WorldWideScience

Sample records for automotive communication network

  1. Reliability in automotive ethernet networks

    DEFF Research Database (Denmark)

    Soares, Fabio L.; Campelo, Divanilson R.; Yan, Ying;

    2015-01-01

    This paper provides an overview of in-vehicle communication networks and addresses the challenges of providing reliability in automotive Ethernet in particular.......This paper provides an overview of in-vehicle communication networks and addresses the challenges of providing reliability in automotive Ethernet in particular....

  2. Automotive factory network renewal

    OpenAIRE

    Scicluna, Christopher

    2012-01-01

    The aim of this applied thesis was to plan, implement, and study the upgrading the network infrastructure in Valmet Automotive Oy, specifically in its Uusikaupunki factory. Valmet Automotive is a Finnish automotive service provider, focusing on premium vehicles, convertible roof systems and electric vehicles. The objective was to plan and implement a networking infrastructure that could support the load of a factory in full-scale production, while ensuring near-constant availability. T...

  3. Automotive mechatronics automotive networking, driving stability systems, electronics

    CERN Document Server

    2015-01-01

    As the complexity of automotive vehicles increases this book presents operational and practical issues of automotive mechatronics. It is a comprehensive introduction to controlled automotive systems and provides detailed information of sensors for travel, angle, engine speed, vehicle speed, acceleration, pressure, temperature, flow, gas concentration etc. The measurement principles of the different sensor groups are explained and examples to show the measurement principles applied in different types. Contents Basics of mechatronics.- Architecture.- Electronic control unit.- Software development.- Basic principles of networking.- Automotive networking.- Bus systems.- Automotive sensors.- Sensor measuring principles.- Sensor types.- Electric actuators.- Electrohydraulic actuators.- Electronic transmission control.- Electronic transmission control unit.- Modules for transmission control.- Antilock braking system.- Traction control system.- Electronic stability program.- Automatic brake functions.- Hydraulic modu...

  4. The Realistic Mobility Evaluation of Vehicular Ad-Hoc Network for Indian Automotive Networks

    Directory of Open Access Journals (Sweden)

    V.S.Dhaka

    2014-04-01

    Full Text Available In recent years, continuous progress in wireless communication has opened a new research field in computer networks. Now a day’s wireless ad-hoc networking is an emerging research technology that needs attention of the industry people and the academicians. A vehicular ad-hoc network uses vehicles as mobile nodes to create mobility in a network. It’s a challenge to generate realistic mobility for Indian networks as no TIGER or Shapefile map is available for Indian Automotive Networks. This paper simulates the realistic mobility of the Vehicular Ad-hoc Networks (VANETs. The key feature of this work is the realistic mobility generation for the Indian Automotive Intelligent Transport System (ITS and also to analyze the throughput, packet delivery fraction (PDF and packet loss for realistic scenario. The experimental analysis helps in providing effective communication for safety to the driver and passengers.

  5. A Secure Mechanism to Supervise Automotive Sensor Network by Client on Smart Phone

    Directory of Open Access Journals (Sweden)

    T R Yashavanth

    2013-03-01

    Full Text Available This paper presents a proposal on design of a secure client on smart phone to monitor automotive sensor network. Recently, more and more vehicles, such as BMW X5, are connected from outside via smart phone [3]. From smart phone, users can use the internet resources in automotive. Users can monitor the automotives by using their smart phones. When the automotive is moving or stolen by robber, alert information will be reported to users and users can even brake their automotive via smart phone in emergency status by sending control command to the vehicle information gateway. So client software in smart phone is required to monitor the sensor network in automotives. In order to prevent malicious attack on the client software by malicious attackers which are usually the robbers, there should be a mechanism provided to the clients which offers security by considering few criteria’s like power of computation, level of security and consumption of power. This proposed method uses IDEA for the encryption of all the messages since IDEA has high level of security and suitable to implement in software and also demands on computational power is less. Record management set is being suggested for the storage of critical data which is a Java MIDlet based mechanism. Between client software and its gateway a communication management on transaction is also proposed. The verification of the key updating process is verified with model checking in UPPAAL [7].

  6. Hybrid Modeling and Simulation of Automotive Supply Chain Network

    Directory of Open Access Journals (Sweden)

    Wen Wang

    2013-07-01

    Full Text Available According to the operation of automotive supply chain and the features of various simulation methods, we create and simulate a automotive supply chain network model with the core enterprise of two vehicle manufacturers, consisting of several parts suppliers, vehicle distributors and logistics service providers. On this basis of a conceptual model including the establishment of enterprise layer, business layer and operation layer, we establish a detailed model of the network system according to the network structure of automotive supply chain, the operation process and the internal business process of core enterprises; then we use System Dynamics (SD, Discrete Event Simulation (DES and Agent Based Modeling (ABM to describe the operating state of each node in the network model. We execute and analyze the simulation model of the whole network system described by Anylogic, using the results of the distributors’ inventory, inventory cost and customer’s satisfaction to prove the effectiveness of the model.

  7. The application of network communication technology in automotive electronics%汽车电子网络通信技术的应用

    Institute of Scientific and Technical Information of China (English)

    陈益庆

    2015-01-01

    With the development of modern science and technology progress, the car has to the Internet, wireless connection, personal communications electronics, entertainment equipment integration, constantly satisfy the people to the automobile performance, safety, comfort, fuel economy requirements. The use of a large number of equipment, the control of complex wiring, convenient and simple, safe and reliable control demand is driving change and development of automobile electronic network technology, entering the era of electronic networks.%随着现代科技的发展进步,汽车已将网际网路、无线连接、个人通信电子装置、娱乐设备等整合于一身,不断满足着人们对汽车动力性、安全性、舒适性、经济性的要求。大量设备的使用、繁琐的控制布线,方便简洁、安全可靠的控制需求促使汽车电子网络技术的变革与发展,迈入电子网络时代。

  8. Multimedia communications and networking

    CERN Document Server

    da Silva, Mario Marques

    2012-01-01

    The result of decades of research and international project experience, Multimedia Communications and Networking provides authoritative insight into recent developments in multimedia, digital communications, and networking services and technologies. Supplying you with the required foundation in these areas, it illustrates the means that will allow for improved digital communications and networks. The book starts with a review of the fundamental concepts, requirements, and constraints in networks and telecommunications. It describes channel disturbances that can hinder system performance--inclu

  9. Bosch automotive electrics and automotive electronics systems and components, networking and hybrid drive

    CERN Document Server

    2014-01-01

    The significance of electrical and electronic systems has increased considerably in the last few years and this trend is set to continue. The characteristics feature of innovative systems is the fact that they can work together in a network. This requires powerful bus systems that the electronic control units can use to exchange information. Networking and the various bus systems used in motor vehicles are the prominent new topic in the 5th edition of the "Automotive Electric, Automotive Electronics" technical manual. The existing chapters have also been updated, so that this new edition brings the reader up to date on the subjects of electrical and electronic systems in the motor vehicle. Content Electrical and electronical systems – Basic principles of networking - Examples of networked vehicles – Bus systems – Architecture of electronic systems – Mechatronics – Elektronics – Electronic control Units – Software – Sensors – Actuators – Hybrid drives – Vehicle electrical system – Start...

  10. Computer-communication networks

    CERN Document Server

    Meditch, James S

    1983-01-01

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

  11. Designing for Networked Communications

    DEFF Research Database (Denmark)

    Designing for Networked Communications: Strategies and Development explains how to plan, use, and understand the products and the dynamic social processes and tasks some of the most vital innovations in the knowledge society depend upon– social as well as technological. Focusing on various forms...... of design, implementation and integration of computer mediated communication, this book bridges the academic fields of computer science and communication studies. Designing for Networked Communications: Strategies and Development uses an interdisciplinary approach, and presents results from recent...... and important research in a variety of forms for networked communications. A constructive and critical view of the interplay between the new electronic and the more conventional modes of communication are utilized, while studies of organizational work practices demonstrate that the use of new technologies...

  12. Data communications and computer communications network

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jang Gwon; Gu, Chang Hoe

    2005-03-15

    This textbook is composed of twelve chapters, which are communication network introduction, foundation of data communication, data link control, circuit switching system, packet switching system, multiple access communication system, protocol and architecture, LAN, MAN communication network, integrated service digital network, internet and Asymmetric digital subscriber Line and Wireless Local Loop. Each chapter has the introduction of the technique, structure, function and practice problems. It also has the appendix on electricity and communication standards organization, characteristic table and glossary.

  13. Data communications and computer communications network

    International Nuclear Information System (INIS)

    This textbook is composed of twelve chapters, which are communication network introduction, foundation of data communication, data link control, circuit switching system, packet switching system, multiple access communication system, protocol and architecture, LAN, MAN communication network, integrated service digital network, internet and Asymmetric digital subscriber Line and Wireless Local Loop. Each chapter has the introduction of the technique, structure, function and practice problems. It also has the appendix on electricity and communication standards organization, characteristic table and glossary.

  14. Communication Network Analysis Methods.

    Science.gov (United States)

    Farace, Richard V.; Mabee, Timothy

    This paper reviews a variety of analytic procedures that can be applied to network data, discussing the assumptions and usefulness of each procedure when applied to the complexity of human communication. Special attention is paid to the network properties measured or implied by each procedure. Factor analysis and multidimensional scaling are among…

  15. NASA Communications Augmentation network

    Science.gov (United States)

    Omidyar, Guy C.; Butler, Thomas E.; Laios, Straton C.

    1990-09-01

    The NASA Communications (Nascom) Division of the Mission Operations and Data Systems Directorate (MO&DSD) is to undertake a major initiative to develop the Nascom Augmentation (NAUG) network to achieve its long-range service objectives for operational data transport to support the Space Station Freedom Program, the Earth Observing System (EOS), and other projects. The NAUG is the Nascom ground communications network being developed to accommodate the operational traffic of the mid-1990s and beyond. The NAUG network development will be based on the Open Systems Interconnection Reference Model (OSI-RM). This paper describes the NAUG network architecture, subsystems, topology, and services; addresses issues of internetworking the Nascom network with other elements of the Space Station Information System (SSIS); discusses the operations environment. This paper also notes the areas of related research and presents the current conception of how the network will provide broadband services in 1998.

  16. Introduction to communication networks

    CERN Document Server

    Anttalainen, Tarmo

    2014-01-01

    This new book is an introduction to modern communications networks that now rely far less on telephone services and more on cellular and IP networks. The resource is designed to provide answers to the fundamental questions concerning telecommunications networks and services. This includes the structure and main components of a modern telecommunications network; the importance of standardization; and how cellular mobile networks operate; among many others. In addition, you are provided with problems and review questions to work though and help you master the material.

  17. Hyperswitch Communication Network Computer

    Science.gov (United States)

    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.

  18. European environmental communication networks

    International Nuclear Information System (INIS)

    The goal of this presentation is apprise of special community - representatives of state and public administration, self-administration, workers of scientific institutes, schools, private companies and next privies subjects of areas of the environment with possibilities of access to actual environmental information by the Internet. Web-sites of environmental communication networks with data about the environment are presented

  19. A Secure Mechanism to Supervise Automotive Sensor Network by Client on Smart Phone

    OpenAIRE

    T R Yashavanth,; Ravi S Malashetty,; V R Udupi

    2013-01-01

    This paper presents a proposal on design of a secure client on smart phone to monitor automotive sensor network. Recently, more and more vehicles, such as BMW X5, are connected from outside via smart phone [3]. From smart phone, users can use the internet resources in automotive. Users can monitor the automotives by using their smart phones. When the automotive is moving or stolen by robber, alert information will be reported to users and users can even brake their automotive via smart phone ...

  20. A Multiobjective Optimization Model in Automotive Supply Chain Networks

    Directory of Open Access Journals (Sweden)

    Abdolhossein Sadrnia

    2013-01-01

    Full Text Available In the new decade, green investment decisions are attracting more interest in design supply chains due to the hidden economic benefits and environmental legislative barriers. In this paper, a supply chain network design problem with both economic and environmental concerns is presented. Therefore, a multiobjective optimization model that captures the trade-off between the total logistics cost and CO2 emissions is proposed. With regard to the complexity of logistic networks, a new multiobjective swarm intelligence algorithm known as a multiobjective Gravitational search algorithm (MOGSA has been implemented for solving the proposed mathematical model. To evaluate the effectiveness of the model, a comprehensive set of numerical experiments is explained. The results obtained show that the proposed model can be applied as an effective tool in strategic planning for optimizing cost and CO2 emissions in an environmentally friendly automotive supply chain.

  1. Industrial Upgrading in Global Production Networks: The Case of the Chinese Automotive Industry

    OpenAIRE

    Li, Yansheng; Xin Xin KONG; Zhang, Miao

    2015-01-01

    This article examines the development of China’s automotive industry. The evidence shows that integration in global production networks has stimulated upgrading of technological capabilities among automotive firms. However, the competitiveness and intra-industry analyses show mixed results. Although intraindustry trade in automotive products has improved since 2000, the trade competitiveness of completely built up vehicles has largely remained in low value added activities. Nevertheless, firm...

  2. Marketing Communication in Social Networks

    OpenAIRE

    Spěváková, Kristýna

    2011-01-01

    Title of this thesis is Possibilities of marketing communication in social networks. In the theoretical part of this thesis are explained fundamentals of marketing, of marketing communication and its possibilities with focus on social networks. Further this thesis describes basics of several social networks and the way they work. The biggest part of the theoretical presumptions is devoted to communication mix and its tools, which are recommended to be used for good performing marketing commu...

  3. SOCIAL NETWORKS AND INTERPERSONAL COMMUNICATION

    Directory of Open Access Journals (Sweden)

    Veronica GHEORGHIȚĂ

    2014-11-01

    Full Text Available Social networks visible influence people's ability to interact and communicate. Extending social circles by establishing virtual links involves a number of positive aspects such as: instant access to options for interaction, sharing of information to large communities of people, intensification of acts of communication, high levels of feedback and trust with people with whom we communicate. On the other hand, social networks adversely affects communication by decreasing the interaction face to face, by imposing superficial communications experiences, grammatical and spelling erosion of the language. Therefore, the study aims to capture the spread of social networks, their use and impact on interpersonal communication. More specifically, they look for the answer to the question: what is the nature of interpersonal communication that is found on social networking sites: personal, emotional, private or shared, informal, and public?

  4. The persistent heterogeneity of trade patterns: A comparison of four European Automotive Global Production Networks

    OpenAIRE

    Vincent FRIGANT (E3i-IFReDE-GRES); Zumpe, Martin

    2014-01-01

    In this paper, we examine the structure and the evolution of international exchanges of auto parts over the 2000-2012 period for four European countries. The first part of our study reviews the literature and points out four stylized facts about the geography of automotive supply networks. In section 2 we propose an analysis of the organisation of automotive supply chains based on the global production networks framework. We give details about this approach by stating the nature of trade flow...

  5. Securing underwater wireless communication networks

    OpenAIRE

    Domingo Aladrén, Mari Carmen

    2011-01-01

    Underwater wireless communication networks are particularly vulnerable to malicious attacks due to the high bit error rates, large and variable propagation delays, and low bandwidth of acoustic channels. The unique characteristics of the underwater acoustic communication channel, and the differences between underwater sensor networks and their ground-based counterparts require the development of efficient and reliable security mechanisms. In this article, a compl...

  6. Speech Communication and Telephone Networks

    Science.gov (United States)

    Gierlich, H. W.

    Speech communication over telephone networks has one major constraint: The communication has to be “real time”. The basic principle since the beginning of all telephone networks has been to provide a communication system capable of substituting the air path between two persons having a conversation at 1-m distance. This is the so-called orthotelephonic reference position [7]. Although many technical compromises must be made to enable worldwide communication over telephone networks, it is still the goal to achieve speech quality performance which is close to this reference.

  7. Topological Rankings in Communication Networks

    DEFF Research Database (Denmark)

    Aabrandt, Andreas; Hansen, Vagn Lundsgaard; Træholt, Chresten

    2015-01-01

    In the theory of communication the central problem is to study how agents exchange information. This problem may be studied using the theory of connected spaces in topology, since a communication network can be modelled as a topological space such that agents can communicate if and only...... if they belong to the same path connected component of that space. In order to study combinatorial properties of such a communication network, notions from algebraic topology are applied. This makes it possible to determine the shape of a network by concrete invariants, e.g. the number of connected components....... Elements of a network may then be ranked according to how essential their positions are in the network by considering the effect of removing them. Defining a ranking of a network which takes the individual position of each entity into account has the purpose of assigning different roles to the entities, e...

  8. V2V Communication Survey - (Wireless Technology

    Directory of Open Access Journals (Sweden)

    Vaishali D. Khairnar

    2012-01-01

    Full Text Available This paper presents the specific application of wireless communication, Automotive Wireless Communication_ also called as Vehicle-to-Vehicle Communication. The paper first gives an introduction to the Automotive Wireless Communication. It explains the technology used for Automotive Wireless Communication along with the various automotive applications relying on wireless communication. Automotive Wireless Communication gives drivers a sixth sense to know what’s going on around them to help avoid accidents and improve traffic flow. The paper also describes VANETS (vehicular ad hoc networks and Real-world test network implementation. Finally, the paper is summarized.

  9. MIMO Communication for Cellular Networks

    CERN Document Server

    Huang, Howard; Venkatesan, Sivarama

    2012-01-01

    As the theoretical foundations of multiple-antenna techniques evolve and as these multiple-input multiple-output (MIMO) techniques become essential for providing high data rates in wireless systems, there is a growing need to understand the performance limits of MIMO in practical networks. To address this need, MIMO Communication for Cellular Networks presents a systematic description of MIMO technology classes and a framework for MIMO system design that takes into account the essential physical-layer features of practical cellular networks. In contrast to works that focus on the theoretical performance of abstract MIMO channels, MIMO Communication for Cellular Networks emphasizes the practical performance of realistic MIMO systems. A unified set of system simulation results highlights relative performance gains of different MIMO techniques and provides insights into how best to use multiple antennas in cellular networks under various conditions. MIMO Communication for Cellular Networks describes single-user,...

  10. Emerging trends in communication networks

    CERN Document Server

    Hasan, Syed Faraz

    2014-01-01

    This book covers the state of the art in communication networks with the help of illustrative diagrams and recent references published in reputed journals and magazines. The book gives readers a glimpse into the next generation of communication networks. It explores topics that are currently in the research phase and/or are expected to be deployed in recent future such as LTE networks and IPv6 networks. This book is written for students/researchers who wish to come up to date with the recent trends in telecommunications.

  11. Performance measurement of the after-sales service network: Evidence from the automotive industry

    OpenAIRE

    Shahnoush Shahrouzi Fard; Seyed Mehdi Hosseini

    2015-01-01

    This paper presents an empirical investigation to determine important factors influencing on customer satisfaction in after-sales service network of automotive industry. The study designs two questionnaires, one for measuring the quality of after-sales services and the other for measuring customers’ satisfaction. The study selects a sample of 265 randomly selected customers out of 850 people who received the services from an automotive firm in Iran. Cronbach alpha has calculated as 0.82, whic...

  12. Computation and Communication Evaluation of an Authentication Mechanism for Time-Triggered Networked Control Systems.

    Science.gov (United States)

    Martins, Goncalo; Moondra, Arul; Dubey, Abhishek; Bhattacharjee, Anirban; Koutsoukos, Xenofon D

    2016-01-01

    In modern networked control applications, confidentiality and integrity are important features to address in order to prevent against attacks. Moreover, network control systems are a fundamental part of the communication components of current cyber-physical systems (e.g., automotive communications). Many networked control systems employ Time-Triggered (TT) architectures that provide mechanisms enabling the exchange of precise and synchronous messages. TT systems have computation and communication constraints, and with the aim to enable secure communications in the network, it is important to evaluate the computational and communication overhead of implementing secure communication mechanisms. This paper presents a comprehensive analysis and evaluation of the effects of adding a Hash-based Message Authentication (HMAC) to TT networked control systems. The contributions of the paper include (1) the analysis and experimental validation of the communication overhead, as well as a scalability analysis that utilizes the experimental result for both wired and wireless platforms and (2) an experimental evaluation of the computational overhead of HMAC based on a kernel-level Linux implementation. An automotive application is used as an example, and the results show that it is feasible to implement a secure communication mechanism without interfering with the existing automotive controller execution times. The methods and results of the paper can be used for evaluating the performance impact of security mechanisms and, thus, for the design of secure wired and wireless TT networked control systems. PMID:27463718

  13. Computation and Communication Evaluation of an Authentication Mechanism for Time-Triggered Networked Control Systems.

    Science.gov (United States)

    Martins, Goncalo; Moondra, Arul; Dubey, Abhishek; Bhattacharjee, Anirban; Koutsoukos, Xenofon D

    2016-07-25

    In modern networked control applications, confidentiality and integrity are important features to address in order to prevent against attacks. Moreover, network control systems are a fundamental part of the communication components of current cyber-physical systems (e.g., automotive communications). Many networked control systems employ Time-Triggered (TT) architectures that provide mechanisms enabling the exchange of precise and synchronous messages. TT systems have computation and communication constraints, and with the aim to enable secure communications in the network, it is important to evaluate the computational and communication overhead of implementing secure communication mechanisms. This paper presents a comprehensive analysis and evaluation of the effects of adding a Hash-based Message Authentication (HMAC) to TT networked control systems. The contributions of the paper include (1) the analysis and experimental validation of the communication overhead, as well as a scalability analysis that utilizes the experimental result for both wired and wireless platforms and (2) an experimental evaluation of the computational overhead of HMAC based on a kernel-level Linux implementation. An automotive application is used as an example, and the results show that it is feasible to implement a secure communication mechanism without interfering with the existing automotive controller execution times. The methods and results of the paper can be used for evaluating the performance impact of security mechanisms and, thus, for the design of secure wired and wireless TT networked control systems.

  14. Computation and Communication Evaluation of an Authentication Mechanism for Time-Triggered Networked Control Systems

    Science.gov (United States)

    Martins, Goncalo; Moondra, Arul; Dubey, Abhishek; Bhattacharjee, Anirban; Koutsoukos, Xenofon D.

    2016-01-01

    In modern networked control applications, confidentiality and integrity are important features to address in order to prevent against attacks. Moreover, network control systems are a fundamental part of the communication components of current cyber-physical systems (e.g., automotive communications). Many networked control systems employ Time-Triggered (TT) architectures that provide mechanisms enabling the exchange of precise and synchronous messages. TT systems have computation and communication constraints, and with the aim to enable secure communications in the network, it is important to evaluate the computational and communication overhead of implementing secure communication mechanisms. This paper presents a comprehensive analysis and evaluation of the effects of adding a Hash-based Message Authentication (HMAC) to TT networked control systems. The contributions of the paper include (1) the analysis and experimental validation of the communication overhead, as well as a scalability analysis that utilizes the experimental result for both wired and wireless platforms and (2) an experimental evaluation of the computational overhead of HMAC based on a kernel-level Linux implementation. An automotive application is used as an example, and the results show that it is feasible to implement a secure communication mechanism without interfering with the existing automotive controller execution times. The methods and results of the paper can be used for evaluating the performance impact of security mechanisms and, thus, for the design of secure wired and wireless TT networked control systems. PMID:27463718

  15. Ergodicity of conservative communication networks

    OpenAIRE

    Botvich, Dmitri D.; Zamyatin, A. A.

    1992-01-01

    Projet MEVAL We analyze a communication network with several types of calls. For a wide class of conservative service disciplines, we give ergodicity criteria. Exponentially fast convergence to steady state is also proved.

  16. BRAND COMMUNICATION ON SOCIAL NETWORKS

    Directory of Open Access Journals (Sweden)

    Otilia-Elena PLATON

    2015-07-01

    Full Text Available The communication represents a basic element for the marketing activity that helps companies to achieve their objectives. Building long-term relationships between brands and consumers is one of the most important objectives pursued by marketers. This involves brand communication and creating multiple connections with consumers, even in the online environment. From this point of view, social networks proved to be an effective way of linking brands and consumers online. This paper aims to present some aspects involved by the usage of social networks in brand communication by analyzing several examples of online marketing campaigns implemented on Facebook on the occasion of Valentine's Day by six different brands.

  17. Fourth international conference on Networks & Communications

    CERN Document Server

    Meghanathan, Natarajan; Nagamalai, Dhinaharan; Computer Networks & Communications (NetCom)

    2013-01-01

    Computer Networks & Communications (NetCom) is the proceedings from the Fourth International Conference on Networks & Communications. This book covers theory, methodology and applications of computer networks, network protocols and wireless networks, data communication technologies, and network security. The proceedings will feature peer-reviewed papers that illustrate research results, projects, surveys and industrial experiences that describe significant advances in the diverse areas of computer networks & communications.

  18. Communicating embedded systems networks applications

    CERN Document Server

    Krief, Francine

    2013-01-01

    Embedded systems become more and more complex and require having some knowledge in various disciplines such as electronics, data processing, telecommunications and networks. Without detailing all the aspects related to the design of embedded systems, this book, which was written by specialists in electronics, data processing and telecommunications and networks, gives an interesting point of view of communication techniques and problems in embedded systems. This choice is easily justified by the fact that embedded systems are today massively communicating and that telecommunications and network

  19. NASA Integrated Space Communications Network

    Science.gov (United States)

    Tai, Wallace; Wright, Nate; Prior, Mike; Bhasin, Kul

    2012-01-01

    The NASA Integrated Network for Space Communications and Navigation (SCaN) has been in the definition phase since 2010. It is intended to integrate NASA s three existing network elements, i.e., the Space Network, Near Earth Network, and Deep Space Network, into a single network. In addition to the technical merits, the primary purpose of the Integrated Network is to achieve a level of operating cost efficiency significantly higher than it is today. Salient features of the Integrated Network include (a) a central system element that performs service management functions and user mission interfaces for service requests; (b) a set of common service execution equipment deployed at the all stations that provides return, forward, and radiometric data processing and delivery capabilities; (c) the network monitor and control operations for the entire integrated network are conducted remotely and centrally at a prime-shift site and rotating among three sites globally (a follow-the-sun approach); (d) the common network monitor and control software deployed at all three network elements that supports the follow-the-sun operations.

  20. Underwater optical wireless communication network

    Science.gov (United States)

    Arnon, Shlomi

    2010-01-01

    The growing need for underwater observation and subsea monitoring systems has stimulated considerable interest in advancing the enabling technologies of underwater wireless communication and underwater sensor networks. This communication technology is expected to play an important role in investigating climate change, in monitoring biological, biogeochemical, evolutionary, and ecological changes in the sea, ocean, and lake environments, and in helping to control and maintain oil production facilities and harbors using unmanned underwater vehicles (UUVs), submarines, ships, buoys, and divers. However, the present technology of underwater acoustic communication cannot provide the high data rate required to investigate and monitor these environments and facilities. Optical wireless communication has been proposed as the best alternative to meet this challenge. Models are presented for three kinds of optical wireless communication links: (a) a line-of-sight link, (b) a modulating retroreflector link, and (c) a reflective link, all of which can provide the required data rate. We analyze the link performance based on these models. From the analysis, it is clear that as the water absorption increases, the communication performance decreases dramatically for the three link types. However, by using the scattered light it was possible to mitigate this decrease in some cases. It is concluded from the analysis that a high-data-rate underwater optical wireless network is a feasible solution for emerging applications such as UUV-to-UUV links and networks of sensors, and extended ranges in these applications could be achieved by applying a multi-hop concept.

  1. Distributed beamforming in man portable communication networks

    OpenAIRE

    Chan, Chun Man

    2007-01-01

    The advancement in communication and networking technologies lead to the emergence of network centric systems adopted by military forces. Many military forces around the world are equipping their ground soldiers with "man portable" or "mobile" wireless communication devices to form a local communication network as part of the overarching communication network for information warfare. In a non-line of sight environment, the devices' communication range to the base station degrades signific...

  2. Multiple-Ring Digital Communication Network

    Science.gov (United States)

    Kirkham, Harold

    1992-01-01

    Optical-fiber digital communication network to support data-acquisition and control functions of electric-power-distribution networks. Optical-fiber links of communication network follow power-distribution routes. Since fiber crosses open power switches, communication network includes multiple interconnected loops with occasional spurs. At each intersection node is needed. Nodes of communication network include power-distribution substations and power-controlling units. In addition to serving data acquisition and control functions, each node acts as repeater, passing on messages to next node(s). Multiple-ring communication network operates on new AbNET protocol and features fiber-optic communication.

  3. Network-Centric Quantum Communications

    Science.gov (United States)

    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.

  4. Fifth International Conference on Networks & Communications

    CERN Document Server

    Nagamalai, Dhinaharan; Rajasekaran, Sanguthevar

    2014-01-01

    This book covers theory, methodology and applications of computer networks, network protocols and wireless networks, data communication technologies, and network security. The book is based on the proceedings from the Fifth International Conference on Networks & Communications (NetCom). The proceedings will feature peer-reviewed papers that illustrate research results, projects, surveys and industrial experiences that describe significant advances in the diverse areas of computer networks & communications.

  5. Global production networks and local suppliers: Sonora’s entrepreneurs facing automotive expansion growth

    Directory of Open Access Journals (Sweden)

    Álvaro Bracamonte Sierra

    2008-07-01

    Full Text Available Within the context of the severe crisis faced by the U.S. based automotive firms, one of their strategies has been the relocation of the assembly plants in Mexico. This article analyzes the case of the automotive cluster led by Ford in Hermosillo, in the Mexican state of Sonora, showing that this type of clusters led by transnational corporations create technological spillovers and stimulate the accumulation of local capabilities. Particular attention is given to the process of creation of local small and medium enterprises linked to global production networks.

  6. Using networking and communications software in business

    CERN Document Server

    McBride, PK

    2014-01-01

    Using Networking and Communications Software in Business covers the importance of networks in a business firm, the benefits of computer communications within a firm, and the cost-benefit in putting up networks in businesses. The book is divided into six parts. Part I looks into the nature and varieties of networks, networking standards, and network software. Part II discusses the planning of a networked system, which includes analyzing the requirements for the network system, the hardware for the network, and network management. The installation of the network system and the network managemen

  7. Applied data communications and networks

    CERN Document Server

    Buchanan, W

    1996-01-01

    The usage of data communications and computer networks are ever in­ creasing. It is one of the few technological areas which brings benefits to most of the countries and the peoples of the world. Without it many industries could not exist. It is the objective of this book to discuss data communications in a readable form that students and professionals all over the world can understand. As much as possible the text uses dia­ grams to illustrate key points. Most currently available data communications books take their view­ point from either a computer scientists top-down approach or from an electronic engineers bottom-up approach. This book takes a practical ap­ proach and supports it with a theoretical background to create a textbook which can be used by electronic engineers, computer engineers, computer scientists and industry professionals. It discusses most of the current and future key data communications technologies, including: • Data Communications Standards and Models; • Local Area Networks (...

  8. Communications in interference limited networks

    CERN Document Server

    2016-01-01

    This book offers means to handle interference as a central problem of operating wireless networks. It investigates centralized and decentralized methods to avoid and handle interference as well as approaches that resolve interference constructively. The latter type of approach tries to solve the joint detection and estimation problem of several data streams that share a common medium. In fact, an exciting insight into the operation of networks is that it may be beneficial, in terms of an overall throughput, to actively create and manage interference. Thus, when handled properly, "mixing" of data in networks becomes a useful tool of operation rather than the nuisance as which it has been treated traditionally. With the development of mobile, robust, ubiquitous, reliable and instantaneous communication being a driving and enabling factor of an information centric economy, the understanding, mitigation and exploitation of interference in networks must be seen as a centrally important task.

  9. Information communication on complex networks

    International Nuclear Information System (INIS)

    Since communication networks such as the Internet, which is regarded as a complex network, have recently become a huge scale and a lot of data pass through them, the improvement of packet routing strategies for transport is one of the most significant themes in the study of computer networks. It is especially important to find routing strategies which can bear as many traffic as possible without congestion in complex networks. First, using neural networks, we introduce a strategy for packet routing on complex networks, where path lengths and queue lengths in nodes are taken into account within a framework of statistical physics. Secondly, instead of using shortest paths, we propose efficient paths which avoid hubs, nodes with a great many degrees, on scale-free networks with a weight of each node. We improve the heuristic algorithm proposed by Danila et. al. which optimizes step by step routing properties on congestion by using the information of betweenness, the probability of paths passing through a node in all optimal paths which are defined according to a rule, and mitigates the congestion. We confirm the new heuristic algorithm which balances traffic on networks by achieving minimization of the maximum betweenness in much smaller number of iteration steps. Finally, We model virus spreading and data transfer on peer-to-peer (P2P) networks. Using mean-field approximation, we obtain an analytical formulation and emulate virus spreading on the network and compare the results with those of simulation. Moreover, we investigate the mitigation of information traffic congestion in the P2P networks.

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

    Science.gov (United States)

    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.

  11. Supplier Networks and the Importance of Information Technology: Outlook on the European Automotive Industry

    Science.gov (United States)

    Gil, Maria José Alvarez; Kulcsar, Borbala; Aksoy, Dilan

    The trends in the automotive industry changed radically from the beginning of the 80s. Increasing competition, new systems and developments compelled the companies to re-evaluate and re-design their investments and processes, by extending their networks to other parts of the world in order to gain more market. This trend could be observed first in the Western-European countries and later in Eastern-Europe. With entering new areas the companies had to face with several difficulties coming inter alia from the decisions of supplier network and information system implementation. In our study we analyze the strategic decisions of major carmaker companies entering the Eastern-European market. Our research includes two case studies of the Hungarian automotive sector.

  12. A distribution network design problem in the automotive industry: MIP formulation and heuristics

    OpenAIRE

    Kchaou Boujelben, Mouna; Gicquel, Céline; Minoux, Michel

    2014-01-01

    International audience We consider a multi-product distribution network design problem arising from a case-study in the automotive industry. Based on the realistic assumptions, we introduce minimum volume, maximum covering distance and single sourcing constraints, making the problem difficult to solve for large-size instances. We thus develop several heuristic procedures using various relaxations of the original MIP formulation of the problem. In our numerical experiments, we analyze the s...

  13. Innovation and Specialization Dynamics in the Automotive Sector: Comparative Analysis of Cooperation & Application Networks

    OpenAIRE

    Oliver Emons

    2010-01-01

    This paper considers the innovation dynamics in the automotive industry of selected countries. Key elements concern the intensity of patenting networks. The role of innovation dynamics differs across countries which can be explained in terms of headquarter status, the vertical integration of the sector and the overall structural adjustment. A better regional R&D activity tends to stimulate regional economic development. In this context, clusters become more important, because these constructs...

  14. PIPELINES AS COMMUNICATION NETWORK LINKS

    Energy Technology Data Exchange (ETDEWEB)

    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.

  15. The Structure of Online Consumer Communication Networks

    NARCIS (Netherlands)

    B.G.C. Dellaert (Benedict); M.J.W. Harmsen-van Hout (Marjolein); P.J.J. Herings (Jean-Jacques)

    2006-01-01

    textabstractIn this paper we study the structure of the bilateral communication links within Online Consumer Communication Networks (OCCNs), such as virtual communities. Compared to the offline world, consumers in online networks are highly flexible to choose their communication partners and little

  16. Modeling GSM Based Network Communication in Vehicular Network

    OpenAIRE

    M. Milton Joe; Ramakrishnan, B.; R. S. Shaji

    2014-01-01

    Obviously fair communication establishment in every technology increases the efficiency. As we know well, vehicles are used in day to day life of every human being to move from one location to another location. If network communication is formed between vehicles, mobile phones and home based telephones, it will increase the safety of the passengers by communicating with one another. In this paper, we propose GSM based network communication in vehicles, which will develop reliable network comm...

  17. Terminal-oriented computer-communication networks.

    Science.gov (United States)

    Schwartz, M.; Boorstyn, R. R.; Pickholtz, R. L.

    1972-01-01

    Four examples of currently operating computer-communication networks are described in this tutorial paper. They include the TYMNET network, the GE Information Services network, the NASDAQ over-the-counter stock-quotation system, and the Computer Sciences Infonet. These networks all use programmable concentrators for combining a multiplicity of terminals. Included in the discussion for each network is a description of the overall network structure, the handling and transmission of messages, communication requirements, routing and reliability consideration where applicable, operating data and design specifications where available, and unique design features in the area of computer communications.

  18. Wireless communications networks for the smart grid

    CERN Document Server

    Ho, Quang-Dung; Rajalingham, Gowdemy; Le-Ngoc, Tho

    2014-01-01

    This brief presents a comprehensive review of the network architecture and communication technologies of the smart grid communication network (SGCN). It then studies the strengths, weaknesses and applications of two promising wireless mesh routing protocols that could be used to implement the SGCN. Packet transmission reliability, latency and robustness of these two protocols are evaluated and compared by simulations in various practical SGCN scenarios. Finally, technical challenges and open research opportunities of the SGCN are addressed. Wireless Communications Networks for Smart Grid provi

  19. societal impact of electronic communication networks

    OpenAIRE

    Gremont, Boris

    2012-01-01

    The talk provides an overview of the present and future of electronic communication networks. Starting from the creation of the computer, key concepts pertaining to the scientific and technological development of electronic communication networks will be introduced and discussed in terms of their positive and sustained impact for society. Current trends and shortcomings will also be discussed. With the increasing reliance of future societies on communication networks, the need for improved sy...

  20. Maritime wideband communication networks video transmission scheduling

    CERN Document Server

    Yang, Tingting

    2014-01-01

    This Springer Brief covers emerging maritime wideband communication networks and how they facilitate applications such as maritime distress, urgency, safety and general communications. It provides valuable insight on the data transmission scheduling and protocol design for the maritime wideband network. This brief begins with an introduction to maritime wideband communication networks including the architecture, framework, operations and a comprehensive survey on current developments. The second part of the brief presents the resource allocation and scheduling for video packet transmission wit

  1. Improving stakeholder communication in a network organization

    OpenAIRE

    Sisättö, Satu

    2016-01-01

    This thesis focuses on the stakeholder communication of the Team Finland network. The stakeholder group in this research is the Finnish small and medium-sized enterprises (SMEs) seeking internationalization. The chosen channel is newsletter. This thesis comprehends Team Finland network as an organization, and therefore does not focus on the stakeholder communication of the different network organizations. As this is a commissioned research, the thesis does not focus on other communication cha...

  2. Social networks: communication and change

    Directory of Open Access Journals (Sweden)

    Gustavo Cardoso

    2011-01-01

    Full Text Available Virtual social networks have brought about the possibility for open and plural debate, where all those with the necessary literacy skills and means are able to participate in the creation and dissemination of information. By pressing political agents and determining the “agenda” of a lot of the media, users demonstrate that we stand at an ideal platform for creating both real social movements and more or less fleeting events, as manifestos or virtual campaigns. Nonetheless, in order to understand the role of virtual social networks in today’s world, we need to answer some prior questions. Are we facing a new communication model, whereby the product of “disinterested” interactivity creates an aura of confidence in disseminated information, often quite higher that that seen in the “old media”? Will that interactivity be a chance to fight-off citizens’ growing detachment with regard to the “res publica”? Will we find in citizen-made journalism, transmitted through virtual social networks, the consecration of a true fourth power? On the other hand, can we call the distinct collective movements we have seen emerging true “social movements”?The present article aims to examine this and other issues that come to the fore in the intricate social world of cyberspace.

  3. Communication and control for networked complex systems

    CERN Document Server

    Peng, Chen; Han, Qing-Long

    2015-01-01

    This book reports on the latest advances in the study of Networked Control Systems (NCSs). It highlights novel research concepts on NCSs; the analysis and synthesis of NCSs with special attention to their networked character; self- and event-triggered communication schemes for conserving limited network resources; and communication and control co-design for improving the efficiency of NCSs. The book will be of interest to university researchers, control and network engineers, and graduate students in the control engineering, communication and network sciences interested in learning the core principles, methods, algorithms and applications of NCSs.

  4. Modeling GSM Based Network Communication in Vehicular Network

    Directory of Open Access Journals (Sweden)

    M. Milton Joe

    2014-02-01

    Full Text Available Obviously fair communication establishment in every technology increases the efficiency. As we know well, vehicles are used in day to day life of every human being to move from one location to another location. If network communication is formed between vehicles, mobile phones and home based telephones, it will increase the safety of the passengers by communicating with one another. In this paper, we propose GSM based network communication in vehicles, which will develop reliable network communication between vehicles, mobile phones and home based telephones. The added advantage GSM based network communication among vehicles will lead to safety of travel by tracking the vehicle's location, since GSM based network communication is established in vehicles.

  5. The physics of communicability in complex networks

    Science.gov (United States)

    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.

  6. Distributed wireless quantum communication networks

    International Nuclear Information System (INIS)

    The distributed wireless quantum communication network (DWQCN) has a distributed network topology and transmits information by quantum states. In this paper, we present the concept of the DWQCN and propose a system scheme to transfer quantum states in the DWQCN. The system scheme for transmitting information between any two nodes in the DWQCN includes a routing protocol and a scheme for transferring quantum states. The routing protocol is on-demand and the routing metric is selected based on the number of entangled particle pairs. After setting up a route, quantum teleportation and entanglement swapping are used for transferring quantum states. Entanglement swapping is achieved along with the process of routing set up and the acknowledgment packet transmission. The measurement results of each entanglement swapping are piggybacked with route reply packets or acknowledgment packets. After entanglement swapping, a direct quantum link between source and destination is set up and quantum states are transferred by quantum teleportation. Adopting this scheme, the measurement results of entanglement swapping do not need to be transmitted specially, which decreases the wireless transmission cost and transmission delay. (general)

  7. Real-Time Communication Networks Onboard Ships

    DEFF Research Database (Denmark)

    Nielsen, Jens Frederik Dalsgaard; Nielsen, Kirsten Mølgaard; Jørgensen, N.

    1995-01-01

    This paper describes the ATOMOS communication network project carried out within the EU project ATOMOS, to be used for ISC purposes.......This paper describes the ATOMOS communication network project carried out within the EU project ATOMOS, to be used for ISC purposes....

  8. Effective Protocols for Mobile Communications and Networking

    Energy Technology Data Exchange (ETDEWEB)

    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.

  9. Communication and Networking in Smart Grids

    CERN Document Server

    Xiao, Yang

    2012-01-01

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

  10. Communication Performance Over A Gigabit Ethernet Network

    OpenAIRE

    Mr.Nitish Meena

    2014-01-01

    A present computing imposes heavy demands on the optical communication network. Gigabit Ethernet technology can provide the required bandwidth to meet these demands. However, it has also involve the communication Impediment to progress from network media to TCP(Transfer control protocol) processing. In this paper, present an overview of Gigabit per second Ethernet technology and study the end-to-end Gigabit Ethernet communication bandwidth and retrieval time. Performance graph...

  11. Communication on the structure of biological networks

    Indian Academy of Sciences (India)

    Deyasi Krishanu; Upadhyay Shashankaditya; Banerjee Anirban

    2016-03-01

    Networks are widely used to represent interaction pattern among the components in complex systems. Structures of real networks from different domains may vary quite significantly. As there is an interplay between network architecture and dynamics, structure plays an important role in communication and spreading of information in a network. Here we investigate the underlying undirected topology of different biological networks which support faster spreading of information and are better in communication. We analyse the good expansion property by using the spectral gap and communicability between nodes. Different epidemic models are also used to study the transmission of information in terms of spreading of disease through individuals (nodes)in those networks. Moreover, we explore the structural conformation and properties which may be responsible for better communication. Among all biological networks studied here, the undirected structure of neuronal networks not only possesses the small-world property but the same is also expressed remarkably to a higher degree compared to any randomly generated network which possesses the same degree sequence. A relatively high percentage of nodes, in neuronal networks, form a higher core in their structure. Our study shows that the underlying undirected topology in neuronal networks, in a significant way, is qualitatively different from the same in other biologicalnetworks and that they may have evolved in such a way that they inherit a (undirected) structure which is excellent and robust in communication.

