the World Wide Web (WWW), the Internet, biological and social networks. We present a novel approach to the analysis of scale-free networks, revealing that their structure is self-similar. This result is achieved by the application of a renormalization procedure which coarse-grains the system into boxes containing nodes within a given "size". Concurrently, we identify a power-law relation between the number of boxes needed to cover the network and the size of the box defining a self-similar exponent, which classifies fractal and non-fractal networks. By using the concept of renormalization as a mechanism for the growth of fractal and non-fractal modular networks, we show that the key principle that gives rise to the fractal architecture of networks is a strong effective "repulsion" between the most connected nodes (hubs) on all length scales, rendering them very dispersed. We show that a robust network comprised of functional modules, such as a cellular network, necessitates a fractal topology, suggestive of a evolutionary drive for their existence. These fundamental properties help to understand the emergence of the scale-free property in complex networks.

  3. EU–Hamas actors in a state of permanent liminality

    DEFF Research Database (Denmark)

    Pace, Michelle; Pallister-Wilkins, Polly

    2018-01-01

    This article contributes to the debate on liminality within International Relations (IR) theory by focusing on the actorness of the European Union (EU) and Hamas. The concept of liminality as a transitional process is applied to frame the situation of both the EU and Hamas as political actors in......-between socially established categories. This article explores how the liminal identity of these two actors impacts, on the one hand, their relations with each other and, on the other hand, their relations of ‘self’. Exploring the procedural relations of the EU and Hamas, it argues for the necessity of recognising...... liminal categories in IR theory and practice, while, at the same time, it highlights the limits of such in-between categories in a world order still structured around the state....

  4. Parallel Distributed Processing theory in the age of deep networks

    OpenAIRE

    Bowers, Jeffrey

    2017-01-01

    Parallel Distributed Processing (PDP) models in psychology are the precursors of deep networks used in computer science. However, only PDP models are associated with two core psychological claims, namely, that all knowledge is coded in a distributed format, and cognition is mediated by non-symbolic computations. These claims have long been debated within cognitive science, and recent work with deep networks speaks to this debate. Specifically, single-unit recordings show that deep networks le...

  5. Linking experiment and theory for three-dimensional networked binary metal nanoparticle–triblock terpolymer superstructures

    KAUST Repository

    Li, Zihui; Hur, Kahyun; Sai, Hiroaki; Higuchi, Takeshi; Takahara, Atsushi; Jinnai, Hiroshi; Gruner, Sol M.; Wiesner, Ulrich

    2014-01-01

    the intimate coupling of synthesis, in-depth electron tomographic characterization and theory enables exquisite control of superstructure in highly ordered porous three-dimensional continuous networks from single and binary mixtures of metal nanoparticles

  6. Mitigating Free Riding in Peer-To-Peer Networks: Game Theory ...

    African Journals Online (AJOL)

    Mitigating Free Riding in Peer-To-Peer Networks: Game Theory Approach. ... In this paper, we model the interactions between peers as a modified gift giving game and proposed an utility exchange incentive ... AJOL African Journals Online.

  7. Design of analog networks in the control theory formulation. Part 2: Numerical results

    OpenAIRE

    Zemliak, A. M.

    2005-01-01

    The paper presents numerical results of design of nonlinear electronic networks based on the problem formulation in terms of the control theory. Several examples illustrate the prospects of the approach suggested in the first part of the work.

  8. A social network model for the development of a 'Theory of Mind'

    Science.gov (United States)

    Harré, Michael S.

    2013-02-01

    A "Theory of Mind" is one of the most important skills we as humans have developed; It enables us to infer the mental states and intentions of others, build stable networks of relationships and it plays a central role in our psychological make-up and development. Findings published earlier this year have also shown that we as a species as well as each of us individually benefit from the enlargement of the underlying neuro-anatomical regions that support our social networks, mediated by our Theory of Mind that stabilises these networks. On the basis of such progress and that of earlier work, this paper draws together several different strands from psychology, behavioural economics and network theory in order to generate a novel theoretical representation of the development of our social-cognition and how subsequent larger social networks enables much of our cultural development but at the increased risk of mental disorders.

  9. Living Labs as boundary-spanners between Triple Helix actors

    NARCIS (Netherlands)

    van Geenhuizen, M.S.

    2016-01-01

    Living labs are an increasingly popular methodology to enhance innovation. Living labs aim to span boundaries between different organizations, among others Triple helix actors, by acting as a network organization typically in a real-life environment to foster co-creation by user-groups. This paper

  10. The network perspective: an integration of attachment and family systems theories.

    Science.gov (United States)

    Kozlowska, Kasia; Hanney, Lesley

    2002-01-01

    In this article we discuss the network paradigm as a useful base from which to integrate attachment and family systems theories. The network perspective refers to the application of general systems theory to living systems, and provides a framework that conceptualizes the dyadic and family systems as simultaneously distinct and interconnected. Network thinking requires that the clinician holds multiple perspectives in mind, considers each system level as both a part and a whole, and shifts the focus of attention between levels as required. Key epistemological issues that have hindered the integration of the theories are discussed. These include inconsistencies within attachment theory itself and confusion surrounding the theoretical conceptualizations of the relationship between attachment and family systems theories. Detailed information about attachment categories is provided using the Dynamic Maturational model. Case vignettes illustrating work with young children and their families explore the clinical implications of integrating attachment data into family therapy practice.

  11. Networking Theories on Giftedness--What We Can Learn from Synthesizing Renzulli's Domain General and Krutetskii's Mathematics-Specific Theory

    Science.gov (United States)

    Schindler, Maike; Rott, Benjamin

    2017-01-01

    Giftedness is an increasingly important research topic in educational sciences and mathematics education in particular. In this paper, we contribute to further theorizing mathematical giftedness through illustrating how networking processes can be conducted and illustrating their potential benefits. The paper focuses on two theories: Renzulli's…

  12. Inventory theory, mode choice and network structure in freight transport

    NARCIS (Netherlands)

    Combes, F.; Tavasszy, L.A.

    2016-01-01

    In passenger transport, hub-and-spoke networks allow the transportation of small passenger flows with competitive frequencies, in a way that direct line networks cannot. Equivalently, in freight transport, it can be expected that small shipper-receiver flows of high added value commodities transit

  13. Guide Actor-Critic for Continuous Control

    OpenAIRE

    Tangkaratt, Voot; Abdolmaleki, Abbas; Sugiyama, Masashi

    2017-01-01

    Actor-critic methods solve reinforcement learning problems by updating a parameterized policy known as an actor in a direction that increases an estimate of the expected return known as a critic. However, existing actor-critic methods only use values or gradients of the critic to update the policy parameter. In this paper, we propose a novel actor-critic method called the guide actor-critic (GAC). GAC firstly learns a guide actor that locally maximizes the critic and then it updates the polic...

  14. A Brief Historical Introduction to Euler's Formula for Polyhedra, Topology, Graph Theory and Networks

    Science.gov (United States)

    Debnath, Lokenath

    2010-01-01

    This article is essentially devoted to a brief historical introduction to Euler's formula for polyhedra, topology, theory of graphs and networks with many examples from the real-world. Celebrated Konigsberg seven-bridge problem and some of the basic properties of graphs and networks for some understanding of the macroscopic behaviour of real…

  15. A social network perspective on teacher collaboration in schools: Theory, methodology, and applications

    NARCIS (Netherlands)

    Moolenaar, Nienke

    2012-01-01

    An emerging trend in educational research is the use of social network theory and methodology to understand how teacher collaboration can support or constrain teaching, learning, and educational change. This article provides a critical synthesis of educational literature on school social networks

  16. Group field theory and tensor networks: towards a Ryu–Takayanagi formula in full quantum gravity

    Science.gov (United States)

    Chirco, Goffredo; Oriti, Daniele; Zhang, Mingyi

    2018-06-01

    We establish a dictionary between group field theory (thus, spin networks and random tensors) states and generalized random tensor networks. Then, we use this dictionary to compute the Rényi entropy of such states and recover the Ryu–Takayanagi formula, in two different cases corresponding to two different truncations/approximations, suggested by the established correspondence.

  17. Asymptotic theory of time varying networks with burstiness and heterogeneous activation patterns

    Science.gov (United States)

    Burioni, Raffaella; Ubaldi, Enrico; Vezzani, Alessandro

    2017-05-01

    The recent availability of large-scale, time-resolved and high quality digital datasets has allowed for a deeper understanding of the structure and properties of many real-world networks. The empirical evidence of a temporal dimension prompted the switch of paradigm from a static representation of networks to a time varying one. In this work we briefly review the framework of time-varying-networks in real world social systems, especially focusing on the activity-driven paradigm. We develop a framework that allows for the encoding of three generative mechanisms that seem to play a central role in the social networks’ evolution: the individual’s propensity to engage in social interactions, its strategy in allocate these interactions among its alters and the burstiness of interactions amongst social actors. The functional forms and probability distributions encoding these mechanisms are typically data driven. A natural question arises if different classes of strategies and burstiness distributions, with different local scale behavior and analogous asymptotics can lead to the same long time and large scale structure of the evolving networks. We consider the problem in its full generality, by investigating and solving the system dynamics in the asymptotic limit, for general classes of ties allocation mechanisms and waiting time probability distributions. We show that the asymptotic network evolution is driven by a few characteristics of these functional forms, that can be extracted from direct measurements on large datasets.

  18. Constructing a research network: accounting knowledge in production

    OpenAIRE

    Joannides , Vassili; Berland , Nicolas

    2013-01-01

    Avec Nicolas Berland; International audience; Purpose - This paper contributes to the sociology-of-science type of accounting literature, addressing how accounting knowledge is established, advanced and extended. Design/methodology/approach - The research question is answered through the example of research into linkages between accounting and religion. Adopting an Actor-Network Theory (ANT) approach, we follow the actors involved in the construction of accounting as an academic discipline th...

  19. Extending the theory of normative practices : an application to two cases of networked military operations

    NARCIS (Netherlands)

    Burken, van C.G.; Vries, de M.J.

    2012-01-01

    The theory of normative practices has proven to be helpful in eliciting the normative dimension of social practices. In this article we apply the theory to military practice. Since current military missions are Network Enabled Operations, which mandate a strong focus on cooperation with other

  20. Toward a generalized theory of epidemic awareness in social networks

    Science.gov (United States)

    Wu, Qingchu; Zhu, Wenfang

    We discuss the dynamics of a susceptible-infected-susceptible (SIS) model with local awareness in networks. Individual awareness to the infectious disease is characterized by a general function of epidemic information in its neighborhood. We build a high-accuracy approximate equation governing the spreading dynamics and derive an approximate epidemic threshold above which the epidemic spreads over the whole network. Our results extend the previous work and show that the epidemic threshold is dependent on the awareness function in terms of one infectious neighbor. Interestingly, when a pow-law awareness function is chosen, the epidemic threshold can emerge in infinite networks.

  1. Theory of fractional order elements based impedance matching networks

    KAUST Repository

    Radwan, Ahmed G.

    2011-03-01

    Fractional order circuit elements (inductors and capacitors) based impedance matching networks are introduced for the first time. In comparison to the conventional integer based L-type matching networks, fractional matching networks are much simpler and versatile. Any complex load can be matched utilizing a single series fractional element, which generally requires two elements for matching in the conventional approach. It is shown that all the Smith chart circles (resistance and reactance) are actually pairs of completely identical circles. They appear to be single for the conventional integer order case, where the identical circles completely overlap each other. The concept is supported by design equations and impedance matching examples. © 2010 IEEE.

  2. Literacy testing objects as co-actors in framing bilingual childrens literacy development

    DEFF Research Database (Denmark)

    Holm, Lars

    Literacy testing objects as co-actors in framing bilingual children´s literacy development Based on Latour´s theoretical perspective that human beings delegate roles and responsibility to artifacts, it becomes important to track and research the objects that circulate within and between “sites...... of human social interaction” (Latour, 2005). Latour argues that objects – e.g. a literacy testing instrument – play a central role through the meaning, human beings delegate to objects. In this way objects become co-actors in a network through the agency human actors delegate to them, and objects mediate...... categories and artifacts based on the local context. The second is termed “globalising connects” that brings local actors in line with bigger and remote networks. In order to understand the semiotic function of artifacts in a meaning making network an ethnographic oriented approach with a focus on actor...

  3. Animal Social Network Theory Can Help Wildlife Conservation

    NARCIS (Netherlands)

    Snijders, Lysanne; Blumstein, Daniel T.; Stanley, Christina R.; Franks, Daniel W.

    2017-01-01

    Many animals preferentially associate with certain other individuals. This social structuring can influence how populations respond to changes to their environment, thus making network analysis a promising technique for understanding, predicting, and potentially manipulating population dynamics.

  4. Design of Network Architectures: Role of Game Theory and Economics

    OpenAIRE

    Shetty, Nikhil

    2010-01-01

    The economics of the market that a network architecture enables has a important bearing on its success and eventual adoption. Some of these economic issues are tightly coupled with the design of the network architecture. A poor design could end up making certain markets very difficult to enable, even if they are in the better interest of society. Theanalysis of these cross-disciplinary problems requires understanding both the technology and the economic aspects. This thesis introduces three m...

  5. Leveraging percolation theory to single out influential spreaders in networks

    Science.gov (United States)

    Radicchi, Filippo; Castellano, Claudio

    2016-06-01

    Among the consequences of the disordered interaction topology underlying many social, technological, and biological systems, a particularly important one is that some nodes, just because of their position in the network, may have a disproportionate effect on dynamical processes mediated by the complex interaction pattern. For example, the early adoption of a commercial product by an opinion leader in a social network may change its fate or just a few superspreaders may determine the virality of a meme in social media. Despite many recent efforts, the formulation of an accurate method to optimally identify influential nodes in complex network topologies remains an unsolved challenge. Here, we present the exact solution of the problem for the specific, but highly relevant, case of the susceptible-infected-removed (SIR) model for epidemic spreading at criticality. By exploiting the mapping between bond percolation and the static properties of the SIR model, we prove that the recently introduced nonbacktracking centrality is the optimal criterion for the identification of influential spreaders in locally tree-like networks at criticality. By means of simulations on synthetic networks and on a very extensive set of real-world networks, we show that the nonbacktracking centrality is a highly reliable metric to identify top influential spreaders also in generic graphs not embedded in space and for noncritical spreading.

  6. Non-equilibrium mean-field theories on scale-free networks

    International Nuclear Information System (INIS)

    Caccioli, Fabio; Dall'Asta, Luca

    2009-01-01

    Many non-equilibrium processes on scale-free networks present anomalous critical behavior that is not explained by standard mean-field theories. We propose a systematic method to derive stochastic equations for mean-field order parameters that implicitly account for the degree heterogeneity. The method is used to correctly predict the dynamical critical behavior of some binary spin models and reaction–diffusion processes. The validity of our non-equilibrium theory is further supported by showing its relation with the generalized Landau theory of equilibrium critical phenomena on networks

  7. [Attachment theory and baby slings/carriers: technological network formation].

    Science.gov (United States)

    Lu, Zxy-Yann Jane; Lin, Wan-Shiuan

    2011-12-01

    Healthcare providers recognize the important role played by attachment theory in explaining the close relationship between mental health and social behavior in mothers and their children. This paper uses attachment theory in a socio-cultural context to ascertain the mechanism by which baby slings/carriers, a new technology, produced and reproduced the scientific motherhood. It further applies a social history of technology perspective to understand how baby carriers and attachment theory are socially constructed and historically contingent on three major transformations. These transformations include the use of attachment theory-based baby carriers to further scientific motherhood; the use of baby slings/carriers to further the medicalization of breastfeeding and enhance mother-infant attachment; and the use of baby slings/carriers to transform woman's identities by integrating scientific motherhood, independence and fashion. Implications for nursing clinical policy are suggested.

  8. Satisfaction with social networks: an examination of socioemotional selectivity theory across cohorts.

    Science.gov (United States)

    Lansford, J E; Sherman, A M; Antonucci, T C

    1998-12-01

    This study examines L. L. Carstensen's (1993, 1995) socioemotional selectivity theory within and across three cohorts spanning 4 decades. Socioemotional selectivity theory predicts that as individuals age, they narrow their social networks to devote more emotional resources to fewer relationships with close friends and family. Data from 3 cohorts of nationally representative samples were analyzed to determine whether respondents' satisfaction with the size of their social networks differed by age, cohort, or both. Results support socioemotional selectivity theory: More older adults than younger adults were satisfied with the current size of their social networks rather than wanting larger networks. These findings are consistent across all cohorts. Results are discussed with respect to social relationships across the life course.

  9. Engaging Actors in Co-Designing Heterogeneous Innovations

    DEFF Research Database (Denmark)

    Jørgensen, Ulrik; Lindegaard, Hanne; Rosenqvist, Tanja Schultz

    2011-01-01

    In this paper we share and analyze our experiences staging a co-design process in which we through different interventions engage important actors in designing. Our experiences are taking from an innovation and research project about user-involvement in textile design processes. As the project...... in our project’s agenda by going through the different stages of translation. The paper is finalized with reflections on the difficulties in engaging actors in a co-design process and transporting results into the existing framed context of design and architectural work....... related to translating and transporting the results of these different events due to the institutional and professional framing of projects and design processes. We are analyzing these through an actor network approach and use the translation term to describe how the participants slowly became engaged...

  10. Novel Congestion-Free Alternate Routing Path Scheme using Stackelberg Game Theory Model in Wireless Networks

    Directory of Open Access Journals (Sweden)

    P. Chitra

    2017-04-01

    Full Text Available Recently, wireless network technologies were designed for most of the applications. Congestion raised in the wireless network degrades the performance and reduces the throughput. Congestion-free network is quit essen- tial in the transport layer to prevent performance degradation in a wireless network. Game theory is a branch of applied mathematics and applied sciences that used in wireless network, political science, biology, computer science, philosophy and economics. e great challenges of wireless network are their congestion by various factors. E ective congestion-free alternate path routing is pretty essential to increase network performance. Stackelberg game theory model is currently employed as an e ective tool to design and formulate conges- tion issues in wireless networks. is work uses a Stackelberg game to design alternate path model to avoid congestion. In this game, leaders and followers are selected to select an alternate routing path. e correlated equilibrium is used in Stackelberg game for making better decision between non-cooperation and cooperation. Congestion was continuously monitored to increase the throughput in the network. Simulation results show that the proposed scheme could extensively improve the network performance by reducing congestion with the help of Stackelberg game and thereby enhance throughput.

  11. Automatic theory generation from analyst text files using coherence networks

    Science.gov (United States)

    Shaffer, Steven C.

    2014-05-01

    This paper describes a three-phase process of extracting knowledge from analyst textual reports. Phase 1 involves performing natural language processing on the source text to extract subject-predicate-object triples. In phase 2, these triples are then fed into a coherence network analysis process, using a genetic algorithm optimization. Finally, the highest-value sub networks are processed into a semantic network graph for display. Initial work on a well- known data set (a Wikipedia article on Abraham Lincoln) has shown excellent results without any specific tuning. Next, we ran the process on the SYNthetic Counter-INsurgency (SYNCOIN) data set, developed at Penn State, yielding interesting and potentially useful results.

  12. An Appraisal of Social Network Theory and Analysis as Applied to Public Health: Challenges and Opportunities.

    Science.gov (United States)

    Valente, Thomas W; Pitts, Stephanie R

    2017-03-20

    The use of social network theory and analysis methods as applied to public health has expanded greatly in the past decade, yielding a significant academic literature that spans almost every conceivable health issue. This review identifies several important theoretical challenges that confront the field but also provides opportunities for new research. These challenges include (a) measuring network influences, (b) identifying appropriate influence mechanisms, (c) the impact of social media and computerized communications, (d) the role of networks in evaluating public health interventions, and (e) ethics. Next steps for the field are outlined and the need for funding is emphasized. Recently developed network analysis techniques, technological innovations in communication, and changes in theoretical perspectives to include a focus on social and environmental behavioral influences have created opportunities for new theory and ever broader application of social networks to public health topics.

  13. An Energy-Efficient Game-Theory-Based Spectrum Decision Scheme for Cognitive Radio Sensor Networks.

    Science.gov (United States)

    Salim, Shelly; Moh, Sangman

    2016-06-30

    A cognitive radio sensor network (CRSN) is a wireless sensor network in which sensor nodes are equipped with cognitive radio. In this paper, we propose an energy-efficient game-theory-based spectrum decision (EGSD) scheme for CRSNs to prolong the network lifetime. Note that energy efficiency is the most important design consideration in CRSNs because it determines the network lifetime. The central part of the EGSD scheme consists of two spectrum selection algorithms: random selection and game-theory-based selection. The EGSD scheme also includes a clustering algorithm, spectrum characterization with a Markov chain, and cluster member coordination. Our performance study shows that EGSD outperforms the existing popular framework in terms of network lifetime and coordination overhead.

  14. An Energy-Efficient Game-Theory-Based Spectrum Decision Scheme for Cognitive Radio Sensor Networks

    Directory of Open Access Journals (Sweden)

    Shelly Salim

    2016-06-01

    Full Text Available A cognitive radio sensor network (CRSN is a wireless sensor network in which sensor nodes are equipped with cognitive radio. In this paper, we propose an energy-efficient game-theory-based spectrum decision (EGSD scheme for CRSNs to prolong the network lifetime. Note that energy efficiency is the most important design consideration in CRSNs because it determines the network lifetime. The central part of the EGSD scheme consists of two spectrum selection algorithms: random selection and game-theory-based selection. The EGSD scheme also includes a clustering algorithm, spectrum characterization with a Markov chain, and cluster member coordination. Our performance study shows that EGSD outperforms the existing popular framework in terms of network lifetime and coordination overhead.

  15. A game theory-based trust measurement model for social networks.

    Science.gov (United States)

    Wang, Yingjie; Cai, Zhipeng; Yin, Guisheng; Gao, Yang; Tong, Xiangrong; Han, Qilong

    2016-01-01

    In social networks, trust is a complex social network. Participants in online social networks want to share information and experiences with as many reliable users as possible. However, the modeling of trust is complicated and application dependent. Modeling trust needs to consider interaction history, recommendation, user behaviors and so on. Therefore, modeling trust is an important focus for online social networks. We propose a game theory-based trust measurement model for social networks. The trust degree is calculated from three aspects, service reliability, feedback effectiveness, recommendation credibility, to get more accurate result. In addition, to alleviate the free-riding problem, we propose a game theory-based punishment mechanism for specific trust and global trust, respectively. We prove that the proposed trust measurement model is effective. The free-riding problem can be resolved effectively through adding the proposed punishment mechanism.

  16. Decorated tensor network renormalization for lattice gauge theories and spin foam models

    International Nuclear Information System (INIS)

    Dittrich, Bianca; Mizera, Sebastian; Steinhaus, Sebastian

    2016-01-01

    Tensor network techniques have proved to be powerful tools that can be employed to explore the large scale dynamics of lattice systems. Nonetheless, the redundancy of degrees of freedom in lattice gauge theories (and related models) poses a challenge for standard tensor network algorithms. We accommodate for such systems by introducing an additional structure decorating the tensor network. This allows to explicitly preserve the gauge symmetry of the system under coarse graining and straightforwardly interpret the fixed point tensors. We propose and test (for models with finite Abelian groups) a coarse graining algorithm for lattice gauge theories based on decorated tensor networks. We also point out that decorated tensor networks are applicable to other models as well, where they provide the advantage to give immediate access to certain expectation values and correlation functions. (paper)

  17. Decorated tensor network renormalization for lattice gauge theories and spin foam models

    Science.gov (United States)

    Dittrich, Bianca; Mizera, Sebastian; Steinhaus, Sebastian

    2016-05-01

    Tensor network techniques have proved to be powerful tools that can be employed to explore the large scale dynamics of lattice systems. Nonetheless, the redundancy of degrees of freedom in lattice gauge theories (and related models) poses a challenge for standard tensor network algorithms. We accommodate for such systems by introducing an additional structure decorating the tensor network. This allows to explicitly preserve the gauge symmetry of the system under coarse graining and straightforwardly interpret the fixed point tensors. We propose and test (for models with finite Abelian groups) a coarse graining algorithm for lattice gauge theories based on decorated tensor networks. We also point out that decorated tensor networks are applicable to other models as well, where they provide the advantage to give immediate access to certain expectation values and correlation functions.

  18. A Bayes Theory-Based Modeling Algorithm to End-to-end Network Traffic

    Directory of Open Access Journals (Sweden)

    Zhao Hong-hao

    2016-01-01

    Full Text Available Recently, network traffic has exponentially increasing due to all kind of applications, such as mobile Internet, smart cities, smart transportations, Internet of things, and so on. the end-to-end network traffic becomes more important for traffic engineering. Usually end-to-end traffic estimation is highly difficult. This paper proposes a Bayes theory-based method to model the end-to-end network traffic. Firstly, the end-to-end network traffic is described as a independent identically distributed normal process. Then the Bases theory is used to characterize the end-to-end network traffic. By calculating the parameters, the model is determined correctly. Simulation results show that our approach is feasible and effective.

