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Sample records for network capsnet collects

  1. The Canadian Pediatric Surgery Network (CAPSNet): Lessons Learned from a National Registry Devoted to the Study of Congenital Diaphragmatic Hernia and Gastroschisis.

    Science.gov (United States)

    Butler, Alison E; Puligandla, Pramod S; Skarsgard, Erik D

    2015-12-01

    The Canadian Pediatric Surgery Network (CAPSNet) was created in 2005 by a geographically representative, multidisciplinary group of clinicians and researchers with the intent of establishing a national research registry for gastroschisis (GS) and congenital diaphragmatic hernia (CDH). Since then, CAPSNet has used this registry and its 16-center network to make contributions to the knowledge base informing best practices for GS and CDH care. More recently, CAPSNet has expanded its focus to include quality assurance and improvement at each of its sites, by issuing a benchmarked outcomes "report card" with its annual report. Finally, a major objective of CAPSNet has been to establish and adopt standardized, evidence-based practice guidelines for GS and CDH across all Canadian perinatal centers. Georg Thieme Verlag KG Stuttgart · New York.

  2. Collective network routing

    Science.gov (United States)

    Hoenicke, Dirk

    2014-12-02

    Disclosed are a unified method and apparatus to classify, route, and process injected data packets into a network so as to belong to a plurality of logical networks, each implementing a specific flow of data on top of a common physical network. The method allows to locally identify collectives of packets for local processing, such as the computation of the sum, difference, maximum, minimum, or other logical operations among the identified packet collective. Packets are injected together with a class-attribute and an opcode attribute. Network routers, employing the described method, use the packet attributes to look-up the class-specific route information from a local route table, which contains the local incoming and outgoing directions as part of the specifically implemented global data flow of the particular virtual network.

  3. Collective network for computer structures

    Science.gov (United States)

    Blumrich, Matthias A [Ridgefield, CT; Coteus, Paul W [Yorktown Heights, NY; Chen, Dong [Croton On Hudson, NY; Gara, Alan [Mount Kisco, NY; Giampapa, Mark E [Irvington, NY; Heidelberger, Philip [Cortlandt Manor, NY; Hoenicke, Dirk [Ossining, NY; Takken, Todd E [Brewster, NY; Steinmacher-Burow, Burkhard D [Wernau, DE; Vranas, Pavlos M [Bedford Hills, NY

    2011-08-16

    A system and method for enabling high-speed, low-latency global collective communications among interconnected processing nodes. The global collective network optimally enables collective reduction operations to be performed during parallel algorithm operations executing in a computer structure having a plurality of the interconnected processing nodes. Router devices ate included that interconnect the nodes of the network via links to facilitate performance of low-latency global processing operations at nodes of the virtual network and class structures. The global collective network may be configured to provide global barrier and interrupt functionality in asynchronous or synchronized manner. When implemented in a massively-parallel supercomputing structure, the global collective network is physically and logically partitionable according to needs of a processing algorithm.

  4. Collective intelligent wireless sensor networks

    NARCIS (Netherlands)

    Mihaylov, M.; Nowe, A.; Tuyls, K.P.; Nijholt, A.; Pantic, M.

    2008-01-01

    In this paper we apply the COllective INtelligence (COIN) framework ofWolpert et al. toWireless Sensor Networks (WSNs) with the aim to increase the autonomous lifetime of the network in a decentralized manner. COIN describes how selfish agents can learn to optimize their own performance, so that the

  5. Control of collective network chaos.

    Science.gov (United States)

    Wagemakers, Alexandre; Barreto, Ernest; Sanjuán, Miguel A F; So, Paul

    2014-06-01

    Under certain conditions, the collective behavior of a large globally-coupled heterogeneous network of coupled oscillators, as quantified by the macroscopic mean field or order parameter, can exhibit low-dimensional chaotic behavior. Recent advances describe how a small set of "reduced" ordinary differential equations can be derived that captures this mean field behavior. Here, we show that chaos control algorithms designed using the reduced equations can be successfully applied to imperfect realizations of the full network. To systematically study the effectiveness of this technique, we measure the quality of control as we relax conditions that are required for the strict accuracy of the reduced equations, and hence, the controller. Although the effects are network-dependent, we show that the method is effective for surprisingly small networks, for modest departures from global coupling, and even with mild inaccuracy in the estimate of network heterogeneity.

  6. Collective Classification in Network Data

    OpenAIRE

    Sen, Prithviraj; Namata, Galileo; Bilgic, Mustafa; Getoor, Lise; University of Maryland; Galligher, Brian; Eliassi-Rad, Tina

    2008-01-01

    Many real-world applications produce networked data such as the world-wide web (hypertext documents connected via hyperlinks), social networks (for example, people connected by friendship links), communication networks (computers connected via communication links) and biological networks (for example, protein interaction networks). A recent focus in machine learning research has been to extend traditional machine learning classification techniques to classify nodes in such networks. In this a...

  7. Collective fluctuations in networks of noisy components

    International Nuclear Information System (INIS)

    Masuda, Naoki; Kawamura, Yoji; Kori, Hiroshi

    2010-01-01

    Collective dynamics result from interactions among noisy dynamical components. Examples include heartbeats, circadian rhythms and various pattern formations. Because of noise in each component, collective dynamics inevitably involve fluctuations, which may crucially affect the functioning of the system. However, the relation between the fluctuations in isolated individual components and those in collective dynamics is not clear. Here, we study a linear dynamical system of networked components subjected to independent Gaussian noise and analytically show that the connectivity of networks determines the intensity of fluctuations in the collective dynamics. Remarkably, in general directed networks including scale-free networks, the fluctuations decrease more slowly with system size than the standard law stated by the central limit theorem. They even remain finite for a large system size when global directionality of the network exists. Moreover, such non-trivial behavior appears even in undirected networks when nonlinear dynamical systems are considered. We demonstrate it with a coupled oscillator system.

  8. Global action networks: agents for collective action

    NARCIS (Netherlands)

    Glasbergen, P.

    2010-01-01

    Global action networks (GANs) are civil society initiated multi-stakeholder arrangements that aim to fulfill a leadership role for systemic change in global governance for sustainable development. The paper develops a network approach to study some of these GANs as motivators of global collective

  9. Adaptive-network models of collective dynamics

    Science.gov (United States)

    Zschaler, G.

    2012-09-01

    Complex systems can often be modelled as networks, in which their basic units are represented by abstract nodes and the interactions among them by abstract links. This network of interactions is the key to understanding emergent collective phenomena in such systems. In most cases, it is an adaptive network, which is defined by a feedback loop between the local dynamics of the individual units and the dynamical changes of the network structure itself. This feedback loop gives rise to many novel phenomena. Adaptive networks are a promising concept for the investigation of collective phenomena in different systems. However, they also present a challenge to existing modelling approaches and analytical descriptions due to the tight coupling between local and topological degrees of freedom. In this work, which is essentially my PhD thesis, I present a simple rule-based framework for the investigation of adaptive networks, using which a wide range of collective phenomena can be modelled and analysed from a common perspective. In this framework, a microscopic model is defined by the local interaction rules of small network motifs, which can be implemented in stochastic simulations straightforwardly. Moreover, an approximate emergent-level description in terms of macroscopic variables can be derived from the microscopic rules, which we use to analyse the system's collective and long-term behaviour by applying tools from dynamical systems theory. We discuss three adaptive-network models for different collective phenomena within our common framework. First, we propose a novel approach to collective motion in insect swarms, in which we consider the insects' adaptive interaction network instead of explicitly tracking their positions and velocities. We capture the experimentally observed onset of collective motion qualitatively in terms of a bifurcation in this non-spatial model. We find that three-body interactions are an essential ingredient for collective motion to emerge

  10. Collective stochastic coherence in recurrent neuronal networks

    Science.gov (United States)

    Sancristóbal, Belén; Rebollo, Beatriz; Boada, Pol; Sanchez-Vives, Maria V.; Garcia-Ojalvo, Jordi

    2016-09-01

    Recurrent networks of dynamic elements frequently exhibit emergent collective oscillations, which can show substantial regularity even when the individual elements are considerably noisy. How noise-induced dynamics at the local level coexists with regular oscillations at the global level is still unclear. Here we show that a combination of stochastic recurrence-based initiation with deterministic refractoriness in an excitable network can reconcile these two features, leading to maximum collective coherence for an intermediate noise level. We report this behaviour in the slow oscillation regime exhibited by a cerebral cortex network under dynamical conditions resembling slow-wave sleep and anaesthesia. Computational analysis of a biologically realistic network model reveals that an intermediate level of background noise leads to quasi-regular dynamics. We verify this prediction experimentally in cortical slices subject to varying amounts of extracellular potassium, which modulates neuronal excitability and thus synaptic noise. The model also predicts that this effectively regular state should exhibit noise-induced memory of the spatial propagation profile of the collective oscillations, which is also verified experimentally. Taken together, these results allow us to construe the high regularity observed experimentally in the brain as an instance of collective stochastic coherence.

  11. Collective Dynamics in Physical and Social Networks

    Science.gov (United States)

    Isakov, Alexander

    We study four systems where individual units come together to display a range of collective behavior. First, we consider a physical system of phase oscillators on a network that expands the Kuramoto model to include oscillator-network interactions and the presence of noise: using a Hebbian-like learning rule, oscillators that synchronize in turn strengthen their connections to each other. We find that the average degree of connectivity strongly affects rates of flipping between aligned and anti-aligned states, and that this result persists to the case of complex networks. Turning to a fully multi-player, multi-strategy evolutionary dynamics model of cooperating bacteria that change who they give resources to and take resources from, we find several regimes that give rise to high levels of collective structure in the resulting networks. In this setting, we also explore the conditions in which an intervention that affects cooperation itself (e.g. "seeding the network with defectors") can lead to wiping out an infection. We find a non-monotonic connection between the percent of disabled cooperation and cure rate, suggesting that in some regimes a limited perturbation can lead to total population collapse. At a larger scale, we study how the locomotor system recovers after amputation in fruit flies. Through experiment and a theoretical model of multi-legged motion controlled by neural oscillators, we find that proprioception plays a role in the ability of flies to control leg forces appropriately to recover from a large initial turning bias induced by the injury. Finally, at the human scale, we consider a social network in a traditional society in Africa to understand how social ties lead to group formation for collective action (stealth raids). We identify critical and distinct roles for both leadership (important for catalyzing a group) and friendship (important for final composition). We conclude with prospects for future work.

  12. Planning logistics network for recyclables collection

    Directory of Open Access Journals (Sweden)

    Ratković Branislava

    2014-01-01

    Full Text Available Rapid urbanization, intensified industrialization, rise of income, and a more sophisticated form of consumerism are leading to an increase in the amount and toxicity of waste all over the world. Whether reused, recycled, incinerated or put into landfill sites, the management of household and industrial waste yield financial and environmental costs. This paper presents a modeling approach that can be used for designing one part of recycling logistics network through defining optimal locations of collection points, and possible optimal scheduling of vehicles for collecting recyclables. [Projekat Ministarstva nauke Republike Srbije, br. TR36005

  13. Forecasting Zakat collection using artificial neural network

    Science.gov (United States)

    Sy Ahmad Ubaidillah, Sh. Hafizah; Sallehuddin, Roselina

    2013-04-01

    'Zakat', "that which purifies" or "alms", is the giving of a fixed portion of one's wealth to charity, generally to the poor and needy. It is one of the five pillars of Islam, and must be paid by all practicing Muslims who have the financial means (nisab). 'Nisab' is the minimum level to determine whether there is a 'zakat' to be paid on the assets. Today, in most Muslim countries, 'zakat' is collected through a decentralized and voluntary system. Under this voluntary system, 'zakat' committees are established, which are tasked with the collection and distribution of 'zakat' funds. 'Zakat' promotes a more equitable redistribution of wealth, and fosters a sense of solidarity amongst members of the 'Ummah'. The Malaysian government has established a 'zakat' center at every state to facilitate the management of 'zakat'. The center has to have a good 'zakat' management system to effectively execute its functions especially in the collection and distribution of 'zakat'. Therefore, a good forecasting model is needed. The purpose of this study is to develop a forecasting model for Pusat Zakat Pahang (PZP) to predict the total amount of collection from 'zakat' of assets more precisely. In this study, two different Artificial Neural Network (ANN) models using two different learning algorithms are developed; Back Propagation (BP) and Levenberg-Marquardt (LM). Both models are developed and compared in terms of their accuracy performance. The best model is determined based on the lowest mean square error and the highest correlations values. Based on the results obtained from the study, BP neural network is recommended as the forecasting model to forecast the collection from 'zakat' of assets for PZP.

  14. Collective iteration behavior for online social networks

    Science.gov (United States)

    Liu, Jian-Guo; Li, Ren-De; Guo, Qiang; Zhang, Yi-Cheng

    2018-06-01

    Understanding the patterns of collective behavior in online social network (OSNs) is critical to expanding the knowledge of human behavior and tie relationship. In this paper, we investigate a specific pattern called social signature in Facebook and Wiki users' online communication behaviors, capturing the distribution of frequency of interactions between different alters over time in the ego network. The empirical results show that there are robust social signatures of interactions no matter how friends change over time, which indicates that a stable commutation pattern exists in online communication. By comparing a random null model, we find the that commutation pattern is heterogeneous between ego and alters. Furthermore, in order to regenerate the pattern of the social signature, we present a preferential interaction model, which assumes that new users intend to look for the old users with strong ties while old users have tendency to interact with new friends. The experimental results show that the presented model can reproduce the heterogeneity of social signature by adjusting 2 parameters, the number of communicating targets m and the max number of interactions n, for Facebook users, m = n = 5, for Wiki users, m = 2 and n = 8. This work helps in deeply understanding the regularity of social signature.

  15. Collective almost synchronisation in complex networks.

    Science.gov (United States)

    Baptista, Murilo S; Ren, Hai-Peng; Swarts, Johen C M; Carareto, Rodrigo; Nijmeijer, Henk; Grebogi, Celso

    2012-01-01

    This work introduces the phenomenon of Collective Almost Synchronisation (CAS), which describes a universal way of how patterns can appear in complex networks for small coupling strengths. The CAS phenomenon appears due to the existence of an approximately constant local mean field and is characterised by having nodes with trajectories evolving around periodic stable orbits. Common notion based on statistical knowledge would lead one to interpret the appearance of a local constant mean field as a consequence of the fact that the behaviour of each node is not correlated to the behaviours of the others. Contrary to this common notion, we show that various well known weaker forms of synchronisation (almost, time-lag, phase synchronisation, and generalised synchronisation) appear as a result of the onset of an almost constant local mean field. If the memory is formed in a brain by minimising the coupling strength among neurons and maximising the number of possible patterns, then the CAS phenomenon is a plausible explanation for it.

  16. Optimal stabilization of Boolean networks through collective influence

    Science.gov (United States)

    Wang, Jiannan; Pei, Sen; Wei, Wei; Feng, Xiangnan; Zheng, Zhiming

    2018-03-01

    Boolean networks have attracted much attention due to their wide applications in describing dynamics of biological systems. During past decades, much effort has been invested in unveiling how network structure and update rules affect the stability of Boolean networks. In this paper, we aim to identify and control a minimal set of influential nodes that is capable of stabilizing an unstable Boolean network. For locally treelike Boolean networks with biased truth tables, we propose a greedy algorithm to identify influential nodes in Boolean networks by minimizing the largest eigenvalue of a modified nonbacktracking matrix. We test the performance of the proposed collective influence algorithm on four different networks. Results show that the collective influence algorithm can stabilize each network with a smaller set of nodes compared with other heuristic algorithms. Our work provides a new insight into the mechanism that determines the stability of Boolean networks, which may find applications in identifying virulence genes that lead to serious diseases.

  17. Collective Learning in Games through Social Networks

    NARCIS (Netherlands)

    Kosterman, S.; Gierasimczuk, N.; Armentano, M.G.; Monteserin, A.; Tang, J.; Yannibelli, V.

    2015-01-01

    This paper argues that combining social networks communication and games can positively influence the learning behavior of players. We propose a computational model that combines features of social network learning (communication) and game-based learning (strategy reinforcement). The focus is on

  18. Collective Travel Planning in Spatial Networks

    KAUST Repository

    Shang, Shuo; Chen, Lisi; Wei, Zhewei; Jensen, Christian S.; Wen, Ji-Rong; Kalnis, Panos

    2017-01-01

    We propose and investigate a novel query, the Collective Travel Planning (CTP) query, that finds the lowest-cost route connecting multiple query sources and a destination via at most k meeting points. This type of query is useful in organizing large

  19. Integrating Information Networks for Collective Planetary Stewardship

    Science.gov (United States)

    Tiwari, A.

    2016-12-01

    Responsible behaviour resulting from climate literacy in global environmental movement is limited to policy and planning institutions in the Global South, while remaining absent for ends-user. Thus, planetary stewardship exists only at earth system boundaries where pressures sink to the local scale while ethics remains afloat. Existing citizen participation is restricted within policy spheres, appearing synonymous to enforcements in social psychology. Much, accounted reason is that existing information mechanisms operate mostly through linear exchanges between institutions and users, therefore reinforcing only hierarchical relationships. This study discloses such relationships that contribute to broad networking gaps through information demand assessment of stakeholders in a dozen development projects based in South Asia. Two parameters widely used for this purpose are: a. Feedback: Ends-user feedback to improve consumption literacy of climate sensitive resources (through consumption displays, billing, advisory services ecolabelling, sensors) and, b. Institutional Policy: Rewarding punishing to enforce desired behaviour (subsidies, taxation). Research answered: 1. Who gets the information (Equity in Information Distribution)? As existing information publishing mechanisms are designed by and for analysts, 2. How information translates to climate action Transparency of Execution)? Findings suggested that climate goals manifested in economic policy, than environmental policy, have potential clear short-term benefits and costs, and coincide with people's economic goals Also grassroots roles for responsible behaviour are empowered with presence of end user information. Barier free climate communication process and decision making is ensured among multiplicity of stakeholders with often conflicting perspectives. Research finds significance where collaboration among information networks can better translate regional policies into local action for climate adaptation and

  20. Collective Travel Planning in Spatial Networks

    KAUST Repository

    Shang, Shuo

    2017-05-18

    We propose and investigate a novel query, the Collective Travel Planning (CTP) query, that finds the lowest-cost route connecting multiple query sources and a destination via at most k meeting points. This type of query is useful in organizing large events, and it can bring significant benefits to society and the environment: it can help optimize the allocation of transportation resources, reduce resource consumption, and enable smarter and greener transportation; and it can help reduce greenhouse-gas emissions and traffic congestion.

  1. Data Collection using Miniature Aerial Vehicles in Wireless Sensor Networks

    DEFF Research Database (Denmark)

    Mathur, Prateek; Nielsen, Rasmus Hjorth; Prasad, Neeli R.

    2016-01-01

    Energy constraints of sensor nodes in wireless sensor networks (WSNs) is a major challenge and minimising the overall data transmitted across a network using data aggregation, distributed source coding, and compressive sensing have been proposed as mechanisms for energy saving. Similarly, use...... of mobile nodes capable of relocating within the network has been widely explored for energy saving. In this paper, we propose a novel method for using miniature aerial vehicles (MAVs) for data collection instead of actively sensing from a deployed network. The proposed mechanism is referred as Data...

  2. Collective Travel Planning in Spatial Networks

    KAUST Repository

    Shang, Shuo

    2015-12-17

    Travel planning and recommendation are important aspects of transportation.We propose and investigate a novel Collective Travel Planning (CTP) query that finds the lowest-cost route connecting multiple sources and a destination, via at most k meeting points. When multiple travelers target the same destination (e.g., a stadium or a theater), they may want to assemble at meeting points and then go together to the destination by public transport to reduce their global travel cost (e.g., energy, money, or greenhouse-gas emissions). This type of functionality holds the potential to bring significant benefits to society and the environment, such as reducing energy consumption and greenhouse-gas emissions, enabling smarter and greener transportation, and reducing traffic congestions. The CTP query is Max SNP-hard. To compute the query efficiently, we develop two algorithms, including an exact algorithm and an approximation algorithm. The exact algorithm is capable finding the optimal result for small values of k (e.g., k = 2) in interactive time, while the approximation algorithm, which has a 5-approximation ratio, is suitable for other situations. The performance of the CTP query is studied experimentally with real and synthetic spatial data.

  3. The United States Culture Collection Network (USCCN): Enhancing Microbial Genomics Research through Living Microbe Culture Collections

    Science.gov (United States)

    Boundy-Mills, Kyria; Hess, Matthias; Bennett, A. Rick; Ryan, Matthew; Kang, Seogchan; Nobles, David; Eisen, Jonathan A.; Inderbitzin, Patrik; Sitepu, Irnayuli R.; Torok, Tamas; Brown, Daniel R.; Cho, Juliana; Wertz, John E.; Mukherjee, Supratim; Cady, Sherry L.

    2015-01-01

    The mission of the United States Culture Collection Network (USCCN; http://usccn.org) is “to facilitate the safe and responsible utilization of microbial resources for research, education, industry, medicine, and agriculture for the betterment of human kind.” Microbial culture collections are a key component of life science research, biotechnology, and emerging global biobased economies. Representatives and users of several microbial culture collections from the United States and Europe gathered at the University of California, Davis, to discuss how collections of microorganisms can better serve users and stakeholders and to showcase existing resources available in public culture collections. PMID:26092453

  4. Collecting Social Network Data from Mobile Phone SIM Cards

    Science.gov (United States)

    Peseckas, Ryan

    2016-01-01

    I used a subscriber identity module card reader to copy the lists of saved contacts from 170 mobile phones in Fiji. This approach has both advantages and disadvantages compared to other techniques for collecting telephone network data. Copying phone contacts avoids recall biases associated with survey-based name generators. It also obviates the…

  5. Collective Study On Security Threats In VOIP Networks

    Directory of Open Access Journals (Sweden)

    Muhammad Zulkifl Hasan

    2017-01-01

    Full Text Available The Collective study will critically evaluate the voice over internet protocol VOIP Security threats issues amp challenges in the communication over the network the solution provided by different vendors. Authors will be discussing all security issues different protocols but main focus will be on SIP protocol its implementation and vendors VOIP security system.

  6. Droplet networks with incorporated protein diodes show collective properties

    Science.gov (United States)

    Maglia, Giovanni; Heron, Andrew J.; Hwang, William L.; Holden, Matthew A.; Mikhailova, Ellina; Li, Qiuhong; Cheley, Stephen; Bayley, Hagan

    2009-07-01

    Recently, we demonstrated that submicrolitre aqueous droplets submerged in an apolar liquid containing lipid can be tightly connected by means of lipid bilayers to form networks. Droplet interface bilayers have been used for rapid screening of membrane proteins and to form asymmetric bilayers with which to examine the fundamental properties of channels and pores. Networks, meanwhile, have been used to form microscale batteries and to detect light. Here, we develop an engineered protein pore with diode-like properties that can be incorporated into droplet interface bilayers in droplet networks to form devices with electrical properties including those of a current limiter, a half-wave rectifier and a full-wave rectifier. The droplet approach, which uses unsophisticated components (oil, lipid, salt water and a simple pore), can therefore be used to create multidroplet networks with collective properties that cannot be produced by droplet pairs.

  7. Collective Competence and Social Capital Analysis in Collaborative Networks

    Directory of Open Access Journals (Sweden)

    Janaina Macke

    2010-06-01

    Full Text Available The present paper addresses the issue of collective competence and social capital analysis for collaborative networks. The objective of the project is to understand how collaborative networks can be influenced considering the perspective of social capital and core competences. In this model we defend the emphasis on endogenous resources, once the technology is, in a general way, accessible to most of the companies and, therefore will not be a long term competitive advantage. The model shows that collaborative networks will be more competitive and successful if they invest in to core elements that are: organizational culture and people. Therefore, the model contributes for the researches in socio-organizational filed and provides a tool to evaluate collaborative networks.

  8. Wireless Power Transfer and Data Collection in Wireless Sensor Networks

    OpenAIRE

    Li, Kai; Ni, Wei; Duan, Lingjie; Abolhasan, Mehran; Niu, Jianwei

    2017-01-01

    In a rechargeable wireless sensor network, the data packets are generated by sensor nodes at a specific data rate, and transmitted to a base station. Moreover, the base station transfers power to the nodes by using Wireless Power Transfer (WPT) to extend their battery life. However, inadequately scheduling WPT and data collection causes some of the nodes to drain their battery and have their data buffer overflow, while the other nodes waste their harvested energy, which is more than they need...

  9. Networking Alone? Digital Communications and Collective Action in Vietnam

    Directory of Open Access Journals (Sweden)

    Sandra Kurfürst

    2015-01-01

    Full Text Available This article explores the potential for the formation of collective action in Vietnam. Referring to land and labour protests, bauxite mining, anti-China demonstrations, as well as the revision of the 1992 Constitution, the article examines the social movement repertoires diverse groups have adopted to reach their objectives. Drawing on social movement theory and communication power, this contribution shows that apart from access to the technology, citizens’ opportunities to participate in digital networks as well as access to the default communication network of the state are necessary prerequisites in order to attain public attention and possibly to achieve social change. Moreover, this article shows that existing power differentials in Vietnam are reproduced in digital space. It concludes that for different collective behaviours to result in a social movement, it is essential to “switch” and to connect the different networks. For the moment, the call to protect Vietnam’s sovereignty offers common ground for collective action.

  10. Household food waste collection: Building service networks through neighborhood expansion.

    Science.gov (United States)

    Armington, William R; Chen, Roger B

    2018-04-17

    In this paper we develop a residential food waste collection analysis and modeling framework that captures transportation costs faced by service providers in their initial stages of service provision. With this framework and model, we gain insights into network transportation costs and investigate possible service expansion scenarios faced by these organizations. We solve a vehicle routing problem (VRP) formulated for the residential neighborhood context using a heuristic approach developed. The scenarios considered follow a narrative where service providers start with an initial neighborhood or community and expands to incorporate other communities and their households. The results indicate that increasing household participation, decreases the travel time and cost per household, up to a critical threshold, beyond which we see marginal time and cost improvements. Additionally, the results indicate different outcomes in expansion scenarios depending on the household density of incorporated neighborhoods. As household participation and density increases, the travel time per household in the network decreases. However, at approximately 10-20 households per km 2 , the decrease in travel time per household is marginal, suggesting a lowerbound household density threshold. Finally, we show in food waste collection, networks share common scaling effects with respect to travel time and costs, regardless of the number of nodes and links. Copyright © 2018 Elsevier Ltd. All rights reserved.

  11. Uncovering collective listening habits and music genres in bipartite networks

    Science.gov (United States)

    Lambiotte, R.; Ausloos, M.

    2005-12-01

    In this paper, we analyze web-downloaded data on people sharing their music library, that we use as their individual musical signatures. The system is represented by a bipartite network, nodes being the music groups and the listeners. Music groups’ audience size behaves like a power law, but the individual music library size is an exponential with deviations at small values. In order to extract structures from the network, we focus on correlation matrices, that we filter by removing the least correlated links. This percolation idea-based method reveals the emergence of social communities and music genres, that are visualized by a branching representation. Evidence of collective listening habits that do not fit the neat usual genres defined by the music industry indicates an alternative way of classifying listeners and music groups. The structure of the network is also studied by a more refined method, based upon a random walk exploration of its properties. Finally, a personal identification-community imitation model for growing bipartite networks is outlined, following Potts ingredients. Simulation results do reproduce quite well the empirical data.

  12. Community, Collective or Movement? Evaluating Theoretical Perspectives on Network Building

    Science.gov (United States)

    Spitzer, W.

    2015-12-01

    Since 2007, the New England Aquarium has led a national effort to increase the capacity of informal science venues to effectively communicate about climate change. We are now leading the NSF-funded National Network for Ocean and Climate Change Interpretation (NNOCCI), partnering with the Association of Zoos and Aquariums, FrameWorks Institute, Woods Hole Oceanographic Institution, Monterey Bay Aquarium, and National Aquarium, with evaluation conducted by the New Knowledge Organization, Pennsylvania State University, and Ohio State University. NNOCCI enables teams of informal science interpreters across the country to serve as "communication strategists" - beyond merely conveying information they can influence public perceptions, given their high level of commitment, knowledge, public trust, social networks, and visitor contact. We provide in-depth training as well as an alumni network for ongoing learning, implementation support, leadership development, and coalition building. Our goals are to achieve a systemic national impact, embed our work within multiple ongoing regional and national climate change education networks, and leave an enduring legacy. What is the most useful theoretical model for conceptualizing the work of the NNOCCI community? This presentation will examine the pros and cons of three perspectives -- community of practice, collective impact, and social movements. The community of practice approach emphasizes use of common tools, support for practice, social learning, and organic development of leadership. A collective impact model focuses on defining common outcomes, aligning activities toward a common goal, structured collaboration. A social movement emphasizes building group identity and creating a sense of group efficacy. This presentation will address how these models compare in terms of their utility in program planning and evaluation, their fit with the unique characteristics of the NNOCCI community, and their relevance to our program goals.

  13. Indian Jute in Australian Collections: Forgetting and Recollecting Transnational Networks

    Directory of Open Access Journals (Sweden)

    Andrew Hassam

    2011-12-01

    Full Text Available Indian jute sacking played an essential role in Australian life for over 150 years, yet its contribution to Australian development and its Indian origins have been barely recognised in Australian public collections. What has Australian history gained by this erasing of jute from public memory? Wool, sugar and hop sacks are displayed in public collections as evidence of an Australian national story, but their national dimension depends on the cultural invisibility of jute and jute’s connections to the stories of other communities in other places. Developing an awareness of the contribution of Indian jute to the development of Australia requires an awareness not simply that jute comes from India but that the construction of national identity by collecting institutions relies on forgetting those transnational connections evident in their own collections. Where jute sacks have been preserved, it is because they are invested with memories of a collective way of life, yet in attempting to speak on behalf of the nation, the public museum denies more multidimensional models of cultural identity that are less linear and less place-based. If Indian jute is to be acknowledged as part of ‘the Australian story’, the concept of an Australian story must change and exhibitions need to explore, rather than ignore, transnational networks.

  14. Saving energy for the data collection point in WBAN network

    Science.gov (United States)

    Nguyen-Duc, Toan; Kamioka, Eiji

    2017-11-01

    Wireless sensor networking (WSN) has been rapidly developed and become essential in various domains including health care systems. Such systems use WSN to collect real-time medical sensed data, aiming at improving the patient safety. For instance, patients suffered from adverse events, i.e., cardiac or respiratory arrests, are monitored so as to prevent them from getting harm. Sensors are placed on, in or near the patients' body to continuously collect sensing data such as the electrocardiograms, blood oxygenation, breathing, and heart rate. In this case, the sensors form a subcategory of WSN called wireless body area network (WBAN). In WBAN, sensing data are sent to one or more data collection points called personal server (PS). The role of PS is important since it forwards sensed data, to a medical server via a Bluetooth/WLAN connection in real time to support storage of information and real-time diagnosis, the device can also issue a notification of an emergency status. Since PS is a battery-based device, when its battery is empty, it will disconnect the sensed medical data with the rest network. To best of our knowledge, very few studies that focus on saving energy for the PS. To this end, this work investigates the trade-off between energy consumption for wireless communication and the amount of sensing data. An energy consumption model for wireless communication has been proposed based on direct measurement using real testbed. According to our findings, it is possible to save energy for the PS by selecting suitable wireless technology to be used based on the amount of data to be transmitted.

  15. DC Collection Network Simulation for Offshore Wind Farms

    DEFF Research Database (Denmark)

    Vogel, Stephan; Rasmussen, Tonny Wederberg; El-Khatib, Walid Ziad

    2015-01-01

    The possibility to connect offshore wind turbines with a collection network based on Direct Current (DC), instead of Alternating Current (AC), gained attention in the scientific and industrial environment. There are many promising properties of DC components that could be beneficial such as......: smaller dimensions, less weight, fewer conductors, no reactive power considerations, and less overall losses due to the absence of proximity and skin effects. This work describes a study about the simulation of a Medium Voltage DC (MVDC) grid in an offshore wind farm. Suitable converter concepts...

  16. Cacades: A reliable dissemination protocol for data collection sensor network

    Science.gov (United States)

    Peng, Y.; Song, W.; Huang, R.; Xu, M.; Shirazi, B.; LaHusen, R.; Pei, G.

    2009-01-01

    In this paper, we propose a fast and reliable data dissemination protocol Cascades to disseminate data from the sink(base station) to all or a subset of nodes in a data collection sensor network. Cascades makes use of the parentmonitor-children analogy to ensure reliable dissemination. Each node monitors whether or not its children have received the broadcast messages through snooping children's rebroadcasts or waiting for explicit ACKs. If a node detects a gap in its message sequences, it can fetch the missing messages from its neighbours reactively. Cascades also considers many practical issues for field deployment, such as dynamic topology, link/node failure, etc.. It therefore guarantees that a disseminated message from the sink will reach all intended receivers and the dissemination is terminated in a short time period. Notice that, all existing dissemination protocols either do not guarantee reliability or do not terminate [1, 2], which does not meet the requirement of real-time command control. We conducted experiment evaluations in both TOSSIM simulator and a sensor network testbed to compare Cascades with those existing dissemination protocols in TinyOS sensor networks, which show that Cascades achieves a higher degree of reliability, lower communication cost, and less delivery delay. ??2009 IEEE.

  17. On effective temperature in network models of collective behavior

    International Nuclear Information System (INIS)

    Porfiri, Maurizio; Ariel, Gil

    2016-01-01

    Collective behavior of self-propelled units is studied analytically within the Vectorial Network Model (VNM), a mean-field approximation of the well-known Vicsek model. We propose a dynamical systems framework to study the stochastic dynamics of the VNM in the presence of general additive noise. We establish that a single parameter, which is a linear function of the circular mean of the noise, controls the macroscopic phase of the system—ordered or disordered. By establishing a fluctuation–dissipation relation, we posit that this parameter can be regarded as an effective temperature of collective behavior. The exact critical temperature is obtained analytically for systems with small connectivity, equivalent to low-density ensembles of self-propelled units. Numerical simulations are conducted to demonstrate the applicability of this new notion of effective temperature to the Vicsek model. The identification of an effective temperature of collective behavior is an important step toward understanding order–disorder phase transitions, informing consistent coarse-graining techniques and explaining the physics underlying the emergence of collective phenomena.

  18. Prioritized Degree Distribution in Wireless Sensor Networks with a Network Coded Data Collection Method

    Science.gov (United States)

    Wan, Jan; Xiong, Naixue; Zhang, Wei; Zhang, Qinchao; Wan, Zheng

    2012-01-01

    The reliability of wireless sensor networks (WSNs) can be greatly affected by failures of sensor nodes due to energy exhaustion or the influence of brutal external environment conditions. Such failures seriously affect the data persistence and collection efficiency. Strategies based on network coding technology for WSNs such as LTCDS can improve the data persistence without mass redundancy. However, due to the bad intermediate performance of LTCDS, a serious ‘cliff effect’ may appear during the decoding period, and source data are hard to recover from sink nodes before sufficient encoded packets are collected. In this paper, the influence of coding degree distribution strategy on the ‘cliff effect’ is observed and the prioritized data storage and dissemination algorithm PLTD-ALPHA is presented to achieve better data persistence and recovering performance. With PLTD-ALPHA, the data in sensor network nodes present a trend that their degree distribution increases along with the degree level predefined, and the persistent data packets can be submitted to the sink node according to its degree in order. Finally, the performance of PLTD-ALPHA is evaluated and experiment results show that PLTD-ALPHA can greatly improve the data collection performance and decoding efficiency, while data persistence is not notably affected. PMID:23235451

  19. Prioritized degree distribution in wireless sensor networks with a network coded data collection method.

    Science.gov (United States)

    Wan, Jan; Xiong, Naixue; Zhang, Wei; Zhang, Qinchao; Wan, Zheng

    2012-12-12

    The reliability of wireless sensor networks (WSNs) can be greatly affected by failures of sensor nodes due to energy exhaustion or the influence of brutal external environment conditions. Such failures seriously affect the data persistence and collection efficiency. Strategies based on network coding technology for WSNs such as LTCDS can improve the data persistence without mass redundancy. However, due to the bad intermediate performance of LTCDS, a serious 'cliff effect' may appear during the decoding period, and source data are hard to recover from sink nodes before sufficient encoded packets are collected. In this paper, the influence of coding degree distribution strategy on the 'cliff effect' is observed and the prioritized data storage and dissemination algorithm PLTD-ALPHA is presented to achieve better data persistence and recovering performance. With PLTD-ALPHA, the data in sensor network nodes present a trend that their degree distribution increases along with the degree level predefined, and the persistent data packets can be submitted to the sink node according to its degree in order. Finally, the performance of PLTD-ALPHA is evaluated and experiment results show that PLTD-ALPHA can greatly improve the data collection performance and decoding efficiency, while data persistence is not notably affected.

  20. Collective signaling behavior in a networked-oscillator model

    Science.gov (United States)

    Liu, Z.-H.; Hui, P. M.

    2007-09-01

    We propose and study the collective behavior of a model of networked signaling objects that incorporates several ingredients of real-life systems. These ingredients include spatial inhomogeneity with grouping of signaling objects, signal attenuation with distance, and delayed and impulsive coupling between non-identical signaling objects. Depending on the coupling strength and/or time-delay effect, the model exhibits completely, partially, and locally collective signaling behavior. In particular, a correlated signaling (CS) behavior is observed in which there exist time durations when nearly a constant fraction of oscillators in the system are in the signaling state. These time durations are much longer than the duration of a spike when a single oscillator signals, and they are separated by regular intervals in which nearly all oscillators are silent. Such CS behavior is similar to that observed in biological systems such as fireflies, cicadas, crickets, and frogs. The robustness of the CS behavior against noise is also studied. It is found that properly adjusting the coupling strength and noise level could enhance the correlated behavior.

  1. OzFlux data: network integration from collection to curation

    Directory of Open Access Journals (Sweden)

    P. Isaac

    2017-06-01

    Full Text Available Measurement of the exchange of energy and mass between the surface and the atmospheric boundary-layer by the eddy covariance technique has undergone great change in the last 2 decades. Early studies of these exchanges were confined to brief field campaigns in carefully controlled conditions followed by months of data analysis. Current practice is to run tower-based eddy covariance systems continuously over several years due to the need for continuous monitoring as part of a global effort to develop local-, regional-, continental- and global-scale budgets of carbon, water and energy. Efficient methods of processing the increased quantities of data are needed to maximise the time available for analysis and interpretation. Standardised methods are needed to remove differences in data processing as possible contributors to observed spatial variability. Furthermore, public availability of these data sets assists with undertaking global research efforts. The OzFlux data path has been developed (i to provide a standard set of quality control and post-processing tools across the network, thereby facilitating inter-site integration and spatial comparisons; (ii to increase the time available to researchers for analysis and interpretation by reducing the time spent collecting and processing data; (iii to propagate both data and metadata to the final product; and (iv to facilitate the use of the OzFlux data by adopting a standard file format and making the data available from web-based portals. Discovery of the OzFlux data set is facilitated through incorporation in FLUXNET data syntheses and the publication of collection metadata via the RIF-CS format. This paper serves two purposes. The first is to describe the data sets, along with their quality control and post-processing, for the other papers of this Special Issue. The second is to provide an example of one solution to the data collection and curation challenges that are encountered by similar flux

  2. High-speed and high-fidelity system and method for collecting network traffic

    Science.gov (United States)

    Weigle, Eric H [Los Alamos, NM

    2010-08-24

    A system is provided for the high-speed and high-fidelity collection of network traffic. The system can collect traffic at gigabit-per-second (Gbps) speeds, scale to terabit-per-second (Tbps) speeds, and support additional functions such as real-time network intrusion detection. The present system uses a dedicated operating system for traffic collection to maximize efficiency, scalability, and performance. A scalable infrastructure and apparatus for the present system is provided by splitting the work performed on one host onto multiple hosts. The present system simultaneously addresses the issues of scalability, performance, cost, and adaptability with respect to network monitoring, collection, and other network tasks. In addition to high-speed and high-fidelity network collection, the present system provides a flexible infrastructure to perform virtually any function at high speeds such as real-time network intrusion detection and wide-area network emulation for research purposes.

  3. Optimal UAS Assignments and Trajectories for Persistent Surveillance and Data Collection from a Wireless Sensor Network

    Science.gov (United States)

    2015-12-24

    Optimal UAS Assignments and Trajectories for Persistent Surveillance and Data Collection from a Wireless Sensor Network DISSERTATION Nidal M. Jodeh...ASSIGNMENTS AND TRAJECTORIES FOR PERSISTENT SURVEILLANCE AND DATA COLLECTION FROM A WIRELESS SENSOR NETWORK DISSERTATION Presented to the Faculty...COLLECTION FROM A WIRELESS SENSOR NETWORK Nidal M. Jodeh, B.S., M.A.S., M.S. Lieutenant Colonel, USAF Committee Membership: Richard G. Cobb, PhD Chairman

  4. Phase reduction and synchronization of a network of coupled dynamical elements exhibiting collective oscillations

    Science.gov (United States)

    Nakao, Hiroya; Yasui, Sho; Ota, Masashi; Arai, Kensuke; Kawamura, Yoji

    2018-04-01

    A general phase reduction method for a network of coupled dynamical elements exhibiting collective oscillations, which is applicable to arbitrary networks of heterogeneous dynamical elements, is developed. A set of coupled adjoint equations for phase sensitivity functions, which characterize the phase response of the collective oscillation to small perturbations applied to individual elements, is derived. Using the phase sensitivity functions, collective oscillation of the network under weak perturbation can be described approximately by a one-dimensional phase equation. As an example, mutual synchronization between a pair of collectively oscillating networks of excitable and oscillatory FitzHugh-Nagumo elements with random coupling is studied.

  5. Physical parameters collection based on wireless senor network

    Science.gov (United States)

    Chen, Xin; Wu, Hong; Ji, Lei

    2013-12-01

    With the development of sensor technology, wireless senor network has been applied in the medical, military, entertainment field and our daily life. But the existing available wireless senor networks applied in human monitoring system still have some problems, such as big power consumption, low security and so on. To improve senor network applied in health monitoring system, the paper introduces a star wireless senor networks based on msp430 and DSP. We design a low-cost heart-rate monitor senor node. The communication between senor node and sink node is realized according to the newest protocol proposed by the IEEE 802.15.6 Task Group. This wireless senor network will be more energy-efficient and faster compared to traditional senor networks.

  6. Social Networks and Collective Intelligence: A Return to the Agora

    DEFF Research Database (Denmark)

    Mazzara, Manuel; Biselli, Luca; Greco, Pier Paolo

    2013-01-01

    backgrounds and institutes with significantly different agendas. Polidoxa aims at offering: 1) a trust-based search engine algorithm, which exploits stigmergic behaviours of users? network, 2) a trust-based social network, where the notion of trust derives from network activity and 3) a holonic system...... for bottom-up self-protection and social privacy. By presenting the Polidoxa solution, this work also describes the current state of traditional media as well as newer ones, providing an accurate analysis of major search engines such as Google and social network (e.g., Facebook). The advantages that Polidoxa...

  7. 78 FR 3447 - Information Collection: Southern Alaska Sharing Network and Subsistence Study; Submitted for OMB...

    Science.gov (United States)

    2013-01-16

    ... local sharing networks that structure contemporary subsistence-cash economies using research methods... Collection: Southern Alaska Sharing Network and Subsistence Study; Submitted for OMB Review; Comment Request... conducting a survey on subsistence and sharing networks in coastal Alaska. This notice provides the public a...

  8. Fragmenting networks by targeting collective influencers at a mesoscopic level

    Science.gov (United States)

    Kobayashi, Teruyoshi; Masuda, Naoki

    2016-11-01

    A practical approach to protecting networks against epidemic processes such as spreading of infectious diseases, malware, and harmful viral information is to remove some influential nodes beforehand to fragment the network into small components. Because determining the optimal order to remove nodes is a computationally hard problem, various approximate algorithms have been proposed to efficiently fragment networks by sequential node removal. Morone and Makse proposed an algorithm employing the non-backtracking matrix of given networks, which outperforms various existing algorithms. In fact, many empirical networks have community structure, compromising the assumption of local tree-like structure on which the original algorithm is based. We develop an immunization algorithm by synergistically combining the Morone-Makse algorithm and coarse graining of the network in which we regard a community as a supernode. In this way, we aim to identify nodes that connect different communities at a reasonable computational cost. The proposed algorithm works more efficiently than the Morone-Makse and other algorithms on networks with community structure.

  9. Applied network security monitoring collection, detection, and analysis

    CERN Document Server

    Sanders, Chris

    2013-01-01

    Applied Network Security Monitoring is the essential guide to becoming an NSM analyst from the ground up. This book takes a fundamental approach to NSM, complete with dozens of real-world examples that teach you the key concepts of NSM. Network security monitoring is based on the principle that prevention eventually fails. In the current threat landscape, no matter how much you try, motivated attackers will eventually find their way into your network. At that point, it is your ability to detect and respond to that intrusion that can be the difference between a small incident and a major di

  10. automatic data collection design for neural networks detection

    African Journals Online (AJOL)

    Dr Obe

    Automated data collection is necessary to alleviate problems inherent in data collection for investigation ... (iv) Costs the employing organisation assets, ..... velocity (rate of cash flow over a period of time). ... Mining and Knowledge Discovery,.

  11. Automatic Data Collection Design for Neural Networks Detection of ...

    African Journals Online (AJOL)

    Automated data collection is necessary to alleviate problems inherent in data collection for investigation of management frauds. Once we have gathered a realistic data, several methods then exist for proper analysis and detection of anomalous transactions. However, in Nigeria, collecting fraudulent data is relatively difficult ...

  12. Data Collection Method for Mobile Control Sink Node in Wireless Sensor Network Based on Compressive Sensing

    Directory of Open Access Journals (Sweden)

    Ling Yongfa

    2016-01-01

    Full Text Available The paper proposes a mobile control sink node data collection method in the wireless sensor network based on compressive sensing. This method, with regular track, selects the optimal data collection points in the monitoring area via the disc method, calcu-lates the shortest path by using the quantum genetic algorithm, and hence determines the data collection route. Simulation results show that this method has higher network throughput and better energy efficiency, capable of collecting a huge amount of data with balanced energy consumption in the network.

  13. Government information collections in the networked environment new issues and models

    CERN Document Server

    Cheverie, Joan F

    2013-01-01

    This insightful book explores the challenging issues related to effective access to government information.Amidst all the chaos of today's dynamic information transition period, the only constants related to government information are change and inconsistency, yet with Government Information Collections in the Networked Environment: New Issues and Models, you will defeat the challenging issues and take advantage of the opportunities that networked government information collections have to offer. This valuable book gives you a fresh opportunity to rethink collecting activities and to

  14. Road networks as collections of minimum cost paths

    Science.gov (United States)

    Wegner, Jan Dirk; Montoya-Zegarra, Javier Alexander; Schindler, Konrad

    2015-10-01

    We present a probabilistic representation of network structures in images. Our target application is the extraction of urban roads from aerial images. Roads appear as thin, elongated, partially curved structures forming a loopy graph, and this complex layout requires a prior that goes beyond standard smoothness and co-occurrence assumptions. In the proposed model the network is represented as a union of 1D paths connecting distant (super-)pixels. A large set of putative candidate paths is constructed in such a way that they include the true network as much as possible, by searching for minimum cost paths in the foreground (road) likelihood. Selecting the optimal subset of candidate paths is posed as MAP inference in a higher-order conditional random field. Each path forms a higher-order clique with a type of clique potential, which attracts the member nodes of cliques with high cumulative road evidence to the foreground label. That formulation induces a robust PN -Potts model, for which a global MAP solution can be found efficiently with graph cuts. Experiments with two road data sets show that the proposed model significantly improves per-pixel accuracies as well as the overall topological network quality with respect to several baselines.

  15. Collective frequency variation in network synchronization and reverse PageRank.

    Science.gov (United States)

    Skardal, Per Sebastian; Taylor, Dane; Sun, Jie; Arenas, Alex

    2016-04-01

    A wide range of natural and engineered phenomena rely on large networks of interacting units to reach a dynamical consensus state where the system collectively operates. Here we study the dynamics of self-organizing systems and show that for generic directed networks the collective frequency of the ensemble is not the same as the mean of the individuals' natural frequencies. Specifically, we show that the collective frequency equals a weighted average of the natural frequencies, where the weights are given by an outflow centrality measure that is equivalent to a reverse PageRank centrality. Our findings uncover an intricate dependence of the collective frequency on both the structural directedness and dynamical heterogeneity of the network, and also reveal an unexplored connection between synchronization and PageRank, which opens the possibility of applying PageRank optimization to synchronization. Finally, we demonstrate the presence of collective frequency variation in real-world networks by considering the UK and Scandinavian power grids.

  16. Collective frequency variation in network synchronization and reverse PageRank

    Science.gov (United States)

    Skardal, Per Sebastian; Taylor, Dane; Sun, Jie; Arenas, Alex

    2016-04-01

    A wide range of natural and engineered phenomena rely on large networks of interacting units to reach a dynamical consensus state where the system collectively operates. Here we study the dynamics of self-organizing systems and show that for generic directed networks the collective frequency of the ensemble is not the same as the mean of the individuals' natural frequencies. Specifically, we show that the collective frequency equals a weighted average of the natural frequencies, where the weights are given by an outflow centrality measure that is equivalent to a reverse PageRank centrality. Our findings uncover an intricate dependence of the collective frequency on both the structural directedness and dynamical heterogeneity of the network, and also reveal an unexplored connection between synchronization and PageRank, which opens the possibility of applying PageRank optimization to synchronization. Finally, we demonstrate the presence of collective frequency variation in real-world networks by considering the UK and Scandinavian power grids.