  12. Corporate Communication in the Network Economy

    DEFF Research Database (Denmark)

    Foss, Nicolai Juul; Kristensen, Tore; Wilke, Ricky

    This paper draws on ideas in economics and game theory to develop a new theory of marketing and corporate communication in the emerging network economy. We argue that in a network economy, firms and consumers will confront `coordination problems.' With the emerging network economy all this become...... a simple game theoretic model to explain this, and discuss marketing applications and possible strategies.Key wordsCoordination problems, common knowledge, corporate communication...

  13. Modeling data throughput on communication networks

    Energy Technology Data Exchange (ETDEWEB)

    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.

  14. Flexible coprocessor architectures for ambient intelligent applications in the mobile communication and automotive domain

    Science.gov (United States)

    Gehrke, Winfried; Jachalsky, Joern; Wahle, Martin; Kruijtzer, Wido; Alba, Carlos; Sethuraman, Ramanathan

    2003-04-01

    Ambient Intelligent is expected to become one of the driving key factors of the semiconductors industry in this decade. One of the most promising areas in this respect is the advent of embedded smart imaging applications in a variety of consumer applications, like mobile communication devices and the automotive domain. The efficient VLSI implementation of these applications requires architectural concepts that enable the extraction of objects and associated information out of video sequences in real-time. The main architectural challenge is to find an appropriate trade-off between architectural flexibility and scalability in order to cope with moderate variations of the applied smart imaging algorithms on one hand and cost efficiency of the implementation on the other hand. This paper describes the algorithmic and architectural requirements for the implementation of smart imaging applications in the mentioned fields. The target system, based on an embedded RISC processor, embedded memory, and cores for accelerating essential functions, like morphological operations, connected component labeling, motion extraction etc., is presented. The functional system partitioning applied is based on HW acceleration of core functions that enable the extraction of low-level information out of the images of a video sequence. This information is provided to the embedded RISC processor for further abstraction of the image content information and interpretation of the image content by SW means. One of the focal points of this paper is the derivation of efficient architectural concepts for smart imaging coprocessors, acting as a system toolbox for accelerating the required smart imaging core functions.

  15. Applications of Coding in Network Communications

    Science.gov (United States)

    Chang, Christopher SungWook

    2012-01-01

    This thesis uses the tool of network coding to investigate fast peer-to-peer file distribution, anonymous communication, robust network construction under uncertainty, and prioritized transmission. In a peer-to-peer file distribution system, we use a linear optimization approach to show that the network coding framework significantly simplifies…

  16. Design Considerations for Multi-Channel Picture Communication Networks

    OpenAIRE

    Scheibe, Paul O.

    1983-01-01

    Design of networks intended for communication of digitally-encoded pictures involves considerations different from those used in the design of text or voice communication networks. This paper provides an overview of the elements useful in the design of picture communication networks by relation and contrast with other communication networks. Particular emphasis is given to picture communication systems useful in medical applications.

  17. Correlations, hierarchies and networks of the world’s automotive companies

    Science.gov (United States)

    Kocakaplan, Yusuf; Doğan, Şerafettin; Deviren, Bayram; Keskin, Mustafa

    2013-06-01

    We investigate, within the scope of econophysics, the correlations, hierarchies and networks of the world’s automotive companies over the 2003-2010 period by using the concept of a minimal spanning tree (MST) and hierarchical tree (HT). We derive a hierarchical organization and construct the MSTs and HTs for the 2003-2010 period and illustrate how the MSTs and their associated HTs developed over time. These periods are divided into two subperiods, such as 2003-2006 and 2007-2010, in order to test various time-windows and understand the temporal evolution of the correlation structure over time. We perform the bootstrap techniques to investigate a value of the statistical reliability to the links of the MSTs. We also use average linkage cluster analysis (ALCA) to observe the cluster structure more clearly in HTs. From the structural topologies of these trees, we identify different clusters of companies according to their geographical proximity and economic ties. Our results show that some companies are more important within the network, due to a tighter connection with other companies. We also find that these important companies play a predominant role in the world’s automotive industry.

  18. Communication cliques in mobile phone calling networks

    CERN Document Server

    Li, Ming-Xia; Jiang, Zhi-Qiang; Zhou, Wei-Xing

    2015-01-01

    People in modern societies form different social networks through numerous means of communication. These communication networks reflect different aspects of human's societal structure. The billing records of calls among mobile phone users enable us to construct a directed calling network (DCN) and its Bonferroni network (SVDCN) in which the preferential communications are statistically validated. Here we perform a comparative investigation of the cliques of the original DCN and its SVDCN constructed from the calling records of more than nine million individuals in Shanghai over a period of 110 days. We find that the statistical properties of the cliques of the two calling networks are qualitatively similar and the clique members in the DCN and the SVDCN exhibit idiosyncratic behaviors quantitatively. Members in large cliques are found to be spatially close to each other. Based on the clique degree profile of each mobile phone user, the most active users in the two calling networks can be classified in to seve...

  19. Efficient Networks Communication Routing Using Swarm Intelligence

    OpenAIRE

    Koushal Kumar

    2012-01-01

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

  20. The handbook of optical communication networks

    CERN Document Server

    Ilyas, Mohammad

    2003-01-01

    The Handbook of Optical Communication Networks presents comprehensive, up-to-date technical information on integrated, state-of-the-art optical networks. Beginning with an in-depth intoduction to the field, top international authorities explore every major aspect of optical networks, from basic concepts to research grade material. Their discussions cover all of the essential topics, including protocols, resource management, routing and wavelength assignment in WDM networks, connection management, survivability, enabling technologies, and future trends.

  1. The Physics of Communicability in Complex Networks

    CERN Document Server

    Estrada, Ernesto; Benzi, Michele

    2011-01-01

    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 grap...

  2. Future networks and technologies supporting innovative communications

    DEFF Research Database (Denmark)

    Prasad, Ramjee

    2012-01-01

    -communications (WISDOM) that combines the aspects of personal- and cognitive radio- networks to let seamlessly bridge the virtual and physical worlds offering a constant level of all-senses, context-based, rich communication experience over fixed and wireless networks for the end users while realizing a new generation......Within a fully interconnected world, the distinct relationship between end users, consumers and providers rapidly changes towards a scenario of collaboration and competition of multiple parties within one system. ‘Convergence’, ‘ubiquitous’ and ‘smart’ are key words describing future networks...... and applications. This paper focuses on the technological aspects of ubiquitous networking and communication technologies, including challenges related to green communications, and security, privacy and trust. The paper proposes a novel concept for a Wireless Innovative System for Dynamically Operating Mega...

  3. Location of terminals in a communications network

    DEFF Research Database (Denmark)

    2015-01-01

    A method (400, 500) of identifying nodes in a communications network is disclosed, the nodes being for use in locating wireless terminals within the network based upon reports from the wireless terminals of transmissions received from the nodes. The method (400, 500) comprises prioritising...... reference node. Also disclosed is a method (100, 200) for locating a plurality of wireless terminals in a communications network, the network comprising a plurality of network nodes at known locations, wherein the nodes emit wireless transmissions in an unsynchronised manner, such that a time difference...... exists between the emission time of corresponding transmissions from different nodes. The method comprises receiving reports from a plurality of wireless terminals of transmissions received from the network nodes (110, 210), selecting a subset of network nodes (120, 220) and identifying a plurality of...

  4. Switch for serial or parallel communication networks

    Science.gov (United States)

    Crosette, D.B.

    1994-07-19

    A communication switch apparatus and a method for use in a geographically extensive serial, parallel or hybrid communication network linking a multi-processor or parallel processing system has a very low software processing overhead in order to accommodate random burst of high density data. Associated with each processor is a communication switch. A data source and a data destination, a sensor suite or robot for example, may also be associated with a switch. The configuration of the switches in the network are coordinated through a master processor node and depends on the operational phase of the multi-processor network: data acquisition, data processing, and data exchange. The master processor node passes information on the state to be assumed by each switch to the processor node associated with the switch. The processor node then operates a series of multi-state switches internal to each communication switch. The communication switch does not parse and interpret communication protocol and message routing information. During a data acquisition phase, the communication switch couples sensors producing data to the processor node associated with the switch, to a downlink destination on the communications network, or to both. It also may couple an uplink data source to its processor node. During the data exchange phase, the switch couples its processor node or an uplink data source to a downlink destination (which may include a processor node or a robot), or couples an uplink source to its processor node and its processor node to a downlink destination. 9 figs.

  5. Performance measurement of the after-sales service network: Evidence from the automotive industry

    Directory of Open Access Journals (Sweden)

    Shahnoush Shahrouzi Fard

    2015-10-01

    Full Text Available This paper presents an empirical investigation to determine important factors influencing on customer satisfaction in after-sales service network of automotive industry. The study designs two questionnaires, one for measuring the quality of after-sales services and the other for measuring customers’ satisfaction. The study selects a sample of 265 randomly selected customers out of 850 people who received the services from an automotive firm in Iran. Cronbach alpha has calculated as 0.82, which is well above the minimum desirable level. Using Spearman correlation the study has detected a positive and meaningful relationship between services and customer satisfaction (r=0.48, Sig. =0.01, a positive relationship between being responsiveness and customer satisfaction (r=0.51, Sig. =0.01 and finally a positive relationship between speed of operation customer satisfaction (r=0.45, Sig. = 0.01. Moreover, there was a positive and meaningful relationship between cost of services and customer satisfaction (r=0.68, Sig. = 0.01 and a positive relationship between quality of services of after-sales services and customer satisfaction (r = 0.61, Sig. =0.01.

  6. Evolutionary dynamics of complex communications networks

    CERN Document Server

    Karyotis, Vasileios; Papavassiliou, Symeon

    2013-01-01

    Until recently, most network design techniques employed a bottom-up approach with lower protocol layer mechanisms affecting the development of higher ones. This approach, however, has not yielded fascinating results in the case of wireless distributed networks. Addressing the emerging aspects of modern network analysis and design, Evolutionary Dynamics of Complex Communications Networks introduces and develops a top-bottom approach where elements of the higher layer can be exploited in modifying the lowest physical topology-closing the network design loop in an evolutionary fashion similar to

  7. Multicriteria Steiner Tree Problem for Communication Network

    CERN Document Server

    Levin, Mark Sh

    2011-01-01

    This paper addresses combinatorial optimization scheme for solving the multicriteria Steiner tree problem for communication network topology design (e.g., wireless mesh network). The solving scheme is based on several models: multicriteria ranking, clustering, minimum spanning tree, and minimum Steiner tree problem. An illustrative numerical example corresponds to designing a covering long-distance Wi-Fi network (static Ad-Hoc network). The set of criteria (i.e., objective functions) involves the following: total cost, total edge length, overall throughput (capacity), and estimate of QoS. Obtained computing results show the suggested solving scheme provides good network topologies which can be compared with minimum spanning trees.

  8. laboratories for Data Communications and Computer Networks

    OpenAIRE

    Goyal, Rohit; Lai, Steve; Jain, Raj; Durresi, Arian

    1998-01-01

    In this paper we describe a hands-on laboratory oriented instructional package that we have developed for data communications and networking. The package consists of a software tool, together with instructional material for a laboratory based networking curriculum. The software is based on a simulation environment that enables the student to experiment with various networking protocols, on an easy to use graphical user interface (GUI). Data message flows, packet losses, control/routing messag...

  9. Challenges of Integrating NASAs Space Communication Networks

    Science.gov (United States)

    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

  10. Challenges of Integrating NASA's Space Communications Networks

    Science.gov (United States)

    Reinert, Jessica; 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

  11. Network design tool for EHF satellite communications networks

    Science.gov (United States)

    Norvell, S.; Brown, G. J.

    1983-06-01

    This document describes the design concept of the network design tool. The network design tool (NDT) is a collection of analytical techniques, algorithms and simulation methods that may be used to characterize the performance of a computer communication network. Much work has been done over the past several years in network performance analysis and many techniques have been developed or proposed. Each of these methods applies to a particular aspect of the network design and is based on a particular modeling point of view. We define the computer communication network and then describe the different ways the network may be modeled. Each network model is related to the particular design problem being addressed. The various analytical approaches are briefly described and their relationship to the network models discussed. Chapter 2 is a survey of the major approaches to specific network design problems while chapters 3 and 4 discuss two fairly well defined areas of network analysis: topological design/optimization and protocol validation. Chapter 5 is a survey of network design tools presently available locally or on the advanced research projects agency network (ARPANET). Finally, chapter 6 presents an outline of the NDT specification.

  12. Modification and Validation of an Automotive Data Processing Unit, Compessed Video System, and Communications Equipment

    Energy Technology Data Exchange (ETDEWEB)

    Carter, R.J.

    1997-04-01

    The primary purpose of the "modification and validation of an automotive data processing unit (DPU), compressed video system, and communications equipment" cooperative research and development agreement (CRADA) was to modify and validate both hardware and software, developed by Scientific Atlanta, Incorporated (S-A) for defense applications (e.g., rotary-wing airplanes), for the commercial sector surface transportation domain (i.e., automobiles and trucks). S-A also furnished a state-of-the-art compressed video digital storage and retrieval system (CVDSRS), and off-the-shelf data storage and transmission equipment to support the data acquisition system for crash avoidance research (DASCAR) project conducted by Oak Ridge National Laboratory (ORNL). In turn, S-A received access to hardware and technology related to DASCAR. DASCAR was subsequently removed completely and installation was repeated a number of times to gain an accurate idea of complete installation, operation, and removal of DASCAR. Upon satisfactory completion of the DASCAR construction and preliminary shakedown, ORNL provided NHTSA with an operational demonstration of DASCAR at their East Liberty, OH test facility. The demonstration included an on-the-road demonstration of the entire data acquisition system using NHTSA'S test track. In addition, the demonstration also consisted of a briefing, containing the following: ORNL generated a plan for validating the prototype data acquisition system with regard to: removal of DASCAR from an existing vehicle, and installation and calibration in other vehicles; reliability of the sensors and systems; data collection and transmission process (data integrity); impact on the drivability of the vehicle and obtrusiveness of the system to the driver; data analysis procedures; conspicuousness of the vehicle to other drivers; and DASCAR installation and removal training and documentation. In order to identify any operational problems not captured by the systems

  13. Communication cliques in mobile phone calling networks

    Science.gov (United States)

    Li, Ming-Xia; Xie, Wen-Jie; Jiang, Zhi-Qiang; Zhou, Wei-Xing

    2015-11-01

    People in modern societies form different social networks through numerous means of communication. These communication networks reflect different aspects of human's societal structure. The billing records of calls among mobile phone users enable us to construct a directed calling network (DCN) and its Bonferroni network (SVDCN) in which the preferential communications are statistically validated. Here we perform a comparative investigation of the cliques of the original DCN and its SVDCN constructed from the calling records of more than nine million individuals in Shanghai over a period of 110 days. We find that the statistical properties of the cliques of the two calling networks are qualitatively similar and the clique members in the DCN and the SVDCN exhibit idiosyncratic behaviors quantitatively. Members in large cliques are found to be spatially close to each other. Based on the clique degree profile of each mobile phone user, the most active users in the two calling networks can be classified in to several groups. The users in different groups are found to have different calling behaviors. Our study unveils interesting communication behaviors among mobile phone users that are densely connected to each other.

  14. Modeling MAC layer for powerline communications networks

    Science.gov (United States)

    Hrasnica, Halid; Haidine, Abdelfatteh

    2001-02-01

    The usage of electrical power distribution networks for voice and data transmission, called Powerline Communications, becomes nowadays more and more attractive, particularly in the telecommunication access area. The most important reasons for that are the deregulation of the telecommunication market and a fact that the access networks are still property of former monopolistic companies. In this work, first we analyze a PLC network and system structure as well as a disturbance scenario in powerline networks. After that, we define a logical structure of the powerline MAC layer and propose the reservation MAC protocols for the usage in the PLC network which provides collision free data transmission. This makes possible better network utilization and realization of QoS guarantees which can make PLC networks competitive to other access technologies.

  15. Communication Buses and Protocols for Sensor Networks

    Directory of Open Access Journals (Sweden)

    Andrew Mason

    2002-07-01

    Full Text Available This paper overviews existing digital communication buses which are commonly used in sensor networks, discusses sensor network architectures, and introduces a new sensor bus for low power microsystem applications. The new intra-module multi-element microsystem (IM2 bus is nine-line interface with 8b serial data which implements several advanced features such as power management and plug-n-play while maintaining minimum hardware overhead at the sensor node. Finally, some issues in wireless sensor networking are discussed. The coverage of these issues provides a guideline for choosing the appropriate bus for different sensor network applications.

  16. The entire network topology display system of terminal communication access network

    OpenAIRE

    An Yi

    2016-01-01

    Now order terminal communication access network is network technology in Shanxi Province is diversiform, device type complex, lack of unified technical standard, the terminal communication access network management system of construction constitutes a great obstacle. Need to build a “unified communication interface and communication standard, unified communications network management” of the terminal communication access network cut in the integrated network management system, for the termina...

  17. Quantum Advantage in Communication Networks

    OpenAIRE

    De, Aditi Sen; Sen, Ujjwal

    2011-01-01

    Quantum channels are known to provide qualitatively better information transfer capacities over their classical counterparts. Examples include quantum cryptography, quantum dense coding, and quantum teleportation. This is a short review on paradigmatic quantum communication protocols in both bipartite as well as multipartite scenarios.

  18. Case studies of attacks on communication networks

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Sin Bok; Han, Eon Suk [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

    1996-06-15

    Recently, as the computer hardware and communications are developed, the data exchange through inter-networking has been highlighted and the data is being recognized as a great asset. Most of the organizations, businesses and enterprises are open to the external world-computer communication networks, attention must be focused on the securities of the information infrastructure. A government organization has been developing 'Circuits Analyzers', and 'Hacker-Tracking Program' and is struggling to track down sneakers. In this report, we analyze the contents of the cases where the communication network has been invaded, from the past up until now in Korea. This report also contains the result of a study on E-mail security, for the protection of KAERI Integrated Management Information System under which utilizes the CALS concepts and web services. (Author)

  19. Entangled Network and Quantum Communication

    CERN Document Server

    Metwally, Nasser

    2011-01-01

    A theoretical scheme is introduced to generate entangled network via Dzyaloshinskii- Moriya (DM)interaction. The dynamics of entanglement generated between different nodes by direct or indirect interaction is investigated. It is shown that, the direction of (DM) interaction and the location of the nodes have a sensational effect on the degree of entanglement. We quantify the minimum entanglement generated between all the nodes. The upper and lower bound of the entanglement of the generated network depends on the direction of DM interaction and the repetition of the behavior depends on the strength of DM. The generated entangled nodes are used as quantum channel to perform quantum teleportation, where we show that the fidelity of teleporting unknown information between the network members depends on the location of the members.

  20. Wireless Networks for Body-Centric Communications

    OpenAIRE

    Martelli, Flavia

    2013-01-01

    Progress in miniaturization of electronic components and design of wireless systems paved the way towards ubiquitous and pervasive communications, enabling anywhere and anytime connectivity. Wireless devices present on, inside, around the human body are becoming commonly used, leading to the class of body-centric communications. The presence of the body with all its peculiar characteristics has to be properly taken into account in the development and design of wireless networks in this con...

  1. Intelligent Communication Module for Wireless Biosensor Networks

    OpenAIRE

    Naik, R.; Singh, J.; Le, H. P.

    2010-01-01

    This chapter presented a new paradigm of biosensors which have processing capability with an intelligent and adaptive wireless communication module. The adaptive communication module efficiently reconfigures its hardware components according to the changes in operating environment in order to reduce system power consumption and optimally utilise resources. The chapter presented several significant applications of wireless biosensor networks which hold enormous potential to benefit the communi...

  2. Green networking and communications ICT for sustainability

    CERN Document Server

    Khan, Shafiullah

    2013-01-01

    Although the information and communication technology (ICT) industry accounted for only 2 percent of global greenhouse gas emissions in 2007, the explosive increase in data traffic brought about by a rapidly growing user base of more than a billion wireless subscribers is expected to nearly double that number by 2020. It is clear that now is the time to rethink how we design and build our networks.Green Networking and Communications: ICT for Sustainability brings together leading academic and industrial researchers from around the world to discuss emerging developments in energy-efficient netw

  3. An underwater optical wireless communication network

    Science.gov (United States)

    Arnon, Shlomi

    2009-08-01

    The growing need for underwater observation and sub-sea monitoring systems has stimulated considerable interest in advancing the enabling technologies of underwater wireless communication and underwater sensor networks. This communication technology is expected to play an important role in investigating climate change, in monitoring biological, bio-geochemical, evolutionary and ecological changes in the sea, ocean and lake environments and in helping to control and maintain oil production facilities and harbors using unmanned underwater vehicles (UUVs), submarines, ships, buoys, and divers. However, the present technology of underwater acoustic communication cannot provide the high data rate required to investigate and monitor these environments and facilities. Optical wireless communication has been proposed as the best alternative to meet this challenge. We present models of three kinds of optical wireless communication links a) a line-of-sight link, b) a modulating retro-reflector link and c) a reflective link, all of which can provide the required data rate. We analyze the link performance based on these models. From the analysis, it is clear that as the water absorption increases, the communication performance decreases dramatically for the three link types. However, by using the scattered lighted it was possible to mitigate this decrease in some cases. We conclude from the analysis that a high data rate underwater optical wireless network is a feasible solution for emerging applications such as UUV to UUV links and networks of sensors, and extended ranges in these applications could be achieved by applying a multi-hop concept.

  4. Critical size of ego communication networks

    CERN Document Server

    Wang, Qing; Zhou, Tao; Hu, Zheng; Tian, Hui

    2016-01-01

    With the help of information and communication technologies, studies on the overall social networks have been extensively reported recently. However, investigations on the directed Ego Communication Networks (ECNs) remain insufficient, where an ECN stands for a sub network composed of a centralized individual and his/her direct contacts. In this paper, the directed ECNs are built on the Call Detail Records (CDRs), which cover more than 7 million people of a provincial capital city in China for half a year. Results show that there is a critical size for ECN at about 150, above which the average emotional closeness between ego and alters drops, the balanced relationship between ego and network collapses, and the proportion of strong ties decreases. This paper not only demonstrate the significance of ECN size in affecting its properties, but also shows accordance with the "Dunbar's Number". These results can be viewed as a cross-culture supportive evidence to the well-known Social Brain Hypothesis (SBH).

  5. Global Production Sharing in the Australian Automotive Trade

    OpenAIRE

    Kishor Sharma

    2012-01-01

    This paper contributes to the literature on global production sharing by investigating the experience of the Australian automotive industry, which has experienced significant structural change following trade liberalisation. Our analysis indicates that the globalisation of the world economy, together with developments in transport and communication, has significantly increased the importance of the global production network in the Australian automotive industry, leading to a substantial rise ...

  6. A Communications Network for Cislunar Operations

    Science.gov (United States)

    Burleigh, Scott

    2012-01-01

    Reliable and efficient communications will be critical to the success of commercial flight operations in cislunar space. The Internet is not well-suited to meeting this requirement. But the Delay-Tolerant Networking (DTN) architecture is. The DTN protocols are well-documented and implementations are mature. We think DTN will be ready to support low-cost, low-risk cislunar networking by the time the vehicles are in place.

  7. Efficient Networks Communication Routing Using Swarm Intelligence

    Directory of Open Access Journals (Sweden)

    Koushal Kumar

    2012-11-01

    Full Text Available As demonstrated by natural biological swarm’s collective intelligence has an abundance of desirable properties for problem-solving like in network routing. The focus of this paper is in the applications of swarm based intelligence in information routing for communication networks. As we know networks are growing and adopting new platforms as new technologies comes. Also according to new demands and requirements networks topologies and its complexity is increasing with time. Thus it is becoming very difficult to maintain the quality of services and reliability of the networks using current Networks routing algorithms. Thus Swarm intelligence (SI is the collective behavior of decentralized self-organized systems, natural or artificial. The concept is employed in work on artificial intelligence. A new class of algorithms, inspired by swarm intelligence is currently being developed that can potentially solve numerous problems of modern communications networks. These algorithms rely on the interaction of a multitude of simultaneously interacting agents. In this paper we give disadvantages of previously used network routing algorithms and how we can apply swarm intelligence to overcome these problems.

  8. Green Communications and Networks : Proceedings of the International Conference on Green Communications and Networks

    CERN Document Server

    Ma, Maode

    2012-01-01

    Green Communications and Networks presents 95 papers chosen for publication from among 190 reviewed papers accepted for presentation to the International Conference on Green Communications and Networks (GCN 2011), held in Chongqing, China, July 15-17, 2011. GCN 2011 provided a venue for leading academic and industrial researchers to exchange their views, ideas and research results on innovative technologies and sustainable solutions leading to greener communications and networks. In addition to paper presentations, the conference featured keynote speakers and a panel discussion. Reflecting the broad scope of the conference, the contents are organized in these topical categories: Communication Systems Data Management and Database System Digital Image Processing Education and Informatics Enabling Technologies Forensics, Recognition Technologies and Applications Fuzzy System and Control Graphics and Visualizing Green Computing Internet Growth Modelling and Virtualized Networks Network Components and Application ...

  9. Infotainment and road safety service support in vehicular networking: From a communication perspective

    Science.gov (United States)

    Cheng, Ho Ting; Shan, Hangguan; Zhuang, Weihua

    2011-08-01

    Vehicular ad hoc networking is an emerging technology for future on-the-road communications. Due to the virtue of vehicle-to-vehicle and vehicle-to-infrastructure communications, vehicular ad hoc networks (VANETs) are expected to enable a plethora of communication-based automotive applications including diverse in-vehicle infotainment applications and road safety services. Even though vehicles are organized mostly in an ad hoc manner in the network topology, directly applying the existing communication approaches designed for traditional mobile ad hoc networks to large-scale VANETs with fast-moving vehicles can be ineffective and inefficient. To achieve success in a vehicular environment, VANET-specific communication solutions are imperative. In this paper, we provide a comprehensive overview of various radio channel access protocols and resource management approaches, and discuss their suitability for infotainment and safety service support in VANETs. Further, we present recent research activities and related projects on vehicular communications. Potential challenges and open research issues are also discussed.

  10. Hybrid Mobile Communication Networks for Planetary Exploration

    Science.gov (United States)

    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.

  11. Entangled network and quantum communication

    Energy Technology Data Exchange (ETDEWEB)

    Metwally, Nasser, E-mail: Nmetwally@gmail.com [Math. Dept., Faculty of Science, South Valley University, Aswan (Egypt); Math. Dept., College of Science, University of Bahrain, P.O. Box 32038 (Bahrain)

    2011-11-21

    A theoretical scheme is introduced to generate entangled network via Dzyaloshinskii–Moriya (DM) interaction. The dynamics of entanglement between different nodes, which is generated by direct or indirect interaction, is investigated. It is shown that, the direction of (DM) interaction and the locations of the nodes have a sensational effect on the degree of entanglement. The minimum entanglement generated between all the nodes is quantified. The upper and lower bounds of the entanglement depend on the direction of DM interaction, and the repetition of the behavior depends on the strength of DM. The generated entangled nodes are used as quantum channel to perform quantum teleportation, where it is shown that the fidelity of teleporting unknown information between the network members depends on the locations of the members.

  12. Social networks: communication and change

    OpenAIRE

    Gustavo Cardoso; Cláudia Lamy

    2011-01-01

    Virtual social networks have brought about the possibility for open and plural debate, where all those with the necessary literacy skills and means are able to participate in the creation and dissemination of information. By pressing political agents and determining the “agenda” of a lot of the media, users demonstrate that we stand at an ideal platform for creating both real social movements and more or less fleeting events, as manifestos or virtual campaigns. Nonetheless, in order to under...

  13. Detecting and Locating Failures in Communication Networks

    Institute of Scientific and Technical Information of China (English)

    史维更; R.JamesDuckworth

    1990-01-01

    The connectivity of a strongly connected network may be destroyed after link damage.Since many networks are connected by directed links,the reachability may be restore by altering the direction of one or more of the links and thus reconfiguring the network.The location of the failed link ust first be determined.In this paper,we examine new methods to determine the location of failed links and nodes in networks.A routing test approach is proposed and the conditions under which communication networks may be tested are discussed Finally,an adaptive algorithm and a heuristic algorithm that can locate a single failed link or a single failed node are presented.

  14. Communication services for advanced network applications.

    Energy Technology Data Exchange (ETDEWEB)

    Bresnahan, J.; Foster, I.; Insley, J.; Toonen, B.; Tuecke, S.

    1999-06-10

    Advanced network applications such as remote instrument control, collaborative environments, and remote I/O are distinguished by traditional applications such as videoconferencing by their need to create multiple, heterogeneous flows with different characteristics. For example, a single application may require remote I/O for raw datasets, shared controls for a collaborative analysis system, streaming video for image rendering data, and audio for collaboration. Furthermore, each flow can have different requirements in terms of reliability, network quality of service, security, etc. They argue that new approaches to communication services, protocols, and network architecture are required both to provide high-level abstractions for common flow types and to support user-level management of flow creation and quality. They describe experiences with the development of such applications and communication services.

  15. INTERNET FOR VANET NETWORK COMMUNICATIONS -FLEETNET

    Directory of Open Access Journals (Sweden)

    Bahidja Boukenadil

    2014-12-01

    Full Text Available Now in the world, the exchange of information between vehicles in the roads without any fixed infrastructure is enabled thanks to the novel technology of the Vehicular ad hoc networks called (VANETs. The accidents and congestions warning, Internet access e.g. via gateways along the road are the main applications of these networks related to the safety and comfort applications. A high requirement on the routing protocols is introduced in these complexed VANETs networks In order to implement a reference intelligent transportation system and contribute to the standardization of vehicle to vehicle communication or vehicle to infrastructure, in Europe, several projects are held and different partners are joined from the industry, governmental agencies and academia. This paper explains the main progress and purposes of the standardization process and research initiatives of FleetNet project. These solutions will present in the future a common worldwide VANET platform integrating several services of inter-vehicles communications

  16. Energy, Entropy and Exergy in Communication Networks

    Directory of Open Access Journals (Sweden)

    Slavisa Aleksic

    2013-10-01

    Full Text Available The information and communication technology (ICT sector is continuously growing, mainly due to the fast penetration of ICT into many areas of business and society. Growth is particularly high in the area of technologies and applications for communication networks, which can be used, among others, to optimize systems and processes. The ubiquitous application of ICT opens new perspectives and emphasizes the importance of understanding the complex interactions between ICT and other sectors. Complex and interacting heterogeneous systems can only properly be addressed by a holistic framework. Thermodynamic theory, and, in particular, the second law of thermodynamics, is a universally applicable tool to analyze flows of energy. Communication systems and their processes can be seen, similar to many other natural processes and systems, as dissipative transformations that level differences in energy density between participating subsystems and their surroundings. This paper shows how to apply thermodynamics to analyze energy flows through communication networks. Application of the second law of thermodynamics in the context of the Carnot heat engine is emphasized. The use of exergy-based lifecycle analysis to assess the sustainability of ICT systems is shown on an example of a radio access network.

  17. Cell Multiprocessor Communication Network: Built for Speed

    International Nuclear Information System (INIS)

    The existence of major obstacles to the traditional path to processor performance improvement has led chip manufacturers to consider multi-core designs. These architectural solutions promise a variety of power/performance and area/performance benefits. But additional care must be taken to ensure that these benefits are not lost due to inadequate design of the on-chip communication network. This paper presents the design challenges of the on-chip network of the Cell Broadband Engine (Cell BE) processor, and describes in detail its architectural design and the network, communication and synchronization protocols. In the experimental evaluation, performed on an early prototype, we analyze the communication characteristics of the Cell BE processor, using a series of microbenchmarks involving various DMA traffic patterns and synchronization protocols. We find that the on-chip communication subsystem is well matched to the to computational capacity of the processor. A Synergistic Processing Element (SPE) can issue an internal direct memory access (DMA) operation in less than 4 nanoseconds, and a DMA of a single cache line can be executed in less the than 100 nanoseconds. SPEs can achieve the optimal bandwidth of 25.6 GB/second in point to point communication with surprisingly small messages ?only a few KB, using batches of non-blocking DMAs. The aggregate network behavior under heavy load is also remarkably efficient, reaching almost 200 GB/second with collective patterns and optimal contention resolution under hot-spot traffic. Additionally, we demonstrate the consistency of these hardware results with identical experiments carried out using the Mambo simulator software for Cell BE

  18. Communication through resonance in spiking neuronal networks.

    Science.gov (United States)

    Hahn, Gerald; Bujan, Alejandro F; Frégnac, Yves; Aertsen, Ad; Kumar, Arvind

    2014-08-01

    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.

  19. Communication shapes sensory response in multicellular networks.

    Science.gov (United States)

    Potter, Garrett D; Byrd, Tommy A; Mugler, Andrew; Sun, Bo

    2016-09-13

    Collective sensing by interacting cells is observed in a variety of biological systems, and yet, a quantitative understanding of how sensory information is collectively encoded is lacking. Here, we investigate the ATP-induced calcium dynamics of monolayers of fibroblast cells that communicate via gap junctions. Combining experiments and stochastic modeling, we find that increasing the ATP stimulus increases the propensity for calcium oscillations, despite large cell-to-cell variability. The model further predicts that the oscillation propensity increases with not only the stimulus, but also the cell density due to increased communication. Experiments confirm this prediction, showing that cell density modulates the collective sensory response. We further implicate cell-cell communication by coculturing the fibroblasts with cancer cells, which we show act as "defects" in the communication network, thereby reducing the oscillation propensity. These results suggest that multicellular networks sit at a point in parameter space where cell-cell communication has a significant effect on the sensory response, allowing cells to simultaneously respond to a sensory input and the presence of neighbors.

  20. Life Cycle Assessment of Process Eco-Innovations in an SME Automotive Supply Network

    Directory of Open Access Journals (Sweden)

    Alberto Simboli

    2015-10-01

    Full Text Available The aim of the study presented in this article is to assess, from an environmental standpoint, a set of eco-innovations applied to the production process of an automotive component. The eco-innovations were developed by a supply network of small- and medium-sized enterprises (SMEs in the framework of a project named “Hi-reach”. The component considered is a motorcycle rear wheel spindle. The conventional version is obtained by machining a single forged steel part. The Hi-reach version is indeed manufactured by joining a shaft to a flange; in addition, conventional surface treatments are replaced by a plasma-enhanced chemical vapour deposition (PECVD treatment and other machining steps are improved. This process was conceived with the aim of maintaining (or enhancing the technical performance of the spindle and reducing production costs. A Life Cycle Assessment (LCA was carried out to compare the two scenarios described. Those eco-innovations resulted in significant improvements of the environmental performance of the analysed component, ranging, on average, between 50% and 70% for the impact indicators considered. Our results also highlight the role of SMEs in promoting process eco-innovations and the increasing relevance of LCA as a tool to support decision making in manufacturing.

  1. Anonymous communication networks protecting privacy on the web

    CERN Document Server

    Peng, Kun

    2014-01-01

    In today's interactive network environment, where various types of organizations are eager to monitor and track Internet use, anonymity is one of the most powerful resources available to counterbalance the threat of unknown spectators and to ensure Internet privacy.Addressing the demand for authoritative information on anonymous Internet usage, Anonymous Communication Networks: Protecting Privacy on the Web examines anonymous communication networks as a solution to Internet privacy concerns. It explains how anonymous communication networks make it possible for participants to communicate with

  2. Resource Management in Broadband Communication Networks

    DEFF Research Database (Denmark)

    Hansen, Mads Stenhuus

    2003-01-01

    This thesis - Resource Management in Broadband Communication Networks - deals with different ways of optimizing the available resources of data- or telecommunication networks. Especially topics like optimal routing, load balancing and fast recovery of routes in case of link failures are covered......, that reflects the situation in a competitive telecommunication market, with several service providers sharing the same physical network. The investigation of the simulated ants, on the other hand, gives a many promising results, suggesting that they can successfully be used to solve some problems...... a virtually unprecedented robustness. A network with failing components typically return to a fully operational state within seconds or even faster. Hopefully these results of the investigation of simulated ants - along with other results from the literature - can contribute to make the big manufacturers...

  3. Communication via an entangled coherent quantum network

    Energy Technology Data Exchange (ETDEWEB)

    El Allati, A; Hassouni, Y [Faculte des Sciences, Departement de Physique, Laboratoire de Physique Theorique URAC 13, Universite Mohammed V Agdal Rabat, Avenue Ibn Battouta, B.P. 1014, Rabat (Morocco); Metwally, N, E-mail: Nmetwally@gmail.com [Mathematics Department, College of Science, University of Bahrain, PO Box 32038 (Bahrain)

    2011-06-01

    A quantum network (QN) is constructed via maximum entangled coherent states. The possibility of using this network to achieve quantum communication between multi-participants is investigated. We showed that the probability of the successful teleportation of an unknown state depends on the size of the used network. As the number of participants increases, the success probability does not depend on the intensity of the field. Implementing a quantum teleportation protocol via a noisy QN is discussed. The unknown state can be teleported perfectly with small values of the field intensity and larger values of the noise strength. The success probability of this suggested protocol increases abruptly for larger values of the noise strength and gradually for small values. For small-size QNs, the fidelity of the teleported state decreases smoothly, whereas it decreases abruptly for larger-sized networks.

  4. Towards risk-aware communications networking

    International Nuclear Information System (INIS)

    We promote introduction of risk-awareness in the design and operation of communications networks and services. This means explicit and systematic consideration of uncertainties related to improper behavior of the web of interdependent networks and the resulting consequences for individuals, companies and a society as a whole. Central activities are the recognition of events challenging dependability together with the assessment of their probabilities and impacts. While recognizing the complex technical, business and societal issues, we employ an overall risk framing approach containing risk assessment, response and monitoring. Our paradigm gathers topics that are currently dispersed in various fields of network activities. We review the current state of risk-related activities in networks, identify deficiencies and challenges, and suggest techniques, procedures, and metrics towards higher risk-awareness.

  5. Local-area communication networks - An overview

    International Nuclear Information System (INIS)

    Local-area communication networks represent a new field of activity. In this paper we first describe three scenarios for the use of these networks, and then discuss various technical approaches. Particular emphasis is put on bus and ring systems with various media access control mechanisms. Specifically, we compare the delay-throughput characteristic of two access methods, carrier-sense multiple access with collision detection and token passing, and discuss some significant differences of bus and ring systems concerning wiring, media, transmission, and reliability. (orig.)

  6. Position estimation of transceivers in communication networks

    Science.gov (United States)

    Kent, Claudia A.; Dowla, Farid

    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.

  7. Weighted reciprocity in human communication networks

    OpenAIRE

    Wang, Cheng; Strathman, Anthony; Lizardo, Omar; Hachen, David; Toroczkai, Zoltan; Chawla, Nitesh V.

    2011-01-01

    In this paper we define a metric for reciprocity---the degree of balance in a social relationship---appropriate for weighted social networks in order to investigate the distribution of this dyadic feature in a large-scale system built from trace-logs of over a billion cell-phone communication events across millions of actors. We find that dyadic relations in this network are characterized by much larger degrees of imbalance than we would expect if persons kept only those relationships that ex...

  8. Satellite communications network design and analysis

    CERN Document Server

    Jo, Kenneth Y

    2011-01-01

    This authoritative book provides a thorough understanding of the fundamental concepts of satellite communications (SATCOM) network design and performance assessments. You find discussions on a wide class of SATCOM networks using satellites as core components, as well as coverage key applications in the field. This in-depth resource presents a broad range of critical topics, from geosynchronous Earth orbiting (GEO) satellites and direct broadcast satellite systems, to low Earth orbiting (LEO) satellites, radio standards and protocols.This invaluable reference explains the many specific uses of

  9. Capacity analysis of vehicular communication networks

    CERN Document Server

    Lu, Ning

    2013-01-01

    This SpringerBrief focuses on the network capacity analysis of VANETs, a key topic as fundamental guidance on design and deployment of VANETs is very limited. Moreover, unique characteristics of VANETs impose distinguished challenges on such an investigation. This SpringerBrief first introduces capacity scaling laws for wireless networks and briefly reviews the prior arts in deriving the capacity of VANETs. It then studies the unicast capacity considering the socialized mobility model of VANETs. With vehicles communicating based on a two-hop relaying scheme, the unicast capacity bound is deriv

  10. Linear programming and algorithms for communication networks a practical guide to network design, control, and management

    CERN Document Server

    Oki, Eiji

    2012-01-01

    Explaining how to apply to mathematical programming to network design and control, Linear Programming and Algorithms for Communication Networks: A Practical Guide to Network Design, Control, and Management fills the gap between mathematical programming theory and its implementation in communication networks. From the basics all the way through to more advanced concepts, its comprehensive coverage provides readers with a solid foundation in mathematical programming for communication networks. Addressing optimization problems for communication networks, including the shortest path problem, max f

  11. Secure Communication in Stochastic Wireless Networks

    CERN Document Server

    Pinto, Pedro C; Win, Moe Z

    2010-01-01

    Information-theoretic security -- widely accepted as the strictest notion of security -- relies on channel coding techniques that exploit the inherent randomness of the propagation channels to significantly strengthen the security of digital communications systems. Motivated by recent developments in the field, this paper aims at a characterization of the fundamental secrecy limits of wireless networks. Based on a general model in which legitimate nodes and potential eavesdroppers are randomly scattered in space, the intrinsically secure communications graph (iS-graph) is defined from the point of view of information-theoretic security. Conclusive results are provided for the local connectivity of the Poisson iS-graph, in terms of node degrees and isolation probabilities. It is shown how the secure connectivity of the network varies with the wireless propagation effects, the secrecy rate threshold of each link, and the noise powers of legitimate nodes and eavesdroppers. Sectorized transmission and eavesdroppe...

  12. An FPGA-based torus communication network

    International Nuclear Information System (INIS)

    We describe the design and FPGA implementation of a 3D torus network (TNW) to provide nearest-neighbor communications between commodity multi-core processors. The aim of this project is to build up tightly interconnected and scalable parallel systems for scientific computing. The design includes the VHDL code to implement on latest FPGA devices a network processor, which can be accessed by the CPU through a PCIe interface and which controls the external PHYs of the physical links. Moreover, a Linux driver and a library implementing custom communication APIs are provided. The TNW has been successfully integrated in two recent parallel machine projects, QPACE and AuroraScience. We describe some details of the porting of the TNW for the AuroraScience system and report performance results. (orig.)

  13. An FPGA-based torus communication network

    Energy Technology Data Exchange (ETDEWEB)

    Pivanti, Marcello; Schifano, Sebastiano Fabio [INFN, Ferrara (Italy); Ferrara Univ. (Italy); Simma, Hubert [DESY, Zeuthen (Germany). John von Neumann-Institut fuer Computing NIC

    2011-02-15

    We describe the design and FPGA implementation of a 3D torus network (TNW) to provide nearest-neighbor communications between commodity multi-core processors. The aim of this project is to build up tightly interconnected and scalable parallel systems for scientific computing. The design includes the VHDL code to implement on latest FPGA devices a network processor, which can be accessed by the CPU through a PCIe interface and which controls the external PHYs of the physical links. Moreover, a Linux driver and a library implementing custom communication APIs are provided. The TNW has been successfully integrated in two recent parallel machine projects, QPACE and AuroraScience. We describe some details of the porting of the TNW for the AuroraScience system and report performance results. (orig.)

  14. NOVANET: communications network for a control system

    International Nuclear Information System (INIS)

    NOVANET is a control system oriented fiber optic local area network that was designed to meet the unique and often conflicting requirements of the Nova laser control system which will begin operation in 1984. The computers and data acquisition devices that form the distributed control system for a large laser fusion research facility need reliable, high speed communications. Both control/status messages and experimental data must be handled. A subset of NOVANET is currently operating on the two beam Novette laser system

  15. Discovery Monday - Behind the plug: communication networks

    CERN Multimedia

    2004-01-01

    Ever wondered what happens to your email when you click "send"? And when you make a phone call, how does your voice travel down the wire? Find out more about communication networks and their applications. Do not miss the next Discovery Monday in Microcosm on 1st March (see Bulletin 9/2004)! Monday 1st March from 7.30pm to 9.00pm, in Microcosm. Entrance Free.