  19. Intra- Versus Intersex Aggression: Testing Theories of Sex Differences Using Aggression Networks.

    Science.gov (United States)

    Wölfer, Ralf; Hewstone, Miles

    2015-08-01

    Two theories offer competing explanations of sex differences in aggressive behavior: sexual-selection theory and social-role theory. While each theory has specific strengths and limitations depending on the victim's sex, research hardly differentiates between intrasex and intersex aggression. In the present study, 11,307 students (mean age = 14.96 years; 50% girls, 50% boys) from 597 school classes provided social-network data (aggression and friendship networks) as well as physical (body mass index) and psychosocial (gender and masculinity norms) information. Aggression networks were used to disentangle intra- and intersex aggression, whereas their class-aggregated sex differences were analyzed using contextual predictors derived from sexual-selection and social-role theories. As expected, results revealed that sexual-selection theory predicted male-biased sex differences in intrasex aggression, whereas social-role theory predicted male-biased sex differences in intersex aggression. Findings suggest the value of explaining sex differences separately for intra- and intersex aggression with a dual-theory framework covering both evolutionary and normative components. © The Author(s) 2015.

  20. Emergence and translations of management interests in corporate branding in the Finnish pulp and paper corporations : a study with an actor-network theory approach

    OpenAIRE

    Aspara, Jaakko

    2007-01-01

    The riddle of this Thesis is: How come the management of the Finnish pulp and paper (P&P) corporations became interested in corporate branding around the year 2000? By the Finnish P&P corporations, I refer particularly to the three large P&P corporations based in Finland in 2005: UPM-Kymmene, Stora Enso, and M-Real. By the management, I refer to managers of these corporations including the top managers, i.e. CEOs and executive board members, and even the members of the Boards of Directors. ...

  1. From cybercrime to cyborg crime : An exploration of high-tech cybercrime, offenders and victims through the lens of Actor-Network Theory

    NARCIS (Netherlands)

    van der Wagen, Wytske

    2018-01-01

    Universiteiten die worden gehackt, computersystemen die worden gegijzeld of tot ‘zombies’ gemaakt, servers van Internetproviders die worden gebombardeerd, we worden bijna dagelijks wel geconfronteerd met cybercrime en haar gevolgen. Deze meer technische vormen van criminaliteit wijken op

  2. Produsage in hybrid networks: sociotechnical skills in the case of Arduino

    Science.gov (United States)

    De Paoli, Stefano; Storni, Cristiano

    2011-04-01

    In 1this paper we investigate produsage using Actor-Network Theory with a focus on (produsage) skills, their development, and transformation. We argue that produsage is not a model that determines a change in the traditional consumption/production paradigm through a series of essential preconditions (such as open participation, peer-sharing, or common ownership). Rather, we explain produsage as the open-ended result of a series of heterogeneous actor-networking strategies. In this view, the so-called preconditions do not explain produsage but have to be explained along with its establishment as an actor-network. Drawing on this approach, we discuss a case study of an open hardware project: the Arduino board, and we develop a perspective that maps the skills of human and non-human entities in produsage actor-networks, showing how skills are symmetrical, relational, and circulating.

  3. Idea Management: Perspectives from Leadership, Learning, and Network Theory

    NARCIS (Netherlands)

    D. Deichmann (Dirk)

    2012-01-01

    textabstractIn this dissertation, we focus on how leadership styles, individual learning behaviors, and social network structures drive or inhibit organizational members to repeatedly generate and develop innovative ideas. Taking the idea management programs of three multinational companies as the

  4. Discretized kinetic theory on scale-free networks

    Science.gov (United States)

    Bertotti, Maria Letizia; Modanese, Giovanni

    2016-10-01

    The network of interpersonal connections is one of the possible heterogeneous factors which affect the income distribution emerging from micro-to-macro economic models. In this paper we equip our model discussed in [1, 2] with a network structure. The model is based on a system of n differential equations of the kinetic discretized-Boltzmann kind. The network structure is incorporated in a probabilistic way, through the introduction of a link density P(α) and of correlation coefficients P(β|α), which give the conditioned probability that an individual with α links is connected to one with β links. We study the properties of the equations and give analytical results concerning the existence, normalization and positivity of the solutions. For a fixed network with P(α) = c/α q , we investigate numerically the dependence of the detailed and marginal equilibrium distributions on the initial conditions and on the exponent q. Our results are compatible with those obtained from the Bouchaud-Mezard model and from agent-based simulations, and provide additional information about the dependence of the individual income on the level of connectivity.

  5. Macroscopic Fundamental Diagram for pedestrian networks : Theory and applications

    NARCIS (Netherlands)

    Hoogendoorn, S.P.; Daamen, W.; Knoop, V.L.; Steenbakkers, Jeroen; Sarvi, Majid

    2017-01-01

    The Macroscopic Fundamental diagram (MFD) has proven to be a powerful concept in understanding and managing vehicular network dynamics, both from a theoretical angle and from a more application-oriented perspective. In this contribution, we explore the existence and the characteristics of the

  6. Integrated service resource reservation using queueing networks theory

    DEFF Research Database (Denmark)

    Brewka, Lukasz Jerzy; Iversen, Villy Bæk; Kardaras, Georgios

    2014-01-01

    This study analyses multi-server multi-service queueing networks with service protection. To guarantee each service a certain quality-of-service and at the same time ensure high utilisation of servers, a minimum capacity is reserved each service. In addition, all services share the remaining non...

  7. Actor bonds after relationship dissolution

    DEFF Research Database (Denmark)

    Skaates, Maria Anne

    2000-01-01

    Most of the presented papers at the 1st NoRD Workshop can be classified as belonging to the business marketing approach to relationship dissolution. Two papers were conceptual, and the remaining six were empirical studies. The first conceptual study by Skaates (2000) focuses on the nature...... of the actor bonds that remain after a business relationship has ended. The study suggests that an interdisciplinary approach would provide a richer understanding of the phenomenon; this could be achieved by using e.g. Bourdieu's sociological concepts in dissolution research....

  8. Social contagion theory: examining dynamic social networks and human behavior

    OpenAIRE

    Christakis, Nicholas A.; Fowler, James H.

    2012-01-01

    Here, we review the research we have done on social contagion. We describe the methods we have employed (and the assumptions they have entailed) in order to examine several datasets with complementary strengths and weaknesses, including the Framingham Heart Study, the National Longitudinal Study of Adolescent Health, and other observational and experimental datasets that we and others have collected. We describe the regularities that led us to propose that human social networks may exhibit a ...

  9. Network organization is globally atypical in autism: A graph theory study of intrinsic functional connectivity.

    Science.gov (United States)

    Keown, Christopher L; Datko, Michael C; Chen, Colleen P; Maximo, José Omar; Jahedi, Afrooz; Müller, Ralph-Axel

    2017-01-01

    Despite abundant evidence of brain network anomalies in autism spectrum disorder (ASD), findings have varied from broad functional underconnectivity to broad overconnectivity. Rather than pursuing overly simplifying general hypotheses ('under' vs. 'over'), we tested the hypothesis of atypical network distribution in ASD (i.e., participation of unusual loci in distributed functional networks). We used a selective high-quality data subset from the ABIDE datashare (including 111 ASD and 174 typically developing [TD] participants) and several graph theory metrics. Resting state functional MRI data were preprocessed and analyzed for detection of low-frequency intrinsic signal correlations. Groups were tightly matched for available demographics and head motion. As hypothesized, the Rand Index (reflecting how similar network organization was to a normative set of networks) was significantly lower in ASD than TD participants. This was accounted for by globally reduced cohesion and density, but increased dispersion of networks. While differences in hub architecture did not survive correction, rich club connectivity (among the hubs) was increased in the ASD group. Our findings support the model of reduced network integration (connectivity with networks) and differentiation (or segregation; based on connectivity outside network boundaries) in ASD. While the findings applied at the global level, they were not equally robust across all networks and in one case (greater cohesion within ventral attention network in ASD) even reversed.

  10. Social contagion theory: examining dynamic social networks and human behavior.

    Science.gov (United States)

    Christakis, Nicholas A; Fowler, James H

    2013-02-20

    Here, we review the research we have conducted on social contagion. We describe the methods we have employed (and the assumptions they have entailed) to examine several datasets with complementary strengths and weaknesses, including the Framingham Heart Study, the National Longitudinal Study of Adolescent Health, and other observational and experimental datasets that we and others have collected. We describe the regularities that led us to propose that human social networks may exhibit a 'three degrees of influence' property, and we review statistical approaches we have used to characterize interpersonal influence with respect to phenomena as diverse as obesity, smoking, cooperation, and happiness. We do not claim that this work is the final word, but we do believe that it provides some novel, informative, and stimulating evidence regarding social contagion in longitudinally followed networks. Along with other scholars, we are working to develop new methods for identifying causal effects using social network data, and we believe that this area is ripe for statistical development as current methods have known and often unavoidable limitations. Copyright © 2012 John Wiley & Sons, Ltd.

  11. An analogue of Morse theory for planar linear networks and the generalized Steiner problem

    International Nuclear Information System (INIS)

    Karpunin, G A

    2000-01-01

    A study is made of the generalized Steiner problem: the problem of finding all the locally minimal networks spanning a given boundary set (terminal set). It is proposed to solve this problem by using an analogue of Morse theory developed here for planar linear networks. The space K of all planar linear networks spanning a given boundary set is constructed. The concept of a critical point and its index is defined for the length function l of a planar linear network. It is shown that locally minimal networks are local minima of l on K and are critical points of index 1. The theorem is proved that the sum of the indices of all the critical points is equal to χ(K)=1. This theorem is used to find estimates for the number of locally minimal networks spanning a given boundary set

  12. 网络经济的博弈论分析%Analysis of the Game Theory in Network Economy

    Institute of Scientific and Technical Information of China (English)

    王玉

    2001-01-01

    Based on the non-asymmetrical information game theory, this paper analyzes the trust-agency mechanism in network economy, the change of the rules of the game and the strategies of the game in the network environment.

  13. Identification of global oil trade patterns: An empirical research based on complex network theory

    International Nuclear Information System (INIS)

    Ji, Qiang; Zhang, Hai-Ying; Fan, Ying

    2014-01-01

    Highlights: • A global oil trade core network is analyzed using complex network theory. • The global oil export core network displays a scale-free behaviour. • The current global oil trade network can be divided into three trading blocs. • The global oil trade network presents a ‘robust and yet fragile’ characteristic. - Abstract: The Global oil trade pattern becomes increasingly complex, which has become one of the most important factors affecting every country’s energy strategy and economic development. In this paper, a global oil trade core network is constructed to analyze the overall features, regional characteristics and stability of the oil trade using complex network theory. The results indicate that the global oil export core network displays a scale-free behaviour, in which the trade position of nodes presents obvious heterogeneity and the ‘hub nodes’ play a ‘bridge’ role in the formation process of the trade network. The current global oil trade network can be divided into three trading blocs, including the ‘South America-West Africa-North America’ trading bloc, the ‘Middle East–Asian–Pacific region’ trading bloc, and ‘the former Soviet Union–North Africa–Europe’ trading bloc. Geopolitics and diplomatic relations are the two main reasons for this regional oil trade structure. Moreover, the global oil trade network presents a ‘robust but yet fragile’ characteristic, and the impacts of trade interruption always tend to spread throughout the whole network even if the occurrence of export disruptions is localised

  14. Managing Actors, Resources, and Activities in Innovation Ecosystems – A Design Science Approach

    OpenAIRE

    Valkokari , Katri; Amitrano , Cristina ,; Bifulco , Francesco; Valjakka , Tiina

    2016-01-01

    Part 13: Design Science and Business Models - Design Science Research; International audience; Through a design science approach, the paper explores how actors in a network create and sustain competitive advantage independently and through participation in a system of actors (i.e., a collaborative network) who are not hierarchically managed but, rather, act toward their own goals within the innovation ecosystem. In accordance with design studies, the relevance of research and its quality are ...

  15. The use of network theory to model disparate ship design information

    Directory of Open Access Journals (Sweden)

    Douglas Rigterink

    2014-06-01

    Full Text Available This paper introduces the use of network theory to model and analyze disparate ship design information. This work will focus on a ship's distributed systems and their intra- and intersystem structures and interactions. The three system to be analyzed are: a passageway system, an electrical system, and a fire fighting system. These systems will be analyzed individually using common network metrics to glean information regarding their structures and attributes. The systems will also be subjected to community detection algorithms both separately and as a multiplex network to compare their similarities, differences, and interactions. Network theory will be shown to be useful in the early design stage due to its simplicity and ability to model any shipboard system.

  16. The use of network theory to model disparate ship design information

    Science.gov (United States)

    Rigterink, Douglas; Piks, Rebecca; Singer, David J.

    2014-06-01

    This paper introduces the use of network theory to model and analyze disparate ship design information. This work will focus on a ship's distributed systems and their intra- and intersystem structures and interactions. The three system to be analyzed are: a passageway system, an electrical system, and a fire fighting system. These systems will be analyzed individually using common network metrics to glean information regarding their structures and attributes. The systems will also be subjected to community detection algorithms both separately and as a multiplex network to compare their similarities, differences, and interactions. Network theory will be shown to be useful in the early design stage due to its simplicity and ability to model any shipboard system.

  17. The use of network theory to model disparate ship design information

    Directory of Open Access Journals (Sweden)

    Rigterink Douglas

    2014-06-01

    Full Text Available This paper introduces the use of network theory to model and analyze disparate ship design information. This work will focus on a ship’s distributed systems and their intra- and intersystem structures and interactions. The three system to be analyzed are: a passageway system, an electrical system, and a fire fighting system. These systems will be analyzed individually using common network metrics to glean information regarding their structures and attributes. The systems will also be subjected to community detection algorithms both separately and as a multiplex network to compare their similarities, differences, and interactions. Network theory will be shown to be useful in the early design stage due to its simplicity and ability to model any shipboard system.

  18. Methodology for Simulation and Analysis of Complex Adaptive Supply Network Structure and Dynamics Using Information Theory

    Directory of Open Access Journals (Sweden)

    Joshua Rodewald

    2016-10-01

    Full Text Available Supply networks existing today in many industries can behave as complex adaptive systems making them more difficult to analyze and assess. Being able to fully understand both the complex static and dynamic structures of a complex adaptive supply network (CASN are key to being able to make more informed management decisions and prioritize resources and production throughout the network. Previous efforts to model and analyze CASN have been impeded by the complex, dynamic nature of the systems. However, drawing from other complex adaptive systems sciences, information theory provides a model-free methodology removing many of those barriers, especially concerning complex network structure and dynamics. With minimal information about the network nodes, transfer entropy can be used to reverse engineer the network structure while local transfer entropy can be used to analyze the network structure’s dynamics. Both simulated and real-world networks were analyzed using this methodology. Applying the methodology to CASNs allows the practitioner to capitalize on observations from the highly multidisciplinary field of information theory which provides insights into CASN’s self-organization, emergence, stability/instability, and distributed computation. This not only provides managers with a more thorough understanding of a system’s structure and dynamics for management purposes, but also opens up research opportunities into eventual strategies to monitor and manage emergence and adaption within the environment.

  19. Analysis of the enzyme network involved in cattle milk production using graph theory.

    Science.gov (United States)

    Ghorbani, Sholeh; Tahmoorespur, Mojtaba; Masoudi Nejad, Ali; Nasiri, Mohammad; Asgari, Yazdan

    2015-06-01

    Understanding cattle metabolism and its relationship with milk products is important in bovine breeding. A systemic view could lead to consequences that will result in a better understanding of existing concepts. Topological indices and quantitative characterizations mostly result from the application of graph theory on biological data. In the present work, the enzyme network involved in cattle milk production was reconstructed and analyzed based on available bovine genome information using several public datasets (NCBI, Uniprot, KEGG, and Brenda). The reconstructed network consisted of 3605 reactions named by KEGG compound numbers and 646 enzymes that catalyzed the corresponding reactions. The characteristics of the directed and undirected network were analyzed using Graph Theory. The mean path length was calculated to be4.39 and 5.41 for directed and undirected networks, respectively. The top 11 hub enzymes whose abnormality could harm bovine health and reduce milk production were determined. Therefore, the aim of constructing the enzyme centric network was twofold; first to find out whether such network followed the same properties of other biological networks, and second, to find the key enzymes. The results of the present study can improve our understanding of milk production in cattle. Also, analysis of the enzyme network can help improve the modeling and simulation of biological systems and help design desired phenotypes to increase milk production quality or quantity.

  20. Fundamentals of wireless sensor networks theory and practice

    CERN Document Server

    Dargie, Waltenegus

    2010-01-01

    In this book, the authors describe the fundamental concepts and practical aspects of wireless sensor networks. The book provides a comprehensive view to this rapidly evolving field, including its many novel applications, ranging from protecting civil infrastructure to pervasive health monitoring. Using detailed examples and illustrations, this book provides an inside track on the current state of the technology. The book is divided into three parts. In Part I, several node architectures, applications and operating systems are discussed. In Part II, the basic architectural frameworks, including

  1. A Cross-Layer Cooperation Mechanism of Wireless Networks Based on Game Theory

    OpenAIRE

    Chunsheng, Cui; Yongjian, Yang; Liping, Huang

    2014-01-01

    To meet the wireless network congestion control problem, we give a definition of congestion degree classification and propose a mechanism of directed cooperative path net, guided by the wireless network’s cross-layer design methods and node cooperation principles. Considering the virtual collision and “starved” phenomenon in congested networks, the QRD mechanism and channel competition mechanism QPCG are proposed, with introducing the game theory into the cross-layer design. Simulation result...

  2. Lithofacies identification using multiple adaptive resonance theory neural networks and group decision expert system

    Science.gov (United States)

    Chang, H.-C.; Kopaska-Merkel, D. C.; Chen, H.-C.; Rocky, Durrans S.

    2000-01-01

    Lithofacies identification supplies qualitative information about rocks. Lithofacies represent rock textures and are important components of hydrocarbon reservoir description. Traditional techniques of lithofacies identification from core data are costly and different geologists may provide different interpretations. In this paper, we present a low-cost intelligent system consisting of three adaptive resonance theory neural networks and a rule-based expert system to consistently and objectively identify lithofacies from well-log data. The input data are altered into different forms representing different perspectives of observation of lithofacies. Each form of input is processed by a different adaptive resonance theory neural network. Among these three adaptive resonance theory neural networks, one neural network processes the raw continuous data, another processes categorial data, and the third processes fuzzy-set data. Outputs from these three networks are then combined by the expert system using fuzzy inference to determine to which facies the input data should be assigned. Rules are prioritized to emphasize the importance of firing order. This new approach combines the learning ability of neural networks, the adaptability of fuzzy logic, and the expertise of geologists to infer facies of the rocks. This approach is applied to the Appleton Field, an oil field located in Escambia County, Alabama. The hybrid intelligence system predicts lithofacies identity from log data with 87.6% accuracy. This prediction is more accurate than those of single adaptive resonance theory networks, 79.3%, 68.0% and 66.0%, using raw, fuzzy-set, and categorical data, respectively, and by an error-backpropagation neural network, 57.3%. (C) 2000 Published by Elsevier Science Ltd. All rights reserved.

  3. Exploring the Combination of Dempster-Shafer Theory and Neural Network for Predicting Trust and Distrust

    Directory of Open Access Journals (Sweden)

    Xin Wang

    2016-01-01

    Full Text Available In social media, trust and distrust among users are important factors in helping users make decisions, dissect information, and receive recommendations. However, the sparsity and imbalance of social relations bring great difficulties and challenges in predicting trust and distrust. Meanwhile, there are numerous inducing factors to determine trust and distrust relations. The relationship among inducing factors may be dependency, independence, and conflicting. Dempster-Shafer theory and neural network are effective and efficient strategies to deal with these difficulties and challenges. In this paper, we study trust and distrust prediction based on the combination of Dempster-Shafer theory and neural network. We firstly analyze the inducing factors about trust and distrust, namely, homophily, status theory, and emotion tendency. Then, we quantify inducing factors of trust and distrust, take these features as evidences, and construct evidence prototype as input nodes of multilayer neural network. Finally, we propose a framework of predicting trust and distrust which uses multilayer neural network to model the implementing process of Dempster-Shafer theory in different hidden layers, aiming to overcome the disadvantage of Dempster-Shafer theory without optimization method. Experimental results on a real-world dataset demonstrate the effectiveness of the proposed framework.

  4. Parameter Networks: Towards a Theory of Low-level Vision,

    Science.gov (United States)

    1981-04-01

    edge in image space arid increment those points in an array. Figure 5 shows the relevant geometry . Figure 5: Geometry for the I Iough Transform. In...8217Iels suc(h ,-s thiose shown in 1ligure 7 to reorganize origami wo.d- figures. Figoure?7. 1’o show an example In detail, Kender’s techn!Ciue for...Compuiter Science Dept, Carnegie-.Mcllon U., October 1979. Kanade, Tl., "A theory of Origami world," CMU-CS-78-144, Computer Science Dept, Carnegie

  5. Mode 3 knowledge production: Systems and systems theory, clusters and networks

    OpenAIRE

    Carayannis, Elias G.; Campbell, David F. J.; Rehman, Scheherazade S.

    2016-01-01

    With the comprehensive term of "Mode 3," we want to draw a conceptual link between systems and systems theory and want to demonstrate further how this can be applied to knowledge in the next steps. Systems can be understood as being composed of "elements", which are tied together by a "self-rationale". For innovation, often innovation clusters and innovation networks are being regarded as important. By leveraging systems theory for innovation concepts, one can implement references between the...

  6. Translation Theory 'Translated'

    DEFF Research Database (Denmark)

    Wæraas, Arild; Nielsen, Jeppe

    2016-01-01

    Translation theory has proved to be a versatile analytical lens used by scholars working from different traditions. On the basis of a systematic literature review, this study adds to our understanding of the ‘translations’ of translation theory by identifying the distinguishing features of the most...... common theoretical approaches to translation within the organization and management discipline: actor-network theory, knowledge-based theory, and Scandinavian institutionalism. Although each of these approaches already has borne much fruit in research, the literature is diverse and somewhat fragmented......, but also overlapping. We discuss the ways in which the three versions of translation theory may be combined and enrich each other so as to inform future research, thereby offering a more complete understanding of translation in and across organizational settings....

  7. Analysis of radionuclide transport through fracture networks by percolation theory

    International Nuclear Information System (INIS)

    Ahn, Joonhong; Furuhama, Yutaka; Li, Yadong; Suzuki, Atsuyuki

    1991-01-01

    Presented are results of numerical simulations for radionuclide diffusion through fracture networks in geologic layers. Actual fracture networks are expressed as two-dimensional honeycomb percolation lattices. Random-walk simulations of diffusion on percolation lattices are made by the exact-enumeration method, and compared with those from Fickian diffusion with constant and decreasing diffusion coefficients. Mean-square displacement of a random-walker on percolation lattices increases more slowly with time than that for Fickian diffusion with the constant diffusion coefficient. Though the same relation of mean-square displacement vs. time as for the percolation lattices can be obtained for a continuum with decreasing diffusion coefficients, spatial distribution of probability densities of finding the random-walker on the percolation lattice differs from that on a continuum with the decreasing diffusion coefficient. The percolation model results in slow spreading near the origin and fast spreading in the outer region, whereas the decreasing-diffusion coefficient model shows the reverse because of smaller diffusion coefficient in the outer region. We could derive a general formula that can include both Fickian and anomalous diffusion in terms of fractal and fracton dimensionalities and the anomalous diffusion exponent. (author)

  8. Applying Game Theory in 802.11 Wireless Networks

    Directory of Open Access Journals (Sweden)

    Tomas Cuzanauskas

    2015-07-01

    Full Text Available IEEE 802.11 is one of the most popular wireless technologies in recent days. Due to easiness of adaption and relatively low cost the demand for IEEE 802.11 devices is increasing exponentially. IEEE works in two bands 2.4 GHz and 5 GHz, these bands are known as ISM band. The unlicensed bands are managed by authority which set simple rules to follow when using unlicensed bands, the rules includes requirements as maximum power, out-of-band emissions control as well as interference mitigation. However these rules became outdated as IEEE 802.11 technology is emerging and evolving in hours the rules aren’t well suited for current capabilities of IEEE 802.11 devices. In this article we present game theory based algorithm for IEEE 802.11 wireless devices, we will show that by using game theory it’s possible to achieve better usage of unlicensed spectrum as well as partially decline CSMA/CA. Finally by using this approach we might relax the currently applied maximum power rules for ISM bands, which enable IEEE 802.11 to work on longer distance and have better propagation characteristics.

  9. Ideas, actors and institutions: lessons from South Australian Health in All Policies on what encourages other sectors’ involvement

    Directory of Open Access Journals (Sweden)

    Fran Baum

    2017-10-01

    Full Text Available Abstract Background This paper examines the extent to which actors from sectors other than health engaged with the South Australian Health in All Policies (HiAP initiative, determines why they were prepared to do so and explains the mechanisms by which successful engagement happened. This examination applies theories of policy development and implementation. Methods The paper draws on a five year study of the implementation of HiAP comprising document analysis, a log of key events, detailed interviews with 64 policy actors and two surveys of public servants. Results The findings are analysed within an institutional policy analysis framework and examine the extent to which ideas, institutional factors and actor agency influenced the willingness of actors from other sectors to work with Health sector staff under the HiAP initiative. In terms of ideas, there was wide acceptance of the role of social determinants in shaping health and the importance of action to promote health in all government agencies. The institutional environment was initially supportive, but support waned over the course of the study when the economy in South Australia became less buoyant and a health minister less supportive of health promotion took office. The existence of a HiAP Unit was very helpful for gaining support from other sectors. A new Public Health Act offered some promise of institutionalising the HiAP approach and ideas. The analysis concludes that a key factor was the operation of a supportive network of public servants who promoted HiAP, including some who were senior and influential. Conclusions The South Australian case study demonstrates that despite institutional constraints and shifting political support within the health sector, HiAP gained traction in other sectors. The key factors that encouraged the commitment of others sectors to HiAP were the existence of a supportive, knowledgeable policy network, political support, institutionalisation of the

  10. Ideas, actors and institutions: lessons from South Australian Health in All Policies on what encourages other sectors' involvement.

