WorldWideScience

Sample records for technology user network

  1. Usability and use reference in the social network facebook: a netnographic analysis of technological users

    Directory of Open Access Journals (Sweden)

    Naiara Silva Ferreira

    2015-10-01

    Full Text Available This article presents a study about the preference of use in virtual social networks, using Facebook as object of study, to identify the motivational factors for the usability of this technology platform. The social network Facebook has been chosen to present a technological scenario of high sociability and virtual interaction. The methodology used was the netnography, being made through the collection of discussions in North American sites of news and forums online, where there is a large critical user participation on the internet, about the gains and frustrations in this context. The content analysis was performed comparing the categories of users found in the literature about values that motivate consumer technology, describing the hedonic, social, utilitarian values and perceptions of risk in consumption when related to lack of privacy. The results show two main groups of users of this technology and 7 subgroups. Therefore, the contribution of the study is that the formation of these groups may reflect technological usability of user groups around the world. The study also brings to the discussion issues related to the behaviors of the users of virtual networks which can be useful for businesses and their relationships with consumers and also the development of new knowledge from such criticism and demands that digital consumers expose about the technologies.

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

    Science.gov (United States)

    1992-01-01

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

  3. Usability and use reference in the social network facebook: a netnographic analysis of technological users

    OpenAIRE

    Naiara Silva Ferreira; Emílio José Montero Arruda Filho

    2015-01-01

    This article presents a study about the preference of use in virtual social networks, using Facebook as object of study, to identify the motivational factors for the usability of this technology platform. The social network Facebook has been chosen to present a technological scenario of high sociability and virtual interaction. The methodology used was the netnography, being made through the collection of discussions in North American sites of news and forums online, where there is a large cr...

  4. Using home networks to create atmospheres in the home: Technology push or (latent) user need?

    NARCIS (Netherlands)

    Kuiper-Hoyng, L.L.M.L.; Beusmans, J.W.F.

    2004-01-01

    The Atmosphere Controller is an implementation of home networking technology that could make life at home a totally new experience. An atmosphere is created by combining light (intensity and colour), music and wallpaper projection. To find out if is this type of experience fits into everyday life of

  5. Technological Networks

    Science.gov (United States)

    Mitra, Bivas

    The study of networks in the form of mathematical graph theory is one of the fundamental pillars of discrete mathematics. However, recent years have witnessed a substantial new movement in network research. The focus of the research is shifting away from the analysis of small graphs and the properties of individual vertices or edges to consideration of statistical properties of large scale networks. This new approach has been driven largely by the availability of technological networks like the Internet [12], World Wide Web network [2], etc. that allow us to gather and analyze data on a scale far larger than previously possible. At the same time, technological networks have evolved as a socio-technological system, as the concepts of social systems that are based on self-organization theory have become unified in technological networks [13]. In today’s society, we have a simple and universal access to great amounts of information and services. These information services are based upon the infrastructure of the Internet and the World Wide Web. The Internet is the system composed of ‘computers’ connected by cables or some other form of physical connections. Over this physical network, it is possible to exchange e-mails, transfer files, etc. On the other hand, the World Wide Web (commonly shortened to the Web) is a system of interlinked hypertext documents accessed via the Internet where nodes represent web pages and links represent hyperlinks between the pages. Peer-to-peer (P2P) networks [26] also have recently become a popular medium through which huge amounts of data can be shared. P2P file sharing systems, where files are searched and downloaded among peers without the help of central servers, have emerged as a major component of Internet traffic. An important advantage in P2P networks is that all clients provide resources, including bandwidth, storage space, and computing power. In this chapter, we discuss these technological networks in detail. The review

  6. User-centric networking future perspectives

    CERN Document Server

    Aldini, Alessandro

    2014-01-01

    This work represents a milestone for the? 'ULOOP User-centric Wireless Local Loop' project funded by the EU IST Seventh Framework Programme.ULOOP is focused on the robust, secure, and autonomic deployment of user-centric wireless networks. Contributions by ULOOP partners as well as invited tutorials by international experts in the field. The expected impact is to increase awareness to user-centric networking in terms, e.g., of business opportunities and quality of experience, and to present adequate technology to sustain the growth of user-friendly wireless architectures.Throughout the last 3

  7. User Privacy in RFID Networks

    Science.gov (United States)

    Singelée, Dave; Seys, Stefaan

    Wireless RFID networks are getting deployed at a rapid pace and have already entered the public space on a massive scale: public transport cards, the biometric passport, office ID tokens, customer loyalty cards, etc. Although RFID technology offers interesting services to customers and retailers, it could also endanger the privacy of the end-users. The lack of protection mechanisms being deployed could potentially result in a privacy leakage of personal data. Furthermore, there is the emerging threat of location privacy. In this paper, we will show some practical attack scenarios and illustrates some of them with cases that have received press coverage. We will present the main challenges of enhancing privacy in RFID networks and evaluate some solutions proposed in literature. The main advantages and shortcomings will be briefly discussed. Finally, we will give an overview of some academic and industrial research initiatives on RFID privacy.

  8. Technological development and user preference estimation of a Start-up based on the social networks

    OpenAIRE

    Bastida Raja, Judit

    2017-01-01

    The proposed TFG covers the analysis, planing, development, implementation and maintenance of a process of technological growth of an startup. This Thesis means not only the end of a stage, is the link between the academic life and an alive business project. In this thesis it is explained how I could take profit of my technological skills and make of Lemon’s Secrets, my Start-up, a modernised, more efficient and up to date company. In this thesis is carried up an analysis of our c...

  9. Network user's guide

    International Nuclear Information System (INIS)

    McGrady, P.W.

    1994-12-01

    NETWORK is a FORTRAN code used to model process flow systems in the gaseous diffusion plants at Portsmouth, Ohio and Paducah, Kentucky, operated by the United States Enrichment Corporation. It can handle a wide range of components and several different types of controllers. NETWORK can be run in either a steady-state mode or a transient mode. In the transient mode many different types of perturbations may be modeled. It is currently being used to model taking a cell off-stream in a gaseous diffusion plant. A brief description of the code is given, and process equipment models and input data are discussed

  10. SDN Based User-Centric Framework for Heterogeneous Wireless Networks

    Directory of Open Access Journals (Sweden)

    Zhaoming Lu

    2016-01-01

    Full Text Available Due to the rapid growth of mobile data traffic, more and more basestations and access points (APs have been densely deployed to provide users with ubiquitous network access, which make current wireless network a complex heterogeneous network (HetNet. However, traditional wireless networks are designed with network-centric approaches where different networks have different quality of service (QoS strategies and cannot easily cooperate with each other to serve network users. Massive network infrastructures could not assure users perceived network and service quality, which is an indisputable fact. To address this issue, we design a new framework for heterogeneous wireless networks with the principle of user-centricity, refactoring the network from users’ perspective to suffice their requirements and preferences. Different from network-centric approaches, the proposed framework takes advantage of Software Defined Networking (SDN and virtualization technology, which will bring better perceived services quality for wireless network users. In the proposed user-centric framework, control plane and data plane are decoupled to manage the HetNets in a flexible and coadjutant way, and resource virtualization technology is introduced to abstract physical resources of HetNets into unified virtualized resources. Hence, ubiquitous and undifferentiated network connectivity and QoE (quality of experience driven fine-grained resource management could be achieved for wireless network users.

  11. Social networks user: current research

    OpenAIRE

    Agadullina E.R.

    2015-01-01

    The purpose of this article is to review current research studies focusing on the users of Facebook and their behaviors in social networks. This review is organized into two sections: 1) social-demographic characteristics (Age, Gender, Nationality); 2) personality characteristics (Neuroticism, Extraversion, Openness-to-Experience, Agreeableness, Conscientiousness, Narcissism, Self-esteem). The results showed that the information in the personal profile and online behavior are strongly connect...

  12. Social networks user: current research

    Directory of Open Access Journals (Sweden)

    Agadullina E.R.

    2015-12-01

    Full Text Available The purpose of this article is to review current research studies focusing on the users of Facebook and their behaviors in social networks. This review is organized into two sections: 1 social-demographic characteristics (Age, Gender, Nationality; 2 personality characteristics (Neuroticism, Extraversion, Openness-to-Experience, Agreeableness, Conscientiousness, Narcissism, Self-esteem. The results showed that the information in the personal profile and online behavior are strongly connected with socio-demographic and personality characteristics

  13. User research & technology, pt.2

    CERN Document Server

    Greifeneder, Elke

    2011-01-01

    This e-book is Part 2 on the theme "User Research and Technology". The research covers the testing of online digital library resources using various methods. Library and information science as a field is changing and the requirements for top quality research are growing more stringent. This is typical of the experience of other professional fields as they have moved from practitioners advising practitioners to researchers building on past results. This e-book contains 12 papers on this theme.

  14. A Secure Mobility Network Authentication Scheme Ensuring User Anonymity

    Directory of Open Access Journals (Sweden)

    Ya-Fen Chang

    2017-12-01

    Full Text Available With the rapid growth of network technologies, users are used to accessing various services with their mobile devices. To ensure security and privacy in mobility networks, proper mechanisms to authenticate the mobile user are essential. In this paper, a mobility network authentication scheme based on elliptic curve cryptography is proposed. In the proposed scheme, a mobile user can be authenticated without revealing who he is for user anonymity, and a session key is also negotiated to protect the following communications. The proposed mobility network authentication scheme is analyzed to show that it can ensure security, user anonymity, and convenience. Moreover, Burrows-Abadi-Needham logic (BAN logic is used to deduce the completeness of the proposed authentication scheme.

  15. Technologies for Home Networking

    DEFF Research Database (Denmark)

    A broad overview of the home networking field, ranging from wireless technologies to practical applications. In the future, it is expected that private networks (e.g. home networks) will become part of the global network ecosystem, participating in sharing their own content, running IP...

  16. Distributed Bayesian Networks for User Modeling

    DEFF Research Database (Denmark)

    Tedesco, Roberto; Dolog, Peter; Nejdl, Wolfgang

    2006-01-01

    The World Wide Web is a popular platform for providing eLearning applications to a wide spectrum of users. However – as users differ in their preferences, background, requirements, and goals – applications should provide personalization mechanisms. In the Web context, user models used...... by such adaptive applications are often partial fragments of an overall user model. The fragments have then to be collected and merged into a global user profile. In this paper we investigate and present algorithms able to cope with distributed, fragmented user models – based on Bayesian Networks – in the context...... of Web-based eLearning platforms. The scenario we are tackling assumes learners who use several systems over time, which are able to create partial Bayesian Networks for user models based on the local system context. In particular, we focus on how to merge these partial user models. Our merge mechanism...

  17. Identifying online user reputation of user-object bipartite networks

    Science.gov (United States)

    Liu, Xiao-Lu; Liu, Jian-Guo; Yang, Kai; Guo, Qiang; Han, Jing-Ti

    2017-02-01

    Identifying online user reputation based on the rating information of the user-object bipartite networks is important for understanding online user collective behaviors. Based on the Bayesian analysis, we present a parameter-free algorithm for ranking online user reputation, where the user reputation is calculated based on the probability that their ratings are consistent with the main part of all user opinions. The experimental results show that the AUC values of the presented algorithm could reach 0.8929 and 0.8483 for the MovieLens and Netflix data sets, respectively, which is better than the results generated by the CR and IARR methods. Furthermore, the experimental results for different user groups indicate that the presented algorithm outperforms the iterative ranking methods in both ranking accuracy and computation complexity. Moreover, the results for the synthetic networks show that the computation complexity of the presented algorithm is a linear function of the network size, which suggests that the presented algorithm is very effective and efficient for the large scale dynamic online systems.

  18. User-Centric Secure Cross-Site Interaction Framework for Online Social Networking Services

    Science.gov (United States)

    Ko, Moo Nam

    2011-01-01

    Social networking service is one of major technological phenomena on Web 2.0. Hundreds of millions of users are posting message, photos, and videos on their profiles and interacting with other users, but the sharing and interaction are limited within the same social networking site. Although users can share some content on a social networking site…

  19. Recognizing Multi-user Activities using Body Sensor Networks

    DEFF Research Database (Denmark)

    Gu, Tao; Wang, Liang; Chen, Hanhua

    2011-01-01

    activity classes of data—for building activity models and design a scalable, noise-resistant, Emerging Pattern based Multi-user Activity Recognizer (epMAR) to recognize both single- and multi-user activities. We develop a multi-modal, wireless body sensor network for collecting real-world traces in a smart......The advances of wireless networking and sensor technology open up an interesting opportunity to infer human activities in a smart home environment. Existing work in this paradigm focuses mainly on recognizing activities of a single user. In this work, we address the fundamental problem...... of recognizing activities of multiple users using a wireless body sensor network, and propose a scalable pattern mining approach to recognize both single- and multi-user activities in a unified framework. We exploit Emerging Pattern—a discriminative knowledge pattern which describes significant changes among...

  20. A User Driven Dynamic Circuit Network Implementation

    Energy Technology Data Exchange (ETDEWEB)

    Guok, Chin; Robertson, David; Chaniotakis, Evangelos; Thompson, Mary; Johnston, William; Tierney, Brian

    2008-10-01

    The requirements for network predictability are becoming increasingly critical to the DoE science community where resources are widely distributed and collaborations are world-wide. To accommodate these emerging requirements, the Energy Sciences Network has established a Science Data Network to provide user driven guaranteed bandwidth allocations. In this paper we outline the design, implementation, and secure coordinated use of such a network, as well as some lessons learned.

  1. The Role of Cultural and Identity Differences in Self-expression of Iranian Users of Social Networking Sites; A Case Study of Students of Tehran University, Amirkabir University, and Sharif University of Technology

    Directory of Open Access Journals (Sweden)

    H. Molaei

    2017-12-01

    Full Text Available Social media with their features such as interactivity, participatory, and user-generated content have provided a great opportunity for self-expression of the users. However, cultural differences affect the extent and modality of users’ self-expression. This study aims to investigate the modality of self-expression of Iranian users of the social networking sites. In doing so, an online survey was conducted among the students of three Iran universities: University of Tehran, Amirkabir University of Technology, and Sharif University of Technology. A total of 371 students participated in the study. Having conducted quantitative analysis, the study results showed that women and ethnic minorities are more inclined to support their cultural differences compared to men and ethnic majority group. Supporting cultural differences was observed more among Shia religious majority group. Religious minorities expressed less tendency to create content in social networking sites and as a result support their religious identity.

  2. Segmentation of users of social networking websites

    NARCIS (Netherlands)

    Lorenzo-Romero, C.; Alarcon-del-Amo, M.d.C.; Constantinides, Efthymios

    2012-01-01

    The typology of networked consumers in The Netherlands presented in this study, was based on an online survey and obtained using latent segmentation analysis. This approach is based on the frequency with which users perform different activities, their sociodemographic variables, social networking

  3. User innovation in sustainable home energy technologies

    International Nuclear Information System (INIS)

    Hyysalo, Sampsa; Juntunen, Jouni K.; Freeman, Stephanie

    2013-01-01

    The new millennium has marked an increasing interest in citizens as energy end-users. While much hope has been placed on more active energy users, it has remained less clear what citizens can and are willing to do. We charted user inventions in heat pump and wood pellet burning systems in Finland in years 2005–2012. In total we found 192 inventions or modifications that improved either the efficiency, suitability, usability, maintenance or price of the heat pump or pellet systems, as evaluated by domain experts. Our analysis clarifies that users are able to successfully modify, improve and redesign next to all subsystems in these technologies. It appears that supplier models do not cater sufficiently for the variation in users' homes, which leaves unexplored design space for users to focus on. The inventive users can speed up the development and proliferation of distributed renewable energy technologies both through their alternative designs as well as through the advanced peer support they provide in popular user run Internet forums related to the purchase, use and maintenance of these technologies. There are several implications for how such users can be of benefit to energy and climate policy as well as how to support them. - Highlights: ► We clarify how citizen users are able to invent in home heating systems. ► We researched inventions that users did to heat pump and wood pellet burning systems. ► During the years 2005–2012 there were 192 inventions by users in Finland alone. ► Users were able to invent in practically all subsystems of these technologies. ► Users’ ability merits policy attention and can lead to new types of policy action

  4. Binary Classification Method of Social Network Users

    Directory of Open Access Journals (Sweden)

    I. A. Poryadin

    2017-01-01

    Full Text Available The subject of research is a binary classification method of social network users based on the data analysis they have placed. Relevance of the task to gain information about a person by examining the content of his/her pages in social networks is exemplified. The most common approach to its solution is a visual browsing. The order of the regional authority in our country illustrates that its using in school education is needed. The article shows restrictions on the visual browsing of pupil’s pages in social networks as a tool for the teacher and the school psychologist and justifies that a process of social network users’ data analysis should be automated. Explores publications, which describe such data acquisition, processing, and analysis methods and considers their advantages and disadvantages. The article also gives arguments to support a proposal to study the classification method of social network users. One such method is credit scoring, which is used in banks and credit institutions to assess the solvency of clients. Based on the high efficiency of the method there is a proposal for significant expansion of its using in other areas of society. The possibility to use logistic regression as the mathematical apparatus of the proposed method of binary classification has been justified. Such an approach enables taking into account the different types of data extracted from social networks. Among them: the personal user data, information about hobbies, friends, graphic and text information, behaviour characteristics. The article describes a number of existing methods of data transformation that can be applied to solve the problem. An experiment of binary gender-based classification of social network users is described. A logistic model obtained for this example includes multiple logical variables obtained by transforming the user surnames. This experiment confirms the feasibility of the proposed method. Further work is to define a system

  5. Creating Profiles from User Network Behavior

    Science.gov (United States)

    2013-09-01

    or corporate office . User network behavior differs based on the user’s location [17], and it makes sense that traffic from an office building might...the Computer Science Department at NPS is not a per- fect replacement for traffic from a government or corporate office , we believe it is a reasonable...N. Taft, “The cubicle vs. the coffee shop: behavioral modes in enterprise end-users,” in Proc. of the 9th Int. Conf. on Passive and Active Network

  6. Numerical Representations and User Behaviour in Social Networking Sites

    DEFF Research Database (Denmark)

    Sjöklint, Mimmi; Constantiou, Ioanna; Trier, Matthias

    2013-01-01

    The new technological enhancements and the accessibility to varieties of online applications, enable users to collect personal data and perform self-evaluation through test, comparison and experimentation. The sparked interest in numbers and numbers as self-representative visualisations is promin......The new technological enhancements and the accessibility to varieties of online applications, enable users to collect personal data and perform self-evaluation through test, comparison and experimentation. The sparked interest in numbers and numbers as self-representative visualisations...... is prominent in social networking sites, which are the empirical setting for the present study. This paper sets out to establish a multi-theoretical framework which enables the investigation of emerging phenomena of the role of numbers in social networking sites. The proposed framework rests on three...... theoretical pillars: self-determination theory, heuristic decision making and behavioural economics. A discussion departs from these convictions to investigate user reactions and behaviour when faced with numerical representations in the SNS....

  7. User-centric technology design for nonprofit and civic engagements

    CERN Document Server

    Saeed, Saqib

    2014-01-01

    Due to the increased global political importance of the nonprofit sector, its technological support and organizational characteristics have become important fields of research. In order to conduct effective work, nonprofits need to communicate and coordinate effectively. However, such settings are generally characterized by a lack of resources, an absence of formal hierarchical structures and differences in languages and culture among the activists. Modern technologies could help nonprofit networks in improving their working. In order to design appropriate technological support for such settings, it is important to understand their work practices, which widely differ from traditional business organizations. This book aims to strengthen the body of knowledge by providing user studies and concepts related to user centered technology design process for nonprofit settings. The examination of ethnographic studies and user centered evaluation of IT artifacts in practice will further the understanding of design requ...

  8. User driven innovation in mobile technologies?

    DEFF Research Database (Denmark)

    Larsen, Casper Schultz; Koch, Christian

    2007-01-01

    Developing dedicated mobile technology systems for AEC demands the introduction of user driven innovation. A Danish research project collected international examples and user-experiences of mobile and handheld ICT in the building industry i.a. by reading off the functionality of the mobile...... technology systems relying on the concept of affordance. This paper examines how innovation processes mediate between user orientations and technology offers. There is a great potential for mobile handheld ICT-systems to support numerous work processes in the AEC-industry and this can be substantiated...... by systems already in function. Stories of prior business successes can be an important tool to ensure further innovative investments since lack of enterprise strategies is often an obstacle for innovation, especially user driven. Both small and large software houses develops dedicated software for coupling...

  9. Understanding active and passive users: the effects of an active user using normal, hard and unreliable technologies on user assessment of trust in technology and co-user.

    Science.gov (United States)

    Montague, Enid; Xu, Jie

    2012-07-01

    The aim of this study was to understand how passive users perceive the trustworthiness of active users and technologies under varying technological conditions. An experimental study was designed to vary the functioning of technologies that active users interacted with, while passive users observed these interactions. Active and passive user ratings of technology and partner were collected. Exploratory data analysis suggests that passive users developed perceptions of technologies based on the functioning of the technology and how the active user interacted with the technology. Findings from this research have implications for the design of technologies in environments where active and passive users interact with technologies in different ways. Future work in this area should explore interventions that lead to enhanced affective engagement and trust calibration. Published by Elsevier Ltd.

  10. Understanding Active and Passive Users: The Effects of an Active User Using Normal, Hard and Unreliable Technologies on User Assessment of Trust in Technology and Co-User

    Science.gov (United States)

    Montague, Enid; JieXu

    2011-01-01

    The aim of this study was to understand how passive users perceive the trustworthiness of active users and technologies under varying technological conditions. An experimental study was designed to vary the functioning of technologies that active users interacted with, while passive users observed these interactions. Active and passive user ratings of technology and partner were collected. Exploratory data analysis suggests that passive users developed perceptions of technologies based on the functioning of the technology and how the active user interacted with the technologies. Findings from this research have implications for the design of technologies in environments where active and passive users interact with technologies in different ways. Future work in this area should explore interventions that lead to enhanced affective engagement and trust calibration. PMID:22192788

  11. User Interface Technology for Formal Specification Development

    Science.gov (United States)

    Lowry, Michael; Philpot, Andrew; Pressburger, Thomas; Underwood, Ian; Lum, Henry, Jr. (Technical Monitor)

    1994-01-01

    Formal specification development and modification are an essential component of the knowledge-based software life cycle. User interface technology is needed to empower end-users to create their own formal specifications. This paper describes the advanced user interface for AMPHION1 a knowledge-based software engineering system that targets scientific subroutine libraries. AMPHION is a generic, domain-independent architecture that is specialized to an application domain through a declarative domain theory. Formal specification development and reuse is made accessible to end-users through an intuitive graphical interface that provides semantic guidance in creating diagrams denoting formal specifications in an application domain. The diagrams also serve to document the specifications. Automatic deductive program synthesis ensures that end-user specifications are correctly implemented. The tables that drive AMPHION's user interface are automatically compiled from a domain theory; portions of the interface can be customized by the end-user. The user interface facilitates formal specification development by hiding syntactic details, such as logical notation. It also turns some of the barriers for end-user specification development associated with strongly typed formal languages into active sources of guidance, without restricting advanced users. The interface is especially suited for specification modification. AMPHION has been applied to the domain of solar system kinematics through the development of a declarative domain theory. Testing over six months with planetary scientists indicates that AMPHION's interactive specification acquisition paradigm enables users to develop, modify, and reuse specifications at least an order of magnitude more rapidly than manual program development.