  16. Communication Performance Over A Gigabit Ethernet Network

    Directory of Open Access Journals (Sweden)

    Mr.Nitish Meena

    2014-09-01

    Full Text Available A present computing imposes heavy demands on the optical communication network. Gigabit Ethernet technology can provide the required bandwidth to meet these demands. However, it has also involve the communication Impediment to progress from network media to TCP(Transfer control protocol processing. In this paper, present an overview of Gigabit per second Ethernet technology and study the end-to-end Gigabit Ethernet communication bandwidth and retrieval time. Performance graphs are collected using NetPipe in this clearly show the performance characteristics of TCP/IP over Gigabit Ethernet. These indicate the impact of a number of factors such as processor speeds, network adaptors, versions of the Linux Kernel or opnet softwar and device drivers, and TCP/IP(Internet protocol tuning on the performance of Gigabit Ethernet between two Pentium II/350 PCs. Among the important conclusions are the marked superiority of the 2.1.121 and later development kernels and 2.2.x production kernels of Linux or opnet softwar used and that the ability to increase the MTU(maximum transmission unit Further than the Ethernet standard of 1500 could significantly enhance the throughput reachable.

  17. Critical size of ego communication networks

    Science.gov (United States)

    Wang, Qing; Gao, Jian; Zhou, Tao; Hu, Zheng; Tian, Hui

    2016-06-01

    With the help of information and communication technologies, studies on the overall social networks have been extensively reported recently. However, investigations on the directed Ego Communication Networks (ECNs) remain insufficient, where an ECN stands for a sub network composed of a centralized individual and his/her direct contacts. In this paper, the directed ECNs are built on the Call Detail Records (CDRs), which cover more than 7 million people of a provincial capital city in China for half a year. Results show that there is a critical size for ECN at about 150, above which the average emotional closeness between ego and alters drops, the balanced relationship between ego and network collapses, and the proportion of strong ties decreases. This paper not only demonstrate the significance of ECN size in affecting its properties, but also shows accordance with the “Dunbar's Number”. These results can be viewed as a cross-culture supportive evidence to the well-known Social Brain Hypothesis (SBH).

  18. Community detection based on network communicability

    Science.gov (United States)

    Estrada, Ernesto

    2011-03-01

    We propose a new method for detecting communities based on the concept of communicability between nodes in a complex network. This method, designated as N-ComBa K-means, uses a normalized version of the adjacency matrix to build the communicability matrix and then applies K-means clustering to find the communities in a graph. We analyze how this method performs for some pathological cases found in the analysis of the detection limit of communities and propose some possible solutions on the basis of the analysis of the ratio of local to global densities in graphs. We use four different quality criteria for detecting the best clustering and compare the new approach with the Girvan-Newman algorithm for the analysis of two "classical" networks: karate club and bottlenose dolphins. Finally, we analyze the more challenging case of homogeneous networks with community structure, for which the Girvan-Newman completely fails in detecting any clustering. The N-ComBa K-means approach performs very well in these situations and we applied it to detect the community structure in an international trade network of miscellaneous manufactures of metal having these characteristics. Some final remarks about the general philosophy of community detection are also discussed.

  19. Creativity, social networking and changing business communication

    Directory of Open Access Journals (Sweden)

    Saif Hossain

    2013-04-01

    Full Text Available This paper reviews literature on creativity, innovations, and creative organizations. An analytical approach has been undertaken using various articles to identify the need of innovation and creativity in today's world and how the innovation of social networking is changing business activities. Creativity and innovation are crucial factors for the endurance and progression of organizations in today's world. From the macroeconomic perspective, innovation is also related with economic growth, development of living standards and a country's international competiveness. The need for innovation is assisted by Information technology in a range of ways and in this contemporary era it is hard to separate innovation and technology due to its incredible offerings in all kinds of industries and sectors. One such innovation was 'social networking and social media.' In this epoch of social media, businesses are obliged to be extra transparent and more personal. This does not eradicate the need of customary advertising, but social networks allow an innovative form of communication which altered the approach of doing businesses. Businesses must concentrate on developing real and direct connections with customers. Companies which lag behind to change to this new trend and culture will be in damaging situation, as competitors will progressively try to reap the benefits out of it. All in all businesses need to adapt with the growing importance and impact of social networking as a means of communication.

  20. Control and Communication Network in Hybrid Fuel Cell Vehicles

    Institute of Scientific and Technical Information of China (English)

    朱元; 吴昊; 田光宇; 阳宪惠; 赵立安; 周伟波

    2004-01-01

    This paper describes the control and communication network in fuel cell vehicles, including both the protocol and the hardware.Based on the current protocol (ISO-11898 and SAE J1939), a new practical protocol is proposed and implemented for the control and communication network in fuel cell vehicles.To improve the reliability of data communication and to unify the network management, a new network system based on dual-port RAM is also implemented.

  1. Communication Timing Control with Interference Detection for Wireless Sensor Networks

    OpenAIRE

    Kokuke Sekiyama; Yuki Kubo

    2006-01-01

    This paper deals with a novel communication timing control for wireless networks and radio interference problem. Communication timing control is based on the mutual synchronization of coupled phase oscillatory dynamics with a stochastic adaptation, according to the history of collision frequency in communication nodes. Through local and fully distributed interactions in the communication network, the coupled phase dynamics self-organizes collision-free communication. In wireless communicatio...

  2. Architecting Communication Network of Networks for Space System of Systems

    Science.gov (United States)

    Bhasin, Kul B.; Hayden, Jeffrey L.

    2008-01-01

    The National Aeronautics and Space Administration (NASA) and the Department of Defense (DoD) are planning Space System of Systems (SoS) to address the new challenges of space exploration, defense, communications, navigation, Earth observation, and science. In addition, these complex systems must provide interoperability, enhanced reliability, common interfaces, dynamic operations, and autonomy in system management. Both NASA and the DoD have chosen to meet the new demands with high data rate communication systems and space Internet technologies that bring Internet Protocols (IP), routers, servers, software, and interfaces to space networks to enable as much autonomous operation of those networks as possible. These technologies reduce the cost of operations and, with higher bandwidths, support the expected voice, video, and data needed to coordinate activities at each stage of an exploration mission. In this paper, we discuss, in a generic fashion, how the architectural approaches and processes are being developed and used for defining a hypothetical communication and navigation networks infrastructure to support lunar exploration. Examples are given of the products generated by the architecture development process.

  3. Marketing communications model for innovation networks

    Directory of Open Access Journals (Sweden)

    Tiago João Freitas Correia

    2015-10-01

    Full Text Available Innovation is an increasingly relevant concept for the success of any organization, but it also represents a set of internal and external considerations, barriers and challenges to overcome. Along the concept of innovation, new paradigms emerge such as open innovation and co-creation that are simultaneously innovation modifiers and intensifiers in organizations, promoting organizational openness and stakeholder integration within the value creation process. Innovation networks composed by a multiplicity of agents in co-creative work perform as innovation mechanisms to face the increasingly complexity of products, services and markets. Technology, especially the Internet, is an enabler of all process among organizations supported by co-creative platforms for innovation. The definition of marketing communication strategies that promote motivation and involvement of all stakeholders in synergic creation and external promotion is the central aspect of this research. The implementation of the projects is performed by participative workshops with stakeholders from Madan Parque through IDEAS(REVOLUTION methodology and the operational model LinkUp parameterized for the project. The project is divided into the first part, the theoretical framework, and the second part where a model is developed for the marketing communication strategies that appeal to the Madan Parque case study. Keywords: Marketing Communication; Open Innovation, Technology; Innovation Networks; Incubator; Co-Creation.

  4. Survey of Tolerant Network in Mobile Communication

    Directory of Open Access Journals (Sweden)

    M.Chithik Raja

    2012-01-01

    Full Text Available Tolerant networks are a class of emerging networks that experience frequent and long-duration partitions. These networks have a variety of applications in situations such as crisis environments and deep-space communication. In this paper, we study the problem of multicasting in TNs. Multicast supports the distribution of data to a group of users, a service needed for many potential TN applications. While multicasting in the Internet and mobile ad hoc networks has been studied extensively, due to the unique characteristic of frequent partitioning in TNs, multicasting in TNs is a considerably different and challenging problem. It not only requires new definitions of multicast semantics but also brings new issues to the design of routing algorithms. In this pa- per, we propose new semantic models for TN multicast and develop several multicast routing algorithms with different routing strategies. We present a framework to evaluate these algorithms in TNs. To the best of our knowledge, this is the first study of multicasting in TNs. Our objectives are to understand how routing performance is affected by the availability of knowledge about network topology and group membership and to guide the design of TN routing protocols. Using ns simulations, we find that efficient multicast routing for TNs can be constructed using only partial knowledge. In addition, accurate topology information is generally more important in routing than up-to-date membership information. We also find that routing algorithms that forward data along multiple paths achieve better delivery ratios, especially when available knowledge is limited.

  5. Modeling of PEM Fuel Cell Stack System using Feed-forward and Recurrent Neural Networks for Automotive Applications

    Directory of Open Access Journals (Sweden)

    Mr. M. Karthik

    2014-05-01

    Full Text Available Artificial Neural Network (ANN has become a significant modeling tool for predicting the performance of complex systems that provide appropriate mapping between input-output variables without acquiring any empirical relationship due to the intrinsic properties. This paper is focussed towards the modeling of Proton Exchange Membrane (PEM Fuel Cell system using Artificial Neural Networks especially for automotive applications. Three different neural networks such as Static Feed Forward Network (SFFN, Cascaded Feed Forward Network (CFFN & Fully Connected Dynamic Recurrent Network (FCRN are discussed in this paper for modeling the PEM Fuel Cell System. The numerical analysis is carried out between the three Neural Network architectures for predicting the output performance of the PEM Fuel Cell. The performance of the proposed Networks is evaluated using various error criteria such as Mean Square Error, Mean Absolute Percentage Error, Mean Absolute Error, Coefficient of correlation and Iteration Values. The optimum network with high performance indices (low prediction error values and iteration values can be used as an ancillary model in developing the PEM Fuel Cell powered vehicle system. The development of the fuel cell driven vehicle model also incorporates the modeling of DC-DC Power Converter and Vehicle Dynamics. Finally the Performance of the Electric vehicle model is analyzed for two different drive cycle such as M-NEDC & M-UDDS.

  6. Opportunistic spectrum utilization in vehicular communication networks

    CERN Document Server

    Cheng, Nan

    2016-01-01

    This brief examines current research on improving Vehicular Networks (VANETs), examining spectrum scarcity due to the dramatic growth of mobile data traffic and the limited bandwidth of dedicated vehicular communication bands and the use of opportunistic spectrum bands to mitigate congestion. It reviews existing literature on the use of opportunistic spectrum bands for VANETs, including licensed and unlicensed spectrum bands and a variety of related technologies, such as cognitive radio, WiFi and device-to-device communications. Focused on analyzing spectrum characteristics, designing efficient spectrum exploitation schemes, and evaluating the date delivery performance when utilizing different opportunistic spectrum bands, the results presented in this brief provide valuable insights on improving the design and deployment of future VANETs.

  7. Reliable Communication Models in Interdependent Critical Infrastructure Networks

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Sangkeun (Matt) [ORNL; Chinthavali, Supriya [ORNL; Shankar, Mallikarjun [ORNL

    2016-01-01

    Modern critical infrastructure networks are becoming increasingly interdependent where the failures in one network may cascade to other dependent networks, causing severe widespread national-scale failures. A number of previous efforts have been made to analyze the resiliency and robustness of interdependent networks based on different models. However, communication network, which plays an important role in today's infrastructures to detect and handle failures, has attracted little attention in the interdependency studies, and no previous models have captured enough practical features in the critical infrastructure networks. In this paper, we study the interdependencies between communication network and other kinds of critical infrastructure networks with an aim to identify vulnerable components and design resilient communication networks. We propose several interdependency models that systematically capture various features and dynamics of failures spreading in critical infrastructure networks. We also discuss several research challenges in building reliable communication solutions to handle failures in these models.

  8. Network Internet-communications as an instrument of marketing

    OpenAIRE

    Kaluzhsky, Mikhail; Karpov, Valery

    2015-01-01

    The article is about the features of application of network Internet-communications for advancement of the goods. Wide development of Internet technologies has transformed social communications into the independent tool of marketing. Authors classify and analyze possibilities of use of network Internet-communications in the marketing environment.

  9. Fixed-wing drones for communication networks

    OpenAIRE

    Varga, Maja

    2016-01-01

    In the last decade, drones became frequently used to provide eye-in-the-sky overview in the outdoor environment. Their main advantage compared to the other types of robots is that they can fly above obstacles and rough terrains and they can quickly cover large areas. These properties also open a new application; drones could provide a multi-hop, line of sight communication for groups of ground users. The aim of this thesis is to develop a drone team that will establish wireless ad-hoc network...

  10. Game theory for wireless communications and networking

    CERN Document Server

    Zhang, Yan

    2011-01-01

    Used to explain complicated economic behavior for decades, game theory is quickly becoming a tool of choice for those serious about optimizing next generation wireless systems. Illustrating how game theory can effectively address a wide range of issues that until now remained unresolved, Game Theory for Wireless Communications and Networking provides a systematic introduction to the application of this powerful and dynamic tool. This comprehensive technical guide explains game theory basics, architectures, protocols, security, models, open research issues, and cutting-edge advances and applica

  11. The Dynamics of Initiative in Communication Networks

    CERN Document Server

    Mollgaard, Anders

    2016-01-01

    Human social interaction is often intermittent. Two acquainted persons can have extended periods without social interaction punctuated by periods of repeated interaction. In this case, the repeated interaction can be characterized by a seed initiative by either of the persons and a number of follow-up interactions. The tendency to initiate social interaction plays an important role in the formation of social networks and is in general not symmetric between persons. In this paper, we study the dynamics of initiative by analysing and modeling a detailed call and text message network sampled from a group of 700 individuals. We show that in an average relationship between two individuals, one part is almost twice as likely to initiate communication compared to the other part. The asymmetry has social consequences and ultimately might lead to the discontinuation of a relationship. We explain the observed asymmetry by a positive feedback mechanism where individuals already taking initiative are more likely to take ...

  12. Communication security in open health care networks.

    Science.gov (United States)

    Blobel, B; Pharow, P; Engel, K; Spiegel, V; Krohn, R

    1999-01-01

    Fulfilling the shared care paradigm, health care networks providing open systems' interoperability in health care are needed. Such communicating and co-operating health information systems, dealing with sensitive personal medical information across organisational, regional, national or even international boundaries, require appropriate security solutions. Based on the generic security model, within the European MEDSEC project an open approach for secure EDI like HL7, EDIFACT, XDT or XML has been developed. The consideration includes both securing the message in an unsecure network and the transport of the unprotected information via secure channels (SSL, TLS etc.). Regarding EDI, an open and widely usable security solution has been specified and practically implemented for the examples of secure mailing and secure file transfer (FTP) via wrapping the sensitive information expressed by the corresponding protocols. The results are currently prepared for standardisation. PMID:10724890

  13. Stegobot: construction of an unobservable communication network leveraging social behavior

    CERN Document Server

    Nagaraja, Shishir; Piyawongwisal, Pratch; Singh, Vijit; Agarwal, Pragya; Borisov, Nikita

    2011-01-01

    We propose the construction of an unobservable communications network using social networks. The communication endpoints are vertices on a social network. Probabilistically unobservable communication channels are built by leveraging image steganography and the social image sharing behavior of users. All communication takes place along the edges of a social network overlay connecting friends. We show that such a network can provide decent bandwidth even with a far from optimal routing mechanism such as restricted flooding. We show that such a network is indeed usable by constructing a botnet on top of it, called Stegobot. It is designed to spread via social malware attacks and steal information from its victims. Unlike conventional botnets, Stegobot traffic does not introduce new communication endpoints between bots. We analyzed a real-world dataset of image sharing between members of an online social network. Analysis of Stegobot's network throughput indicates that stealthy as it is, it is also functionally p...

  14. GAS MAIN SENSOR AND COMMUNICATIONS NETWORK SYSTEM

    Energy Technology Data Exchange (ETDEWEB)

    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.

  15. Trends in Area of Safety Communications within Industrial Networks

    OpenAIRE

    Maria Franekova; Ales Janota; Karol Rastocny

    2005-01-01

    The paper deals with the problems of safety communication in industrial networks for purpose of assurance of functional safety. It is intents on analysis of treats on industry networks and there is described recommended safety protections and their location into layer communication protocol applicable in fieldbus network, which they are used within safety critical processes control.

  16. Network Analysis as a Communication Audit Instrument: Uncovering Communicative Strengths and Weaknesses Within Organizations

    NARCIS (Netherlands)

    Zwijze-Koning, Karen H.; Jong, de M.D.T.

    2015-01-01

    Network analysis is one of the instruments in the communication audit toolbox to diagnose communication problems within organizations. To explore its contribution to a communication audit, the authors conducted a network analysis within three secondary schools, comparing its results with those of tw

  17. Reliability evaluation of communication network switching scheme for safety systems

    International Nuclear Information System (INIS)

    To develop the communication network architecture of a safety system of nuclear power plant, the five essence in the design requirements of a communication network for safety-critical systems are determined such as status based architecture, deterministic scheme, separation and isolation, high reliability, verification and validation. In this paper, the data communication network switching scheme for safety systems is proposed based on the circuit switched network with time division multiplexing bus technology considered adequate to the essence of the design requirements and the design elements. The proposed communication network switching scheme was applied to the network design of the SMART protection system, and the reliability was evaluated with the data of components failure rates to determine the applicability of the proposed switching scheme. The proposed switching scheme will be applied as basic communication network architecture of safety system

  18. A Communicative Image of Social Network Audience: Psycholinguistic Perpective

    OpenAIRE

    Kompantseva, Larysa

    2014-01-01

    Abstract. In the paper, anthropocentrism is proved to be the basis of psycholinguistic research of Internet social communities; net-centricity is viewed as a cognitive basis of network communications; as exemplified by social networks VKontakte, YouTube, Odnoklassniki, and Facebook communicative portraits of audiences in psycholinguistic dimension are proposed. It was determined, that social network communities are becoming a platform for interpersonal communications, producing Web-waves...

  19. Gas Main Sensor and Communications Network System

    Energy Technology Data Exchange (ETDEWEB)

    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.

  20. Improving use case definition using enterprise communication networks

    OpenAIRE

    Luzuriaga, Juan Manuel

    2005-01-01

    Although researchers noted the importance of effective communication among stakeholders, it continues to be a challenge for requirements engineering. Communication can be considered as a management tool since communication allows organisation’s personnel to produce a cohesive enterprise view. In this paper, we briefly introduce our proposal on using enterprise communication networks to facilitate domain understanding. Then, we illustrate how to take advantage of these networks to improve use ...

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

    CERN Document Server

    Antoniou, Josephina

    2012-01-01

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

  2. Discovery Monday - Behind the plug: communication networks

    CERN Multimedia

    2004-01-01

    Ever wondered what happens to your email when you click "send"? And when you make a phone call, how does your voice travel down the wire? Find out more about communication networks and their applications at the next Discovery Monday in Microcosm on 1 March. At CERN, networks are used for a multitude of reasons. Mobile phones, for example, are used in the laboratory's underground areas. Optical fibre cabling ensures that CERN's computers are connected to the rest of the world. But how do optical fibres work and what does the future have in store? CERN's experiments also need networks. Particle detectors are made of many layers, each relays complex information to a computer analysis centre which reconstitutes the passage of the particles resulting from collisions. Many billions of bytes are transmitted every second from a multitude of sources, to many computers.  No single computer can handle such a huge flow of information. The next Discovery Monday is your chance to find out how this works.  Participate i...

  3. 76 FR 23812 - Reliability and Continuity of Communications Networks, Including Broadband Technologies; Effects...

    Science.gov (United States)

    2011-04-28

    ... COMMISSION Reliability and Continuity of Communications Networks, Including Broadband Technologies; Effects on Broadband Communications Networks of Damage or Failure of Network Equipment or Severe Overload; Independent Panel Reviewing the Impact of Hurricane Katrina on Communications Networks AGENCY:...

  4. Exploring the morphospace of communication efficiency in complex networks.

    Directory of Open Access Journals (Sweden)

    Joaquín Goñi

    Full Text Available Graph theoretical analysis has played a key role in characterizing global features of the topology of complex networks, describing diverse systems such as protein interactions, food webs, social relations and brain connectivity. How system elements communicate with each other depends not only on the structure of the network, but also on the nature of the system's dynamics which are constrained by the amount of knowledge and resources available for communication processes. Complementing widely used measures that capture efficiency under the assumption that communication preferentially follows shortest paths across the network ("routing", we define analytic measures directed at characterizing network communication when signals flow in a random walk process ("diffusion". The two dimensions of routing and diffusion efficiency define a morphospace for complex networks, with different network topologies characterized by different combinations of efficiency measures and thus occupying different regions of this space. We explore the relation of network topologies and efficiency measures by examining canonical network models, by evolving networks using a multi-objective optimization strategy, and by investigating real-world network data sets. Within the efficiency morphospace, specific aspects of network topology that differentially favor efficient communication for routing and diffusion processes are identified. Charting regions of the morphospace that are occupied by canonical, evolved or real networks allows inferences about the limits of communication efficiency imposed by connectivity and dynamics, as well as the underlying selection pressures that have shaped network topology.

  5. Exploring the morphospace of communication efficiency in complex networks.

    Science.gov (United States)

    Goñi, Joaquín; Avena-Koenigsberger, Andrea; Velez de Mendizabal, Nieves; van den Heuvel, Martijn P; Betzel, Richard F; Sporns, Olaf

    2013-01-01

    Graph theoretical analysis has played a key role in characterizing global features of the topology of complex networks, describing diverse systems such as protein interactions, food webs, social relations and brain connectivity. How system elements communicate with each other depends not only on the structure of the network, but also on the nature of the system's dynamics which are constrained by the amount of knowledge and resources available for communication processes. Complementing widely used measures that capture efficiency under the assumption that communication preferentially follows shortest paths across the network ("routing"), we define analytic measures directed at characterizing network communication when signals flow in a random walk process ("diffusion"). The two dimensions of routing and diffusion efficiency define a morphospace for complex networks, with different network topologies characterized by different combinations of efficiency measures and thus occupying different regions of this space. We explore the relation of network topologies and efficiency measures by examining canonical network models, by evolving networks using a multi-objective optimization strategy, and by investigating real-world network data sets. Within the efficiency morphospace, specific aspects of network topology that differentially favor efficient communication for routing and diffusion processes are identified. Charting regions of the morphospace that are occupied by canonical, evolved or real networks allows inferences about the limits of communication efficiency imposed by connectivity and dynamics, as well as the underlying selection pressures that have shaped network topology.

  6. Communication and cooperation in underwater acoustic networks

    Science.gov (United States)

    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

  7. Analysis of Spatial and Economical Effects in Communication Networks

    OpenAIRE

    Hanawal, Manjesh Kumar

    2013-01-01

    Ph.D. Thesis In this thesis we analyze the performance of communication networks using game theoretic approaches. The thesis is in two parts. The first part studies the performance of Ad hoc, cellular and transportation networks taking into consideration spatial effects. The second part studies economic issues in the communication networks related to the 'net neutrality' regulations. Here we study price competition and revenue sharing mechanisms between the network service providers. In th...

  8. Power distribution and performance analysis for wireless communication networks

    CERN Document Server

    Zhao, Dongmei

    2012-01-01

    This book provides an analysis of transmission power and network performance in different wireless communication networks. It presents the latest research and techniques for power and interference control and performance modeling in wireless communication networks with different network topologies, air interfaces, and transmission techniques. While studying the power distributions and resource management, the reader will also learn basic methodology and skills for problem formulations, can ascertain the complexity for designing radio resource management strategies in modern wireless communicat

  9. Time concurrency/phase-time synchronization in digital communications networks

    Science.gov (United States)

    Kihara, Masami; Imaoka, Atsushi

    1990-01-01

    Digital communications networks have the intrinsic capability of time synchronization which makes it possible for networks to supply time signals to some applications and services. A practical estimation method for the time concurrency on terrestrial networks is presented. By using this method, time concurrency capability of the Nippon Telegraph and Telephone Corporation (NTT) digital communications network is estimated to be better than 300 ns rms at an advanced level, and 20 ns rms at final level.

  10. A Guide to Computer Communications and Data Networks for Astronomers

    Science.gov (United States)

    Murtagh, F.

    1986-11-01

    Contents: The user view of networks. The standards organisations. General characteristics of wide area networks. The communications subnet and its protocols. End-to-end and user protocols. TOP and MAP implementations of OST. Some established networks. Connecting networks together. The future. Sources and further reading. Index and Acronyms.

  11. Extended master equation models for molecular communication networks

    CERN Document Server

    Chou, Chun Tung

    2012-01-01

    We consider molecular communication networks consisting of transmitters and receivers distributed in a fluidic medium. In such networks, a transmitter sends one or more signalling molecules, which are diffused over the medium, to the receiver to realise the communication. In order to be able to engineer synthetic molecular communication networks, mathematical models for these networks are required. This paper proposes a new stochastic model for molecular communication networks called reaction-diffusion master equation with exogenous input (RDMEX). The key idea behind RDMEX is to model the transmitters as time sequences specify the emission patterns of signalling molecules, while diffusion in the medium and chemical reactions at the receivers are modelled as Markov processes using master equation. An advantage of RDMEX is that it can readily be used to model molecular communication networks with multiple transmitters and receivers. For the case where the reaction kinetics at the receivers is linear, we show ho...

  12. Communicating oscillatory networks: frequency domain analysis

    Directory of Open Access Journals (Sweden)

    Ihekwaba Adaoha EC

    2011-12-01

    Full Text Available Abstract Background Constructing predictive dynamic models of interacting signalling networks remains one of the great challenges facing systems biology. While detailed dynamical data exists about individual pathways, the task of combining such data without further lengthy experimentation is highly nontrivial. The communicating links between pathways, implicitly assumed to be unimportant and thus excluded, are precisely what become important in the larger system and must be reinstated. To maintain the delicate phase relationships between signals, signalling networks demand accurate dynamical parameters, but parameters optimised in isolation and under varying conditions are unlikely to remain optimal when combined. The computational burden of estimating parameters increases exponentially with increasing system size, so it is crucial to find precise and efficient ways of measuring the behaviour of systems, in order to re-use existing work. Results Motivated by the above, we present a new frequency domain-based systematic analysis technique that attempts to address the challenge of network assembly by defining a rigorous means to quantify the behaviour of stochastic systems. As our focus we construct a novel coupled oscillatory model of p53, NF-kB and the mammalian cell cycle, based on recent experimentally verified mathematical models. Informed by online databases of protein networks and interactions, we distilled their key elements into simplified models containing the most significant parts. Having coupled these systems, we constructed stochastic models for use in our frequency domain analysis. We used our new technique to investigate the crosstalk between the components of our model and measure the efficacy of certain network-based heuristic measures. Conclusions We find that the interactions between the networks we study are highly complex and not intuitive: (i points of maximum perturbation do not necessarily correspond to points of maximum

  13. Message transfer in a communication network

    Indian Academy of Sciences (India)

    Satyam Mukherjee; Neelima Gupte

    2008-06-01

    We study message transfer in a 2-d communication network of regular nodes and randomly distributed hubs. We study both single message transfer and multiple message transfer on the lattice. The average travel time for single messages travelling between source and target pairs of fixed separations shows -exponential behaviour as a function of hub density with a characteristic power-law tail, indicating a rapid drop in the average travel time as a function of hub density. This power-law tail arises as a consequence of the log-normal distribution of travel times seen at high hub densities. When many messages travel on the lattice, a congestion-decongestion transition can be seen. The waiting times of messages in the congested phase show a Gaussian distribution, whereas the decongested phase shows a log-normal distribution. Thus the waiting time distributions carry the signature of congested or decongested behaviour.

  14. Test using communication satellite for security telecommunication network

    Energy Technology Data Exchange (ETDEWEB)

    Kimura, M.

    1988-01-01

    The authors confirmed by their experiment results that the satellite communication could be practically used for remote monitoring and control in gas distribution systems and data communication not only in emergency but also as the reinforced means of communication network. This report deals with the general description of the security communication network, our experiment of satellite operating system, the results and further plan for the practical application. Their company has started the test on the utilization of a communication satellite (CS-2 Japanese domestic communication satellite) since July, 1984, for the purpose of securing the telecommunication network in case of disaster and applying the satellite communications to data communication suitable for the information age, as for a gas utility industry.

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

    Science.gov (United States)

    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.

  16. Communicability Angle and the Spatial Efficiency of Networks

    CERN Document Server

    Estrada, Ernesto

    2014-01-01

    We introduce the concept of communicability angle between a pair of nodes in a graph. We provide strong analytical and empirical evidence that the average communicability angle for a given network accounts for its spatial efficiency on the basis of the communications among the nodes in a network. We determine characteristics of the spatial efficiency of more than a hundred real-world complex networks that represent complex systems arising in a diverse set of scenarios. In particular, we find that the communicability angle correlates very well with the experimentally measured the relative packing efficiency of proteins that are represented as residue networks. We finally show how we can modulate the spatial efficiency of a network by tuning the weights of the edges of the networks. This allows us to predict effects of external stresses on the spatial efficiency of a network as well as to design strategies to improve important parameters in real-world complex systems.

  17. Control and estimation methods over communication networks

    CERN Document Server

    Mahmoud, Magdi S

    2014-01-01

    This book provides a rigorous framework in which to study problems in the analysis, stability and design of networked control systems. Four dominant sources of difficulty are considered: packet dropouts, communication bandwidth constraints, parametric uncertainty, and time delays. Past methods and results are reviewed from a contemporary perspective, present trends are examined, and future possibilities proposed. Emphasis is placed on robust and reliable design methods. New control strategies for improving the efficiency of sensor data processing and reducing associated time delay are presented. The coverage provided features: ·        an overall assessment of recent and current fault-tolerant control algorithms; ·        treatment of several issues arising at the junction of control and communications; ·        key concepts followed by their proofs and efficient computational methods for their implementation; and ·        simulation examples (including TrueTime simulations) to...

  18. Communication networks beyond the capacity crunch.

    Science.gov (United States)

    Ellis, A D; Mac Suibhne, N; Saad, D; Payne, D N

    2016-03-01

    This issue of Philosophical Transactions of the Royal Society, Part A represents a summary of the recent discussion meeting 'Communication networks beyond the capacity crunch'. The purpose of the meeting was to establish the nature of the capacity crunch, estimate the time scales associated with it and to begin to find solutions to enable continued growth in a post-crunch era. The meeting confirmed that, in addition to a capacity shortage within a single optical fibre, many other 'crunches' are foreseen in the field of communications, both societal and technical. Technical crunches identified included the nonlinear Shannon limit, wireless spectrum, distribution of 5G signals (front haul and back haul), while societal influences included net neutrality, creative content generation and distribution and latency, and finally energy and cost. The meeting concluded with the observation that these many crunches are genuine and may influence our future use of technology, but encouragingly noted that research and business practice are already moving to alleviate many of the negative consequences.

  19. The Dynamics of Initiative in Communication Networks.

    Science.gov (United States)

    Mollgaard, Anders; Mathiesen, Joachim

    2016-01-01

    Human social interaction is often intermittent. Two acquainted persons can have extended periods without social interaction punctuated by periods of repeated interaction. In this case, the repeated interaction can be characterized by a seed initiative by either of the persons and a number of follow-up interactions. The tendency to initiate social interaction plays an important role in the formation of social networks and is in general not symmetric between persons. In this paper, we study the dynamics of initiative by analysing and modeling a detailed call and text message network sampled from a group of 700 individuals. We show that in an average relationship between two individuals, one part is almost twice as likely to initiate communication compared to the other part. The asymmetry has social consequences and ultimately might lead to the discontinuation of a relationship. We explain the observed asymmetry by a positive feedback mechanism where individuals already taking initiative are more likely to take initiative in the future. In general, people with many initiatives receive attention from a broader spectrum of friends than people with few initiatives. Lastly, we compare the likelihood of taking initiative with the basic personality traits of the five factor model.

  20. Preliminary OFDM based acoustic communication for underwater sensor networks synchronization

    OpenAIRE

    Pallarés Valls, Oriol; Sarriá Gandul, David; Viñolo Monzoncillo, Carlos; Río Fernandez, Joaquín del; Manuel Lázaro, Antonio

    2013-01-01

    This work presents a first approach to wireless underwater sensor networks UWSN time synchronization, using OFDM (Orthogonal Frequency Division Multiplexing) acoustic communication and time reference served by a synchronization protocol. This synchronization and type of modulation allows getting a low drift clock on each sensor, on a high efficiency underwater communication network. Peer Reviewed

  1. AUV Control and Communication using Underwater Acoustic Networks

    OpenAIRE

    Marques, Eduardo R.B.; Pinto, Marques; Kragelund, Sean; Dias, Paulo S.; Madureira, Luis; Sousa, Alexandre; Correia, Marcio; Ferreira, Hugo; Goncalves, Rui; Martins, Richardo; Horner, Douglas P.; Healey, Anthony J.; Goncalves, Gil M.; Sousa, Joao B.

    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.

  2. Recurrent-neural-network-based identification of a cascade hydraulic actuator for closed-loop automotive power transmission control

    International Nuclear Information System (INIS)

    By virtue of its ease of operation compared with its conventional manual counterpart, automatic transmissions are commonly used as automotive power transmission control system in today's passenger cars. In accordance with this trend, research efforts on closed-loop automatic transmission controls have been extensively carried out to improve ride quality and fuel economy. State-of-the-art power transmission control algorithms may have limitations in performance because they rely on the steady-state characteristics of the hydraulic actuator rather than fully exploit its dynamic characteristics. Since the ultimate viability of closed-loop power transmission control is dominated by precise pressure control at the level of hydraulic actuator, closed-loop control can potentially attain superior efficacy in case the hydraulic actuator can be easily incorporated into model-based observer/controller design. In this paper, we propose to use a recurrent neural network (RNN) to establish a nonlinear empirical model of a cascade hydraulic actuator in a passenger car automatic transmission, which has potential to be easily incorporated in designing observers and controllers. Experimental analysis is performed to grasp key system characteristics, based on which a nonlinear system identification procedure is carried out. Extensive experimental validation of the established model suggests that it has superb one-step-ahead prediction capability over appropriate frequency range, making it an attractive approach for model-based observer/controller design applications in automotive systems

  3. Recurrent-neural-network-based identification of a cascade hydraulic actuator for closed-loop automotive power transmission control

    Energy Technology Data Exchange (ETDEWEB)

    You, Seung Han [Hyundai Motor Company, Seoul (Korea, Republic of); Hahn, Jin Oh [University of Alberta, Edmonton (Canada)

    2012-05-15

    By virtue of its ease of operation compared with its conventional manual counterpart, automatic transmissions are commonly used as automotive power transmission control system in today's passenger cars. In accordance with this trend, research efforts on closed-loop automatic transmission controls have been extensively carried out to improve ride quality and fuel economy. State-of-the-art power transmission control algorithms may have limitations in performance because they rely on the steady-state characteristics of the hydraulic actuator rather than fully exploit its dynamic characteristics. Since the ultimate viability of closed-loop power transmission control is dominated by precise pressure control at the level of hydraulic actuator, closed-loop control can potentially attain superior efficacy in case the hydraulic actuator can be easily incorporated into model-based observer/controller design. In this paper, we propose to use a recurrent neural network (RNN) to establish a nonlinear empirical model of a cascade hydraulic actuator in a passenger car automatic transmission, which has potential to be easily incorporated in designing observers and controllers. Experimental analysis is performed to grasp key system characteristics, based on which a nonlinear system identification procedure is carried out. Extensive experimental validation of the established model suggests that it has superb one-step-ahead prediction capability over appropriate frequency range, making it an attractive approach for model-based observer/controller design applications in automotive systems.

  4. Information hiding in communication networks fundamentals, mechanisms, applications, and countermeasures

    CERN Document Server

    Mazurczyk, Wojciech; Zander, Sebastian; Houmansadr, Amir; Szczypiorski, Krzysztof

    2016-01-01

    Describes Information Hiding in communication networks, and highlights their important issues, challenges, trends, and applications. This book provides the fundamental concepts, terminology, and classifications of information hiding in communication networks along with its historical background. Information Hiding In Communication Networks: Fundamentals, Mechanisms, Applications, and Countermeasures begins with introducing data concealment methods and their evolution. Chapter two discusses the existing terminology and describes the model for hidden communication and related communication scenarios. Chapters three to five present the main classes of information hiding in communication networks accompanied by a discussion of their robustness and undetectability. The book concludes with a discussion of potential countermeasures against information hiding techniques, which includes different types of mechanisms for the detection, limitation and prevention of covert co munication channels.

  5. The Geospatial Characteristics of a Social Movement Communication Network

    CERN Document Server

    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...

  6. Novel Concepts for Device to Device Communication using Network Coding

    DEFF Research Database (Denmark)

    Pahlevani, Peyman; Hundebøll, Martin; Pedersen, Morten Videbæk;

    2014-01-01

    Device-to-device communication is currently a hot research topic within 3GPP. Even though D2D communication has been part of previous ad hoc, meshed and sensor networks proposals, the main contribution by 3GPP is that the direct communication among two devices is carried out over a dynamically as...

  7. Dynamic Pathloss Model for Future Mobile Communication Networks

    DEFF Research Database (Denmark)

    Kumar, Ambuj; Mihovska, Albena Dimitrova; Prasad, Ramjee

    2016-01-01

    — Future mobile communication networks (MCNs) are expected to be more intelligent and proactive based on new capabilities that increase agility and performance. However, for any successful mobile network service, the dexterity in network deployment is a key factor. The efficiency of the network p...... that incorporates the environmental dynamics factor in the propagation model for intelligent and proactively iterative networks...... that are essentially static. Therefore, once the signal level drops beyond the predicted values due to any variance in the environmental conditions, very crowded areas may not be catered well enough by the deployed network that had been designed with the static path loss model. This paper proposes an approach......— Future mobile communication networks (MCNs) are expected to be more intelligent and proactive based on new capabilities that increase agility and performance. However, for any successful mobile network service, the dexterity in network deployment is a key factor. The efficiency of the network...

  8. An Intelligent Wireless Sensor Networks System with Multiple Servers Communication

    OpenAIRE

    Jian-qiang Li; Sui-qiang He; Zhong Ming; Shubin Cai

    2015-01-01

    For shortcomings of current smart home system and power line carrier insufficient data transferring, an intelligent sensor networks system based on intelligent gateway is studied in this paper. Smart home system includes internal network, intelligent gateway, and external network. Multiple servers are designed in gateway, which start at the same time and receive various forms of data. Then data is processed for internal network format. External network includes several modes of communication ...

  9. Optimization of bandwidth of communication channels of corporate networks

    OpenAIRE

    G. I. Bondarenko; P. M. Korobenkov

    2014-01-01

    Introduction. This article contains overview of the organization of communication between applications on the corporate network. It is stated that the main digital channel (channel B - 64 kbit/s) and the primary digital channel (channel E1 the digital stream - 2048 kbit/s) are used as the main channels in corporate networks. Problem areas of the functioning of the corporate network are identified. There are the rent of communication channels, which is growing rapidly with increasing the quali...

  10. A fusion networking model for smart grid power distribution backbone communication network based on PTN

    Directory of Open Access Journals (Sweden)

    Wang Hao

    2016-01-01

    Full Text Available In current communication network for distribution in Chinese power grid systems, the fiber communication backbone network for distribution and TD-LTE power private wireless backhaul network of power grid are both bearing by the SDH optical transmission network, which also carries the communication network of transformer substation and main electric. As the data traffic of the distribution communication and TD-LTE power private wireless network grow rapidly in recent years, it will have a big impact with the SDH network’s bearing capacity which is mainly used for main electric communication in high security level. This paper presents a fusion networking model which use a multiple-layer PTN network as the unified bearing of the TD-LTE power private wireless backhaul network and fiber communication backbone network for distribution. Network dataflow analysis shows that this model can greatly reduce the capacity pressure of the traditional SDH network as well as ensure the reliability of the transmission of the communication network for distribution and TD-LTE power private wireless network.

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

    Science.gov (United States)

    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.

  12. Robust Networking Architecture and Secure Communication Scheme for Heterogeneous Wireless Sensor Networks

    Science.gov (United States)

    McNeal, McKenzie, III.

    2012-01-01

    Current networking architectures and communication protocols used for Wireless Sensor Networks (WSNs) have been designed to be energy efficient, low latency, and long network lifetime. One major issue that must be addressed is the security in data communication. Due to the limited capabilities of low cost and small sized sensor nodes, designing…

  13. Low power radio communication platform for wireless sensor network

    NARCIS (Netherlands)

    Dutta, R.; Bentum, M.J.; Zee, van der R.A.R.; Kokkeler, A.B.J.

    2009-01-01

    Wireless sensor networks are predicted to be the most versatile, popular and useful technology in the near future. A large number of applications are targeted which will hugely benefit from a network of tiny computers with few sensors, radio communication platform, intelligent networking and control

  14. Multi-path based secure communication in wireless mesh networks

    Institute of Scientific and Technical Information of China (English)

    Ding Xuyang; Fan Mingyu; Lu Xiaojun; Zhu Dayong; Wang Jiahao

    2007-01-01

    Communication security is a critical aspect of QoS provisioning in wireless mesh network (WMN).Because of the inherent characteristics of WMN, conventional security mechanisms cannot be applied. In order to guarantee the communication security, a novel communication security mechanism is proposed. The mechanism uses a communication encryption scheme to encrypt data packets and employs a risk avoidance scheme to avoid the malicious nodes during communications. Simulation results indicate that the mechanism is able to provide secure communication effectively and reduce the damage of attacks through multiple paths.

  15. Evaluation of Communication Overheads in Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Shiv Prasad Kori1 , Dr. R. K . Baghel2

    2013-04-01

    Full Text Available Wireless sensor network are collection of small sensing self powered nodes organized into a cooperative network which have certain processing capabilities and the nodes communicate wirelessly. Sensing, processing and communication are three key elements whose combination in one node gives rise to a vast number of applications of wireless sensor networks in areas such as environmental monitoring, warfare, education, agriculture to name a few. In the present work, the comparative evaluation of communication overhead due to sink mobility with speed variations, the effect of update time variation, the effect of number of nodes used in the wirelesssensor networks is carried out. It has been observed that communication overheads increasesignificantly when sink mobility is high. The communication overheads can be reduced by increasing update time

  16. 5th International Conference on Electronics, Communications and Networks

    CERN Document Server

    2016-01-01

    This book comprises peer-reviewed contributions presented at the 5th International Conference on Electronics, Communications and Networks (CECNet 2015), held in Shanghai, China, 12-15 December, 2015. It includes new multi-disciplinary topics spanning a unique depth and breadth of cutting-edge research areas in Electronic Engineering, Communications and Networks, and Computer Technology. More generally, it is of interest to academics, students and professionals involved in Consumer Electronics Technology, Communication Engineering and Technology, Wireless Communication Systems and Technology, and Computer Engineering and Technology.

