Sample records for informal communication networks

  1. Information Delivery Through Broadcasting in Satellite Communication Networks

    E-print Network

    Tassiulas, Leandros

    Information Delivery Through Broadcasting in Satellite Communication Networks Leandros Tassiulas­range multicasting capability of satellites and the asymmetry of satellite communications (high bandwidth downlink. We consider a data broadcasting model that is encountered in most asymmetric satellite communication

  2. Network information theory for wireless communications

    Microsoft Academic Search

    Liang-Liang Xie; P. R. Kumar

    2003-01-01

    Two fundamental questions arise con- cerning the emerging field of wireless networks. First, how much information can be carried over a wireless network with a multiplicity of nodes? Second, how should one operate wireless networks to realize this capacity? We establish that under a high attenua- tion regime, wireless networks obey a linear scaling law for the transport capacity, and

  3. Analysis of informal communication networks - a case study

    E-print Network

    Schoder, Detlef

    The structure and dynamics of informal communication networks are of central importance for the functionality of enterprise workflows and for performance and innovation of knowledge-centric organizations. While most ...

  4. Information Theory and Communication Networks: An Unconsummated Union

    Microsoft Academic Search

    Anthony Ephremides; Bruce E. Hajek

    1998-01-01

    Information theory has not yet had a direct impact on networking, although there are similarities in concepts and methodologies that have consistently attracted the attention of researchers from both fields. In this paper, we review several topics that are related to communication networks and that have an information-theoretic flavor, including multiaccess protocols, timing channels, effective bandwidth of bursty data sources,

  5. Information and Communication Complexity of Networked Control Serdar Yuksel1

    E-print Network

    Yüksel, Serdar

    , 2013 Abstract Information and communication complexity of a networked control system identifies team problem with L control stations (these will be referred to as decision makers and denoted by DMs and Engineering Research Council of Canada (NSERC). Email: yuksel@mast.queensu.ca. 1 #12;Plant Station 4 Station 3

  6. Information-theoretic data-hiding for public network security, services control and secure communications

    Microsoft Academic Search

    Sviatoslav Voloshynovskiyl; F. Deguillaume; O. Koval; T. Pun

    2003-01-01

    In this paper we introduce and develop a framework for the data-hiding technologies that aim at resolving emerging problems of modern public networks. First, we emphasize the main open issues in public network security, quality of services control and secure communications. Secondly, we formulate digital data hiding as communications with side information and advocate an appropriate information-theoretic framework for the

  7. New results in network information theory: scaling laws for wireless communication and optimal strategies for information transport

    Microsoft Academic Search

    Liang-Liang Xie; P. R. Kumar

    2002-01-01

    We present a network information theory for wireless communications. This theory addresses the following issues: (i) How the amount of information that can be carried over a wireless network scales as the number n of nodes in the network increases. (ii) Obtains bounds on the pre-constant in the scaling law, thus obtaining bounds on network capability as a function of

  8. ContactMap: Integrating Communication and Information Through Visualizing Personal Social Networks

    Microsoft Academic Search

    Bonnie A. Nardi; Steve Whittaker; Ellen Isaacs; Mike Creech; Jeff Johnson; John Hainsworth

    What could provide an organizing principle for advanced user interfaces that afford information and communication services in a single integrated system? Based on our research on communication patterns in the workplace, our answer is models of personal social networks. Our research showed that people invest considerable effort in maintaining links with networks of colleagues, acquaintances and friends, and that these

  9. Information -Communication Communication des entreprises

    E-print Network

    Sart, Remi

    Information - Communication 2 PARCOURS Communication des entreprises Communication et solidarité;2 Information - Communication UFR Langues Appliquées, Commerce et Communication PRÉSENTATION Objectifs La Licence Information et communication est destinée aux étudiants qui souhaitent suivre un parcours

  10. Electronic Communication Networks.

    ERIC Educational Resources Information Center

    Raimondi, Sharon L.

    1984-01-01

    Discusses educational uses, types, operation, advantages, popular features, and subscription rates of electronic communication networks. Factors to consider when choosing a network are described, and a table listing networks designed for educators includes information on the network producer, target audience, features, subscription rates, and…

  11. 2416 IEEE TRANSACTIONS ON INFORMATION THEORY, VOL. 44, NO. 6, OCTOBER 1998 Information Theory and Communication Networks

    E-print Network

    Hajek, Bruce

    2416 IEEE TRANSACTIONS ON INFORMATION THEORY, VOL. 44, NO. 6, OCTOBER 1998 Information Theory (Invited Paper) Abstract--Information theory has not yet had a direct impact on networking, although INFORMATION theory is the conscience of the theory of communication; it has defined the "playing field" within

  12. Health care communication networks: disseminating employee information for hospital security.

    PubMed

    Sumner, Jennifer; Liberman, Aaron; Rotarius, Timothy; Wan, Thomas T H; Eaglin, Ronald

    2009-01-01

    Health care in the United States is a system that, organizationally speaking, is fragmented. Each hospital facility is independently operated and is responsible for the hiring of its own employees. Corrupt individuals can take advantage of this fragmentation and move from hospital to hospital, gaining employment while hiding previous employment history. However, the need to exchange pertinent information regarding employees will become necessary as hospitals seek to fill positions throughout their organizations. One way to promote this information exchange is to develop trusted information sharing networks among hospital units. This study examined the problems surrounding organizational information sharing and the cultural factors necessary to enhance the exchange of employee information. Surveys were disseminated to 2,603 hospital chief executive officers and chief information officers throughout the nation. A sample of 154 respondents provided data into their current hiring practices and on their willingness to engage in the sharing of employee information. Findings indicated that, although fear of defamation and privacy violations do hinder the exchange of information between hospitals during the hiring process, by increasing external trust, linking the sharing process with the organizational goals of the hospital, and developing a "sharing culture" among hospitals, the exchange of employee information could be enhanced. PMID:19910705

  13. Information & Communications

    E-print Network

    Popeea, Corneliu - Chair for Foundations of Software Reliability and Theoretical Computer Science

    Model & % " " ( & # % & ) # # * % ' ) # # * & Metabolism Drug Screening #12;© Siemens AG, CT IC 4, 2003 IC 4, 2003 Information & Communications Neural Computation EmotionLong Term Memory Working Memory Attentional Filtering Object/Spatial Memory Rule Memory Attention Object-Based Attention, Spatial Attention

  14. Biomass Program Outreach and Communication The Bioenergy Feedstock Information Network (BFIN)

    E-print Network

    + Biomass Program Outreach and Communication The Bioenergy Feedstock Information Network (BFIN) About ten years ago ORNL launched BFIN providing a gateway to a wealth of biomass feedstock information by ORNL. Regional partnership workshops The Regional Biomass Energy Feedstock Partnership is comprised

  15. INFORMATION & COMMUNICATION

    E-print Network

    Jackson, Daniel

    ) TRANSFORMING GLOBAL INFORMATION AND COMMUNICATION MARKETS The Political Economy of Innovation Peter F. Cowhey) Information Revolution and Global Politics series 2012 Surveillance Studies Book Prize, Surveillance Studies Howard Rheingold A media guru shows us how to use social media intelligently, humanely, and, above all

  16. R-ALOHA protocol for SS inter-vehicle communication network using head spacing information

    Microsoft Academic Search

    Young-An Kim; Masao Nakagawa

    1996-01-01

    The purpose of the studies is to improve the safety of road traffic systems and the smooth control of the traffic flow by providing information to vehicles. This paper assumes that the vehicles incidentally close to each other, form and manage a locally autonomous decentralized dynamic network. An R-ALOHA (reservation-ALOHA) protocol for the spread spectrum (SS) inter-vehicle communication network using

  17. Information and Communication Technology

    NSDL National Science Digital Library

    Communication is a central aspect of all our lives. Today, our modes of communication are highly dependent on technologies such as the internet, wireless networks, phones, and computers. This issue of Topic in Depth explores the ways these forms of communication are part of our lives and highlights some new directions in communication technology.WordIQ Dictionary and Encyclopedia (1) offers this definition: "Communication is the process of exchanging information usually via a common system of symbols." The website explains some of the key process involved in communication and describes different forms of communication, such as animal communication, interpersonal communication, and computer-mediated communication. Also taking a broad view on communication, this world history website (2) provides some background on the mathematical theories that are used in designing telecommunications systems. The articles highlighted on this website from the Center for the Study of Technology and Society (4) attest to the far reaching influence of communication technology. As research on the MediaLab Europe website suggests (5), we have moved into not just developing technology that mediates interpersonal communication (such as phones) but also creating "intimate and personal connections with and through new technologies." This NSF website (6) also highlights some recent discoveries in Computer Information Science and Engineering. Finally, this article from First Monday (7) discusses the far-reaching effects these new developments in technology and globalization are having on language and learning.

  18. Informing the network: Improving communication with interface communities during wildland fire

    USGS Publications Warehouse

    Taylor, J.G.; Gillette, S.C.; Hodgson, R.W.; Downing, J.L.; Burns, M.R.; Chavez, D.J.; Hogan, J.T.

    2007-01-01

    An interagency research team studied fire communications that took place during different stages of two wildfires in southern California: one small fire of short duration and one large fire of long duration. This "quick- response" research showed that pre-fire communication planning was particularly effective for smaller fire events and parts of that planning proved invaluable for the large fire event as well. Information seeking by the affected public relied on locally convenient sources during the small fire. During the large fire, widespread evacuations disrupted many of the local informal communication networks. Residents' needs were for "real-time, " place-specific information: precise location, severity, size, and direction of spread of the fires. Fire management agencies must contribute real-time, place-specific fire information when it is most needed by the affected public, as they try to make sense out of the chaos of a wildland fire. Disseminating fire information as broadly as possible through multiple pathways will maximize the probability of the public finding the information they need. ?? Society for Human Ecology.

  19. Sensor Networks Communication strategies

    E-print Network

    Chisci, Luigi

    Outline Sensor Networks Communication strategies Follow on Distributed estimation in sensor@dsi.unifi.it February 1, 2007 A. Benavoli Fully Decentralized Networks #12;Outline Sensor Networks Communication strategies Follow on Outline 1 Sensor Networks An introduction to Sensor Networks Network architectures

  20. Extracting information from informal communication

    E-print Network

    Rennie, Jason D. M. (Jason Daniel Malyutin), 1976-

    2007-01-01

    This thesis focuses on the problem of extracting information from informal communication. Textual informal communication, such as e-mail, bulletin boards and blogs, has become a vast information resource. However, such ...

  1. Information and Communication Technologies

    E-print Network

    Liley, David

    Information and Communication Technologies Undergraduate and TAFE Courses swinburne.edu.au Can innovation and excellence in the training sector across Australia. Information and Communication Technologies, but multiple career doors. Dynamic and constantly evolving, information and communication technologies provide

  2. International Journal of Communication Networks and Information Security (IJCNIS) Vol. 1, No. 2, August 2009 A Secured Service Level Negotiation

    E-print Network

    Paris-Sud XI, Université de

    9 International Journal of Communication Networks and Information Security (IJCNIS) Vol. 1, No. 2S and security guarantees which may depend on the used access network. In that environment, the challenge, August 2009 A Secured Service Level Negotiation In Ubiquitous Environments Mohamed Aymen Chalouf1

  3. A universal quantum information processor for scalable quantum communication and networks.

    PubMed

    Yang, Xihua; Xue, Bolin; Zhang, Junxiang; Zhu, Shiyao

    2014-01-01

    Entanglement provides an essential resource for quantum computation, quantum communication, and quantum networks. How to conveniently and efficiently realize the generation, distribution, storage, retrieval, and control of multipartite entanglement is the basic requirement for realistic quantum information processing. Here, we present a theoretical proposal to efficiently and conveniently achieve a universal quantum information processor (QIP) via atomic coherence in an atomic ensemble. The atomic coherence, produced through electromagnetically induced transparency (EIT) in the ?-type configuration, acts as the QIP and has full functions of quantum beam splitter, quantum frequency converter, quantum entangler, and quantum repeater. By employing EIT-based nondegenerate four-wave mixing processes, the generation, exchange, distribution, and manipulation of light-light, atom-light, and atom-atom multipartite entanglement can be efficiently and flexibly achieved in a deterministic way with only coherent light fields. This method greatly facilitates the operations in quantum information processing, and holds promising applications in realistic scalable quantum communication and quantum networks. PMID:25316514

  4. Information and Communications Technologies Tutorials

    NSDL National Science Digital Library

    The Information and Communications Technologies Center (ICT) presents this collection of links to a number of online tutorials. The tutorials fall under the categories of electronics, fiber optics, general computing and programming, general telecommunications, java, math, matlab, networking and physics.

  5. General practice and the Internet revolution. Use of an Internet social network to communicate information on prevention in France.

    PubMed

    Veuillotte, Isabelle; Morel, Gilles; Pitois, Stephane; Haler, Renaud; Mercier, Patricia; Aubry, Catherine; Cannet, Didier

    2015-03-01

    The popularity of social networks and the huge number of exchanges have made them immensely important for the communication of information. This French study explored prevention in hereditary breast cancer using a social Internet network to communicate information. The principal objective was to inform French women aged from 20 to 50 years, using the social network Facebook, about the warning signs of breast cancer in cases of a predisposition to the disease due to a genetic mutation. The secondary objectives were to inform people about screening. An information page entitled "hereditary breast cancer: and if I was concerned?" was distributed in 3 different ways: from friend to friend, via groups of persons, and by targeted advertising. Four articles and 11 messages were distributed over 27 days. The total number of visits for this period amounted to 1019. A total of 81 percent of the Internauts were women and 55 percent of the visitors were aged between 25 and 44 years. Other information campaigns concerning public health issues could be conducted using this tool. A legal framework is necessary to preserve the quality of the medical information provided. This new means of communication, used for prevention purposes, will add to other frequently used methods of communication. PMID:25784641

  6. Optimization of Communication Networks

    Microsoft Academic Search

    Jörg Eberspächer; Moritz Kiese; Roland Wessäly

    \\u000a Global communication networks (e.g. telephone networks, cellular radio networks, or the Internet) have become the nervous\\u000a system of today’s economy and society. Due to ongoing technological progress in electronics, computer and communication technologies,\\u000a not only the number of users in the networks keeps growing, but new applications like radio and TV in the Internet, e-business,\\u000a and interactive games are upcoming.

  7. Overview of the Space Station communications networks

    NASA Technical Reports Server (NTRS)

    Smith, Joseph F.; Willett, Daniel; Paul, Sunil

    1990-01-01

    Within the Space Station Freedom program, the communications and data-processing capabilities that will be used to handle the operational and scientific information needs will be provided by a Space Station information and communications system. This system will be composed of a variety of elements, networks, and subnetworks. The networks and how they are interconnected are described. The discussion covers communications system elements and services, elements of the onboard systems, wide-area transport network elements, and command and control elements.

  8. Aboriginal Information & Communication Technologies

    E-print Network

    Martin, Jeff

    Networking (30 Hours) · Networking Protocols (30 Hours) · Advanced Networking (30 Hours) · Windows Design (24 Hours) · Introduction to Business Analysis (30 Hours) · Information Assurance and Security application form admission requirements 2. Successfully pass the entrance exam 3. Successfully pass

  9. Clinical social networking--a new revolution in provider communication and delivery of clinical information across providers of care?

    PubMed

    Kolowitz, Brian J; Lauro, Gonzalo Romero; Venturella, James; Georgiev, Veliyan; Barone, Michael; Deible, Christopher; Shrestha, Rasu

    2014-04-01

    The adoption of social media technologies appears to enhance clinical outcomes through improved communications as reported by Bacigalupe (Fam Syst Heal 29(1):1-14, 2011). The ability of providers to more effectively, directly, and rapidly communicate among themselves as well as with patients should strengthen collaboration and treatment as reported by Bacigalupe (Fam Syst Heal 29(1):1-14, 2011). This paper is a case study in one organization's development of an internally designed and developed social technology solution termed "Unite." The Unite system combines social technologies' features including push notifications, messaging, community groups, and user lists with clinical workflow and applications to construct dynamic provider networks, simplify communications, and facilitate clinical workflow optimization. Modeling Unite as a social technology may ease adoption barriers. Developing a social network that is integrated with healthcare information systems in the clinical space opens the doors to capturing and studying the way in which providers communicate. The Unite system appears to have the potential to breaking down existing communication paradigms. With Unite, a rich set of usage data tied to clinical events may unravel alternative networks that can be leveraged to advance patient care. PMID:24149968

  10. Information and Communication

    E-print Network

    Liley, David

    Information and Communication Technologies }2014 swinburne.edu.au Degrees and diplomas #12;`I wasn.' Michelle Bachelor of Business Information Systems/ Bachelor of Business #12;}}Find creative solutions to high-tech problems Dynamic and constantly evolving, the field of information and communication

  11. Information and Communication

    E-print Network

    Liley, David

    the Bachelor of Information Technology entry on page10. Showcase your cyber-security skills Each year SwinburneInformation and Communication Technologies }2015 swinburne.edu.au Degrees and diplomas #12-tech problems Dynamic and constantly evolving, the field of information and communication technologies (ICT

  12. Communication Networks and Modernization

    Microsoft Academic Search

    1993-01-01

    The last three decades have witnessed an acceleration in the use, demand, and need of telecommunications, data communication, and mass communication transmitted and, increasingly, integrated into networks. This acceleration can be explained by a synthesis of the modernization theories of Giddens (the concept of time-space distantiation) and Beniger (the problems of control in a complex society). A central theme is

  13. The Informal Communication Network Built by Domingo Del Monte from Havana Between 1824 and 1845

    Microsoft Academic Search

    2009-01-01

    : This research aims to study the informal channels of communication built by Domingo del Monte, and the circle of authors who surrounded him. During the transition from the Ancien Régime to liberalism, del Monte and his followers were keen in using Havana to launch their identity project, so it would spread throughout the island of Cuba and into the

  14. Connection-information-based connection rerouting for connection-oriented mobile communication networks

    NASA Astrophysics Data System (ADS)

    Song, Minho; Choi, Yanghee; Kim, Chongsang

    1998-06-01

    To date, various connection rerouting methods for connection-oriented mobile networks have been proposed. The previous methods, however, are limited to specific topologies or environments. In this paper, we propose the connection-information-based rerouting widely applicable to various connection-oriented mobile networks. This method requires neither a specific topology nor a complex connection, enables fast rerouting, provides appropriate route optimality, and can be extended easily.

  15. Chapter 7. Network Information Theory Network Information Theory

    E-print Network

    Chapter 7. Network Information Theory 7-1 Network Information Theory Faculty Professor Lizhong in our groups is to extend the conventional information theory to develop theoretical tools that can information theory, while had great successes in understanding static point-to- point communication problems

  16. Simulator of Space Communication Networks

    NASA Technical Reports Server (NTRS)

    Clare, Loren; Jennings, Esther; Gao, Jay; Segui, John; Kwong, Winston

    2005-01-01

    Multimission Advanced Communications Hybrid Environment for Test and Evaluation (MACHETE) is a suite of software tools that simulates the behaviors of communication networks to be used in space exploration, and predict the performance of established and emerging space communication protocols and services. MACHETE consists of four general software systems: (1) a system for kinematic modeling of planetary and spacecraft motions; (2) a system for characterizing the engineering impact on the bandwidth and reliability of deep-space and in-situ communication links; (3) a system for generating traffic loads and modeling of protocol behaviors and state machines; and (4) a system of user-interface for performance metric visualizations. The kinematic-modeling system makes it possible to characterize space link connectivity effects, including occultations and signal losses arising from dynamic slant-range changes and antenna radiation patterns. The link-engineering system also accounts for antenna radiation patterns and other phenomena, including modulations, data rates, coding, noise, and multipath fading. The protocol system utilizes information from the kinematic-modeling and link-engineering systems to simulate operational scenarios of space missions and evaluate overall network performance. In addition, a Communications Effect Server (CES) interface for MACHETE has been developed to facilitate hybrid simulation of space communication networks with actual flight/ground software/hardware embedded in the overall system.

  17. Social network analysis and dual rover communications

    NASA Astrophysics Data System (ADS)

    Litaker, Harry L.; Howard, Robert L.

    2013-10-01

    Social network analysis (SNA) refers to the collection of techniques, tools, and methods used in sociometry aiming at the analysis of social networks to investigate decision making, group communication, and the distribution of information. Human factors engineers at the National Aeronautics and Space Administration (NASA) conducted a social network analysis on communication data collected during a 14-day field study operating a dual rover exploration mission to better understand the relationships between certain network groups such as ground control, flight teams, and planetary science. The analysis identified two communication network structures for the continuous communication and Twice-a-Day Communication scenarios as a split network and negotiated network respectfully. The major nodes or groups for the networks' architecture, transmittal status, and information were identified using graphical network mapping, quantitative analysis of subjective impressions, and quantified statistical analysis using Sociometric Statue and Centrality. Post-questionnaire analysis along with interviews revealed advantages and disadvantages of each network structure with team members identifying the need for a more stable continuous communication network, improved robustness of voice loops, and better systems training/capabilities for scientific imagery data and operational data during Twice-a-Day Communications.

  18. Hyperswitch Communication Network Computer

    NASA Technical Reports Server (NTRS)

    Peterson, John C.; Chow, Edward T.; Priel, Moshe; Upchurch, Edwin T.

    1993-01-01

    Hyperswitch Communications Network (HCN) computer is prototype multiple-processor computer being developed. Incorporates improved version of hyperswitch communication network described in "Hyperswitch Network For Hypercube Computer" (NPO-16905). Designed to support high-level software and expansion of itself. HCN computer is message-passing, multiple-instruction/multiple-data computer offering significant advantages over older single-processor and bus-based multiple-processor computers, with respect to price/performance ratio, reliability, availability, and manufacturing. Design of HCN operating-system software provides flexible computing environment accommodating both parallel and distributed processing. Also achieves balance among following competing factors; performance in processing and communications, ease of use, and tolerance of (and recovery from) faults.

  19. Maine's Support Network for Rural Special Educators. Success through Communication. Information Bulletin #31.

    ERIC Educational Resources Information Center

    National Association of State Directors of Special Education, Washington, DC.

    This two-page flyer briefly describes Maine's Support Network for Rural Special Educators, which provides content-related information and support to special education teachers and related service personnel. Initiated in 1986 to combat the high turnover rate of special education staff in Maine's rural schools, the program stresses the role of…

  20. Covert Communication Networks

    E-print Network

    Nix, Timothy Glen

    2013-08-02

    to the Browser . . . . . . . . . . . . . . . . . . . . 140 9.6.2 Connecting to the Proxy . . . . . . . . . . . . . . . . . . . . . 140 9.6.3 The Intermediate Nodes . . . . . . . . . . . . . . . . . . . . . 141 9.6.4 Results... of network are signi cantly more stringent than for traditional privacy and anonymity networks such as Tor [17]. Traditional means of Internet communications, such as email and instant messaging, would not be pro- tected. Though encrypted tra c would...

  1. Application examples of the network fixed point theory for space-air-ground integrated communication network

    Microsoft Academic Search

    Liu Hui; Zhang Jun; L. L. Cheng

    2010-01-01

    The space-air-ground integrated network is based on the modern communication networks and integrated the latest communication and computer technologies, such that connects all various networks together to form a very huge and complicated network topology that has the best sharing of the global information and resources. This paper is treating the communication network as a space which is formed by

  2. Multiaccess and fading in communication networks

    E-print Network

    Yeh, Edmund Meng, 1971-

    2001-01-01

    Two fundamental issues in the design of wireless communication networks are the interference among multiple users and the time-varying nature of the fading wireless channel. We apply fundamental techniques in information ...

  3. Quantum network communication -- the butterfly and beyond

    E-print Network

    Debbie Leung; Jonathan Oppenheim; Andreas Winter

    2009-12-03

    We study the k-pair communication problem for quantum information in networks of quantum channels. We consider the asymptotic rates of high fidelity quantum communication between specific sender-receiver pairs. Four scenarios of classical communication assistance (none, forward, backward, and two-way) are considered. (i) We obtain outer and inner bounds of the achievable rate regions in the most general directed networks. (ii) For two particular networks (including the butterfly network) routing is proved optimal, and the free assisting classical communication can at best be used to modify the directions of quantum channels in the network. Consequently, the achievable rate regions are given by counting edge avoiding paths, and precise achievable rate regions in all four assisting scenarios can be obtained. (iii) Optimality of routing can also be proved in classes of networks. The first class consists of directed unassisted networks in which (1) the receivers are information sinks, (2) the maximum distance from senders to receivers is small, and (3) a certain type of 4-cycles are absent, but without further constraints (such as on the number of communicating and intermediate parties). The second class consists of arbitrary backward-assisted networks with 2 sender-receiver pairs. (iv) Beyond the k-pair communication problem, observations are made on quantum multicasting and a static version of network communication related to the entanglement of assistance.

  4. The physics of communicability in complex networks

    NASA Astrophysics Data System (ADS)

    Estrada, Ernesto; Hatano, Naomichi; Benzi, Michele

    2012-05-01

    A fundamental problem in the study of complex networks is to provide quantitative measures of correlation and information flow between different parts of a system. To this end, several notions of communicability have been introduced and applied to a wide variety of real-world networks in recent years. Several such communicability functions are reviewed in this paper. It is emphasized that communication and correlation in networks can take place through many more routes than the shortest paths, a fact that may not have been sufficiently appreciated in previously proposed correlation measures. In contrast to these, the communicability measures reviewed in this paper are defined by taking into account all possible routes between two nodes, assigning smaller weights to longer ones. This point of view naturally leads to the definition of communicability in terms of matrix functions, such as the exponential, resolvent, and hyperbolic functions, in which the matrix argument is either the adjacency matrix or the graph Laplacian associated with the network. Considerable insight on communicability can be gained by modeling a network as a system of oscillators and deriving physical interpretations, both classical and quantum-mechanical, of various communicability functions. Applications of communicability measures to the analysis of complex systems are illustrated on a variety of biological, physical and social networks. The last part of the paper is devoted to a review of the notion of locality in complex networks and to computational aspects that by exploiting sparsity can greatly reduce the computational efforts for the calculation of communicability functions for large networks.

  5. Effective and efficient communication of information

    Microsoft Academic Search

    Jan Willem Marck; Leon Kester; Jeroen Bergmans; Miranda van Iersel; Eelke van Foeken

    2008-01-01

    Research fields such as Network Enabled Capabilities, ubiquitous computing and distributed sensor networks, etc. deal with a lot of information and a lot of different processes to fuse data to a desired level of situation awareness. Already quite some research is done in applying information theoretic concepts to sensor management. Effective communication between functional components in the fusion hierarchy can

  6. Network Science for Communication Networks Yuval Shavitt

    E-print Network

    Schuster, Assaf

    Network Science for Communication Networks Yuval Shavitt School of Electrical Engineering shavitt@eng.tau.ac.il http://www.netDIMES.org http://www.eng.tau.ac.il/~shavitt DIMES #12;Network Science · Networks appear #12;Network Science · We all look at networks · We can share tools and ideas · Some problems

  7. Florida Information Resource Network.

    ERIC Educational Resources Information Center

    Watson, Francis C.

    1986-01-01

    The Florida Information Resource Network (FIRN) is an effort by the Florida education community and the Florida Legislature to provide an electronic link among all agencies, institutions, and schools in the public education system. The communications link, perhaps one of the most advanced in the nation, has three purposes: (1) to provide equal…

  8. NASA technology transfer network communications and information system: TUNS user survey

    NASA Technical Reports Server (NTRS)

    1992-01-01

    Applied Expertise surveyed the users of the deployed Technology Utilization Network System (TUNS) and surveyed prospective new users in order to gather background information for developing the Concept Document of the system that will upgrade and replace TUNS. Survey participants broadly agree that automated mechanisms for acquiring, managing, and disseminating new technology and spinoff benefits information can and should play an important role in meeting NASA technology utilization goals. However, TUNS does not meet this need for most users. The survey describes a number of systematic improvements that will make it easier to use the technology transfer mechanism, and thus expedite the collection and dissemination of technology information. The survey identified 26 suggestions for enhancing the technology transfer system and related processes.

  9. Using Geospatial Information in Sensor Networks

    Microsoft Academic Search

    John Heidemann; Nirupama Bulusu

    2001-01-01

    This paper describes several ways sensor networks can ben- efit from geospatial information and identifies two research directions. First, better models of localization error, logi- cal location, and communications costs are required to un- derstand the interactions between spatial information and control and communications algorithms in sensor networks. Second, wider use of spatial information in densely de- ployed sensor networks

  10. Information and Communication

    E-print Network

    Henkel, Werner

    our everyday life, our society, and the environment. Exam- ples comprise the World - System capacity management and optimization - Information transmission - Network protocols - Information security All these research areas are strongly inter-related and the strength of a research cluster in "com

  11. Exploring Temporal Communication Through Social Networks

    Microsoft Academic Search

    Liaquat Hossain; Kon Shing Kenneth Chung; Shahriar Tanvir Hasan Murshed

    2007-01-01

    The dissemination of information in social networks and the relative effect of ICT (Information and Communications Technology) use has long been an interesting area of study in the field of sociology, human computer interaction and computer supported cooperative work. To date, a lot of research has been conducted regarding an actor's mobile phone usage behavior while disseminating information within a

  12. Video Communication Networks Dan Schonfeld

    E-print Network

    Schonfeld, Dan

    a decentralized communication system that could survive the impact of a nuclear attack. This proposal employed. The ARPANET was initially an experimental communication network that consisted of four nodes: UCLA, UCSB, SRI

  13. DatComNet: Designing an Intelligent Visual Tool for Teaching Data Communication and Network Information Systems

    Microsoft Academic Search

    Abdel Badeea Salem; Ibrahiem M. M. El Emary; Hussain F. Sindi

    2006-01-01

    DatComNet is a tutorial tool designed to assist students in understanding the concepts of designing, implementing and managing the data communication networks. It is particularly useful for computer science and computer engineering students in computer communication network courses. The DatComNet interface is written in C++ and clips. The use of Java as the language of implementation provides platform independent access

  14. Sensor array networks and long distance communications

    Microsoft Academic Search

    Peter P. Budulas; Cynthia S. Pierce; Philip J. Emmerman

    2001-01-01

    This paper will discuss the on-going research at Army Research Laboratory (ARL) supporting long distance communication for networked sensor arrays. As the Army continues to move forward in the development of remote, distributed, unattended, intelligence sensors, the need for the resultant information to reach the command and control center increases. In the case of sensor array networks the command and

  15. Hyperswitch communication network

    NASA Technical Reports Server (NTRS)

    Peterson, J.; Pniel, M.; Upchurch, E.

    1991-01-01

    The Hyperswitch Communication Network (HCN) is a large scale parallel computer prototype being developed at JPL. Commercial versions of the HCN computer are planned. The HCN computer being designed is a message passing multiple instruction multiple data (MIMD) computer, and offers many advantages in price-performance ratio, reliability and availability, and manufacturing over traditional uniprocessors and bus based multiprocessors. The design of the HCN operating system is a uniquely flexible environment that combines both parallel processing and distributed processing. This programming paradigm can achieve a balance among the following competing factors: performance in processing and communications, user friendliness, and fault tolerance. The prototype is being designed to accommodate a maximum of 64 state of the art microprocessors. The HCN is classified as a distributed supercomputer. The HCN system is described, and the performance/cost analysis and other competing factors within the system design are reviewed.

  16. Information and communication technology

    NASA Technical Reports Server (NTRS)

    Edelson, Burton I.; Pelton, Joseph N.; Bostian, Charles W.; Brandon, William T.; Chan, Vincent W. S.; Hager, E. Paul; Helm, Neil R.; Jennings, Raymond D.; Kwan, Robert K.; Mahle, Christoph E.

    1994-01-01

    NASA and the National Science Foundation (NSF) commissioned a panel of U.S. experts to study the international status of satellite communications systems and technology. The study covers emerging systems concepts, applications, services, and the attendant technologies. The panel members traveled to Europe, Japan, and Russia to gather information firsthand. They visited 17 sites in Europe, 20 in Japan, and 4 in Russia. These included major manufacturers, government organizations, service providers, and associated research and development facilities. The panel's report was reviewed by the sites visited, by the panel, and by representatives of U.S. industry. The report details the information collected and compares it to U.S. activities.

  17. Efficient Collective Communication in Optical Networks

    Microsoft Academic Search

    Jean-claude Bermond; Luisa Gargano; Stephane Perennes; Adele A. Rescigno; Ugo Vaccaro

    1996-01-01

    This paper studies the problems of One--to--All and All--to--All Communication in opticalnetworks. In such networks the vast bandwidth available is utilized through wavelength division multiplexing: a single physical optical link can carry several logical signals, provided thatthey are transmitted on different wavelengths. In this paper we consider both single--hop andmultihop optical networks. In single--hop networks the information, once transmitted as

  18. Chaining for Securing Data Provenance in Distributed Information Networks

    E-print Network

    California at Davis, University of

    for information trustworthiness assessment, copyright clearance, data reconciliation, and data replication. While Information networks are networks that use the networking technologies such as the Internet and wireless communication for distributing and sharing information among different in- formation processing entities

  19. College of Communication and Information COM Communication

    E-print Network

    MacAdam, Keith

    .Designedtoenhanceeffective communication and informed use of the mass media. COM 181 BASIC PUBLIC SPEAKING. (3) A course designed to give, Basic Public Speaking. It will count toward partial completion of the oral communication skills the student platform experience in the fundamentals of effective speaking. COM 199 PRESENTATIONAL

  20. Effective and Efficient Communication of Information

    Microsoft Academic Search

    Jan Willem Marck; Leon Kester; Miranda van Iersel; Jeroen Bergmans; Eelke van Foeken

    Research fields such as Network Enabled Capabilities, ubiquitous computing and distributed sensor networks, etc. deal with\\u000a a lot of information and a lot of different processes to fuse data to a desired level of situation awareness. Already quite\\u000a some research is done in applying information theoretic concepts to sensor management. Effective communication between functional\\u000a components in the fusion hierarchy can

  1. Information Computer Communications Policy, 2: The Usage of International Data Networks in Europe.

    ERIC Educational Resources Information Center

    Organisation for Economic Cooperation and Development, Paris (France).

    This study of the development of international data networks, a phenomena of the 1970's, and policy issues arising from their use is an in depth investigation of 24 private and six public European networks commissioned from Logica Limited and sponsored by the governments of France, Germany, the Netherlands, Norway, Spain, and Sweden. The report…

  2. Communication Dynamics of Blog Networks

    NASA Astrophysics Data System (ADS)

    Goldberg, Mark; Kelley, Stephen; Magdon-Ismail, Malik; Mertsalov, Konstantin; Wallace, William (Al)

    We study the communication dynamics of Blog networks, focusing on the Russian section of LiveJournal as a case study. Communication (blogger-to-blogger links) in such online communication networks is very dynamic: over 60% of the links in the network are new from one week to the next, though the set of bloggers remains approximately constant. Two fundamental questions are: (i) what models adequately describe such dynamic communication behavior; and (ii) how does one detect the phase transitions, i.e. the changes that go beyond the standard high-level dynamics? We approach these questions through the notion of stable statistics. We give strong experimental evidence to the fact that, despite the extreme amount of communication dynamics, several aggregate statistics are remarkably stable. We use stable statistics to test our models of communication dynamics postulating that any good model should produce values for these statistics which are both stable and close to the observed ones. Stable statistics can also be used to identify phase transitions, since any change in a normally stable statistic indicates a substantial change in the nature of the communication dynamics. We describe models of the communication dynamics in large social networks based on the principle of locality of communication: a node's communication energy is spent mostly within its own "social area," the locality of the node.

  3. CMPSCI 791N: Algorithms for Communication Networks Seminar information: Fall 1999

    E-print Network

    Adler, Micah

    in this area, and also explore networking issues where algorithmic techniques may lead to interesting research problems. Students will be expected to present papers during the lectures from a list provided with the design and analysis of algorithms at an advanced undergrad­ uate level. Textbook: We shall be covering

  4. User identification in encrypted network communications

    Microsoft Academic Search

    Robert Koch; Gabi Dreo Rodosek

    2010-01-01

    Encrypting network traffic is a normal procedure to protect information for exchange. This prevents tapping and manipulation but it also hampers intrusion as well as data leakage and misuse detection. Obtaining knowledge about users of encrypted communications is, however, beneficial in terms of monitoring access, security and accounting reasons. Thus, the objective is to provide evidence of the source of

  5. Wearable DC Powerline Communication Network using Conductive Fabrics

    Microsoft Academic Search

    Eric Wade; H. Harry Asada

    2004-01-01

    A wearable DC power line communication network is proposed for health sensing and rehabilitation. This system provides a network through which multiple sensors and actuators can send and receive both information and power. With such a network, sensors placed at many remote locations on the human body can send and receive information to a centralized power\\/data coordinator. This system consists

  6. Efficient Solutions to Multicast Routing in Communication Networks

    Microsoft Academic Search

    Kia Makki; Niki Pissinou; Ophir Frieder

    1996-01-01

    An important problem in both wireless and wired communication networks is to be able to efficiently multicst information to a group of network sites. Multicasting reduces the transmission overhead of both wireless and wired networks and the time it takes for all the nodes in the subset to receive the information. Since transmission bandwidth is a scarce commodity especially in

  7. Integrated text-communication services digital networks

    NASA Astrophysics Data System (ADS)

    Montemurro, R.; Villani, F.