    Science.gov (United States)

    Baum, Fran; Delany-Crowe, Toni; MacDougall, Colin; Lawless, Angela; van Eyk, Helen; Williams, Carmel

    2017-10-16

    This paper examines the extent to which actors from sectors other than health engaged with the South Australian Health in All Policies (HiAP) initiative, determines why they were prepared to do so and explains the mechanisms by which successful engagement happened. This examination applies theories of policy development and implementation. The paper draws on a five year study of the implementation of HiAP comprising document analysis, a log of key events, detailed interviews with 64 policy actors and two surveys of public servants. The findings are analysed within an institutional policy analysis framework and examine the extent to which ideas, institutional factors and actor agency influenced the willingness of actors from other sectors to work with Health sector staff under the HiAP initiative. In terms of ideas, there was wide acceptance of the role of social determinants in shaping health and the importance of action to promote health in all government agencies. The institutional environment was initially supportive, but support waned over the course of the study when the economy in South Australia became less buoyant and a health minister less supportive of health promotion took office. The existence of a HiAP Unit was very helpful for gaining support from other sectors. A new Public Health Act offered some promise of institutionalising the HiAP approach and ideas. The analysis concludes that a key factor was the operation of a supportive network of public servants who promoted HiAP, including some who were senior and influential. The South Australian case study demonstrates that despite institutional constraints and shifting political support within the health sector, HiAP gained traction in other sectors. The key factors that encouraged the commitment of others sectors to HiAP were the existence of a supportive, knowledgeable policy network, political support, institutionalisation of the ideas and approach, and balancing of the economic and social goals of

  11. Incorporating Contagion in Portfolio Credit Risk Models Using Network Theory

    Directory of Open Access Journals (Sweden)

    Ioannis Anagnostou

    2018-01-01

    Full Text Available Portfolio credit risk models estimate the range of potential losses due to defaults or deteriorations in credit quality. Most of these models perceive default correlation as fully captured by the dependence on a set of common underlying risk factors. In light of empirical evidence, the ability of such a conditional independence framework to accommodate for the occasional default clustering has been questioned repeatedly. Thus, financial institutions have relied on stressed correlations or alternative copulas with more extreme tail dependence. In this paper, we propose a different remedy—augmenting systematic risk factors with a contagious default mechanism which affects the entire universe of credits. We construct credit stress propagation networks and calibrate contagion parameters for infectious defaults. The resulting framework is implemented on synthetic test portfolios wherein the contagion effect is shown to have a significant impact on the tails of the loss distributions.

  12. The Role of Adolescent Development in Social Networking Site Use: Theory and Evidence

    Directory of Open Access Journals (Sweden)

    Drew P. Cingel

    2014-03-01

    Full Text Available Using survey data collected from 260 children, adolescents, and young adults between the ages of 9 and 26, this paper offers evidence for a relationship between social networking site use and Imaginary Audience, a developmental variable in which adolescents believe others are thinking about them at all times. Specifically, after controlling for a number of variables, results indicate a significant, positive relationship between social networking site use and Imaginary Audience ideation. Additionally, results indicate a positive relationship between Imaginary Audience ideation and Facebook customization practices. Together, these findings provide evidence, based on Vygotskian developmental theory, for a general consideration of the role that currently available tools, in this case social networking sites, can have on development. Thus, findings implicate both the role of development on social networking site use, as well as the role of social networking site use on development. Overall, these findings have important implications for the study of media and human development, which are discussed in detail.

  13. Modelling the rebound effect with network theory: An insight into the European freight transport sector

    International Nuclear Information System (INIS)

    Ruzzenenti, Franco; Basosi, Riccardo

    2017-01-01

    This paper presents a two pronged approach to the study of the rebound effect, with the aim of assessing the magnitude of the effect in the European freight transport sector and proposing a new modelling framework based on network theory. The (direct) rebound effect is assessed with: 1) an econometric regression; 2) a model based on network theory and statistical mechanics. According to the econometric model the European road freight transport sector undergone a negative rebound between of −74% between 1998 and 2007 and −146% between 1998 and 2011. The network analysis delivers an estimation of network rebound ranging between −29.37% and −7.25. Overall, these results indicate that energy efficiency in Europe, between 1998 and 2011, succeed in reducing the energy consumptions amid an increasing demand for transports. Results on rebound estimation depend on the decision of using GDP as an exogenous variable, an assumption that leaves questions open about the causality chain between growth and transports. Furthermore, the network analysis highlights a structural change –a migration of production factors offshore, that might partially explain this negative effect. In this view, rebound effect analysis on a local or regional scale is becoming more and more uncertain in a globally interconnected economic context. - Highlights: • An evaluation of direct rebound effect in the freight transports with an econometric model is performed. • A new concept of rebound effect based on network theory is presented and implemented. • A comparative analysis of the two different approaches is developed. • Both models indicate that the there was a negative rebound effect in European freight transports. • Network theory proved to be a promising approach to energy systems and rebound effect modelling.

  14. Cyberspace: Malevolent Actors, Criminal Opportunities, and Strategic Competition

    Science.gov (United States)

    2016-08-01

    local wireless network to in- form the doctor, relatives, or other caregivers that the medications have been taken. In this way, computer chips have...labeled this phenomenon BlackFor, or Black Force, defined as a “postmodern form of societal cancer ,” and as “a confederation of illicit non-state actors...psychedelics, pre- 298 scription, precursors, opioids, ecstasy, cannabis , and steroids.61 Once these products were purchased, they were shipped in

  15. Human behavior understanding in networked sensing theory and applications of networks of sensors

    CERN Document Server

    Spagnolo, Paolo; Distante, Cosimo

    2014-01-01

    This unique text/reference provides a broad overview of both the technical challenges in sensor network development, and the real-world applications of distributed sensing. Important aspects of distributed computing in large-scale networked sensor systems are analyzed in the context of human behavior understanding, including such topics as systems design tools and techniques, in-network signals, and information processing. Additionally, the book examines a varied range of application scenarios, covering surveillance, indexing and retrieval, patient care, industrial safety, social and ambient

  16. Development of Novel Random Network Theory-Based Approaches to Identify Network Interactions among Nitrifying Bacteria

    Energy Technology Data Exchange (ETDEWEB)

    Shi, Cindy

    2015-07-17

    The interactions among different microbial populations in a community could play more important roles in determining ecosystem functioning than species numbers and their abundances, but very little is known about such network interactions at a community level. The goal of this project is to develop novel framework approaches and associated software tools to characterize the network interactions in microbial communities based on high throughput, large scale high-throughput metagenomics data and apply these approaches to understand the impacts of environmental changes (e.g., climate change, contamination) on network interactions among different nitrifying populations and associated microbial communities.

  17. Functional brain networks contributing to the Parieto-Frontal Integration Theory of Intelligence.

    Science.gov (United States)

    Vakhtin, Andrei A; Ryman, Sephira G; Flores, Ranee A; Jung, Rex E

    2014-12-01

    The refinement of localization of intelligence in the human brain is converging onto a distributed network that broadly conforms to the Parieto-Frontal Integration Theory (P-FIT). While this theory has received support in the neuroimaging literature, no functional magnetic resonance imaging study to date has conducted a whole-brain network-wise examination of the changes during engagement in tasks that are reliable measures of general intelligence (e.g., Raven's Progressive Matrices Test; RPM). Seventy-nine healthy subjects were scanned while solving RPM problems and during rest. Functional networks were extracted from the RPM and resting state data using Independent Component Analysis. Twenty-nine networks were identified, 26 of which were detected in both conditions. Fourteen networks were significantly correlated with the RPM task. The networks' spatial maps and functional connectivity measures at 3 frequency levels (low, medium, & high) were compared between the RPM and rest conditions. The regions involved in the networks that were found to be task related were consistent with the P-FIT, localizing to the bilateral medial frontal and parietal regions, right superior frontal lobule, and the right cingulate gyrus. Functional connectivity in multiple component pairs was differentially affected across all frequency levels during the RPM task. Our findings demonstrate that functional brain networks are more stable than previously thought, and maintain their general features across resting state and engagement in a complex cognitive task. The described spatial and functional connectivity alterations that such components undergo during fluid reasoning provide a network-wise framework of the P-FIT that can be valuable for further, network based, neuroimaging inquiries regarding the neural underpinnings of intelligence. Published by Elsevier Inc.

  18. Game Theory Meets Wireless Sensor Networks Security Requirements and Threats Mitigation: A Survey.

    Science.gov (United States)

    Abdalzaher, Mohamed S; Seddik, Karim; Elsabrouty, Maha; Muta, Osamu; Furukawa, Hiroshi; Abdel-Rahman, Adel

    2016-06-29

    We present a study of using game theory for protecting wireless sensor networks (WSNs) from selfish behavior or malicious nodes. Due to scalability, low complexity and disseminated nature of WSNs, malicious attacks can be modeled effectively using game theory. In this study, we survey the different game-theoretic defense strategies for WSNs. We present a taxonomy of the game theory approaches based on the nature of the attack, whether it is caused by an external attacker or it is the result of an internal node acting selfishly or maliciously. We also present a general trust model using game theory for decision making. We, finally, identify the significant role of evolutionary games for WSNs security against intelligent attacks; then, we list several prospect applications of game theory to enhance the data trustworthiness and node cooperation in different WSNs.

  19. Game Theory Meets Wireless Sensor Networks Security Requirements and Threats Mitigation: A Survey

    Directory of Open Access Journals (Sweden)

    Mohamed S. Abdalzaher

    2016-06-01

    Full Text Available We present a study of using game theory for protecting wireless sensor networks (WSNs from selfish behavior or malicious nodes. Due to scalability, low complexity and disseminated nature of WSNs, malicious attacks can be modeled effectively using game theory. In this study, we survey the different game-theoretic defense strategies for WSNs. We present a taxonomy of the game theory approaches based on the nature of the attack, whether it is caused by an external attacker or it is the result of an internal node acting selfishly or maliciously. We also present a general trust model using game theory for decision making. We, finally, identify the significant role of evolutionary games for WSNs security against intelligent attacks; then, we list several prospect applications of game theory to enhance the data trustworthiness and node cooperation in different WSNs.

  20. Time dependent mechanical modeling for polymers based on network theory

    Energy Technology Data Exchange (ETDEWEB)

    Billon, Noëlle [MINES ParisTech, PSL-Research University, CEMEF – Centre de mise en forme des matériaux, CNRS UMR 7635, CS 10207 rue Claude Daunesse 06904 Sophia Antipolis Cedex (France)

    2016-05-18

    Despite of a lot of attempts during recent years, complex mechanical behaviour of polymers remains incompletely modelled, making industrial design of structures under complex, cyclic and hard loadings not totally reliable. The non linear and dissipative viscoelastic, viscoplastic behaviour of those materials impose to take into account non linear and combined effects of mechanical and thermal phenomena. In this view, a visco-hyperelastic, viscoplastic model, based on network description of the material has recently been developed and designed in a complete thermodynamic frame in order to take into account those main thermo-mechanical couplings. Also, a way to account for coupled effects of strain-rate and temperature was suggested. First experimental validations conducted in the 1D limit on amorphous rubbery like PMMA in isothermal conditions led to pretty goods results. In this paper a more complete formalism is presented and validated in the case of a semi crystalline polymer, a PA66 and a PET (either amorphous or semi crystalline) are used. Protocol for identification of constitutive parameters is described. It is concluded that this new approach should be the route to accurately model thermo-mechanical behaviour of polymers using a reduced number of parameters of some physical meaning.

  1. Efficient computation in networks of spiking neurons: simulations and theory

    International Nuclear Information System (INIS)

    Natschlaeger, T.

    1999-01-01

    One of the most prominent features of biological neural systems is that individual neurons communicate via short electrical pulses, the so called action potentials or spikes. In this thesis we investigate possible mechanisms which can in principle explain how complex computations in spiking neural networks (SNN) can be performed very fast, i.e. within a few 10 milliseconds. Some of these models are based on the assumption that relevant information is encoded by the timing of individual spikes (temporal coding). We will also discuss a model which is based on a population code and still is able to perform fast complex computations. In their natural environment biological neural systems have to process signals with a rich temporal structure. Hence it is an interesting question how neural systems process time series. In this context we explore possible links between biophysical characteristics of single neurons (refractory behavior, connectivity, time course of postsynaptic potentials) and synapses (unreliability, dynamics) on the one hand and possible computations on times series on the other hand. Furthermore we describe a general model of computation that exploits dynamic synapses. This model provides a general framework for understanding how neural systems process time-varying signals. (author)

  2. A game theory approach to target tracking in sensor networks.

    Science.gov (United States)

    Gu, Dongbing

    2011-02-01

    In this paper, we investigate a moving-target tracking problem with sensor networks. Each sensor node has a sensor to observe the target and a processor to estimate the target position. It also has wireless communication capability but with limited range and can only communicate with neighbors. The moving target is assumed to be an intelligent agent, which is "smart" enough to escape from the detection by maximizing the estimation error. This adversary behavior makes the target tracking problem more difficult. We formulate this target estimation problem as a zero-sum game in this paper and use a minimax filter to estimate the target position. The minimax filter is a robust filter that minimizes the estimation error by considering the worst case noise. Furthermore, we develop a distributed version of the minimax filter for multiple sensor nodes. The distributed computation is implemented via modeling the information received from neighbors as measurements in the minimax filter. The simulation results show that the target tracking algorithm proposed in this paper provides a satisfactory result.

  3. Network Theory: A Primer and Questions for Air Transportation Systems Applications

    Science.gov (United States)

    Holmes, Bruce J.

    2004-01-01

    A new understanding (with potential applications to air transportation systems) has emerged in the past five years in the scientific field of networks. This development emerges in large part because we now have a new laboratory for developing theories about complex networks: The Internet. The premise of this new understanding is that most complex networks of interest, both of nature and of human contrivance, exhibit a fundamentally different behavior than thought for over two hundred years under classical graph theory. Classical theory held that networks exhibited random behavior, characterized by normal, (e.g., Gaussian or Poisson) degree distributions of the connectivity between nodes by links. The new understanding turns this idea on its head: networks of interest exhibit scale-free (or small world) degree distributions of connectivity, characterized by power law distributions. The implications of scale-free behavior for air transportation systems include the potential that some behaviors of complex system architectures might be analyzed through relatively simple approximations of local elements of the system. For air transportation applications, this presentation proposes a framework for constructing topologies (architectures) that represent the relationships between mobility, flight operations, aircraft requirements, and airspace capacity, and the related externalities in airspace procedures and architectures. The proposed architectures or topologies may serve as a framework for posing comparative and combinative analyses of performance, cost, security, environmental, and related metrics.

  4. Modeling and dynamical topology properties of VANET based on complex networks theory

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Hong; Li, Jie, E-mail: prof.li@foxmail.com [School of Civil Engineering and Mechanics, Huazhong University of Science and Technology, Wuhan, 430074 (China)

    2015-01-15

    Vehicular Ad hoc Network (VANET) is a special subset of multi-hop Mobile Ad hoc Networks in which vehicles can not only communicate with each other but also with the fixed equipments along the roads through wireless interfaces. Recently, it has been discovered that essential systems in real world share similar properties. When they are regarded as networks, among which the dynamic topology structure of VANET system is an important issue. Many real world networks are actually growing with preferential attachment like Internet, transportation system and telephone network. Those phenomena have brought great possibility in finding a strategy to calibrate and control the topology parameters which can help find VANET topology change regulation to relieve traffic jam, prevent traffic accident and improve traffic safety. VANET is a typical complex network which has its basic characteristics. In this paper, we focus on the macroscopic Vehicle-to-Infrastructure (V2I) and Vehicle-to-Vehicle (V2V) inter-vehicle communication network with complex network theory. In particular, this paper is the first one to propose a method analyzing the topological structure and performance of VANET and present the communications in VANET from a new perspective. Accordingly, we propose degree distribution, clustering coefficient and the short path length of complex network to implement our strategy by numerical example and simulation. All the results demonstrate that VANET shows small world network features and is characterized by a truncated scale-free degree distribution with power-law degree distribution. The average path length of the network is simulated numerically, which indicates that the network shows small-world property and is rarely affected by the randomness. What’s more, we carry out extensive simulations of information propagation and mathematically prove the power law property when γ > 2. The results of this study provide useful information for VANET optimization from a

  5. Combining evolutionary game theory and network theory to analyze human cooperation patterns

    International Nuclear Information System (INIS)

    Scatà, Marialisa; Di Stefano, Alessandro; La Corte, Aurelio; Liò, Pietro; Catania, Emanuele; Guardo, Ermanno; Pagano, Salvatore

    2016-01-01

    Highlights: • We investigate the evolutionary dynamics of human cooperation in a social network. • We introduce the concepts of “Critical Mass”, centrality measure and homophily. • The emergence of cooperation is affected by the spatial choice of the “Critical Mass”. • Our findings show that homophily speeds up the convergence towards cooperation. • Centrality and “Critical Mass” spatial choice partially offset the impact of homophily. - Abstract: As natural systems continuously evolve, the human cooperation dilemma represents an increasingly more challenging question. Humans cooperate in natural and social systems, but how it happens and what are the mechanisms which rule the emergence of cooperation, represent an open and fascinating issue. In this work, we investigate the evolution of cooperation through the analysis of the evolutionary dynamics of behaviours within the social network, where nodes can choose to cooperate or defect following the classical social dilemmas represented by Prisoner’s Dilemma and Snowdrift games. To this aim, we introduce a sociological concept and statistical estimator, “Critical Mass”, to detect the minimum initial seed of cooperators able to trigger the diffusion process, and the centrality measure to select within the social network. Selecting different spatial configurations of the Critical Mass nodes, we highlight how the emergence of cooperation can be influenced by this spatial choice of the initial core in the network. Moreover, we target to shed light how the concept of homophily, a social shaping factor for which “birds of a feather flock together”, can affect the evolutionary process. Our findings show that homophily allows speeding up the diffusion process and make quicker the convergence towards human cooperation, while centrality measure and thus the Critical Mass selection, play a key role in the evolution showing how the spatial configurations can create some hidden patterns, partially

  6. Protein Signaling Networks from Single Cell Fluctuations and Information Theory Profiling

    Science.gov (United States)

    Shin, Young Shik; Remacle, F.; Fan, Rong; Hwang, Kiwook; Wei, Wei; Ahmad, Habib; Levine, R.D.; Heath, James R.

    2011-01-01

    Protein signaling networks among cells play critical roles in a host of pathophysiological processes, from inflammation to tumorigenesis. We report on an approach that integrates microfluidic cell handling, in situ protein secretion profiling, and information theory to determine an extracellular protein-signaling network and the role of perturbations. We assayed 12 proteins secreted from human macrophages that were subjected to lipopolysaccharide challenge, which emulates the macrophage-based innate immune responses against Gram-negative bacteria. We characterize the fluctuations in protein secretion of single cells, and of small cell colonies (n = 2, 3,···), as a function of colony size. Measuring the fluctuations permits a validation of the conditions required for the application of a quantitative version of the Le Chatelier's principle, as derived using information theory. This principle provides a quantitative prediction of the role of perturbations and allows a characterization of a protein-protein interaction network. PMID:21575571

  7. Learning network theory : its contribution to our understanding of work-based learning projects and learning climate

    NARCIS (Netherlands)

    Poell, R.F.; Moorsel, M.A.A.H. van

    1996-01-01

    This paper discusses the relevance of Van der Krogt's learning network theory (1995) for our understanding of the concepts of work-related learning projects and learning climate in organisations. The main assumptions of the learning network theory are presented and transferred to the level of

  8. Network theory-based analysis of risk interactions in large engineering projects

    International Nuclear Information System (INIS)

    Fang, Chao; Marle, Franck; Zio, Enrico; Bocquet, Jean-Claude

    2012-01-01

    This paper presents an approach based on network theory to deal with risk interactions in large engineering projects. Indeed, such projects are exposed to numerous and interdependent risks of various nature, which makes their management more difficult. In this paper, a topological analysis based on network theory is presented, which aims at identifying key elements in the structure of interrelated risks potentially affecting a large engineering project. This analysis serves as a powerful complement to classical project risk analysis. Its originality lies in the application of some network theory indicators to the project risk management field. The construction of the risk network requires the involvement of the project manager and other team members assigned to the risk management process. Its interpretation improves their understanding of risks and their potential interactions. The outcomes of the analysis provide a support for decision-making regarding project risk management. An example of application to a real large engineering project is presented. The conclusion is that some new insights can be found about risks, about their interactions and about the global potential behavior of the project. - Highlights: ► The method addresses the modeling of complexity in project risk analysis. ► Network theory indicators enable other risks than classical criticality analysis to be highlighted. ► This topological analysis improves project manager's understanding of risks and risk interactions. ► This helps project manager to make decisions considering the position in the risk network. ► An application to a real tramway implementation project in a city is provided.

  9. Endogenous Molecular-Cellular Network Cancer Theory: A Systems Biology Approach.

    Science.gov (United States)

    Wang, Gaowei; Yuan, Ruoshi; Zhu, Xiaomei; Ao, Ping

    2018-01-01

    In light of ever apparent limitation of the current dominant cancer mutation theory, a quantitative hypothesis for cancer genesis and progression, endogenous molecular-cellular network hypothesis has been proposed from the systems biology perspective, now for more than 10 years. It was intended to include both the genetic and epigenetic causes to understand cancer. Its development enters the stage of meaningful interaction with experimental and clinical data and the limitation of the traditional cancer mutation theory becomes more evident. Under this endogenous network hypothesis, we established a core working network of hepatocellular carcinoma (HCC) according to the hypothesis and quantified the working network by a nonlinear dynamical system. We showed that the two stable states of the working network reproduce the main known features of normal liver and HCC at both the modular and molecular levels. Using endogenous network hypothesis and validated working network, we explored genetic mutation pattern in cancer and potential strategies to cure or relieve HCC from a totally new perspective. Patterns of genetic mutations have been traditionally analyzed by posteriori statistical association approaches in light of traditional cancer mutation theory. One may wonder the possibility of a priori determination of any mutation regularity. Here, we found that based on the endogenous network theory the features of genetic mutations in cancers may be predicted without any prior knowledge of mutation propensities. Normal hepatocyte and cancerous hepatocyte stable states, specified by distinct patterns of expressions or activities of proteins in the network, provide means to directly identify a set of most probable genetic mutations and their effects in HCC. As the key proteins and main interactions in the network are conserved through cell types in an organism, similar mutational features may also be found in other cancers. This analysis yielded straightforward and testable

  10. An application of the graph theory which examines the metro networks

    Directory of Open Access Journals (Sweden)

    Svetla STOILOVA

    2015-06-01

    Full Text Available The graph theory gives a mathematical representation of transport networks and allows us to study their characteristics effectively. A research of the structure of metro system has been conducted in the study by using the graph theory. The study includes subway systems of 22 European capitals. New indicators have been defined in the research such as a degree of routing, a connectivity of the route, average length per link (which takes into account the number of routes, intensity of the route, density of the route. The new and the existing indicators have been used to analyze and classify the metro networks. The statistical method cluster analysis has been applied to classify the networks. Ten indicators have been used to carry out an analysis. The metro systems in European capitals have been classified in three clusters. The first cluster includes large metro systems, the second one includes small metro networks whereas the third cluster includes metro networks with only one line. The combination of both two methods has been used for the first time in this research. The methodology could be used to evaluate other existing metro networks as well as for preliminary analysis in the design of subway systems.

  11. Actor Bonds in Situations of Discontinuous Business Activities

    DEFF Research Database (Denmark)

    Skaates, Maria Anne

    2000-01-01

    Demand in many industrial buying situations, e.g. project purchases or procurement related to virtual organizations, is discontinuous. In situations of discontinuity, networks are often more of an ad hos informational and social nature, as strong activity and resource links are not present....... Furthermore the governance structure of markets characterized by discontinuous business activities is either that of the "socially constructed market" (Skaates, 2000) or that of the (socially constructed) network (Håkansson and Johanson, 1993). Additionally relationships and actor bonds vary substantially...

  12. Game theory and extremal optimization for community detection in complex dynamic networks.

    Science.gov (United States)

    Lung, Rodica Ioana; Chira, Camelia; Andreica, Anca

    2014-01-01

    The detection of evolving communities in dynamic complex networks is a challenging problem that recently received attention from the research community. Dynamics clearly add another complexity dimension to the difficult task of community detection. Methods should be able to detect changes in the network structure and produce a set of community structures corresponding to different timestamps and reflecting the evolution in time of network data. We propose a novel approach based on game theory elements and extremal optimization to address dynamic communities detection. Thus, the problem is formulated as a mathematical game in which nodes take the role of players that seek to choose a community that maximizes their profit viewed as a fitness function. Numerical results obtained for both synthetic and real-world networks illustrate the competitive performance of this game theoretical approach.

  13. Network Framing of Pest Management Knowledge and Practice

    Science.gov (United States)

    Moore, Keith M.