  12. RUASN: A Robust User Authentication Framework for Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Hoon-Jae Lee

    2011-05-01

    Full Text Available In recent years, wireless sensor networks (WSNs have been considered as a potential solution for real-time monitoring applications and these WSNs have potential practical impact on next generation technology too. However, WSNs could become a threat if suitable security is not considered before the deployment and if there are any loopholes in their security, which might open the door for an attacker and hence, endanger the application. User authentication is one of the most important security services to protect WSN data access from unauthorized users; it should provide both mutual authentication and session key establishment services. This paper proposes a robust user authentication framework for wireless sensor networks, based on a two-factor (password and smart card concept. This scheme facilitates many services to the users such as user anonymity, mutual authentication, secure session key establishment and it allows users to choose/update their password regularly, whenever needed. Furthermore, we have provided the formal verification using Rubin logic and compare RUASN with many existing schemes. As a result, we found that the proposed scheme possesses many advantages against popular attacks, and achieves better efficiency at low computation cost.

  13. Software Defined Networking Demands on Software Technologies

    DEFF Research Database (Denmark)

    Galinac Grbac, T.; Caba, Cosmin Marius; Soler, José

    2015-01-01

    Software Defined Networking (SDN) is a networking approach based on a centralized control plane architecture with standardised interfaces between control and data planes. SDN enables fast configuration and reconfiguration of the network to enhance resource utilization and service performances....... This new approach enables a more dynamic and flexible network, which may adapt to user needs and application requirements. To this end, systemized solutions must be implemented in network software, aiming to provide secure network services that meet the required service performance levels. In this paper......, we review this new approach to networking from an architectural point of view, and identify and discuss some critical quality issues that require new developments in software technologies. These issues we discuss along with use case scenarios. Here in this paper we aim to identify challenges...

  14. Feedback from Users of Electronic Chart Technology

    Science.gov (United States)

    Edmonds, David

    This paper was presented at the Third Electronic Chart Technology Conference, SASMEX International, Brighton, 22-23 April 1998.Electronic Chart Systems have been used by mariners across the entire user spectrum without official standards or specifications for 10 years. In the last three years, the debate has centred on chart data and the merits of differing cartographic technologies. There is little new that can be said for or against raster or vector technologies except what actual users might say to support the requirements of their day-to-day operations. Today, we approach a new stage as ENCs start to become available but only for limited areas. This in turn means that ENCs are capable of supporting the only approved electronic chart system, ECDIS, in a limited way. There is an urgent need for alternatives to ECDIS to cover those areas where ENCs will continue to be unavailable for the foreseeable future. This paper therefore summarizes a feedback from users of RCDS and ECDIS-type systems to demonstrate the benefits which can be secured from official recognition of RCDS systems as the legal equivalent of paper chart navigation.

  15. Identification of influential users by neighbors in online social networks

    Science.gov (United States)

    Sheikhahmadi, Amir; Nematbakhsh, Mohammad Ali; Zareie, Ahmad

    2017-11-01

    Identification and ranking of influential users in social networks for the sake of news spreading and advertising has recently become an attractive field of research. Given the large number of users in social networks and also the various relations that exist among them, providing an effective method to identify influential users has been gradually considered as an essential factor. In most of the already-provided methods, those users who are located in an appropriate structural position of the network are regarded as influential users. These methods do not usually pay attention to the interactions among users, and also consider those relations as being binary in nature. This paper, therefore, proposes a new method to identify influential users in a social network by considering those interactions that exist among the users. Since users tend to act within the frame of communities, the network is initially divided into different communities. Then the amount of interaction among users is used as a parameter to set the weight of relations existing within the network. Afterward, by determining the neighbors' role for each user, a two-level method is proposed for both detecting users' influence and also ranking them. Simulation and experimental results on twitter data shows that those users who are selected by the proposed method, comparing to other existing ones, are distributed in a more appropriate distance. Moreover, the proposed method outperforms the other ones in terms of both the influential speed and capacity of the users it selects.

  16. Implementation readiness for user-driven innovation in business networks

    DEFF Research Database (Denmark)

    Lassen, Astrid Heidemann; Jacobsen, Alexia

    2013-01-01

    In this paper we further develop the concept of implementation readiness of user driven innovation in business networks by focusing on how implementation readiness activities are in fact needed not only at the early stages of such network collaboration, but continuously throughout the process...... of developing user-driven innovation in business networks....

  17. User-centered Technologies For Blind Children

    Directory of Open Access Journals (Sweden)

    Jaime Sánchez

    2008-01-01

    Full Text Available The purpose of this paper is to review, summarize, and illustrate research work involving four audio-based games created within a user-centered design methodology through successive usability tasks and evaluations. These games were designed by considering the mental model of blind children and their styles of interaction to perceive and process data and information. The goal of these games was to enhance the cognitive development of spatial structures, memory, haptic perception, mathematical skills, navigation and orientation, and problem solving of blind children. Findings indicate significant improvements in learning and cognition from using audio-based tools specially tailored for the blind. That is, technologies for blind children, carefully tailored through user-centered design approaches, can make a significant contribution to cognitive development of these children. This paper contributes new insight into the design and implementation of audio-based virtual environments to facilitate learning and cognition in blind children.

  18. Sensor Network-Based and User-Friendly User Location Discovery for Future Smart Homes.

    Science.gov (United States)

    Ahvar, Ehsan; Lee, Gyu Myoung; Han, Son N; Crespi, Noel; Khan, Imran

    2016-06-27

    User location is crucial context information for future smart homes where many location based services will be proposed. This location necessarily means that User Location Discovery (ULD) will play an important role in future smart homes. Concerns about privacy and the need to carry a mobile or a tag device within a smart home currently make conventional ULD systems uncomfortable for users. Future smart homes will need a ULD system to consider these challenges. This paper addresses the design of such a ULD system for context-aware services in future smart homes stressing the following challenges: (i) users' privacy; (ii) device-/tag-free; and (iii) fault tolerance and accuracy. On the other hand, emerging new technologies, such as the Internet of Things, embedded systems, intelligent devices and machine-to-machine communication, are penetrating into our daily life with more and more sensors available for use in our homes. Considering this opportunity, we propose a ULD system that is capitalizing on the prevalence of sensors for the home while satisfying the aforementioned challenges. The proposed sensor network-based and user-friendly ULD system relies on different types of inexpensive sensors, as well as a context broker with a fuzzy-based decision-maker. The context broker receives context information from different types of sensors and evaluates that data using the fuzzy set theory. We demonstrate the performance of the proposed system by illustrating a use case, utilizing both an analytical model and simulation.

  19. User Identification Framework in Social Network Services Environment

    Directory of Open Access Journals (Sweden)

    Brijesh BAKARIYA

    2014-01-01

    Full Text Available Social Network Service is a one of the service where people may communicate with one an-other; and may also exchange messages even of any type of audio or video communication. Social Network Service as name suggests a type of network. Such type of web application plays a dominant role in internet technology. In such type of online community, people may share their common interest. Facebook LinkedIn, orkut and many more are the Social Network Service and it is good medium of making link with people having unique or common interest and goals. But the problem of privacy protection is a big issue in today’s world. As social networking sites allows anonymous users to share information of other stuffs. Due to which cybercrime is also increasing to a rapid extent. In this article we preprocessed the web log data of Social Network Services and assemble that data on the basis of image file format like jpg, jpeg, gif, png, bmp etc. and also propose a framework for victim’s identification.

  20. An Overview of Computer Network security and Research Technology

    OpenAIRE

    Rathore, Vandana

    2016-01-01

    The rapid development in the field of computer networks and systems brings both convenience and security threats for users. Security threats include network security and data security. Network security refers to the reliability, confidentiality, integrity and availability of the information in the system. The main objective of network security is to maintain the authenticity, integrity, confidentiality, availability of the network. This paper introduces the details of the technologies used in...

  1. Sensor Network-Based and User-Friendly User Location Discovery for Future Smart Homes

    Directory of Open Access Journals (Sweden)

    Ehsan Ahvar

    2016-06-01

    Full Text Available User location is crucial context information for future smart homes where many location based services will be proposed. This location necessarily means that User Location Discovery (ULD will play an important role in future smart homes. Concerns about privacy and the need to carry a mobile or a tag device within a smart home currently make conventional ULD systems uncomfortable for users. Future smart homes will need a ULD system to consider these challenges. This paper addresses the design of such a ULD system for context-aware services in future smart homes stressing the following challenges: (i users’ privacy; (ii device-/tag-free; and (iii fault tolerance and accuracy. On the other hand, emerging new technologies, such as the Internet of Things, embedded systems, intelligent devices and machine-to-machine communication, are penetrating into our daily life with more and more sensors available for use in our homes. Considering this opportunity, we propose a ULD system that is capitalizing on the prevalence of sensors for the home while satisfying the aforementioned challenges. The proposed sensor network-based and user-friendly ULD system relies on different types of inexpensive sensors, as well as a context broker with a fuzzy-based decision-maker. The context broker receives context information from different types of sensors and evaluates that data using the fuzzy set theory. We demonstrate the performance of the proposed system by illustrating a use case, utilizing both an analytical model and simulation.

  2. An Empirical Study Of User Acceptance Of Online Social Networks Marketing

    Directory of Open Access Journals (Sweden)

    Olumayowa Mulero

    2013-07-01

    Full Text Available The explosion of Internet usage has drawn the attention of researchers towards online Social Networks Marketing (SNM. Research has shown that a number of the Internet users are distrustful and indecisive, when it comes to the use of social networks marketing system. Therefore, there is a need for researchers to identify some of the factors that determine users’ acceptance of social networks marketing using Technology Acceptance Model (TAM. This study extended the Technology Acceptance Model theoretical framework to predict consumer acceptance of social networks marketing within Western Cape Province of South Africa. The research model was tested using data collected from 470 questionnaires and analysed using linear regression. The results showed that user intentions to use SNM are strongly and positively correlated with user acceptance of using SNM systems. Empirical results confirmed that perceived credibility and perceived usefulness are the strongest determinant in predicting user intentions to use SNM system.

  3. How users matter : The co-construction of users and technologies

    NARCIS (Netherlands)

    Oudshoorn, Nelly E.J.; Pinch, Trevor

    2003-01-01

    Users have become an integral part of technology studies. The essays in this volume look at the creative capacity of users to shape technology in all phases, from design to implementation. Using a variety of theoretical approaches, including a feminist focus on users and use (in place of the

  4. Privacy-preserving user clustering in a social network

    NARCIS (Netherlands)

    Erkin, Z.; Veugen, P.J.M.; Toft, T.; Lagendijk, R.L.

    2009-01-01

    In a ubiquitously connected world, social networks are playing an important role on the Internet by allowing users to find groups of people with similar interests. The data needed to construct such networks may be considered sensitive personal information by the users, which raises privacy concerns.

  5. Library User Education under the Circumstance of Network

    Science.gov (United States)

    Zhu, Tian-hui

    2009-01-01

    Based on the concept of user education, this paper discusses the necessity of user education in library under the circumstance of network, describes the contents and forms of user education and puts forward the problems that should be paid attention to during education. [This paper was supported by scientific research project of Qufu Normal…

  6. Performance of an opportunistic multi-user cognitive network with multiple primary users

    KAUST Repository

    Khan, Fahd Ahmed

    2014-04-01

    Consider a multi-user underlay cognitive network where multiple cognitive users, having limited peak transmit power, concurrently share the spectrum with a primary network with multiple users. The channel between the secondary network is assumed to have independent but not identical Nakagami-m fading. The interference channel between the secondary users and the primary users is assumed to have Rayleigh fading. The uplink scenario is considered where a single secondary user is selected for transmission. This opportunistic selection depends on the transmission channel power gain and the interference channel power gain as well as the power allocation policy adopted at the users. Exact closed form expressions for the momentgenerating function, outage performance and the symbol-error-rate performance are derived. The outage performance is also studied in the asymptotic regimes and the generalized diversity gain of this scheduling scheme is derived. Numerical results corroborate the derived analytical results.

  7. The Role of Cultural and Identity Differences in Self-expression of Iranian Users of Social Networking Sites; A Case Study of Students of Tehran University, Amirkabir University, and Sharif University of Technology

    OpenAIRE

    H. Molaei; Z. Majdizadeh

    2017-01-01

    Social media with their features such as interactivity, participatory, and user-generated content have provided a great opportunity for self-expression of the users. However, cultural differences affect the extent and modality of users’ self-expression. This study aims to investigate the modality of self-expression of Iranian users of the social networking sites. In doing so, an online survey was conducted among the students of three Iran universities: University of Tehran, Amirkabir Universi...

  8. Networked Constellation Communications Technologies

    Data.gov (United States)

    National Aeronautics and Space Administration — Develop communications architectures and enabling technologies for mission concepts relying on multiple spatially distributed spacecraft to perform coordinated...

  9. A social network perspective of lead users and creativity

    DEFF Research Database (Denmark)

    Kratzer, Jan; Lettl, Christopher

    2008-01-01

    Generating ideas at the 'fuzzy front end' of new product development is risky and has serious consequences for all preceding development stages. One of the currently most prominent techniques in supporting this idea-generation stage is the lead user approach. Involving lead users in idea generation...... closely correlates to individual creativity, and both, in turn, to the provision of information in social networks. This study, guided by lead user theory, creativity research and network theory, investigates 16 school-groups of children examining the relationship between the children's social networks...... and their resulting creativity and lead userness. In addition, the interplay between lead userness and creativity is discussed and empirically tested. The main result of this study is that children who are positioned as bridging links between different groups in social networks reveal both a high degree of lead...

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

    Science.gov (United States)

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

    2006-01-01

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

  11. 75 FR 63253 - State-56, Network User Account Records

    Science.gov (United States)

    2010-10-14

    ..., platforms, services, applications, and databases within a Department network; to monitor security of... Administration, U.S. Department of State. STATE-56 SYSTEM NAME: Network User Account Records. SECURITY..., and databases within a Department network; to monitor security of computer systems; to investigate and...

  12. 11th European VLBI Network Symposium & Users Meeting

    Science.gov (United States)

    The Laboratoire d'Astrophysique de Bordeaux (LAB) at the University of Bordeaux (France), on behalf of the European VLBI Consortium, hosted the 11th European VLBI Network (EVN) Symposium and EVN Users Meeting on October 9-12, 2012. The Symposium was held at the "Chambre de Commerce et d'Industrie de Bordeaux", located in the "Palais de la Bourse", in the center of Bordeaux. The conference highlighted the latest scientific results and technical developments from VLBI, space VLBI and e-VLBI. All fields of astrophysics were concerned - stellar, galactic and extragalactic - as well as astrometry and planetary science. Presentations addressing synergy between (e-)VLBI and other new or planned radio facilities (ALMA, LOFAR, e-MERLIN,...) or instruments at other wavelengths (Fermi, CTA, Gaia,...) were also an integral part of the program. The scientific program was organized in 11 sessions including 71 oral presentations, with an additional 43 posters available for viewing during the entire length of the conference. An EVN Users Meeting was also held during one of the evening to foster interaction between the EVN users and the EVN organization. The symposium was attended by a total of 122 delegates originating from 47 institutes world-wide, sharing new VLBI science and innovations while also building links with other communities. The research leading to these results has received funding from the European Union's Seventh Framework Programme for research, technological development and demonstration under grant agreement no 283393 (RadioNet3).

  13. Technology for the Next-Generation-Mobile User Experience

    Science.gov (United States)

    Delagi, Greg

    specialized circuits, highly parallel architectures, and new packaging design. Another concern of the smart-mobile-companion user will be that their device is able to deliver an always-on, always-aware environment in a way that is completely seamless and transparent. These handsets will automatically determine the best and most appropriate modem link from the multiple choices on the device, including WiFi, LTE, 5G, and mmWave, based on which link will optimize performance, battery life, and network charges to deliver the best possible user experience. In the future, adaptive connectivity will require many different solutions, including the standard modem technologies of today, as well as new machine-machine interfaces and body-area-networks. All of the new and exciting applications and features of these mobile-companion devices are going to require additional energy due to added computational requirements. However, a gap in energy efficiency is quickly developing between the energy that can be delivered by today's battery technologies, and the energy needed to deliver all-day operation or 2-day always-on standby without a recharge. New innovations ranging from low-voltage digital and analog circuits, non-volatile memory, and adaptive power management, to energy harvesting, will be needed to further improve the battery life of these mobile companion devices. Increased bandwidth combined with decreased latency, higher power efficiency, energy harvesting, massive multimedia processing, and new interconnect technologies will all work together to revolutionize how we interact with our smart-companion devices. The implementation challenges in bringing these technologies to market may seem daunting and numerous at first, but with the strong collaboration in research and development from universities, government agencies, and corporations, the smart-mobile-companion devices of the future will likely become reality within 5 years!

  14. Personalized Recommendations Based on Users' Information-Centered Social Networks

    Science.gov (United States)

    Lee, Danielle

    2013-01-01

    The overwhelming amount of information available today makes it difficult for users to find useful information and as the solution to this information glut problem, recommendation technologies emerged. Among the several streams of related research, one important evolution in technology is to generate recommendations based on users' own social…

  15. Information Filtering via Clustering Coefficients of User-Object Bipartite Networks

    Science.gov (United States)

    Guo, Qiang; Leng, Rui; Shi, Kerui; Liu, Jian-Guo

    The clustering coefficient of user-object bipartite networks is presented to evaluate the overlap percentage of neighbors rating lists, which could be used to measure interest correlations among neighbor sets. The collaborative filtering (CF) information filtering algorithm evaluates a given user's interests in terms of his/her friends' opinions, which has become one of the most successful technologies for recommender systems. In this paper, different from the object clustering coefficient, users' clustering coefficients of user-object bipartite networks are introduced to improve the user similarity measurement. Numerical results for MovieLens and Netflix data sets show that users' clustering effects could enhance the algorithm performance. For MovieLens data set, the algorithmic accuracy, measured by the average ranking score, can be improved by 12.0% and the diversity could be improved by 18.2% and reach 0.649 when the recommendation list equals to 50. For Netflix data set, the accuracy could be improved by 14.5% at the optimal case and the popularity could be reduced by 13.4% comparing with the standard CF algorithm. Finally, we investigate the sparsity effect on the performance. This work indicates the user clustering coefficients is an effective factor to measure the user similarity, meanwhile statistical properties of user-object bipartite networks should be investigated to estimate users' tastes.

  16. Dynamic Trust Models between Users over Social Networks

    Science.gov (United States)

    2016-03-30

    the- art hTrust and its variants for solving the trust -link prediction problem. In addition to the above main research results, we developed a...AFRL-AFOSR-JP-TR-2016-0039 Dynamic Trust Models between Users over Social Networks Kazumi Saito University Of Shizuoka Final Report 04/05/2016...2013 to 30-03-2016 4. TITLE AND SUBTITLE (134042) Dynamic Trust Models between Users over Social Networks 5a. CONTRACT NUMBER FA2386-13-1

  17. Users Adaptation to Information and Communication Technology ...

    African Journals Online (AJOL)

    Users should endeavour to acquire skills in the use of electronic devices for effective utilization of ICT resources in FUTO library. There is the need for the improvement of ICT resources in FUTO Library to meet the needs and satisfaction of users. There is the need for the library to redefine its methods of strategic information ...

  18. Detection of mobile user location on next generation wireless networks

    DEFF Research Database (Denmark)

    Schou, Saowanee; Olesen, Henning

    2005-01-01

    of a Mobile IPv6 device can be determined by mapping the geographical location information with the two care-of-addresses and the physical address of the access point where the user is connected. Such a mechanism makes location services for mobile entities available on a global IP network. The end-users can...

  19. Technological tools for library user education: one library's experience.

    Science.gov (United States)

    Kerns, Stephanie C

    2007-01-01

    In today's world, library users are confronted with almost too many options for using information because of the ubiquitousness of technology. Yet, libraries can harness the power of the same technologies to help users find the information they need at the time it is needed. The tools described in this article represent a starting point for librarians looking for technologies that are easy to use, inexpensive, and have a reasonable learning curve. Technologies addressed include classroom technologies such as audience response systems and Web-based technologies, including Web tutorials and screencasting. These technologies enhance and offer flexibility and variety in many educational settings.

  20. Involving users in the development of embedded technology in construction

    DEFF Research Database (Denmark)

    Storgaard, Kresten; Buch-Hansen, Thomas Cornelius; Ærenlund, Lærke

    2011-01-01

    Based on a project about user driven innovation and embedded technology in construction (BIIB), the paper discusses methodological issues on user involvement. In the paper especially focus is on the experiences on involving users in collaborative development of scenarios, in the validation....... The second discussion on collaborative involvement, discuss experiences with methods for communication across cultural and professional competences with reference to boundary objects, tangible systems and visualization. In the project four segments of situations for use of embedded technology in construction...

  1. Semantic Technology Recommendation Based on the Analytic Network Process

    OpenAIRE

    Radulovic, F.; García-Castro, Raúl

    2012-01-01

    Semantic technologies have become widely adopted in recent years, and choosing the right technologies for the problems that users face is often a difficult task. This paper presents an application of the Analytic Network Process for the recommendation of semantic technologies, which is based on a quality model for semantic technologies. Instead of relying on expert-based comparisons of alternatives, the comparisons in our framework depend on real evaluation results. Furthermore, the recommend...