    1980-12-01

    Circuit and packet switched facilities as well as distributed information processing units handling new text communication services are part of future integrated services digital networks. The functional integration of text communicaton procedures with the digital network is discussed. Unified handling of batch and interactive text communications is proposed. The use of standardized protocols at both transport and user service levels is suggested. The implementation of transport service layered functions into actual hierarchical communication levels is examined. It is shown possible to define standardized protocols common to both circuit switched and packet switched operating facilities. The text communication functions pertaining to session and presentation tasks are described. A session protocol common to both batch and interactive services is envisaged and real as well as virtual presentation services are considered.

  8. Computing, Information and Communications Technology (CICT) Website

    NASA Technical Reports Server (NTRS)

    Hardman, John; Tu, Eugene (Technical Monitor)

    2002-01-01

    The Computing, Information and Communications Technology Program (CICT) was established in 2001 to ensure NASA's Continuing leadership in emerging technologies. It is a coordinated, Agency-wide effort to develop and deploy key enabling technologies for a broad range of mission-critical tasks. The NASA CICT program is designed to address Agency-specific computing, information, and communications technology requirements beyond the projected capabilities of commercially available solutions. The areas of technical focus have been chosen for their impact on NASA's missions, their national importance, and the technical challenge they provide to the Program. In order to meet its objectives, the CICT Program is organized into the following four technology focused projects: 1) Computing, Networking and Information Systems (CNIS); 2) Intelligent Systems (IS); 3) Space Communications (SC); 4) Information Technology Strategic Research (ITSR).

  9. Network and Index Coding with Application to Robust and Secure Communications 

    E-print Network

    El Rouayheb, Salim Y.

    2011-02-22

    Since its introduction in the year 2000 by Ahlswede et al., the network coding paradigm has revolutionized the way we understand information flows in networks. Traditionally, information transmitted in a communication network was treated as a...

  10. LONG-DISTANCE WIRELESS NETWORKING FOR SITE - OFFICE DATA COMMUNICATIONS

    Microsoft Academic Search

    Ioannis K. Brilakis

    2007-01-01

    SUMMARY: Effective data communications between the project site and decision making office can be critical for the success of a construction project. It allows convenient access to centrally stored information and allows centrally located decision makers to remotely monitor the site and collect data in real-time. However, high bandwidth, flexible data communication networks, such as wired local area networks, can

  11. Adoption of information and communication technology (ICT) in academic libraries: A strategy for library networking in Nigeria

    Microsoft Academic Search

    Okon E. Ani; Jacob E. Esin; Nkoyo Edem

    2005-01-01

    Purpose – This study aims to investigate the extent of adoption of information and communication technology (ICT) in university libraries in Nigeria. Design\\/methodology\\/approach – Postal survey was the instrument used for data collection. Almost 60 per cent of the University Librarians out of the 29 university libraries surveyed completed their questionnaires. Findings – The results of the survey show that

  12. 77 FR 36305 - Stream Communications Network & Media, Inc.; Order of Suspension of Trading

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-18

    ...SECURITIES AND EXCHANGE COMMISSION...Stream Communications Network & Media, Inc...It appears to the Securities and Exchange Commission...information concerning the securities of Stream Communications Network & Media, Inc....

  13. Network Distributed POMDP with Communication

    Microsoft Academic Search

    Yuki Iwanari; Yuichi Yabu; Makoto Tasaki; Makoto Yokoo

    2008-01-01

    While Distributed POMDPs have become popular for modeling multiagent systems in uncertain domains, it is the Network Distributed\\u000a POMDPs (ND-POMDPs) model that has begun to scale-up the number of agents. The ND-POMDPs can utilize the locality in agents’\\u000a interactions. However, prior work in ND-POMDPs has failed to address communication. Without communication, the size of a local\\u000a policy at each agent

  14. The Geospatial Characteristics of a Social Movement Communication Network

    E-print Network

    Conover, Michael D; Ferrara, Emilio; McKelvey, Karissa; Menczer, Filippo; Flammini, Alessandro

    2013-01-01

    Social movements rely in large measure on networked communication technologies to organize and disseminate information relating to the movements' objectives. In this work we seek to understand how the goals and needs of a protest movement are reflected in the geographic patterns of its communication network, and how these patterns differ from those of stable political communication. To this end, we examine an online communication network reconstructed from over 600,000 tweets from a thirty-six week period covering the birth and maturation of the American anticapitalist movement, Occupy Wall Street. We find that, compared to a network of stable domestic political communication, the Occupy Wall Street network exhibits higher levels of locality and a hub and spoke structure, in which the majority of non-local attention is allocated to high-profile locations such as New York, California, and Washington D.C. Moreover, we observe that information flows across state boundaries are more likely to contain framing lang...

  15. Flow of affective information between communicating brains

    PubMed Central

    Anders, Silke; Heinzle, Jakob; Weiskopf, Nikolaus; Ethofer, Thomas; Haynes, John-Dylan

    2011-01-01

    When people interact, affective information is transmitted between their brains. Modern imaging techniques permit to investigate the dynamics of this brain-to-brain transfer of information. Here, we used information-based functional magnetic resonance imaging (fMRI) to investigate the flow of affective information between the brains of senders and perceivers engaged in ongoing facial communication of affect. We found that the level of neural activity within a distributed network of the perceiver's brain can be successfully predicted from the neural activity in the same network in the sender's brain, depending on the affect that is currently being communicated. Furthermore, there was a temporal succession in the flow of affective information from the sender's brain to the perceiver's brain, with information in the perceiver's brain being significantly delayed relative to information in the sender's brain. This delay decreased over time, possibly reflecting some ‘tuning in’ of the perceiver with the sender. Our data support current theories of intersubjectivity by providing direct evidence that during ongoing facial communication a ‘shared space’ of affect is successively built up between senders and perceivers of affective facial signals. PMID:20624471

  16. Reinforced communication and social navigation generate groups in model networks.

    PubMed

    Rosvall, M; Sneppen, K

    2009-02-01

    To investigate the role of information flow in group formation, we introduce a model of communication and social navigation. We let agents gather information in an idealized network society and demonstrate that heterogeneous groups can evolve without presuming that individuals have different interests. In our scenario, individuals' access to global information is constrained by local communication with the nearest neighbors on a dynamic network. The result is reinforced interests among like-minded agents in modular networks; the flow of information works as a glue that keeps individuals together. The model explains group formation in terms of limited information access and highlights global broadcasting of information as a way to counterbalance this fragmentation. To illustrate how the information constraints imposed by the communication structure affects future development of real-world systems, we extrapolate dynamics from the topology of four social networks. PMID:19391810

  17. Communication in automation, including networking and wireless

    E-print Network

    Antsaklis, Panos

    Communication in automation, including networking and wireless Nicholas Kottenstette and Panos J and networking in automation is given. Digital communication fundamentals are reviewed and networked control are presented. 1 Introduction 1.1 Why communication is necessary in automated systems Automated systems use

  18. Northwestern University Information Technology Building Infrastructure Requirements for Communication Facilities

    E-print Network

    Shahriar, Selim

    Northwestern University Information Technology Building Infrastructure Requirements is required for any building. NUITTelecom & Network Services will consult with the FM Project Manager. Intrabuilding communications cabling shall be provided, connecting the building Intermediate Distribution Frame

  19. Network-Centric Quantum Communications

    NASA Astrophysics Data System (ADS)

    Hughes, Richard

    2014-03-01

    Single-photon quantum communications (QC) offers ``future-proof'' cryptographic security rooted in the laws of physics. Today's quantum-secured communications cannot be compromised by unanticipated future technological advances. But to date, QC has only existed in point-to-point instantiations that have limited ability to address the cyber security challenges of our increasingly networked world. In my talk I will describe a fundamentally new paradigm of network-centric quantum communications (NQC) that leverages the network to bring scalable, QC-based security to user groups that may have no direct user-to-user QC connectivity. With QC links only between each of N users and a trusted network node, NQC brings quantum security to N2 user pairs, and to multi-user groups. I will describe a novel integrated photonics quantum smartcard (``QKarD'') and its operation in a multi-node NQC test bed. The QKarDs are used to implement the quantum cryptographic protocols of quantum identification, quantum key distribution and quantum secret splitting. I will explain how these cryptographic primitives are used to provide key management for encryption, authentication, and non-repudiation for user-to-user communications. My talk will conclude with a description of a recent demonstration that QC can meet both the security and quality-of-service (latency) requirements for electric grid control commands and data. These requirements cannot be met simultaneously with present-day cryptography.

  20. Information network architectures

    NASA Technical Reports Server (NTRS)

    Murray, N. D.

    1985-01-01

    Graphs, charts, diagrams and outlines of information relative to information network architectures for advanced aerospace missions, such as the Space Station, are presented. Local area information networks are considered a likely technology solution. The principle needs for the network are listed.

  1. Weather Information Communications (WINCOMM) Overview and Status

    NASA Technical Reports Server (NTRS)

    Martzaklis, K.

    2003-01-01

    The second annual project review of Weather Information Communications (WINCOMM) is presented. The topics of discussion include: 1) In-Flight Weather Information; 2) System Elements; 3) Technology Investment Areas; 4) NAS Information Exchange; 5) FIS Datalink Architecture Analyses; 6) Hybrid FIS Datalink Architecture; 7) FIS Datalink Architecture Analyses; 8) Air Transport: Ground and Satellite-based Datalinks; 9) General Aviation: Ground and Satellite-based Datalinks; 10) Low Altitude AutoMET Reporting; 11) AutoMET: Airborne-based Datalinks; 12) Network Protocols Development; and 13) FAA/NASA Collaboration. A summary of WINCOMM is also included. This paper is in viewgraph form.

  2. Information and Communications Technologies (ICT) Center Print Publications

    NSDL National Science Digital Library

    This website from the Information and Communication Technology (ICT) Center provides a list of print publications from the ICT Center Delmar Learning Series, created by Delmar Learning and the ICT Center. Titles include Introduction to Telecommunications Networks, Basic Telecommunications: The Physical Layer, Fiber Optic Communications and Network Security. The listings for each book include links to information and sample chapters on Delmar Learning's website, as well as links to order the titles on Amazon.com.

  3. Communication devices for network-hopping communications and methods of network-hopping communications

    DOEpatents

    Buttles, John W

    2013-04-23

    Wireless communication devices include a software-defined radio coupled to processing circuitry. The system controller is configured to execute computer programming code. Storage media is coupled to the system controller and includes computer programming code configured to cause the system controller to configure and reconfigure the software-defined radio to operate on each of a plurality of communication networks according to a selected sequence. Methods for communicating with a wireless device and methods of wireless network-hopping are also disclosed.

  4. Communication devices for network-hopping communications and methods of network-hopping communications

    DOEpatents

    Buttles, John W. (Idaho Falls, ID)

    2011-12-20

    Wireless communication devices include a software-defined radio coupled to processing circuitry. The processing circuitry is configured to execute computer programming code. Storage media is coupled to the processing circuitry and includes computer programming code configured to cause the processing circuitry to configure and reconfigure the software-defined radio to operate on each of a plurality of communication networks according to a selected sequence. Methods for communicating with a wireless device and methods of wireless network-hopping are also disclosed.

  5. Communication via Quantum Neural Network

    E-print Network

    Segher, A Al-

    2009-01-01

    In this study, the partially entangled neural networks is used to transfer information between two neurons, where the original teleportation protocol is employed this for this purpose. The effect of the network strength on the fidelity of the transported information is investigated. We show that as the strength of the network increases, the accuracy of the transformed information increases. As a practical application, we consider the spread of swine flu virus between two equivalent tranches of the community. In this treatment two factors are considered, one for humanity and the other for influence factor. The likelihood of infection between different age group is investigated, where we show that the strength of the neural network and the degree of infection plays an important role on transferring infection between different age group. From theoretical point of view, we show that it is possible to control the spread of the virus by controlling the network parameter. Also, by using local rotation, one can decre...

  6. Covert Communication Networks 

    E-print Network

    Nix, Timothy Glen

    2013-08-02

    . . . . . . . . . . . . . . . . . . . . . . . . . . . 136 9.5 The Application Layer . . . . . . . . . . . . . . . . . . . . . . . . . . 137 9.5.1 File Sharing . . . . . . . . . . . . . . . . . . . . . . . . . . . . 137 9.5.2 VoIP and VTC . . . . . . . . . . . . . . . . . . . . . . . . . . 137 9... and correlate tra c across large portions of the net- work or pressure ISPs to map IP addresses to real-word identities. Examples of such groups include so-called insurgencies and resistance movements [32] where a number of agents operate and communicate...

  7. Communications for unattended sensor networks

    NASA Astrophysics Data System (ADS)

    Nemeroff, Jay L.; Angelini, Paul; Orpilla, Mont; Garcia, Luis; DiPierro, Stefano

    2004-07-01

    The future model of the US Army's Future Combat Systems (FCS) and the Future Force reflects a combat force that utilizes lighter armor protection than the current standard. Survival on the future battlefield will be increased by the use of advanced situational awareness provided by unattended tactical and urban sensors that detect, identify, and track enemy targets and threats. Successful implementation of these critical sensor fields requires the development of advanced sensors, sensor and data-fusion processors, and a specialized communications network. To ensure warfighter and asset survivability, the communications must be capable of near real-time dissemination of the sensor data using robust, secure, stealthy, and jam resistant links so that the proper and decisive action can be taken. Communications will be provided to a wide-array of mission-specific sensors that are capable of processing data from acoustic, magnetic, seismic, and/or Chemical, Biological, Radiological, and Nuclear (CBRN) sensors. Other, more powerful, sensor node configurations will be capable of fusing sensor data and intelligently collect and process data images from infrared or visual imaging cameras. The radio waveform and networking protocols being developed under the Soldier Level Integrated Communications Environment (SLICE) Soldier Radio Waveform (SRW) and the Networked Sensors for the Future Force Advanced Technology Demonstration are part of an effort to develop a common waveform family which will operate across multiple tactical domains including dismounted soldiers, ground sensor, munitions, missiles and robotics. These waveform technologies will ultimately be transitioned to the JTRS library, specifically the Cluster 5 requirement.

  8. VSAT communications networks - An overview

    NASA Astrophysics Data System (ADS)

    Chakraborty, D.

    1988-05-01

    The very-small-aperture-terminal (VSAT) fixed satellite communication network is a star network in which many dispersed micro terminals attempt to send data in a packet form through a random access/time-division multiple-access (RA/TDMA) satellite channel with transmission delay. The basic concept of the VSAT and its service potential are discussed. Two classes of traffic are addressed, namely, business-oriented low-rate-data traffic and bulk data traffic of corporate networks. Satellite access, throughput, and delay are considered. The size of the network population that can be served in an RA/TDMA environment is calculated. User protocols are examined. A typical VSAT business scenario is described.

  9. Communication through Resonance in Spiking Neuronal Networks

    PubMed Central

    Frégnac, Yves; Aertsen, Ad; Kumar, Arvind

    2014-01-01

    The cortex processes stimuli through a distributed network of specialized brain areas. This processing requires mechanisms that can route neuronal activity across weakly connected cortical regions. Routing models proposed thus far are either limited to propagation of spiking activity across strongly connected networks or require distinct mechanisms that create local oscillations and establish their coherence between distant cortical areas. Here, we propose a novel mechanism which explains how synchronous spiking activity propagates across weakly connected brain areas supported by oscillations. In our model, oscillatory activity unleashes network resonance that amplifies feeble synchronous signals and promotes their propagation along weak connections (“communication through resonance”). The emergence of coherent oscillations is a natural consequence of synchronous activity propagation and therefore the assumption of different mechanisms that create oscillations and provide coherence is not necessary. Moreover, the phase-locking of oscillations is a side effect of communication rather than its requirement. Finally, we show how the state of ongoing activity could affect the communication through resonance and propose that modulations of the ongoing activity state could influence information processing in distributed cortical networks. PMID:25165853

  10. Competition in Communication Networks: Pricing and Regulation

    Microsoft Academic Search

    Robin Mason; Tommaso M. Valletti

    2001-01-01

    By any measure, the communication sector is important. It is no surprise, then, that the communication sector has attracted the attention of both policy-makers and economists. In this paper, we argue that four characteristics of the networks that deliver communication services make this area of particular interest. We analyse the implications of networks' cost structures; the strong complementarity between their

  11. Impulse Ultrawideband ad-hoc tracking and communication network

    Microsoft Academic Search

    Farshad Kheiri; B. Dewberryy; Artur Jackson; Laurie L. Joiner

    2008-01-01

    We propose a new dispersing protocol for mobile radios equipped with impulse-ultra wideband (IUWB) communication tools. Our network supports communication and ranging between mobile nodes localized at a central base station. The mobile radios are autonomous and make independent decisions based on the information they receive from other radios. Their decision for the direction they move should support their connectivity

  12. Improved Upper Bound on -Time-Relaxed -Broadcasting Communication Networks

    E-print Network

    Averbuch, Amir

    1 Improved Upper Bound on -Time-Relaxed -Broadcasting Communication Networks A. Averbuch I. Peeri Y communication link between these vertices. Then, we de£ne broadcasting from a vertex ¨ (the originator@post.tau.ac.il Abstract Broadcasting is a process in which an individual has an item of information which needs

  13. Coding and control for communication networks

    Microsoft Academic Search

    Wei Chen; Danail Traskov; Michael Heindlmaier; Muriel Médard; Sean P. Meyn; Asuman E. Ozdaglar

    2009-01-01

    The purpose of this paper is to survey techniques for constructing effective policies for controlling complex networks, and to extend these techniques to cap- ture special features of wireless communication networks under different networking scenarios. Among the key questions addressed are: (i) The relationship between static network equilibria, and dynamic network con- trol. (ii) The effect of coding on control

  14. Multihop communications in future mobile radio networks

    Microsoft Academic Search

    H. Li; M. Lott; M. Weckerle; W. Zirwas; E. Schulz

    2002-01-01

    Cellular networks and wireless local area networks (WLAN) are being widely deployed for mobile radio communications. Taking into account the advantageous and drawbacks of both network architectures, it becomes obvious that a combination of them is the logical consequence for future mobile radio networks. The scope of this paper is to introduce a future radio network architecture called hierarchical multihop

  15. Networked UAV Command, Control and Communication

    E-print Network

    Frew, Eric W.

    Networked UAV Command, Control and Communication Jack Elston , Eric Frew , Brian Argrow University of Colorado, Boulder, CO, 80309, USA The networked UAV command, control, and communication project for UAVs. The system utilizes an existing ad-hoc network to demonstrate the ability of UAVs to make mission

  16. An Adaptive Neural Network guided Random Block Length based Cryptosystem for online wireless communication (ANNRBLC)

    Microsoft Academic Search

    J. K. Mandal; Arindam Sarkar

    2011-01-01

    In this paper an Adaptive Neural Network guided Random Block Length based Cryptosystem (ANNRBLC) has been proposed for online transmission of data\\/information through wireless communication. Both communicating networks receive an identical input vector, generate an output bit, networks are trained based on the bit, and as a result of this dynamics through adaptive weight vectors the networks synchronize to an

  17. On traffic analysis in anonymous communication networks

    E-print Network

    Zhu, Ye

    2009-06-02

    In this dissertation, we address issues related to traffic analysis attacks and the engineering in anonymous communication networks. Mixes have been used in many anonymous communication systems and are supposed to provide countermeasures that can...

  18. Communications network design and costing model users manual

    NASA Technical Reports Server (NTRS)

    Logan, K. P.; Somes, S. S.; Clark, C. A.

    1983-01-01

    The information and procedures needed to exercise the communications network design and costing model for performing network analysis are presented. Specific procedures are included for executing the model on the NASA Lewis Research Center IBM 3033 computer. The concepts, functions, and data bases relating to the model are described. Model parameters and their format specifications for running the model are detailed.

  19. Optimized Flow Allocation for Anonymous Communication in Multipath Wireless Networks

    E-print Network

    Poovendran, Radha

    Optimized Flow Allocation for Anonymous Communication in Multipath Wireless Networks Chouchang Yang Arabia Abstract--In anonymous networks, a subset of nodes is chosen to act as covert relays to hide timing information from unau- thorized observers. While such covert relays increase anonymity, they cause

  20. Coding and Control for Communication Networks

    E-print Network

    Medard, Muriel

    The purpose of this paper is to survey techniques for constructing effective policies for controlling complex networks, and to extend these techniques to capture special features of wireless communication networks under ...

  1. Distributed Resource Allocation in Communication Networks

    E-print Network

    Huang, Jianwei

    (Princeton University) Distributed Resource Allocation Jan. 2007 1 / 60 #12;Acknowledgement Academia-Wei Tan, Jeffrey Dwoskin Northwestern University: Michael Honig, Randall Berry, Aggelos Katsaggelos Resource Allocation Jan. 2007 2 / 60 #12;Communication Networks Are Everywhere ... SGSN Internal Network

  2. Anomaly Detection Approaches for Communication Networks

    E-print Network

    Ji, Chuanyi

    Anomaly Detection Approaches for Communication Networks Marina Thottan, Guanglei Liu, Chuanyi Ji Abstract In recent years network anomaly detection has become an important area for both commercial interests as well as academic research. Applications of anomaly detection typically stem from

  3. COMMUNICATION (European Clinical Research Infrastructures Network)

    E-print Network

    Paris-Sud XI, Université de

    COMMUNICATION ECRIN (European Clinical Research Infrastructures Network) et la structuration de la recherche clinique en Europe Mots clés : Recherche biomédicale. Europe ECRIN (European Clinical Research Infrastructures Network), a pan-european infrastructure for clinical research Key-words (Index medicus

  4. PIPELINES AS COMMUNICATION NETWORK LINKS

    SciTech Connect

    Kelvin T. Erickson; Ann Miller; E. Keith Stanek; C.H. Wu; Shari Dunn-Norman

    2005-03-14

    This report presents the results of an investigation into two methods of using the natural gas pipeline as a communication medium. The work addressed the need to develop secure system monitoring and control techniques between the field and control centers and to robotic devices in the pipeline. In the first method, the pipeline was treated as a microwave waveguide. In the second method, the pipe was treated as a leaky feeder or a multi-ground neutral and the signal was directly injected onto the metal pipe. These methods were tested on existing pipeline loops at UMR and Batelle. The results reported in this report indicate the feasibility of both methods. In addition, a few suitable communication link protocols for this network were analyzed.

  5. Communication via Quantum Neural Network

    E-print Network

    A. Al- Segher; Nasser Metwally

    2009-12-13

    In this study, the partially entangled neural networks is used to transfer information between two neurons, where the original teleportation protocol is employed this for this purpose. The effect of the network strength on the fidelity of the transported information is investigated. We show that as the strength of the network increases, the accuracy of the transformed information increases. As a practical application, we consider the spread of swine flu virus between two equivalent tranches of the community. In this treatment two factors are considered, one for humanity and the other for influence factor. The likelihood of infection between different age group is investigated, where we show that the strength of the neural network and the degree of infection plays an important role on transferring infection between different age group. From theoretical point of view, we show that it is possible to control the spread of the virus by controlling the network parameter. Also, by using local rotation, one can decrease the rate of infection between the young.

  6. Performance studies of Low Earth Orbit Satellite (LEOS) communication networks for global communications

    SciTech Connect

    Raines, R.A.; Janoso, R.F.; Stenger, D.K. [Department of Electrical and Computer Engineering Air Force Institute of Technology Wright-Patterson AFB, Ohio45433-7765 (United States)

    1997-01-01

    Communicating appropriate information to desired destinations is of critical importance to the Air Force and the Department of Defense (DoD). The communications infrastructure used to provide this information must be reliable and also efficient in terms of minimizing delay. Additionally, {open_quotes}anytime and anywhere{close_quotes} communication capabilities are desired of the infrastructure. In order to provide global communications, satellite communication systems must be used for primary as well as supplemental communication mediums. Satellite communication systems can be used to provide the infrastructure with the {open_quotes}anytime and anywhere{close_quotes} capability. Recent advances in microelectronic and cellular radio technologies have allowed for the proposed implementation of low earth orbit satellite (LEOS) communication networks for global personal communications. This paper examines the performance of LEOS networks in a packet-switched environment. Performance is defined here in terms of link availability and reliability in a faulty environment. An overview of LEOS systems is provided, as well as critical issues associated with the implementation of such a system. To illustrate the nature of LEOS network communications, the commercially proposed system Iridium is examined. {copyright} {ital 1997 American Institute of Physics.}

  7. PESTICIDE INFORMATION NETWORK

    EPA Science Inventory

    The Pesticide Information Network (PIN) is an interactive database containing information about pesticides. PIN is a free service offered by the USEPAs Office of Pesticide Programs which provides contacts on pesticide issues, has a bulletin board network for public and private us...

  8. Exponential Separation of Information and Communication

    E-print Network

    Raz, Ran

    Exponential Separation of Information and Communication Anat Ganor Gillat Kol Ran Raz Abstract We show an exponential gap between communication complexity and information complexity, by giving an explicit example for a communication task (relation), with information complexity O(k), and distributional

  9. Environmental effects of information and communications technologies.

    PubMed

    Williams, Eric

    2011-11-17

    The digital revolution affects the environment on several levels. Most directly, information and communications technology (ICT) has environmental impacts through the manufacturing, operation and disposal of devices and network equipment, but it also provides ways to mitigate energy use, for example through smart buildings and teleworking. At a broader system level, ICTs influence economic growth and bring about technological and societal change. Managing the direct impacts of ICTs is more complex than just producing efficient devices, owing to the energetically expensive manufacturing process, and the increasing proliferation of devices needs to be taken into account. PMID:22094696

  10. Wireless Communication and Broadcasting Convergence Network Throughput

    Microsoft Academic Search

    Bo Bai; Zhigang Cao; Wei Chen; I Chih-Lin

    2009-01-01

    Wireless communication and broadcasting convergence networks provide a potential solution to greater traffic throughput in the future. In this paper, the throughput of a convergence network is analyzed based on the standardization project for specific requirements for local and metropolitan area networks in China, referred to as broadband wireless multimedia systems. The convergence network is modeled as a combination of

  11. A Security Architecture for Health Information Networks

    PubMed Central

    Kailar, Rajashekar

    2007-01-01

    Health information network security needs to balance exacting security controls with practicality, and ease of implementation in today’s healthcare enterprise. Recent work on ‘nationwide health information network’ architectures has sought to share highly confidential data over insecure networks such as the Internet. Using basic patterns of health network data flow and trust models to support secure communication between network nodes, we abstract network security requirements to a core set to enable secure inter-network data sharing. We propose a minimum set of security controls that can be implemented without needing major new technologies, but yet realize network security and privacy goals of confidentiality, integrity and availability. This framework combines a set of technology mechanisms with environmental controls, and is shown to be sufficient to counter commonly encountered network security threats adequately. PMID:18693862

  12. A security architecture for health information networks.

    PubMed

    Kailar, Rajashekar; Muralidhar, Vinod

    2007-01-01

    Health information network security needs to balance exacting security controls with practicality, and ease of implementation in today's healthcare enterprise. Recent work on 'nationwide health information network' architectures has sought to share highly confidential data over insecure networks such as the Internet. Using basic patterns of health network data flow and trust models to support secure communication between network nodes, we abstract network security requirements to a core set to enable secure inter-network data sharing. We propose a minimum set of security controls that can be implemented without needing major new technologies, but yet realize network security and privacy goals of confidentiality, integrity and availability. This framework combines a set of technology mechanisms with environmental controls, and is shown to be sufficient to counter commonly encountered network security threats adequately. PMID:18693862

  13. Communication Network Design: West Ottawa School District.

    ERIC Educational Resources Information Center

    Couch, David deS.

    This report describes the technical details and rationale behind the decisions in the design and development of the communications network installed as part of a 1991-1993 district-wide construction project in the West Ottawa Public Schools (Michigan). The project called for development of a communications network to carry voice, data, and video…

  14. Local Experts in the Domestication of Information and Communication Technologies

    Microsoft Academic Search

    James Stewart

    2007-01-01

    Research into the adoption and use of new Information and Communication Technologies (ICTs) pays increasing attention to social context; however, the social fabric of contexts of use is often poorly theorized. This paper presents an investigation into the formation and operation of informal local networks of collaboration and knowledge exchange. It highlights the role of local experts in sustaining these

  15. Scalable Hierarchical Network Management System for Displaying Network Information in Three Dimensions

    NASA Technical Reports Server (NTRS)

    George, Jude (Inventor); Schlecht, Leslie (Inventor); McCabe, James D. (Inventor); LeKashman, John Jr. (Inventor)

    1998-01-01

    A network management system has SNMP agents distributed at one or more sites, an input output module at each site, and a server module located at a selected site for communicating with input output modules, each of which is configured for both SNMP and HNMP communications. The server module is configured exclusively for HNMP communications, and it communicates with each input output module according to the HNMP. Non-iconified, informationally complete views are provided of network elements to aid in network management.

  16. The National Biomedical Communications Network as a Developing Structure *

    PubMed Central

    Davis, Ruth M.

    1971-01-01

    The National Biomedical Communications Network has evolved both from a set of conceptual recommendations over the last twelve years and an accumulation of needs manifesting themselves in the requests of members of the medical community. With a short history of three years this network and its developing structure have exhibited most of the stresses of technology interfacing with customer groups, and of a structure attempting to build itself upon many existing fragmentary unconnected segments of a potentially viable resourcesharing capability. In addition to addressing these topics, the paper treats a design appropriate to any network devoted to information transfer in a special interest user community. It discusses fundamentals of network design, highlighting that network structure most appropriate to a national information network. Examples are given of cost analyses of information services and certain conjectures are offered concerning the roles of national networks. PMID:5542912

  17. Effective Protocols for Mobile Communications and Networking

    SciTech Connect

    Espinoza, J.; Sholander, P.; Van Leeuwen, B,

    1998-12-01

    This report examines methods of mobile communications with an emphasis on mobile computing and wireless communications. Many of the advances in communications involve the use of Internet Protocol (IP), Asynchronous Transfer Mode (ATM), and ad hoc network protocols. However, many of the advances in these protocols have been focused on wired communications. Recently much focus has been directed at advancing communication technology in the area of mobile wireless networks. This report discusses various protocols used in mobile communications and proposes a number of extensions to existing protocols. A detailed discussion is also included on desirable protocol characteristics and evaluation criteria. In addition, the report includes a discussion on several network simulation tools that maybe used to evaluate network protocols.

  18. Validation of Network Communicability Metrics for the Analysis of Brain Structural Networks

    PubMed Central

    Andreotti, Jennifer; Jann, Kay; Melie-Garcia, Lester; Giezendanner, Stéphanie; Abela, Eugenio; Wiest, Roland; Dierks, Thomas; Federspiel, Andrea

    2014-01-01

    Computational network analysis provides new methods to analyze the brain's structural organization based on diffusion imaging tractography data. Networks are characterized by global and local metrics that have recently given promising insights into diagnosis and the further understanding of psychiatric and neurologic disorders. Most of these metrics are based on the idea that information in a network flows along the shortest paths. In contrast to this notion, communicability is a broader measure of connectivity which assumes that information could flow along all possible paths between two nodes. In our work, the features of network metrics related to communicability were explored for the first time in the healthy structural brain network. In addition, the sensitivity of such metrics was analysed using simulated lesions to specific nodes and network connections. Results showed advantages of communicability over conventional metrics in detecting densely connected nodes as well as subsets of nodes vulnerable to lesions. In addition, communicability centrality was shown to be widely affected by the lesions and the changes were negatively correlated with the distance from lesion site. In summary, our analysis suggests that communicability metrics that may provide an insight into the integrative properties of the structural brain network and that these metrics may be useful for the analysis of brain networks in the presence of lesions. Nevertheless, the interpretation of communicability is not straightforward; hence these metrics should be used as a supplement to the more standard connectivity network metrics. PMID:25549088

  19. Wireless Communications and Networking Technologies for Smart Grid: Paradigms and Challenges

    E-print Network

    Fang, Xi; Xue, Guoliang

    2011-01-01

    Smart grid, regarded as the next generation power grid, uses two-way flows of electricity and information to create a widely distributed automated energy delivery network. In this work we present our vision on smart grid from the perspective of wireless communications and networking technologies. We present wireless communication and networking paradigms for four typical scenarios in the future smart grid and also point out the research challenges of the wireless communication and networking technologies used in smart grid

  20. Extracting Association Patterns in Network Communications

    PubMed Central

    Portela, Javier; Villalba, Luis Javier García; Trujillo, Alejandra Guadalupe Silva; Orozco, Ana Lucila Sandoval; Kim, Tai-hoon

    2015-01-01

    In network communications, mixes provide protection against observers hiding the appearance of messages, patterns, length and links between senders and receivers. Statistical disclosure attacks aim to reveal the identity of senders and receivers in a communication network setting when it is protected by standard techniques based on mixes. This work aims to develop a global statistical disclosure attack to detect relationships between users. The only information used by the attacker is the number of messages sent and received by each user for each round, the batch of messages grouped by the anonymity system. A new modeling framework based on contingency tables is used. The assumptions are more flexible than those used in the literature, allowing to apply the method to multiple situations automatically, such as email data or social networks data. A classification scheme based on combinatoric solutions of the space of rounds retrieved is developed. Solutions about relationships between users are provided for all pairs of users simultaneously, since the dependence of the data retrieved needs to be addressed in a global sense. PMID:25679311

  1. EECE 569 -UBC ECE -Outline Outline-1 Mobile Communications Networks

    E-print Network

    Pulfrey, David L.

    Wireless wireline interworking Mobile IP Simulations of wireless networks Security in wireless networksEECE 569 - UBC ECE - Outline Outline-1 EECE 569 Mobile Communications Networks http Objectives Aspects of mobile communications networks Architectures, protocols and management techniques

  2. Watermarking as communications with side information

    Microsoft Academic Search

    Ingemar J. Cox; MATTHEW L. MILLER; Andrew L. McKellips

    1999-01-01

    Several authors have drawn comparison between embedded signaling or watermarking and communications, especially spread-spectrum communications. We examine the similarities and differences between watermarking and traditional communications. This comparison suggests that watermarking most closely resembles communications with side information at the transmitter and or detector, a configuration originally described by Shannon (1958). This leads to several novel characteristics and insights regarding

  3. Economical Quantum Secure Direct Communication Network with Single Photons

    E-print Network

    Fu-Guo Deng; Xi-Han Li; Chun-Yan Li; Ping Zhou; Hong-Yu Zhou

    2007-12-13

    A scheme for quantum secure direct communication (QSDC) network is proposed with a sequence of polarized single photons. The single photons are prepared originally in the same state |0> by the servers on the network, which will reduce the difficulty for the legitimate users to check eavesdropping largely. The users code the information on the single photons with two unitary operations which do not change their measuring bases. Some decoy photons, which are produced by operating the sample photons with a Hadamard, are used for preventing a potentially dishonest server from eavesdropping the quantum lines freely. This scheme is an economical one as it is the easiest way for QSDC network communication securely.

  4. Great Lakes Information Network

    NSDL National Science Digital Library

    The Great Lakes Information Network (GLIN) is a partnership that has compiled information relating to the binational Great Lakes-St. Lawrence region of North America. Sections of the site include an overview of the Great Lakes, the environment of the Great Lakes, the economy of the Great Lakes, education, maps and Geographic Information Systems (GIS), and tourism.

  5. Child Rights Information Network Newsletter, 1997.

    ERIC Educational Resources Information Center

    Purbrick, Becky, Ed.

    1997-01-01

    These three newsletter issues communicate activities of the Child Rights Information Network (CRIN) and report on information resources and worldwide activities concerning children and child rights. The January 1997 issue profiles CRIN members in Costa Rica, Tanzania, Germany, and Switzerland; and provides updates on the activities of projects…

  6. Child Rights Information Network Newsletter, 1996.

    ERIC Educational Resources Information Center

    Purbrick, Becky, Ed.