    2008-01-01

    Conventional technology transfer is based on the assumption that autonomous individuals independently make behavioral decisions. In contrast, Actor-Network Theory (ANT) suggests that people and technologies are interconnected in ways that reinforce and reproduce some types of knowledge and consequent behavioral practices, but not others. Research…

  14. Technology assessment, expectations and networks : An illustration using new materials

    NARCIS (Netherlands)

    Den Hond, Frank; Groenewegen, Peter; Vergragt, Philip

    1990-01-01

    This presents an approach to forecasting and identifying the positive and negative consequences of a new technology. It outlines aspects of the theory of actor networks, and shows how it can help the analysis. As a specific example, to aid communication, it considers new materials technology

  15. Learning Networks and the Journey of "Becoming Doctor"

    Science.gov (United States)

    Barnacle, Robyn; Mewburn, Inger

    2010-01-01

    Scholars such as Kamler and Thompson argue that identity formation has a key role to play in doctoral learning, particularly the process of thesis writing. This article builds on these insights to address other sites in which scholarly identity is performed within doctoral candidature. Drawing on actor-network theory, the authors examine the role…

  16. Sentiment Polarization and Balance among Users in Online Social Networks

    DEFF Research Database (Denmark)

    Hillmann, Robert; Trier, Matthias

    2012-01-01

    Communication within online social network applications enables users to express and share sentiments electronically. Existing studies examined the existence or distribution of sentiments in online communication at a general level or in small-observed groups. Our paper extends this research...... by analyzing sentiment exchange within social networks from an ego-network perspective. We draw from research on social influence and social attachment to develop theories of node polarization, balance effects and sentiment mirroring within communication dyads. Our empirical analysis covers a multitude...... of social networks in which the sentiment valence of all messages was determined. Subsequently we studied ego-networks of focal actors (ego) and their immediate contacts. Results support our theories and indicate that actors develop polarized sentiments towards individual peers but keep sentiment in balance...

  17. Using Social Network Theory to Influence the Development of State and Local Primary Prevention Capacity-Building Teams

    Science.gov (United States)

    Cook-Craig, Patricia G.

    2010-01-01

    This article examines the role that social network theory and social network analysis has played in assessing and developing effective primary prevention networks across a southeastern state. In 2004 the state began an effort to develop a strategic plan for the primary prevention of violence working with local communities across the state. The…

  18. Actors of the hydrogen sector in France

    International Nuclear Information System (INIS)

    2010-01-01

    This document proposes brief presentations (web site address, activities) of actors operating in the hydrogen sector in France. These actors are public actors who can be incentive or financing actors (ADEME, ANR) or research institutions (CNRS, CEA, university and engineering schools, IFP, INERIS, INRETS), private actors like industrial groups (Air Liquide, AREVA, GDF Suez, Total, PSA Peugeot Citroen, Renault, Saint-Gobain, SNECMA, ST Microelectronics, 3M, Veolia Environnement) or small companies (Alca Torda Applications, Axane, CETH2, Helion, MaHytec, N-GHY, PaxiTech, Sertronic, ULLIT). It also presents the HyPAC platform created by the AFH2 and ADEME), the AFH2 (the French Association for Hydrogen), and regional initiatives

  19. The Management of Political Actors in Institutions

    Directory of Open Access Journals (Sweden)

    Peter Odion Omoijiade

    2016-10-01

    Full Text Available The argument that the minimization of the dysfunctional consequences of organizational politics is no longer dependent on self-equilibrating mechanism remains valid. This inquiry is therefore framed with a view to establishing suitable strategies for managing political actors. There is a nexus between the diagnosis typology of political actors and the qualitative classes of political actors and their management strategies. In the management of mixed blessing, supportive, non-supportive and marginal political actors; collaborative, involvement, defensive and information strategies respectively were found suitable. This research is based on existing theoretical knowledge on organizational politics and stakeholders management. Data was collected from the literature by means of critical analysis and dialectic reflection on the emerging themes. The study will enhance capability in contexts where the scientific management of political actors is yet to be exemplified.

  20. Indications of marine bioinvasion from network theory. An analysis of the global cargo ship network

    Science.gov (United States)

    Kölzsch, A.; Blasius, B.

    2011-12-01

    The transport of huge amounts of small aquatic organisms in the ballast tanks and at the hull of large cargo ships leads to ever increasing rates of marine bioinvasion. In this study, we apply a network theoretic approach to examine the introduction of invasive species into new ports by global shipping. This is the first stage of the invasion process where it is still possible to intervene with regulating measures. We compile a selection of widely used and newly developed network properties and apply these to analyse the structure and spread characteristics of the directed and weighted global cargo ship network (GCSN). Our results reveal that the GCSN is highly efficient, shows small world characteristics and is positive assortative, indicating that quick spread of invasive organisms between ports is likely. The GCSN shows strong community structure and contains two large communities, the Atlantic and Pacific trading groups. Ports that appear as connector hubs and are of high centralities are the Suez and Panama Canal, Singapore and Shanghai. Furthermore, from robustness analyses and the network's percolation behaviour, we evaluate differences of onboard and in-port ballast water treatment, set them into context with previous studies and advise bioinvasion management strategies.

  1. Indications of marine bioinvasion from network theory. An analysis of the global cargo ship network

    NARCIS (Netherlands)

    Kölzsch, A.; Blasius, B.

    2011-01-01

    The transport of huge amounts of small aquatic organisms in the ballast tanks and at the hull of large cargo ships leads to ever increasing rates of marine bioinvasion. In this study, we apply a network theoretic approach to examine the introduction of invasive species into new ports by global

  2. Extending unified-theory-of-reinforcement neural networks to steady-state operant behavior.

    Science.gov (United States)

    Calvin, Olivia L; McDowell, J J

    2016-06-01

    The unified theory of reinforcement has been used to develop models of behavior over the last 20 years (Donahoe et al., 1993). Previous research has focused on the theory's concordance with the respondent behavior of humans and animals. In this experiment, neural networks were developed from the theory to extend the unified theory of reinforcement to operant behavior on single-alternative variable-interval schedules. This area of operant research was selected because previously developed neural networks could be applied to it without significant alteration. Previous research with humans and animals indicates that the pattern of their steady-state behavior is hyperbolic when plotted against the obtained rate of reinforcement (Herrnstein, 1970). A genetic algorithm was used in the first part of the experiment to determine parameter values for the neural networks, because values that were used in previous research did not result in a hyperbolic pattern of behavior. After finding these parameters, hyperbolic and other similar functions were fitted to the behavior produced by the neural networks. The form of the neural network's behavior was best described by an exponentiated hyperbola (McDowell, 1986; McLean and White, 1983; Wearden, 1981), which was derived from the generalized matching law (Baum, 1974). In post-hoc analyses the addition of a baseline rate of behavior significantly improved the fit of the exponentiated hyperbola and removed systematic residuals. The form of this function was consistent with human and animal behavior, but the estimated parameter values were not. Copyright © 2016 Elsevier B.V. All rights reserved.

  3. Optimal Placement of Actors in WSANs Based on Imposed Delay Constraints

    Directory of Open Access Journals (Sweden)

    Chunxi Yang

    2014-01-01

    Full Text Available Wireless Sensor and Actor Networks (WSANs refer to a group of sensors and actors linked by wireless medium to probe environment and perform specific actions. Such certain actions should always be taken before a deadline when an event of interest is detected. In order to provide such services, the whole monitor area is divided into several virtual areas and nodes in the same area form a cluster. Clustering of the WSANs is often pursued to give that each actor acts as a cluster-head. The number of actors is related to the size and the deployment of WSANs cluster. In this paper, we find a method to determine the accurate number of actors which enables them to receive data and take actions in an imposed time-delay. The k-MinTE and the k-MaxTE clustering algorithm are proposed to form the minimum and maximum size of cluster, respectively. In those clustering algorithms, actors are deployed in such a way that sensors could route data to actors within k hops. Then, clusters are arranged by the regular hexagon. At last, we evaluate the placement of actors and results show that our approach is effective.

  4. Unscrewing social media networks, twice

    DEFF Research Database (Denmark)

    Birkbak, Andreas

    2017-01-01

    Social media are often claimed to be an important new force in politics. One way to investigate such a claim is to follow an early call made in actor-network theory (ANT) to “unscrew” those entities that are assumed to be important and show how they are made up of heterogeneous networks of many...... different actors (Callon and Latour 1981). In this article I take steps towards unscrewing seven Facebook pages that were used to mobilize citizens for and against road pricing in Copenhagen in 2011-2012. But I encounter the difficulty that social media are already explicitly understood in Internet Studies...... that it can be combined with liberal notions of a singular public sphere (Somers 1995b; 1995a). In order to unscrew social media as a political force, I suggest that we need to work through both the assembling of social media networks and attend to corresponding reconstructions of liberal political narratives...

  5. Optimization of flow modeling in fractured media with discrete fracture network via percolation theory

    Science.gov (United States)

    Donado-Garzon, L. D.; Pardo, Y.

    2013-12-01

    Fractured media are very heterogeneous systems where occur complex physical and chemical processes to model. One of the possible approaches to conceptualize this type of massifs is the Discrete Fracture Network (DFN). Donado et al., modeled flow and transport in a granitic batholith based on this approach and found good fitting with hydraulic and tracer tests, but the computational cost was excessive due to a gigantic amount of elements to model. We present in this work a methodology based on percolation theory for reducing the number of elements and in consequence, to reduce the bandwidth of the conductance matrix and the execution time of each network. DFN poses as an excellent representation of all the set of fractures of the media, but not all the fractures of the media are part of the conductive network. Percolation theory is used to identify which nodes or fractures are not conductive, based on the occupation probability or percolation threshold. In a fractured system, connectivity determines the flow pattern in the fractured rock mass. This volume of fluid is driven through connection paths formed by the fractures, when the permeability of the rock is negligible compared to the fractures. In a population of distributed fractures, each of this that has no intersection with any connected fracture do not contribute to generate a flow field. This algorithm also permits us to erase these elements however they are water conducting and hence, refine even more the backbone of the network. We used 100 different generations of DFN that were optimized in this study using percolation theory. In each of the networks calibrate hydrodynamic parameters as hydraulic conductivity and specific storage coefficient, for each of the five families of fractures, yielding a total of 10 parameters to estimate, at each generation. Since the effects of the distribution of fault orientation changes the value of the percolation threshold, but not the universal laws of classical

  6. GTRF: a game theory approach for regulating node behavior in real-time wireless sensor networks.

    Science.gov (United States)

    Lin, Chi; Wu, Guowei; Pirozmand, Poria

    2015-06-04

    The selfish behaviors of nodes (or selfish nodes) cause packet loss, network congestion or even void regions in real-time wireless sensor networks, which greatly decrease the network performance. Previous methods have focused on detecting selfish nodes or avoiding selfish behavior, but little attention has been paid to regulating selfish behavior. In this paper, a Game Theory-based Real-time & Fault-tolerant (GTRF) routing protocol is proposed. GTRF is composed of two stages. In the first stage, a game theory model named VA is developed to regulate nodes' behaviors and meanwhile balance energy cost. In the second stage, a jumping transmission method is adopted, which ensures that real-time packets can be successfully delivered to the sink before a specific deadline. We prove that GTRF theoretically meets real-time requirements with low energy cost. Finally, extensive simulations are conducted to demonstrate the performance of our scheme. Simulation results show that GTRF not only balances the energy cost of the network, but also prolongs network lifetime.

  7. Functional network-based statistics in depression: Theory of mind subnetwork and importance of parietal region.

    Science.gov (United States)

    Lai, Chien-Han; Wu, Yu-Te; Hou, Yuh-Ming

    2017-08-01

    The functional network analysis of whole brain is an emerging field for research in depression. We initiated this study to investigate which subnetwork is significantly altered within the functional connectome in major depressive disorder (MDD). The study enrolled 52 first-episode medication-naïve patients with MDD and 40 controls for functional network analysis. All participants received the resting-state functional imaging using a 3-Tesla magnetic resonance scanner. After preprocessing, we calculated the connectivity matrix of functional connectivity in whole brain for each subject. The network-based statistics of connectome was used to perform group comparisons between patients and controls. The correlations between functional connectivity and clinical parameters were also performed. MDD patients had significant alterations in the network involving "theory of mind" regions, such as the left precentral gyrus, left angular gyrus, bilateral rolandic operculums and left inferior frontal gyrus. The center node of significant network was the left angular gyrus. No significant correlations of functional connectivity within the subnetwork and clinical parameters were noted. Functional connectivity of "theory of mind" subnetwork may be the core issue for pathophysiology in MDD. In addition, the center role of parietal region should be emphasized in future study. Copyright © 2017. Published by Elsevier B.V.

  8. Bombing alone: tracing the motivations and antecedent behaviors of lone-actor terrorists,.

    Science.gov (United States)

    Gill, Paul; Horgan, John; Deckert, Paige

    2014-03-01

    This article analyzes the sociodemographic network characteristics and antecedent behaviors of 119 lone-actor terrorists. This marks a departure from existing analyses by largely focusing upon behavioral aspects of each offender. This article also examines whether lone-actor terrorists differ based on their ideologies or network connectivity. The analysis leads to seven conclusions. There was no uniform profile identified. In the time leading up to most lone-actor terrorist events, other people generally knew about the offender's grievance, extremist ideology, views, and/or intent to engage in violence. A wide range of activities and experiences preceded lone actors' plots or events. Many but not all lone-actor terrorists were socially isolated. Lone-actor terrorists regularly engaged in a detectable and observable range of activities with a wider pressure group, social movement, or terrorist organization. Lone-actor terrorist events were rarely sudden and impulsive. There were distinguishable behavioral differences between subgroups. The implications for policy conclude this article. © 2013 American Academy of Forensic Sciences.

  9. The Construction of Higher Education Entrepreneur Services Network System a Research Based on Ecological Systems Theory

    Science.gov (United States)

    Xue, Jingxin

    The article aims to completely, systematically and objectively analyze the current situation of Entrepreneurship Education in China with Ecological Systems Theory. From this perspective, the author discusses the structure, function and its basic features of higher education entrepreneur services network system, and puts forward the opinion that every entrepreneurship organization in higher education institution does not limited to only one platform. Different functional supporting platforms should be combined closed through composite functional organization to form an integrated network system, in which each unit would impels others' development.

  10. Hardware implementation of an adaptive resonance theory (ART) neural network using compensated operational amplifiers

    Science.gov (United States)

    Ho, Ching S.; Liou, Juin J.; Georgiopoulos, Michael; Christodoulou, Christos G.

    1994-03-01

    This paper presents an analog circuit design and implementation for an adaptive resonance theory neural network architecture called the augmented ART1 neural network (AART1-NN). Practical monolithic operational amplifiers (Op-Amps) LM741 and LM318 are selected to implement the circuit, and a simple compensation scheme is developed to adjust the Op-Amp electrical characteristics to meet the design requirement. A 7-node prototype circuit has been designed and verified using the Pspice circuit simulator run on a Sun workstation. Results simulated from the AART1-NN circuit using the LM741, LM318, and ideal Op-Amps are presented and compared.

  11. Hacia una redefinición de los movimientos sociales: macro-actores proxémicos

    Directory of Open Access Journals (Sweden)

    Mendiola, Ignacio

    2003-11-01

    Full Text Available The aim of this paper is to propose a conceptualization of social movements that is not limited to the set of theories developed in the academic scope of new social movements; on the contrary, a different theoretical scenery will be suggested in order to throw a new analytic gaze on the social practices reproduced by the, so called, new social movements. This gaze will be built on three distinct but interrelated premises. Firstly, it will be stressed the paradoxical dimension of identitarian practices and, consequently, the impossibility to define a social reality according to a single dimension. Secondly, paradoxical dimension will be taken to the scope of social movements in order to propose a definition of social movements that takes into account a constitutive paradox where a proxemic sociality and actor-network theory are put in relation. Lastly, the unfolding of such paradox is analyzed looking at its ironic style.

  12. Adversarial Advantage Actor-Critic Model for Task-Completion Dialogue Policy Learning

    OpenAIRE

    Peng, Baolin; Li, Xiujun; Gao, Jianfeng; Liu, Jingjing; Chen, Yun-Nung; Wong, Kam-Fai

    2017-01-01

    This paper presents a new method --- adversarial advantage actor-critic (Adversarial A2C), which significantly improves the efficiency of dialogue policy learning in task-completion dialogue systems. Inspired by generative adversarial networks (GAN), we train a discriminator to differentiate responses/actions generated by dialogue agents from responses/actions by experts. Then, we incorporate the discriminator as another critic into the advantage actor-critic (A2C) framework, to encourage the...

  13. A study on the critical factors which influence habitual entrepreneurs' success in networking from the perspective of social captial theory

    OpenAIRE

    Li, SiQi

    2012-01-01

    The aim of the research is to provide an insight on the critical factors which influence habitual entrepreneurs’ success in networking through which effective networking strategies may lead to increased business performance. The perspective of explaining the factors adopts social capital theory and social dimensions of entrepreneurs’ network. The key findings suggest that social capital is in a form of non-linear pattern that the interactions are complex. Network configuration influences effe...

  14. Analysis of Online Social Networks to Understand Information Sharing Behaviors Through Social Cognitive Theory.

    Science.gov (United States)

    Yoon, Hong-Jun; Tourassi, Georgia

    2014-05-01

    Analyzing the contents of online social networks is an effective process for monitoring and understanding peoples' behaviors. Since the nature of conversation and information propagation is similar to traditional conversation and learning, one of the popular socio-cognitive methods, social cognitive theory was applied to online social networks to. Two major news topics about colon cancer were chosen to monitor traffic of Twitter messages. The activity of "leaders" on the issue (i.e., news companies or people will prior Twitter activity on topics related to colon cancer) was monitored. In addition, the activity of "followers", people who never discussed the topics before, but replied to the discussions was also monitored. Topics that produce tangible benefits such as positive outcomes from appropriate preventive actions received dramatically more attention and online social media traffic. Such characteristics can be explained with social cognitive theory and thus present opportunities for effective health campaigns.

  15. Actor Diversity and Interactions in the Development of Banana Hybrid Varieties in Uganda: Implications for Technology Uptake

    Science.gov (United States)

    Sanya, Losira Nasirumbi; Sseguya, Haroon; Kyazze, Florence Birungi; Baguma, Yona; Kibwika, Paul

    2018-01-01

    Purpose: We examine the nature of networks through which new hybrid banana varieties (HBVs) in Uganda are developed, and how different actors engage in the technology development process. Design/methodology/approach: We collected the data through 20 key informant interviews and 5 focus group discussions with actors involved in the process. We…

  16. Langevin-elasticity-theory-based description of the tensile properties of double network rubbers

    Czech Academy of Sciences Publication Activity Database

    Meissner, Bohumil; Matějka, Libor

    2003-01-01

    Roč. 44, č. 16 (2003), s. 4611-4617 ISSN 0032-3861 R&D Projects: GA ČR GA104/00/1311; GA AV ČR IAA4050008 Institutional research plan: CEZ:AV0Z4050913 Keywords : theory of rubber elasticity * double network rubbers * experimental testing Subject RIV: CD - Macromolecular Chemistry Impact factor: 2.340, year: 2003

  17. Altered Brain Network in Amyotrophic Lateral Sclerosis: A Resting Graph Theory-Based Network Study at Voxel-Wise Level.

    Science.gov (United States)

    Zhou, Chaoyang; Hu, Xiaofei; Hu, Jun; Liang, Minglong; Yin, Xuntao; Chen, Lin; Zhang, Jiuquan; Wang, Jian

    2016-01-01

    Amyotrophic lateral sclerosis (ALS) is a rare degenerative disorder characterized by loss of upper and lower motor neurons. Neuroimaging has provided noticeable evidence that ALS is a complex disease, and shown that anatomical and functional lesions extend beyond precentral cortices and corticospinal tracts, to include the corpus callosum; frontal, sensory, and premotor cortices; thalamus; and midbrain. The aim of this study is to investigate graph theory-based functional network abnormalities at voxel-wise level in ALS patients on a whole brain scale. Forty-three ALS patients and 44 age- and sex-matched healthy volunteers were enrolled. The voxel-wise network degree centrality (DC), a commonly employed graph-based measure of network organization, was used to characterize the alteration of whole brain functional network. Compared with the controls, the ALS patients showed significant increase of DC in the left cerebellum posterior lobes, bilateral cerebellum crus, bilateral occipital poles, right orbital frontal lobe, and bilateral prefrontal lobes; significant decrease of DC in the bilateral primary motor cortex, bilateral sensory motor region, right prefrontal lobe, left bilateral precuneus, bilateral lateral temporal lobes, left cingulate cortex, and bilateral visual processing cortex. The DC's z-scores of right inferior occipital gyrus were significant negative correlated with the ALSFRS-r scores. Our findings confirm that the regions with abnormal network DC in ALS patients were located in multiple brain regions including primary motor, somatosensory and extra-motor areas, supporting the concept that ALS is a multisystem disorder. Specifically, our study found that DC in the visual areas was altered and ALS patients with higher DC in right inferior occipital gyrus have more severity of disease. The result demonstrated that the altered DC value in this region can probably be used to assess severity of ALS.

  18. Altered brain network in Amyotrophic Lateral Sclerosis: a resting graph theory-based network study at voxel-wise level

    Directory of Open Access Journals (Sweden)

    Chaoyang eZhou

    2016-05-01

    Full Text Available Amyotrophic lateral sclerosis (ALS is a rare degenerative disorder characterized by loss of upper and lower motor neurons. Neuroimaging has provided noticeable evidence that ALS is a complex disease, and shown that anatomical and functional lesions extend beyond precentral cortices and corticospinal tracts, to include the corpus callosum; frontal, sensory, and premotor cortices; thalamus; and midbrain. The aim of this study is to investigate graph theory-based functional network abnormalities at voxel-wise level in ALS patients on a whole brain scale. Forty-three ALS patients and 44 age- and sex- matched healthy volunteers were enrolled. The voxel-wise network degree centrality (DC, a commonly employed graph-based measure of network organization, was used to characterize the alteration of whole brain functional network. Compared with the controls, the ALS patients showed significant increase of DC in the left cerebellum posterior lobes, bilateral cerebellum crus, bilateral occipital poles, right orbital frontal lobe and bilateral prefrontal lobes; significant decrease of DC in the bilateral primary motor cortex, bilateral sensory motor region, right prefrontal lobe, left bilateral precuneus, bilateral lateral temporal lobes, left cingulate cortex, and bilateral visual processing cortex. The DC’s z-scores of right inferior occipital gyrus were significant negative correlated with the ALSFRS-r scores. Our findings confirm that the regions with abnormal network DC in ALS patients were located in multiple brain regions including primary motor, somatosensory and extra-motor areas, supporting the concept that ALS is a multisystem disorder. Specifically, our study found that DC in the visual areas was altered and ALS patients with higher DC in right inferior occipital gyrus have more severity of disease. The result demonstrated that the altered DC value in this region can probably be used to assess severity of ALS.

  19. Driving the brain towards creativity and intelligence: A network control theory analysis.

    Science.gov (United States)

    Kenett, Yoed N; Medaglia, John D; Beaty, Roger E; Chen, Qunlin; Betzel, Richard F; Thompson-Schill, Sharon L; Qiu, Jiang

    2018-01-04

    High-level cognitive constructs, such as creativity and intelligence, entail complex and multiple processes, including cognitive control processes. Recent neurocognitive research on these constructs highlight the importance of dynamic interaction across neural network systems and the role of cognitive control processes in guiding such a dynamic interaction. How can we quantitatively examine the extent and ways in which cognitive control contributes to creativity and intelligence? To address this question, we apply a computational network control theory (NCT) approach to structural brain imaging data acquired via diffusion tensor imaging in a large sample of participants, to examine how NCT relates to individual differences in distinct measures of creative ability and intelligence. Recent application of this theory at the neural level is built on a model of brain dynamics, which mathematically models patterns of inter-region activity propagated along the structure of an underlying network. The strength of this approach is its ability to characterize the potential role of each brain region in regulating whole-brain network function based on its anatomical fingerprint and a simplified model of node dynamics. We find that intelligence is related to the ability to "drive" the brain system into easy to reach neural states by the right inferior parietal lobe and lower integration abilities in the left retrosplenial cortex. We also find that creativity is related to the ability to "drive" the brain system into difficult to reach states by the right dorsolateral prefrontal cortex (inferior frontal junction) and higher integration abilities in sensorimotor areas. Furthermore, we found that different facets of creativity-fluency, flexibility, and originality-relate to generally similar but not identical network controllability processes. We relate our findings to general theories on intelligence and creativity. Copyright © 2018 Elsevier Ltd. All rights reserved.

  20. [Reliability theory based on quality risk network analysis for Chinese medicine injection].

    Science.gov (United States)

    Li, Zheng; Kang, Li-Yuan; Fan, Xiao-Hui

    2014-08-01

    A new risk analysis method based upon reliability theory was introduced in this paper for the quality risk management of Chinese medicine injection manufacturing plants. The risk events including both cause and effect ones were derived in the framework as nodes with a Bayesian network analysis approach. It thus transforms the risk analysis results from failure mode and effect analysis (FMEA) into a Bayesian network platform. With its structure and parameters determined, the network can be used to evaluate the system reliability quantitatively with probabilistic analytical appraoches. Using network analysis tools such as GeNie and AgenaRisk, we are able to find the nodes that are most critical to influence the system reliability. The importance of each node to the system can be quantitatively evaluated by calculating the effect of the node on the overall risk, and minimization plan can be determined accordingly to reduce their influences and improve the system reliability. Using the Shengmai injection manufacturing plant of SZYY Ltd as a user case, we analyzed the quality risk with both static FMEA analysis and dynamic Bayesian Network analysis. The potential risk factors for the quality of Shengmai injection manufacturing were identified with the network analysis platform. Quality assurance actions were further defined to reduce the risk and improve the product quality.