  17. Phytoplankton Monitoring Network - Phytoplankton Analysis with Associated Collection Information

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A qualitative collection of data that includes salinity, temperature, phytoplankton counts and abundance ratios obtained from surface tows in the estuarine and...

  18. Opportunistic Data Collection in Sparse Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Franceschinis Mirko

    2011-01-01

    Full Text Available Opportunistic wireless sensor networks (WSNs have recently been proposed as solutions for many remote monitoring problems. Many such problems, including environmental monitoring, involve large deployment scenarios with lower-than-average node density, as well as a long time scale and limited budgets. Traditional approaches designed for conventional situations, and thus not optimized for these scenarios, entail unnecessary complexity and larger costs. This paper discusses the issues related with the design and test of opportunistic architectures, and presents one possible solution—CHARON (Convergent Hybrid-replication Approach to Routing in Opportunistic Networks. Both algorithm-specific and comparative simulation results are presented, as well as real-world tests using a reference implementation. A comprehensive experimental setup was also used to seek a full characterization of the devised opportunistic approach including the derivation of a simple analytical model that is able to accurately predict the opportunistic message delivery performance in the used test bed.

  19. Information Collection using Handheld Devices in Unreliable Networking Environments

    Science.gov (United States)

    2014-06-01

    joint logistics operations center JMS Java Message System JUNG Java Universal Network/Graph Framework KTG Kestral Technology Group MILOB... Java Message System, a Publisher/Subscriber system that is explained in greater detail at either Oracle’s JMS site (Oracle 2014) or the JMS Wikipedia...Google’s infrastructure and local servers with MySQL and PostgreSQL on the backend (ODK 2014b). (2) Google Fusion Tables are used to do basic link

  20. Collective navigation of complex networks: Participatory greedy routing.

    Science.gov (United States)

    Kleineberg, Kaj-Kolja; Helbing, Dirk

    2017-06-06

    Many networks are used to transfer information or goods, in other words, they are navigated. The larger the network, the more difficult it is to navigate efficiently. Indeed, information routing in the Internet faces serious scalability problems due to its rapid growth, recently accelerated by the rise of the Internet of Things. Large networks like the Internet can be navigated efficiently if nodes, or agents, actively forward information based on hidden maps underlying these systems. However, in reality most agents will deny to forward messages, which has a cost, and navigation is impossible. Can we design appropriate incentives that lead to participation and global navigability? Here, we present an evolutionary game where agents share the value generated by successful delivery of information or goods. We show that global navigability can emerge, but its complete breakdown is possible as well. Furthermore, we show that the system tends to self-organize into local clusters of agents who participate in the navigation. This organizational principle can be exploited to favor the emergence of global navigability in the system.

  1. Novel Framework for Data Collection in Wireless Sensor Networks Using Flying Sensors

    DEFF Research Database (Denmark)

    Mathur, Prateek; Nielsen, Rasmus Hjorth; Prasad, Neeli R.

    2014-01-01

    This paper proposes a novel framework for data collection from a sensor network using flying sensor nodes. Efficient data communication within the network is a necessity as sensor nodes are usually energy constrained. The proposed framework utilizes the various entities forming the network...... for a different utility compared to their usual role in sensor networks. Use of flying sensor nodes is usually considered for conventional purpose of sensing and monitoring. Flying sensing nodes are usually utilized collectively in the form of an aerial sensor network, they are not expected to function as a data...... collection entity, as proposed in this framework. Similarly, cluster heads (CHs) are usually expected to transfer the aggregated data to an adjoining CH or to the base station (BS) directly. In the proposed framework the CH transfers data directly to the flying sensor node, averting the need for energy...

  2. Smart Collection and Storage Method for Network Traffic Data

    Science.gov (United States)

    2014-09-01

    to the root of an incident or under- stand what goes on in a network may mean looking at data from weeks, months, or even years ago, as has been the...KB 1.01% 69.42 TB 694.20 TB 6,941.99 TB SuSE 6.3 .pcap 51,706 KB 1.01% 104.03 TB 1,040.27 TB 10,402.68 TB HP-UX nettl .trc0 53,391 KB 1.04% 451.13

  3. Intelligence Collection Targeting and Interdiction of Dark Networks

    Science.gov (United States)

    2014-06-01

    examples of terrorist technological communications countered by a baseline of NTM collection with OSINT and HUMINT only serving as enablers or...he visits while traveling as an ostensible tourist ( OSINT ) would be useful.54 In summary, Sims’s observation not only enforce the strategic

  4. Analysis Of Data Collected By Epidemio-Surveillance Network For ...

    African Journals Online (AJOL)

    Summary During the period 1996 - 2002, 82 suspected cases of pasteurellosis were recorded and 88 samples taken from suspected animals were collected and analysed by the national laboratory Laboratoire de Recherches Vétérinaires et Zootechniques de Farcha. Out of 82 suspected cases, only 7 % were confirmed by ...

  5. A radio network collects the data sent by the sensors

    International Nuclear Information System (INIS)

    Zani-Demange, M.L.

    2008-01-01

    The Malvesi site in southern France is the most important uranium conversion plant in the world. It belongs to Comurhex and its purpose is to turn uranium ore into uranium tetrafluoride (UF 4 ). This transformation requires successive purification stages for the ore. This purification process generates large amount of liquid effluents containing nitrates. Large reservoirs in open air covering an area of about 80 hectares are used to evaporate water and concentrate the effluents. A new system based on a network of ultrasound level sensors that send information to the control room through radio waves, is operating to control the levels of the reservoirs. For some reservoirs solar panels supply energy for the sensors and the radio modem. The main assets of this wireless installation is its reduced cost compared to the cost of setting a cable network and its flexibility when an ancient reservoir is put aside or when a new one is added, the installation can be easily moved. (A.C.)

  6. A Feedback-Based Secure Path Approach for Wireless Sensor Network Data Collection

    Science.gov (United States)

    Mao, Yuxin; Wei, Guiyi

    2010-01-01

    The unattended nature of wireless sensor networks makes them very vulnerable to malicious attacks. Therefore, how to preserve secure data collection is an important issue to wireless sensor networks. In this paper, we propose a novel approach of secure data collection for wireless sensor networks. We explore secret sharing and multipath routing to achieve secure data collection in wireless sensor network with compromised nodes. We present a novel tracing-feedback mechanism, which makes full use of the routing functionality of wireless sensor networks, to improve the quality of data collection. The major advantage of the approach is that the secure paths are constructed as a by-product of data collection. The process of secure routing causes little overhead to the sensor nodes in the network. Compared with existing works, the algorithms of the proposed approach are easy to implement and execute in resource-constrained wireless sensor networks. According to the result of a simulation experiment, the performance of the approach is better than the recent approaches with a similar purpose. PMID:22163424

  7. A Feedback-Based Secure Path Approach for Wireless Sensor Network Data Collection

    Directory of Open Access Journals (Sweden)

    Guiyi Wei

    2010-10-01

    Full Text Available The unattended nature of wireless sensor networks makes them very vulnerable to malicious attacks. Therefore, how to preserve secure data collection is an important issue to wireless sensor networks. In this paper, we propose a novel approach of secure data collection for wireless sensor networks. We explore secret sharing and multipath routing to achieve secure data collection in wireless sensor network with compromised nodes. We present a novel tracing-feedback mechanism, which makes full use of the routing functionality of wireless sensor networks, to improve the quality of data collection. The major advantage of the approach is that the secure paths are constructed as a by-product of data collection. The process of secure routing causes little overhead to the sensor nodes in the network. Compared with existing works, the algorithms of the proposed approach are easy to implement and execute in resource-constrained wireless sensor networks. According to the result of a simulation experiment, the performance of the approach is better than the recent approaches with a similar purpose.

  8. A feedback-based secure path approach for wireless sensor network data collection.

    Science.gov (United States)

    Mao, Yuxin; Wei, Guiyi

    2010-01-01

    The unattended nature of wireless sensor networks makes them very vulnerable to malicious attacks. Therefore, how to preserve secure data collection is an important issue to wireless sensor networks. In this paper, we propose a novel approach of secure data collection for wireless sensor networks. We explore secret sharing and multipath routing to achieve secure data collection in wireless sensor network with compromised nodes. We present a novel tracing-feedback mechanism, which makes full use of the routing functionality of wireless sensor networks, to improve the quality of data collection. The major advantage of the approach is that the secure paths are constructed as a by-product of data collection. The process of secure routing causes little overhead to the sensor nodes in the network. Compared with existing works, the algorithms of the proposed approach are easy to implement and execute in resource-constrained wireless sensor networks. According to the result of a simulation experiment, the performance of the approach is better than the recent approaches with a similar purpose.

  9. From social network (centralized vs. decentralized to collective decision-making (unshared vs. shared consensus.

    Directory of Open Access Journals (Sweden)

    Cédric Sueur

    Full Text Available Relationships we have with our friends, family, or colleagues influence our personal decisions, as well as decisions we make together with others. As in human beings, despotism and egalitarian societies seem to also exist in animals. While studies have shown that social networks constrain many phenomena from amoebae to primates, we still do not know how consensus emerges from the properties of social networks in many biological systems. We created artificial social networks that represent the continuum from centralized to decentralized organization and used an agent-based model to make predictions about the patterns of consensus and collective movements we observed according to the social network. These theoretical results showed that different social networks and especially contrasted ones--star network vs. equal network--led to totally different patterns. Our model showed that, by moving from a centralized network to a decentralized one, the central individual seemed to lose its leadership in the collective movement's decisions. We, therefore, showed a link between the type of social network and the resulting consensus. By comparing our theoretical data with data on five groups of primates, we confirmed that this relationship between social network and consensus also appears to exist in animal societies.

  10. From social network (centralized vs. decentralized) to collective decision-making (unshared vs. shared consensus).

    Science.gov (United States)

    Sueur, Cédric; Deneubourg, Jean-Louis; Petit, Odile

    2012-01-01

    Relationships we have with our friends, family, or colleagues influence our personal decisions, as well as decisions we make together with others. As in human beings, despotism and egalitarian societies seem to also exist in animals. While studies have shown that social networks constrain many phenomena from amoebae to primates, we still do not know how consensus emerges from the properties of social networks in many biological systems. We created artificial social networks that represent the continuum from centralized to decentralized organization and used an agent-based model to make predictions about the patterns of consensus and collective movements we observed according to the social network. These theoretical results showed that different social networks and especially contrasted ones--star network vs. equal network--led to totally different patterns. Our model showed that, by moving from a centralized network to a decentralized one, the central individual seemed to lose its leadership in the collective movement's decisions. We, therefore, showed a link between the type of social network and the resulting consensus. By comparing our theoretical data with data on five groups of primates, we confirmed that this relationship between social network and consensus also appears to exist in animal societies.

  11. Google Correlations: New approaches to collecting data for statistical network analysis

    Science.gov (United States)

    Mahdavi, Paasha

    This thesis introduces a new method for data collection on political elite networks using non-obtrusive web-based techniques. One possible indicator of elite connectivity is the frequency with which individuals appear at the same political events. Using a Google search scraping algorithm (Lee 2010) to capture how often pairs of individuals appear in the same news articles reporting on these events, I construct network matrices for a given list of individuals that I identify as elites using a variety of criteria. To assess cross-validity and conceptual accuracy, I compare data from this method to previously collected data on the network connectedness of three separate populations. I then supply an application of the Google method to collect network data on the Nigerian oil elite in 2012. Conducting a network analysis, I show that appointments to the Nigerian National Petroleum Corporation board of directors are made on the basis of political connectivity and not necessarily on technical experience or merit. These findings lend support to hypotheses that leaders use patronage appointments to lucrative bureaucratic positions in order to satisfy political elites. Given that many political theories on elite behavior aim to understand individual- and group-level interactions, the potential applicability of network data using the proposed technique is very large, especially in situations where collecting network data intrusively is costly or prohibitive.

  12. Branch-Based Centralized Data Collection for Smart Grids Using Wireless Sensor Networks

    OpenAIRE

    Kwangsoo Kim; Seong-il Jin

    2015-01-01

    A smart grid is one of the most important applications in smart cities. In a smart grid, a smart meter acts as a sensor node in a sensor network, and a central device collects power usage from every smart meter. This paper focuses on a centralized data collection problem of how to collect every power usage from every meter without collisions in an environment in which the time synchronization among smart meters is not guaranteed. To solve the problem, we divide a tree that a sensor network co...

  13. Collective Efficacy of a Regional Network: Extending the Social Embeddedness Perspective of Entrepreneurship

    OpenAIRE

    Muhammad, Nabeel; Léo-Paul, Dana

    2015-01-01

    Through participatory observation and in-depth interviews with members of the Memon community, in Pakistan, this paper probes into how the collective efforts of a regional network can facilitate entrepreneurship, social enterprises and regional development. The setting is a developing country that is lacking a large-scale entrepreneurial culture. Despite caste differences, Memons throughout the Karachi region meet and share experiences with other Memon members of their network – including Mem...

  14. Applications of deep convolutional neural networks to digitized natural history collections

    Directory of Open Access Journals (Sweden)

    Eric Schuettpelz

    2017-11-01

    Full Text Available Natural history collections contain data that are critical for many scientific endeavors. Recent efforts in mass digitization are generating large datasets from these collections that can provide unprecedented insight. Here, we present examples of how deep convolutional neural networks can be applied in analyses of imaged herbarium specimens. We first demonstrate that a convolutional neural network can detect mercury-stained specimens across a collection with 90% accuracy. We then show that such a network can correctly distinguish two morphologically similar plant families 96% of the time. Discarding the most challenging specimen images increases accuracy to 94% and 99%, respectively. These results highlight the importance of mass digitization and deep learning approaches and reveal how they can together deliver powerful new investigative tools.

  15. Applications of deep convolutional neural networks to digitized natural history collections.

    Science.gov (United States)

    Schuettpelz, Eric; Frandsen, Paul B; Dikow, Rebecca B; Brown, Abel; Orli, Sylvia; Peters, Melinda; Metallo, Adam; Funk, Vicki A; Dorr, Laurence J

    2017-01-01

    Natural history collections contain data that are critical for many scientific endeavors. Recent efforts in mass digitization are generating large datasets from these collections that can provide unprecedented insight. Here, we present examples of how deep convolutional neural networks can be applied in analyses of imaged herbarium specimens. We first demonstrate that a convolutional neural network can detect mercury-stained specimens across a collection with 90% accuracy. We then show that such a network can correctly distinguish two morphologically similar plant families 96% of the time. Discarding the most challenging specimen images increases accuracy to 94% and 99%, respectively. These results highlight the importance of mass digitization and deep learning approaches and reveal how they can together deliver powerful new investigative tools.

  16. The simplest maximum entropy model for collective behavior in a neural network

    International Nuclear Information System (INIS)

    Tkačik, Gašper; Marre, Olivier; Mora, Thierry; Amodei, Dario; Bialek, William; Berry II, Michael J

    2013-01-01

    Recent work emphasizes that the maximum entropy principle provides a bridge between statistical mechanics models for collective behavior in neural networks and experiments on networks of real neurons. Most of this work has focused on capturing the measured correlations among pairs of neurons. Here we suggest an alternative, constructing models that are consistent with the distribution of global network activity, i.e. the probability that K out of N cells in the network generate action potentials in the same small time bin. The inverse problem that we need to solve in constructing the model is analytically tractable, and provides a natural ‘thermodynamics’ for the network in the limit of large N. We analyze the responses of neurons in a small patch of the retina to naturalistic stimuli, and find that the implied thermodynamics is very close to an unusual critical point, in which the entropy (in proper units) is exactly equal to the energy. (paper)

  17. Collective multipartite Einstein-Podolsky-Rosen steering: more secure optical networks.

    Science.gov (United States)

    Wang, Meng; Gong, Qihuang; He, Qiongyi

    2014-12-01

    Collective multipartite Einstein-Podolsky-Rosen (EPR) steering is a type of quantum correlation shared among N parties, where the EPR paradox of one party can only be realized by performing local measurements on all the remaining N-1 parties. We formalize the collective tripartite steering in terms of local hidden state model and give the steering inequalities that act as signatures and suggest how to optimize collective tripartite steering in specific optical schemes. The special entangled states with property of collective multipartite steering may have potential applications in ultra-secure multiuser communication networks where the issue of trust is critical.

  18. The simplest problem in the collective dynamics of neural networks: is synchrony stable?

    International Nuclear Information System (INIS)

    Timme, Marc; Wolf, Fred

    2008-01-01

    For spiking neural networks we consider the stability problem of global synchrony, arguably the simplest non-trivial collective dynamics in such networks. We find that even this simplest dynamical problem—local stability of synchrony—is non-trivial to solve and requires novel methods for its solution. In particular, the discrete mode of pulsed communication together with the complicated connectivity of neural interaction networks requires a non-standard approach. The dynamics in the vicinity of the synchronous state is determined by a multitude of linear operators, in contrast to a single stability matrix in conventional linear stability theory. This unusual property qualitatively depends on network topology and may be neglected for globally coupled homogeneous networks. For generic networks, however, the number of operators increases exponentially with the size of the network. We present methods to treat this multi-operator problem exactly. First, based on the Gershgorin and Perron–Frobenius theorems, we derive bounds on the eigenvalues that provide important information about the synchronization process but are not sufficient to establish the asymptotic stability or instability of the synchronous state. We then present a complete analysis of asymptotic stability for topologically strongly connected networks using simple graph-theoretical considerations. For inhibitory interactions between dissipative (leaky) oscillatory neurons the synchronous state is stable, independent of the parameters and the network connectivity. These results indicate that pulse-like interactions play a profound role in network dynamical systems, and in particular in the dynamics of biological synchronization, unless the coupling is homogeneous and all-to-all. The concepts introduced here are expected to also facilitate the exact analysis of more complicated dynamical network states, for instance the irregular balanced activity in cortical neural networks

  19. CPAC: Energy-Efficient Data Collection through Adaptive Selection of Compression Algorithms for Sensor Networks

    Science.gov (United States)

    Lee, HyungJune; Kim, HyunSeok; Chang, Ik Joon

    2014-01-01

    We propose a technique to optimize the energy efficiency of data collection in sensor networks by exploiting a selective data compression. To achieve such an aim, we need to make optimal decisions regarding two aspects: (1) which sensor nodes should execute compression; and (2) which compression algorithm should be used by the selected sensor nodes. We formulate this problem into binary integer programs, which provide an energy-optimal solution under the given latency constraint. Our simulation results show that the optimization algorithm significantly reduces the overall network-wide energy consumption for data collection. In the environment having a stationary sink from stationary sensor nodes, the optimized data collection shows 47% energy savings compared to the state-of-the-art collection protocol (CTP). More importantly, we demonstrate that our optimized data collection provides the best performance in an intermittent network under high interference. In such networks, we found that the selective compression for frequent packet retransmissions saves up to 55% energy compared to the best known protocol. PMID:24721763

  20. Citizen science networks in natural history and the collective validation of biodiversity data.

    Science.gov (United States)

    Turnhout, Esther; Lawrence, Anna; Turnhout, Sander

    2016-06-01

    Biodiversity data are in increasing demand to inform policy and management. A substantial portion of these data is generated in citizen science networks. To ensure the quality of biodiversity data, standards and criteria for validation have been put in place. We used interviews and document analysis from the United Kingdom and The Netherlands to examine how data validation serves as a point of connection between the diverse people and practices in natural history citizen science networks. We found that rather than a unidirectional imposition of standards, validation was performed collectively. Specifically, it was enacted in ongoing circulations of biodiversity records between recorders and validators as they jointly negotiated the biodiversity that was observed and the validity of the records. These collective validation practices contributed to the citizen science character or natural history networks and tied these networks together. However, when biodiversity records were included in biodiversity-information initiatives on different policy levels and scales, the circulation of records diminished. These initiatives took on a more extractive mode of data use. Validation ceased to be collective with important consequences for the natural history networks involved and citizen science more generally. © 2016 The Authors. Conservation Biology published by Wiley Periodicals, Inc. on behalf of Society for Conservation Biology.

  1. Collecting sustainability data in different organisational settings of the European Farm Accountancy Data Network

    NARCIS (Netherlands)

    Vrolijk, H.C.J.; Poppe, K.J.; Keszthelyi, Szilard

    2016-01-01

    The European Farm Accountancy Data Network (FADN) collects detailed financial economic information on a sample of farms in Europe. These data are used intensively for the evaluation of the European Union’s Common Agricultural Policy. Owing to changes in policies, there is a need for a broader set of

  2. Design of artificial neural networks using a genetic algorithm to predict collection efficiency in venturi scrubbers.

    Science.gov (United States)

    Taheri, Mahboobeh; Mohebbi, Ali

    2008-08-30

    In this study, a new approach for the auto-design of neural networks, based on a genetic algorithm (GA), has been used to predict collection efficiency in venturi scrubbers. The experimental input data, including particle diameter, throat gas velocity, liquid to gas flow rate ratio, throat hydraulic diameter, pressure drop across the venturi scrubber and collection efficiency as an output, have been used to create a GA-artificial neural network (ANN) model. The testing results from the model are in good agreement with the experimental data. Comparison of the results of the GA optimized ANN model with the results from the trial-and-error calibrated ANN model indicates that the GA-ANN model is more efficient. Finally, the effects of operating parameters such as liquid to gas flow rate ratio, throat gas velocity, and particle diameter on collection efficiency were determined.

  3. Modelling energy production by small hydro power plants in collective irrigation networks of Calabria (Southern Italy)

    Science.gov (United States)

    Zema, Demetrio Antonio; Nicotra, Angelo; Tamburino, Vincenzo; Marcello Zimbone, Santo

    2017-04-01

    The availability of geodetic heads and considerable water flows in collective irrigation networks suggests the possibility of recovery potential energy using small hydro power plants (SHPP) at sustainable costs. This is the case of many Water Users Associations (WUA) in Calabria (Southern Italy), where it could theoretically be possible to recovery electrical energy out of the irrigation season. However, very few Calabrian WUAs have currently built SHPP in their irrigation networks and thus in this region the potential energy is practically fully lost. A previous study (Zema et al., 2016) proposed an original and simple model to site turbines and size their power output as well as to evaluate profits of SHPP in collective irrigation networks. Applying this model at regional scale, this paper estimates the theoretical energy production and the economic performances of SHPP installed in collective irrigation networks of Calabrian WUAs. In more detail, based on digital terrain models processed by GIS and few parameters of the water networks, for each SHPP the model provides: (i) the electrical power output; (iii) the optimal water discharge; (ii) costs, revenues and profits. Moreover, the map of the theoretical energy production by SHPP in collective irrigation networks of Calabria was drawn. The total network length of the 103 water networks surveyed is equal to 414 km and the total geodetic head is 3157 m, of which 63% is lost due to hydraulic losses. Thus, a total power output of 19.4 MW could theoretically be installed. This would provide an annual energy production of 103 GWh, considering SHPPs in operation only out of the irrigation season. The single irrigation networks have a power output in the range 0.7 kW - 6.4 MW. However, the lowest SHPPs (that is, turbines with power output under 5 kW) have been neglected, because the annual profit is very low (on average less than 6%, Zema et al., 2016). On average each irrigation network provides an annual revenue from

  4. Collective learning for the emergence of social norms in networked multiagent systems.

    Science.gov (United States)

    Yu, Chao; Zhang, Minjie; Ren, Fenghui

    2014-12-01

    Social norms such as social rules and conventions play a pivotal role in sustaining system order by regulating and controlling individual behaviors toward a global consensus in large-scale distributed systems. Systematic studies of efficient mechanisms that can facilitate the emergence of social norms enable us to build and design robust distributed systems, such as electronic institutions and norm-governed sensor networks. This paper studies the emergence of social norms via learning from repeated local interactions in networked multiagent systems. A collective learning framework, which imitates the opinion aggregation process in human decision making, is proposed to study the impact of agent local collective behaviors on the emergence of social norms in a number of different situations. In the framework, each agent interacts repeatedly with all of its neighbors. At each step, an agent first takes a best-response action toward each of its neighbors and then combines all of these actions into a final action using ensemble learning methods. Extensive experiments are carried out to evaluate the framework with respect to different network topologies, learning strategies, numbers of actions, influences of nonlearning agents, and so on. Experimental results reveal some significant insights into the manipulation and control of norm emergence in networked multiagent systems achieved through local collective behaviors.

  5. Announced document collection of the 3rd information exchange meeting on radioactive waste disposal research network

    International Nuclear Information System (INIS)

    2008-03-01

    The 3rd meeting on 'Radioactive Waste Disposal Research Network' was held at the Ricotti techno community square of JAEA on September 3 and 4, 2007. The 'Radioactive Waste Disposal Research Network' was established in Interorganization Atomic Energy Research Program under academic collaborative agreement between Japan Atomic Energy Agency and the University of Tokyo. The objective is to bring both research infrastructures and human expertise in Japan to an adequate performance level, thereby contributing to the development of the fundamental research area in the field of radioactive waste disposal. This lecture material is a collection of presentations and discussions during the information exchange meeting. (author)

  6. Joint Mobile Data Collection and Wireless Energy Transfer in Wireless Rechargeable Sensor Networks.

    Science.gov (United States)

    Zhong, Ping; Li, Ya-Ting; Liu, Wei-Rong; Duan, Gui-Hua; Chen, Ying-Wen; Xiong, Neal

    2017-08-16

    In wireless rechargeable sensor networks (WRSNs), there is a way to use mobile vehicles to charge node and collect data. It is a rational pattern to use two types of vehicles, one is for energy charging, and the other is for data collecting. These two types of vehicles, data collection vehicles (DCVs) and wireless charging vehicles (WCVs), are employed to achieve high efficiency in both data gathering and energy consumption. To handle the complex scheduling problem of multiple vehicles in large-scale networks, a twice-partition algorithm based on center points is proposed to divide the network into several parts. In addition, an anchor selection algorithm based on the tradeoff between neighbor amount and residual energy, named AS-NAE, is proposed to collect the zonal data. It can reduce the data transmission delay and the energy consumption for DCVs' movement in the zonal. Besides, we design an optimization function to achieve maximum data throughput by adjusting data rate and link rate of each node. Finally, the effectiveness of proposed algorithm is validated by numerical simulation results in WRSNs.

  7. Informal networks and resilience to climate change impacts: A collective approach to index insurance

    DEFF Research Database (Denmark)

    Trærup, Sara Lærke Meltofte

    2012-01-01

    This article contributes to the understanding of how to proceed with the development of index-insurance in order to reach extended population coverage with the insurance. The approach is applied to an example from a region in Tanzania. One of the main coping strategies that resource-poor households...... networks become insufficient since the majority of risk-sharers will be affected by the shock at the same time. This paper proposes a collective approach to index-insurance in which the members of an informal network will be insured as one insurance taker. The paper raises a conceptual argument...... that targeting households through existing informal networks will remove a number of prevailing barriers to the takeup of insurance and consequently the approach has the potential to increase households’ resilience to climate change impacts. The policy implications of the conclusions are significant since...

  8. Solution of weakly compressible isothermal flow in landfill gas collection networks

    Energy Technology Data Exchange (ETDEWEB)

    Nec, Y [Thompson Rivers University, Kamloops, British Columbia (Canada); Huculak, G, E-mail: cranberryana@gmail.com, E-mail: greg@gnhconsulting.ca [GNH Consulting, Delta, British Columbia (Canada)

    2017-12-15

    Pipe networks collecting gas in sanitary landfills operate under the regime of a weakly compressible isothermal flow of ideal gas. The effect of compressibility has been traditionally neglected in this application in favour of simplicity, thereby creating a conceptual incongruity between the flow equations and thermodynamic equation of state. Here the flow is solved by generalisation of the classic Darcy–Weisbach equation for an incompressible steady flow in a pipe to an ordinary differential equation, permitting continuous variation of density, viscosity and related fluid parameters, as well as head loss or gain due to gravity, in isothermal flow. The differential equation is solved analytically in the case of ideal gas for a single edge in the network. Thereafter the solution is used in an algorithm developed to construct the flow equations automatically for a network characterised by an incidence matrix, and determine pressure distribution, flow rates and all associated parameters therein. (paper)

  9. Solution of weakly compressible isothermal flow in landfill gas collection networks

    Science.gov (United States)

    Nec, Y.; Huculak, G.

    2017-12-01

    Pipe networks collecting gas in sanitary landfills operate under the regime of a weakly compressible isothermal flow of ideal gas. The effect of compressibility has been traditionally neglected in this application in favour of simplicity, thereby creating a conceptual incongruity between the flow equations and thermodynamic equation of state. Here the flow is solved by generalisation of the classic Darcy-Weisbach equation for an incompressible steady flow in a pipe to an ordinary differential equation, permitting continuous variation of density, viscosity and related fluid parameters, as well as head loss or gain due to gravity, in isothermal flow. The differential equation is solved analytically in the case of ideal gas for a single edge in the network. Thereafter the solution is used in an algorithm developed to construct the flow equations automatically for a network characterised by an incidence matrix, and determine pressure distribution, flow rates and all associated parameters therein.

  10. Solution of weakly compressible isothermal flow in landfill gas collection networks

    International Nuclear Information System (INIS)

    Nec, Y; Huculak, G

    2017-01-01

    Pipe networks collecting gas in sanitary landfills operate under the regime of a weakly compressible isothermal flow of ideal gas. The effect of compressibility has been traditionally neglected in this application in favour of simplicity, thereby creating a conceptual incongruity between the flow equations and thermodynamic equation of state. Here the flow is solved by generalisation of the classic Darcy–Weisbach equation for an incompressible steady flow in a pipe to an ordinary differential equation, permitting continuous variation of density, viscosity and related fluid parameters, as well as head loss or gain due to gravity, in isothermal flow. The differential equation is solved analytically in the case of ideal gas for a single edge in the network. Thereafter the solution is used in an algorithm developed to construct the flow equations automatically for a network characterised by an incidence matrix, and determine pressure distribution, flow rates and all associated parameters therein. (paper)

  11. Model-free inference of direct network interactions from nonlinear collective dynamics.

    Science.gov (United States)

    Casadiego, Jose; Nitzan, Mor; Hallerberg, Sarah; Timme, Marc

    2017-12-19

    The topology of interactions in network dynamical systems fundamentally underlies their function. Accelerating technological progress creates massively available data about collective nonlinear dynamics in physical, biological, and technological systems. Detecting direct interaction patterns from those dynamics still constitutes a major open problem. In particular, current nonlinear dynamics approaches mostly require to know a priori a model of the (often high dimensional) system dynamics. Here we develop a model-independent framework for inferring direct interactions solely from recording the nonlinear collective dynamics generated. Introducing an explicit dependency matrix in combination with a block-orthogonal regression algorithm, the approach works reliably across many dynamical regimes, including transient dynamics toward steady states, periodic and non-periodic dynamics, and chaos. Together with its capabilities to reveal network (two point) as well as hypernetwork (e.g., three point) interactions, this framework may thus open up nonlinear dynamics options of inferring direct interaction patterns across systems where no model is known.

  12. Branch-Based Centralized Data Collection for Smart Grids Using Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Kwangsoo Kim

    2015-05-01

    Full Text Available A smart grid is one of the most important applications in smart cities. In a smart grid, a smart meter acts as a sensor node in a sensor network, and a central device collects power usage from every smart meter. This paper focuses on a centralized data collection problem of how to collect every power usage from every meter without collisions in an environment in which the time synchronization among smart meters is not guaranteed. To solve the problem, we divide a tree that a sensor network constructs into several branches. A conflict-free query schedule is generated based on the branches. Each power usage is collected according to the schedule. The proposed method has important features: shortening query processing time and avoiding collisions between a query and query responses. We evaluate this method using the ns-2 simulator. The experimental results show that this method can achieve both collision avoidance and fast query processing at the same time. The success rate of data collection at a sink node executing this method is 100%. Its running time is about 35 percent faster than that of the round-robin method, and its memory size is reduced to about 10% of that of the depth-first search method.

  13. Branch-based centralized data collection for smart grids using wireless sensor networks.

    Science.gov (United States)

    Kim, Kwangsoo; Jin, Seong-il

    2015-05-21

    A smart grid is one of the most important applications in smart cities. In a smart grid, a smart meter acts as a sensor node in a sensor network, and a central device collects power usage from every smart meter. This paper focuses on a centralized data collection problem of how to collect every power usage from every meter without collisions in an environment in which the time synchronization among smart meters is not guaranteed. To solve the problem, we divide a tree that a sensor network constructs into several branches. A conflict-free query schedule is generated based on the branches. Each power usage is collected according to the schedule. The proposed method has important features: shortening query processing time and avoiding collisions between a query and query responses. We evaluate this method using the ns-2 simulator. The experimental results show that this method can achieve both collision avoidance and fast query processing at the same time. The success rate of data collection at a sink node executing this method is 100%. Its running time is about 35 percent faster than that of the round-robin method, and its memory size is reduced to about 10% of that of the depth-first search method.

  14. Competition between Local Collisions and Collective Hydrodynamic Feedback Controls Traffic Flows in Microfluidic Networks

    Science.gov (United States)

    Belloul, M.; Engl, W.; Colin, A.; Panizza, P.; Ajdari, A.

    2009-05-01

    By studying the repartition of monodisperse droplets at a simple T junction, we show that the traffic of discrete fluid systems in microfluidic networks results from two competing mechanisms, whose significance is driven by confinement. Traffic is dominated by collisions occurring at the junction for small droplets and by collective hydrodynamic feedback for large ones. For each mechanism, we present simple models in terms of the pertinent dimensionless parameters of the problem.

  15. Raging Against the Machine: Network Gatekeeping and Collective Action on Social Media Platforms

    Directory of Open Access Journals (Sweden)

    Sarah Myers West

    2017-09-01

    Full Text Available Social media platforms act as networked gatekeepers—by ranking, channeling, promoting, censoring, and deleting content they hold power to facilitate or hinder information flows. One of the mechanisms they use is content moderation, or the enforcement of which content is allowed or disallowed on the platform. Though content moderation relies on users’ labor to identify content to delete, users have little capacity to influence content policies or enforcement. Despite this, some social media users are turning to collective action campaigns, redirecting information flows by subverting the activities of moderators, raising the visibility of otherwise hidden moderation practices, and organizing constituencies in opposition to content policies. Drawing on the example of the campaign to change Facebook’s nudity policy, this paper examines the strategies and tactics of users turning to collective action, considering which factors are most influential in determining the success or failure of a campaign. It finds that network gatekeeping salience is a good model for assessing which collective action efforts are most likely to be effective in achieving individual user goals. This indicates that the users who are already most able to harness the attention economy of social media platforms are more likely to successfully navigate the content moderation process. The analysis concludes by attending to what users might learn from the dynamics of network gatekeeping as they seek to resist the asymmetrical power relations of platforms.

  16. NETWORK FOLKLORE AND ITS ROLE IN THE FORMATION OF A COLLECTIVE COGNITIVE SPACE

    Directory of Open Access Journals (Sweden)

    Anastasija Belovodskaja

    2014-04-01

    Full Text Available The global implementation of information-communicative technologies into every sphere of human activity is being accompanied by the emergence of new forms of communication, le­ading to inevitable changes in the means of both the representation and reception of information. In this respect, the field of interest encompasses research into modern anonymous network creative writing, which, as a result of the technological qualities of the Internet space, produces such texts that require particular skills in both comprehension and reproduction. In turn, the products of network folklore, as they spontaneously spread on the Internet, acquire the status of particular signs of a precedent nature. At the same time, the very nature of anonymous network creative writing—amusing and colloquial—raises the attractiveness of such texts and facilitates their reception, allowing them to be used for manipulative aims. The fact that such network folklore can influence the process of idea-formation in society is predetermined by the fact that, by definition, it is the milieu where collective representations are condensed and transmitted. Thus, network folklore is in the focus of attention not only in folklore studies, but is extremely topical for research in such fields as cognitive science, linguistic-cultural studies, public relations, speech effect, and any others which take interest in the processes of keeping, receiving, and transmitting information.

  17. Multi-Source Cooperative Data Collection with a Mobile Sink for the Wireless Sensor Network.

    Science.gov (United States)

    Han, Changcai; Yang, Jinsheng

    2017-10-30

    The multi-source cooperation integrating distributed low-density parity-check codes is investigated to jointly collect data from multiple sensor nodes to the mobile sink in the wireless sensor network. The one-round and two-round cooperative data collection schemes are proposed according to the moving trajectories of the sink node. Specifically, two sparse cooperation models are firstly formed based on geographical locations of sensor source nodes, the impairment of inter-node wireless channels and moving trajectories of the mobile sink. Then, distributed low-density parity-check codes are devised to match the directed graphs and cooperation matrices related with the cooperation models. In the proposed schemes, each source node has quite low complexity attributed to the sparse cooperation and the distributed processing. Simulation results reveal that the proposed cooperative data collection schemes obtain significant bit error rate performance and the two-round cooperation exhibits better performance compared with the one-round scheme. The performance can be further improved when more source nodes participate in the sparse cooperation. For the two-round data collection schemes, the performance is evaluated for the wireless sensor networks with different moving trajectories and the variant data sizes.

  18. Team performance and collective efficacy in the dynamic psychology of competitive team: a Bayesian network analysis.

    Science.gov (United States)

    Fuster-Parra, P; García-Mas, A; Ponseti, F J; Leo, F M

    2015-04-01

    The purpose of this paper was to discover the relationships among 22 relevant psychological features in semi-professional football players in order to study team's performance and collective efficacy via a Bayesian network (BN). The paper includes optimization of team's performance and collective efficacy using intercausal reasoning pattern which constitutes a very common pattern in human reasoning. The BN is used to make inferences regarding our problem, and therefore we obtain some conclusions; among them: maximizing the team's performance causes a decrease in collective efficacy and when team's performance achieves the minimum value it causes an increase in moderate/high values of collective efficacy. Similarly, we may reason optimizing team collective efficacy instead. It also allows us to determine the features that have the strongest influence on performance and which on collective efficacy. From the BN two different coaching styles were differentiated taking into account the local Markov property: training leadership and autocratic leadership. Copyright © 2014 Elsevier B.V. All rights reserved.

  19. Interaction networks, ecological stability, and collective antibiotic tolerance in polymicrobial infections

    Science.gov (United States)

    de Vos, Marjon G. J.; Bollenbach, Tobias

    2017-01-01

    Polymicrobial infections constitute small ecosystems that accommodate several bacterial species. Commonly, these bacteria are investigated in isolation. However, it is unknown to what extent the isolates interact and whether their interactions alter bacterial growth and ecosystem resilience in the presence and absence of antibiotics. We quantified the complete ecological interaction network for 72 bacterial isolates collected from 23 individuals diagnosed with polymicrobial urinary tract infections and found that most interactions cluster based on evolutionary relatedness. Statistical network analysis revealed that competitive and cooperative reciprocal interactions are enriched in the global network, while cooperative interactions are depleted in the individual host community networks. A population dynamics model parameterized by our measurements suggests that interactions restrict community stability, explaining the observed species diversity of these communities. We further show that the clinical isolates frequently protect each other from clinically relevant antibiotics. Together, these results highlight that ecological interactions are crucial for the growth and survival of bacteria in polymicrobial infection communities and affect their assembly and resilience. PMID:28923953

  20. The art of collecting experimental data internationally: EXFOR, CINDA and the NRDC network

    International Nuclear Information System (INIS)

    Henriksson, H.; Schwerer, O.; Rochman, D.; Mikhaylyukova, M.V.; Otuka, N.

    2008-01-01

    The world-wide network of nuclear reaction data centres (NRDC) has, for about 40 years, provided data services to the scientific community. This network covers all types of nuclear reaction data, including neutron-induced, charged-particle-induced, and photonuclear data, used in a wide range of applications, such as fission reactors, accelerator driven systems, fusion facilities, nuclear medicine, materials analysis, environmental monitoring, and basic research. The now 13 nuclear data centres included in the NRDC are dividing the efforts of compilation and distribution for particular types of reactions and/or geographic regions all over the world. A central activity of the network is the collection and compilation of experimental nuclear reaction data and the related bibliographic information in the EXFOR and CINDA databases. Many of the individual data centres also distribute other types of nuclear data information, including evaluated data libraries, nuclear structure and decay data, and nuclear data reports. The network today ensures the world-wide transfer of information and coordinated evolution of an important source of nuclear data for current and future nuclear applications. (authors)

  1. THE ART OF COLLECTING EXPERIMENTAL DATA INTERNATIONALLY: EXFOR, CINDA AND THE NRDC NETWORK

    International Nuclear Information System (INIS)

    HENRIKSSON, H.; SCHWERER, O.; ROCHMAN, D.; MIKHAYLYUKOVA, M.V.; OTUKA, N.

    2007-01-01

    The world-wide network of nuclear reaction data centers (NRDC) has, for about 40 years, provided data services to the scientific community. This network covers all types of nuclear reaction data, including neutron-induced, charged-particle-induced, and photonuclear data, used in a wide range of applications, such as fission reactors, accelerator driven systems, fusion facilities, nuclear medicine, materials analysis, environmental monitoring, and basic research. The now 13 nuclear data centers included in the NRDC are dividing the efforts of compilation and distribution for particular types of reactions and/or geographic regions all over the world. A central activity of the network is the collection and compilation of experimental nuclear reaction data and the related bibliographic information in the EXFOR and CINDA databases. Many of the individual data centers also distribute other types of nuclear data information, including evaluated data libraries, nuclear structure and decay data, and nuclear data reports. The network today ensures the world-wide transfer of information and coordinated evolution of an important source of nuclear data for current and future nuclear applications

  2. Collective Phenomena Emerging from the Interactions between Dynamical Processes in Multiplex Networks.

    Science.gov (United States)

    Nicosia, Vincenzo; Skardal, Per Sebastian; Arenas, Alex; Latora, Vito

    2017-03-31

    We introduce a framework to intertwine dynamical processes of different nature, each with its own distinct network topology, using a multilayer network approach. As an example of collective phenomena emerging from the interactions of multiple dynamical processes, we study a model where neural dynamics and nutrient transport are bidirectionally coupled in such a way that the allocation of the transport process at one layer depends on the degree of synchronization at the other layer, and vice versa. We show numerically, and we prove analytically, that the multilayer coupling induces a spontaneous explosive synchronization and a heterogeneous distribution of allocations, otherwise not present in the two systems considered separately. Our framework can find application to other cases where two or more dynamical processes such as synchronization, opinion formation, information diffusion, or disease spreading, are interacting with each other.

  3. Wireless Visual Sensor Network Robots- Based for the Emulation of Collective Behavior

    Directory of Open Access Journals (Sweden)

    Fredy Hernán Martinez Sarmiento

    2012-03-01

    Full Text Available We consider the problem of bacterial quorum sensing emulate on small mobile robots. Robots that reflect the behavior of bacteria are designed as mobile wireless camera nodes. They are able to structure a dynamic wireless sensor network. Emulated behavior corresponds to a simplification of bacterial quorum sensing, where the action of a network node is conditioned by the population density of robots(nodes in a given area. The population density reading is done visually using a camera. The robot makes an estimate of the population density of the images, and acts according to this information. The operation of the camera is done with a custom firmware, reducing the complexity of the node without loss of performance. It was noted the route planning and the collective behavior of robots without the use of any other external or local communication. Neither was it necessary to develop a model system, precise state estimation or state feedback.

  4. Research on the Application of Wireless Network in Collecting Road Traffic Information

    Institute of Scientific and Technical Information of China (English)

    DU Hui-jiang

    2015-01-01

    Due to the characteristics of variability and dispersion in traffic information, to get the reliable real-time traffic information has been a bottleneck in the development of intelligent transportation systems. However, with the development of wireless network technology and mobile Internet, the mobile phones are rapidly developed and more popular, so it is possible to get road traffic information by locating the mobile phones in vehicles. The system structure for the road traffic information collection is designed based on wireless network and mobile phones in vehicles, and the vehicle recognition and its information computation methods are given and discussed. Also the simulation is done for vehicle recognition and computation based on fuzzy cluster analysis method and the results are obtained and analyzed.

  5. Collective Phenomena Emerging from the Interactions between Dynamical Processes in Multiplex Networks

    Science.gov (United States)

    Nicosia, Vincenzo; Skardal, Per Sebastian; Arenas, Alex; Latora, Vito

    2017-03-01

    We introduce a framework to intertwine dynamical processes of different nature, each with its own distinct network topology, using a multilayer network approach. As an example of collective phenomena emerging from the interactions of multiple dynamical processes, we study a model where neural dynamics and nutrient transport are bidirectionally coupled in such a way that the allocation of the transport process at one layer depends on the degree of synchronization at the other layer, and vice versa. We show numerically, and we prove analytically, that the multilayer coupling induces a spontaneous explosive synchronization and a heterogeneous distribution of allocations, otherwise not present in the two systems considered separately. Our framework can find application to other cases where two or more dynamical processes such as synchronization, opinion formation, information diffusion, or disease spreading, are interacting with each other.

  6. Integrated forward/reverse logistics network design under uncertainty with pricing for collection of used products

    DEFF Research Database (Denmark)

    Fattahi, Mohammad; Govindan, Kannan

    2017-01-01

    This paper addresses design and planning of an integrated forward/reverse logistics network over a planning horizon with multiple tactical periods. In the network, demand for new products and potential return of used products are stochastic. Furthermore, collection amounts of used products...... with different quality levels are assumed dependent on offered acquisition prices to customer zones. A uniform distribution function defines the expected price of each customer zone for one unit of each used product. Using two-stage stochastic programming, a mixed-integer linear programming model is proposed....... To cope with demand and potential return uncertainty, Latin Hypercube Sampling method is applied to generate fan of scenarios and then, backward scenario reduction technique is used to reduce the number of scenarios. Due to the problem complexity, a novel simulation-based simulated annealing algorithm...

  7. Research on Factors Influencing Municipal Household Solid Waste Separate Collection: Bayesian Belief Networks

    Directory of Open Access Journals (Sweden)

    Zhujie Chu

    2016-02-01

    Full Text Available Municipal household solid waste (MHSW has become a serious problem in China over the course of the last two decades, resulting in significant side effects to the environment. Therefore, effective management of MHSW has attracted wide attention from both researchers and practitioners. Separate collection, the first and crucial step to solve the MHSW problem, however, has not been thoroughly studied to date. An empirical survey has been conducted among 387 households in Harbin, China in this study. We use Bayesian Belief Networks model to determine the influencing factors on separate collection. Four types of factors are identified, including political, economic, social cultural and technological based on the PEST (political, economic, social and technological analytical method. In addition, we further analyze the influential power of different factors, based on the network structure and probability changes obtained by Netica software. Results indicate that technological dimension has the greatest impact on MHSW separate collection, followed by the political dimension and economic dimension; social cultural dimension impacts MHSW the least.

  8. Addressing the Issue of Routing Unfairness in Opportunistic Backhaul Networks for Collecting Sensed Data

    Directory of Open Access Journals (Sweden)

    Tekenate E. Amah

    2017-12-01

    Full Text Available Widely deploying sensors in the environment and embedding them in physical objects is a crucial step towards realizing smart and sustainable cities. To cope with rising resource demands and limited budgets, opportunistic networks (OppNets offer a scalable backhaul option for collecting delay-tolerant data from sensors to gateways in order to enable efficient urban operations and services. While pervasive devices such as smartphones and tablets contribute significantly to the scalability of OppNets, closely following human movement patterns and social structure introduces network characteristics that pose routing challenges. Our study on the impact of these characteristics reveals that existing routing protocols subject a key set of devices to higher resource consumption, to which their users may respond by withdrawing participation. Unfortunately, existing solutions addressing this unfairness do not guarantee achievable throughput since they are not specifically designed for sensed data collection scenarios. Based on concepts derived from the study, we suggest design guidelines for adapting applicable routing protocols to sensed data collection scenarios. We also follow our design guidelines to propose the Fair Locality Aware Routing (FLARoute technique. Evaluating FLARoute within an existing routing protocol confirms improved fairness and throughput under conditions that compromise the performance of existing solutions.

  9. The Impact of Message Replication on the Performance of Opportunistic Networks for Sensed Data Collection

    Directory of Open Access Journals (Sweden)

    Tekenate E. Amah

    2017-11-01

    Full Text Available Opportunistic networks (OppNets provide a scalable solution for collecting delay‑tolerant data from sensors for their respective gateways. Portable handheld user devices contribute significantly to the scalability of OppNets since their number increases according to user population and they closely follow human movement patterns. Hence, OppNets for sensed data collection are characterised by high node population and degrees of spatial locality inherent to user movement. We study the impact of these characteristics on the performance of existing OppNet message replication techniques. Our findings reveal that the existing replication techniques are not specifically designed to cope with these characteristics. This raises concerns regarding excessive message transmission overhead and throughput degradations due to resource constraints and technological limitations associated with portable handheld user devices. Based on concepts derived from the study, we suggest design guidelines to augment existing message replication techniques. We also follow our design guidelines to propose a message replication technique, namely Locality Aware Replication (LARep. Simulation results show that LARep achieves better network performance under high node population and degrees of spatial locality as compared with existing techniques.