    1996-01-01

    These two newsletter issues communicate activities of the newly formed Child Rights Information Network (CRIN) and report on emerging information resources and activities concerning children and child rights. The January 1996 issue describes the history of CRIN, provides updates on the activities of projects linked to CRIN, and summarizes…

  7. The geospatial characteristics of a social movement communication network.

    PubMed

    Conover, Michael D; Davis, Clayton; Ferrara, Emilio; McKelvey, Karissa; Menczer, Filippo; Flammini, Alessandro

    2013-01-01

    Social movements rely in large measure on networked communication technologies to organize and disseminate information relating to the movements' objectives. In this work we seek to understand how the goals and needs of a protest movement are reflected in the geographic patterns of its communication network, and how these patterns differ from those of stable political communication. To this end, we examine an online communication network reconstructed from over 600,000 tweets from a thirty-six week period covering the birth and maturation of the American anticapitalist movement, Occupy Wall Street. We find that, compared to a network of stable domestic political communication, the Occupy Wall Street network exhibits higher levels of locality and a hub and spoke structure, in which the majority of non-local attention is allocated to high-profile locations such as New York, California, and Washington D.C. Moreover, we observe that information flows across state boundaries are more likely to contain framing language and references to the media, while communication among individuals in the same state is more likely to reference protest action and specific places and times. Tying these results to social movement theory, we propose that these features reflect the movement's efforts to mobilize resources at the local level and to develop narrative frames that reinforce collective purpose at the national level. PMID:23483885

  8. Internetworking satellite and local exchange networks for personal communications applications

    NASA Technical Reports Server (NTRS)

    Wolff, Richard S.; Pinck, Deborah

    1993-01-01

    The demand for personal communications services has shown unprecedented growth, and the next decade and beyond promise an era in which the needs for ubiquitous, transparent and personalized access to information will continue to expand in both scale and scope. The exchange of personalized information is growing from two-way voice to include data communications, electronic messaging and information services, image transfer, video, and interactive multimedia. The emergence of new land-based and satellite-based wireless networks illustrates the expanding scale and trend toward globalization and the need to establish new local exchange and exchange access services to meet the communications needs of people on the move. An important issue is to identify the roles that satellite networking can play in meeting these new communications needs. The unique capabilities of satellites, in providing coverage to large geographic areas, reaching widely dispersed users, for position location determination, and in offering broadcast and multicast services, can complement and extend the capabilities of terrestrial networks. As an initial step in exploring the opportunities afforded by the merger of satellite-based and land-based networks, several experiments utilizing the NASA ACTS satellite and the public switched local exchange network were undertaken to demonstrate the use of satellites in the delivery of personal communications services.

  9. Research on the key techniques of wireless communication for emergency information system

    Microsoft Academic Search

    Zhigang Yang

    2010-01-01

    As China's continuous improvement in the degree of information, the wireless communication network has covered all regions of the country, and information has also brought a great deal of information network security issues. In this paper, firstly, the information security emergency response procedures and disposal system are proposed according to the comprehensive analysis of weak links in information security defense

  10. Modeling data throughput on communication networks

    SciTech Connect

    Eldridge, J.M.

    1993-11-01

    New challenges in high performance computing and communications are driving the need for fast, geographically distributed networks. Applications such as modeling physical phenomena, interactive visualization, large data set transfers, and distributed supercomputing require high performance networking [St89][Ra92][Ca92]. One measure of a communication network`s performance is the time it takes to complete a task -- such as transferring a data file or displaying a graphics image on a remote monitor. Throughput, defined as the ratio of the number of useful data bits transmitted per the time required to transmit those bits, is a useful gauge of how well a communication system meets this performance measure. This paper develops and describes an analytical model of throughput. The model is a tool network designers can use to predict network throughput. It also provides insight into those parts of the network that act as a performance bottleneck.

  11. Earth System Science Informal Education Network (ESSIEN)

    NSDL National Science Digital Library

    The Earth System Science Informal Education Network (ESSIEN) is dedicated to improving Earth system literacy through increased communication and collaboration among providers of informal Earth system education. The collection is designed for museum professionals (educators, exhibits designers, developers) as a resource of ideas, tools, traveling exhibits and online materials. The resources are web portals to organizations providing substantial informal Earth system science education. They describe educational programming, resources and exhibits that are pertinent to an informal educator.

  12. Communication Stack Customization for Wireless Sensor Networks

    Microsoft Academic Search

    Fadila Khadar; David Simplot-Ryl

    Communication in Wireless Sensor Networks (WSN) is a big issue. Designing an energy-efficient networking stack requires expertise, as the programmer must carefully design each layer of the stack and their interactions. This paper describes our on-going research on networking stack cus- tomization for WSN. We present an architecture which aims at simplifying the process of building an application by pro-

  13. ICT Information Communication Technology CollegeofCommunicationandInformation

    E-print Network

    MacAdam, Keith

    ICT Information Communication Technology CollegeofCommunicationandInformation KEY: # = new course and address their information needs. (Same as IS 201.) #ICT 202 TECHNOLOGIES FOR INFORMATION SERVICES. (3. (Same as IS 202.) #ICT 205 ISSUES IN INFORMATION AND COMMUNICATION TECHNOLOGY POLICY. (3

  14. Distributed Security System for Intelligent Building Based on Wireless Communication Network

    Microsoft Academic Search

    Liting Cao; Jingwen Tian; Wei Jiang

    2006-01-01

    A distributed security system based on wireless communication technology is presented in this paper. The system adopts distributed structure, which consists of detect sensors, intelligent terminal, alarm devices and wireless communication network. The intelligent terminal which designed based on embedded system is used to realize acquisition information submitted from detect sensors, control the alarm devices and communicate the information to

  15. Multi-node processing for asymmetrical communications in underwater acoustic networks

    E-print Network

    Jesus, Sérgio M.

    to acquire environmental information, to communicate such information and to relay it from other nodes these nodes, herein designated as interface Fig. 1. Network configuration. The global node communicates with the interface nodes using a radio link. The interface nodes communicates with the underwater nodes using

  16. Interplant Communication of Tomato Plants through Underground Common Mycorrhizal Networks

    E-print Network

    Bruns, Tom

    Interplant Communication of Tomato Plants through Underground Common Mycorrhizal Networks Yuan Yuan, plants can also communicate with each other through underground common mycorrhizal networks (CMNs function as a plant-plant underground communication conduit whereby disease resistance and induced defence

  17. Energy-efficient communication in multi-interface wireless networks

    E-print Network

    Caragiannis, Ioannis

    Energy-efficient communication in multi-interface wireless networks Stavros Athanassopoulos Abstract. We study communication problems in wireless networks sup- porting multiple interfaces, energy consumption, radio interfaces, supported communication protocols, etc. Modern wireless devices

  18. Laser satellite communication network-vibration effect and possible solutions

    Microsoft Academic Search

    SHLOMI ARNON; N. S. Kopeika

    1997-01-01

    A number of serious consortiums develop satellite communication networks. The objective of these communication projects is to service personal communication users almost everywhere on Earth. The intersatellite links in those projects use microwave radiation as the carrier. Free-space optical communication between satellites networked together can make possible high-speed communication between different places on Earth. Some advantages of an optical communication

  19. Communication Reliability in Network on Chip Designs 

    E-print Network

    Kumar, Reeshav

    2012-10-19

    The performance of low latency Network on Chip (NoC) architectures, which incorporate fast bypass paths to reduce communication latency, is limited by crosstalk induced skewing of signal transitions on link wires. As a ...

  20. The Lymphoma Information Network

    NSDL National Science Digital Library

    The Lymphoma Information Network website strives to "put a bit of humanity and understanding to this disease, to gather lymphoma information and resources in one place, and to present information in an easy to understand and logical format." The award-winning site offers information sections on Hodgkin's Lymphoma, Non-Hodgkin's Lymphoma, Fighting Lymphoma, and Surviving Lymphoma. The site also offers a special resource section for kids and teenagers, and information about childhood lymphoma. In addition, the site contains an extensive Glossary of Lymphoma Terms, The Lymphoma Blog, resources for independent research, book lists, and related links.

  1. Communication as information use: insights from statistical

    E-print Network

    Stephens, David W.

    ). The category of vibratory signals comprises both near- and far-field signals, which may be produced with dedi3 Communication as information use: insights from statistical decision theory caitlin r. kight focuses on the latter, which forms the basis of animal communication. Animal communication has been

  2. Time Efficient Communication in Multi-hop Radio Networks

    E-print Network

    Xin, Qin

    Primitives in Radio Networks . . . . . . . . . . . 7 1.3.1 BroadcastingTime Efficient Communication in Multi-hop Radio Networks Thesis submitted in accordance of Liverpool October, 2004 #12;Contents 1 Introduction 1 1.1 Communication Networks

  3. Throughput Maximization in Wireless Powered Communication Networks with Energy Saving

    E-print Network

    Brown III, Donald R.

    the wireless energy broadcasted by the H-AP in the downlink. The users transmit their independent informationThroughput Maximization in Wireless Powered Communication Networks with Energy Saving Rui Wang, D access scenario where a wireless access point transmits to a group of users which harvest the energy

  4. Data Communications and Networking. Curriculum Improvement Project. Region II.

    ERIC Educational Resources Information Center

    Easter, Diane

    This course curriculum is intended for use by community college instructors and administrators in implementing a data communications networking course. A student course syllabus provides this information: credit hours, catalog description, prerequisites, required text, instructional process, objectives, student evaluation, and class schedule. A…

  5. Communicability reveals a transition to coordinated behavior in multiplex networks.

    PubMed

    Estrada, Ernesto; Gómez-Gardeñes, Jesús

    2014-04-01

    We analyze the flow of information in multiplex networks by means of the communicability function. First, we generalize this measure from its definition from simple graphs to multiplex networks. Then, we study its relevance for the analysis of real-world systems by studying a social multiplex where information flows using formal-informal channels and an air transportation system where the layers represent different air companies. Accordingly, the communicability, which is essential for the good performance of these complex systems, emerges at a systemic operation point in the multiplex where the performance of the layers operates in a coordinated way very differently from the state represented by a collection of unconnected networks. PMID:24827305

  6. Energy Harvesting Communication Networks: Optimization and Demonstration

    E-print Network

    Gesbert, David

    with the timely harvesting, storage and delivery of energy to the computing and communication units energy sources. Devices with #12;2 Fig. 2. A network of communication nodes, storage units and energy harvesting devices. EH capability can scavenge ambient energy, such as vibrations, thermal gradients or solar

  7. Multimedia Communication in Wireless Sensor Networks

    Microsoft Academic Search

    Eren G

    The technological advances in Micro Electro- Mechanical Systems (MEMS) and wireless communications have enabled the realization of wireless sensor networks (WSN) com- prised of large number of low-cost, low-power, multifunctional sensor nodes. These tiny sensor nodes communicate in short dis- tances and collaboratively work toward fulfilling the application- specific objectives of WSN. However, realization of wide range of envisioned WSN

  8. Performance indicators for wireless industrial communication networks

    Microsoft Academic Search

    Giovanni Gamba; Lucia Seno; Stefano Vitturi

    2010-01-01

    The recent improvements of the wireless networks performance offer a valuable opportunity also in the context of industrial communication systems. However, these systems are often subjected to such tight reliability requirements as well as timing constraints that wireless communications, especially in an interfered scenario, can hardly comply with. A thorough performance assessment is hence needed both at the design stage

  9. SECURITY AND COMMUNICATION NETWORKS Security Comm. Networks (2013)

    E-print Network

    2013-01-01

    SECURITY AND COMMUNICATION NETWORKS Security Comm. Networks (2013) Published online in Wiley Online, designing secure networked embedded systems is a difficult task. Model- based development (MBD) is promoted Library (wileyonlinelibrary.com). DOI: 10.1002/sec.819 SPECIAL ISSUE PAPER Integrating security mechanisms

  10. Information transfer among widely spaced individuals: latrines as a basis for communication networks in the swift fox?

    Microsoft Academic Search

    Safi K. Darden; Lise K. Steffensen; Torben Dabelsteen

    2008-01-01

    In species where individuals are widely spaced instantaneous signals cannot readily form the basis of com- munication networks, that is several individuals within signalling range of each other. However, markings, signals that remain in the environment after the signaller has left, may fulfil this role. In this study, we have investigated the possible function of swift fox, Vulpes velox, latrines,

  11. Blended Learning Networks Supported by Information and Communication Technology: An Intervention for Knowledge Transformation within Family Care of Older People

    ERIC Educational Resources Information Center

    Hanson, Elizabeth; Magnusson, Lennart; Sennemark, Eva

    2011-01-01

    Purpose: This article describes an innovative practice called Blended Learning Networks (BLNs) whose aim is to enable older people, their families, and care providers to exchange knowledge, learn together, and support each other in local development work so that care is improved for older people. BLNs were established in 31 municipalities, headed…

  12. Informal Social Networks of People with Profound Intellectual and Multiple Disabilities: Relationship with Age, Communicative Abilities and Current Living Arrangements

    ERIC Educational Resources Information Center

    Kamstra, A.; van der Putten, A. A. J.; Post, W. J.; Vlaskamp, C.

    2015-01-01

    Background: People with profound intellectual and multiple disabilities (PIMD) have limited informal social contacts. Research to determine the factors which can positively influence establishing sound informal social contacts is required. Materials and Methods: Regression analysis for 200 people with PIMD was used to analyse how age,…

  13. 956 IEEE COMMUNICATIONS LETTERS, VOL. 13, NO. 12, DECEMBER 2009 Secure Network Coding with

    E-print Network

    Liu, Huaping

    956 IEEE COMMUNICATIONS LETTERS, VOL. 13, NO. 12, DECEMBER 2009 Secure Network Coding with Minimum to achieve complete security in networks with network coding, it has been shown that at least original is minimized. Index Terms--Network coding, complete security, hash func- tion, information rate. I

  14. Building a Shared Information Network.

    ERIC Educational Resources Information Center

    Stanat, Ruth

    1991-01-01

    Discussion of information needs in a business environment focuses on how to build a shared information network. Highlights include the evolution of corporate intelligence systems; results of a survey that examined the information networking needs of large corporations; and a case study of the development of an information network at Citibank N.A.…

  15. Information Communication Highways in the 1990s: An Analysis of Their Potential Impact on Library Automation.

    ERIC Educational Resources Information Center

    Kibirige, Harry M.

    1991-01-01

    Discussion of the potential effects of fiber optic-based communication technology on information networks and systems design highlights library automation. Topics discussed include computers and telecommunications systems, the importance of information in national economies, microcomputers, local area networks (LANs), national computer networks,…

  16. An innovative communication model to disseminate information.

    PubMed

    Crawford, Cecelia L; Johnson, Joyce A; Valdez, Regina M

    2011-01-01

    Nurse leaders need effective communication models to articulate the functions, processes, and activities of health care organizations. This article describes the development and use of a communication model to streamline the dissemination of information to the targeted organizational entities that need it. The model's step-by-step process enhances the broadcasting of information needed to ensure patient safety and promote quality patient care by capturing the components integral to the communication process. PMID:21135708

  17. MEASUREMENTBASED USAGE CHARGES IN COMMUNICATIONS NETWORKS

    E-print Network

    to exercise control. The congestion that has plagued the Internet because it lacks any mechanism for charging and pricing highlights the fact that without charges it is difficult to control congestion or divide networkMEASUREMENT­BASED USAGE CHARGES IN COMMUNICATIONS NETWORKS COSTAS COURCOUBETIS ICS

  18. Iowa Communications Network Enhancing Education in Iowa.

    ERIC Educational Resources Information Center

    Ivanovic, Greta

    1995-01-01

    Describes the Iowa Communications Network, a statewide fiber optic network capable of transporting interactive, two-way audio, video, voice, and data signals. Topics include statewide cooperation among educational and state organizations; classroom design, including interactive classrooms; access to the Internet; and use by noneducational…

  19. Multilevel secure mixed-media communication networks

    Microsoft Academic Search

    Raymond Cole; Donald Kallgren; Richard Hale; John R. Davis

    1989-01-01

    A communication system architecture that provides security for different groups of users while allowing each group access to a common pool of network and transmission assets is presented. Transmission assets can be mixed, operating with different propagation media and network protocols. Placement of encryption processes required to support security services is of particular interest. Support of secure relaying services within

  20. Stress Testing of Data-Communication Networks

    NASA Technical Reports Server (NTRS)

    Leucht, Kurt; Bedette, Guy

    2006-01-01

    NetStress is a computer program that stress-tests a data-communication network and components thereof. NetStress comprises two components running, respectively, in a transmitting system and a receiving system connected to a network under test

  1. Handoff criteria for personal communication networks

    Microsoft Academic Search

    V. Kapoor; G. Edwards; R. Sankar

    1994-01-01

    The rapid growth in wireless personal communication networks (PCN) has placed demands on higher system capacity and performance. One way to increase the capacity of a cellular system is by reducing the size of the cells to microcells. But, in such microcellular environment the frequency of handoff also increases. Since the handoffs increase the load on the network system, they

  2. Information fusion in wireless sensor networks

    Microsoft Academic Search

    Eduardo Freire Nakamura; Antonio Alfredo Ferreira Loureiro

    2008-01-01

    In wireless sensor networks (WSNs), energy consumption and data quality are two important issues due to limited energy resources and the need for accurate data. In this scenario, information fusion techniques (also reffered to as data fusion or data aggregation) have been used to distributedly process sensor data to save energy - by reducing the overall communication load - and

  3. Information Systems and Business Communication.

    ERIC Educational Resources Information Center

    Beswick, Raymond W., Ed.; Williams, Alfred B., Ed.

    Intended to provide orientation about the integration of business communication, business systems, and the researching and teaching of business communication, this books offers articles on a variety of topics concerning business communication. Titles of the articles and their authors are as follows: (1) "Office Technology: Voice Store-and-Forward"…

  4. Contemporary data communications and local networking principles

    NASA Astrophysics Data System (ADS)

    Chartrand, G. A.

    1982-08-01

    The most important issue of data communications today is networking which can be roughly divided into two catagories: local networking; and distributed processing. The most sought after aspect of local networking is office automation. Office automation really is the grand unification of all local communications and not of a new type of business office as the name might imply. This unification is the ability to have voice, data, and video carried by the same medium and managed by the same network resources. There are many different ways this unification can be done, and many manufacturers are designing systems to accomplish the task. Distributed processing attempts to share resources between computer systems and peripheral subsystems from the same or different manufacturers. There are several companies that are trying to solve both networking problems with the same network architecture.

  5. Environmental monitoring by wireless communication networks.

    PubMed

    Messer, Hagit; Zinevich, Artem; Alpert, Pinhas

    2006-05-01

    The global spread of wireless networks brings a great opportunity for their use in environmental studies. Weather, atmospheric conditions, and constituents cause propagation impairments on radio links. As such, while providing communication facilities, existing wireless communication systems can be used as a widely distributed, high-resolution atmospheric observation network, operating in real time with minimum supervision and without additional cost. Here we demonstrate how measurements of the received signal level, which are made in a cellular network, provide reliable measurements for surface rainfall. We compare the estimated rainfall intensity with radar and rain gauge measurements. PMID:16675693

  6. Scalable Optical-Fiber Communication Networks

    NASA Technical Reports Server (NTRS)

    Chow, Edward T.; Peterson, John C.

    1993-01-01

    Scalable arbitrary fiber extension network (SAFEnet) is conceptual fiber-optic communication network passing digital signals among variety of computers and input/output devices at rates from 200 Mb/s to more than 100 Gb/s. Intended for use with very-high-speed computers and other data-processing and communication systems in which message-passing delays must be kept short. Inherent flexibility makes it possible to match performance of network to computers by optimizing configuration of interconnections. In addition, interconnections made redundant to provide tolerance to faults.

  7. Networking issues in medical implant communications

    Microsoft Academic Search

    Bin Zhen; Huan-Bang Li; Ryuji Kohno

    2009-01-01

    IEEE 802.15 working group established a new task group, body area network (TG-BAN), to develop short range wireless technology in and around human body recently. This paper investigates networking issues in implant communications at 2.4 GHz frequency band. The object is better understanding of medical implant networks and how and where to start TG- BAN work. We applied IEEE 802.15.4b

  8. Challenges of Integrating NASAs Space Communication Networks

    NASA Technical Reports Server (NTRS)

    Reinert, Jessica M.; Barnes, Patrick

    2013-01-01

    The transition to new technology, innovative ideas, and resistance to change is something that every industry experiences. Recent examples of this shift are changing to using robots in the assembly line construction of automobiles or the increasing use of robotics for medical procedures. Most often this is done with cost-reduction in mind, though ease of use for the customer is also a driver. All industries experience the push to increase efficiency of their systems; National Aeronautics and Space Administration (NASA) and the commercial space industry are no different. NASA space communication services are provided by three separately designed, developed, maintained, and operated communications networks known as the Deep Space Network (DSN), Near Earth Network (NEN) and Space Network (SN). The Space Communications and Navigation (SCaN) Program is pursuing integration of these networks and has performed a variety of architecture trade studies to determine what integration options would be the most effective in achieving a unified user mission support organization, and increase the use of common operational equipment and processes. The integration of multiple, legacy organizations and existing systems has challenges ranging from technical to cultural. The existing networks are the progeny of the very first communication and tracking capabilities implemented by NASA and the Jet Propulsion Laboratory (JPL) more than 50 years ago and have been customized to the needs of their respective user mission base. The technical challenges to integrating the networks are many, though not impossible to overcome. The three distinct networks provide the same types of services, with customizable data rates, bandwidth, frequencies, and so forth. The differences across the networks have occurred in effort to satisfy their user missions' needs. Each new requirement has made the networks more unique and harder to integrate. The cultural challenges, however, have proven to be a significant obstacle for integration. Over the past few decades of use, user missions and network personnel alike have grown accustomed to the processes by which services are provided by the NASA communications and navigation networks. The culture established by each network has created several challenges that need to be overcome in order to effectively integrate the networks. As with any change, there has been resistance, an apprehension to explore automation of existing processes, and a working environment that attempts to indirectly influence change without mandating compliance. Overcoming technical and cultural challenges is essential to successfully integrating the networks and although the challenges are numerous, the integration of the networks promises a more efficient space communications network for NASA and its customers, as well as potential long-term cost savings to the agency. This paper, Challenges of Integrating NASA Legacy Communications Networks, will provide a brief overview of the current NASA space communications networks as well as the an overview of the process implemented while performing the SCaN Trade Studies and an introduction to the requirements driving integration of the SCaN Networks. This paper will describe in detail the challenges experienced, both technical and cultural, while working with NASA space communications network-specific personnel. The paper will also cover lessons learned during the performance of architecture trade studies and provide recommendations for ways to improve the process.

  9. WATERSHED INFORMATION NETWORK

    EPA Science Inventory

    Resource Purpose: The Watershed Information Network is a set of about 30 web pages that are organized by topic. These pages access existing databases like the American Heritage Rivers Services database and Surf Your Watershed. WIN in itself has no data or data sets. L...

  10. MODELING INFORMATION DEPENDENCIES IN CONSTRUCTION PROJECT NETWORK ORGANIZATIONS

    Microsoft Academic Search

    Mehmet Koray Pekericli; Burcu Akinci; Itir Karaesmen

    This ongoing study intends to explore and formalize the information dependency patterns in network forms of organizations in construction project management. In construction projects, information is critical for seamless and cost-effective operations. Communication of project information and coordination of information exchanges between different project participants are essential for a project's success. On the other hand, a better understanding of information

  11. Efficient Communication Infrastructures for Distributed Control and Decision Making in Networked Stochastic Systems

    E-print Network

    Baras, John S.

    of communication and collaboration graphs in a networked system in the context of a coordination control, a communication graph, and an action (collaboration) graph. The first two graphs describe the information exchange Stochastic Systems John S. Baras and Pedram Hovareshti Abstract-- In networked systems, groups of agents

  12. Social Networking and Smart Technology: Viable Environmental Communication Tools…?

    NASA Astrophysics Data System (ADS)

    Montain, J.; Byrne, J. M.

    2010-12-01

    To what extent do popular social networking channels represent a viable means for disseminating information regarding environmental change to the general public? Are new forms of communication such as YouTube™, Facebook™, MySpace™ and Twitter™ and smart devices such as iPhone™ and BlackBerry™ useful and effective in terms motivating people into social action and behavioural modification; or do they simply pay ‘lip service’ to these pressing environmental issues? This project will explore the background connections between social networking and environmental communication and education; and outline why such tools might be an appropriate way to connect to a broad audience in an efficient and unconventional manner. Further, research will survey the current prevalence of reliable environmental change information on social networking Internet-based media; and finally, suggestions for improved strategies and new directions will be provided.

  13. Information communication scheme for loosely coupled mobile users in wireless sensor fields with multiple sources

    Microsoft Academic Search

    Euisin Lee; Fucai Yu; Min-Sook Jin; Sang-Ha Kim

    2009-01-01

    In wireless sensor networks, groups of mobile users interested in equivalent information could be classified into two categories according to existence of direct communication channel among the users: 1) loosely coupled user group and 2) tightly coupled user group. The loosely coupled group means that a mobile user should communicate with others via a wireless sensor network for querying, gathering,

  14. Universities Water Information Network

    NSDL National Science Digital Library

    The Universities Water Information Network (UWIN), located at Southern Illinois University in Carbondale, Illinois, "disseminates information of interest to the water resources community and all concerned with our water resources." Although much of the site is accessed by paid subscription only, several resources are offered free to anyone. A database of water related consulting firms contains contact information, including name, acronym, postal address, phone, fax, email, and contact person. Another helpful resource, the organizations database, lists water resource agencies, organizations, and institutions in the US, Caribbean, and Central America. Other items of interest include job listings, press releases, and more.

  15. Interactive Weather Information Network

    NSDL National Science Digital Library

    Offered by the National Oceanic and Atmospheric Administration (NOAA), the Interactive Weather Information Network (IWIN) is a collection of interactive weather maps and satellite images that is updated every five seconds. Visitors can see cloud cover animation loops, NEXRAD Radar images of precipitation, a map of all current weather fronts, and an interactive national map to see information about any particular state. Other information on the site includes a listing of any active weather warnings, a link for world weather data, and more, making this a must-see site for all those users interested in the most current weather happenings anywhere.

  16. Designing Satellite Communication Networks by Zero-One Quadratic Programming

    E-print Network

    Helme, Marcia P.

    In satellite communications networks, distinctive facilities called homing stations perform special transmission functions. Local demand nodes clustered around each homing station communicate with each other via a local ...

  17. Gordon's Information and Communications Technologies (ICT) Blog

    NSDL National Science Digital Library

    Snyder, Gordon F.

    This page presents the blog of Gordon F. Snyder of the National Center for Information and Communications Technologies, presenting perspectives on the Information and Communications Technology (ICT) Industries and Education. Gordon blogs about topics ranging from personal interests, technology and politics, the birth and death of new technologies, and industry developments. In addition to the blog's archives, visitors can find Snyder's photo stream, links to other bloggers of interest, and more information about Gordon himself.

  18. Understanding learning: Applications to Information and Communication Technology (ICT)

    E-print Network

    Paris-Sud XI, Université de

    Understanding learning: Applications to Information and Communication Technology (ICT to Information and Communication Technology (ICT) and to Environmental Governance & Learning Pathways ................................................................................................................................................... 3 PART I : UNDERSTANDING LEARNING: APPLICATIONS TO INFORMATION AND COMMUNICATION TECHNOLOGY (ICT

  19. 31 CFR 542.306 - Information and communications technology.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...2014-07-01 false Information and communications technology. 542.306 Section...Definitions § 542.306 Information and communications technology. The term information and communications technology means any...

  20. Near Field Communication Network Services

    Microsoft Academic Search

    Jorma Ylinen; Mikko Koskela; Lari Iso-anttila; Pekka Loula

    2009-01-01

    Near Field Communication (NFC) provides means to close-range contactless identification and communication for mobile phones and other devices alike. NFC is a new technology but it is maturing fast as it is being standardized. The first NFC services have mostly been simple applications but with the expansion of NFC technology and its application areas there is an urgent need to

  1. Autonomous Power Supplied Wireless Mesh Network for Disaster Information System

    Microsoft Academic Search

    Toshihiro Suzuki; Yoshitaka Shibata

    2010-01-01

    It is proved that wireless network is suitable for disaster information infrastructure because of its robustness, mobility and flexibility. However current conventional wireless networks have limit in communication distance because of low electro-magnetic power density, non-directional antenna. This is quite fatal as emergency network particularly in mountain areas like Japan. In order to solve those problems, in this paper, we

  2. The NASA Space Communications Data Networking Architecture

    NASA Technical Reports Server (NTRS)

    Israel, David J.; Hooke, Adrian J.; Freeman, Kenneth; Rush, John J.

    2006-01-01

    The NASA Space Communications Architecture Working Group (SCAWG) has recently been developing an integrated agency-wide space communications architecture in order to provide the necessary communication and navigation capabilities to support NASA's new Exploration and Science Programs. A critical element of the space communications architecture is the end-to-end Data Networking Architecture, which must provide a wide range of services required for missions ranging from planetary rovers to human spaceflight, and from sub-orbital space to deep space. Requirements for a higher degree of user autonomy and interoperability between a variety of elements must be accommodated within an architecture that necessarily features minimum operational complexity. The architecture must also be scalable and evolvable to meet mission needs for the next 25 years. This paper will describe the recommended NASA Data Networking Architecture, present some of the rationale for the recommendations, and will illustrate an application of the architecture to example NASA missions.

  3. Automated troubleshooting of a mobile communication network using Bayesian networks

    Microsoft Academic Search

    R. Barco; L. Nielsen; R. Guerrero; G. Hylander; S. Patel

    2002-01-01

    Operators of mobile communication networks face the challenging task of maintaining a complex network with thousands of cells. It requires highly skilled troubleshooting engineers to avoid a situation where subscribers are not properly served. This paper presents a new method for automating the troubleshooting task, thereby freeing a large portion of resources for other purposes. The method is described in

  4. Global Communications Network 2.9.1

    NSDL National Science Digital Library

    More and more individuals are turning to the Internet to communicate with colleagues, friends, and relatives and there are a number of helpful programs currently available for general use. This edition of the Global Communications Network application allows visitors to engage in video and voice chat and administer their own chat rooms, all within a secure format. This version is compatible with Windows 95 or newer.

  5. Anonymous communications in mobile ad hoc networks

    Microsoft Academic Search

    Yanchao Zhang; Wei Liu; Wenjing Lout

    2005-01-01

    Abstract—Due to the broadcast nature of radio transmissions, communications in mobile ad hoc networks (MANETs) are more susceptible to malicious traffi ca nalysis. In this paper we propose a novel anonymous on-demand routing protocol, termed MASK, to enable anonymous,communications thereby thwarting possible traffic analysis attacks. Based on a new cryptographic concept called pairing, we first propose an anonymous neighborhood authentication

  6. The Deep Space Network. [tracking and communication functions and facilities

    NASA Technical Reports Server (NTRS)

    1974-01-01

    The objectives, functions, and organization of the Deep Space Network are summarized. The Deep Space Instrumentation Facility, the Ground Communications Facility, and the Network Control System are described.

  7. Communicating health information to disadvantaged populations.

    PubMed

    Beacom, Amanda M; Newman, Sandra J

    2010-01-01

    Interest in the communication of health information among disadvantaged populations has increased in recent years with the shift from a model of patient-provider communication to one of a more empowered healthcare consumer; with the use of new communication technologies that increase the number of channels through which health information may be accessed; and with the steadily increasing number of people without health insurance. Three separate research literatures contribute to our current understanding of this issue. In the medicine and public health literature, disparities in health access and outcomes among socioeconomic, ethnic, and racial groups are now well documented. In the information sciences literature, scholars note that on a continuum of health information behaviors, ranging from information avoidance and nonseeking to active seeking, nonseeking behaviors are associated with disadvantaged populations. In the communication literature, enthusiasm over the technology-driven growth of online health information seeking is tempered by evidence supporting the knowledge gap hypothesis, which indicates that as potential access to health information increases, systematic gaps in health knowledge also increase as groups with higher socioeconomic status acquire this information at a faster rate than those with lower socioeconomic status. A number of diverse strategies show promise in reducing information and health disparities, including those that focus on technology, such as programs to increase computer and Internet access, skills, and comprehension; those that focus on interpersonal communication, such as the community health worker model; and those that focus on mass media channels, such as entertainment education. PMID:20216358

  8. Information and Communication in Lean Product Development

    E-print Network

    Graebsch, Martin

    In this thesis, the implications and influences that information and communication impose on lean product development in general, as well as the development of a lean Product Development Value Stream Display (lean PDVSD) ...

  9. INTERNATIONAL JOURNAL OF SATELLITE COMMUNICATIONS AND NETWORKING Int. J. Satell. Commun. Network. 2006; 24:261281

    E-print Network

    INTERNATIONAL JOURNAL OF SATELLITE COMMUNICATIONS AND NETWORKING Int. J. Satell. Commun. Network: 10.1002/sat.841 Turbo-coded APSK modulations design for satellite broadband communications Riccardo phase shift keying (APSK) modulation with application to satellite broadband communications. APSK

  10. Experimental performance evaluation of software defined networking (SDN) based data communication networks for large scale flexi-grid optical networks.

    PubMed

    Zhao, Yongli; He, Ruiying; Chen, Haoran; Zhang, Jie; Ji, Yuefeng; Zheng, Haomian; Lin, Yi; Wang, Xinbo

    2014-04-21

    Software defined networking (SDN) has become the focus in the current information and communication technology area because of its flexibility and programmability. It has been introduced into various network scenarios, such as datacenter networks, carrier networks, and wireless networks. Optical transport network is also regarded as an important application scenario for SDN, which is adopted as the enabling technology of data communication networks (DCN) instead of general multi-protocol label switching (GMPLS). However, the practical performance of SDN based DCN for large scale optical networks, which is very important for the technology selection in the future optical network deployment, has not been evaluated up to now. In this paper we have built a large scale flexi-grid optical network testbed with 1000 virtual optical transport nodes to evaluate the performance of SDN based DCN, including network scalability, DCN bandwidth limitation, and restoration time. A series of network performance parameters including blocking probability, bandwidth utilization, average lightpath provisioning time, and failure restoration time have been demonstrated under various network environments, such as with different traffic loads and different DCN bandwidths. The demonstration in this work can be taken as a proof for the future network deployment. PMID:24787842

  11. Lewis Information Network (LINK): Background and overview

    NASA Technical Reports Server (NTRS)

    Schulte, Roger R.

    1987-01-01

    The NASA Lewis Research Center supports many research facilities with many isolated buildings, including wind tunnels, test cells, and research laboratories. These facilities are all located on a 350 acre campus adjacent to the Cleveland Hopkins Airport. The function of NASA-Lewis is to do basic and applied research in all areas of aeronautics, fluid mechanics, materials and structures, space propulsion, and energy systems. These functions require a great variety of remote high speed, high volume data communications for computing and interactive graphic capabilities. In addition, new requirements for local distribution of intercenter video teleconferencing and data communications via satellite have developed. To address these and future communications requirements for the next 15 yrs, a project team was organized to design and implement a new high speed communication system that would handle both data and video information in a common lab-wide Local Area Network. The project team selected cable television broadband coaxial cable technology as the communications medium and first installation of in-ground cable began in the summer of 1980. The Lewis Information Network (LINK) became operational in August 1982 and has become the backbone of all data communications and video.

  12. Wireless Extensions of Wired Industrial Communications Networks

    Microsoft Academic Search

    Gianluca Cena; Adriano Valenzano; Stefano Vitturi

    2007-01-01

    Wireless (sub)networks are becoming appealing for their characteristics also for the industrial automation and manufacturing scenarios. Since they cannot be considered as a total replacement for more traditional wired communications, at least in the short\\/mid-term, it is worth focusing on their integration with popular industrial wired solutions in order to achieve efficiency and performance for the overall networked system. This

  13. Global Scheme of Lunar-Earth Information Network LI Teng, XU Min and YANG Wei

    E-print Network

    Li, Teng

    , through which an information collection and communication network is formed. Moreover, the triune-Earth Information Network is composed of a lunar-earth Messenger, a lunar Orbiter and a Lunar Probe net on the moon and communication network is formed. 2.2 Contents 1. Moonscape Lunar Probe Net: The lunar probe net may

  14. Ubiquitous Interpersonal Communication Ad-Hoc Networks and the Internet

    E-print Network

    Biagioni, Edoardo S.