  2. Analysis of energy and control efficiencies of fuzzy logic and artificial neural network technologies in the heating energy supply system responding to the changes of user demands

    International Nuclear Information System (INIS)

    Ahn, Jonghoon; Cho, Soolyeon; Chung, Dae Hun

    2017-01-01

    Highlights: • Advanced controllers are proposed to reduce control errors and energy consumption increases. • The FIS and ANN models are utilized to compare conventional thermostat on/off controller. • To provide appropriate thermal energy, the models control the amount of air and its temperature simultaneously. • Control errors, heat gains, and output signals are compared to define models’ effectiveness. • The ANN model shows the best result for space heating responding to intermittent thermal changes. - Abstract: This paper presents hybrid control approaches for heating air supply in response to changes in demand by using the Fuzzy Inference System (FIS) and Artificial Neural Network (ANN) fitting models. Since early 2000’s, some advanced computing and statistical tools were introduced to replace conventional control models in improving control and energy efficiency. Among the tools, the FIS and ANN algorithms were used to define complex interactions between inputs and outputs, and were able to facilitate control models to predict or evaluate precise thermal performance. This paper introduces the FIS and ANN control schemes for simultaneously controlling the amount of supply air and its temperature. Input and output data derived from the FIS results generate and validate the ANN model, and both models are compared to the typical thermostat on/off baseline control to evaluate conditions of supply air for a heating season. The differences between the set-point and actual room temperature and their sums indicate control efficiency, and the heat gains into a room and their sums define the energy consumption level. This paper concludes that the simultaneous control of mass and temperature maintains the desired room temperature in a highly efficient manner. Sensitive controls may have a disadvantage in terms of energy consumption, but the ANN controller can minimize energy consumption in comparison with simple thermostat on/off controller. The results also

  3. Performance analysis of an opportunistic multi-user cognitive network with multiple primary users

    KAUST Repository

    Khan, Fahd Ahmed

    2014-03-01

    Consider a multi-user underlay cognitive network where multiple cognitive users concurrently share the spectrum with a primary network with multiple users. The channel between the secondary network is assumed to have independent but not identical Nakagami-m fading. The interference channel between the secondary users (SUs) and the primary users is assumed to have Rayleigh fading. A power allocation based on the instantaneous channel state information is derived when a peak interference power constraint is imposed on the secondary network in addition to the limited peak transmit power of each SU. The uplink scenario is considered where a single SU is selected for transmission. This opportunistic selection depends on the transmission channel power gain and the interference channel power gain as well as the power allocation policy adopted at the users. Exact closed form expressions for the moment-generating function, outage performance, symbol error rate performance, and the ergodic capacity are derived. Numerical results corroborate the derived analytical results. The performance is also studied in the asymptotic regimes, and the generalized diversity gain of this scheduling scheme is derived. It is shown that when the interference channel is deeply faded and the peak transmit power constraint is relaxed, the scheduling scheme achieves full diversity and that increasing the number of primary users does not impact the diversity order. © 2014 John Wiley & Sons, Ltd.

  4. Profiles of social networking sites users in the Netherlands

    NARCIS (Netherlands)

    Constantinides, Efthymios; Alarcón del Amo, Maria del Carmen; Lorenzo Romero, Carlota

    2010-01-01

    Online social networking has become a reality and integral part of the daily personal, social and business life. The extraordinary increase of the user numbers of Social Networking Sites (SNS) and the rampant creation of online communities presents businesses with many challenges and opportunities.

  5. Identifying influential user communities on the social network

    Science.gov (United States)

    Hu, Weishu; Gong, Zhiguo; Hou U, Leong; Guo, Jingzhi

    2015-10-01

    Nowadays social network services have been popularly used in electronic commerce systems. Users on the social network can develop different relationships based on their common interests and activities. In order to promote the business, it is interesting to explore hidden relationships among users developed on the social network. Such knowledge can be used to locate target users for different advertisements and to provide effective product recommendations. In this paper, we define and study a novel community detection problem that is to discover the hidden community structure in large social networks based on their common interests. We observe that the users typically pay more attention to those users who share similar interests, which enable a way to partition the users into different communities according to their common interests. We propose two algorithms to detect influential communities using common interests in large social networks efficiently and effectively. We conduct our experimental evaluation using a data set from Epinions, which demonstrates that our method achieves 4-11.8% accuracy improvement over the state-of-the-art method.

  6. Study on Strengthening Plan of Safety Network CCTV Monitoring by Steganography and User Authentication

    Directory of Open Access Journals (Sweden)

    Jung-oh Park

    2015-01-01

    Full Text Available Recently, as the utilization of CCTV (closed circuit television is emerging as an issue, the studies on CCTV are receiving much attention. Accordingly, due to the development of CCTV, CCTV has IP addresses and is connected to network; it is exposed to many threats on the existing web environment. In this paper, steganography is utilized to confirm the Data Masquerading and Data Modification and, in addition, to strengthen the security; the user information is protected based on PKI (public key infrastructure, SN (serial number, and R value (random number attributed at the time of login and the user authentication protocol to block nonauthorized access of malicious user in network CCTV environment was proposed. This paper should be appropriate for utilization of user infringement-related CCTV where user information protection-related technology is not applied for CCTV in the future.

  7. Global business networks and technology

    Directory of Open Access Journals (Sweden)

    Pomykalski Andrzej

    2015-05-01

    Full Text Available The current economic development changes the perception of technology innovation and business cooperation. Global business networks create very competitive markets characterised by constant innovation and dynamic changes. Further changes may come with growing involvement of active consumers and the development of Internet of Things. Focusing mainly on activities of multinational business networks operating in Poland the author describes selected aspects of gradual adoption of innovation management concepts in firms. The article provides with an overview of concepts described in innovation management literature during the last decade and of new concepts evolving.

  8. An X window based graphics user interface for radiation information processing system developed with object-oriented programming technology

    International Nuclear Information System (INIS)

    Gao Wenhuan; Fu Changqing; Kang Kejun

    1993-01-01

    X Window is a network-oriented and network transparent windowing system, and now dominant in the Unix domain. The object-oriented programming technology can be used to change the extensibility of a software system remarkably. An introduction to graphics user interface is given. And how to develop a graphics user interface for radiation information processing system with object-oriented programming technology, which is based on X Window and independent of application is described briefly

  9. The Visual Web User Interface Design in Augmented Reality Technology

    OpenAIRE

    Chouyin Hsu; Haui-Chih Shiau

    2013-01-01

    Upon the popularity of 3C devices, the visual creatures are all around us, such the online game, touch pad, video and animation. Therefore, the text-based web page will no longer satisfy users. With the popularity of webcam, digital camera, stereoscopic glasses, or head-mounted display, the user interface becomes more visual and multi-dimensional. For the consideration of 3D and visual display in the research of web user interface design, Augmented Reality technology providing the convenient ...

  10. Towards a new Role of Agent Technology in User Modelling

    OpenAIRE

    Lorenz, A.

    2003-01-01

    This paper discusses resent attempts to employ multi-agent technologies for user modelling purposes. Based on the analysis of recent implemented systems, this contribution provides a general agent definition representing a flexible implementation to employ highly specialized entities for user modelling tasks, and illustrates communication and cooperation approaches. In the overall solution, agent teams cooperate to fulfill the requirements of user modelling in a more appropriate way.

  11. CCTV networking and digital technology

    CERN Document Server

    Damjanovski, Vlado

    2005-01-01

    Closed circuit television (CCTV) is experiencing a leap in technology using digital techniques, networking and the Internet. The new edition of this high-level professional reference retains the particulars that made the first edition a success, including the details of CCD cameras, lenses, coaxial cables, fiber-optics, and system design, but it is expanded to cover all video compression techniques used in the ever increasing assortment of digital video recorders (DVRs) available on the market today. This new edition of the book CCTV demystifies DVR technology. It also serves to clarify the te

  12. User-centered Technologies For Blind Children

    OpenAIRE

    Jaime Sánchez

    2008-01-01

    The purpose of this paper is to review, summarize, and illustrate research work involving four audio-based games created within a user-centered design methodology through successive usability tasks and evaluations. These games were designed by considering the mental model of blind children and their styles of interaction to perceive and process data and information. The goal of these games was to enhance the cognitive development of spatial structures, memory, haptic perception, mathe...

  13. Graphical user interface for wireless sensor networks simulator

    Science.gov (United States)

    Paczesny, Tomasz; Paczesny, Daniel; Weremczuk, Jerzy

    2008-01-01

    Wireless Sensor Networks (WSN) are currently very popular area of development. It can be suited in many applications form military through environment monitoring, healthcare, home automation and others. Those networks, when working in dynamic, ad-hoc model, need effective protocols which must differ from common computer networks algorithms. Research on those protocols would be difficult without simulation tool, because real applications often use many nodes and tests on such a big networks take much effort and costs. The paper presents Graphical User Interface (GUI) for simulator which is dedicated for WSN studies, especially in routing and data link protocols evaluation.

  14. Mobility-Aware User Association in Uplink Cellular Networks

    KAUST Repository

    Arshad, Rabe

    2017-07-20

    This letter studies the mobility aware user-to-BS association policies, within a stochastic geometry framework, in two tier uplink cellular networks with fractional channel inversion power control. Particularly, we model the base stations’ locations using the widely accepted poisson point process and obtain the coverage probability and handover cost expressions for the coupled and decoupled uplink and downlink associations. To this end, we compute the average throughput for the mobile users and study the merits and demerits of each association strategy.

  15. Building secure network by integrated technology

    International Nuclear Information System (INIS)

    An Dehai; Xu Rongsheng; Liu Baoxu

    2000-01-01

    The author introduces a method which can realize the most powerful network security prevention by the network security integrated technologies such as firewall, realtime monitor, network scanner, Web detection and security, etc

  16. The Role of Electronic Learning Technology in Networks Systems

    International Nuclear Information System (INIS)

    Abd ELhamid, A.; Ayad, N.M.A.; Fouad, Y.; Abdelkader, T.

    2016-01-01

    Recently, Electronic Learning Technology (ELT) has been widely spread as one of the new technologies in the world through using Information and Communication Technology (ICT). One of the strategies of ELT is Simulation, for instance Military and Medical simulations that are used to avoid risks and reduce Costs. A wireless communication network refers to any network not physically connected by cables, which enables the desired convenience and mobility for the user. Wireless communication networks have been useful in areas such as commerce, education and defense. According to the nature of a particular application, they can be used in home-based and industrial systems or in commercial and military environments. Historically, Mobile Ad-hoc Networks (MANET) have primarily been used for tactical military network related applications to improve battlefield communications/ survivability. MANET is a collection of wireless nodes that can dynamically be set up anywhere and anytime without using any pre-existing network infrastructure. Mobility in wireless networks basically refers to nodes changing its point of attachment to the network. Also, how the end terminals can move, there are many mobility models described the movement of nodes, many researchers use the Random Way point Mobility Model (RWPM). In this paper, a Graphical User Interface (GUI) for RWPM simulation is introduced as a proposal to be used through ELT Project. In the research area of computer and communications networks, simulation is a very useful technique for the behavior of networks

  17. INTERMEDIARIES, USERS AND SOCIAL LEARNING IN TECHNOLOGICAL INNOVATION

    OpenAIRE

    JAMES STEWART; SAMPSA HYYSALO

    2008-01-01

    This paper explores the role of intermediaries in the development and appropriation of new technologies. We focus on intermediaries that facilitate user innovation, and the linking of user innovation into supply side activities. We review findings on intermediaries in some of our studies and other available literature to build a framework to explore of how intermediaries work in making innovation happen. We make sense of these processes by taking a long-term view of the dynamics of technology...

  18. User cooperation, virality and gaming in a social mobile network

    DEFF Research Database (Denmark)

    Varga, C; Blazovics, L; Charaf, H

    2012-01-01

    Social networks and mobile systems are both rapidly developing areas nowadays. In this chapter, we will introduce Gedda-Headz, a novel social mobile gaming concept that brings these two areas together. Gedda-Headz is a social mobile network that mainly focuses on multiplayer mobile gaming. First we...... will thoroughly discuss how users may cooperate with each other in Gedda-Headz, as cooperation is very important in a mobile environment. Among other benefits, it may help users to use services that would otherwise be unreachable for them, or greatly decrease the energy cost of certain activities. Finally...

  19. Distributed User Selection in Network MIMO Systems with Limited Feedback

    KAUST Repository

    Elkhalil, Khalil

    2015-09-06

    We propose a distributed user selection strategy in a network MIMO setting with M base stations serving K users. Each base station is equipped with L antennas, where LM ≪ K. The conventional selection strategy is based on a well known technique called semi-orthogonal user selection when the zero-forcing beamforming (ZFBF) is adopted. Such technique, however, requires perfect channel state information at the transmitter (CSIT), which might not be available or need large feedback overhead. This paper proposes an alternative distributed user selection technique where each user sets a timer that is inversely proportional to his channel quality indicator (CQI), as a means to reduce the feedback overhead. The proposed strategy allows only the user with the highest CQI to respond with a feedback. Such technique, however, remains collision free only if the transmission time is shorter than the difference between the strongest user timer and the second strongest user timer. To overcome the situation of longer transmission times, the paper proposes another feedback strategy that is based on the theory of compressive sensing, where collision is allowed and all users encode their feedback information and send it back to the base-stations simultaneously. The paper shows that the problem can be formulated as a block sparse recovery problem which is agnostic on the transmission time, which makes it a good alternative to the timer approach when collision is dominant.

  20. A Survey of Users' Reactions to the Local Area Network in the Library School at the University of North Texas. A Research Study.

    Science.gov (United States)

    Brazile, Orella Ramsey

    Research analyzing users' reactions to the implementation of automation and computer technology in the industrial and business fields indicates that users will respond more positively to these new technologies if they are adequately trained beforehand. To measure response in the academic sector, users' reactions to the local area network (LAN) in…

  1. 12th European VLBI Network Symposium and Users Meeting

    Science.gov (United States)

    Tarchi, Andrea; Giroletti, Marcello; Feretti, Luigina

    The Istituto di Radioastronomia (IRA) di Bologna and the Osservatorio Astronomico di Cagliari (OAC), on behalf of the European VLBI Consortium, hosted the 12th European VLBI Network (EVN) Symposium and Users Meeting. The Conference was held from 7th to 10th of October at the Hotel Regina Margherita, in the center of Cagliari. The latest scientific results and technical developments from VLBI, and, in particular, e-VLBI and space-VLBI (RadioAstron) outcomes were reported. The timing of this meeting coincided with the first successful observational tests of the Sardinia Radio Telescopes within the EVN, and with a number of results from new and upgraded radio facilities around the globe, such as e-MERLIN, ALMA, and the SKA pathfinders. The symposium was attended by 133 participants from all over the world, with the Asian community represented by more than 20 colleagues. The program of the meeting consisted of 70 oral contributions (including 8 invited speakers) and 50 poster that covered a very wide range of VLBI topics both in galactic and extragalactic astrophysics (e.g., AGN, stellar evolution from birth to death, astrometry, and planetary science) as well as technological developments and future international collaborations. The scientific program also included a visit to the 64-m Sardinia Radio Telescope (SRT) and the EVN Users Meeting, where astronomers have provided useful feedback on various matters regarding EVN operations. The research leading to these results has received funding from the European Commission Seventh Framework Programme (FP/2007-2013) under grant agreement No 283393 (RadioNet3). EDITORIAL BOARD: Andrea Tarchi, Marcello Giroletti, Luigina Feretti

  2. Social networking sites and older users - a systematic review.

    Science.gov (United States)

    Nef, Tobias; Ganea, Raluca L; Müri, René M; Mosimann, Urs P

    2013-07-01

    Social networking sites can be beneficial for senior citizens to promote social participation and to enhance intergenerational communication. Particularly for older adults with impaired mobility, social networking sites can help them to connect with family members and other active social networking users. The aim of this systematic review is to give an overview of existing scientific literature on social networking in older users. Computerized databases were searched and 105 articles were identified and screened using exclusion criteria. After exclusion of 87 articles, 18 articles were included, reviewed, classified, and the key findings were extracted. Common findings are identified and critically discussed and possible future research directions are outlined. The main benefit of using social networking sites for older adults is to enter in an intergenerational communication with younger family members (children and grandchildren) that is appreciated by both sides. Identified barriers are privacy concerns, technical difficulties and the fact that current Web design does not take the needs of older users into account. Under the conditions that these problems are carefully addressed, social networking sites have the potential to support today's and tomorrow's communication between older and younger family members.

  3. User-Centered Design and Interactive Health Technologies for Patients

    Science.gov (United States)

    De Vito Dabbs, Annette; Myers, Brad A.; Mc Curry, Kenneth R.; Dunbar-Jacob, Jacqueline; Hawkins, Robert P.; Begey, Alex; Dew, Mary Amanda

    2010-01-01

    Despite recommendations that patients be involved in the design and testing of health technologies, few reports describe how to involve patients in systematic and meaningful ways to ensure that applications are customized to meet their needs. User-centered design (UCD) is an approach that involves end-users throughout the development process so that technology support tasks, are easy to operate, and are of value to users. In this paper we provide an overview of UCD and use the development of Pocket Personal Assistant for Tracking Health (Pocket PATH), to illustrate how these principles and techniques were applied to involve patients in the development of this interactive health technology. Involving patient-users in the design and testing ensured functionality and usability, therefore increasing the likelihood of promoting the intended health outcomes. PMID:19411947

  4. User recommendation in healthcare social media by assessing user similarity in heterogeneous network.

    Science.gov (United States)

    Jiang, Ling; Yang, Christopher C

    2017-09-01

    The rapid growth of online health social websites has captured a vast amount of healthcare information and made the information easy to access for health consumers. E-patients often use these social websites for informational and emotional support. However, health consumers could be easily overwhelmed by the overloaded information. Healthcare information searching can be very difficult for consumers, not to mention most of them are not skilled information searcher. In this work, we investigate the approaches for measuring user similarity in online health social websites. By recommending similar users to consumers, we can help them to seek informational and emotional support in a more efficient way. We propose to represent the healthcare social media data as a heterogeneous healthcare information network and introduce the local and global structural approaches for measuring user similarity in a heterogeneous network. We compare the proposed structural approaches with the content-based approach. Experiments were conducted on a dataset collected from a popular online health social website, and the results showed that content-based approach performed better for inactive users, while structural approaches performed better for active users. Moreover, global structural approach outperformed local structural approach for all user groups. In addition, we conducted experiments on local and global structural approaches using different weight schemas for the edges in the network. Leverage performed the best for both local and global approaches. Finally, we integrated different approaches and demonstrated that hybrid method yielded better performance than the individual approach. The results indicate that content-based methods can effectively capture the similarity of inactive users who usually have focused interests, while structural methods can achieve better performance when rich structural information is available. Local structural approach only considers direct connections

  5. Fraud Detection In Mobile Communications Networks Using User ...

    African Journals Online (AJOL)

    The call data is used in describing behavioural patterns of users. Neural networks and probabilistic models are employed in learning these usage patterns from call data by detecting changes in established usage patterns or to recognize typical usage patterns of fraud. The methods are shown to be effective in detecting ...

  6. Competitive diffusion in online social networks with heterogeneous users

    Science.gov (United States)

    Li, Pei; He, Su; Wang, Hui; Zhang, Xin

    2014-06-01

    Online social networks have attracted increasing attention since they provide various approaches for hundreds of millions of people to stay connected with their friends. However, most research on diffusion dynamics in epidemiology cannot be applied directly to characterize online social networks, where users are heterogeneous and may act differently according to their standpoints. In this paper, we propose models to characterize the competitive diffusion in online social networks with heterogeneous users. We classify messages into two types (i.e., positive and negative) and users into three types (i.e., positive, negative and neutral). We estimate the positive (negative) influence for a user generating a given type message, which is the number of times that positive (negative) messages are processed (i.e., read) incurred by this action. We then consider the diffusion threshold, above which the corresponding influence will approach infinity, and the effect threshold, above which the unexpected influence of generating a message will exceed the expected one. We verify all these results by simulations, which show the analysis results are perfectly consistent with the simulation results. These results are of importance in understanding the diffusion dynamics in online social networks, and also critical for advertisers in viral marketing where there are fans, haters and neutrals.

  7. Technological Developments in Networking, Education and Automation

    CERN Document Server

    Elleithy, Khaled; Iskander, Magued; Kapila, Vikram; Karim, Mohammad A; Mahmood, Ausif

    2010-01-01

    "Technological Developments in Networking, Education and Automation" includes a set of rigorously reviewed world-class manuscripts addressing and detailing state-of-the-art research projects in the following areas: Computer Networks: Access Technologies, Medium Access Control, Network architectures and Equipment, Optical Networks and Switching, Telecommunication Technology, and Ultra Wideband Communications. Engineering Education and Online Learning: including development of courses and systems for engineering, technical and liberal studies programs; online laboratories; intelligent

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

    DEFF Research Database (Denmark)

    Hillmann, Robert; Trier, Matthias

    2012-01-01

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

  9. User Characteristics、User Involvement and Technology Acceptance in Library Automation System Usage

    Directory of Open Access Journals (Sweden)

    Piching Chu

    2002-12-01

    Full Text Available This paper looks into the relationship of user characteristics, user involvement and technology acceptance, also try to find the relationship of the above three variables and library automation system usage. By interview and questionnaire study, the results are described, according to the analysis of the relative literature and the main conclusions, the researcher offers some suggestions for improving the system usage.[Article content in Chinese

  10. Networking Technologies and the Rate of Technological Change

    Directory of Open Access Journals (Sweden)

    Charles Mitchell

    2005-12-01

    Full Text Available Network technology is changing rapidly and those adept at ICT analysis need resolve rate of change issues. Developments in networking now are in the direction of heuristic intelligence. Since about 1980, networking techniques have encouraged combining bits of information with imagination cognitively to improve ideas about reality. ICT enterprise projects utilize networking to sustain requisite imagination. Assumptions and misassuptions of project builders are rationally comprehended as networking sustains creative processes. The monopolization of valuable network techniques influences in the direction of esoteric networking. Data presents that substantial knowledge and networking is now occurring globally. As a netaphor, networking

  11. Stimulant use among African American and Latino MSM social networking users.

    Science.gov (United States)

    Young, Sean D; Shoptaw, Steve

    2013-01-01

    High stimulant-using and at-risk HIV populations, such as African American and Latino men who have sex with men (MSM), are increasingly using social networking technologies. However, no known research has explored associations between stimulant use, sexual risk behaviors, and social networking among these populations. Participants were recruited using the Facebook Connect software application, which narrowed the sample to 118 (primarily African American and Latino MSM) active Facebook users. Participants completed demographic, Internet and social media use, and drug use survey items. Participants reported high rates of cocaine and methamphetamine use (both more than 15% within the past 12 months). More than 70% of participants reported using social networking technologies to meet people, and more than 30% used them to find sexual partners. A multivariate logistic regression showed that (1) participants using social networks to find sexual partners were more likely to have used methamphetamines within the past 12 months and (2) those who were more comfortable talking online compared to face-to-face had over 4 times the odds of methamphetamine use and over 6 times the odds of cocaine use within the past 12 months. Minority MSM who used social networks to meet men and find sexual partners had high risk for stimulant use. Understanding drug use among minority social networking users will provide insights to incorporate these technologies into drug prevention interventions.