  10. Collective firing regularity of a scale-free Hodgkin–Huxley neuronal network in response to a subthreshold signal

    Energy Technology Data Exchange (ETDEWEB)

    Yilmaz, Ergin, E-mail: erginyilmaz@yahoo.com [Department of Biomedical Engineering, Engineering Faculty, Bülent Ecevit University, 67100 Zonguldak (Turkey); Ozer, Mahmut [Department of Electrical and Electronics Engineering, Engineering Faculty, Bülent Ecevit University, 67100 Zonguldak (Turkey)

    2013-08-01

    We consider a scale-free network of stochastic HH neurons driven by a subthreshold periodic stimulus and investigate how the collective spiking regularity or the collective temporal coherence changes with the stimulus frequency, the intrinsic noise (or the cell size), the network average degree and the coupling strength. We show that the best temporal coherence is obtained for a certain level of the intrinsic noise when the frequencies of the external stimulus and the subthreshold oscillations of the network elements match. We also find that the collective regularity exhibits a resonance-like behavior depending on both the coupling strength and the network average degree at the optimal values of the stimulus frequency and the cell size, indicating that the best temporal coherence also requires an optimal coupling strength and an optimal average degree of the connectivity.

  11. Social network sites as a mode to collect health data: a systematic review.

    Science.gov (United States)

    Alshaikh, Fahdah; Ramzan, Farzan; Rawaf, Salman; Majeed, Azeem

    2014-07-14

    To date, health research literature has focused on social network sites (SNS) either as tools to deliver health care, to study the effect of these networks on behavior, or to analyze Web health content. Less is known about the effectiveness of these sites as a method for collecting data for health research and the means to use such powerful tools in health research. The objective of this study was to systematically review the available literature and explore the use of SNS as a mode of collecting data for health research. The review aims to answer four questions: Does health research employ SNS as method for collecting data? Is data quality affected by the mode of data collection? What types of participants were reached by SNS? What are the strengths and limitations of SNS? The literature was reviewed systematically in March 2013 by searching the databases MEDLINE, Embase, and PsycINFO, using the Ovid and PubMed interface from 1996 to the third week of March 2013. The search results were examined by 2 reviewers, and exclusion, inclusion, and quality assessment were carried out based on a pre-set protocol. The inclusion criteria were met by 10 studies and results were analyzed descriptively to answer the review questions. There were four main results. (1) SNS have been used as a data collection tool by health researchers; all but 1 of the included studies were cross-sectional and quantitative. (2) Data quality indicators that were reported include response rate, cost, timeliness, missing data/completion rate, and validity. However, comparison was carried out only for response rate and cost as it was unclear how other reported indicators were measured. (3) The most targeted population were females and younger people. (4) All studies stated that SNS is an effective recruitment method but that it may introduce a sampling bias. SNS has a role in health research, but we need to ascertain how to use it effectively without affecting the quality of research. The field of

  12. A cost-effective traffic data collection system based on the iDEN mobile telecommunication network.

    Science.gov (United States)

    2008-10-01

    This report describes a cost-effective data collection system for Caltrans 170 traffic signal : controller. The data collection system is based on TCP/IP communication over existing : low-cost mobile communication networks and Motorola iDEN1 mobile...

  13. A Structure Fidelity Approach for Big Data Collection in Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Mou Wu

    2014-12-01

    Full Text Available One of the most widespread and important applications in wireless sensor networks (WSNs is the continuous data collection, such as monitoring the variety of ambient temperature and humidity. Due to the sensor nodes with a limited energy supply, the reduction of energy consumed in the continuous observation of physical phenomenon plays a significant role in extending the lifetime of WSNs. However, the high redundancy of sensing data leads to great waste of energy as a result of over-deployed sensor nodes. In this paper, we develop a structure fidelity data collection (SFDC framework leveraging the spatial correlations between nodes to reduce the number of the active sensor nodes while maintaining the low structural distortion of the collected data. A structural distortion based on the image quality assessment approach is used to perform the nodes work/sleep scheduling, such that the number of the working nodes is reduced while the remainder of nodes can be put into the low-power sleep mode during the sampling period. The main contribution of SFDC is to provide a unique perspective on how to maintain the data fidelity in term of structural similarity in the continuous sensing applications for WSNs. The simulation results based on synthetic and real world datasets verify the effectiveness of SFDC framework both on energy saving and data fidelity.

  14. Agroecology in Europe: Research, Education, Collective Action Networks, and Alternative Food Systems

    Directory of Open Access Journals (Sweden)

    Alexander Wezel

    2018-04-01

    Full Text Available Agroecology is considered with different focus and weight in different parts of the world as a social and political movement, as science, and as practice. Despite its multitude of definitions, agroecology has begun in Europe to develop in different regional, national and continental networks of researchers, practitioners, advocates and movements. However, there is a lack of a comprehensive overview about these different developments and networks. Therefore, this paper attempts to document and provide a mapping of the development of European agroecology in its diverse forms. Through a literature review, interviews, active conference participation, and an extensive internet search we have collected information about the current state and development of agroecology in Europe. Agroecological research and higher education exist more in western and northern Europe, but farm schools and farmer-to-farmer training are also present in other regions. Today a large variety of topics are studied at research institutions. There is an increasing number of bottom-up agroecological initiatives and national or continental networks and movements. Important movements are around food sovereignty, access to land and seeds. Except for France, there are very few concrete policies for agroecology in Europe. Agroecology is increasingly linked to different fields of agri-food systems. This includes Community Supported Agriculture systems, but also agroecological territories, and some examples of labelling products. To amplify agroecology in Europe in the coming years, policy development will be crucial and proponents of agroecology must join forces and work hand-in-hand with the many stakeholders engaged in initiatives to develop more sustainable agriculture and food systems.

  15. A Comprehensive Study of Data Collection Schemes Using Mobile Sinks in Wireless Sensor Networks

    Science.gov (United States)

    Khan, Abdul Waheed; Abdullah, Abdul Hanan; Anisi, Mohammad Hossein; Bangash, Javed Iqbal

    2014-01-01

    Recently sink mobility has been exploited in numerous schemes to prolong the lifetime of wireless sensor networks (WSNs). Contrary to traditional WSNs where sensory data from sensor field is ultimately sent to a static sink, mobile sink-based approaches alleviate energy-holes issues thereby facilitating balanced energy consumption among nodes. In mobility scenarios, nodes need to keep track of the latest location of mobile sinks for data delivery. However, frequent propagation of sink topological updates undermines the energy conservation goal and therefore should be controlled. Furthermore, controlled propagation of sinks' topological updates affects the performance of routing strategies thereby increasing data delivery latency and reducing packet delivery ratios. This paper presents a taxonomy of various data collection/dissemination schemes that exploit sink mobility. Based on how sink mobility is exploited in the sensor field, we classify existing schemes into three classes, namely path constrained, path unconstrained, and controlled sink mobility-based schemes. We also organize existing schemes based on their primary goals and provide a comparative study to aid readers in selecting the appropriate scheme in accordance with their particular intended applications and network dynamics. Finally, we conclude our discussion with the identification of some unresolved issues in pursuit of data delivery to a mobile sink. PMID:24504107

  16. Advanced Soil Moisture Network Technologies; Developments in Collecting in situ Measurements for Remote Sensing Missions

    Science.gov (United States)

    Moghaddam, M.; Silva, A. R. D.; Akbar, R.; Clewley, D.

    2015-12-01

    The Soil moisture Sensing Controller And oPtimal Estimator (SoilSCAPE) wireless sensor network has been developed to support Calibration and Validation activities (Cal/Val) for large scale soil moisture remote sensing missions (SMAP and AirMOSS). The technology developed here also readily supports small scale hydrological studies by providing sub-kilometer widespread soil moisture observations. An extensive collection of semi-sparse sensor clusters deployed throughout north-central California and southern Arizona provide near real time soil moisture measurements. Such a wireless network architecture, compared to conventional single points measurement profiles, allows for significant and expanded soil moisture sampling. The work presented here aims at discussing and highlighting novel and new technology developments which increase in situ soil moisture measurements' accuracy, reliability, and robustness with reduced data delivery latency. High efficiency and low maintenance custom hardware have been developed and in-field performance has been demonstrated for a period of three years. The SoilSCAPE technology incorporates (a) intelligent sensing to prevent erroneous measurement reporting, (b) on-board short term memory for data redundancy, (c) adaptive scheduling and sampling capabilities to enhance energy efficiency. A rapid streamlined data delivery architecture openly provides distribution of in situ measurements to SMAP and AirMOSS cal/val activities and other interested parties.

  17. Spatial-Temporal Data Collection with Compressive Sensing in Mobile Sensor Networks.

    Science.gov (United States)

    Zheng, Haifeng; Li, Jiayin; Feng, Xinxin; Guo, Wenzhong; Chen, Zhonghui; Xiong, Neal

    2017-11-08

    Compressive sensing (CS) provides an energy-efficient paradigm for data gathering in wireless sensor networks (WSNs). However, the existing work on spatial-temporal data gathering using compressive sensing only considers either multi-hop relaying based or multiple random walks based approaches. In this paper, we exploit the mobility pattern for spatial-temporal data collection and propose a novel mobile data gathering scheme by employing the Metropolis-Hastings algorithm with delayed acceptance, an improved random walk algorithm for a mobile collector to collect data from a sensing field. The proposed scheme exploits Kronecker compressive sensing (KCS) for spatial-temporal correlation of sensory data by allowing the mobile collector to gather temporal compressive measurements from a small subset of randomly selected nodes along a random routing path. More importantly, from the theoretical perspective we prove that the equivalent sensing matrix constructed from the proposed scheme for spatial-temporal compressible signal can satisfy the property of KCS models. The simulation results demonstrate that the proposed scheme can not only significantly reduce communication cost but also improve recovery accuracy for mobile data gathering compared to the other existing schemes. In particular, we also show that the proposed scheme is robust in unreliable wireless environment under various packet losses. All this indicates that the proposed scheme can be an efficient alternative for data gathering application in WSNs .

  18. SCADA System for the Modeling and Optimization of Oil Collecting Pipeline Network: A Case Study of Hassi Messaoud Oilfield

    OpenAIRE

    M. Aouadj; F. Naceri; M. Touileb; D. Sellami; M. Boukhatem

    2015-01-01

    This study aims are data acquisition, control and online modeling of an oil collection pipeline network using a SCADA «Supervisory Control and Data Acquisition» system, allowing the optimization of this network in real time by creating more exact models of onsite facilities. Indeed, fast development of computing systems makes obsolete usage of old systems for which maintenance became more and more expensive and their performances don’t comply any more with modern company operations. SCADA sys...

  19. Network of Green Areas within Collective Housing Communities - Case Study from Timişoara, Romania

    Science.gov (United States)

    Branea, Ana-Maria; Stelian Găman, Marius; Bădescu, Ştefana

    2017-10-01

    Green areas have always been an essential feature of urban developments, improving the quality of life within a community, both from a social perspective - offering residents a place for relaxation and interaction, as well as from the point of view of disease prevention - improving the overall air quality, but also encouraging inhabitants to spend more time outside. The importance of these areas within a settlement further increases in the present-day context, in which the constant expansion of cities in their surrounding territory, phenomenon known as “urban sprawl”, gradually eliminates the natural green spaces and agricultural terrains from our landscape. This trend has devastating effects on the environment, as well as on the micro-climate of our settlements, characterized, in recent years, by the formation of heat islands within the built tissue. Moreover, the disappearance of natural green areas leads to the constant estrangement of the inhabitants, and especially of young generations, from the natural values and realities. It is thus more important than ever to ensure an adequate percentage of green areas for our cities, uniformly distributed within the urban tissue. Green belts, urban forests, parks, green squares or even urban gardens - all these entities play their parts within the urban green network, having certain radiuses of influence and attraction and thus occupying a specific position within the urban hierarchy. In Romania, the terrains left un-built between the collective housing buildings - or apartment blocks, erected during the communist administration and currently constituting public property, have a huge potential regarding the matter of urban greenery, being easily transformed into active and qualitative green areas. However, the local authorities lack the resources (both financial and in terms of human resources) to efficiently develop and then administrate these areas, which are consequently either abandoned, or used as illegal

  20. Searching for collective behavior in a large network of sensory neurons.

    Directory of Open Access Journals (Sweden)

    Gašper Tkačik

    2014-01-01

    Full Text Available Maximum entropy models are the least structured probability distributions that exactly reproduce a chosen set of statistics measured in an interacting network. Here we use this principle to construct probabilistic models which describe the correlated spiking activity of populations of up to 120 neurons in the salamander retina as it responds to natural movies. Already in groups as small as 10 neurons, interactions between spikes can no longer be regarded as small perturbations in an otherwise independent system; for 40 or more neurons pairwise interactions need to be supplemented by a global interaction that controls the distribution of synchrony in the population. Here we show that such "K-pairwise" models--being systematic extensions of the previously used pairwise Ising models--provide an excellent account of the data. We explore the properties of the neural vocabulary by: 1 estimating its entropy, which constrains the population's capacity to represent visual information; 2 classifying activity patterns into a small set of metastable collective modes; 3 showing that the neural codeword ensembles are extremely inhomogenous; 4 demonstrating that the state of individual neurons is highly predictable from the rest of the population, allowing the capacity for error correction.

  1. Collection, transfer and processing of information in systems of monitoring of objects based on wireless sensor networks

    Directory of Open Access Journals (Sweden)

    Sergievskiy Maxim

    2016-01-01

    Full Text Available Monitoring of the aircraft structures’ during the pre-fiight testing is a critical task of the aerospace industry. One of the most promising solutions, not yet widely applied, is continuous monitoring of aircraft structures using wireless sensor network technology. The brief summary of the proposed system is the following: special sensors send signals to the local motes (autonomous computing device equipped with a wireless transmitter. Information from motes is gathered by routers which then transfer the aggregated information to the datacenter. Applications of corporate network control and define flexible patterns for processing of the information received from sensors. This network structure allows to centralize data collection modes in the process of testing; implement continuous data collection at a defined frequency; process and display data in real-time.

  2. A Low Collision and High Throughput Data Collection Mechanism for Large-Scale Super Dense Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Chunyang Lei

    2016-07-01

    Full Text Available Super dense wireless sensor networks (WSNs have become popular with the development of Internet of Things (IoT, Machine-to-Machine (M2M communications and Vehicular-to-Vehicular (V2V networks. While highly-dense wireless networks provide efficient and sustainable solutions to collect precise environmental information, a new channel access scheme is needed to solve the channel collision problem caused by the large number of competing nodes accessing the channel simultaneously. In this paper, we propose a space-time random access method based on a directional data transmission strategy, by which collisions in the wireless channel are significantly decreased and channel utility efficiency is greatly enhanced. Simulation results show that our proposed method can decrease the packet loss rate to less than 2 % in large scale WSNs and in comparison with other channel access schemes for WSNs, the average network throughput can be doubled.

  3. A Low Collision and High Throughput Data Collection Mechanism for Large-Scale Super Dense Wireless Sensor Networks.

    Science.gov (United States)

    Lei, Chunyang; Bie, Hongxia; Fang, Gengfa; Gaura, Elena; Brusey, James; Zhang, Xuekun; Dutkiewicz, Eryk

    2016-07-18

    Super dense wireless sensor networks (WSNs) have become popular with the development of Internet of Things (IoT), Machine-to-Machine (M2M) communications and Vehicular-to-Vehicular (V2V) networks. While highly-dense wireless networks provide efficient and sustainable solutions to collect precise environmental information, a new channel access scheme is needed to solve the channel collision problem caused by the large number of competing nodes accessing the channel simultaneously. In this paper, we propose a space-time random access method based on a directional data transmission strategy, by which collisions in the wireless channel are significantly decreased and channel utility efficiency is greatly enhanced. Simulation results show that our proposed method can decrease the packet loss rate to less than 2 % in large scale WSNs and in comparison with other channel access schemes for WSNs, the average network throughput can be doubled.

  4. From Social Network (Centralized vs. Decentralized) to Collective Decision-Making (Unshared vs. Shared Consensus)

    OpenAIRE

    Sueur, Cédric; Deneubourg, Jean-Louis; Petit, Odile

    2012-01-01

    Relationships we have with our friends, family, or colleagues influence our personal decisions, as well as decisions we make together with others. As in human beings, despotism and egalitarian societies seem to also exist in animals. While studies have shown that social networks constrain many phenomena from amoebae to primates, we still do not know how consensus emerges from the properties of social networks in many biological systems. We created artificial social networks that represent the...

  5. Older adolescents' motivations for social network site use: the influence of gender, group identity, and collective self-esteem.

    Science.gov (United States)

    Barker, Valerie

    2009-04-01

    This study assessed motives for social network site (SNS) use, group belonging, collective self-esteem, and gender effects among older adolescents. Communication with peer group members was the most important motivation for SNS use. Participants high in positive collective self-esteem were strongly motivated to communicate with peer group via SNS. Females were more likely to report high positive collective self-esteem, greater overall use, and SNS use to communicate with peers. Females also posted higher means for group-in-self, passing time, and entertainment. Negative collective self-esteem correlated with social compensation, suggesting that those who felt negatively about their social group used SNS as an alternative to communicating with other group members. Males were more likely than females to report negative collective self-esteem and SNS use for social compensation and social identity gratifications.

  6. Auditing information structures in organizations: A review of data collection techniques for network analysis

    NARCIS (Netherlands)

    Koning, K.H.; de Jong, Menno D.T.

    2005-01-01

    Network analysis is one of the current techniques for investigating organizational communication. Despite the amount of how-to literature about using network analysis to assess information flows and relationships in organizations, little is known about the methodological strengths and weaknesses of

  7. Statistical indicators of collective behavior and functional clusters in gene networks of yeast

    Science.gov (United States)

    Živković, J.; Tadić, B.; Wick, N.; Thurner, S.

    2006-03-01

    We analyze gene expression time-series data of yeast (S. cerevisiae) measured along two full cell-cycles. We quantify these data by using q-exponentials, gene expression ranking and a temporal mean-variance analysis. We construct gene interaction networks based on correlation coefficients and study the formation of the corresponding giant components and minimum spanning trees. By coloring genes according to their cell function we find functional clusters in the correlation networks and functional branches in the associated trees. Our results suggest that a percolation point of functional clusters can be identified on these gene expression correlation networks.

  8. The data collection/data distribution center: building a sustainable African-American church-based research network.

    Science.gov (United States)

    Goldmon, Moses; Roberson, James T; Carey, Tim; Godley, Paul; Howard, Daniel L; Boyd, Carlton; Ammerman, Alice

    2008-01-01

    This article describes the Carolina-Shaw Partnership for the Elimination of Health Disparities efforts to engage a diverse group of Black churches in a sustainable network. We sought to develop a diverse network of 25 churches to work with the Carolina-Shaw Partnership to develop sustainable health disparities research, education, and intervention initiatives. Churches were selected based on location, pastoral buy-in, and capacity to engage. A purposive sampling technique was applied. (1) Collecting information on the location and characteristics of churches helps to identify and recruit churches that possess the desired qualities and characteristics. (2) The process used to identify, recruit, and select churches is time intensive. (3) The time, energy, and effort required managing an inter-institutional partnership and engage churches in health disparities research and interventions lends itself to sustainability. The development of a sustainable network of churches could lead to successful health disparities initiatives.

  9. The U.S. Culture Collection Network Responding to the Requirements of the Nagoya Protocol on Access and Benefit Sharing

    Directory of Open Access Journals (Sweden)

    Kevin McCluskey

    2017-08-01

    Full Text Available The U.S. Culture Collection Network held a meeting to share information about how culture collections are responding to the requirements of the recently enacted Nagoya Protocol on Access to Genetic Resources and the Fair and Equitable Sharing of Benefits Arising from their Utilization to the Convention on Biological Diversity (CBD. The meeting included representatives of many culture collections and other biological collections, the U.S. Department of State, U.S. Department of Agriculture, Secretariat of the CBD, interested scientific societies, and collection groups, including Scientific Collections International and the Global Genome Biodiversity Network. The participants learned about the policies of the United States and other countries regarding access to genetic resources, the definition of genetic resources, and the status of historical materials and genetic sequence information. Key topics included what constitutes access and how the CBD Access and Benefit-Sharing Clearing-House can help guide researchers through the process of obtaining Prior Informed Consent on Mutually Agreed Terms. U.S. scientists and their international collaborators are required to follow the regulations of other countries when working with microbes originally isolated outside the United States, and the local regulations required by the Nagoya Protocol vary by the country of origin of the genetic resource. Managers of diverse living collections in the United States described their holdings and their efforts to provide access to genetic resources. This meeting laid the foundation for cooperation in establishing a set of standard operating procedures for U.S. and international culture collections in response to the Nagoya Protocol.

  10. Analog-to-digital clinical data collection on networked workstations with graphic user interface.

    Science.gov (United States)

    Lunt, D

    1991-02-01

    An innovative respiratory examination system has been developed that combines physiological response measurement, real-time graphic displays, user-driven operating sequences, and networked file archiving and review into a scientific research and clinical diagnosis tool. This newly constructed computer network is being used to enhance the research center's ability to perform patient pulmonary function examinations. Respiratory data are simultaneously acquired and graphically presented during patient breathing maneuvers and rapidly transformed into graphic and numeric reports, suitable for statistical analysis or database access. The environment consists of the hardware (Macintosh computer, MacADIOS converters, analog amplifiers), the software (HyperCard v2.0, HyperTalk, XCMDs), and the network (AppleTalk, fileservers, printers) as building blocks for data acquisition, analysis, editing, and storage. System operation modules include: Calibration, Examination, Reports, On-line Help Library, Graphic/Data Editing, and Network Storage.

  11. Development of a System to Collect Social Network Data from College Students for Future Studies in Health Behavior and Academic Performance /

    OpenAIRE

    Lah, Mike Myoungwhan

    2013-01-01

    Researchers study social networks to understand how individuals with similar behavior form clusters, and what causes them to do so. Universities are interested in learning more about influential factors of student behavior, including the impact that their social networks have on these behaviors. We have done foundational work to collect a dataset about UCSD student social network data gathered from Facebook and academic data from the UCSD Registrar. Once complete, the social network portion o...

  12. The salience of social referents: a field experiment on collective norms and harassment behavior in a school social network.

    Science.gov (United States)

    Paluck, Elizabeth Levy; Shepherd, Hana

    2012-12-01

    Persistent, widespread harassment in schools can be understood as a product of collective school norms that deem harassment, and behavior allowing harassment to escalate, as typical and even desirable. Thus, one approach to reducing harassment is to change students' perceptions of these collective norms. Theory suggests that the public behavior of highly connected and chronically salient actors in a group, called social referents, may provide influential cues for individuals' perception of collective norms. Using repeated, complete social network surveys of a public high school, we demonstrate that changing the public behavior of a randomly assigned subset of student social referents changes their peers' perceptions of school collective norms and their harassment behavior. Social referents exert their influence over peers' perceptions of collective norms through the mechanism of everyday social interaction, particularly interaction that is frequent and personally motivated, in contrast to interaction shaped by institutional channels like shared classes. These findings clarify the development of collective social norms: They depend on certain patterns of and motivations for social interactions within groups across time, and are not static but constantly reshaped and reproduced through these interactions. Understanding this process creates opportunities for changing collective norms and behavior. (PsycINFO Database Record (c) 2012 APA, all rights reserved).

  13. Collective Influence of Multiple Spreaders Evaluated by Tracing Real Information Flow in Large-Scale Social Networks.

    Science.gov (United States)

    Teng, Xian; Pei, Sen; Morone, Flaviano; Makse, Hernán A

    2016-10-26

    Identifying the most influential spreaders that maximize information flow is a central question in network theory. Recently, a scalable method called "Collective Influence (CI)" has been put forward through collective influence maximization. In contrast to heuristic methods evaluating nodes' significance separately, CI method inspects the collective influence of multiple spreaders. Despite that CI applies to the influence maximization problem in percolation model, it is still important to examine its efficacy in realistic information spreading. Here, we examine real-world information flow in various social and scientific platforms including American Physical Society, Facebook, Twitter and LiveJournal. Since empirical data cannot be directly mapped to ideal multi-source spreading, we leverage the behavioral patterns of users extracted from data to construct "virtual" information spreading processes. Our results demonstrate that the set of spreaders selected by CI can induce larger scale of information propagation. Moreover, local measures as the number of connections or citations are not necessarily the deterministic factors of nodes' importance in realistic information spreading. This result has significance for rankings scientists in scientific networks like the APS, where the commonly used number of citations can be a poor indicator of the collective influence of authors in the community.

  14. Collective Influence of Multiple Spreaders Evaluated by Tracing Real Information Flow in Large-Scale Social Networks

    Science.gov (United States)

    Teng, Xian; Pei, Sen; Morone, Flaviano; Makse, Hernán A.

    2016-01-01

    Identifying the most influential spreaders that maximize information flow is a central question in network theory. Recently, a scalable method called “Collective Influence (CI)” has been put forward through collective influence maximization. In contrast to heuristic methods evaluating nodes’ significance separately, CI method inspects the collective influence of multiple spreaders. Despite that CI applies to the influence maximization problem in percolation model, it is still important to examine its efficacy in realistic information spreading. Here, we examine real-world information flow in various social and scientific platforms including American Physical Society, Facebook, Twitter and LiveJournal. Since empirical data cannot be directly mapped to ideal multi-source spreading, we leverage the behavioral patterns of users extracted from data to construct “virtual” information spreading processes. Our results demonstrate that the set of spreaders selected by CI can induce larger scale of information propagation. Moreover, local measures as the number of connections or citations are not necessarily the deterministic factors of nodes’ importance in realistic information spreading. This result has significance for rankings scientists in scientific networks like the APS, where the commonly used number of citations can be a poor indicator of the collective influence of authors in the community. PMID:27782207

  15. Pragmatism, persistence and patience: a user perspective on strategies for data collection using popular online social networks.

    Science.gov (United States)

    Mannix, Judy; Wilkes, Lesley; Daly, John

    2014-01-01

    The increasing pervasiveness of the internet and social networking globally presents new opportunities and challenges for empirical social science researchers including those in nursing. Developments in computer-mediated communication are not static and there is potential for further advances and innovation in research methods embracing this technology. The aim of this paper is to present a reflexive account and critique of the use of social media as a means of data collection in a study that sought to explore the aesthetics of clinical leadership in contemporary nursing. In doing so, comparisons are drawn from using Twitter, Facebook and e-learning announcements as methods of recruitment and subsequent data collection via an online survey. The pragmatics of the internet and online social networks as vehicles for data collection are discussed. While questions remain about best practice to safeguard the scientific integrity of these approaches and the researchers and research participants who choose to participate, the potential exists for researchers to enhance and expand research methods without compromising rigour and validity. In the interests of sharpening thinking about this means of data collection dialogue and debate are needed on a range of research aspects including but not limited to pragmatics, new requirements in research training and development, legal and ethical guidelines and strengths and limitations encountered.

  16. Annotating gene sets by mining large literature collections with protein networks.

    Science.gov (United States)

    Wang, Sheng; Ma, Jianzhu; Yu, Michael Ku; Zheng, Fan; Huang, Edward W; Han, Jiawei; Peng, Jian; Ideker, Trey

    2018-01-01

    Analysis of patient genomes and transcriptomes routinely recognizes new gene sets associated with human disease. Here we present an integrative natural language processing system which infers common functions for a gene set through automatic mining of the scientific literature with biological networks. This system links genes with associated literature phrases and combines these links with protein interactions in a single heterogeneous network. Multiscale functional annotations are inferred based on network distances between phrases and genes and then visualized as an ontology of biological concepts. To evaluate this system, we predict functions for gene sets representing known pathways and find that our approach achieves substantial improvement over the conventional text-mining baseline method. Moreover, our system discovers novel annotations for gene sets or pathways without previously known functions. Two case studies demonstrate how the system is used in discovery of new cancer-related pathways with ontological annotations.

  17. On a new concept of community: social networks, personal communities and collective intelligence

    Directory of Open Access Journals (Sweden)

    Rogério da Costa

    2006-01-01

    Full Text Available This text essentially deals with the transmutation of the concept of "community" into "social networks". This change is due largely to the boom of virtual communities in cyberspace, a fact that has generated a number of studies not only on this new way of weaving a society, but also on the dynamic structure of communication networks. At the core of this transformation, concepts such as social capital, trust and partial sympathy are called upon, to enable us to think about the new forms of association that regulate human activity in our time.

  18. Energy-efficient data collection in wireless sensor networks with time constraints

    NARCIS (Netherlands)

    Mitici, M.A.; Goseling, Jasper; de Graaf, Maurits; Boucherie, Richardus J.

    We consider the problem of retrieving a reliable estimate of an attribute from a wireless sensor network within a fixed time window and with minimum energy consumption for the sensors. The sensors are located in the plane according to some random spatial process. They perform energy harvesting and

  19. Path planning in GPS-denied environments via collective intelligence of distributed sensor networks

    Science.gov (United States)

    Jha, Devesh K.; Chattopadhyay, Pritthi; Sarkar, Soumik; Ray, Asok

    2016-05-01

    This paper proposes a framework for reactive goal-directed navigation without global positioning facilities in unknown dynamic environments. A mobile sensor network is used for localising regions of interest for path planning of an autonomous mobile robot. The underlying theory is an extension of a generalised gossip algorithm that has been recently developed in a language-measure-theoretic setting. The algorithm has been used to propagate local decisions of target detection over a mobile sensor network and thus, it generates a belief map for the detected target over the network. In this setting, an autonomous mobile robot may communicate only with a few mobile sensing nodes in its own neighbourhood and localise itself relative to the communicating nodes with bounded uncertainties. The robot makes use of the knowledge based on the belief of the mobile sensors to generate a sequence of way-points, leading to a possible goal. The estimated way-points are used by a sampling-based motion planning algorithm to generate feasible trajectories for the robot. The proposed concept has been validated by numerical simulation on a mobile sensor network test-bed and a Dubin's car-like robot.

  20. Data Collection Manual for Academic and Research Library Network Statistics and Performance Measures.

    Science.gov (United States)

    Shim, Wonsik "Jeff"; McClure, Charles R.; Fraser, Bruce T.; Bertot, John Carlo

    This manual provides a beginning approach for research libraries to better describe the use and users of their networked services. The manual also aims to increase the visibility and importance of developing such statistics and measures. Specific objectives are: to identify selected key statistics and measures that can describe use and users of…

  1. Energy-Efficient Data Collection Method for Sensor Networks by Integrating Asymmetric Communication and Wake-Up Radio

    Directory of Open Access Journals (Sweden)

    Masanari Iwata

    2018-04-01

    Full Text Available In large-scale wireless sensor networks (WSNs, nodes close to sink nodes consume energy more quickly than other nodes due to packet forwarding. A mobile sink is a good solution to this issue, although it causes two new problems to nodes: (i overhead of updating routing information; and (ii increased operating time due to aperiodic query. To solve these problems, this paper proposes an energy-efficient data collection method, Sink-based Centralized transmission Scheduling (SC-Sched, by integrating asymmetric communication and wake-up radio. Specifically, each node is equipped with a low-power wake-up receiver. The sink node determines transmission scheduling, and transmits a wake-up message using a large transmission power, directly activating a pair of nodes simultaneously which will communicate with a normal transmission power. This paper further investigates how to deal with frame loss caused by fading and how to mitigate the impact of the wake-up latency of communication modules. Simulation evaluations confirm that using multiple channels effectively reduces data collection time and SC-Sched works well with a mobile sink. Compared with the conventional duty-cycling method, SC-Sched greatly reduces total energy consumption and improves the network lifetime by 7.47 times in a WSN with 4 data collection points and 300 sensor nodes.

  2. Emergence of collective action and environmental networking in relation to radioactive waste management

    International Nuclear Information System (INIS)

    Williams, R.G.; Payne, B.A.

    1985-01-01

    This paper explores the relationship between the national environmental movement and nuclear technology in relation to a local emergent group. The historical development of nuclear technology in this conutry has followed a path leading to continued fear and mistrust of waste management by a portion of the population. At the forefront of opposition to nuclear technology are people and groups endorsing environmental values. Because of the antinuclear attitudes of environmentalists and the value orientation of appropriate technologists in the national environmental movement, it seems appropriate for local groups to call on these national groups for assistance regarding nuclear-related issues. A case study is used to illustrate how a local action group, once integrated into a national environmental network, can become an effective, legitimate participant in social change. The formation, emergence, mobilization, and networking of a local group opposed to a specific federal radioactive waste management plan is described based on organizational literature. However, inherent contradictions in defining the local versus national benefits plus inherent problems within the environmental movement could be acting to limit the effectiveness of such networks. 49 refs

  3. Eu-social science: the role of internet social networks in the collection of bee biodiversity data.

    Directory of Open Access Journals (Sweden)

    Richard Stafford

    2010-12-01

    Full Text Available Monitoring change in species diversity, community composition and phenology is vital to assess the impacts of anthropogenic activity and natural change. However, monitoring by trained scientists is time consuming and expensive.Using social networks, we assess whether it is possible to obtain accurate data on bee distribution across the UK from photographic records submitted by untrained members of the public, and if these data are in sufficient quantity for ecological studies. We used Flickr and Facebook as social networks and Flickr for the storage of photographs and associated data on date, time and location linked to them. Within six weeks, the number of pictures uploaded to the Flickr BeeID group exceeded 200. Geographic coverage was excellent; the distribution of photographs covered most of the British Isles, from the south coast of England to the Highlands of Scotland. However, only 59% of photographs were properly uploaded according to instructions, with vital information such as 'tags' or location information missing from the remainder. Nevertheless, this incorporation of information on location of photographs was much higher than general usage on Flickr (∼13%, indicating the need for dedicated projects to collect spatial ecological data. Furthermore, we found identification of bees is not possible from all photographs, especially those excluding lower abdomen detail. This suggests that giving details regarding specific anatomical features to include on photographs would be useful to maximise success.The study demonstrates the power of social network sites to generate public interest in a project and details the advantages of using a group within an existing popular social network site over a traditional (specifically-designed web-based or paper-based submission process. Some advantages include the ability to network with other individuals or groups with similar interests, and thus increasing the size of the dataset and participation

  4. On the Security of Data Collection and Transmission from Wireless Sensor Networks in the Context of Internet of Things

    OpenAIRE

    Yu, Hong; He, Jingsha; Liu, Ruohong; Ji, Dajie

    2013-01-01

    In the context of Internet of Things (IoT), multiple cooperative nodes in wireless sensor networks (WSNs) can be used to monitor an event, jointly generate a report and then send it to one or more Internet nodes for further processing. A primary security requirement in such applications is that every event data report be authenticated to intended Internet users and effectively filtered on its way to the Internet users to realize the security of data collection and transmission from the WSN. H...

  5. A Web GIS-Based Platform to Harvest Georeferenced Data from Social Networks: Examples of Data Collection Regarding Disaster Events

    Directory of Open Access Journals (Sweden)

    Cidália Costa Fonte

    2018-02-01

    Full Text Available Whenever disaster situations occur the civil protection authorities need to have fast access to data that may help to plan emergency response. To contribute to the collection and integration of all available data a platform that aims to harvest Volunteered Geographical Information (VGI from social networks and collaborative projects was created. This enables the integration of VGI with data coming from other sources, such as data collected by physical sensors in real time and made available through Applications Programming Interface (APIs, as well as, for example, official maps. The architecture of the created platform is described and its first prototype presented. Some example queries are performed and the results are analyzed.

  6. Activists’ appropriations in social networking websites: the collective action dynamics in #forasarney

    Directory of Open Access Journals (Sweden)

    BATISTA, Jandré Corrêa

    2013-01-01

    Full Text Available This paper aims to study the appropriation of Twitter (twitter.com for activists ends. To this end, we intend to present the analysis of intentionality (Thompson, 2000 of symbolic forms perceived in the appropriations social networking site (Boyd and Elisson, 2006 in case # forasarney. From the Depth Hermeneutics of Thompson (2000, the study interprets five intentions: convocacional, informational, divulgacional, feedback and conversational. The messages were classified by analyzing categorical content analysis of Bardin (2009,interpreted in accordance with its purposes.

  7. Urban Automation Networks: Current and Emerging Solutions for Sensed Data Collection and Actuation in Smart Cities.

    Science.gov (United States)

    Gomez, Carles; Paradells, Josep

    2015-09-10

    Urban Automation Networks (UANs) are being deployed worldwide in order to enable Smart City applications. Given the crucial role of UANs, as well as their diversity, it is critically important to assess their properties and trade-offs. This article introduces the requirements and challenges for UANs, characterizes the main current and emerging UAN paradigms, provides guidelines for their design and/or choice, and comparatively examines their performance in terms of a variety of parameters including coverage, power consumption, latency, standardization status and economic cost.

  8. Urban Automation Networks: Current and Emerging Solutions for Sensed Data Collection and Actuation in Smart Cities

    Directory of Open Access Journals (Sweden)

    Carles Gomez

    2015-09-01

    Full Text Available Urban Automation Networks (UANs are being deployed worldwide in order to enable Smart City applications. Given the crucial role of UANs, as well as their diversity, it is critically important to assess their properties and trade-offs. This article introduces the requirements and challenges for UANs, characterizes the main current and emerging UAN paradigms, provides guidelines for their design and/or choice, and comparatively examines their performance in terms of a variety of parameters including coverage, power consumption, latency, standardization status and economic cost.

  9. Automated collection and dissemination of ionospheric data from the digisonde network

    Directory of Open Access Journals (Sweden)

    B.W. Reinisch

    2004-01-01

    Full Text Available The growing demand for fast access to accurate ionospheric electron density profiles and ionospheric characteristics calls for efficient dissemination of data from the many ionosondes operating around the globe. The global digisonde network with over 70 stations takes advantage of the Internet to make many of these sounders remotely accessible for data transfer and control. Key elements of the digisonde system data management are the visualization and editing tool SAO Explorer, the digital ionogram database DIDBase, holding raw and derived digisonde data under an industrial-strength database management system, and the automated data request execution system ADRES.

  10. Emergence of slow collective oscillations in neural networks with spike-timing dependent plasticity

    DEFF Research Database (Denmark)

    Mikkelsen, Kaare; Imparato, Alberto; Torcini, Alessandro

    2013-01-01

    The collective dynamics of excitatory pulse coupled neurons with spike timing dependent plasticity (STDP) is studied. The introduction of STDP induces persistent irregular oscillations between strongly and weakly synchronized states, reminiscent of brain activity during slow-wave sleep. We explain...

  11. Agricultural Extension, Collective Action and Innovation Systems: Lessons on Network Brokering from Peru and Mexico

    Science.gov (United States)

    Hellin, Jon

    2012-01-01

    Purpose: New approaches to extension service delivery are needed that stimulate increased agricultural production, contribute to collective action and which also foster the emergence of agricultural innovation systems. Research in Peru and Mexico explores some of these new approaches. Design/methodology/approach: In both countries, a qualitative…

  12. Enhancing the Data Collection Rate of Tree-Based Aggregation in Wireless Sensor Networks

    NARCIS (Netherlands)

    Durmaz, O.; Krishnamachari, B.

    2008-01-01

    What is the fastest rate at which we can collect a stream of aggregated data from a set of wireless sensors organized as a tree? We explore a hierarchy of techniques using realistic simulation models to address this question. We begin by considering TDMA scheduling on a single channel, reducing the

  13. A Greedy Scanning Data Collection Strategy for Large-Scale Wireless Sensor Networks with a Mobile Sink.

    Science.gov (United States)

    Zhu, Chuan; Zhang, Sai; Han, Guangjie; Jiang, Jinfang; Rodrigues, Joel J P C

    2016-09-06

    Mobile sink is widely used for data collection in wireless sensor networks. It can avoid 'hot spot' problems but energy consumption caused by multihop transmission is still inefficient in real-time application scenarios. In this paper, a greedy scanning data collection strategy (GSDCS) is proposed, and we focus on how to reduce routing energy consumption by shortening total length of routing paths. We propose that the mobile sink adjusts its trajectory dynamically according to the changes of network, instead of predetermined trajectory or random walk. Next, the mobile sink determines which area has more source nodes, then it moves toward this area. The benefit of GSDCS is that most source nodes are no longer needed to upload sensory data for long distances. Especially in event-driven application scenarios, when event area changes, the mobile sink could arrive at the new event area where most source nodes are located currently. Hence energy can be saved. Analytical and simulation results show that compared with existing work, our GSDCS has a better performance in specific application scenarios.

  14. A Framework for Understanding Collective Leadership: The Selective Utilization of Leader and Team Expertise within Networks

    Science.gov (United States)

    2011-05-01

    characteristics (e.g., team stability, autonomy , enabling interactions) that will 22    influence collective leadership and performance. Taken...composition, the team’s autonomy , role integration, and preparation for team activities (Mumford & Hunter, 2005; Spreitzer, Cohen & Ledford, 1999; Uhl...tasks as interdependent was influenced by their belief in the value of teamwork, self-efficacy for teamwork, and collectivist feelings. Thus, the way

  15. Emergence of Slow Collective Oscillations in Neural Networks with Spike-Timing Dependent Plasticity

    Science.gov (United States)

    Mikkelsen, Kaare; Imparato, Alberto; Torcini, Alessandro

    2013-05-01

    The collective dynamics of excitatory pulse coupled neurons with spike-timing dependent plasticity is studied. The introduction of spike-timing dependent plasticity induces persistent irregular oscillations between strongly and weakly synchronized states, reminiscent of brain activity during slow-wave sleep. We explain the oscillations by a mechanism, the Sisyphus Effect, caused by a continuous feedback between the synaptic adjustments and the coherence in the neural firing. Due to this effect, the synaptic weights have oscillating equilibrium values, and this prevents the system from relaxing into a stationary macroscopic state.

  16. Tracking and disrupting dark networks: challenges of data collection and analysis

    OpenAIRE

    Roberts, Nancy C.

    2011-01-01

    The article of record as published may be found at http://dx.doi.org/10.1007/s10796-010-9271-z The attack on September 11, 2001 set off numerous efforts to counter terrorism and insurgencies. Central to these efforts has been the drive to improve data collection and analysis. Section 1 summarizes some of the more notable improvements among U.S. government agencies as they strive to develop their capabilities. Although progress has been made, daunting challenges remain. Section 2 reviews th...

  17. Environmental assessment of wood industrial and collective (with heat network) heating. Synthetic report

    International Nuclear Information System (INIS)

    2005-12-01

    This report proposes a synthesis of the results of an environmental assessment of wood industrial and collective heating. This study is based on a life cycle analysis which quantifies the impacts on the environment of all the related activities: fuel extraction, retailing, final use, and so on. Environmental impacts are assessed by means of different indicators: energetic assessment, greenhouse effect assessment, air pollution (acidification), water pollution (eutrophication), toxic material emissions in air and into the soils. Wood is compared to other heating sources (gas, fuel, electricity). Ways to improve this environmental assessment are discussed with respect to wood supply, boiler auxiliary equipment, boiler and combustion

  18. Randomness in the network inhibits cooperation based on the bounded rational collective altruistic decision

    International Nuclear Information System (INIS)

    Ohdaira, Tetsushi

    2014-01-01

    Previous studies discussing cooperation employ the best decision that every player knows all information regarding the payoff matrix and selects the strategy of the highest payoff. Therefore, they do not discuss cooperation based on the altruistic decision with limited information (bounded rational altruistic decision). In addition, they do not cover the case where every player can submit his/her strategy several times in a match of the game. This paper is based on Ohdaira's reconsideration of the bounded rational altruistic decision, and also employs the framework of the prisoner's dilemma game (PDG) with sequential strategy. The distinction between this study and the Ohdaira's reconsideration is that the former covers the model of multiple groups, but the latter deals with the model of only two groups. Ohdaira's reconsideration shows that the bounded rational altruistic decision facilitates much more cooperation in the PDG with sequential strategy than Ohdaira and Terano's bounded rational second-best decision does. However, the detail of cooperation of multiple groups based on the bounded rational altruistic decision has not been resolved yet. This study, therefore, shows how randomness in the network composed of multiple groups affects the increase of the average frequency of mutual cooperation (cooperation between groups) based on the bounded rational altruistic decision of multiple groups. We also discuss the results of the model in comparison with related studies which employ the best decision. (paper)

  19. Randomness in the network inhibits cooperation based on the bounded rational collective altruistic decision

    Science.gov (United States)

    Ohdaira, Tetsushi

    2014-07-01

    Previous studies discussing cooperation employ the best decision that every player knows all information regarding the payoff matrix and selects the strategy of the highest payoff. Therefore, they do not discuss cooperation based on the altruistic decision with limited information (bounded rational altruistic decision). In addition, they do not cover the case where every player can submit his/her strategy several times in a match of the game. This paper is based on Ohdaira's reconsideration of the bounded rational altruistic decision, and also employs the framework of the prisoner's dilemma game (PDG) with sequential strategy. The distinction between this study and the Ohdaira's reconsideration is that the former covers the model of multiple groups, but the latter deals with the model of only two groups. Ohdaira's reconsideration shows that the bounded rational altruistic decision facilitates much more cooperation in the PDG with sequential strategy than Ohdaira and Terano's bounded rational second-best decision does. However, the detail of cooperation of multiple groups based on the bounded rational altruistic decision has not been resolved yet. This study, therefore, shows how randomness in the network composed of multiple groups affects the increase of the average frequency of mutual cooperation (cooperation between groups) based on the bounded rational altruistic decision of multiple groups. We also discuss the results of the model in comparison with related studies which employ the best decision.

  20. Mapping quorum sensing onto neural networks to understand collective decision making in heterogeneous microbial communities

    Science.gov (United States)

    Yusufaly, Tahir I.; Boedicker, James Q.

    2017-08-01

    Microbial communities frequently communicate via quorum sensing (QS), where cells produce, secrete, and respond to a threshold level of an autoinducer (AI) molecule, thereby modulating gene expression. However, the biology of QS remains incompletely understood in heterogeneous communities, where variant bacterial strains possess distinct QS systems that produce chemically unique AIs. AI molecules bind to ‘cognate’ receptors, but also to ‘non-cognate’ receptors found in other strains, resulting in inter-strain crosstalk. Understanding these interactions is a prerequisite for deciphering the consequences of crosstalk in real ecosystems, where multiple AIs are regularly present in the same environment. As a step towards this goal, we map crosstalk in a heterogeneous community of variant QS strains onto an artificial neural network model. This formulation allows us to systematically analyze how crosstalk regulates the community’s capacity for flexible decision making, as quantified by the Boltzmann entropy of all QS gene expression states of the system. In a mean-field limit of complete cross-inhibition between variant strains, the model is exactly solvable, allowing for an analytical formula for the number of variants that maximize capacity as a function of signal kinetics and activation parameters. An analysis of previous experimental results on the Staphylococcus aureus two-component Agr system indicates that the observed combination of variant numbers, gene expression rates and threshold concentrations lies near this critical regime of parameter space where capacity peaks. The results are suggestive of a potential evolutionary driving force for diversification in certain QS systems.

  1. Intelligent Management System of Power Network Information Collection Under Big Data Storage

    Directory of Open Access Journals (Sweden)

    Qin Yingying

    2017-01-01

    Full Text Available With the development of economy and society, big data storage in enterprise management has become a problem that can’t be ignored. How to manage and optimize the allocation of tasks better is an important factor in the sustainable development of an enterprise. Now the enterprise information intelligent management has become a hot spot of management mode and concept in the information age. It presents information to the business managers in a more efficient, lower cost, and global form. The system uses the SG-UAP development tools, which is based on Eclipse development environment, and suits for Windows operating system, with Oracle as database development platform, Tomcat network information service for application server. The system uses SOA service-oriented architecture, provides RESTful style service, and HTTP(S as the communication protocol, and JSON as the data format. The system is divided into two parts, the front-end and the backs-end, achieved functions like user login, registration, password retrieving, enterprise internal personnel information management and internal data display and other functions.

  2. Interactive analysis of geographically distributed population imaging data collections over light-path data networks

    Science.gov (United States)

    van Lew, Baldur; Botha, Charl P.; Milles, Julien R.; Vrooman, Henri A.; van de Giessen, Martijn; Lelieveldt, Boudewijn P. F.

    2015-03-01

    The cohort size required in epidemiological imaging genetics studies often mandates the pooling of data from multiple hospitals. Patient data, however, is subject to strict privacy protection regimes, and physical data storage may be legally restricted to a hospital network. To enable biomarker discovery, fast data access and interactive data exploration must be combined with high-performance computing resources, while respecting privacy regulations. We present a system using fast and inherently secure light-paths to access distributed data, thereby obviating the need for a central data repository. A secure private cloud computing framework facilitates interactive, computationally intensive exploration of this geographically distributed, privacy sensitive data. As a proof of concept, MRI brain imaging data hosted at two remote sites were processed in response to a user command at a third site. The system was able to automatically start virtual machines, run a selected processing pipeline and write results to a user accessible database, while keeping data locally stored in the hospitals. Individual tasks took approximately 50% longer compared to a locally hosted blade server but the cloud infrastructure reduced the total elapsed time by a factor of 40 using 70 virtual machines in the cloud. We demonstrated that the combination light-path and private cloud is a viable means of building an analysis infrastructure for secure data analysis. The system requires further work in the areas of error handling, load balancing and secure support of multiple users.

  3. Reliable communication stack for flexible probe vehicle data collection in vehicular ad hoc networks

    DEFF Research Database (Denmark)

    Paulin, Thomas

    Traffic congestions caused by high vehicular densities are an ever increasing problem for both personal and professional transportation, resulting in significant losses each year. While expanding the road infrastructure often offers a short term solution, more intelligent approaches are necessary...... the communication resource a single access point can provide for delay tolerant applications. 2) We improve the information exchange between road-side units and vehicles by identifying communication characteristics of the road-side unit and use them to determine the optimal location at which the information...... exchange should occur. 3) We extend the coverage range of the road-side units through vehicle to vehicle communication by modifying an existing routing algorithm, improving both delivery rate and communication overhead. Applying the proposed methodologies on the collection of probe data provides...

  4. Comparison of sputum collection methods for tuberculosis diagnosis: a systematic review and pairwise and network meta-analysis.