    ), and over ad-hoc and delay-tolerant networks composed of the mobile devices themselves. This network-limited broadcast and Delay Tolerant Networking (DTN) within the ad-hoc network. Each device has a policy Infrastructureless Communication, Interpersonal Com- munication, Ad-Hoc Network, Delay-Tolerant Network, Networking

  15. Hybrid Mobile Communication Networks for Planetary Exploration

    NASA Technical Reports Server (NTRS)

    Alena, Richard; Lee, Charles; Walker, Edward; Osenfort, John; Stone, Thom

    2007-01-01

    A paper discusses the continuing work of the Mobile Exploration System Project, which has been performing studies toward the design of hybrid communication networks for future exploratory missions to remote planets. A typical network could include stationary radio transceivers on a remote planet, mobile radio transceivers carried by humans and robots on the planet, terrestrial units connected via the Internet to an interplanetary communication system, and radio relay transceivers aboard spacecraft in orbit about the planet. Prior studies have included tests on prototypes of these networks deployed in Arctic and desert regions chosen to approximate environmental conditions on Mars. Starting from the findings of the prior studies, the paper discusses methods of analysis, design, and testing of the hybrid communication networks. It identifies key radio-frequency (RF) and network engineering issues. Notable among these issues is the study of wireless LAN throughput loss due to repeater use, RF signal strength, and network latency variations. Another major issue is that of using RF-link analysis to ensure adequate link margin in the face of statistical variations in signal strengths.

  16. An ideal model of informed consent communication.

    PubMed

    Jeoung, Yeon Ok; Yang, Tae Ki; Bak, Yong Ik; Lim, In Seok; Sim, Ki-Bum

    2014-03-01

    Informed consent (IC) should be a form of communication between a physician and patient in which information regarding all options of a medical procedure and the patient's preference is shared. The aim of this study was to create a standard for communication by IC for physicians. The IC standard was developed based on an analysis of a dialogue in our previous experience with a medical communication program and a review of the literature. The dialogue pattern of the IC standard had the following six elements: opening; orientation; disclosure of information; conforming and complementing; shared decision making; and closing. Factors that influenced effective IC-based communication included preparation, attitude, empathy, listening, a psychosocial factor, nonverbal communication, explanation, and understanding. The IC communication standard will be useful in improving the quality of communication between a physician and patient in obtaining IC. It will also be used as a guideline for communication educators and medical students. Innovative strategies and rigorous studies are needed to improve IC counseling to establish effective patient-centered interviews. PMID:25805075

  17. CollegeofCommunicationandInformation CJT Communication, Journalism, Telecommunications

    E-print Network

    MacAdam, Keith

    in communication or consent of instructor. CJT 631 PROSEMINAR IN INTERPERSONAL COMMUNICATION. (3CollegeofCommunicationandInformation CJT Communication, Journalism, Telecommunications (Graduate Bulletin 1 CJT 601 PROSEMINAR IN COMMUNICATION. (3) Introduction to graduate study; theory and systems

  18. Multimedia Communications over IP Networks 4 -6 September 2000

    E-print Network

    Abu-Rgheff, Mosa Ali

    Multimedia Communications over IP Networks 4 - 6 September 2000 Evolution of the Internet David@plymouth.ac.uk School of Computing #12;Multimedia Communications over IP Networks 4 - 6 September 2000 Evolution' applying at each level: #12;Multimedia Communications over IP Networks 4 - 6 September 2000 Evolution

  19. ANALYSIS OF HANDOVER CHARACTERISTICS IN SHADOWED LEO SATELLITE COMMUNICATION NETWORKS

    E-print Network

    Sung, Dan Keun

    ANALYSIS OF HANDOVER CHARACTERISTICS IN SHADOWED LEO SATELLITE COMMUNICATION NETWORKS£ YOUNG HOON In the near future low earth orbit (LEO) satellite communication networks will partially substitute for fixed communication networks more than one satellite need to be simultaneously visible in order to hand over a call

  20. A study on industrial communication networking: Ethernet based implementation

    Microsoft Academic Search

    Hairulazwan Hashim; Zainal Alam Haron

    2007-01-01

    Recent enhancement of the industrial communications and networking are possible to apply in Ethernet networks system at all levels of industrial automation, especially in the controller level whereby the data exchanges in real-time communication is mandatory. This paper is about a study on the development of industrial communications network based on the Ethernet protocol and thus implement it into computer

  1. Southwest Environmental Information Network

    NSDL National Science Digital Library

    The Southwest Environmental Information Network (SEINet) is a series of linked databases and accompanying web software helpful in using those databases, which will be of interest to the environmental research community in Arizona, the Southwest, and elsewhere. SEINet allows users to locate, access, and work with a variety of data, including biological collections, ecological research data, GIS data, taxonomic information, bibliographies, and research protocols. Searchable databases include herbaria; pollen, fruit and seed collections; and mammal, bird, reptile, and amphibian collections. There is also a library of plant and lichen images; links to identification keys and species checklists from various research projects; information on NaviKey (a Java applet and application for accessing descriptive data); and Symbiota web tools (which integrate biological community knowledge and data in order to help identify plants).

  2. Communication Algorithms for Wireless Ad Hoc Networks 

    E-print Network

    Viqar, Saira

    2012-10-19

    . We present two different algorithms that implement this layer with varying progress guarantees. In the second part of this dissertation we give an algorithm which allows nodes in a mobile wireless ad hoc network to communicate reliably and at the same...

  3. Teletraffic Model for Indoor Wireless Communication Network

    Microsoft Academic Search

    Omar Y. K. Alani; Jaafar M. H Elmirghani

    2009-01-01

    Airports are now amongst the most complex built environments known. Millions of people are using airports every year. However, providing adequate and reliable communication facilities to passengers and to other airport services represents a challenging issue. The Intelligent Airport (TINA) project aims to develop a new seamless wireless\\/wired ubiquitous infrastructure able to provide seamless integration at the service, network and

  4. Protocol for Communication Networking for Formation Flying

    NASA Technical Reports Server (NTRS)

    Jennings, Esther; Okino, Clayton; Gao, Jay; Clare, Loren

    2009-01-01

    An application-layer protocol and a network architecture have been proposed for data communications among multiple autonomous spacecraft that are required to fly in a precise formation in order to perform scientific observations. The protocol could also be applied to other autonomous vehicles operating in formation, including robotic aircraft, robotic land vehicles, and robotic underwater vehicles. A group of spacecraft or other vehicles to which the protocol applies could be characterized as a precision-formation- flying (PFF) network, and each vehicle could be characterized as a node in the PFF network. In order to support precise formation flying, it would be necessary to establish a corresponding communication network, through which the vehicles could exchange position and orientation data and formation-control commands. The communication network must enable communication during early phases of a mission, when little positional knowledge is available. Particularly during early mission phases, the distances among vehicles may be so large that communication could be achieved only by relaying across multiple links. The large distances and need for omnidirectional coverage would limit communication links to operation at low bandwidth during these mission phases. Once the vehicles were in formation and distances were shorter, the communication network would be required to provide high-bandwidth, low-jitter service to support tight formation-control loops. The proposed protocol and architecture, intended to satisfy the aforementioned and other requirements, are based on a standard layered-reference-model concept. The proposed application protocol would be used in conjunction with conventional network, data-link, and physical-layer protocols. The proposed protocol includes the ubiquitous Institute of Electrical and Electronics Engineers (IEEE) 802.11 medium access control (MAC) protocol to be used in the datalink layer. In addition to its widespread and proven use in diverse local-area networks, this protocol offers both (1) a random- access mode needed for the early PFF deployment phase and (2) a time-bounded-services mode needed during PFF-maintenance operations. Switching between these two modes could be controlled by upper-layer entities using standard link-management mechanisms. Because the early deployment phase of a PFF mission can be expected to involve multihop relaying to achieve network connectivity (see figure), the proposed protocol includes the open shortest path first (OSPF) network protocol that is commonly used in the Internet. Each spacecraft in a PFF network would be in one of seven distinct states as the mission evolved from initial deployment, through coarse formation, and into precise formation. Reconfiguration of the formation to perform different scientific observations would also cause state changes among the network nodes. The application protocol provides for recognition and tracking of the seven states for each node and for protocol changes under specified conditions to adapt the network and satisfy communication requirements associated with the current PFF mission phase. Except during early deployment, when peer-to-peer random access discovery methods would be used, the application protocol provides for operation in a centralized manner.

  5. ELEC6014 (EZ412/612) Radio Communications Networks and Systems S Chen ELEC6014 Radio Communications Networks and Systems

    E-print Network

    Chen, Sheng

    , Fundamentals of Wireless Communication. Cambridge University Press, 2005. 1 #12;ELEC6014 (EZ412/612) Radio;ELEC6014 (EZ412/612) Radio Communications Networks and Systems S Chen Channel Fundamentals · IdealELEC6014 (EZ412/612) Radio Communications Networks and Systems S Chen ELEC6014 Radio Communications

  6. On cost-effective communication network designing

    E-print Network

    Zhang, Guoqiang

    2009-01-01

    How to efficiently design a communication network is a paramount task for network designing and engineering. It is, however, not a single objective optimization process as perceived by most previous researches, i.e., to maximize its transmission capacity, but a multi-objective optimization process, with lowering its cost to be another important objective. These two objectives are contradictive in that optimizing one will inevitably deteriorate the other. After a deep investigation of the impact that network topology, node capability scheme and routing algorithm as well as their interplays have on the two objectives, this Letter presents a systematic approach to achieving a cost-effective design by carefully choosing the three designing aspects. Only when routing algorithm and node capability scheme are elaborately chosen can BA-like scale-free networks have the potential of achieving good tradeoff between the two objectives. Random networks, on the other hand, have the built-in character for a cost-effect des...

  7. Traffic Theory Approach for Heterogeneous Mobile Communication Networks

    Microsoft Academic Search

    Stephan Goebbels

    2007-01-01

    This paper presents a new traffic theory based approach for the analysis of heterogeneous wireless communication networks. While traffic theory is widely spread for the analysis of wired networks like the Internet the adaptation of these methods for wireless and especially heterogeneous networks is not yet accomplished. New upcoming mobile communication networks will be ruled by continuously switching radio access

  8. Radio Networks With Reliable Communication Yvo Desmedt1

    E-print Network

    Wang, Yongge

    is a local area network like an Ethernet bus or a token ring. Another example is the Bluetooth or IEEE 802.11 network. We consider a radio network in which stations can communicate with each other using frequenciesRadio Networks With Reliable Communication Yvo Desmedt1 , Yongge Wang2 , Rei Safavi-Naini3

  9. Training artificial neural networks using variable precision incremental communication

    Microsoft Academic Search

    Ali A. Ghorbani; Virendra C. Bhavsar

    1994-01-01

    We have earlier proposed incremental inter-node communication to reduce the communication cost as well as time of the learning process in artificial neural networks. In the incremental communication, instead of communicating the full magnitude of an input (output) variable of a neuron, only the increment\\/decrement to the previous value of the variable, using reduced precision, is sent on a communication

  10. 76 FR 23812 - Reliability and Continuity of Communications Networks, Including Broadband Technologies; Effects...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-28

    ...FEDERAL COMMUNICATIONS COMMISSION [PS Docket Nos...Reliability and Continuity of Communications Networks, Including Broadband...Technologies; Effects on Broadband Communications Networks of Damage or...

  11. 78 FR 69018 - Improving the Resiliency of Mobile Wireless Communications Networks; Reliability and Continuity...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-18

    ...FEDERAL COMMUNICATIONS COMMISSION 47 CFR Part 4 [PS Docket...the Resiliency of Mobile Wireless Communications Networks; Reliability and Continuity of Communications Networks, Including Broadband...

  12. Cooperative communication in wireless networks

    Microsoft Academic Search

    Aria Nosratinia; Todd E. Hunter; A. Hedayat

    2004-01-01

    Transmit diversity generally requires more than one antenna at the transmitter. However, many wireless devices are limited by size or hardware complexity to one antenna. Recently, a new class of methods called cooperative communication has been proposed that enables single-antenna mobiles in a multi-user environment to share their antennas and generate a virtual multiple-antenna transmitter that allows them to achieve

  13. Organizational Alternatives for a Pacific Educational Computer-Communications Network.

    ERIC Educational Resources Information Center

    Ah Mai, Karen L.

    Organizational alternatives for a Pacific educational computer-communications network are studied through the examples provided by other networks. A survey of networks is provided with a discussion of the history and development of networks and the distinctions in network technology and applications. Nine specific networks are described. Libraries…

  14. The International Coral Reef Information Network

    NSDL National Science Digital Library

    International Coral Reef Action Network (ICRAN)

    This extensive site was originally created to support coral reef conservation by the International Coral Reef Initiative (ICRI). The site serves to provide general coral reef information, tools and resources, and a central coral reef communications and network hub. The site also provides a library which houses descriptions of brochures, books, videos and other items suitable for coral reef awareness and education efforts. Some publications are available for download directly from this site, while others are available for purchase.

  15. WindTalker: A P2P-Based Low-Latency Anonymous Communication Network

    NASA Astrophysics Data System (ADS)

    Zhang, Jia; Duan, Haixin; Liu, Wu; Wu, Jianping

    Compared with traditional static anonymous communication networks, the P2P architecture can provide higher anonymity in communication. However, the P2P architecture also leads to more challenges, such as route, stability, trust and so on. In this paper, we present WindTalker, a P2P-based low-latency anonymous communication network. It is a pure decentralized mix network and can provide low-latency services which help users hide their real identity in communication. In order to ensure stability and reliability, WindTalker imports “seed nodes” to help a peer join in the P2P network and the peer nodes can use gossip-based protocol to exchange active information. Moreover, WindTalker uses layer encryption to ensure the information of relayed messages cannot be leaked. In addition, malicious nodes in the network are the major threat to anonymity of P2P anonymous communication, so WindTalker imports a trust mechanism which can help the P2P network exclude malicious nodes and optimize the strategy of peer discovery, tunnel construction, and relaying etc. in anonymous communications. We deploy peer nodes of WindTalker in our campus network to test reliability and analyze anonymity in theory. The network measurement and simulation analysis shows that WindTalker can provide low-latency and reliable anonymous communication services.

  16. Network Design for Information Networks (Extended Abstract)

    E-print Network

    Swamy, Chaitanya

    information from) central nodes and/or each # Dept. of Computer Science, Upson Hall, Cornell University. For example, in a sensor network application, dis­ tributed sensors need to send information to central nodes, and information sent from sensors can often be aggregated well along the paths. Another setting is content

  17. Network Design for Information Networks (Extended Abstract)

    E-print Network

    Swamy, Chaitanya

    information from) central nodes and/or each Dept. of Computer Science, Upson Hall, Cornell University, Ithaca, in a sensor network application, dis- tributed sensors need to send information to central nodes, and information sent from sensors can often be aggregated well along the paths. Another setting is content

  18. Coherent Distributed Techniques for Tactical Radio Networks: Enabling Long Range Communications

    E-print Network

    Brown III, Donald R.

    Coherent Distributed Techniques for Tactical Radio Networks: Enabling Long Range Communications of tactical radios to enable extended-range communications. Conventional tactical communication systems-- Communication equipment; Radio communication; Wireless Networks; Distributed algorithms; Time measurement; MIMO

  19. EE624 INFORMATION AND CODING THEORY FOR WIRELESS COMMUNICATIONS

    E-print Network

    Jagannatham, Aditya K.

    EE624 INFORMATION AND CODING THEORY FOR WIRELESS COMMUNICATIONS Radical advances, advances in Information Theory have led to a fundamental understanding of data rates over current, modern information and coding theory forms the bedrock of broadband wireless communications

  20. Position estimation of transceivers in communication networks

    DOEpatents

    Kent, Claudia A. (Pleasanton, CA); Dowla, Farid (Castro Valley, CA)

    2008-06-03

    This invention provides a system and method using wireless communication interfaces coupled with statistical processing of time-of-flight data to locate by position estimation unknown wireless receivers. Such an invention can be applied in sensor network applications, such as environmental monitoring of water in the soil or chemicals in the air where the position of the network nodes is deemed critical. Moreover, the present invention can be arranged to operate in areas where a Global Positioning System (GPS) is not available, such as inside buildings, caves, and tunnels.

  1. (CICT) Computing, Information, and Communications Technology Overview

    NASA Technical Reports Server (NTRS)

    VanDalsem, William R.

    2003-01-01

    The goal of the Computing, Information, and Communications Technology (CICT) program is to enable NASA's Scientific Research, Space Exploration, and Aerospace Technology Missions with greater mission assurance, for less cost, with increased science return through the development and use of advanced computing, information and communications technologies. This viewgraph presentation includes diagrams of how the political guidance behind CICT is structured. The presentation profiles each part of the NASA Mission in detail, and relates the Mission to the activities of CICT. CICT's Integrated Capability Goal is illustrated, and hypothetical missions which could be enabled by CICT are profiled. CICT technology development is profiled.

  2. Featherlight Information Network with Delay-Endurable RFID Support (FINDERS)

    E-print Network

    Wu, Hongyi

    . It expands the use of RFID gear for wireless network construction, aiming to find events of interest, without power supply for long-lasting applications. It investigates into the use of RFID gear for wireless and gather aggregate information. FINDERS faces unprecedented challenges in communication and networking, due

  3. Communication Networks from the Enron Email Corpus \\

    Microsoft Academic Search

    Jana Diesner; Terrill L. Frantz; Kathleen M. Carley

    2005-01-01

    The Enron email corpus is appealing to researchers because it represents a rich temporal record of internal communication\\u000a within a large, real-world organization facing a severe and survival-threatening crisis. We describe how we enhanced the original\\u000a corpus database and present findings from our investigation undertaken with a social network analytic perspective. We explore\\u000a the dynamics of the structure and properties

  4. Reliable communication for DuST networks

    Microsoft Academic Search

    V. Rosset; Pedro Souto; Francisco Vasques

    2009-01-01

    We present a family of reliable broadcast protocols designed to take advantage of the dual scheduling TDMA (DuST) scheme provided by current state-of-the-art automotive control networks such as FlexRay. These protocols are a complement to FlexRay's native communication services, which do not provide sufficient fault tolerance for safety-critical applications. A reliability evaluation of the proposed protocols carried out with the

  5. Information security in networked supply chains: impact of network vulnerability and supply chain integration on incentives to invest

    Microsoft Academic Search

    Tridib Bandyopadhyay; Varghese Jacob; Srinivasan Raghunathan

    2010-01-01

    Recent supply chain reengineering efforts have focused on integrating firms’ production, inventory and replenishment activities\\u000a with the help of communication networks. While communication networks and supply chain integration facilitate optimization\\u000a of traditional supply chain functions, they also exacerbate the information security risk: communication networks propagate\\u000a security breaches from one firm to another, and supply chain integration causes breach on one

  6. Electronic Communication Networks for Education: Policy Implications for SEAs. Discussion Draft.

    ERIC Educational Resources Information Center

    Picus, Larry; Holznagel, Donald

    Providing the chief state school officers of the Northwest and the Pacific states with information on the policy options they face in establishing an electronic communication system, this paper is divided into four sections. The first section describes potential uses of electronic communication networks in education for correspondence, management…

  7. Promoting Communication Skills for Information Systems Students in Australian and Portuguese Higher Education: Action Research Study

    ERIC Educational Resources Information Center

    Isaias, Pedro; Issa, Tomayess

    2014-01-01

    This paper aims to examine the value of communication skills learning process through various assessments in Information Systems (IS) postgraduate units in Australia and Portugal. Currently, communication skills are indispensable to students in expanding their social networks and their knowledge at university and in the future workplace, since…

  8. Research on a Heat-supply Network Dispatching System Based on Geographical Information System (GIS)

    E-print Network

    Zhou, Z.; Zou, P.; Tang, H.; Fang, X.; Wang, W.

    2006-01-01

    -supply Network Dispatching System (HNDS). The system, based on Oracle database and Mapgis 6.5, compiles with Visual C++ software. With computer and communication techniques, the system dynamic inspects parameters and information of a heat-supply network, achieves...

  9. Social gating of sensory information during ongoing communication.

    PubMed

    Anders, Silke; Heussen, Yana; Sprenger, Andreas; Haynes, John-Dylan; Ethofer, Thomas

    2015-01-01

    Social context plays an important role in human communication. Depending on the nature of the source, the same communication signal might be processed in fundamentally different ways. However, the selective modulation (or "gating") of the flow of neural information during communication is not fully understood. Here, we use multivoxel pattern analysis (MVPA) and multivoxel connectivity analysis (MVCA), a novel technique that allows to analyse context-dependent changes of the strength interregional coupling between ensembles of voxels, to examine how the human brain differentially gates content-specific sensory information during ongoing perception of communication signals. In a simulated electronic communication experiment, participants received two alternative text messages during fMRI ("happy" or "sad") which they believed had been sent either by their real-life friend outside the scanner or by a computer. A region in the dorsal medial prefrontal cortex (dmPFC) selectively increased its functional coupling with sensory-content encoding regions in the visual cortex when a text message was perceived as being sent by the participant's friend, and decreased its functional coupling with these regions when a text message was perceived as being sent by the computer. Furthermore, the strength of neural encoding of content-specific information of text messages in the dmPFC was modulated by the social tie between the participant and her friend: the more of her spare time a participant reported to spend with her friend the stronger was the neural encoding. This suggests that the human brain selectively gates sensory information into the relevant network for processing the mental states of others, depending on the source of the communication signal. PMID:25315788

  10. Control of Multi-hop Communication Networks for Inter-session Network Coding

    E-print Network

    Eryilmaz, Atilla

    1 Control of Multi-hop Communication Networks for Inter-session Network Coding Atilla Eryilmaz and where to perform inter-session network coding for a general network model both under wired and wireless The efficient use of the scarce resources of communication networks is critical in providing high quality

  11. Ubiquitous Interpersonal Communication Ad-Hoc Networks and the Internet

    E-print Network

    Biagioni, Edoardo S.

    infrastructure networks (the Internet), and over ad-hoc and delay-tolerant networks composed of the mobile, and use ad-hoc and delay-tolerant networking to continue delivering packets when Internet access. The decentralized model of security builds a flexible trust network on top of the social network of communicating

  12. Determinants of Communication Network Involvement: Connectedness and Integration.

    ERIC Educational Resources Information Center

    Monge, Peter R.; And Others

    1983-01-01

    Developed structural equation models of involvement in communication networks in organizations for communication network connectedness and for network integration. A questionnaire was administered to members of a naval training facility (N=125). Models showed acceptable goodness-of-fit for the connectedness model and excellent goodness-of-fit for…

  13. A new survivability measure for military communication networks

    Microsoft Academic Search

    Haizhuang Kang; Clive Butler; Qingping Yang; Jiamo Chen

    1998-01-01

    A new measure for survivability of military communication networks based upon topological structures is presented. The proposed measure can be used to evaluate and enhance the survivability of military communication networks, which is illustrated through case studies. The computer simulation results have shown that the new measure can well reflect the survivability of networks. It can be used as a

  14. Child Rights Information Network

    NSDL National Science Digital Library

    Established in 1995 and based in London, the Children's Rights Information Network (CRIN) uses the United Nations Convention on the Rights of the Child (CRC) as their inspiration. Visitors unfamiliar with the reasons for the need for a group that advocates for the rights of children should check out the "Issues" tab. The CRIN Quiz section is a good place for visitors to learn about some of the specifics of children's rights in various countries, such as the "African Committee on the Rights and the Welfare of the Child" from 15/03/2010 and "Child Rights and the United States" from 05/11/2008. There are quizzes on some specific issues that involve children, such as "Child Slavery" from 28/03/2007 and "Quiz on Children Affected by Armed Conflict" from 24/11/2006. The "Information By Country", which can be accessed on the left hand side of the homepage, features International Law, National Law, and Regional Law related to the country, as well as the "Latest Resources", which include such valuable guides as the "Human Rights Watch: Global Report 2010".

  15. Global Raptor Information Network

    NSDL National Science Digital Library

    The Peregrine Fund

    The Global Raptor Information Network includes newly compiled species accounts for 331 species of diurnal raptors (hawks, eagles, falcons, vultures). These are linked to homepages of raptor researchers from 66 countries, and the site also offers a searchable bibliographic database (with nearly 39,000 records) on birds of prey. Other features include a species database, which includes distributional information and conservation status for raptors in 260 countries and island groups, links to raptor organizations, hawkwatches, database resources, and homepages of over 200 ornithological journals. There is also a bulletin board with notices of upcoming raptor meetings, recent raptor news, and appeals for assistance. The site is maintained by The Peregrine Fund in Boise, Idaho in an effort to create a global community of raptor researchers and to make its research library, which contains one of the largest collections of ornithological references (now about 21,000 titles) in the world, accessible to researchers in any locality. A free PDF service is maintained to provide researchers in library-poor areas with access to the technical literature.

  16. Competency Interpersonal and Communication Skills Sub Domain Information Sharing

    E-print Network

    Leistikow, Bruce N.

    Competency Interpersonal and Communication Skills Sub Domain Information Sharing Learning Objective 1. Communicates clearly on scientific and medical matters with patients, family, colleagues, and community 2. Demonstrates effective communication in shared decision-making Milestones Year I Year II Year

  17. College of Communication & Information 1345 Circle Park Drive | Suite 302

    E-print Network

    Grissino-Mayer, Henri D.

    standing especially in focused communication niche areas: organizational, interpersonal and healthCollege of Communication & Information 1345 Circle Park Drive | Suite 302 Knoxville, TN 37996 & Communication Studies (CICS) - Awarded grants total $7 million +, NSF, IMLS, Sloan Foundation and more - 2

  18. Communication Efficiency and Congestion of Signal Traffic in Large-Scale Brain Networks

    PubMed Central

    Miši?, Bratislav; Sporns, Olaf; McIntosh, Anthony R.

    2014-01-01

    The complex connectivity of the cerebral cortex suggests that inter-regional communication is a primary function. Using computational modeling, we show that anatomical connectivity may be a major determinant for global information flow in brain networks. A macaque brain network was implemented as a communication network in which signal units flowed between grey matter nodes along white matter paths. Compared to degree-matched surrogate networks, information flow on the macaque brain network was characterized by higher loss rates, faster transit times and lower throughput, suggesting that neural connectivity may be optimized for speed rather than fidelity. Much of global communication was mediated by a “rich club” of hub regions: a sub-graph comprised of high-degree nodes that are more densely interconnected with each other than predicted by chance. First, macaque communication patterns most closely resembled those observed for a synthetic rich club network, but were less similar to those seen in a synthetic small world network, suggesting that the former is a more fundamental feature of brain network topology. Second, rich club regions attracted the most signal traffic and likewise, connections between rich club regions carried more traffic than connections between non-rich club regions. Third, a number of rich club regions were significantly under-congested, suggesting that macaque connectivity actively shapes information flow, funneling traffic towards some nodes and away from others. Together, our results indicate a critical role of the rich club of hub nodes in dynamic aspects of global brain communication. PMID:24415931

  19. A Brief Communication On Job Information

    E-print Network

    Johnson, Deborah G.

    A BRIEF COMMUNICATION ON JOB INFORMATION Dr. Deborah G. Johnson In an earlier issue Auslegung published Kenneth Hclstram's report "Information on Seeking Jobs in Phi­ losophy." While that report is substantially accurate, it «ras prepared... in 1974, and some of the details of the situation have changed. 1) Joining APA Although it is still necessary to join the APA in order to receive Jobs in Philosophy, the APA no longer main­ tains a file of "Applicant Resume Forms." Employers were...

  20. GAS MAIN SENSOR AND COMMUNICATIONS NETWORK SYSTEM

    SciTech Connect

    Hagen Schempf, Ph.D.

    2003-02-27

    Automatika, Inc. was contracted by the Department of Energy (DOE) and with co-funding from the New York Gas Group (NYGAS), to develop an in-pipe natural gas prototype measurement and wireless communications system for assessing and monitoring distribution networks. A prototype system was built for low-pressure cast-iron mains and tested in a spider- and serial-network configuration in a live network in Long Island with the support of Keyspan Energy, Inc. The prototype unit combined sensors capable of monitoring pressure, flow, humidity, temperature and vibration, which were sampled and combined in data-packages in an in-pipe master-slave architecture to collect data from a distributed spider-arrangement, and in a master-repeater-slave configuration in serial or ladder-network arrangements. It was found that the system was capable of performing all data-sampling and collection as expected, yielding interesting results as to flow-dynamics and vibration-detection. Wireless in-pipe communications were shown to be feasible and valuable data was collected in order to determine how to improve on range and data-quality in the future.

  1. Information Communication Technology Planning in Developing Countries

    ERIC Educational Resources Information Center

    Malapile, Sandy; Keengwe, Jared

    2014-01-01

    This article explores major issues related to Information Communication Technology (ICT) in education and technology planning. Using the diffusion of innovation theory, the authors examine technology planning opportunities and challenges in Developing countries (DCs), technology planning trends in schools, and existing technology planning models…

  2. Position Estimation of Tranceivers in Communication Networks

    SciTech Connect

    Kent, C A; Dowla, F U

    2003-10-13

    With the rapid development in wireless sensor networks, there is an important need for transceiver position estimation independent of Global Positioning Systems (GPS) [1,3]. While GPS might be useful for outdoor sensor nodes, it is not for indoor node localization. In this case, position estimation is possible through network range estimates from time-of-flight (TOF) measurements, a technique well suited to large bandwidth physical links, such as in ultra-wideband (UWB) communications. For example, in our UWB systems, with pulse duration less than 200 pico-seconds, range can easily be resolved to less than a foot. Assuming an encoded UWB or spread spectrum physical layer, we developed algorithms and simulation tools to test transceiver position localization. Simulations were designed to lend insight into system characteristics such as position error sensitivities to network geometry, to range estimation errors, and to number of sensor nodes.

  3. The Adoption of International Communications Networks and Electronic Mail into Foreign Language Education

    Microsoft Academic Search

    Seppo Tella

    1992-01-01

    This article reports a study of the possibilities of communications networks and electronic mail (e?mail) in foreign language (FL) teaching. The research model combined FL education and information technologies (communications networks and e?mail). The study was a multisite ethnographic case study, with elements of exploratory, collaborative, change?oriented field?work?based development research. The Finnish participants included six classes (Form 1 or 2)

  4. Acoustic Propagation Considerations for Underwater Acoustic Communications Network Development

    E-print Network

    Zhou, Shengli

    Acoustic Propagation Considerations for Underwater Acoustic Communications Network Development Woods Hole, MA 02543 jpreisig@whoi.edu ABSTRACT Underwater acoustic communications systems are challenged by the characteristics of acoustic propagation through the underwater environment

  5. The Virtual Research and Extension Communication Network (VRECN): An Interactive Learning and Communication Network for Research and Extension Personnel. Concept Paper for the Food & Agriculture Organisation of the United Nations (FAO).

    ERIC Educational Resources Information Center

    Richardson, Don

    A Virtual Research and Extension Communication Network (VRECN) is a set of networked electronic tools facilitating improvement in communication processes and information sharing among stakeholders involved in agricultural development. In developing countries, research and extension personnel within a ministry of agriculture, in consultation and…

  6. Satellite communications and the information decade - An overview

    NASA Astrophysics Data System (ADS)

    Cuccia, C. L.

    1982-01-01

    The paper examines how the information era will utilize satellite communications and digital communication to initiate an era of new users and new satellite services to meet the needs of a highly competitive telecommunications market. Particular consideration is given to microwaves and the development of the chip; communication satellites and information flow; the communication satellite as an information path; the Ku-band direct broadcast satellite; and 30/20 GHz communication satellites.

  7. Information thermodynamics on causal networks.

    PubMed

    Ito, Sosuke; Sagawa, Takahiro

    2013-11-01

    We study nonequilibrium thermodynamics of complex information flows induced by interactions between multiple fluctuating systems. Characterizing nonequilibrium dynamics by causal networks (i.e., Bayesian networks), we obtain novel generalizations of the second law of thermodynamics and the fluctuation theorem, which include an informational quantity characterized by the topology of the causal network. Our result implies that the entropy production in a single system in the presence of multiple other systems is bounded by the information flow between these systems. We demonstrate our general result by a simple model of biochemical adaptation. PMID:24237500

  8. Cooperative Transmission for Wireless Networks Using Mutual-Information Accumulation

    Microsoft Academic Search

    Stark C. Draper; Lingjia Liu; Andreas F. Molisch; Jonathan S. Yedidia

    2011-01-01

    Cooperation between the nodes of wireless multihop networks can increase communication reliability, reduce energy consumption,anddecreaselatency.Thepossibleimprovementsare even greater when nodes perform mutual information accumula- tion. In this paper, we investigate resource allocation for unicast and multicast transmission in such networks. Given a network, a source, and a destination, our objective is to minimize end-to-end transmission delay under energy and bandwidth constraints.

  9. Routing in Cooperative Wireless Networks with Mutual-Information Accumulation

    Microsoft Academic Search

    Stark C. Draper; Lingjia Liu; Andreas F. Molisch; Jonathan S. Yedidia

    2008-01-01

    Cooperation between the nodes of wireless multihop networks can increase communication re- liability, reduce energy consumption, and decrease latency. The possible improvements are even greater when nodes perform mutual-information accumulation, e.g., by using rateless codes. In this paper, we investigate routing problems in such networks. Given a network, a source and a destination, our objective is to minimize end-to-end transmission

  10. Child Rights Information Network Newsletter, 2000-2002.

    ERIC Educational Resources Information Center

    Khan, Andrea, Ed.; Greenwood, Laura, Ed.

    These five newsletter issues communicate activities of the Child Rights Information Network (CRIN) and report on information resources and world-wide activities concerning children and child rights. The March 2000 issue focuses on children's right to education, assessing the matter form a range of differing perspectives, at international and…

  11. Organizational structure and communication networks in a university environment

    NASA Astrophysics Data System (ADS)

    Mathiesen, Joachim; Jamtveit, Bjørn; Sneppen, Kim

    2010-07-01

    The “six degrees of separation” between any two individuals on Earth has become emblematic of the “small world” theme, even though the information conveyed via a chain of human encounters decays very rapidly with increasing chain length, and diffusion of information via this process may be very inefficient in large human organizations. The information flow on a communication network in a large organization, the University of Oslo, has been studied by analyzing email records. The records allow for quantification of communication intensity across organizational levels and between organizational units (referred to as “modules”). We find that the number of email messages within modules scales with module size to the power of 1.29±.06 , and the frequency of communication between individuals decays exponentially with the number of links required upward in the organizational hierarchy before they are connected. Our data also indicates that the number of messages sent by administrative units is proportional to the number of individuals at lower levels in the administrative hierarchy, and the “divergence of information” within modules is associated with this linear relationship. The observed scaling is consistent with a hierarchical system in which individuals far apart in the organization interact little with each other and receive a disproportionate number of messages from higher levels in the administrative hierarchy.

  12. Aquaculture Network Information Center

    NSDL National Science Digital Library

    Given the declining schools of fish in many of the world's oceans, interest in aquaculture has grown exponentially in the past few years. The Aquaculture Network Information Center (ANIC) serves as an electronic gateway to thousands of online aquaculture-related resources, and is hosted by Purdue University and the University of Illinois through the Illinois - Indiana Sea Grant College Program. ANIC was started in 1994, and currently contains links to hundreds of aquaculture publications from around the globe, visual media (such as Power Point presentations), calendars of germane conferences and events, and specialty sections for species and production systems. From the ANIC home page, visitors may join discussion groups about aquaculture (organized by species), learn about different aquaculture cultivation systems, and peruse recent and archive publications from the relevant federal, state, and international agencies. For aquaculture neophytes, a FAQ section will answer ever quandary possible about the world of pond management, the perplexity of pond construction, and the inevitable debates surrounding which form of aquaculture production is most appropriate for different regions of the world.

  13. Queue-length synchronization in communication networks

    NASA Astrophysics Data System (ADS)

    Mukherjee, Satyam; Gupte, Neelima

    2009-05-01

    We study the synchronization in the context of network traffic on a 2-d communication network with local clustering and geographic separations. The network consists of nodes and randomly distributed hubs where the top five hubs ranked according to their coefficient of betweenness centrality (CBC) are connected by random assortative and gradient mechanisms. For multiple message traffic, messages can trap at the high CBC hubs, and congestion can build up on the network with long queues at the congested hubs. The queue lengths are seen to synchronize in the congested phase. Both complete and phase synchronization are seen, between pairs of hubs. In the decongested phase, the pairs start clearing and synchronization is lost. A cascading master-slave relation is seen between the hubs, with the slower hubs (which are slow to decongest) driving the faster ones. These are usually the hubs of high CBC. Similar results are seen for traffic of constant density. Total synchronization between the hubs of high CBC is also seen in the congested regime. Similar behavior is seen for traffic on a network constructed using the Waxman random topology generator. We also demonstrate the existence of phase synchronization in real internet traffic data.