  1. A Game Theory Based Congestion Control Protocol for Wireless Personal Area Networks

    Directory of Open Access Journals (Sweden)

    Chuang Ma

    2016-01-01

    Full Text Available In wireless sensor networks (WSNs, the presence of congestion increases the ratio of packet loss and energy consumption and reduces the network throughput. Particularly, this situation will be more complex in Internet of Things (IoT environment, which is composed of thousands of heterogeneous nodes. RPL is an IPv6 routing protocol in low power and lossy networks standardized by IETF. However, the RPL can induce problems under network congestion, such as frequently parent changing and throughput degradation. In this paper, we address the congestion problem between parent nodes and child nodes in RPL-enabled networks, which typically consist of low power and resource constraint devices. To mitigate the effect of network congestion, we design a parent-change procedure by game theory strategy, by which the child nodes can change next hop neighbors toward the sink. Comparing to the ContikiRPL implementation, the simulation results show that our protocol can achieve more than two times improvement in throughput and reduce packet loss rate with less increasing of average hop count.

  2. Mean-field Theory for Some Bus Transport Networks with Random Overlapping Clique Structure

    International Nuclear Information System (INIS)

    Yang Xuhua; Sun Bao; Wang Bo; Sun Youxian

    2010-01-01

    Transport networks, such as railway networks and airport networks, are a kind of random network with complex topology. Recently, more and more scholars paid attention to various kinds of transport networks and try to explore their inherent characteristics. Here we study the exponential properties of a recently introduced Bus Transport Networks (BTNs) evolution model with random overlapping clique structure, which gives a possible explanation for the observed exponential distribution of the connectivities of some BTNs of three major cities in China. Applying mean-field theory, we analyze the BTNs model and prove that this model has the character of exponential distribution of the connectivities, and develop a method to predict the growth dynamics of the individual vertices, and use this to calculate analytically the connectivity distribution and the exponents. By comparing mean-field based theoretic results with the statistical data of real BTNs, we observe that, as a whole, both of their data show similar character of exponential distribution of the connectivities, and their exponents have same order of magnitude, which show the availability of the analytical result of this paper. (general)

  3. Random matrix theory for analyzing the brain functional network in attention deficit hyperactivity disorder

    Science.gov (United States)

    Wang, Rong; Wang, Li; Yang, Yong; Li, Jiajia; Wu, Ying; Lin, Pan

    2016-11-01

    Attention deficit hyperactivity disorder (ADHD) is the most common childhood neuropsychiatric disorder and affects approximately 6 -7 % of children worldwide. Here, we investigate the statistical properties of undirected and directed brain functional networks in ADHD patients based on random matrix theory (RMT), in which the undirected functional connectivity is constructed based on correlation coefficient and the directed functional connectivity is measured based on cross-correlation coefficient and mutual information. We first analyze the functional connectivity and the eigenvalues of the brain functional network. We find that ADHD patients have increased undirected functional connectivity, reflecting a higher degree of linear dependence between regions, and increased directed functional connectivity, indicating stronger causality and more transmission of information among brain regions. More importantly, we explore the randomness of the undirected and directed functional networks using RMT. We find that for ADHD patients, the undirected functional network is more orderly than that for normal subjects, which indicates an abnormal increase in undirected functional connectivity. In addition, we find that the directed functional networks are more random, which reveals greater disorder in causality and more chaotic information flow among brain regions in ADHD patients. Our results not only further confirm the efficacy of RMT in characterizing the intrinsic properties of brain functional networks but also provide insights into the possibilities RMT offers for improving clinical diagnoses and treatment evaluations for ADHD patients.

  4. Assessing and accounting for time heterogeneity in stochastic actor oriented models

    NARCIS (Netherlands)

    Lospinoso, Joshua A.; Schweinberger, Michael; Snijders, Tom A. B.; Ripley, Ruth M.

    This paper explores time heterogeneity in stochastic actor oriented models (SAOM) proposed by Snijders (Sociological methodology. Blackwell, Boston, pp 361-395, 2001) which are meant to study the evolution of networks. SAOMs model social networks as directed graphs with nodes representing people,

  5. Understanding and Using the Controller Area Network Communication Protocol Theory and Practice

    CERN Document Server

    Di Natale, Marco; Giusto, Paolo; Ghosal, Arkadeb

    2012-01-01

    This is the first book to offer a hands-on guide to designing, analyzing and debugging a communication infrastructure based on the Controller Area Network (CAN) bus.  Although the CAN bus standard is well established and currently used in most automotive systems, as well as avionics, medical systems and other devices, its features are not fully understood by most developers, who tend to misuse the network. This results in lost opportunities for better efficiency and performance.   This book offers a comprehensive range of architectural solutions and domains of analysis. It also provides formal models and analytical results, with thorough discussion of their applicability, so that it serves as an invaluable reference for researchers and students, as well as practicing engineers.    Offers the first comprehensive guide to bridging the gap between theory and implementation of the widely accepted Controller Area Network (CAN) bus; Provides examples and best practices for design of communication systems, as w...

  6. Locally excitatory, globally inhibitory oscillator networks: theory and application to scene segmentation

    Science.gov (United States)

    Wang, DeLiang; Terman, David

    1995-01-01

    A novel class of locally excitatory, globally inhibitory oscillator networks (LEGION) is proposed and investigated analytically and by computer simulation. The model of each oscillator corresponds to a standard relaxation oscillator with two time scales. The network exhibits a mechanism of selective gating, whereby an oscillator jumping up to its active phase rapidly recruits the oscillators stimulated by the same pattern, while preventing other oscillators from jumping up. We show analytically that with the selective gating mechanism the network rapidly achieves both synchronization within blocks of oscillators that are stimulated by connected regions and desynchronization between different blocks. Computer simulations demonstrate LEGION's promising ability for segmenting multiple input patterns in real time. This model lays a physical foundation for the oscillatory correlation theory of feature binding, and may provide an effective computational framework for scene segmentation and figure/ground segregation.

  7. A Network Neuroscience of Human Learning: Potential to Inform Quantitative Theories of Brain and Behavior.

    Science.gov (United States)

    Bassett, Danielle S; Mattar, Marcelo G

    2017-04-01

    Humans adapt their behavior to their external environment in a process often facilitated by learning. Efforts to describe learning empirically can be complemented by quantitative theories that map changes in neurophysiology to changes in behavior. In this review we highlight recent advances in network science that offer a sets of tools and a general perspective that may be particularly useful in understanding types of learning that are supported by distributed neural circuits. We describe recent applications of these tools to neuroimaging data that provide unique insights into adaptive neural processes, the attainment of knowledge, and the acquisition of new skills, forming a network neuroscience of human learning. While promising, the tools have yet to be linked to the well-formulated models of behavior that are commonly utilized in cognitive psychology. We argue that continued progress will require the explicit marriage of network approaches to neuroimaging data and quantitative models of behavior. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Linking experiment and theory for three-dimensional networked binary metal nanoparticle–triblock terpolymer superstructures

    KAUST Repository

    Li, Zihui

    2014-02-21

    © 2014 Macmillan Publishers Limited. Controlling superstructure of binary nanoparticle mixtures in three dimensions from self-assembly opens enormous opportunities for the design of materials with unique properties. Here we report on how the intimate coupling of synthesis, in-depth electron tomographic characterization and theory enables exquisite control of superstructure in highly ordered porous three-dimensional continuous networks from single and binary mixtures of metal nanoparticles with a triblock terpolymer. Poly(isoprene-block-styrene-block-(N,N-dimethylamino)ethyl methacrylate) is synthesized and used as structure-directing agent for ligand-stabilized platinum and gold nanoparticles. Quantitative analysis provides insights into short-and long-range nanoparticle-nanoparticle correlations, and local and global contributions to structural chirality in the networks. Results provide synthesis criteria for next-generation mesoporous network superstructures from binary nanoparticle mixtures for potential applications in areas including catalysis.

  9. An Interview with Tony David Sampson: Author of Virality: Contagion Theory in the Age of Networks

    Directory of Open Access Journals (Sweden)

    Tara Robbins Fee

    2016-12-01

    Full Text Available Tony D. Sampson is Reader in Digital Culture and Communication in the School of Arts and Digital Industries (ADI at the University of East London, where he directs the EmotionUX lab, supervising research on the cognitive, emotional, and affective aspects of user experience. In 2013, he co-founded Club Critical Theory, an organization dedicated to the application of critical theory in everyday life in Southend-on-Sea, Essex. Tony is the author of Virality: Contagion Theory in the Age of Networks and The Assemblage Brain: Sense Making in Neuroculture, both from the University of Minnesota Press. He blogs at viralcontagion.wordpress.com. The editors of this special NANO issue are delighted to have the opportunity to talk with Tony about how his work touches on issues of imitation and contagion—a loaded term unpacked within his 2012 book.

  10. Material Matters for Learning in Virtual Networks: A Case Study of a Professional Learning Programme Hosted in a Google+ Online Community

    Science.gov (United States)

    Ackland, Aileen; Swinney, Ann

    2015-01-01

    In this paper, we draw on Actor-Network Theories (ANT) to explore how material components functioned to create gateways and barriers to a virtual learning network in the context of a professional development module in higher education. Students were practitioners engaged in family learning in different professional roles and contexts. The data…

  11. Functional neural network analysis in frontotemporal dementia and Alzheimer's disease using EEG and graph theory

    Directory of Open Access Journals (Sweden)

    van der Flier Wiesje M

    2009-08-01

    Full Text Available Abstract Background Although a large body of knowledge about both brain structure and function has been gathered over the last decades, we still have a poor understanding of their exact relationship. Graph theory provides a method to study the relation between network structure and function, and its application to neuroscientific data is an emerging research field. We investigated topological changes in large-scale functional brain networks in patients with Alzheimer's disease (AD and frontotemporal lobar degeneration (FTLD by means of graph theoretical analysis of resting-state EEG recordings. EEGs of 20 patients with mild to moderate AD, 15 FTLD patients, and 23 non-demented individuals were recorded in an eyes-closed resting-state. The synchronization likelihood (SL, a measure of functional connectivity, was calculated for each sensor pair in 0.5–4 Hz, 4–8 Hz, 8–10 Hz, 10–13 Hz, 13–30 Hz and 30–45 Hz frequency bands. The resulting connectivity matrices were converted to unweighted graphs, whose structure was characterized with several measures: mean clustering coefficient (local connectivity, characteristic path length (global connectivity and degree correlation (network 'assortativity'. All results were normalized for network size and compared with random control networks. Results In AD, the clustering coefficient decreased in the lower alpha and beta bands (p Conclusion With decreasing local and global connectivity parameters, the large-scale functional brain network organization in AD deviates from the optimal 'small-world' network structure towards a more 'random' type. This is associated with less efficient information exchange between brain areas, supporting the disconnection hypothesis of AD. Surprisingly, FTLD patients show changes in the opposite direction, towards a (perhaps excessively more 'ordered' network structure, possibly reflecting a different underlying pathophysiological process.

  12. Visibility graph analysis on quarterly macroeconomic series of China based on complex network theory

    Science.gov (United States)

    Wang, Na; Li, Dong; Wang, Qiwen

    2012-12-01

    The visibility graph approach and complex network theory provide a new insight into time series analysis. The inheritance of the visibility graph from the original time series was further explored in the paper. We found that degree distributions of visibility graphs extracted from Pseudo Brownian Motion series obtained by the Frequency Domain algorithm exhibit exponential behaviors, in which the exponential exponent is a binomial function of the Hurst index inherited in the time series. Our simulations presented that the quantitative relations between the Hurst indexes and the exponents of degree distribution function are different for different series and the visibility graph inherits some important features of the original time series. Further, we convert some quarterly macroeconomic series including the growth rates of value-added of three industry series and the growth rates of Gross Domestic Product series of China to graphs by the visibility algorithm and explore the topological properties of graphs associated from the four macroeconomic series, namely, the degree distribution and correlations, the clustering coefficient, the average path length, and community structure. Based on complex network analysis we find degree distributions of associated networks from the growth rates of value-added of three industry series are almost exponential and the degree distributions of associated networks from the growth rates of GDP series are scale free. We also discussed the assortativity and disassortativity of the four associated networks as they are related to the evolutionary process of the original macroeconomic series. All the constructed networks have “small-world” features. The community structures of associated networks suggest dynamic changes of the original macroeconomic series. We also detected the relationship among government policy changes, community structures of associated networks and macroeconomic dynamics. We find great influences of government

  13. Understanding Regional Actors: A Case Study

    National Research Council Canada - National Science Library

    Harden, James

    2002-01-01

    .... It is possible the estimation process could improve if greater attention was given to the interests, challenges, and opportunities of the regional actors involved, rather than concentrating on U.S. interests...

  14. Applying network theory to animal movements to identify properties of landscape space use.

    Science.gov (United States)

    Bastille-Rousseau, Guillaume; Douglas-Hamilton, Iain; Blake, Stephen; Northrup, Joseph M; Wittemyer, George

    2018-04-01

    Network (graph) theory is a popular analytical framework to characterize the structure and dynamics among discrete objects and is particularly effective at identifying critical hubs and patterns of connectivity. The identification of such attributes is a fundamental objective of animal movement research, yet network theory has rarely been applied directly to animal relocation data. We develop an approach that allows the analysis of movement data using network theory by defining occupied pixels as nodes and connection among these pixels as edges. We first quantify node-level (local) metrics and graph-level (system) metrics on simulated movement trajectories to assess the ability of these metrics to pull out known properties in movement paths. We then apply our framework to empirical data from African elephants (Loxodonta africana), giant Galapagos tortoises (Chelonoidis spp.), and mule deer (Odocoileous hemionus). Our results indicate that certain node-level metrics, namely degree, weight, and betweenness, perform well in capturing local patterns of space use, such as the definition of core areas and paths used for inter-patch movement. These metrics were generally applicable across data sets, indicating their robustness to assumptions structuring analysis or strategies of movement. Other metrics capture local patterns effectively, but were sensitive to specified graph properties, indicating case specific applications. Our analysis indicates that graph-level metrics are unlikely to outperform other approaches for the categorization of general movement strategies (central place foraging, migration, nomadism). By identifying critical nodes, our approach provides a robust quantitative framework to identify local properties of space use that can be used to evaluate the effect of the loss of specific nodes on range wide connectivity. Our network approach is intuitive, and can be implemented across imperfectly sampled or large-scale data sets efficiently, providing a

  15. Network Theory Integrated Life Cycle Assessment for an Electric Power System

    Directory of Open Access Journals (Sweden)

    Heetae Kim

    2015-08-01

    Full Text Available In this study, we allocate Greenhouse gas (GHG emissions of electricity transmission to the consumers. As an allocation basis, we introduce energy distance. Energy distance takes the transmission load on the electricity energy system into account in addition to the amount of electricity consumption. As a case study, we estimate regional GHG emissions of electricity transmission loss in Chile. Life cycle assessment (LCA is used to estimate the total GHG emissions of the Chilean electric power system. The regional GHG emission of transmission loss is calculated from the total GHG emissions. We construct the network model of Chilean electric power grid as an undirected network with 466 nodes and 543 edges holding the topology of the power grid based on the statistical record. We analyze the total annual GHG emissions of the Chilean electricity energy system as 23.07 Mt CO2-eq. and 1.61 Mt CO2-eq. for the transmission loss, respectively. The total energy distance for the electricity transmission accounts for 12,842.10 TWh km based on network analysis. We argue that when the GHG emission of electricity transmission loss is estimated, the electricity transmission load should be separately considered. We propose network theory as a useful complement to LCA analysis for the complex allocation. Energy distance is especially useful on a very large-scale electric power grid such as an intercontinental transmission network.

  16. The Psychological Self as Actor, Agent, and Author.

    Science.gov (United States)

    McAdams, Dan P

    2013-05-01

    The psychological self may be construed as a reflexive arrangement of the subjective "I" and the constructed "Me," evolving and expanding over the human life course. The psychological self begins life as a social actor, construed in terms of performance traits and social roles. By the end of childhood, the self has become a motivated agent, too, as personal goals, motives, values, and envisioned projects for the future become central features of how the I conceives of the Me. A third layer of selfhood begins to form in the adolescent and emerging adulthood years, when the self as autobiographical author aims to construct a story of the Me, to provide adult life with broad purpose and a dynamic sense of temporal continuity. An integrative theory that envisions the psychological self as a developing I-Me configuration of actor, agent, and author helps to synthesize a wide range of conceptions and findings on the self from social, personality, cognitive, cultural, and developmental psychology and from sociology and other social sciences. The actor-agent-author framework also sheds new light on studies of self-regulation, self-esteem, self-continuity, and the relationship between self and culture. © The Author(s) 2013.

  17. Comparing brain networks of different size and connectivity density using graph theory.

    Directory of Open Access Journals (Sweden)

    Bernadette C M van Wijk

    Full Text Available Graph theory is a valuable framework to study the organization of functional and anatomical connections in the brain. Its use for comparing network topologies, however, is not without difficulties. Graph measures may be influenced by the number of nodes (N and the average degree (k of the network. The explicit form of that influence depends on the type of network topology, which is usually unknown for experimental data. Direct comparisons of graph measures between empirical networks with different N and/or k can therefore yield spurious results. We list benefits and pitfalls of various approaches that intend to overcome these difficulties. We discuss the initial graph definition of unweighted graphs via fixed thresholds, average degrees or edge densities, and the use of weighted graphs. For instance, choosing a threshold to fix N and k does eliminate size and density effects but may lead to modifications of the network by enforcing (ignoring non-significant (significant connections. Opposed to fixing N and k, graph measures are often normalized via random surrogates but, in fact, this may even increase the sensitivity to differences in N and k for the commonly used clustering coefficient and small-world index. To avoid such a bias we tried to estimate the N,k-dependence for empirical networks, which can serve to correct for size effects, if successful. We also add a number of methods used in social sciences that build on statistics of local network structures including exponential random graph models and motif counting. We show that none of the here-investigated methods allows for a reliable and fully unbiased comparison, but some perform better than others.

  18. An efficient approach for electric load forecasting using distributed ART (adaptive resonance theory) and HS-ARTMAP (Hyper-spherical ARTMAP network) neural network

    International Nuclear Information System (INIS)

    Cai, Yuan; Wang, Jian-zhou; Tang, Yun; Yang, Yu-chen

    2011-01-01

    This paper presents a neural network based on adaptive resonance theory, named distributed ART (adaptive resonance theory) and HS-ARTMAP (Hyper-spherical ARTMAP network), applied to the electric load forecasting problem. The distributed ART combines the stable fast learning capabilities of winner-take-all ART systems with the noise tolerance and code compression capabilities of multi-layer perceptions. The HS-ARTMAP, a hybrid of an RBF (Radial Basis Function)-network-like module which uses hyper-sphere basis function substitute the Gaussian basis function and an ART-like module, performs incremental learning capabilities in function approximation problem. The HS-ARTMAP only receives the compressed distributed coding processed by distributed ART to deal with the proliferation problem which ARTMAP (adaptive resonance theory map) architecture often encounters and still performs well in electric load forecasting. To demonstrate the performance of the methodology, data from New South Wales and Victoria in Australia are illustrated. Results show that the developed method is much better than the traditional BP and single HS-ARTMAP neural network. -- Research highlights: → The processing of the presented network is based on compressed distributed data. It's an innovation among the adaptive resonance theory architecture. → The presented network decreases the proliferation the Fuzzy ARTMAP architectures usually encounter. → The network on-line forecasts electrical load accurately, stably. → Both one-period and multi-period load forecasting are executed using data of different cities.

  19. Can new institutional theory contribute to the understanding of the actors` behaviour in connection with energy savings? A theoretical discussion; Kan nyinstitutionel teori bidrage til forstaaelsen af aktoerernes adfaerd i forbindelse med energibesparelser? - En teoretisk diskussion

    Energy Technology Data Exchange (ETDEWEB)

    Holm Pedersen, L.

    1997-09-01

    The neoclassical economy predicts that energy savings which can pay will be undertaken, and that energy savings which do not pay will not be carried through. However, the empirical investigations suggest that situations where energy savings are not immediately undertaken also exist, although they are profitable, and that there are situations where energy savings are carried through, although they are not profitable. In these situations the neoclassical economy seems to lack explanatory power. In the development of a theoretical framework for the study of energy savings it is investigated whether the new institutional theory can supplement the explanatory power of the neoclassical economy. The theory is to some extent a renewal of the social sciences, which takes into consideration that decision-making is often founded on imperfect information, and that people are affected by their social and institutional environment. The new institutional theory can supplement and support the neoclassical economy in providing a theoretical framework for the analysis of energy savings. However, it is outside the realm of the present report to make an empirical investigation of how often the situation seems to be that energy savings which pay are not carried through, or that energy savings are undertaken even though they do not pay in the pure economic sense. The situation might also be that energy savings mainly are undertaken when it is both profitable and given a special significance in the households or companies. However, it will take further empirical investigations to assess the explanatory power of the two theoretical perspectives. In this study it has only been possible to establish a theoretical framework for such investigations. (LN) 92 refs.

  20. Inference and Analysis of Population Structure Using Genetic Data and Network Theory.

    Science.gov (United States)

    Greenbaum, Gili; Templeton, Alan R; Bar-David, Shirli

    2016-04-01

    Clustering individuals to subpopulations based on genetic data has become commonplace in many genetic studies. Inference about population structure is most often done by applying model-based approaches, aided by visualization using distance-based approaches such as multidimensional scaling. While existing distance-based approaches suffer from a lack of statistical rigor, model-based approaches entail assumptions of prior conditions such as that the subpopulations are at Hardy-Weinberg equilibria. Here we present a distance-based approach for inference about population structure using genetic data by defining population structure using network theory terminology and methods. A network is constructed from a pairwise genetic-similarity matrix of all sampled individuals. The community partition, a partition of a network to dense subgraphs, is equated with population structure, a partition of the population to genetically related groups. Community-detection algorithms are used to partition the network into communities, interpreted as a partition of the population to subpopulations. The statistical significance of the structure can be estimated by using permutation tests to evaluate the significance of the partition's modularity, a network theory measure indicating the quality of community partitions. To further characterize population structure, a new measure of the strength of association (SA) for an individual to its assigned community is presented. The strength of association distribution (SAD) of the communities is analyzed to provide additional population structure characteristics, such as the relative amount of gene flow experienced by the different subpopulations and identification of hybrid individuals. Human genetic data and simulations are used to demonstrate the applicability of the analyses. The approach presented here provides a novel, computationally efficient model-free method for inference about population structure that does not entail assumption of

  1. Practice of Connectivism As Learning Theory: Enhancing Learning Process Through Social Networking Site (Facebook

    Directory of Open Access Journals (Sweden)

    Fahriye Altınay Aksal

    2013-12-01

    Full Text Available The impact of the digital age within learning and social interaction has been growing rapidly. The realm of digital age and computer mediated communication requires reconsidering instruction based on collaborative interactive learning process and socio-contextual experience for learning. Social networking sites such as facebook can help create group space for digital dialogue to inform, question and challenge within a frame of connectivism as learning theory within the digital age. The aim of this study is to elaborate the practice of connectivism as learning theory in terms of internship course. Facebook group space provided social learning platform for dialogue and negotiation beside the classroom learning and teaching process in this study. The 35 internship students provided self-reports within a frame of this qualitative research. This showed how principles of theory practiced and how this theory and facebook group space contribute learning, selfleadership, decision making and reflection skills. As the research reflects a practice of new theory based on action research, learning is not individualistic attempt in the digital age as regards the debate on learning in digital age within a frame of connectivism

  2. Learning network theory : its contribution to our understanding of work-based learning projects and learning climate

    OpenAIRE

    Poell, R.F.; Moorsel, M.A.A.H. van

    1996-01-01

    This paper discusses the relevance of Van der Krogt's learning network theory (1995) for our understanding of the concepts of work-related learning projects and learning climate in organisations. The main assumptions of the learning network theory are presented and transferred to the level of learning groups in organisations. Four theoretical types of learning projects are distinguished. Four different approaches to the learning climate of work groups are compared to the approach offered by t...

  3. ACTOR`S EXPRESSIVENESS: PHYSICAL ACTION AS A LANGUAGE OF ARCHETYPES

    Directory of Open Access Journals (Sweden)

    CATEREVA IRINA

    2016-06-01

    Full Text Available Physical activity is the main element of the nonverbal expressiveness of the actor. Th e nonpsychological theatre of Europe in the second half of the 20th century was looking for the actor`s possibility of physical action for revealing the archetypal image of the character. Expressing the meanings similar among themselves in diff erent Nations, they connect the actors and spectators at the level of feelings, of the subconscious. Destroying the barriers in people’s minds which divides them into Europeans and Asians, or French and Germans, they are understandable to any audience regardless of their cultural or linguistic affiliation.