    Science.gov (United States)

    Datta, Sumona; Shah, Lena; Gilman, Robert H; Evans, Carlton A

    2017-08-01

    The performance of laboratory tests to diagnose pulmonary tuberculosis is dependent on the quality of the sputum sample tested. The relative merits of sputum collection methods to improve tuberculosis diagnosis are poorly characterised. We therefore aimed to investigate the effects of sputum collection methods on tuberculosis diagnosis. We did a systematic review and meta-analysis to investigate whether non-invasive sputum collection methods in people aged at least 12 years improve the diagnostic performance of laboratory testing for pulmonary tuberculosis. We searched PubMed, Google Scholar, ProQuest, Web of Science, CINAHL, and Embase up to April 14, 2017, to identify relevant experimental, case-control, or cohort studies. We analysed data by pairwise meta-analyses with a random-effects model and by network meta-analysis. All diagnostic performance data were calculated at the sputum-sample level, except where authors only reported data at the individual patient-level. Heterogeneity was assessed, with potential causes identified by logistic meta-regression. We identified 23 eligible studies published between 1959 and 2017, involving 8967 participants who provided 19 252 sputum samples. Brief, on-demand spot sputum collection was the main reference standard. Pooled sputum collection increased tuberculosis diagnosis by microscopy (odds ratio [OR] 1·6, 95% CI 1·3-1·9, pmeta-analysis confirmed these findings, and revealed that both pooled and instructed spot sputum collections were similarly effective techniques for increasing the diagnostic performance of microscopy. Tuberculosis diagnoses were substantially increased by either pooled collection or by providing instruction on how to produce a sputum sample taken at any time of the day. Both interventions had a similar effect to that reported for the introduction of new, expensive laboratory tests, and therefore warrant further exploration in the drive to end the global tuberculosis epidemic. Wellcome Trust

  5. Evaluating the feasibility of using online software to collect patient information in a chiropractic practice-based research network.

    Science.gov (United States)

    Kania-Richmond, Ania; Weeks, Laura; Scholten, Jeffrey; Reney, Mikaël

    2016-03-01

    Practice based research networks (PBRNs) are increasingly used as a tool for evidence based practice. We developed and tested the feasibility of using software to enable online collection of patient data within a chiropractic PBRN to support clinical decision making and research in participating clinics. To assess the feasibility of using online software to collect quality patient information. The study consisted of two phases: 1) Assessment of the quality of information provided, using a standardized form; and 2) Exploration of patients' perspectives and experiences regarding online information provision through semi-structured interviews. Data analysis was descriptive. Forty-five new patients were recruited. Thirty-six completed online forms, which were submitted by an appropriate person 100% of the time, with an error rate of less than 1%, and submitted in a timely manner 83% of the time. Twenty-one participants were interviewed. Overall, online forms were preferred given perceived security, ease of use, and enabling provision of more accurate information. Use of online software is feasible, provides high quality information, and is preferred by most participants. A pen-and-paper format should be available for patients with this preference and in case of technical difficulties.

  6. FCJ-157 Still ‘Searching for Safety Online’: collective strategies and discursive resistance to trolling and harassment in a feminist network

    Directory of Open Access Journals (Sweden)

    Frances Shaw

    2013-12-01

    Full Text Available This paper examines the discursive responses that participants in a network of feminist blogs developed to handle trolling in their community. Internet communities develop strategies to deal with trolls in their networks. In particular, participants provide instructions and guidance to support each other to deal with trolls and harassment, and engage in intra-community discussion about the significance or insignificance of trolls. My paper explores the practices that feminist bloggers engage in to resist silencing practices, and the ways in which the silencing of female voices does not work in these contexts. I argue that trolling and discursive responses to trolls are collectively developed and enforced. Using a case study from my research into Australian feminist blogging networks, I argue that these networks have developed particular collective responses to trolls.

  7. Networking

    OpenAIRE

    Rauno Lindholm, Daniel; Boisen Devantier, Lykke; Nyborg, Karoline Lykke; Høgsbro, Andreas; Fries, de; Skovlund, Louise

    2016-01-01

    The purpose of this project was to examine what influencing factor that has had an impact on the presumed increasement of the use of networking among academics on the labour market and how it is expressed. On the basis of the influence from globalization on the labour market it can be concluded that the globalization has transformed the labour market into a market based on the organization of networks. In this new organization there is a greater emphasis on employees having social qualificati...

  8. Artificial Neural Networks-Based Software for Measuring Heat Collection Rate and Heat Loss Coefficient of Water-in-Glass Evacuated Tube Solar Water Heaters

    Science.gov (United States)

    Liu, Zhijian; Liu, Kejun; Li, Hao; Zhang, Xinyu; Jin, Guangya; Cheng, Kewei

    2015-01-01

    Measurements of heat collection rate and heat loss coefficient are crucial for the evaluation of in service water-in-glass evacuated tube solar water heaters. However, conventional measurement requires expensive detection devices and undergoes a series of complicated procedures. To simplify the measurement and reduce the cost, software based on artificial neural networks for measuring heat collection rate and heat loss coefficient of water-in-glass evacuated tube solar water heaters was developed. Using multilayer feed-forward neural networks with back-propagation algorithm, we developed and tested our program on the basis of 915measuredsamples of water-in-glass evacuated tube solar water heaters. This artificial neural networks-based software program automatically obtained accurate heat collection rateand heat loss coefficient using simply "portable test instruments" acquired parameters, including tube length, number of tubes, tube center distance, heat water mass in tank, collector area, angle between tubes and ground and final temperature. Our results show that this software (on both personal computer and Android platforms) is efficient and convenient to predict the heat collection rate and heat loss coefficient due to it slow root mean square errors in prediction. The software now can be downloaded from http://t.cn/RLPKF08. PMID:26624613

  9. Artificial Neural Networks-Based Software for Measuring Heat Collection Rate and Heat Loss Coefficient of Water-in-Glass Evacuated Tube Solar Water Heaters.

    Science.gov (United States)

    Liu, Zhijian; Liu, Kejun; Li, Hao; Zhang, Xinyu; Jin, Guangya; Cheng, Kewei

    2015-01-01

    Measurements of heat collection rate and heat loss coefficient are crucial for the evaluation of in service water-in-glass evacuated tube solar water heaters. However, conventional measurement requires expensive detection devices and undergoes a series of complicated procedures. To simplify the measurement and reduce the cost, software based on artificial neural networks for measuring heat collection rate and heat loss coefficient of water-in-glass evacuated tube solar water heaters was developed. Using multilayer feed-forward neural networks with back-propagation algorithm, we developed and tested our program on the basis of 915 measured samples of water-in-glass evacuated tube solar water heaters. This artificial neural networks-based software program automatically obtained accurate heat collection rate and heat loss coefficient using simply "portable test instruments" acquired parameters, including tube length, number of tubes, tube center distance, heat water mass in tank, collector area, angle between tubes and ground and final temperature. Our results show that this software (on both personal computer and Android platforms) is efficient and convenient to predict the heat collection rate and heat loss coefficient due to it slow root mean square errors in prediction. The software now can be downloaded from http://t.cn/RLPKF08.

  10. Collective arrangements and social networks: Coping strategies for the poor households in the Great Ruaha Catchment in Tanzania

    Science.gov (United States)

    Kadigi, Reuben M. J.; Mdoe, N. S. Y.; Ashimogo, G. C.

    Access to water and land resources underpins the socio-economic fabric of many societies in the Southern Africa region, which is characterized broadly as underdeveloped with widespread food insecurity, exacerbated by persistent droughts, erratic rainfalls and increasing human populations. The availability of land and water resources is increasingly diminishing and becoming a stumbling block to the development of the agrarian societies in the region. The poor households have in turn adopted new livelihood coping mechanisms but little research has been done to assess the effectiveness of these ‘instruments’. Consequently, the concepts of sustainable water resources management and agricultural development have remained elusive and poorly understood by policy makers as well as by water resources planners and managers. Recognizing this, a study was conducted between 2002 and 2005 under the RIPARWIN (Raising Irrigation Productivity and Releasing Water for Intersectoral Needs) project to assess the spatial dynamics of livelihood capital, vulnerability and coping strategies for the poor agrarian households in the Upper Great Ruaha River Catchment (GRRC) in Tanzania. The results of analysis showed an array of livelihood platforms and institutional contexts that act to shape the existing livelihood typologies in the GRRC. In addition, the results showed a gradual increase in household vulnerability from upstream to downstream, particularly in terms of access to physical and natural assets. Vulnerability was found to be directly associated with the number of dependants. The female-headed households were relatively more likely to be vulnerable than the male-headed households (cf. probabilities of 27% and 21%, respectively). The value of collective arrangements and drawing on social networks crosscut all social strata and ranked as the most common livelihood strategy. This suggests that the scope for reducing vulnerability among the poor households in the GRRC critically

  11. Surface-water data and statistics from U.S. Geological Survey data-collection networks in New Jersey on the World Wide Web

    Science.gov (United States)

    Reiser, Robert G.; Watson, Kara M.; Chang, Ming; Nieswand, Steven P.

    2002-01-01

    The U.S. Geological Survey (USGS), in cooperation with other Federal, State, and local agencies, operates and maintains a variety of surface-water data-collection networks throughout the State of New Jersey. The networks include streamflow-gaging stations, low-flow sites, crest-stage gages, tide gages, tidal creststage gages, and water-quality sampling sites. Both real-time and historical surface-water data for many of the sites in these networks are available at the USGS, New Jersey District, web site (http://nj.usgs.gov/), and water-quality data are available at the USGS National Water Information System (NWIS) web site (http://waterdata.usgs.gov/nwis/). These data are an important source of information for water managers, engineers, environmentalists, and private citizens.

  12. Molecular surveillance of norovirus, 2005-16: an epidemiological analysis of data collected from the NoroNet network.

    NARCIS (Netherlands)

    van Beek, Janko; de Graaf, Miranda; Al-Hello, Haider; Allen, David J; Ambert-Balay, Katia; Botteldoorn, Nadine; Brytting, Mia; Buesa, Javier; Cabrerizo, Maria; Chan, Martin; Cloak, Fiona; Di Bartolo, Ilaria; Guix, Susana; Hewitt, Joanne; Iritani, Nobuhiro; Jin, Miao; Johne, Reimar; Lederer, Ingeborg; Mans, Janet; Martella, Vito; Maunula, Leena; McAllister, Georgina; Niendorf, Sandra; Niesters, Hubert G; Podkolzin, Alexander T; Poljsak-Prijatelj, Mateja; Rasmussen, Lasse Dam; Reuter, Gábor; Tuite, Gráinne; Kroneman, Annelies; Vennema, Harry; Koopmans, Marion P G

    2018-01-01

    The development of a vaccine for norovirus requires a detailed understanding of global genetic diversity of noroviruses. We analysed their epidemiology and diversity using surveillance data from the NoroNet network.

  13. Towards Internet of Things (IOTS):Integration of Wireless Sensor Network to Cloud Services for Data Collection and Sharing

    OpenAIRE

    Piyare, Rajeev; Lee, Seong Ro

    2013-01-01

    Cloud computing provides great benefits for applications hosted on the Web that also have special computational and storage requirements. This paper proposes an extensible and flexible architecture for integrating Wireless Sensor Networks with the Cloud. We have used REST based Web services as an interoperable application layer that can be directly integrated into other application domains for remote monitoring such as e-health care services, smart homes, or even vehicular area networks (VAN)...

  14. The Strip Clustering Scheme for data collection in large-scale Wireless Sensing Network of the road

    Directory of Open Access Journals (Sweden)

    Zhoujing Ye

    2018-03-01

    Full Text Available For intelligent traffic and road structural health monitoring, Wireless Sensing Network has been applied widely in transportation, and large quantity of sensor nodes have been embedded in roadways. Now the service lives of sensors are limited mainly because of their battery power storage. So the life cycle of the whole network can be extended if the service life of each sensor in the network is prolonged. In this paper, the Strip Clustering Scheme (SCS is proposed to replace the Conventional Scheme (CS. This method includes region division, cluster head node selection, link construction, data fusion and transmission. Adopting SCS can reduce a lot of redundant data and the total energy consumption of the network by data fusion. In addition, adopting SCS can also extend the monitoring area without increasing the communication range of the Access Point (AP, and facilitate further expansion of the network as a result. Based on the numerically simulated results, CS method can be used for the WSN within 75 m, and SCS method is more suitable when the monitoring range is larger than 75 m. To achieve the optimal network costs and the network life cycle by using SCS, the range of d (the longitudinal spacing of adjacent nodes, is suggested as 10–12.5 m and the energy of cluster head nodes is 60% higher than the energy of non-head nodes with fixed w (the transverse distance of adjacent nodes. And the extra energy of head nodes can be obtained by adding the number of battery within the head nodes or using renewable energy technologies. Keywords: WSN, Road, Energy consumption, Conventional Scheme, Strip Clustering Scheme

  15. Modeling individual and collective opinion in online social networks: drivers of choice behavior and effects of marketing interventions

    NARCIS (Netherlands)

    Koster, S.E.; Langley, D.J.

    2013-01-01

    We investigate factors influencing choice behavior in online social networks. We use twitter data from a Dutch television talent show. In study one, we implement a nested conditional logit model with latent classes. We find heterogeneous effects. For two latent classes, cognitive factors most

  16. Molecular surveillance of norovirus, 2005-16 : an epidemiological analysis of data collected from the NoroNet network

    NARCIS (Netherlands)

    van Beek, Janko; de Graaf, Miranda; Al-Hello, Haider; Allen, David J; Ambert-Balay, Katia; Botteldoorn, Nadine; Brytting, Mia; Buesa, Javier; Cabrerizo, Maria; Chan, Martin; Cloak, Fiona; Di Bartolo, Ilaria; Guix, Susana; Hewitt, Joanne; Iritani, Nobuhiro; Jin, Miao; Johne, Reimar; Lederer, Ingeborg; Mans, Janet; Martella, Vito; Maunula, Leena; McAllister, Georgina; Niendorf, Sandra; Niesters, Hubert G; Podkolzin, Alexander T; Poljsak-Prijatelj, Mateja; Rasmussen, Lasse Dam; Reuter, Gábor; Tuite, Gráinne; Kroneman, Annelies; Vennema, Harry; Koopmans, Marion P G

    BACKGROUND: The development of a vaccine for norovirus requires a detailed understanding of global genetic diversity of noroviruses. We analysed their epidemiology and diversity using surveillance data from the NoroNet network. METHODS: We included genetic sequences of norovirus specimens obtained

  17. The use of cell phone network data in traffic data collection and long-haul truckshed (geographic extent) tracking.

    Science.gov (United States)

    2012-12-01

    This study analyzed the potential of cell phone positioning techniques in freight truck data collection and long-haul : truckshed (geographic extent) tracking. Freight truck identification and tracking algorithms were developed by means of : cell pho...

  18. Distributed Joint Cluster Formation and Resource Allocation Scheme for Cooperative Data Collection in Virtual MIMO-Based M2M Networks

    Directory of Open Access Journals (Sweden)

    Xi Luan

    2015-01-01

    Full Text Available An efficient data collection scheme plays an important role for the real-time intelligent monitoring in many machine-to-machine (M2M networks. In this paper, a distributed joint cluster formation and resource allocation scheme for data collection in cluster-based M2M networks is proposed. Specifically, in order to utilize the advantages of cooperation, we first propose a hierarchical transmission model which contains two communication phases. In the first phase, the intracluster information sharing is carried out by all the nodes within the same cluster. Then these nodes transmit the total information to the BS cooperatively with virtual-MIMO (VMIMO protocol in the second phase. To grasp the properties and advantages of this cooperative transmission strategy, the theoretical analysis results are provided. The key issue in this system is to form the clusters and allocate resources efficiently. Since the optimization problem on this issue is an NP-hard problem, a feasible joint scheme for the cluster formation and resource allocation is proposed in this paper, which is carried out via coalition formation game with a distributed algorithm. This scheme can reduce the complexity while keeping an attractive performance. Simulation results show the properties of the proposed scheme and its advantages when comparing with the noncooperative scheme for the data collection in a practical scenario.

  19. An Interactive, Mobile-Based Tool for Personal Social Network Data Collection and Visualization Among a Geographically Isolated and Socioeconomically Disadvantaged Population: Early-Stage Feasibility Study With Qualitative User Feedback.

    Science.gov (United States)

    Eddens, Katherine S; Fagan, Jesse M; Collins, Tom

    2017-06-22

    Personal social networks have a profound impact on our health, yet collecting personal network data for use in health communication, behavior change, or translation and dissemination interventions has proved challenging. Recent advances in social network data collection software have reduced the burden of network studies on researchers and respondents alike, yet little testing has occurred to discover whether these methods are: (1) acceptable to a variety of target populations, including those who may have limited experience with technology or limited literacy; and (2) practical in the field, specifically in areas that are geographically and technologically disconnected, such as rural Appalachian Kentucky. We explored the early-stage feasibility (Acceptability, Demand, Implementation, and Practicality) of using innovative, interactive, tablet-based network data collection and visualization software (OpenEddi) in field collection of personal network data in Appalachian Kentucky. A total of 168 rural Appalachian women who had previously participated in a study on the use of a self-collected vaginal swab (SCVS) for human papillomavirus testing were recruited by community-based nurse interviewers between September 2013 and August 2014. Participants completed egocentric network surveys via OpenEddi, which captured social and communication network influences on participation in, and recruitment to, the SCVS study. After study completion, we conducted a qualitative group interview with four nurse interviewers and two participants in the network study. Using this qualitative data, and quantitative data from the network study, we applied guidelines from Bowen et al to assess feasibility in four areas of early-stage development of OpenEddi: Acceptability, Demand, Implementation, and Practicality. Basic descriptive network statistics (size, edges, density) were analyzed using RStudio. OpenEddi was perceived as fun, novel, and superior to other data collection methods or tools

  20. Physical profile data collected in the Equatorial Pacific during cruises to service the TAO/TRITON array, a network of deep ocean moored buoys, February 23 - December 16, 2005 (NODC Accession 0002644)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — During 2005, CTD data were collected in the equatorial Pacific Ocean during cruises to service the TAO/TRITON array, a network of deep ocean moored buoys to support...

  1. A Latency and Coverage Optimized Data Collection Scheme for Smart Cities Based on Vehicular Ad-hoc Networks.

    Science.gov (United States)

    Xu, Yixuan; Chen, Xi; Liu, Anfeng; Hu, Chunhua

    2017-04-18

    Using mobile vehicles as "data mules" to collect data generated by a huge number of sensing devices that are widely spread across smart city is considered to be an economical and effective way of obtaining data about smart cities. However, currently most research focuses on the feasibility of the proposed methods instead of their final performance. In this paper, a latency and coverage optimized data collection (LCODC) scheme is proposed to collect data on smart cities through opportunistic routing. Compared with other schemes, the efficiency of data collection is improved since the data flow in LCODC scheme consists of not only vehicle to device transmission (V2D), but also vehicle to vehicle transmission (V2V). Besides, through data mining on patterns hidden in the smart city, waste and redundancy in the utilization of public resources are mitigated, leading to the easy implementation of our scheme. In detail, no extra supporting device is needed in the LCODC scheme to facilitate data transmission. A large-scale and real-world dataset on Beijing is used to evaluate the LCODC scheme. Results indicate that with very limited costs, the LCODC scheme enables the average latency to decrease from several hours to around 12 min with respect to schemes where V2V transmission is disabled while the coverage rate is able to reach over 30%.

  2. A Latency and Coverage Optimized Data Collection Scheme for Smart Cities Based on Vehicular Ad-hoc Networks

    Directory of Open Access Journals (Sweden)

    Yixuan Xu

    2017-04-01

    Full Text Available Using mobile vehicles as “data mules” to collect data generated by a huge number of sensing devices that are widely spread across smart city is considered to be an economical and effective way of obtaining data about smart cities. However, currently most research focuses on the feasibility of the proposed methods instead of their final performance. In this paper, a latency and coverage optimized data collection (LCODC scheme is proposed to collect data on smart cities through opportunistic routing. Compared with other schemes, the efficiency of data collection is improved since the data flow in LCODC scheme consists of not only vehicle to device transmission (V2D, but also vehicle to vehicle transmission (V2V. Besides, through data mining on patterns hidden in the smart city, waste and redundancy in the utilization of public resources are mitigated, leading to the easy implementation of our scheme. In detail, no extra supporting device is needed in the LCODC scheme to facilitate data transmission. A large-scale and real-world dataset on Beijing is used to evaluate the LCODC scheme. Results indicate that with very limited costs, the LCODC scheme enables the average latency to decrease from several hours to around 12 min with respect to schemes where V2V transmission is disabled while the coverage rate is able to reach over 30%.

  3. A Latency and Coverage Optimized Data Collection Scheme for Smart Cities Based on Vehicular Ad-Hoc Networks

    Science.gov (United States)

    Xu, Yixuan; Chen, Xi; Liu, Anfeng; Hu, Chunhua

    2017-01-01

    Using mobile vehicles as “data mules” to collect data generated by a huge number of sensing devices that are widely spread across smart city is considered to be an economical and effective way of obtaining data about smart cities. However, currently most research focuses on the feasibility of the proposed methods instead of their final performance. In this paper, a latency and coverage optimized data collection (LCODC) scheme is proposed to collect data on smart cities through opportunistic routing. Compared with other schemes, the efficiency of data collection is improved since the data flow in LCODC scheme consists of not only vehicle to device transmission (V2D), but also vehicle to vehicle transmission (V2V). Besides, through data mining on patterns hidden in the smart city, waste and redundancy in the utilization of public resources are mitigated, leading to the easy implementation of our scheme. In detail, no extra supporting device is needed in the LCODC scheme to facilitate data transmission. A large-scale and real-world dataset on Beijing is used to evaluate the LCODC scheme. Results indicate that with very limited costs, the LCODC scheme enables the average latency to decrease from several hours to around 12 min with respect to schemes where V2V transmission is disabled while the coverage rate is able to reach over 30%. PMID:28420218

  4. Putting Citizen-Collected Observations to Work -- The Community Collaborative Rain, Hail and Snow Network (CoCoRaHS)

    Science.gov (United States)

    Doesken, N.

    2015-12-01

    When CoCoRaHS was born (1998), climate-relevant information was far from our minds. We were simply enlisting volunteers to help capture, display and communicate the nature of small scale variability within northern Colorado storms. Climate change was talked about then, but not with the sense of concern and urgency as today. Now, many years later, the simple back-yard precipitation measurements being taken by thousands of volunteers across much of North America are creating valuable and easily-accessible data and information serving many and varied purposes from federal and state climate monitoring to drought and extreme storm analysis and research. Many volunteers have been with the project now for a decade or longer and have contributed literally thousands of individual observations and reports. Long-time participants along with recent recruits of all ages are seeing first-hand how day by day observations of weather conditions combine - over time and space -- to define and describe key elements of our climate and its variations. The fact that the data from volunteers are frequently used and applied by scientists and decision makers is one of the key factors in retaining long-term volunteers. Examples will be presented of volunteer precipitation data being used both independently and in combination with data from federal monitoring systems. Challenges of maintaining a large volunteer network will be discussed along with some plans and opportunities for the future.

  5. Interconnected networks

    CERN Document Server

    2016-01-01

    This volume provides an introduction to and overview of the emerging field of interconnected networks which include multi layer or multiplex networks, as well as networks of networks. Such networks present structural and dynamical features quite different from those observed in isolated networks. The presence of links between different networks or layers of a network typically alters the way such interconnected networks behave – understanding the role of interconnecting links is therefore a crucial step towards a more accurate description of real-world systems. While examples of such dissimilar properties are becoming more abundant – for example regarding diffusion, robustness and competition – the root of such differences remains to be elucidated. Each chapter in this topical collection is self-contained and can be read on its own, thus making it also suitable as reference for experienced researchers wishing to focus on a particular topic.

  6. Coupling Flux Towers and Networks with Proximal and Remote Sensing Data: New Tools to Collect and Share Time-Synchronized Hourly Fluxes

    Science.gov (United States)

    Burba, George; Avenson, Tom; Burkart, Andreas; Gamon, John; Guan, Kaiyu; Julitta, Tommaso; Pastorello, Gilberto; Sakowska, Karolina

    2017-04-01

    Multiple hundreds of flux towers are presently operational as standalone projects and as parts of larger networks. However, the vast majority of these towers do not allow straight-forward coupling with satellite data, and even fewer have optical sensors for validation of satellite products and upscaling from field to regional levels. In 2016, new tools to collect, process, and share time-synchronized flux data from multiple towers were developed and deployed globally. Originally designed to automate site and data management, these new tools can also be effective in coupling tower data with satellite data due to the following present capabilities: Fully automated FluxSuite system combines hardware, software and web-services, and does not require an expert to run it It can be incorporated into a new flux station or added to a present station, using weatherized remotely-accessible microcomputer, SmartFlux2 It utilizes EddyPro software to calculate fully-processed fluxes and footprints in near-realtime, alongside radiation, optical, weather and soil data All site data are merged into a single quality-controlled file timed using PTP time protocol Data from optical sensors can be integrated into this complete dataset via compatible dataloggers Multiple stations can be linked into time-synchronized network with automated reports and email alerts visible to PIs in real-time Remote sensing researchers without stations can form "virtual networks" of stations by collaborating with tower PIs from different physical networks The present system can then be utilized to couple ground data with satellite data via the following proposed concept: GPS-driven PTP protocol will synchronize instrumentation within the station, different stations with each other, and all of these to satellite data to precisely align optical and flux data in time Footprint size and coordinates computed and stored with flux data will help correctly align footprints and satellite motion to precisely align

  7. Collection Directions: The Evolution of Library Collections and Collecting

    Science.gov (United States)

    Dempsey, Lorcan; Malpas, Constance; Lavoie, Brian

    2014-01-01

    This article takes a broad view of the evolution of collecting behaviors in a network environment and suggests some future directions based on various simple models. The authors look at the changing dynamics of print collections, at the greater engagement with research and learning behaviors, and at trends in scholarly communication. The goal is…

  8. Design and maintenance of a network for collecting high-resolution suspended-sediment data at remote locations on rivers, with examples from the Colorado River

    Science.gov (United States)

    Griffiths, Ronald E.; Topping, David J.; Andrews, Timothy; Bennett, Glenn E.; Sabol, Thomas A.; Melis, Theodore S.

    2012-01-01

    instruments have been constructed and verified by using either equal-discharge-increment (EDI) or equal-width-increment (EWI) measurements of the velocity-weighted suspended-sediment concentration and grain-size distribution. The suspended-silt-and-clay concentration parts of these calibration relations have also included information from EDI- or EWI-calibrated samples collected by automatic pump samplers. Three of the monitoring stations are equipped with two-way satellite broadband telemetry systems that operate once a day to remotely monitor and program the instruments and download data. Data from these stations are typically downloaded twice per month; data from stations without satellite-telemetry systems are downloaded during site visits, which occur every 2 months or semiannually, depending on the remoteness of the site. Upon downloading and processing, suspended-silt-and-clay concentration, suspended-sand concentration, and suspended-sand median grain size are posted on the World Wide Web. Satellite telemetry in combination with the high-resolution sediment surrogate measurements can generate near-real-time suspended-sediment-concentration and grain-size data (limited only by the time required to download the instruments and process the data). The approach for measuring suspended-sediment concentration and grain size using this monitoring network is more practical, and can be done at a much lower cost and with higher temporal resolution, than any other method.

  9. The Surge, Wave, and Tide Hydrodynamics (SWaTH) network of the U.S. Geological Survey—Past and future implementation of storm-response monitoring, data collection, and data delivery

    Science.gov (United States)

    Verdi, Richard J.; Lotspeich, R. Russell; Robbins, Jeanne C.; Busciolano, Ronald J.; Mullaney, John R.; Massey, Andrew J.; Banks, William S.; Roland, Mark A.; Jenter, Harry L.; Peppler, Marie C.; Suro, Thomas P.; Schubert, Christopher E.; Nardi, Mark R.

    2017-06-20

    After Hurricane Sandy made landfall along the northeastern Atlantic coast of the United States on October 29, 2012, the U.S. Geological Survey (USGS) carried out scientific investigations to assist with protecting coastal communities and resources from future flooding. The work included development and implementation of the Surge, Wave, and Tide Hydrodynamics (SWaTH) network consisting of more than 900 monitoring stations. The SWaTH network was designed to greatly improve the collection and timely dissemination of information related to storm surge and coastal flooding. The network provides a significant enhancement to USGS data-collection capabilities in the region impacted by Hurricane Sandy and represents a new strategy for observing and monitoring coastal storms, which should result in improved understanding, prediction, and warning of storm-surge impacts and lead to more resilient coastal communities.As innovative as it is, SWaTH evolved from previous USGS efforts to collect storm-surge data needed by others to improve storm-surge modeling, warning, and mitigation. This report discusses the development and implementation of the SWaTH network, and some of the regional stories associated with the landfall of Hurricane Sandy, as well as some previous events that informed the SWaTH development effort. Additional discussions on the mechanics of inundation and how the USGS is working with partners to help protect coastal communities from future storm impacts are also included.

  10. Nutrient and pesticide contamination bias estimated from field blanks collected at surface-water sites in U.S. Geological Survey Water-Quality Networks, 2002–12

    Science.gov (United States)

    Medalie, Laura; Martin, Jeffrey D.

    2017-08-14

    Potential contamination bias was estimated for 8 nutrient analytes and 40 pesticides in stream water collected by the U.S. Geological Survey at 147 stream sites from across the United States, and representing a variety of hydrologic conditions and site types, for water years 2002–12. This study updates previous U.S. Geological Survey evaluations of potential contamination bias for nutrients and pesticides. Contamination is potentially introduced to water samples by exposure to airborne gases and particulates, from inadequate cleaning of sampling or analytic equipment, and from inadvertent sources during sample collection, field processing, shipment, and laboratory analysis. Potential contamination bias, based on frequency and magnitude of detections in field blanks, is used to determine whether or under what conditions environmental data might need to be qualified for the interpretation of results in the context of comparisons with background levels, drinking-water standards, aquatic-life criteria or benchmarks, or human-health benchmarks. Environmental samples for which contamination bias as determined in this report applies are those from historical U.S. Geological Survey water-quality networks or programs that were collected during the same time frame and according to the same protocols and that were analyzed in the same laboratory as field blanks described in this report.Results from field blanks for ammonia, nitrite, nitrite plus nitrate, orthophosphate, and total phosphorus were partitioned by analytical method; results from the most commonly used analytical method for total phosphorus were further partitioned by date. Depending on the analytical method, 3.8, 9.2, or 26.9 percent of environmental samples, the last of these percentages pertaining to all results from 2007 through 2012, were potentially affected by ammonia contamination. Nitrite contamination potentially affected up to 2.6 percent of environmental samples collected between 2002 and 2006 and

  11. Novel Method for Measuring the Heat Collection Rate and Heat Loss Coefficient of Water-in-Glass Evacuated Tube Solar Water Heaters Based on Artificial Neural Networks and Support Vector Machine

    Directory of Open Access Journals (Sweden)

    Zhijian Liu

    2015-08-01

    Full Text Available The determinations of heat collection rate and heat loss coefficient are crucial for the evaluation of in service water-in-glass evacuated tube solar water heaters. However, the direct determination requires complex detection devices and a series of standard experiments, which also wastes too much time and manpower. To address this problem, we propose machine learning models including artificial neural networks (ANNs and support vector machines (SVM to predict the heat collection rate and heat loss coefficient without a direct determination. Parameters that can be easily obtained by “portable test instruments” were set as independent variables, including tube length, number of tubes, tube center distance, heat water mass in tank, collector area, final temperature and angle between tubes and ground, while the heat collection rate and heat loss coefficient determined by the detection device were set as dependent variables respectively. Nine hundred fifteen samples from in-service water-in-glass evacuated tube solar water heaters were used for training and testing the models. Results show that the multilayer feed-forward neural network (MLFN with 3 nodes is the best model for the prediction of heat collection rate and the general regression neural network (GRNN is the best model for the prediction of heat loss coefficient due to their low root mean square (RMS errors, short training times, and high prediction accuracies (under the tolerances of 30%, 20%, and 10%, respectively.

  12. Meteorological and oceanographic data collected from the National Data Buoy Center Coastal-Marine Automated Network (C-MAN) and moored (weather) buoys

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The National Data Buoy Center (NDBC) established the Coastal-Marine Automated Network (C-MAN) for the National Weather Service in the early 1980's. NDBC has...

  13. Real-Time Network Management

    National Research Council Canada - National Science Library

    Riolo, Joseph

    1998-01-01

    .... According to our Phase I research, it is possible to collect data on the network and morph it into queuing models to produce information about the network and physical layers of nodes on a network...

  14. Networks of networks – An introduction

    International Nuclear Information System (INIS)

    Kenett, Dror Y.; Perc, Matjaž; Boccaletti, Stefano

    2015-01-01

    Graphical abstract: Interdependent network reciprocity. Only those blue cooperative domains that are initially present on both networks survive. Abstract: This is an introduction to the special issue titled “Networks of networks” that is in the making at Chaos, Solitons & Fractals. Recent research and reviews attest to the fact that networks of networks are the next frontier in network science [1–7]. Not only are interactions limited and thus inadequately described by well-mixed models, it is also a fact that the networks that should be an integral part of such models are often interconnected, thus making the processes that are unfolding on them interdependent. From the World economy and transportation systems to social media, it is clear that processes taking place in one network might significantly affect what is happening in many other networks. Within an interdependent system, each type of interaction has a certain relevance and meaning, so that treating all the links identically inevitably leads to information loss. Networks of networks, interdependent networks, or multilayer networks are therefore a much better and realistic description of such systems, and this Special Issue is devoted to their structure, dynamics and evolution, as well as to the study of emergent properties in multi-layered systems in general. Topics of interest include but are not limited to the spread of epidemics and information, percolation, diffusion, synchronization, collective behavior, and evolutionary games on networks of networks. Interdisciplinary work on all aspects of networks of networks, regardless of background and motivation, is very welcome.

  15. Meteorology, physical oceanography, transport of water, biogeochemistry, and other parameters collected at fixed locations in the open ocean from the OceanSITES network

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This collection comprises data covering meteorology, physical oceanography, transport of water, biogeochemistry, and parameters relevant to the carbon cycle, ocean...

  16. Application of an Elman neural network to the problem of predicting the throughput of a petroleum collecting station; Previsao da vazao de uma estacao coletora de petroleo utilizando redes neurais de Elman

    Energy Technology Data Exchange (ETDEWEB)

    Paula, Wesley R. de [Universidade Federal de Campina Grande (UFCG), PB (Brazil). Curso de Pos-Graduacao em Informatica; Sousa, Andre G. de [Universidade Federal de Campina Grande (UFCG), PB (Brazil). Curso de Ciencia da Computacao; Gomes, Herman M.; Galvao, Carlos de O. [Universidade Federal de Campina Grande (UFCG), PB (Brazil)

    2004-07-01

    The objective of this paper is to present an initial study on the application of an Elman Neural Network to the problem of predicting the throughput of a petroleum collecting station. This study is part of a wider project, which aims at producing an automatic real-time system to remotely control a petroleum distribution pipeline, in such a way that optimum efficiency can be assured in terms of: (I) maximizing the volume of oil transported; and (II) minimizing energy consumption, risks of failures and damages to the environment. Experiments were carried out to determine the neural network parameters and to examine its performance under varying prediction times in the future. Promising results (with low MSE) have been obtained for predictions obtained up to 10 minutes in the future. (author)

  17. The Contribution of GIS to Display and Analyze the Water Quality Data Collected by a Wireless Sensor Network: Case of Bouregreg Catchment, Morocco

    Science.gov (United States)

    Boubakri, S.; Rhinane, H.

    2017-11-01

    The monitoring of water quality is, in most cases, managed in the laboratory and not on real time bases. Besides this process being lengthy, it doesn't provide the required specifications to describe the evolution of the quality parameters that are of interest. This study presents the integration of Geographic Information Systems (GIS) with wireless sensor networks (WSN) aiming to create a system able to detect the parameters like temperature, salinity and conductivity in a Moroccan catchment scale and transmit information to the support station. This Information is displayed and evaluated in a GIS using maps and spatial dashboard to monitor the water quality in real time.

  18. THE CONTRIBUTION OF GIS TO DISPLAY AND ANALYZE THE WATER QUALITY DATA COLLECTED BY A WIRELESS SENSOR NETWORK: CASE OF BOUREGREG CATCHMENT, MOROCCO

    Directory of Open Access Journals (Sweden)

    S. Boubakri

    2017-11-01

    Full Text Available The monitoring of water quality is, in most cases, managed in the laboratory and not on real time bases. Besides this process being lengthy, it doesn’t provide the required specifications to describe the evolution of the quality parameters that are of interest. This study presents the integration of Geographic Information Systems (GIS with wireless sensor networks (WSN aiming to create a system able to detect the parameters like temperature, salinity and conductivity in a Moroccan catchment scale and transmit information to the support station. This Information is displayed and evaluated in a GIS using maps and spatial dashboard to monitor the water quality in real time.

  19. The ecology of collective behavior.

    Directory of Open Access Journals (Sweden)

    Deborah M Gordon

    2014-03-01

    Full Text Available Similar patterns of interaction, such as network motifs and feedback loops, are used in many natural collective processes, probably because they have evolved independently under similar pressures. Here I consider how three environmental constraints may shape the evolution of collective behavior: the patchiness of resources, the operating costs of maintaining the interaction network that produces collective behavior, and the threat of rupture of the network. The ants are a large and successful taxon that have evolved in very diverse environments. Examples from ants provide a starting point for examining more generally the fit between the particular pattern of interaction that regulates activity, and the environment in which it functions.

  20. Health risks associated with biogas. Assessment of health risks related to the injection of biogas into the natural gas network. Affset opinion. Collective expertise report. Final version

    International Nuclear Information System (INIS)

    JAEG, Jean-Philippe; Bajeat, Philippe; Wenisch, Sandrine; Bellenfant, Gael; Godon, Jean-Jacques; Keck, Gerard; Lattes, Armand; Moletta-Denat, Marina; Naja, Ghinwa; Ramalho, Olivier; Zdanevitch, Isabelle; ALARY, Rene; RAMEL, Martine

    2008-10-01

    This publication reports a study which aimed at acquiring and analysing available bibliographical data regarding risks associated with the exposure to toxic compounds in relationship with the injection of biogas into the natural gas network, at characterising biogas composition and notably their content in potentially toxic compounds with respect to the currently distributed natural gas, at assessing health risks related to the exposure to toxic agents before and after combustion, also with respect to the currently distributed natural gas, and, based on this risk assessment, at determining biogas composition characteristics. Thus, after a presentation of the context, scope and modalities of this study, the report proposes an overview of various contextual aspects related to biogas (interest, production means, purification processes, valorisation, injection processes), the report discusses chemical risks related to biogas: bibliographical study, biogas chemical composition, chemical composition of biogas combustion residues. It also discusses microbiological risks. Several appendices are provided

  1. Linux Networking Cookbook

    CERN Document Server

    Schroder, Carla

    2008-01-01

    If you want a book that lays out the steps for specific Linux networking tasks, one that clearly explains the commands and configurations, this is the book for you. Linux Networking Cookbook is a soup-to-nuts collection of recipes that covers everything you need to know to perform your job as a Linux network administrator. You'll dive straight into the gnarly hands-on work of building and maintaining a computer network

  2. Prevalence of Chlamydia trachomatis, Trichomonas vaginalis and Neisseria gonorrhoeae Based on Data Collected by a Network of Clinical Microbiology Laboratories, in Italy.

    Science.gov (United States)

    Salfa, Maria Cristina; Suligoi, Barbara

    Bacterial and protozoal sexually transmitted infections (STIs), such as Chlamydia trachomatis, Trichomonas vaginalis and Neisseria gonorrhoeae, may cause acute symptoms, chronic infections and severe long-term complications. The complications of these infections in women include pelvic inflammatory disease, chronic pelvic pain, tubal infertility, ectopic pregnancy, and infertility. Moreover, infection during pregnancy is associated with premature rupture of the membranes, low birth weight and miscarriage.In Italy, Chlamydia trachomatis and Trichomonas vaginalis infections are not subject to mandatory reporting; while gonorrhoea is subject to mandatory reporting.To extend surveillance to STIs that are widespread yet often asymptomatic and to improve the knowledge on the epidemiology of these infections in Italy, in 2009 the "Centro Operativo AIDS of the Istituto Superiore di SanitÁ", in collaboration with the Association of Italian Clinical Microbiologists (AMCLI, Associazione Microbiologi Clinici Italiani), launched the sentinel STIs surveillance system based on a network of 13 clinical microbiology laboratories.The main objective of the surveillance was to assess the prevalence and risk factors associated with Chlamydia trachomatis, Trichomonas vaginalis and Neisseria gonorrhoea infections among individuals attending microbiology laboratories in Italy.

  3. Information theoretic description of networks

    Science.gov (United States)

    Wilhelm, Thomas; Hollunder, Jens

    2007-11-01

    We present a new information theoretic approach for network characterizations. It is developed to describe the general type of networks with n nodes and L directed and weighted links, i.e., it also works for the simpler undirected and unweighted networks. The new information theoretic measures for network characterizations are based on a transmitter-receiver analogy of effluxes and influxes. Based on these measures, we classify networks as either complex or non-complex and as either democracy or dictatorship networks. Directed networks, in particular, are furthermore classified as either information spreading and information collecting networks. The complexity classification is based on the information theoretic network complexity measure medium articulation (MA). It is proven that special networks with a medium number of links ( L∼n1.5) show the theoretical maximum complexity MA=(log n)2/2. A network is complex if its MA is larger than the average MA of appropriately randomized networks: MA>MAr. A network is of the democracy type if its redundancy Rdictatorship network. In democracy networks all nodes are, on average, of similar importance, whereas in dictatorship networks some nodes play distinguished roles in network functioning. In other words, democracy networks are characterized by cycling of information (or mass, or energy), while in dictatorship networks there is a straight through-flow from sources to sinks. The classification of directed networks into information spreading and information collecting networks is based on the conditional entropies of the considered networks ( H(A/B)=uncertainty of sender node if receiver node is known, H(B/A)=uncertainty of receiver node if sender node is known): if H(A/B)>H(B/A), it is an information collecting network, otherwise an information spreading network. Finally, different real networks (directed and undirected, weighted and unweighted) are classified according to our general scheme.

  4. Collective proposal of Contingency Plan as an alternative for management risks to socioenvironmental disasters within Network Management Risk of Córrego Dantas (REGER-CD), Nova Friburgo, State of Rio de Janeiro, Brazil

    Science.gov (United States)

    Freitas, Leonardo; Luiza Coelho Netto, Ana

    2017-04-01

    An extreme rainfall event took place in the Mountainous Region of the state of Rio de Janeiro in January 2011, causing a catastrophic landslide that resulted in more than 900 deaths and 350 people disappearances. Precipitation events associated with landslides are common in this region and climate change tends to increase the frequency of intense rains and, consequently, landslides. At the same time, the vulnerability of communities has increased as a result of disorderly urban growth. Despite that, before 2011 communities and public power were not prepared to disaster management..After the 2011 event, public authorities try to established policies to reduce these vulnerabilities. One of the communities where the government acted was Córrego Dantas. However, the actions in this place were carried out in a top-down model, without discussion with population. As a consequence, the performance of public power has amplified social vulnerabilities. Highlight for the truculent removal of residents; resettlement in geographically isolated housing complexes; and the establishment of urbanization policies that go against the interests of the residents. The construction of the Córrego d'Aantas Disaster Risk Management Network (REGER-CD), including residents of affected communities, researchers, NGO members and representatives of the public power, is one way to respond these questions. Within this network, the construction of a proposal for a collective contingency plan, articulated with the municipal contingency plan, is generating residents' empowerment, greater adaptation to risks and reducing the vulnerability of Disasters and mass movements

  5. Collective Improvisation

    Directory of Open Access Journals (Sweden)

    Clare M. Cooper

    2016-08-01

    Full Text Available Collective improvisation as a creative practice is intensely social, trusting, unpopular, anti-hierarchical and, for these reasons, political. Cooper describes the risks and rich rewards of improvising with fellow artists and identifies the parallels between improvising ensembles of musicians in Australia with the collectively painted protest banners of the Taring Padi Collective in Indonesia after a brief visit to Jogjakarta.

  6. Cooperative and supportive neural networks

    International Nuclear Information System (INIS)

    Sree Hari Rao, V.; Raja Sekhara Rao, P.

    2007-01-01

    This Letter deals with the concepts of co-operation and support among neurons existing in a network which contribute to their collective capabilities and distributed operations. Activational dynamical properties of these networks are discussed

  7. Wavelet analysis of the LF radio signals collected by the European VLF/LF network from July 2009 to April 2011

    Directory of Open Access Journals (Sweden)

    Michael E. Contadakis

    2012-04-01

    Full Text Available

    In 2008, a radio receiver that works in very low frequency (VLF; 20-60 kHz and LF (150-300 kHz bands was developed by an Italian factory. The receiver can monitor 10 frequencies distributed in these bands, with the measurement for each of them of the electric field intensity. Since 2009, to date, six of these radio receivers have been installed throughout Europe to establish a ‘European VLF/LF Network’. At present, two of these are into operation in Italy, and the remaining four are located in Greece, Turkey, Portugal and Romania. For the present study, the LF radio data collected over about two years were analysed. At first, the day-time data and the night-time data were separated for each radio signal. Taking into account that the LF signals are characterized by ground-wave and sky-wave propagation modes, the day-time data are related to the ground wave and the night-time data to the sky wave. In this framework, the effects of solar activity and storm activity were defined in the different trends. Then, the earthquakes with M ≥5.0 that occurred over the same period were selected, as those located in a 300-km radius around each receiver/transmitter and within the 5th Fresnel zone related to each transmitter-receiver path. Where possible, the wavelet analysis was applied on the time series of the radio signal intensity, and some anomalies related to previous earthquakes were revealed. Except for some doubt in one case, success appears to have been obtained in all of the cases related to the 300 km circles in for the ground waves and the sky waves. For the Fresnel cases, success in two cases and one failure were seen in analysing the sky waves. The failure occurred in August/September, and might be related to the disturbed conditions of the ionosphere in summer.

     

  8. Computer-communication networks

    CERN Document Server

    Meditch, James S

    1983-01-01

    Computer- Communication Networks presents a collection of articles the focus of which is on the field of modeling, analysis, design, and performance optimization. It discusses the problem of modeling the performance of local area networks under file transfer. It addresses the design of multi-hop, mobile-user radio networks. Some of the topics covered in the book are the distributed packet switching queuing network design, some investigations on communication switching techniques in computer networks and the minimum hop flow assignment and routing subject to an average message delay constraint

  9. Learning Networks, Networked Learning

    NARCIS (Netherlands)

    Sloep, Peter; Berlanga, Adriana

    2010-01-01

    Sloep, P. B., & Berlanga, A. J. (2011). Learning Networks, Networked Learning [Redes de Aprendizaje, Aprendizaje en Red]. Comunicar, XIX(37), 55-63. Retrieved from http://dx.doi.org/10.3916/C37-2011-02-05

  10. Culture collections.

    Science.gov (United States)

    Smith, David

    2012-01-01

    Culture collections no matter their size, form, or institutional objectives play a role in underpinning microbiology, supplying the resources for study, innovation, and discovery. Their basic roles include providing a mechanism for ex situ conservation of organisms; they are repositories for strains subject to publication, taking in safe, confidential, and patent deposits from researchers. They supply strains for use; therefore, the microorganisms provided must be authentic and preserved well, and any associated information must be valid and sufficient to facilitate the confirmation of their identity and to facilitate their use. The organisms must be collected in compliance with international conventions, international and national legislation and distributed to users indicating clearly the terms and conditions under which they are received and can be used. Collections are harmonizing approaches and characterizing strains to meet user needs. No one single collection can carry out this task alone, and therefore, it is important that output and strategy are coordinated to ensure culture collections deliver the basic resources and services microbiological innovation requires. This chapter describes the types of collection and how they can implement quality management systems and operate to deliver their basic functions. The links to information sources given not only provide support for the practitioners within collections but also provide guidance to users on accessing the huge resource available and how they can help ensure microbiology has the resources and a solid platform for future development. Copyright © 2012 Elsevier Inc. All rights reserved.

  11. Integrating networks with Mathematica

    NARCIS (Netherlands)

    Strijkers, R.J.; Meijer, R.J.

    2008-01-01

    We have developed a concept that considers network behavior as a collection of software objects, which can be used or modified in computer programs. The interfaces of these software objects are exposed as web services and enable applications to analyze and manipulate networks, e.g. to find

  12. Home area networks

    NARCIS (Netherlands)

    Koonen, A.M.J.

    2013-01-01

    This article consists of a collection of slides from the author's conference presentation. Some of the specific areas/topics discussed include: Convergence in home networks, home service scenarios; Home wired network architectures, CapEx and OpEx; Residential Gateway; Optical fiber types;

  13. Collective Efficacy

    DEFF Research Database (Denmark)

    Chen, Ying; Zhou, Xiaohu; Klyver, Kim

    2018-01-01

    at manufacturing companies show that benevolent leadership and moral leadership, both components of paternalistic leadership, are positively related to organizational commitment and further that collective efficacy mediates the moral leadership–organizational commitment relationship. We did not find a relationship...... between authoritarian leadership and organizational commitment. Besides, it was found that team cohesion negatively moderates the relationship between moral leadership and collective efficacy and positively moderates the relationship between collective efficacy and organizational commitment. Explanations......Based on social cognitive theory, we theorize that collective efficacy plays a mediating role in the relationship between paternalistic leadership and organizational commitment and that this mediating role depends on team cohesion. The empirical results from a study of 238 employees from 52 teams...