  14. Cooperative UAV-Based Communications Backbone for Sensor Networks

    SciTech Connect

    Roberts, R S

    2001-10-07

    The objective of this project is to investigate the use of unmanned air vehicles (UAVs) as mobile, adaptive communications backbones for ground-based sensor networks. In this type of network, the UAVs provide communication connectivity to sensors that cannot communicate with each other because of terrain, distance, or other geographical constraints. In these situations, UAVs provide a vertical communication path for the sensors, thereby mitigating geographic obstacles often imposed on networks. With the proper use of UAVs, connectivity to a widely disbursed sensor network in rugged terrain is readily achieved. Our investigation has focused on networks where multiple cooperating UAVs are used to form a network backbone. The advantage of using multiple UAVs to form the network backbone is parallelization of sensor connectivity. Many widely spaced or isolated sensors can be connected to the network at once using this approach. In these networks, the UAVs logically partition the sensor network into sub-networks (subnets), with one UAV assigned per subnet. Partitioning the network into subnets allows the UAVs to service sensors in parallel thereby decreasing the sensor-to-network connectivity. A UAV services sensors in its subnet by flying a route (path) through the subnet, uplinking data collected by the sensors, and forwarding the data to a ground station. An additional advantage of using multiple UAVs in the network is that they provide redundancy in the communications backbone, so that the failure of a single UAV does not necessarily imply the loss of the network.

  15. COMMUNICATION NETWORK TCP flow aware adaptive path switching in diffserv

    E-print Network

    Karasan, Ezhan

    flow will be routed. We perform extensive simulations using ns-2 in order to demonstrate the viabilityCOMMUNICATION NETWORK TCP flow aware adaptive path switching in diffserv enabled MPLS networks Onur

  16. Building a Unified Information Network.

    ERIC Educational Resources Information Center

    Avram, Henriette D.

    1988-01-01

    Discusses cooperative efforts between research organizations and libraries to create a national information network. Topics discussed include the Linked System Project (LSP); technical processing versus reference and research functions; Open Systems Interconnection (OSI) Reference Model; the National Science Foundation Network (NSFNET); and…

  17. Description of a method to support public health information management: organizational network analysis

    PubMed Central

    Merrill, Jacqueline; Bakken, Suzanne; Rockoff, Maxine; Gebbie, Kristine; Carley, Kathleen

    2007-01-01

    In this case study we describe a method that has potential to provide systematic support for public health information management. Public health agencies depend on specialized information that travels throughout an organization via communication networks among employees. Interactions that occur within these networks are poorly understood and are generally unmanaged. We applied organizational network analysis, a method for studying communication networks, to assess the method’s utility to support decision making for public health managers, and to determine what links existed between information use and agency processes. Data on communication links among a health department’s staff was obtained via survey with a 93% response rate, and analyzed using Organizational Risk Analyzer (ORA) software. The findings described the structure of information flow in the department’s communication networks. The analysis succeeded in providing insights into organizational processes which informed public health managers’ strategies to address problems and to take advantage of network strengths. PMID:17098480

  18. Communicable Disease Case Entry Using PDAs and Public Wireless Networks

    PubMed Central

    Lober, WB; Bliss, D; Dockrey, MR; Davidson, AJ; Karras, BT

    2003-01-01

    Concerns about detecting and responding to attacks with biowarfare agents have resulted in the development of deployable case reporting systems, e.g. RSVP1. We implement a proof of concept web-based information system to be used securely from personal digital assistants over public wireless networks, by public health field workers for routine and emergent case reporting. The system collects data for a local health jurisdiction, provides content- and event-based notification, and forwards case reports to the Colorado State communicable disease reporting system (CEDRS). We believe this demonstrates a useful integration of portable and web-based technologies with public health practice. PMID:14728422

  19. A Hybrid Satellite-Terrestrial Approach to Aeronautical Communication Networks

    NASA Technical Reports Server (NTRS)

    Kerczewski, Robert J.; Chomos, Gerald J.; Griner, James H.; Mainger, Steven W.; Martzaklis, Konstantinos S.; Kachmar, Brian A.

    2000-01-01

    Rapid growth in air travel has been projected to continue for the foreseeable future. To maintain a safe and efficient national and global aviation system, significant advances in communications systems supporting aviation are required. Satellites will increasingly play a critical role in the aeronautical communications network. At the same time, current ground-based communications links, primarily very high frequency (VHF), will continue to be employed due to cost advantages and legacy issues. Hence a hybrid satellite-terrestrial network, or group of networks, will emerge. The increased complexity of future aeronautical communications networks dictates that system-level modeling be employed to obtain an optimal system fulfilling a majority of user needs. The NASA Glenn Research Center is investigating the current and potential future state of aeronautical communications, and is developing a simulation and modeling program to research future communications architectures for national and global aeronautical needs. This paper describes the primary requirements, the current infrastructure, and emerging trends of aeronautical communications, including a growing role for satellite communications. The need for a hybrid communications system architecture approach including both satellite and ground-based communications links is explained. Future aeronautical communication network topologies and key issues in simulation and modeling of future aeronautical communications systems are described.

  20. Delay Sensitive Communications over Cognitive Radio Networks

    E-print Network

    Wang, Feng; Zhao, Yuping

    2012-01-01

    Supporting the quality of service of unlicensed users in cognitive radio networks is very challenging, mainly due to dynamic resource availability because of the licensed users' activities. In this paper, we study the optimal admission control and channel allocation decisions in cognitive overlay networks in order to support delay sensitive communications of unlicensed users. We formulate it as a Markov decision process problem, and solve it by transforming the original formulation into a stochastic shortest path problem. We then propose a simple heuristic control policy, which includes a threshold-based admission control scheme and and a largest-delay-first channel allocation scheme, and prove the optimality of the largest-delay-first channel allocation scheme. We further propose an improved policy using the rollout algorithm. By comparing the performance of both proposed policies with the upper-bound of the maximum revenue, we show that our policies achieve close-to-optimal performance with low complexities...

  1. MOST network system supporting full-duplexing communication

    Microsoft Academic Search

    Sang-Yub Lee; Sang-Hyun Park; Hyo-Sub Choi; Chul Dong Lee

    2012-01-01

    Increasing network reliability and reducing the fault tolerance of Media Oriented System Transport (MOST) network which has been adopted by major car maker such as BMW, AUDI, as in-vehicle backbone network has to be employed the full duplexing configuration. In this paper, proposed MOST network system is applied to two communication ports which enable to provide redundant path. Thus proposed

  2. GAS MAIN SENSOR AND COMMUNICATIONS NETWORK SYSTEM

    SciTech Connect

    Hagen Schempf

    2004-09-30

    Automatika, Inc. was contracted by the Department of Energy (DOE) and with co-funding from the New York Gas Group (NYGAS), to develop an in-pipe natural gas prototype measurement and wireless communications system for assessing and monitoring distribution networks. In Phase II of this three-phase program, an improved prototype system was built for low-pressure cast-iron and high-pressure steel (including a no-blow installation system) mains and tested in a serial-network configuration in a live network in Long Island with the support of Keyspan Energy, Inc. The experiment was carried out in several open-hole excavations over a multi-day period. The prototype units (3 total) combined sensors capable of monitoring pressure, flow, humidity, temperature and vibration, which were sampled and combined in data-packages in an in-pipe master-repeater-slave configuration in serial or ladder-network arrangements. It was verified that the system was capable of performing all data-sampling, data-storage and collection as expected, yielding interesting results as to flow-dynamics and vibration-detection. Wireless in-pipe communications were shown to be feasible and the system was demonstrated to run off in-ground battery- and above-ground solar power. The remote datalogger access and storage-card features were demonstrated and used to log and post-process system data. Real-time data-display on an updated Phase-I GUI was used for in-field demonstration and troubleshooting.

  3. Information needs for risk management/communication

    SciTech Connect

    Bennett, D.A. [Environmental Protection Agency, Washington, DC (United States)

    1990-12-31

    The hazardous waste cleanup program under the Comprehensive Environmental Response, Compensation, and Liability Act (Superfund) is delegated to the ten Regions of the US Environmental Protection Agency (EPA) and has, to date, identified more than 33,000 sites for consideration. The size and complexity of the program places great demands on those who would provide information to achieve national consistency in application of risk assessment while meeting site-specific needs for risk management and risk communication.

  4. Functional boxes, communication complexity and information causality

    E-print Network

    Guoming Wang

    2011-09-28

    We propose a class of nonlocal boxes named functional boxes which include a generalization of the Popescu-Rohrlich(PR) box as a special case. We show that every functional box corresponding to an additively inseparable function can make communication complexity trivial and thus seems unlikely to exist in nature. Then we relate general nonlocal boxes to these functional boxes, and derive several limits on them from the principle of information causality.

  5. Supporting healthcare communication enabled by Information and Communication Technology: can HCI and related cognitive aspects help?

    Microsoft Academic Search

    Laurence Alpay; Pieter Toussaint; Bertie Zwetsloot-Schonk

    2004-01-01

    Communication in healthcare makes up an important part of the healthcare professionals' daily practices. Communication encompasses different forms of interaction and dissemination of health-related information, and takes place in contexts such as patient\\/healthcare professional relationships, and collaborative care. While Information and Communication Technology (ICT) offers a useful means to support the accessibility, the exchange and the sharing of information, the

  6. Automatic Generation of Social Network Data from Electronic-Mail Communications

    Microsoft Academic Search

    Jason Yee; Robert F. Mills; Gilbert L. Peterson; Summer E. Bartczak

    Most organizations have formal and informal elements. Formal structures are usually documented in organizational charts showing chain of command, levels of authority, and personnel resources. The actual effectiveness of the organization or specific ind ividuals may actually depend on informal structures and internal communication networks. These are by definition personality-dependent and may provide significant insight into how work actually gets

  7. Opportunistic Communications for Networked Controlled Systems of Autonomous Vehicles

    E-print Network

    Baras, John S.

    Opportunistic Communications for Networked Controlled Systems of Autonomous Vehicles Hua Chen of communication connectivity in networks of autonomous vehicles. It is difficult to overcome deep fading from time of autonomous vehicles with energy con- sumption and total operation time constraints in an adversarial

  8. Communication Performance over a Gigabit Ethernet Network. Paul A. Farrell

    E-print Network

    Farrell, Paul A.

    of Gigabit Ethernet technology and study the end-to-end Gigabit Ethernet communication bandwidth and latencyCommunication Performance over a Gigabit Ethernet Network. Paul A. Farrell Hong Ong Department@mcs.kent.edu Abstract Cluster computing imposes heavy demands on the com- munication network. Gigabit Ethernet

  9. Autosophy data compression accelerates and encrypts network communications

    Microsoft Academic Search

    Klaus Holtz

    1995-01-01

    Data compression has evolved rapidly from simple disc file compression software to integrated compression chipsets which will become standard parts in most future communications networks. The application is almost irresistible. If simple chipsets can indeed double or triple network throughput and provide an optional unbreakable encryption code, then conventional data communications will soon become uncompetitive. While data compression can greatly

  10. Multiple communication in multi-hop radio networks

    Microsoft Academic Search

    Reuven Bar-Yehudaf; Amos IsraeliS

    1989-01-01

    Two tasks of communication in a multi-hop synchronous radio network are con- sidered: point-to-point communication and broadcast (sending a message to all nodes of a network). Efficient protocols for both problems are presented. Even though the protocols are probabilistic, it is shown how to acknowledge messages deterministically. Let n, D, and ? be the number of nodes, the diameter and

  11. Hot Topic Session: Optimization and Control of Communication Networks

    E-print Network

    Low, Steven H.

    to analyze, interpret, or design a communication system, for both forward- engineering and reverse the classical network flow problem and provided an emerging framework to design resource allocation algorithmsHot Topic Session: Optimization and Control of Communication Networks ACM Sigmetrics 2005

  12. A new definition of survivability of communication networks

    Microsoft Academic Search

    TONG ZE JIANG

    1991-01-01

    It is suggested that the most important and reasonable parameter of a communication network is the traffic capacity, which might be selected to measure the survivability. It is concluded that the definition of survivability based on traffic flow can be used to evaluate or design a military communication network conveniently. It includes the old definition based on connectivity and is

  13. AUV Control and Communication using Underwater Acoustic Networks

    Microsoft Academic Search

    E. R. B. Marques; J. Pinto; S. Kragelund; P. S. Dias; L. Madureira; A. Sousa; M. Correia; H. Ferreira; R. Goncalves; R. Martins; D. P. Horner; A. J. Healey; G. M. Goncalves; J. B. Sousa

    2007-01-01

    Underwater acoustic networks can be quite effective to establish communication links between autonomous underwater vehicles (AUVs) and other vehicles or control units, enabling complex vehicle applications and control scenarios. A communications and control framework to support the use of underwater acoustic networks and sample application scenarios are described for single and multi-AUV operation.

  14. Large Scale Distributed Disaster Information System based on MANET and Overlay Network

    Microsoft Academic Search

    Yoshitaka Shibata; Hiroaki Yuze; Tsuyoshi Hoshikawa; Kazuo Takahata; Nobuhiro Sawano

    2007-01-01

    In the case of large scale disaster, such as earthquake, volcanic explosion, sea wave, more robust and flexible nation-wide disaster information network is required not only for governmental supporters but also residents and volunteers than business oriented network to communicate each other even though some parts of the network and information system are destroyed and disconnected. In this paper, we

  15. Multi-agent Learning Approach to WWW Information Retrieval using Neural Network

    E-print Network

    Yoo, SukIn

    results in ineffective and wasteful competition for network resources with considerable communication costMulti-agent Learning Approach to WWW Information Retrieval using Neural Network Yong S. Choi a neural network mechanism. Our approach makes it possible to discover information sources that will give

  16. An integrated information management network

    Microsoft Academic Search

    Manfred Fehr

    1996-01-01

    The specific microsystems pertaining to process safety management and energy management may be considered part of the integrated organizational information management macrosystem where they have to compete with various other microsystems for importance and resources. An empirical exercise has been conducted to illustrate an integrated busines management network with six levels of hierarchy and the corresponding information flow. Each level

  17. A power line communication network infrastructure for the smart home

    Microsoft Academic Search

    Yu-Ju Lin; H. A. Latchman; Minkyu Lee; S. Katar

    2002-01-01

    Low voltage electrical wiring has largely been dismissed as too noisy and unpredictable to support high-speed communication signals. Advances in communication and modulation methodologies as well as in adaptive digital signal processing and error detection and correction have spawned novel protocols capable of supporting power line communication networks at speeds comparable to wired LANs. We motivate the use of power

  18. Mitigating the Hospital Area Communication's Interference using Cognitive Radio Networks

    E-print Network

    Paris-Sud XI, Université de

    Mitigating the Hospital Area Communication's Interference using Cognitive Radio Networks Dramane-quality communication services and mitigating radio interferences in hospital environment. In this paper, we discuss.khalife@thalesgroup.com. Abstract--The communication infrastructures and devices in hospitals are becoming increasingly wireless

  19. Whether Information Network Supplements Friendship Network

    E-print Network

    Miao, Lili; Nie, Da-Chen; Cai, Shi-Min

    2014-01-01

    Homophily is a significant mechanism for link prediction in complex network, of which principle describes that people with similar profiles or experiences tend to tie with each other. In a multi-relationship network, friendship among people has been utilized to reinforce similarity of taste for recommendation system whose basic idea is similar to homophily, yet how the taste inversely affects friendship prediction is little discussed. This paper contributes to address the issue by analyzing two benchmark datasets both including user's behavioral information of taste and friendship based on the principle of homophily. It can be found that the creation of friendship tightly associates with personal taste. Especially, the behavioral information of taste involving with popular objects is much more effective to improve the performance of friendship prediction. However, this result seems to be contradictory to the finding in [Q.M. Zhang, et al., PLoS ONE 8(2013)e62624] that the behavior information of taste involvi...

  20. A cross-domain communication resource scheduling method for grid-enabled communication networks

    NASA Astrophysics Data System (ADS)

    Zheng, Xiangquan; Wen, Xiang; Zhang, Yongding

    2011-10-01

    To support a wide range of different grid applications in environments where various heterogeneous communication networks coexist, it is important to enable advanced capabilities in on-demand and dynamical integration and efficient co-share with cross-domain heterogeneous communication resource, thus providing communication services which are impossible for single communication resource to afford. Based on plug-and-play co-share and soft integration with communication resource, Grid-enabled communication network is flexibly built up to provide on-demand communication services for gird applications with various requirements on quality of service. Based on the analysis of joint job and communication resource scheduling in grid-enabled communication networks (GECN), this paper presents a cross multi-domain communication resource cooperatively scheduling method and describes the main processes such as traffic requirement resolution for communication services, cross multi-domain negotiation on communication resource, on-demand communication resource scheduling, and so on. The presented method is to afford communication service capability to cross-domain traffic delivery in GECNs. Further research work towards validation and implement of the presented method is pointed out at last.

  1. Gas Main Sensor and Communications Network System

    SciTech Connect

    Hagen Schempf

    2006-05-31

    Automatika, Inc. was contracted by the Department of Energy (DOE) and with co-funding from the Northeast Gas Association (NGA), to develop an in-pipe natural gas prototype measurement and wireless communications system for assessing and monitoring distribution networks. This projected was completed in April 2006, and culminated in the installation of more than 2 dozen GasNet nodes in both low- and high-pressure cast-iron and steel mains owned by multiple utilities in the northeastern US. Utilities are currently logging data (off-line) and monitoring data in real time from single and multiple networked sensors over cellular networks and collecting data using wireless bluetooth PDA systems. The system was designed to be modular, using in-pipe sensor-wands capable of measuring, flow, pressure, temperature, water-content and vibration. Internal antennae allowed for the use of the pipe-internals as a waveguide for setting up a sensor network to collect data from multiple nodes simultaneously. Sensor nodes were designed to be installed with low- and no-blow techniques and tools. Using a multi-drop bus technique with a custom protocol, all electronics were designed to be buriable and allow for on-board data-collection (SD-card), wireless relaying and cellular network forwarding. Installation options afforded by the design included direct-burial and external polemounted variants. Power was provided by one or more batteries, direct AC-power (Class I Div.2) and solar-array. The utilities are currently in a data-collection phase and intend to use the collected (and processed) data to make capital improvement decisions, compare it to Stoner model predictions and evaluate the use of such a system for future expansion, technology-improvement and commercialization starting later in 2006.

  2. Short communication: Use of genomic and metabolic information as well as milk performance records for prediction of subclinical ketosis risk via artificial neural networks.

    PubMed

    Ehret, A; Hochstuhl, D; Krattenmacher, N; Tetens, J; Klein, M S; Gronwald, W; Thaller, G

    2015-01-01

    Subclinical ketosis is one of the most prevalent metabolic disorders in high-producing dairy cows during early lactation. This renders its early detection and prevention important for both economical and animal-welfare reasons. Construction of reliable predictive models is challenging, because traits like ketosis are commonly affected by multiple factors. In this context, machine learning methods offer great advantages because of their universal learning ability and flexibility in integrating various sorts of data. Here, an artificial-neural-network approach was applied to investigate the utility of metabolic, genetic, and milk performance data for the prediction of milk levels of ?-hydroxybutyrate within and across consecutive weeks postpartum. Data were collected from 218 dairy cows during their first 5wk in milk. All animals were genotyped with a 50,000 SNP panel, and weekly information on the concentrations of the milk metabolites glycerophosphocholine and phosphocholine as well as milk composition data (milk yield, fat and protein percentage) was available. The concentration of ?-hydroxybutyric acid in milk was used as target variable in all prediction models. Average correlations between observed and predicted target values up to 0.643 could be obtained, if milk metabolite and routine milk recording data were combined for prediction at the same day within weeks. Predictive performance of metabolic as well as milk performance-based models was higher than that of models based on genetic information. PMID:25465566

  3. [Forensic evidence-based medicine in computer communication networks].

    PubMed

    Qiu, Yun-Liang; Peng, Ming-Qi

    2013-12-01

    As an important component of judicial expertise, forensic science is broad and highly specialized. With development of network technology, increasement of information resources, and improvement of people's legal consciousness, forensic scientists encounter many new problems, and have been required to meet higher evidentiary standards in litigation. In view of this, evidence-based concept should be established in forensic medicine. We should find the most suitable method in forensic science field and other related area to solve specific problems in the evidence-based mode. Evidence-based practice can solve the problems in legal medical field, and it will play a great role in promoting the progress and development of forensic science. This article reviews the basic theory of evidence-based medicine and its effect, way, method, and evaluation in the forensic medicine in order to discuss the application value of forensic evidence-based medicine in computer communication networks. PMID:24665620

  4. Alternative Technologies for Information Networks.

    ERIC Educational Resources Information Center

    Farquhar, J. A.; Dei Rossi, J. A.

    The paper concerns some of the economic considerations inherent in designing user services that incorporate various communication systems. It describes three such services considered important in providing information to the biomedical community comprised of practicing physicians and those engaged in teaching and research, as well as other…

  5. IEEE Communications Magazine November 2006142 0163-6804/06/$20.00 2006 IEEE TOPICS IN AD HOC AND SENSOR NETWORKS

    E-print Network

    Liu, Yonghe

    Conventional wireless sensor networks rely mostly on simple scalar data (such as tempera- ture or humidity AND SENSOR NETWORKS INTRODUCTION Despite the tremendous progress in sensor design and wireless communications recently, the integration of information-rich content with the potential of distributed sensor networks

  6. Towards Understanding of Complex Communication Networks: Performance, Phase Transitions & Control

    Microsoft Academic Search

    V. Marbukh

    The paper discusses a possibility of phase transitions and metastability in various types of complex communication networks as well as implication of these phenomena for network performance evaluation and control. Specific cases include connection-oriented networks with dynamic routing, TCP\\/IP networks under random flow arrivals\\/departures, and multiservice wireless cellular networks. Despite reasons for phase transitions and metastability in different types of

  7. Information-Seeking Behavior in Intercultural and Intergroup Communication.

    ERIC Educational Resources Information Center

    Baldwin, John R.; Hunt, Stephen K.

    2002-01-01

    Reviews the current state of information-seeking research and theory in the field of intercultural communication. Draws distinctions between different types of intercultural communication research. Discusses how information seeking might be relevant across types and different between types of intercultural communication. Recommends directions for…

  8. Integration of Auditory and Visual Communication Information in the Primate Ventrolateral Prefrontal Cortex

    PubMed Central

    Sugihara, Tadashi; Diltz, Mark D.; Averbeck, Bruno B.; Romanski, Lizabeth M.

    2009-01-01

    The integration of auditory and visual stimuli is crucial for recognizing objects, communicating effectively, and navigating through our complex world. Although the frontal lobes are involved in memory, communication, and language, there has been no evidence that the integration of communication information occurs at the single-cell level in the frontal lobes. Here, we show that neurons in the macaque ventrolateral prefrontal cortex (VLPFC) integrate audiovisual communication stimuli. The multisensory interactions included both enhancement and suppression of a predominantly auditory or a predominantly visual response, although multisensory suppression was the more common mode of response. The multisensory neurons were distributed across the VLPFC and within previously identified unimodal auditory and visual regions (O’Scalaidhe et al., 1997; Romanski and Goldman-Rakic, 2002). Thus, our study demonstrates, for the first time, that single prefrontal neurons integrate communication information from the auditory and visual domains, suggesting that these neurons are an important node in the cortical network responsible for communication. PMID:17065454

  9. Communication and cooperation in underwater acoustic networks

    NASA Astrophysics Data System (ADS)

    Yerramalli, Srinivas

    In this thesis, we present a study of several problems related to underwater point to point communications and network formation. We explore techniques to improve the achievable data rate on a point to point link using better physical layer techniques and then study sensor cooperation which improves the throughput and reliability in an underwater network. Robust point-to-point communications in underwater networks has become increasingly critical in several military and civilian applications related to underwater communications. We present several physical layer signaling and detection techniques tailored to the underwater channel model to improve the reliability of data detection. First, a simplified underwater channel model in which the time scale distortion on each path is assumed to be the same (single scale channel model in contrast to a more general multi scale model). A novel technique, which exploits the nature of OFDM signaling and the time scale distortion, called Partial FFT Demodulation is derived. It is observed that this new technique has some unique interference suppression properties and performs better than traditional equalizers in several scenarios of interest. Next, we consider the multi scale model for the underwater channel and assume that single scale processing is performed at the receiver. We then derive optimized front end pre-processing techniques to reduce the interference caused during single scale processing of signals transmitted on a multi-scale channel. We then propose an improvised channel estimation technique using dictionary optimization methods for compressive sensing and show that significant performance gains can be obtained using this technique. In the next part of this thesis, we consider the problem of sensor node cooperation among rational nodes whose objective is to improve their individual data rates. We first consider the problem of transmitter cooperation in a multiple access channel and investigate the stability of the grand coalition of transmitters using tools from cooperative game theory and show that the grand coalition in both the asymptotic regimes of high and low SNR. Towards studying the problem of receiver cooperation for a broadcast channel, we propose a game theoretic model for the broadcast channel and then derive a game theoretic duality between the multiple access and the broadcast channel and show that how the equilibria of the broadcast channel are related to the multiple access channel and vice versa.

  10. A Tradeoff between Information and Communication in Broadcast Protocols

    Microsoft Academic Search

    Baruch Awerbuch; Oded Goldreich; David Peleg; Ronen Vainish

    1988-01-01

    This paper concerns the message complexity of broadcast in arbitrary point-to-point communication networks. Broadcast is a task initiated by a single processor that wishes to convey a message to all processors in the network. We assume the widely accepted model of communication\\u000a networks, in which each processor initially knows the identity of its neighbors, but does not know the entire

  11. Software architecture for network communication. Technical report, 7 August 1984-6 August 1987

    SciTech Connect

    Anderson, D.P.

    1987-11-30

    A distributed system is based on a layered set of abstractions of network communication. At a low level, current distributed systems use primitives such as datagrams, request/reply message passing, reliable virtual circuits, or a combination of these. Future distributed systems will use high-performance large-scale communication networks, and will support a range of communication-intensive applications. What are the appropriate communication abstractions for such systems. In answer to this question, the author developed a communication abstraction called Real-Time Message Streams (RMS). An RMS is a simplex (unidirectional) stream with several performance and security parameters. These parameters express 1) the needs of RMS clients (user programs and communication protocols), and 2) the capabilities of the RMS provider (network and higher layers). This information can be used in two ways. First, RMS providers can eliminate unnecessary or redundant work, and can optimally schedule resources such as network bandwidth and CPU. Second, the RMS client can use the parameters to select optimal methods for achieving whatever reliability and flow control are needed. RMS is the communication primitive of the DASH distributed system currently being developed at UC Berkeley. This paper describes 1) the RMS abstraction itself, 2) the role of RMS and DASH communication architecture, and 3) techniques and algorithms for providing RMS at various system levels.

  12. Power-law behavior in complex organizational communication networks during crisis

    NASA Astrophysics Data System (ADS)

    Uddin, Shahadat; Murshed, Shahriar Tanvir Hasan; Hossain, Liaquat

    2011-08-01

    Communication networks can be described as patterns of contacts which are created due to the flow of messages and information shared among participating actors. Contemporary organizations are now commonly viewed as dynamic systems of adaptation and evolution containing several parts, which interact with one another both in internal and in external environment. Although there is limited consensus among researchers on the precise definition of organizational crisis, there is evidence of shared meaning: crisis produces individual crisis, crisis can be associated with positive or negative conditions, crises can be situations having been precipitated quickly or suddenly or situations that have developed over time and are predictable etc. In this research, we study the power-law behavior of an organizational email communication network during crisis from complexity perspective. Power law simply describes that, the probability that a randomly selected node has k links (i.e. degree k) follows P(k)?k, where ? is the degree exponent. We used social network analysis tools and techniques to analyze the email communication dataset. We tested two propositions: (1) as organization goes through crisis, a few actors, who are prominent or more active, will become central, and (2) the daily communication network as well as the actors in the communication network exhibit power-law behavior. Our preliminary results support these two propositions. The outcome of this study may provide significant advancement in exploring organizational communication network behavior during crisis.

  13. Statistical characterizers of transport in communication networks

    NASA Astrophysics Data System (ADS)

    Mukherjee, Satyam; Gupte, Neelima; Mukherjee, Gautam

    2010-04-01

    We identify the statistical characterizers of congestion and decongestion for message transport in model communication lattices. These turn out to be the travel time distributions, which are Gaussian in the congested phase, and logarithmic normal in the decongested phase. Our results are demonstrated for two-dimensional lattices, such the Waxman graph, and for lattices with local clustering and geographic separations, gradient connections, as well as for a one-dimensional ring lattice with random assortative connections. The behavior of the distribution identifies the congested and decongested phase correctly for these distinct network topologies and decongestion strategies. The waiting time distributions of the systems also show identical signatures of the congested and decongested phases. The distributions are explained using a stochastic differential equation to model the transport.

  14. Emerging information technology and the expanding role of technical communicators 

    E-print Network

    McGuire, Richard Charles

    1996-01-01

    Emerging information technology is expanding the role of technical communicators. Functionality present in software tools contributes to a re-definition of what tasks technical communicators currently perform and how they will use object management...

  15. Scaling of load in communications networks Onuttom Narayan1

    E-print Network

    California at Santa Cruz, University of

    Scaling of load in communications networks Onuttom Narayan1 and Iraj Saniee2 1 Department that the load at each node in a preferential attachment network scales as a power of the degree of the node. For a network whose degree distribution is p(k) k- , we show that the load is l(k) k with = - 1, implying

  16. Communication Architecture Design for Real-Time Networked Control Systems

    Microsoft Academic Search

    Yu-Chu Tian; Qing-Long Han; C. Fidge; M. O. Tade; Tianlong Gu

    2006-01-01

    Networked control over data networks has received increasing attention in recent years. Among many problems in networked control systems (NCSs) is the need to reduce control latency and jitter and to deal with packet dropouts. This paper introduces our recent progress on a queuing communication architecture for real-time NCS applications, and simple strategies for dealing with packet dropouts. Case studies

  17. ECO: Efficient Collective Operations for Communication on Heterogeneous Networks

    Microsoft Academic Search

    Bruce B. Lowekamp; Adam Beguelinl

    1996-01-01

    PVM and other distributed computing systems have enabled the use of networks of workstationsfor parallel computation, but their approach of treating all networks as collectionsof point-to-point connections does not promote efficient communication---particularly collectivecommunication. The Efficient Collective Operations package (ECO) contains programswhich solve this problem by analyzing the network and establishing efficient communicationpatterns. These patterns are used by ECO's library ...

  18. On Communication Security in Wireless Ad-Hoc Sensor Networks

    Microsoft Academic Search

    Sasha Slijepcevic; Miodrag Potkonjak; Vlasios Tsiatsis; Scott Zimbeck; Mani B. Srivastava

    2002-01-01

    Networks of wireless microsensors for monitoring physical environments have emerged as an important new application area for wireless technology. Key attributes of these new types of networked systems are the severely constrained computational and energy resources, and an ad hoc operational environment. This paper is a study of the communication security aspects of these networks. Resource limitations and specific architecture

  19. Hindawi Publishing Corporation EURASIP Journal on Wireless Communications and Networking

    E-print Network

    Wichmann, Felix

    be also based on other radio access bearer techniques as, for example, single frequency networks of DVB¨at Berlin, Einsteinufer 17, 10587 Berlin, Germany 3 Ericsson Research, Mobile Multimedia Networks, EricssonHindawi Publishing Corporation EURASIP Journal on Wireless Communications and Networking Volume

  20. Unreduced Dynamic Complexity: Towards the Unified Science of Intelligent Communication Networks and Software

    E-print Network

    Andrei P. Kirilyuk

    2006-03-16

    Operation of autonomic communication networks with complicated user-oriented functions should be described as unreduced many-body interaction process. The latter gives rise to complex-dynamic behaviour including fractally structured hierarchy of chaotically changing realisations. We recall the main results of the universal science of complexity (physics/9806002) based on the unreduced interaction problem solution and its application to various real systems, from nanobiosystems (physics/0412097, physics/0502133) and quantum devices (physics/0211071) to intelligent networks (physics/0412058) and emerging consciousness (physics/0409140). We concentrate then on applications to autonomic communication leading to fundamentally substantiated, exact science of intelligent communication and software. It aims at unification of the whole diversity of complex information system behaviour, similar to the conventional, "Newtonian" science order for sequential, regular models of system dynamics. Basic principles and first applications of the unified science of complex-dynamic communication networks and software are outlined to demonstrate its advantages and emerging practical perspectives.

  1. Next generation information communication infrastructure and case studies for future power systems

    NASA Astrophysics Data System (ADS)

    Qiu, Bin

    As power industry enters the new century, powerful driving forces, uncertainties and new functions are compelling electric utilities to make dramatic changes in their information communication infrastructure. Expanding network services such as real time measurement and monitoring are also driving the need for more bandwidth in the communication network. These needs will grow further as new remote real-time protection and control applications become more feasible and pervasive. This dissertation addresses two main issues for the future power system information infrastructure: communication network infrastructure and associated power system applications. Optical networks no doubt will become the predominant data transmission media for next generation power system communication. The rapid development of fiber optic network technology poses new challenges in the areas of topology design, network management and real time applications. Based on advanced fiber optic technologies, an all-fiber network is investigated and proposed. The study will cover the system architecture and data exchange protocol aspects. High bandwidth, robust optical networks could provide great opportunities to the power system for better service and efficient operation. In the dissertation, different applications are investigated. One of the typical applications is the SCADA information accessing system. An Internet-based application for the substation automation system will be presented. VLSI (Very Large Scale Integration) technology is also used for one-line diagrams auto-generation. High transition rate and low latency optical network is especially suitable for power system real time control. In the dissertation, a new local area network based Load Shedding Controller (LSC) for isolated power system will be presented. By using PMU (Phasor Measurement Unit) and fiber optic network, an AGE (Area Generation Error) based accurate wide area load shedding scheme will also be proposed. The objective is to shed the load in the limited area with minimum disturbance.

  2. A unified network approach to the control of survivable multimedia communication networks

    Microsoft Academic Search

    S. Adams; R. Mouldin; B. Demeyer; J. Hardy

    1990-01-01

    A major thrust in modern military communication systems is to integrate all of the existing and future propagation media resources in a communication system with the objective of providing more reliable, survivable, enduring communication system performance in a stressed environment. An analysis of the objectives, including survivability, network throughput, and delay, to be achieved by integrating communication resources to create

  3. Network Information Management Subsystem

    NASA Technical Reports Server (NTRS)

    Chatburn, C. C.

    1985-01-01

    The Deep Space Network is implementing a distributed data base management system in which the data are shared among several applications and the host machines are not totally dedicated to a particular application. Since the data and resources are to be shared, the equipment must be operated carefully so that the resources are shared equitably. The current status of the project is discussed and policies, roles, and guidelines are recommended for the organizations involved in the project.

  4. Network security system for health and medical information using smart IC card

    NASA Astrophysics Data System (ADS)

    Kanai, Yoichi; Yachida, Masuyoshi; Yoshikawa, Hiroharu; Yamaguchi, Masahiro; Ohyama, Nagaaki

    1998-07-01

    A new network security protocol that uses smart IC cards has been designed to assure the integrity and privacy of medical information in communication over a non-secure network. Secure communication software has been implemented as a library based on this protocol, which is called the Integrated Secure Communication Layer (ISCL), and has been incorporated into information systems of the National Cancer Center Hospitals and the Health Service Center of the Tokyo Institute of Technology. Both systems have succeeded in communicating digital medical information securely.