  17. Advanced Communication and Networking Technologies for Mars Exploration

    Science.gov (United States)

    Bhasin, Kul; Hayden, Jeff; Agre, Jonathan R.; Clare, Loren P.; Yan, Tsun-Yee

    2001-01-01

    Next-generation Mars communications networks will provide communications and navigation services to a wide variety of Mars science vehicles including: spacecraft that are arriving at Mars, spacecraft that are entering and descending in the Mars atmosphere, scientific orbiter spacecraft, spacecraft that return Mars samples to Earth, landers, rovers, aerobots, airplanes, and sensing pods. In the current architecture plans, the communication services will be provided using capabilities deployed on the science vehicles as well as dedicated communication satellites that will together make up the Mars network. This network will evolve as additional vehicles arrive, depart or end their useful missions. Cost savings and increased reliability will result from the ability to share communication services between missions. This paper discusses the basic architecture that is needed to support the Mars Communications Network part of NASA's Space Science Enterprise (SSE) communications architecture. The network may use various networking technologies such as those employed in the terrestrial Internet, as well as special purpose deep-space protocols to move data and commands autonomously between vehicles, at disparate Mars vicinity sites (on the surface or in near-Mars space) and between Mars vehicles and earthbound users. The architecture of the spacecraft on-board local communications is being reconsidered in light of these new networking requirements. The trend towards increasingly autonomous operation of the spacecraft is aimed at reducing the dependence on resource scheduling provided by Earth-based operators and increasing system fault tolerance. However, these benefits will result in increased communication and software development requirements. As a result, the envisioned Mars communications infrastructure requires both hardware and protocol technology advancements. This paper will describe a number of the critical technology needs and some of the ongoing research

  18. Wireless Communication Networks' Planning in Underdeveloped Countries%Wireless Communication Networks' Planning in Underdeveloped Countries

    Institute of Scientific and Technical Information of China (English)

    XU Rui

    2012-01-01

    The planning of wireless communication networks in underdeveloped countries is studied for landline telephone, fixed broadband wireless access and PLMN systems via investigation and discussion of the LDC networks' characteristic, technology selection, deployment consideration, network configuring, civil work evaluation and investment estimation. An example is embedded all through providing a general

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

    Directory of Open Access Journals (Sweden)

    Mohamed A. Ahmed

    2016-03-01

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

  20. Design and analysis of the satellite laser communications network

    Science.gov (United States)

    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-δ) 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.

  1. 2014 International Conference on Wireless Communications, Networking and Applications

    CERN Document Server

    2016-01-01

    This book is based on a series of conferences on Wireless Communications, Networking and Applications that have been held on December 27-28, 2014 in Shenzhen, China. The meetings themselves were a response to technological developments in the areas of wireless communications, networking and applications and facilitate researchers, engineers and students to share the latest research results and the advanced research methods of the field. The broad variety of disciplines involved in this research and the differences in approaching the basic problems are probably typical of a developing field of interdisciplinary research. However, some main areas of research and development in the emerging areas of wireless communication technology can now be identified. The contributions to this book are mainly selected from the papers of the conference on wireless communications, networking and applications and reflect the main areas of interest: Section 1 - Emerging Topics in Wireless and Mobile Computing and Communications...

  2. Structure and tie strengths in mobile communication networks

    CERN Document Server

    Onnela, J P; Hyvönen, J; Kaski, K; Kertész, J; Lazer, D; Saramäki, J; Szabó, G

    2006-01-01

    Electronic databases, from phone to emails logs, currently provide detailed records of human communication patterns, offering novel avenues to map and explore the structure of social and communication networks. Here we examine the communication patterns of millions of mobile phone users, allowing us to simultaneously study the local and the global structure of a society-wide communication network. We observe a coupling between interaction strengths and the network's local structure, with the counterintuitive consequence that social networks are robust to the removal of the strong ties, but fall apart following a phase transition if the weak ties are removed. We show that this coupling significantly slows the diffusion process, resulting in dynamic trapping of information in communities, and find that when it comes to information diffusion, weak and strong ties are both simultaneously ineffective.

  3. Effective capacity analysis of smart grid communication networks.

    OpenAIRE

    You, Minglei; Mou, Xiaolin; Sun, Hongjian

    2015-01-01

    Smart grid represents a significant new technology of improving the efficiency, reliability and economics of the production, transmission and distribution of electricity that helps reduce carbon emissions. Communication networks become a key to achieving smart grid benefits due to their capability of delivering data and control signals. However, there does not exist a unified approach to quantify how well a communication network supports smart grid applications. In this paper, effective capac...

  4. Collaborative Algorithms for Communication in Wireless Sensor Networks

    OpenAIRE

    Nieberg, Tim; Dulman, Stefan; Havinga, Paul; Hoesel, van, CPM Stan; Wu, Jian; Basten, Twan; Geilen, Marc; Groot

    2003-01-01

    In this paper, we present the design of the communication in a wireless sensor network. The resource limitations of a wireless sensor network, especially in terms of energy, require an integrated, and collaborative approach for the different layers of communication. In particular, energy-efficient solutions for medium access control, clusterbased routing, and multipath creation and exploitation are discussed. The proposed MAC protocol is autonomous, decentralized and designed to minimize powe...

  5. Collaborative algorithms for communication in wireless sensor networks

    OpenAIRE

    Nieberg, Tim; Dulman, Stefan; Havinga, Paul; Hoesel, van, CPM Stan; Wu, Jian

    2003-01-01

    In this paper, we present the design of the communication in a wireless sensor network. The resource limitations of a wireless sensor network, especially in terms of energy, require an integrated, and collaborative approach for the different layers of communication. In particular, energy-efficient solutions for medium access control, clusterbased routing, and multipath creation and exploitation are discussed. The proposed MAC protocol is autonomous, decentralized and designed to minimize powe...

  6. Fast Structuring of Radio Networks for Multi-Message Communications

    OpenAIRE

    Ghaffari, Mohsen; Haeupler, Bernhard

    2014-01-01

    We introduce collision free layerings as a powerful way to structure radio networks. These layerings can replace hard-to-compute BFS-trees in many contexts while having an efficient randomized distributed construction. We demonstrate their versatility by using them to provide near optimal distributed algorithms for several multi-message communication primitives. Designing efficient communication primitives for radio networks has a rich history that began 25 years ago when Bar-Yehuda et al. in...

  7. Minimizing communication cost among distributed controllers in software defined networks

    Science.gov (United States)

    Arlimatti, Shivaleela; Elbreiki, Walid; Hassan, Suhaidi; Habbal, Adib; Elshaikh, Mohamed

    2016-08-01

    Software Defined Networking (SDN) is a new paradigm to increase the flexibility of today's network by promising for a programmable network. The fundamental idea behind this new architecture is to simplify network complexity by decoupling control plane and data plane of the network devices, and by making the control plane centralized. Recently controllers have distributed to solve the problem of single point of failure, and to increase scalability and flexibility during workload distribution. Even though, controllers are flexible and scalable to accommodate more number of network switches, yet the problem of intercommunication cost between distributed controllers is still challenging issue in the Software Defined Network environment. This paper, aims to fill the gap by proposing a new mechanism, which minimizes intercommunication cost with graph partitioning algorithm, an NP hard problem. The methodology proposed in this paper is, swapping of network elements between controller domains to minimize communication cost by calculating communication gain. The swapping of elements minimizes inter and intra communication cost among network domains. We validate our work with the OMNeT++ simulation environment tool. Simulation results show that the proposed mechanism minimizes the inter domain communication cost among controllers compared to traditional distributed controllers.

  8. Understanding Team Communication Characteristics using Social Network Analysis

    International Nuclear Information System (INIS)

    An important aspect of human behavior in nuclear power plants (NPPs) is team interaction since operating NPPs involves the coordination of several team members among and within workplaces. Since operators in main control room (MCR) get a great deal of information through communication to perform a task, communication is one of the important characteristics for team characteristics. Many researchers have been studying how to understand the characteristics of communication. Social network analysis (SNA) which is considered as an objective and easily applicable method has been already applied in many fields to investigate characteristics of team communication. Henttonen (2010) has struggled to perform the research on the impact of social networks in a team and he found some team communication characteristics could be obtained using some properties of SNA. In this paper, SNA is used to understand communication characteristics within operators in NPPs

  9. Design of Hybrid Mobile Communication Networks for Planetary Exploration

    Science.gov (United States)

    Alena, Richard L.; Ossenfort, John; Lee, Charles; Walker, Edward; Stone, Thom

    2004-01-01

    The Mobile Exploration System Project (MEX) at NASA Ames Research Center has been conducting studies into hybrid communication networks for future planetary missions. These networks consist of space-based communication assets connected to ground-based Internets and planetary surface-based mobile wireless networks. These hybrid mobile networks have been deployed in rugged field locations in the American desert and the Canadian arctic for support of science and simulation activities on at least six occasions. This work has been conducted over the past five years resulting in evolving architectural complexity, improved component characteristics and better analysis and test methods. A rich set of data and techniques have resulted from the development and field testing of the communication network during field expeditions such as the Haughton Mars Project and NASA Mobile Agents Project.

  10. Advanced communication and network requirements in Europe

    DEFF Research Database (Denmark)

    Falch, Morten; Enemark, Rasmus

    The report address diffusion of new tele-application, focusing on potential use and potential tele-trafic genrated as a consequense. The applications investigated are: Teleworking, distance learning, research and university network, applications aimed at SMEs, health networks, a trans European...... public administation network, city information highway, road-trafic manegement, air traffic control and electronic quotation....

  11. Analyzing Human Communication Networks in Organizations: Applications to Management Problems.

    Science.gov (United States)

    Farace, Richard V.; Danowski, James A.

    Investigating the networks of communication in organizations leads to an understanding of efficient and inefficient information dissemination as practiced in large systems. Most important in organizational communication is the role of the "liaison person"--the coordinator of intercommunication. When functioning efficiently, coordinators maintain…

  12. TCP-IP Model in Data Communication and Networking

    Directory of Open Access Journals (Sweden)

    Pranab Bandhu Nath

    2015-10-01

    Full Text Available The Internet protocol suite is the computer networking model and set of communications protocols used on the Internet and similar computer networks. It is commonly known as TCP/IP, because it’s most important protocols, the Transmission Control Protocol (TCP and the Internet Protocol (IP, were the first networking protocols defined in this standard. Often also called the Internet model, it was originally also known as the DoD model, because the development of the networking model was funded by DARPA, an agency of the United States Department of Defense. TCP/IP provides end-to-end connectivity specifying how data should be packetized, addressed, transmitted, routed and received at the destination. This functionality is organized into four abstraction layers which are used to sort all related protocols according to the scope of networking involved. From lowest to highest, the layers are the link layer, containing communication technologies for a single network segment (link; the internet layer, connecting hosts across independent networks, thus establishing internetworking; the transport layer handling host-to-host communication; and the application layer, which provides process-to-process application data exchange. Our aim is describe operation & models of TCP-IP suite in data communication networking

  13. Green Networking for Major Components of Information Communication Technology Systems

    Directory of Open Access Journals (Sweden)

    Zeadally Sherali

    2009-01-01

    Full Text Available Abstract Green Networking can be the way to help reduce carbon emissions by the Information and Communications Technology (ICT Industry. This paper presents some of the major components of Green Networking and discusses how the carbon footprint of these components can be reduced.

  14. Comparative Analysis of Human Communication Networks in Selected Formal Organizations.

    Science.gov (United States)

    Farace, Richard V.; Johnson, Jerome David

    This paper briefly describes the organization of a "data bank" containing research on communication networks, specifies the kinds of information compiled about various network properties, discusses some specific results of the work done to date, and presents some general conclusions about the overall project and its potential advantages to…

  15. Communications network design and costing model programmers manual

    Science.gov (United States)

    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.

  16. Communications network design and costing model users manual

    Science.gov (United States)

    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.

  17. Seamless integrated network system for wireless communication systems

    NARCIS (Netherlands)

    Wu, Gang; Mizuno, Mitsuhiko; Hase, Yoshihiro; Havinga, Paul J.M.

    2006-01-01

    To create a network that connects a plurality of wireless communication systems to create optimal systems for various environments, and that seamlessly integrates the resulting systems together in order to provide more efficient and advanced service in general. A network system that can seamlessly i

  18. Seamless integrated network system for wireless communication systems

    NARCIS (Netherlands)

    Wu, Gang; Mizuno, Mitsuhiko; Hase, Yoshihiro; Havinga, Paul J.M.

    2002-01-01

    To create a network that connects a plurality of wireless communication systems to create optimal systems for various environments, and that seamlessly integrates the resulting systems together in order to provide more efficient and advanced service in general. A network system that can seamlessly i

  19. Quantum Secure Direct Communication Network with Two-Step Protocol

    Institute of Scientific and Technical Information of China (English)

    LI Xi-Han; ZHOU Ping; LIANG Yu-Jie; LI Chun-Yan; ZHOU Hong-Yu; DENG Fu-Guo

    2006-01-01

    @@ An efficient quantum secure direct communication network protocol with the two-step scheme is proposed by using the Einstein-Podolsky-Rosen (EPR) pair block as the quantum information carrier. The server, say Alice,prepares and measures the EPR pairs in the quantum communication and the users perform the four local unitary operations to encode their message. Anyone of the legitimate users can communicate another one on the network securely. Since almost all of the instances in this scheme are useful and each EPR pair can carry two bits of information, the efficiency for qubits and the source capacity both approach the maximal values.

  20. Existence of outsiders as a characteristic of online communication networks

    CERN Document Server

    Takaguchi, Taro; Toyoda, Masashi; Kawarabayashi, Ken-ichi

    2014-01-01

    Online social networking services (SNSs) involve communication activities between large number of individuals over the public Internet and their crawled records are often regarded as proxies of real (i.e., offline) interaction structure. However, structure observed in these records might differ from real counterparts because individuals may behave differently online and non-human accounts may even participate. To understand the difference between online and real social networks, we investigate an empirical communication network between users on Twitter, which is perhaps one of the largest SNSs. We define a network of user pairs that send reciprocal messages. Based on the mixing pattern observed in this network, we argue that this network differs from conventional understandings in the sense that there is a small number of distinctive users that we call outsiders. Outsiders do not belong to any user groups but they are connected with different groups, while not being well connected with each other. We identify...

  1. The Impact of Network Advertising and Marketing for the Automotive Industry%网络广告营销对汽车行业的影响

    Institute of Scientific and Technical Information of China (English)

    李昉

    2014-01-01

    Automotive network advertising and marketing as the automotive industry and Internet industry product of the combination of rapid growth, much favored by the majority of car manufacturers in the market was a great success. Expounds the role in the Internet era, online advertising in the automotive industry, and also separately from the status quo, Problems and Development Strategies tripartite existence in the face of the automotive industry marketing, online advertising is analyzed.%汽车网络广告营销作为高速发展的汽车产业和互联网产业结合的产物,备受广大汽车制造商的青睐,在市场上获得了巨大的成功。主要阐述了在互联网时代,网络广告在汽车行业中的作用,还分别从发展现状、存在的问题和发展对策三方面对汽车行业网络广告营销进行了分析。

  2. 网络广告营销对汽车行业的影响%The Impact of Network Advertising and Marketing for the Automotive Industry

    Institute of Scientific and Technical Information of China (English)

    李昉

    2014-01-01

    汽车网络广告营销作为高速发展的汽车产业和互联网产业结合的产物,备受广大汽车制造商的青睐,在市场上获得了巨大的成功。主要阐述了在互联网时代,网络广告在汽车行业中的作用,还分别从发展现状、存在的问题和发展对策三方面对汽车行业网络广告营销进行了分析。%Automotive network advertising and marketing as the automotive industry and Internet industry product of the combination of rapid growth, much favored by the majority of car manufacturers in the market was a great success. Expounds the role in the Internet era, online advertising in the automotive industry, and also separately from the status quo, Problems and Development Strategies tripartite existence in the face of the automotive industry marketing, online advertising is analyzed.

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

    Directory of Open Access Journals (Sweden)

    Michael D Conover

    Full Text Available 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.

  4. 2nd International Conference on Green Communications and Networks 2012

    CERN Document Server

    Ma, Maode; GCN 2012

    2013-01-01

    The objective of the 2nd International Conference on Green Communications and Networks 2012 (GCN 2012) is to facilitate an exchange of information on best practices for the latest research advances in the area of communications, networks and intelligence applications. These mainly involve computer science and engineering, informatics, communications and control, electrical engineering, information computing, and business intelligence and management. Proceedings of the 2nd International Conference on Green Communications and Networks 2012 (GCN 2012) will focus on green information technology and applications, which will provide in-depth insights for engineers and scientists in academia, industry, and government. The book addresses the most innovative research developments including technical challenges, social and economic issues, and presents and discusses the authors’ ideas, experiences, findings, and current projects on all aspects of advanced green information technology and applications. Yuhang Yang is ...

  5. Routing Protocol for Anycast Communications in a Wireless Sensor Network

    OpenAIRE

    Rachkidy, Nancy; Guitton, Alexandre; Misson, Michel

    2010-01-01

    International audience In wireless sensor networks, there is usually a sink which gathers data from the battery-powered sensor nodes. As sensor nodes around the sink consume their energy faster than the other nodes, several sinks have to be deployed to increase the network lifetime. In this paper, we motivate the need of anycast communications in wireless networks, where all the sinks are identical and can gather data from any source. To reduce interference and congestion areas on the wire...

  6. Space Mobile Network: A Near Earth Communication and Navigation Architecture

    Science.gov (United States)

    Israel, Dave J.; Heckler, Greg; Menrad, Robert J.

    2016-01-01

    This paper describes a Space Mobile Network architecture, the result of a recently completed NASA study exploring architectural concepts to produce a vision for the future Near Earth communications and navigation systems. The Space Mobile Network (SMN) incorporates technologies, such as Disruption Tolerant Networking (DTN) and optical communications, and new operations concepts, such as User Initiated Services, to provide user services analogous to a terrestrial smartphone user. The paper will describe the SMN Architecture, envisioned future operations concepts, opportunities for industry and international collaboration and interoperability, and technology development areas and goals.

  7. Wireless Network Communications Overview for Space Mission Operations

    Science.gov (United States)

    Fink, Patrick W.

    2009-01-01

    The mission of the On-Board Wireless Working Group (WWG) is to serve as a general CCSDS focus group for intra-vehicle wireless technologies. The WWG investigates and makes recommendations pursuant to standardization of applicable wireless network protocols, ensuring the interoperability of independently developed wireless communication assets. This document presents technical background information concerning uses and applicability of wireless networking technologies for space missions. Agency-relevant driving scenarios, for which wireless network communications will provide a significant return-on-investment benefiting the participating international agencies, are used to focus the scope of the enclosed technical information.

  8. Quantum Communication Through a Two-Dimensional Spin Network

    Institute of Scientific and Technical Information of China (English)

    王兆明; 顾永建

    2012-01-01

    We investigate the state or entanglement transfer through a two-dimensional spin network. We show that for state transfer, better fidelity can be gained along the diagonal direction but for entanglement transfer, when the initial entanglement is created along the boundary, the concurrence is more inclined to propagate along the boundary. This behavior is produced by quantum mechanical interference and the communication quality depends on the precise size of the network. For some number of sites, the fidelity in a two-dimensional channel is higher than one-dimensional case. This is an important result for realizing quantum communication through high dimension spin chain networks.

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

    Science.gov (United States)

    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.

  10. A Novel Routing Strategy on Space Communication Network

    Science.gov (United States)

    LI, Yujian; WANG, Xu-Liang; Zhen-dong, XI; Bing-hong, WANG

    2016-02-01

    In this paper, we propose an effective routing strategy on the basis of the so-called nearest neighbor search strategy by introducing a preferential time delay exponent β. Traffic dynamics both near and far away from the critical generating rate Rc are discussed. Simulation results demonstrate that the optimal performance of the system corresponds to β =-0.5. Due to the low cost of acquiring nearest-neighbor information and the strongly improved network capacity, our strategy may be useful and reasonable for the protocol designing of modern communication networks and space communication networks.

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

    Science.gov (United States)

    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.

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

    CERN Document Server

    Estrada, Ernesto

    2013-01-01

    We analyse 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.

  13. Extended master equation models for molecular communication networks.

    Science.gov (United States)

    Chou, Chun Tung

    2013-06-01

    We consider molecular communication networks consisting of transmitters and receivers distributed in a fluidic medium. In such networks, a transmitter sends one or more signaling molecules, which are diffused over the medium, to the receiver to realize the communication. In order to be able to engineer synthetic molecular communication networks, mathematical models for these networks are required. This paper proposes a new stochastic model for molecular communication networks called reaction-diffusion master equation with exogenous input (RDMEX). The key idea behind RDMEX is to model the transmitters as time series of signaling molecule counts, while diffusion in the medium and chemical reactions at the receivers are modeled as Markov processes using master equation. An advantage of RDMEX is that it can readily be used to model molecular communication networks with multiple transmitters and receivers. For the case where the reaction kinetics at the receivers is linear, we show how RDMEX can be used to determine the mean and covariance of the receiver output signals, and derive closed-form expressions for the mean receiver output signal of the RDMEX model. These closed-form expressions reveal that the output signal of a receiver can be affected by the presence of other receivers. Numerical examples are provided to demonstrate the properties of the model.

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

    Science.gov (United States)

    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

  15. AntNet: Distributed Stigmergetic Control for Communications Networks

    CERN Document Server

    Di Caro, G

    2011-01-01

    This paper introduces AntNet, a novel approach to the adaptive learning of routing tables in communications networks. AntNet is a distributed, mobile agents based Monte Carlo system that was inspired by recent work on the ant colony metaphor for solving optimization problems. AntNet's agents concurrently explore the network and exchange collected information. The communication among the agents is indirect and asynchronous, mediated by the network itself. This form of communication is typical of social insects and is called stigmergy. We compare our algorithm with six state-of-the-art routing algorithms coming from the telecommunications and machine learning fields. The algorithms' performance is evaluated over a set of realistic testbeds. We run many experiments over real and artificial IP datagram networks with increasing number of nodes and under several paradigmatic spatial and temporal traffic distributions. Results are very encouraging. AntNet showed superior performance under all the experimental condit...

  16. Power, Avionics and Software Communication Network Architecture

    Science.gov (United States)

    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).

  17. Training resonant communicators. From raining resonant communicators. From neural networks to network society

    Directory of Open Access Journals (Sweden)

    Gotzon Toral Madariaga

    2013-02-01

    Full Text Available 0 0 1 121 669 USAL 5 1 789 14.0 Normal 0 21 false false false ES JA X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Tabla normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin-top:0cm; mso-para-margin-right:0cm; mso-para-margin-bottom:10.0pt; mso-para-margin-left:0cm; line-height:115%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:Calibri; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-ansi-language:ES; mso-fareast-language:EN-US;} Media control is no longer exclusively in the hands of professional broadcasters. New educational projects must empower users so that they can exercise their digital citizenship. As well as acquiring essential technical skills to move in an interconnected world, emotional literacy is also indispensable for people to desire to take part effectively in this augmented community. So, besides teaching audiovisual technology, this project seeks to re-program the relationship that students develop with a situation that is typically stressful. We propose an expanded practice that enables students to recognize and voluntarily activate their communication biology. This way, users can become actors in new communication networks, and global communication flow will be more plural and richer.

  18. Enhanced Communication Network Solution for Positive Train Control Implementation

    Science.gov (United States)

    Fatehi, M. T.; Simon, J.; Chang, W.; Chow, E. T.; Burleigh, S. C.

    2011-01-01

    The commuter and freight railroad industry is required to implement Positive Train Control (PTC) by 2015 (2012 for Metrolink), a challenging network communications problem. This paper will discuss present technologies developed by the National Aeronautics and Space Administration (NASA) to overcome comparable communication challenges encountered in deep space mission operations. PTC will be based on a new cellular wireless packet Internet Protocol (IP) network. However, ensuring reliability in such a network is difficult due to the "dead zones" and transient disruptions we commonly experience when we lose calls in commercial cellular networks. These disruptions make it difficult to meet PTC s stringent reliability (99.999%) and safety requirements, deployment deadlines, and budget. This paper proposes innovative solutions based on space-proven technologies that would help meet these challenges: (1) Delay Tolerant Networking (DTN) technology, designed for use in resource-constrained, embedded systems and currently in use on the International Space Station, enables reliable communication over networks in which timely data acknowledgments might not be possible due to transient link outages. (2) Policy-Based Management (PBM) provides dynamic management capabilities, allowing vital data to be exchanged selectively (with priority) by utilizing alternative communication resources. The resulting network may help railroads implement PTC faster, cheaper, and more reliably.

  19. Efficient data communication protocols for wireless networks

    Science.gov (United States)

    Zeydan, Engin

    In this dissertation, efficient decentralized algorithms are investigated for cost minimization problems in wireless networks. For wireless sensor networks, we investigate both the reduction in the energy consumption and throughput maximization problems separately using multi-hop data aggregation for correlated data in wireless sensor networks. The proposed algorithms exploit data redundancy using a game theoretic framework. For energy minimization, routes are chosen to minimize the total energy expended by the network using best response dynamics to local data. The cost function used in routing takes into account distance, interference and in-network data aggregation. The proposed energy-efficient correlation-aware routing algorithm significantly reduces the energy consumption in the network and converges in a finite number of steps iteratively. For throughput maximization, we consider both the interference distribution across the network and correlation between forwarded data when establishing routes. Nodes along each route are chosen to minimize the interference impact in their neighborhood and to maximize the in-network data aggregation. The resulting network topology maximizes the global network throughput and the algorithm is guaranteed to converge with a finite number of steps using best response dynamics. For multiple antenna wireless ad-hoc networks, we present distributed cooperative and regret-matching based learning schemes for joint transmit beanformer and power level selection problem for nodes operating in multi-user interference environment. Total network transmit power is minimized while ensuring a constant received signal-to-interference and noise ratio at each receiver. In cooperative and regret-matching based power minimization algorithms, transmit beanformers are selected from a predefined codebook to minimize the total power. By selecting transmit beamformers judiciously and performing power adaptation, the cooperative algorithm is shown to

  20. Entrepreneurial networking in supply chain relationships in the automotive component industry

    OpenAIRE

    R. C. O’Neill; M. J. Naude

    2011-01-01

    Purpose: The point of departure in this article is that the principles that underpin entrepreneurial networking also apply to the establishment of supply chain relationships. The theoretical base for the need for entrepreneurial networking can be found in Kirzner's theory of entrepreneurship that argued that entrepreneurs identify and act upon profit opportunities that exist in disequilibrium in order to equilibrate the economy. Problem investigated: This article explores the possibility...

  1. Northern emporia and maritime networks. Modelling past communication using archaeological network analysis

    DEFF Research Database (Denmark)

    Sindbæk, Søren Michael

    2015-01-01

    Long-distance communication has emerged as a particular focus for archaeologicalexploration using network theory, analysis, and modelling. The promise is apparentlyobvious: communication in the past doubtlessly had properties of complex, dynamicnetworks, and archaeological datasets almost certainly...... this is not a problem of network analysis, but network synthesis: theclassic problem of cracking codes or reconstructing black-box circuits. It is proposedthat archaeological approaches to network synthesis must involve a contextualreading of network data: observations arising from individual contexts, morphologies...... preserve patterns of thisinteraction. Formal network analysis and modelling holds the potential to identify anddemonstrate such patterns, where traditional methods often prove inadequate. Thearchaeological study of communication networks in the past, however, calls for radically different analytical...

  2. Ninth International Conference on Wireless Communication and Sensor Networks

    CERN Document Server

    Tiwari, Murlidhar; Arora, Anish

    2014-01-01

    Wireless communication and sensor networks would form the backbone to create pervasive and ubiquitous environments that would have profound influence on the society and thus are important to the society. The wireless communication technologies and wireless sensor networks would encompass a wide range of domains such as HW devices such as motes, sensors and associated instrumentation, actuators, transmitters, receivers, antennas, etc., sensor network aspects such as topologies, routing algorithms, integration of heterogeneous network elements and topologies, designing RF devices and systems for energy efficiency and reliability etc. These sensor networks would provide opportunity to continuously and in a distributed manner monitor the environment and generate the necessary warnings and actions. However most of the developments have been demonstrated only in controlled and laboratory environments. So we are yet to see those powerful, ubiquitous applications for the benefit of the society. The conference and con...

  3. Framework for Efficient Secure Steganographic Communication over Network Protocols

    Directory of Open Access Journals (Sweden)

    Jasbir Singh

    2013-12-01

    Full Text Available Security by obscurity has gained attention; as a result steganography is becoming more popular in the network communication. Network steganography describes various methods used for transmitting data over a network without it being detected. Most of the methods proposed for hiding data in a network do not offer an additional protection to the covert data as it is sent as plain text. This paper presents a framework that offers the protection to the covert data by encrypting it and compresses it for gain in efficiency. Several ways of sending covert information through network using TCP/IP protocol are discussed. Also, the communication made more secure and efficient by using compression and encryption techniques. Finally, the performance of the proposed framework is compared with other steganography tools.

  4. Control of communication networks: welfare maximization and multipath transfers.

    Science.gov (United States)

    Key, Peter B; Massoulié, Laurent

    2008-06-13

    We discuss control strategies for communication networks such as the Internet. We advocate the goal of welfare maximization as a paradigm for network resource allocation. We explore the application of this paradigm to the case of parallel network paths. We show that welfare maximization requires active balancing across paths by data sources, and potentially requires implementation of novel transport protocols. However, the only requirement from the underlying 'network layer' is to expose the marginal congestion cost of network paths to the 'transport layer'. We further illustrate the versatility of the corresponding layered architecture by describing transport protocols with the following properties: they welfare maximization, each communication may use an arbitrary collection of paths, where paths may be from an overlay, and paths may be combined in series and parallel. We conclude by commenting on incentives, pricing and open problems. PMID:18325871

  5. Networked Control Systems: The Communication Basics and Control Methodologies

    Directory of Open Access Journals (Sweden)

    Yun-Bo Zhao

    2015-01-01

    Full Text Available As an emerging research field, networked control systems have shown the increasing importance and attracted more and more attention in the recent years. The integration of control and communication in networked control systems has made the design and analysis of such systems a great theoretical challenge for conventional control theory. Such an integration also makes the implementation of networked control systems a necessary intermediate step towards the final convergence of control, communication, and computation. We here introduce the basics of networked control systems and then describe the state-of-the-art research in this field. We hope such a brief tutorial can be useful to inspire further development of networked control systems in both theory and potential applications.

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

    Science.gov (United States)

    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.

  7. V2V Communication Survey - (Wireless Technology)

    OpenAIRE

    Vaishali D. Khairnar; Pradhan, Dr. S. N.

    2012-01-01

    This paper presents the specific application of wireless communication, Automotive Wireless Communication_ also called as Vehicle-to-Vehicle Communication. The paper first gives an introduction to the Automotive Wireless Communication. It explains the technology used for Automotive Wireless Communication along with the various automotive applications relying on wireless communication. Automotive Wireless Communication gives drivers a sixth sense to know what’s going on around them to help avo...

  8. Hierarchical Communication Network Architectures for Offshore Wind Power Farms

    Directory of Open Access Journals (Sweden)

    Mohamed A. Ahmed

    2014-05-01

    Full Text Available Nowadays, large-scale wind power farms (WPFs bring new challenges for both electric systems and communication networks. Communication networks are an essential part of WPFs because they provide real-time control and monitoring of wind turbines from a remote location (local control center. However, different wind turbine applications have different requirements in terms of data volume, latency, bandwidth, QoS, etc. This paper proposes a hierarchical communication network architecture that consist of a turbine area network (TAN, farm area network (FAN, and control area network (CAN for offshore WPFs. The two types of offshore WPFs studied are small-scale WPFs close to the grid and medium-scale WPFs far from the grid. The wind turbines are modelled based on the logical nodes (LN concepts of the IEC 61400-25 standard. To keep pace with current developments in wind turbine technology, the network design takes into account the extension of the LNs for both the wind turbine foundation and meteorological measurements. The proposed hierarchical communication network is based on Switched Ethernet. Servers at the control center are used to store and process the data received from the WPF. The network architecture is modelled and evaluated via OPNET. We investigated the end-to-end (ETE delay for different WPF applications. The results are validated by comparing the amount of generated sensing data with that of received traffic at servers. The network performance is evaluated, analyzed and discussed in view of end-to-end (ETE delay for different link bandwidths.

  9. VIRTUAL NETWORK COMMUNICATION AND ITS IMPACT ON INTERPERSONAL RELATIONS

    Directory of Open Access Journals (Sweden)

    Сергей Николаевич Хуторной

    2013-08-01

    Full Text Available The Internet was playing an increasing role in human life. Increasingly popular sites, where visitors can interact with other visitors through this site. Becoming popular communication "online", partially displacing the real-мире. There arises a problem of Internet addiction, or dependence on the Internet, which includes not only the dependence on virtual communication in social networks, but also addiction to gambling, online games, electronic purchases, and so on. Virtual reality acts not only as an intermediary virtual communication, but also significantly affect the nature, means and methods of communication, which ultimately has a significant effect on identity, often negatively, transforming it. The article dedicated to the analysis  of intercourse in virtual reality. The specification of net communication in comparing of real social communication is researching. The concept of Internet addicion is examined.DOI: http://dx.doi.org/10.12731/2218-7405-2013-6-9

  10. An exploration of the strategic implementation of marketing communication within social networking communication context

    OpenAIRE

    Cloete, Ewoudt

    2012-01-01

    Taking into consideration the dramatic changes ushered in by the exponential growth of social networking, marketers are left without a dependable framework on how to implement social networking strategically and in alignment with other modern as well as traditional marketing disciplines. In light of this, the study aims to explore the strategic implementation of social networking within the context of a dependable marketing theoretical model, known as the marketing communications mix. D...

  11. Reliable Communication in Wireless Meshed Networks using Network Coding

    DEFF Research Database (Denmark)

    Pahlevani, Peyman; Paramanathan, Achuthan; Hundebøll, Martin;

    2012-01-01

    The advantages of network coding have been extensively studied in the field of wireless networks. Integrating network coding with existing IEEE 802.11 MAC layer is a challenging problem. The IEEE 802.11 MAC does not provide any reliability mechanisms for overheard packets. This paper addresses...... this problem and suggests different mechanisms to support reliability as part of the MAC protocol. Analytical expressions to this problem are given to qualify the performance of the modified network coding. These expressions are confirmed by numerical result. While the suggested reliability mechanisms...

  12. Assessing the Bias in Communication Networks Sampled from Twitter

    CERN Document Server

    González-Bailón, Sandra; Rivero, Alejandro; Borge-Holthoefer, Javier; Moreno, Yamir

    2012-01-01

    We collect and analyse messages exchanged in Twitter using two of the platform's publicly available APIs (the search and stream specifications). We assess the differences between the two samples, and compare the networks of communication reconstructed from them. The empirical context is given by political protests taking place in May 2012: we track online communication around these protests for the period of one month, and reconstruct the network of mentions and re-tweets according to the two samples. We find that the search API over-represents the more central users and does not offer an accurate picture of peripheral activity; we also find that the bias is greater for the network of mentions. We discuss the implications of this bias for the study of diffusion dynamics and collective action in the digital era, and advocate the need for more uniform sampling procedures in the study of online communication.

  13. Future cooperative communication systems driven by social mobile networks

    DEFF Research Database (Denmark)

    Blázovics, L.; Varga, C.; Bamford, W.;

    2011-01-01

    In this work we are underlining the importance of social mobile networks for upcoming cooperative communication systems. The assumption of this work is that future mobile communication systems will incorporate user cooperation, i.e. a combination of cellular access in parallel with ongoing short...... range links to the neighboring devices. It has been shown that user cooperation enables higher data rates, better spectral efficiencies, and reduces the energy consumption of the mobile unit. In this work the social mobile networks are identified to be a fertile ground to facilitate the cooperative use...... cases. By the example of the Gedda-Headz gaming community, possible links between cooperative mobile communication and social mobile networks are shown....

  14. Doubly Optimal Secure Multicasting: Hierarchical Hybrid Communication Network : Disaster Relief

    CERN Document Server

    Garimella, Rama Murthy; Singhal, Deepti

    2011-01-01

    Recently, the world has witnessed the increasing occurrence of disasters, some of natural origin and others caused by man. The intensity of the phenomenon that cause such disasters, the frequency in which they occur, the number of people affected and the material damage caused by them have been growing substantially. Disasters are defined as natural, technological, and human-initiated events that disrupt the normal functioning of the economy and society on a large scale. Areas where disasters have occurred bring many dangers to rescue teams and the communication network infrastructure is usually destroyed. To manage these hazards, different wireless technologies can be launched in the area of disaster. This paper discusses the innovative wireless technologies for Disaster Management. Specifically, issues related to the design of Hierarchical Hybrid Communication Network (arising in the communication network for disaster relief) are discussed.

  15. Capacity gain with an alternative LTE railway communication network

    DEFF Research Database (Denmark)

    Sniady, Aleksander; Soler, José

    2014-01-01

    GSM - Railways (GSM - R) is the first international communication network designed specifically for railway s. Most of the deployed GSM - R networks were initially used only to provide the railway voice communication. However, as more of these GSM - R networks begin to support the European Train...... Control System (ETCS) signaling , the capacity of GSM - R turns out to be insufficient . GSM - R cannot ful fill the railway requirements , in terms of the number of simultaneous ETCS connections . This is why , alternative , more efficient communication technologies should be considered by railways....... Usin g this model , LTE and GSM - R are compare d in terms of capacity on an example at Copenhagen Main Train Station . The purpose of this work is to demonstrate the benefits that railway operators and infrastructure managers can expect from the introduc tion of LTE , as a telecommunication technology...

  16. An Anonymous Authentication and Communication Protocol for Wireless Mesh Networks

    CERN Document Server

    Sen, Jaydip

    2011-01-01

    Wireless mesh networks (WMNs) have emerged as a key technology for next generation wireless broadband networks showing rapid progress and inspiring numerous compelling applications. A WMN comprises of a set of mesh routers (MRs) and mesh clients (MCs), where MRs are connected to the Internet backbone through the Internet gateways (IGWs). The MCs are wireless devices and communicate among themselves over possibly multi-hop paths with or without the involvement of MRs. User privacy and security have been primary concerns in WMNs due to their peer-to-peer network topology, shared wireless medium, stringent resource constraints, and highly dynamic environment. Moreover, to support real-time applications, WMNs must also be equipped with robust, reliable and efficient communication protocols so as to minimize the end-to-end latency and packet drops. Design of a secure and efficient communication protocol for WMNs, therefore, is of paramount importance. In this paper, we propose a security and privacy protocol that ...

  17. Advanced information processing system: Authentication protocols for network communication

    Science.gov (United States)

    Harper, Richard E.; Adams, Stuart J.; Babikyan, Carol A.; Butler, Bryan P.; Clark, Anne L.; Lala, Jaynarayan H.

    1994-01-01

    In safety critical I/O and intercomputer communication networks, reliable message transmission is an important concern. Difficulties of communication and fault identification in networks arise primarily because the sender of a transmission cannot be identified with certainty, an intermediate node can corrupt a message without certainty of detection, and a babbling node cannot be identified and silenced without lengthy diagnosis and reconfiguration . Authentication protocols use digital signature techniques to verify the authenticity of messages with high probability. Such protocols appear to provide an efficient solution to many of these problems. The objective of this program is to develop, demonstrate, and evaluate intercomputer communication architectures which employ authentication. As a context for the evaluation, the authentication protocol-based communication concept was demonstrated under this program by hosting a real-time flight critical guidance, navigation and control algorithm on a distributed, heterogeneous, mixed redundancy system of workstations and embedded fault-tolerant computers.

  18. Securing Communication in Ambient Networks for Speech Therapy Systems

    Directory of Open Access Journals (Sweden)

    ZAHARIA, M. H.

    2007-11-01

    Full Text Available One of the most present issues of computer wireless networks is the security. Comparing with their wired counterpart, the wireless networks not only accentuate some of the well-known security vulnerabilities but they are subject of new and specific ones. Among the existing wireless networks the ad hoc ones are the most exposed to attacks and collusions due to the absence of any centralized control. The most efficient way to ensure the communication secrecy, inclusively for ad hoc wireless networks, is the cryptography. From many reasons, following from specific operating conditions, the employment of asymmetric key techniques and Public Key Infrastructure is not a realistic choice. In the networks with a large number of nodes, as wireless sensor networks, a large number of secret keys are involved in order to ensure the communication secrecy. While dynamicity is one of the essential features of mobile wireless networks, when nodes may leave or join the network and in the absence of a centralized control entity, the management of secret keys is crucial. The paper presents the main aspects of mobile wireless networks security and focuses on the key management issue in ad-hoc wireless networks.In this paper the problem of securing mobile devices used in ambient networks for speech therapy is presented. The main target consists in making various mobile devices involved in speech therapy to maintain both the confidentiality of personal data of the patient and also to avoid interference when simultaneous communicate with the control center. Due to non-technical type of user all password management will be made automatic by the control system. As result the mobile device will have a user transparent security layer added. The problem of people from isolated community treatment is also solved by this approach.

  19. Industrial communication technology handbook

    CERN Document Server

    Zurawski, Richard

    2014-01-01

    Featuring contributions from major technology vendors, industry consortia, and government and private research establishments, the Industrial Communication Technology Handbook, Second Edition provides comprehensive and authoritative coverage of wire- and wireless-based specialized communication networks used in plant and factory automation, automotive applications, avionics, building automation, energy and power systems, train applications, and more.New to the Second Edition:46 brand-new chapters and 21 substantially revised chaptersInclusion of the latest, most significant developments in spe

  20. A Communication network for LHC detector readout

    Energy Technology Data Exchange (ETDEWEB)

    Romero, L.

    1993-07-01

    This paper describe a network architecture for data taking in LHC environment. The network is composed of 64 rings of point to point links working at 100 Mbytes/s. The network connect the front end electronics, computer farms and two data switches. The efficiency of the system is discussed. Using extracted 1 Kbyte events for the 2nd level trigger and whole 1 Mbyte events for the 3rd level trigger, then the system can sustain working rates of 2 x 10''5 and 2 x 10''3 events/s going into the 2nd and 3rd level triggers. System resistance to errors is discussed. (Author) 3 refs.

  1. Intelligent Vertical Handoffs between Heterogeneous Communication Networks

    Institute of Scientific and Technical Information of China (English)

    ZHANG Qi; WANG Yi-hong; VICTOR O.K.; WANG Ying; ZHANG Ping

    2005-01-01

    This paper proposes an intelligent vertical handoff algorithm to maintain an ongoing call between a cellular mobile network and a Wireless Local Area Network (WLAN), based on the Received Signal Strength (RSS) threshold and an adaptive RSS hysteresis generated by fuzzy logic. In addition, the proposed algorithm accounts for the WLAN traffic loading and the direction of movement and speed of the Mobile Station (MS). Simulation results indicate that the proposed algorithm offers better system performance in terms of number of handoffs and probability of call dropping.

  2. Network Coding Protocols for Smart Grid Communications

    DEFF Research Database (Denmark)

    Prior, Rui; Roetter, Daniel Enrique Lucani; Phulpin, Yannick;

    2014-01-01

    We propose a robust network coding protocol for enhancing the reliability and speed of data gathering in smart grids. At the heart of our protocol lies the idea of tunable sparse network coding, which adopts the transmission of sparsely coded packets at the beginning of the transmission process...... but then switches to a denser coding structure towards the end. Our systematic mechanism maintains the sparse structure during the recombination of packets at the intermediate nodes. The performance of our protocol is compared by means of simulations of IEEE reference grids against standard master-slave protocols...

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

    Science.gov (United States)

    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.

  4. Energy Constrained Wireless Sensor Networks : Communication Principles and Sensing Aspects

    OpenAIRE

    Björnemo, Erik

    2009-01-01

    Wireless sensor networks are attractive largely because they need no wired infrastructure. But precisely this feature makes them energy constrained, and the consequences of this hard energy constraint are the overall topic of this thesis. We are in particular concerned with principles for energy efficient wireless communication and the energy-wise trade-off between sensing and radio communication. Radio transmission between sensors incurs both a fixed energy cost from radio circuit processing...

  5. Compensating for Unreliable Communication Links in Networked Control Systems

    OpenAIRE

    Henriksson, Erik

    2009-01-01

    Control systems utilizing wireless sensor and actuator networks can be severely affectedby the properties of the communication links. Radio fading and interferencemay cause communication losses and outages in situations when the radio environmentis noisy and low transmission power is desirable. This thesis proposes amethod to compensate for such unpredictable losses of data in the feedback controlloop by introducing a predictive outage compensator (POC). The POC is a filter tobe implemented a...