  12. User-Adapted Recommendation of Content on Mobile Devices Using Bayesian Networks

    Science.gov (United States)

    Iwasaki, Hirotoshi; Mizuno, Nobuhiro; Hara, Kousuke; Motomura, Yoichi

    Mobile devices, such as cellular phones and car navigation systems, are essential to daily life. People acquire necessary information and preferred content over communication networks anywhere, anytime. However, usability issues arise from the simplicity of user interfaces themselves. Thus, a recommendation of content that is adapted to a user's preference and situation will help the user select content. In this paper, we describe a method to realize such a system using Bayesian networks. This user-adapted mobile system is based on a user model that provides recommendation of content (i.e., restaurants, shops, and music that are suitable to the user and situation) and that learns incrementally based on accumulated usage history data. However, sufficient samples are not always guaranteed, since a user model would require combined dependency among users, situations, and contents. Therefore, we propose the LK method for modeling, which complements incomplete and insufficient samples using knowledge data, and CPT incremental learning for adaptation based on a small number of samples. In order to evaluate the methods proposed, we applied them to restaurant recommendations made on car navigation systems. The evaluation results confirmed that our model based on the LK method can be expected to provide better generalization performance than that of the conventional method. Furthermore, our system would require much less operation than current car navigation systems from the beginning of use. Our evaluation results also indicate that learning a user's individual preference through CPT incremental learning would be beneficial to many users, even with only a few samples. As a result, we have developed the technology of a system that becomes more adapted to a user the more it is used.

  13. Evaluating innovation networks in emerging technologies

    NARCIS (Netherlands)

    Valk, T. van der; Chappin, M.M.H.; Gijsbers, G.W.

    2011-01-01

    Interorganisational innovation networks are increasingly important for innovation in emerging technology fields. The performance of such networks can have a large impact on the future development of emerging technologies. A useful framework for the evaluation of innovation networks however does not

  14. Mobile Phones as Technological Companions : Users' Perspectives and Experiences

    OpenAIRE

    Allemo, Erik

    2009-01-01

    The applicability of the term technological companion on mobile phones has been investigated with focus group sessions with mobile phone users in Uppsala, Sweden. A definition of a companion with features like, friendliness, long time proximity, information handling was conceived. With the help of this definition the applicability was then tried with the help of data gathered during the focus group sessions. The study shows that users rarely turn off their phones and that the phones accompany...

  15. Technologies for convergence in the metro network

    Science.gov (United States)

    Frankel, Michael Y.

    2005-02-01

    Traditional metro network architectures comprise multiple layers of networking equipment supporting a wide array of services and packet-oriented applications. Among others, these include WDM, SDH, ATM, Ethernet and IP, each requiring its own network elements and associated management solutions to perform its own independent networking functions. While these work well individually, the combined network is cumbersome and inefficient. Recent advancements in network technologies are now changing the way metro networks are designed. Multi-functional consolidation through technology integration and the standardization of protocol inter-networking methods are leading to a converged network solution in support of a diverse set of packet-aware service offerings. This presentation will explore new technologies that are enabling convergence in the metro network, both across layers and across services.

  16. Combination of Bayesian Network and Overlay Model in User Modeling

    Directory of Open Access Journals (Sweden)

    Loc Nguyen

    2009-12-01

    Full Text Available The core of adaptive system is user model containing personal information such as knowledge, learning styles, goals… which is requisite for learning personalized process. There are many modeling approaches, for example: stereotype, overlay, plan recognition… but they don’t bring out the solid method for reasoning from user model. This paper introduces the statistical method that combines Bayesian network and overlay modeling so that it is able to infer user’s knowledge from evidences collected during user’s learning process.

  17. Secure and Efficient Two-Factor User Authentication Scheme with User Anonymity for Network Based E-Health Care Applications.

    Science.gov (United States)

    Li, Xiong; Niu, Jianwei; Karuppiah, Marimuthu; Kumari, Saru; Wu, Fan

    2016-12-01

    Benefited from the development of network and communication technologies, E-health care systems and telemedicine have got the fast development. By using the E-health care systems, patient can enjoy the remote medical service provided by the medical server. Medical data are important privacy information for patient, so it is an important issue to ensure the secure of transmitted medical data through public network. Authentication scheme can thwart unauthorized users from accessing services via insecure network environments, so user authentication with privacy protection is an important mechanism for the security of E-health care systems. Recently, based on three factors (password, biometric and smart card), an user authentication scheme for E-health care systems was been proposed by Amin et al., and they claimed that their scheme can withstand most of common attacks. Unfortunate, we find that their scheme cannot achieve the untraceability feature of the patient. Besides, their scheme lacks a password check mechanism such that it is inefficient to find the unauthorized login by the mistake of input a wrong password. Due to the same reason, their scheme is vulnerable to Denial of Service (DoS) attack if the patient updates the password mistakenly by using a wrong password. In order improve the security level of authentication scheme for E-health care application, a robust user authentication scheme with privacy protection is proposed for E-health care systems. Then, security prove of our scheme are analysed. Security and performance analyses show that our scheme is more powerful and secure for E-health care systems when compared with other related schemes.

  18. Survey of network and information security technology

    International Nuclear Information System (INIS)

    Liu Baoxu; Wang Xiaozhen

    2007-01-01

    With the rapidly development of the computer network technology and informationize working of our Country, Network and Information Security issues becomes the focal point problem that people shows solicitude for. On the basis analysing security threat and challenge of network information and their developing trend. This paper briefly analyses and discusses the main relatively study direction and content about the theory, technology and practice of Network and Information Security. (authors)

  19. Delegation Based User Authentication Framework over Cognitive Radio Networks

    Directory of Open Access Journals (Sweden)

    Hyunsung Kim

    2017-12-01

    Full Text Available To address the ever increasing demand for wireless bandwidth, cognitive radio networks (CRNs have been proposed to improve the efficiency of channel utilization. CRN permits unlicensed users to utilize the idle spectrum as long as it does not introduce interference to the primary users due to the Federal Communications Commission’s recent regulatory policies. In this paper, we first identify some required distinctive security and privacy features for CRNs focused on ECMA-392, which is the first industrial standard for personal or portable devices in the television white spaces. After that, we propose a delegation based user authentication framework as a basic security and privacy module with full consideration of the required features over CRNs. The proposed framework provides privacy preserving yet accountable security within the CRN entities. Security and privacy analyses show that the proposed framework supports unlinkability, context privacy, anonymity, no registration and conditional traceability, which are the required security and privacy aspects in CRNs.

  20. Technology Benefit Estimator (T/BEST): User's manual

    Science.gov (United States)

    Generazio, Edward R.; Chamis, Christos C.; Abumeri, Galib

    1994-12-01

    The Technology Benefit Estimator (T/BEST) system is a formal method to assess advanced technologies and quantify the benefit contributions for prioritization. T/BEST may be used to provide guidelines to identify and prioritize high payoff research areas, help manage research and limited resources, show the link between advanced concepts and the bottom line, i.e., accrued benefit and value, and to communicate credibly the benefits of research. The T/BEST software computer program is specifically designed to estimating benefits, and benefit sensitivities, of introducing new technologies into existing propulsion systems. Key engine cycle, structural, fluid, mission and cost analysis modules are used to provide a framework for interfacing with advanced technologies. An open-ended, modular approach is used to allow for modification and addition of both key and advanced technology modules. T/BEST has a hierarchical framework that yields varying levels of benefit estimation accuracy that are dependent on the degree of input detail available. This hierarchical feature permits rapid estimation of technology benefits even when the technology is at the conceptual stage. As knowledge of the technology details increases the accuracy of the benefit analysis increases. Included in T/BEST's framework are correlations developed from a statistical data base that is relied upon if there is insufficient information given in a particular area, e.g., fuel capacity or aircraft landing weight. Statistical predictions are not required if these data are specified in the mission requirements. The engine cycle, structural fluid, cost, noise, and emissions analyses interact with the default or user material and component libraries to yield estimates of specific global benefits: range, speed, thrust, capacity, component life, noise, emissions, specific fuel consumption, component and engine weights, pre-certification test, mission performance engine cost, direct operating cost, life cycle cost

  1. Networked Intimacy. Intimacy and Friendship among Italian Facebook users

    OpenAIRE

    Farci, Manolo; Rossi, Luca; Boccia Artieri, Giovanni; Giglietto, Fabio

    2016-01-01

    In this paper, we describe the results of a qualitative study conducted with 120 Italian Facebook users to investigate how Facebook enables people to achieve a mutually constitutive intimacy with their own friendship network: a negotiation of intimacy in public through self-disclosure, where the affordances of the platform are useful to elicit significant reactions, validations and demonstrations of affection from others. We observed that, in order to achieve various levels of intimacy on Fac...

  2. Space Station Freedom technology payload user operations facility concept

    Science.gov (United States)

    Henning, Gary N.; Avery, Don E.

    1992-01-01

    This report presents a concept for a User Operations Facility (UOF) for payloads sponsored by the NASA Office of Aeronautics and Space Technology (OAST). The UOF can be located at any OAST sponsored center; however, for planning purposes, it is assumed that the center will be located at Langley Research Center (LaRC).

  3. Multilabel user classification using the community structure of online networks.

    Science.gov (United States)

    Rizos, Georgios; Papadopoulos, Symeon; Kompatsiaris, Yiannis

    2017-01-01

    We study the problem of semi-supervised, multi-label user classification of networked data in the online social platform setting. We propose a framework that combines unsupervised community extraction and supervised, community-based feature weighting before training a classifier. We introduce Approximate Regularized Commute-Time Embedding (ARCTE), an algorithm that projects the users of a social graph onto a latent space, but instead of packing the global structure into a matrix of predefined rank, as many spectral and neural representation learning methods do, it extracts local communities for all users in the graph in order to learn a sparse embedding. To this end, we employ an improvement of personalized PageRank algorithms for searching locally in each user's graph structure. Then, we perform supervised community feature weighting in order to boost the importance of highly predictive communities. We assess our method performance on the problem of user classification by performing an extensive comparative study among various recent methods based on graph embeddings. The comparison shows that ARCTE significantly outperforms the competition in almost all cases, achieving up to 35% relative improvement compared to the second best competing method in terms of F1-score.

  4. Multilabel user classification using the community structure of online networks.

    Directory of Open Access Journals (Sweden)

    Georgios Rizos

    Full Text Available We study the problem of semi-supervised, multi-label user classification of networked data in the online social platform setting. We propose a framework that combines unsupervised community extraction and supervised, community-based feature weighting before training a classifier. We introduce Approximate Regularized Commute-Time Embedding (ARCTE, an algorithm that projects the users of a social graph onto a latent space, but instead of packing the global structure into a matrix of predefined rank, as many spectral and neural representation learning methods do, it extracts local communities for all users in the graph in order to learn a sparse embedding. To this end, we employ an improvement of personalized PageRank algorithms for searching locally in each user's graph structure. Then, we perform supervised community feature weighting in order to boost the importance of highly predictive communities. We assess our method performance on the problem of user classification by performing an extensive comparative study among various recent methods based on graph embeddings. The comparison shows that ARCTE significantly outperforms the competition in almost all cases, achieving up to 35% relative improvement compared to the second best competing method in terms of F1-score.

  5. Imagining value, imagining users: academic technology transfer for health innovation.

    Science.gov (United States)

    Miller, Fiona Alice; Sanders, Carrie B; Lehoux, Pascale

    2009-04-01

    Governments have invested heavily in the clinical and economic promise of health innovation and express increasing concern with the efficacy and efficiency of the health innovation system. In considering strategies for 'better' health innovation, policy makers and researchers have taken a particular interest in the work of universities and related public research organizations: How do these organizations identify and transfer promising innovations to market, and do these efforts make best use of public sector investments? We conducted an ethnographic study of technology transfer offices (TTOs) in Ontario and British Columbia, Canada, to consider the place of health and health system imperatives in judgments of value in early-stage health innovation. Our analysis suggests that the valuation process is poorly specified as a set of task-specific judgments. Instead, we argue that technology transfer professionals are active participants in the construction of the innovation and assign value by 'imagining' the end product in its 'context of use'. Oriented as they are to the commercialization of health technology, TTOs understand users primarily as market players. The immediate users of TTOs' efforts are commercial partners (i.e., licensees, investors) who are capable of translating current discoveries into future commodities. The ultimate end users - patients, clinicians, health systems - are the future consumers of the products to be sold. Attention to these proximate and more distal users in the valuation process is a complex and constitutive feature of the work of health technology transfer. At the same time, judgements about individual technologies are made in relation to a broader imperative through which TTOs seek to imagine and construct sustainable innovation systems. Judgments of value are rendered sensible in relation to the logic of valuation for systems of innovation that, in turn, configure users of health innovation in systemic ways.

  6. Script of Healthcare Technology: Do Designs of Robotic Beds Exclude or Include Users?

    DEFF Research Database (Denmark)

    Brodersen, Søsser Grith Kragh; Hansen, Meiken; Lindegaard, Hanne

    2015-01-01

    of assistive technologies as design of socio-material assemblies , which include an analysis of the products already used in relation to multiple users, their practices and wishes. In the article we focus on the challenges in the implementation of two types of robotic beds used for disability care...... in a municipality in Denmark. We follow both the caregivers and disabled people’s daily practices. By using Actor Network Theory we explore the socio-material settings and the design challenges. The theoretical concept of ‘script’ is used to investigate how the artifacts (beds) and the multiple users go through...

  7. User-Friendly Establishment of Trust in Distributed Home Automation Networks

    DEFF Research Database (Denmark)

    Hjorth, Theis S.; Torbensen, Rune; Madsen, Per Printz

    2014-01-01

    Current wireless technologies use a variety of methods to locally exchange and verify credentials between devices to establish trusted relationships. Scenarios in home automation networks also require this capability over the Internet, but the necessary involvement of non-expert users to setup...... these relationships can lead to misconfiguration or breaches of security. We outline a security system for Home Automation called Trusted Domain that can establish and maintain cryptographically secure relationships between devices connected via IP-based networks and the Internet. Trust establishment is presented...

  8. Determinant of SPAN’s User Performance: Technology Performance Chain

    Directory of Open Access Journals (Sweden)

    Ratna Asih Wulandari

    2017-08-01

    Full Text Available Integrated Financial Management Information System (IFMIS is designed to improve accountability, transparency, and efficiency of the government financial management. The core of IFMIS in Indonesia is SPAN (Sistem Perbendaharaan dan Anggaran Negara. SPAN plays main role in organization process. SPAN supports job completion as well. This research links information system (SPAN and individual performance. This study investigates the relationship among technology characteristics, task characteristics, computer self efficacy (CSE, task technology fit (TTF and utilization toward SPAN’s user performance. This is a causal explanatory research. Questionnaires were distributed to SPAN’s users in Lombok Island and analyzed by partial least square (Smart PLS. Analytical results show that technology characteristics and task characteristics have positive influences to TTF and TTF has positive influence of utilization.

  9. End-User Evaluations of Semantic Web Technologies

    Energy Technology Data Exchange (ETDEWEB)

    McCool, Rob; Cowell, Andrew J.; Thurman, David A.

    2005-11-07

    Stanford University's Knowledge Systems Laboratory (KSL) is working in partnership with Battelle Memorial Institute and IBM Watson Research Center to develop a suite of technologies for information extraction, knowledge representation & reasoning, and human-information interaction, in unison entitled 'Knowledge Associates for Novel Intelligence' (KANI). We have developed an integrated analytic environment composed of a collection of analyst associates, software components that aid the user at different stages of the information analysis process. An important part of our participatory design process has been to ensure our technologies and designs are tightly integrate with the needs and requirements of our end users, To this end, we perform a sequence of evaluations towards the end of the development process that ensure the technologies are both functional and usable. This paper reports on that process.

  10. Technology report on Railway Embedded Network solutions

    OpenAIRE

    WAHL, M; BERNOCCHI, M; JUST, P; WEISS, AH; GOIKOETXEA, J; BILLION, J; NEMORIN, J

    2007-01-01

    Deliverable D3D.3.1 Technology report on Railway Embedded Network solutions is a deliverable of Work Package SP3D_WP3 ICOM Specification & Telecom Interfaces of Onboard and Train Train Networks. It takes place within the InteGRail Task 3D_03.1 State of the Art in Embedded Networks. The objectives of this deliverable are: - to consider which embedded communication network technologies are already into ser-vice within the trains; - to analyse Ethernet-based technologies; - to evaluate how Ethe...

  11. A User Centered Approach to Developing Emergent Technology Products

    DEFF Research Database (Denmark)

    Restrepo-Giraldo, John Dairo; McAloone, Timothy Charles; Schlegel, Tanja

    2008-01-01

    Current participatory design methods do not allow designers to gain the insight required to develop products with emerging technologies, that is, products that do not have any precedents in the users’ knowledge base and experience. This poses challenges to the designers, as input from users cannot...... was to identify the main form factor drivers for the design of such a phone. Five possible usage scenarios were identified and five form factors were derived from testing these scenarios, which were subsequently evaluated by potential users, through highly focused feedback sessions. The paper also discusses some...

  12. Walking on a user similarity network towards personalized recommendations.

    Directory of Open Access Journals (Sweden)

    Mingxin Gan

    Full Text Available Personalized recommender systems have been receiving more and more attention in addressing the serious problem of information overload accompanying the rapid evolution of the world-wide-web. Although traditional collaborative filtering approaches based on similarities between users have achieved remarkable success, it has been shown that the existence of popular objects may adversely influence the correct scoring of candidate objects, which lead to unreasonable recommendation results. Meanwhile, recent advances have demonstrated that approaches based on diffusion and random walk processes exhibit superior performance over collaborative filtering methods in both the recommendation accuracy and diversity. Building on these results, we adopt three strategies (power-law adjustment, nearest neighbor, and threshold filtration to adjust a user similarity network from user similarity scores calculated on historical data, and then propose a random walk with restart model on the constructed network to achieve personalized recommendations. We perform cross-validation experiments on two real data sets (MovieLens and Netflix and compare the performance of our method against the existing state-of-the-art methods. Results show that our method outperforms existing methods in not only recommendation accuracy and diversity, but also retrieval performance.

  13. Walking on a user similarity network towards personalized recommendations.

    Science.gov (United States)

    Gan, Mingxin

    2014-01-01

    Personalized recommender systems have been receiving more and more attention in addressing the serious problem of information overload accompanying the rapid evolution of the world-wide-web. Although traditional collaborative filtering approaches based on similarities between users have achieved remarkable success, it has been shown that the existence of popular objects may adversely influence the correct scoring of candidate objects, which lead to unreasonable recommendation results. Meanwhile, recent advances have demonstrated that approaches based on diffusion and random walk processes exhibit superior performance over collaborative filtering methods in both the recommendation accuracy and diversity. Building on these results, we adopt three strategies (power-law adjustment, nearest neighbor, and threshold filtration) to adjust a user similarity network from user similarity scores calculated on historical data, and then propose a random walk with restart model on the constructed network to achieve personalized recommendations. We perform cross-validation experiments on two real data sets (MovieLens and Netflix) and compare the performance of our method against the existing state-of-the-art methods. Results show that our method outperforms existing methods in not only recommendation accuracy and diversity, but also retrieval performance.

  14. Development of Beam Utilization Technologies and Support for Users

    International Nuclear Information System (INIS)

    Kim, Kyeryung; Jung, Myunghwan; Noh, Yongoh; Lee, Sooyeon; Kim, Hyukwook; Kil, Jaekeun; Lee, Nayoung; Ra, Sekin; Lee, Miejeen; Kim, Sora

    2013-02-01

    The Final goals are to achieve the 2nd goals of the Proton Engineering Frontier Project, development of proton beam utilization technologies, to incubate the potential users, and to develop fundamental technologies. Based on these achievements, we are going to enhance the accelerator utilization and maximize contribution to the local society after accelerator construction completion. For the these goals, we were operating user program reflecting the results of 3rd step planning. We support 38 small projects during 2 years. As results of activation of beam utilization, we acquired 768 users at the end of 2012. We survey proton beam technology proposals, individuals and institutions participation letter of intent through the research of 'Planning of a support program for both basic research by using accelerator and manpower cultivation'. And inaugurated KOPUA (Korea Proton Accelerator User Association) on March 28, 2012 with 152 members. We secured experimental conditions at TR23 and TR103 and reflected in the target room design and operation scenarios via investigate the requirements. Through these requirements, we make a remote sample transfer system, beam regulating system, hot cell and sample transport container. Moreover, we develop proton beam technologies such as in-vivo proton beam irradiation system, comparison of the biological effects for pulse beam and continuous beam, basic experiments for the metal nanopaticle synthesis, research for radioactivatied samples and devices, conceptual design and calculation for neutron source target and calculation of the isotope production yield. Proton accelerator can be utilized in a variety of field, including NT, BT, IT, ST, ET, Nuclear, medical, and some of the user facilities required were constructed through this project, Experience for the construction and operation of these facilities can be reflected to the construction of the rest 8 target room of proton accelerator center

  15. Handbook of social network technologies and applications

    CERN Document Server

    Furht, Borko

    2010-01-01

    Social networking is a concept that has existed for a long time; however, with the explosion of the Internet, social networking has become a tool for people to connect and communicate in ways that were impossible in the past. The recent development of Web 2.0 has provided many new applications, such as Myspace, Facebook, and LinkedIn. The purpose of ""Handbook of Social Networks: Technologies and Applications"" is to provide comprehensive guidelines on the current and future trends in social network technologies and applications in the field of Web-based Social Networks. This handbook includes

  16. User Multiplexing in Relay Enhanced LTE-Advanced Networks

    DEFF Research Database (Denmark)

    Teyeb, Oumer Mohammed; Frederiksen, Frank; Redana, Simone

    2010-01-01

    The 3rd Generation Partnership Project has recently started the standardization process for LTE-Advanced, as a major evolution step of UTRAN LTE Release 8. One of the key enhancing technologies being studied that may help to fulfill the challenging performance targets of LTE-Advanced networks is ...