  5. Research of information dissemination model based on Network Centric Warfare

    Microsoft Academic Search

    Yong Yao; Zhi Li

    2010-01-01

    Network Centric Warfare (NCW) concept has been developed over ten years, but some misunderstanding is still in existence. The Command and Control, Battle Management, Communications (C2BMC) system of U.S. Ballistic Missile Defense System is one of the cases which employs NCW concept successfully. In this paper, the successful reason was found by the work of information dissemination modeling and then

  6. Ultraviolet Communication Network Modeling and Analysis

    E-print Network

    Wang, Leijie

    2011-01-01

    and Optics - Free Space Laser Communications IX, San Diego,in free-space optical communication using laser diode [12].laser or a LED array could be employed for long distance free-space UV communication,

  7. A Framework for In-Network Management in Heterogeneous Future Communication Networks

    Microsoft Academic Search

    Christopher Foley; Sasitharan Balasubramaniam; Eamonn Power; Miguel Ponce De Leon; Dmitri Botvich; Dominique Dudkowski; Giorgio Nunzi; Chiara Mingardi

    2008-01-01

    Future communication networks will be composed of a diversity of highly heterogeneous network variants, ranging from energy\\u000a constrained wireless sensor networks to large-scale wide area networks. The fact that the size and complexity of such networks\\u000a will experience tremendous growth will eventually render existing traditional network management paradigms unfeasible. We\\u000a propose the radically new paradigm of in-network management, which targets

  8. New-age patient communications through social networks.

    PubMed

    Ogburn, Kelin M; Messias, Erick; Buckley, Peter F

    2011-01-01

    Suicide prevention continues to be a significant clinical challenge in the care of psychiatric patients, particularly among youth. New patterns of interactions and communications using online social networks create opportunities for persons to indicate their mood, their opinions, and also to express ideation and plans about suicide. We report a case of a suicide attempt and how communications through online social networks initiated treatment and affected its outcome. We discuss advantages and challenges to clinicians regarding use social networks and electronic communication in patient care. PMID:21596215

  9. Pacific Islands Mass Communications; Selected Information Sources.

    ERIC Educational Resources Information Center

    Richstad, Jim; McMillan, Michael

    1977-01-01

    Presents a bibliography of materials on such area of mass communications in the Pacific Islands as broadcasting, radio and television, cinema, communication research, mass media in education, Honululu Media Council, newspapers and newspapermen, and printing and satellite communication. (JEG)

  10. Citation networks in information science

    Microsoft Academic Search

    Irina V. Marshakova

    1981-01-01

    The method of co-citation analysis is used to build citation networks in information science. As data base the first 13 volumes (1961–1973) of the leading Soviet journal in the field (Nauchno-tekhnicheskaya Informatsiya) were used. The results reveal the topical structure of information science, the communities of authors and the names of single leading scientists. The evaluation of scientists' work is

  11. Foundations and Trends R Communications and Information Theory

    E-print Network

    Merhav, Neri

    Foundations and Trends R in Communications and Information Theory Vol. 6, Nos. 1­2 (2009) 1­212 c 2010 N. Merhav DOI: 10.1561/0100000052 Statistical Physics and Information Theory By Neri Merhav in Communications and Information Theory Vol. 6, Nos. 1­2 (2009) 1­212 c 2010 N. Merhav DOI: 10

  12. An information statistics approach to data stream and communication complexity

    Microsoft Academic Search

    Ziv Bar-yossef; T. S. Jayram; Ravi Kumar; D. Sivakumar

    2004-01-01

    Abstract We present a new method,for proving strong lower bounds,in communication,complexity. This method,is based on the notion of the conditional information complexity,of a function which is the minimum,amount of information,about the inputs that has to be revealed by a communication,protocol for the function. While conditional information complexity is a lower bound on communication complexity, we show that it also admits

  13. Distributed Relay Selection and Power Control for Multiuser Cooperative Communication Networks Using Buyer/Seller Game

    E-print Network

    Liu, K. J. Ray

    in cooperative communications depend on careful resource allocation such as relay selection and power controlDistributed Relay Selection and Power Control for Multiuser Cooperative Communication Networks framework over multiuser cooperative communication networks to stimulate cooperation and improve the system

  14. Communication Algorithms for Wireless Ad Hoc Networks

    E-print Network

    Viqar, Saira

    2012-10-19

    ,40,41] or broadcasting [7,44] also require accurate and up-to-date knowl- edge about neighbor nodes. For example, [45] implements coordinate based routing by assuming nodes know the location of their two-hop neighbors. Similarly, [40] describes a routing algorithm... for multi-hop wireless network that assumes one-hop neighbor information. Contributions. The main contributions of this work are: 1. We describe a speci cation for a reliable neighbor discovery layer. We consider two di erent progress conditions. 2. We...

  15. Design and analysis of the satellite laser communications network

    NASA Astrophysics Data System (ADS)

    Ren, Pei-an; Qian, Fengchen; Liu, Qiang; Jin, Linlin

    2015-02-01

    A satellite laser communications network structure with two layers and multiple domains has been proposed, which performance has been simulated by OPENT. To simulation, we design several OPNET models of the network's components based on a satellite constellation with two layers and multiple domains, as network model, node model, MAC layer protocol and optical antenna model. The network model consists of core layer and access layer. The core network consists of four geostationary orbit (GEO) satellites which are uniformly distributed in the geostationary orbit. The access network consists of 6 low Earth orbit (LEO) satellites which is the walker delta (walk-?) constellation with three orbit planes. In access layer, each plane has two satellites, and the constellation is stably. The satellite constellation presented for space laser network can meet the demand of coverage in the middle and low latitude by a few satellites. Also several terminal device models such as the space laser transmitter, receiver, protocol layer module and optical antenna have been designed according to the inter-satellite links in different orbits t from GEO to LEO or GEO to ground. The influence to network of different transmitting throughput, receiving throughput, network protocol and average time delay are simulated. Simulation results of network coverage, connectivity and traffic load performance in different scenes show that the satellite laser network presented by the paper can be fit for high-speed satellite communications. Such analysis can provide effective reference for the research of satellite laser networking and communication protocol.

  16. Defenses against Covert-Communications in Multimedia and Sensor Networks 

    E-print Network

    Jainsky, Julien Sebastien 1981-

    2012-11-29

    but underdeveloped domains. Indeed, this work focuses on the novel problem of visual sensor network steganalysis but also proposes one of the first solutions against video steganography. The first part of the dissertation looks at covert-communications in videos...

  17. A cooperative communication protocol for wireless ad-hoc networks

    E-print Network

    Silber, Jeremy I. (Jeremy Isaac), 1980-

    2002-01-01

    This thesis presents the design and implementation of a communication protocol that utilizes local cooperation among nodes to efficiently transfer data. Multi-hop routing in ad-hoc wireless networks realizes some scalability ...

  18. Poster Abstract: Modular Communication Protocols for Sensor Networks

    E-print Network

    do not propose a modular scheduler or memory management. The remainder is structured as followsPoster Abstract: Modular Communication Protocols for Sensor Networks Olaf Landsiedel Jó Ágila Bitsch Katharina Denkinger Klaus Wehrle Protocol Engineering and Distributed Systems Group University

  19. Scaling behaviors in the communication network between cities

    E-print Network

    Ratti, Carlo

    Researchers have been unable to predict the large-scale features of aggregate social networks. We analyze the anonymous communications patterns of 2.5 million customers of a Belgian mobile phone operator. With these ...

  20. Hindawi Publishing Corporation EURASIP Journal on Wireless Communications and Networking

    E-print Network

    Rontogiannis, Athanasios A.

    Hindawi Publishing Corporation EURASIP Journal on Wireless Communications and Networking Volume detection. The wireless channel can be characterized either by the conventional tapped-delay line (TDL interference and multipath fading, joint multiuser detection and parametric channel estimation ap- proaches

  1. Robust Communications for Sensor Networks in Hostile Environments

    E-print Network

    Fahmy, Sonia

    Robust Communications for Sensor Networks in Hostile Environments Ossama Younis and Sonia Fahmy--2066, USA E­mail: {oyounis,fahmy}@cs.purdue.edu Paolo Santi Instituto di Informatica e Telematica, CNR Via G

  2. Robust Communications for Sensor Networks in Hostile Environments

    E-print Network

    Fahmy, Sonia

    Robust Communications for Sensor Networks in Hostile Environments Ossama Younis and Sonia Fahmy­2066, USA E-mail: {oyounis,fahmy}@cs.purdue.edu Paolo Santi Instituto di Informatica e Telematica, CNR Via G

  3. Computational Inference of Neural Information Flow Networks

    E-print Network

    Jarvis, Erich D.

    Computational Inference of Neural Information Flow Networks V. Anne Smith1[¤ , Jing Yu1,2[¤ , Tom V successful at inferring nonlinear neural information flow networks from electrophysiology data collected data incorrectly produces networks with information flow to non-neural tissue and over paths known

  4. Fiber-Optic Terahertz Data-Communication Networks

    NASA Technical Reports Server (NTRS)

    Chua, Peter L.; Lambert, James L.; Morookian, John M.; Bergman, Larry A.

    1994-01-01

    Network protocols implemented in optical domain. Fiber-optic data-communication networks utilize fully available bandwidth of single-mode optical fibers. Two key features of method: use of subpicosecond laser pulses as carrier signals and spectral phase modulation of pulses for optical implementation of code-division multiple access as multiplexing network protocol. Local-area network designed according to concept offers full crossbar functionality, security of data in transit through network, and capacity about 100 times that of typical fiber-optic local-area network in current use.

  5. Randomized parallel communications on an extension of the omega network

    Microsoft Academic Search

    Debasis Mitra; Randall A. Cieslak

    1987-01-01

    Parallel communication algorithms and networks are central to large-scale parallel computing and, also, data communications. This paper identifies adverse source-destination traffic patterns and proposes a scheme for obtaining relief by means of randomized routing of packets on simple extensions of the well-known omega networks. Valiant and Aleliunas have demonstrated randomized algorithms, for a certain context which we call nonrenewal, that

  6. Using Delay Tolerant Networks for Car2Car communications

    Microsoft Academic Search

    Laurent Franck; Felipe Gil-Castineira

    2007-01-01

    In this paper we identify and discuss the main issues and challenges to implement a Delay Tolerant Network (DTN) to allow multi-hop Car2Car (C2C) -also known as Vehicle2Vehicle (V2V)- and car2infrastructure (C2I) communications. C2C communications are designed to increase automobile security and comfort, but a single hop is not enough [1]. Efficient network layers are necessary to overcome these limitations.

  7. Transparent self-healing communication networks via diversity coding

    Microsoft Academic Search

    Chih-Lin I; Ender Ayanoglu; R. D. Gitlin; J. E. Mazo

    1990-01-01

    The authors present an error control based approach, called diversity coding, to provide nearly instantaneous self-healing digital communication networks. This is achieved by constructing an error-correcting code across logically independent channels and by treating link failures within the framework of an erasure channel model. Diversity coding is more efficient than the existing approaches to self-healing communication networks since it is

  8. Family Health History Communication Networks of Older Adults: Importance of Social Relationships and Disease Perceptions

    ERIC Educational Resources Information Center

    Ashida, Sato; Kaphingst, Kimberly A.; Goodman, Melody; Schafer, Ellen J.

    2013-01-01

    Older individuals play a critical role in disseminating family health history (FHH) information that can facilitate disease prevention among younger family members. This study evaluated the characteristics of older adults and their familial networks associated with two types of communication ("have shared" and "intend to share…

  9. PUBLISHED IN: COMMUNICATIONS SURVEYS AND TUTORIALS, VOL. 16, NO. 2, 2014, PP. 10241049 1 A Survey of Information-Centric Networking

    E-print Network

    Chatziantoniou, Damianos

    requirement from the Internet at that time was merely that of forwarding packets of data among a limited Internet architecture was founded upon a host-centric communication model, which was appropriate for coping with the needs of the early Internet users. Internet usage has evolved however, with most users mainly interested

  10. A Professional Development Project for Improving the Use of Information and Communication Technologies in Science Teaching

    ERIC Educational Resources Information Center

    Lavonen, Jari; Juuti, Kalle; Aksela, Maija; Meisalo, Veijo

    2006-01-01

    This article describes a professional development project aiming to develop practical approaches for the integration of information and communication technologies (ICT) into science education. Altogether, 13 two-day face-to-face seminars and numerous computer network conferences were held during a three-year period. The goals for the project were…

  11. The Internet, Political Communications Research and the Search for a New Information Paradigm

    ERIC Educational Resources Information Center

    Chiu, William Franklin

    2013-01-01

    The Internet, as a digital record of human discourse, provides an opportunity to directly analyze political communicative behavior. The rapid emergence of social online networks augurs a transformation in the quality and quantity of information people have to evaluate their political system. Digital formats instantiate new categories of actors and…

  12. Challenges of Information and Communication Technology in Energy Efficient Smart Homes

    Microsoft Academic Search

    Dragan Markovic; Dragan Cvetkovic; Dejan Zivkovic; Ranko Popovic

    2012-01-01

    Energy saving is an important issue in the times of increasing energy prices. Products and services provided by the information and communication technology (ICT) can support energy efficiency and emissions reductions. The synergy of ICT and a residential area gives rise to the smart home environment. Ecological and smart home network applications should not only improve the peoples life satisfaction

  13. Junior / Community College Students with Learning Disabilities and Their Use of Information and Communication Technologies (ICTs)

    ERIC Educational Resources Information Center

    Nguyen, Mai Nhu; Fichten, Catherine; King, Laura; Barile, Maria; Mimouni, Zohra; Havel, Alice; Raymond, Odette; Juhel, Jean-Charles; Jorgensen, Shirley; Chauvin, Alexandre; Gutberg, Jennifer; Budd, Jillian; Hewlett, Maureen; Heiman, Tali; Gaulin, Chris; Asuncion, Jennison

    2013-01-01

    Junior / community college students who have learning disabilities (LD), such as dyslexia, often do not maximize their use of information and communication technologies (ICTs) for school work. They do not use many of these technologies nor do they know as much about them as other students. These are the results of an Adaptech Research Network

  14. The Implications of Information and Communications Technologies for Distance Education: Looking toward the Future. Final Report

    ERIC Educational Resources Information Center

    Arafeh, Sousan

    2004-01-01

    One salient factor of increasing interest in distance education is advancement in information and communications technologies (ICTs). In particular, digital and networked technologies have had a wide range of effects on the educational materials, practices, and institutions involved in education, notably by improving time-and cost-efficient…

  15. Adaptive protocols for information dissemination in wireless sensor networks

    Microsoft Academic Search

    Wendi Rabiner Heinzelman; Joanna Kulik; Hari Balakrishnan

    1999-01-01

    In this paper, we present a family of adaptive protocols, called SPIN (Sensor Protocols for Information via Negotia- tion), that efficiently disseminates information among sen- sors in an energy-constrained wireless sensor network. Nodes running a SPIN communication protocol name their data us- ing high-level data descriptors, called meta-data. They use meta-data negotiations to eliminate the transmission of re- dundant data

  16. Deep Space Network information system architecture study

    NASA Technical Reports Server (NTRS)

    Beswick, C. A.; Markley, R. W. (editor); Atkinson, D. J.; Cooper, L. P.; Tausworthe, R. C.; Masline, R. C.; Jenkins, J. S.; Crowe, R. A.; Thomas, J. L.; Stoloff, M. J.

    1992-01-01

    The purpose of this article is to describe an architecture for the Deep Space Network (DSN) information system in the years 2000-2010 and to provide guidelines for its evolution during the 1990s. The study scope is defined to be from the front-end areas at the antennas to the end users (spacecraft teams, principal investigators, archival storage systems, and non-NASA partners). The architectural vision provides guidance for major DSN implementation efforts during the next decade. A strong motivation for the study is an expected dramatic improvement in information-systems technologies, such as the following: computer processing, automation technology (including knowledge-based systems), networking and data transport, software and hardware engineering, and human-interface technology. The proposed Ground Information System has the following major features: unified architecture from the front-end area to the end user; open-systems standards to achieve interoperability; DSN production of level 0 data; delivery of level 0 data from the Deep Space Communications Complex, if desired; dedicated telemetry processors for each receiver; security against unauthorized access and errors; and highly automated monitor and control.

  17. Deep Space Network information system architecture study

    NASA Astrophysics Data System (ADS)

    Beswick, C. A.; Markley, R. W.; Atkinson, D. J.; Cooper, L. P.; Tausworthe, R. C.; Masline, R. C.; Jenkins, J. S.; Crowe, R. A.; Thomas, J. L.; Stoloff, M. J.

    1992-05-01

    The purpose of this article is to describe an architecture for the Deep Space Network (DSN) information system in the years 2000-2010 and to provide guidelines for its evolution during the 1990s. The study scope is defined to be from the front-end areas at the antennas to the end users (spacecraft teams, principal investigators, archival storage systems, and non-NASA partners). The architectural vision provides guidance for major DSN implementation efforts during the next decade. A strong motivation for the study is an expected dramatic improvement in information-systems technologies, such as the following: computer processing, automation technology (including knowledge-based systems), networking and data transport, software and hardware engineering, and human-interface technology. The proposed Ground Information System has the following major features: unified architecture from the front-end area to the end user; open-systems standards to achieve interoperability; DSN production of level 0 data; delivery of level 0 data from the Deep Space Communications Complex, if desired; dedicated telemetry processors for each receiver; security against unauthorized access and errors; and highly automated monitor and control.

  18. A Mesochronous Technique for Communication in Network on Chips

    Microsoft Academic Search

    M. Saneei; A. Afzali-Kusha; Z. Navabi

    2006-01-01

    In this paper, we propose a mesochronous scheme for communication over serial buses in network on chips (NoC). The technique, which removes metastability errors in mesochronous communications, makes use of only one strobe line with the bus. The strobe line toggles once with every frame of the data. In the suggested method, the frequencies of the transmitter and the receiver

  19. Overview of channel models for underwater wireless communication networks

    Microsoft Academic Search

    Mari Carmen Domingo

    2008-01-01

    Acoustic communication in Underwater Wireless Communication Networks (UWCNs) has several challenges due to the presence of fading, multipath and refractive properties of the sound channel which necessitate the development of precise underwater channel models. Some existing channel models are simplified and do not consider multipath or multipath fading. In this paper, a detailed survey on ray-theory-based multipath Rayleigh underwater channel

  20. Interference suppression in wireless digital video communication networks

    Microsoft Academic Search

    Branka Zovko-Cihlar; Branka Medved Rogina; Sonja Grgic

    2004-01-01

    This paper describes the interference suppression in wireless digital video communication networks. Wireless digital systems are significantly less sensitive to noise and interference. The frequency spectrum is used to introduce wireless digital video services. Wireless digital video systems may offer improved RF performance, can work in communication conditions where spectrum efficiency is not to high and sophisticated modulation and error

  1. A Power Line Communication Network Infrastructure for The Smart Home

    E-print Network

    Latchman, Haniph A.

    A Power Line Communication Network Infrastructure for The Smart Home Yu-Ju Lin, Haniph A. Latchman's as a basic infrastructure for building integrated "smart homes," wherein infor- mation appliances (IA guarantee QoS for real-time communications, supporting delay sensitive data streams for "Smart Home

  2. Accent: A Communication Oriented Network Operating System Kernel

    Microsoft Academic Search

    Richard F. Rashid; George G. Robertson

    1981-01-01

    Accent is a communication oriented operating system kernel being built at Carnegie-Mellon University to support the distributed personal computing project, Spice, and the development of a fault-tolerant distributed sensor network (DSN). Accent is. built around a single, powerful abstraction of communication between processes, with all kernel functions, such as device access and virtual memory management accessible through messages and distributable

  3. Performance of an industrial data communication protocol on ethernet network

    Microsoft Academic Search

    Endra Joelianto; Hosana

    2008-01-01

    One of the well known industrial data communication protocols is Modbus which is widely used in industrial automation due to its availability. Modbus protocol can be implemented in many ways according to its network. Performance metrics and tests for IT infrastructure equipment have been used for many years, but now with real-time communication being used more, users are asking whether

  4. Teaching Data Communications Using Cisco Networking Academy's Curriculum

    Microsoft Academic Search

    J. Art Gowan

    A program that should be considered closely when looking at curriculum for teaching a course in data communications is Cisco's Networking Academy Program. The curriculum is entirely online, web-based, with substantial online support features for both faculty and students. The content of the first semester is basic data communications theory. The content of the subsequent semesters is more Cisco specific.

  5. On Secure and Resilient Telesurgery Communications over Unreliable Networks

    E-print Network

    Wang, Yongge

    , adhering some maxi- mum tolerable delay, and providing various security measures depending on the natureOn Secure and Resilient Telesurgery Communications over Unreliable Networks M. Engin Tozal+, Yongge of a se- cure and reliable wireless communication conforming to the application tolerable delay for TRSs

  6. Anonymous Communications he ubiquity of networked computers has made

    E-print Network

    Anonymous Communications T he ubiquity of networked computers has made increasing amounts of user, thenanonymityofcommunicationisitsbedrock--with- out anonymous communication, cryptography-based privacy would be very weak indeed. Every message has two anonymity sets--groups of identities assigned to the message's sender or receiver to help

  7. Statistical Modeling of Asynchronous Impulsive Noise in Powerline Communication Networks

    Microsoft Academic Search

    Marcel Nassar; Kapil Gulati; Yousof Mortazavi; Brian L. Evans

    2011-01-01

    Powerline distribution networks are increasingly being employed to support smart grid communication infrastructure and in-home LAN connectivity. However, their primary function of power distribution results in a hostile environment for communication systems. In particular, asynchronous impulsive noise, with levels as high as 50dB above thermal noise, causes significant degradation in communication performance. Much of the prior work uses limited empirical

  8. Long Distance Wireless Disaster Information Network by Automatic Directional Antenna Control Method

    Microsoft Academic Search

    Daisuke Asahizawa; Goshi Sato; Toshihiro Suzuki; Yoshitaka Shibata

    2010-01-01

    It is proved that wireless network is suitable for disaster information infrastructure because of its robustness, mobility and flexibility. However current conventional wireless networks have limit in communication distance because of low electro-magnetic power density, non-directional antenna. This is quite fatal as emergency network particularly in mountain areas like Japan. In order to solve those problems, in this paper, we

  9. Sensor network and information interoperability integrating IEEE 1451 with MIMOSA and OSA-CBM

    Microsoft Academic Search

    Kang Lee; Robert X. Gao; Rick Schneeman

    2002-01-01

    The IEEE 1451 smart transducer interface for sensors and actuators standard was developed to facilitate sensor to network interoperability. It has defined a set of common communication interfaces for connecting transducers (sensors or actuators) to control networks and instruments in a network-independent environment. Concurrently, the Machinery Information Management Open Systems Alliance (MIMOSA) has established an open architecture and a set

  10. Software design of optical link for indoor wireless optical communication network used LEDs as source visible light communication

    NASA Astrophysics Data System (ADS)

    Liner, Andrej; Papes, Martin; Jaros, Jakub; Koudelka, Petr; Latal, Jan; Vitasek, Jan; Hajek, Lukas; Vasinek, Vladimir

    2015-01-01

    Nowadays, the conventional light sources are replaced progressively evolving LED (Light Emitting Diode) for their deficient properties. This technology recorded dynamic growth mainly due to effective research in increasing power density and choice the color shade on good color rendering CRI (Color Rendering Index). This extending the zone of used LEDs. Development of lighting technology by means of white power LEDs provided impulse to the idea of the development of optical wireless data networks based on optical radiation in the visible region of the spectrum VLC (Visible Light Communications). In the last years being recorded a turnover of research from transmission of information via optical fiber to the transmission of information through wireless networks. At the same time the concept of information transmission by indirect sight between transmitter and receiver NLOS (Non Line of Sight) is changing. Line of research focuses mainly on the direct line of sight LOS (Line of Sight). This is due to the development of the semiconductor lighting through the white power LED. This is connected with the idea of using them as a transmitter for communication purposes. This article deals with software design of optical link for indoor wireless optical network in LightTools software. Optimal optical source was designed for communication using LED as the first. For the proposed type of LEDs sources were used different shapes and distances distribution between LEDs in a single cell at the designed optical transmitter.

  11. 75 FR 63473 - Notice of Public Information Collection(s) Being Reviewed by the Federal Communications...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-15

    ...communications in the Nation's communications networks and critical...disruptions reporting from all communications providers (cable, satellite, wireline and wireless...voice and/or paging communications. As envisioned,...

  12. A weighted communicability measure applied to complex brain networks

    PubMed Central

    Crofts, Jonathan J.; Higham, Desmond J.

    2009-01-01

    Recent advances in experimental neuroscience allow non-invasive studies of the white matter tracts in the human central nervous system, thus making available cutting-edge brain anatomical data describing these global connectivity patterns. Through magnetic resonance imaging, this non-invasive technique is able to infer a snapshot of the cortical network within the living human brain. Here, we report on the initial success of a new weighted network communicability measure in distinguishing local and global differences between diseased patients and controls. This approach builds on recent advances in network science, where an underlying connectivity structure is used as a means to measure the ease with which information can flow between nodes. One advantage of our method is that it deals directly with the real-valued connectivity data, thereby avoiding the need to discretize the corresponding adjacency matrix, i.e. to round weights up to 1 or down to 0, depending upon some threshold value. Experimental results indicate that the new approach is able to extract biologically relevant features that are not immediately apparent from the raw connectivity data. PMID:19141429

  13. Computers and Communication Networks in Educational Settings in the Twenty-First Century: Preparation for Educators' New Roles.

    ERIC Educational Resources Information Center

    Kook, Joong-Kak

    1997-01-01

    Discussion of changes in classrooms as a result of communication networks focuses on teachers' roles in future educational settings. Topics include teachers as information consultants, as team collaborators, as facilitators, as course developers, and as academic advisors; and the computer and communication skills needed by teachers. (LRW)

  14. Network analysis of team communication in a busy emergency department

    PubMed Central

    2013-01-01

    Background The Emergency Department (ED) is consistently described as a high-risk environment for patients and clinicians that demands colleagues quickly work together as a cohesive group. Communication between nurses, physicians, and other ED clinicians is complex and difficult to track. A clear understanding of communications in the ED is lacking, which has a potentially negative impact on the design and effectiveness of interventions to improve communications. We sought to use Social Network Analysis (SNA) to characterize communication between clinicians in the ED. Methods Over three-months, we surveyed to solicit the communication relationships between clinicians at one urban academic ED across all shifts. We abstracted survey responses into matrices, calculated three standard SNA measures (network density, network centralization, and in-degree centrality), and presented findings stratified by night/day shift and over time. Results We received surveys from 82% of eligible participants and identified wide variation in the magnitude of communication cohesion (density) and concentration of communication between clinicians (centralization) by day/night shift and over time. We also identified variation in in-degree centrality (a measure of power/influence) by day/night shift and over time. Conclusions We show that SNA measurement techniques provide a comprehensive view of ED communication patterns. Our use of SNA revealed that frequency of communication as a measure of interdependencies between ED clinicians varies by day/night shift and over time. PMID:23521890

  15. Synchronization and a secure communication scheme using optical star network

    NASA Astrophysics Data System (ADS)

    Jeeva Sathya Theesar, S.; Ariffin, M. R. K.; Banerjee, Santo

    2013-12-01

    This work aims to show the effect of synchronization phenomena in multi-nodal star optical network topology as well as to develop an efficient symmetric cryptosystem utilizing available parameters. The optical network is based on chaotic semiconductor laser (SL) systems described by dimensionless modified Lang-Kobayashi's (L-K) delay differential equations. The network nodes are mutually connected with a central semiconductor laser hub with bidirectional linear optical feedback. It has been observed that the laser output can be modulated using a star network setup. The laser intensity increases with the number of nodes and its much more higher than the same for solitary laser, keeping all other inputs as constant. So the network topology is an effective way to optimize the output power. The process by each nodes into the network is illustrated graphically for three, five and seven SLs, respectively. Also the whole network can be implemented as an optical communication system for transmission of signals. Each SL can act as a transceiver during communication. The communication process is examined using a chaotic signal as a plaintext connected with the SL hub and successfully provided a symmetrically secure mechanism upon the communication protocol. The result shows the optimization of output power with the increment of the number of nodes. Also the communication scheme can successfully decode the encrypted signal from SL Hub, at each other nodes.

  16. Operations of the reconfigured Ground Communications Facility Central Communications Terminal and the Network Operations Control Center

    NASA Technical Reports Server (NTRS)

    Santana, J. C.; Jennings, L. E.

    1982-01-01

    The ground communications facility (GCF) central communications terminal and network operations control center (NOCC) hardware was rearranged, supplemented, and modified, and software programs changed to provide an improved GCF and NOCC operational environment and capability. Control center operations section activities required to make the changeover from the old to the new GCF and NOCC configuration are addressed.

  17. Mothers' use of information and communication technologies for information seeking.

    PubMed

    Jang, Juyoung; Dworkin, Jodi; Hessel, Heather

    2015-04-01

    Previous studies have revealed that information and communication technologies (ICTs) play a crucial role in parenting. Utilizing a national sample of mothers, the current study addresses mothers' information-seeking behaviors using ICTs utilizing the sense-making theoretical approach. Specifically, the study explored mothers' gap-bridging activities via online information venues including blogs, discussion boards/chatrooms, e-mailed newsletters, and online courses. Further, the associations were examined between mothers' demographic characteristics and their patterns of gap-bridging activities using online information venues. Latent class analysis revealed five latent classes: limited gap bridging, active gap bridging, problem identifiers, perspective explorers, and reassurance seekers. The "limited gap bridging" latent class was the most common class across online information venues. The other latent classes illustrate a more complex picture of mothers' gap-bridging activities depending on their needs. Mothers' demographic characteristics were associated with their patterns of gap-bridging activities. Implications of these findings for future research are discussed. PMID:25803204

  18. Functional communication within a perceptual network processing letters and pseudoletters.

    PubMed

    Herdman, Anthony T

    2011-10-01

    Many studies have identified regions within human ventral visual stream to be important for object identification and categorization; however, knowledge of how perceptual information is communicated within the visual network is still limited. Current theories posit that if a high correspondence between incoming sensory information and internal representations exists, then the object is rapidly identified, and if there is not, then the object requires extra detailed processing. Event-related responses from the present magnetoencephalography study showed two main effects. The N1m peak latencies were approximately 15 milliseconds earlier to familiar letters than to unfamiliar pseudoletters, and the N2m was more negative to pseudoletters than to letters. Event-related beamforming analyses identified these effects to be within bilateral visual cortices with a right lateralization for the N2m effect. Furthermore, functional connectivity analyses revealed that gamma-band (50-80 Hz) oscillatory phase synchronizations among occipital regions were greater to letters than to pseudoletters (around 85 milliseconds). However, during a later time interval between 245 and 375 milliseconds, pseudoletters elicited greater gamma-band phase synchronizations among a more distributed occipital network than did letters. These findings indicate that familiar object processing begins by at least 85 milliseconds, which could represent an initial match to an internal template. In addition, unfamiliar object processing persisted longer than that for familiar objects, which could reflect greater attention to inexperienced objects to determine their identity and/or to consolidate a new template to aid in future identification. PMID:21946359

  19. 10 CFR 75.12 - Communication of information to IAEA.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Section 75.12 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) SAFEGUARDS ON NUCLEAR MATERIAL-IMPLEMENTATION OF US/IAEA AGREEMENT Facility and Location Information § 75.12 Communication of information to IAEA. (a) Except...

  20. Dynamics of rumor-like information dissemination in complex networks

    NASA Astrophysics Data System (ADS)

    Nekovee, Maziar; Moreno, Yamir; Bianconi, Ginestra

    2005-03-01

    An important dynamic process that takes place in complex networks is the spreading of information via rumor-like mechanisms. In addition to their relevance to propagation of rumors and fads in human society, such mechanism are also the basis of an important class of collective communication protocols in complex computer networks, such as the Internet and the peer-to-peer systems. In this talk we present results of our analytical, numerical and large-scale Monte Carlo simulation studies of this process on several classes of complex networks, including random graphs, scale-free networks, and random and small-world topological graphs. Our studies point out to important differences between the dynamics of rumor spreading and that of virus spreading in such networks, and provide new insights into the complex interplay between the spreading phenomena and network topology.

  1. Health care network communications infrastructure: an engineering design for the Military Health Service System.

    PubMed

    Hoffman, P; Kline, E; George, L; Price, K; Clark, M; Walasin, R

    1995-01-01

    The Military Health Service System (MHSS) provides health care for the Department of Defense (DOD). This system operates on an annual budget of $15 Billion, supports 127 medical treatment facilities (MTFs) and 500 clinics, and provides support to 8.7 million beneficiaries worldwide. To support these facilities and their patients, the MHSS uses more than 125 different networked automated medical systems. These systems rely on a heterogeneous telecommunications infrastructure for data communications. With the support of the Defense Medical Information Management (DMIM) Program Office, our goal was to identify the network requirements for DMIM migration and target systems and design a communications infrastructure to support all systems with an integrated network. This work used tools from Business Process Reengineering (BPR) and applied it to communications infrastructure design for the first time. The methodology and results are applicable to any health care enterprise, military or civilian. PMID:8563346

  2. Communication and information: alternative uses of the Internet in households

    Microsoft Academic Search

    Robert E. Kraut; Tridas Mukhopadhyay; Janusz Szczypula; Sara B. Kiesler; William L. Scherlis

    1998-01-01

    The Internet has been characterized as a superhighway to information and as a high-tech extension of the home telephone. How are people really using the Internet? The history of previous technologies that support interpersonal communication suggests that communication may be a more important use and determinant of participants’ commitment to the Internet than is information acquisition and entertainment. Operationalizing interpersonal

  3. Fading Channels: Information-Theoretic and Communication Aspects

    Microsoft Academic Search

    Ezio Biglieri; John G. Proakis; Shlomo Shamai

    1998-01-01

    In this paper we review the most peculiar and interesting information-theoretic and communications features of fading channels. We first describe the statistical models of fading channels which are frequently used in the analysis and design of communication systems. Next, we focus on the information theory of fading channels, by emphasizing capacity as the most important performance measure. Both single-user and

  4. Fading channels: information-theoretic and communications aspects

    Microsoft Academic Search

    Ezio Biglieri; John Proakis; Shlomo Shamai

    1998-01-01

    In this paper we review the most peculiar and interesting information-theoretic and communications features of fading channels. We first describe the statistical models of fading channels which are frequently used in the analysis and design of communication systems. Next, we focus on the information theory of fading channels, by emphasizing capacity as the most important performance measure. Both single-user and

  5. The synergism of teleworking and information and communication technologies

    Microsoft Academic Search

    Manuela Pérez Pérez; Angel Martínez Sánchez; Pilar de Luis Carnicer; María José Vela Jiménez

    2005-01-01

    Purpose – Aims to contribute to the teleworking literature by analysing the differences between teleworking adopters and non-adopters regarding the use and impact of information and communication technologies. Design\\/methodology\\/aproach – Analyses the differences on the use and impact of information and communication technologies in a sample of Spanish companies. The data for the study come from a survey of a

  6. Computing, Information, and Communications Technology (CICT) Program Overview

    NASA Technical Reports Server (NTRS)

    VanDalsem, William R.

    2003-01-01

    The Computing, Information and Communications Technology (CICT) Program's goal is to enable NASA's Scientific Research, Space Exploration, and Aerospace Technology Missions with greater mission assurance, for less cost, with increased science return through the development and use of advanced computing, information and communication technologies

  7. An Information Statistics Approach to Data Stream and Communication Complexity

    Microsoft Academic Search

    Ziv Bar-yossef; T. S. Jayram; Ravi Kumar; D. Sivakumar

    2002-01-01

    We present a new method for proving strong lower bounds in communication com- plexity. This method is based on the notion of the conditional information complexity of a function which is the minimum amount of information about the inputs that has to be revealed by a communication protocol for the function. While conditional infor- mation complexity is a lower bound

  8. Information and Communications Technologies Center (ICT) YouTube Channel

    NSDL National Science Digital Library

    This page presents the YouTube channel of the National Center for Information and Communications Technologies (ICT Center). There is a growing collection of videos - focusing on information and communication technologies - on topics such as Second Life, the oscilloscope, digital media production, games and gaming, as well as a number of interviews with others in the telecommunications technology field.

  9. Communicating Disclosure Risk in Informed Consent Statements

    PubMed Central

    Singer, Eleanor; Couper, Mick P.

    2011-01-01

    For several years, we have experimented with various ways of communicating disclosure risk and harm to respondents in order to determine how these affect their willingness to participate in surveys. These experiments, which used vignettes administered to an online panel as well as a mail survey sent to a national probability sample, have demonstrated that (a) the probability of disclosure alone has no apparent effect on people's willingness to participate in the survey described, (b) the sensitivity of the survey topic has such an effect, and (c) making explicit the possible harms that might result from disclosure also reduces willingness to participate, in both the vignette and the mail experiments. As a last study in this series, we experimented with different ways of describing disclosure risk in informed consent statements that might more plausibly be used in real surveys, again using vignettes administered to an online panel. As suggested by our earlier work, we found that the precise wording of the confidentiality assurance had little effect on respondents' stated willingness to participate in the hypothetical survey described. However, the experimental manipulations did have some effect on perceptions of the risks and benefits of participation, suggesting that they are processed by respondents. And, as we have found in our previous studies, the topic of the survey has a consistent and statistically significant effect on stated willingness to participate. We explore some implications of these findings for researchers seeking to provide adequate information to potential survey respondents without alarming them unnecessarily. PMID:20831416

  10. Traffic improvements in wireless communication networks using antenna arrays

    Microsoft Academic Search

    Javad Razavilar; Farrokh Rashid-Farrokhi; K. J. Ray Liu

    2000-01-01

    A wireless network with beamforming capabilities at the receiver is considered that allows two or more transmitters to share the same channel to communicate with the base station. A novel approach is introduced, which combines the effects of the digital signal processing (adaptive beamforming) at the physical layer with the traffic policies at the network layer on the overall queuing

  11. Toward a Communications Satellite Network for Humanitarian Relief

    NASA Technical Reports Server (NTRS)

    Burleigh, Scott C.; Birrane, Edward J.