  6. A supervisory control policy over an acoustic communication network

    OpenAIRE

    Farhadi, Alireza; Dumon, Jonathan; Canudas-De-Wit, Carlos

    2014-01-01

    International audience This paper presents a supervisory multi-agent control policy over an acoustic communication network subject to imperfections (packet dropout and transmission delay) for localization of an underwater flow source (e.g., source of chemical pollution, fresh water, etc.) with an unknown location at the bottom of the ocean. A two-loop control policy combined with a coding strategy for reliable communication is presented to perform the above task. A simulator is developed a...

  7. First-Use Analysis of Communication in a Social Network

    Science.gov (United States)

    Itaya, Satoko; Yoshinaga, Naoki; Davis, Peter; Tanaka, Rie; Konishi, Taku; Doi, Shinich; Yamada, Keiji

    The study of communication activity in social networks is aimed at understanding and promoting communications in groups, organizations and communities. In this paper, we propose a method for the analysis of communication records to extract content-based network activity, with a focus on first-use. Links between people in a social network are defined based on content and temporal relation of messages sent and received. We introduce the notion of first-use, first-use paths, and classes of users based on first-usage. First-use is defined with respect to a specific time period and specific communication content. It refers to the sending of messages containing the specified contents for the first time before being receiving them from any other user in the specified time period. First-use paths are defined as sequences of first-use events in communication networks, and m-ary classes of users are defined recursively as users who receive for the first time from (m-1)-ary users. We present an example of application of the analysis to the email records of a large company.

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

    Science.gov (United States)

    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.

  9. Asymmetrical Modulation for Uplink Communication in Cooperative Networks

    DEFF Research Database (Denmark)

    Zhang, Qi; Fitzek, Frank H.P.; Iversen, Villy Bæk

    2008-01-01

    In this paper a spectrum efficient uplink communication method for cooperative wireless networks is presented. In cellular controlled peer to peer (CCP2P) cooperative wireless networks the mobile device is logically connected over cellular links with the base station and simultaneously over short......-range links with neighboring mobile devices to form cooperative clusters. So far the physical communication over cellular links and over short-range links are separated in time or in frequency. Beyond this state of the art, we exploit a method, referred to as asymmetrical modulation, where a mobile device...

  10. A Secure Communication Suite for Underwater Acoustic Sensor Networks

    Directory of Open Access Journals (Sweden)

    Angelica Lo Duca

    2012-11-01

    Full Text Available 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.

  11. Knowledge Discovery from Communication Network Alarm Databases

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The technique of Knowledge Discovery in Databases(KDD) to learn valuable knowledge hidden in network alarm databases is introduced. To get such knowledge, we propose an efficient method based on sliding windows (named as Slidwin) to discover different episode rules from time sequential alarm data. The experimental results show that given different thresholds parameters, large amount of different rules could be discovered quickly.

  12. Personal communication in traditional cellular networks

    Science.gov (United States)

    Neuer, Ellwood I.

    1996-01-01

    The purpose of this paper is to describe the flow of calls through the mobile network as it applies to the operation of Basic and Enhanced Services. Included in the discussion is the overall network layout, the physical connections between the network entities, and the signaling protocols which allow the entities to be integrated. The specific functionality of the applications and services are not detailed as the specific implementation varies from vendor to vendor and from service provider to service provider. The Enhanced Services Platform is installed in a service providers network in order to offer mobile subscribers services and applications which would otherwise not be available. The service providers' objective is to increase revenue/subscriber, increase subscriber loyalty/decrease churn, and build competitive advantages through differentiation. The services provided on the Enhanced Services platform can be viewed as either Basic or Enhanced. For the purpose of this paper, Basic Services refers to Numeric Paging, Call Answering, and Voice Messaging while Enhanced Services refers to FAX Messaging, One Number Service, Voice Dialing and other Voice Recognition applications, Information Services including FAX on Demand, and Automated Call Routing.

  13. Distributed Probabilistic Synchronization Algorithms for Communication Networks

    OpenAIRE

    AKAR, MEHMET; Shorten, Robert

    2008-01-01

    In this paper, we present a probabilistic synchronization algorithm whose convergence properties are examined using tools of rowstochastic matrices. The proposed algorithm is particularly well suited for wireless sensor network applications, where connectivity is not guaranteed at all times, and energy efficiency is an important design consideration. The tradeoff between the convergence speed and the energy use is studied.

  14. Analyzing the ENRON Communication Network Using Agent-Based Simulation

    Directory of Open Access Journals (Sweden)

    Shinako Matsuyama

    2008-07-01

    Full Text Available Agent-based modeling, simulation, and network analysis approaches are one of the emergent techniques among soft computing literature. This paper presents an agent-based model for analyzing the characteristics of peer-to-peer human communication networks. We focus on the process of the collapse of Enron Corporation, which is an interesting topic among the business management domain. The Enron email dataset is available for the analysis. Our approach consists of the four steps: First, macro-level characteristics of the Enron email dataset is analyzed from the viewpoints of social network theory: (i the degrees of the communication networks and contents information, and (ii the changes of network structures among the major events. Second, for the micro-level analysis, an agent-based simulator is implemented using the Enron email dataset. Third, both micro- and macro- level characteristics are calculated on the simulator to ground the model to the dataset. Finally, a different artificial society from the Enron email dataset is developed the simulator and we compare its characteristics of communication patterns with the result of the ones in the agent-based simulation with the Enron email dataset. The investigation suggests that the agent-based model is beneficial to uncover the characteristics of implicit communication mechanisms of the firm.

  15. Non-line-of-sight underwater optical wireless communication network.

    Science.gov (United States)

    Arnon, Shlomi; Kedar, Debbie

    2009-03-01

    The growing need for ocean observation systems has stimulated considerable interest within the research community in advancing the enabling technologies of underwater wireless communication and underwater sensor networks. Sensors and ad hoc sensor networks are the emerging tools for performing extensive data-gathering operations on land, and solutions in the subsea setting are being sought. Efficient communication from the sensors and within the network is critical, but the underwater environment is extremely challenging. Addressing the special features of underwater wireless communication in sensor networks, we propose a novel non-line-of-sight network concept in which the link is implemented by means of back-reflection of the propagating optic signal at the ocean-air interface and derive a mathematical model of the channel. Point-to-multipoint links can be achieved in an energy efficient manner and broadcast broadband communications, such as video transmissions, can be executed. We show achievable bit error rates as a function of sensor node separation and demonstrate the feasibility of this concept using state-of-the-art silicon photomultiplier detectors. PMID:19252651

  16. A network communication and recording system for digital seismic observation

    Institute of Scientific and Technical Information of China (English)

    WANG Hong-ti; ZHUANG Can-tao; XUE Bing; LI Jiang; CHEN Yang; ZHU Xiao-yi; LOU Wen-yu; LIU Ming-hui

    2006-01-01

    A network communication and recording system based on China-made ARCA SOC and embedded Linux operating system is introduced in this paper. It supports TCP/IP network communication protocol and mass storage medium. It has strong points of self-monitor, low power consumption, high timing accuracy, high reliability of operation, etc. It can serve up to 20 centers real-time waveform data at the same time. It meets not only the requirements of physical networking observation, but also virtual networking observation based on Intemet in which real-time data transmission is required. Its ability of field recording also meets the requirements of portable seismic observation, strong motion observation and seismic exploration observation, etc.

  17. Algorithm of communication network reliability combining links, nodes and capacity

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    The conception of the normalized reliability index weighted by capacity is introduced, which combing the communication capacity, the reliability probability of exchange nodes and the reliability probability of the transmission links,in order to estimate the reliability performance of communication network comprehensively and objectively. To realize the full algebraic calculation, the key problem should be resolved, which is to find an algorithm to calculate all the routes between nodes of a network. A kind of logic algebraic algorithm of network routes is studied and based on this algorithm,the full algebraic algorithm of normalized reliability index weighted by capacity is studied. For this algorithm, it is easy to design program and the calculation of reliability index is finished, which is the foundation of the comprehensive and objective estimation of comnunication networks. The calculation procedure of the algorithm is introduced through typical ex amples and the results verify the algorithm.

  18. Using Cryptography in Trust Computing for Networked Communications

    Directory of Open Access Journals (Sweden)

    Dang-Quan Nguyen

    2011-11-01

    Full Text Available We highlight some major difficulties encountered by current approaches that try to model trust computing in a realistic networked communications system. We characterize these approaches as top-down since they assume that trust is universal and readily quantifiable. Our main concern with these approaches is that their quest to define a universal trust often ends up with a loose, context-dependent definition of trust value. Based on this shortcoming of the top-down approaches, we propose another consideration of trust for networked communications. Namely, we underline the fact that trust is first and foremost a security constraint that exists in each specific network's security operation (i.e., attack and defense. Hence, its definition depends on the attack and defense being involved. We call this approach bottom-up and discuss the close relationship between trust and cryptography through some examples of networks attack and defense.

  19. An Anonymous Authentication and Communication Protocol for Wireless Mesh Networks

    OpenAIRE

    Sen, Jaydip

    2011-01-01

    Wireless mesh networks (WMNs) have emerged as a key technology for next generation wireless broadband networks showing rapid progress and inspiring numerous compelling applications. A WMN comprises of a set of mesh routers (MRs) and mesh clients (MCs), where MRs are connected to the Internet backbone through the Internet gateways (IGWs). The MCs are wireless devices and communicate among themselves over possibly multi-hop paths with or without the involvement of MRs. User privacy and security...

  20. Distributed fusion estimation for sensor networks with communication constraints

    CERN Document Server

    Zhang, Wen-An; Song, Haiyu; Yu, Li

    2016-01-01

    This book systematically presents energy-efficient robust fusion estimation methods to achieve thorough and comprehensive results in the context of network-based fusion estimation. It summarizes recent findings on fusion estimation with communication constraints; several novel energy-efficient and robust design methods for dealing with energy constraints and network-induced uncertainties are presented, such as delays, packet losses, and asynchronous information... All the results are presented as algorithms, which are convenient for practical applications.

  1. Seamless and secure communications over heterogeneous wireless networks

    CERN Document Server

    Cao, Jiannong

    2014-01-01

    This brief provides an overview of the requirements, challenges, design issues and major techniques for seamless and secure communications over heterogeneous wireless networks. It summarizes and provides detailed insights into the latest research on handoff management, mobility management, fast authentication and security management to support seamless and secure roaming for mobile clients. The reader will also learn about the challenges in developing relevant technologies and providing ubiquitous Internet access over heterogeneous wireless networks. The authors have extensive experience in im

  2. Future large broadband switched satellite communications networks

    Science.gov (United States)

    Staelin, D. H.; Harvey, R. R.

    1979-01-01

    Critical technical, market, and policy issues relevant to future large broadband switched satellite networks are summarized. Our market projections for the period 1980 to 2000 are compared. Clusters of switched satellites, in lieu of large platforms, etc., are shown to have significant advantages. Analysis of an optimum terrestrial network architecture suggests the proper densities of ground stations and that link reliabilities 99.99% may entail less than a 10% cost premium for diversity protection at 20/30 GHz. These analyses suggest that system costs increase as the 0.6 power of traffic. Cost estimates for nominal 20/30 GHz satellite and ground facilities suggest optimum system configurations might employ satellites with 285 beams, multiple TDMA bands each carrying 256 Mbps, and 16 ft ground station antennas. A nominal development program is outlined.

  3. Max-Flow Min-Cut Theorems for Multi-User Communication Networks

    OpenAIRE

    Riis, Soren; Gadouleau, Maximilien

    2010-01-01

    The paper presents four distinct new ideas and results for communication networks: 1) We show that relay-networks (i.e. communication networks where different nodes use the same coding functions) can be used to model dynamic networks. 2) We introduce {\\em the term model}, which is a simple, graph-free symbolic approach to communication networks. 3) We state and prove variants of a theorem concerning the dispersion of information in single-receiver communications. 4) We show that the solvabili...

  4. The projects of Disaster-Resistant Information Communication Network at the Research Organization of Electrical Communication, Tohoku University

    Science.gov (United States)

    Iwatsuki, Katsumi

    2012-12-01

    After the East Japan Great Earthquake, Tohoku University has established Research Organization of Electrical Communication to achieve the most advanced disaster-resistant information communication network in the world. In this paper, we will introduce our projects of "Disaster-Resistant Information Communication Network" based on industry-academia-government collaboration.

  5. Robust control of integrated motor-transmission powertrain system over controller area network for automotive applications

    Science.gov (United States)

    Zhu, Xiaoyuan; Zhang, Hui; Cao, Dongpu; Fang, Zongde

    2015-06-01

    Integrated motor-transmission (IMT) powertrain system with directly coupled motor and gearbox is a good choice for electric commercial vehicles (e.g., pure electric buses) due to its potential in motor size reduction and energy efficiency improvement. However, the controller design for powertrain oscillation damping becomes challenging due to the elimination of damping components. On the other hand, as controller area network (CAN) is commonly adopted in modern vehicle system, the network-induced time-varying delays that caused by bandwidth limitation will further lead to powertrain vibration or even destabilize the powertrain control system. Therefore, in this paper, a robust energy-to-peak controller is proposed for the IMT powertrain system to address the oscillation damping problem and also attenuate the external disturbance. The control law adopted here is based on a multivariable PI control, which ensures the applicability and performance of the proposed controller in engineering practice. With the linearized delay uncertainties characterized by polytopic inclusions, a delay-free closed-loop augmented system is established for the IMT powertrain system under discrete-time framework. The proposed controller design problem is then converted to a static output feedback (SOF) controller design problem where the feedback control gains are obtained by solving a set of linear matrix inequalities (LMIs). The effectiveness as well as robustness of the proposed controller is demonstrated by comparing its performance against that of a conventional PI controller.

  6. Systems thinking in designing automotive textiles

    OpenAIRE

    Sinha, Pammi; Muthu, Subramanian Senthilkannan; Taylor, Iain; Schulz, Rita; Beverley, Katharine J.; Day, Claire L.; Tipi, Nicoleta S.

    2015-01-01

    We present the complexities in terms of designing automotive exterior seating materials (seat coverings and interior linings) at Sage Automotive Interiors (UK), which is a division of a global international automotive textile supplier with headquarters in the US. Sustainability and innovation are emphasized in documents communicating the company’s vision. Using a case study approach, we consider the current design, development and manufacture process and examine it for the potential for feedb...

  7. Applying Model Based Systems Engineering to NASA's Space Communications Networks

    Science.gov (United States)

    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

  8. NFMIC Cooperative Communication Methods for Body Area Networks

    Directory of Open Access Journals (Sweden)

    Mehrnoush Masihpour

    2012-09-01

    Full Text Available To achieve higher data rate or to extend the coverage range of a wireless communication system, cooperative relay has been seen as a promising solution. This concept has been integrated in many traditional wireless communication networks. However, it has not been extensively examined for near field magnetic induction communication (NFMIC systems. This paper aims to apply cooperative relay to NFMIC in a sense that is applicable to body area networking, since NFMIC is stated to be a suitable physical layer for body area networks. We have shown that using idle NFMIC nodes as relaying terminals, the system performance will be enhanced, as compared to a point to point communication system. In this context we have proposed three relaying methods to enhance the data rate and the received signal power in a personal area network. The relaying strategies are denoted as MI-Relay, MAMI Relay1 and MAMI Relay2. In this paper, using theoretical studies and simulation results, we have compared the performance of the three strategies and we have shown that higher data rates can be achieved through MAMI Relay1. However, we have discussed that the separation distance between relaying nodes and the source or destination can be a key factor for relay node selection.

  9. Indian-Spanish Communication Networks: Continuity in the Greater Southwest.

    Science.gov (United States)

    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…

  10. Knowledge work and communication challenges in networked enterprises

    NARCIS (Netherlands)

    Barjis, J.; Gupta, A.; Sharda, R.

    2010-01-01

    A modern enterprise is a heavily wired and networked socio-technical system where multiple components play in symphony to yield a competitive position in the ear of digital economy. While the underling communication and interaction systems facilitate knowledge workers to carry out the enterprise mis

  11. Localization and Communication for UWB-based Wireless Sensor Networks

    NARCIS (Netherlands)

    Wang, Y.

    2011-01-01

    The great demand for location-aware wireless sensor networks (WSNs) motivates the research in this thesis. The unique characteristics of WSNs impose numerous challenges on localization and communication. In this thesis, we handle some key challenges and provide affordable solutions. Impulse radio u

  12. Role of Communication Networks in Behavioral Systems Analysis

    Science.gov (United States)

    Houmanfar, Ramona; Rodrigues, Nischal Joseph; Smith, Gregory S.

    2009-01-01

    This article provides an overview of communication networks and the role of verbal behavior in behavioral systems analysis. Our discussion highlights styles of leadership in the design and implementation of effective organizational contingencies that affect ways by which coordinated work practices are managed. We draw upon literature pertaining to…

  13. Gender, Information and Communication Networks: Implications for Extension.

    Science.gov (United States)

    Subedi, A.; Garforth, Chr.

    1996-01-01

    In Nepal a study of 243 female and 179 male farmers showed that males demonstrated horizontal communication patterns among themselves; females actively sought information in both horizontal and heterogeneous patterns. Extension strategies that take advantage of gender-based networks were suggested to increase the flow of information. (SK)

  14. Results of computer network experiment via the Japanese communication satellite CS - Performance evaluation of communication protocols

    Science.gov (United States)

    Ito, A.; Kakinuma, Y.; Uchida, K.; Matsumoto, K.; Takahashi, H.

    1984-03-01

    Computer network experiments have been performed by using the Japanese communication satellite CS. The network is of a centralized (star) type, consisting of one center station and many user stations. The protocols are determined taking into consideration the long round trip delay of a satellite channel. This paper treats the communication protocol aspects of the experiments. Performances of the burst level and the link protocols (which correspond nearly to data link layer of OSI 7 layer model) are evaluated. System performances of throughput, delay, link level overhead are measured by using the statistically generated traffic.

  15. Fast quantum communication in linear networks

    Science.gov (United States)

    Jacobs, Kurt; Wu, Rebing; Wang, Xiaoting; Ashhab, Sahel; Chen, Qi-Ming; Rabitz, Herschel

    2016-05-01

    Here we consider the speed at which quantum information can be transferred between the nodes of a linear network. Because such nodes are linear oscillators, this speed is also important in the cooling and state preparation of mechanical oscillators, as well as in frequency conversion. We show that if there is no restriction on the size of the linear coupling between two oscillators, then there exist control protocols that will swap their respective states with high fidelity within a time much shorter than a single oscillation period. Standard gradient search methods fail to find these fast protocols. We were able to do so by augmenting standard search methods with a path-tracing technique, demonstrating that this technique has remarkable power to solve time-optimal control problems, as well as confirming the highly challenging nature of these problems. As a further demonstration of the power of path tracing, first introduced by Moore Tibbets et al. (Phys. Rev. A, 86 (2012) 062309), we apply it to the generation of entanglement in a linear network.

  16. The Study on the Communication Network of Wide Area Measurement System in Electricity Grid

    Science.gov (United States)

    Xiaorong, Cheng; Ying, Wang; Yangdan, Ni

    Wide area measurement system(WAMS) is a fundamental part of security defense in Smart Grid, and the communication system of WAMS is an important part of Electric power communication network. For a large regional network is concerned, the real-time data which is transferred in the communication network of WAMS will affect the safe operation of the power grid directly. Therefore, WAMS raised higher requirements for real-time, reliability and security to its communication network. In this paper, the architecture of WASM communication network was studied according to the seven layers model of the open systems interconnection(OSI), and the network architecture was researched from all levels. We explored the media of WAMS communication network, the network communication protocol and network technology. Finally, the delay of the network were analyzed.

  17. 75 FR 26180 - Effects on Broadband Communications Networks of Damage To or Failure of Network Equipment or...

    Science.gov (United States)

    2010-05-11

    ... telephone network (PSTN), but communicate through a wide range of interconnected networks (e.g., cable... telephone network (PSTN), for example, switches, routers, and multiplexers often protect against service... COMMISSION 47 CFR Chapter I Effects on Broadband Communications Networks of Damage To or Failure of...

  18. Influence and Dissemination Of Sentiments in Social Network Communication Patterns

    DEFF Research Database (Denmark)

    Hillmann, Robert; Trier, Matthias

    2013-01-01

    in online environments. We develop a theoretical framework that tries to bridge the gap between social influence theories that focus on offline interactions on one hand and online interaction in social networks on the other hand. We then test our hypothesis about the influence and dissemination......Previous research suggests the existence of sentiments in online social networks. In comparison to real life human interaction, in which sentiments have been shown to have an influence on human behaviour, it is not yet completely understood which mechanisms explain how sentiments influence users...... of sentiments in a quantitative analysis that is based on retrieved textual messages of communication patterns in over 12000 online social networks. Our empirical results suggest a general influence of sentiments on node communication patterns that is evidenced by increased occurrences of subsequent messages...

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

    Science.gov (United States)

    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.

  20. Adjacency Matrix based method to compute the node connectivity of a Computer Communication Network

    CERN Document Server

    Kamalesh, V N

    2010-01-01

    Survivability of a computer communication network is the ability of a network to provide continuous service in the presence of link or node failures. It is an essential and considerable concern in the design of high speed communication network topologies. The connectivity number of a network is the graph theoretical metric to measure survivability of the communication network. Given a network and a positive integer k, few heuristics exist in literature to verify whether the given network is k connected or not. This paper presents a method to compute the connectivity number k of a given computer communication network.

  1. Communications, Navigation, and Network Reconfigurable Test-bed Flight Hardware Compatibility Test S

    Science.gov (United States)

    2010-01-01

    Communications, Navigation, and Network Reconfigurable Test-bed Flight Hardware Compatibility Test Sets and Networks Integration Management Office Testing for the Tracking and Data Relay Satellite System

  2. Operational Concepts for a Generic Space Exploration Communication Network Architecture

    Science.gov (United States)

    Ivancic, William D.; Vaden, Karl R.; Jones, Robert E.; Roberts, Anthony M.

    2015-01-01

    This document is one of three. It describes the Operational Concept (OpsCon) for a generic space exploration communication architecture. The purpose of this particular document is to identify communication flows and data types. Two other documents accompany this document, a security policy profile and a communication architecture document. The operational concepts should be read first followed by the security policy profile and then the architecture document. The overall goal is to design a generic space exploration communication network architecture that is affordable, deployable, maintainable, securable, evolvable, reliable, and adaptable. The architecture should also require limited reconfiguration throughout system development and deployment. System deployment includes: subsystem development in a factory setting, system integration in a laboratory setting, launch preparation, launch, and deployment and operation in space.

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

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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.

  5. Network Communication as a Service-Oriented Capability

    Energy Technology Data Exchange (ETDEWEB)

    Johnston, William; Johnston, William; Metzger, Joe; Collins, Michael; Burrescia, Joseph; Dart, Eli; Gagliardi, Jim; Guok, Chin; Oberman, Kevin; O' Conner, Mike

    2008-01-08

    In widely distributed systems generally, and in science-oriented Grids in particular, software, CPU time, storage, etc., are treated as"services" -- they can be allocated and used with service guarantees that allows them to be integrated into systems that perform complex tasks. Network communication is currently not a service -- it is provided, in general, as a"best effort" capability with no guarantees and only statistical predictability. In order for Grids (and most types of systems with widely distributed components) to be successful in performing the sustained, complex tasks of large-scale science -- e.g., the multi-disciplinary simulation of next generation climate modeling and management and analysis of the petabytes of data that will come from the next generation of scientific instrument (which is very soon for the LHC at CERN) -- networks must provide communication capability that is service-oriented: That is it must be configurable, schedulable, predictable, and reliable. In order to accomplish this, the research and education network community is undertaking a strategy that involves changes in network architecture to support multiple classes of service; development and deployment of service-oriented communication services, and; monitoring and reporting in a form that is directly useful to the application-oriented system so that it may adapt to communications failures. In this paper we describe ESnet's approach to each of these -- an approach that is part of an international community effort to have intra-distributed system communication be based on a service-oriented capability.

  6. Distributed wireless quantum communication networks with partially entangled pairs

    International Nuclear Information System (INIS)

    Wireless quantum communication networks transfer quantum state by teleportation. Existing research focuses on maximal entangled pairs. In this paper, we analyse the distributed wireless quantum communication networks with partially entangled pairs. A quantum routing scheme with multi-hop teleportation is proposed. With the proposed scheme, is not necessary for the quantum path to be consistent with the classical path. The quantum path and its associated classical path are established in a distributed way. Direct multi-hop teleportation is conducted on the selected path to transfer a quantum state from the source to the destination. Based on the feature of multi-hop teleportation using partially entangled pairs, if the node number of the quantum path is even, the destination node will add another teleportation at itself. We simulated the performance of distributed wireless quantum communication networks with a partially entangled state. The probability of transferring the quantum state successfully is statistically analyzed. Our work shows that multi-hop teleportation on distributed wireless quantum networks with partially entangled pairs is feasible. (general)

  7. Can communications and sensors work together in one network?

    Institute of Scientific and Technical Information of China (English)

    Xinwan LI; Jianping CHEN

    2009-01-01

    With the development of both optical fiber-based communication and sensation, one interesting topic has been pointed out. How to connect those mountains of sensors to detect the signal in a large area, and how to make the cost of sensing system lower enough should be studied. A network of sensors is a good option. All sensing equipments, including the interrogators and the sensors, will be internetworking together. However, fiber optic communication networks have been developed very well over the past two decades. Is it necessary to rebuild a new network for sensors? In this paper, some new technologies in the two areas of fiber optic sensors and fiber optic communication will be addressed. Then, the available overlay architecture of a fiber optic sensors network will be presented. Finally, a polymorphous optical burst switching (POBS)-based architecture will be proposed, which can support all kinds of services, including digital data optical circuit/burst/packet switching and analog fiber optic sensor signal circuit/burst switching, etc.

  8. Establishing communication networks for health promotion in industrial settings.

    Science.gov (United States)

    Heirich, M A; Cameron, V; Erfurt, J C; Foote, A; Gregg, W

    1989-11-01

    Abstract Health educators, medical personnel, and managers interested in worksite efforts to change health behaviors often face problems in communicating effectively with rank and file members of the workforce. This article describes an effective strategy for getting health information flowing among an industrial workforce and changing health behaviors. Identifying effective communication routes at a worksite and creating new ones, establishing relationships with key information carriers, and making health information salient to potential communicators are keys to successful information flow. Wellness Committees can provide access to formal communication routes, which may or may not work for health information. One-to-one counseling and development of buddy systems, however, create short-link, health-oriented communication networks. If people whom large numbers of employees contact for plant business get recruited into these health networks, information spreads rapidly. Poster posting can generate interaction with people so that they read and talk about health messages. Unusual motion, sound, and messages can call attention to special events. Using these methods has increased participation in specific health activities from a handful to between fifty and one hundred people at a time. PMID:22204404

  9. A supervisory control policy over an acoustic communication network

    Science.gov (United States)

    Farhadi, Alireza; Dumon, Jonathan; Canudas-de-Wit, Carlos

    2015-05-01

    This paper presents a supervisory multi-agent control policy over an acoustic communication network subject to imperfections (packet dropout and transmission delay) for localisation of an underwater flow source (e.g., source of chemical pollution, fresh water, etc.) with an unknown location at the bottom of the ocean. A two-loop control policy combined with a coding strategy for reliable communication is presented to perform the above task. A simulator is developed and used to evaluate the trade-offs between quality of communication, transmission delay and control for a fleet of autonomous underwater vehicles supervised over a noisy acoustic communication network by an autonomous surface vessel. It is illustrated that without compensation of the effects of severe random packet dropout, localisation of an unknown underwater flow source is not possible for the condition simulated just by implementing a two-loop control policy. But a two-loop control policy combined with a strategy for reliable communication locates the unknown location of flow source.

  10. Ultra-Reliable Communications in Failure-Prone Realistic Networks

    DEFF Research Database (Denmark)

    Gerardino, Guillermo Andrés Pocovi; Lauridsen, Mads; Alvarez, Beatriz Soret;

    2016-01-01

    We investigate the potential of different diversity and interference management techniques to achieve the required downlink SINR outage probability for ultra-reliable communications. The evaluation is performed in a realistic network deployment based on site-specific data from a European capital....... Micro and macroscopic diversity techniques are proved to be important enablers of ultra-reliable communications. Particularly, it is shown how a 4x4 MIMO scheme with three orders of macroscopic diversity can achieve the required SINR outage performance. Smaller gains are obtained from interference...

  11. Secure and Authenticated Data Communication in Wireless Sensor Networks.

    Science.gov (United States)

    Alfandi, Omar; Bochem, Arne; Kellner, Ansgar; Göge, Christian; Hogrefe, Dieter

    2015-01-01

    Securing communications in wireless sensor networks is increasingly important as the diversity of applications increases. However, even today, it is equally important for the measures employed to be energy efficient. For this reason, this publication analyzes the suitability of various cryptographic primitives for use in WSNs according to various criteria and, finally, describes a modular, PKI-based framework for confidential, authenticated, secure communications in which most suitable primitives can be employed. Due to the limited capabilities of common WSN motes, criteria for the selection of primitives are security, power efficiency and memory requirements. The implementation of the framework and the singular components have been tested and benchmarked in our testbed of IRISmotes.

  12. Study on Communication Mode of Wireless Sensor Networks Based on Effective Result

    International Nuclear Information System (INIS)

    The key challenge in wireless sensor networks is maximizing network lifetime. It will significantly reduce energy consumption of communication and prolong networks lifetime to choose appropriate communication mode. In this paper, energy model and communication topology are proposed, and then from the viewpoint of effective result, expression for communication energy cost of single sensor node and overall system in different communication mode is derived, impact that sensor nodes amount, communication radius and propagation loss exponent pose on communication mode based on simulations is analyzed, and the justification for choosing communication mode is summarized

  13. A Quantitative Analysis on Network Communication Research Papers in China from 1995 to 2006

    OpenAIRE

    Chengliang Zhang

    2009-01-01

    In recent years, the research on network communication becomes popular gradually along with the upsurge of new media, and turns into a new focus in new communication field. By studying network communication papers from 1995 to 2006, this paper makes a relatively objective quantitative analysis of network communication’s present researches and latest explorations in China.

  14. Balancing Ties: Boundary Spanning and Influence in the Organization's Extended Network of Communication.

    Science.gov (United States)

    Manev, Ivan M.; Stevenson, William B.

    2001-01-01

    Presents a study of the business communication connecting an organization with others in its environment. Links boundary spanning with network theory and proposes the concept of an extended network of communication. Studies the relationship between boundary-spanning communication and individual influence in a network with 108 organizational…

  15. High-Throughput Network Communication with NetIO

    CERN Document Server

    Schumacher, J\\"orn; The ATLAS collaboration

    2016-01-01

    HPC network technologies like Infiniband, TrueScale or OmniPath provide low-latency and high-throughput communication between hosts, which makes them attractive options for data-acquisition systems in large-scale high-energy physics experiments. Like HPC networks, DAQ networks are local and include a well specified number of systems. Unfortunately traditional network communication APIs for HPC clusters like MPI or PGAS target exclusively the HPC community and are not suited well for DAQ applications. It is possible to build distributed DAQ applications using low-level system APIs like Infiniband Verbs (and this has been done), but it requires a non negligible effort and expert knowledge. On the other hand, message services like 0MQ have gained popularity in the HEP community. Such APIs allow to build distributed applications with a high-level approach and provide good performance. Unfortunately their usage usually limits developers to TCP/IP-based networks. While it is possible to operate a TCP/IP stack on to...

  16. ECS: Efficient Communication Scheduling for Underwater Sensor Networks

    Directory of Open Access Journals (Sweden)

    Lu Hong

    2011-03-01

    Full Text Available TDMA protocols have attracted a lot of attention for underwater acoustic sensor networks (UWSNs, because of the unique characteristics of acoustic signal propagation such as great energy consumption in transmission, long propagation delay and long communication range. Previous TDMA protocols all allocated transmission time to nodes based on discrete time slots. This paper proposes an efficient continuous time scheduling TDMA protocol (ECS for UWSNs, including the continuous time based and sender oriented conflict analysis model, the transmission moment allocation algorithm and the distributed topology maintenance algorithm. Simulation results confirm that ECS improves network throughput by 20% on average, compared to existing MAC protocols.

  17. Adaptive swarm-based routing in communication networks

    Institute of Scientific and Technical Information of China (English)

    吕勇; 赵光宙; 苏凡军; 历小润

    2004-01-01

    Swarm intelligence inspired by the social behavior of ants boasts a number of attractive features,including adaptation,robustness and distributed,decentralized nature,which are well suited for routing in modern communication networks.This paper describes an adaptive swarm-based routing algorithm that increases convergence speed,reduces routing instabilities and oscillations by using a novel variation of reinforcement learning and a technique called momentum.Experiment on the dynamic network showed that adaptive swarm-based routing learns the optimum routing in terms of convergence speed and average packet latency.

  18. Adaptive swarm-based routing in communication networks

    Institute of Scientific and Technical Information of China (English)

    吕勇; 赵光宙; 苏凡军; 历小润

    2004-01-01

    Swarm intelligence inspired by the social behavior of ants boasts a number of attractive features, including adaptation, robustness and distributed, decentralized nature, which are well suited for routing in modern communication networks. This paper describes an adaptive swarm-based routing algorithm that increases convergence speed, reduces routing instabilities and oscillations by using a novel variation of reinforcement learning and a technique called momentum.Experiment on the dynamic network showed that adaptive swarm-based routing learns the optimum routing in terms of convergence speed and average packet latency.

  19. Radio propagation and adaptive antennas for wireless communication networks

    CERN Document Server

    Blaunstein, Nathan

    2014-01-01

    Explores novel wireless networks beyond 3G, and advanced 4G technologies, such as MIMO, via propagation phenomena and the fundamentals of adapted antenna usage.Explains how adaptive antennas can improve GoS and QoS for any wireless channel, with specific examples and applications in land, aircraft and satellite communications.Introduces new stochastic approach based on several multi-parametric models describing various terrestrial scenarios, which have been experimentally verified in different environmental conditionsNew chapters on fundamentals of wireless networks, cellular and non-cellular,

  20. ECS: efficient communication scheduling for underwater sensor networks.

    Science.gov (United States)

    Hong, Lu; Hong, Feng; Guo, Zhongwen; Li, Zhengbao

    2011-01-01

    TDMA protocols have attracted a lot of attention for underwater acoustic sensor networks (UWSNs), because of the unique characteristics of acoustic signal propagation such as great energy consumption in transmission, long propagation delay and long communication range. Previous TDMA protocols all allocated transmission time to nodes based on discrete time slots. This paper proposes an efficient continuous time scheduling TDMA protocol (ECS) for UWSNs, including the continuous time based and sender oriented conflict analysis model, the transmission moment allocation algorithm and the distributed topology maintenance algorithm. Simulation results confirm that ECS improves network throughput by 20% on average, compared to existing MAC protocols.

  1. Stochastic network optimization with application to communication and queueing systems

    CERN Document Server

    Neely, Michael

    2010-01-01

    This text presents a modern theory of analysis, control, and optimization for dynamic networks. Mathematical techniques of Lyapunov drift and Lyapunov optimization are developed and shown to enable constrained optimization of time averages in general stochastic systems. The focus is on communication and queueing systems, including wireless networks with time-varying channels, mobility, and randomly arriving traffic. A simple drift-plus-penalty framework is used to optimize time averages such as throughput, throughput-utility, power, and distortion. Explicit performance-delay tradeoffs are prov

  2. Practical issues in picture archiving and communication system and networking

    International Nuclear Information System (INIS)

    Picture Archiving and Communication System (PACS) is a key workflow tool in the functioning of radiology departments worldwide, today, and its utilization is rapidly growing in India. The key challenges in PACS implementation are related to vendor and feature selection, integration with the existing HIS, user training, maintenance and scalability to meet increasing demands. Additionally, the networking requirements that PACS imposes on hospital networks are not insignificant. This article attempts to review these issues from the standpoint of what a prospective or new user needs to know

  3. Successive lag synchronization on dynamical networks with communication delay

    Science.gov (United States)

    Xin-Jian, Zhang; Ai-Ju, Wei; Ke-Zan, Li

    2016-03-01

    In this paper, successive lag synchronization (SLS) on a dynamical network with communication delay is investigated. In order to achieve SLS on the dynamical network with communication delay, we design linear feedback control and adaptive control, respectively. By using the Lyapunov function method, we obtain some sufficient conditions for global stability of SLS. To verify these results, some numerical examples are further presented. This work may find potential applications in consensus of multi-agent systems. Project supported by the National Natural Science Foundation of China (Grant No. 61004101), the Natural Science Foundation Program of Guangxi Province, China (Grant No. 2015GXNSFBB139002), the Graduate Innovation Project of Guilin University of Electronic Technology, China (Grant No. GDYCSZ201472), and the Guangxi Colleges and Universities Key Laboratory of Data Analysis and Computation, Guilin University of Electronic Technology, China.

  4. Interpreting network communicability with stochastic models and data

    CERN Document Server

    Colman, Ewan

    2016-01-01

    The recently introduced concept of dynamic communicability is a valuable tool for ranking the importance of nodes in a temporal network. Two metrics, broadcast score and receive score, were introduced to measure the centrality of a node with respect to a model of contagion based on time-respecting walks. This article examines the temporal and structural factors influencing these metrics by considering a versatile stochastic temporal network model. We analytically derive formulae to accurately predict the expectation of the broadcast and receive scores when one or more columns in a temporal edge-list are shuffled. These methods are then applied to two publicly available data-sets and we quantify how much the centrality of each individual depends on structural or temporal influences. From our analysis we highlight two practical contributions: a way to control for temporal variation when computing dynamic communicability, and the conclusion that the broadcast and receive scores can, under a range of circumstance...

  5. Gossip-based Search in Multipeer Communication Networks

    CERN Document Server

    Jaho, Eva; Tang, Siyu; Stavrakakis, Ioannis; Van Mieghem, Piet

    2009-01-01

    We study a gossip-based algorithm for searching data objects in a multipeer communication network. All of the nodes in the network are able to communicate with each other. There exists an initiator node that starts a round of searches by randomly querying one or more of its neighbors for a desired object. The queried nodes can also be activated and look for the object. We examine several behavioural patterns of nodes with respect to their willingness to cooperate in the search. We derive mathematical models for the search process based on the balls and bins model, as well as known approximations for the rumour-spreading problem. All models are validated with simulations. We also evaluate the performance of the algorithm and examine the impact of search parameters.

  6. Asymmetries in commitment in an avian communication network

    Science.gov (United States)

    Randler, Christoph; Vollmer, Christian

    2013-02-01

    Mobbing of predators occurs within a conspecific and heterospecific context but has not been quantified within the framework of a communication network and analysed with respect to heterospecific reciprocity. Here, we used playbacks of mobbing calls to show that mobbing is unequally distributed within a community of deciduous forest birds. Five species (great tit Parus major, blue tit Cyanistes caeruleus, marsh tit Poecile palustris, nuthatch Sitta europaea and chaffinch Fringilla coelebs) responded to each other's playbacks of mobbing calls. Commitment to mob was measured by minimum distance, response latency and uttering of calls. Commitment was higher when conspecific calls were broadcast. Yet, responses to heterospecific calls were significantly different between the five species. Chaffinches had the lowest commitment, and blue tits tended to have the highest. The communication network is asymmetric. Some species invest more than they receive from other species. As mobbing might incur costs, these are unequally distributed across the community.

  7. Analyzing the Dynamics of Communication in Online Social Networks

    Science.gov (United States)

    de Choudhury, Munmun; Sundaram, Hari; John, Ajita; Seligmann, Doree Duncan

    This chapter deals with the analysis of interpersonal communication dynamics in online social networks and social media. Communication is central to the evolution of social systems. Today, the different online social sites feature variegated interactional affordances, ranging from blogging, micro-blogging, sharing media elements (i.e., image, video) as well as a rich set of social actions such as tagging, voting, commenting and so on. Consequently, these communication tools have begun to redefine the ways in which we exchange information or concepts, and how the media channels impact our online interactional behavior. Our central hypothesis is that such communication dynamics between individuals manifest themselves via two key aspects: the information or concept that is the content of communication, and the channel i.e., the media via which communication takes place. We present computational models and discuss large-scale quantitative observational studies for both these organizing ideas. First, we develop a computational framework to determine the "interestingness" property of conversations cented around rich media. Second, we present user models of diffusion of social actions and study the impact of homophily on the diffusion process. The outcome of this research is twofold. First, extensive empirical studies on datasets from YouTube have indicated that on rich media sites, the conversations that are deemed "interesting" appear to have consequential impact on the properties of the social network they are associated with: in terms of degree of participation of the individuals in future conversations, thematic diffusion as well as emergent cohesiveness in activity among the concerned participants in the network. Second, observational and computational studies on large social media datasets such as Twitter have indicated that diffusion of social actions in a network can be indicative of future information cascades. Besides, given a topic, these cascades are often a

  8. A PERFORMANCE EVALUATION INDEX SYSTEM FOR MULTIMEDIA COMMUNICATION NETWORKS AND FORECASTING FOR WEB-BASED NETWORK TRAFFIC

    Institute of Scientific and Technical Information of China (English)

    Wuyi YUE; Jifa GU; Xijin TANG

    2004-01-01

    This paper presents a new index system for the performance evaluation and network planning of multimedia communication systems using measurement on actual systems to support several different traffic types. In this index system, we develop an expert system to evaluate the performance of such multimedia communication networks including channel utilization and call blocking probability andpacket delay, and apply the network planning methods to optimize the networks and forecast thedemand of the growing multimedia communications systems. Two important planning problems for the multimedia communication systems are presented: optimization problem for construction of the world system and forecast problem for increasing traffic demands. We first discuss analysis methods,performance measures for the multimedia communication systems. Then, we describe network planning methods for the multimedia communication systems and give some efficiency network planning methods. Finally, we present some results studied in traffic forecast for the campus network and show the effectiveness of these methods.

  9. Role of information and communication networks in malaria survival

    Directory of Open Access Journals (Sweden)

    Marathe Achla

    2007-10-01

    Full Text Available Abstract Background Quite often symptoms of malaria go unrecognized or untreated. According to the Multilateral Initiative on Malaria, 70% of the malaria cases that are treated at home are mismanaged. Up to 82% of all malaria episodes in sub-Saharan Africa are treated outside the formal health sector. Fast and appropriate diagnosis and treatment of malaria is extremely important in reducing morbidity and mortality. Method Data from 70 different countries is pooled together to construct a panel dataset of health and socio-economic variables for a time span of (1960–2004. The generalized two-stage least squares and panel data models are used to investigate the impact of information and communication network (ICN variables on malaria death probability. The intensity of ICN is represented by the number of telephone main lines per 1,000 people and the number of television sets per 1,000 people. Results The major finding is that the intensity of ICN is associated with reduced probability of deaths of people that are clinically identified as malaria infected. The results are robust for both indicators i.e. interpersonal and mass communication networks and for all model specifications examined. Conclusion The results suggest that information and communication networks can substantially scale up the effectiveness of the existing resources for malaria prevention. Resources spent in preventing malaria are far less than needed. Expanded information and communication networks will widen the avenues for community based "participatory development", that encourages the use of local information, knowledge and decision making. Timely information, immediate care and collective knowledge based treatment can be extremely important in reducing child mortality and achieving the millennium development goal.