  4. Differential recruitment of theory of mind brain network across three tasks: An independent component analysis.

    Science.gov (United States)

    Thye, Melissa D; Ammons, Carla J; Murdaugh, Donna L; Kana, Rajesh K

    2018-07-16

    Social neuroscience research has focused on an identified network of brain regions primarily associated with processing Theory of Mind (ToM). However, ToM is a broad cognitive process, which encompasses several sub-processes, such as mental state detection and intentional attribution, and the connectivity of brain regions underlying the broader ToM network in response to paradigms assessing these sub-processes requires further characterization. Standard fMRI analyses which focus only on brain activity cannot capture information about ToM processing at a network level. An alternative method, independent component analysis (ICA), is a data-driven technique used to isolate intrinsic connectivity networks, and this approach provides insight into network-level regional recruitment. In this fMRI study, three complementary, but distinct ToM tasks assessing mental state detection (e.g. RMIE: Reading the Mind in the Eyes; RMIV: Reading the Mind in the Voice) and intentional attribution (Causality task) were each analyzed using ICA in order to separately characterize the recruitment and functional connectivity of core nodes in the ToM network in response to the sub-processes of ToM. Based on visual comparison of the derived networks for each task, the spatiotemporal network patterns were similar between the RMIE and RMIV tasks, which elicited mentalizing about the mental states of others, and these networks differed from the network derived for the Causality task, which elicited mentalizing about goal-directed actions. The medial prefrontal cortex, precuneus, and right inferior frontal gyrus were seen in the components with the highest correlation with the task condition for each of the tasks highlighting the role of these regions in general ToM processing. Using a data-driven approach, the current study captured the differences in task-related brain response to ToM in three distinct ToM paradigms. The findings of this study further elucidate the neural mechanisms associated

  5. Game Theory-Based Cooperation for Underwater Acoustic Sensor Networks: Taxonomy, Review, Research Challenges and Directions

    Directory of Open Access Journals (Sweden)

    Dalhatu Muhammed

    2018-02-01

    Full Text Available Exploring and monitoring the underwater world using underwater sensors is drawing a lot of attention these days. In this field cooperation between acoustic sensor nodes has been a critical problem due to the challenging features such as acoustic channel failure (sound signal, long propagation delay of acoustic signal, limited bandwidth and loss of connectivity. There are several proposed methods to improve cooperation between the nodes by incorporating information/game theory in the node’s cooperation. However, there is a need to classify the existing works and demonstrate their performance in addressing the cooperation issue. In this paper, we have conducted a review to investigate various factors affecting cooperation in underwater acoustic sensor networks. We study various cooperation techniques used for underwater acoustic sensor networks from different perspectives, with a concentration on communication reliability, energy consumption, and security and present a taxonomy for underwater cooperation. Moreover, we further review how the game theory can be applied to make the nodes cooperate with each other. We further analyze different cooperative game methods, where their performance on different metrics is compared. Finally, open issues and future research direction in underwater acoustic sensor networks are highlighted.

  6. Game Theory-Based Cooperation for Underwater Acoustic Sensor Networks: Taxonomy, Review, Research Challenges and Directions.

    Science.gov (United States)

    Muhammed, Dalhatu; Anisi, Mohammad Hossein; Zareei, Mahdi; Vargas-Rosales, Cesar; Khan, Anwar

    2018-02-01

    Exploring and monitoring the underwater world using underwater sensors is drawing a lot of attention these days. In this field cooperation between acoustic sensor nodes has been a critical problem due to the challenging features such as acoustic channel failure (sound signal), long propagation delay of acoustic signal, limited bandwidth and loss of connectivity. There are several proposed methods to improve cooperation between the nodes by incorporating information/game theory in the node's cooperation. However, there is a need to classify the existing works and demonstrate their performance in addressing the cooperation issue. In this paper, we have conducted a review to investigate various factors affecting cooperation in underwater acoustic sensor networks. We study various cooperation techniques used for underwater acoustic sensor networks from different perspectives, with a concentration on communication reliability, energy consumption, and security and present a taxonomy for underwater cooperation. Moreover, we further review how the game theory can be applied to make the nodes cooperate with each other. We further analyze different cooperative game methods, where their performance on different metrics is compared. Finally, open issues and future research direction in underwater acoustic sensor networks are highlighted.

  7. An examination of network position and childhood relational aggression: integrating resource control and social exchange theories.

    Science.gov (United States)

    Neal, Jennifer Watling; Cappella, Elise

    2012-01-01

    Applying resource control theory and social exchange theory, we examined the social network conditions under which elementary age children were likely to engage in relational aggression. Data on classroom peer networks and peer-nominated behaviors were collected on 671 second- through fourth-grade children in 34 urban, low-income classrooms. Nested regression models with robust cluster standard errors demonstrated that the association between children's number of relationships and their levels of relational aggression was moderated by the number of relationships that their affiliates had. Children with more peer relationships (i.e., higher network centrality) exhibited higher levels of relational aggression, but only when these relationships were with peers who had fewer connections themselves (i.e., poorly connected peers). This finding remained significant even when controlling for common predictors of relational aggression including gender, overt aggression, prosocial behavior, victimization, social preference, and perceived popularity. Results are discussed in terms of their implications for advancing the literature on childhood relational aggression and their practical applications for identifying children at risk for these behaviors. © 2012 Wiley Periodicals, Inc.

  8. Further evidence of alerted default network connectivity and association with theory of mind ability in schizophrenia.

    Science.gov (United States)

    Mothersill, Omar; Tangney, Noreen; Morris, Derek W; McCarthy, Hazel; Frodl, Thomas; Gill, Michael; Corvin, Aiden; Donohoe, Gary

    2017-06-01

    Resting-state functional magnetic resonance imaging (rs-fMRI) has repeatedly shown evidence of altered functional connectivity of large-scale networks in schizophrenia. The relationship between these connectivity changes and behaviour (e.g. symptoms, neuropsychological performance) remains unclear. Functional connectivity in 27 patients with schizophrenia or schizoaffective disorder, and 25 age and gender matched healthy controls was examined using rs-fMRI. Based on seed regions from previous studies, we examined functional connectivity of the default, cognitive control, affective and attention networks. Effects of symptom severity and theory of mind performance on functional connectivity were also examined. Patients showed increased connectivity between key nodes of the default network including the precuneus and medial prefrontal cortex compared to controls (pmind performance were both associated with altered connectivity of default regions within the patient group (pmind performance. Extending these findings by examining the effects of emerging social cognition treatments on both default connectivity and theory of mind performance is now an important goal for research. Copyright © 2016 Elsevier B.V. All rights reserved.

  9. Adaptive capacity of geographical clusters: Complexity science and network theory approach

    Science.gov (United States)

    Albino, Vito; Carbonara, Nunzia; Giannoccaro, Ilaria

    This paper deals with the adaptive capacity of geographical clusters (GCs), that is a relevant topic in the literature. To address this topic, GC is considered as a complex adaptive system (CAS). Three theoretical propositions concerning the GC adaptive capacity are formulated by using complexity theory. First, we identify three main properties of CAS s that affect the adaptive capacity, namely the interconnectivity, the heterogeneity, and the level of control, and define how the value of these properties influence the adaptive capacity. Then, we associate these properties with specific GC characteristics so obtaining the key conditions of GCs that give them the adaptive capacity so assuring their competitive advantage. To test these theoretical propositions, a case study on two real GCs is carried out. The considered GCs are modeled as networks where firms are nodes and inter-firms relationships are links. Heterogeneity, interconnectivity, and level of control are considered as network properties and thus measured by using the methods of the network theory.

  10. Large-scale transportation network congestion evolution prediction using deep learning theory.

    Science.gov (United States)

    Ma, Xiaolei; Yu, Haiyang; Wang, Yunpeng; Wang, Yinhai

    2015-01-01

    Understanding how congestion at one location can cause ripples throughout large-scale transportation network is vital for transportation researchers and practitioners to pinpoint traffic bottlenecks for congestion mitigation. Traditional studies rely on either mathematical equations or simulation techniques to model traffic congestion dynamics. However, most of the approaches have limitations, largely due to unrealistic assumptions and cumbersome parameter calibration process. With the development of Intelligent Transportation Systems (ITS) and Internet of Things (IoT), transportation data become more and more ubiquitous. This triggers a series of data-driven research to investigate transportation phenomena. Among them, deep learning theory is considered one of the most promising techniques to tackle tremendous high-dimensional data. This study attempts to extend deep learning theory into large-scale transportation network analysis. A deep Restricted Boltzmann Machine and Recurrent Neural Network architecture is utilized to model and predict traffic congestion evolution based on Global Positioning System (GPS) data from taxi. A numerical study in Ningbo, China is conducted to validate the effectiveness and efficiency of the proposed method. Results show that the prediction accuracy can achieve as high as 88% within less than 6 minutes when the model is implemented in a Graphic Processing Unit (GPU)-based parallel computing environment. The predicted congestion evolution patterns can be visualized temporally and spatially through a map-based platform to identify the vulnerable links for proactive congestion mitigation.

  11. Large-scale transportation network congestion evolution prediction using deep learning theory.

    Directory of Open Access Journals (Sweden)

    Xiaolei Ma

    Full Text Available Understanding how congestion at one location can cause ripples throughout large-scale transportation network is vital for transportation researchers and practitioners to pinpoint traffic bottlenecks for congestion mitigation. Traditional studies rely on either mathematical equations or simulation techniques to model traffic congestion dynamics. However, most of the approaches have limitations, largely due to unrealistic assumptions and cumbersome parameter calibration process. With the development of Intelligent Transportation Systems (ITS and Internet of Things (IoT, transportation data become more and more ubiquitous. This triggers a series of data-driven research to investigate transportation phenomena. Among them, deep learning theory is considered one of the most promising techniques to tackle tremendous high-dimensional data. This study attempts to extend deep learning theory into large-scale transportation network analysis. A deep Restricted Boltzmann Machine and Recurrent Neural Network architecture is utilized to model and predict traffic congestion evolution based on Global Positioning System (GPS data from taxi. A numerical study in Ningbo, China is conducted to validate the effectiveness and efficiency of the proposed method. Results show that the prediction accuracy can achieve as high as 88% within less than 6 minutes when the model is implemented in a Graphic Processing Unit (GPU-based parallel computing environment. The predicted congestion evolution patterns can be visualized temporally and spatially through a map-based platform to identify the vulnerable links for proactive congestion mitigation.

  12. Game Theory-Based Cooperation for Underwater Acoustic Sensor Networks: Taxonomy, Review, Research Challenges and Directions

    Science.gov (United States)

    Muhammed, Dalhatu; Anisi, Mohammad Hossein; Vargas-Rosales, Cesar; Khan, Anwar

    2018-01-01

    Exploring and monitoring the underwater world using underwater sensors is drawing a lot of attention these days. In this field cooperation between acoustic sensor nodes has been a critical problem due to the challenging features such as acoustic channel failure (sound signal), long propagation delay of acoustic signal, limited bandwidth and loss of connectivity. There are several proposed methods to improve cooperation between the nodes by incorporating information/game theory in the node’s cooperation. However, there is a need to classify the existing works and demonstrate their performance in addressing the cooperation issue. In this paper, we have conducted a review to investigate various factors affecting cooperation in underwater acoustic sensor networks. We study various cooperation techniques used for underwater acoustic sensor networks from different perspectives, with a concentration on communication reliability, energy consumption, and security and present a taxonomy for underwater cooperation. Moreover, we further review how the game theory can be applied to make the nodes cooperate with each other. We further analyze different cooperative game methods, where their performance on different metrics is compared. Finally, open issues and future research direction in underwater acoustic sensor networks are highlighted. PMID:29389874

  13. Bombing Alone: Tracing the Motivations and Antecedent Behaviors of Lone-Actor Terrorists*,†,‡

    Science.gov (United States)

    Gill, Paul; Horgan, John; Deckert, Paige

    2014-01-01

    This article analyzes the sociodemographic network characteristics and antecedent behaviors of 119 lone-actor terrorists. This marks a departure from existing analyses by largely focusing upon behavioral aspects of each offender. This article also examines whether lone-actor terrorists differ based on their ideologies or network connectivity. The analysis leads to seven conclusions. There was no uniform profile identified. In the time leading up to most lone-actor terrorist events, other people generally knew about the offender’s grievance, extremist ideology, views, and/or intent to engage in violence. A wide range of activities and experiences preceded lone actors’ plots or events. Many but not all lone-actor terrorists were socially isolated. Lone-actor terrorists regularly engaged in a detectable and observable range of activities with a wider pressure group, social movement, or terrorist organization. Lone-actor terrorist events were rarely sudden and impulsive. There were distinguishable behavioral differences between subgroups. The implications for policy conclude this article. PMID:24313297

  14. Criminal groups and transnational illegal markets : A more detailed examination on the basis of Social Network Theory

    NARCIS (Netherlands)

    Bruinsma, Gerben; Bernasco, Wim

    In the study of organised crime, the traditional view of criminal groups as centrally controlled organisations has been replaced by the notion of criminal networks. However, little use has been made of concepts and theories of social networks that have developed in other social sciences. This paper

  15. Design of control rooms. Collaboration between different actors during the design of new and modernized control rooms

    International Nuclear Information System (INIS)

    Johansson, Bjoern J. E.; Gonzalez, Natalia

    2012-01-01

    Swedish nuclear power industry is currently undergoing, as well as planning, a number of upgrades of their control rooms. When changes are made to an NPP, they are conducted within the frame of a design process. The design process controls a number of different domains, such as technical solutions etc, but also affects and is affected by the interactions between Man, Technology and Organisation (MTO). MTO is central for creating safe system solutions. However, in the design process, unplanned events often occur in comparison to what was originally planned. This work aimed to analyse the design process and the involved actors' roles using activity theory with the purpose of creating an understanding of the design process. Activity theory can be seen as a way of understanding individuals and groups and the context they create by analysing the structure and process that their activities are part of. It can therefore be a good tool for analysing the complexity of the design process of a control room. The study has shown that many actors are involved in the design process and that all of them partly drive their own agendas, which may lead to contradictions within the design process. Important conclusions are that it perhaps not is necessary to eliminate all contradictions, but it is important to be aware of them. It is considered, among the informants in the study, that a working communication exists between the actors in the design process, but it is also evident that there is no given method for this, something that also counts for MTO-questions and the communication regarding those. A number of recommendations on how to support the communication process are given. Although there were some difficulties in using activity theory, it is believed that it could be useful for creating an overview of the design process and its actors from different organisations. Activity networks could be bound together in different ways and this provided opportunities to identify possible

  16. Causal relationship between the global foreign exchange market based on complex networks and entropy theory

    International Nuclear Information System (INIS)

    Cao, Guangxi; Zhang, Qi; Li, Qingchen

    2017-01-01

    Highlights: • Mutual information is used as the edge weights of nodes instead of PCC, which overcomes the shortcomings of linear correlation functions. • SGD turns into a new cluster center and gradually becomes a point connecting the Asian and European clusters during and after the US sub-prime crisis. • Liang's entropy theory, which has not been adopted before in the global foreign exchange market, is considered. - Abstract: The foreign exchange (FX) market is a typical complex dynamic system under the background of exchange rate marketization reform and is an important part of the financial market. This study aims to generate an international FX network based on complex network theory. This study employs the mutual information method to judge the nonlinear characteristics of 54 major currencies in international FX markets. Through this method, we find that the FX network possesses a small average path length and a large clustering coefficient under different thresholds and that it exhibits small-world characteristics as a whole. Results show that the relationship between FX rates is close. Volatility can quickly transfer in the whole market, and the FX volatility of influential individual states transfers at a fast pace and a large scale. The period from July 21, 2005 to March 31, 2015 is subdivided into three sub-periods (i.e., before, during, and after the US sub-prime crisis) to analyze the topology evolution of FX markets using the maximum spanning tree approach. Results show that the USD gradually lost its core position, EUR remained a stable center, and the center of the Asian cluster became unstable. Liang's entropy theory is used to analyze the causal relationship between the four large clusters of the world.

  17. An object recognition method based on fuzzy theory and BP networks

    Science.gov (United States)

    Wu, Chuan; Zhu, Ming; Yang, Dong

    2006-01-01

    It is difficult to choose eigenvectors when neural network recognizes object. It is possible that the different object eigenvectors is similar or the same object eigenvectors is different under scaling, shifting, rotation if eigenvectors can not be chosen appropriately. In order to solve this problem, the image is edged, the membership function is reconstructed and a new threshold segmentation method based on fuzzy theory is proposed to get the binary image. Moment invariant of binary image is extracted and normalized. Some time moment invariant is too small to calculate effectively so logarithm of moment invariant is taken as input eigenvectors of BP network. The experimental results demonstrate that the proposed approach could recognize the object effectively, correctly and quickly.

  18. Characterization and detection of thermoacoustic combustion oscillations based on statistical complexity and complex-network theory

    Science.gov (United States)

    Murayama, Shogo; Kinugawa, Hikaru; Tokuda, Isao T.; Gotoda, Hiroshi

    2018-02-01

    We present an experimental study on the characterization of dynamic behavior of flow velocity field during thermoacoustic combustion oscillations in a turbulent confined combustor from the viewpoints of statistical complexity and complex-network theory, involving detection of a precursor of thermoacoustic combustion oscillations. The multiscale complexity-entropy causality plane clearly shows the possible presence of two dynamics, noisy periodic oscillations and noisy chaos, in the shear layer regions (1) between the outer recirculation region in the dump plate and a recirculation flow in the wake of the centerbody and (2) between the outer recirculation region in the dump plate and a vortex breakdown bubble away from the centerbody. The vertex strength in the turbulence network and the community structure of the vorticity field can identify the vortical interactions during thermoacoustic combustion oscillations. Sequential horizontal visibility graph motifs are useful for capturing a precursor of themoacoustic combustion oscillations.

  19. Securing mobile ad hoc networks using danger theory-based artificial immune algorithm.

    Science.gov (United States)

    Abdelhaq, Maha; Alsaqour, Raed; Abdelhaq, Shawkat

    2015-01-01

    A mobile ad hoc network (MANET) is a set of mobile, decentralized, and self-organizing nodes that are used in special cases, such as in the military. MANET properties render the environment of this network vulnerable to different types of attacks, including black hole, wormhole and flooding-based attacks. Flooding-based attacks are one of the most dangerous attacks that aim to consume all network resources and thus paralyze the functionality of the whole network. Therefore, the objective of this paper is to investigate the capability of a danger theory-based artificial immune algorithm called the mobile dendritic cell algorithm (MDCA) to detect flooding-based attacks in MANETs. The MDCA applies the dendritic cell algorithm (DCA) to secure the MANET with additional improvements. The MDCA is tested and validated using Qualnet v7.1 simulation tool. This work also introduces a new simulation module for a flooding attack called the resource consumption attack (RCA) using Qualnet v7.1. The results highlight the high efficiency of the MDCA in detecting RCAs in MANETs.

  20. A User Cooperation Stimulating Strategy Based on Cooperative Game Theory in Cooperative Relay Networks

    Directory of Open Access Journals (Sweden)

    Ping Zhang

    2009-01-01

    Full Text Available This paper proposes a user cooperation stimulating strategy among rational users. The strategy is based on cooperative game theory and enacted in the context of cooperative relay networks. Using the pricing-based mechanism, the system is modeled initially with two nodes and a Base Station (BS. Within this framework, each node is treated as a rational decision maker. To this end, each node can decide whether to cooperate and how to cooperate. Cooperative game theory assists in providing an optimal system utility and provides fairness among users. Under different cooperative forwarding modes, certain questions are carefully investigated, including “what is each node's best reaction to maximize its utility?” and “what is the optimal reimbursement to encourage cooperation?” Simulation results show that the nodes benefit from the proposed cooperation stimulating strategy in terms of utility and thus justify the fairness between each user.

  1. A User Cooperation Stimulating Strategy Based on Cooperative Game Theory in Cooperative Relay Networks

    Directory of Open Access Journals (Sweden)

    Jiang Fan

    2009-01-01

    Full Text Available This paper proposes a user cooperation stimulating strategy among rational users. The strategy is based on cooperative game theory and enacted in the context of cooperative relay networks. Using the pricing-based mechanism, the system is modeled initially with two nodes and a Base Station (BS. Within this framework, each node is treated as a rational decision maker. To this end, each node can decide whether to cooperate and how to cooperate. Cooperative game theory assists in providing an optimal system utility and provides fairness among users. Under different cooperative forwarding modes, certain questions are carefully investigated, including "what is each node's best reaction to maximize its utility?" and "what is the optimal reimbursement to encourage cooperation?" Simulation results show that the nodes benefit from the proposed cooperation stimulating strategy in terms of utility and thus justify the fairness between each user.

  2. Cryptographic Puzzles and Game Theory against DoS and DDoS attacks in Networks

    DEFF Research Database (Denmark)

    Mikalas, Antonis; Komninos, Nikos; Prasad, Neeli R.

    2008-01-01

    In this chapter, we present techniques to defeat Denial of Service (DoS) and Distributed Denial of Service (DDoS) attacks. In the _rst part, we describe client puzzle techniques that are based on the idea of computationally exhausting a malicious user when he attempts to launch an attack. In the ......In this chapter, we present techniques to defeat Denial of Service (DoS) and Distributed Denial of Service (DDoS) attacks. In the _rst part, we describe client puzzle techniques that are based on the idea of computationally exhausting a malicious user when he attempts to launch an attack....... In the second part we are introducing some basic principles of game theory and we discuss how game theoretical frameworks can protect computer networks. Finally, we show techniques that combine client puzzles with game theory in order to provide DoS and DDoS resilience....

  3. Optimal design of hydrometric monitoring networks with dynamic components based on Information Theory

    Science.gov (United States)

    Alfonso, Leonardo; Chacon, Juan; Solomatine, Dimitri

    2016-04-01

    The EC-FP7 WeSenseIt project proposes the development of a Citizen Observatory of Water, aiming at enhancing environmental monitoring and forecasting with the help of citizens equipped with low-cost sensors and personal devices such as smartphones and smart umbrellas. In this regard, Citizen Observatories may complement the limited data availability in terms of spatial and temporal density, which is of interest, among other areas, to improve hydraulic and hydrological models. At this point, the following question arises: how can citizens, who are part of a citizen observatory, be optimally guided so that the data they collect and send is useful to improve modelling and water management? This research proposes a new methodology to identify the optimal location and timing of potential observations coming from moving sensors of hydrological variables. The methodology is based on Information Theory, which has been widely used in hydrometric monitoring design [1-4]. In particular, the concepts of Joint Entropy, as a measure of the amount of information that is contained in a set of random variables, which, in our case, correspond to the time series of hydrological variables captured at given locations in a catchment. The methodology presented is a step forward in the state of the art because it solves the multiobjective optimisation problem of getting simultaneously the minimum number of informative and non-redundant sensors needed for a given time, so that the best configuration of monitoring sites is found at every particular moment in time. To this end, the existing algorithms have been improved to make them efficient. The method is applied to cases in The Netherlands, UK and Italy and proves to have a great potential to complement the existing in-situ monitoring networks. [1] Alfonso, L., A. Lobbrecht, and R. Price (2010a), Information theory-based approach for location of monitoring water level gauges in polders, Water Resour. Res., 46(3), W03528 [2] Alfonso, L., A

  4. Non-state actors in control of territory as 'actors of protection' in international refugee law

    NARCIS (Netherlands)

    Karavias, M.

    2015-01-01

    This article examines the concept of non-state ‘actors of protection’ in international refugee law. This concept breaks with traditional State-centric readings of international law, as it connotes that a non-state actor may offer ‘protection’ against persecution, comparable to that normally offered

  5. Networks as Tools for Sustainable Urban Development

    DEFF Research Database (Denmark)

    Jensen, Jesper Ole; Tollin, Nicola

    will be discussed through a case study of a Danish municipal network on Sustainable Development, Dogme 20001. This network has become quite successful in terms of learning and innovation, committing actors, and influencing local policies, to a larger extent than other SUD-networks the municipalities are involved in....... By applying the GREMI2-theories of “innovative milieux” (Aydalot, 1986; Camagni, 1991) to the case study, we will suggest some reasons for the benefits achieved by the Dogme-network, compared to other networks. This analysis will point to the existence of an “innovative milieu” on sustainability within......Due to the increasing number of networks related to sustainable development (SUD) the paper focuses on understanding in which way networks can be considered useful tools for sustainable urban development, taking particularly into consideration the networks potential of spreading innovative policies...

  6. Networks as Tools for Urban Sustainability

    DEFF Research Database (Denmark)

    Jensen, Jesper Ole; Tollin, Nicola

    2004-01-01

    Due to the increasing number of networks related to sustainable development (SUD) the paper focuses on understanding in which way networks can be considered useful tools for sustainable urban development, taking particularly into consideration the networks potential of spreading innovative policies...... will be discussed through a case study of a Danish municipal network on Sustainable Development, Dogme 2000 . This network has become quite successful in terms of learning and innovation, committing actors, and influencing local policies, to a larger extent than other SUD-networks the municipalities are involved in....... By applying the GREMI -theories of “innovative milieux” (Aydalot, 1986; Camagni, 1991) to the case study, we will suggest some reasons for the benefits achieved by the Dogme-network, compared to other networks. This analysis will point to the existence of an “innovative milieu” on sustainability within...

  7. Unifying Pore Network Modeling, Continuous Time Random Walk Theory and Experiment - Accomplishments and Future Directions

    Science.gov (United States)

    Bijeljic, B.