    2011-01-01

    Since the introduction in 2008 of the "Ring Road" concept, proposing a communications satellite network designed to support disadvantaged populations, there have been a number of advances in the underlying technologies, CubeSat picosatellites and Delay-Tolerant Networking. We review the original Ring Road proposal, discuss relevant recent technological progress, and offer some tentative notes on projected cost and performance.

  12. MEASUREMENT-BASED USAGE CHARGES IN COMMUNICATIONS NETWORKS

    E-print Network

    Weber, Richard

    to exercise control. The congestion that has plagued the Internet because it lacks any mechanism for charging and pricing highlights the fact that without charges it is di cult to control congestion or divide networkMEASUREMENT-BASED USAGE CHARGES IN COMMUNICATIONS NETWORKS COSTAS COURCOUBETIS ICS

  13. Complex Dynamics in Communication Networks Data Traffic, Topology and Congestion

    E-print Network

    Arrowsmith, David

    - Complex Dynamics in Communication Networks Data Traffic, Topology and Congestion D.K. Arrowsmith1 delay time. Previously, the statistical properties of packet traffic, which are dependent on the control the behaviour of packet traffic flowing on realistic networks as load is varied. The use of intermittency

  14. Communications network design and costing model programmers manual

    NASA Technical Reports Server (NTRS)

    Logan, K. P.; Somes, S. S.; Clark, C. A.

    1983-01-01

    Otpimization algorithms and techniques used in the communications network design and costing model for least cost route and least cost network problems are examined from the programmer's point of view. All system program modules, the data structures within the model, and the files which make up the data base are described.

  15. Preliminary Evaluation, Texas State Library Communication Network, 1968.

    ERIC Educational Resources Information Center

    Texas State Library, Austin. Field Services Div.

    In 1968 the Texas State Library established a library communications network under Title III of the Librar y Services and Construction Act. The objective of this study was to evaluate the network after six months of operation. Part I of the study consists of a general evaluation by Peat, Marwick, Mitchell and Co., based on operational data…

  16. Communications performance of an undersea acoustic large-area network

    Microsoft Academic Search

    Hannah A. Kriewaldt; Joseph A. Rice

    2005-01-01

    The U.S. Navy is developing Seaweb acoustic networking capability for integrating undersea systems. Seaweb architectures generally involve a wide-area network of fixed nodes consistent with future distributed autonomous sensors on the seafloor. Mobile nodes including autonomous undersea vehicles (AUVs) and submarines operate in the context of the grid by using the fixed nodes as both navigation reference points and communication

  17. Energy-Efficient Communication in Multi-interface Wireless Networks

    Microsoft Academic Search

    Stavros Athanassopoulos; Ioannis Caragiannis; Christos Kaklamanis; Evi Papaioannou

    2009-01-01

    We study communication problems in wireless networks sup- porting multiple interfaces. In such networks, two nodes can communi- cate if they are close and share a common interface. The activation of each interface has a cost reflecting the energy consumed when a node uses this interface. We distinguish between the symmetric and non-symmetric case, depending on whether all nodes have

  18. Military secure communications over public cellular network infrastructure

    Microsoft Academic Search

    Roberto Di Pietro; Gianluigi Me

    2002-01-01

    The availability of a tactical communication channel that could be everywhere accessible possibly via wireless devices and provide an adequate bandwidth is a constant matter for both military and law enforcement agencies. In particular, the public cellular network infrastructure can provide with such features. However, while conducting military operations, resorting to such a network is not a viable solution, usually,for

  19. ESC: Energy Synchronized Communication in Sustainable Sensor Networks

    E-print Network

    Massachusetts at Amherst, University of

    Abstract--With advances in energy harvesting techniques, it is now feasible to build sustainable sensorESC: Energy Synchronized Communication in Sustainable Sensor Networks Yu Gu, Ting Zhu and Tian He of sustainable sensor networks is to effectively utilize a continuous stream of ambient energy. Instead

  20. Route Optimization for Intra Communication of a Nested Mobile Network

    E-print Network

    National University hscho@mmlab.snu.ac.kr ABSTRACT Network mobility, i.e. Internet access services.11/16) and mobile communication services, the demand for Internet access in mobile vehicles such as trains, buses is referred to as network mobility (NEMO) support. To address the NEMO support problem, Internet Engineering

  1. A secure network to connect (mobile) devices for interpersonal communication

    E-print Network

    Biagioni, Edoardo S.

    AllNet A secure network to connect (mobile) devices for interpersonal communication without Very little resources needed for text 140 characters for twitter, SMS A p2p network can support not secure PGP more effective if key exchange is improved Mobile devices in range of each other can

  2. PREFACE: Quantum Information, Communication, Computation and Cryptography

    NASA Astrophysics Data System (ADS)

    Benatti, F.; Fannes, M.; Floreanini, R.; Petritis, D.

    2007-07-01

    The application of quantum mechanics to information related fields such as communication, computation and cryptography is a fast growing line of research that has been witnessing an outburst of theoretical and experimental results, with possible practical applications. On the one hand, quantum cryptography with its impact on secrecy of transmission is having its first important actual implementations; on the other hand, the recent advances in quantum optics, ion trapping, BEC manipulation, spin and quantum dot technologies allow us to put to direct test a great deal of theoretical ideas and results. These achievements have stimulated a reborn interest in various aspects of quantum mechanics, creating a unique interplay between physics, both theoretical and experimental, mathematics, information theory and computer science. In view of all these developments, it appeared timely to organize a meeting where graduate students and young researchers could be exposed to the fundamentals of the theory, while senior experts could exchange their latest results. The activity was structured as a school followed by a workshop, and took place at The Abdus Salam International Center for Theoretical Physics (ICTP) and The International School for Advanced Studies (SISSA) in Trieste, Italy, from 12-23 June 2006. The meeting was part of the activity of the Joint European Master Curriculum Development Programme in Quantum Information, Communication, Cryptography and Computation, involving the Universities of Cergy-Pontoise (France), Chania (Greece), Leuven (Belgium), Rennes1 (France) and Trieste (Italy). This special issue of Journal of Physics A: Mathematical and Theoretical collects 22 contributions from well known experts who took part in the workshop. They summarize the present day status of the research in the manifold aspects of quantum information. The issue is opened by two review articles, the first by G Adesso and F Illuminati discussing entanglement in continuous variable systems, the second by T Prosen, discussing chaos and complexity in quantum systems. Both topics have theoretical as well as experimental relevance and are likely to witness a fast growing development in the near future. The remaining contributions present more specific and very recent results. They involve the study of the structure of quantum states and their estimation (B Baumgartner et al, C King et al, S Olivares et al, D Petz et al and W van Dam et al), of entanglement generation and its quantification (G Brida et al, F Ciccarello et al, G Costantini et al, O Romero-Isart et al, D Rossini et al, A Serafini et al and D Vitali et al), of randomness related effects on entanglement behaviour (I Akhalwaya et al, O Dahlsten et al and L Viola et al), and of abstract and applied aspects of quantum computation and communication (K Audenart, G M D'Ariano et al, N Datta et al, L C Kwek et al and M Nathanson et al). We would like to express our gratitude to the European Commission, the Abdus Salam ICTP, SISSA and Eurotech SpA (Amaro, Udine, Italy) for financial and/or logistic support. Special thanks also go to the workshop secretary Marina De Comelli, and the secretaries of the Department of Theoretical Physics, University of Trieste, Sabrina Gaspardis and Rosita Glavina for their precious help and assistance.

  3. Frankfurt Artificial Stock Market: a microscopic stock market model with heterogeneous interacting agents in small-world communication networks

    Microsoft Academic Search

    Oliver Hein; Michael Schwind; Markus Spiwoks

    2008-01-01

    We study the relationship between communication network topologies, namely the small-world networks introduced by Watts and\\u000a Strogatz, and the simulation results of an artificial stock market, here the Frankfurt Artificial Stock Market. Heterogeneous\\u000a interacting agents communicate their success and trading strategy to their nearest neighbors. A process of information diffusion\\u000a arises through the adaptive behavior of agents when encountering more

  4. Space-based Networking Technology Developments in the Interplanetary Network Directorate Information Technology Program

    NASA Technical Reports Server (NTRS)

    Clare, Loren; Clement, B.; Gao, J.; Hutcherson, J.; Jennings, E.

    2006-01-01

    Described recent development of communications protocols, services, and associated tools targeted to reduce risk, reduce cost and increase efficiency of IND infrastructure and supported mission operations. Space-based networking technologies developed were: a) Provide differentiated quality of service (QoS) that will give precedence to traffic that users have selected as having the greatest importance and/or time-criticality; b) Improve the total value of information to users through the use of QoS prioritization techniques; c) Increase operational flexibility and improve command-response turnaround; d) Enable new class of networked and collaborative science missions; e) Simplify applications interfaces to communications services; and f) Reduce risk and cost from a common object model and automated scheduling and communications protocols. Technologies are described in three general areas: communications scheduling, middleware, and protocols. Additionally developed simulation environment, which provides comprehensive, quantitative understanding of the technologies performance within overall, evolving architecture, as well as ability to refine & optimize specific components.

  5. Crossbar Switches For Optical Data-Communication Networks

    NASA Technical Reports Server (NTRS)

    Monacos, Steve P.

    1994-01-01

    Optoelectronic and electro-optical crossbar switches called "permutation engines" (PE's) developed to route packets of data through fiber-optic communication networks. Basic network concept described in "High-Speed Optical Wide-Area Data-Communication Network" (NPO-18983). Nonblocking operation achieved by decentralized switching and control scheme. Each packet routed up or down in each column of this 5-input/5-output permutation engine. Routing algorithm ensures each packet arrives at its designated output port without blocking any other packet that does not contend for same output port.

  6. Novel technology for enhanced security and trust in communication networks

    NASA Astrophysics Data System (ADS)

    Milovanov, Alexander; Bukshpun, Leonid; Pradhan, Ranjit; Jannson, Tomasz

    2011-06-01

    A novel technology that significantly enhances security and trust in wireless and wired communication networks has been developed. It is based on integration of a novel encryption mechanism and novel data packet structure with enhanced security tools. This novel data packet structure results in an unprecedented level of security and trust, while at the same time reducing power consumption and computing/communication overhead in networks. As a result, networks are provided with protection against intrusion, exploitation, and cyber attacks and posses self-building, self-awareness, self-configuring, self-healing, and self-protecting intelligence.

  7. Multimedia Communications over IP Networks 4-6 September 2000, University of Plymouth

    E-print Network

    Abu-Rgheff, Mosa Ali

    Multimedia Communications over IP Networks 4-6 September 2000, University of Plymouth (QGWR(QG 4HWZRUN1HWZRUN Mike Buckley Lucent Technologies Multimedia Communications over IP Networks #12;Multimedia Communications over IP Networks 4-6 September 2000, University of Plymouth #12;Multimedia Communications over IP

  8. Local repair mechaism for reliable multicast in Integrated Communication and Broadcast Networks with scalability

    Microsoft Academic Search

    Hideya Yoshiuchi; Jiping Lu; Satoshi Yoshizawa; Zhisheng Niu

    2010-01-01

    With the rapid growth of bandwidth requirement for mobile multimedia services, broadcast communication infrastructure is desired as one of the best solutions for avoiding communication congestion. Integrated Communication and Broadcast Network (ICBN), consisting of broadcast network and communication network, is one of the solutions. However, in reliable multicast service over ICBN, feedbacks from receivers cause feedback implosion problem. Also, because

  9. A repair mechanism for reliable multicast in Integrated Communication and Broadcast Networks

    Microsoft Academic Search

    Hideya Yoshiuchi; Jiping Lv; Satoshi Yoshizawa; Zhisheng Niu

    2009-01-01

    With the rapid growth of bandwidth requirement for mobile multimedia services, broadcast communication infrastructure is desired as one of the best solutions for avoiding communication congestion. Integrated communication and broadcast network (ICBN), consisting of broadcast network and communication network, is one of the solutions. However, in reliable multicast service over ICBN, feedbacks from receivers cause feedback implosion problem. Also, because

  10. Secure group communications for Delay-Tolerant Networks

    Microsoft Academic Search

    Paul T. Edelman; Michael J. Donahoo; David B. Sturgill

    2010-01-01

    The increased demand for mobile communication and use of mobile devices in high-latency, resource impoverished environments has spurred the development and growth of Delay-Tolerant Networks (DTN). DTNs aim to provide interoperability between a range of heterogeneous networks, operating under resource-constrained circumstances and traditional infrastructure networks such as the Internet. Because of the circumstances, DTNs possess some interesting characteristics that make

  11. FIFO networking: Punctual event-triggered communication

    Microsoft Academic Search

    Viktor Leijon

    2009-01-01

    It is desirable to be able to combine ease of implementation of a network with the ability to analyze the properties of the network. In order to address this we present a MAC protocol where the network acts as a FIFO, and examine the resulting properties of the network using both a theoretical study of the waiting times and a

  12. 78 FR 6102 - Information Collection(s) Being Reviewed by the Federal Communications Commission, Comments...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-01-29

    ...FEDERAL COMMUNICATIONS COMMISSION Information Collection(s) Being Reviewed by the Federal Communications Commission, Comments Requested AGENCY: Federal Communications Commission. ACTION: Notice;...

  13. 78 FR 36185 - Information Collection(s) Being Reviewed by the Federal Communications Commission, Comments...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-17

    ...FEDERAL COMMUNICATIONS COMMISSION Information Collection(s) Being Reviewed by the Federal Communications Commission, Comments Requested AGENCY: Federal Communications Commission. ACTION: Notice;...

  14. 78 FR 66929 - Information Collection Being Reviewed by the Federal Communications Commission Under Delegated...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-07

    ...FEDERAL COMMUNICATIONS COMMISSION Information Collection Being Reviewed by the Federal Communications Commission Under Delegated Authority AGENCY: Federal Communications Commission. ACTION: Notice and...

  15. 78 FR 37809 - Information Collections Being Reviewed by the Federal Communications Commission Under Delegated...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-24

    ...FEDERAL COMMUNICATIONS COMMISSION Information Collections Being Reviewed by the Federal Communications Commission Under Delegated Authority AGENCY: Federal Communications Commission. ACTION: Notice and...

  16. 78 FR 55254 - Information Collection Being Reviewed by the Federal Communications Commission Under Delegated...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-09-10

    ...FEDERAL COMMUNICATIONS COMMISSION Information Collection Being Reviewed by the Federal Communications Commission Under Delegated Authority AGENCY: Federal Communications Commission. ACTION: Notice and...

  17. 76 FR 67451 - Information Collections Being Reviewed by the Federal Communications Commission Under Delegated...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-01

    ...FEDERAL COMMUNICATIONS COMMISSION Information Collections Being Reviewed by the Federal Communications Commission Under Delegated Authority AGENCY: Federal Communications Commission. ACTION: Notice and...

  18. 77 FR 66838 - Information Collection Being Reviewed by the Federal Communications Commission for Extension...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-11-07

    ...FEDERAL COMMUNICATIONS COMMISSION Information Collection Being Reviewed by the Federal Communications Commission for Extension Under Delegated Authority AGENCY: Federal Communications Commission. ACTION: Notice;...

  19. 78 FR 18338 - Information Collections Being Reviewed by the Federal Communications Commission, Comments Requested

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-26

    ...FEDERAL COMMUNICATIONS COMMISSION Information Collections Being Reviewed by the Federal Communications Commission, Comments Requested AGENCY: Federal Communications Commission. ACTION: Notice; request...

  20. 78 FR 28215 - Information Collection Being Reviewed by the Federal Communications Commission Under Delegated...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-14

    ...FEDERAL COMMUNICATIONS COMMISSION Information Collection Being Reviewed by the Federal Communications Commission Under Delegated Authority AGENCY: Federal Communications Commission. ACTION: Notice;...

  1. 77 FR 55838 - Information Collections Being Reviewed by the Federal Communications Commission Under Delegated...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-11

    ...FEDERAL COMMUNICATIONS COMMISSION Information Collections Being Reviewed by the Federal Communications Commission Under Delegated Authority AGENCY: Federal Communications Commission. ACTION: Notice and...

  2. 76 FR 49476 - Information Collection Being Reviewed by the Federal Communications Commission Under Delegated...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-10

    ...FEDERAL COMMUNICATIONS COMMISSION Information Collection Being Reviewed by the Federal Communications Commission Under Delegated Authority AGENCY: Federal Communications Commission. ACTION: Notice and...

  3. 76 FR 61699 - Information Collections Being Reviewed by the Federal Communications Commission Under Delegated...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-05

    ...FEDERAL COMMUNICATIONS COMMISSION Information Collections Being Reviewed by the Federal Communications Commission Under Delegated Authority AGENCY: Federal Communications Commission. ACTION: Notice and...

  4. 78 FR 34097 - Information Collections Being Reviewed by the Federal Communications Commission Under Delegated...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-06

    ...FEDERAL COMMUNICATIONS COMMISSION Information Collections Being Reviewed by the Federal Communications Commission Under Delegated Authority AGENCY: Federal Communications Commission. ACTION: Notice and...

  5. 78 FR 8528 - Information Collections Being Reviewed by the Federal Communications Commission Under Delegated...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-06

    ...FEDERAL COMMUNICATIONS COMMISSION Information Collections Being Reviewed by the Federal Communications Commission Under Delegated Authority AGENCY: Federal Communications Commission. ACTION: Notice and...

  6. A Security Architecture for Health Information Networks

    Microsoft Academic Search

    Rajashekar Kailar; Vinod Muralidhar

    Health information network security needs to balance exacting security controls with practicality, and ease of implementation in today's healthcare enterprise. Recent work on 'nationwide health information net- work' architectures has sought to share highly confidential data over insecure networks such as the Internet. Using basic patterns of health network data flow and trust models to support secure communica- tion between

  7. A communication architecture tailored for analog VLSI artificial neural networks: intrinsic performance and limitations

    Microsoft Academic Search

    Alessandro Mortara; Eric A. Vittoz

    1994-01-01

    An architecture for interchip communication among analog VLSI neural networks is proposed. Activity is encoded in a neuron's pulse emission frequency. Information is transmitted through the non-arbitered, asynchronous access of pulses to a common bus. The impact of collisions when the bus is accessed by more than one user is investigated. The information-carrying capability is assessed and the trade-off between

  8. "I'll See You on IM, Text, or Call You": A Social Network Approach of Adolescents' Use of Communication Media

    ERIC Educational Resources Information Center

    Van Cleemput, Katrien

    2010-01-01

    This study explores some possibilities of social network analysis for studying adolescents' communication patterns. A full network analysis was conducted on third-grade high school students (15 year olds, 137 students) in Belgium. The results pointed out that face-to-face communication was still the most prominent way for information to flow…

  9. Performance-aware Security of Unicast Communication in Hybrid Satellite Networks

    E-print Network

    Baras, John S.

    Performance-aware Security of Unicast Communication in Hybrid Satellite Networks Ayan Roy for securing the end-to-end communication in hybrid satellite networks. Satellite networks use TCP and HTTP communication in hybrid satellite networks. We therefore propose the use of the Layered IPSEC (LES) protocol

  10. Universities Water Information Network (UWIN)

    NSDL National Science Digital Library

    Based at Southern Illinois University in Carbondale, Illinois, the Universities Water Information Network (UWIN) is a USGS-funded meta-resource that centralizes water information on the WWW. The heart of the site is the searchable WRSIC (Water Resources Scientific Information Center) research abstracts bibliographic database, containing over 265,000 research abstracts and citations covering "a wide variety of (international) topics that span the time period from 1967 to October, 1993." Research abstracts in the database include "the life, physical, and social sciences, as well as engineering and legal issues." In addition to the database, UWIN offers tips for finding Water Resources on the Web (see the WetList section), as well as professional announcements, directories, and employment-related tips.

  11. Knowledge Communities and Information Network Policies.

    ERIC Educational Resources Information Center

    Young, Peter R.

    The growing convergence of research library functions with a knowledge network infrastructure is beginning to have a transforming influence on the conduct of university research and instruction. Computing and communication network technologies are forcing a re-examination of institutional missions, the policies that support knowledge transmission,…

  12. TRYPNET. New hemoparasite information network.

    PubMed

    Vokaty, S; Desquesnes, M; Applewhaite, L; Favre, J; Lieuw-A-Joe, R; Parris-Aaron, M; Bansse-Iisa, L

    1996-07-23

    Although Guyana, Suriname, and French Guiana share borders and climatic and geographic similarities, the countries have maintained little contact, due to language, political, and administrative differences. In 1993, two international organizations involved in the improvement of animal health, the Inter-American Institute for Cooperation on Agriculture (IICA) and CIRAD-EMVT (Centre de Cooperation Internationale en Recherche Agronomique pour le Developpement-Elevage et Medecine Veterinaire des Pays Tropicaux), jointly developed a collaborative project between the veterinary services of the three countries entitled "Hemoparasite Network for the Guianas." This project seeks to pool livestock, laboratory, and technical resources between the three countries in order to generate and exchange information on hemoparasites of livestock. A Hemoparasite Reference Laboratory for the Guianas has been created at the CIRAD-EMVT laboratory in Cayenne, French Guiana. Besides processing ruminant serum samples from the three countries, specialists from this organization conduct training in hemoparasite diagnostic techniques for laboratory personnel from Guyana and Suriname. A large-scale epidemiologic study of hemoparasites of cattle in the three countries is under way, to determine the prevalence, distribution, and clinical and economic significance of hemoparasites in the three countries, particularly Trypanosoma vivax and T. evansi. Preliminary results are presented and discussed. A Hemoparasite Information Network (TRYPNET) has been initiated, including a quarterly hemoparasite newsletter (TRYPNEWS), published in English and Spanish and disseminated to researchers in the Americas, Europe, and Africa. In 1995/96, it is proposed to expand the network's scope to include Venezuela and Brazil. PMID:8784498

  13. The information age as a work in progress: Implications for technical communicators

    SciTech Connect

    Preecs, B.L.

    1992-07-01

    The commercial media system in the United States is in the midst of radical, even revolutionary changes. Cable television companies are vying with telephone companies to provide advanced communications and information services to both homes and businesses. Recent decisions by the Federal Communications Commission to allow television networks to buy cable television systems create the possibility of bypassing local television stations. Computer companies are planning joint ventures with entertainment companies. The publishing, broadcasting, advertising, communications, and information-services businesses are converging into one universal, digital, interactive industry with annual revenues exceeding $120 billion. The same technology-driven changes also affect government. State and local governments are experimenting with delivering some government services electronically. While early experiments focus on easily delivered services, such as auto licenses, more complex applications are underway, such as creating information networks for economic development or converting property and utility records into computerized maps. The Information Age has arrived, and the implications for Society for Technical Communication (STC) members can hardly be overstated. Technical communicators will face changes in the way they work and how their work is distributed.

  14. Inferring Private Information Using Social Network Data

    E-print Network

    Kantarcioglu, Murat

    Inferring Private Information Using Social Network Data Jack Lindamood and Murat Kantarcioglu for released social networking data to infer undisclosed private in- formation about individuals. We purposes. These search results contained social security num- bers, addresses, and pornographic search

  15. Scheduling algorithms for arbitrary communication networks

    E-print Network

    Jagabathula, Srikanth

    2008-01-01

    We consider the problem of designing scheduling schemes for networks with arbitrary topology and scheduling constraints. We address the optimality of scheduling schemes for packet networks in terms of throughput, delay and ...

  16. 75 FR 26180 - Effects on Broadband Communications Networks of Damage To or Failure of Network Equipment or...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-11

    ...FEDERAL COMMUNICATIONS COMMISSION 47 CFR Chapter I [PS Docket...FCC 10-62] Effects on Broadband Communications Networks of Damage To or Failure of...or Severe Overload AGENCY: Federal Communications Commission. ACTION: Proposed...

  17. Progress on the Development of Future Airport Surface Wireless Communications Network

    NASA Technical Reports Server (NTRS)

    Kerczewski, Robert J.; Budinger, James M.; Brooks, David E.; Franklin, Morgan; DeHart, Steve; Dimond, Robert P.; Borden, Michael

    2009-01-01

    Continuing advances in airport surface management and improvements in airport surface safety are required to enable future growth in air traffic throughout the airspace, as airport arrival and departure delays create a major system bottleneck. These airport management and safety advances will be built upon improved communications, navigation, surveillance, and weather sensing, creating an information environment supporting system automation. The efficient movement of the digital data generated from these systems requires an underlying communications network infrastructure to connect data sources with the intended users with the required quality of service. Current airport surface communications consists primarily of buried copper or fiber cable. Safety related communications with mobile airport surface assets occurs over 25 kHz VHF voice and data channels. The available VHF spectrum, already congested in many areas, will be insufficient to support future data traffic requirements. Therefore, a broadband wireless airport surface communications network is considered a requirement for the future airport component of the air transportation system. Progress has been made on defining the technology and frequency spectrum for the airport surface wireless communications network. The development of a test and demonstration facility and the definition of required testing and standards development are now underway. This paper will review the progress and planned future work.

  18. AeroTCP: A Splitting Transport Protocol for an IP-based Satellite Network Supporting Aeronautical Communications

    E-print Network

    Baras, John S.

    Communications Yadong Shang* , Michael Hadjitheodosiou and John Baras Center for Satellite & Hybrid Communication to establish broadband aeronautical communication networks. Satellite network is recognized as one- ocean coverage. The expected advantages of the satellite systems for aeronautical communications also

  19. Pseudonymised communication in delay tolerant networks

    Microsoft Academic Search

    Naveed Ahmad; Haitham Cruickshank; Zhili Sun; Muhammad Asif

    2011-01-01

    Privacy, Anonymity, pseudonymity are the debatable terms which on one angle restrict the rights but on other angle open doors for malicious activity.This paper proposes design for a pseudonymised communication which is optimal solution for the privacy issues, where the real identity is hidden from the outside world by using blind signature in a different way of group communication.The protocol

  20. Multimedia Information Networks in Social Media

    NASA Astrophysics Data System (ADS)

    Cao, Liangliang; Qi, Guojun; Tsai, Shen-Fu; Tsai, Min-Hsuan; Pozo, Andrey Del; Huang, Thomas S.; Zhang, Xuemei; Lim, Suk Hwan

    The popularity of personal digital cameras and online photo/video sharing community has lead to an explosion of multimedia information. Unlike traditional multimedia data, many new multimedia datasets are organized in a structural way, incorporating rich information such as semantic ontology, social interaction, community media, geographical maps, in addition to the multimedia contents by themselves. Studies of such structured multimedia data have resulted in a new research area, which is referred to as Multimedia Information Networks. Multimedia information networks are closely related to social networks, but especially focus on understanding the topics and semantics of the multimedia files in the context of network structure. This chapter reviews different categories of recent systems related to multimedia information networks, summarizes the popular inference methods used in recent works, and discusses the applications related to multimedia information networks. We also discuss a wide range of topics including public datasets, related industrial systems, and potential future research directions in this field.

  1. Leveraging Information Technology. Track V: Communications.

    ERIC Educational Resources Information Center

    CAUSE, Boulder, CO.

    Seven papers from the 1987 CAUSE conference's Track V, Communications, are presented. They include: "University of Miami LAN: A Case Study" (Ruben Lopez and M. Lewis Temares); "Designing and Implementing an Integrated Communications Environment in a Small College" (Charles S. Garratt IV, Jack M. Lewis, and John L. Van Hemert); "Commonwealth of…

  2. Communication, advice exchange and job satisfaction of nursing staff: a social network analyses of 35 long-term care units

    PubMed Central

    2011-01-01

    Background The behaviour of individuals is affected by the social networks in which they are embedded. Networks are also important for the diffusion of information and the influence of employees in organisations. Yet, at the moment little is known about the social networks of nursing staff in healthcare settings. This is the first study that investigates informal communication and advice networks of nursing staff in long-term care. We examine the structure of the networks, how they are related to the size of units and characteristics of nursing staff, and their relationship with job satisfaction. Methods We collected social network data of 380 nursing staff of 35 units in group projects and psychogeriatric units in nursing homes and residential homes in the Netherlands. Communication and advice networks were analyzed in a social network application (UCINET), focusing on the number of contacts (density) between nursing staff on the units. We then studied the correlation between the density of networks, size of the units and characteristics of nursing staff. We used multilevel analyses to investigate the relationship between social networks and job satisfaction of nursing staff, taking characteristics of units and nursing staff into account. Results Both communication and advice networks were negatively related to the number of residents and the number of nursing staff of the units. Communication and advice networks were more dense when more staff worked part-time. Furthermore, density of communication networks was positively related to the age of nursing staff of the units. Multilevel analyses showed that job satisfaction differed significantly between individual staff members and units and was influenced by the number of nursing staff of the units. However, this relationship disappeared when density of communication networks was added to the model. Conclusions Overall, communication and advice networks of nursing staff in long-term care are relatively dense. This fits with the high level of cooperation that is needed to provide good care to residents. Social networks are more dense in small units and are also shaped by characteristics of staff members. The results furthermore show that communication networks are important for staff's job satisfaction. PMID:21631936

  3. Intrinsically secure communication in large-scale wireless networks

    E-print Network

    Pinto, Pedro C. (Pedro Correia)

    2010-01-01

    The ability to exchange secret information is critical to many commercial, governmental, and military networks. Information-theoretic security - widely accepted as the strictest notion of security - relies on channel coding ...

  4. Responder Communication Networks in the World Trade Center Disaster: Implications for Modeling of Communication Within Emergency Settings

    Microsoft Academic Search

    CARTER T. BUTTS; MIRUNA PETRESCU-PRAHOVA; B. REMY CROSS

    2007-01-01

    Using archival materials obtained from the Port Authority of New York and New Jersey, we analyze networks of communication and interaction among responders to the World Trade Center disaster. Our findings indicate substantial variability in individual radio communication system usage, with both communication volume and number of partners exhibiting distributions with long upper tails. Responder communication patterns are well-described by

  5. Deep Space Network information system architecture study

    NASA Technical Reports Server (NTRS)

    Beswick, C. A.; Markley, R. W. (editor); Atkinson, D. J.; Cooper, L. P.; Tausworthe, R. C.; Masline, R. C.; Jenkins, J. S.; Crowe, R. A.; Thomas, J. L.; Stoloff, M. J.

    1992-01-01

    The purpose of this article is to describe an architecture for the DSN information system in the years 2000-2010 and to provide guidelines for its evolution during the 1990's. The study scope is defined to be from the front-end areas at the antennas to the end users (spacecraft teams, principal investigators, archival storage systems, and non-NASA partners). The architectural vision provides guidance for major DSN implementation efforts during the next decade. A strong motivation for the study is an expected dramatic improvement in information-systems technologies--i.e., computer processing, automation technology (including knowledge-based systems), networking and data transport, software and hardware engineering, and human-interface technology. The proposed Ground Information System has the following major features: unified architecture from the front-end area to the end user; open-systems standards to achieve interoperability; DSN production of level 0 data; delivery of level 0 data from the Deep Space Communications Complex, if desired; dedicated telemetry processors for each receiver; security against unauthorized access and errors; and highly automated monitor and control.

  6. RF data communications considerations in advanced driver information systems

    Microsoft Academic Search

    Allan M. Kirson

    1991-01-01

    Advanced Driver Information Systems (ADIS)P, a subset of Intelligent Vehicle Highway Systems (IVHS), are considered. Some of the communications technologies that may be considered for IVHS\\/ADIS implementation are described, with an emphasis on wide-area RF data communications. The discussion covers communications between the infrastructure and the vehicle fleet, and not the connections between the roadside equipment and the traffic management

  7. Networked Operations of Hybrid Radio Optical Communications Satellites

    NASA Technical Reports Server (NTRS)

    Hylton, Alan; Raible, Daniel

    2014-01-01

    In order to address the increasing communications needs of modern equipment in space, and to address the increasing number of objects in space, NASA is demonstrating the potential capability of optical communications for both deep space and near-Earth applications. The Integrated Radio Optical Communications (iROC) is a hybrid communications system that capitalizes on the best of both the optical and RF domains while using each technology to compensate for the other's shortcomings. Specifically, the data rates of the optical links can be higher than their RF counterparts, whereas the RF links have greater link availability. The focus of this paper is twofold: to consider the operations of one or more iROC nodes from a networking point of view, and to suggest specific areas of research to further the field. We consider the utility of Disruption Tolerant Networking (DTN) and the Virtual Mission Operation Center (VMOC) model.

  8. Latin American Network Information Center

    NSDL National Science Digital Library

    Started in 1992 and affiliated with the Lozano Long Institute of Latin American Studies at the University of Texas at Austin, the Latin American Network Information Center (LANIC) is designed to "facilitate access to Internet-based information to, from, or on Latin America." Their site was redesigned in the spring of 2008, and currently their various directories contain over 12,000 unique URLs for use by the general public. These links can be browsed by subject headings or by country, and visitors can look into more discrete topical headings like "food", "political science", and "social work". Along with these high-quality links, visitors can then click on over to their "Digital Initiatives" area. Here they will find digital collections that cover documents from the New Mexican Revolution and the full-text Fidel Castro Speech database. Visitors will also appreciate that many of the site's resources are available in Spanish and Portuguese.

  9. Secure Communication among Cell Phones and Sensor Networks

    Microsoft Academic Search

    Arjan Durresi; Vamsi Paruchuri

    2009-01-01

    Numerous applications, ranging from disaster management to smart buildings, have been proposed for sensor networks. The practicality of these applications depends on the ability of users to interact with these networks, in many cases in real time. In this paper we propose that cell phones interact with sensor networks and obtain the relevant information in real time. Cell phones can

  10. A 12-transistor PFM demodulator for analog neural networks communication

    Microsoft Academic Search

    Alessandro Mortara; Eric A. Vittoz

    1995-01-01

    Pulse frequency modulation (PFM) provides robust long-distance communication and event-driven access to the communication channel. A PFM demodulator small and simple enough to equip every cell of a large analog neural network is analyzed. The circuit can demodulate PFM signals with pulse rates as low as 1 kHz using the switched-capacitor technique. Measurement results from integrated demodulators are presented

  11. Powerline communications interface in CSMA\\/CA-networks

    Microsoft Academic Search

    H. Beikirch; M. Voss

    2003-01-01

    The utilization of existing powerlines for communication purposes opens many possibilities, which can be advantageous for a wide range of field bus applications. Known home automation solutions have low transmission speeds (e.g. EIB, LON) or works with other packet-oriented communication techniques (OFDM- or TDMA-based technologies). Networks with CSMA\\/CA access (e.g. SCAN) requires minimized signal delay times because this delay limits

  12. Real-time communication in multi-hop networks

    Microsoft Academic Search

    Dilip D. Kandlur; Kang G. Shin; Domenico Ferrari

    1991-01-01

    Communication in real-time systems has to be predictable, because unpredictable delays inthe delivery of messages can adversely affect the execution of tasks dependent on these messages.In this paper, we develop a scheme for providing predictable inter-process communication inreal-time systems with (partially connected) point--to--point interconnection networks, whichprovides guarantees on the maximum delivery time for messages. This scheme is based on theconcept

  13. Distance Preferences Small-World Communication Topology for Agent Network

    NASA Astrophysics Data System (ADS)

    Wu, Zhengping; Wang, Renming

    In multi-agent system (MAS), the communication topology of agent network plays a very important role in its collaboration. Small-world networks are the networks with high local clustering and small average path length, and the communication networks of MAS can be analyzed within the frame of small-world topology. Yet the real multiagent communication networks are abundant and the classical WS small-world model is not suitable for all cases. In this paper, two new small-world network models are presented. One is based on random graph substrate and local nodes preference reconnection and the other is based on regular graph substrate and long-range nodes preference reconnection. The characteristic of the network parameter such as the clustering coefficients, average path length, and eigenvalue ?2 and ?n of the Laplacian matrix for these two models and WS model is studied. The consensus problem that based on these three models is also studied. An example is given and the conclusions are made in the end.

  14. Isochronal synchronization in networks and chaos-based TDMA communication

    NASA Astrophysics Data System (ADS)

    Grzybowski, J. M. V.; Macau, E. E. N.; Yoneyama, T.