  10. Optimization of bandwidth of communication channels of corporate networks

    Directory of Open Access Journals (Sweden)

    G. I. Bondarenko

    2014-09-01

    Full Text Available Introduction. This article contains overview of the organization of communication between applications on the corporate network. It is stated that the main digital channel (channel B - 64 kbit/s and the primary digital channel (channel E1 the digital stream - 2048 kbit/s are used as the main channels in corporate networks. Problem areas of the functioning of the corporate network are identified. There are the rent of communication channels, which is growing rapidly with increasing the quality and speed of data transmission, and optimal use of bandwidth of communication channels. Setting of task. Optimal use of transmission channels bandwidth and minimizing the rent cost of channels is possible in two ways - the use of compression techniques of voice and video information and the application of variable structure of channels by using various-speed transmission channels. Differential pulse code modulation, adaptive differential pulse code modulation are the modern methods of speech signals processing. Organization of various-speed channels is performed in the structure of the BCC (for speech signals or PCR (for video. Suggestions for optimizing the structure of the channel signals. Proposed method of various-speed channels formation by using the channel intervals appropriate BCC (octets in the structure of signals E1 as envelopes containing various-speed channels. Channels can be selected for synchronization procedure CRC to simplify recognition of channels in the structure of E1. In this case, the minimal speed in the channel is 4 kbit/s. Conclusions. The proposed structure of envelopes is based on octet channel intervals of standard group signal of the primary group plesiochronous hierarchy E1 when transferring various-speed digital signals maximum allows to use the bandwidth at a fixed structure of channel interval, it makes possible to agree on the structure of the various-speed signals with the existing in communication networks.

  11. An Efficient Secure Multicast Communication for P2P Network

    Directory of Open Access Journals (Sweden)

    Huaiqing Lin

    2011-03-01

    Full Text Available A new algorithm for efficient key management for secure group communication in P2P network is presented. The protocol avoids the escrow problem in identity-based cryptosystem and the secure delivery of private keys. It has two rounds and requires constant pairing operation per user. The security of protocol is based on some underlying problems closely related to the Bilinear Diffie-Hellman Problem are computationally hard.  

  12. A Secure Communication Suite for Underwater Acoustic Sensor Networks

    OpenAIRE

    Angelica Lo Duca; Gianluca Dini

    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 f...

  13. An Overview on Wavelets in Source Coding, Communications, and Networks

    Directory of Open Access Journals (Sweden)

    Pesquet-Popescu Béatrice

    2007-01-01

    Full Text Available The use of wavelets in the broad areas of source coding, communications, and networks is surveyed. Specifically, the impact of wavelets and wavelet theory in image coding, video coding, image interpolation, image-adaptive lifting transforms, multiple-description coding, and joint source-channel coding is overviewed. Recent contributions in these areas arising in subsequent papers of the present special issue are described.

  14. An Overview on Wavelets in Source Coding, Communications, and Networks

    Directory of Open Access Journals (Sweden)

    James E. Fowler

    2007-06-01

    Full Text Available The use of wavelets in the broad areas of source coding, communications, and networks is surveyed. Specifically, the impact of wavelets and wavelet theory in image coding, video coding, image interpolation, image-adaptive lifting transforms, multiple-description coding, and joint source-channel coding is overviewed. Recent contributions in these areas arising in subsequent papers of the present special issue are described.

  15. Low-Complex Reliable Communications between Wireless Network-Nodes

    Directory of Open Access Journals (Sweden)

    Alois Goiser

    2015-11-01

    Full Text Available We present a low-complex blind interference reduction scheme embedded in the receiver to enhance correlative data detection. The key element is a statistically controlled adaptive nonlinearity prior to correlation. This add-on feature guaranties reliable communication between network-nodes in any type of noise and/or interference. Additionally the concept provides accurate position measurements to make services flexible and intelligent.

  16. 75 FR 49870 - Effects on Broadband Communications Networks of Damage to or Failure of Network Equipment or...

    Science.gov (United States)

    2010-08-16

    ... From the Federal Register Online via the Government Publishing Office FEDERAL COMMUNICATIONS COMMISSION 47 CFR Chapter I Effects on Broadband Communications Networks of Damage to or Failure of Network Equipment or Severe Overload AGENCY: Federal Communications Commission ACTION: Proposed rule; extension...

  17. Organizational structure and communication networks in a university environment

    CERN Document Server

    Mathiesen, Joachim; Sneppen, Kim

    2010-01-01

    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 e-mail 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 e-mails messages within modules scales with module size to the power of $1.29\\pm .06$, and the frequency of communication between individuals decays exponentially with the number of links required upwards in the organizational hierarchy before they are connected. Our data also indicates that the number of messages sent by administrative units is proportional...

  18. A programmable analog VLSI neural network processor for communication receivers.

    Science.gov (United States)

    Choi, J; Bang, S H; Sheu, B J

    1993-01-01

    An analog VLSI neural network processor was designed and fabricated for communication receiver applications. It does not require prior estimation of the channel characteristics. A powerful channel equalizer was implemented with this processor chip configured as a four-layered perceptron network. The compact synapse cell is realized with an enhanced wide-range Gilbert multiplier circuit. The output neuron consists of a linear current-to-voltage converter and a sigmoid function generator with a controllable voltage gain. Network training is performed by the modified Kalman neuro-filtering algorithm to speed up the convergence process for intersymbol interference and white Gaussian noise communication channels. The learning process is done in the companion DSP board which also keeps the synapse weight for later use of the chip. The VLSI neural network processor chip occupies a silicon area of 4.6 mmx6.8 mm and was fabricated in a 2-mum double-polysilicon CMOS technology. System analysis and experimental results are presented. PMID:18267752

  19. The communications in early warning network for radiation monitoring

    International Nuclear Information System (INIS)

    The objectives of early warning network are: The determination of gamma radiation (background) levels in air which depend on location and time, evaluation of any situation resulting from radiation or nuclear accident out of boarder, and after that reporting the emergency situation to relevant authorities on the national and international levels. Monitoring stations were installed using Gm tubes to cover boarder lines from south to north and east to west as follows: Damascus, Darra, Latakia, Tartous, Aleppo, Kamishly, Ragaa, and Qunitra. The following modes of communication: Telephone line, leased line, direct connection, and Syrian data network were used in the Syrian early network. This project was carried out in cooperation with IAEA under project no. RER/9/003. (author). 22 figs., 1 tab

  20. Timing and time signal distribution in digital communications networks

    Science.gov (United States)

    Kihara, Masami; Imaoka, Atushi

    1992-06-01

    The timing signal distribution characteristics of a digital communications network are evaluated to determine the Maximum Time Interval Error (MTIE) of the network; reference is made to the performance of network components such as transmission systems, slave clocks and timing distribution systems in intraoffices. The MTIE of each component is measured and used to determine the allowable MTIE of that component. The maximum number of slave node chains is shown to be 20. Time signal distribution performance is detailed. It is shown that time synchronization accuracy is of the order of submicroseconds between nodes separated by 2400 km over a two year period. For intra-office time signal distribution, the relative time accuracy is less than 3 nanoseconds using an 8 Mb/s round trip digital interface to connect a time signal supply in an office to dispersed equipment.

  1. Indoor infrared wireless communication system based on Ethernet network

    Science.gov (United States)

    Yang, Xin; Gong, Mali; Zhang, Kai; Zhang, Haitao; Yan, Ping; Jin, Wei; Jiang, Feng; Meng, Yu; Zou, Shanshan

    2002-12-01

    In this paper, we present an infrared wireless indoor communication system that bases on Ethernet network. The bit rate of Ethernet is 10Mbps, but after Manchester coding, in the physical layer the actual bit rate is 20Mbps. In our designs, the transmitter uses laser diodes (LDs). The transmitter consists of differential input circuit, LD driver circuit. The receiver consists of a coated truncated spherical concentrator whose field of view (FOV) is 40 degree, a large area Si PIN photo-detector followed by transimpedance amplifier, second-stage amplifier, low-pass filter (LPF), high-pass filter (HPF), limiting amplifier and differential output circuit. The network is constructed as a base-terminals configuration and two transit wavelengths are used for base and terminals respectively to avoid collision. Experimental testing was conducted in a room with size 5m × 5m × 3m and the network could work well.

  2. Chain-based communication in cylindrical underwater wireless sensor networks.

    Science.gov (United States)

    Javaid, Nadeem; Jafri, Mohsin Raza; Khan, Zahoor Ali; Alrajeh, Nabil; Imran, Muhammad; Vasilakos, Athanasios

    2015-01-01

    Appropriate network design is very significant for Underwater Wireless Sensor Networks (UWSNs). Application-oriented UWSNs are planned to achieve certain objectives. Therefore, there is always a demand for efficient data routing schemes, which can fulfill certain requirements of application-oriented UWSNs. These networks can be of any shape, i.e., rectangular, cylindrical or square. In this paper, we propose chain-based routing schemes for application-oriented cylindrical networks and also formulate mathematical models to find a global optimum path for data transmission. In the first scheme, we devise four interconnected chains of sensor nodes to perform data communication. In the second scheme, we propose routing scheme in which two chains of sensor nodes are interconnected, whereas in third scheme single-chain based routing is done in cylindrical networks. After finding local optimum paths in separate chains, we find global optimum paths through their interconnection. Moreover, we develop a computational model for the analysis of end-to-end delay. We compare the performance of the above three proposed schemes with that of Power Efficient Gathering System in Sensor Information Systems (PEGASIS) and Congestion adjusted PEGASIS (C-PEGASIS). Simulation results show that our proposed 4-chain based scheme performs better than the other selected schemes in terms of network lifetime, end-to-end delay, path loss, transmission loss, and packet sending rate.

  3. Seamless Data Services for Real Time Communication in a Heterogeneous Networks using Network Tracking and Management

    CERN Document Server

    T, Adiline Macriga

    2010-01-01

    Heterogeneous Networks is the integration of all existing networks under a single environment with an understanding between the functional operations and also includes the ability to make use of multiple broadband transport technologies and to support generalized mobility. It is a challenging feature for Heterogeneous networks to integrate several IP-based access technologies in a seamless way. The focus of this paper is on the requirements of a mobility management scheme for multimedia real-time communication services - Mobile Video Conferencing. Nowadays, the range of available wireless access network technologies includes cellular or wide-area wireless systems, such as cellular networks (GSM/GPRS/UMTS) or Wi-Max, local area Network or personal area wireless systems, comprising for example, WLAN (802.11 a/b/g) and Bluetooth. As the mobile video conferencing is considered, the more advanced mobile terminals are capable of having more than one interface active at the same time. In addition, the heterogeneity ...

  4. Impact of Changing Facets of Inter-firm Interactions on Manufacturing Excellence: A Social Network Perspective of Indian Automotive Industry.

    OpenAIRE

    Mamata Parhi

    2008-01-01

    The inherent complexity of the innovation process puts interaction among firms and their specificities concerning the patterns of interaction at the center-stage. Hence, an uncovering of the interactive pattern among firms in the industry may reveal many hidden patterns, viz., the existing dependence and dominance structure of firms and the evolving dynamical changes based their on. Guided by these, this paper studies the vertical relational structure of automotive and auto component firms in...

  5. Space Mobile Network: A Near Earth Communications and Navigation Architecture

    Science.gov (United States)

    Israel, David J.; Heckler, Gregory W.; Menrad, Robert J.

    2016-01-01

    This paper shares key findings of NASA's Earth Regime Network Evolution Study (ERNESt) team resulting from its 18-month effort to define a wholly new architecture-level paradigm for the exploitation of space by civil space and commercial sector organizations. Since the launch of Sputnik in October 1957 spaceflight missions have remained highly scripted activities from launch through disposal. The utilization of computer technology has enabled dramatic increases in mission complexity; but, the underlying premise that the diverse actions necessary to meet mission goals requires minute-by-minute scripting, defined weeks in advance of execution, for the life of the mission has remained. This archetype was appropriate for a "new frontier" but now risks overtly constraining the potential market-based opportunities for the innovation considered necessary to efficiently address the complexities associated with meeting communications and navigation requirements projected to be characteristics of the next era of space exploration: a growing number of missions in simultaneous execution, increased variance of mission types and growth in location/orbital regime diversity. The resulting ERNESt architectural cornerstone - the Space Mobile Network (SMN) - was envisioned as critical to creating an environment essential to meeting these future challenges in political, programmatic, technological and budgetary terms. The SMN incorporates technologies such as: Disruption Tolerant Networking (DTN) and optical communications, as well as new operations concepts such as User Initiated Services (UIS) to provide user services analogous to today's terrestrial mobile network user. Results developed in collaboration with NASA's Space Communications and Navigation (SCaN) Division and field centers are reported on. Findings have been validated via briefings to external focus groups and initial ground-based demonstrations. The SMN opens new niches for exploitation by the marketplace of mission

  6. Accepting Hybrid Networks of Evolutionary Processors with Special Topologies and Small Communication

    Directory of Open Access Journals (Sweden)

    Jürgen Dassow

    2010-08-01

    Full Text Available Starting from the fact that complete Accepting Hybrid Networks of Evolutionary Processors allow much communication between the nodes and are far from network structures used in practice, we propose in this paper three network topologies that restrict the communication: star networks, ring networks, and grid networks. We show that ring-AHNEPs can simulate 2-tag systems, thus we deduce the existence of a universal ring-AHNEP. For star networks or grid networks, we show a more general result; that is, each recursively enumerable language can be accepted efficiently by a star- or grid-AHNEP. We also present bounds for the size of these star and grid networks. As a consequence we get that each recursively enumerable can be accepted by networks with at most 13 communication channels and by networks where each node communicates with at most three other nodes.

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

    OpenAIRE

    Fang, Xi; Yang, Dejun; 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 ...

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

    CERN Document Server

    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

  9. Full-Duplex Communications in Large-Scale Cellular Networks

    KAUST Repository

    AlAmmouri, Ahmad

    2016-04-01

    In-band full-duplex (FD) communications have been optimistically promoted to improve the spectrum utilization and efficiency. However, the penetration of FD communications to the cellular networks domain is challenging due to the imposed uplink/downlink interference. This thesis presents a tractable framework, based on stochastic geometry, to study FD communications in multi-tier cellular networks. Particularly, we assess the FD communications effect on the network performance and quantify the associated gains. The study proves the vulnerability of the uplink to the downlink interference and shows that the improved FD rate gains harvested in the downlink (up to 97%) comes at the expense of a significant degradation in the uplink rate (up to 94%). Therefore, we propose a novel fine-grained duplexing scheme, denoted as α-duplex scheme, which allows a partial overlap between the uplink and the downlink frequency bands. We derive the required conditions to harvest rate gains from the α-duplex scheme and show its superiority to both the FD and half-duplex (HD) schemes. In particular, we show that the α-duplex scheme provides a simultaneous improvement of 28% for the downlink rate and 56% for the uplink rate. We also show that the amount of the overlap can be optimized based on the network design objective. Moreover, backward compatibility is an essential ingredient for the success of new technologies. In the context of in-band FD communication, FD base stations (BSs) should support HD users\\' equipment (UEs) without sacrificing the foreseen FD gains. The results show that FD-UEs are not necessarily required to harvest rate gains from FD-BSs. In particular, the results show that adding FD-UEs to FD-BSs offers a maximum of 5% rate gain over FD-BSs and HD-UEs case, which is a marginal gain compared to the burden required to implement FD transceivers at the UEs\\' side. To this end, we shed light on practical scenarios where HD-UEs operation with FD-BSs outperforms the

  10. Wireless Body Area Sensor Networks Signal Processing and Communication Framework: Survey on Sensing, Communication Technologies, Delivery and Feedback

    OpenAIRE

    Massudi Mahmuddin; Khalid A. Al-Saud; Amr Mohamed

    2012-01-01

    Problem statement: The Wireless Body Area Sensor Networks (WBASNs) is a wireless network used for communication among sensor nodes operating on or inside the human body in order to monitor vital body parameters and movements. This study surveys the state-of-the-art on Wireless Body Area Networks, discussing the major components of research in this area including physiological sensing and preprocessing, WBASNs communication techniques and data fusion for gathering data from sensors. In additio...

  11. Interplant communication of tomato plants through underground common mycorrhizal networks.

    Directory of Open Access Journals (Sweden)

    Yuan Yuan Song

    Full Text Available Plants can defend themselves to pathogen and herbivore attack by responding to chemical signals that are emitted by attacked plants. It is well established that such signals can be transferred through the air. In theory, plants can also communicate with each other through underground common mycorrhizal networks (CMNs that interconnect roots of multiple plants. However, until now research focused on plant-to-plant carbon nutrient movement and there is no evidence that defense signals can be exchanged through such mycorrhizal hyphal networks. Here, we show that CMNs mediate plant-plant communication between healthy plants and pathogen-infected tomato plants (Lycopersicon esculentum Mill.. After establishment of CMNs with the arbuscular mycorrhizal fungus Glomus mosseae between tomato plants, inoculation of 'donor' plants with the pathogen Alternaria solani led to increases in disease resistance and activities of the putative defensive enzymes, peroxidase, polyphenol oxidase, chitinase, β-1,3-glucanase, phenylalanine ammonia-lyase and lipoxygenase in healthy neighbouring 'receiver' plants. The uninfected 'receiver' plants also activated six defence-related genes when CMNs connected 'donor' plants challenged with A. solani. This finding indicates that CMNs may function as a plant-plant underground communication conduit whereby disease resistance and induced defence signals can be transferred between the healthy and pathogen-infected neighbouring plants, suggesting that plants can 'eavesdrop' on defence signals from the pathogen-challenged neighbours through CMNs to activate defences before being attacked themselves.

  12. Network security with openSSL cryptography for secure communications

    CERN Document Server

    Viega, John; Chandra, Pravir

    2002-01-01

    Most applications these days are at least somewhat network aware, but how do you protect those applications against common network security threats? Many developers are turning to OpenSSL, an open source version of SSL/TLS, which is the most widely used protocol for secure network communications.The OpenSSL library is seeing widespread adoption for web sites that require cryptographic functions to protect a broad range of sensitive information, such as credit card numbers and other financial transactions. The library is the only free, full-featured SSL implementation for C and C++, and it can be used programmatically or from the command line to secure most TCP-based network protocols.Network Security with OpenSSL enables developers to use this protocol much more effectively. Traditionally, getting something simple done in OpenSSL could easily take weeks. This concise book gives you the guidance you need to avoid pitfalls, while allowing you to take advantage of the library?s advanced features. And, inst...

  13. Strategies for Power Line Communications Smart Metering Network Deployment

    Directory of Open Access Journals (Sweden)

    Alberto Sendin

    2014-04-01

    Full Text Available Smart Grids are becoming a reality all over the world. Nowadays, the research efforts for the introduction and deployment of these grids are mainly focused on the development of the field of Smart Metering. This emerging application requires the use of technologies to access the significant number of points of supply (PoS existing in the grid, covering the Low Voltage (LV segment with the lowest possible costs. Power Line Communications (PLC have been extensively used in electricity grids for a variety of purposes and, of late, have been the focus of renewed interest. PLC are really well suited for quick and inexpensive pervasive deployments. However, no LV grid is the same in any electricity company (utility, and the particularities of each grid evolution, architecture, circumstances and materials, makes it a challenge to deploy Smart Metering networks with PLC technologies, with the Smart Grid as an ultimate goal. This paper covers the evolution of Smart Metering networks, together with the evolution of PLC technologies until both worlds have converged to project PLC-enabled Smart Metering networks towards Smart Grid. This paper develops guidelines over a set of strategic aspects of PLC Smart Metering network deployment based on the knowledge gathered on real field; and introduces the future challenges of these networks in their evolution towards the Smart Grid.

  14. Distributed communications and control network for robotic mining

    Science.gov (United States)

    Schiffbauer, William H.

    1989-01-01

    The application of robotics to coal mining machines is one approach pursued to increase productivity while providing enhanced safety for the coal miner. Toward that end, a network composed of microcontrollers, computers, expert systems, real time operating systems, and a variety of program languages are being integrated that will act as the backbone for intelligent machine operation. Actual mining machines, including a few customized ones, have been given telerobotic semiautonomous capabilities by applying the described network. Control devices, intelligent sensors and computers onboard these machines are showing promise of achieving improved mining productivity and safety benefits. Current research using these machines involves navigation, multiple machine interaction, machine diagnostics, mineral detection, and graphical machine representation. Guidance sensors and systems employed include: sonar, laser rangers, gyroscopes, magnetometers, clinometers, and accelerometers. Information on the network of hardware/software and its implementation on mining machines are presented. Anticipated coal production operations using the network are discussed. A parallelism is also drawn between the direction of present day underground coal mining research to how the lunar soil (regolith) may be mined. A conceptual lunar mining operation that employs a distributed communication and control network is detailed.

  15. Clustering and Beamforming for Efficient Communication in Wireless Sensor Networks

    Science.gov (United States)

    Porcel-Rodríguez, Francisco; Valenzuela-Valdés, Juan; Padilla, Pablo; Luna-Valero, Francisco; Luque-Baena, Rafael; López-Gordo, Miguel Ángel

    2016-01-01

    Energy efficiency is a critical issue for wireless sensor networks (WSNs) as sensor nodes have limited power availability. In order to address this issue, this paper tries to maximize the power efficiency in WSNs by means of the evaluation of WSN node networks and their performance when both clustering and antenna beamforming techniques are applied. In this work, four different scenarios are defined, each one considering different numbers of sensors: 50, 20, 10, five, and two nodes per scenario, and each scenario is randomly generated thirty times in order to statistically validate the results. For each experiment, two different target directions for transmission are taken into consideration in the optimization process (φ = 0° and θ = 45°; φ = 45°, and θ = 45°). Each scenario is evaluated for two different types of antennas, an ideal isotropic antenna and a conventional dipole one. In this set of experiments two types of WSN are evaluated: in the first one, all of the sensors have the same amount of power for communications purposes; in the second one, each sensor has a different amount of power for its communications purposes. The analyzed cases in this document are focused on 2D surface and 3D space for the node location. To the authors’ knowledge, this is the first time that beamforming and clustering are simultaneously applied to increase the network lifetime in WSNs. PMID:27556463

  16. Clustering and Beamforming for Efficient Communication in Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Francisco Porcel-Rodríguez

    2016-08-01

    Full Text Available Energy efficiency is a critical issue for wireless sensor networks (WSNs as sensor nodes have limited power availability. In order to address this issue, this paper tries to maximize the power efficiency in WSNs by means of the evaluation of WSN node networks and their performance when both clustering and antenna beamforming techniques are applied. In this work, four different scenarios are defined, each one considering different numbers of sensors: 50, 20, 10, five, and two nodes per scenario, and each scenario is randomly generated thirty times in order to statistically validate the results. For each experiment, two different target directions for transmission are taken into consideration in the optimization process (φ = 0° and θ = 45°; φ = 45°, and θ = 45°. Each scenario is evaluated for two different types of antennas, an ideal isotropic antenna and a conventional dipole one. In this set of experiments two types of WSN are evaluated: in the first one, all of the sensors have the same amount of power for communications purposes; in the second one, each sensor has a different amount of power for its communications purposes. The analyzed cases in this document are focused on 2D surface and 3D space for the node location. To the authors’ knowledge, this is the first time that beamforming and clustering are simultaneously applied to increase the network lifetime in WSNs.

  17. Clustering and Beamforming for Efficient Communication in Wireless Sensor Networks.

    Science.gov (United States)

    Porcel-Rodríguez, Francisco; Valenzuela-Valdés, Juan; Padilla, Pablo; Luna-Valero, Francisco; Luque-Baena, Rafael; López-Gordo, Miguel Ángel

    2016-01-01

    Energy efficiency is a critical issue for wireless sensor networks (WSNs) as sensor nodes have limited power availability. In order to address this issue, this paper tries to maximize the power efficiency in WSNs by means of the evaluation of WSN node networks and their performance when both clustering and antenna beamforming techniques are applied. In this work, four different scenarios are defined, each one considering different numbers of sensors: 50, 20, 10, five, and two nodes per scenario, and each scenario is randomly generated thirty times in order to statistically validate the results. For each experiment, two different target directions for transmission are taken into consideration in the optimization process (φ = 0° and θ = 45°; φ = 45°, and θ = 45°). Each scenario is evaluated for two different types of antennas, an ideal isotropic antenna and a conventional dipole one. In this set of experiments two types of WSN are evaluated: in the first one, all of the sensors have the same amount of power for communications purposes; in the second one, each sensor has a different amount of power for its communications purposes. The analyzed cases in this document are focused on 2D surface and 3D space for the node location. To the authors' knowledge, this is the first time that beamforming and clustering are simultaneously applied to increase the network lifetime in WSNs.

  18. A Survey of Underwater Acoustic Communication and Networking Techniques

    Directory of Open Access Journals (Sweden)

    Khan Rehan

    2013-01-01

    Full Text Available The study presents the details of recent developments and innovations in the field of Underwater Acoustic Communication (UWAC and networking that may be act as a requisite platform for the individuals who want to involve in the research of this emerging field. Ocean exploration/monitoring applications make design of robust UWAC and networking systems more demanding for recent researchers. The main objective of these studies is to establish a standard, low complex and real-time acoustic network having the capabilities to handle the extremely complex and continuously time varying nature of sea. During last decade, major contribution in this field has been carried out; many efficient methodologies and algorithms have also been proposed. In terms of physical layer, coherent MIMO-OFDM based communication is considered as feasible solution for the band limited/frequency selective underwater channel with more spectral efficiency, high data rates and reliable links. Considering the implications of complicated aquatic channel characteristics (extremely limited bandwidth, noise, Doppler spread, multipath, complex propagation delay, many researchers are also focusing for the developments of effective MAC protocols in terms of capacity and reduced consumption of power. Routing strategies that establish efficient data delivery paths in underwater environment is another demanding requirement. Designing of Transport layer protocol for fluctuated aquatic environment is an open research area.

  19. Clustering and Beamforming for Efficient Communication in Wireless Sensor Networks.

    Science.gov (United States)

    Porcel-Rodríguez, Francisco; Valenzuela-Valdés, Juan; Padilla, Pablo; Luna-Valero, Francisco; Luque-Baena, Rafael; López-Gordo, Miguel Ángel

    2016-01-01

    Energy efficiency is a critical issue for wireless sensor networks (WSNs) as sensor nodes have limited power availability. In order to address this issue, this paper tries to maximize the power efficiency in WSNs by means of the evaluation of WSN node networks and their performance when both clustering and antenna beamforming techniques are applied. In this work, four different scenarios are defined, each one considering different numbers of sensors: 50, 20, 10, five, and two nodes per scenario, and each scenario is randomly generated thirty times in order to statistically validate the results. For each experiment, two different target directions for transmission are taken into consideration in the optimization process (φ = 0° and θ = 45°; φ = 45°, and θ = 45°). Each scenario is evaluated for two different types of antennas, an ideal isotropic antenna and a conventional dipole one. In this set of experiments two types of WSN are evaluated: in the first one, all of the sensors have the same amount of power for communications purposes; in the second one, each sensor has a different amount of power for its communications purposes. The analyzed cases in this document are focused on 2D surface and 3D space for the node location. To the authors' knowledge, this is the first time that beamforming and clustering are simultaneously applied to increase the network lifetime in WSNs. PMID:27556463

  20. Automotive sensors

    Science.gov (United States)

    Marek, Jiri; Illing, Matthias

    2003-01-01

    Sensors are an essential component of most electronic systems in the car. They deliver input parameters for comfort features, engine and emission control as well as for the active and passive safety systems. New technologies such as silicon micromachining play an important role for the introduction of these sensors in all vehicle classes. The importance and use of these sensor technologies in today"s automotive applications will be shown in this article. Finally an outlook on important current developments and new functions in the car will be given.

  1. Secure and Authenticated Data Communication in Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Omar Alfandi

    2015-08-01

    Full Text Available Securing communications in wireless sensor networks is increasingly important as the diversity of applications increases. However, even today, it is equally important for the measures employed to be energy efficient. For this reason, this publication analyzes the suitability of various cryptographic primitives for use in WSNs according to various criteria and, finally, describes a modular, PKI-based framework for confidential, authenticated, secure communications in which most suitable primitives can be employed. Due to the limited capabilities of common WSN motes, criteria for the selection of primitives are security, power efficiency and memory requirements. The implementation of the framework and the singular components have been tested and benchmarked in our testbed of IRISmotes.

  2. A Traveling Wave based Communication Mechanism for Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Yoshiaki Taniguchi

    2007-09-01

    Full Text Available In this paper, we propose and evaluate a selforganizing communication mechanism for wireless sensor networks where a large number of sensor nodes are deployed. To accomplish application-oriented periodic communication without any centralized controls, we adopt traveling wave phenomena of a pulse-coupled oscillator model by regarding sensor nodes as oscillators and emission of radio signals as firing. We first investigate conditions of a phase-response curve to attain wave-formed firing patterns regardless of the initial phase of oscillators. We adopt the derived phase-response curve to accomplish the desired form of message propagation through local and mutual interactions among neighboring sensor nodes. Through simulation experiments, we confirm that our mechanism delivers sensor information to / from a designated node in a more energyefficient manner than other method, although it takes time to generate a traveling wave.

  3. Reconfigurable networking for coordinated multi-agent sensing and communications.

    Science.gov (United States)

    Sutton, Jeffrey P; Jamieson, Ian M D

    2002-12-01

    An implementation of a neurally-inspired system comprised of multiple mobile sensor-effector agents is described. Each agent has features of a complex neural network that is able to communicate and adjust its behavior depending upon a variety of parameters, including changes in the environment and the behavior of other agents. The system as a whole spatiotemporally reconfigures itself to perform coordinated behaviors not obtainable with single agents. Transient clustering of agents into functional subsystems to perform specific tasks generates a "system of systems" architecture. The interesting findings of this dynamic platform show that (a) the formation and dissolution of functional subsystems is a local phenomenon without the need for global control and (b) minimal intermittent communication among the agents can yield large-scale, coordinated, goal-driven behavior under a wide range of conditions. PMID:14983838

  4. Packet Skipping and Network Coding for Delay-Sensitive Network Communication

    CERN Document Server

    Aoun, Marc; Argyriou, Antonios; Denteneer, Dee; van der Stok, Peter

    2012-01-01

    We provide an analytical study of the impact of packet skipping and opportunistic network coding on the timely communication of messages through a single network element. In a first step, we consider a single-server queueing system with Poisson arrivals, exponential service times, and a single buffer position. Packets arriving at a network node have a fixed deadline before which they should reach the destination. To preserve server capacity, we introduce a thresholding policy, based on remaining time until deadline expiration, to decide whether to serve a packet or skip its service. The obtained goodput improvement of the system is derived, as well as the operating conditions under which thresholding can enhance performance. Subsequently, we focus our analysis on a system that supports network coding instead of thresholding. We characterize the impact of network coding at a router node on the delivery of packets associated with deadlines. We model the router node as a queueing system where packets arrive from...

  5. Data Gathering in Networks of Bacteria Colonies: Collective Sensing and Relaying Using Molecular Communication

    CERN Document Server

    Einolghozati, Arash; Beirami, Ahmad; Fekri, Faramarz

    2012-01-01

    The prospect of new biological and industrial applications that require communication in micro-scale, encourages research on the design of bio-compatible communication networks using networking primitives already available in nature. One of the most promising candidates for constructing such networks is to adapt and engineer specific types of bacteria that are capable of sensing, actuation, and above all, communication with each other. In this paper, we describe a new architecture for networks of bacteria to form a data collecting network, as in traditional sensor networks. The key to this architecture is the fact that the node in the network itself is a bacterial colony; as an individual bacterium (biological agent) is a tiny unreliable element with limited capabilities. We describe such a network under two different scenarios. We study the data gathering (sensing and multihop communication) scenario as in sensor networks followed by the consensus problem in a multi-node network. We will explain as to how th...

  6. 10 CFR 73.54 - Protection of digital computer and communication systems and networks.

    Science.gov (United States)

    2010-01-01

    ... 10 Energy 2 2010-01-01 2010-01-01 false Protection of digital computer and communication systems... provide high assurance that digital computer and communication systems and networks are adequately... licensee shall protect digital computer and communication systems and networks associated with: (i)...

  7. Network-based H∞ synchronization control of time-delay neural networks with communication constraints

    Science.gov (United States)

    Dong, Hui; Ling, Rongyao; Zhang, Dan

    2016-03-01

    This paper is concerned with the network-based H∞ synchronization control for a class of discrete time-delay neural networks, and attention is focused on how to reduce the communication rate since the communication resource is limited. Techniques such as the measurement size reduction, signal quantization and stochastic signal transmission are introduced to achieve the above goal. An uncertain switched system model is first proposed to capture the above-networked uncertainties. Based on the switched system theory and Lyapunov stability approach, a sufficient condition is obtained such that the closed-loop synchronization system is exponentially stable in the mean-square sense with a prescribed H∞ performance level. The controller gains are determined by solving a set of linear matrix inequalities (LMIs). A numerical example is finally presented to show the effectiveness of the proposed design method.

  8. Performance Modeling of Communication Networks with Markov Chains

    CERN Document Server

    Mo, Jeonghoon

    2010-01-01

    This book is an introduction to Markov chain modeling with applications to communication networks. It begins with a general introduction to performance modeling in Chapter 1 where we introduce different performance models. We then introduce basic ideas of Markov chain modeling: Markov property, discrete time Markov chain (DTMe and continuous time Markov chain (CTMe. We also discuss how to find the steady state distributions from these Markov chains and how they can be used to compute the system performance metric. The solution methodologies include a balance equation technique, limiting probab

  9. Security Challenges in Multicast Communication for Mobile Ad Hoc Network

    Directory of Open Access Journals (Sweden)

    S. Gunasekaran

    2010-01-01

    Full Text Available Problem statement: Multicasting communication network accepted a single message from an application and delivered copies of the message to multiple recipients at different locations. Recently, there has been an explosion of research literature on multicast communication environment. The objective of this study were to contribute the complexity of supporting current multicast applications, (i the lack of reliable multicast transport mechanisms at the network level and (ii the lack of network support for large scale multicast communication. The scaling problem of secure multicast key distribution compounded for the case where sender-specific keys need to be distributed to a group and required for sender-specific authentication of data traffic and minimize control overhead (iii compare RC4, AES-128,RS(2 and RS(3 computation time of both algorithms. Approach: Algorithms were collected and performed computation time. In general the multicast key distribution scheme implemented for distributing 128 bit session keys. Thus the Maximum Distance Separable Codes (MDS Codes needed for their encoding and decoding process. In rekeying scheme errors were occurred during over period of time or at a particular point of time and to eliminate all these errors in the level of encryption and decryption mechanism. The MDS codes played an important role in providing security services for multicast, such as traffic, integrity, authentication and confidentiality, is particularly problematic since it requires securely distributing a group (session key to each of a group’s receivers. Results: First we showed that internet multicasting algorithms based on reverse path forwarding were inherently unreliable and present a source-tree-based reliable multicasting scheme also. The new scheme proposed and used as an inter-gateway protocol and worked on top of the previously developed distance vector and link state internet routing schemes. Next, to support large scale

  10. Impact of Enforcement of Right of Communication through Information Network

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    On 27 October 2001, the Standing Committee of the People's Congress reviewed and passed the Amendment to the Copyright Law of the People's Republic of China. In Article 10 of the amended Copyright Law as of 2001 has been incorporated a new subject matter under the copyright protection: the right of communication through information network, that is, the right to make a work available to the public by wire or by wireless means, so that people may have access to the work from a place and at a time individu...

  11. Recursive estimation algorithms for power controls of wireless communication networks

    Institute of Scientific and Technical Information of China (English)

    Gang George YIN; Chin-An TAN; Le Yi WANG; Chengzhong XU

    2008-01-01

    Power control problems for wireless communication networks are investigated in direct-sequence codedivision multiple-access(DS/CDMA)channels.It is shown that the underlying problem can be formulated as a constrained optimization problem in a stochastic framework.For effective solutions to this optimization problem in real time,recursive algorithms of stochastic approximation type are developed that can solve the problem with unknown system components.Under broad conditions,convergence of the algorithms is established by using weak convergence methods.

  12. Analysis of Network Performance for Computer Communication Systems with Benchmark

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    This paper introduced a performance evaluating approach of computer communication system based on the simulation and measurement technology, and discussed its evaluating models. The result of our experiment showed that the outcome of practical measurement on Ether-LAN fitted in well with the theoreticai analysis. The approach we presented can be used to define various kinds of artificially simulated load models conveniently, build all kinds of network application environments in a flexible way, and exert sufficientiy the widely-used and high-precision features of the traditional simulation technology and the reality,reliability, adaptability features of measurement technology.

  13. Future mobile communications LTE optimization and mobile network virtualization

    CERN Document Server

    Zaki, Yasir

    2012-01-01

    The key to a successful future mobile communication system lies in the design of its radio scheduler. One of the key challenges of the radio scheduler is how to provide the right balance between Quality of Service (QoS) guarantees and the overall system performance. Yasir Zaki proposes innovative solutions for the design of the Long Term Evolution (LTE) radio scheduler and presents several LTE radio scheduler analytical models that can be used as efficient tools for radio dimensioning. The author also introduces a novel wireless network virtualization framework and highlights the potential gai

  14. TRAFFIC CONTROLLED-DEDICATED SHORT RANGE COMMUNICATION: A SECURE COMMUNICATION USING TRAFFIC CONTROLLED DEDICATED SHORT RANGE COMMUNICATION MODEL IN VEHICULAR AD HOC NETWORKS FOR SAFETY RELATED SERVICES

    OpenAIRE

    K. Chandramohan; P. Kamalakkannan

    2014-01-01

    To increase the road safety and secure communication among the vehicles in the network environment, Dedicated Short Range Communication (DSRC) is followed. Nowadays, research over DSRC is dramatically increased for enhancing the road safety applications. The main task of DSRC is to protect the vehicles by communicating the warning message regarding the vehicle changing conditions, traffic occurrence and dangers over the road in the network. So, it is necessary to maintain the accurate communi...

  15. SPECIFICITY OF COMMUNICATION DOCTOR – PATIENT, ONLINE, THROUGH SOCIAL NETWORKS

    Directory of Open Access Journals (Sweden)

    Florin-Alexandru LUCA

    2014-12-01

    Full Text Available A survey in 2013 of Division Market Research Group Rentrop Straton Romanian-German - "state services and private clinics. Comparative Analysis ", highlights the fact that into urban population in Romania, the internet is the most popular source of information on health services. According to the survey, 81.9% of respondents use the Internet to find out about the best doctors available to them. Preferences of respondents to the online environment as the main source of information translates into ease of access and the possibility of interaction, but also trust recommendations based on personal experiences, recommendations can be found through discussion forums, mostly or comments left on pages on social networking sites. In the present study we try to emphasize the specificity of communication physician - patient online through social networks.

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

    Science.gov (United States)

    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.

  17. Using Cellular Communication Networks To Detect Air Pollution.

    Science.gov (United States)

    David, Noam; Gao, H Oliver

    2016-09-01

    Accurate real time monitoring of atmospheric conditions at ground level is vital for hazard warning, meteorological forecasting, and various environmental applications required for public health and safety. However, conventional monitoring facilities are costly and often insufficient, for example, since they are not representative of the larger space and are not deployed densely enough in the field. There have been numerous scientific works showing the ability of commercial microwave links that comprise the data transmission infrastructure in cellular communication networks to monitor hydrometeors as a potential complementary solution. However, despite the large volume of research carried out in this emerging field during the past decade, no study has shown the ability of the system to provide critical information regarding air quality. Here we reveal the potential for identifying atmospheric conditions prone to air pollution by detecting temperature inversions that trap pollutants at ground level. The technique is based on utilizing standard signal measurements from an existing cellular network during routine operation.

  18. Integrating Space Communication Network Capabilities via Web Portal Technologies

    Science.gov (United States)

    Johnston, Mark D.; Lee, Carlyn-Ann; Lau, Chi-Wung; Cheung, Kar-Ming; Levesque, Michael; Carruth, Butch; Coffman, Adam; Wallace, Mike

    2014-01-01

    We have developed a service portal prototype as part of an investigation into the feasibility of using Java portlet technology as a means of providing integrated access to NASA communications network services. Portal servers provide an attractive platform for this role due to the various built-in collaboration applications they can provide, combined with the possibility to develop custom inter-operating portlets to extent their functionality while preserving common presentation and behavior. This paper describes various options for integration of network services related to planning and scheduling, and results based on use of a popular open-source portal framework. Plans are underway to develop an operational SCaN Service Portal, building on the experiences reported here.

  19. Using Cellular Communication Networks To Detect Air Pollution.

    Science.gov (United States)

    David, Noam; Gao, H Oliver

    2016-09-01

    Accurate real time monitoring of atmospheric conditions at ground level is vital for hazard warning, meteorological forecasting, and various environmental applications required for public health and safety. However, conventional monitoring facilities are costly and often insufficient, for example, since they are not representative of the larger space and are not deployed densely enough in the field. There have been numerous scientific works showing the ability of commercial microwave links that comprise the data transmission infrastructure in cellular communication networks to monitor hydrometeors as a potential complementary solution. However, despite the large volume of research carried out in this emerging field during the past decade, no study has shown the ability of the system to provide critical information regarding air quality. Here we reveal the potential for identifying atmospheric conditions prone to air pollution by detecting temperature inversions that trap pollutants at ground level. The technique is based on utilizing standard signal measurements from an existing cellular network during routine operation. PMID:27490182

  20. Cascaded Network Body Channel Model for Intrabody Communication.

    Science.gov (United States)

    Wang, Hao; Tang, Xian; Choy, Chiu Sing; Sobelman, Gerald E

    2016-07-01

    Intrabody communication has been of great research interest in recent years. This paper proposes a novel, compact but accurate body transmission channel model based on RC distribution networks and transmission line theory. The comparison between simulation and measurement results indicates that the proposed approach accurately models the body channel characteristics. In addition, the impedance-matching networks at the transmitter output and the receiver input further maximize the power transferred to the receiver, relax the receiver complexity, and increase the transmission performance. Based on the simulation results, the power gain can be increased by up to 16 dB after matching. A binary phase-shift keying modulation scheme is also used to evaluate the bit-error-rate improvement. PMID:26111404

  1. Cascaded Network Body Channel Model for Intrabody Communication.

    Science.gov (United States)

    Wang, Hao; Tang, Xian; Choy, Chiu Sing; Sobelman, Gerald E

    2016-07-01

    Intrabody communication has been of great research interest in recent years. This paper proposes a novel, compact but accurate body transmission channel model based on RC distribution networks and transmission line theory. The comparison between simulation and measurement results indicates that the proposed approach accurately models the body channel characteristics. In addition, the impedance-matching networks at the transmitter output and the receiver input further maximize the power transferred to the receiver, relax the receiver complexity, and increase the transmission performance. Based on the simulation results, the power gain can be increased by up to 16 dB after matching. A binary phase-shift keying modulation scheme is also used to evaluate the bit-error-rate improvement.

  2. Communication in Change - Voice over IP in Safety and Security Critical Communication Networks

    Science.gov (United States)

    Zeilinger, Heimo; Sevcik, Berndt; Turek, Thomas; Zucker, Gerhard

    During the last decade communication technology has changed rapidly. Due to its decreasing costs and rising expansion, IP (Internet Protocol) technology has found its way to areas that have long been the domain of public-switched telephone networks (PSTN). Voice over IP (VoIP) applications are widely used not only for phone calls or common Internet conferences, but also tend to be used for safety critical communication applications. Hence security and safety topics arise, which pose new challenges in this area of research. The authors are convinced that new issues on the network layer as well as on the application layer require detailed analysis. Hence this paper gives an overview on latest developments in this area, and states the authors’ view on this topic. Thereby safety and security issues are faced from different abstraction layers. On the one hand the network layer and on the other hand the application layer focusing on middleware systems in the area of service oriented architectures (SOAs).

  3. Simulation study of unmanned aerial vehicle communication networks addressing bandwidth disruptions

    Science.gov (United States)

    Wei, Sixiao; Ge, Linqiang; Yu, Wei; Chen, Genshe; Pham, Khanh; Blasch, Erik; Shen, Dan; Lu, Chao

    2014-06-01

    To date, Unmanned Aerial Vehicles (UAVs) have been widely used for numerous applications. UAVs can directly connect to ground stations or satellites to transfer data. Multiple UAVs can communicate and cooperate with each other and then construct an ad-hoc network. Multi-UAV systems have the potential to provide reliable and timely services for end users in addition to satellite networks. In this paper, we conduct a simulation study for evaluating the network performance of multi-UAV systems and satellite networks using the ns-2 networking simulation tool. Our simulation results show that UAV communication networks can achieve better network performance than satellite networks and with a lower cost and increased timeliness. We also investigate security resiliency of UAV networks. As a case study, we simulate false data injection attacks against UAV communication networks in ns-2 and demonstrate the impact of false data injection attacks on network performance.