  14. Collective Travel Planning in Spatial Networks

    KAUST Repository

    Shang, Shuo; Chen, Lisi; Wei, Zhewei; Jensen, Christian; Wen, Ji-Rong; Kalnis, Panos

    2015-01-01

    meeting points. When multiple travelers target the same destination (e.g., a stadium or a theater), they may want to assemble at meeting points and then go together to the destination by public transport to reduce their global travel cost (e.g., energy

  15. Sustainable Operation of Arterial Networks

    Science.gov (United States)

    2017-07-14

    This report describes operational data analysis and modeling of arterial networks with signalized intersections as follows: The setup for data collection, analysis and simulation is presented in Section 2.1. Detailed analysis of collected signal phas...

  16. A Survey of Collectives

    Science.gov (United States)

    Tumer, Kagan; Wolpert, David

    2004-01-01

    Due to the increasing sophistication and miniaturization of computational components, complex, distributed systems of interacting agents are becoming ubiquitous. Such systems, where each agent aims to optimize its own performance, but where there is a well-defined set of system-level performance criteria, are called collectives. The fundamental problem in analyzing/designing such systems is in determining how the combined actions of self-interested agents leads to 'coordinated' behavior on a iarge scale. Examples of artificial systems which exhibit such behavior include packet routing across a data network, control of an array of communication satellites, coordination of multiple deployables, and dynamic job scheduling across a distributed computer grid. Examples of natural systems include ecosystems, economies, and the organelles within a living cell. No current scientific discipline provides a thorough understanding of the relation between the structure of collectives and how well they meet their overall performance criteria. Although still very young, research on collectives has resulted in successes both in understanding and designing such systems. It is eqected that as it matures and draws upon other disciplines related to collectives, this field will greatly expand the range of computationally addressable tasks. Moreover, in addition to drawing on them, such a fully developed field of collective intelligence may provide insight into already established scientific fields, such as mechanism design, economics, game theory, and population biology. This chapter provides a survey to the emerging science of collectives.

  17. 77 FR 13135 - Agency Information Collection Activities: Submission for Review; Information Collection Request...

    Science.gov (United States)

    2012-03-05

    ... and network operational data for use in cyber security research and development through the... collection: Department of Homeland Security, Science & Technology Directorate, Cyber Security Division (CSD... DEPARTMENT OF HOMELAND SECURITY [Docket No. DHS-2012-0006] Agency Information Collection...

  18. Collective Security

    DEFF Research Database (Denmark)

    Galster, Kjeld

    in worldwide market conditions left perceptible ripples in Danish economy, budget discussions grew in importance over this period. The pacifist stance entailed disinclination to accept that the collective security concept and international treaties and accords signed by Denmark should necessitate credible...... and other international treaties provided arguments for adjusting the foreign and security policy ambitions, and since the general flux in worldwide market conditions left perceptible ripples in Danish economy, budget discussions grew in importance over this period. The pacifist stance entailed......Collective Security: National Egotism (Abstract) In Danish pre-World War I defence debate the notion of collective security is missing. During the early years of the 19th century, the political work is influenced by a pervasive feeling of rising tension and danger on the continent of Europe...

  19. Locals Collection

    Directory of Open Access Journals (Sweden)

    Stephen Hastings-King

    2010-03-01

    Full Text Available A locals collection is a set of parameters that are used to delimit data-mining operations. This piece uses a collection of locals from around Essex Massachusetts to shape and delimit an interrogation of post-reality in contemporary America. It explores the notion of crisis, the possibility of a crisis of empire that may or may not emerge in a media-space that does not allow crisis of empire to be mentioned and relations this maybe-crisis to the various levels of economic dysfunction that have become evident since late 2008. But mostly this piece explores ways in which particular stories about particular people do and do not link/link to these larger-scale narratives. This is the first of a potential series of locals collections that will mine the American post-real.

  20. North and South Pacific Ocean Temperature Profile Data for the High Resolution XBT Network for PX37, PX10, and PX44 were collected by the Scripps Institute of Oceanography from March 2001 to June 2009 (NODC Accession 0056790)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Physical data were collected from XBT casts from the North and South Pacific Oceans. Data were collected from March 2001 to June 2009. Data were collected and...

  1. Concurrent Collections

    OpenAIRE

    Budimlić, Zoran; Burke, Michael; Cavé, Vincent; Knobe, Kathleen; Lowney, Geoff; Newton, Ryan; Palsberg, Jens; Peixotto, David; Sarkar, Vivek; Schlimbach, Frank; Taşırlar, Sağnak

    2010-01-01

    We introduce the Concurrent Collections (CnC) programming model. CnC supports flexible combinations of task and data parallelism while retaining determinism. CnC is implicitly parallel, with the user providing high-level operations along with semantic ordering constraints that together form a CnC graph. We formally describe the execution semantics of CnC and prove that the model guarantees deterministic computation. We evaluate the performance of CnC implementations on several applications an...

  2. Early diagnosis and monitoring of mucormycosis by detection of circulating DNA in serum: retrospective analysis of 44 cases collected through the French Surveillance Network of Invasive Fungal Infections (RESSIF).

    Science.gov (United States)

    Millon, L; Herbrecht, R; Grenouillet, F; Morio, F; Alanio, A; Letscher-Bru, V; Cassaing, S; Chouaki, T; Kauffmann-Lacroix, C; Poirier, P; Toubas, D; Augereau, O; Rocchi, S; Garcia-Hermoso, D; Bretagne, S

    2016-09-01

    The main objective of this study was to assess the diagnostic performance of a set of three Mucorales quantitative PCR assays in a retrospective multicentre study. Mucormycosis cases were recorded thanks to the French prospective surveillance programme (RESSIF network). The day of sampling of the first histological or mycological positive specimen was defined as day 0 (D0). Detection of circulating DNA was performed on frozen serum samples collected from D-30 to D30, using quantitative PCR assays targeting Rhizomucor, Lichtheimia, Mucor/Rhizopus. Forty-four patients diagnosed with probable (n = 19) or proven (n = 25) mucormycosis were included. Thirty-six of the 44 patients (81%) had at least one PCR-positive serum. The first PCR-positive sample was observed 9 days (range 0-28 days) before diagnosis was made using mycological criteria and at least 2 days (range 0-24 days) before imaging. The identifications provided with the quantitative PCR assays were all concordant with culture and/or PCR-based identification of the causal species. Survival rate at D84 was significantly higher for patients with an initially positive PCR that became negative after treatment initiation than for patients whose PCR remained positive (48% and 4%, respectively; p Mucorales quantitative PCR could not only confirm the mucormycosis diagnosis when other mycological arguments were present but could also anticipate this diagnosis. Quantification of DNA loads may also be a useful adjunct to treatment monitoring. Copyright © 2015 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

  3. Collective action, clientelism and connectivity

    DEFF Research Database (Denmark)

    Shami, Mahvish

    that the unequal relationship between landlords and peasants does not, in and by itself, block peasant collective action. Rather, it is the interaction between clientelism and isolation that allow patrons to block community based projects. Despite still relying on powerful landlords, peasants in connected villages...... face no such constraints. On the contrary, their patrons assisted them in their collective endeavours, making the hierarchical network an added resource for peasants to rely upon....

  4. Tropical Plant Collections

    DEFF Research Database (Denmark)

    Friis, Ib; Balslev, Henrik

    that involved Germany, Britain and France, until independence, which was brightened by exemplary collaboration. Muasya focussed on South Africa, which is the most developed country in sub-Saharan Africa with a well-functioning network of herbaria that covers widely different biota. Sanjappa outlined the history...... crisis. Friis gave a broad overview of the history of herbaria and botanical gardens and the changing conceptual frameworks behind their existence. Baldini talked about early Italian botanical collectors and the fate of their collections. Baas accounted for the Golden Age of Dutch botany during pre......-colonial and early colonial periods. With the presentation by Cribb on the botany of the British Empire we were fully into the colonial period, focussing on the Royal Botanic Gardens at Kew. The situation in North America was treated by Funk, who illustrated the development of collections of tropical plants...

  5. Declarative Networking

    CERN Document Server

    Loo, Boon Thau

    2012-01-01

    Declarative Networking is a programming methodology that enables developers to concisely specify network protocols and services, which are directly compiled to a dataflow framework that executes the specifications. Declarative networking proposes the use of a declarative query language for specifying and implementing network protocols, and employs a dataflow framework at runtime for communication and maintenance of network state. The primary goal of declarative networking is to greatly simplify the process of specifying, implementing, deploying and evolving a network design. In addition, decla

  6. Collective Success or Collective Failure?

    DEFF Research Database (Denmark)

    Fayyaz, Anjum

    study of soccer village project to learn how various attempts at facilitating joint CSR action in the Pakistani football manufacturing have consistently failed in addressing international CSR compliance demands. I conclude that this form of collective failure – along with technological changes, lack...... of innovation, and government failure - can partly explain why Sialkot has been marginalized in terms of its overall share of world football manufacturing in the last decade....

  7. The STARLINK software collection

    Science.gov (United States)

    Penny, A. J.; Wallace, P. T.; Sherman, J. C.; Terret, D. L.

    1993-12-01

    A demonstration will be given of some recent Starlink software. STARLINK is: a network of computers used by UK astronomers; a collection of programs for the calibration and analysis of astronomical data; a team of people giving hardware, software and administrative support. The Starlink Project has been in operation since 1980 to provide UK astronomers with interactive image processing and data reduction facilities. There are now Starlink computer systems at 25 UK locations, serving about 1500 registered users. The Starlink software collection now has about 25 major packages covering a wide range of astronomical data reduction and analysis techniques, as well as many smaller programs and utilities. At the core of most of the packages is a common `software environment', which provides many of the functions which applications need and offers standardized methods of structuring and accessing data. The software environment simplifies programming and support, and makes it easy to use different packages for different stages of the data reduction. Users see a consistent style, and can mix applications without hitting problems of differing data formats. The Project group coordinates the writing and distribution of this software collection, which is Unix based. Outside the UK, Starlink is used at a large number of places, which range from installations at major UK telescopes, which are Starlink-compatible and managed like Starlink sites, to individuals who run only small parts of the Starlink software collection.

  8. Network cohesion

    OpenAIRE

    Cavalcanti, Tiago Vanderlei; Giannitsarou, Chrysi; Johnson, CR

    2017-01-01

    We define a measure of network cohesion and show how it arises naturally in a broad class of dynamic models of endogenous perpetual growth with network externalities. Via a standard growth model, we show why network cohesion is crucial for conditional convergence and explain that as cohesion increases, convergence is faster. We prove properties of network cohesion and define a network aggregator that preserves network cohesion.

  9. The network researchers' network

    DEFF Research Database (Denmark)

    Henneberg, Stephan C.; Jiang, Zhizhong; Naudé, Peter

    2009-01-01

    The Industrial Marketing and Purchasing (IMP) Group is a network of academic researchers working in the area of business-to-business marketing. The group meets every year to discuss and exchange ideas, with a conference having been held every year since 1984 (there was no meeting in 1987). In thi......The Industrial Marketing and Purchasing (IMP) Group is a network of academic researchers working in the area of business-to-business marketing. The group meets every year to discuss and exchange ideas, with a conference having been held every year since 1984 (there was no meeting in 1987......). In this paper, based upon the papers presented at the 22 conferences held to date, we undertake a Social Network Analysis in order to examine the degree of co-publishing that has taken place between this group of researchers. We identify the different components in this database, and examine the large main...

  10. Emerging wireless networks concepts, techniques and applications

    CERN Document Server

    Makaya, Christian

    2011-01-01

    An authoritative collection of research papers and surveys, Emerging Wireless Networks: Concepts, Techniques, and Applications explores recent developments in next-generation wireless networks (NGWNs) and mobile broadband networks technologies, including 4G (LTE, WiMAX), 3G (UMTS, HSPA), WiFi, mobile ad hoc networks, mesh networks, and wireless sensor networks. Focusing on improving the performance of wireless networks and provisioning better quality of service and quality of experience for users, it reports on the standards of different emerging wireless networks, applications, and service fr

  11. Optical Access Networks

    Science.gov (United States)

    Zheng, Jun; Ansari, Nirwan

    2005-06-01

    are now underway this hot area. The purpose of this feature issue is to expose the networking community to the latest research breakthroughs and progresses in the area of optical access networks. This feature issue aims to present a collection of papers that focus on the state-of-the-art research in various networking aspects of optical access networks. Original papers are solicited from all researchers involved in area of optical access networks. Topics of interest include but not limited to: Optical access network architectures and protocols Passive optical networks (BPON, EPON, GPON, etc.) Active optical networks Multiple access control Multiservices and QoS provisioning Network survivability Field trials and standards Performance modeling and analysis

  12. From Offline Social Networks to Online Social Networks: Changes in Entrepreneurship

    Directory of Open Access Journals (Sweden)

    Yang SONG

    2015-01-01

    Full Text Available The paper reviewed studies of entrepreneurship based on the emergency of online social networks. Similar to offline social networks, entrepreneurs’ online social networks have their own unique characteristics. We first reviewed the offline network based research on entrepreneurship. Then we reviewed the studies of entrepreneurship in the context of online social networks including those focusing on topics of network structures and network ties. We highlighted online network communities based on the data collected from LinkedIn, Facebook and Twitter. Our research implies that both researcher and entrepreneurs are facing new opportunities due to the emergence of online social networks.

  13. Collection Metadata Solutions for Digital Library Applications

    Science.gov (United States)

    Hill, Linda L.; Janee, Greg; Dolin, Ron; Frew, James; Larsgaard, Mary

    1999-01-01

    Within a digital library, collections may range from an ad hoc set of objects that serve a temporary purpose to established library collections intended to persist through time. The objects in these collections vary widely, from library and data center holdings to pointers to real-world objects, such as geographic places, and the various metadata schemas that describe them. The key to integrated use of such a variety of collections in a digital library is collection metadata that represents the inherent and contextual characteristics of a collection. The Alexandria Digital Library (ADL) Project has designed and implemented collection metadata for several purposes: in XML form, the collection metadata "registers" the collection with the user interface client; in HTML form, it is used for user documentation; eventually, it will be used to describe the collection to network search agents; and it is used for internal collection management, including mapping the object metadata attributes to the common search parameters of the system.

  14. Maintenance of family networks

    DEFF Research Database (Denmark)

    marsico, giuseppina; Chaudhary, N; Valsiner, Jaan

    2015-01-01

    Families are social units that expand in time (across generations) and space (as a geographically distributed sub-structures of wider kinship networks). Understanding of intergenerational family relations thus requires conceptualization of communication processes that take place within a small...... collective of persons linked with one another by a flexible social network. Within such networks, Peripheral Communication Patterns set the stage for direct everyday life activities within the family context. Peripheral Communication Patterns are conditions where one family network member (A) communicates...... manifestly with another member (B) with the aim of bringing the communicative message to the third member (C) who is present but is not explicitly designated as the manifest addressee of the intended message. Inclusion of physically non-present members of the family network (elders living elsewhere, deceased...

  15. Complex Networks IX

    CERN Document Server

    Coronges, Kate; Gonçalves, Bruno; Sinatra, Roberta; Vespignani, Alessandro; Proceedings of the 9th Conference on Complex Networks; CompleNet 2018

    2018-01-01

    This book aims to bring together researchers and practitioners working across domains and research disciplines to measure, model, and visualize complex networks. It collects the works presented at the 9th International Conference on Complex Networks (CompleNet) 2018 in Boston, MA in March, 2018. With roots in physical, information and social science, the study of complex networks provides a formal set of mathematical methods, computational tools and theories to describe prescribe and predict dynamics and behaviors of complex systems. Despite their diversity, whether the systems are made up of physical, technological, informational, or social networks, they share many common organizing principles and thus can be studied with similar approaches. This book provides a view of the state-of-the-art in this dynamic field and covers topics such as group decision-making, brain and cellular connectivity, network controllability and resiliency, online activism, recommendation systems, and cyber security.

  16. VRML metabolic network visualizer.

    Science.gov (United States)

    Rojdestvenski, Igor

    2003-03-01

    A successful date collection visualization should satisfy a set of many requirements: unification of diverse data formats, support for serendipity research, support of hierarchical structures, algorithmizability, vast information density, Internet-readiness, and other. Recently, virtual reality has made significant progress in engineering, architectural design, entertainment and communication. We experiment with the possibility of using the immersive abstract three-dimensional visualizations of the metabolic networks. We present the trial Metabolic Network Visualizer software, which produces graphical representation of a metabolic network as a VRML world from a formal description written in a simple SGML-type scripting language.

  17. Data Exchange Network

    DEFF Research Database (Denmark)

    Grau Larsen, Anton; Ellersgaard, Christoph

    2015-01-01

    This article presents the extensive Danish elite network. Collected during 2012 and 2013, the data comprises 56,536 positions within 5,079 affiliations, and connects 37,750 individuals. The network consists of the largest Danish corporations, state institutions, NGO’s, and other integrative...... networks such as social clubs or royal events. Data were gathered through an inclusion principle, adding all potentially interesting affiliations. Procedures of name-matching and quality control are presented. Finally, the data are introduced: made available through a package for R, which enables...

  18. Wireless rechargeable sensor networks

    CERN Document Server

    Yang, Yuanyuan

    2015-01-01

    This SpringerBrief provides a concise guide to applying wireless energy transfer techniques in traditional battery-powered sensor networks. It examines the benefits and challenges of wireless power including efficiency and reliability. The authors build a wireless rechargeable sensor networks from scratch and aim to provide perpetual network operation. Chapters cover a wide range of topics from the collection of energy information and recharge scheduling to joint design with typical sensing applications such as data gathering. Problems are approached using a natural combination of probability

  19. Network cosmology.

    Science.gov (United States)

    Krioukov, Dmitri; Kitsak, Maksim; Sinkovits, Robert S; Rideout, David; Meyer, David; Boguñá, Marián

    2012-01-01

    Prediction and control of the dynamics of complex networks is a central problem in network science. Structural and dynamical similarities of different real networks suggest that some universal laws might accurately describe the dynamics of these networks, albeit the nature and common origin of such laws remain elusive. Here we show that the causal network representing the large-scale structure of spacetime in our accelerating universe is a power-law graph with strong clustering, similar to many complex networks such as the Internet, social, or biological networks. We prove that this structural similarity is a consequence of the asymptotic equivalence between the large-scale growth dynamics of complex networks and causal networks. This equivalence suggests that unexpectedly similar laws govern the dynamics of complex networks and spacetime in the universe, with implications to network science and cosmology.

  20. The Analysis of Duocentric Social Networks: A Primer.

    Science.gov (United States)

    Kennedy, David P; Jackson, Grace L; Green, Harold D; Bradbury, Thomas N; Karney, Benjamin R

    2015-02-01

    Marriages and other intimate partnerships are facilitated or constrained by the social networks within which they are embedded. To date, methods used to assess the social networks of couples have been limited to global ratings of social network characteristics or network data collected from each partner separately. In the current article, the authors offer new tools for expanding on the existing literature by describing methods of collecting and analyzing duocentric social networks, that is, the combined social networks of couples. They provide an overview of the key considerations for measuring duocentric networks, such as how and why to combine separate network interviews with partners into one shared duocentric network, the number of network members to assess, and the implications of different network operationalizations. They illustrate these considerations with analyses of social network data collected from 57 low-income married couples, presenting visualizations and quantitative measures of network composition and structure.

  1. Collective biogas plants

    International Nuclear Information System (INIS)

    1992-01-01

    Papers contributed to the European seminar on collective biogas plants held at Herning, Denmark on October 22-23 under the auspices of the Commission of the European Communities, Directorate-General for Energy (DG XVII) are presented. Within the framework of the THERMIE programme, a network of OPETs (Organizations for the Promotion of Energy Technologies) was set up in order to disseminate information on new energy technologies throughout the European communities. The potential for further implementation of centralized capacity for the conversion of animal manures and other organic wastes to bio-fuels, not only in central and eastern Europe but also in the developing countries, is discussed in addition to the relevant technologies. Actual biomass conversion plants are described and details are given on operational experience and plant management. Agricultural, economic and policy aspects are also dealt with. (AB)

  2. Adverse Outcome Pathway Networks II: Network Analytics.

    Science.gov (United States)

    Villeneuve, Daniel L; Angrish, Michelle M; Fortin, Marie C; Katsiadaki, Ioanna; Leonard, Marc; Margiotta-Casaluci, Luigi; Munn, Sharon; O'Brien, Jason M; Pollesch, Nathan L; Smith, L Cody; Zhang, Xiaowei; Knapen, Dries

    2018-02-28

    Toxicological responses to stressors are more complex than the simple one biological perturbation to one adverse outcome model portrayed by individual adverse outcome pathways (AOPs). Consequently, the AOP framework was designed to facilitate de facto development of AOP networks that can aid understanding and prediction of pleiotropic and interactive effects more common to environmentally realistic, complex exposure scenarios. The present paper introduces nascent concepts related to the qualitative analysis of AOP networks. First, graph theory-based approaches for identifying important topological features are illustrated using two example AOP networks derived from existing AOP descriptions. Second, considerations for identifying the most significant path(s) through an AOP network from either a biological or risk assessment perspective are described. Finally, approaches for identifying interactions among AOPs that may result in additive, synergistic, or antagonistic responses, or previously undefined emergent patterns of response, are introduced. Along with a companion article (Knapen et al. part I), these concepts set the stage for development of tools and case studies that will facilitate more rigorous analysis of AOP networks, and the utility of AOP network-based predictions, for use in research and regulatory decision-making. Collectively, this work addresses one of the major themes identified through a SETAC Horizon Scanning effort focused on advancing the AOP framework. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  3. A rede de sustentação coletiva, espaço potencial e resgate identitário: projeto mãe-criadeira The collective support network, a potential space for identity recovery: the nursing mother project

    Directory of Open Access Journals (Sweden)

    Marco Antonio Chagas Guimarães

    2008-03-01

    concept of traumatic conflictive situations in order to give visibility to this effort, which is not observable concretely, in view of its psychological nature. Through the Mãe-Criadeira (Nursing Mother Project experience, developed in the communities of Vigario Geral and Parada de Lucas (Rio de Janeiro, and directed at black and non-black pregnant women, the idea of the Collective Support Network is presented as an intervention strategy, contributing to lessen the harmful effects of racism in this women population.

  4. Telecommunication networks

    CERN Document Server

    Iannone, Eugenio

    2011-01-01

    Many argue that telecommunications network infrastructure is the most impressive and important technology ever developed. Analyzing the telecom market's constantly evolving trends, research directions, infrastructure, and vital needs, Telecommunication Networks responds with revolutionized engineering strategies to optimize network construction. Omnipresent in society, telecom networks integrate a wide range of technologies. These include quantum field theory for the study of optical amplifiers, software architectures for network control, abstract algebra required to design error correction co

  5. Sea Turtle Stranding Network Reports

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Sea Turtle Stranding and Salvage Network (STSSN) was formally established in 1980 to collect information on and document the stranding of marine turtles along...

  6. Temporal networks

    CERN Document Server

    Saramäki, Jari

    2013-01-01

    The concept of temporal networks is an extension of complex networks as a modeling framework to include information on when interactions between nodes happen. Many studies of the last decade examine how the static network structure affect dynamic systems on the network. In this traditional approach  the temporal aspects are pre-encoded in the dynamic system model. Temporal-network methods, on the other hand, lift the temporal information from the level of system dynamics to the mathematical representation of the contact network itself. This framework becomes particularly useful for cases where there is a lot of structure and heterogeneity both in the timings of interaction events and the network topology. The advantage compared to common static network approaches is the ability to design more accurate models in order to explain and predict large-scale dynamic phenomena (such as, e.g., epidemic outbreaks and other spreading phenomena). On the other hand, temporal network methods are mathematically and concept...

  7. Innovation in the collective brain

    Science.gov (United States)

    Muthukrishna, Michael; Henrich, Joseph

    2016-01-01

    Innovation is often assumed to be the work of a talented few, whose products are passed on to the masses. Here, we argue that innovations are instead an emergent property of our species' cultural learning abilities, applied within our societies and social networks. Our societies and social networks act as collective brains. We outline how many human brains, which evolved primarily for the acquisition of culture, together beget a collective brain. Within these collective brains, the three main sources of innovation are serendipity, recombination and incremental improvement. We argue that rates of innovation are heavily influenced by (i) sociality, (ii) transmission fidelity, and (iii) cultural variance. We discuss some of the forces that affect these factors. These factors can also shape each other. For example, we provide preliminary evidence that transmission efficiency is affected by sociality—languages with more speakers are more efficient. We argue that collective brains can make each of their constituent cultural brains more innovative. This perspective sheds light on traits, such as IQ, that have been implicated in innovation. A collective brain perspective can help us understand otherwise puzzling findings in the IQ literature, including group differences, heritability differences and the dramatic increase in IQ test scores over time. PMID:26926282

  8. Network maintenance

    CERN Multimedia

    GS Department

    2009-01-01

    A site-wide network maintenance operation has been scheduled for Saturday 28 February. Most of the network devices of the general purpose network will be upgraded to a newer software version, in order to improve our network monitoring capabilities. This will result in a series of short (2-5 minutes) random interruptions everywhere on the CERN sites throughout the day. This upgrade will not affect the Computer Centre itself, Building 613, the Technical Network and the LHC experiments, dedicated networks at the pits. For further details of this intervention, please contact Netops by phone 74927 or e-mail mailto:Netops@cern.ch. IT/CS Group

  9. Network maintenance

    CERN Multimedia

    IT Department

    2009-01-01

    A site wide network maintenance has been scheduled for Saturday 28 February. Most of the network devices of the General Purpose network will be upgraded to a newer software version, in order to improve our network monitoring capabilities. This will result in a series of short (2-5 minutes) random interruptions everywhere on the CERN sites along this day. This upgrade will not affect: the Computer centre itself, building 613, the Technical Network and the LHC experiments dedicated networks at the pits. Should you need more details on this intervention, please contact Netops by phone 74927 or email mailto:Netops@cern.ch. IT/CS Group

  10. Cluster emergence and network evolution A longitudinal analysis of the inventor network in Sophia-Antipolis

    OpenAIRE

    Anne L. J. ter Wal

    2008-01-01

    Abstract It is increasingly acknowledged that clusters do not necessarily exhibit networks of local collective learning. This paper addresses the question under which conditions this is the case. Through a longitudinal case study of the business park Sophia-Antipolis it investigates how networks of collective learning emerged throughout the growth of the cluster. Network reconstruction with patent data shows that an innovation network emerged only in Information Technology, in whic...

  11. Network Ambivalence

    Directory of Open Access Journals (Sweden)

    Patrick Jagoda

    2015-08-01

    Full Text Available The language of networks now describes everything from the Internet to the economy to terrorist organizations. In distinction to a common view of networks as a universal, originary, or necessary form that promises to explain everything from neural structures to online traffic, this essay emphasizes the contingency of the network imaginary. Network form, in its role as our current cultural dominant, makes scarcely imaginable the possibility of an alternative or an outside uninflected by networks. If so many things and relationships are figured as networks, however, then what is not a network? If a network points towards particular logics and qualities of relation in our historical present, what others might we envision in the future? In  many ways, these questions are unanswerable from within the contemporary moment. Instead of seeking an avant-garde approach (to move beyond networks or opting out of networks (in some cases, to recover elements of pre-networked existence, this essay proposes a third orientation: one of ambivalence that operates as a mode of extreme presence. I propose the concept of "network aesthetics," which can be tracked across artistic media and cultural forms, as a model, style, and pedagogy for approaching interconnection in the twenty-first century. The following essay is excerpted from Network Ambivalence (Forthcoming from University of Chicago Press. 

  12. Physical profile data collected in the Equatorial Pacific during cruises to service the TAO array, a network of deep ocean moored buoys, from 2007-04-07 to the present

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — As part of the Tropical Atmosphere Ocean (TAO) Program, the National Data Buoy Center (NDBC) was responsible for the at-sea collection, quality control and...

  13. Network workshop

    DEFF Research Database (Denmark)

    Bruun, Jesper; Evans, Robert Harry

    2014-01-01

    This paper describes the background for, realisation of and author reflections on a network workshop held at ESERA2013. As a new research area in science education, networks offer a unique opportunity to visualise and find patterns and relationships in complicated social or academic network data....... These include student relations and interactions and epistemic and linguistic networks of words, concepts and actions. Network methodology has already found use in science education research. However, while networks hold the potential for new insights, they have not yet found wide use in the science education...... research community. With this workshop, participants were offered a way into network science based on authentic educational research data. The workshop was constructed as an inquiry lesson with emphasis on user autonomy. Learning activities had participants choose to work with one of two cases of networks...

  14. Network Convergence

    Indian Academy of Sciences (India)

    First page Back Continue Last page Overview Graphics. Network Convergence. User is interested in application and content - not technical means of distribution. Boundaries between distribution channels fade out. Network convergence leads to seamless application and content solutions.

  15. Industrial Networks

    DEFF Research Database (Denmark)

    Karlsson, Christer

    2015-01-01

    Companies organize in a way that involves many activities that are external to the traditional organizational boundaries. This presents challenges to operations management and managing operations involves many issues and actions dealing with external networks. Taking a network perspective changes...

  16. Network Science

    National Research Council Canada - National Science Library

    Leland, Will

    2006-01-01

    OVERVIEW: (1) A committee of technical experts, military officers and R&D managers was assembled by the National Research Council to reach consensus on the nature of networks and network research. (2...

  17. Markets on Networks

    Science.gov (United States)

    Toroczkai, Zoltan; Anghel, Marian; Bassler, Kevin; Korniss, Gyorgy

    2003-03-01

    The dynamics of human, and most biological populations is characterized by competition for resources. By its own nature, this dynamics creates the group of "elites", formed by those agents who have strategies that are the most successful in the given situation, and therefore the rest of the agents will tend to follow, imitate, or interact with them, creating a social structure of leadership in the agent society. These inter-agent communications generate a complex social network with small-world character which itself forms the substrate for a second network, the action network. The latter is a highly dynamic, adaptive, directed network, defined by those inter-agent communication links on the substrate along which the passed information /prediction is acted upon by the other agents. By using the minority game for competition dynamics, here we show that when the substrate network is highly connected, the action network spontaneously develops hubs with a broad distribution of out-degrees, defining a robust leadership structure that is scale-free. Furthermore, in certain, realistic parameter ranges, facilitated by information passing on the action network, agents can spontaneously generate a high degree of cooperation making the collective almost maximally efficient.

  18. Network Coded Software Defined Networking

    DEFF Research Database (Denmark)

    Krigslund, Jeppe; Hansen, Jonas; Roetter, Daniel Enrique Lucani

    2015-01-01

    Software Defined Networking (SDN) and Network Coding (NC) are two key concepts in networking that have garnered a large attention in recent years. On the one hand, SDN's potential to virtualize services in the Internet allows a large flexibility not only for routing data, but also to manage....... This paper advocates for the use of SDN to bring about future Internet and 5G network services by incorporating network coding (NC) functionalities. The inherent flexibility of both SDN and NC provides a fertile ground to envision more efficient, robust, and secure networking designs, that may also...

  19. Network Simulation

    CERN Document Server

    Fujimoto, Richard

    2006-01-01

    "Network Simulation" presents a detailed introduction to the design, implementation, and use of network simulation tools. Discussion topics include the requirements and issues faced for simulator design and use in wired networks, wireless networks, distributed simulation environments, and fluid model abstractions. Several existing simulations are given as examples, with details regarding design decisions and why those decisions were made. Issues regarding performance and scalability are discussed in detail, describing how one can utilize distributed simulation methods to increase the

  20. Neural Networks and Genetic Algorithms Applied for Implementing the Management Model “Triple A” in a Supply Chain. Case: Collection Centers of Raw Milk in the Azuay Province

    Directory of Open Access Journals (Sweden)

    Juan Pablo Bermeo M.

    2016-01-01

    Full Text Available To get successful the companies need a combination of several factors, the most important one is the management of Supply Chain. This paper proposes the use of intelligent systems such as Artificial Neural Networks (ANN and Genetic Algorithms as support systems together with monitoring indicators and monitoring, in order to implement the management model Triple A, which is focused on Agility-Adaptability-Alignment, where the “Agility” is the speed of response to changes in demand, “Adaptability” is the ability to tailor the supply chain front market fluctuations and "Alignment" is to align the chain between consumers and suppliers. The Neural Network was trained to work as a predictor of demand and will improve the “agility” of the supply chain, the genetic algorithm is used to obtain optimal routes of pickup from providers, this support to the “alignment” the product of suppliers in the supply chain to final customers; the Neural Network with the Genetic Algorithm together serve as support to “adapt” the supply chain to variations of demand and the suppliers, however, for successful of the model are need other factors such as the use of indicators and training of staff on the administration of management model triple A in the supply chain.

  1. Networking of safeguards systems

    International Nuclear Information System (INIS)

    Chare, P.; Dutrannois, A.; Kloeckner, W.; Swinhoe, M.

    1995-01-01

    This paper discusses the design of a safeguards system that can be incorporated into a plant during the final phase of its construction to permit the acquisition and transmission of data during plant operation in the absence of an inspector. The system is an example of a networked data system of weighing, identity, and NDA information. It collects all of its non-surveillance data produced by safeguards equipment in a fuel fabrication plant. The data collection and transfer tasks are carried out by two software packages: NEGUS, a redundant data acquisition system designed to record neutron coincidence data, high-resolution gamma spectra, and sensor data for the NDA information and associated barcode identity information, and BRANCH, which deals with weighing and associated identity information. These processes collect data from local electronics using an ethernet network and provide information to the main review program

  2. Workforce Competitiveness Collection. "LINCS" Resource Collection News

    Science.gov (United States)

    Literacy Information and Communication System, 2011

    2011-01-01

    This edition of "'LINCS' Resource Collection News" features the Workforce Competitiveness Collection, covering the topics of workforce education, English language acquisition, and technology. Each month Collections News features one of the three "LINCS" (Literacy Information and Communication System) Resource Collections--Basic…

  3. 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.

  4. On the Design of Energy Efficient Optical Networks with Software Defined Networking Control Across Core and Access Networks

    DEFF Research Database (Denmark)

    Wang, Jiayuan; Yan, Ying; Dittmann, Lars

    2013-01-01

    This paper presents a Software Defined Networking (SDN) control plane based on an overlay GMPLS control model. The SDN control platform manages optical core networks (WDM/DWDM networks) and the associated access networks (GPON networks), which makes it possible to gather global information...... and enable wider areas' energy efficiency networking. The energy related information of the networks and the types of the traffic flows are collected and utilized for the end-to-end QoS provision. Dynamic network simulation results show that by applying different routing algorithms according to the type...... of traffic in the core networks, the energy efficiency of the network is improved without compromising the quality of service....

  5. Simulating synchronization in neuronal networks

    Science.gov (United States)

    Fink, Christian G.

    2016-06-01

    We discuss several techniques used in simulating neuronal networks by exploring how a network's connectivity structure affects its propensity for synchronous spiking. Network connectivity is generated using the Watts-Strogatz small-world algorithm, and two key measures of network structure are described. These measures quantify structural characteristics that influence collective neuronal spiking, which is simulated using the leaky integrate-and-fire model. Simulations show that adding a small number of random connections to an otherwise lattice-like connectivity structure leads to a dramatic increase in neuronal synchronization.

  6. Technical Network

    CERN Multimedia

    2007-01-01

    In order to optimise the management of the Technical Network (TN), to facilitate understanding of the purpose of devices connected to the TN and to improve security incident handling, the Technical Network Administrators and the CNIC WG have asked IT/CS to verify the "description" and "tag" fields of devices connected to the TN. Therefore, persons responsible for systems connected to the TN will receive e-mails from IT/CS asking them to add the corresponding information in the network database at "network-cern-ch". Thank you very much for your cooperation. The Technical Network Administrators & the CNIC WG

  7. Spatial networks

    Science.gov (United States)

    Barthélemy, Marc

    2011-02-01

    Complex systems are very often organized under the form of networks where nodes and edges are embedded in space. Transportation and mobility networks, Internet, mobile phone networks, power grids, social and contact networks, and neural networks, are all examples where space is relevant and where topology alone does not contain all the information. Characterizing and understanding the structure and the evolution of spatial networks is thus crucial for many different fields, ranging from urbanism to epidemiology. An important consequence of space on networks is that there is a cost associated with the length of edges which in turn has dramatic effects on the topological structure of these networks. We will thoroughly explain the current state of our understanding of how the spatial constraints affect the structure and properties of these networks. We will review the most recent empirical observations and the most important models of spatial networks. We will also discuss various processes which take place on these spatial networks, such as phase transitions, random walks, synchronization, navigation, resilience, and disease spread.

  8. Network science

    CERN Document Server

    Barabasi, Albert-Laszlo

    2016-01-01

    Networks are everywhere, from the Internet, to social networks, and the genetic networks that determine our biological existence. Illustrated throughout in full colour, this pioneering textbook, spanning a wide range of topics from physics to computer science, engineering, economics and the social sciences, introduces network science to an interdisciplinary audience. From the origins of the six degrees of separation to explaining why networks are robust to random failures, the author explores how viruses like Ebola and H1N1 spread, and why it is that our friends have more friends than we do. Using numerous real-world examples, this innovatively designed text includes clear delineation between undergraduate and graduate level material. The mathematical formulas and derivations are included within Advanced Topics sections, enabling use at a range of levels. Extensive online resources, including films and software for network analysis, make this a multifaceted companion for anyone with an interest in network sci...

  9. Vulnerability of network of networks

    Science.gov (United States)

    Havlin, S.; Kenett, D. Y.; Bashan, A.; Gao, J.; Stanley, H. E.

    2014-10-01

    Our dependence on networks - be they infrastructure, economic, social or others - leaves us prone to crises caused by the vulnerabilities of these networks. There is a great need to develop new methods to protect infrastructure networks and prevent cascade of failures (especially in cases of coupled networks). Terrorist attacks on transportation networks have traumatized modern societies. With a single blast, it has become possible to paralyze airline traffic, electric power supply, ground transportation or Internet communication. How, and at which cost can one restructure the network such that it will become more robust against malicious attacks? The gradual increase in attacks on the networks society depends on - Internet, mobile phone, transportation, air travel, banking, etc. - emphasize the need to develop new strategies to protect and defend these crucial networks of communication and infrastructure networks. One example is the threat of liquid explosives a few years ago, which completely shut down air travel for days, and has created extreme changes in regulations. Such threats and dangers warrant the need for new tools and strategies to defend critical infrastructure. In this paper we review recent advances in the theoretical understanding of the vulnerabilities of interdependent networks with and without spatial embedding, attack strategies and their affect on such networks of networks as well as recently developed strategies to optimize and repair failures caused by such attacks.

  10. Optical Access Networks

    Science.gov (United States)

    Zheng, Jun; Ansari, Nirwan

    2005-01-01

    have been receiving tremendous attention from both academia and industry. A large number of research activities have been carried out or are now underway this hot area. The purpose of this feature issue is to expose the networking community to the latest research breakthroughs and progresses in the area of optical access networks. Scope of Contributions This feature issue aims to present a collection of papers that focus on the state-of-the-art research in various networking aspects of optical access networks. Original papers are solicited from all researchers involved in area of optical access networks. Topics of interest include but not limited to: Optical access network architectures and protocols Passive optical networks (BPON, EPON, GPON, etc.) Active optical networks Multiple access control Multiservices and QoS provisioning Network survivability Field trials and standards Performance modeling and analysis Manuscript Submission To submit to this special issue, follow the normal procedure for submission to JON, indicating ``Optical Access Networks feature' in the ``Comments' field of the online submission form. For all other questions relating to this feature issue, please send an e-mail to jon@osa.org, subject line ``Optical Access Networks' Additional information can be found on the JON website: http://www.osa-jon.org/submission/. Submission Deadline: 1 June 2005

  11. Environmental monitoring network for India

    Science.gov (United States)

    P.V. Sundareshwar; R. Murtugudde; G. Srinivasan; S. Singh; K.J. Ramesh; R. Ramesh; S.B. Verma; D. Agarwal; D. Baldocchi; C.K. Baru; K.K. Baruah; G.R. Chowdhury; V.K. Dadhwal; C.B.S. Dutt; J. Fuentes; Prabhat Gupta; W.W. Hardgrove; M. Howard; C.S. Jha; S. Lal; W.K. Michener; A.P. Mitra; J.T. Morris; R.R. Myneni; M. Naja; R. Nemani; R. Purvaja; S. Raha; S.K. Santhana Vanan; M. Sharma; A. Subramaniam; R. Sukumar; R.R. Twilley; P.R. Zimmerman

    2007-01-01

    Understanding the consequences of global environmental change and its mitigation will require an integrated global effort of comprehensive long-term data collection, synthesis, and action (1). The last decade has seen a dramatic global increase in the number of networked monitoring sites. For example, FLUXNET is a global collection of >300 micrometeorological...

  12. Organising collective reputation: An Ostromian perspective

    Directory of Open Access Journals (Sweden)

    Boldizsár Megyesi

    2016-09-01

    Full Text Available What do collective reputation and communal pastures have in common? Collective reputation is an important type of collective good produced by many business networks. We argue that it has the structure of a common-pool resource, which points to the relevance of Elinor Ostrom’s theory about the community governance of natural common-pool resources. After adapting the Ostromian framework to the phenomenon of collective reputation, we explore the experience of two groups of winemaking enterprises in Hungary who set up systems of quality assurance in order to protect and improve their joint reputation. We examine if the conditions identified by Ostrom as favourable for the self-governance of commons are also conducive to the governance of collective reputation. Our findings validate our conjecture that research on goal-oriented business networks may use insights from the mature theory of ‘governing the commons’. Potential pathways for further research are outlined.

  13. Twisted network programming essentials

    CERN Document Server

    Fettig, Abe

    2005-01-01

    Twisted Network Programming Essentials from O'Reilly is a task-oriented look at this new open source, Python-based technology. The book begins with recommendations for various plug-ins and add-ons to enhance the basic package as installed. It then details Twisted's collection simple network protocols, and helper utilities. The book also includes projects that let you try out the Twisted framework for yourself. For example, you'll find examples of using Twisted to build web services applications using the REST architecture, using XML-RPC, and using SOAP. Written for developers who want to s

  14. Network Coded Software Defined Networking

    DEFF Research Database (Denmark)

    Hansen, Jonas; Roetter, Daniel Enrique Lucani; Krigslund, Jeppe

    2015-01-01

    Software defined networking has garnered large attention due to its potential to virtualize services in the Internet, introducing flexibility in the buffering, scheduling, processing, and routing of data in network routers. SDN breaks the deadlock that has kept Internet network protocols stagnant...... for decades, while applications and physical links have evolved. This article advocates for the use of SDN to bring about 5G network services by incorporating network coding (NC) functionalities. The latter constitutes a major leap forward compared to the state-of-the- art store and forward Internet paradigm...

  15. 76 FR 62756 - Agency Information Collection Activities: Proposed Collection; Comment Request-People's Garden...

    Science.gov (United States)

    2011-10-11

    ...: Proposed Collection; Comment Request--People's Garden Initiative Evaluation of Healthy Gardens Healthy... on proposed information collections. This is a new information for the ``Healthy Gardens, Healthy Youth Study,'' part of the USDA's People's Garden program. This study will use the network of...

  16. 78 FR 54660 - Agency Information Collection Activities; Proposed Collection; Public Comment Request

    Science.gov (United States)

    2013-09-05

    ... efficiency; and improve patient outcomes. In each of these categories, specific indicators were designed to be reported through a performance monitoring Web site. Likely Respondents: Telehealth Network... quality, utility, and clarity of the information to be collected, and (4) the use of automated collection...

  17. Efficient Networks Communication Routing Using Swarm Intelligence

    OpenAIRE

    Koushal Kumar

    2012-01-01

    As demonstrated by natural biological swarm’s collective intelligence has an abundance of desirable properties for problem-solving like in network routing. The focus of this paper is in the applications of swarm based intelligence in information routing for communication networks. As we know networks are growing and adopting new platforms as new technologies comes. Also according to new demands and requirements networks topologies and its complexity is increasing with time. Thus it is becomin...

  18. Associative memory in phasing neuron networks

    Energy Technology Data Exchange (ETDEWEB)

    Nair, Niketh S [ORNL; Bochove, Erik J. [United States Air Force Research Laboratory, Kirtland Air Force Base; Braiman, Yehuda [ORNL

    2014-01-01

    We studied pattern formation in a network of coupled Hindmarsh-Rose model neurons and introduced a new model for associative memory retrieval using networks of Kuramoto oscillators. Hindmarsh-Rose Neural Networks can exhibit a rich set of collective dynamics that can be controlled by their connectivity. Specifically, we showed an instance of Hebb's rule where spiking was correlated with network topology. Based on this, we presented a simple model of associative memory in coupled phase oscillators.

  19. Composite Social Network for Predicting Mobile Apps Installation

    Science.gov (United States)

    2011-06-02

    Social network tools (such as the Facebook app and the Twitter app) can observe users’ online friendship network . In this work, our key idea is...the friendship network from phones by collecting data from social networking apps such as the Facebook and Twitter apps. We summarize all the networks ...ar X iv :1 10 6. 03 59 v1 [ cs .S I] 2 J un 2 01 1 Composite Social Network for Predicting Mobile Apps Installation Wei Pan

  20. Network Science Center Research Team’s Visit to Kampala, Uganda

    Science.gov (United States)

    2013-04-15

    TERMS Network Analysis, Economic Networks, Entrepreneurial Ecosystems , Economic Development, Data Collection 16. SECURITY CLASSIFICATION OF: 17...the Project Synopsis, Developing Network Models of Entrepreneurial Ecosystems in Developing Economies, on the Network Science Center web site.) A...Thomas visited Kampala, Uganda in support of an ongoing Network Science Center project to develop models of entrepreneurial networks. Our Center has

  1. Peripheral blood collection

    DEFF Research Database (Denmark)

    Franken, Carmen; Remy, Sylvie; Lambrechts, Nathalie

    2016-01-01

    A crucial challenge for gene expression analysis in human biomonitoring studies on whole blood samples is rapid sample handling and mRNA stabilization. This study was designed to evaluate the impact of short bench times (less than 30 min) on yield, quality and gene expression of mRNA in the prese......A crucial challenge for gene expression analysis in human biomonitoring studies on whole blood samples is rapid sample handling and mRNA stabilization. This study was designed to evaluate the impact of short bench times (less than 30 min) on yield, quality and gene expression of m......RNA in the presence of different stabilization buffers (TempusTM Blood RNA tube and RNAlater® Stabilization Reagent). Microarray analyzes showed significant changes over short periods of time in expression of a considerate part of the transcriptome (2356 genes) with a prominent role for NFкB-, cancer......- and glucocorticoid-mediated networks, and specifically interleukin-8 (IL-8). These findings suggest that even short bench times affect gene expression, requiring to carry out blood collection in a strictly standardized way. © 2016 Informa UK Limited, trading as Taylor & Francis Group....

  2. Networked Identities

    DEFF Research Database (Denmark)

    Ryberg, Thomas; Larsen, Malene Charlotte

    2008-01-01

    of CoPs we shall argue that the metaphor or theory of networked learning is itself confronted with some central tensions and challenges that need to be addressed. We then explore these theoretical and analytic challenges to the network metaphor, through an analysis of a Danish social networking site. We......In this article we take up a critique of the concept of Communities of Practice (CoP) voiced by several authors, who suggest that networks may provide a better metaphor to understand social forms of organisation and learning. Through a discussion of the notion of networked learning and the critique...... argue that understanding meaning-making and ‘networked identities’ may be relevant analytic entry points in navigating the challenges....

  3. The Network Completion Problem: Inferring Missing Nodes and Edges in Networks

    Energy Technology Data Exchange (ETDEWEB)

    Kim, M; Leskovec, J

    2011-11-14

    Network structures, such as social networks, web graphs and networks from systems biology, play important roles in many areas of science and our everyday lives. In order to study the networks one needs to first collect reliable large scale network data. While the social and information networks have become ubiquitous, the challenge of collecting complete network data still persists. Many times the collected network data is incomplete with nodes and edges missing. Commonly, only a part of the network can be observed and we would like to infer the unobserved part of the network. We address this issue by studying the Network Completion Problem: Given a network with missing nodes and edges, can we complete the missing part? We cast the problem in the Expectation Maximization (EM) framework where we use the observed part of the network to fit a model of network structure, and then we estimate the missing part of the network using the model, re-estimate the parameters and so on. We combine the EM with the Kronecker graphs model and design a scalable Metropolized Gibbs sampling approach that allows for the estimation of the model parameters as well as the inference about missing nodes and edges of the network. Experiments on synthetic and several real-world networks show that our approach can effectively recover the network even when about half of the nodes in the network are missing. Our algorithm outperforms not only classical link-prediction approaches but also the state of the art Stochastic block modeling approach. Furthermore, our algorithm easily scales to networks with tens of thousands of nodes.

  4. Network security

    CERN Document Server

    Perez, André

    2014-01-01

    This book introduces the security mechanisms deployed in Ethernet, Wireless-Fidelity (Wi-Fi), Internet Protocol (IP) and MultiProtocol Label Switching (MPLS) networks. These mechanisms are grouped throughout the book according to the following four functions: data protection, access control, network isolation, and data monitoring. Data protection is supplied by data confidentiality and integrity control services. Access control is provided by a third-party authentication service. Network isolation is supplied by the Virtual Private Network (VPN) service. Data monitoring consists of applying

  5. Network cohesion

    OpenAIRE

    Cavalcanti, Tiago V. V.; Giannitsarou, Chryssi; Johnson, Charles R.