    2014-06-01

    Pairs of delay-coupled chaotic systems were shown to be able to achieve isochronal synchronization under bidirectional coupling and self-feedback. Such identical-in-time behavior was demonstrated to be stable under a set of conditions and to support simultaneous bidirectional communication between pairs of chaotic oscillators coupled with time-delay. More recently, it was shown that isochronal synchronization can emerge in networks with several hundreds of oscillators, which allows its exploitation for communication in distributed systems. In this paper, we introduce a conceptual framework for the application of isochronal synchronization to TDMA communication in networks of delay-coupled chaotic oscillators. On the basis of the stable and identical-in-time behavior of delay-coupled chaotic systems, the chaotic dynamics of distributed oscillators is used to support and sustain coordinate communication among nodes over the network. On the basis of the unique features of chaotic systems in isochronal synchronization, the chaotic signals are used to timestamp clock readings at the physical layer such that logical clock synchronization among the nodes (a prerequisite for TDMA) can be exploited using the same basic structure. The result is a standalone network communication scheme that can be advantageously applied in the context of ad-hoc networks or alike, especially short-ranged ones that yield low values of time-delay. As explored to its depths in practical implementations, this conceptual framework is argued to have potential to provide gain in simplicity, security and efficiency in communication schemes for autonomous/standalone network applications.

  15. Securing against fraud in mobile communications : system design and development in 3G mobile networks

    E-print Network

    Mochizuki, Yujiro, 1973-

    2006-01-01

    Network security ensures the consistency, integrity, and reliability of telecommunications systems. Authorized network access prevents fraudulent communications and maintains the availability of the systems. However, limited ...

  16. NICTA Report 2010 Information and Communications Technology (ICT) is

    E-print Network

    Heiser, Gernot

    -inspired basic research that benefits industry, the community and the national interest. RESEARCH NICTA hasNICTA Report 2010 #12;Information and Communications Technology (ICT) is everywhere, from communications hub that is the Internet. Often invisible and taken for granted, these technologies would

  17. Informing Workers of Chemical Hazards: The OSHA Hazard Communication Standard.

    ERIC Educational Resources Information Center

    American Chemical Society, Washington, DC.

    Practical information on how to implement a chemical-related safety program is outlined in this publication. Highlights of the federal Occupational Safety and Health Administrations (OSHA) Hazard Communication Standard are presented and explained. These include: (1) hazard communication requirements (consisting of warning labels, material safety…

  18. Information, Network & Cyber Security School COMSC

    E-print Network

    Martin, Ralph R.

    Information, Network & Cyber Security School COMSC Information security officers are faced with strategic decisions on a daily basis, and are required to make informed decisions on the security options of information security and privacy within the context of strategic information systems and also computer

  19. A secure communication suite for underwater acoustic sensor networks.

    PubMed

    Dini, Gianluca; Lo Duca, Angelica

    2012-01-01

    In this paper we describe a security suite for Underwater Acoustic Sensor Networks comprising both fixed and mobile nodes. The security suite is composed of a secure routing protocol and a set of cryptographic primitives aimed at protecting the confidentiality and the integrity of underwater communication while taking into account the unique characteristics and constraints of the acoustic channel. By means of experiments and simulations based on real data, we show that the suite is suitable for an underwater networking environment as it introduces limited, and sometimes negligible, communication and power consumption overhead. PMID:23202204

  20. Topology-aware overlay networks for group communication

    Microsoft Academic Search

    Minseok Kwon; Sonia Fahmy

    2002-01-01

    We propose an application level multicast approach, Topology Aware Grouping (TAG), which exploits underlying network topology information to build efficient overlay networks among multicast group members. TAG uses information about path overlap among members to construct a tree that reduces the overlay relative delay penalty, and reduces the number of duplicate copies of a packet on the same link. We

  1. Information theory, animal communication, and the search for extraterrestrial intelligence

    Microsoft Academic Search

    Laurance R. Doyle; Brenda McCowan; Simon Johnston; Sean F. Hanser

    2011-01-01

    We present ongoing research in the application of information theory to animal communication systems with the goal of developing additional detectors and estimators for possible extraterrestrial intelligent signals. Regardless of the species, for intelligence (i.e., complex knowledge) to be transmitted certain rules of information theory must still be obeyed. We demonstrate some preliminary results of applying information theory to socially

  2. Inter-vehicle communications: assessing information dissemination under safety constraints

    Microsoft Academic Search

    Marc Torrent-Moreno

    2007-01-01

    The main goal of inter-vehicle communication technologies is to provide each vehicle with the required information about its surrounding in order to assist the driver avoiding potential dangers. The required information level, or awareness, can be achieved by the exchange of periodic status messages (beacons) among neighboring vehicles together with the quick dissemination of information about potential hazards. In previous

  3. NASCOM network ground communications availability report

    NASA Technical Reports Server (NTRS)

    1983-01-01

    A performance analysis of NASCOM Network circuits is presented. An objective of 99.80 percent availability has been established for all network circuits and an acceptable level of 99.50. A network narrative summary for the current month includes changes in network configurations, current month's totals for modes of service and trouble category losses, a discussion of trends, and significant losses that affected the performance indexes of individual or groups of circuits. A table and narrative summary of those circuits that failed to meet the objective of 99.80% availability for all network circuits and an acceptable level of 99.50. Lost time and interruption tables showing all circuits affected by outages, by trouble category, with their total time and events, scheduled operating hours, and individual availability indexes also are included. Selected circuits whose availabilities have or continue to affect the overall network availability are also analyzed.

  4. Communication Dynamics of Blog Networks Mark Goldberg

    E-print Network

    Magdon-Ismail, Malik

    on the Russian section of LiveJournal as a case study. Communications (blogger-to-blogger links) in such online, though the set of bloggers remains approximately con- stant. Two fundamental questions are: (i) what

  5. Research on key issues of information acquisition in wireless sensor networks

    Microsoft Academic Search

    ZANG Chuan-zhen; FAN Yu-shun

    Wireless Sensor Networks (WSNs) represent an important research field in information technology domain and could find their applications in many kinds of aspects. The architecture of information acquisition for WSNs is presented,and the key issues on information acquisition as well as the analysis of their drawbacks and technical trends are described. Especially, the key problems in communication are

  6. A Unix network protocol security study: network information service

    Microsoft Academic Search

    David K. Hess; David R. Safford; Udo W. Pooch

    1992-01-01

    This note is a study of the security weaknesses present in a widely used Unix network protocol, Network Information Service (NIS). NIS (formerly known as Yellow Pages or YP) was developed by Sun Microsys-tems primarily to reduce the effort required to setup and maintain a network of Unix workstations. This is accomplished through the centralization on a NIS server of

  7. Power, Avionics and Software Communication Network Architecture

    NASA Technical Reports Server (NTRS)

    Ivancic, William D.; Sands, Obed S.; Bakula, Casey J.; Oldham, Daniel R.; Wright, Ted; Bradish, Martin A.; Klebau, Joseph M.

    2014-01-01

    This document describes the communication architecture for the Power, Avionics and Software (PAS) 2.0 subsystem for the Advanced Extravehicular Mobile Unit (AEMU). The following systems are described in detail: Caution Warn- ing and Control System, Informatics, Storage, Video, Audio, Communication, and Monitoring Test and Validation. This document also provides some background as well as the purpose and goals of the PAS project at Glenn Research Center (GRC).

  8. Automotive suspension control through a computer communication network

    Microsoft Academic Search

    U. Ozguner; H. Goktas; H. Chant; J. Winkelman; M. Liubakka; R. Krtolica

    1992-01-01

    Closed-loop stability and performance-related studies performed on a multiplex communication network called Carlink, being considered for automotive applications, are discussed. Tests done on an automotive suspension control model, in which the active control signal is applied through the multiplex network as a real-time hybrid computer\\/hardware-in-the-loop experiment are outlined. The stability of the system is considered using analytical approaches developed by

  9. MiniSec: a secure sensor network communication architecture

    Microsoft Academic Search

    Mark Luk; Ghita Mezzour; Adrian Perrig; Virgil D. Gligor

    2007-01-01

    Secure sensor network communication protocols need to provide three basic properties: data secrecy, authentication, and replay pro- tection. Secure sensor network link layer protocols such as Tiny- Sec (10) and ZigBee (24) enjoy signicant attention in the com- munity. However, TinySec achieves low energy consumption by reducing the level of security provided. In contrast, ZigBee enjoys high security, but suffers

  10. Information spread of emergency events: path searching on social networks.

    PubMed

    Dai, Weihui; Hu, Hongzhi; Wu, Tunan; Dai, Yonghui

    2014-01-01

    Emergency has attracted global attentions of government and the public, and it will easily trigger a series of serious social problems if it is not supervised effectively in the dissemination process. In the Internet world, people communicate with each other and form various virtual communities based on social networks, which lead to a complex and fast information spread pattern of emergency events. This paper collects Internet data based on data acquisition and topic detection technology, analyzes the process of information spread on social networks, describes the diffusions and impacts of that information from the perspective of random graph, and finally seeks the key paths through an improved IBF algorithm. Application cases have shown that this algorithm can search the shortest spread paths efficiently, which may help us to guide and control the information dissemination of emergency events on early warning. PMID:24600323

  11. Asset pricing in large information networks

    Microsoft Academic Search

    Han N. Ozsoylev; Johan Walden

    2011-01-01

    We study asset pricing in economies with large information networks. We focus on networks that are sparse and have power law degree distributions, in line with empirical studies of large scale social networks. Our theoretical framework yields a rich set of novel asset pricing implications. We derive closed form expressions for price, volatility, profitability and trading volume, as functions of

  12. NETWORKS, NETWAR, AND INFORMATION AGE TERRORISM

    Microsoft Academic Search

    John Arquilla; David Ronfeldt; Michele Zanini

    The rise of network forms of organization is a key consequence of the ongoing information revolution. Business organizations are being newly energized by networking, and many professional militaries are experimenting with flatter forms of organization. In this chapter, we explore the impact of networks on terrorist capabilities, and consider how this development may be associated with a move away from

  13. Predicting Information Flows in Network Traffic.

    ERIC Educational Resources Information Center

    Hinich, Melvin J.; Molyneux, Robert E.

    2003-01-01

    Discusses information flow in networks and predicting network traffic and describes a study that uses time series analysis on a day's worth of Internet log data. Examines nonlinearity and traffic invariants, and suggests that prediction of network traffic may not be possible with current techniques. (Author/LRW)

  14. Planning Communication Networks to Deliver Educational Services.

    ERIC Educational Resources Information Center

    Ballard, Richard J.; Eastwood, Lester F., Jr.

    As companion to the more general document Telecommunications Media for the Delivery of Educational Programming , this report concentrates on the technical and economic factors affecting the design of only one class of educational networks, dedicated coaxial cable systems. To provide illustrations, possible single and dual dedicated cable networks

  15. Wireless communications and networking: an overview

    Microsoft Academic Search

    R. Jordan; C. T. Abdallah

    2002-01-01

    This paper presents an overview of wireless local-area networks (LANs) and wireless personal area networks (PANS), with emphasis on the two most popular standards: IEEE 802.11, and Bluetooth. While there are many such surveys in the current literature and online, we attempt here to present wireless LANs and PANS in a unified fashion as a viable alternative to wired LANs,

  16. ITCS6168/8168 Wireless Communications & Networks

    E-print Network

    Wang, Yu

    in-class presentation, a midterm exam, and a final exam. They will count toward the grade as follows or Optics and a prior course in networking Course Content: The course provides an overview of mobile systems and wireless networking technologies. Emphasis will be on different wireless and mobile systems and basic

  17. ITCS6168/8168 Wireless Communications & Networks

    E-print Network

    Wang, Yu

    systems and basic resource management, routing and quality of service at the MAC and networking layers, a midterm exam, and a final exam. They will count toward the grade as follows: Homework 30% In of mobile systems and wireless networking technologies. Emphasis will be on different wireless and mobile

  18. Editorial: Hybrid and Sattelite Communication Networks

    Microsoft Academic Search

    Anthony Ephremides; Francesco Vatalaro

    1998-01-01

    Abstract This paper describes experiments conducted over ACTS and the associated T1 VSAT terminal The experiments were motivated by the commercial potential of low - cost receive - only satellite terminals that can operate in a hybrid network environment, and by the desire to demonstrate frame relay technology over satellite networks The rst experiment tested highly adaptive methods of satellite

  19. Family: Family: Function Broadcast Communications Publications and Production Function: Applications Programming Information Systems

    E-print Network

    Westerling, Anthony L.

    : ·Applications Programming ·Information Systems ·Electronic Communications ·Visual Communications ·AV IT ·IT Training ·Health Education ·Admissions/Recruitment ·Student Academic Advising ·Counseling Architecture ·General Communications ·Written Communications ·AV IT Engineering ·IT Security ·Media

  20. Communications and Networking for Smart Grid: Technology and Practice , HossamS. Hassanein2

    E-print Network

    Qiu, Robert Caiming

    Editorial Communications and Networking for Smart Grid: Technology and Practice Chi Zhou1 , Hossam for Smart Grid research and development, so the communications networks in Smart Grid must facilitate communications protocols, and provide secure and reliable communications for the smart grid. Many open issues

  1. Handoff\\/resource managements based on PVCs and SVCs in broadband personal communication networks

    Microsoft Academic Search

    Duk Kyung Kim; Dan Keun Sung

    1996-01-01

    Current mobile communication systems with their fixed network infrastructures may be inadequate to accommodate future multimedia mobile services. We introduce an architecture of broadband personal communication networks (BPCN) as a future mobile communication network integrated with B-ISDN\\/ATM based infrastructures and propose two resource management schemes based on PVC and SVC concepts. We also propose a PVC based fast handoff mechanism

  2. Towards a Unified Policy Language for Future Communication Networks: A Process

    E-print Network

    Kokar, Mieczyslaw M.

    Towards a Unified Policy Language for Future Communication Networks: A Process Mieczyslaw M. Kokar1 an integrated set of ontologies for the particular sub-domains of network communication and a formal language their communications and networking needs. Figure 1. Actors, issues and standard languages: a conceptual view [1

  3. Communicating genetic information: a difficult challenge for future pediatricians

    PubMed Central

    2007-01-01

    Background The role of the pediatrician as genetic counselor is ideal because pediatricians have medical knowledge and experience with genetic disorders (e.g. Down syndrome). Moreover, pediatricians can provide comprehensive care in a medical home to patients with genetic disorders. However, changes in the curriculum of the pediatric resident are necessary to address the future challenges of effectively communicating genetic information to patients. The objective of this study was to explore these challenges and make recommendations for training to adequately prepare pediatricians for their future role as genetic counselors. Methods Three reviewers independently searched PubMed, OVID, and Medline databases to identify articles describing the challenges of communicating genetic information to patients, published from 1960 to December 2005. After the publications were identified and reviewed, four major areas of interest were identified in order to categorize the findings. Results Twenty-five publications were identified during the literature search. From the review, the following categories were selected to organize the findings: (1) Inherent difficulties of communicating and comprehending genetic information; (2) Comprehension of genetic information by pediatricians; (3) Genetics training in residency programs; and (4) The effect of genetic information on the future role of pediatricians and potential legal implications. Conclusion Pediatricians and residents lack essential knowledge of genetics and communication skills for effective counseling of patients. The review indicated that successful communication of genetic information involves a number of important skills and considerations. It is likely that these skills and considerations are universally required for the communication of most complex specialized medical information. In the past, communication skills have not been considered a priority. Today, these skills have become a demanding professional and even legal obligation. However, the challenges involved in communicating complex medical information cannot be successfully addressed with universal, one-size-fits-all recommendations. Residency training programs require changes to adequately prepare future pediatricians for the growing challenge of communicating genetic information. Four important skills should be considered in the training of residents to improve the communication of complex information to patients. These skills are (1) discriminating, (2) understanding, (3) simplifying, and (4) explaining information. PMID:17577408

  4. Scientific Information Networks: A Case Study.

    ERIC Educational Resources Information Center

    Vallee, Jacques

    The technical feasibility of a continental information network for astronomy has been demonstrated in the course of a two-month experiment conducted jointly by Dearborn Observatory of Northwestern University and the Stanford University Computation Center. The experiment simulated a scientific information network based on a high-level retrieval…

  5. ISO/OSI satellite communication network

    NASA Astrophysics Data System (ADS)

    Birch, David G. W.

    A strategy for the specification and implementation of a Very Small Aperture Terminal (VSAT) Managed Network Service is presented, based on the International Standards Organization (ISO) specification processes, ISO 7498. The management strategy for the system configuration, security, faults, accounting, performance, and user interface are described. The implementation strategy advocates the maximum use of off-the-shelf components and the development of standard gateways and packet assembler/dissassembler architectures. It is found that the VSAT network can support functions such as point-to-multipoint transmission and group addressing at the network layer.

  6. Research on power communication network real-time based on OPNET simulator

    Microsoft Academic Search

    Liuyan Huang; Rong Zong; Jiang Yu; Jinsong Hu; Ling Zhao; Jun Chang

    2012-01-01

    In this paper, the OPNET modeling technology is adopted to study the end-to-end real-time performance of service data stream in power communication network in detail. PTN network technology is used to establish PTN test network simulation model of power communication network, and analyze characteristics of data flow in power communication network, message transmission process and packet end-to-end delay. Specific research

  7. Applying Model Based Systems Engineering to NASA's Space Communications Networks

    NASA Technical Reports Server (NTRS)

    Bhasin, Kul; Barnes, Patrick; Reinert, Jessica; Golden, Bert

    2013-01-01

    System engineering practices for complex systems and networks now require that requirement, architecture, and concept of operations product development teams, simultaneously harmonize their activities to provide timely, useful and cost-effective products. When dealing with complex systems of systems, traditional systems engineering methodology quickly falls short of achieving project objectives. This approach is encumbered by the use of a number of disparate hardware and software tools, spreadsheets and documents to grasp the concept of the network design and operation. In case of NASA's space communication networks, since the networks are geographically distributed, and so are its subject matter experts, the team is challenged to create a common language and tools to produce its products. Using Model Based Systems Engineering methods and tools allows for a unified representation of the system in a model that enables a highly related level of detail. To date, Program System Engineering (PSE) team has been able to model each network from their top-level operational activities and system functions down to the atomic level through relational modeling decomposition. These models allow for a better understanding of the relationships between NASA's stakeholders, internal organizations, and impacts to all related entities due to integration and sustainment of existing systems. Understanding the existing systems is essential to accurate and detailed study of integration options being considered. In this paper, we identify the challenges the PSE team faced in its quest to unify complex legacy space communications networks and their operational processes. We describe the initial approaches undertaken and the evolution toward model based system engineering applied to produce Space Communication and Navigation (SCaN) PSE products. We will demonstrate the practice of Model Based System Engineering applied to integrating space communication networks and the summary of its results and impact. We will highlight the insights gained by applying the Model Based System Engineering and provide recommendations for its applications and improvements.

  8. The Parrot is Dead: Observing Unobservable Network Communications

    E-print Network

    Shmatikov, Vitaly

    Vitaly Shmatikov The University of Texas at Austin Abstract--In response to the growing popularity of Tor. Keywords-Censorship circumvention; unobservable commu- nications; Tor pluggable transports I. INTRODUCTION Censorship-resistant communication systems such as the Tor anonymity network1 are increasingly used by people

  9. The Role and Future Challenges of Wireless Communication Networks for

    E-print Network

    Boyer, Edmond

    of future wireless communi- cation networks for autonomous city vehicles. After addressing the state of technology, the paper explains the autonomous vehicle control system architecture and the Cybercars-2 abilities of autonomous vehicles in urban environments. Keywords: communication for autonomous city vehicles

  10. Reevaluation of RF electromagnetic communication in underwater sensor networks

    Microsoft Academic Search

    Xianhui Che; Ian Wells; Gordon Dickers; Paul Kear; Xiaochun Gong

    2010-01-01

    Most underwater wireless networks use acoustic waves as the transmission medium nowadays, but the chances of getting much more out of acoustic modems are quite remote. Optical links are impractical for many underwater applications. Given modern operational requirements and digital communications technology, the time is now ripe for re-evaluating the role of electromagnetic signals in underwater environments. The research presented

  11. A Future Internet Architecture supporting Multipath Communication Networks

    E-print Network

    Dreibholz, Thomas

    A Future Internet Architecture supporting Multipath Communication Networks Martin Becke, Thomas.becke,dreibh,hakim.adhari,rathgeb}@iem.uni-due.de Abstract--The classic layered OSI reference model has reached its limits for the Internet of today discussion on the Future Internet. We address the shortcomings of the layered model by redesigning

  12. Global Mobility Management by Replicated Databases in Personal Communication Networks*

    E-print Network

    Leung, Kin K.

    [GPM92] has been established as an industry standard in the Global System for Mobile Telecommunication with industry protocol standards - and compare them with the traditional, centralized database scheme telecommunication services, such as Personal Communication and Software Defined Network (SDN) services, today

  13. Reliability and Throughput in Future Automotive Communication Networks

    E-print Network

    Rajkumar, Ragunathan "Raj"

    Reliability and Throughput in Future Automotive Communication Networks John Liu, Timothy TaltyStar. This action created a new industry called automotive telematics, helping to save lives and providing, the automotive telematics industry has experienced a healthy growth in North America. During the current economic

  14. Swarm Intelligence for Routing in Communication Networks I. Kassabalidis*

    E-print Network

    Arabshahi, Payman

    Swarm Intelligence for Routing in Communication Networks I. Kassabalidis* , M.A. El-Sharkawi* , R.J.Marks II* , P. Arabshahi , A.A. Gray ,_ Abstract ­ Swarm intelligence, as demonstrated by natural analytically understanding and extending the design principles and operations exhibited by intelligent

  15. CMPSCI 791N: Algorithms for Communication Networks Reading List

    E-print Network

    Adler, Micah

    . Rosenberg, Ramesh K. Sitaraman, and Walter Unger, Scheduling Time­Constrained Communication in Linear­packet delay guarantees of O(distance + 1/session rate). In 38th IEEE Symp. on Foundations of Computer Science Computing (PODC) 1999. 1 #12; Ad­Hoc Wireless Networks ffl Combined presentation: -- R. Bar­Yehuda, O

  16. On the Reliability of Wireless Sensor Networks Communications

    E-print Network

    Paris-Sud XI, Université de

    On the Reliability of Wireless Sensor Networks Communications Alexandre Mouradian and Isabelle Aug applications, which must meet time and reliability requirements. Works on the real-time ca- pability of WSNs have been proposed [1]. In this paper we propose to study the achievable reliability of WSNs, tacking

  17. Generating UAV Communication Networks for Monitoring and Surveillance

    E-print Network

    Doherty, Patrick

    Generating UAV Communication Networks for Monitoring and Surveillance Per-Magnus Olsson, Jonas, especially when smaller UAVs are used. Both problems can be solved to creating relay chains for surveillance different trade-offs between the number of UAVs in the chain and the chain's cost. We also show new results

  18. Adaptive MAC Protocol for UAV Communication Networks Using Directional Antennas

    E-print Network

    Dong, Liang

    Adaptive MAC Protocol for UAV Communication Networks Using Directional Antennas Abdel Ilah Alshbatat and Liang Dong, Senior Member, IEEE Abstract-- Unmanned aerial vehicle (UAV) has been used inspection and range extension. Moreover, UAVs are suited for situations that are too dangerous for direct

  19. Improving TCP performance in integrated wireless communications networks

    E-print Network

    Ansari, Nirwan

    + 3G cellular systems, illustrated in Fig. 1, more data and multi- media communications are carried an error-free and congestion-free reverse channel that has the same capacity as the forward channel and cellular networks stretch the Internet beyond the limits of geography and terrain. In integrated WAN + LAN

  20. Statistical Modeling of Social Groups on Communication Networks Mark Goldberg

    E-print Network

    Magdon-Ismail, Malik

    Polytechnic Institute goldberg@cs.rpi.edu Paul Horn Rensselaer Polytechnic Institute hornp@cs.rpi.edu Malik. We present preliminary results on some newsgroup societies. Contact: Prof. Malik Magdon-Ismail, Dept Groups on Communication Networks Mark Goldberg, Paul Horn, Malik Magdon-Ismail, Jessie Riposo, David

  1. Communication Networks Simple tariffs based on price multipliers for

    E-print Network

    Communication Networks Simple tariffs based on price multipliers for ATM VBR services COSTAS an approach for constructing simple time­based tariffs for Variable Bit Rate (VBR) connections from Constant tariffs for Service Level Agreements (SLAs) where the maximum amount of conforming traffic is given

  2. Communication Networks Simple tariffs based on price multipliers for

    E-print Network

    Communication Networks Simple tariffs based on price multipliers for ATM VBR services COSTAS an approach for constructing simple time-based tariffs for Variable Bit Rate (VBR) connections from Constant tariffs for Service Level Agreements (SLAs) where the maximum amount of conforming traffic is given

  3. Indian-Spanish Communication Networks: Continuity in the Greater Southwest.

    ERIC Educational Resources Information Center

    Riley, Carroll L.; Manson, Joni L.

    Trade and communication networks established by Indian groups in the 15th century A.D. linked the Southwest to Mesoamerica, the Plains and the Pacific littoral; these routes were later used by the Spanish and Americans, and today major highways follow ancient Indian routes. The main east-west route had major termini at Cibola (near Zuni) in the…

  4. Energy-Efficient Communication Protocol for Wireless Microsensor Networks

    Microsoft Academic Search

    Wendi Rabiner Heinzelman; Anantha Chandrakasan; Hari Balakrishnan

    2000-01-01

    Wireless distributed microsensor systems will enable the reliable monitoring of a variety of environments for both civil and military applications. In this paper, we look at communication protocols, which can have significant im- pact on the overall energy dissipation of these networks. Based on our findings that the conventional protocols of direct transmission, minimum-transmission-energy, multi- hop routing, and static clustering

  5. Saddle Policies for Secure Routing in Communication Networks1

    Microsoft Academic Search

    Stephan Bohacek; Joao P. Hespanha; Katia Obraczka

    2002-01-01

    In this paper we formalize routing in communication networks as a game between the designer of the routing algorithm and an attacker that attempts to intercept packets. By computing saddle-point solutions to this game, we obtain stochastic routing policies that are secure in the sense that they utilize multiple paths to minimize the probability of packet interception. We also show

  6. A Network Level Channel Abstraction for Multimedia Communication in Real-Time Networks

    Microsoft Academic Search

    Taieb Znati; Brian Field

    1993-01-01

    The design of communication protocols to support guaranteed real-time communication for distributed multimedia systems is examined. A network level abstraction called phi -channel that supports the requirements of real-time applications is proposed. A phi -channel represents a fractional, simplex, end-to-end communication channel between a source and a destination. The channel is characterized by a set of specific performance parameters associated

  7. 76 FR 32360 - Information Collection Being Reviewed by the Federal Communications Commission

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-06

    ...comments to the Federal Communications Commission via e-mail...Miscellaneous Wireless Communications Services in the 2...Form No.: N/A. Type of Review: New information...information filed by Wireless Communications Service (WCS)...

  8. 75 FR 69439 - Notice of Public Information Collection(s) Being Reviewed by the Federal Communications...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-12

    ...FEDERAL COMMUNICATIONS COMMISSION Notice of Public Information...s) Being Reviewed by the Federal Communications Commission for Extension Under Delegated...November 3, 2010. SUMMARY: The Federal Communications Commission, as part of its...

  9. 75 FR 69437 - Notice of Public Information Collection(s) Being Reviewed by the Federal Communications...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-12

    ...FEDERAL COMMUNICATIONS COMMISSION Notice of Public Information...s) Being Reviewed by the Federal Communications Commission, Comments Requested November...C. 3501-3520), the Federal Communications Commission invites the general...

  10. An adaptive digital beamforming network for satellite communication systems

    NASA Astrophysics Data System (ADS)

    Barrett, M.; Fernandez, J.; Lagunas, M. A.; Coromina, F.

    1991-10-01

    The use of adaptive digital beamforming techniques has, until recently, been largely restricted to high performance military radar systems. Recent advances in digital technology, however, have enabled the design of single chip digital beamforming networks. This, coupled with advances in digital signal processor technology, enables complete beamforming systems to be constructed at a lower cost, thus making the application of these techniques to commercial communications systems attractive. The design and development of such an adaptative digital beamforming network are described. The system is being developed as a proof of concept laboratory based demonstrator to enable the feasibility of adaptive digital beamforming techniques for communication systems to be determined. Ultimately, digital beamforming could be used in conjunction with large array antennas for communication satellite systems. This will enable the simultaneous steering of high gain antenna beams in the direction of ground based users and the nulling of unwanted interference sources, such as radar systems, to be performed.

  11. Cooperative Communication Protocols in Wireless Networks: Performance Analysis and Optimum Power Allocation

    Microsoft Academic Search

    Weifeng Su; Ahmed K. Sadek; K. J. Ray Liu

    2008-01-01

    In this paper, symbol-error-rate (SER) performance analysis and optimum power allocation are provided for uncoded cooperative\\u000a communications in wireless networks with either decode-and-forward (DF) or amplify-and-forward (AF) cooperation protocol,\\u000a in which source and relay send information to destination through orthogonal channels. In case of the DF cooperation systems,\\u000a closed-form SER formulation is provided for uncoded cooperation systems with PSK and

  12. Processor allocation and communication in networks

    SciTech Connect

    Al-Dhelaan, A.M.

    1989-01-01

    The author will describe two known strategies for static processor allocation in an n-cube multiprocessor, namely the buddy system strategy and the gray code strategy, and then propose a new strategy that out-performs the first by (n-k+1) and the second by (n-k+1)/2 in cube recognition. Furthermore, his strategy is suitable for static as well as dynamic processor allocation and results in less system fragmentation, more subcubes recognition and higher fault tolerance. He also introduces an extension to strategy that will enhance the performance drastically so that his algorithm, together with the extension, will outperform the buddy system and the gray strategy. The cube-connected cycles network is an attractive alternative for the n-cube, since it overcomes the degree problem by limiting it to 3. He proposes and studies cube-connected cycles networks that are missing some of their cycles, called incomplete cube-connected cycles networks. These incomplete cube-connected cycles networks can be used to interconnect systems with any number of processors, thus overcoming the severe restriction of the complete cube-connected cycles networks. In incomplete cube-connected networks the processors are well utilized, routes are shorter and the layout area is a lot smaller. He developed efficient routing and broadcasting algorithms and shows how to lay this network on a chip. Broadcasting is a procedure by which a processor can pass a message to all other processors in the network nonredundantly. He briefly describes the algorithm for broadcasting in the hypercube developed by Sullivan and Bashkow, than he develops a simple yet efficient fault tolerant broadcasting algorithm for the hypercube in the presence of some faulty processors.

  13. 78 FR 7797 - Homeland Security Information Network Advisory Committee (HSINAC)

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-04

    ...DHS-2013-0005] Homeland Security Information Network Advisory Committee (HSINAC...SUMMARY: The Homeland Security Information Network Advisory Committee (HSIN...received by the (Homeland Security Information Network Advisory...

  14. A Software Architecture for Network Communication

    Microsoft Academic Search

    David P. Anderson

    1988-01-01

    A communication abstraction called real-time message streams (RMS) is proposed. An RMS is a simplex (unidirectional) stream with several performance and security parameters that express the needs of RMS clients and the capabilities of the RMS provider. RMS providers can eliminate unnecessary or redundant work and can optimally schedule resources; RMS clients can use the parameters to select optimal methods

  15. Satellite communications for the next generation telecommunication services and networks

    NASA Technical Reports Server (NTRS)

    Chitre, D. M.

    1991-01-01

    Satellite communications can play an important role in provisioning the next-generation telecommunication services and networks, provided the protocols specifying these services and networks are satellite-compatible and the satellite subnetworks, consisting of earth stations interconnected by the processor and the switch on board the satellite, interwork effectively with the terrestrial networks. The specific parameters and procedures of frame relay and broadband integrated services digital network (B-ISDN) protocols which are impacted by a satellite delay. Congestion and resource management functions for frame relay and B-ISDN are discussed in detail, describing the division of these functions between earth stations and on board the satellite. Specific onboard and ground functions are identified as potential candidates for their implementation via neural network technology.

  16. Communications performance of an undersea acoustic large-area network

    NASA Astrophysics Data System (ADS)

    Kriewaldt, Hannah A.; Rice, Joseph A.

    2005-04-01

    The U.S. Navy is developing Seaweb acoustic networking capability for integrating undersea systems. Seaweb architectures generally involve a wide-area network of fixed nodes consistent with future distributed autonomous sensors on the seafloor. Mobile nodes including autonomous undersea vehicles (AUVs) and submarines operate in the context of the grid by using the fixed nodes as both navigation reference points and communication access points. In October and November 2004, Theater Anti-Submarine Warfare Exercise (TASWEX04) showcased Seaweb in its first fleet appearance. This paper evaluates the TASWEX04 Seaweb performance in support of networked communications between a submarine and a surface ship. Considerations include physical-layer dependencies on the 9-14 kHz acoustic channel, such as refraction, wind-induced ambient noise, and submarine aspect angle. [Work supported by SSC San Diego.

  17. NASA Near Earth Network (NEN), Deep Space Network (DSN) and Space Network (SN) Support of CubeSat Communications

    NASA Technical Reports Server (NTRS)

    Schaire, Scott H.; Altunc, Serhat; Bussey, George; Shaw, Harry; Horne, Bill; Schier, Jim

    2015-01-01

    There has been a historical trend to increase capability and drive down the Size, Weight and Power (SWAP) of satellites and that trend continues today. Small satellites, including systems conforming to the CubeSat specification, because of their low launch and development costs, are enabling new concepts and capabilities for science investigations across multiple fields of interest to NASA. NASA scientists and engineers across many of NASAs Mission Directorates and Centers are developing exciting CubeSat concepts and welcome potential partnerships for CubeSat endeavors. From a communications and tracking point of view, small satellites including CubeSats are a challenge to coordinate because of existing small spacecraft constraints, such as limited SWAP and attitude control, low power, and the potential for high numbers of operational spacecraft. The NASA Space Communications and Navigation (SCaN) Programs Near Earth Network (NEN), Deep Space Network (DSN) and the Space Network (SN) are customer driven organizations that provide comprehensive communications services for space assets including data transport between a missions orbiting satellite and its Mission Operations Center (MOC). The NASA NEN consists of multiple ground antennas. The SN consists of a constellation of geosynchronous (Earth orbiting) relay satellites, named the Tracking and Data Relay Satellite System (TDRSS). The DSN currently makes available 13 antennas at its three tracking stations located around the world for interplanetary communication. The presentation will analyze how well these space communication networks are positioned to support the emerging small satellite and CubeSat market. Recognizing the potential support, the presentation will review the basic capabilities of the NEN, DSN and SN in the context of small satellites and will present information about NEN, DSN and SN-compatible flight radios and antenna development activities at the Goddard Space Flight Center (GSFC) and across industry. The presentation will review concepts on how the SN multiple access capability could help locate CubeSats and provide a low-latency early warning system. The presentation will also present how the DSN is evolving to maximize use of its assets for interplanetary CubeSats. The critical spectrum-related topics of available and appropriate frequency bands, licensing, and coordination will be reviewed. Other key considerations, such as standardization of radio frequency interfaces and flight and ground communications hardware systems, will be addressed as such standardization may reduce the amount of time and cost required to obtain frequency authorization and perform compatibility and end-to-end testing. Examples of standardization that exist today are the NASA NEN, DSN and SN systems which have published users guides and defined frequency bands for high data rate communication, as well as conformance to CCSDS standards. The workshop session will also seek input from the workshop participants to better understand the needs of small satellite systems and to identify key development activities and operational approaches necessary to enhance communication and navigation support using NASA's NEN, DSN and SN.

  18. A trade-off between information and communication in broadcast protocols

    Microsoft Academic Search

    Baruch Awerbuch; Oded Goldreich; Ronen Vainish; David Peleg

    1990-01-01

    This paper concerns the message complexity of broadcast in arbitrary point-to-point communication networks. Broadcast is a task initiated by a single processor that wishes to convey a message to all processors in the network. The widely accepted model of communication networks, in which each processor initially knows the identity of its neighbors but does not know the entire network topology,

  19. A Queueing Network Analysis of Computer Communication Networks with Window Flow Control

    Microsoft Academic Search

    MARTIN REISER

    1979-01-01

    A computer communication network with window flow control is modeled by a closed multichain queueing network. The severe computational limitation of previous solution algorithms is overcome with a heuristic derived from the recently found mean value analysis. A large numerical example is given.

  20. Informational benefits via knowledge networks among

    Microsoft Academic Search

    Claire Massey; Kate Lewis

    Purpose - This research aimed to obtain insights into how farmers on small and medium-sized farms perceived the benefits of the information they receive from their interpersonal networks and other sources. Design\\/methodology\\/approach - Farmers' information environments were explored using socio-spatial knowledge networks, diaries and in-depth interviews (to draw out participants' interpretations of significance). This enabled the perceived benefits of information