  4. Dynamic behavior of shortest path routing algorithms for communication networks

    Science.gov (United States)

    Bertsekas, D. P.

    1980-06-01

    Several proposed routing algorithms for store and forward communication networks, including one currently in operation in the ARPANET, route messages along shortest paths computed by using some set of link lengths. When these lengths depend on current traffic conditions as they must in an adaptive algorithm, dynamic behavior questions such as stability convergence, and speed of convergence are of interest. This paper is the first attempt to analyze systematically these issues. It is shown that minimum queuing delay path algorithms tend to exhibit violent oscillatory behavior in the absence of a damping mechanism. The oscillations can be damped by means of several types of schemes, two of which are analyzed in this paper. In the first scheme a constant bias is added to the queuing delay thereby providing a preference towards paths with a small number of links. In the second scheme the effects of several past routings are averaged as, for example, when the link lengths are computed and communicated asynchronously throughout the network.

  5. Confidential Communication Through Chaos Encryption in Wireless Sensor Network

    Institute of Scientific and Technical Information of China (English)

    CHEN Shuai; ZHONG Xian-xin

    2007-01-01

    A new byte block cipher algorithm with discrete chaos and Feistel structure has been studied for confidential communication in wireless sensor network to improve security. After permutation, the byte block was encrypted through a Feistel structure in multiple turns and afterwards replaced again. The child keys are the composite sequence of discrete chaos and linear congruence sequences. Both the plain text and cipher text are of 8 bits. The number of keys is alterable. A nonlinear encryption function in the Feistel structure with chaos was constructed. The cipher algorithm was realized in the Micaz node,and the confidential communication experiment in wireless sensor network was completed successfully. Additional ROM memory required for the cipher algorithm is 4144 bytes and an additional RAM memory 61 bytes. The cipher algorithm is nonlinear chaos and the Feistel structure holds the best of the RC6, DES and SKIPJACK cipher algorithms.The result shows that the algorithm needs a little memory and is safe at a high level.

  6. Communication Network Architectures for Smart-Wind Power Farms

    Directory of Open Access Journals (Sweden)

    Mohamed A. Ahmed

    2014-06-01

    Full Text Available Developments in the wind power industry have enabled a new generation of wind turbines with longer blades, taller towers, higher efficiency, and lower maintenance costs due to the maturity of related technologies. Nevertheless, wind turbines are still blind machines because the control center is responsible for managing and controlling individual wind turbines that are turned on or off according to demand for electricity. In this paper, we propose a communication network architecture for smart-wind power farms (Smart-WPFs. The proposed architecture is designed for wind turbines to communicate directly and share sensing data in order to maximize power generation, WPF availability, and turbine efficiency. We also designed a sensor data frame structure to carry sensing data from different wind turbine parts such as the rotor, transformer, nacelle, etc. The data frame includes a logical node ID (LNID, sensor node ID (SNID, sensor type (ST, and sensor data based on the International Electrotechnical Commission (IEC 61400-25 standard. We present an analytical model that describes upstream traffic between the wind turbines and the control center. Using a queueing theory approach, the upstream traffic is evaluated in view of bandwidth utilization and average queuing delay. The performance of the proposed network architectures are evaluated by using analytical and simulation models.

  7. An Interdisciplinary Network Making Progress on Climate Change Communication

    Science.gov (United States)

    Spitzer, W.; Anderson, J. C.; Bales, S.; Fraser, J.; Yoder, J. A.

    2012-12-01

    , social scientists, Ph.D. students studying oceanography, and staff from more than 20 institutions that teach science to the public came together in these learning groups. Most participants were motivated to create new or revised training or public programs based on lessons learned together. The success of this program rests on a twofold approach that combines collaborative learning with a cognitive and social sciences research based approach to communications. The learning process facilitated trust and experimentation among co-learners to practice applications for communications that has continued beyond the study circle experience through the networks established during the process. Examples drawn from the study circle outputs suggest that this approach could have a transformative impact on informal science education on a broad scale. Ultimately, we envision informal science interpreters as "vectors" for effective science communication, ocean and climate scientists with enhanced communication skills, and increased public demand for explanation and dialogue about global issues.

  8. Organizational structure and communication networks in a university environment.

    Science.gov (United States)

    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. PMID:20866686

  9. A Scheduling Algorithm Based on Communication Delay for Wireless Network Control System

    Directory of Open Access Journals (Sweden)

    Jun Wang

    2012-09-01

    Full Text Available In this study, a scheduling algorithm based on communication delay is proposed. This scheduling algorithm can tolerate delay of periodic communication tasks in wireless network control system. It resolves real-time problem of periodic communication tasks in wireless network control system and partly reduces overtime phenomenon of periodic communication tasks caused by delay in wireless network. At the same time, the nonlinear programming model is built for solving scheduling timetable based on the proposed scheduling algorithm. Finally, the performance of the proposed scheduling algorithm is evaluated by an application example. The statistics results show that it is more effective than traditional scheduling algorithms in wireless network control system.

  10. Calculated pKa Variations Expose Dynamic Allosteric Communication Networks.

    Science.gov (United States)

    Lang, Eric J M; Heyes, Logan C; Jameson, Geoffrey B; Parker, Emily J

    2016-02-17

    Allosteric regulation of protein function, the process by which binding of an effector molecule provokes a functional response from a distal site, is critical for metabolic pathways. Yet, the way the allosteric signal is communicated remains elusive, especially in dynamic, entropically driven regulation mechanisms for which no major conformational changes are observed. To identify these dynamic allosteric communication networks, we have developed an approach that monitors the pKa variations of ionizable residues over the course of molecular dynamics simulations performed in the presence and absence of an allosteric regulator. As the pKa of ionizable residues depends on their environment, it represents a simple metric to monitor changes in several complex factors induced by binding an allosteric effector. These factors include Coulombic interactions, hydrogen bonding, and solvation, as well as backbone motions and side chain fluctuations. The predictions that can be made with this method concerning the roles of ionizable residues for allosteric communication can then be easily tested experimentally by changing the working pH of the protein or performing single point mutations. To demonstrate the method's validity, we have applied this approach to the subtle dynamic regulation mechanism observed for Neisseria meningitidis 3-deoxy-d-arabino-heptulosonate 7-phosphate synthase, the first enzyme of aromatic biosynthesis. We were able to identify key communication pathways linking the allosteric binding site to the active site of the enzyme and to validate these findings experimentally by reestablishing the catalytic activity of allosterically inhibited enzyme via modulation of the working pH, without compromising the binding affinity of the allosteric regulator.

  11. Design and analysis of communication protocols for quantum repeater networks

    Science.gov (United States)

    Jones, Cody; Kim, Danny; Rakher, Matthew T.; Kwiat, Paul G.; Ladd, Thaddeus D.

    2016-08-01

    We analyze how the performance of a quantum-repeater network depends on the protocol employed to distribute entanglement, and we find that the choice of repeater-to-repeater link protocol has a profound impact on entanglement-distribution rate as a function of hardware parameters. We develop numerical simulations of quantum networks using different protocols, where the repeater hardware is modeled in terms of key performance parameters, such as photon generation rate and collection efficiency. These parameters are motivated by recent experimental demonstrations in quantum dots, trapped ions, and nitrogen-vacancy centers in diamond. We find that a quantum-dot repeater with the newest protocol (‘MidpointSource’) delivers the highest entanglement-distribution rate for typical cases where there is low probability of establishing entanglement per transmission, and in some cases the rate is orders of magnitude higher than other schemes. Our simulation tools can be used to evaluate communication protocols as part of designing a large-scale quantum network.

  12. Detailed temporal structure of communication networks in groups of songbirds.

    Science.gov (United States)

    Stowell, Dan; Gill, Lisa; Clayton, David

    2016-06-01

    Animals in groups often exchange calls, in patterns whose temporal structure may be influenced by contextual factors such as physical location and the social network structure of the group. We introduce a model-based analysis for temporal patterns of animal call timing, originally developed for networks of firing neurons. This has advantages over cross-correlation analysis in that it can correctly handle common-cause confounds and provides a generative model of call patterns with explicit parameters for the influences between individuals. It also has advantages over standard Markovian analysis in that it incorporates detailed temporal interactions which affect timing as well as sequencing of calls. Further, a fitted model can be used to generate novel synthetic call sequences. We apply the method to calls recorded from groups of domesticated zebra finch (Taeniopygia guttata) individuals. We find that the communication network in these groups has stable structure that persists from one day to the next, and that 'kernels' reflecting the temporal range of influence have a characteristic structure for a calling individual's effect on itself, its partner and on others in the group. We further find characteristic patterns of influences by call type as well as by individual.

  13. Distributed user-centric scheduling for visible light communication networks.

    Science.gov (United States)

    Chen, Lingjiao; Wang, Jiaheng; Zhou, Jiantao; Ng, Derrick Wing Kwan; Schober, Robert; Zhao, Chunming

    2016-07-11

    Visible light communication (VLC) networks, consisting of multiple light-emitting diodes (LEDs) acting as optical access points (APs), can provide low-cost high-rate data transmission to multiple users simultaneously in indoor environments. However, the performance of VLC networks is severely limited by the interference between different users. In this paper, we establish a distributed user-centric scheduling framework based on stable marriage theory, and propose a novel decentralized scheduling method to manage interference by forming flexible amorphous cells for all users. The proposed scheduling method has provable low computational complexity and requires only the exchange of a few 1-bit messages between the APs and the users but not the feedback of the channel state information of the entire network. We further show that the proposed method can achieve both user-wise and system-wise optimality as well as a certain level of fairness. Simulation results indicate that our decentralized user-centric scheduling method outperforms existing centralized approaches in terms of throughput, fairness, and computational complexity. PMID:27410830

  14. Directedness of information flow in mobile phone communication networks

    CERN Document Server

    Peruani, Fernando; 10.1371/journal.pone.0028860

    2013-01-01

    Without having direct access to the information that is being exchanged, traces of information flow can be obtained by looking at temporal sequences of user interactions. These sequences can be represented as causality trees whose statistics result from a complex interplay between the topology of the underlying (social) network and the time correlations among the communications. Here, we study causality trees in mobile-phone data, which can be represented as a dynamical directed network. This representation of the data reveals the existence of super-spreaders and super-receivers. We show that the tree statistics, respectively the information spreading process, are extremely sensitive to the in-out degree correlation exhibited by the users. We also learn that a given information, e.g., a rumor, would require users to retransmit it for more than 30 hours in order to cover a macroscopic fraction of the system. Our analysis indicates that topological node-node correlations of the underlying social network, while ...

  15. Directedness of information flow in mobile phone communication networks.

    Directory of Open Access Journals (Sweden)

    Fernando Peruani

    Full Text Available Without having direct access to the information that is being exchanged, traces of information flow can be obtained by looking at temporal sequences of user interactions. These sequences can be represented as causality trees whose statistics result from a complex interplay between the topology of the underlying (social network and the time correlations among the communications. Here, we study causality trees in mobile-phone data, which can be represented as a dynamical directed network. This representation of the data reveals the existence of super-spreaders and super-receivers. We show that the tree statistics, respectively the information spreading process, are extremely sensitive to the in-out degree correlation exhibited by the users. We also learn that a given information, e.g., a rumor, would require users to retransmit it for more than 30 hours in order to cover a macroscopic fraction of the system. Our analysis indicates that topological node-node correlations of the underlying social network, while allowing the existence of information loops, they also promote information spreading. Temporal correlations, and therefore causality effects, are only visible as local phenomena and during short time scales. Consequently, the very idea that there is (intentional information spreading beyond a small vecinity is called into question. These results are obtained through a combination of theory and data analysis techniques.

  16. Switching scheme of data communication network for safety system in nuclear power plant

    International Nuclear Information System (INIS)

    To develop a communication network architecture for the safety system of a nuclear power plant, we have determined five essential design requirements for the communication network for safety-critical systems such as a status-based architecture, deterministic scheme, separation and isolation, high reliability, verification and validation. Also, the analysis of commercial technology to design elements shows that a circuit switched network is adequate for a safety system network. In this paper, a data communication network switching scheme for safety systems is newly proposed based on a circuit switching network with time division multiplexing bus technology which is considered as adequate for the essence of the design requirements and the design elements. The proposed communication network switching scheme was confirmed to satisfy the requirements and the possibility of implementation by applying the network design of the reactor protection system of nuclear power plant. (authors)

  17. Inter-vehicle-communications based on ad hoc networking principles. The FleetNet Project

    OpenAIRE

    Franz, Walter; Hartenstein, Hannes; Mauve, Martin

    2005-01-01

    Vehicular Ad Hoc Networks (VANETs) represent an emerging topic in wireless communication and networking. VANETs are currently receiving a lot of attention due to their promise of considerably increasing safety and comfort while being on the road. High mobility, adverse channel conditions, and market introduction are some of the key challenges one has to deal with when designing these spontaneous networks. Inter-Vehicle-Communications Based on Ad Hoc Networking Principles covers results and ac...

  18. A mars communication constellation for human exploration and network science

    Science.gov (United States)

    Castellini, Francesco; Simonetto, Andrea; Martini, Roberto; Lavagna, Michèle

    2010-01-01

    This paper analyses the possibility of exploiting a small spacecrafts constellation around Mars to ensure a complete and continuous coverage of the planet, for the purpose of supporting future human and robotic operations and taking advantage of optical transmission techniques. The study foresees such a communications mission to be implemented at least after 2020 and a high data-rate requirement is imposed for the return of huge scientific data from massive robotic exploration or to allow video transmissions from a possible human outpost. In addition, the set-up of a communication constellation around Mars would give the opportunity of exploiting this multi-platform infrastructure to perform network science, that would largely increase our knowledge of the planet. The paper covers all technical aspects of a feasibility study performed for the primary communications mission. Results are presented for the system trade-offs, including communication architecture, constellation configuration and transfer strategy, and the mission analysis optimization, performed through the application of a multi-objective genetic algorithm to two models of increasing difficulty for the low-thrust trajectory definition. The resulting communication architecture is quite complex and includes six 530 kg spacecrafts on two different orbital planes, plus one redundant unit per plane, that ensure complete coverage of the planet’s surface; communications between the satellites and Earth are achieved through optical links, that allow lower mass and power consumption with respect to traditional radio-frequency technology, while inter-satellite links and spacecrafts-to-Mars connections are ensured by radio transmissions. The resulting data-rates for Earth-Mars uplink and downlink, satellite-to-satellite and satellite-to-surface are respectively 13.7 Mbps, 10.2 Mbps, 4.8 Mbps and 4.3 Mbps, in worst-case. Two electric propulsion modules are foreseen, to be placed on a C3˜0 escape orbit with two

  19. Operationalising luxury in the premium automotive industry

    OpenAIRE

    Bridle, Bernadette

    2010-01-01

    This thesis presents an Action Research project investigating the use of customers’ perceptions of premium and luxury cars within the premium automotive industry. The research was sponsored by Jaguar Land Rover (JLR), a UK-based automotive manufacturer. An inductive, phenomenological approach was adopted in which JLR’s Premiumness Research Programme (PRP) was used as a case study to build an understanding of the consumer’s perception of luxury, to discover how to communic...

  20. Enhanced TCP for maritime communications over satellite network

    Science.gov (United States)

    Zong, Liang; Du, Wencai; Bai, Yong

    2014-10-01

    For maritime communications over satellite network, TCP performance is essential for data transmissions. TCP ADaLR is congestion control algorithm that the sender judgments the relevant window change and measures roundtrip time to control congestion window. It can adapt to the characteristics of the satellite link and improve the performance of TCP than conventional TCP. However, it does not take into account distinction of random packet loss and congestion loss like TCP Veno. In this paper, we propose further enhancement of TCP ADaLR, called TCP ADaLR+, that can distinguish between random packet loss and congestion loss. The improved performance of proposed TCP ADaLR+ is demonstrated by simulations.

  1. Increasing capacity of baseband digital data communication networks

    Science.gov (United States)

    Frankel, Robert S.; Herman, Alexander

    1985-01-01

    This invention provides broadband network capabilities for baseband digital collision detection transceiver equipment for communication between a plurality of data stations by affording simultaneous transmission of multiple channels over a broadband pass transmission link such as a coaxial cable. Thus, a fundamental carrier wave is transmitted on said link, received at local data stations and used to detect signals on different baseband channels for reception. For transmission the carrier wave typically is used for segregating a plurality of at least two transmission channels into typically single sideband upper and lower pass bands of baseband bandwidth capability adequately separated with guard bands to permit simple separation for receiving by means of pass band filters, etc.

  2. Highly survivable communications: Complementary media packet switched networks

    Science.gov (United States)

    Yavuz, D.; Eken, F.; Karavassilis, N.

    1994-07-01

    The requirement for highly survivable communications (HSC) for essential command functions in military operations does not need any justification. The ability to communicate under extreme jamming levels and adverse propagation conditions, including high altitude nuclear events, is a very important requirement. There are also many natural disaster related requirements that also need such highly survivable communications. The prevalent and in a sense classical, approach to provide highly assured connectivity can be summarized as follows: Take a particular propagation medium and try to obtain the ultimate performance from it. There are many examples of this philosophy some successful, most not. Our approach, on the other hand, is to use complementary multi-media or mixed-media where communication links utilizing essentially commercial-off-the-shelf (COTS) equipment are integrated using packet radio (PR) techniques. There is also, in our view, an even more fundamental, recently discovered consideration why the expectation of continuous incremental refinement of a system using a given single media may be be achievable. This is derived from the theory of 'deterministic uncertainty' or more popularly known as 'theory of CHAOS', systems whose state space behavior has fractal characteristics. We will elaborate on this novel argument. Complementary multi-media approach has been the focus for all HSC communications activities at STC since 1982. The original STC studies and prototypes were in response to requirements of broadcasting (i.e., one-way transmission) information. A high frequency (HF)/meteorburst (MB) system was developed/prototyped/tested demonstrating the cost effectiveness of the approach. These results are reviewed. More recently, in 1992 STC has completed the development/test of an Open Systems Interconnection (OSI) HF packet radio protocol as no such open or non-proprietary protocol exists. This protocol has been fully tested, documented and made available to

  3. Data communication requirements for the advanced NAS network

    Science.gov (United States)

    Levin, Eugene; Eaton, C. K.; Young, Bruce

    1986-01-01

    The goal of the Numerical Aerodynamic Simulation (NAS) Program is to provide a powerful computational environment for advanced research and development in aeronautics and related disciplines. The present NAS system consists of a Cray 2 supercomputer connected by a data network to a large mass storage system, to sophisticated local graphics workstations, and by remote communications to researchers throughout the United States. The program plan is to continue acquiring the most powerful supercomputers as they become available. In the 1987/1988 time period it is anticipated that a computer with 4 times the processing speed of a Cray 2 will be obtained and by 1990 an additional supercomputer with 16 times the speed of the Cray 2. The implications of this 20-fold increase in processing power on the data communications requirements are described. The analysis was based on models of the projected workload and system architecture. The results are presented together with the estimates of their sensitivity to assumptions inherent in the models.

  4. Antenna Arrays and Automotive Applications

    CERN Document Server

    Rabinovich, Victor

    2013-01-01

    This book throws a lifeline to designers wading through mounds of antenna array patents looking for the most suitable systems for their projects. Drastically reducing the research time required to locate solutions to the latest challenges in automotive communications, it sorts and systematizes material on cutting-edge antenna arrays that feature multi-element communication systems with enormous potential for the automotive industry. These new systems promise to make driving safer and more efficient, opening up myriad applications, including vehicle-to-vehicle traffic that prevents collisions, automatic toll collection, vehicle location and fine-tuning for cruise control systems. This book’s exhaustive coverage begins with currently deployed systems, frequency ranges and key parameters. It proceeds to examine system geometry, analog and digital beam steering technology (including "smart" beams formed in noisy environments), maximizing signal-to-noise ratios, miniaturization, and base station technology that ...

  5. Rapid 3D Modeling and Parts Recognition on Automotive Vehicles Using a Network of RGB-D Sensors for Robot Guidance

    Directory of Open Access Journals (Sweden)

    Alberto Chávez-Aragón

    2013-01-01

    Full Text Available This paper presents an approach for the automatic detection and fast 3D profiling of lateral body panels of vehicles. The work introduces a method to integrate raw streams from depth sensors in the task of 3D profiling and reconstruction and a methodology for the extrinsic calibration of a network of Kinect sensors. This sensing framework is intended for rapidly providing a robot with enough spatial information to interact with automobile panels using various tools. When a vehicle is positioned inside the defined scanning area, a collection of reference parts on the bodywork are automatically recognized from a mosaic of color images collected by a network of Kinect sensors distributed around the vehicle and a global frame of reference is set up. Sections of the depth information on one side of the vehicle are then collected, aligned, and merged into a global RGB-D model. Finally, a 3D triangular mesh modelling the body panels of the vehicle is automatically built. The approach has applications in the intelligent transportation industry, automated vehicle inspection, quality control, automatic car wash systems, automotive production lines, and scan alignment and interpretation.

  6. AQM Algorithm with Adaptive Reference Queue Threshold for Communication Networks

    Directory of Open Access Journals (Sweden)

    Liming Chen

    2012-09-01

    Full Text Available Nowadays, congestion in communication networks has been more intractable than ever before due to the explosive growth of network scale and multimedia traffic. Active queue management (AQM algorithms had been proposed to alleviate congestion to improve quality of service (QoS, but existing algorithms often suffer from some flaws in one aspect or another. In this paper, a novel AQM algorithm with adaptive reference queue threshold (ARTAQM is proposed of which the main innovative contributions are recounted as follows. First, traffic is predicted to calculate the packet loss ratio (PLR and the traffic rate based on traffic prediction algorithm. Second, by means of periodical measurements, a weighted PLR is obtained to dynamically adjust packet dropping probability in ARTAQM algorithm. Third, ARTAQM algorithm runs in both coarse and fine granularities. In coarse granularity, the mismatch of the predicted traffic rate and link capacity can adjusts the reference queue length in every period, while in fine granularity, reference queue remains fixed and the  instantaneous queue is adjusted packet by packet in one period. Simulation results indicate that ARTAQM algorithm not only maintains stable queue and fast response speed, but has lower PLR and higher link utilization as well.

  7. Throughput, Energy and Overhead of Multicast Device-to-Device Communications with Network Coded Cooperation

    DEFF Research Database (Denmark)

    Hernandez, Nestor; Heide, Janus; Roetter, Daniel Enrique Lucani;

    2016-01-01

    Cooperation strategies in mobile networks typically rely in short range technologies, like LTE-A Device to Device (D2D) communications, for data exchange between devices forming mobile clouds. These communications provide a better device experience since the clouds offload the network. Nevertheless...

  8. Teaching Students How to Integrate and Assess Social Networking Tools in Marketing Communications

    Science.gov (United States)

    Schlee, Regina Pefanis; Harich, Katrin R.

    2013-01-01

    This research is based on two studies that focus on teaching students how to integrate and assess social networking tools in marketing communications. Study 1 examines how students in marketing classes utilize social networking tools and explores their attitudes regarding the use of such tools for marketing communications. Study 2 focuses on an…

  9. 77 FR 36305 - Stream Communications Network & Media, Inc.; Order of Suspension of Trading

    Science.gov (United States)

    2012-06-18

    ... From the Federal Register Online via the Government Publishing Office SECURITIES AND EXCHANGE COMMISSION Stream Communications Network & Media, Inc.; Order of Suspension of Trading June 14, 2012. It... concerning the securities of Stream Communications Network & Media, Inc. because it has not filed...

  10. Variables of Interest in Exploring the Reflective Outcomes of Network-based Communication.

    Science.gov (United States)

    Hawkes, Mark

    2001-01-01

    Explored the opportunities presented by network-based communication to facilitate collaborative critical reflection between elementary and middle school teachers who were working on a curriculum development project. Considers self-efficacy and discusses results that showed that collaboratively produced network-based communication was significantly…

  11. The Effectiveness of Using Social Communications Networks in Mathematics Teachers' Professional Development

    Science.gov (United States)

    Hussein, Hisham Barakat

    2013-01-01

    The study aims to determine the effectiveness of using social communications networks in mathematics teachers' professional development. The main research questions was: what is the effectiveness of using social communications networks in mathematics teachers' professional development. The sub questions were: (1) what are the standards of…

  12. Intention processing in communication: a common brain network for language and gestures.

    Science.gov (United States)

    Enrici, Ivan; Adenzato, Mauro; Cappa, Stefano; Bara, Bruno G; Tettamanti, Marco

    2011-09-01

    Human communicative competence is based on the ability to process a specific class of mental states, namely, communicative intention. The present fMRI study aims to analyze whether intention processing in communication is affected by the expressive means through which a communicative intention is conveyed, that is, the linguistic or extralinguistic gestural means. Combined factorial and conjunction analyses were used to test two sets of predictions: first, that a common brain network is recruited for the comprehension of communicative intentions independently of the modality through which they are conveyed; second, that additional brain areas are specifically recruited depending on the communicative modality used, reflecting distinct sensorimotor gateways. Our results clearly showed that a common neural network is engaged in communicative intention processing independently of the modality used. This network includes the precuneus, the left and right posterior STS and TPJ, and the medial pFC. Additional brain areas outside those involved in intention processing are specifically engaged by the particular communicative modality, that is, a peri-sylvian language network for the linguistic modality and a sensorimotor network for the extralinguistic modality. Thus, common representation of communicative intention may be accessed by modality-specific gateways, which are distinct for linguistic versus extralinguistic expressive means. Taken together, our results indicate that the information acquired by different communicative modalities is equivalent from a mental processing standpoint, in particular, at the point at which the actor's communicative intention has to be reconstructed.

  13. Modeling self-organization of communication and topology in Social Networks

    Science.gov (United States)

    Sneppen, Kim

    2007-03-01

    We introduce a model of self-organization of communication and topology in social networks with a feedback between different communication habits and the topology. To study this feedback, we let agents communicate to build a perception of a network and use this information to create strategic links. We observe a narrow distribution of links when the communication is low and a system with a broad distribution of links when the communication is high. We also analyze the outcome of chatting, cheating, and lying, as strategies to get better access to information in the network. Chatting, although only adopted by a few agents, gives a global gain in the system. Contrary, in a system with too many liars a global loss is inevitable. References: M. Rosvall and K. Sneppen. ``Modeling self-organization of communication and topology in social networks.'' Phys. Rev. E 74:16108 (2006)

  14. Adaptive feedback synchronisation of complex dynamical network with discrete-time communications and delayed nodes

    Science.gov (United States)

    Wang, Tong; Ding, Yongsheng; Zhang, Lei; Hao, Kuangrong

    2016-08-01

    This paper considered the synchronisation of continuous complex dynamical networks with discrete-time communications and delayed nodes. The nodes in the dynamical networks act in the continuous manner, while the communications between nodes are discrete-time; that is, they communicate with others only at discrete time instants. The communication intervals in communication period can be uncertain and variable. By using a piecewise Lyapunov-Krasovskii function to govern the characteristics of the discrete communication instants, we investigate the adaptive feedback synchronisation and a criterion is derived to guarantee the existence of the desired controllers. The globally exponential synchronisation can be achieved by the controllers under the updating laws. Finally, two numerical examples including globally coupled network and nearest-neighbour coupled networks are presented to demonstrate the validity and effectiveness of the proposed control scheme.

  15. Immune Algorithm for Solving the Optimization Problems of Computer Communication Networks

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The basic problem in optimizing communication networks is to assign a proper circuit for each origindestination pair in networks so as to minimize the average network delay, and the network optimal route selection model is a multi-constrained 0-1 nonlinear programming problem. In this paper, a new stochastic optimization algorithm, Immune Algorithm, is applied to solve the optimization problem in communication networks. And the backbone network vBNS is chosen to illustrate the technique of evaluating delay in a virtual network. At last, IA is compared with the optimization method in communication networks based on Genetic Algorithm, and the result shows that IA is better than GA in global optimum finding.

  16. Decentralized Control of Unmanned Aerial Robots for Wireless Airborne Communication Networks

    Directory of Open Access Journals (Sweden)

    Deok-Jin Lee

    2010-09-01

    Full Text Available This paper presents a cooperative control strategy for a team of aerial robotic vehicles to establish wireless airborne communication networks between distributed heterogeneous vehicles. Each aerial robot serves as a flying mobile sensor performing a reconfigurable communication relay node which enabls communication networks with static or slow-moving nodes on gorund or ocean. For distributed optimal deployment of the aerial vehicles for communication networks, an adaptive hill-climbing type decentralized control algorithm is developed to seek out local extremum for optimal localization of the vehicles. The sensor networks estabilished by the decentralized cooperative control approach can adopt its configuraiton in response to signal strength as the function of the relative distance between the autonomous aerial robots and distributed sensor nodes in the sensed environment. Simulation studies are conducted to evaluate the effectiveness of the proposed decentralized cooperative control technique for robust communication networks.

  17. Automotive Aluminium Recycling

    Energy Technology Data Exchange (ETDEWEB)

    Gelas, B. des

    2000-07-01

    This paper aims at providing an overview on the contribution of aluminium recycling in the supply of new aluminium for automotive applications. Based on a presentation on how the global European automotive aluminium supply requirements are met, an analysis of the present and future contribution of automotive aluminium recycling is first presented. Current situation and future developments for automotive aluminium recycling practices are then commented, together with an outline on design principles for easier aluminium recycling. (orig.)

  18. Delay Analysis of Network Architectures for Machine-to-Machine Communications in LTE System

    OpenAIRE

    Shariatmadari, Hamidreza; Iraji, Sassan; Jäntti, Riku

    2014-01-01

    Machine-to-machine communications has emerged to provide autonomic communications for a wide variety of intelligentservices and applications. Among different communication technologies available for connecting machines, cellular-basedsystems have gained more attention as backhaul networks due to ubiquitous coverage and mobility support. The diverse ranges of service requirements as well as machine constraints require adopting different network architectures. This paper reviews three M2M netwo...

  19. Emergency mobile wirless networks: flyaway communications (FLAC) with WiMAX 802.16 technology

    OpenAIRE

    Donahoo, Michael; Steckler, Brian

    2005-01-01

    Wireless networks using 802.16 WiMAX technology in a "fly-away" communications (FLAC) package. Terrestrial communication networks continue to evolve very fast, with the extension offered by new IEEE 802.16 promising critical advantages benefiting civilian, government, Homeland Security, and crisis management in addition to the commercial market. A real world situation, such as the recent Tsunami in South East Asia is a good example of a complete collapse of the existing communications infr...

  20. NASA Near Earth Network (NEN) and Space Network (SN) CubeSat Communications

    Science.gov (United States)

    Schaire, Scott H.; Shaw, Harry; Altunc, Serhat; Bussey, George; Celeste, Peter; Kegege, Obadiah; Wong, Yen; Zhang, Yuwen; Patel, Chitra; Raphael, David; Burke, Jacob; Cooper, La Vida; Schier, James; Horne, William; Pierce, David

    2016-01-01

    There has been a recent trend to increase capability and drive down the Size, Weight and Power (SWAP) of satellites. NASA scientists and engineers across many of NASA's Mission Directorates and Centers are developing exciting CubeSat concepts and welcome potential partnerships for CubeSat endeavors. From a "Telemetry, Tracking and Command (TT&C) Systems and Flight Operations for Small Satellites" 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, and the potential for high numbers of operational spacecraft. The NASA Space Communications and Navigation (SCaN) Program's Near Earth Network (NEN) and Space Network (SN) are customer driven organizations that provide comprehensive communications services for space assets including data transport between a mission's orbiting satellite and its Mission Operations Center (MOC). This paper presents how well the SCaN networks, SN and NEN, are currently positioned to support the emerging small small satellite and CubeSat market as well as planned enhancements for future support.

  1. NASA Near Earth Network (NEN) and Space Network (SN) Support of CubeSat Communications

    Science.gov (United States)

    Schaire, Scott H.; Shaw, Harry C.; Altunc, Serhat; Bussey, George; Celeste, Peter; Kegege, Obadiah; Wong, Yen; Zhang, Yuwen; Patel, Chitra; Raphael, David; Burke, Jacob; Cooper, La Vida; Schier, James; Horne, William; Pierce, David

    2016-01-01

    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. 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 Telemetry, Tracking and Command (TTC) Systems and Flight Operations for Small Satellites 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, and the potential for high numbers of operational spacecraft. The NASA Space Communications and Navigation (SCaN) Programs Near Earth Network (NEN) and 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). This paper presents how well the SCaN networks, SN and NEN, are currently positioned to support the emerging small small satellite and CubeSat market as well as planned enhancements for future support.

  2. Control Based Mobile Ad Hoc Networking for survivable, dynamic, mobile Special Operation Force communications

    OpenAIRE

    Masacioglu, Mustafa.; McBride, Marlon

    2009-01-01

    Approved for public release, distribution unlimited In the next generation of wireless communication systems, there will be a need for the rapid deployment of independent mobile users. Significant examples include establishing survivable, efficient, dynamic mobile communication for tactical Special Operation Force (SOF) networks, as well as SOF units that are ad hoc networking with first responders conducting emergency/rescue and disaster relief operations. Such network scenarios cannot re...

  3. Design and performance analysis of a survivable metropolitan area fiber optic communication network

    OpenAIRE

    Angeh, Wolfgang Ondua

    1990-01-01

    The emergence of fiber optic communication technology as a viable alternative to the prevailing copper based network architectures has made it possible to capitalize on the inherent advantages of fiber which include high bandwidth,long regenerator distances and low cost. The focus of this project is to design a survivable and cost effective fiber optic communication network as a proposal for possible deployment in the city of Yaounde, Cameroon. The network comprises 100 n...

  4. UB-ANC: An Open Platform Testbed for Software-Defined Airborne Networking and Communications

    OpenAIRE

    Najafabadi, SayedJalil Modares; Mastronarde, Nicholas; Medley, Michael J.; Matyjas, John D.

    2015-01-01

    We present the University at Buffalo's Software-Defined Airborne Networking and Communications Testbed (UB-ANC). UB-ANC is an open software/hardware platform that aims to facilitate rapid testing and repeatable comparative evaluation of various airborne networking and communications protocols at different layers of the network protocol stack. In particular, it combines quadcopters capable of autonomous flight with USRP E310 embedded software-defined radios (SDRs), which enable flexible deploy...

  5. Space Link Extension (SLE) Emulation for High-Throughput Network Communication

    Science.gov (United States)

    Murawski, Robert W.; Tchorowski, Nicole; Golden, Bert

    2014-01-01

    As the data rate requirements for space communications increases, significant stress is placed not only on the wireless satellite communication links, but also on the ground networks which forward data from end-users to remote ground stations. These wide area network (WAN) connections add delay and jitter to the end-to-end satellite communication link, effects which can have significant impacts on the wireless communication link. It is imperative that any ground communication protocol can react to these effects such that the ground network does not become a bottleneck in the communication path to the satellite. In this paper, we present our SCENIC Emulation Lab testbed which was developed to test the CCSDS SLE protocol implementations proposed for use on future NASA communication networks. Our results show that in the presence of realistic levels of network delay, high-throughput SLE communication links can experience significant data rate throttling. Based on our observations, we present some insight into why this data throttling happens, and trace the probable issue back to non-optimal blocking communication which is sup-ported by the CCSDS SLE API recommended practices. These issues were presented as well to the SLE implementation developers which, based on our reports, developed a new release for SLE which we show fixes the SLE blocking issue and greatly improves the protocol throughput. In this paper, we also discuss future developments for our end-to-end emulation lab and how these improvements can be used to develop and test future space communication technologies.

  6. Network coding based joint signaling and dynamic bandwidth allocation scheme for inter optical network unit communication in passive optical networks

    Science.gov (United States)

    Wei, Pei; Gu, Rentao; Ji, Yuefeng

    2014-06-01

    As an innovative and promising technology, network coding has been introduced to passive optical networks (PON) in recent years to support inter optical network unit (ONU) communication, yet the signaling process and dynamic bandwidth allocation (DBA) in PON with network coding (NC-PON) still need further study. Thus, we propose a joint signaling and DBA scheme for efficiently supporting differentiated services of inter ONU communication in NC-PON. In the proposed joint scheme, the signaling process lays the foundation to fulfill network coding in PON, and it can not only avoid the potential threat to downstream security in previous schemes but also be suitable for the proposed hybrid dynamic bandwidth allocation (HDBA) scheme. In HDBA, a DBA cycle is divided into two sub-cycles for applying different coding, scheduling and bandwidth allocation strategies to differentiated classes of services. Besides, as network traffic load varies, the entire upstream transmission window for all REPORT messages slides accordingly, leaving the transmission time of one or two sub-cycles to overlap with the bandwidth allocation calculation time at the optical line terminal (the OLT), so that the upstream idle time can be efficiently eliminated. Performance evaluation results validate that compared with the existing two DBA algorithms deployed in NC-PON, HDBA demonstrates the best quality of service (QoS) support in terms of delay for all classes of services, especially guarantees the end-to-end delay bound of high class services. Specifically, HDBA can eliminate queuing delay and scheduling delay of high class services, reduce those of lower class services by at least 20%, and reduce the average end-to-end delay of all services over 50%. Moreover, HDBA also achieves the maximum delay fairness between coded and uncoded lower class services, and medium delay fairness for high class services.

  7. Scholarly communication in networked environment: problems and prospects

    OpenAIRE

    Vimal Kumar, V.

    2007-01-01

    This article gives an overview of how popularity of World Wide Web and open access concepts challenge the existence of traditional scholarly communication. New publishing outlets such as blogs, wiki and podcasting facilitate agile communication channels for scholarly communication. Open access concepts in scholarly communication enable free access of knowledge. Research community and information professionals hope that scholarly communication through Internet makes available wider access of k...

  8. Time as a limited resource: Communication Strategy in Mobile Phone Networks

    CERN Document Server

    Miritello, Giovanna; Lara, Rubén; Martínez-López, Rocío; Roberts, Sam G B; Dunbar, Robin I M

    2013-01-01

    We used a large database of 9 billion calls from 20 million mobile users to examine the relationships between aggregated time spent on the phone, personal network size, tie strength and the way in which users distributed their limited time across their network (disparity). Compared to those with smaller networks, those with large networks did not devote proportionally more time to communication and had on average weaker ties (as measured by time spent communicating). Further, there were not substantially different levels of disparity between individuals, in that mobile users tend to distribute their time very unevenly across their network, with a large proportion of calls going to a small number of individuals. Together, these results suggest that there are time constraints which limit tie strength in large personal networks, and that even high levels of mobile communication do not fundamentally alter the disparity of time allocation across networks.

  9. On improving communication in emergency response at network and organizational levels

    OpenAIRE

    Dilmaghani, Raheleh B.

    2010-01-01

    The scale and frequency of large-scale disasters and the wide range of severities and the myriad ways a nation has been affected by, reveals the importance of a reliable communication system in emergency response scenarios. Communication may fail for a broken network component, infrastructure failure, or unreachability. A variety of communication technologies have been deployed at crisis sites but the problems of interoperability, unreachability, unclear communication plan and resource alloca...

  10. Learning to Communicate to Solve Riddles with Deep Distributed Recurrent Q-Networks

    OpenAIRE

    Foerster, Jakob N.; Assael, Yannis M.; de Freitas, Nando; Whiteson, Shimon

    2016-01-01

    We propose deep distributed recurrent Q-networks (DDRQN), which enable teams of agents to learn to solve communication-based coordination tasks. In these tasks, the agents are not given any pre-designed communication protocol. Therefore, in order to successfully communicate, they must first automatically develop and agree upon their own communication protocol. We present empirical results on two multi-agent learning problems based on well-known riddles, demonstrating that DDRQN can successful...

  11. Security in Infrastructure-less and Decentralized Communication Networks : Location-based Intrusion Response and User-based Cooperative Decisions

    OpenAIRE

    König, André

    2011-01-01

    Infrastructure-less communication substrates like multi-hop wireless mobile ad hoc networks in combination with applications based on decentralized networks like peer-to-peer networks facilitate establishing digital communication services in a spontaneous way. Envisioned application scenarios include, for example, enabling communication in large-scale disaster scenarios. Here, a preexisting communication infrastructure might not be available. Thus, devices have to act both as communication en...

  12. Transformation of Traditional Marketing Communications in to Paradigms of Social Media Networking

    CERN Document Server

    Nair, T R Gopalakrishnan

    2012-01-01

    Effective Communication for marketing is a vital field in business organizations, which is used to convey the details about their products and services to the market segments and subsequently to build long lasting customer relationships. This paper focuses on an emerging component of the integrated marketing communication, ie. social media networking, as it is increasingly becoming the trend. In 21st century, the marketing communication platforms show a tendency to shift towards innovative technology bound people networking which is becoming an acceptable domain of interaction. Though the traditional channels like TV, print media etc. are still active and prominent in marketing communication, the presences of the Internet and more specifically the Social Media Networking, has started influencing the way individuals and business enterprises communicate. It has become evident that more individuals and business enterprises are engaging the social media networking sites either to accelerate the sales of their pro...

  13. Social Networking: Changing the way we communicate and do business.

    OpenAIRE

    Jones, Kevin

    2009-01-01

    This paper reviews the value of social networking and the impact it can have on small and large businesses. The paper also reviews the Social Networking Business Plan and the power of recommender networks. Examples are given of inbound and outbound marketing techniques. Social Networking is an integral part of inbound marketing. A synopsis of the evolving demographic of social networkers is presented to add clarity and show potential for social networking websites and tools.

  14. Development of Network Devices Supporting Communication Independence In NPP I and C Systems

    International Nuclear Information System (INIS)

    As advanced digital I and C systems of nuclear power plants or research reactors are being introduced to replace analog systems, a data communication network is necessary for data exchanges between I and C systems of nuclear power plants or research reactors. Data communication network technology may have significant impact on I and C systems. As the safety I and C system is composed of redundant channels to enhance the performance of the safety functions and data communication system is used to transmit the data generated by the digital I and C systems, communication independence is required to mitigate the risk of safety I and C system failure. Therefore this paper mainly discusses the issues related to the communication independence and the current status of network devices we designed, developed, and validated to satisfy the requirements of function, performance, and communication independence. (authors)

  15. Implementability of two-qubit unitary operations over the butterfly network and the ladder network with free classical communication

    Energy Technology Data Exchange (ETDEWEB)

    Akibue, Seiseki [Department of Physics, Graduate School of Science, The University of Tokyo, Tokyo (Japan); Murao, Mio [Department of Physics, Graduate School of Science, The University of Tokyo, Tokyo, Japan and NanoQuine, The University of Tokyo, Tokyo (Japan)

    2014-12-04

    We investigate distributed implementation of two-qubit unitary operations over two primitive networks, the butterfly network and the ladder network, as a first step to apply network coding for quantum computation. By classifying two-qubit unitary operations in terms of the Kraus-Cirac number, the number of non-zero parameters describing the global part of two-qubit unitary operations, we analyze which class of two-qubit unitary operations is implementable over these networks with free classical communication. For the butterfly network, we show that two classes of two-qubit unitary operations, which contain all Clifford, controlled-unitary and matchgate operations, are implementable over the network. For the ladder network, we show that two-qubit unitary operations are implementable over the network if and only if their Kraus-Cirac number do not exceed the number of the bridges of the ladder.