  17. Users' attitude towards science and technology database system : INIS user needs survey

    International Nuclear Information System (INIS)

    Fukazawa, Takeyasu; Takahashi, Satoko; Yonezawa, Minoru; Kajiro, Tadashi; Mineo, Yukinobu; Habara, Takako; Komatsubara, Yasutoshi; Hiramatsu, Nobuaki; Habara, Tadashi.

    1995-01-01

    The International Nuclear Information System (INIS) is the world's leading information system on the peaceful use of nuclear energy which is being operated by the International Atomic Energy Agency (IAEA) in collaboration with its member-states and other international organizations. After more than 20 years of the operation of INIS, a user needs survey was conducted with the aim of assisting the INIS Secretariat to decide which way INIS should go. This report describes users' attitude towards that system on the basis of the conclusions drawn from the questionnaires sent out to the users by the Japan Atomic Energy Research Institute, the INIS national center in Japan, in close collaboration with the Japan Information Center of Science and Technology. (author)

  18. Networked Intimacy. Intimacy and Friendship among Italian Facebook users

    DEFF Research Database (Denmark)

    Farci, Manolo; Rossi, Luca; Boccia Artieri, Giovanni

    2016-01-01

    In this paper, we describe the results of a qualitative study conducted with 120 Italian Facebook users to investigate how Facebook enables people to achieve a mutually constitutive intimacy with their own friendship network: a negotiation of intimacy in public through self-disclosure, where the ...... that both systematizes and extends the findings identified in previous studies of intimacy on Facebook. We describe this framework as networked intimacy and we discuss the consequences of it in the light of already existing research on online self-disclosure.......In this paper, we describe the results of a qualitative study conducted with 120 Italian Facebook users to investigate how Facebook enables people to achieve a mutually constitutive intimacy with their own friendship network: a negotiation of intimacy in public through self-disclosure, where...... the affordances of the platform are useful to elicit significant reactions, validations and demonstrations of affection from others. We observed that, in order to achieve various levels of intimacy on Facebook, people engage in various strategies: Showing rather than telling, Sharing implicit content, Tagging...

  19. Users structure and behavior on an online social network during a political protest

    Science.gov (United States)

    Morales, A. J.; Losada, J. C.; Benito, R. M.

    2012-11-01

    Over the past years, new technologies and specially online social networks have penetrated into the world’s population at an accelerated pace. In this paper we analyze collected data from the web application Twitter, in order to describe the structure and dynamics of the emergent social networks, based on complexity science. We focused on a Venezuelan protest that took place exclusively by Twitter during December, 2010. We found a community structure with highly connected hubs and three different kinds of user behavior that determine the information flow dynamics. We noticed that even though online social networks appear to be a pure social environment, traditional media still holds loads of influence inside the network.

  20. Multipath TCP for user cooperation in wireless networks

    CERN Document Server

    Zhou, Dizhi

    2014-01-01

    This brief presents several enhancement modules to Multipath Transmission Control Protocol (MPTCP) in order to support stable and efficient multipath transmission with user cooperation in the Long Term Evolution (LTE) network. The text explains how these enhancements provide a stable aggregate throughput to the upper-layer applications; guarantee a steady goodput, which is the real application-layer perceived throughput; and ensure that the local traffic of the relays is not adversely affected when the relays are forwarding data for the destination. The performance of the proposed solutions is extensively evaluated using various scenarios. The simulation results demonstrate that the proposed modules can achieve a stable aggregate throughput and significantly improve the goodput by 1.5 times on average. The brief also shows that these extensions can well respect the local traffic of the relays and motivate the relay users to provide the relaying service.

  1. Latest Trends in Home Networking Technologies

    Science.gov (United States)

    Tsutsui, Akihiro

    Broadband access service, including FTTH, is now in widespread use in Japan. More than half of the households that have broadband Internet access construct local area networks (home networks) in their homes. In addition, information appliances such as personal computers, networked audio, and visual devices and game machines are connected to home networks, and many novel service applications are provided via the Internet. However, it is still difficult to install and incorporate these devices and services because networked devices have been developed in different communities. I briefly explain the current status of information appliances and home networking technologies and services and discuss some of the problems in this and their solutions.

  2. User-driven Innovation in a Supply and Value Network

    DEFF Research Database (Denmark)

    Cankaya, Alev; Lassen, Astrid Heidemann; Wandahl, Søren

    This article serves to conduct a systematic literary review upon the subject of user driven innovation in a supply and value network. The methodology behind the review is strict, organised, and controlled by peers in order to ensure that most of the relevant theory behind the subject is covered....... Seven categories of relevant literature were defined, analysed, and discussed, which resulted in a number of subjects for improvement in the current literature as well as a number of subjects that seem to be uncovered in theory today....

  3. User-friendly establishment of trust in distributed home automation networks

    DEFF Research Database (Denmark)

    Hjorth, Theis Solberg; Madsen, Per Printz; Torbensen, Rune

    2012-01-01

    these relationships can lead to misconfiguration or breaches of security. We outline a security system for Home Automation called Trusted Domain that can establish and maintain cryptographically secure relationships between devices connected via IP-based networks and the Internet. Trust establishment is presented...... in a simple and meaningful way that allows non-expert users to make the correct security decisions when enrolling new devices. We propose a social remote mutual authentication method called the PictogramDB Hash designed to easily and accurately verify certificate hash values by visualizing them with sequences......Current wireless technologies use a variety of methods to locally exchange and verify credentials between devices to establish trusted relationships. Scenarios in home automation networks also require this capability over the Internet, but the necessary involvement of non-expert users to setup...

  4. Security Technologies for Open Networking Environments (STONE)

    Energy Technology Data Exchange (ETDEWEB)

    Muftic, Sead

    2005-03-31

    -domain scenarios is supported by a set of security engines that represent the core of the Federated Identities Management Server, which is also an extension of the Domain Security Server. The Federated Identity Management server allows users to federate their identities or terminate the federation between the service provider and the identity provider. At the service provider web site, the users are offered a list of identity providers to which they can choose to federate their identities. After users federate their identity, they can perform Single Sign-On protocol in an environment of federated domains. The group security system consists of a number of security technologies under a unified architecture, which supports creation of secure groups and execution of secure group transactions and applications in an open networking environment. The system is based on extensions of the GSAKMP standard for group key distribution and management. The Top layer is the Security Infrastructure with the Security Management and Administration System components and protocols that provide security functions common to all secure network applications The Middle layer is the Secure Group Protocols and Applications layer, consisting of the Policy and Group Key Distribution Server and Web-based (thin) Client. The Bottom layer is the supporting Middleware Security Platform, the cryptographic platform already described above. The group security system is designed to perform the functions necessary to create secure groups and enable secure group applications. Specifically, the system can manage group roles, create and disseminate a group security policy, perform authentication and authorization of users using PKI certificates and Web services security, generate group keys, and recover from compromises. In accordance with the GSAKMP standard, the group security system must perform all the required group life-cycle functions: group definition, group establishment, group maintenance, and group removal. The

  5. The experience of living with stroke and using technology: opportunities to engage and co-design with end users.

    Science.gov (United States)

    Nasr, Nasrin; Leon, Beatriz; Mountain, Gail; Nijenhuis, Sharon M; Prange, Gerdienke; Sale, Patrizio; Amirabdollahian, Farshid

    2016-11-01

    We drew on an interdisciplinary research design to examine stroke survivors' experiences of living with stroke and with technology in order to provide technology developers with insight into values, thoughts and feelings of the potential users of a to-be-designed robotic technology for home-based rehabilitation of the hand and wrist. Ten stroke survivors and their family carers were purposefully selected. On the first home visit, they were introduced to cultural probe. On the second visit, the content of the probe packs were used as prompt to conduct one-to-one interviews with them. The data generated was analysed using thematic analysis. A third home visit was conducted to evaluate the early prototype. User requirements were categorised into their network of relationships, their attitude towards technology, their skills, their goals and motivations. The user requirements were used to envision the requirements of the system including providing feedback on performance, motivational aspects and usability of the system. Participants' views on the system requirements were obtained during a participatory evaluation. This study showed that prior to the development of technology, it is important to engage with potential users to identify user requirements and subsequently envision system requirements based on users' views. Implications for Rehabilitation An understanding of how stroke survivors make sense of their experiences of living with stroke is needed to design home-based rehabilitation technologies. Linking stroke survivors' goals, motivations, behaviour, feelings and attitude to user requirements prior to technology development has a significant impact on improving the design.

  6. An Optimal Joint User Association and Power Allocation Algorithm for Secrecy Information Transmission in Heterogeneous Networks

    Directory of Open Access Journals (Sweden)

    Rong Chai

    2017-01-01

    Full Text Available In recent years, heterogeneous radio access technologies have experienced rapid development and gradually achieved effective coordination and integration, resulting in heterogeneous networks (HetNets. In this paper, we consider the downlink secure transmission of HetNets where the information transmission from base stations (BSs to legitimate users is subject to the interception of eavesdroppers. In particular, we stress the problem of joint user association and power allocation of the BSs. To achieve data transmission in a secure and energy efficient manner, we introduce the concept of secrecy energy efficiency which is defined as the ratio of the secrecy transmission rate and power consumption of the BSs and formulate the problem of joint user association and power allocation as an optimization problem which maximizes the joint secrecy energy efficiency of all the BSs under the power constraint of the BSs and the minimum data rate constraint of user equipment (UE. By equivalently transforming the optimization problem into two subproblems, that is, power allocation subproblem and user association subproblem of the BSs, and applying iterative method and Kuhn-Munkres (K-M algorithm to solve the two subproblems, respectively, the optimal user association and power allocation strategies can be obtained. Numerical results demonstrate that the proposed algorithm outperforms previously proposed algorithms.

  7. 78 FR 17418 - Rural Health Information Technology Network Development Grant

    Science.gov (United States)

    2013-03-21

    ... Information Technology Network Development Grant AGENCY: Health Resources and Services Administration (HRSA...-competitive replacement award under the Rural Health Information Technology Network Development Grant (RHITND... relinquishing its fiduciary responsibilities for the Rural Health Information Technology Network Development...

  8. Networking Technologies for Future Home Networks Using 60 GHz Radio

    NARCIS (Netherlands)

    Wang, J.

    2010-01-01

    Networking technologies have been changing the life of people in their private residential space. With the arrival of high definition (HD) multimedia services and broadband communications into the living space, future home networks are expected to support high speed device-to-device connectivity

  9. Outage and ser performance of an opportunistic multi-user underlay cognitive network

    KAUST Repository

    Khan, Fahd Ahmed

    2012-10-01

    Consider a multi-user underlay cognitive network where multiple cognitive users concurrently share the spectrum with a primary network and a single secondary user is selected for transmission. The channel is assumed to have independent but not identical Nakagami-m fading. Closed form expressions for the outage performance and the symbol-error-rate performance of the opportunistic multi-user secondary network are derived when a peak interference power constraint is imposed on the secondary network in addition to the limited peak transmit power of each secondary user. © 2012 IEEE.

  10. Online social networks that connect users to physical activity partners: a review and descriptive analysis.

    Science.gov (United States)

    Nakhasi, Atul; Shen, Album Xiaotian; Passarella, Ralph Joseph; Appel, Lawrence J; Anderson, Cheryl Am

    2014-06-16

    The US Centers for Disease Control and Prevention have identified a lack of encouragement, support, or companionship from family and friends as a major barrier to physical activity. To overcome this barrier, online social networks are now actively leveraging principles of companion social support in novel ways. The aim was to evaluate the functionality, features, and usability of existing online social networks which seek to increase physical activity and fitness among users by connecting them to physical activity partners, not just online, but also face-to-face. In September 2012, we used 3 major databases to identify the website addresses for relevant online social networks. We conducted a Google search using 8 unique keyword combinations: the common keyword "find" coupled with 1 of 4 prefix terms "health," "fitness," "workout," or "physical" coupled with 1 of 2 stem terms "activity partners" or "activity buddies." We also searched 2 prominent technology start-up news sites, TechCrunch and Y Combinator, using 2 unique keyword combinations: the common keyword "find" coupled with 1 of 2 stem terms "activity partners" and "activity buddies." Sites were defined as online social health activity networks if they had the ability to (1) actively find physical activity partners or activities for the user, (2) offer dynamic, real-time tracking or sharing of social activities, and (3) provide virtual profiles to users. We excluded from our analysis sites that were not Web-based, publicly available, in English, or free. Of the 360 initial search results, we identified 13 websites that met our complete criteria of an online social health activity network. Features such as physical activity creation (13/13, 100%) and private messaging (12/13, 92%) appeared almost universally among these websites. However, integration with Web 2.0 technologies such as Facebook and Twitter (9/13, 69%) and the option of direct event joining (8/13, 62%) were not as universally present. Largely

  11. The dark side of technologies: technostress among users of information and communication technologies.

    Science.gov (United States)

    Salanova, Marisa; Llorens, Susana; Cifre, Eva

    2013-01-01

    This paper tests the structure and the predictors of two psychological experiences of technostress associated with the use of information and communication technologies (ICT), i.e., technostrain (users report feelings of anxiety, fatigue, scepticism and inefficacy beliefs related to the use of technologies) and technoaddiction (users feel bad due to an excessive and compulsive use of these technologies). The study included a sample of 1072 ICT users (N = 675 nonintensive ICT users and N = 397 intensive ICT users). Results from multigroup confirmatory factor analyses among non-intensive and intensive ICT users showed, as expected, the four-factor structure of technostrain in both samples. Secondly, and also as expected, confirmatory factorial analyses revealed that technostress experiences are characterized not only by technostrain but also by an excessive and compulsive use of ICT. Moreover, multiple analyses of variance showed significant differences between non-intensive and intensive ICT users (1) in the dimensions of technostress and (2) in specific job demands and job/personal resources. Finally, linear multiple regression analyses revealed that technostrain is positively predicted by work overload, role ambiguity, emotional overload, mobbing and obstacles hindering ICT use, as well as by lack of autonomy, transformational leadership, social support, ICT use facilitators and mental competences. Work overload, role ambiguity and mobbing, as well as the lack of emotional competences, positively predict technoaddiction. Theoretical and practical implications, in addition to future research, are discussed.

  12. EconBiz — Meeting User Needs with New Technology

    Directory of Open Access Journals (Sweden)

    Tamara Pianos

    2010-08-01

    Full Text Available Virtual libraries try to combine traditional library services with new document types and services. The first generation of virtual libraries mostly tried to offer services based on a library-centric view of information retrieval systems. New virtual libraries try to concentrate on user's needs, but this is often easier said than done. Restrictions like copyright laws, technical limitations and the like often make it difficult to meet user requirements. A number of studies documented these needs: easy-to-use, comprehensive yet focussed search, and easy access to print and online documents, subject specific, yet not too restricted to specific areas. The new EconBiz-portal, relaunched in August 2010, has a disciplinary focus on business and economics and related subjects. It includes about 6 million records from different databases. Based on search-engine technology Lucene/Solr, combined with a metadata framework developed by the ZBW, it allows fast, convenient and complex searches. The integration of the Standard-Thesaurus-for Economics supports researchers by suggesting key words and related terms. Information on the availability of the documents is also included. Documents can either be accessed online or ways are shown to material that is available in print only. Journals Online & Print, a service developed by the German Electronic Journals Library (EZB and the German Union Catalogue of Serials (ZDB is included to provide easy access to all forms of journals. In addition, services like an event calendar, a tutorial on how to find information and an online-reference desk help to cater to the user's complex needs. The new EconBiz-portal was developed by the ZBW in close cooperation with the USB Cologne. Major parts of the search engine framework were developed by a company specialized in information technology. This paper elaborates on the extraction of users' requirements from different studies, the deduction of functional requirements, and

  13. Green Mobile Clouds: Network Coding and User Cooperation for Improved Energy Efficiency

    DEFF Research Database (Denmark)

    Heide, Janus; Fitzek, Frank; Pedersen, Morten Videbæk

    2012-01-01

    This paper highlights the benefits of user cooperation and network coding for energy saving in cellular networks. It is shown that these techniques allow for reliable and efficient multicast services from both a user and network perspective. The working principles and advantages in terms of energy...... and spectrum usage is explained for user cooperation, network coding and a combination of both. For multicast services it is shown that the proposed approaches can save as much as 90% of the energy on the user side and 66% on network provider side for the topologies under investigation. One interesting finding...... is that user cooperation can be beneficial for the network operator even if some users refuse to cooperate....

  14. Future networks and technologies supporting innovative communications

    DEFF Research Database (Denmark)

    Prasad, Ramjee

    2012-01-01

    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...

  15. Solar sorptive cooling. Technologies, user requirements, practical experience, future prospects

    Energy Technology Data Exchange (ETDEWEB)

    Treffinger, P. [DLR Deutsches Zentrum fuer Luft- und Raumfahrt e.V., Hardthausen (Germany); Hertlein, H.P. [eds.] [Forschungsverbund Sonnenenergie, Koeln (Germany)

    1998-09-01

    Sorptive cooling techniques permit the use of low-temperature solar heat, i.e. a renewable energy of low cost and world-wide availability. The Forschungsverbund Sonnenenergie intends to develop solar sorptive cooling technologies to the prototype stage and, in cooperation with the solar industry and its end users, to promote practical application in air conditioning of buildings and cold storage of food. The workshop presents an outline of the state of development of solar sorptive cooling from the view of users and developers. Exemplary solar cooling systems are described, and the potential of open and closed sorptive processes is assessed. Future central activities will be defined in an intensive discussion between planners, producers, users and developers. [German] Der Einsatz von Sorptionstechniken zur Kaelteerzeugung erlaubt es, als treibende Solarenergie Niedertemperatur-Solarwaerme einzusetzen, also eine regenerative Energie mit sehr geringen Kosten und weltweiter Verfuegbarkeit. Der Forschungsverbund Sonnenenergie hat sich als Aufgabe gestellt, die Techniken der solaren Sorptionskuehlung bis zum Prototyp zu entwickeln und mit Industrie und Nutzern die praktische Anwendung voranzubringen. Die Anwendungsfelder sind die Klimatisierung von Gebaeuden und die Kaltlagerung von Lebensmitteln. Der Workshop gibt einen Ueberblick zum Entwicklungsstand der solaren Sorptionskuehlung aus der Sicht der Anwender und Entwickler. Bereits ausgefuehrte Beispiele zur solaren Kuehlung werden vorgestellt und das Potential geschlossener und offener Sorptionsverfahren angegeben. In intensiver Diskussion zwischen Planern, Herstellern, Nutzern und Entwicklern sollen kuenftige Arbeitsschwerpunkte herausgearbeitet werden. (orig.)

  16. Progress of the European Assistive Technology Information Network.

    Science.gov (United States)

    Gower, Valerio; Andrich, Renzo

    2015-01-01

    The European Assistive Technology Information Network (EASTIN), launched in 2005 as the result of a collaborative EU project, provides information on Assistive Technology products and related material through the website www.eastin.eu. In the past few years several advancements have been implemented on the EASTIN website thanks to the contribution of EU funded projects, including a multilingual query processing component for supporting non expert users, a user rating and comment facility, and a detailed taxonomy for the description of ICT based assistive products. Recently, within the framework of the EU funded project Cloud4All, the EASTIN information system has also been federated with the Unified Listing of assistive products, one of the building blocks of the Global Public Inclusive Infrastructure initiative.

  17. Network and User-Perceived Performance of Web Page Retrievals

    Science.gov (United States)

    Kruse, Hans; Allman, Mark; Mallasch, Paul

    1998-01-01

    The development of the HTTP protocol has been driven by the need to improve the network performance of the protocol by allowing the efficient retrieval of multiple parts of a web page without the need for multiple simultaneous TCP connections between a client and a server. We suggest that the retrieval of multiple page elements sequentially over a single TCP connection may result in a degradation of the perceived performance experienced by the user. We attempt to quantify this perceived degradation through the use of a model which combines a web retrieval simulation and an analytical model of TCP operation. Starting with the current HTTP/l.1 specification, we first suggest a client@side heuristic to improve the perceived transfer performance. We show that the perceived speed of the page retrieval can be increased without sacrificing data transfer efficiency. We then propose a new client/server extension to the HTTP/l.1 protocol to allow for the interleaving of page element retrievals. We finally address the issue of the display of advertisements on web pages, and in particular suggest a number of mechanisms which can make efficient use of IP multicast to send advertisements to a number of clients within the same network.

  18. Report of the advisory group meeting on the establishment of regional ion accelerator centers and user networks

    International Nuclear Information System (INIS)

    1997-11-01

    In this report it is shown that ion accelerators have had a tremendous economic and technological impact on most developed countries, and are beginning to have a significant impact on developing countries. Through the formation of Accelerator Centers and User Networks (which may be national, regional or inter-regional) a mechanism will be outlined by which scientists and other users from developing countries can receive the necessary training and have available the necessary accelerator facilities to use these machines for economic improvement and technological development in their countries

  19. Network operating system focus technology

    Science.gov (United States)

    1985-01-01

    An activity structured to provide specific design requirements and specifications for the Space Station Data Management System (DMS) Network Operating System (NOS) is outlined. Examples are given of the types of supporting studies and implementation tasks presently underway to realize a DMS test bed capability to develop hands-on understanding of NOS requirements as driven by actual subsystem test beds participating in the overall Johnson Space Center test bed program. Classical operating system elements and principal NOS functions are listed.

  20. Managing a User’s Vulnerability on a Social Networking Site

    Science.gov (United States)

    2015-05-01

    Attributes. Social Media Related Work is Highlighted in Bold . . . . . . . . . . . . . . . . . . . . 70 viii LIST OF FIGURES Figure Page 1.1 User Types...aid not only the cyberbullying of teenagers but also the cyberstalking and cyberharassment of adults3. On a social networking site, an individual user...i.e., Q2 users). For the rest of this chapter, they are simply referred as users, unless otherwise stated. Social media wants their users to be more

  1. Efficiency Loss of Mixed Equilibrium Associated with Altruistic Users and Logit-based Stochastic Users in Transportation Network

    Directory of Open Access Journals (Sweden)

    Xiao-Jun Yu

    2014-02-01

    Full Text Available The efficiency loss of mixed equilibrium associated with two categories of users is investigated in this paper. The first category of users are altruistic users (AU who have the same altruism coefficient and try to minimize their own perceived cost that assumed to be a linear combination of selfish com­ponent and altruistic component. The second category of us­ers are Logit-based stochastic users (LSU who choose the route according to the Logit-based stochastic user equilib­rium (SUE principle. The variational inequality (VI model is used to formulate the mixed route choice behaviours associ­ated with AU and LSU. The efficiency loss caused by the two categories of users is analytically derived and the relations to some network parameters are discussed. The numerical tests validate our analytical results. Our result takes the re­sults in the existing literature as its special cases.