    2008-05-01

    This talk will describe and highlight the advantages offered by a methodology that unifies pore network modeling, CTRW theory and experiment in description of solute dispersion in porous media. Solute transport in a porous medium is characterized by the interplay of advection and diffusion (described by Peclet number, Pe) that cause spreading of solute particles. This spreading is traditionally described by dispersion coefficients, D, defined by σ 2 = 2Dt, where σ 2 is the variance of the solute position and t is the time. Using a pore-scale network model based on particle tracking, the rich Peclet- number dependence of dispersion coefficient is predicted from first principles and is shown to compare well with experimental data for restricted diffusion, transition, power-law and mechanical dispersion regimes in the asymptotic limit. In the asymptotic limit D is constant and can be used in an averaged advection-dispersion equation. However, it is highly important to recognize that, until the velocity field is fully sampled, the particle transport is non-Gaussian and D possesses temporal or spatial variation. Furthermore, temporal probability density functions (PDF) of tracer particles are studied in pore networks and an excellent agreement for the spectrum of transition times for particles from pore to pore is obtained between network model results and CTRW theory. Based on the truncated power-law interpretation of PDF-s, the physical origin of the power-law scaling of dispersion coefficient vs. Peclet number has been explained for unconsolidated porous media, sands and a number of sandstones, arriving at the same conclusion from numerical network modelling, analytic CTRW theory and experiment. Future directions for further applications of the methodology presented are discussed in relation to the scale- dependent solute dispersion and reactive transport. Significance of pre-asymptotic dispersion in porous media is addressed from pore-scale upwards and the impact

  8. Real-Time Dynamics in U(1 Lattice Gauge Theories with Tensor Networks

    Directory of Open Access Journals (Sweden)

    T. Pichler

    2016-03-01

    Full Text Available Tensor network algorithms provide a suitable route for tackling real-time-dependent problems in lattice gauge theories, enabling the investigation of out-of-equilibrium dynamics. We analyze a U(1 lattice gauge theory in (1+1 dimensions in the presence of dynamical matter for different mass and electric-field couplings, a theory akin to quantum electrodynamics in one dimension, which displays string breaking: The confining string between charges can spontaneously break during quench experiments, giving rise to charge-anticharge pairs according to the Schwinger mechanism. We study the real-time spreading of excitations in the system by means of electric-field and particle fluctuations. We determine a dynamical state diagram for string breaking and quantitatively evaluate the time scales for mass production. We also show that the time evolution of the quantum correlations can be detected via bipartite von Neumann entropies, thus demonstrating that the Schwinger mechanism is tightly linked to entanglement spreading. To present a variety of possible applications of this simulation platform, we show how one could follow the real-time scattering processes between mesons and the creation of entanglement during scattering processes. Finally, we test the quality of quantum simulations of these dynamics, quantifying the role of possible imperfections in cold atoms, trapped ions, and superconducting circuit systems. Our results demonstrate how entanglement properties can be used to deepen our understanding of basic phenomena in the real-time dynamics of gauge theories such as string breaking and collisions.

  9. Postdecisional counterfactual thinking by actors and readers.

    Science.gov (United States)

    Girotto, Vittorio; Ferrante, Donatella; Pighin, Stefania; Gonzalez, Michel

    2007-06-01

    How do individuals think counterfactually about the outcomes of their decisions? Most previous studies have investigated how readers think about fictional stories, rather than how actors think about events they have actually experienced. We assumed that differences in individuals' roles (actor vs. reader) can make different information available, which in turn can affect counterfactual thinking. Hence, we predicted an effect of role on postdecisional counterfactual thinking. Reporting the results of eight studies, we show that readers undo the negative outcome of a story by undoing the protagonist's choice to tackle a given problem, rather than the protagonist's unsuccessful attempt to solve it. But actors who make the same choice and experience the same negative outcome as the protagonist undo this outcome by altering features of the problem. We also show that this effect does not depend on motivational factors. These results contradict current accounts of counterfactual thinking and demonstrate the necessity of investigating the counterfactual thoughts of individuals in varied roles.

  10. ACToR - Aggregated Computational Toxicology Resource

    International Nuclear Information System (INIS)

    Judson, Richard; Richard, Ann; Dix, David; Houck, Keith; Elloumi, Fathi; Martin, Matthew; Cathey, Tommy; Transue, Thomas R.; Spencer, Richard; Wolf, Maritja

    2008-01-01

    ACToR (Aggregated Computational Toxicology Resource) is a database and set of software applications that bring into one central location many types and sources of data on environmental chemicals. Currently, the ACToR chemical database contains information on chemical structure, in vitro bioassays and in vivo toxicology assays derived from more than 150 sources including the U.S. Environmental Protection Agency (EPA), Centers for Disease Control (CDC), U.S. Food and Drug Administration (FDA), National Institutes of Health (NIH), state agencies, corresponding government agencies in Canada, Europe and Japan, universities, the World Health Organization (WHO) and non-governmental organizations (NGOs). At the EPA National Center for Computational Toxicology, ACToR helps manage large data sets being used in a high-throughput environmental chemical screening and prioritization program called ToxCast TM

  11. Celebrating the Tenth Networked Learning Conference: Looking Back and Moving Forward

    DEFF Research Database (Denmark)

    de Laat, Maarten; Ryberg, Thomas

    2018-01-01

    , actor network theory), learning environments and social media (e.g. LMS, MOOC, Virtual Worlds, Twitter, Facebook), technologies (e.g. phone, laptop, tablet), methodology (e.g. quantitative, qualitative) and related research in the domain of e-learning (e-learning, CSCL, TEL). The findings are placed...

  12. Virtual Learning Environments as Sociomaterial Agents in the Network of Teaching Practice

    Science.gov (United States)

    Johannesen, Monica; Erstad, Ola; Habib, Laurence

    2012-01-01

    This article presents findings related to the sociomaterial agency of educators and their practice in Norwegian education. Using actor-network theory, we ask how Virtual Learning Environments (VLEs) negotiate the agency of educators and how they shape their teaching practice. Since the same kinds of VLE tools have been widely implemented…

  13. Writing Programs as Distributed Networks: A Materialist Approach to University-Community Digital Media Literacy

    Science.gov (United States)

    Comstock, Michelle

    2006-01-01

    This article addresses how community-university digital media literacy projects are redefining literacy, literate practices, and institutions. Using Actor-Network Theory (ANT), which emphasizes the organizing process itself, I analyze the shifting definitions of literacy within one particular university-community collaboration. My analysis…

  14. Fractal Point Process and Queueing Theory and Application to Communication Networks

    National Research Council Canada - National Science Library

    Wornel, Gregory

    1999-01-01

    .... A unifying theme in the approaches to these problems has been an integration of interrelated perspectives from communication theory, information theory, signal processing theory, and control theory...

  15. Lone Actors: Challenges and Opportunities for Countering Violent Extremism

    NARCIS (Netherlands)

    Spaaij, R.; Richman, A.; Sharan, Y.

    2015-01-01

    This paper explores some of the key challenges and opportunities concerning the prevention and control of lone actor terrorism. It is argued that lone actors do not operate in a social vacuum and that the interaction points between lone actors and their social environments can render lone actors

  16. Extraction of business relationships in supply networks using statistical learning theory.

    Science.gov (United States)

    Zuo, Yi; Kajikawa, Yuya; Mori, Junichiro

    2016-06-01

    Supply chain management represents one of the most important scientific streams of operations research. The supply of energy, materials, products, and services involves millions of transactions conducted among national and local business enterprises. To deliver efficient and effective support for supply chain design and management, structural analyses and predictive models of customer-supplier relationships are expected to clarify current enterprise business conditions and to help enterprises identify innovative business partners for future success. This article presents the outcomes of a recent structural investigation concerning a supply network in the central area of Japan. We investigated the effectiveness of statistical learning theory to express the individual differences of a supply chain of enterprises within a certain business community using social network analysis. In the experiments, we employ support vector machine to train a customer-supplier relationship model on one of the main communities extracted from a supply network in the central area of Japan. The prediction results reveal an F-value of approximately 70% when the model is built by using network-based features, and an F-value of approximately 77% when the model is built by using attribute-based features. When we build the model based on both, F-values are improved to approximately 82%. The results of this research can help to dispel the implicit design space concerning customer-supplier relationships, which can be explored and refined from detailed topological information provided by network structures rather than from traditional and attribute-related enterprise profiles. We also investigate and discuss differences in the predictive accuracy of the model for different sizes of enterprises and types of business communities.

  17. Extraction of business relationships in supply networks using statistical learning theory

    Directory of Open Access Journals (Sweden)

    Yi Zuo

    2016-06-01

    Full Text Available Supply chain management represents one of the most important scientific streams of operations research. The supply of energy, materials, products, and services involves millions of transactions conducted among national and local business enterprises. To deliver efficient and effective support for supply chain design and management, structural analyses and predictive models of customer–supplier relationships are expected to clarify current enterprise business conditions and to help enterprises identify innovative business partners for future success. This article presents the outcomes of a recent structural investigation concerning a supply network in the central area of Japan. We investigated the effectiveness of statistical learning theory to express the individual differences of a supply chain of enterprises within a certain business community using social network analysis. In the experiments, we employ support vector machine to train a customer–supplier relationship model on one of the main communities extracted from a supply network in the central area of Japan. The prediction results reveal an F-value of approximately 70% when the model is built by using network-based features, and an F-value of approximately 77% when the model is built by using attribute-based features. When we build the model based on both, F-values are improved to approximately 82%. The results of this research can help to dispel the implicit design space concerning customer–supplier relationships, which can be explored and refined from detailed topological information provided by network structures rather than from traditional and attribute-related enterprise profiles. We also investigate and discuss differences in the predictive accuracy of the model for different sizes of enterprises and types of business communities.

  18. Reinforcement learning using a continuous time actor-critic framework with spiking neurons.

    Directory of Open Access Journals (Sweden)

    Nicolas Frémaux

    2013-04-01

    Full Text Available Animals repeat rewarded behaviors, but the physiological basis of reward-based learning has only been partially elucidated. On one hand, experimental evidence shows that the neuromodulator dopamine carries information about rewards and affects synaptic plasticity. On the other hand, the theory of reinforcement learning provides a framework for reward-based learning. Recent models of reward-modulated spike-timing-dependent plasticity have made first steps towards bridging the gap between the two approaches, but faced two problems. First, reinforcement learning is typically formulated in a discrete framework, ill-adapted to the description of natural situations. Second, biologically plausible models of reward-modulated spike-timing-dependent plasticity require precise calculation of the reward prediction error, yet it remains to be shown how this can be computed by neurons. Here we propose a solution to these problems by extending the continuous temporal difference (TD learning of Doya (2000 to the case of spiking neurons in an actor-critic network operating in continuous time, and with continuous state and action representations. In our model, the critic learns to predict expected future rewards in real time. Its activity, together with actual rewards, conditions the delivery of a neuromodulatory TD signal to itself and to the actor, which is responsible for action choice. In simulations, we show that such an architecture can solve a Morris water-maze-like navigation task, in a number of trials consistent with reported animal performance. We also use our model to solve the acrobot and the cartpole problems, two complex motor control tasks. Our model provides a plausible way of computing reward prediction error in the brain. Moreover, the analytically derived learning rule is consistent with experimental evidence for dopamine-modulated spike-timing-dependent plasticity.

  19. Analytical transport network theory to guide the design of 3-D microstructural networks in energy materials: Part 1. Flow without reactions

    Science.gov (United States)

    Cocco, Alex P.; Nakajo, Arata; Chiu, Wilson K. S.

    2017-12-01

    We present a fully analytical, heuristic model - the "Analytical Transport Network Model" - for steady-state, diffusive, potential flow through a 3-D network. Employing a combination of graph theory, linear algebra, and geometry, the model explicitly relates a microstructural network's topology and the morphology of its channels to an effective material transport coefficient (a general term meant to encompass, e.g., conductivity or diffusion coefficient). The model's transport coefficient predictions agree well with those from electrochemical fin (ECF) theory and finite element analysis (FEA), but are computed 0.5-1.5 and 5-6 orders of magnitude faster, respectively. In addition, the theory explicitly relates a number of morphological and topological parameters directly to the transport coefficient, whereby the distributions that characterize the structure are readily available for further analysis. Furthermore, ATN's explicit development provides insight into the nature of the tortuosity factor and offers the potential to apply theory from network science and to consider the optimization of a network's effective resistance in a mathematically rigorous manner. The ATN model's speed and relative ease-of-use offer the potential to aid in accelerating the design (with respect to transport), and thus reducing the cost, of energy materials.

  20. The Role of Social Networking Services in eParticipation

    DEFF Research Database (Denmark)

    Sæbø, Øystein; Rose, Jeremy; Nyvang, Tom

    2009-01-01

    , content-generation and the development of loosely-coupled communities. They provide the forum for much discussion and interaction. In this respect social networking could contribute to solve some of the problems of engaging their users that eParticipation services often struggle with. This paper...... and social networking because democratic systems favour the interests of larger groups of citizens --- the more voices behind a political proposition, the greater its chances of success. In this context of challenges the study of social networking on the internet and social network theory offers valuable...... insights into the practices and theories of citizen engagement. Social network theory focuses on the chains of relationships that social actors communicate and act within. Some social networking services on the internet attract large numbers of users, and apparently sustain a great deal of interaction...

  1. Intra-Organizational Two-Mode Networks Analysis of a Public Organization

    Directory of Open Access Journals (Sweden)

    Anna Ujwary-Gil

    2017-10-01

    Full Text Available The article focuses on the analysis of intra-organizational and two-mode networks of knowledge, resources and tasks. Each of these networks consists of a human and non-human actor in the terminology of the actor-network theory (ANT, or of only non-human actors. This type of research is rare in the theory of organization and management, even though the first article on meta-networks dates back to nearly two decades ago (Krackhardt & Carley, 1998. The article analyses the prominences and ties between particular network nodes (actors, knowledge, resources and tasks, assessing their effective use in an organization. The author selected a public organization operating in the university education sector, where saturation with communication, resource and knowledge-sharing are relatively high. The application of the network analysis provides a totally different perspective on an organization, taking into account the inter-relationship, which allows a holistic (complex outlook on the analyzed object. Especially, as it measures particular nodes as related to one another, not as isolated variables, as in classical research, where observations are independent.

  2. Real-time flood forecasts & risk assessment using a possibility-theory based fuzzy neural network

    Science.gov (United States)

    Khan, U. T.

    2016-12-01

    Globally floods are one of the most devastating natural disasters and improved flood forecasting methods are essential for better flood protection in urban areas. Given the availability of high resolution real-time datasets for flood variables (e.g. streamflow and precipitation) in many urban areas, data-driven models have been effectively used to predict peak flow rates in river; however, the selection of input parameters for these types of models is often subjective. Additionally, the inherit uncertainty associated with data models along with errors in extreme event observations means that uncertainty quantification is essential. Addressing these concerns will enable improved flood forecasting methods and provide more accurate flood risk assessments. In this research, a new type of data-driven model, a quasi-real-time updating fuzzy neural network is developed to predict peak flow rates in urban riverine watersheds. A possibility-to-probability transformation is first used to convert observed data into fuzzy numbers. A possibility theory based training regime is them used to construct the fuzzy parameters and the outputs. A new entropy-based optimisation criterion is used to train the network. Two existing methods to select the optimum input parameters are modified to account for fuzzy number inputs, and compared. These methods are: Entropy-Wavelet-based Artificial Neural Network (EWANN) and Combined Neural Pathway Strength Analysis (CNPSA). Finally, an automated algorithm design to select the optimum structure of the neural network is implemented. The overall impact of each component of training this network is to replace the traditional ad hoc network configuration methods, with one based on objective criteria. Ten years of data from the Bow River in Calgary, Canada (including two major floods in 2005 and 2013) are used to calibrate and test the network. The EWANN method selected lagged peak flow as a candidate input, whereas the CNPSA method selected lagged

  3. Parametric sensitivity analysis for biochemical reaction networks based on pathwise information theory.

    Science.gov (United States)

    Pantazis, Yannis; Katsoulakis, Markos A; Vlachos, Dionisios G

    2013-10-22

    Stochastic modeling and simulation provide powerful predictive methods for the intrinsic understanding of fundamental mechanisms in complex biochemical networks. Typically, such mathematical models involve networks of coupled jump stochastic processes with a large number of parameters that need to be suitably calibrated against experimental data. In this direction, the parameter sensitivity analysis of reaction networks is an essential mathematical and computational tool, yielding information regarding the robustness and the identifiability of model parameters. However, existing sensitivity analysis approaches such as variants of the finite difference method can have an overwhelming computational cost in models with a high-dimensional parameter space. We develop a sensitivity analysis methodology suitable for complex stochastic reaction networks with a large number of parameters. The proposed approach is based on Information Theory methods and relies on the quantification of information loss due to parameter perturbations between time-series distributions. For this reason, we need to work on path-space, i.e., the set consisting of all stochastic trajectories, hence the proposed approach is referred to as "pathwise". The pathwise sensitivity analysis method is realized by employing the rigorously-derived Relative Entropy Rate, which is directly computable from the propensity functions. A key aspect of the method is that an associated pathwise Fisher Information Matrix (FIM) is defined, which in turn constitutes a gradient-free approach to quantifying parameter sensitivities. The structure of the FIM turns out to be block-diagonal, revealing hidden parameter dependencies and sensitivities in reaction networks. As a gradient-free method, the proposed sensitivity analysis provides a significant advantage when dealing with complex stochastic systems with a large number of parameters. In addition, the knowledge of the structure of the FIM can allow to efficiently address

  4. Iranian Sanctions: An Actor-Centric Analysis

    Science.gov (United States)

    2012-03-01

    cultivated to counterbalance other actors in the system who opposed Khamenei’s ascension, based on his weak religious credentials.42 These security...trumped up religious infraction.256 The bonyads are the Iranian economy’s dominating revenue generating entity outside the oil sector,257 mushrooming in

  5. An Erlang Implementation of Multiparty Session Actors

    Directory of Open Access Journals (Sweden)

    Simon Fowler

    2016-08-01

    Full Text Available By requiring co-ordination to take place using explicit message passing instead of relying on shared memory, actor-based programming languages have been shown to be effective tools for building reliable and fault-tolerant distributed systems. Although naturally communication-centric, communication patterns in actor-based applications remain informally specified, meaning that errors in communication are detected late, if at all. Multiparty session types are a formalism to describe, at a global level, the interactions between multiple communicating entities. This article describes the implementation of a prototype framework for monitoring Erlang/OTP gen_server applications against multiparty session types, showing how previous work on multiparty session actors can be adapted to a purely actor-based language, and how monitor violations and termination of session participants can be reported in line with the Erlang mantra of "let it fail". Finally, the framework is used to implement two case studies: an adaptation of a freely-available DNS server, and a chat server.

  6. Corporate actors in Western European television news

    NARCIS (Netherlands)

    Verhoeven, P.

    2009-01-01

    News about corporations can be understood as an interdependent relationship among the public relations function, organizational logic and the logic of the media. This research addresses the visibility and role of corporate actors in Western European public television news. A quantitative content

  7. Policy Actors: Doing Policy Work in Schools

    Science.gov (United States)

    Ball, Stephen J.; Maguire, Meg; Braun, Annette; Hoskins, Kate

    2011-01-01

    This paper considers the "policy work" of teacher actors in schools. It focuses on the "problem of meaning" and offers a typology of roles and positions through which teachers engage with policy and with which policies get "enacted". It argues that "policy work" is made up of a set of complex and…

  8. Optimization of hydrometric monitoring network in urban drainage systems using information theory.

    Science.gov (United States)

    Yazdi, J

    2017-10-01

    Regular and continuous monitoring of urban runoff in both quality and quantity aspects is of great importance for controlling and managing surface runoff. Due to the considerable costs of establishing new gauges, optimization of the monitoring network is essential. This research proposes an approach for site selection of new discharge stations in urban areas, based on entropy theory in conjunction with multi-objective optimization tools and numerical models. The modeling framework provides an optimal trade-off between the maximum possible information content and the minimum shared information among stations. This approach was applied to the main surface-water collection system in Tehran to determine new optimal monitoring points under the cost considerations. Experimental results on this drainage network show that the obtained cost-effective designs noticeably outperform the consulting engineers' proposal in terms of both information contents and shared information. The research also determined the highly frequent sites at the Pareto front which might be important for decision makers to give a priority for gauge installation on those locations of the network.

  9. Aberrant functioning of the theory-of-mind network in children and adolescents with autism.

    Science.gov (United States)

    Kana, Rajesh K; Maximo, Jose O; Williams, Diane L; Keller, Timothy A; Schipul, Sarah E; Cherkassky, Vladimir L; Minshew, Nancy J; Just, Marcel Adam

    2015-01-01

    Theory-of-mind (ToM), the ability to infer people's thoughts and feelings, is a pivotal skill in effective social interactions. Individuals with autism spectrum disorders (ASD) have been found to have altered ToM skills, which significantly impacts the quality of their social interactions. Neuroimaging studies have reported altered activation of the ToM cortical network, especially in adults with autism, yet little is known about the brain responses underlying ToM in younger individuals with ASD. This functional magnetic resonance imaging (fMRI) study investigated the neural mechanisms underlying ToM in high-functioning children and adolescents with ASD and matched typically developing (TD) peers. fMRI data were acquired from 13 participants with ASD and 13 TD control participants while they watched animations involving two "interacting" geometrical shapes. Participants with ASD showed significantly reduced activation, relative to TD controls, in regions considered part of the ToM network, the mirror network, and the cerebellum. Functional connectivity analyses revealed underconnectivity between frontal and posterior regions during task performance in the ASD participants. Overall, the findings of this study reveal disruptions in the brain circuitry underlying ToM in ASD at multiple levels, including decreased activation and decreased functional connectivity.

  10. Information theory and signal transduction systems: from molecular information processing to network inference.

    Science.gov (United States)

    Mc Mahon, Siobhan S; Sim, Aaron; Filippi, Sarah; Johnson, Robert; Liepe, Juliane; Smith, Dominic; Stumpf, Michael P H

    2014-11-01

    Sensing and responding to the environment are two essential functions that all biological organisms need to master for survival and successful reproduction. Developmental processes are marshalled by a diverse set of signalling and control systems, ranging from systems with simple chemical inputs and outputs to complex molecular and cellular networks with non-linear dynamics. Information theory provides a powerful and convenient framework in which such systems can be studied; but it also provides the means to reconstruct the structure and dynamics of molecular interaction networks underlying physiological and developmental processes. Here we supply a brief description of its basic concepts and introduce some useful tools for systems and developmental biologists. Along with a brief but thorough theoretical primer, we demonstrate the wide applicability and biological application-specific nuances by way of different illustrative vignettes. In particular, we focus on the characterisation of biological information processing efficiency, examining cell-fate decision making processes, gene regulatory network reconstruction, and efficient signal transduction experimental design. Copyright © 2014 Elsevier Ltd. All rights reserved.

  11. Asymptotic Analysis of Large Cooperative Relay Networks Using Random Matrix Theory

    Directory of Open Access Journals (Sweden)

    H. Poor

    2008-04-01

    Full Text Available Cooperative transmission is an emerging communication technology that takes advantage of the broadcast nature of wireless channels. In cooperative transmission, the use of relays can create a virtual antenna array so that multiple-input/multiple-output (MIMO techniques can be employed. Most existing work in this area has focused on the situation in which there are a small number of sources and relays and a destination. In this paper, cooperative relay networks with large numbers of nodes are analyzed, and in particular the asymptotic performance improvement of cooperative transmission over direction transmission and relay transmission is analyzed using random matrix theory. The key idea is to investigate the eigenvalue distributions related to channel capacity and to analyze the moments of this distribution in large wireless networks. A performance upper bound is derived, the performance in the low signal-to-noise-ratio regime is analyzed, and two approximations are obtained for high and low relay-to-destination link qualities, respectively. Finally, simulations are provided to validate the accuracy of the analytical results. The analysis in this paper provides important tools for the understanding and the design of large cooperative wireless networks.

  12. Design of a universal two-layered neural network derived from the PLI theory

    Science.gov (United States)

    Hu, Chia-Lun J.

    2004-05-01

    The if-and-only-if (IFF) condition that a set of M analog-to-digital vector-mapping relations can be learned by a one-layered-feed-forward neural network (OLNN) is that all the input analog vectors dichotomized by the i-th output bit must be positively, linearly independent, or PLI. If they are not PLI, then the OLNN just cannot learn no matter what learning rules is employed because the solution of the connection matrix does not exist mathematically. However, in this case, one can still design a parallel-cascaded, two-layered, perceptron (PCTLP) to acheive this general mapping goal. The design principle of this "universal" neural network is derived from the major mathematical properties of the PLI theory - changing the output bits of the dependent relations existing among the dichotomized input vectors to make the PLD relations PLI. Then with a vector concatenation technique, the required mapping can still be learned by this PCTLP system with very high efficiency. This paper will report in detail the mathematical derivation of the general design principle and the design procedures of the PCTLP neural network system. It then will be verified in general by a practical numerical example.