    2016-01-01

    This is the final version of the article. It first appeared from Springer via http://dx.doi.org/10.1007/s00199-016-0992-1 We define a measure of network cohesion and show how it arises naturally in a broad class of dynamic models of endogenous perpetual growth with network externalities. Via a standard growth model, we show why network cohesion is crucial for conditional convergence and explain that as cohesion increases, convergence is faster. We prove properties of network cohesion and d...

  6. Technical Network

    CERN Multimedia

    2007-01-01

    In order to optimize the management of the Technical Network (TN), to ease the understanding and purpose of devices connected to the TN, and to improve security incident handling, the Technical Network Administrators and the CNIC WG have asked IT/CS to verify the "description" and "tag" fields of devices connected to the TN. Therefore, persons responsible for systems connected to the TN will receive email notifications from IT/CS asking them to add the corresponding information in the network database. Thank you very much for your cooperation. The Technical Network Administrators & the CNIC WG

  7. Computer Networks and Globalization

    Directory of Open Access Journals (Sweden)

    J. Magliaro

    2007-07-01

    Full Text Available Communication and information computer networks connect the world in ways that make globalization more natural and inequity more subtle. As educators, we look at these phenomena holistically analyzing them from the realist’s view, thus exploring tensions, (in equity and (injustice, and from the idealist’s view, thus embracing connectivity, convergence and development of a collective consciousness. In an increasingly market- driven world we find examples of openness and human generosity that are based on networks, specifically the Internet. After addressing open movements in publishing, software industry and education, we describe the possibility of a dialectic equilibrium between globalization and indigenousness in view of ecologically designed future smart networks

  8. Crawling Facebook for Social Network Analysis Purposes

    OpenAIRE

    Catanese, Salvatore A.; De Meo, Pasquale; Ferrara, Emilio; Fiumara, Giacomo; Provetti, Alessandro

    2011-01-01

    We describe our work in the collection and analysis of massive data describing the connections between participants to online social networks. Alternative approaches to social network data collection are defined and evaluated in practice, against the popular Facebook Web site. Thanks to our ad-hoc, privacy-compliant crawlers, two large samples, comprising millions of connections, have been collected; the data is anonymous and organized as an undirected graph. We describe a set of tools that w...

  9. Weighted Networks at the Polish Market

    Science.gov (United States)

    Chmiel, A. M.; Sienkiewicz, J.; Suchecki, K.; Hołyst, J. A.

    During the last few years various models of networks [1,2] have become a powerful tool for analysis of complex systems in such distant fields as Internet [3], biology [4], social groups [5], ecology [6] and public transport [7]. Modeling behavior of economical agents is a challenging issue that has also been studied from a network point of view. The examples of such studies are models of financial networks [8], supply chains [9, 10], production networks [11], investment networks [12] or collective bank bankrupcies [13, 14]. Relations between different companies have been already analyzed using several methods: as networks of shareholders [15], networks of correlations between stock prices [16] or networks of board directors [17]. In several cases scaling laws for network characteristics have been observed.

  10. An Application of Social Network Analysis on Military Strategy, System Networks and the Phases of War

    Science.gov (United States)

    2015-03-26

    power grid network also used by Watts and Strogatz [53]. A summary of all exemplar networks is located in Table 9 below: Table 9: Full Exemplar...53] D. J. Watts and S. H. Strogatz , “Collective Dynamics of “Small World” networks,” Nature, no. 393, pp. 440-442, 1998. [54] M. E. Porter

  11. New challenges in computational collective intelligence

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen, Ngoc Thanh; Katarzyniak, Radoslaw Piotr [Wroclaw Univ. of Technology (Poland). Inst. of Informatics; Janiak, Adam (eds.) [Wroclaw Univ. of Technology (Poland). Inst. of Computer Engineering, Control and Robotics

    2009-07-01

    The book consists of 29 chapters which have been selected and invited from the submissions to the 1{sup st} International Conference on Collective Intelligence - Semantic Web, Social Networks and Multiagent Systems (ICCCI 2009). All chapters in the book discuss various examples of applications of computational collective intelligence and related technologies to such fields as semantic web, information systems ontologies, social networks, agent and multiagent systems. The editors hope that the book can be useful for graduate and Ph.D. students in Computer Science, in particular participants to courses on Soft Computing, Multi-Agent Systems and Robotics. This book can also be useful for researchers working on the concept of computational collective intelligence in artificial populations. It is the hope of the editors that readers of this volume can find many inspiring ideas and use them to create new cases intelligent collectives. Many such challenges are suggested by particular approaches and models presented in particular chapters of this book. (orig.)

  12. The Colombia Seismological Network

    Science.gov (United States)

    Blanco Chia, J. F.; Poveda, E.; Pedraza, P.

    2013-05-01

    The latest seismological equipment and data processing instrumentation installed at the Colombia Seismological Network (RSNC) are described. System configuration, network operation, and data management are discussed. The data quality and the new seismological products are analyzed. The main purpose of the network is to monitor local seismicity with a special emphasis on seismic activity surrounding the Colombian Pacific and Caribbean oceans, for early warning in case a Tsunami is produced by an earthquake. The Colombian territory is located at the South America northwestern corner, here three tectonic plates converge: Nazca, Caribbean and the South American. The dynamics of these plates, when resulting in earthquakes, is continuously monitored by the network. In 2012, the RSNC registered in 2012 an average of 67 events per day; from this number, a mean of 36 earthquakes were possible to be located well. In 2010 the network was also able to register an average of 67 events, but it was only possible to locate a mean of 28 earthquakes daily. This difference is due to the expansion of the network. The network is made up of 84 stations equipped with different kind of broadband 40s, 120s seismometers, accelerometers and short period 1s sensors. The signal is transmitted continuously in real-time to the Central Recording Center located at Bogotá, using satellite, telemetry, and Internet. Moreover, there are some other stations which are required to collect the information in situ. Data is recorded and processed digitally using two different systems, EARTHWORM and SEISAN, which are able to process and share the information between them. The RSNC has designed and implemented a web system to share the seismological data. This innovative system uses tools like Java Script, Oracle and programming languages like PHP to allow the users to access the seismicity registered by the network almost in real time as well as to download the waveform and technical details. The coverage

  13. Overlay networks toward information networking

    CERN Document Server

    Tarkoma, Sasu

    2010-01-01

    With their ability to solve problems in massive information distribution and processing, while keeping scaling costs low, overlay systems represent a rapidly growing area of R&D with important implications for the evolution of Internet architecture. Inspired by the author's articles on content based routing, Overlay Networks: Toward Information Networking provides a complete introduction to overlay networks. Examining what they are and what kind of structures they require, the text covers the key structures, protocols, and algorithms used in overlay networks. It reviews the current state of th

  14. Evaluated data collections from ENSDF

    International Nuclear Information System (INIS)

    Ewbank, W.B.

    1979-01-01

    For several years the Nuclear Data Project has been maintaining an Evaluated Nuclear Structure Data File (ENSDF), which is designed to include critically evaluated values for most nuclear spectroscopic quantities. The information in ENSDF is the same as in the Nuclear Data Sheets, which illustrates two particular output formats (drawings and tables). Spectroscopic information for nuclei with A < 45 is put into ENSDF from the evaluations of Aizenberg-Selove and of Endt and van der Leun. An international network was organized to provide regular revisions of the data file. Computer facilities were developed to retrieve collections of evaluated data for special calculations or detailed examination

  15. Probabilistic Networks

    DEFF Research Database (Denmark)

    Jensen, Finn Verner; Lauritzen, Steffen Lilholt

    2001-01-01

    This article describes the basic ideas and algorithms behind specification and inference in probabilistic networks based on directed acyclic graphs, undirected graphs, and chain graphs.......This article describes the basic ideas and algorithms behind specification and inference in probabilistic networks based on directed acyclic graphs, undirected graphs, and chain graphs....

  16. 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

  17. Temporal networks

    Science.gov (United States)

    Holme, Petter; Saramäki, Jari

    2012-10-01

    A great variety of systems in nature, society and technology-from the web of sexual contacts to the Internet, from the nervous system to power grids-can be modeled as graphs of vertices coupled by edges. The network structure, describing how the graph is wired, helps us understand, predict and optimize the behavior of dynamical systems. In many cases, however, the edges are not continuously active. As an example, in networks of communication via e-mail, text messages, or phone calls, edges represent sequences of instantaneous or practically instantaneous contacts. In some cases, edges are active for non-negligible periods of time: e.g., the proximity patterns of inpatients at hospitals can be represented by a graph where an edge between two individuals is on throughout the time they are at the same ward. Like network topology, the temporal structure of edge activations can affect dynamics of systems interacting through the network, from disease contagion on the network of patients to information diffusion over an e-mail network. In this review, we present the emergent field of temporal networks, and discuss methods for analyzing topological and temporal structure and models for elucidating their relation to the behavior of dynamical systems. In the light of traditional network theory, one can see this framework as moving the information of when things happen from the dynamical system on the network, to the network itself. Since fundamental properties, such as the transitivity of edges, do not necessarily hold in temporal networks, many of these methods need to be quite different from those for static networks. The study of temporal networks is very interdisciplinary in nature. Reflecting this, even the object of study has many names-temporal graphs, evolving graphs, time-varying graphs, time-aggregated graphs, time-stamped graphs, dynamic networks, dynamic graphs, dynamical graphs, and so on. This review covers different fields where temporal graphs are considered

  18. Network Affordances

    DEFF Research Database (Denmark)

    Samson, Audrey; Soon, Winnie

    2015-01-01

    This paper examines the notion of network affordance within the context of network art. Building on Gibson's theory (Gibson, 1979) we understand affordance as the perceived and actual parameters of a thing. We expand on Gaver's affordance of predictability (Gaver, 1996) to include ecological...... and computational parameters of unpredictability. We illustrate the notion of unpredictability by considering four specific works that were included in a network art exhibiton, SPEED SHOW [2.0] Hong Kong. The paper discusses how the artworks are contingent upon the parameteric relations (Parisi, 2013......), of the network. We introduce network affordance as a dynamic framework that could articulate the experienced tension arising from the (visible) symbolic representation of computational processes and its hidden occurrences. We base our proposal on the experience of both organising the SPEED SHOW and participating...

  19. Network chemistry, network toxicology, network informatics, and network behavioristics: A scientific outline

    OpenAIRE

    WenJun Zhang

    2016-01-01

    In present study, I proposed some new sciences: network chemistry, network toxicology, network informatics, and network behavioristics. The aims, scope and scientific foundation of these sciences are outlined.

  20. Study of Tools for Network Discovery and Network Mapping

    Science.gov (United States)

    2003-11-01

    connected to the switch. iv. Accessibility of historical data and event data In general, network discovery tools keep a history of the collected...has the following software dependencies: - Java Virtual machine 76 - Perl modules - RRD Tool - TomCat - PostgreSQL STRENGTHS AND...systems - provide a simple view of the current network status - generate alarms on status change - generate history of status change VISUAL MAP

  1. Network analysis applications in hydrology

    Science.gov (United States)

    Price, Katie

    2017-04-01

    Applied network theory has seen pronounced expansion in recent years, in fields such as epidemiology, computer science, and sociology. Concurrent development of analytical methods and frameworks has increased possibilities and tools available to researchers seeking to apply network theory to a variety of problems. While water and nutrient fluxes through stream systems clearly demonstrate a directional network structure, the hydrological applications of network theory remain under­explored. This presentation covers a review of network applications in hydrology, followed by an overview of promising network analytical tools that potentially offer new insights into conceptual modeling of hydrologic systems, identifying behavioral transition zones in stream networks and thresholds of dynamical system response. Network applications were tested along an urbanization gradient in Atlanta, Georgia, USA. Peachtree Creek and Proctor Creek. Peachtree Creek contains a nest of five long­term USGS streamflow and water quality gages, allowing network application of long­term flow statistics. The watershed spans a range of suburban and heavily urbanized conditions. Summary flow statistics and water quality metrics were analyzed using a suite of network analysis techniques, to test the conceptual modeling and predictive potential of the methodologies. Storm events and low flow dynamics during Summer 2016 were analyzed using multiple network approaches, with an emphasis on tomogravity methods. Results indicate that network theory approaches offer novel perspectives for understanding long­ term and event­based hydrological data. Key future directions for network applications include 1) optimizing data collection, 2) identifying "hotspots" of contaminant and overland flow influx to stream systems, 3) defining process domains, and 4) analyzing dynamic connectivity of various system components, including groundwater­surface water interactions.

  2. 4th International Conference in Network Analysis

    CERN Document Server

    Koldanov, Petr; Pardalos, Panos

    2016-01-01

    The contributions in this volume cover a broad range of topics including maximum cliques, graph coloring, data mining, brain networks, Steiner forest, logistic and supply chain networks. Network algorithms and their applications to market graphs, manufacturing problems, internet networks and social networks are highlighted. The "Fourth International Conference in Network Analysis," held at the Higher School of Economics, Nizhny Novgorod in May 2014, initiated joint research between scientists, engineers and researchers from academia, industry and government; the major results of conference participants have been reviewed and collected in this Work. Researchers and students in mathematics, economics, statistics, computer science and engineering will find this collection a valuable resource filled with the latest research in network analysis.

  3. Privacy-Preserving Trajectory Collection

    DEFF Research Database (Denmark)

    Gidofalvi, Gyozo; Xuegang, Huang; Pedersen, Torben Bach

    2008-01-01

    In order to provide context--aware Location--Based Services, real location data of mobile users must be collected and analyzed by spatio--temporal data mining methods. However, the data mining methods need precise location data, while the mobile users want to protect their location privacy....... To remedy this situation, this paper first formally defines novel location privacy requirements. Then, it briefly presents a system for privacy--preserving trajectory collection that meets these requirements. The system is composed of an untrusted server and clients communicating in a P2P network. Location...... data is anonymized in the system using data cloaking and data swapping techniques. Finally, the paper empirically demonstrates that the proposed system is effective and feasible....

  4. Advances in Collective Intelligence 2011

    CERN Document Server

    Baumöl, Ulrike; Krämer, Bernd

    2012-01-01

    Collective intelligence has become an attractive subject of interest for both academia and industry. More and more conferences and workshops discuss the impact of the users‘ motivation to participate in the value creation process, the enabling role of leading-edge information and communication technologies and the need for better algorithms to deal with the growing amount of shared data. There are many interesting and challenging topics that need to be researched and discussed with respect to knowledge creation, creativity and innovation processes carried forward in the emerging communities of practice. COLLIN is on the path to become the flagship conference in the areas of collective intelligence and ICT-enabled social networking. We were delighted to again receive contributions from different parts of the world including Australia, Europe, Asia, and the United States. Encouraged by the positive response, we plan COLLIN 2012 to be held next year end of August at FernUniverstität in Hagen. In order to guar...

  5. Mobile infostation network technology

    Science.gov (United States)

    Rajappan, Gowri; Acharya, Joydeep; Liu, Hongbo; Mandayam, Narayan; Seskar, Ivan; Yates, Roy

    2006-05-01

    Inefficient use of network resources on the battlefield is a serious liability: if an asset communicates with the network command for data-a terrain map, for instance-it ties up the end-to-end network resources. When many such assets contend for data simultaneously, traffic is limited by the slowest link along the path from the network command to the asset. A better approach is for a local server, known as an infostation, to download data on an anticipated-need basis when the network load is low. The infostation can then dump data when needed to the assets over a high-speed wireless connection. The infostation serves the local assets over an OFDM-based wireless data link that has MIMO enhancements for high data rate and robustness. We aim for data rate in excess of 100 Mbps, spectral efficiency in excess of 5 bits/sec/Hz, and robustness to poor channel conditions and jammers. We propose an adaptive physical layer that determines power levels, modulation schemes, and the MIMO enhancements to use based on the channel state and the level of interference in the system. We also incorporate the idea of superuser: a user who is allowed preferential use of the high data rate link. We propose a MAC that allows for this priority-based bandwidth allocation scheme. The proposed infostation MAC is integrated tightly with the physical layer through a cross-layer design. We call the proposed infostation PHY, MAC, and network technology, collectively, as the Mobile Infostation Network Technology (MINT).

  6. Research@ARL: Network Sciences

    Science.gov (United States)

    2013-03-01

    function in concert. Consider the behavior of social insects, such as bees and ants. Fish and birds are other examples of animals whose collective...Tropical Watershed, Springer/Kluwer, 83–95, 2005. Lehner, B. and Döll, P.: Development and validation of a global database of lakes, reservoirs and wetlands ...what it would be in an unperturbed network. A biological network with this sensitivity to error would not survive for very long in the wild . For

  7. Operating systems and network protocols for wireless sensor networks.

    Science.gov (United States)

    Dutta, Prabal; Dunkels, Adam

    2012-01-13

    Sensor network protocols exist to satisfy the communication needs of diverse applications, including data collection, event detection, target tracking and control. Network protocols to enable these services are constrained by the extreme resource scarcity of sensor nodes-including energy, computing, communications and storage-which must be carefully managed and multiplexed by the operating system. These challenges have led to new protocols and operating systems that are efficient in their energy consumption, careful in their computational needs and miserly in their memory footprints, all while discovering neighbours, forming networks, delivering data and correcting failures.

  8. Accelerating networks

    International Nuclear Information System (INIS)

    Smith, David M D; Onnela, Jukka-Pekka; Johnson, Neil F

    2007-01-01

    Evolving out-of-equilibrium networks have been under intense scrutiny recently. In many real-world settings the number of links added per new node is not constant but depends on the time at which the node is introduced in the system. This simple idea gives rise to the concept of accelerating networks, for which we review an existing definition and-after finding it somewhat constrictive-offer a new definition. The new definition provided here views network acceleration as a time dependent property of a given system as opposed to being a property of the specific algorithm applied to grow the network. The definition also covers both unweighted and weighted networks. As time-stamped network data becomes increasingly available, the proposed measures may be easily applied to such empirical datasets. As a simple case study we apply the concepts to study the evolution of three different instances of Wikipedia, namely, those in English, German, and Japanese, and find that the networks undergo different acceleration regimes in their evolution

  9. A Smart Home Gateway Platform for Data Collection and Awareness

    OpenAIRE

    Wang, Pan; Ye, Feng; Chen, Xuejiao

    2018-01-01

    Smart homes have attracted much attention due to the expanding of Internet-of-Things (IoT) and smart devices. In this paper, we propose a smart gateway platform for data collection and awareness in smart home networks. A smart gateway will replace the traditional network gateway to connect the home network and the Internet. A smart home network supports different types of smart devices, such as in home IoT devices, smart phones, smart electric appliances, etc. A traditional network gateway is...

  10. Social networks

    CERN Document Server

    Etaner-Uyar, A Sima

    2014-01-01

    The present volume provides a comprehensive resource for practitioners and researchers alike-both those new to the field as well as those who already have some experience. The work covers Social Network Analysis theory and methods with a focus on current applications and case studies applied in various domains such as mobile networks, security, machine learning and health. With the increasing popularity of Web 2.0, social media has become a widely used communication platform. Parallel to this development, Social Network Analysis gained in importance as a research field, while opening up many

  11. Network Warrior

    CERN Document Server

    Donahue, Gary

    2011-01-01

    Pick up where certification exams leave off. With this practical, in-depth guide to the entire network infrastructure, you'll learn how to deal with real Cisco networks, rather than the hypothetical situations presented on exams like the CCNA. Network Warrior takes you step by step through the world of routers, switches, firewalls, and other technologies based on the author's extensive field experience. You'll find new content for MPLS, IPv6, VoIP, and wireless in this completely revised second edition, along with examples of Cisco Nexus 5000 and 7000 switches throughout. Topics include: An

  12. Managing Evolving Global Operations Networks

    DEFF Research Database (Denmark)

    Mykhaylenko, Alona; Wæhrens, Brian Vejrum; Johansen, John

    2015-01-01

    For many globally dispersed organisations, the home base (HB) is a historic locus of integrative and coordinating efforts that safeguard overall performance. However, the dynamism of global operations networks is increasingly pulling the centre of gravity away from the HB and dispersing it across...... the network, challenging the HB’s ability to sustain its centrality over time. To counteract this tendency, this paper addresses the gap in the literature regarding the development of the network management capability of the HB within the context of its network. Data was collected through a retrospective...... longitudinal case study of an intra-organisational operations network of one OEM and its three foreign subsidiaries. The findings suggest a row of strategic roles and corresponding managerial capabilities, which the HB needs to develop depending on the changing subsidiaries’ competencies and HB...

  13. Controllability of Surface Water Networks

    Science.gov (United States)

    Riasi, M. Sadegh; Yeghiazarian, Lilit

    2017-12-01

    To sustainably manage water resources, we must understand how to control complex networked systems. In this paper, we study surface water networks from the perspective of structural controllability, a concept that integrates classical control theory with graph-theoretic formalism. We present structural controllability theory and compute four metrics: full and target controllability, control centrality and control profile (FTCP) that collectively determine the structural boundaries of the system's control space. We use these metrics to answer the following questions: How does the structure of a surface water network affect its controllability? How to efficiently control a preselected subset of the network? Which nodes have the highest control power? What types of topological structures dominate controllability? Finally, we demonstrate the structural controllability theory in the analysis of a wide range of surface water networks, such as tributary, deltaic, and braided river systems.

  14. Network performance of a wireless sensor network for temperature monitoring in vineyards

    DEFF Research Database (Denmark)

    Liscano, Ramiro; Jacoub, John Khalil; Dersingh, Anand

    2011-01-01

    Wireless sensor networks (WSNs) are an emerging technology which can be used for outdoor environmental monitoring. This paper presents challenges that arose from the development and deployment of a WSN for environmental monitoring as well as network performance analysis of this network. Different...... components in our sensor network architecture are presented like the physical nodes, the sensor node code, and two messaging protocols; one for collecting sensor and network values and the other for sensor node commands. An information model for sensor nodes to support plug-and-play capabilities in sensor...... networks is also presented....

  15. Networks in Social Policy Problems

    Science.gov (United States)

    Vedres, Balázs; Scotti, Marco

    2012-08-01

    1. Introduction M. Scotti and B. Vedres; Part I. Information, Collaboration, Innovation: The Creative Power of Networks: 2. Dissemination of health information within social networks C. Dhanjal, S. Blanchemanche, S. Clemençon, A. Rona-Tas and F. Rossi; 3. Scientific teams and networks change the face of knowledge creation S. Wuchty, J. Spiro, B. F. Jones and B. Uzzi; 4. Structural folds: the innovative potential of overlapping groups B. Vedres and D. Stark; 5. Team formation and performance on nanoHub: a network selection challenge in scientific communities D. Margolin, K. Ognyanova, M. Huang, Y. Huang and N. Contractor; Part II. Influence, Capture, Corruption: Networks Perspectives on Policy Institutions: 6. Modes of coordination of collective action: what actors in policy making? M. Diani; 7. Why skewed distributions of pay for executives is the cause of much grief: puzzles and few answers so far B. Kogut and J.-S. Yang; 8. Networks of institutional capture: a case of business in the State apparatus E. Lazega and L. Mounier; 9. The social and institutional structure of corruption: some typical network configurations of corruption transactions in Hungary Z. Szántó, I. J. Tóth and S. Varga; Part III. Crisis, Extinction, World System Change: Network Dynamics on a Large Scale: 10. How creative elements help the recovery of networks after crisis: lessons from biology A. Mihalik, A. S. Kaposi, I. A. Kovács, T. Nánási, R. Palotai, Á. Rák, M. S. Szalay-Beko and P. Csermely; 11. Networks and globalization policies D. R. White; 12. Network science in ecology: the structure of ecological communities and the biodiversity question A. Bodini, S. Allesina and C. Bondavalli; 13. Supply security in the European natural gas pipeline network M. Scotti and B. Vedres; 14. Conclusions and outlook A.-L. Barabási; Index.

  16. Heterodox networks

    DEFF Research Database (Denmark)

    Lala, Purnima; Kumar, Ambuj

    2016-01-01

    It is imperative for the service providers to bring innovation in the network design to meet the exponential growth of mobile subscribers for multi-technology future wireless networks. As a matter of research, studies on providing services to moving subscriber groups aka ‘Place Time Capacity (PTC......)’ have not been considered much in the literature. In this article we present Heterodox networks as an innovative and alternate approach to handle the PTC congestion. We describe two different approaches to combat the PTC congestion where the traditional terrestrial infrastructure fails to provide......-Configurable Intelligent Distributed Antenna System (SCIDAS)’ that overlays intelligence over the conventional DAS architecture and latter is in the form of a swarm of intelligent hovering base stations working in a team to cooperatively resolve the PTC congestion at the Area of Event (AoE). A suitable network...

  17. Networking Japan

    DEFF Research Database (Denmark)

    Hansen, Annette Skovsted

    Human Resource Development was the first and remains an important pillar in Japanese foreign aid. I will argue that Japan has access to a global network of alumni who will co-define Japanese foreign aid in the future, because Japan has encouraged alumni societies and networking since 1965. A total...... of more than a million people in more than 100 countries have attended courses in Japan funded fully or partly by Japanese ODA since the inception of the technical assistance programs in 1954 through the Colombo Plan and since 1959 through the Association of Overseas Technical Scholarships (AOTS from 2009...... HIDA). Many of these alumni have and will in the future exchange ideas and keep contact not only to Japan, but also to fellow alumni around the globe and, thereby, practice south-south exchanges, which are made possible and traceable by their established alumni network and the World Network of Friends...

  18. Sentinel Network

    Science.gov (United States)

    The Sentinel Network is an integrated, electronic, national medical product safety initiative that compiles information about the safe and effective use of medical products accessible to patients and healthcare practitioners.

  19. Exchange Network

    Science.gov (United States)

    The Environmental Information Exchange Network (EN) is an Internet-based system used by state, tribal and territorial partners to securely share environmental and health information with one another and EPA.

  20. Diversity Networks

    Science.gov (United States)

    and professional growth of women through networking, mentoring and training. We strive to ensure that will be used. National Processing Center Seniors Leader: Jo Anne Hankins Champion: Eric Milliner NO

  1. Nepal Networking

    DEFF Research Database (Denmark)

    Hansen, Annette Skovsted

    , as a Danida fellow. Today, the older sister works in Nepal and the younger in Seattle, where they still make use of their personal networks including connections to their fellow alumni of technical assistance courses. Inspired by work on social remittances in combination with network theory , I argue......Technical Assistance courses have many functions apart from disseminating knowledge and information, one such function is to engender networks. During the course period, participants meet and establish contact and some of these contacts remain connections between alumni for many years after...... the courses are finished. The alumni networks depend on the uses they are put to by the individual alumni and the support they get from alumni and host countries. The United Nations initiated technical assistance courses in the late 1940s in order to train nationals from developing countries as a means...

  2. computer networks

    Directory of Open Access Journals (Sweden)

    N. U. Ahmed

    2002-01-01

    Full Text Available In this paper, we construct a new dynamic model for the Token Bucket (TB algorithm used in computer networks and use systems approach for its analysis. This model is then augmented by adding a dynamic model for a multiplexor at an access node where the TB exercises a policing function. In the model, traffic policing, multiplexing and network utilization are formally defined. Based on the model, we study such issues as (quality of service QoS, traffic sizing and network dimensioning. Also we propose an algorithm using feedback control to improve QoS and network utilization. Applying MPEG video traces as the input traffic to the model, we verify the usefulness and effectiveness of our model.

  3. Emergence of robustness in networks of networks

    Science.gov (United States)

    Roth, Kevin; Morone, Flaviano; Min, Byungjoon; Makse, Hernán A.

    2017-06-01

    A model of interdependent networks of networks (NONs) was introduced recently [Proc. Natl. Acad. Sci. (USA) 114, 3849 (2017), 10.1073/pnas.1620808114] in the context of brain activation to identify the neural collective influencers in the brain NON. Here we investigate the emergence of robustness in such a model, and we develop an approach to derive an exact expression for the random percolation transition in Erdös-Rényi NONs of this kind. Analytical calculations are in agreement with numerical simulations, and highlight the robustness of the NON against random node failures, which thus presents a new robust universality class of NONs. The key aspect of this robust NON model is that a node can be activated even if it does not belong to the giant mutually connected component, thus allowing the NON to be built from below the percolation threshold, which is not possible in previous models of interdependent networks. Interestingly, the phase diagram of the model unveils particular patterns of interconnectivity for which the NON is most vulnerable, thereby marking the boundary above which the robustness of the system improves with increasing dependency connections.

  4. Neural networks

    International Nuclear Information System (INIS)

    Denby, Bruce; Lindsey, Clark; Lyons, Louis

    1992-01-01

    The 1980s saw a tremendous renewal of interest in 'neural' information processing systems, or 'artificial neural networks', among computer scientists and computational biologists studying cognition. Since then, the growth of interest in neural networks in high energy physics, fueled by the need for new information processing technologies for the next generation of high energy proton colliders, can only be described as explosive

  5. Pintadas network

    OpenAIRE

    Cruz, Maria do Carmo Meirelles T.

    2006-01-01

    The Pintadas Network has been organized in Pintadas, a small municipality (11.254 inhabitants) in Bahia, located in the semi-arid region. It has been composed by civil society organizacions (social, productive, cultural and religious organizations and a credit cooperative), with support from the local town hall and from national and international institutions. The Network is a space for articulation, which intends to formulate, execute, follow-up, inspect and evaluate the municipal public pol...

  6. Organizational Networks

    DEFF Research Database (Denmark)

    Grande, Bård; Sørensen, Ole Henning

    1998-01-01

    The paper focuses on the concept of organizational networks. Four different uses of the concept of organizational network are identified and critically discussed. Special focus is placed on how information and communication technologies as communication mediators and cognitive pictures influence...... the organizational forms discussed in the paper. It is asserted that the underlying organizational phenomena are not changing but that the manifestations and representations are shifting due to technological developments....

  7. 2016 Network Games, Control, and Optimization Conference

    CERN Document Server

    Jimenez, Tania; Solan, Eilon

    2017-01-01

    This contributed volume offers a collection of papers presented at the 2016 Network Games, Control, and Optimization conference (NETGCOOP), held at the University of Avignon in France, November 23-25, 2016. These papers highlight the increasing importance of network control and optimization in many networking application domains, such as mobile and fixed access networks, computer networks, social networks, transportation networks, and, more recently, electricity grids and biological networks. Covering a wide variety of both theoretical and applied topics in the areas listed above, the authors explore several conceptual and algorithmic tools that are needed for efficient and robust control operation, performance optimization, and better understanding the relationships between entities that may be acting cooperatively or selfishly in uncertain and possibly adversarial environments. As such, this volume will be of interest to applied mathematicians, computer scientists, engineers, and researchers in other relate...

  8. Electricity networks: how 'natural' is the monopoly?

    International Nuclear Information System (INIS)

    Kuenneke, Rolf W.

    1999-01-01

    This article deals with the changing economic characteristics of the electricity network. Traditionally, electricity networks are considered natural monopolies for various kinds of market failures coincide in this essential part of the electricity infrastructure. Technological induced complementarities between nodes and links are causing network externalities, economies of scale, a high degree of mono-functionality, collective good characteristics and an inherent tendency towards concentrated market structures. It is argued that recent technological trends imply a dramatic change of the network economics, leading to possibilities of inter- and intra-network competition, as well as inter fuel competition. The possible implications for the regulatory framework of this sector are addressed. (Author)

  9. Complex Networks

    CERN Document Server

    Evsukoff, Alexandre; González, Marta

    2013-01-01

    In the last decade we have seen the emergence of a new inter-disciplinary field focusing on the understanding of networks which are dynamic, large, open, and have a structure sometimes called random-biased. The field of Complex Networks is helping us better understand many complex phenomena such as the spread of  deseases, protein interactions, social relationships, to name but a few. Studies in Complex Networks are gaining attention due to some major scientific breakthroughs proposed by network scientists helping us understand and model interactions contained in large datasets. In fact, if we could point to one event leading to the widespread use of complex network analysis is the availability of online databases. Theories of Random Graphs from Erdös and Rényi from the late 1950s led us to believe that most networks had random characteristics. The work on large online datasets told us otherwise. Starting with the work of Barabási and Albert as well as Watts and Strogatz in the late 1990s, we now know th...

  10. AfSIS MODIS Collection: Vegetation Indices, April 2014

    Data.gov (United States)

    Center for International Earth Science Information Network, Columbia University — The Africa Soil Information Service (AfSIS) Moderate Resolution Imaging Spectroradiometer (MODIS) Collection's Vegetation Indices data set contains rasters with the...

  11. Neural Networks

    International Nuclear Information System (INIS)

    Smith, Patrick I.

    2003-01-01

    Physicists use large detectors to measure particles created in high-energy collisions at particle accelerators. These detectors typically produce signals indicating either where ionization occurs along the path of the particle, or where energy is deposited by the particle. The data produced by these signals is fed into pattern recognition programs to try to identify what particles were produced, and to measure the energy and direction of these particles. Ideally, there are many techniques used in this pattern recognition software. One technique, neural networks, is particularly suitable for identifying what type of particle caused by a set of energy deposits. Neural networks can derive meaning from complicated or imprecise data, extract patterns, and detect trends that are too complex to be noticed by either humans or other computer related processes. To assist in the advancement of this technology, Physicists use a tool kit to experiment with several neural network techniques. The goal of this research is interface a neural network tool kit into Java Analysis Studio (JAS3), an application that allows data to be analyzed from any experiment. As the final result, a physicist will have the ability to train, test, and implement a neural network with the desired output while using JAS3 to analyze the results or output. Before an implementation of a neural network can take place, a firm understanding of what a neural network is and how it works is beneficial. A neural network is an artificial representation of the human brain that tries to simulate the learning process [5]. It is also important to think of the word artificial in that definition as computer programs that use calculations during the learning process. In short, a neural network learns by representative examples. Perhaps the easiest way to describe the way neural networks learn is to explain how the human brain functions. The human brain contains billions of neural cells that are responsible for processing

  12. Antagonistic Phenomena in Network Dynamics

    Science.gov (United States)

    Motter, Adilson E.; Timme, Marc

    2018-03-01

    Recent research on the network modeling of complex systems has led to a convenient representation of numerous natural, social, and engineered systems that are now recognized as networks of interacting parts. Such systems can exhibit a wealth of phenomena that not only cannot be anticipated from merely examining their parts, as per the textbook definition of complexity, but also challenge intuition even when considered in the context of what is now known in network science. Here, we review the recent literature on two major classes of such phenomena that have far-reaching implications: (a) antagonistic responses to changes of states or parameters and (b) coexistence of seemingly incongruous behaviors or properties - both deriving from the collective and inherently decentralized nature of the dynamics. They include effects as diverse as negative compressibility in engineered materials, rescue interactions in biological networks, negative resistance in fluid networks, and the Braess paradox occurring across transport and supply networks. They also include remote synchronization, chimera states, and the converse of symmetry breaking in brain, power-grid, and oscillator networks as well as remote control in biological and bioinspired systems. By offering a unified view of these various scenarios, we suggest that they are representative of a yet broader class of unprecedented network phenomena that ought to be revealed and explained by future research.

  13. Neuromorphic atomic switch networks.

    Directory of Open Access Journals (Sweden)

    Audrius V Avizienis

    Full Text Available Efforts to emulate the formidable information processing capabilities of the brain through neuromorphic engineering have been bolstered by recent progress in the fabrication of nonlinear, nanoscale circuit elements that exhibit synapse-like operational characteristics. However, conventional fabrication techniques are unable to efficiently generate structures with the highly complex interconnectivity found in biological neuronal networks. Here we demonstrate the physical realization of a self-assembled neuromorphic device which implements basic concepts of systems neuroscience through a hardware-based platform comprised of over a billion interconnected atomic-switch inorganic synapses embedded in a complex network of silver nanowires. Observations of network activation and passive harmonic generation demonstrate a collective response to input stimulus in agreement with recent theoretical predictions. Further, emergent behaviors unique to the complex network of atomic switches and akin to brain function are observed, namely spatially distributed memory, recurrent dynamics and the activation of feedforward subnetworks. These devices display the functional characteristics required for implementing unconventional, biologically and neurally inspired computational methodologies in a synthetic experimental system.

  14. The Falcon Telescope Network

    Science.gov (United States)

    Chun, F.; Tippets, R.; Dearborn, M.; Gresham, K.; Freckleton, R.; Douglas, M.

    2014-09-01

    The Falcon Telescope Network (FTN) is a global network of small aperture telescopes developed by the Center for Space Situational Awareness Research in the Department of Physics at the United States Air Force Academy (USAFA). Consisting of commercially available equipment, the FTN is a collaborative effort between USAFA and other educational institutions ranging from two- and four-year colleges to major research universities. USAFA provides the equipment (e.g. telescope, mount, camera, filter wheel, dome, weather station, computers and storage devices) while the educational partners provide the building and infrastructure to support an observatory. The user base includes USAFA along with K-12 and higher education faculty and students. Since the FTN has a general use purpose, objects of interest include satellites, astronomical research, and STEM support images. The raw imagery, all in the public domain, will be accessible to FTN partners and will be archived at USAFA in the Cadet Space Operations Center. FTN users will be able to submit observational requests via a web interface. The requests will then be prioritized based on the type of user, the object of interest, and a user-defined priority. A network wide schedule will be developed every 24 hours and each FTN site will autonomously execute its portion of the schedule. After an observational request is completed, the FTN user will receive notification of collection and a link to the data. The Falcon Telescope Network is an ambitious endeavor, but demonstrates the cooperation that can be achieved by multiple educational institutions.

  15. Vulnerability of complex networks

    Science.gov (United States)

    Mishkovski, Igor; Biey, Mario; Kocarev, Ljupco

    2011-01-01

    We consider normalized average edge betweenness of a network as a metric of network vulnerability. We suggest that normalized average edge betweenness together with is relative difference when certain number of nodes and/or edges are removed from the network is a measure of network vulnerability, called vulnerability index. Vulnerability index is calculated for four synthetic networks: Erdős-Rényi (ER) random networks, Barabási-Albert (BA) model of scale-free networks, Watts-Strogatz (WS) model of small-world networks, and geometric random networks. Real-world networks for which vulnerability index is calculated include: two human brain networks, three urban networks, one collaboration network, and two power grid networks. We find that WS model of small-world networks and biological networks (human brain networks) are the most robust networks among all networks studied in the paper.

  16. Communication Network Architectures Based on Ethernet Passive Optical Network for Offshore Wind Power Farms

    Directory of Open Access Journals (Sweden)

    Mohamed A. Ahmed

    2016-03-01

    Full Text Available Nowadays, with large-scale offshore wind power farms (WPFs becoming a reality, more efforts are needed to maintain a reliable communication network for WPF monitoring. Deployment topologies, redundancy, and network availability are the main items to enhance the communication reliability between wind turbines (WTs and control centers. Traditional communication networks for monitoring and control (i.e., supervisory control and data acquisition (SCADA systems using switched gigabit Ethernet will not be sufficient for the huge amount of data passing through the network. In this paper, the optical power budget, optical path loss, reliability, and network cost of the proposed Ethernet Passive Optical Network (EPON-based communication network for small-size offshore WPFs have been evaluated for five different network architectures. The proposed network model consists of an optical network unit device (ONU deployed on the WT side for collecting data from different internal networks. All ONUs from different WTs are connected to a central optical line terminal (OLT, placed in the control center. There are no active electronic elements used between the ONUs and the OLT, which reduces the costs and complexity of maintenance and deployment. As fiber access networks without any protection are characterized by poor reliability, three different protection schemes have been configured, explained, and discussed. Considering the cost of network components, the total implementation expense of different architectures with, or without, protection have been calculated and compared. The proposed network model can significantly contribute to the communication network architecture for next generation WPFs.

  17. Mechanisms for Prolonging Network Lifetime in Wireless Sensor Networks

    Science.gov (United States)

    Yang, Yinying

    2010-01-01

    Sensors are used to monitor and control the physical environment. A Wireless Sensor Network (WSN) is composed of a large number of sensor nodes that are densely deployed either inside the phenomenon or very close to it [18][5]. Sensor nodes measure various parameters of the environment and transmit data collected to one or more sinks, using…

  18. Towards modern petrological collections

    NARCIS (Netherlands)

    Kriegsman, L.M.

    2004-01-01

    Petrological collections result from sampling for academic research, for aesthetic or commercial reasons, and to document natural diversity. Selection criteria for reducing and enhancing collections include adequate documentation, potential for future use, information density, time and money

  19. Network Survivability

    DEFF Research Database (Denmark)

    Marzo, José L.; Stidsen, Thomas Riis; Ruepp, Sarah Renée

    2010-01-01

    – are vital to modern services such as mobile telephony, online banking and VoIP. This book examines communication networking from a mathematical viewpoint. The contributing authors took part in the European COST action 293 – a four-year program of multidisciplinary research on this subject. In this book...... they offer introductory overviews and state-of-the-art assessments of current and future research in the fields of broadband, optical, wireless and ad hoc networks. Particular topics of interest are design, optimization, robustness and energy consumption. The book will be of interest to graduate students......, researchers and practitioners in the areas of networking, theoretical computer science, operations research, distributed computing and mathematics....

  20. Nuclear networking.

    Science.gov (United States)

    Xie, Wei; Burke, Brian

    2017-07-04

    Nuclear lamins are intermediate filament proteins that represent important structural components of metazoan nuclear envelopes (NEs). By combining proteomics and superresolution microscopy, we recently reported that both A- and B-type nuclear lamins form spatially distinct filament networks at the nuclear periphery of mouse fibroblasts. In particular, A-type lamins exhibit differential association with nuclear pore complexes (NPCs). Our studies reveal that the nuclear lamina network in mammalian somatic cells is less ordered and more complex than that of amphibian oocytes, the only other system in which the lamina has been visualized at high resolution. In addition, the NPC component Tpr likely links NPCs to the A-type lamin network, an association that appears to be regulated by C-terminal modification of various A-type lamin isoforms. Many questions remain, however, concerning the structure and assembly of lamin filaments, as well as with their mode of association with other nuclear components such as peripheral chromatin.

  1. Telecommunication Networks

    DEFF Research Database (Denmark)

    Olsen, Rasmus Løvenstein; Balachandran, Kartheepan; Hald, Sara Ligaard

    2014-01-01

    In this chapter, we look into the role of telecommunication networks and their capability of supporting critical infrastructure systems and applications. The focus is on smart grids as the key driving example, bearing in mind that other such systems do exist, e.g., water management, traffic control......, etc. First, the role of basic communication is examined with a focus on critical infrastructures. We look at heterogenic networks and standards for smart grids, to give some insight into what has been done to ensure inter-operability in this direction. We then go to the physical network, and look...... threats to the critical infrastructure. Finally, before our conclusions and outlook, we give a brief overview of some key activities in the field and what research directions are currently investigated....

  2. Network interruptions

    CERN Multimedia

    2005-01-01

    On Sunday 12 June 2005, a site-wide security software upgrade will be performed on all CERN network equipment. This maintenance operation will cause at least 2 short network interruptions of 2 minutes on each equipment item. There are hundreds of such items across the CERN site (Meyrin, Prévessin and all SPS and LHC pits), and it will thus take the whole day to treat them all. All network users and services will be affected. Central batch computing services will be interrupted during this period, expected to last from 8 a.m. until late evening. Job submission will still be possible but no jobs will actually be run. It is hoped to complete the computer centre upgrades in the morning so that stable access can be restored to lxplus, afs and nice services as soon as possible; this cannot be guaranteed, however. The opportunity will be used to interrupt and perform upgrades on the CERN Document Servers.

  3. Small diameter symmetric networks from linear groups

    Science.gov (United States)

    Campbell, Lowell; Carlsson, Gunnar E.; Dinneen, Michael J.; Faber, Vance; Fellows, Michael R.; Langston, Michael A.; Moore, James W.; Multihaupt, Andrew P.; Sexton, Harlan B.

    1992-01-01

    In this note is reported a collection of constructions of symmetric networks that provide the largest known values for the number of nodes that can be placed in a network of a given degree and diameter. Some of the constructions are in the range of current potential engineering significance. The constructions are Cayley graphs of linear groups obtained by experimental computation.

  4. Network Coding Protocols for Data Gathering Applications

    DEFF Research Database (Denmark)

    Nistor, Maricica; Roetter, Daniel Enrique Lucani; Barros, João

    2015-01-01

    Tunable sparse network coding (TSNC) with various sparsity levels of the coded packets and different feedback mechanisms is analysed in the context of data gathering applications in multi-hop networks. The goal is to minimize the completion time, i.e., the total time required to collect all data ...

  5. Temporal fidelity in dynamic social networks

    DEFF Research Database (Denmark)

    Stopczynski, Arkadiusz; Sapiezynski, Piotr; Pentland, Alex ‘Sandy’

    2015-01-01

    of the network dynamics can be used to inform the process of measuring social networks. The details of measurement are of particular importance when considering dynamic processes where minute-to-minute details are important, because collection of physical proximity interactions with high temporal resolution...

  6. Synchronization in oscillatory networks

    CERN Document Server

    Osipov, Grigory V; Zhou, Changsong

    2007-01-01

    The formation of collective behavior in large ensembles or networks of coupled oscillatory elements is one of the oldest and most fundamental aspects of dynamical systems theory. Potential and present applications span a vast spectrum of fields ranging from physics, chemistry, geoscience, through life- and neurosciences to engineering, the economic and the social sciences. This work systematically investigates a large number of oscillatory network configurations that are able to describe many real systems such as electric power grids, lasers or the heart muscle - to name but a few. This book is conceived as an introduction to the field for graduate students in physics and applied mathematics as well as being a compendium for researchers from any field of application interested in quantitative models.

  7. Modular sensor network node

    Science.gov (United States)

    Davis, Jesse Harper Zehring [Berkeley, CA; Stark, Jr., Douglas Paul; Kershaw, Christopher Patrick [Hayward, CA; Kyker, Ronald Dean [Livermore, CA

    2008-06-10

    A distributed wireless sensor network node is disclosed. The wireless sensor network node includes a plurality of sensor modules coupled to a system bus and configured to sense a parameter. The parameter may be an object, an event or any other parameter. The node collects data representative of the parameter. The node also includes a communication module coupled to the system bus and configured to allow the node to communicate with other nodes. The node also includes a processing module coupled to the system bus and adapted to receive the data from the sensor module and operable to analyze the data. The node also includes a power module connected to the system bus and operable to generate a regulated voltage.

  8. Determination of collective behavior of the financial market.

    Science.gov (United States)

    Li, Shouwei; Xu, Tao; He, Jianmin

    2016-01-01

    In this paper, we adopt the network synchronization to measure the collective behavior in the financial market, and then analyze the factors that affect the collective behavior. Based on the data from the Chinese financial market, we find that the clustering coefficient, the average shortest path length and the volatility fluctuation have a positive effect on the collective behavior respectively, while the average return has a negative effect on it; the effect of the average shortest path length on the collective behavior is the greatest in the above four variables; the above results are robust against the window size and the time interval between adjacent windows of the stock network; the effect of network structures and stock market properties on the collective behavior during the financial crisis is the same as those during other periods.

  9. Old tropical botanical collections

    DEFF Research Database (Denmark)

    Friis, Ib

    2017-01-01

    The early history of botanical collections is reviewed, with particular emphasis on old collections from the tropics. The information available about older and newer botanical collections from the tropics was much improved after World War Two, including better lists of validly published names, more...

  10. Managing Networks

    DEFF Research Database (Denmark)

    Jørgensen, Heidi; Vintergaard, Christian

    Logically it seems that companies pursuing different business strategies wouldalso manage their relationships with other firms accordingly. Nevertheless, due tothe lack of research in the field of network strategies, this link still remainsinadequately examined. Based on the well-known framework...... isprovided, that the relation between a company's strategy, structure and processesin fact have a considerable influence on its pattern of network behaviour. Threecase studies from the Danish biotech industry exemplify and illustrate how acompany's strategy is directly correlated with how it manages its...... of networkbehaviour, knowing how to manage this relation becomes essential, especiallyduring the development of new strategies....

  11. Networking activities in technology-based entrepreneurial teams

    DEFF Research Database (Denmark)

    Neergaard, Helle

    2005-01-01

    Based on social network theoy, this article investigates the distribution of networking roles and responsibilities in entrepreneurial founding teams. Its focus is on the team as a collection of individuals, thus allowing the research to address differences in networking patterns. It identifies six...... central networking activities and shows that not all founding team members are equally active 'networkers'. The analyses show that team members prioritize different networking activities and that one member in particular has extensive networking activities whereas other memebrs of the team are more...