  2. Solar Cooking Technology - How Far are Technology Promoters and Users from Each Other?

    DEFF Research Database (Denmark)

    Ahmad, Bashir

    1999-01-01

    In this article we take up the issue of use and disuse of box solar cookers by discussing some basic underlying assumptions of the technology as put forward (directly or indirectly) by technology promoter actors. We confront the assumptions with some practical realities that the users and disusers...... encounter when they practice solar cooking. In this way on the one hand some facts which have been instrumental for developing of technology on the side of technology developers are opened up. And on the other hand related practical aspects of use and disuse such as place and time for solar cooking...

  3. Organizing for Networked Information Technologies

    DEFF Research Database (Denmark)

    The book provides seven practical examples of how Danish companies implemented new information technology in order to transform their internal and external business processes. The purpose is to share some of the companies' concerns and hopes during this implementation process, with each case...

  4. Networking and Information Technology Workforce Study: Final Report

    Data.gov (United States)

    Networking and Information Technology Research and Development, Executive Office of the President — This report presents the results of a study of the global Networking and Information Technology NIT workforce undertaken for the Networking and Information...

  5. Making Wireless Networks Secure for NASA Mission Critical Applications Using Virtual Private Network (VPN) Technology

    Science.gov (United States)

    Nichols, Kelvin F.; Best, Susan; Schneider, Larry

    2004-01-01

    With so many security issues involved with wireless networks, the technology has not been fully utilized in the area of mission critical applications. These applications would include the areas of telemetry, commanding, voice and video. Wireless networking would allow payload operators the mobility to take computers outside of the control room to their off ices and anywhere else in the facility that the wireless network was extended. But the risk is too great of having someone sit just inside of your wireless network coverage and intercept enough of your network traffic to steal proprietary data from a payload experiment or worse yet hack back into your system and do even greater harm by issuing harmful commands. Wired Equivalent Privacy (WEP) is improving but has a ways to go before it can be trusted to protect mission critical data. Today s hackers are becoming more aggressive and innovative, and in order to take advantage of the benefits that wireless networking offer, appropriate security measures need to be in place that will thwart hackers. The Virtual Private Network (VPN) offers a solution to the security problems that have kept wireless networks from being used for mission critical applications. VPN provides a level of encryption that will ensure that data is protected while it is being transmitted over a wireless local area network (LAN). The VPN allows a user to authenticate to the site that the user needs to access. Once this authentication has taken place the network traffic between that site and the user is encapsulated in VPN packets with the Triple Data Encryption Standard (3DES). 3DES is an encryption standard that uses a single secret key to encrypt and decrypt data. The length of the encryption key is 168 bits as opposed to its predecessor DES that has a 56-bit encryption key. Even though 3DES is the common encryption standard for today, the Advance Encryption Standard (AES), which provides even better encryption at a lower cycle cost is growing

  6. Tracking mobile users in wireless networks via semi-supervised colocalization.

    Science.gov (United States)

    Pan, Jeffrey Junfeng; Pan, Sinno Jialin; Yin, Jie; Ni, Lionel M; Yang, Qiang

    2012-03-01

    Recent years have witnessed the growing popularity of sensor and sensor-network technologies, supporting important practical applications. One of the fundamental issues is how to accurately locate a user with few labeled data in a wireless sensor network, where a major difficulty arises from the need to label large quantities of user location data, which in turn requires knowledge about the locations of signal transmitters or access points. To solve this problem, we have developed a novel machine learning-based approach that combines collaborative filtering with graph-based semi-supervised learning to learn both mobile users' locations and the locations of access points. Our framework exploits both labeled and unlabeled data from mobile devices and access points. In our two-phase solution, we first build a manifold-based model from a batch of labeled and unlabeled data in an offline training phase and then use a weighted k-nearest-neighbor method to localize a mobile client in an online localization phase. We extend the two-phase colocalization to an online and incremental model that can deal with labeled and unlabeled data that come sequentially and adapt to environmental changes. Finally, we embed an action model to the framework such that additional kinds of sensor signals can be utilized to further boost the performance of mobile tracking. Compared to other state-of-the-art systems, our framework has been shown to be more accurate while requiring less calibration effort in our experiments performed on three different testbeds.

  7. Privacy and technology challenges for ubiquitous social networking

    DEFF Research Database (Denmark)

    Sapuppo, Antonio; Seet, Boon-Chong

    2015-01-01

    towards important challenges such as social sensing, enabling social networking and privacy protection. In this paper we firstly investigate the methods and technologies for acquisition of the relevant context for promotion of sociability among inhabitants of USN environments. Afterwards, we review...... architectures and techniques for enabling social interactions between participants. Finally, we identify privacy as the major challenge for networking in USN environments. Consequently, we depict design guidelines and review privacy protection models for facilitating personal information disclosure.......Ubiquitous social networking (USN) can be seen as an evolution of ubiquitous computing supporting the social well–being of people in their everyday lives. The vision of USN focuses on enhancing social interactions among its participants during users' physical meetings. This target is leading...

  8. Gigabit Satellite Network for NASA's Advanced Communication Technology Satellite (ACTS)

    Science.gov (United States)

    Hoder, Douglas; Bergamo, Marcos

    1996-01-01

    The advanced communication technology satellite (ACTS) gigabit satellite network provides long-haul point-to-point and point-to-multipoint full-duplex SONET services over NASA's ACTS. at rates up to 622 Mbit/s (SONET OC-12), with signal quality comparable to that obtained with terrestrial fiber networks. Data multiplexing over the satellite is accomplished using time-division multiple access (TDMA) techniques coordinated with the switching and beam hopping facilities provided by ACTS. Transmissions through the satellite are protected with Reed-Solomon encoding. providing virtually error-free transmission under most weather conditions. Unique to the system are a TDMA frame structure and satellite synchronization mechanism that allow: (a) very efficient utilization of the satellite capacity: (b) over-the-satellite dosed-loop synchronization of the network in configurations with up to 64 ground stations: and (c) ground station initial acquisition without collisions with existing signalling or data traffic. The user interfaces are compatible with SONET standards, performing the function of conventional SONET multiplexers and. as such. can be: readily integrated with standard SONET fiber-based terrestrial networks. Management of the network is based upon the simple network management protocol (SNMP). and includes an over-the-satellite signalling network and backup terrestrial internet (IP-based) connectivity. A description of the ground stations is also included.

  9. Optical Network Technologies for Future Digital Cinema

    Directory of Open Access Journals (Sweden)

    Sajid Nazir

    2016-01-01

    Full Text Available Digital technology has transformed the information flow and support infrastructure for numerous application domains, such as cellular communications. Cinematography, traditionally, a film based medium, has embraced digital technology leading to innovative transformations in its work flow. Digital cinema supports transmission of high resolution content enabled by the latest advancements in optical communications and video compression. In this paper we provide a survey of the optical network technologies for supporting this bandwidth intensive traffic class. We also highlight the significance and benefits of the state of the art in optical technologies that support the digital cinema work flow.

  10. Technologies for physical activity self-monitoring: a study of differences between users and non-users

    Directory of Open Access Journals (Sweden)

    Åkerberg A

    2017-02-01

    Full Text Available Anna Åkerberg,1,2 Anne Söderlund,2 Maria Lindén1 1School of Innovation, Design and Engineering, 2School of Health, Care and Social Welfare, Mälardalen University, Västerås, Sweden Background: Different kinds of physical activity (PA self-monitoring technologies are used today to monitor and motivate PA behavior change. The user focus is essential in the development process of this technology, including potential future users such as representatives from the group of non-users. There is also a need to study whether there are differences between the groups of users and non-users. The aims of this study were to investigate possible differences between users and non-users regarding their opinions about PA self-monitoring technologies and to investigate differences in demographic variables between the groups. Materials and methods: Participants were randomly selected from seven municipalities in central Sweden. In total, 107 adults responded to the Physical Activity Products Questionnaire, which consisted of 22 questions. Results: Significant differences between the users and non-users were shown for six of the 20 measurement-related items: measures accurately (p=0.007, measures with high precision (p=0.024, measures distance (p=0.020, measures speed (p=0.003, shows minutes of activity (p=0.004, and shows geographical position (p=0.000. Significant differences between the users and non-users were also found for two of the 29 encouragement items: measures accurately (p=0.001 and has long-term memory (p=0.019. Significant differences between the groups were also shown for level of education (p=0.030 and level of physical exercise (p=0.037. Conclusion: With a few exceptions, the users and the non-users in this study had similar opinions about PA self-monitoring technologies. Because this study showed significant differences regarding level of education and level of physical exercise, these demographic variables seemed more relevant to investigate

  11. Transport Network Technologies – Study and Testing

    DEFF Research Database (Denmark)

    Bozorgebrahimi, K.; Channegowda, M.; Colmenero, A.

    Following on from the theoretical research into Carrier Class Transport Network Technologies (CCTNTs) documented in DJ1.1.1, this report describes the extensive testing performed by JRA1 Task 1. The tests covered EoMPLS, Ethernet OAM, Synchronous Ethernet, PBB-TE, MPLS-TP, OTN and GMPLS, and the ......Following on from the theoretical research into Carrier Class Transport Network Technologies (CCTNTs) documented in DJ1.1.1, this report describes the extensive testing performed by JRA1 Task 1. The tests covered EoMPLS, Ethernet OAM, Synchronous Ethernet, PBB-TE, MPLS-TP, OTN and GMPLS...

  12. Online Actions with Offline Impact: How Online Social Networks Influence Online and Offline User Behavior.

    Science.gov (United States)

    Althoff, Tim; Jindal, Pranav; Leskovec, Jure

    2017-02-01

    Many of today's most widely used computing applications utilize social networking features and allow users to connect, follow each other, share content, and comment on others' posts. However, despite the widespread adoption of these features, there is little understanding of the consequences that social networking has on user retention, engagement, and online as well as offline behavior. Here, we study how social networks influence user behavior in a physical activity tracking application. We analyze 791 million online and offline actions of 6 million users over the course of 5 years, and show that social networking leads to a significant increase in users' online as well as offline activities. Specifically, we establish a causal effect of how social networks influence user behavior. We show that the creation of new social connections increases user online in-application activity by 30%, user retention by 17%, and user offline real-world physical activity by 7% (about 400 steps per day). By exploiting a natural experiment we distinguish the effect of social influence of new social connections from the simultaneous increase in user's motivation to use the app and take more steps. We show that social influence accounts for 55% of the observed changes in user behavior, while the remaining 45% can be explained by the user's increased motivation to use the app. Further, we show that subsequent, individual edge formations in the social network lead to significant increases in daily steps. These effects diminish with each additional edge and vary based on edge attributes and user demographics. Finally, we utilize these insights to develop a model that accurately predicts which users will be most influenced by the creation of new social network connections.

  13. Applicability of new radio technologies for advanced UMTS networks

    Directory of Open Access Journals (Sweden)

    A. Dekorsy

    2004-01-01

    Full Text Available An expanded effort is under the way to support the evolution of UMTS (Universal Mobile Telecommunication System. Apart from delivering high data rates, future UMTS releases will also require to provide high network performance in terms of system capacity, low radiated power, and high coverage. Well promising performance-enhancing technologies are smart antennas as well as multiuser detection. Although these new radio technologies have recently been subject to intense research, main UMTS network integration aspects with their specific constraints have been neglected in many cases. Especially the interaction with UMTS radio resource control being required to meet Quality of Service (QoS constraints has to be included to assess the applicability of these technologies for UMTS. In this paper, we study the interaction of beamforming concepts as well as multiuser detection with load and power control. We also work out UMTS specific constraints like signal-to-interference-plus-noise ratio (SINR operating points, pilot power pollution or channel estimation, all strongly limiting network performance. Results are shown for capacity gains and power reduction for all beamforming concepts of interest as well as linear multiuser detection schemes. The results show that fix as well as user-specific beamforming significantly improves network performance gains in downlink. In uplink multiuser detection indicates fairly modest system capacity gains, while it reduces tremendously mobile station power.

  14. Wireless local area network. A new technology of network

    International Nuclear Information System (INIS)

    Wu Yunjun; Zhao Zongtao

    2003-01-01

    This paper introduces Wireless Local Area Network (WLAN), including the concept, history, characters and the foreground of its development, it also narrates in detail the several key techniques used to implement IEEE802.11 WLAN, and ideas on key technology of future progress in wireless LAN field have also been presented. (authors)

  15. Does Sentiment Among Users in Online Social Networks Polarize or Balance Out?

    DEFF Research Database (Denmark)

    Trier, Matthias; Hillmann, Robert

    2017-01-01

    Users express and share sentiments electronically when they communicate within online social network applications. One way to analyze such interdependent data is focusing on the inter-user relationships by applying a sociological perspective based on social network analysis. Existing studies...... examined the existence or distribution of sentiments in online communication at a general level or in small observed groups....

  16. Network Distributed Monitoring System Based on Robot Technology Middleware

    Directory of Open Access Journals (Sweden)

    Kunikatsu Takase

    2008-11-01

    Full Text Available In this paper, a network distributed monitoring system for human assistance robot system was developed to improve the interaction among the users and local service robotic system and enable a remote user to get a better understanding of what is going on in the local environment. Home integration robot system and network monitoring system using QuickCam Orbit cameras were developed and demonstrated from June 9 to June 19 at the 2005 World Exposition, Aichi, Japan. Improvements of network distributed monitoring system using IEEE1394 cameras with high performance and high resolution have been done in order to extend the application of system. Robot Technology Middleware (RTM was used in the developed system. By using RTM, we can develop cameras functional elements as RT software components that can be implemented by different programming languages, run in different operating system, or connected in different networks to interoperate.It is also easy to create comprehensive robot system application by reusing existing modules thus facilitating networkdistributed software sharing and improving the cost of writing and maintaining software.

  17. The Comparison of Attitudes Toward Infidelity and Religious Orientation in Facebook Social Network users and non-users

    Directory of Open Access Journals (Sweden)

    سیدهادی سیدعلی تبار

    2015-12-01

    Full Text Available This study aimed to compare attitudes towards infidelity and religious orientation in users and non-users of Facebook social network. This research was basic in terms of purpose and casual-comparative in terms of data collection. The study population included all married men and women referring to consulting centers of Tehran. A sample of 280 people (109 users an-d 171 non-users were selected through convenience sampling. Attitude toward Infidelity Scale and Religious Orientation Scale were used to collect the data and analyzed with Multivariate Analysis of Variance (MANOVA. Results showed that internal religious orientation (P0.05. This study suggests that using Facebook does not have any impact on attitude toward infidelity singly, but it can cause differences in internal and external religious orientation among Facebook users.

  18. Technology assessment of multileaf collimation: a North American users survey

    International Nuclear Information System (INIS)

    Klein, Eric E.; Tepper, Joel; Sontag, Mark; Franklin, Michael; Ling, Clifton; Kubo, Dale

    1999-01-01

    Purpose: The American Association of Physicists in Medicine (AAPM) initiated an Assessment of Technology Subcommittee (ATS) to help the radiotherapy community evaluate emerging technologies. The ATS decided to first address multileaf collimation (MLC) by means of a North American users survey. The survey attempted to address issues such as MLC utility, efficacy, cost-effectiveness, and customer satisfaction. Methods and Materials: The survey was designed with 38 questions, with cross-tabulation set up to decipher a particular clinic's perception of MLC. The surveys were coded according to MLC types, which were narrowed to four: Elekta, Siemens, Varian 52-leaf, and Varian 80-leaf. A 40% return rate was desired. Results: A 44% (108 of 250) return was achieved. On an MLC machine, 76.5% of photon patients are being treated with MLC. The main reasons for not using MLC were stair stepping, field size limitation, and physician objection. The most common sites in which MLC is being used are lung, pelvis, and prostate. The least used sites are head and neck and mantle fields. Of the facilities, 31% claimed an increase in number of patients being treated since MLC was installed, and 44% claimed an increase in the number of fields. Though the staffing for block cutting has decreased, therapist staffing has not. However, 91% of the facilities claimed a decreased workload for the therapists, despite the increase in daily treated patients and fields. Of the facilities that justified MLC purchase for more daily patients, 63% are actually treating more patients. Only 26% of the facilities that justified an MLC purchase for intensity-modulated radiotherapy (IMRT) are currently using it for that purpose. The satisfaction rating (1 = low to 5 = high) for department groups averaged 4.0. Therapists ranked MLC as 4.6. Conclusions: Our survey shows that most users have successfully introduced MLC into the clinic as a block replacement. Most have found MLC to be cost-effective and

  19. User profiling and classification for fraud detection in mobile communications networks

    OpenAIRE

    Hollmén, Jaakko

    2000-01-01

    The topic of this thesis is fraud detection in mobile communications networks by means of user profiling and classification techniques. The goal is to first identify relevant user groups based on call data and then to assign a user to a relevant group. Fraud may be defined as a dishonest or illegal use of services, with the intention to avoid service charges. Fraud detection is an important application, since network operators lose a relevant portion of their revenue to fraud. Whereas the int...

  20. Outdoor Lighting Networks: Market, Technologies and Standards

    NARCIS (Netherlands)

    Cavalcanti, D.; Wang, J.; Chen, R.; Jiang , D.; Yang, Y.

    2012-01-01

    Providing the right amount of light where and when it is needed is an opportunity to transform today’s cities into smart and livable urban spaces. New technologies are being introduced, such are adaptivecontrols and outdoor lighting networks, which can deliver energy andcost savings through adaptive

  1. Using Citation Network Analysis in Educational Technology

    Science.gov (United States)

    Cho, Yonjoo; Park, Sunyoung

    2012-01-01

    Previous reviews in the field of Educational Technology (ET) have revealed some publication patterns according to authors, institutions, and affiliations. However, those previous reviews focused only on the rankings of individual authors and institutions, and did not provide qualitative details on relations and networks of scholars and scholarly…

  2. Are the users of social networking sites homogeneous? A cross-cultural study.

    Science.gov (United States)

    Alarcón-Del-Amo, María-Del-Carmen; Gómez-Borja, Miguel-Ángel; Lorenzo-Romero, Carlota

    2015-01-01

    The growing use of Social Networking Sites (SNS) around the world has made it necessary to understand individuals' behaviors within these sites according to different cultures. Based on a comparative study between two different European countries (The Netherlands versus Spain), a comparison of typologies of networked Internet users has been obtained through a latent segmentation approach. These typologies are based on the frequency with which users perform different activities, their socio-demographic variables, and experience in social networking and interaction patterns. The findings show new insights regarding international segmentation in order to analyse SNS user behaviors in both countries. These results are relevant for marketing strategists eager to use the communication potential of networked individuals and for marketers willing to explore the potential of online networking as a low cost and a highly efficient alternative to traditional networking approaches. For most businesses, expert users could be valuable opinion leaders and potential brand influencers.

  3. Are the users of social networking sites homogeneous? A cross-cultural study

    Science.gov (United States)

    Alarcón-del-Amo, María-del-Carmen; Gómez-Borja, Miguel-Ángel; Lorenzo-Romero, Carlota

    2015-01-01

    The growing use of Social Networking Sites (SNS) around the world has made it necessary to understand individuals' behaviors within these sites according to different cultures. Based on a comparative study between two different European countries (The Netherlands versus Spain), a comparison of typologies of networked Internet users has been obtained through a latent segmentation approach. These typologies are based on the frequency with which users perform different activities, their socio-demographic variables, and experience in social networking and interaction patterns. The findings show new insights regarding international segmentation in order to analyse SNS user behaviors in both countries. These results are relevant for marketing strategists eager to use the communication potential of networked individuals and for marketers willing to explore the potential of online networking as a low cost and a highly efficient alternative to traditional networking approaches. For most businesses, expert users could be valuable opinion leaders and potential brand influencers. PMID:26321971

  4. Are the users of Social Networking Sites homogeneous? A cross-cultural study

    Directory of Open Access Journals (Sweden)

    MARÍA-DEL-CARMEN eALARCÓN-DEL-AMO

    2015-08-01

    Full Text Available The growing use of Social Networking Sites (SNS around the world has made it necessary to understand individuals’ behaviours within these sites according to different cultures. Based on a comparative study between two different European countries (The Netherlands versus Spain, a comparison of typologies of networked Internet users has been obtained through a latent segmentation approach. These typologies are based on the frequency with which users perform different activities, their socio-demographic variables, and experience in social networking and interaction patterns. The findings show new insights regarding international segmentation in order to analyse SNS user behaviours in both countries. These results are relevant for marketing strategists eager to use the communication potential of networked individuals and for marketers willing to explore the potential of online networking as a low cost and a highly efficient alternative to traditional networking approaches. For most businesses, expert users could be valuable opinion leaders and potential brand influencers.

  5. Delays and user performance in human-computer-network interaction tasks.

    Science.gov (United States)

    Caldwell, Barrett S; Wang, Enlie

    2009-12-01

    This article describes a series of studies conducted to examine factors affecting user perceptions, responses, and tolerance for network-based computer delays affecting distributed human-computer-network interaction (HCNI) tasks. HCNI tasks, even with increasing computing and network bandwidth capabilities, are still affected by human perceptions of delay and appropriate waiting times for information flow latencies. Conducted were 6 laboratory studies with university participants in China (Preliminary Experiments 1 through 3) and the United States (Experiments 4 through 6) to examine users' perceptions of elapsed time, effect of perceived network task performance partners on delay tolerance, and expectations of appropriate delays based on task, situation, and network conditions. Results across the six experiments indicate that users' delay tolerance and estimated delay were affected by multiple task and expectation factors, including task complexity and importance, situation urgency and time availability, file size, and network bandwidth capacity. Results also suggest a range of user strategies for incorporating delay tolerance in task planning and performance. HCNI user experience is influenced by combinations of task requirements, constraints, and understandings of system performance; tolerance is a nonlinear function of time constraint ratios or decay. Appropriate user interface tools providing delay feedback information can help modify user expectations and delay tolerance. These tools are especially valuable when delay conditions exceed a few seconds or when task constraints and system demands are high. Interface designs for HCNI tasks should consider assistant-style presentations of delay feedback, information freshness, and network characteristics. Assistants should also gather awareness of user time constraints.

  6. Assessing the user experience of older adults using a neural network trained to recognize emotions from brain signals.