  13. ‘Living' theory: a pedagogical framework for process support in networked learning

    Directory of Open Access Journals (Sweden)

    Philipa Levy

    2006-12-01

    Full Text Available This paper focuses on the broad outcome of an action research project in which practical theory was developed in the field of networked learning through case-study analysis of learners' experiences and critical evaluation of educational practice. It begins by briefly discussing the pedagogical approach adopted for the case-study course and the action research methodology. It then identifies key dimensions of four interconnected developmental processes–orientation, communication, socialisation and organisation–that were associated with ‘learning to learn' in the course's networked environment, and offers a flavour of participants' experiences in relation to these processes. A number of key evaluation issues that arose are highlighted. Finally, the paper presents the broad conceptual framework for the design and facilitation of process support in networked learning that was derived from this research. The framework proposes a strong, explicit focus on support for process as well as domain learning, and progression from tighter to looser design and facilitation structures for process-focused (as well as domain-focused learning tasks.

  14. A Game Theory-Based Obstacle Avoidance Routing Protocol for Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Shujun Bi

    2011-09-01

    Full Text Available The obstacle avoidance problem in geographic forwarding is an important issue for location-based routing in wireless sensor networks. The presence of an obstacle leads to several geographic routing problems such as excessive energy consumption and data congestion. Obstacles are hard to avoid in realistic environments. To bypass obstacles, most routing protocols tend to forward packets along the obstacle boundaries. This leads to a situation where the nodes at the boundaries exhaust their energy rapidly and the obstacle area is diffused. In this paper, we introduce a novel routing algorithm to solve the obstacle problem in wireless sensor networks based on a game-theory model. Our algorithm forms a concave region that cannot forward packets to achieve the aim of improving the transmission success rate and decreasing packet transmission delays. We consider the residual energy, out-degree and forwarding angle to determine the forwarding probability and payoff function of forwarding candidates. This achieves the aim of load balance and reduces network energy consumption. Simulation results show that based on the average delivery delay, energy consumption and packet delivery ratio performances our protocol is superior to other traditional schemes.

  15. Application of Percolation Theory to Complex Interconnected Networks in Advanced Functional Composites

    Science.gov (United States)

    Hing, P.

    2011-11-01

    Percolation theory deals with the behaviour of connected clusters in a system. Originally developed for studying the flow of liquid in a porous body, the percolation theory has been extended to quantum computation and communication, entanglement percolation in quantum networks, cosmology, chaotic situations, properties of disordered solids, pandemics, petroleum industry, finance, control of traffic and so on. In this paper, the application of various models of the percolation theory to predict and explain the properties of a specially developed family of dense sintered and highly refractory Al2O3-W composites for potential application in high intensity discharge light sources such as high pressure sodium lamps and ceramic metal halide lamps are presented and discussed. The low cost, core-shell concept can be extended to develop functional composite materials with unusual dielectric, electrical, magnetic, superconducting, and piezoelectric properties starting from a classical insulator. The core shell concept can also be applied to develop catalysts with high specific surface areas with minimal amount of expensive platinium, palladium or rare earth nano structured materials for light harvesting, replicating natural photosynthesis, in synthetic zeolite composites for the cracking and separation of crude oil. There is also possibility of developing micron and nanosize Faraday cages for quantum devices, nano electronics and spintronics. The possibilities are limitless.

  16. Pensar e intervenir el territorio a traves de la Teoria del Actor-Red

    Directory of Open Access Journals (Sweden)

    Juan E. Cabrera

    2011-03-01

    Full Text Available El propósito de este artículo es reflexionar sobre las coincidencias entre la forma de ver el territorio como red, algunas posturas teóricas sobre su concepto y la teoría del actor-red. Sobre lo anterior se centra en proponer una forma de entender las relaciones entre actores cuando se va a intervenir el territorio a través de políticas públicas como la planificación utilizando un modelo de gestión territorial a través de las orientaciones de la TAR.   

  17. The moral problem of worse actors

    Directory of Open Access Journals (Sweden)

    Scott Wisor

    2014-05-01

    Full Text Available Individuals and institutions sometimes have morally stringent reasons to not do a given action. For example, an oil company might have morally stringent reasons to refrain from providing revenue to a genocidal regime, or an engineer might have morally stringent reasons to refrain from providing her expertise in the development of weapons of mass destruction. But in some cases, if the agent does not do the action, another actor will do it with much worse consequences. For example, the oil company might know their assets will be bought by a company with worse environmental and labor practices. Or the engineer might know her position will be filled by a more ambitious and amoral engineer. I call this the moral problem of worse actors (MPWA. MPWA gives reason, at least some of the time, to consider otherwise morally impermissible actions permissible or even obligatory. On my account, doing the action in the circumstances of MPWA remains morally objectionable even if permissible or obligatory, and this brings additional moral responsibilities and obligations to the actor. Similarly, not doing the action in the circumstances of MPWA may also bring additional (but different moral responsibilities and obligations. Acknowledging MPWA creates considerable challenges, as many bad actors may appeal to it to justify morally objectionable action. In this paper, I develop a set of strategies for individuals and institutions to handle MPWA. This includes appeals to integrity and the proper attribution of expressive responsibility, regulatory responsibility, and compensatory responsibility. I also address a set of related concerns, including worries about incentivizing would-be bad actors, concerns about epistemic uncertainty, and the problem of mala in se exceptions.

  18. Book review: The success of policy analysis studies: an actor perspective, a search for success definitions based on cases in the field of transport and infrastructure in The Netherlands / by Patricia G.J. Twaalfhoven. - Eburon, Delft, 1999

    NARCIS (Netherlands)

    Klok, Pieter J.

    2001-01-01

    This doctoral dissertation is an attempt to formulate a theory on how different actors define the success of a policy analysis study and on the factors that underlie the various definitions of success. The choice for an actor perspective is motivated by the fact that many actors play different roles

  19. Quantitative design of emergency monitoring network for river chemical spills based on discrete entropy theory.

    Science.gov (United States)

    Shi, Bin; Jiang, Jiping; Sivakumar, Bellie; Zheng, Yi; Wang, Peng

    2018-05-01

    Field monitoring strategy is critical for disaster preparedness and watershed emergency environmental management. However, development of such is also highly challenging. Despite the efforts and progress thus far, no definitive guidelines or solutions are available worldwide for quantitatively designing a monitoring network in response to river chemical spill incidents, except general rules based on administrative divisions or arbitrary interpolation on routine monitoring sections. To address this gap, a novel framework for spatial-temporal network design was proposed in this study. The framework combines contaminant transport modelling with discrete entropy theory and spectral analysis. The water quality model was applied to forecast the spatio-temporal distribution of contaminant after spills and then corresponding information transfer indexes (ITIs) and Fourier approximation periodic functions were estimated as critical measures for setting sampling locations and times. The results indicate that the framework can produce scientific preparedness plans of emergency monitoring based on scenario analysis of spill risks as well as rapid design as soon as the incident happened but not prepared. The framework was applied to a hypothetical spill case based on tracer experiment and a real nitrobenzene spill incident case to demonstrate its suitability and effectiveness. The newly-designed temporal-spatial monitoring network captured major pollution information at relatively low costs. It showed obvious benefits for follow-up early-warning and treatment as well as for aftermath recovery and assessment. The underlying drivers of ITIs as well as the limitations and uncertainty of the approach were analyzed based on the case studies. Comparison with existing monitoring network design approaches, management implications, and generalized applicability were also discussed. Copyright © 2018 Elsevier Ltd. All rights reserved.

  20. Interactive Actor Analysis for Rural Water Management in The Netherlands : An Application of the Transactional Approach

    NARCIS (Netherlands)

    J.S. Timmermans (Jos)

    2009-01-01

    textabstractRecent developments in the policy sciences emphasize the social environment in which decisions are made. The ‘network metaphor’ is often used to describe the key role of interactions between interdependent actors involved in decision making. These interactions take place in a policy

  1. Exploring empowerment in settings: mapping distributions of network power.

    Science.gov (United States)

    Neal, Jennifer Watling

    2014-06-01

    This paper brings together two trends in the empowerment literature-understanding empowerment in settings and understanding empowerment as relational-by examining what makes settings empowering from a social network perspective. Specifically, extending Neal and Neal's (Am J Community Psychol 48(3/4):157-167, 2011) conception of network power, an empowering setting is defined as one in which (1) actors have existing relationships that allow for the exchange of resources and (2) the distribution of network power among actors in the setting is roughly equal. The paper includes a description of how researchers can examine distributions of network power in settings. Next, this process is illustrated in both an abstract example and using empirical data on early adolescents' peer relationships in urban classrooms. Finally, implications for theory, methods, and intervention related to understanding empowering settings are explored.

  2. An Anatomy of Authority: The Bologna and ASEM Education Secretariats as Policy Actors and Region Builders

    Science.gov (United States)

    Dang, Que Anh

    2018-01-01

    This paper examines the sources of authority behind the Bologna and ASEM secretariats' technocratic appearance and administrative routines, and argues that they are transnational policy actors in their own right. By drawing on principal-agent theory and the concept of "authority," it offers an alternative framework for understanding the…

  3. A Critical Copenhagen Reflection on the European Union as a Global Actor

    DEFF Research Database (Denmark)

    Manners, Ian James

    2016-01-01

    a Copenhagen reflection on the EU as a global actor within the context of the Normative Power Approach (NPA). The chapter engages in a critical Copenhagen reflection, which means that it takes seriously the insights of critical social theory and the role of cultural hegemony. The chapter argues that the NPA...

  4. Learning Science in a Virtual Reality Application: The Impacts of Animated-Virtual Actors' Visual Complexity

    Science.gov (United States)

    Kartiko, Iwan; Kavakli, Manolya; Cheng, Ken

    2010-01-01

    As the technology in computer graphics advances, Animated-Virtual Actors (AVAs) in Virtual Reality (VR) applications become increasingly rich and complex. Cognitive Theory of Multimedia Learning (CTML) suggests that complex visual materials could hinder novice learners from attending to the lesson properly. On the other hand, previous studies have…

  5. Software Defined Network Monitoring Scheme Using Spectral Graph Theory and Phantom Nodes

    Science.gov (United States)

    2014-09-01

    networks is the emergence of software - defined networking ( SDN ) [1]. SDN has existed for the...Chapter III for network monitoring. A. SOFTWARE DEFINED NETWORKS SDNs provide a new and innovative method to simplify network hardware by logically...and R. Giladi, “Performance analysis of software - defined networking ( SDN ),” in Proc. of IEEE 21st International Symposium on Modeling, Analysis

  6. STICAP: A linear circuit analysis program with stiff systems capability. Volume 1: Theory manual. [network analysis

    Science.gov (United States)

    Cooke, C. H.

    1975-01-01

    STICAP (Stiff Circuit Analysis Program) is a FORTRAN 4 computer program written for the CDC-6400-6600 computer series and SCOPE 3.0 operating system. It provides the circuit analyst a tool for automatically computing the transient responses and frequency responses of large linear time invariant networks, both stiff and nonstiff (algorithms and numerical integration techniques are described). The circuit description and user's program input language is engineer-oriented, making simple the task of using the program. Engineering theories underlying STICAP are examined. A user's manual is included which explains user interaction with the program and gives results of typical circuit design applications. Also, the program structure from a systems programmer's viewpoint is depicted and flow charts and other software documentation are given.

  7. Investigation on law and economics of listed companies' financing preference based on complex network theory.

    Directory of Open Access Journals (Sweden)

    Jian Yang

    Full Text Available In this paper, complex network theory is used to make time-series analysis of key indicators of governance structure and financing data. We analyze scientific listed companies' governance data from 2010 to 2014 and divide them into groups in accordance with the similarity they share. Then we select sample companies to analyze their financing data and explore the influence of governance structure on financing decision and the financing preference they display. This paper reviews relevant laws and regulations of financing from the perspective of law and economics, then proposes reasonable suggestions to consummate the law for the purpose of regulating listed companies' financing. The research provides a reference for making qualitative analysis on companies' financing.

  8. Improving the accuracy of Møller-Plesset perturbation theory with neural networks

    Science.gov (United States)

    McGibbon, Robert T.; Taube, Andrew G.; Donchev, Alexander G.; Siva, Karthik; Hernández, Felipe; Hargus, Cory; Law, Ka-Hei; Klepeis, John L.; Shaw, David E.

    2017-10-01

    Noncovalent interactions are of fundamental importance across the disciplines of chemistry, materials science, and biology. Quantum chemical calculations on noncovalently bound complexes, which allow for the quantification of properties such as binding energies and geometries, play an essential role in advancing our understanding of, and building models for, a vast array of complex processes involving molecular association or self-assembly. Because of its relatively modest computational cost, second-order Møller-Plesset perturbation (MP2) theory is one of the most widely used methods in quantum chemistry for studying noncovalent interactions. MP2 is, however, plagued by serious errors due to its incomplete treatment of electron correlation, especially when modeling van der Waals interactions and π-stacked complexes. Here we present spin-network-scaled MP2 (SNS-MP2), a new semi-empirical MP2-based method for dimer interaction-energy calculations. To correct for errors in MP2, SNS-MP2 uses quantum chemical features of the complex under study in conjunction with a neural network to reweight terms appearing in the total MP2 interaction energy. The method has been trained on a new data set consisting of over 200 000 complete basis set (CBS)-extrapolated coupled-cluster interaction energies, which are considered the gold standard for chemical accuracy. SNS-MP2 predicts gold-standard binding energies of unseen test compounds with a mean absolute error of 0.04 kcal mol-1 (root-mean-square error 0.09 kcal mol-1), a 6- to 7-fold improvement over MP2. To the best of our knowledge, its accuracy exceeds that of all extant density functional theory- and wavefunction-based methods of similar computational cost, and is very close to the intrinsic accuracy of our benchmark coupled-cluster methodology itself. Furthermore, SNS-MP2 provides reliable per-conformation confidence intervals on the predicted interaction energies, a feature not available from any alternative method.

  9. MODEL OF REGIONAL KNOWLEDGE TRANSFER: MAIN ACTORS, FRAMEWORK AND THEORY.

    Directory of Open Access Journals (Sweden)

    Alla LEVITSKAIA

    2016-02-01

    Full Text Available This paper analyses potential mechanism of regional knowledge transfer in region with poorly developed innovation infrastructure (the Autonomous Territorial Unit Gagauzia, Republic of Moldova through interactions between regional major players of the Regional Innovation System - the educational and research institutions, small and medium enterprises (SMEs and local authorities. Solution of this problem can be found in modern studies of territories innovation development through the clustering processes. Through the empirical study - innovation potential analysis of local SMEs - we proposed advantage mechanism which focused on the one type of knowledge cluster – Innovation and Educational Cluster. The symbiosis of entrepreneurs, government agencies, educational institutions and business service providers with the regional core - University, allows to increasing exchange flows of innovative knowledge between all members of the cluster and distributing them to the entire region and beyond. The results and proposals of this study formed the basis of the “Program of increasing the innovation potential of Gagauz SMEs”.

  10. How network-based incubation helps start-up performance : a systematic review against the background of management theories

    OpenAIRE

    Eveleens, Chris P.; van Rijnsoever, Frank J.; Niesten, Eva M M I

    2017-01-01

    The literature on how network-based incubation influences the performance of technology-based start-ups has recently grown considerably and provided valuable insights. However, at the same time this literature has become quite fragmented, inconsistently conceptualised, and theoretically underdeveloped. Therefore, this article uses three management theories to structure the literature, improve the theoretical underpinning and develop an agenda for further research. The management theories are ...

  11. Technology strategy as macro-actor

    DEFF Research Database (Denmark)

    Tryggestad, Kjell

    2003-01-01

    -human entities to the explanatory repertoire of strategy research, another line of inquiry is pursued. The performative perspective thus proposed, is inspired by the classical work of Von Clausewitz and the recent anthropology of science, technology and organizational identities. In the proposed perspective...... case account for how the strategic technology and the strategic collective emerge and co-produce each other as a macro-actor, only to become transformed in unexpected ways - as common technology and reflective human subjects.In the concluding section, it is argued that the humanity of the reflective...... outcomes, as providers of explanations and observations. The expression `technological strategy as macro-actor' summarizes these findings and the associated implications for research and practice....

  12. African Initiated Churches’ potential as development actors

    Directory of Open Access Journals (Sweden)

    Philipp Öhlmann

    2016-11-01

    Full Text Available African Initiated Churches (AICs are not yet recognised as relevant actors of community development interventions. While it has been acknowledged that many of them provide coping mechanisms in adverse environments, support in social transformation and social capital, little information is available on their role as development actors. In this article, we evaluate the potential of AICs as partners of international development agencies for community development. We draw on interviews and focus group discussions with leaders of various AICs conducted in South Africa in February and March 2016. In particular, we examine the churches’ understanding of development, their view on the separation of spiritual and development activities and their priorities. Moreover, we outline the development activities which they are currently engaged in and analyse the structures they have in place to do so. Our findings indicate that AICs are increasingly active in community development and offer various entry points for possible cooperation.

  13. Load reduction test method of similarity theory and BP neural networks of large cranes

    Science.gov (United States)

    Yang, Ruigang; Duan, Zhibin; Lu, Yi; Wang, Lei; Xu, Gening

    2016-01-01

    Static load tests are an important means of supervising and detecting a crane's lift capacity. Due to space restrictions, however, there are difficulties and potential danger when testing large bridge cranes. To solve the loading problems of large-tonnage cranes during testing, an equivalency test is proposed based on the similarity theory and BP neural networks. The maximum stress and displacement of a large bridge crane is tested in small loads, combined with the training neural network of a similar structure crane through stress and displacement data which is collected by a physics simulation progressively loaded to a static load test load within the material scope of work. The maximum stress and displacement of a crane under a static load test load can be predicted through the relationship of stress, displacement, and load. By measuring the stress and displacement of small tonnage weights, the stress and displacement of large loads can be predicted, such as the maximum load capacity, which is 1.25 times the rated capacity. Experimental study shows that the load reduction test method can reflect the lift capacity of large bridge cranes. The load shedding predictive analysis for Sanxia 1200 t bridge crane test data indicates that when the load is 1.25 times the rated lifting capacity, the predicted displacement and actual displacement error is zero. The method solves the problem that lifting capacities are difficult to obtain and testing accidents are easily possible when 1.25 times related weight loads are tested for large tonnage cranes.

  14. Combining a dispersal model with network theory to assess habitat connectivity.

    Science.gov (United States)

    Lookingbill, Todd R; Gardner, Robert H; Ferrari, Joseph R; Keller, Cherry E

    2010-03-01

    Assessing the potential for threatened species to persist and spread within fragmented landscapes requires the identification of core areas that can sustain resident populations and dispersal corridors that can link these core areas with isolated patches of remnant habitat. We developed a set of GIS tools, simulation methods, and network analysis procedures to assess potential landscape connectivity for the Delmarva fox squirrel (DFS; Sciurus niger cinereus), an endangered species inhabiting forested areas on the Delmarva Peninsula, USA. Information on the DFS's life history and dispersal characteristics, together with data on the composition and configuration of land cover on the peninsula, were used as input data for an individual-based model to simulate dispersal patterns of millions of squirrels. Simulation results were then assessed using methods from graph theory, which quantifies habitat attributes associated with local and global connectivity. Several bottlenecks to dispersal were identified that were not apparent from simple distance-based metrics, highlighting specific locations for landscape conservation, restoration, and/or squirrel translocations. Our approach links simulation models, network analysis, and available field data in an efficient and general manner, making these methods useful and appropriate for assessing the movement dynamics of threatened species within landscapes being altered by human and natural disturbances.

  15. Dynamical assessment for evolutions of Atomic-Multinology (AM) in technology innovation using social network theory

    International Nuclear Information System (INIS)

    Woo, Taeho

    2012-01-01

    Highlights: ► The popularity of AM is analyzed by the social network theory. ► The graphical and colorful configurations are used for the meaning of the incident. ► The new industrial field is quantified by dynamical investigations. ► AM can be successfully used in nuclear industry for technology innovation. ► The method could be used for other industries. - Abstract: The technology evolution is investigated. The proposed Atomic Multinology (AM) is quantified by the dynamical method incorporated with Monte-Carlo method. There are three kinds of the technologies as the info-technology (IT), nano-technology (NT), and bio-technology (BT), which are applied to the nuclear technology. AM is initiated and modeled for the dynamic quantifications. The social network algorithm is used in the dynamical simulation for the management of the projects. The result shows that the successfulness of the AM increases, where the 60 years are the investigated period. The values of the dynamical simulation increase in later stage, which means that the technology is matured as time goes on.

  16. Game Theory Based Security in Wireless Body Area Network with Stackelberg Security Equilibrium.

    Science.gov (United States)

    Somasundaram, M; Sivakumar, R

    2015-01-01

    Wireless Body Area Network (WBAN) is effectively used in healthcare to increase the value of the patient's life and also the value of healthcare services. The biosensor based approach in medical care system makes it difficult to respond to the patients with minimal response time. The medical care unit does not deploy the accessing of ubiquitous broadband connections full time and hence the level of security will not be high always. The security issue also arises in monitoring the user body function records. Most of the systems on the Wireless Body Area Network are not effective in facing the security deployment issues. To access the patient's information with higher security on WBAN, Game Theory with Stackelberg Security Equilibrium (GTSSE) is proposed in this paper. GTSSE mechanism takes all the players into account. The patients are monitored by placing the power position authority initially. The position authority in GTSSE is the organizer and all the other players react to the organizer decision. Based on our proposed approach, experiment has been conducted on factors such as security ratio based on patient's health information, system flexibility level, energy consumption rate, and information loss rate. Stackelberg Security considerably improves the strength of solution with higher security.

  17. Implementation of Solid Waste Policies in Pernambuco: a study from the institutional theory and interorganizational networks

    Directory of Open Access Journals (Sweden)

    Maria Luciana de Almeida

    2015-09-01

    Full Text Available Solid waste is a problem in the Brazilian context, not only because it is growing in larger proportions than the population and leading to soil and water contamination, but also because it is a vector for diseases and causes economic losses, since much of what is discarded can be reused. After several years of intense debate, the Brazilian law applying to national solid waste policy was sanctioned; this law contains goals to be achieved and challenges to be overcome. Since this is a major issue, the purpose of this paper is to discuss the implementation of public policies on solid waste, emphasizing the initiatives carried out in the state of Pernambuco, from the perspectives of institutional theory and inter-organizational networks. By analysing the provisions of the law, we can observe a coercive tendency to bring the states and municipalities to establish networks in order to meet demands related to solid waste, since the pertinent legislation induces the involved entities to develop this kind of partnership in order to obtain resources

  18. Game Theory Based Security in Wireless Body Area Network with Stackelberg Security Equilibrium

    Science.gov (United States)

    Somasundaram, M.; Sivakumar, R.

    2015-01-01

    Wireless Body Area Network (WBAN) is effectively used in healthcare to increase the value of the patient's life and also the value of healthcare services. The biosensor based approach in medical care system makes it difficult to respond to the patients with minimal response time. The medical care unit does not deploy the accessing of ubiquitous broadband connections full time and hence the level of security will not be high always. The security issue also arises in monitoring the user body function records. Most of the systems on the Wireless Body Area Network are not effective in facing the security deployment issues. To access the patient's information with higher security on WBAN, Game Theory with Stackelberg Security Equilibrium (GTSSE) is proposed in this paper. GTSSE mechanism takes all the players into account. The patients are monitored by placing the power position authority initially. The position authority in GTSSE is the organizer and all the other players react to the organizer decision. Based on our proposed approach, experiment has been conducted on factors such as security ratio based on patient's health information, system flexibility level, energy consumption rate, and information loss rate. Stackelberg Security considerably improves the strength of solution with higher security. PMID:26759829

  19. Understanding Health Information Seeking from an Actor-Centric Perspective

    Directory of Open Access Journals (Sweden)

    Simon Batchelor

    2015-07-01

    Full Text Available This paper presents a conceptual approach for discussing health information seeking among poor households in Africa and Asia. This approach is part of a larger research endeavor aimed at understanding how health systems are adapting; with possibilities and constraints emerging. These health systems can be found in a context of the changing relationships between states, markets and civil society in low and middle income countries. The paper starts from an understanding of the health sector as a “health knowledge economy”, organized to provide people with access to knowledge and advice. The use of the term “health knowledge economy” draws attention to the ways the health sector is part of a broader knowledge economy changing the way individuals and households obtain and use specialist information. The paper integrates an actor centric approach with the theory of planned behavior. It seeks to identify the actors engaged in the health knowledge economy as a precursor to longer term studies on the uptake of innovations integrating health services with mobile phones, commonly designated as mHealth, contributing to an understanding of the potential vulnerabilities of poor people, and highlighting possible dangers if providers of health information and advice are strongly influenced by interest groups.

  20. Practical application of game theory based production flow planning method in virtual manufacturing networks

    Science.gov (United States)

    Olender, M.; Krenczyk, D.

    2016-08-01

    Modern enterprises have to react quickly to dynamic changes in the market, due to changing customer requirements and expectations. One of the key area of production management, that must continuously evolve by searching for new methods and tools for increasing the efficiency of manufacturing systems is the area of production flow planning and control. These aspects are closely connected with the ability to implement the concept of Virtual Enterprises (VE) and Virtual Manufacturing Network (VMN) in which integrated infrastructure of flexible resources are created. In the proposed approach, the players role perform the objects associated with the objective functions, allowing to solve the multiobjective production flow planning problems based on the game theory, which is based on the theory of the strategic situation. For defined production system and production order models ways of solving the problem of production route planning in VMN on computational examples for different variants of production flow is presented. Possible decision strategy to use together with an analysis of calculation results is shown.