  16. Future Unified Communication Based on Ubiquitous Hierarchical Generalized-Sensor Network Architecture

    Directory of Open Access Journals (Sweden)

    Zhitong Huang

    2012-03-01

    Full Text Available Recent advances in wireless sensor network (WSN and radio frequency identifier (RFID have made it possible to extend current human-to-human communication to the future unified communication environment among human society, computer network and the external physical world. A ubiquitous hierarchical generalized-sensor network (UHGSN is presented in this paper as a typical network model for such unified communication architecture. The sensor information processing unit and the hierarchical distributed agent server are introduced as the basic network elements in this architecture for effective information communication, and the topology, addressing and recovery problems are analyzed. As the basic applications, the combined “key word” based characterized searching mechanism and the performance monitoring processes are discussed, along with the corresponding protocol message definition and encoding format. Simulation results show the advancements of the presented hierarchical architecture and the job-list based characterized searching mechanism.

  17. Adaptive autonomous Communications Routing Optimizer for Network Efficiency Management Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Maximizing network efficiency for NASA's Space Networking resources is a large, complex, distributed problem, requiring substantial collaboration. We propose the...

  18. PROFESSIONAL ADAPTATION AS A MECHANISM FOR SOCIO- NETWORK SECURITY OF THE PERSON IN THE NETWORK COMMUNICATION SPACE

    Directory of Open Access Journals (Sweden)

    Lubov Muhamedovna Mkrtchyan

    2015-01-01

    Full Text Available The development of a network communicative space causes the transformation of labor and actualizes the problem of employment as the main indicator of social security. In this regard, the article considers one of the mechanisms ensuring social security of the person as the cultural development of society and the ability to create and maintain a system of values and professional orientations of the person - effective professional adaptation, requirements to which are largely determined by the ability to manage information network technologies, professional and informational culture, the ability to self-education. In its turn, social security in modern conditions acquires the features of socio-network security as a stable state of human security and protection from the negative effects of network communications, which can modify the behavior of a person, his values, and professional orientations and mislead him in the information space. Therefore, this article analyzes the relationship of professional adaptation and professional culture which in the context of network communication is determined by specific activities of the network professional communities, propagating certain values and behaviors. The level of information culture requires from individuals not only systematic knowledge and skills in information technology, but also the ability to think critically, to provide appropriate selection of information, to oppose network risks and threats, to use the communication network as an adaptive resource in the process of self-education.

  19. An analysis of communications and networking technologies for the smart grid

    Energy Technology Data Exchange (ETDEWEB)

    Garcia Hernandez, Joaquin [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico)

    2013-03-01

    The Smart Grid concept has been foreseen as the integration of the electrical generation, transmission and distribution network and the data communications network. Although, traditional communications interfaces, protocols and standards has been used in the electrical grid in an isolated manner, modern communications network is considered as the fundamental enabling technology within the future Smart Grid. Modern communications technologies, protocol architectures and standards can help to build a common communications network infrastructure for data transport between customer premises, power substations, and power distribution systems, utility control centers and utility data centers. The Smart Grid will support traditional applications such as SCADA, distribution automation (DA), energy management systems (EMS), demand site management (DSM) and automatic meter reading (AMR), etc., as well as new applications like advanced metering infrastructure (AMI), substation automation (SA), microgrids, distributed generation, grid monitoring and control, data storage and analysis, among others. To make this possible, the Smart Grid requires a two-way wide area communications network between different dispersed areas, from generation, to distribution to consumer premises. In fact, it will consist of many different types of communications networks such as wide area networks, local area network, home area networks, etc. This requires a new architectural approach to implement a common communications infrastructure that provides the reliability, scalability, security and interoperability to support multiple applications. In addition, open standards addressing interoperability, are key for the development and deployment of the Smart Grid as a true integrated network. A communications backbone is necessary to provide interoperability. To achieve the level of networking, interoperability and security that meets the technical requirements of the Smart Grid, its data communications

  20. ENERGY-EFFICIENT SENSING COVERAGE AND COMMUNICATION FOR WIRELESS SENSOR NETWORKS

    Institute of Scientific and Technical Information of China (English)

    Xi CHEN; Qianchuan ZHAO; Xiaohong GUAN

    2007-01-01

    Wireless sensor networks have a wide range of applications. Sensing coverage and communication coverage are two fundamental quality of service. In this paper, we present our work on energy efficient sensing coverage and communication. We design several schemes for sensing coverage subject to different requirements and constraints respectively. We also propose a broadcasting communication protocol with high energy efficiency and low latency for large scale sensor networks based on the Small World network theory. Simulation and experiment results show that our schemes and protocol have good performance.

  1. Simulation technologies in networking and communications selecting the best tool for the test

    CERN Document Server

    Pathan, Al-Sakib Khan; Khan, Shafiullah

    2014-01-01

    Simulation is a widely used mechanism for validating the theoretical models of networking and communication systems. Although the claims made based on simulations are considered to be reliable, how reliable they really are is best determined with real-world implementation trials.Simulation Technologies in Networking and Communications: Selecting the Best Tool for the Test addresses the spectrum of issues regarding the different mechanisms related to simulation technologies in networking and communications fields. Focusing on the practice of simulation testing instead of the theory, it presents

  2. Cooperative device-to-device communication in cognitive radio cellular networks

    CERN Document Server

    Li, Peng

    2014-01-01

    This brief examines current research on cooperative device-to-device (D2D) communication as an enhanced offloading technology to improve the performance of cognitive radio cellular networks. By providing an extensive review of recent advances in D2D communication, the authors demonstrate that the quality of D2D links significantly affects offloading performance in cellular networks, which motivates the design of cooperative D2D communication. After presenting the architecture of cooperative D2D communication, the challenges of capacity maximization and energy efficiency are addressed by optimi

  3. Social Networking, The "Third Place," and The Evolution of Communication

    Science.gov (United States)

    New Media Consortium, 2007

    2007-01-01

    The purpose of this white paper is to put forth a proposition that technology has not only mediated communication in numerous ways, but that the ways we communicate, including the ways we talk and think about communication, are changing as a result. Mediated by new tools and new technologies that have made the marginal cost of long distance…

  4. Using satellite communications for a mobile computer network

    Science.gov (United States)

    Wyman, Douglas J.

    1993-01-01

    The topics discussed include the following: patrol car automation, mobile computer network, network requirements, network design overview, MCN mobile network software, MCN hub operation, mobile satellite software, hub satellite software, the benefits of patrol car automation, the benefits of satellite mobile computing, and national law enforcement satellite.

  5. NASA Near Earth Network (NEN), Deep Space Network (DSN) and Space Network (SN) Support of CubeSat Communications

    Science.gov (United States)

    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

  6. Empirical study of the role of the topology in spreading on communication networks

    OpenAIRE

    Medvedev, Alexey N.; Kertesz, Janos

    2016-01-01

    Topological aspects, like community structure, and temporal activity patterns, like burstiness, have been shown to severly influence the speed of spreading in temporal networks. We study the influence of the topology on the susceptible-infected (SI) spreading on time stamped communication networks, as obtained from a dataset of mobile phone records. We consider city level networks with intra- and inter-city connections. The networks using only intra-city links are usually sparse, where the sp...

  7. High-Speed Optical Wide-Area Data-Communication Network

    Science.gov (United States)

    Monacos, Steve P.

    1994-01-01

    Proposed fiber-optic wide-area network (WAN) for digital communication balances input and output flows of data with its internal capacity by routing traffic via dynamically interconnected routing planes. Data transmitted optically through network by wavelength-division multiplexing in synchronous or asynchronous packets. WAN implemented with currently available technology. Network is multiple-ring cyclic shuffle exchange network ensuring traffic reaches its destination with minimum number of hops.

  8. Characterizing Social Networks and Communication Channels in a Web-Based Peer Support Intervention.

    Science.gov (United States)

    Owen, Jason E; Curran, Michaela; Bantum, Erin O'Carroll; Hanneman, Robert

    2016-06-01

    Web and mobile (mHealth) interventions have promise for improving health outcomes, but engagement and attrition may be reducing effect sizes. Because social networks can improve engagement, which is a key mechanism of action, understanding the structure and potential impact of social networks could be key to improving mHealth effects. This study (a) evaluates social network characteristics of four distinct communication channels (discussion board, chat, e-mail, and blog) in a large social networking intervention, (b) predicts membership in online communities, and (c) evaluates whether community membership impacts engagement. Participants were 299 cancer survivors with significant distress using the 12-week health-space.net intervention. Social networking attributes (e.g., density and clustering) were identified separately for each type of network communication (i.e., discussion board, blog, web mail, and chat). Each channel demonstrated high levels of clustering, and being a community member in one communication channel was associated with being in the same community in each of the other channels (φ = 0.56-0.89, ps communication channels, suggesting that each channel reached distinct types of users. Finally, membership in a discussion board, chat, or blog community was strongly associated with time spent engaging with coping skills exercises (Ds = 1.08-1.84, ps communication allow participants to expand the number of individuals with whom they are communicating, create opportunities for communicating with different individuals in distinct channels, and likely enhance overall engagement.

  9. Second language social networks and communication-related acculturative stress: The role of interconnectedness

    Directory of Open Access Journals (Sweden)

    Marina M Doucerain

    2015-08-01

    Full Text Available Although a substantial amount of cross-cultural psychology research has investigated acculturative stress in general, little attention has been devoted specifically to communication-related acculturative stress. In line with the view that cross-cultural adaptation and second language (L2 learning are social and interpersonal phenomena, the present study examines the hypothesis that migrants' L2 social network size and interconnectedness predict communication-related acculturative stress. The main idea underlying this hypothesis is that L2 social networks play an important role in fostering social and cultural aspects of communicative competence. Specifically, higher interconnectedness may reflect greater access to unmodified natural cultural representations and L2 communication practices, thus fostering communicative competence through observational learning. As such, structural aspects of migrants' L2 social networks may be protective against acculturative stress arising from chronic communication difficulties. Results from a study of first generation migrant students (N=100 support this idea by showing that both inclusiveness and density of the participants' L2 network account for unique variance in communication-related acculturative stress but not in general acculturative stress. These results support the idea that research on cross-cultural adaptation would benefit from disentangling the various facets of acculturative stress and that the structure of migrants' L2 network matters for language related outcomes. Finally, this study contributes to an emerging body of work that attempts to integrate cultural/cross-cultural research on acculturation and research on intercultural communication and second language learning.

  10. Storage Area Network Implementation on an Educational Institute Network Computer Networking and Communication

    CERN Document Server

    Osama, Safarini

    2011-01-01

    the storage infrastructure is the foundation on which information relies and therefore must support a company's business objectives and business model. In this environment, simply deploying more and faster storage devices is not enough; a new kind of infrastructure is needed, one that provides more enhanced network availability, data accessibility, and system manageability than is provided by today's infrastructure. The SAN meets this challenge. The SAN liberates the storage device, so it is not on a particular server bus, and attaches it directly to the network. In other words, storage is externalized and functionally distributed across the organization. The SAN also enables the centralizing of storage devices and the clustering of servers, which makes for easier and less expensive administration. So the idea is to create an intelligent SAN infrastructure that stretches to meet increased demands, allows highly available and heterogeneous access to expanding information.

  11. EVOLUTION OF WIRELESS MOBILE COMMUNICATION NETWORKS AND FUTURE OF CELLULAR MARKET IN INDIA

    Directory of Open Access Journals (Sweden)

    Arjun Kondur

    2012-10-01

    Full Text Available In this paper, we discuss the evolution of the mobile communication systems from GSM to LTE (2G to 4G and the trends in the mobile communication industry. The Global System for Mobile Communication (GSM is a well established cellular system targeted here due to its engineering success and the large number of users currently using the services. The flexibility of wireless networks over voice and data transmission makes it one of the most popular modes of communication. Evolution to next generation services depends on an addition of new services and new features to the existing networks or even an integration of different communication technologies. With the invention of the devices such as tablets and smart phones the need to improve the data transmission rates and transmission efficiency has increased to higher than ever before. In this paper, we focus at some of the important issues pertaining to the evolution of mobile communication networks and predict the future of the networks based on the analysis of the cellular market in India. Since GSM networks accounts for more than 75% of the world wide cellular network, only the evolution of GSM network has been discussed in this paper.

  12. Statistically validated mobile communication networks: the evolution of motifs in European and Chinese data

    Science.gov (United States)

    Li, Ming-Xia; Palchykov, Vasyl; Jiang, Zhi-Qiang; Kaski, Kimmo; Kertész, János; Miccichè, Salvatore; Tumminello, Michele; Zhou, Wei-Xing; Mantegna, Rosario N.

    2014-08-01

    Big data open up unprecedented opportunities for investigating complex systems, including society. In particular, communication data serve as major sources for computational social sciences, but they have to be cleaned and filtered as they may contain spurious information due to recording errors as well as interactions, like commercial and marketing activities, not directly related to the social network. The network constructed from communication data can only be considered as a proxy for the network of social relationships. Here we apply a systematic method, based on multiple-hypothesis testing, to statistically validate the links and then construct the corresponding Bonferroni network, generalized to the directed case. We study two large datasets of mobile phone records, one from Europe and the other from China. For both datasets we compare the raw data networks with the corresponding Bonferroni networks and point out significant differences in the structures and in the basic network measures. We show evidence that the Bonferroni network provides a better proxy for the network of social interactions than the original one. Using the filtered networks, we investigated the statistics and temporal evolution of small directed 3-motifs and concluded that closed communication triads have a formation time scale, which is quite fast and typically intraday. We also find that open communication triads preferentially evolve into other open triads with a higher fraction of reciprocated calls. These stylized facts were observed for both datasets.

  13. Statistically validated mobile communication networks: the evolution of motifs in European and Chinese data

    International Nuclear Information System (INIS)

    Big data open up unprecedented opportunities for investigating complex systems, including society. In particular, communication data serve as major sources for computational social sciences, but they have to be cleaned and filtered as they may contain spurious information due to recording errors as well as interactions, like commercial and marketing activities, not directly related to the social network. The network constructed from communication data can only be considered as a proxy for the network of social relationships. Here we apply a systematic method, based on multiple-hypothesis testing, to statistically validate the links and then construct the corresponding Bonferroni network, generalized to the directed case. We study two large datasets of mobile phone records, one from Europe and the other from China. For both datasets we compare the raw data networks with the corresponding Bonferroni networks and point out significant differences in the structures and in the basic network measures. We show evidence that the Bonferroni network provides a better proxy for the network of social interactions than the original one. Using the filtered networks, we investigated the statistics and temporal evolution of small directed 3-motifs and concluded that closed communication triads have a formation time scale, which is quite fast and typically intraday. We also find that open communication triads preferentially evolve into other open triads with a higher fraction of reciprocated calls. These stylized facts were observed for both datasets. (paper)

  14. Research on the Architecture of a Basic Reconfigurable Information Communication Network

    Directory of Open Access Journals (Sweden)

    Ruimin Wang

    2013-01-01

    Full Text Available The current information network cannot fundamentally meet some urgent requirements, such as providing ubiquitous information services and various types of heterogeneous network, supporting diverse and comprehensive network services, possessing high quality communication effects, ensuring the security and credibility of information interaction, and implementing effective supervisory control. This paper provides the theory system for the basic reconfigurable information communication network based on the analysis of present problems on the Internet and summarizes the root of these problems. It also provides an in-depth discussion about the related technologies and the prime components of the architecture.

  15. Network Communication Reliability Analysis in Terms of Fault Tree

    Directory of Open Access Journals (Sweden)

    FITIGAU Ioan

    2015-05-01

    Full Text Available In this paper we studied and analyzed a network structure in terms of fault tree. We developed a fault tree based on the network structure to analyze all admissible states of emergency that can lead to non-functioning of the entire network. We studied the damage to the network in terms of primary events that may lead to its malfunction namely: damage to the network links, damage to the routers and damage in the routing protocols functioning. For each scenario possible fault in the network have made minimal cut sets whose appearance will lead to network failure. Also, through the results obtained from monitoring a telecommunications service provider over two years, we watched the likelihood of damage to the analyzed network and finally we discussed the possibilities of preventing damage to the network through optimizations applicable on the links, routing equipment and over the routing protocols.

  16. Automotic Recognition of Sleep Spindles Based on Two-Stage Classifier with Artificial Neural Networks and Support Vector Machines

    Directory of Open Access Journals (Sweden)

    MohammadHoseyn Khaksar

    2008-03-01

    Full Text Available Sleep spindles are one of the most important transient waveforms found in the sleep EEG signal. Here, we introduce a two-stage procedure based on artificial neural networks for the automatic recognition of sleep spindles (SS in a 19-channel electroencephalographic signal. In the first stage, a pre-processing perception is used for enhancing overall detection and also reducing computation time. In the second stage, the selected Sleep spindles (SS, classified with neural network post-classifier. Classifying tools in post-processing procedure were MLP and RBSVM that their operations are compared in the last section of the report. Visual inspection of 19-channel EEG from six subjects by one expert in this theme, showed that RBSVM operation is better than MLP with BP (Back propagation training, that SVM provided 91.4% average sensitivity and 3.85% average false detection rate.

  17. Communication efficiency and congestion of signal traffic in large-scale brain networks.

    Science.gov (United States)

    Mišić, 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.

  18. Proceedings of the Workshop on Advanced Network and Technology Concepts for Mobile, Micro, and Personal Communications

    Science.gov (United States)

    Paul, Lori (Editor)

    1991-01-01

    The Workshop on Advanced Network and Technology Concepts for Mobile, Micro, and Personal Communications was held at NASA's JPL Laboratory on 30-31 May 1991. It provided a forum for reviewing the development of advanced network and technology concepts for turn-of-the-century telecommunications. The workshop was organized into three main categories: (1) Satellite-Based Networks (L-band, C-band, Ku-band, and Ka-band); (2) Terrestrial-Based Networks (cellular, CT2, PCN, GSM, and other networks); and (3) Hybrid Satellite/Terrestrial Networks. The proceedings contain presentation papers from each of the above categories.

  19. Coping with the Upcoming Heterogeneity in 5G Communications and Storage Using Fulcrum Network Codes

    DEFF Research Database (Denmark)

    Roetter, Daniel Enrique Lucani; Pedersen, Morten Videbæk; Heide, Janus;

    2014-01-01

    In this paper, Fulcrum network codes are introduced as a viable solution to cope with the heterogeneity of 5G communication and storage systems. Fulcrum network codes are an enhancement of random linear network codes (RLNC) offering high throughput performance at low overhead. This contrasts...... that a system using Fulcrum network codes will be able to perform a fluid allocation of complexity. We introduce the basic concept of Fulcrum network codes as well as a performance evaluation for basic network topologies demonstrating the abilities and potential of this new class of codes....

  20. Information and knowledge flows in product development of automotive industry – a comparison between formal and informal networks

    Directory of Open Access Journals (Sweden)

    Renelson Ribeiro Sampaio

    2013-03-01

    Full Text Available To maintain competitive advantage, companies must innovate. Thus, high quality, low cost and diversity of products became the starting condition for competitiveness. As a result, speed and flexibility in the design of new products are crucial, as these factors are related to the ability of companies to respond adequately to the pressures from the market. Innovation is usually related to the introduction of something new in a particular work process, which lead to new products or services. The ability for people to share information is then to be seen as a factor of strengthening of the work processes in order to contribute substantially to the company's competitive advantage in this new context. Considering these aspects, this paper seeks to map the processes of product development for an automobile company, analyzing and mapping the flow of information. The main contribution of this study is the critical analysis of social network established in a time of development of a project. This analysis provides an estimate of the level of diffusion of information and knowledge among team members, as well as the comparison between social networking and formal network mapped empirically defined a priori in the company's written procedures.

  1. Modeling self-organization of communication and topology in social networks

    CERN Document Server

    Rosvall, M

    2006-01-01

    This paper introduces a model of self-organization between communication and topology in social networks, with a feedback between different communication habits and the topology. To study this feedback, we let agents communicate to build a perception of a network and use this information to create strategic links. We observe a narrow distribution of links when the communication is low and a system with a broad distribution of links when the communication is high. We also analyze the outcome of chatting, cheating, and lying, as strategies to get better access to information in the network. Chatting, although only adopted by a few agents, gives a global gain in the system. Contrary, a global loss is inevitable in a system with too many liars

  2. Communication, opponents, and clan performance in online games: a social network approach.

    Science.gov (United States)

    Lee, Hong Joo; Choi, Jaewon; Kim, Jong Woo; Park, Sung Joo; Gloor, Peter

    2013-12-01

    Online gamers form clans voluntarily to play together and to discuss their real and virtual lives. Although these clans have diverse goals, they seek to increase their rank in the game community by winning more battles. Communications among clan members and battles with other clans may influence the performance of a clan. In this study, we compared the effects of communication structure inside a clan, and battle networks among clans, with the performance of the clans. We collected battle histories, posts, and comments on clan pages from a Korean online game, and measured social network indices for communication and battle networks. Communication structures in terms of density and group degree centralization index had no significant association with clan performance. However, the centrality of clans in the battle network was positively related to the performance of the clan. If a clan had many battle opponents, the performance of the clan improved.

  3. Robust, Multi-layered Plan Execution and Revision for Operation of a Network of Communication Antennas

    Science.gov (United States)

    Chien, S. A.; Hill, R. W., Jr.; Govindjee, A.; Wang, X.; Estlin, T.; Griesel, M. A.; Lam, R.; Fayyad, K. V.

    1996-01-01

    This paper describes a hierarchical scheduling, planning, control, and execution monitoring architecture for automating operations of a worldwide network of communications antennas. The purpose of this paper is to describe an architecture for automating the process of capturing spacecraft data.

  4. Potentials and Limitations of CDMA Networks for Combined Inter-Satellite Communication and Relative Navigation

    NARCIS (Netherlands)

    Sun, R.; Guo, J.; Gill, E.K.A.; Maessen, D.C.

    2012-01-01

    Precision formation flying missions require formation acquisition and maintenance through the interactions among spacecraft by the inter-satellite communication and relative navigation. This paper analyses the dedicated system constraints of the network architecture for precision formation flying mi

  5. Characterizing Network Architecture for Inter-satellite Communication and Relative Navigation in Precise Formation Flying

    NARCIS (Netherlands)

    Sun, R.; Guo, J.; Gill, E.K.A.; Maessen, D.

    2011-01-01

    Precise formation flying (PFF) missions require formation acquisition and maintenance through interactions among spacecraft by inter-satellite communication and relative navigation. That requires the network architecture to satisfy dedicated system constraints of time-criticality for updating naviga

  6. FY 1999 Blue Book: Computing, Information, and Communications: Networked Computing for the 21st Century

    Data.gov (United States)

    Networking and Information Technology Research and Development, Executive Office of the President — U.S.research and development R and D in computing, communications, and information technologies has enabled unprecedented scientific and engineering advances,...

  7. In-House Communication Support System Based on the Information Propagation Model Utilizes Social Network

    Science.gov (United States)

    Takeuchi, Susumu; Teranishi, Yuuichi; Harumoto, Kaname; Shimojo, Shinji

    Almost all companies are now utilizing computer networks to support speedier and more effective in-house information-sharing and communication. However, existing systems are designed to support communications only within the same department. Therefore, in our research, we propose an in-house communication support system which is based on the “Information Propagation Model (IPM).” The IPM is proposed to realize word-of-mouth communication in a social network, and to support information-sharing on the network. By applying the system in a real company, we found that information could be exchanged between different and unrelated departments, and such exchanges of information could help to build new relationships between the users who are apart on the social network.

  8. Statistically validated mobile communication networks: Evolution of motifs in European and Chinese data

    CERN Document Server

    Li, Ming-Xia; Jiang, Zhi-Qiang; Kaski, Kimmo; Kertész, Janos; Miccichè, Salvatore; Tumminello, Michele; Zhou, Wei-Xing; Mantegna, Rosario N

    2014-01-01

    Big data open up unprecedented opportunities to investigate complex systems including the society. In particular, communication data serve as major sources for computational social sciences but they have to be cleaned and filtered as they may contain spurious information due to recording errors as well as interactions, like commercial and marketing activities, not directly related to the social network. The network constructed from communication data can only be considered as a proxy for the network of social relationships. Here we apply a systematic method, based on multiple hypothesis testing, to statistically validate the links and then construct the corresponding Bonferroni network, generalized to the directed case. We study two large datasets of mobile phone records, one from Europe and the other from China. For both datasets we compare the raw data networks with the corresponding Bonferroni networks and point out significant differences in the structures and in the basic network measures. We show eviden...

  9. New Structural Forms In Multinationals: Decentralization At The Expense Of Personal Communication Networks?

    OpenAIRE

    Marschan, R

    1994-01-01

    Recent literature on decentralized power structures within multinationals suggests that these structures encourage the development of personal and horizontal communication networks. Based on an in-depth case study on twelve units of one Finnish multinational the findings show that the decentralization process enhanced personal communication networks among top managers, while middle management and operating employees perceived limited opportunities to extend their personal contacts with other ...

  10. Reach on Policy-based Transmition Control Technology in MPLS Communication Network

    OpenAIRE

    Jingyang Wang; Yu Hua; Min Huang; Liwei Guo; Wanzhen Zhou

    2012-01-01

    With the increasing variety of service types supported by the communication network, more and more requirements for bandwidth occurred. Different types of services have different characteristics in the aspects of importance, bandwidth demand, time-sensitive and so on. Customers’s requirements for the controllability and manageability of communication network are more and more demanding. The paper researches on policy-based transmition control technology in MPLS controllable and manageab...

  11. New horizons in mobile and wireless communications, v.4 ad hoc networks and pans

    CERN Document Server

    Prasad, Ramjee

    2009-01-01

    Based on cutting-edge research projects in the field, this book (part of a comprehensive 4-volume series) provides the latest details and covers the most impactful aspects of mobile, wireless, and broadband communications development. These books present key systems and enabling technologies in a clear and accessible manner, offering you a detailed roadmap the future evolution of next generation communications. Other volumes cover Networks, Services and Applications; Reconfigurability; and Ad Hoc Networks.

  12. Social Networking Among Youth and Their Communication and Conflict Resolution Skills

    OpenAIRE

    Mistry DR; Verma M; Vyas SN; Kantharia SL

    2014-01-01

    Introduction: New digital media have dramatically altered the communication landscape, especially for youth. “Indian web users spend 26 minutes online each day”. This study is concerned with effect of social networking on youth regarding potential risk, safety, wellbeing & skill development because they are still maturing & forming the ability to attain & implement communication & conflict resolution skill on interpersonal level. Aim & objective: To explore the impact of social networking on ...

  13. New horizons in mobile and wireless communications, v.2 networks, services and applications

    CERN Document Server

    Prasad, Ramjee

    2009-01-01

    Based on cutting-edge research projects in the field, this book (part of a comprehensive 4-volume series) provides the latest details and covers the most impactful aspects of mobile, wireless, and broadband communications development. These books present key systems and enabling technologies in a clear and accessible manner, offering you a detailed roadmap the future evolution of next generation communications. Other volumes cover Networks, Services and Applications; Reconfigurability; and Ad Hoc Networks.

  14. aDTN - Undetectable Communication in Wireless Delay-tolerant Networks (Working Draft)

    OpenAIRE

    Barroso, Ana

    2015-01-01

    This document describes a best-effort delay-tolerant communication system that protects the privacy of users in wireless ad-hoc networks by making their communication undetectable. The proposed system is a wireless broadcast-based adaptation of mix networks where each user belongs to at least one group it trusts, and each group acts as a mix node. Assuming encryption is not broken, it provides undetectability of all users and messages against external adversaries, as well as undetectability o...

  15. The Effect of Communication Topology on Scalar Field Estimation by Networked Robotic Swarms

    OpenAIRE

    Ramachandran, Ragesh K; Berman, Spring

    2016-01-01

    This paper studies the problem of reconstructing a two-dimensional scalar field using a swarm of networked robots with local communication capabilities. We consider the communication network of the robots to form either a chain or a grid topology. We formulate the reconstruction problem as an optimization problem that is constrained by first-order linear dynamics on a large, interconnected system. To solve this problem, we employ an optimization-based scheme that uses a gradient-based method ...

  16. Asynchronous Free-Space Optical CDMA Communications System for Last-mile Access Network

    DEFF Research Database (Denmark)

    Jurado-Navas, Antonio; Raddo, Thiago R.; Sanches, Anderson L.;

    2016-01-01

    We propose a new hybrid asynchronous OCDMA-FSO communications system for access network solutions. New ABER expressions are derived under gamma-gamma scintillation channels, where all users can surprisingly achieve error-free transmissions when FEC is employed.......We propose a new hybrid asynchronous OCDMA-FSO communications system for access network solutions. New ABER expressions are derived under gamma-gamma scintillation channels, where all users can surprisingly achieve error-free transmissions when FEC is employed....

  17. Design and Implementation of Network Communication Interface Based on μCLinux

    Institute of Scientific and Technical Information of China (English)

    LV Jie; WANG Jin-hai; ZHENG Yu

    2008-01-01

    In order to meet the requirements of real-time and high efficient data transmission in data acquisition and industrial control fields, a scheme of network communication interface is presented. The design of hardware circuit and the realization of software program are mainly introduced. The result of the experiment shows that this embedded system has high reliability and stability. It can realize high-speed data transmission, and also can satisfy the requirements of network communication in the industrial control fields.

  18. Adaptive routing in wireless communication networks using swarm intelligence

    Science.gov (United States)

    Arabshahi, P.; Gray, A.; Kassabalidis, I.; Das, A.; Narayanan, S.; Sharkawi, M. El; Marks, R. J.

    2001-01-01

    In this paper we focus on the network routing problem, and survey swarm intelligent approaches for its efficient solution, after a brief overview of power-aware routing schemes, which are important in the network examples outlined above.

  19. COMMUNICATION BY MEANS OF THE NEW SOCIAL NETWORKS

    OpenAIRE

    Purice Suzana; Enache Elena; Morozan Cristian

    2012-01-01

    In our days, the electronic communication media is important because the communication forms based on interactivity lead the participants in the act of sending and receiving information to become more than simply issuers, listeners or viewers, integrating them into a dynamic system. In this approach, the study paper aims to prove the relationship between personal development and that of society determined by the new interactive communication instruments. At the individual level, training, edu...

  20. The social network and communicative complexity: preface to theme issue

    OpenAIRE

    Todd M Freeberg; Ord, Terry J.; Dunbar, Robin I.M.

    2012-01-01

    The complex social worlds of many animal species may be linked to complex communicative systems in those species. We now have evidence in diverse taxa and in different communicative modalities suggesting that complexity in social groups can drive complexity in signalling systems. The aim of this theme issue is to develop the theory behind this link between social complexity and communicative complexity, and to provide an overview of the lines of research testing this link.

  1. European Automotive Congress

    CERN Document Server

    Clenci, Adrian

    2016-01-01

    The volume includes selected and reviewed papers from the European Automotive Congress held in Bucharest, Romania, in November 2015. Authors are experts from research, industry and universities coming from 14 countries worldwide. The papers are covering the latest developments in fuel economy and environment, automotive safety and comfort, automotive reliability and maintenance, new materials and technologies, traffic and road transport systems, advanced engineering methods and tools, as well as advanced powertrains and hybrid and electric drives.

  2. Social networks and the communication of norms about prenatal care in rural Mexico.

    Science.gov (United States)

    Lapinski, Maria Knight; Anderson, Jenn; Cruz, Shannon; Lapine, Peter

    2015-01-01

    Many normative beliefs are shared and learned through interpersonal communication, yet research on norms typically focuses on their effects rather than the communication that shapes them. This study focused on interpersonal communication during pregnancy to uncover (a) the nature of pregnancy-related communication and (b) normative information transmitted through such communication. Results from interviews with pregnant women living in rural Mexico revealed limited social networks; often, only a woman's mother or the baby's father were consulted about prenatal care decisions. However, women also indicated that communication with others during pregnancy provided important normative information regarding prenatal care. First, most referents believed that women should receive prenatal care (injunctive norm), which was conceptualized by participants as biomedical, nonmedical, or a blend of both. Second, family members often received prenatal care, whereas friends did not (descriptive norms). These findings highlight the key role of personal and social networks in shaping personal pregnancy-related beliefs and behaviors.

  3. How anxiety about communication affects the role of nurse leaders in international social networks.

    Science.gov (United States)

    Benton, David; Ferguson, Stephanie

    2016-05-01

    Social network analysis examines the way individuals are connected within groups or networks, and the role they play in these groups. In terms of its application to issues related to nurse leaders, much of the research focuses on the structure of their networks, the roles they play, and whether the networks can be changed to improve communication flows. This article reports results of a study that aimed to deepen understanding of how a particular trait - communication apprehension - can affect the roles that nurse leaders play within network structures. It also shows how the research expands understanding of the factors that influence connections between senior nurse leaders internationally, and describes the communication apprehension instrument used, which provides a practical tool to assist aspirant nurse leaders to identify areas for personal development.

  4. Network Identities And Communication: Social Constructivism And Social Constructionism Compared

    OpenAIRE

    Hopkinson, G.

    1999-01-01

    This paper explores the implications (methodological, theoretical and managerial) of social constructionism within a network context, especially through comparison with the related constructivist ideas previously applied in network contexts. The paper presents research from one network that demonstrates the application of constructionist ideas to research and highlights the managerial relevance of the philosophy.

  5. A Wireless Communications Laboratory on Cellular Network Planning

    Science.gov (United States)

    Dawy, Z.; Husseini, A.; Yaacoub, E.; Al-Kanj, L.

    2010-01-01

    The field of radio network planning and optimization (RNPO) is central for wireless cellular network design, deployment, and enhancement. Wireless cellular operators invest huge sums of capital on deploying, launching, and maintaining their networks in order to ensure competitive performance and high user satisfaction. This work presents a lab…

  6. A 2.4-GHz CMOS short-range wireless-sensor-network interface for automotive applications

    OpenAIRE

    Carmo, J.P.; Mendes, P.M.; Couto, Carlos; Correia, J.H.

    2010-01-01

    This paper describes a CMOS interface for shortrange wireless sensor networks (CMOS-SRWSN interface). The sensor interface is composed of a sensor readout, electronics for processing and control, a memory, a radio-frequency CMOS transceiver for operation in the 2.4-GHz industrial, scientific, and medical bands, and a planar antenna. The receiver has a sensitivity of −60 dBm and consumes 6.3 mW from a 1.8-V supply. The transmitter delivers an output power of 0 dBm with a p...

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

    Science.gov (United States)

    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 γ 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.

  8. Inter-organisational communication networks in healthcare: centralised versus decentralised approaches

    NARCIS (Netherlands)

    H. Pirnejad (Habibollah); R.A. Bal (Roland); A. Stoop; M. Berg (Marc)

    2007-01-01

    textabstractBackground: To afford efficient and high quality care, healthcare providers increasingly need to exchange patient data. The existence of a communication network amongst care providers will help them to exchange patient data more efficiently. Information and communication technology (ICT)

  9. The Integrated Communication: a Project for the Museum Network of Reggio Emilia

    OpenAIRE

    Chiara Coluccio

    2013-01-01

    This paper provides an analysis of the implementation phases of the Communication Plan for the Museum Network of Reggio Emilia. Moreover, this case study aims to point out the importance of cultural development policies oriented to the promotion of new models and strategies within the scope of the integrated communication

  10. An Improved Immune Genetic Algorithm for Solving the Optimization Problems of Computer Communication Networks

    Institute of Scientific and Technical Information of China (English)

    SUN Li-juan; LI Chao

    2003-01-01

    Obtaining the average delay and selecting a route in a communication network are multi-constrained nonlinear optimization problems. In this paper, based on the immune genetic algorithm, a new fuzzy self-adaptive mutation operator and a new upside-down code operator are proposed. This improved IGA is further successfully applied to solve optimal problems of computer communication nets.

  11. Project on Application of Modern Communication Technologies to Educational Networking. Final Technical Report.

    Science.gov (United States)

    Morgan, Robert P.; Eastwood, Lester F., Jr.

    Research on this National Science Foundation grant to study the application of modern communications technology to educational networking was divided into three parts: assessment of the role of technology in non-traditional post-secondary education; assessment of communications technologies and educational services of current or potential future…

  12. Low density parity check code in cooperative MIMO communication at wireless sensor network

    OpenAIRE

    Islam, Mohammad Rakibul; HOSSAIN, Md. Murad; Hoque, Md Ashraful; Islam, Kazi Khairul; Ullah, Md. Shahid

    2011-01-01

    Energy efficient data transmission is one of the key factors for energy constrained wireless sensor network. Cooperative communication explores the energy efficient wireless communication schemes between multiple sensors and data gathering node. In this paper, an energy efficient cooperative multiple input multiple output technique, which uses low density parity check codes, is suggested. The result shows that the suggested cooperative communication technique outperforms single input single o...

  13. NewMadeleine: a Fast Communication Scheduling Engine for High Performance Networks

    OpenAIRE

    Aumage, Olivier; Brunet, Elisabeth; Furmento, Nathalie; Namyst, Raymond

    2007-01-01

    Communication libraries have dramatically made progress over the fifteen years, pushed by the success of cluster architectures as the preferred platform for high performance distributed computing. However, many potential optimizations are left unexplored in the process of mapping application communication requests onto low level network commands. The fundamental cause of this situation is that the design of communication subsystems is mostly focused on reducing the latency by shortening the c...

  14. Transformation of Traditional Marketing Communications in to Paradigms of Social Media Networking

    OpenAIRE

    Nair, T. R. Gopalakrishnan; Subramaniam, Kumarashvari

    2012-01-01

    Effective Communication for marketing is a vital field in business organizations, which is used to convey the details about their products and services to the market segments and subsequently to build long lasting customer relationships. This paper focuses on an emerging component of the integrated marketing communication, ie. social media networking, as it is increasingly becoming the trend. In 21st century, the marketing communication platforms show a tendency to shift towards innovative te...

  15. Reach on Policy-based Transmition Control Technology in MPLS Communication Network

    Directory of Open Access Journals (Sweden)

    Jingyang Wang

    2012-07-01

    Full Text Available With the increasing variety of service types supported by the communication network, more and more requirements for bandwidth occurred. Different types of services have different characteristics in the aspects of importance, bandwidth demand, time-sensitive and so on. Customers’s requirements for the controllability and manageability of communication network are more and more demanding. The paper researches on policy-based transmition control technology in MPLS controllable and manageable communication network, proposes a new transmition control method. The method supports to create and to release the dynamical connection of MPLS TE or MPLS LSP, uses service-priority policy, bandwidth policy and degradation policy for policy decision. In order to improve the QoS of service-priority policy, Policy-Condition Maximum Matching Algorithm (PCMMA is put forward. The principle of the policy-based transmition control in the MPLS communication network is explained. An experiment is performed to support the research. The experiment results show that the policy-based transmition control technology in MPLS communication network is effective and valid. It helps to improve the QoS of network and the utilization rate of network resource.

  16. Dynamic Communication Performance Enhancement in Hierarchical Torus Network by Selection Algorithm

    Directory of Open Access Journals (Sweden)

    MM Hafizur Rahman

    2012-03-01

    Full Text Available A Hierarchical Torus Network (HTN is a 2D-torus network of multiple basic modules, in which the basic modules are 3D-torus networks that are hierarchically interconnected for higher-level networks. The static network performance of the HTN and its dynamic communication performance using the deterministic, dimension-order routing algorithm have already been evaluated and shown to be superior to the performance of other conventional and hierarchical interconnection networks. However, the assessment of the dynamic communication performance improvement of HTN by the efficient use of both the physical link and virtual channels has not yet been evaluated. This paper addresses three adaptive routing algorithms -- link-selection, channel-selection, and a combination of link-selection and channel-selection -- for the efficient use of physical links and virtual channels of an HTN to enhance dynamic communication performance. It also proves that the proposed adaptive routing algorithms are deadlock-free with 3 virtual channels. The dynamic communication performances of an HTN is evaluated by using dimension-order routing and proposed adaptive routing algorithms under various traffic patterns. It is found that the dynamic communication performance of an HTN using these adaptive routing algorithms are better than when the dimension-order routing is used, in terms of network throughput.

  17. Plastic optical fibers for automotive applications

    Science.gov (United States)

    Suganuma, Heiroku; Matsunaga, Tadayo

    1991-12-01

    High heat resistant optical fibers (POFs) have been developed for various automotive applications. Plastic chips with POF light guide have been used in place of a clearance monitor lamp. POF cords and cables have been used in the car-audio system, car-navigation system, and other data communication systems. This paper describes the structures, properties, and reliabilities of POFs for these applications.

  18. Packet Traffic Dynamics Near Onset of Congestion in Data Communication Network Model

    Science.gov (United States)

    Lawniczak, A. T.; Tang, X.

    2006-05-01

    The dominant technology of data communication networks is the Packet Switching Network (PSN). It is a complex technology organized as various hierarchical layers according to the International Standard Organization (ISO) Open Systems Interconnect (OSI) Reference Model. The Network Layer of the ISO OSI Reference Model is responsible for delivering packets from their sources to their destinations and for dealing with congestion if it arises in a network. Thus, we focus on this layer and present an abstraction of the Network Layer of the ISO OSI Reference Model. Using this abstraction we investigate how onset of traffic congestion is affected for various routing algorithms by changes in network connection topology. We study how aggregate measures of network performance depend on network connection topology and routing. We explore packets traffic spatio-temporal dynamics near the phase transition point from free flow to congestion for various network connection topologies and routing algorithms. We consider static and adaptive routings. We present selected simulation results.

  19. Verifying cell loss requirements in high-speed communication networks

    Directory of Open Access Journals (Sweden)

    Kerry W. Fendick

    1998-01-01

    Full Text Available In high-speed communication networks it is common to have requirements of very small cell loss probabilities due to buffer overflow. Losses are measured to verify that the cell loss requirements are being met, but it is not clear how to interpret such measurements. We propose methods for determining whether or not cell loss requirements are being met. A key idea is to look at the stream of losses as successive clusters of losses. Often clusters of losses, rather than individual losses, should be regarded as the important “loss events”. Thus we propose modeling the cell loss process by a batch Poisson stochastic process. Successive clusters of losses are assumed to arrive according to a Poisson process. Within each cluster, cell losses do not occur at a single time, but the distance between losses within a cluster should be negligible compared to the distance between clusters. Thus, for the purpose of estimating the cell loss probability, we ignore the spaces between successive cell losses in a cluster of losses. Asymptotic theory suggests that the counting process of losses initiating clusters often should be approximately a Poisson process even though the cell arrival process is not nearly Poisson. The batch Poisson model is relatively easy to test statistically and fit; e.g., the batch-size distribution and the batch arrival rate can readily be estimated from cell loss data. Since batch (cluster sizes may be highly variable, it may be useful to focus on the number of batches instead of the number of cells in a measurement interval. We also propose a method for approximately determining the parameters of a special batch Poisson cell loss with geometric batch-size distribution from a queueing model of the buffer content. For this step, we use a reflected Brownian motion (RBM approximation of a G/D/1/C queueing model. We also use the RBM model to estimate the input burstiness given the cell loss rate. In addition, we use the RBM model to

  20. Criteria for Evaluating Alternative Network and Link Layer Protocols for the NASA Constellation Program Communication Architecture

    Science.gov (United States)

    Benbenek, Daniel; Soloff, Jason; Lieb, Erica

    2010-01-01

    Selecting a communications and network architecture for future manned space flight requires an evaluation of the varying goals and objectives of the program, development of communications and network architecture evaluation criteria, and assessment of critical architecture trades. This paper uses Cx Program proposed exploration activities as a guideline; lunar sortie, outpost, Mars, and flexible path options are described. A set of proposed communications network architecture criteria are proposed and described. They include: interoperability, security, reliability, and ease of automating topology changes. Finally a key set of architecture options are traded including (1) multiplexing data at a common network layer vs. at the data link layer, (2) implementing multiple network layers vs. a single network layer, and (3) the use of a particular network layer protocol, primarily IPv6 vs. Delay Tolerant Networking (DTN). In summary, the protocol options are evaluated against the proposed exploration activities and their relative performance with respect to the criteria are assessed. An architectural approach which includes (a) the capability of multiplexing at both the network layer and the data link layer and (b) a single network layer for operations at each program phase, as these solutions are best suited to respond to the widest array of program needs and meet each of the evaluation criteria.