    Science.gov (United States)

    Meza-Kubo, Victoria; Morán, Alberto L; Carrillo, Ivan; Galindo, Gilberto; García-Canseco, Eloisa

    2016-08-01

    The use of Ambient Assisted Living (AAL) technologies as a means to cope with problems that arise due to an increasing and aging population is becoming usual. AAL technologies are used to prevent, cure and improve the wellness and health conditions of the elderly. However, their adoption and use by older adults is still a major challenge. User Experience (UX) evaluations aim at aiding on this task, by identifying the experience that a user has while interacting with an AAL technology under particular conditions. This may help designing better products and improve user engagement and adoption of AAL solutions. However, evaluating the UX of AAL technologies is a difficult task, due to the inherent limitations of their subjects and of the evaluation methods. In this study, we validated the feasibility of assessing the UX of older adults while they use a cognitive stimulation application using a neural network trained to recognize pleasant and unpleasant emotions from electroencephalography (EEG) signals by contrasting our results with those of additional self-report and qualitative analysis UX evaluations. Our study results provide evidence about the feasibility of assessing the UX of older adults using a neural network that take as input the EEG signals; the classification accuracy of our neural network ranges from 60.87% to 82.61%. As future work we will conduct additional UX evaluation studies using the three different methods, in order to appropriately validate these results. Copyright © 2016 Elsevier Inc. All rights reserved.

  7. Insecure Network, Unknown Connection: Understanding Wi-Fi Privacy Assumptions of Mobile Device Users

    OpenAIRE

    Bonné, Bram; Rovelo Ruiz, Gustavo; Quax, Peter; Lamotte, Wim

    2017-01-01

    Smartphones and other mobile devices have proliferated in the past five years. The expectation of mobile device users to always be online has led to Wi-Fi networks being offered by a variety of providers. Using these networks introduces multiple security risks. In this work, we assess to what extent the privacy stance of mobile device users corresponds with their actual behavior by conducting a study with 108 participants. Our methodology consists of monitoring Wi-Fi networks that the partici...

  8. State criminal justice telecommunications (STACOM). Volume 4: Network design software user's guide

    Science.gov (United States)

    Lee, J. J.

    1977-01-01

    A user's guide to the network design program is presented. The program is written in FORTRAN V and implemented on a UNIVAC 1108 computer under the EXEC-8 operating system which enables the user to construct least-cost network topologies for criminal justice digital telecommunications networks. A complete description of program features, inputs, processing logic, and outputs is presented, and a sample run and a program listing are included.

  9. Examining Engineering & Technology Students' Acceptance of Network Virtualization Technology Using the Technology Acceptance Model

    Science.gov (United States)

    Yousif, Wael K.

    2010-01-01

    This causal and correlational study was designed to extend the Technology Acceptance Model (TAM) and to test its applicability to Valencia Community College (VCC) Engineering and Technology students as the target user group when investigating the factors influencing their decision to adopt and to utilize VMware as the target technology. In…

  10. Efficient and anonymous two-factor user authentication in wireless sensor networks: achieving user anonymity with lightweight sensor computation.

    Science.gov (United States)

    Nam, Junghyun; Choo, Kim-Kwang Raymond; Han, Sangchul; Kim, Moonseong; Paik, Juryon; Won, Dongho

    2015-01-01

    A smart-card-based user authentication scheme for wireless sensor networks (hereafter referred to as a SCA-WSN scheme) is designed to ensure that only users who possess both a smart card and the corresponding password are allowed to gain access to sensor data and their transmissions. Despite many research efforts in recent years, it remains a challenging task to design an efficient SCA-WSN scheme that achieves user anonymity. The majority of published SCA-WSN schemes use only lightweight cryptographic techniques (rather than public-key cryptographic techniques) for the sake of efficiency, and have been demonstrated to suffer from the inability to provide user anonymity. Some schemes employ elliptic curve cryptography for better security but require sensors with strict resource constraints to perform computationally expensive scalar-point multiplications; despite the increased computational requirements, these schemes do not provide user anonymity. In this paper, we present a new SCA-WSN scheme that not only achieves user anonymity but also is efficient in terms of the computation loads for sensors. Our scheme employs elliptic curve cryptography but restricts its use only to anonymous user-to-gateway authentication, thereby allowing sensors to perform only lightweight cryptographic operations. Our scheme also enjoys provable security in a formal model extended from the widely accepted Bellare-Pointcheval-Rogaway (2000) model to capture the user anonymity property and various SCA-WSN specific attacks (e.g., stolen smart card attacks, node capture attacks, privileged insider attacks, and stolen verifier attacks).

  11. Review of ride quality technology needs of industry and user groups

    Science.gov (United States)

    Mckenzie, J. R.; Brumaghim, S. H.

    1975-01-01

    A broad survey of ride quality technology state-of-the-art and a review of user evaluation of this technology were conducted. During the study 17 users of ride quality technology in 10 organizations representing land, marine and air passenger transportation modes were interviewed. Interim results and conclusions of this effort are reported.

  12. A User-Customized Virtual Network Platform for NaaS Cloud

    Directory of Open Access Journals (Sweden)

    Lei Xiao

    2016-01-01

    Full Text Available Now all kinds of public cloud providers take computing and storage resources as the user’s main demand, making it difficult for users to deploy complex network in the public cloud. This paper proposes a virtual cloud platform with network as the core demand of the user, which can provide the user with the capacity of free network architecture as well as all kinds of virtual resources. The network is isolated by port groups of the virtual distributed switch and the data forwarding and access control between different network segments are implemented by virtual machines loading a soft-routing system. This paper also studies the management interface of network architecture and the uniform way to connect the remote desktop of virtual resources on the web, hoping to provide some new ideas for the Network as a Service model.

  13. Effect of the social influence on topological properties of user-object bipartite networks

    Science.gov (United States)

    Liu, Jian-Guo; Hu, Zhaolong; Guo, Qiang

    2013-11-01

    Social influence plays an important role in analyzing online users' collective behaviors [Salganik et al., Science 311, 854 (2006)]. However, the effect of the social influence from the viewpoint of theoretical model is missing. In this paper, by taking into account the social influence and users' preferences, we develop a theoretical model to analyze the topological properties of user-object bipartite networks, including the degree distribution, average nearest neighbor degree and the bipartite clustering coefficient, as well as topological properties of the original user-object networks and their unipartite projections. According to the users' preferences and the global ranking effect, we analyze the theoretical results for two benchmark data sets, Amazon and Bookcrossing, which are approximately consistent with the empirical results. This work suggests that this model is feasible to analyze topological properties of bipartite networks in terms of the social influence and the users' preferences.

  14. Neural network technologies for image classification

    Science.gov (United States)

    Korikov, A. M.; Tungusova, A. V.

    2015-11-01

    We analyze the classes of problems with an objective necessity to use neural network technologies, i.e. representation and resolution problems in the neural network logical basis. Among these problems, image recognition takes an important place, in particular the classification of multi-dimensional data based on information about textural characteristics. These problems occur in aerospace and seismic monitoring, materials science, medicine and other. We reviewed different approaches for the texture description: statistical, structural, and spectral. We developed a neural network technology for resolving a practical problem of cloud image classification for satellite snapshots from the spectroradiometer MODIS. The cloud texture is described by the statistical characteristics of the GLCM (Gray Level Co- Occurrence Matrix) method. From the range of neural network models that might be applied for image classification, we chose the probabilistic neural network model (PNN) and developed an implementation which performs the classification of the main types and subtypes of clouds. Also, we chose experimentally the optimal architecture and parameters for the PNN model which is used for image classification.

  15. Studying User Footprints in Different Online Social Networks

    OpenAIRE

    Malhotra, Anshu; Totti, Luam; Meira Jr., Wagner; Kumaraguru, Ponnurangam; Almeida, Virgilio

    2013-01-01

    With the growing popularity and usage of online social media services, people now have accounts (some times several) on multiple and diverse services like Facebook, LinkedIn, Twitter and YouTube. Publicly available information can be used to create a digital footprint of any user using these social media services. Generating such digital footprints can be very useful for personalization, profile management, detecting malicious behavior of users. A very important application of analyzing users...

  16. Two types of well followed users in the followership networks of Twitter.

    Directory of Open Access Journals (Sweden)

    Kodai Saito

    Full Text Available In the Twitter blogosphere, the number of followers is probably the most basic and succinct quantity for measuring popularity of users. However, the number of followers can be manipulated in various ways; we can even buy follows. Therefore, alternative popularity measures for Twitter users on the basis of, for example, users' tweets and retweets, have been developed. In the present work, we take a purely network approach to this fundamental question. First, we find that two relatively distinct types of users possessing a large number of followers exist, in particular for Japanese, Russian, and Korean users among the seven language groups that we examined. A first type of user follows a small number of other users. A second type of user follows approximately the same number of other users as the number of follows that the user receives. Then, we compare local (i.e., egocentric followership networks around the two types of users with many followers. We show that the second type, which is presumably uninfluential users despite its large number of followers, is characterized by high link reciprocity, a large number of friends (i.e., those whom a user follows for the followers, followers' high link reciprocity, large clustering coefficient, large fraction of the second type of users among the followers, and a small PageRank. Our network-based results support that the number of followers used alone is a misleading measure of user's popularity. We propose that the number of friends, which is simple to measure, also helps us to assess the popularity of Twitter users.

  17. Collaborative User Network Embedding for Social Recommender Systems

    KAUST Repository

    Zhang, Chuxu

    2017-06-09

    To address the issue of data sparsity and cold-start in recommender system, social information (e.g., user-user trust links) has been introduced to complement rating data for improving the performances of traditional model-based recommendation techniques such as matrix factorization (MF) and Bayesian personalized ranking (BPR). Although effective, the utilization of the explicit user-user relationships extracted directly from such social information has three main limitations. First, it is difficult to obtain explicit and reliable social links. Only a small portion of users indicate explicitly their trusted friends in recommender systems. Second, the “cold-start” users are “cold” not only on rating but also on socializing. There is no significant amount of explicit social information that can be useful for “cold-start” users. Third, an active user can be socially connected with others who have different taste/preference. Direct usage of explicit social links may mislead recommendation. To address these issues, we propose to extract implicit and reliable social information from user feedbacks and identify top-k semantic friends for each user. We incorporate the top-k semantic friends information into MF and BPR frameworks to solve the problems of ratings prediction and items ranking, respectively. The experimental results on three real-world datasets show that our proposed approaches achieve better results than the state-of-the-art MF with explicit social links (with 3.0% improvement on RMSE), and social BPR (with 9.1% improvement on AUC).

  18. Fuzzy logic and neural network technologies

    Science.gov (United States)

    Villarreal, James A.; Lea, Robert N.; Savely, Robert T.

    1992-01-01

    Applications of fuzzy logic technologies in NASA projects are reviewed to examine their advantages in the development of neural networks for aerospace and commercial expert systems and control. Examples of fuzzy-logic applications include a 6-DOF spacecraft controller, collision-avoidance systems, and reinforcement-learning techniques. The commercial applications examined include a fuzzy autofocusing system, an air conditioning system, and an automobile transmission application. The practical use of fuzzy logic is set in the theoretical context of artificial neural systems (ANSs) to give the background for an overview of ANS research programs at NASA. The research and application programs include the Network Execution and Training Simulator and faster training algorithms such as the Difference Optimized Training Scheme. The networks are well suited for pattern-recognition applications such as predicting sunspots, controlling posture maintenance, and conducting adaptive diagnoses.

  19. An Improved User Association Algorithm for MAP–FAPs Heterogeneous Networks

    Directory of Open Access Journals (Sweden)

    Fang Ye

    2016-12-01

    Full Text Available Heterogeneous networks (HetNets give users the opportunity to access different access points(APs, which will simultaneously affect user performance and system performance, so user association in HetNets plays a critical role in enhancing the load balancing and the system sum-throughput of networks. Meanwhile, the incremental sum-throughput currently fails to meet the escalating data demands. Besides, ensuring fairness amongst users constitutes another urgent issue in the radio resource management (RRM of HetNets. What is more, few works consider the maximum service user number constraint in femtocell access points (FAPs. To solve the aforementioned problem, this paper associates users to APs by considering system sum-throughput and fairness at the same time in HetNets under a maximum service user number constraint of FAPs; accordingly, the user association problem is formulated. By releasing constraint, the optimal user association algorithm is obtained by Lagrangian function, and based on this optimal solution, a low complexity suboptimal user association algorithm is proposed. At last, this paper investigates the relationship between system sum-throughput and maximum service user number of FAPs. Numerical simulation results show that the proposed algorithm can improve sum-throughput and fairness at the same time at a specific maximum service user number of FAPs.

  20. E-Center: A Collaborative Platform for Wide Area Network Users

    International Nuclear Information System (INIS)

    Grigoriev, M; DeMar, P; Tierney, B; Lake, A; Metzger, J; Frey, M; Calyam, P

    2012-01-01

    The E-Center is a social collaborative web-based platform for assisting network users in understanding network conditions across network paths of interest to them. It is designed to give a user the necessary tools to isolate, identify, and resolve network performance-related problems. E-Center provides network path information on a link-by-link level, as well as from an end-to-end perspective. In addition to providing current and recent network path data, E-Center is intended to provide a social media environment for them to share issues, ideas, concerns, and problems. The product has a modular design that accommodates integration of other network services that make use of the same network path and performance data.

  1. Attuning speech-enabled interfaces to user and context for inclusive design: Technology, methodology and practice

    NARCIS (Netherlands)

    Neerincx, M.A.; Cremers, A.H.M.; Kessens, J.M.; Leeuwen, D.A. van; Truong, K.P.

    2009-01-01

    This paper presents a methodology to apply speech technology for compensating sensory, motor, cognitive and affective usage difficulties. It distinguishes (1) an analysis of accessibility and technological issues for the identification of context-dependent user needs and corresponding opportunities

  2. Performance Analysis of Diversity-Controlled Multi-User Superposition Transmission for 5G Wireless Networks.

    Science.gov (United States)

    Yeom, Jeong Seon; Chu, Eunmi; Jung, Bang Chul; Jin, Hu

    2018-02-10

    In this paper, we propose a novel low-complexity multi-user superposition transmission (MUST) technique for 5G downlink networks, which allows multiple cell-edge users to be multiplexed with a single cell-center user. We call the proposed technique diversity-controlled MUST technique since the cell-center user enjoys the frequency diversity effect via signal repetition over multiple orthogonal frequency division multiplexing (OFDM) sub-carriers. We assume that a base station is equipped with a single antenna but users are equipped with multiple antennas. In addition, we assume that the quadrature phase shift keying (QPSK) modulation is used for users. We mathematically analyze the bit error rate (BER) of both cell-edge users and cell-center users, which is the first theoretical result in the literature to the best of our knowledge. The mathematical analysis is validated through extensive link-level simulations.

  3. Multiple-users interference alignment base on two-tired heterogeneous networks

    Directory of Open Access Journals (Sweden)

    YANG Jingwen

    2016-04-01

    Full Text Available Interference alignment is a novel interference alignment way,which is popular in interference management of two-tiered heterogeneous networks.Based Interference alignment technique,a two level precoding scheme has been presented to solve the interference in the case of muti-femtocell network coexist with macrocell network.First we define co-layer interference as the interference between femtocell and femtocell,correspondingly,we define cross-layer interference as the interference between macrocell and femtocell,and use precoders at macrocell users and femtocell users respectively.The precoders of macrocell users minimize the cross-layer interference,and output of iteration between precoders of femtocell users and post code of base station bases on mean square error minimization algorithm,which would be used to handle co-layer interference,thus it will reduce interference of femtocell at last and ensure the QoS of femtocell users.

  4. Development of IT-based data communication network technology

    International Nuclear Information System (INIS)

    Hong, Seok Boong; Jeong, K. I.; Yoo, Y. R.

    2010-10-01

    - Developing broadband high-reliability real-time communications technology for NPP - Developing reliability and performance validation technology for communications network - Developing security technology for NPP communications network - Developing field communications network for harsh environment of NPP - International standard registration(Oct. 28, 2009, IEC 61500

  5. SVC-based Multi-user Streamloading for Wireless Networks

    OpenAIRE

    Hosseini, S. Amir; Lu, Zheng; de Veciana, Gustavo; Panwar, Shivendra S.

    2015-01-01

    In this paper, we present an approach for joint rate allocation and quality selection for a novel video streaming scheme called streamloading. Streamloading is a recently developed method for delivering high quality video without violating copyright enforced restrictions on content access for video streaming. In regular streaming services, content providers restrict the amount of viewable video that users can download prior to playback. This approach can cause inferior user experience due to ...

  6. User satisfaction as a political technology in school policy

    DEFF Research Database (Denmark)

    Rasmussen, Palle

    The paper discusses user satisfaction surveys as a policy instrument in education with a focus on local school policy, including the reasons for and the consequences of introducing user surveys in educational policy will be discussed. Empirical examples are drawn mainly from Danish municipalities....

  7. Servicom in the user services of federal univerisyt of technology ...

    African Journals Online (AJOL)

    ... using counting, tables and simple percentages. Finally, the conclusion and recommendations on how best to serve her users, for example by commending the automation and provision of Internet services and urging them to go on and automate all her services. Key words: SERVICOM, User, Services, Univeristy, Library ...

  8. A user credit assessment model based on clustering ensemble for broadband network new media service supervision

    Science.gov (United States)

    Liu, Fang; Cao, San-xing; Lu, Rui

    2012-04-01

    This paper proposes a user credit assessment model based on clustering ensemble aiming to solve the problem that users illegally spread pirated and pornographic media contents within the user self-service oriented broadband network new media platforms. Its idea is to do the new media user credit assessment by establishing indices system based on user credit behaviors, and the illegal users could be found according to the credit assessment results, thus to curb the bad videos and audios transmitted on the network. The user credit assessment model based on clustering ensemble proposed by this paper which integrates the advantages that swarm intelligence clustering is suitable for user credit behavior analysis and K-means clustering could eliminate the scattered users existed in the result of swarm intelligence clustering, thus to realize all the users' credit classification automatically. The model's effective verification experiments are accomplished which are based on standard credit application dataset in UCI machine learning repository, and the statistical results of a comparative experiment with a single model of swarm intelligence clustering indicates this clustering ensemble model has a stronger creditworthiness distinguishing ability, especially in the aspect of predicting to find user clusters with the best credit and worst credit, which will facilitate the operators to take incentive measures or punitive measures accurately. Besides, compared with the experimental results of Logistic regression based model under the same conditions, this clustering ensemble model is robustness and has better prediction accuracy.

  9. A random access scheme with physical-layer network coding and user identification

    NARCIS (Netherlands)

    Goseling, Jasper

    2014-01-01

    A slotted random access scheme is proposed that is based on physical-layer network coding. The scheme uses signature codes that enable the receiver to detect which users are active in each round and which linear combination of pckets is received. Feedback enables in each round, one of the users to

  10. Distinctive roles of lead users and opinion leaders in the social networks of schoolchildren

    DEFF Research Database (Denmark)

    Kratzer, Jan; Lettl, Christopher

    2009-01-01

    Prior research has shown that both lead users and opinion leaders may propel the diffusion of innovation. This raises the question of whether lead users and opinion leaders are positioned similarly in social networks, which we addressed using a sample of 23 school classes consisting of 537 children...

  11. Network Gateway Technology: The Issue of Redundancy towards ...

    African Journals Online (AJOL)

    The Internet has provided advancement in the areas of network and networking facilities. Everyone connected to the Internet is concerned about two basic things: the availability of network services and the speed of the network. Network gateway redundancy technology falls within these categories and happens to be one of ...

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

    DEFF Research Database (Denmark)

    Hillmann, Robert; Trier, Matthias

    2012-01-01

    by analyzing sentiment exchange within social networks from an ego-network perspective. We draw from research on social influence and social attachment to develop theories of node polarization, balance effects and sentiment mirroring within communication dyads. Our empirical analysis covers a multitude...

  13. Water Network Tool for Resilience (WNTR) User Manual

    Science.gov (United States)

    The Water Network Tool for Resilience (WNTR) is a new Python package designed to simulate and analyze resilience of water distribution networks to a variety of disaster scenarios. WNTR can help water utilities to explore the capacity of their systems to handle disasters and gui...

  14. Social Networks Users: Fear of Missing out in Preservice Teachers

    Science.gov (United States)

    Gezgin, Deniz Mertkan; Hamutoglu, Nazire Burcin; Gemikonakli, Orhan; Raman, Ilhan

    2017-01-01

    As mobile computing and smartphones become an integrated part of our lives, the time individuals spend on social networks has significantly increased. Moreover, a link has been established between the uncontrolled use of social networks to the development of undesirable habits and behaviors including addictions. One such behavior, namely, fear of…

  15. 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.

  16. fraud detection in mobile communications networks using user

    African Journals Online (AJOL)

    DEPT OF AGRICULTURAL ENGINEERING

    Fraud in telecommunications networks can be characterized by fraud conditions, which essen- tially describe how the fraudster gained the illegitimate access to the network. This study concentrated on the detection methodologies based on the calling activity. This is divided into two categories of absolute and differential.

  17. Water Network Tool for Resilience (WNTR) User Manual -

    Science.gov (United States)

    The Water Network Tool for Resilience (WNTR) is a new Python package designed to simulate and analyze resilience of water distribution networks to a variety of disaster scenarios. WNTR can help water utilities to explore the capacity of their systems to handle disasters and gui...

  18. The Users' Views on Different Types of Instructional Materials Provided in Virtual Reality Technologies

    Science.gov (United States)

    Yildirim, Gürkan

    2017-01-01

    Today, it is seen that developing technologies are tried to be used continuously in the learning environments. These technologies have rapidly been diversifying and changing. Recently, virtual reality technology has become one of the technologies that experts have often been dwelling on. The present research tries to determine users' opinions and…

  19. 76 FR 58020 - Prescription Drug User Fee Act IV Information Technology Plan

    Science.gov (United States)

    2011-09-19

    ...] Prescription Drug User Fee Act IV Information Technology Plan AGENCY: Food and Drug Administration, HHS. ACTION... information technology (IT) plan entitled ``PDUFA IV Information Technology Plan'' (updated plan) to achieve... Information Technology Plan.'' This plan will meet one of the performance goals agreed to under the 2007...

  20. Open|SpeedShop Graphical User Interface Technology, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose to create a new graphical user interface (GUI) for an existing parallel application performance and profiling tool, Open|SpeedShop. The current GUI has...

  1. Open|SpeedShop Graphical User Interface Technology Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose to create a new graphical user interface (GUI) for an existing parallel application performance and profiling tool, Open|SpeedShop. The current GUI has...