  12. Searching Information Sources in Networks

    Science.gov (United States)

    2017-06-14

    with partial observations,” in AAAI Conference on Artificial Intelligence , 2017. [6] D. J. Watts and S. H. Strogatz, “Collective dynamics of ‘small...critical infrastructure of our society. The failure of the power grid network will have catastrophic impacts on water supplies, transportation

  13. Maximum Parsimony on Phylogenetic networks

    Science.gov (United States)

    2012-01-01

    Background Phylogenetic networks are generalizations of phylogenetic trees, that are used to model evolutionary events in various contexts. Several different methods and criteria have been introduced for reconstructing phylogenetic trees. Maximum Parsimony is a character-based approach that infers a phylogenetic tree by minimizing the total number of evolutionary steps required to explain a given set of data assigned on the leaves. Exact solutions for optimizing parsimony scores on phylogenetic trees have been introduced in the past. Results In this paper, we define the parsimony score on networks as the sum of the substitution costs along all the edges of the network; and show that certain well-known algorithms that calculate the optimum parsimony score on trees, such as Sankoff and Fitch algorithms extend naturally for networks, barring conflicting assignments at the reticulate vertices. We provide heuristics for finding the optimum parsimony scores on networks. Our algorithms can be applied for any cost matrix that may contain unequal substitution costs of transforming between different characters along different edges of the network. We analyzed this for experimental data on 10 leaves or fewer with at most 2 reticulations and found that for almost all networks, the bounds returned by the heuristics matched with the exhaustively determined optimum parsimony scores. Conclusion The parsimony score we define here does not directly reflect the cost of the best tree in the network that displays the evolution of the character. However, when searching for the most parsimonious network that describes a collection of characters, it becomes necessary to add additional cost considerations to prefer simpler structures, such as trees over networks. The parsimony score on a network that we describe here takes into account the substitution costs along the additional edges incident on each reticulate vertex, in addition to the substitution costs along the other edges which are

  14. Satellite image collection optimization

    Science.gov (United States)

    Martin, William

    2002-09-01

    Imaging satellite systems represent a high capital cost. Optimizing the collection of images is critical for both satisfying customer orders and building a sustainable satellite operations business. We describe the functions of an operational, multivariable, time dynamic optimization system that maximizes the daily collection of satellite images. A graphical user interface allows the operator to quickly see the results of what if adjustments to an image collection plan. Used for both long range planning and daily collection scheduling of Space Imaging's IKONOS satellite, the satellite control and tasking (SCT) software allows collection commands to be altered up to 10 min before upload to the satellite.

  15. Collection time again.

    Science.gov (United States)

    Elder, D L

    1984-01-01

    Looking forward to your next round of collection calls? Few of us do, yet collections play a vital role in every group practice, large or small. This crop of practical collection tips is guaranteed to boost the morale of everyone involved in the collection process. Not only are the basics of a good collection call set down, but result-getting responses to frequent debtor excuses are provided. Telephoning the debtor patient need not be a dreaded task. Just have confidence, keep in mind that the patient does owe you for services rendered in good faith, and pick up the phone--it's a snap!

  16. Percolation of interdependent network of networks

    International Nuclear Information System (INIS)

    Havlin, Shlomo; Stanley, H. Eugene; Bashan, Amir; Gao, Jianxi; Kenett, Dror Y.

    2015-01-01

    Complex networks appear in almost every aspect of science and technology. Previous work in network theory has focused primarily on analyzing single networks that do not interact with other networks, despite the fact that many real-world networks interact with and depend on each other. Very recently an analytical framework for studying the percolation properties of interacting networks has been introduced. Here we review the analytical framework and the results for percolation laws for a Network Of Networks (NONs) formed by n interdependent random networks. The percolation properties of a network of networks differ greatly from those of single isolated networks. In particular, because the constituent networks of a NON are connected by node dependencies, a NON is subject to cascading failure. When there is strong interdependent coupling between networks, the percolation transition is discontinuous (first-order) phase transition, unlike the well-known continuous second-order transition in single isolated networks. Moreover, although networks with broader degree distributions, e.g., scale-free networks, are more robust when analyzed as single networks, they become more vulnerable in a NON. We also review the effect of space embedding on network vulnerability. It is shown that for spatially embedded networks any finite fraction of dependency nodes will lead to abrupt transition

  17. Evaluation of Persian Professional Web Social Networks\\\\\\' Features, to Provide a Suitable Solution for Optimization of These Networks in Iran

    Directory of Open Access Journals (Sweden)

    Nadjla Hariri

    2013-03-01

    Full Text Available This study aimed to determine the status of Persian professional web social networks' features and provide a suitable solution for optimization of these networks in Iran. The research methods were library research and evaluative method, and study population consisted of 10 Persian professional web social networks. In this study, for data collection, a check list of social networks important tools and features was used. According to the results, “Cloob”, “IR Experts” and “Doreh” were the most compatible networks with the criteria of social networks. Finally, some solutions were presented for optimization of capabilities of Persian professional web social networks.

  18. Availability Issues in Wireless Visual Sensor Networks

    Science.gov (United States)

    Costa, Daniel G.; Silva, Ivanovitch; Guedes, Luiz Affonso; Vasques, Francisco; Portugal, Paulo

    2014-01-01

    Wireless visual sensor networks have been considered for a large set of monitoring applications related with surveillance, tracking and multipurpose visual monitoring. When sensors are deployed over a monitored field, permanent faults may happen during the network lifetime, reducing the monitoring quality or rendering parts or the entire network unavailable. In a different way from scalar sensor networks, camera-enabled sensors collect information following a directional sensing model, which changes the notions of vicinity and redundancy. Moreover, visual source nodes may have different relevancies for the applications, according to the monitoring requirements and cameras' poses. In this paper we discuss the most relevant availability issues related to wireless visual sensor networks, addressing availability evaluation and enhancement. Such discussions are valuable when designing, deploying and managing wireless visual sensor networks, bringing significant contributions to these networks. PMID:24526301

  19. Collective Lyapunov modes

    International Nuclear Information System (INIS)

    Takeuchi, Kazumasa A; Chaté, Hugues

    2013-01-01

    We show, using covariant Lyapunov vectors in addition to standard Lyapunov analysis, that there exists a set of collective Lyapunov modes in large chaotic systems exhibiting collective dynamics. Associated with delocalized Lyapunov vectors, they act collectively on the trajectory and hence characterize the instability of its collective dynamics. We further develop, for globally coupled systems, a connection between these collective modes and the Lyapunov modes in the corresponding Perron–Frobenius equation. We thereby address the fundamental question of the effective dimension of collective dynamics and discuss the extensivity of chaos in the presence of collective dynamics. This article is part of a special issue of Journal of Physics A: Mathematical and Theoretical devoted to ‘Lyapunov analysis: from dynamical systems theory to applications’. (paper)

  20. Network Society

    DEFF Research Database (Denmark)

    Clausen, Lars; Tække, Jesper

    2017-01-01

    the five strands of theory on the network society. Each theoretical position has its specific implications for acting toward strategic goals. In its entirety, the five perspectives give a thorough understanding of the conditions for successful strategic communication in the 21st century....

  1. Network Society

    DEFF Research Database (Denmark)

    Clausen, Lars; Tække, Jesper

    2018-01-01

    the five strands of theory on the network society. Each theoretical position has its specific implications for acting toward strategic goals. In its entirety, the five perspectives give a thorough understanding of the conditions for successful strategic communication in the 21st century....

  2. Network Views

    Science.gov (United States)

    Alexander, Louis

    2010-01-01

    The world changed in 2008. The financial crisis brought with it a deepening sense of insecurity, and the desire to be connected to a network increased. Throughout the summer and fall of 2008, events were unfolding with alarming rapidity. The Massachusetts Institute of Technology (MIT) Alumni Association wanted to respond to this change in the…

  3. Network Coding

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 15; Issue 7. Network Coding. K V Rashmi Nihar B Shah P Vijay Kumar. General Article Volume 15 Issue 7 July 2010 pp 604-621. Fulltext. Click here to view fulltext PDF. Permanent link: https://www.ias.ac.in/article/fulltext/reso/015/07/0604-0621 ...

  4. Global Networking.

    Science.gov (United States)

    Lynch, Clifford

    1997-01-01

    Discusses the state of the Internet. Highlights include the magnitude of the infrastructure, costs, its increasing pace, constraints in international links, provision of network capacity to homes and small businesses, cable television modems, political and cultural problems, the digital library concept, search engines, the failure of personal…

  5. Shapley ratings in brain networks

    Directory of Open Access Journals (Sweden)

    Rolf Kötter

    2007-11-01

    Full Text Available Recent applications of network theory to brain networks as well as the expanding empirical databases of brain architecture spawn an interest in novel techniques for analyzing connectivity patterns in the brain. Treating individual brain structures as nodes in a directed graph model permits the application of graph theoretical concepts to the analysis of these structures within their large-scale connectivity networks. In this paper, we explore the application of concepts from graph and game theory toward this end. Specifically, we utilize the Shapley value principle, which assigns a rank to players in a coalition based upon their individual contributions to the collective profit of that coalition, to assess the contributions of individual brain structures to the graph derived from the global connectivity network. We report Shapley values for variations of a prefrontal network, as well as for a visual cortical network, which had both been extensively investigated previously. This analysis highlights particular nodes as strong or weak contributors to global connectivity. To understand the nature of their contribution, we compare the Shapley values obtained from these networks and appropriate controls to other previously described nodal measures of structural connectivity. We find a strong correlation between Shapley values and both betweenness centrality and connection density. Moreover, a stepwise multiple linear regression analysis indicates that approximately 79% of the variance in Shapley values obtained from random networks can be explained by betweenness centrality alone. Finally, we investigate the effects of local lesions on the Shapley ratings, showing that the present networks have an immense structural resistance to degradation. We discuss our results highlighting the use of such measures for characterizing the organization and functional role of brain networks.

  6. 75 FR 69671 - Agency Information Collection Activities: Proposed Collection; Comment Request

    Science.gov (United States)

    2010-11-15

    ... behavior. All 147 networked crisis centers will complete the Web-based Crisis Center Survey annually. The Survey requests information about organizational structure, staffing, scope of services, call center operations, quality assurance, community outreach/marketing, telephone equipment, data collection, and...

  7. Incremental Centrality Algorithms for Dynamic Network Analysis

    Science.gov (United States)

    2013-08-01

    literature.   7.1.3 Small World Networks In 1998, Watts and Strogatz introduced a model that starts with a regular lattice (ring) of n nodes and...and S. Strogatz , "Collective Dynamics of ‘Small-World’ Networks," Nature, vol. 393, pp. 440-442, 1998. [13] T. Opsahl, "Structure and Evolution of...34On Random Graphs," Publicationes Mathematicae, vol. 6, 1959. [167] D.J. Watts and S.H. Strogatz , "Collective Dynamics of ‘Small-World’ Networks

  8. On Model Design for Simulation of Collective Intelligence

    NARCIS (Netherlands)

    Schut, M.C.

    2010-01-01

    The study of collective intelligence (CI) systems is increasingly gaining interest in a variety of research and application domains. Those domains range from existing research areas such as computer networks and collective robotics to upcoming areas of agent-based and insect-based computing; also

  9. Comparing personal image collections with PICTuReVis

    NARCIS (Netherlands)

    van der Corput, P.N.A.; van Wijk, J.J.

    2017-01-01

    Digital image collections contain a wealth of information, which for instance can be used to trace illegal activities and investigate criminal networks. We present a method that enables analysts to reveal relations among people, based on the patterns in their collections. Similar temporal and

  10. Connective Versus Collective Action in Social Movements

    DEFF Research Database (Denmark)

    Lundgaard, Daniel; Razmerita, Liana

    of connective action is are sult of mediating technologies especially web 2.0 that inspire and affords emergent digitally networked action, based on large‐scale self‐organized, fluid and weak‐tied networks (Ibid.). These logics are investigated in three different social media movements; #YesAllWomen, #Black......LivesMatter and the #IceBucketChallenge by analyzing Twitter and Facebook data from key periods of these movements,through a net nographic study. In particular, this study has investigated the following research questions: How are the logics of collective and connective action reflected in online social media interactions...... in large‐scale, weak‐tied networks with morphing boundaries. The nature of social media ensures that personalized action frames (e.g. personal stories or memes) and the self‐motivating act of voluntary sharing, as well how this act is reciprocated, is integral for the potential reach and impact...

  11. Ecological network analysis: network construction

    NARCIS (Netherlands)

    Fath, B.D.; Scharler, U.M.; Ulanowicz, R.E.; Hannon, B.

    2007-01-01

    Ecological network analysis (ENA) is a systems-oriented methodology to analyze within system interactions used to identify holistic properties that are otherwise not evident from the direct observations. Like any analysis technique, the accuracy of the results is as good as the data available, but

  12. Reflections on collectivity

    International Nuclear Information System (INIS)

    Feshbach, H.

    1983-01-01

    Comments are made on papers presented to the International School of Nuclear Physics, Erice (1982) concerning collective bands and collectivity in nuclei. The importance of these collective modes of motion, the role of the Bohr-Mottelson model and the Interacting Boson Models (IBM-1 and IBM-2), and experimental evidence presented by a number of workers, are examined. The extensions of the models to take into account additional degrees of freedom both collective and non-collective, the discovery of new collective modes such as those corresponding to tri-axial shapes, and the possible existence of additional symmetries reported at the meeting, are discussed. Finally the importance is examined of relating the phenomenological models to a more fundamental underlying theory, which has been taken to be the nuclear shell model. (U.K.)

  13. New trends in computational collective intelligence

    CERN Document Server

    Kim, Sang-Wook; Trawiński, Bogdan

    2015-01-01

    This book consists of 20 chapters in which the authors deal with different theoretical and practical aspects of new trends in Collective Computational Intelligence techniques. Computational Collective Intelligence methods and algorithms are one the current trending research topics from areas related to Artificial Intelligence, Soft Computing or Data Mining among others. Computational Collective Intelligence is a rapidly growing field that is most often understood as an AI sub-field dealing with soft computing methods which enable making group decisions and processing knowledge among autonomous units acting in distributed environments. Web-based Systems, Social Networks, and Multi-Agent Systems very often need these tools for working out consistent knowledge states, resolving conflicts and making decisions. The chapters included in this volume cover a selection of topics and new trends in several domains related to Collective Computational Intelligence: Language and Knowledge Processing, Data Mining Methods an...

  14. From Isolated to Networked: A Paradigmatic Shift in Mitochondrial Physiology

    OpenAIRE

    Aon, Miguel A.

    2010-01-01

    A new paradigm of mitochondrial function in networks is emerging which includes, without undermining, the glorious and still useful paradigm of the isolated mitochondrion. The mitochondrial network paradigm introduces new concepts, tools, and analytical techniques. Among them is that mitochondrial function in networks exhibits interdependence and multiplicative effects based on synchronization mechanisms, which involve communication between mitochondrial neighbors. The collective dynamics of ...

  15. Relationship between Social Networks Adoption and Social Intelligence

    Science.gov (United States)

    Gunduz, Semseddin

    2017-01-01

    The purpose of this study was to set forth the relationship between the individuals' states to adopt social networks and social intelligence and analyze both concepts according to various variables. Research data were collected from 1145 social network users in the online media by using the Adoption of Social Network Scale and Social Intelligence…

  16. Preparing for a Career as a Network Engineer

    Science.gov (United States)

    Morris, Gerard; Fustos, Janos; Haga, Wayne

    2012-01-01

    A network engineer is an Information Technology (IT) professional who designs, implements, maintains, and troubleshoots computer networks. While the United States is still experiencing relatively high unemployment, demand for network engineers remains strong. To determine what skills employers are looking for, data was collected and analyzed from…

  17. Mob control models of threshold collective behavior

    CERN Document Server

    Breer, Vladimir V; Rogatkin, Andrey D

    2017-01-01

    This book presents mathematical models of mob control with threshold (conformity) collective decision-making of the agents. Based on the results of analysis of the interconnection between the micro- and macromodels of active network structures, it considers the static (deterministic, stochastic and game-theoretic) and dynamic (discrete- and continuous-time) models of mob control, and highlights models of informational confrontation. Many of the results are applicable not only to mob control problems, but also to control problems arising in social groups, online social networks, etc. Aimed at researchers and practitioners, it is also a valuable resource for undergraduate and postgraduate students as well as doctoral candidates specializing in the field of collective behavior modeling.

  18. Collecting Taxes Database

    Data.gov (United States)

    US Agency for International Development — The Collecting Taxes Database contains performance and structural indicators about national tax systems. The database contains quantitative revenue performance...

  19. Sonata: Query-Driven Network Telemetry

    KAUST Repository

    Gupta, Arpit; Harrison, Rob; Pawar, Ankita; Birkner, Rü diger; Canini, Marco; Feamster, Nick; Rexford, Jennifer; Willinger, Walter

    2017-01-01

    Operating networks depends on collecting and analyzing measurement data. Current technologies do not make it easy to do so, typically because they separate data collection (e.g., packet capture or flow monitoring) from analysis, producing either too much data to answer a general question or too little data to answer a detailed question. In this paper, we present Sonata, a network telemetry system that uses a uniform query interface to drive the joint collection and analysis of network traffic. Sonata takes the advantage of two emerging technologies---streaming analytics platforms and programmable network devices---to facilitate joint collection and analysis. Sonata allows operators to more directly express network traffic analysis tasks in terms of a high-level language. The underlying runtime partitions each query into a portion that runs on the switch and another that runs on the streaming analytics platform iteratively refines the query to efficiently capture only the traffic that pertains to the operator's query, and exploits sketches to reduce state in switches in exchange for more approximate results. Through an evaluation of a prototype implementation, we demonstrate that Sonata can support a wide range of network telemetry tasks with less state in the network, and lower data rates to streaming analytics systems, than current approaches can achieve.

  20. Sonata: Query-Driven Network Telemetry

    KAUST Repository

    Gupta, Arpit

    2017-05-02

    Operating networks depends on collecting and analyzing measurement data. Current technologies do not make it easy to do so, typically because they separate data collection (e.g., packet capture or flow monitoring) from analysis, producing either too much data to answer a general question or too little data to answer a detailed question. In this paper, we present Sonata, a network telemetry system that uses a uniform query interface to drive the joint collection and analysis of network traffic. Sonata takes the advantage of two emerging technologies---streaming analytics platforms and programmable network devices---to facilitate joint collection and analysis. Sonata allows operators to more directly express network traffic analysis tasks in terms of a high-level language. The underlying runtime partitions each query into a portion that runs on the switch and another that runs on the streaming analytics platform iteratively refines the query to efficiently capture only the traffic that pertains to the operator\\'s query, and exploits sketches to reduce state in switches in exchange for more approximate results. Through an evaluation of a prototype implementation, we demonstrate that Sonata can support a wide range of network telemetry tasks with less state in the network, and lower data rates to streaming analytics systems, than current approaches can achieve.

  1. Neural Networks

    Directory of Open Access Journals (Sweden)

    Schwindling Jerome

    2010-04-01

    Full Text Available This course presents an overview of the concepts of the neural networks and their aplication in the framework of High energy physics analyses. After a brief introduction on the concept of neural networks, the concept is explained in the frame of neuro-biology, introducing the concept of multi-layer perceptron, learning and their use as data classifer. The concept is then presented in a second part using in more details the mathematical approach focussing on typical use cases faced in particle physics. Finally, the last part presents the best way to use such statistical tools in view of event classifers, putting the emphasis on the setup of the multi-layer perceptron. The full article (15 p. corresponding to this lecture is written in french and is provided in the proceedings of the book SOS 2008.

  2. Quantifying Entrepreneurial Networks: Data Collection in Addis Ababa, Ethiopia

    Science.gov (United States)

    2013-06-10

    to meet with the country manager for Schulze Global Investments (SGI), an emerging markets private equity firm. I had been introduced to Ms...member of the mirt team who has developed an interest in photography into a thriving business focusing on assisting firms with marketing and...bring in revenue. The branding business has now taken off and he has four employees and his clients include Pepsi . I also had the opportunity to eat

  3. Long Reach RFID-over-Fiber Distribution and Collection Network

    DEFF Research Database (Denmark)

    Madsen, Peter; Suhr, Lau Frejstrup; Vegas Olmos, Juan José

    This paper presents an RFID-over-Fiber wireless track and trace system using active RFID tags. This paper demonstrates a system, operating over distances up to 30km of optical fiber and 50m of wireless readability.......This paper presents an RFID-over-Fiber wireless track and trace system using active RFID tags. This paper demonstrates a system, operating over distances up to 30km of optical fiber and 50m of wireless readability....

  4. Network lifetime-aware data collection in Underwater Sensor ...

    Indian Academy of Sciences (India)

    Jalaja Janardanan Kartha

    2017-09-07

    Sep 7, 2017 ... existing models to assess their effectiveness and to investigate the trade-offs. Results show ... coverage drops below a predefined threshold and (vi) connectivity is .... Cost Clustering Protocol (MCCP), Distributed Underwater.

  5. Communication and Networking in Smart Grids

    CERN Document Server

    Xiao, Yang

    2012-01-01

    Appropriate for researchers, practitioners, and students alike, Communication and Networking in Smart Grids presents state-of-the-art approaches and novel technologies for communication networks in smart grids. It explains how contemporary grid networks are developed and deployed and presents a collection of cutting-edge advances to help improve current practice. Prominent researchers working on smart grids and in related fields around the world explain the fundamental aspects and applications of smart grids. Describing the role that communication and networking will play in future smart grids

  6. Revealing networks from dynamics: an introduction

    International Nuclear Information System (INIS)

    Timme, Marc; Casadiego, Jose

    2014-01-01

    What can we learn from the collective dynamics of a complex network about its interaction topology? Taking the perspective from nonlinear dynamics, we briefly review recent progress on how to infer structural connectivity (direct interactions) from accessing the dynamics of the units. Potential applications range from interaction networks in physics, to chemical and metabolic reactions, protein and gene regulatory networks as well as neural circuits in biology and electric power grids or wireless sensor networks in engineering. Moreover, we briefly mention some standard ways of inferring effective or functional connectivity. (topical review)

  7. The First Year of Croatian Meteor Network

    Science.gov (United States)

    Andreic, Zeljko; Segon, Damir

    2010-08-01

    The idea and a short history of Croatian Meteor Network (CMN) is described. Based on use of cheap surveillance cameras, standard PC-TV cards and old PCs, the Network allows schools, amateur societies and individuals to participate in photographic meteor patrol program. The network has a strong educational component and many cameras are located at or around teaching facilities. Data obtained by these cameras are collected and processed by the scientific team of the network. Currently 14 cameras are operable, covering a large part of the croatian sky, data gathering is fully functional, and data reduction software is in testing phase.

  8. NESSIE: Network Example Source Supporting Innovative Experimentation

    Science.gov (United States)

    Taylor, Alan; Higham, Desmond J.

    We describe a new web-based facility that makes available some realistic examples of complex networks. NESSIE (Network Example Source Supporting Innovative Experimentation) currently contains 12 specific networks from a diverse range of application areas, with a Scottish emphasis. This collection of data sets is designed to be useful for researchers in network science who wish to evaluate new algorithms, concepts and models. The data sets are available to download in two formats (MATLAB's .mat format and .txt files readable by packages such as Pajek), and some basic MATLAB tools for computing summary statistics are also provided.

  9. Collective influence in evolutionary social dilemmas

    Science.gov (United States)

    Szolnoki, Attila; Perc, Matjaž

    2016-03-01

    When evolutionary games are contested in structured populations, the degree of each player in the network plays an important role. If they exist, hubs often determine the fate of the population in remarkable ways. Recent research based on optimal percolation in random networks has shown, however, that the degree is neither the sole nor the best predictor of influence in complex networks. Low-degree nodes may also be optimal influencers if they are hierarchically linked to hubs. Taking this into account leads to the formalism of collective influence in complex networks, which as we show here, has far-reaching implications for the favorable resolution of social dilemmas. In particular, there exists an optimal hierarchical depth for the determination of collective influence that we use to describe the potency of players for passing their strategies, which depends on the strength of the social dilemma. Interestingly, the degree, which corresponds to the baseline depth zero, is optimal only when the temptation to defect is small. Our research reveals that evolutionary success stories are related to spreading processes which are rooted in favorable hierarchical structures that extend beyond local neighborhoods.

  10. Feedback Networks

    OpenAIRE

    Zamir, Amir R.; Wu, Te-Lin; Sun, Lin; Shen, William; Malik, Jitendra; Savarese, Silvio

    2016-01-01

    Currently, the most successful learning models in computer vision are based on learning successive representations followed by a decision layer. This is usually actualized through feedforward multilayer neural networks, e.g. ConvNets, where each layer forms one of such successive representations. However, an alternative that can achieve the same goal is a feedback based approach in which the representation is formed in an iterative manner based on a feedback received from previous iteration's...

  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. Networks and centroid metrics for understanding football | Gama ...

    African Journals Online (AJOL)

    This study aimedto verifythe network of contacts resulting from the collective behaviour of professional football teams through the centroid method and networks as well, therebyproviding detailed information about the match to coaches and sport analysts. For this purpose, 999 collective attacking actions from twoteams were ...

  13. An information spreading model based on online social networks

    Science.gov (United States)

    Wang, Tao; He, Juanjuan; Wang, Xiaoxia

    2018-01-01

    Online social platforms are very popular in recent years. In addition to spreading information, users could review or collect information on online social platforms. According to the information spreading rules of online social network, a new information spreading model, namely IRCSS model, is proposed in this paper. It includes sharing mechanism, reviewing mechanism, collecting mechanism and stifling mechanism. Mean-field equations are derived to describe the dynamics of the IRCSS model. Moreover, the steady states of reviewers, collectors and stiflers and the effects of parameters on the peak values of reviewers, collectors and sharers are analyzed. Finally, numerical simulations are performed on different networks. Results show that collecting mechanism and reviewing mechanism, as well as the connectivity of the network, make information travel wider and faster, and compared to WS network and ER network, the speed of reviewing, sharing and collecting information is fastest on BA network.

  14. Modeling the citation network by network cosmology.

    Science.gov (United States)

    Xie, Zheng; Ouyang, Zhenzheng; Zhang, Pengyuan; Yi, Dongyun; Kong, Dexing

    2015-01-01

    Citation between papers can be treated as a causal relationship. In addition, some citation networks have a number of similarities to the causal networks in network cosmology, e.g., the similar in-and out-degree distributions. Hence, it is possible to model the citation network using network cosmology. The casual network models built on homogenous spacetimes have some restrictions when describing some phenomena in citation networks, e.g., the hot papers receive more citations than other simultaneously published papers. We propose an inhomogenous causal network model to model the citation network, the connection mechanism of which well expresses some features of citation. The node growth trend and degree distributions of the generated networks also fit those of some citation networks well.

  15. Random catalytic reaction networks

    Science.gov (United States)

    Stadler, Peter F.; Fontana, Walter; Miller, John H.

    1993-03-01

    We study networks that are a generalization of replicator (or Lotka-Volterra) equations. They model the dynamics of a population of object types whose binary interactions determine the specific type of interaction product. Such a system always reduces its dimension to a subset that contains production pathways for all of its members. The network equation can be rewritten at a level of collectives in terms of two basic interaction patterns: replicator sets and cyclic transformation pathways among sets. Although the system contains well-known cases that exhibit very complicated dynamics, the generic behavior of randomly generated systems is found (numerically) to be extremely robust: convergence to a globally stable rest point. It is easy to tailor networks that display replicator interactions where the replicators are entire self-sustaining subsystems, rather than structureless units. A numerical scan of random systems highlights the special properties of elementary replicators: they reduce the effective interconnectedness of the system, resulting in enhanced competition, and strong correlations between the concentrations.

  16. Neural network classifier of attacks in IP telephony

    Science.gov (United States)

    Safarik, Jakub; Voznak, Miroslav; Mehic, Miralem; Partila, Pavol; Mikulec, Martin

    2014-05-01

    Various types of monitoring mechanism allow us to detect and monitor behavior of attackers in VoIP networks. Analysis of detected malicious traffic is crucial for further investigation and hardening the network. This analysis is typically based on statistical methods and the article brings a solution based on neural network. The proposed algorithm is used as a classifier of attacks in a distributed monitoring network of independent honeypot probes. Information about attacks on these honeypots is collected on a centralized server and then classified. This classification is based on different mechanisms. One of them is based on the multilayer perceptron neural network. The article describes inner structure of used neural network and also information about implementation of this network. The learning set for this neural network is based on real attack data collected from IP telephony honeypot called Dionaea. We prepare the learning set from real attack data after collecting, cleaning and aggregation of this information. After proper learning is the neural network capable to classify 6 types of most commonly used VoIP attacks. Using neural network classifier brings more accurate attack classification in a distributed system of honeypots. With this approach is possible to detect malicious behavior in a different part of networks, which are logically or geographically divided and use the information from one network to harden security in other networks. Centralized server for distributed set of nodes serves not only as a collector and classifier of attack data, but also as a mechanism for generating a precaution steps against attacks.

  17. Synchronized Data Aggregation for Wireless Sensor Network

    DEFF Research Database (Denmark)

    Dnyaneshwar, Mantri; Prasad, Neeli R.; Prasad, Ramjee

    2014-01-01

    Wireless Sensor Networks (WSNs) are used for monitoring and data collection purposes. A key challenge in effective data collection is to schedule and synchronize the activities of the nodes with global clock. This paper proposes the Synchronized Data Aggregation Algorithm (SDA) using spanning tree...

  18. Efficient Immutable Collections

    NARCIS (Netherlands)

    Steindorfer, M.J.

    2017-01-01

    This thesis proposes novel and efficient data structures, suitable for immutable collection libraries, that carefully balance memory footprint and runtime performance of operations, and are aware of constraints and platform co-design challenges on the Java Virtual Machine (JVM). Collection data

  19. Profiling a Periodicals Collection

    Science.gov (United States)

    Bolgiano, Christina E.; King, Mary Kathryn

    1978-01-01

    Libraries need solid information upon which to base collection development decisions. Specific evaluative methods for determining scope, access, and usefullness are described. Approaches used for data collection include analysis of interlibrary loan requests, comparison with major bibliographies, and analysis of accessibility through available…

  20. Preparing collections for digitization

    CERN Document Server

    Bulow, Anna E

    2010-01-01

    Most libraries, archives and museums are confronting the challenges of providing digital access to their collections. This guide offers guidance covering the end-to-end process of digitizing collections, from selecting records for digitization to choosing suppliers and equipment and dealing with documents that present individual problems.

  1. High Collection Nonimaging Optics

    Science.gov (United States)

    Winston, Roland

    1989-07-01

    Nonimaging optics departs from the methods of traditional optical design to develop instead techniques for maximizing the collecting power of concentrating elements and systems. Designs which exceed the concentration attainable with focusing techniques by factors of four or more and approach the theoretical limit are possible (ideal concentrators). The methodology for designing high collection nonirnaging systems is described.

  2. Collective Responsibility for Oppression

    NARCIS (Netherlands)

    Stahl, Titus

    2017-01-01

    Many contemporary forms of oppression are not primarily the result of formally organized collective action nor are they an unintended outcome of a combination of individual actions. This raises the question of collective responsibility. I argue that we can only determine who is responsible for

  3. Bloody Fast Blood Collection

    NARCIS (Netherlands)

    van Brummelen, Samuel Pieter Josephus

    2017-01-01

    This thesis consists of four parts: The first part contains an introduction, the second presents approaches for the evaluation of waiting times at blood collection sites, the third uses these to present approaches that improve waiting times at blood collection sites. The final part shows the

  4. UNO's Afghanistan Collection.

    Science.gov (United States)

    McKernan, M. D.

    This paper explores the background history and sources of the Afghanistan collection at the University Library, University of Nebraska at Omaha (UNO). Credit for the impetus behind the development of the collection is given to Chris Jung, a former UNO geography/geology faculty member; Ronald Roskens, then UNO chancellor; and the Afghanistan…

  5. Instructions for collecting Bamboos

    NARCIS (Netherlands)

    Corner, E.J.H.

    1962-01-01

    Although our knowledge of reproductive parts of bamboos is still very defective, an adequately collected vegetative specimen is valuable and sufficient for identification. Like in tree ferns (see p. 567) and in rattans, a well-collected specimen does not need to be excessively bulky, provided the

  6. Botanical Collections of Brass

    NARCIS (Netherlands)

    Brass, L.J.

    1966-01-01

    Earliest collections, made in southeastern parts of Queensland, were not numbered in sequence, and probably no duplicates were kept. Serious collecting began in 1919, when a start was made in sending specimens to C.T. White at the Queensland Herbarium.

  7. Action Research as a Network

    DEFF Research Database (Denmark)

    Boulus-Rødje, Nina

    2012-01-01

    This paper explores roles and interventions in IS action research. I draw upon a four-year research project about electronic medical records, conducted in close collaboration with a community partner. Following a self-reflexive stance, I trace the trajectory of the research engagement...... and the different roles I occupied. To better understand the complex nature of collaboration found within action research projects, I propose conceptualizing action research as a network. The network framework directs our attention to the collective production and the conditions through which roles...... this influences the researcher’s agency....

  8. Networking activism: implications for Greece

    Directory of Open Access Journals (Sweden)

    Pantelis Vatikiotis

    2011-12-01

    Full Text Available The outbreak of December 2008 against police brutality through a wave of demonstrations and street protests in Athens, which was strongly advocated by protest activities and practices across the world, addresses several issues in relation to the transformative potentials of mediated collective action. The paper critically evaluates different accounts of December events, probing then into thevery networking of that movement. From this perspective, it points out another aspect of the local-global interplay in protest culture along new mediating practices (beyond the creation of transnational publics, that of the implications of transnational networking for local social activism and identification, addressing relevant questions in the Greek context.

  9. Networked innovations in guided tours

    DEFF Research Database (Denmark)

    Meged, Jane Widtfeldt; Zillinger, Malin

    This presentation is about a case study being done on networked innovation that is taking place within the scene of free guided tours in Copenhagen. Data has been collected on interactions between actors within the network of peers. In this way, both the own organisation and the actual market...... is being continually developed. ICT plays a key role, just as well as the relationships between the individual actors. It has been shown that close relationships building on friendship and trust are beneficial for the process of innovation. The fast growth of the sector of free guided tours however poses...

  10. Network bursts in cortical neuronal cultures: 'noise - versus pacemaker'- driven neural network simulations

    NARCIS (Netherlands)

    Gritsun, T.; Stegenga, J.; le Feber, Jakob; Rutten, Wim

    2009-01-01

    In this paper we address the issue of spontaneous bursting activity in cortical neuronal cultures and explain what might cause this collective behavior using computer simulations of two different neural network models. While the common approach to acivate a passive network is done by introducing

  11. Green mobile networks a networking perspective

    CERN Document Server

    Ansari, Nirwan

    2016-01-01

    Combines the hot topics of energy efficiency and next generation mobile networking, examining techniques and solutions. Green communications is a very hot topic. Ever increasing mobile network bandwidth rates significantly impacts on operating costs due to aggregate network energy consumption. As such, design on 4G networks and beyond has increasingly started to focus on 'energy efficiency' or so-called 'green' networks. Many techniques and solutions have been proposed to enhance the energy efficiency of mobile networks, yet no book has provided an in-depth analysis of the energy consumption issues in mobile networks nor offers detailed theories, tools and solutions for solving the energy efficiency problems.

  12. Social Networks and Sales Performance

    Directory of Open Access Journals (Sweden)

    Danny Pimentel Claro

    2011-05-01

    Full Text Available This paper argues that an informal network can itself be a basis for the increase in a sales manager’s performance. Informal networks create a structure that surpasses the formal hierarchical structure defined by the firm. We concentrated on the advice network and considered two different views of network structure that claim to have impact on performance. To explore this claim, we examined whether sales managers develop either a highly cohesive network structure (i.e. Coleman’s view or one containing structural holes (i.e. Burt’s view in order to achieve higher sales. We also investigated the matter of tie strength put forward by Granovetter in his seminal 1973 work. Census data was collected from about 500 personnel from an agricultural input retailer having 23 divisions. Estimates from a sample of 101 sales managers showed the importance of a highly cohesive structure (degree centrality for the three measures of sales manager’s performance. The strong ties have a positive impact on performance, suggesting the importance of building up strong bonds with network contacts. Sales managers’ age, time within the retailer and education also influence performance. These results imply that firms should stimulate contacts among personnel to spread technical and commercial information.

  13. Collaborative Trust Networks in Engineering Design Adaptation

    DEFF Research Database (Denmark)

    Atkinson, Simon Reay; Maier, Anja; Caldwell, Nicholas

    2011-01-01

    ); applying the Change Prediction Method (CPM) tool. It posits the idea of the ‘Networks-in-Being’ with varying individual and collective characteristics. [Social] networks are considered to facilitate information exchange between actors. At the same time, networks failing to provide trusted-information can...... hinder effective communication and collaboration. Different combinations of trust may therefore improve or impair the likelihood of information flow, transfer and subsequent action (cause and effect). This paper investigates how analysing different types of network-structures-in-being can support......Within organisations, decision makers have to rely on collaboration with other actors from different disciplines working within highly dynamic and distributed associated networks of varying size and scales. This paper develops control and influence networks within Design Structure Matrices (DSM...

  14. Complex network synchronization of chaotic systems with delay coupling

    International Nuclear Information System (INIS)

    Theesar, S. Jeeva Sathya; Ratnavelu, K.

    2014-01-01

    The study of complex networks enables us to understand the collective behavior of the interconnected elements and provides vast real time applications from biology to laser dynamics. In this paper, synchronization of complex network of chaotic systems has been studied. Every identical node in the complex network is assumed to be in Lur’e system form. In particular, delayed coupling has been assumed along with identical sector bounded nonlinear systems which are interconnected over network topology

  15. Sync in Complex Dynamical Networks: Stability, Evolution, Control, and Application

    OpenAIRE

    Li, Xiang

    2005-01-01

    In the past few years, the discoveries of small-world and scale-free properties of many natural and artificial complex networks have stimulated significant advances in better understanding the relationship between the topology and the collective dynamics of complex networks. This paper reports recent progresses in the literature of synchronization of complex dynamical networks including stability criteria, network synchronizability and uniform synchronous criticality in different topologies, ...

  16. Predicting and controlling infectious disease epidemics using temporal networks.

    Science.gov (United States)

    Masuda, Naoki; Holme, Petter

    2013-01-01

    Infectious diseases can be considered to spread over social networks of people or animals. Mainly owing to the development of data recording and analysis techniques, an increasing amount of social contact data with time stamps has been collected in the last decade. Such temporal data capture the dynamics of social networks on a timescale relevant to epidemic spreading and can potentially lead to better ways to analyze, forecast, and prevent epidemics. However, they also call for extended analysis tools for network epidemiology, which has, to date, mostly viewed networks as static entities. We review recent results of network epidemiology for such temporal network data and discuss future developments.

  17. Review of Biological Network Data and Its Applications

    Directory of Open Access Journals (Sweden)

    Donghyeon Yu

    2013-12-01

    Full Text Available Studying biological networks, such as protein-protein interactions, is key to understanding complex biological activities. Various types of large-scale biological datasets have been collected and analyzed with high-throughput technologies, including DNA microarray, next-generation sequencing, and the two-hybrid screening system, for this purpose. In this review, we focus on network-based approaches that help in understanding biological systems and identifying biological functions. Accordingly, this paper covers two major topics in network biology: reconstruction of gene regulatory networks and network-based applications, including protein function prediction, disease gene prioritization, and network-based genome-wide association study.

  18. ENLIGHT Network

    CERN Multimedia

    Ballantine, A; Dixon-Altaber, H; Dosanjh, M; Kuchina, L

    2011-01-01

    State-of-the-art techniques borrowed from particle accelerators and detectors are a key element in hadrontherapy and several European projects are actively fostering the collaboration amongst the various disciplines and countries. ENLIGHT was established in 2002 to coordinate these European efforts in hadron therapy. The ENLIGHT network is formed by the European hadrontherapy Community, with more than 300 participants from twenty European countries. A major achievement of ENLIGHT has been the blending of traditionally separate communities so that clinicians, physicists, biologists and engineers with experience and interest in particle therapy are working together.

  19. Improving network management with Software Defined Networking

    International Nuclear Information System (INIS)

    Dzhunev, Pavel

    2013-01-01

    Software-defined networking (SDN) is developed as an alternative to closed networks in centers for data processing by providing a means to separate the control layer data layer switches, and routers. SDN introduces new possibilities for network management and configuration methods. In this article, we identify problems with the current state-of-the-art network configuration and management mechanisms and introduce mechanisms to improve various aspects of network management

  20. Chronopolis Digital Preservation Network

    Directory of Open Access Journals (Sweden)

    David Minor

    2010-07-01

    Full Text Available The Chronopolis Digital Preservation Initiative, one of the Library of Congress’ latest efforts to collect and preserve at-risk digital information, has completed its first year of service as a multi-member partnership to meet the archival needs of a wide range of domains.Chronopolis is a digital preservation data grid framework developed by the San Diego Supercomputer Center (SDSC at UC San Diego, the UC San Diego Libraries (UCSDL, and their partners at the National Center for Atmospheric Research (NCAR in Colorado and the University of Maryland's Institute for Advanced Computer Studies (UMIACS.Chronopolis addresses a critical problem by providing a comprehensive model for the cyberinfrastructure of collection management, in which preserved intellectual capital is easily accessible, and research results, education material, and new knowledge can be incorporated smoothly over the long term. Integrating digital library, data grid, and persistent archive technologies, Chronopolis has created trusted environments that span academic institutions and research projects, with the goal of long-term digital preservation.A key goal of the Chronopolis project is to provide cross-domain collection sharing for long-term preservation. Using existing high-speed educational and research networks and mass-scale storage infrastructure investments, the partnership is leveraging the data storage capabilities at SDSC, NCAR, and UMIACS to provide a preservation data grid that emphasizes heterogeneous and highly redundant data storage systems.In this paper we will explore the major themes within Chronopolis, including:a The philosophy and theory behind a nationally federated data grid for preservation. b The core tools and technologies used in Chronopolis. c The metadata schema that is being developed within Chronopolis for all of the data elements. d Lessons learned from the first year of the project.e Next steps in digital preservation using Chronopolis: how we

  1. Microalgal Culture Collection Transfers

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Milford Microalgal culture Collection holds over 200 live cultures representing 13 classes of of algae. The cultures are maintained in three different growing...

  2. Third Party Collection Program

    National Research Council Canada - National Science Library

    Young, Shelton

    1993-01-01

    United States Code, title 10, sec. 1095, allows DoD to collect from health insurance plans reasonable inpatient hospital costs incurred on behalf of insured military retirees and military dependants...

  3. Freedom and the Collective

    Directory of Open Access Journals (Sweden)

    Straume, Ingerid S.

    2008-12-01

    Full Text Available Since Isaiah Berlin’s epitomizing Cold War-essay, "Two Concepts of Liberty, " thinkers who emphasize collective concepts of social life have carried the burden of proof against charges of totalitarian tendencies. The background is a ground figure in contemporary political thought that sets notions of collectivity against individual freedom, in a zero sum game: Either one is in favour of the individual, or one is in favour of the collective, and hence, so the bias has it, willing to sacrifice the rights and liberties of individuals. Since it is impossible to favour the latter position and remain liberal, in the wide sense of the term, this dichotomy serves to rob contemporary political thought of both its classical and revolutionary connotations, leaving only individual initiatives like lobbying and voting. Cornelius Castoriadis offers a way around this – arguably false – dichotomy, by regarding individual and collective freedom as two sides of the same coin.

  4. Online Data Collection.

    Science.gov (United States)

    Topp, Neal W.; Pawloski, Bob

    2002-01-01

    Describes the eventful history of online data collection and presents a review of current literature following by a list of pros and cons to be considered when stepping into online surveying. (Contains 14 references.) (Author/YDS)

  5. Long-term collections

    CERN Multimedia

    Collectes à long terme

    2007-01-01

    The Committee of the Long Term Collections (CLT) asks for your attention for the following message from a young Peruvian scientist, following the earthquake which devastated part of her country a month ago.

  6. Turtle Photograph Collection

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Photos collected in marine turtle research programs are diverse, ranging from isolated observations of incidental encounters with turtles on the high-seas to...

  7. Glacier Photograph Collection

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Glacier Photograph Collection is a database of photographs of glaciers from around the world, some dating back to the mid-1850's, that provide an historical...

  8. NOS Hydrographic Surveys Collection

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The National Oceanic and Atmospheric Administration (NOAA) has the statutory mandate to collect hydrographic data in support of nautical chart compilation for safe...

  9. Shared collections collaborative stewardship

    CERN Document Server

    Hale, Dawn

    2016-01-01

    With practical advice on issues such as governance and business models, demand driven acquisition, rare works, and access, this monograph is a valuable resource for academic library directors, administrators, and collection development leaders.

  10. NLM Digital Collections

    Data.gov (United States)

    U.S. Department of Health & Human Services — The National Library of Medicine's (NLM) Digital Collections offers a search-based Web service that provides access to the Dublin Core metadata and full-text OCR of...

  11. 75 FR 66165 - Information Collection Activities: Proposed Collection; Comment Request

    Science.gov (United States)

    2010-10-27

    ... additional information should be collected to further the aims of government transparency. DATES: Comments... OFFICE OF MANAGEMENT AND BUDGET Information Collection Activities: Proposed Collection; Comment... are warranted. We are particularly interested in comments on whether the information collected in the...

  12. Inference on network statistics by restricting to the network space: applications to sexual history data.

    Science.gov (United States)

    Goyal, Ravi; De Gruttola, Victor

    2018-01-30

    Analysis of sexual history data intended to describe sexual networks presents many challenges arising from the fact that most surveys collect information on only a very small fraction of the population of interest. In addition, partners are rarely identified and responses are subject to reporting biases. Typically, each network statistic of interest, such as mean number of sexual partners for men or women, is estimated independently of other network statistics. There is, however, a complex relationship among networks statistics; and knowledge of these relationships can aid in addressing concerns mentioned earlier. We develop a novel method that constrains a posterior predictive distribution of a collection of network statistics in order to leverage the relationships among network statistics in making inference about network properties of interest. The method ensures that inference on network properties is compatible with an actual network. Through extensive simulation studies, we also demonstrate that use of this method can improve estimates in settings where there is uncertainty that arises both from sampling and from systematic reporting bias compared with currently available approaches to estimation. To illustrate the method, we apply it to estimate network statistics using data from the Chicago Health and Social Life Survey. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

  13. Design principles in biological networks

    Science.gov (United States)

    Goyal, Sidhartha

    Much of biology emerges from networks of interactions. Even in a single bacterium such as Escherichia coli, there are hundreds of coexisting gene and protein networks. Although biological networks are the outcome of evolution, various physical and biological constraints limit their functional capacity. The focus of this thesis is to understand how functional constraints such as optimal growth in mircoorganisms and information flow in signaling pathways shape the metabolic network of bacterium E. coli and the quorum sensing network of marine bacterium Vibrio harveyi, respectively. Metabolic networks convert basic elemental sources into complex building-blocks eventually leading to cell's growth. Therefore, typically, metabolic pathways are often coupled both by the use of a common substrate and by stoichiometric utilization of their products for cell growth. We showed that such a coupled network with product-feedback inhibition may exhibit limit-cycle oscillations which arise via a Hopf bifurcation. Furthermore, we analyzed several representative metabolic modules and find that, in all cases, simple product-feedback inhibition allows nearly optimal growth, in agreement with the predicted growth-rate by the flux-balance analysis (FBA). Bacteria have fascinating and diverse social lives. They display coordinated group behaviors regulated by quorum sensing (QS) systems. The QS circuit of V. harveyi integrates and funnels different ecological information through a common phosphorelay cascade to a set of small regulatory RNAs (sRNAs) that enables collective behavior. We analyzed the signaling properties and information flow in the QS circuit, which provides a model for information flow in signaling networks more generally. A comparative study of post-transcriptional and conventional transcriptional regulation suggest a niche for sRNAs in allowing cells to transition quickly yet reliably between distinct states. Furthermore, we develop a new framework for analyzing signal

  14. Rehabilitating the Stroke Collection

    Directory of Open Access Journals (Sweden)

    Mary Grimmond

    2006-06-01

    Full Text Available Objective The aim of this project was to complete an analysis of monograph and audiovisual items held in the Central Coast Health Service (CCHS Libraries and containing information relevant to the treatment of acute stroke. Acute stroke is treated by multidisciplinary teams of clinicians based at two hospitals within the CCHS. The adequacy of the library collection was measured by subject coverage and age. Methods The methodology used consisted of three main steps: a literature review; design, administration, and analysis of a questionnaire to members of the CCHS Acute Stroke Team; and an analysis of the libraries’ collections. The research project utilised project management methodology and an evidence based librarianship framework. Results The questionnaire revealed that electronic resources were by far the most frequently used by participants, followed in order by print journals, books, interlibrary loan articles, and audiovisual items. Collection analysis demonstrated that the monograph and audiovisual collections were adequate in both scope and currency to support the information needs of Acute Stroke Team members, with the exception of resources to support patient education. Conclusion The researchers developed recommendations for future collection development in the area of acute stroke resources. Conducting this project within the evidence based librarianship framework helped to develop library staff members’ confidence in their ability to make future collection development decisions, informed by the target group’s information needs and preferences. The collection analysis methodology was designed to be replicated, and new specialist groups within the client base of the library will be targeted to repeat the collection analysis process.

  15. Collective excitations in nuclei

    International Nuclear Information System (INIS)

    Chomaz, Ph.

    1998-01-01

    The properties of the nucleus cannot be reduced to the properties of its constituents: it is a complex system. The fact that many properties of the nucleus are consequences of the existence of mean-field potential is a manifestation of this complexity. In particular, the nucleons can thus self-organize in collective motions such as giant resonances. Therefore the study of this collective motions is a very good tool to understand the properties of the nucleus itself. The purpose of this article is to stress some aspects of these collective vibrations. We have studied how an ensemble of fermions as the nucleus can self-organize in collective vibrations which are behaving like a gas of bosons in weak interaction. Understanding of these phenomena remains one of the important subjects of actuality in the context of quantal systems in strong interaction. In particular, the study of the states with one or two vibration quanta provides a direct information on the structure of nuclei close to their ground states. Moreover, some collective states appear to be very robust against the onset of chaos. This is the case of the hot giant dipole built on top of a hot nucleus which seems to survive up to rather high temperatures. Their sudden disappearance is still a subject of controversy. It may be that the mean-field and the associated collective states are playing a crucial role also in catastrophic processes such as the phase-transitions. Indeed, when the system is diluted the collective vibrations may become unstable and it seems that these unstable modes provide a natural explanation to the self organization of the system in drops. Finally, considering the diversity of the different structures of exotic nuclei one may expect new vibration types. All these studies are showing the diversity of the collective motions of strongly correlated quantum systems such as the nucleus but many open questions remain to be solved. (authors)

  16. Collective excitations in nuclei

    Energy Technology Data Exchange (ETDEWEB)

    Chomaz, Ph. [Grand Accelerateur National d`Ions Lourds (GANIL), 14 - Caen (France); Collaboration: La Direction des Sciences de la Matiere du CEA (FR); Le Fonds National de la Recherche Scientifique de Belgique (BE)

    1998-12-31

    The properties of the nucleus cannot be reduced to the properties of its constituents: it is a complex system. The fact that many properties of the nucleus are consequences of the existence of mean-field potential is a manifestation of this complexity. In particular, the nucleons can thus self-organize in collective motions such as giant resonances. Therefore the study of this collective motions is a very good tool to understand the properties of the nucleus itself. The purpose of this article is to stress some aspects of these collective vibrations. We have studied how an ensemble of fermions as the nucleus can self-organize in collective vibrations which are behaving like a gas of bosons in weak interaction. Understanding of these phenomena remains one of the important subjects of actuality in the context of quantal systems in strong interaction. In particular, the study of the states with one or two vibration quanta provides a direct information on the structure of nuclei close to their ground states. Moreover, some collective states appear to be very robust against the onset of chaos. This is the case of the hot giant dipole built on top of a hot nucleus which seems to survive up to rather high temperatures. Their sudden disappearance is still a subject of controversy. It may be that the mean-field and the associated collective states are playing a crucial role also in catastrophic processes such as the phase-transitions. Indeed, when the system is diluted the collective vibrations may become unstable and it seems that these unstable modes provide a natural explanation to the self organization of the system in drops. Finally, considering the diversity of the different structures of exotic nuclei one may expect new vibration types. All these studies are showing the diversity of the collective motions of strongly correlated quantum systems such as the nucleus but many open questions remain to be solved. (authors) 304 refs., 53 figs., 5 tabs.

  17. Collective field accelerator

    International Nuclear Information System (INIS)

    Luce, J.S.

    1978-01-01

    A collective field accelerator which operates with a vacuum diode and utilizes a grooved cathode and a dielectric anode that operates with a relativistic electron beam with a ν/γ of approx. 1, and a plurality of dielectric lenses having an axial magnetic field thereabout to focus the collectively accelerated electrons and ions which are ejected from the anode. The anode and lenses operate as unoptimized r-f cavities which modulate and focus the beam

  18. Sparse matrix test collections

    Energy Technology Data Exchange (ETDEWEB)

    Duff, I.

    1996-12-31

    This workshop will discuss plans for coordinating and developing sets of test matrices for the comparison and testing of sparse linear algebra software. We will talk of plans for the next release (Release 2) of the Harwell-Boeing Collection and recent work on improving the accessibility of this Collection and others through the World Wide Web. There will only be three talks of about 15 to 20 minutes followed by a discussion from the floor.

  19. Connecting the Dots and Nodes: A Survey of Skills Requested by Employers for Network Administrators

    Science.gov (United States)

    Morris, Gerard; Fustos, Janos; Haga, Wayne

    2018-01-01

    One definition of a network administrator describes a person who works with computer infrastructures with an emphasis on networking. To determine the specific skills required of a network administrator by employers, data was collected from 698 nationwide job advertisements on Dice.com. The data collection focused on technical skills rather than…

  20. Theory of collective Hamiltonian

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Qingying

    1982-02-01

    Starting from the cranking model, we derive the nuclear collective Hamiltonian. We expand the total energy of the collective motion of the ground state of even--even nuclei in powers of the deformation parameter ..beta... In the first approximation, we only take the lowest-order non-vanished terms in the expansion. The collective Hamiltonian thus obtained rather differs from the A. Bohr's Hamiltonian obtained by the irrotational incompressible liquid drop model. If we neglect the coupling term between ..beta..-and ..gamma..-vibration, our Hamiltonian then has the same form as that of A. Bohr. But there is a difference between these collective parameters. Our collective parameters are determined by the state of motion of the nucleous in the nuclei. They are the microscopic expressions. On the contrary, A. Bohr's collective parameters are only the simple functions of the microscopic physical quantities (such as nuclear radius and surface tension, etc.), and independent of the state of motion of the nucleons in the nuclei. Furthermore, there exist the coupling term between ..beta..-and ..gamma..-vibration and the higher-order terms in our expansion. They can be treated as the perturbations. There are no such terms in A. Bohr's Hamiltonian. These perturbation terms will influence the rotational, vibrational spectra and the ..gamma..-transition process, etc.

  1. Hybrid architecture for building secure sensor networks

    Science.gov (United States)

    Owens, Ken R., Jr.; Watkins, Steve E.

    2012-04-01

    Sensor networks have various communication and security architectural concerns. Three approaches are defined to address these concerns for sensor networks. The first area is the utilization of new computing architectures that leverage embedded virtualization software on the sensor. Deploying a small, embedded virtualization operating system on the sensor nodes that is designed to communicate to low-cost cloud computing infrastructure in the network is the foundation to delivering low-cost, secure sensor networks. The second area focuses on securing the sensor. Sensor security components include developing an identification scheme, and leveraging authentication algorithms and protocols that address security assurance within the physical, communication network, and application layers. This function will primarily be accomplished through encrypting the communication channel and integrating sensor network firewall and intrusion detection/prevention components to the sensor network architecture. Hence, sensor networks will be able to maintain high levels of security. The third area addresses the real-time and high priority nature of the data that sensor networks collect. This function requires that a quality-of-service (QoS) definition and algorithm be developed for delivering the right data at the right time. A hybrid architecture is proposed that combines software and hardware features to handle network traffic with diverse QoS requirements.

  2. Evolutionary games on multilayer networks: a colloquium

    Science.gov (United States)

    Wang, Zhen; Wang, Lin; Szolnoki, Attila; Perc, Matjaž

    2015-05-01

    Networks form the backbone of many complex systems, ranging from the Internet to human societies. Accordingly, not only is the range of our interactions limited and thus best described and modeled by networks, it is also a fact that the networks that are an integral part of such models are often interdependent or even interconnected. Networks of networks or multilayer networks are therefore a more apt description of social systems. This colloquium is devoted to evolutionary games on multilayer networks, and in particular to the evolution of cooperation as one of the main pillars of modern human societies. We first give an overview of the most significant conceptual differences between single-layer and multilayer networks, and we provide basic definitions and a classification of the most commonly used terms. Subsequently, we review fascinating and counterintuitive evolutionary outcomes that emerge due to different types of interdependencies between otherwise independent populations. The focus is on coupling through the utilities of players, through the flow of information, as well as through the popularity of different strategies on different network layers. The colloquium highlights the importance of pattern formation and collective behavior for the promotion of cooperation under adverse conditions, as well as the synergies between network science and evolutionary game theory.

  3. Sampling of temporal networks: Methods and biases

    Science.gov (United States)

    Rocha, Luis E. C.; Masuda, Naoki; Holme, Petter

    2017-11-01

    Temporal networks have been increasingly used to model a diversity of systems that evolve in time; for example, human contact structures over which dynamic processes such as epidemics take place. A fundamental aspect of real-life networks is that they are sampled within temporal and spatial frames. Furthermore, one might wish to subsample networks to reduce their size for better visualization or to perform computationally intensive simulations. The sampling method may affect the network structure and thus caution is necessary to generalize results based on samples. In this paper, we study four sampling strategies applied to a variety of real-life temporal networks. We quantify the biases generated by each sampling strategy on a number of relevant statistics such as link activity, temporal paths and epidemic spread. We find that some biases are common in a variety of networks and statistics, but one strategy, uniform sampling of nodes, shows improved performance in most scenarios. Given the particularities of temporal network data and the variety of network structures, we recommend that the choice of sampling methods be problem oriented to minimize the potential biases for the specific research questions on hand. Our results help researchers to better design network data collection protocols and to understand the limitations of sampled temporal network data.

  4. Fishing out collective memory of migratory schools

    DEFF Research Database (Denmark)

    De Luca, G.; Mariani, Patrizio; MacKenzie, Brian

    2014-01-01

    Animals form groups for many reasons but there are costs and benefit associated with group formation. One of the benefits is collective memory. In groups on the move, social interactions play a crucial role in the cohesion and the ability to make consensus decisions. When migrating from spawning...... to feeding areas fish schools need to retain a collective memory of the destination site over thousand of kilometers and changes in group formation or individual preference can produce sudden changes in migration pathways. We propose a modelling framework, based on stochastic adaptive networks, that can...... reproduce this collective behaviour. We assume that three factors control group formation and school migration behaviour: the intensity of social interaction, the relative number of informed individuals and the preference that each individual has for the particular migration area. We treat these factors...

  5. Approximate Sensory Data Collection: A Survey.

    Science.gov (United States)

    Cheng, Siyao; Cai, Zhipeng; Li, Jianzhong

    2017-03-10

    With the rapid development of the Internet of Things (IoTs), wireless sensor networks (WSNs) and related techniques, the amount of sensory data manifests an explosive growth. In some applications of IoTs and WSNs, the size of sensory data has already exceeded several petabytes annually, which brings too many troubles and challenges for the data collection, which is a primary operation in IoTs and WSNs. Since the exact data collection is not affordable for many WSN and IoT systems due to the limitations on bandwidth and energy, many approximate data collection algorithms have been proposed in the last decade. This survey reviews the state of the art of approximatedatacollectionalgorithms. Weclassifythemintothreecategories: themodel-basedones, the compressive sensing based ones, and the query-driven ones. For each category of algorithms, the advantages and disadvantages are elaborated, some challenges and unsolved problems are pointed out, and the research prospects are forecasted.

  6. Approximate Sensory Data Collection: A Survey

    Directory of Open Access Journals (Sweden)

    Siyao Cheng

    2017-03-01

    Full Text Available With the rapid development of the Internet of Things (IoTs, wireless sensor networks (WSNs and related techniques, the amount of sensory data manifests an explosive growth. In some applications of IoTs and WSNs, the size of sensory data has already exceeded several petabytes annually, which brings too many troubles and challenges for the data collection, which is a primary operation in IoTs and WSNs. Since the exact data collection is not affordable for many WSN and IoT systems due to the limitations on bandwidth and energy, many approximate data collection algorithms have been proposed in the last decade. This survey reviews the state of the art of approximatedatacollectionalgorithms. Weclassifythemintothreecategories: themodel-basedones, the compressive sensing based ones, and the query-driven ones. For each category of algorithms, the advantages and disadvantages are elaborated, some challenges and unsolved problems are pointed out, and the research prospects are forecasted.

  7. Broadcasting collective operation contributions throughout a parallel computer

    Science.gov (United States)

    Faraj, Ahmad [Rochester, MN

    2012-02-21

    Methods, systems, and products are disclosed for broadcasting collective operation contributions throughout a parallel computer. The parallel computer includes a plurality of compute nodes connected together through a data communications network. Each compute node has a plurality of processors for use in collective parallel operations on the parallel computer. Broadcasting collective operation contributions throughout a parallel computer according to embodiments of the present invention includes: transmitting, by each processor on each compute node, that processor's collective operation contribution to the other processors on that compute node using intra-node communications; and transmitting on a designated network link, by each processor on each compute node according to a serial processor transmission sequence, that processor's collective operation contribution to the other processors on the other compute nodes using inter-node communications.

  8. Network performance and fault analytics for LTE wireless service providers

    CERN Document Server

    Kakadia, Deepak; Gilgur, Alexander

    2017-01-01

     This book is intended to describe how to leverage emerging technologies big data analytics and SDN, to address challenges specific to LTE and IP network performance and fault management data in order to more efficiently manage and operate an LTE wireless networks. The proposed integrated solutions permit the LTE network service provider to operate entire integrated network, from RAN to Core , from UE to application service, as one unified system and correspondingly collect and align disparate key metrics and data, using an integrated and holistic approach to network analysis. The LTE wireless network performance and fault involves the network performance and management of network elements in EUTRAN, EPC and IP transport components, not only as individual components, but also as nuances of inter-working of these components. The key metrics for EUTRAN include radio access network accessibility, retainability, integrity, availability and mobility. The key metrics for EPC include MME accessibility, mobility and...

  9. Experiment of Wireless Sensor Network to Monitor Field Data

    Directory of Open Access Journals (Sweden)

    Kwang Sik Kim

    2009-08-01

    Full Text Available Recently the mobile wireless network has been drastically enhanced and one of the most efficient ways to realize the ubiquitous network will be to develop the converged network by integrating the mobile wireless network with other IP fixed network like NGN (Next Generation Network. So in this paper the term of the wireless ubiquitous network is used to describe this approach. In this paper, first, the wireless ubiquitous network architecture is described based on IMS which has been standardized by 3GPP (3rd Generation Partnership Program. Next, the field data collection system to match the satellite data using location information is proposed based on the concept of the wireless ubiquitous network architecture. The purpose of the proposed system is to provide more accurate analyzing method with the researchers in the remote sensing area.

  10. Competing dynamic phases of active polymer networks

    Science.gov (United States)

    Freedman, Simon; Banerjee, Shiladitya; Dinner, Aaron R.

    Recent experiments on in-vitro reconstituted assemblies of F-actin, myosin-II motors, and cross-linking proteins show that tuning local network properties can changes the fundamental biomechanical behavior of the system. For example, by varying cross-linker density and actin bundle rigidity, one can switch between contractile networks useful for reshaping cells, polarity sorted networks ideal for directed molecular transport, and frustrated networks with robust structural properties. To efficiently investigate the dynamic phases of actomyosin networks, we developed a coarse grained non-equilibrium molecular dynamics simulation of model semiflexible filaments, molecular motors, and cross-linkers with phenomenologically defined interactions. The simulation's accuracy was verified by benchmarking the mechanical properties of its individual components and collective behavior against experimental results at the molecular and network scales. By adjusting the model's parameters, we can reproduce the qualitative phases observed in experiment and predict the protein characteristics where phase crossovers could occur in collective network dynamics. Our model provides a framework for understanding cells' multiple uses of actomyosin networks and their applicability in materials research. Supported by the Department of Defense (DoD) through the National Defense Science & Engineering Graduate Fellowship (NDSEG) Program.

  11. Quantifying collective attention from tweet stream.

    Directory of Open Access Journals (Sweden)

    Kazutoshi Sasahara

    Full Text Available Online social media are increasingly facilitating our social interactions, thereby making available a massive "digital fossil" of human behavior. Discovering and quantifying distinct patterns using these data is important for studying social behavior, although the rapid time-variant nature and large volumes of these data make this task difficult and challenging. In this study, we focused on the emergence of "collective attention" on Twitter, a popular social networking service. We propose a simple method for detecting and measuring the collective attention evoked by various types of events. This method exploits the fact that tweeting activity exhibits a burst-like increase and an irregular oscillation when a particular real-world event occurs; otherwise, it follows regular circadian rhythms. The difference between regular and irregular states in the tweet stream was measured using the Jensen-Shannon divergence, which corresponds to the intensity of collective attention. We then associated irregular incidents with their corresponding events that attracted the attention and elicited responses from large numbers of people, based on the popularity and the enhancement of key terms in posted messages or "tweets." Next, we demonstrate the effectiveness of this method using a large dataset that contained approximately 490 million Japanese tweets by over 400,000 users, in which we identified 60 cases of collective attentions, including one related to the Tohoku-oki earthquake. "Retweet" networks were also investigated to understand collective attention in terms of social interactions. This simple method provides a retrospective summary of collective attention, thereby contributing to the fundamental understanding of social behavior in the digital era.

  12. The Network Data Handling War: MySQL vs. NfDump

    NARCIS (Netherlands)

    Hofstede, Rick; Hofstede, R.J.; Sperotto, Anna; Fioreze, Tiago; Pras, Aiko

    Network monitoring plays a crucial role in any network management environment. Especially nowadays, with network speed and load constantly increasing, more and more data needs to be collected and efficiently processed. In highly interactive network monitoring systems, a quick response time from

  13. An Intelligent Tool for Activity Data Collection

    Directory of Open Access Journals (Sweden)

    A. M. Jehad Sarkar

    2011-04-01

    Full Text Available Activity recognition systems using simple and ubiquitous sensors require a large variety of real-world sensor data for not only evaluating their performance but also training the systems for better functioning. However, a tremendous amount of effort is required to setup an environment for collecting such data. For example, expertise and resources are needed to design and install the sensors, controllers, network components, and middleware just to perform basic data collections. It is therefore desirable to have a data collection method that is inexpensive, flexible, user-friendly, and capable of providing large and diverse activity datasets. In this paper, we propose an intelligent activity data collection tool which has the ability to provide such datasets inexpensively without physically deploying the testbeds. It can be used as an inexpensive and alternative technique to collect human activity data. The tool provides a set of web interfaces to create a web-based activity data collection environment. It also provides a web-based experience sampling tool to take the user’s activity input. The tool generates an activity log using its activity knowledge and the user-given inputs. The activity knowledge is mined from the web. We have performed two experiments to validate the tool’s performance in producing reliable datasets.

  14. An intelligent tool for activity data collection.

    Science.gov (United States)

    Sarkar, A M Jehad

    2011-01-01

    Activity recognition systems using simple and ubiquitous sensors require a large variety of real-world sensor data for not only evaluating their performance but also training the systems for better functioning. However, a tremendous amount of effort is required to setup an environment for collecting such data. For example, expertise and resources are needed to design and install the sensors, controllers, network components, and middleware just to perform basic data collections. It is therefore desirable to have a data collection method that is inexpensive, flexible, user-friendly, and capable of providing large and diverse activity datasets. In this paper, we propose an intelligent activity data collection tool which has the ability to provide such datasets inexpensively without physically deploying the testbeds. It can be used as an inexpensive and alternative technique to collect human activity data. The tool provides a set of web interfaces to create a web-based activity data collection environment. It also provides a web-based experience sampling tool to take the user's activity input. The tool generates an activity log using its activity knowledge and the user-given inputs. The activity knowledge is mined from the web. We have performed two experiments to validate the tool's performance in producing reliable datasets.

  15. The algebraic collective model

    International Nuclear Information System (INIS)

    Rowe, D.J.; Turner, P.S.

    2005-01-01

    A recently proposed computationally tractable version of the Bohr collective model is developed to the extent that we are now justified in describing it as an algebraic collective model. The model has an SU(1,1)xSO(5) algebraic structure and a continuous set of exactly solvable limits. Moreover, it provides bases for mixed symmetry collective model calculations. However, unlike the standard realization of SU(1,1), used for computing beta wave functions and their matrix elements in a spherical basis, the algebraic collective model makes use of an SU(1,1) algebra that generates wave functions appropriate for deformed nuclei with intrinsic quadrupole moments ranging from zero to any large value. A previous paper focused on the SO(5) wave functions, as SO(5) (hyper-)spherical harmonics, and computation of their matrix elements. This paper gives analytical expressions for the beta matrix elements needed in applications of the model and illustrative results to show the remarkable gain in efficiency that is achieved by using such a basis in collective model calculations for deformed nuclei

  16. Life Cycle Collection Management

    Directory of Open Access Journals (Sweden)

    Helen Shenton

    2003-09-01

    Full Text Available Life cycle collection management is a way of taking a long-term approach to the responsible stewardship of the British Library's collections and is one of the Library's strategic strands. It defines the different stages in a collection item's existence over time. These stages range from selection and acquisitions processing, cataloguing and press marking, through to preventive conservation, storage and retrieval. Life cycle collection management seeks to identify the costs of each stage in order to show the economic interdependencies between the phases over time. It thereby aims to demonstrate the long-term consequences of what the library takes into its collections, by making explicit the financial and other implications of decisions made at the beginning of the life cycle for the next 100 plus years. This paper describes the work over the past year at the British Library on this complex and complicated subject. It presents the emerging findings and suggests how it can be used for practical reasons (by individual curators and selectors and for economic, governance and political purposes. The paper describes the next steps in the project, for example, on a predictive data model. The British Library is seeking to benchmark itself against comparable organisations in this area. It intends to work with others on specific comparison for example, of life cycle costing of electronic and paper journals, as a prelude to eliding digital and 'traditional' formats.

  17. Lossy Data Aggregation with Network Coding in Stand-Alone Wireless Sensor Networks

    DEFF Research Database (Denmark)

    Madsen, Tatiana Kozlova

    2011-01-01

    in chemical plants, etc. Given resource constrained operation of a sensor network where the nodes are battery powered and buffer sizes are limited, efficient methods for in-network data storage abd it subsequent fast and reliable transmission to a gateway is desirable. To save scarse resources and to prolong......This work focuses on a special type of wireless sensor networks (WSNs) that we refer to as a stand alone network. These netwoks operate in harsh and extreme environments where data collection is done only occasionally. Typical examples include habitat monitoring systems, monitoring systems...

  18. Collection for Ecuador

    CERN Multimedia

    Staff Association

    2016-01-01

    After the violent earthquake that caused the death of hundreds of people, and left thousands wounded and homeless in Ecuador, we appeal to your generosity. We are starting a collection today to help the victims, and the funds will be donated to the INEPE Institute in Quito. This organization, known at CERN for many years as it has been supported by the Long Term Collections of the Staff Association, will be responsible for sending the proceeds of the collection directly to the victims in the field. On behalf of the CERN Management and the CERN Staff Association Fabiola Gianotti, Director General, and Alessandro Raimondo, President of the Staff Association =========================== Bank account details for donations: Bank account holder: Staff Association CERN - 1211 GENEVA 23 Account number: 279-HU106832.1 IBAN: CH85 0027 9279 HU10 6832 1 BIC: UBSWCHZH80A Please mention: Ecuador

  19. Curating Virtual Data Collections

    Science.gov (United States)

    Lynnes, Chris; Leon, Amanda; Ramapriyan, Hampapuram; Tsontos, Vardis; Shie, Chung-Lin; Liu, Zhong

    2015-01-01

    NASAs Earth Observing System Data and Information System (EOSDIS) contains a rich set of datasets and related services throughout its many elements. As a result, locating all the EOSDIS data and related resources relevant to particular science theme can be daunting. This is largely because EOSDIS data's organizing principle is affected more by the way they are produced than around the expected end use. Virtual collections oriented around science themes can overcome this by presenting collections of data and related resources that are organized around the user's interest, not around the way the data were produced. Virtual collections consist of annotated web addresses (URLs) that point to data and related resource addresses, thus avoiding the need to copy all of the relevant data to a single place. These URL addresses can be consumed by a variety of clients, ranging from basic URL downloaders (wget, curl) and web browsers to sophisticated data analysis programs such as the Integrated Data Viewer.

  20. Fostering collective intelligence education

    Directory of Open Access Journals (Sweden)

    Jaime Meza

    2016-06-01

    Full Text Available New educational models are necessary to update learning environments to the digitally shared communication and information. Collective intelligence is an emerging field that already has a significant impact in many areas and will have great implications in education, not only from the side of new methodologies but also as a challenge for education. This paper proposes an approach to a collective intelligence model of teaching using Internet to combine two strategies: idea management and real time assessment in the class. A digital tool named Fabricius has been created supporting these two elements to foster the collaboration and engagement of students in the learning process. As a result of the research we propose a list of KPI trying to measure individual and collective performance. We are conscious that this is just a first approach to define which aspects of a class following a course can be qualified and quantified.

  1. Social network models predict movement and connectivity in ecological landscapes

    Science.gov (United States)

    Fletcher, Robert J.; Acevedo, M.A.; Reichert, Brian E.; Pias, Kyle E.; Kitchens, Wiley M.

    2011-01-01

    Network analysis is on the rise across scientific disciplines because of its ability to reveal complex, and often emergent, patterns and dynamics. Nonetheless, a growing concern in network analysis is the use of limited data for constructing networks. This concern is strikingly relevant to ecology and conservation biology, where network analysis is used to infer connectivity across landscapes. In this context, movement among patches is the crucial parameter for interpreting connectivity but because of the difficulty of collecting reliable movement data, most network analysis proceeds with only indirect information on movement across landscapes rather than using observed movement to construct networks. Statistical models developed for social networks provide promising alternatives for landscape network construction because they can leverage limited movement information to predict linkages. Using two mark-recapture datasets on individual movement and connectivity across landscapes, we test whether commonly used network constructions for interpreting connectivity can predict actual linkages and network structure, and we contrast these approaches to social network models. We find that currently applied network constructions for assessing connectivity consistently, and substantially, overpredict actual connectivity, resulting in considerable overestimation of metapopulation lifetime. Furthermore, social network models provide accurate predictions of network structure, and can do so with remarkably limited data on movement. Social network models offer a flexible and powerful way for not only understanding the factors influencing connectivity but also for providing more reliable estimates of connectivity and metapopulation persistence in the face of limited data.

  2. Social network models predict movement and connectivity in ecological landscapes.

    Science.gov (United States)

    Fletcher, Robert J; Acevedo, Miguel A; Reichert, Brian E; Pias, Kyle E; Kitchens, Wiley M

    2011-11-29

    Network analysis is on the rise across scientific disciplines because of its ability to reveal complex, and often emergent, patterns and dynamics. Nonetheless, a growing concern in network analysis is the use of limited data for constructing networks. This concern is strikingly relevant to ecology and conservation biology, where network analysis is used to infer connectivity across landscapes. In this context, movement among patches is the crucial parameter for interpreting connectivity but because of the difficulty of collecting reliable movement data, most network analysis proceeds with only indirect information on movement across landscapes rather than using observed movement to construct networks. Statistical models developed for social networks provide promising alternatives for landscape network construction because they can leverage limited movement information to predict linkages. Using two mark-recapture datasets on individual movement and connectivity across landscapes, we test whether commonly used network constructions for interpreting connectivity can predict actual linkages and network structure, and we contrast these approaches to social network models. We find that currently applied network constructions for assessing connectivity consistently, and substantially, overpredict actual connectivity, resulting in considerable overestimation of metapopulation lifetime. Furthermore, social network models provide accurate predictions of network structure, and can do so with remarkably limited data on movement. Social network models offer a flexible and powerful way for not only understanding the factors influencing connectivity but also for providing more reliable estimates of connectivity and metapopulation persistence in the face of limited data.

  3. Design and implementation of dynamic hybrid Honeypot network

    Science.gov (United States)

    Qiao, Peili; Hu, Shan-Shan; Zhai, Ji-Qiang

    2013-05-01

    The method of constructing a dynamic and self-adaptive virtual network is suggested to puzzle adversaries, delay and divert attacks, exhaust attacker resources and collect attacking information. The concepts of Honeypot and Honeyd, which is the frame of virtual Honeypot are introduced. The techniques of network scanning including active fingerprint recognition are analyzed. Dynamic virtual network system is designed and implemented. A virtual network similar to real network topology is built according to the collected messages from real environments in this system. By doing this, the system can perplex the attackers when Hackers attack and can further analyze and research the attacks. The tests to this system prove that this design can successfully simulate real network environment and can be used in network security analysis.

  4. Collective Intelligence in Crises

    DEFF Research Database (Denmark)

    Büscher, Monika; Liegl, Michael; Thomas, Vanessa

    2014-01-01

    New practices of social media use in emergency response seem to enable broader `situation awareness' and new forms of crisis management. The scale and speed of innovation in this field engenders disruptive innovation or a reordering of social, political, economic practices of emergency response....... By examining these dynamics with the concept of social collective intelligence, important opportunities and challenges can be examined. In this chapter we focus on socio-technical aspects of social collective intelligence in crises to discuss positive and negative frictions and avenues for innovation...

  5. Collection for Nepal

    CERN Multimedia

    Staff Association

    2015-01-01

    Following the violent earthquake in Nepal and neighbouring countries, a collection of money to help the victims was organized at CERN. A sum of 34 800 CHF was collected, and transferred to the NGO Live to Love. On July 22, the NGO sent a letter to CERN thanking for the support (see below). You can also find more information concerning this NGO and how they use their funds on our website: http://staff-association.web.cern.ch/sites/staff-association.web.cern.ch/files/Docs/Live_to_Love.pdf

  6. Collective nuclear dynamics. Proceedings

    International Nuclear Information System (INIS)

    Ivanyuk, F.A.

    1994-01-01

    The Fourth International school on nuclear physics was help on 29 Aug - 7 Sep, 1994 in Ukraine. The specialists discussed following subjects:liquid drop and the shell correction method; nuclear deformation energy and fission; nuclear structure at high spins, superdeformed states, structure of excited and exotic nuclei; nuclear fluid dynamics and large scale collective motion; order and chaos as they relate to the collective motion; quantum and interference phenomena in nuclear collisions; quasi-fission and multinucleon fragmentation effects; shell effects in non-nuclear systems; new nuclear facilities

  7. Impedance and Collective Effects

    CERN Document Server

    Metral, E; Rumolo, R; Herr, W

    2013-01-01

    This document is part of Subvolume C 'Accelerators and Colliders' of Volume 21 'Elementary Particles' of Landolt-Börnstein - Group I 'Elementary Particles, Nuclei and Atoms'. It contains the Chapter '4 Impedance and Collective Effects' with the content: 4 Impedance and Collective Effects Introduction 4.1 Space Charge 4.2 Wake Fields and Impedances 4.3 Coherent Instabilities 4.4 Landau Damping 4.5 Two-Stream Effects (Electron Cloud and Ions) 4.6 Beam-Beam Effects 4.7 Numerical Modelling

  8. Collective nuclear dynamics. Abstracts

    International Nuclear Information System (INIS)

    Abrosimov, V.I.; Kolomietz, V.M.

    1994-01-01

    The fourth International school on nuclear physics was help on 29 Aug - 7 Sep, 1994 in Ukraine. The specialists discussed following subjects: liquid drop and the shell correction method; nuclear deformation energy and fission; nuclear structure at high spins, superdeformed states, structure of excited and exotic nuclei; nuclear fluid dynamics and large scale collective motion; order and chaos as they relate to the collective motion; quantum and interference phenomena in nuclear collisions; quasi-fission and multinucleon fragmentation effects; shell effects in non-nuclear systems; new nuclear facilities

  9. Husserl on Collective Intentionality

    DEFF Research Database (Denmark)

    Szanto, Thomas

    2016-01-01

    , respectively. On this background, I will concentrate on Husserl’s alternative construal and demonstrate how it entails a robust anti-individualism regarding both the form and the subject of we-intentions. I will suggest that, contrary to appearances, Husserl does not fall prey to committing a content/vehicle...... type of fallacy, by inferring from the jointness of the contents of collective intentionality that there is one joint vehicle or, worse, some collectively conscious bearer of such. Rather, the Husserlian alternative yields a robust formal-cum-subject anti-individualism and undercuts the need...

  10. Collective nuclear dynamics. Proceedings.

    Energy Technology Data Exchange (ETDEWEB)

    Ivanyuk, F A [eds.

    1994-12-31

    The Fourth International school on nuclear physics was help on 29 Aug - 7 Sep, 1994 in Ukraine. The specialists discussed following subjects:liquid drop and the shell correction method; nuclear deformation energy and fission; nuclear structure at high spins, superdeformed states, structure of excited and exotic nuclei; nuclear fluid dynamics and large scale collective motion; order and chaos as they relate to the collective motion; quantum and interference phenomena in nuclear collisions; quasi-fission and multinucleon fragmentation effects; shell effects in non-nuclear systems; new nuclear facilities.

  11. Collective academic supervision

    DEFF Research Database (Denmark)

    Nordentoft, Helle Merete; Thomsen, Rie; Wichmann-Hansen, Gitte

    2013-01-01

    Supervision of students is a core activity in higher education. Previous research on student supervision in higher education focus on individual and relational aspects in the supervisory relationship rather than collective, pedagogical and methodical aspects of the planning of the supervision...... process. This article fills these gaps by discussing potentials and challenges in “Collective Academic Supervision”, a model for supervision at the Master of Education in Guidance at Aarhus University in Denmark. The pedagogical rationale behind the model is that students’ participation and learning...

  12. Hierarchical Network Design

    DEFF Research Database (Denmark)

    Thomadsen, Tommy

    2005-01-01

    Communication networks are immensely important today, since both companies and individuals use numerous services that rely on them. This thesis considers the design of hierarchical (communication) networks. Hierarchical networks consist of layers of networks and are well-suited for coping...... with changing and increasing demands. Two-layer networks consist of one backbone network, which interconnects cluster networks. The clusters consist of nodes and links, which connect the nodes. One node in each cluster is a hub node, and the backbone interconnects the hub nodes of each cluster and thus...... the clusters. The design of hierarchical networks involves clustering of nodes, hub selection, and network design, i.e. selection of links and routing of ows. Hierarchical networks have been in use for decades, but integrated design of these networks has only been considered for very special types of networks...

  13. Synchronization of networks

    Indian Academy of Sciences (India)

    We study the synchronization of coupled dynamical systems on networks. The dynamics is .... Such a time-varying topology can occur in social networks, computer networks, WWW ... This has the effect of reducing the spread of the transverse ...

  14. Reconfigurable network processing platforms

    NARCIS (Netherlands)

    Kachris, C.

    2007-01-01

    This dissertation presents our investigation on how to efficiently exploit reconfigurable hardware to design flexible, high performance, and power efficient network devices capable to adapt to varying processing requirements of network applications and traffic. The proposed reconfigurable network

  15. Collaborative networks: Reference modeling

    NARCIS (Netherlands)

    Camarinha-Matos, L.M.; Afsarmanesh, H.

    2008-01-01

    Collaborative Networks: Reference Modeling works to establish a theoretical foundation for Collaborative Networks. Particular emphasis is put on modeling multiple facets of collaborative networks and establishing a comprehensive modeling framework that captures and structures diverse perspectives of

  16. Introduction to computer networking

    CERN Document Server

    Robertazzi, Thomas G

    2017-01-01

    This book gives a broad look at both fundamental networking technology and new areas that support it and use it. It is a concise introduction to the most prominent, recent technological topics in computer networking. Topics include network technology such as wired and wireless networks, enabling technologies such as data centers, software defined networking, cloud and grid computing and applications such as networks on chips, space networking and network security. The accessible writing style and non-mathematical treatment makes this a useful book for the student, network and communications engineer, computer scientist and IT professional. • Features a concise, accessible treatment of computer networking, focusing on new technological topics; • Provides non-mathematical introduction to networks in their most common forms today;< • Includes new developments in switching, optical networks, WiFi, Bluetooth, LTE, 5G, and quantum cryptography.

  17. Visualization of Social Networks

    NARCIS (Netherlands)

    Boertjes, E.M.; Kotterink, B.; Jager, E.J.

    2011-01-01

    Current visualizations of social networks are mostly some form of node-link diagram. Depending on the type of social network, this can be some treevisualization with a strict hierarchical structure or a more generic network visualization.

  18. Animal transportation networks

    Science.gov (United States)

    Perna, Andrea; Latty, Tanya

    2014-01-01

    Many group-living animals construct transportation networks of trails, galleries and burrows by modifying the environment to facilitate faster, safer or more efficient movement. Animal transportation networks can have direct influences on the fitness of individuals, whereas the shape and structure of transportation networks can influence community dynamics by facilitating contacts between different individuals and species. In this review, we discuss three key areas in the study of animal transportation networks: the topological properties of networks, network morphogenesis and growth, and the behaviour of network users. We present a brief primer on elements of network theory, and then discuss the different ways in which animal groups deal with the fundamental trade-off between the competing network properties of travel efficiency, robustness and infrastructure cost. We consider how the behaviour of network users can impact network efficiency, and call for studies that integrate both network topology and user behaviour. We finish with a prospectus for future research. PMID:25165598

  19. Network development plan 1995

    International Nuclear Information System (INIS)

    Anon.

    1995-11-01

    Network plan 1995 concerns several strategic problems, among others environmental policy of power transmission lines. Possibilities of restructuring aerial cable network are described. The state of the existing systems and plans for new network systems are presented. (EG)

  20. A Collaborative Learning Network Approach to Improvement: The CUSP Learning Network.

    Science.gov (United States)

    Weaver, Sallie J; Lofthus, Jennifer; Sawyer, Melinda; Greer, Lee; Opett, Kristin; Reynolds, Catherine; Wyskiel, Rhonda; Peditto, Stephanie; Pronovost, Peter J

    2015-04-01

    Collaborative improvement networks draw on the science of collaborative organizational learning and communities of practice to facilitate peer-to-peer learning, coaching, and local adaption. Although significant improvements in patient safety and quality have been achieved through collaborative methods, insight regarding how collaborative networks are used by members is needed. Improvement Strategy: The Comprehensive Unit-based Safety Program (CUSP) Learning Network is a multi-institutional collaborative network that is designed to facilitate peer-to-peer learning and coaching specifically related to CUSP. Member organizations implement all or part of the CUSP methodology to improve organizational safety culture, patient safety, and care quality. Qualitative case studies developed by participating members examine the impact of network participation across three levels of analysis (unit, hospital, health system). In addition, results of a satisfaction survey designed to evaluate member experiences were collected to inform network development. Common themes across case studies suggest that members found value in collaborative learning and sharing strategies across organizational boundaries related to a specific improvement strategy. The CUSP Learning Network is an example of network-based collaborative learning in action. Although this learning network focuses on a particular improvement methodology-CUSP-there is clear potential for member-driven learning networks to grow around other methods or topic areas. Such collaborative learning networks may offer a way to develop an infrastructure for longer-term support of improvement efforts and to more quickly diffuse creative sustainment strategies.

  1. Violence on canadian television networks.

    Science.gov (United States)

    Paquette, Guy

    2004-02-01

    Over the past twenty years, the question of the effects of violence on television has figured prominently in public opinion and hundreds of studies have been devoted to this subject. Many researchers have determined that violence has a negative impact on behavior. The public, broadcasters and political figures all support the idea of reducing the total amount of violence on television - in particular in shows for children. A thousand programs aired between 1993 and 2001 on major non-specialty television networks in Canada were analyzed: TVA, TQS, as well as CTV and Global, private French and English networks, as well as the English CBC Radio and French Radio-Canada for the public networks. The methodology consists of a classic analysis of content where an act of violence constitutes a unit of analysis. The data collected revealed that the amount of violence has increased regularly since 1993 despite the stated willingness on the part of broadcasters to produce programs with less violence. The total number of violent acts, as well as the number of violent acts per hour, is increasing. Private networks deliver three times more violence than public networks. Researchers have also noted that a high proportion of violence occurs in programs airing before 21:00 hours, thereby exposing a large number of children to this violence. Psychological violence is taking on a more significant role in Canadian Television.

  2. Basics of Computer Networking

    CERN Document Server

    Robertazzi, Thomas

    2012-01-01

    Springer Brief Basics of Computer Networking provides a non-mathematical introduction to the world of networks. This book covers both technology for wired and wireless networks. Coverage includes transmission media, local area networks, wide area networks, and network security. Written in a very accessible style for the interested layman by the author of a widely used textbook with many years of experience explaining concepts to the beginner.

  3. Packet Tracer network simulator

    CERN Document Server

    Jesin, A

    2014-01-01

    A practical, fast-paced guide that gives you all the information you need to successfully create networks and simulate them using Packet Tracer.Packet Tracer Network Simulator is aimed at students, instructors, and network administrators who wish to use this simulator to learn how to perform networking instead of investing in expensive, specialized hardware. This book assumes that you have a good amount of Cisco networking knowledge, and it will focus more on Packet Tracer rather than networking.

  4. The Economics of Networking

    DEFF Research Database (Denmark)

    Sørensen, Olav Jull

    The literature on business networks is often oversocialized. The economic side of business is implicitly assumed. This paper analyses the economics of network behavior by loking at each of the key concepts in the Network Theory.......The literature on business networks is often oversocialized. The economic side of business is implicitly assumed. This paper analyses the economics of network behavior by loking at each of the key concepts in the Network Theory....

  5. Vulnerability and controllability of networks of networks

    International Nuclear Information System (INIS)

    Liu, Xueming; Peng, Hao; Gao, Jianxi

    2015-01-01

    Network science is a highly interdisciplinary field ranging from natural science to engineering technology and it has been applied to model complex systems and used to explain their behaviors. Most previous studies have been focus on isolated networks, but many real-world networks do in fact interact with and depend on other networks via dependency connectivities, forming “networks of networks” (NON). The interdependence between networks has been found to largely increase the vulnerability of interacting systems, when a node in one network fails, it usually causes dependent nodes in other networks to fail, which, in turn, may cause further damage on the first network and result in a cascade of failures with sometimes catastrophic consequences, e.g., electrical blackouts caused by the interdependence of power grids and communication networks. The vulnerability of a NON can be analyzed by percolation theory that can be used to predict the critical threshold where a NON collapses. We review here the analytic framework for analyzing the vulnerability of NON, which yields novel percolation laws for n-interdependent networks and also shows that percolation theory of a single network studied extensively in physics and mathematics in the last 50 years is a specific limited case of the more general case of n interacting networks. Understanding the mechanism behind the cascading failure in NON enables us finding methods to decrease the vulnerability of the natural systems and design of more robust infrastructure systems. By examining the vulnerability of NON under targeted attack and studying the real interdependent systems, we find two methods to decrease the systems vulnerability: (1) protect the high-degree nodes, and (2) increase the degree correlation between networks. Furthermore, the ultimate proof of our understanding of natural and technological systems is reflected in our ability to control them. We also review the recent studies and challenges on the

  6. Long-Term Collections

    CERN Multimedia

    Comité des collectes à long terme

    2011-01-01

    It is the time of the year when our fireman colleagues go around the laboratory for their traditional calendars sale. A part of the money of the sales will be donated in favour of the long-term collections. We hope that you will welcome them warmly.

  7. Collection for SOS animaux

    CERN Multimedia

    2005-01-01

    The Pays de Gex animal shelter is collecting funds. There will be things to buy. You will be able to make a donation and/or become a member of the association or simply get information. SOS Animaux stall (Hall, Build. 60, next to restaurant 1) On Wednesday 23 November 2005 (from 9h - 17h non-stop)

  8. Generating process model collections

    NARCIS (Netherlands)

    Yan, Z.; Dijkman, R.M.; Grefen, P.W.P.J.

    2017-01-01

    Business process management plays an important role in the management of organizations. More and more organizations describe their operations as business processes. It is common for organizations to have collections of thousands of business processes, but for reasons of confidentiality these

  9. Collection for Italy

    CERN Multimedia

    Fabiola Gianotti, Director-General, and Ghislain Roy, President of the Staff Association

    2016-01-01

    Following the earthquake of 24 August in central Italy, many of you have expressed your solidarity. The collection to support the victims raised a total of 10 000 CHF, which was transferred in its entirety to Italy’s civil protection through the Italian delegation to the CERN Council. The CERN Directorate and the CERN Staff Association sincerely thank you for your generosity.

  10. Pollen reference collection digitization

    NARCIS (Netherlands)

    Ercan, F.E.Z.; Donders, T.H.; Bijl, P.K.; Wagner, F.

    2016-01-01

    The extensive Utrecht University pollen reference collection holds thousands of pollen samples of many species and genera from all over the world and has been a basis for the widely-used North West European Pollen Flora. These samples are fixed on glass slides for microscopy use, but the aging

  11. Collective variables and dissipation

    International Nuclear Information System (INIS)

    Balian, R.

    1984-09-01

    This is an introduction to some basic concepts of non-equilibrium statistical mechanics. We emphasize in particular the relevant entropy relative to a given set of collective variables, the meaning of the projection method in the Liouville space, its use to establish the generalized transport equations for these variables, and the interpretation of dissipation in the framework of information theory

  12. Collective Action under Globalization

    DEFF Research Database (Denmark)

    Scheuer, Steen

    Collective action in the form of industrial conflict has declined dramatically since the high tide in the 1970s in Europe. This article argues that this decline is the result of significant changes in both economic and institutional factors, influencing the calculations of employees and of their ...

  13. Developing the Collection Graph

    NARCIS (Netherlands)

    Blanke, Tobias; Bryant, Michael; Speck, Reto

    2015-01-01

    Library Hi Tech, Volume 33, Issue 4, November 2015. Purpose In 2010 the European Holocaust Research Infrastructure (EHRI) was funded to support research into the Holocaust. The project follows on from significant efforts in the past to develop and record the collections of the Holocaust in several

  14. Fully electric waste collection

    CERN Multimedia

    Anaïs Schaeffer

    2015-01-01

    Since 15 June, Transvoirie, which provides waste collection services throughout French-speaking Switzerland, has been using a fully electric lorry for its collections on the CERN site – a first for the region!   Featuring a motor powered by electric batteries that charge up when the brakes are used, the new lorry that roams the CERN site is as green as can be. And it’s not only the motor that’s electric: its waste compactor and lifting mechanism are also electrically powered*, making it the first 100% electric waste collection vehicle in French-speaking Switzerland. Considering that a total of 15.5 tonnes of household waste and paper/cardboard are collected each week from the Meyrin and Prévessin sites, the benefits for the environment are clear. This improvement comes as part of CERN’s contract with Transvoirie, which stipulates that the firm must propose ways of becoming more environmentally friendly (at no extra cost to CERN). *The was...

  15. Collective excitations in nuclei

    International Nuclear Information System (INIS)

    Chomaz, Ph.

    1997-01-01

    The properties of the nucleus cannot be reduced to the properties of its constituents: it is a complex system. The fact that many properties of the nucleus are consequences of the existence of mean-field potential is a manifestation of this complexity. In particular the nucleons can thus self-organize in collective motions such as giant resonances. Therefore the study of these collective motions is a very good to understand the properties of the nucleus itself. The purpose of this article was to stress some aspects of these collective vibrations. In particular we have studied how an ensemble of fermions as the nucleus can self-organize in collective vibrations which are behaving like a gas of bosons in weak interaction. The understanding of these phenomena remains one of the important subjects of actually in the context of quantal systems in strong interaction. In particular the study of the states with one or two vibration quanta provides a direct information on the structure if nuclei close to their ground states. (author)

  16. Collective excitations in nuclei

    Energy Technology Data Exchange (ETDEWEB)

    Chomaz, Ph

    1997-12-31

    The properties of the nucleus cannot be reduced to the properties of its constituents: it is a complex system. The fact that many properties of the nucleus are consequences of the existence of mean-field potential is a manifestation of this complexity. In particular the nucleons can thus self-organize in collective motions such as giant resonances. Therefore the study of these collective motions is a very good to understand the properties of the nucleus itself. The purpose of this article was to stress some aspects of these collective vibrations. In particular we have studied how an ensemble of fermions as the nucleus can self-organize in collective vibrations which are behaving like a gas of bosons in weak interaction. The understanding of these phenomena remains one of the important subjects of actually in the context of quantal systems in strong interaction. In particular the study of the states with one or two vibration quanta provides a direct information on the structure if nuclei close to their ground states. (author) 270 refs.

  17. Innovation and collective entrepreneurship

    DEFF Research Database (Denmark)

    Spear, Roger

    2012-01-01

    different perspectives on innovation and social innovation and the dynamic interaction through collective entrepreneurship in the the social and solidarity economy; bringing out process and outcome dimensions of innovation. And it will develop an understanding of the drivers and barriers to innovation...

  18. Sample collection and documentation

    International Nuclear Information System (INIS)

    Cullings, Harry M.; Fujita, Shoichiro; Watanabe, Tadaaki; Yamashita, Tomoaki; Tanaka, Kenichi; Endo, Satoru; Shizuma, Kiyoshi; Hoshi, Masaharu; Hasai, Hiromi

    2005-01-01

    Beginning within a few weeks after the bombings and periodically during the intervening decades, investigators in Hiroshima and Nagasaki have collected samples of materials that were in the cities at the time of the bombings. Although some early efforts were not driven by specific measurement objectives, many others were. Even some of the very earliest samples collected in 1945 were based on carefully conceived research plans and detailed specifications for samples appropriate to particular retrospective measurements, i.e., of particular residual quantities remaining from exposure to the neutrons and gamma rays from the bombs. This chapter focuses mainly on the work of groups at two institutions that have actively collaborated since the 1980s in major collection efforts and have shared samples among themselves and with other investigators: the Radiation Effects Research Foundation (RERF) and its predecessor the Atomic Bomb Casualty Commission (ABCC), and Hiroshima University. In addition, a number of others are listed, who also contributed to the literature by their collection of samples. (J.P.N.)

  19. National campaign - 100 collectivities connected to the green electric power

    International Nuclear Information System (INIS)

    2004-01-01

    Since july 2004, the local collectivities, the little and medium enterprises and the craft workers can choose their electric power supplier. This offer can be a chance for the renewable energy. The association ''eco maires'' with the help of the WWF began a campaign to obtain the involvement of 100 collectivities interested by the green electric power. The project is presented. The authors presents also the new European Network on the green electric power, Eugene (European Green Electricity Network), which aims to harmonize criteria on the green electric power and to deliver certificates of quality. (A.L.B.)

  20. Synchronization coupled systems to complex networks

    CERN Document Server

    Boccaletti, Stefano; del Genio, Charo I; Amann, Andreas

    2018-01-01

    A modern introduction to synchronization phenomena, this text presents recent discoveries and the current state of research in the field, from low-dimensional systems to complex networks. The book describes some of the main mechanisms of collective behaviour in dynamical systems, including simple coupled systems, chaotic systems, and systems of infinite-dimension. After introducing the reader to the basic concepts of nonlinear dynamics, the book explores the main synchronized states of coupled systems and describes the influence of noise and the occurrence of synchronous motion in multistable and spatially-extended systems. Finally, the authors discuss the underlying principles of collective dynamics on complex networks, providing an understanding of how networked systems are able to function as a whole in order to process information, perform coordinated tasks, and respond collectively to external perturbations. The demonstrations, numerous illustrations and application examples will help advanced graduate s...