  2. Threshold Based Opportunistic Scheduling of Secondary Users in Underlay Cognitive Radio Networks

    KAUST Repository

    Song, Yao

    2011-12-01

    In underlay cognitive radio networks, secondary users can share the spectrum with primary users as long as the interference caused by the secondary users to primary users is below a certain predetermined threshold. It is reasonable to assume that there is always a large pool of secondary users trying to access the channel, which can be occupied by only one secondary user at a given time. As a result, a multi-user scheduling problem arises among the secondary users. In this thesis, by manipulating basic schemes based on selective multi-user diversity, normalized thresholding, transmission power control, and opportunistic round robin, we propose and analyze eight scheduling schemes of secondary users in an underlay cognitive radio set-up. The system performance of these schemes is quantified by using various performance metrics such as the average system capacity, normalized average feedback load, scheduling outage probability, and system fairness of access. In our proposed schemes, the best user out of all the secondary users in the system is picked to transmit at each given time slot in order to maximize the average system capacity. Two thresholds are used in the two rounds of the selection process to determine the best user. The first threshold is raised by the power constraint from the primary user. The second threshold, which can be adjusted by us, is introduced to reduce the feedback load. The overall system performance is therefore dependent on the choice of these two thresholds and the number of users in the system given the channel conditions for all the users. In this thesis, by deriving analytical formulas and presenting numerical examples, we try to provide insights of the relationship between the performance metrics and the involved parameters including two selection thresholds and the number of active users in the system, in an effort to maximize the average system capacity as well as satisfy the requirements of scheduling outage probability and

  3. Application of UDWDM technology in FTTH networks

    Science.gov (United States)

    Lamperski, Jan; Stepczak, Piotr

    2015-12-01

    In the paper we presented results of investigation of an original ultra dense wavelength division technology based on optical comb generator and its implementation for FTTH networks. The optical comb generator used a ring configuration with an acousto-optic frequency shifter (AOFS) which ensured obtaining very stable optical carrier frequency distances. Properties of an optical comb generator module determined stability of the UDWDM transmitter. Key properties of a selective components based on all fiber Fabry-Perot resonant cavity were presented. Operation of direct and coherent detection DWDM systems were shown. New configurations of FTTH UDWDM architecture have been proposed.

  4. Estimating User Influence in Online Social Networks Subject to Information Overload

    Science.gov (United States)

    Li, Pei; Sun, Yunchuan; Chen, Yingwen; Tian, Zhi

    2014-11-01

    Online social networks have attracted remarkable attention since they provide various approaches for hundreds of millions of people to stay connected with their friends. Due to the existence of information overload, the research on diffusion dynamics in epidemiology cannot be adopted directly to that in online social networks. In this paper, we consider diffusion dynamics in online social networks subject to information overload, and model the information-processing process of a user by a queue with a batch arrival and a finite buffer. We use the average number of times a message is processed after it is generated by a given user to characterize the user influence, which is then estimated through theoretical analysis for a given network. We validate the accuracy of our estimation by simulations, and apply the results to study the impacts of different factors on the user influence. Among the observations, we find that the impact of network size on the user influence is marginal while the user influence decreases with assortativity due to information overload, which is particularly interesting.

  5. Satellite Network Performance Measurements Using Simulated Multi-User Internet Traffic

    Science.gov (United States)

    Kruse, Hans; Allman, Mark; Griner, Jim; Ostermann, Shawn; Helvey, Eric

    1999-01-01

    As a number of diverse satellite systems (both Low Earth Orbit and Geostationary systems) are being designed and deployed, it becomes increasingly important to be able to test these systems under realistic traffic loads. While software simulations can provide valuable input into the system design process, it is crucial that the physical system be tested so that actual network devices can be employed and tuned. These tests need to utilize traffic patterns that closely mirror the expected user load, without the need to actually deploy an end-user network for the test. In this paper, we present trafgen. trafgen uses statistical information about the characteristics of sampled network traffic to emulate the same type of traffic over the test network. This paper compares sampled terrestrial network traffic with emulated satellite network traffic over the NASA ACTS satellite.

  6. A User Authentication Scheme Based on Elliptic Curves Cryptography for Wireless Ad Hoc Networks

    Science.gov (United States)

    Chen, Huifang; Ge, Linlin; Xie, Lei

    2015-01-01

    The feature of non-infrastructure support in a wireless ad hoc network (WANET) makes it suffer from various attacks. Moreover, user authentication is the first safety barrier in a network. A mutual trust is achieved by a protocol which enables communicating parties to authenticate each other at the same time and to exchange session keys. For the resource-constrained WANET, an efficient and lightweight user authentication scheme is necessary. In this paper, we propose a user authentication scheme based on the self-certified public key system and elliptic curves cryptography for a WANET. Using the proposed scheme, an efficient two-way user authentication and secure session key agreement can be achieved. Security analysis shows that our proposed scheme is resilient to common known attacks. In addition, the performance analysis shows that our proposed scheme performs similar or better compared with some existing user authentication schemes. PMID:26184224

  7. A User Authentication Scheme Based on Elliptic Curves Cryptography for Wireless Ad Hoc Networks.

    Science.gov (United States)

    Chen, Huifang; Ge, Linlin; Xie, Lei

    2015-07-14

    The feature of non-infrastructure support in a wireless ad hoc network (WANET) makes it suffer from various attacks. Moreover, user authentication is the first safety barrier in a network. A mutual trust is achieved by a protocol which enables communicating parties to authenticate each other at the same time and to exchange session keys. For the resource-constrained WANET, an efficient and lightweight user authentication scheme is necessary. In this paper, we propose a user authentication scheme based on the self-certified public key system and elliptic curves cryptography for a WANET. Using the proposed scheme, an efficient two-way user authentication and secure session key agreement can be achieved. Security analysis shows that our proposed scheme is resilient to common known attacks. In addition, the performance analysis shows that our proposed scheme performs similar or better compared with some existing user authentication schemes.

  8. Injection Drug Users' Involvement In Drug Economy: Dynamics of Sociometric and Egocentric Social Networks.

    Science.gov (United States)

    Yang, Cui; Latkin, Carl; Muth, Stephen Q; Rudolph, Abby

    2013-07-01

    The purpose of this analysis was to examine the effect of social network cohesiveness on drug economy involvement, and to test whether this relationship is mediated by drug support network size in a sample of active injection drug users. Involvement in the drug economy was defined by self-report of participation in at least one of the following activities: selling drugs, holding drugs or money for drugs, providing street security for drug sellers, cutting/packaging/cooking drugs, selling or renting drug paraphernalia (e.g., pipes, tools, rigs), and injecting drugs in others' veins. The sample consists of 273 active injection drug users in Baltimore, Maryland who reported having injected drugs in the last 6 months and were recruited through either street outreach or by their network members. Egocentric drug support networks were assessed through a social network inventory at baseline. Sociometric networks were built upon the linkages by selected matching characteristics, and k-plex rank was used to characterize the level of cohesiveness of the individual to others in the social network. Although no direct effect was observed, structural equation modeling indicated k-plex rank was indirectly associated with drug economy involvement through drug support network size. These findings suggest the effects of large-scale sociometric networks on injectors' drug economy involvement may occur through their immediate egocentric networks. Future harm reduction programs for injection drug users (IDUs) should consider providing programs coupled with economic opportunities to those drug users within a cohesive network subgroup. Moreover, individuals with a high connectivity to others in their network may be optimal individuals to train for diffusing HIV prevention messages.

  9. A user exposure based approach for non-structural road network vulnerability analysis

    OpenAIRE

    Jin, Lei; Wang, Haizhong; Xie, Binglei; Yu, Le; Liu, Lin

    2017-01-01

    Aiming at the dense urban road network vulnerability without structural negative consequences, this paper proposes a novel non-structural road network vulnerability analysis framework. Three aspects of the framework are mainly described: (i) the rationality of non-structural road network vulnerability, (ii) the metrics for negative consequences accounting for variant road conditions, and (iii) the introduction of a new vulnerability index based on user exposure. Based on the proposed methodol...

  10. Policy gaps and technological deficiencies in social networking environments: Implications for information sharing

    Directory of Open Access Journals (Sweden)

    Stephen M. Mutula

    2013-06-01

    Full Text Available Background: With the growing adoption and acceptance of social networking, there are increased concerns about the violation of the users’ legitimate rights such as privacy, confidentiality, trust, security, safety, content ownership, content accuracy, integrity, access and accessibility to computer and digital networks amongst others.Objectives: The study sought to investigate the following research objectives to: (1 describe the types of social networks, (2 examine global penetration of the social networks, (3 outline the users’ legitimate rights that must be protected in the social networking sites (SNS, (4 determine the methods employed by SNS to protect the users’ legitimate rights and (5 identify the policy gaps and technological deficiencies in the protection of the users’ legitimate rights in the SNS.Method: A literature survey and content analysis of the SNS user policies were used to address objective four and objective five respectively.Results: The most actively used sites were Facebook and Twitter. Asian markets were leading in participation and in creating content than any other region. Business, education, politics and governance sectors were actively using social networking sites. Social networking sites relied upon user trust and internet security features which however, were inefficient and inadequate.Conclusion: Whilst SNS were impacting people of varying ages and of various professional persuasions, there were increased concerns about the violation and infringement of the users’ legitimate rights. Reliance on user trust and technological security features SNS to protect the users’ legitimate rights seemed ineffectual and inadequate.

  11. Modeling users' activity on Twitter networks: validation of Dunbar's number

    Science.gov (United States)

    Goncalves, Bruno; Perra, Nicola; Vespignani, Alessandro

    2012-02-01

    Microblogging and mobile devices appear to augment human social capabilities, which raises the question whether they remove cognitive or biological constraints on human communication. In this paper we analyze a dataset of Twitter conversations collected across six months involving 1.7 million individuals and test the theoretical cognitive limit on the number of stable social relationships known as Dunbar's number. We find that the data are in agreement with Dunbar's result; users can entertain a maximum of 100-200 stable relationships. Thus, the ``economy of attention'' is limited in the online world by cognitive and biological constraints as predicted by Dunbar's theory. We propose a simple model for users' behavior that includes finite priority queuing and time resources that reproduces the observed social behavior.

  12. Modeling users' activity on twitter networks: validation of Dunbar's number.

    Directory of Open Access Journals (Sweden)

    Bruno Gonçalves

    Full Text Available Microblogging and mobile devices appear to augment human social capabilities, which raises the question whether they remove cognitive or biological constraints on human communication. In this paper we analyze a dataset of Twitter conversations collected across six months involving 1.7 million individuals and test the theoretical cognitive limit on the number of stable social relationships known as Dunbar's number. We find that the data are in agreement with Dunbar's result; users can entertain a maximum of 100-200 stable relationships. Thus, the 'economy of attention' is limited in the online world by cognitive and biological constraints as predicted by Dunbar's theory. We propose a simple model for users' behavior that includes finite priority queuing and time resources that reproduces the observed social behavior.

  13. Elastic optical networks architectures, technologies, and control

    CERN Document Server

    Velasco, Luis

    2016-01-01

    This book addresses challenges and potential solutions surrounding the dramatic yearly increases in bandwidth demand. The editors discuss the predicament surrounding current growth, which is predicted to continue because of the proliferation of disruptive, high bandwidth applications like video and cloud applications. They also discuss that in addition to growth, traffic will become much more dynamic, both in time and direction. The contributors show how large changes in traffic magnitude during a 24-hour period can be observed, as day-time business users have very different demands to evening-time residential customers, and how this plays into addressing future challenges. In addition, they discuss potential solutions for the issues surrounding situations where multiple content and cloud service providers offer competing services, causing the traffic direction to become more dynamic. The contributors discuss that although the WDM transponder technology can be upgraded to 100Gb/s in the short to medium term, ...

  14. Network intrusion detector: NID user`s guide V 1.0

    Energy Technology Data Exchange (ETDEWEB)

    Palasek, R. [ed.

    1994-04-01

    The NID suite of software tools was developed to help detect and analyze intrusive behavior over networks. NID combines and uses three techniques of intrusion detection: attack signature recognition, anomaly detection, and a vulnerability risk model. The authors have found from experience that the signature recognition component has been the most effective in detecting network based attacks. The underlying assumption of NID is that there is a security domain that you are interested in protecting. NID monitors traffic that crosses the boundary of that domain, looking for signs of intrusion and abnormal activity.

  15. Network Gateway Technology: The Issue of Redundancy towards ...

    African Journals Online (AJOL)

    Everyone connected to the Internet is concerned about two basic things: the availability of network services and the speed of the network. Network gateway redundancy technology falls within these categories and happens to be one of the newest technologies which only few companies, such as mobile companies and ...

  16. Conference on "Mathematical Technology of Networks"

    CERN Document Server

    2015-01-01

    Bringing together leading researchers in the fields of functional analysis, mathematical physics and graph theory, as well as natural scientists using networks as a tool in their own research fields, such as neuroscience and machine learning, this volume presents recent advances in functional, analytical, probabilistic, and spectral aspects in the study of graphs, quantum graphs, and complex networks. The contributors to this volume explore the interplay between theoretical and applied aspects of discrete and continuous graphs. Their work helps to close the gap between different avenues of research on graphs, including metric graphs and ramified structures. All papers were presented at the conference "Mathematical Technology of Networks," held December 4–7, 2013 at the Zentrum für interdisziplinäre Forschung (ZiF) in Bielefeld, Germany, and are supplemented with detailed figures illustrating both abstract concepts as well as their real-world applications. Dynamical models on graphs or random graphs a...

  17. Ad hoc laser networks component technology for modular spacecraft

    Science.gov (United States)

    Huang, Xiujun; Shi, Dele; Shen, Jingshi

    2017-10-01

    Distributed reconfigurable satellite is a new kind of spacecraft system, which is based on a flexible platform of modularization and standardization. Based on the module data flow analysis of the spacecraft, this paper proposes a network component of ad hoc Laser networks architecture. Low speed control network with high speed load network of Microwave-Laser communication mode, no mesh network mode, to improve the flexibility of the network. Ad hoc Laser networks component technology was developed, and carried out the related performance testing and experiment. The results showed that ad hoc Laser networks components can meet the demand of future networking between the module of spacecraft.

  18. An Automatic User Grouping Model for a Group Recommender System in Location-Based Social Networks

    Directory of Open Access Journals (Sweden)

    Elahe Khazaei

    2018-02-01

    Full Text Available Spatial group recommendation refers to suggesting places to a given set of users. In a group recommender system, members of a group should have similar preferences in order to increase the level of satisfaction. Location-based social networks (LBSNs provide rich content, such as user interactions and location/event descriptions, which can be leveraged for group recommendations. In this paper, an automatic user grouping model is introduced that obtains information about users and their preferences through an LBSN. The preferences of the users, proximity of the places the users have visited in terms of spatial range, users’ free days, and the social relationships among users are extracted automatically from location histories and users’ profiles in the LBSN. These factors are combined to determine the similarities among users. The users are partitioned into groups based on these similarities. Group size is the key to coordinating group members and enhancing their satisfaction. Therefore, a modified k-medoids method is developed to cluster users into groups with specific sizes. To evaluate the efficiency of the proposed method, its mean intra-cluster distance and its distribution of cluster sizes are compared to those of general clustering algorithms. The results reveal that the proposed method compares favourably with general clustering approaches, such as k-medoids and spectral clustering, in separating users into groups of a specific size with a lower mean intra-cluster distance.

  19. Enhancing the Gaming Experience Using 3D Spatial User Interface Technologies.

    Science.gov (United States)

    Kulshreshth, Arun; Pfeil, Kevin; LaViola, Joseph J

    2017-01-01

    Three-dimensional (3D) spatial user interface technologies have the potential to make games more immersive and engaging and thus provide a better user experience. Although technologies such as stereoscopic 3D display, head tracking, and gesture-based control are available for games, it is still unclear how their use affects gameplay and if there are any user performance benefits. The authors have conducted several experiments on these technologies in game environments to understand how they affect gameplay and how we can use them to optimize the gameplay experience.

  20. User perceptions regarding sanitation technologies in South Africa

    CSIR Research Space (South Africa)

    Duncker, Louiza C

    2014-09-01

    Full Text Available , technical aspects and social dynamics are the cornerstones for the long-term operation of facilities and the sustainability of services delivery. This paper shows some results of spot check assessments and will draw the attention to the user issues...

  1. Segmenting the social networking sites users: An empirical study

    NARCIS (Netherlands)

    Lorenzo-Romero, C.; Constantinides, Efthymios; Alarcon-del-Amo, M.d.C.

    2012-01-01

    The growth of social networking sites (SNS) presents businesses and marketers with risks and challenges. Customers become sophisticated, empowered and increasingly involved in shaping of the marketing offer. Marketers are becoming aware of the threat of losing control over their message but also

  2. Dynamics of user networks in on-line electronic auctions

    Czech Academy of Sciences Publication Activity Database

    Slanina, František

    2014-01-01

    Roč. 17, č. 1 (2014), "1450002-1"-"1450002-14" ISSN 0219-5259 R&D Projects: GA MŠk OC09078 Institutional support: RVO:68378271 Keywords : networks * random graphs * dynamics Subject RIV: BE - Theoretical Physics Impact factor: 0.968, year: 2014

  3. Securing Collaborative Spectrum Sensing against Untrustworthy Secondary Users in Cognitive Radio Networks

    Science.gov (United States)

    Wang, Wenkai; Li, Husheng; Sun, Yan(Lindsay); Han, Zhu

    2009-12-01

    Cognitive radio is a revolutionary paradigm to migrate the spectrum scarcity problem in wireless networks. In cognitive radio networks, collaborative spectrum sensing is considered as an effective method to improve the performance of primary user detection. For current collaborative spectrum sensing schemes, secondary users are usually assumed to report their sensing information honestly. However, compromised nodes can send false sensing information to mislead the system. In this paper, we study the detection of untrustworthy secondary users in cognitive radio networks. We first analyze the case when there is only one compromised node in collaborative spectrum sensing schemes. Then we investigate the scenario that there are multiple compromised nodes. Defense schemes are proposed to detect malicious nodes according to their reporting histories. We calculate the suspicious level of all nodes based on their reports. The reports from nodes with high suspicious levels will be excluded in decision-making. Compared with existing defense methods, the proposed scheme can effectively differentiate malicious nodes and honest nodes. As a result, it can significantly improve the performance of collaborative sensing. For example, when there are 10 secondary users, with the primary user detection rate being equal to 0.99, one malicious user can make the false alarm rate [InlineEquation not available: see fulltext.] increase to 72%. The proposed scheme can reduce it to 5%. Two malicious users can make [InlineEquation not available: see fulltext.] increase to 85% and the proposed scheme reduces it to 8%.

  4. PREFACE: Complex Networks: from Biology to Information Technology

    Science.gov (United States)

    Barrat, A.; Boccaletti, S.; Caldarelli, G.; Chessa, A.; Latora, V.; Motter, A. E.

    2008-06-01

    The field of complex networks is one of the most active areas in contemporary statistical physics. Ten years after seminal work initiated the modern study of networks, interest in the field is in fact still growing, as indicated by the ever increasing number of publications in network science. The reason for such a resounding success is most likely the simplicity and broad significance of the approach that, through graph theory, allows researchers to address a variety of different complex systems within a common framework. This special issue comprises a selection of contributions presented at the workshop 'Complex Networks: from Biology to Information Technology' held in July 2007 in Pula (Cagliari), Italy as a satellite of the general conference STATPHYS23. The contributions cover a wide range of problems that are currently among the most important questions in the area of complex networks and that are likely to stimulate future research. The issue is organised into four sections. The first two sections describe 'methods' to study the structure and the dynamics of complex networks, respectively. After this methodological part, the issue proceeds with a section on applications to biological systems. The issue closes with a section concentrating on applications to the study of social and technological networks. The first section, entitled Methods: The Structure, consists of six contributions focused on the characterisation and analysis of structural properties of complex networks: The paper Motif-based communities in complex networks by Arenas et al is a study of the occurrence of characteristic small subgraphs in complex networks. These subgraphs, known as motifs, are used to define general classes of nodes and their communities by extending the mathematical expression of the Newman-Girvan modularity. The same line of research, aimed at characterising network structure through the analysis of particular subgraphs, is explored by Bianconi and Gulbahce in Algorithm

  5. Impact of Entertainment Motivational Drivers on User Acceptance of Online Social Network Banner Advertising: A Gratification Perspective

    Directory of Open Access Journals (Sweden)

    Mir Imran Anwar

    2017-05-01

    Full Text Available Social media has phenomenally changed the communication landscape. Particularly social network sites have received enormous popularity and user acceptance globally. The business model of many social network sites is based on advertising. The survival of these social network sites depends on the user acceptance of advertising appearing on these websites. Users usually accept the advertising which is consistent with their motivations for using social network sites. The current study examines the underlying dimensions of entertainment motivation for using social network sites and their impact on user acceptance of social network advertising. Analysis of data from 450 university students show entertainment motivation for using social network sites a multidimensional (SNSs construct consisting of enjoyment, social escapism, relaxation and pass time factors. Furthermore, the results exhibit that SNSs entertainment motivation partially impacts user acceptance of social network advertising.

  6. The German competence network on nuclear technology

    International Nuclear Information System (INIS)

    Kuczera, B.; Fritz, P.

    2004-01-01

    Full text: The present German energy policy is based on the phase-out of nuclear electricity generation, which means that the last of the currently operating eighteen German nuclear power plants will run until about 2022. While the plants will be shut down one after the other, decommissioning will start together with interim storage of the radioactive waste. The safe waste disposal in a final repository is planned to start around 2030 and may take another two decades, i.e., in Germany nuclear competence is further needed, at least until the mid of this century. Against this background, a high-ranking commission under the direction of the Federal Ministry of Economy and Technology evaluated the publicly funded nuclear safety related research and development (R and D) activities in Germany. One of the recommendations made by the commission was the foundation of a Competence Network on Nuclear Technology for an optimum coordination of the remaining nuclear activities including aspects of future human resources in this area. This Network was established in March 2000 with the following member institutions: Research Centre Juelich, Research Centre Karlsruhe, Research Centre Rossendorf and the Gesellschaft fuer Anlagen- und Reaktorsicherheit (GRS) in Munich and their neighbouring Technical Universities. The strategic objectives of the Competence Network include: Trend investigations on job development and on university education capacities in the nuclear technology sector; Enhanced cooperation of the Research Centres with universities in the nuclear field and support of international education initiatives (e.g. ENEN, WNU); Coordination and bundling of the activities in publicly funded reactor safety and waste management R and D programmes; Support of qualified young scientists and engineers (pre-doctoral students) - also by third-party funds; Participation in and collaboration with international projects and activities for advancements of international nuclear safety

  7. Cryptanalysis and Improvement of the Robust User Authentication Scheme for Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Yung-Cheng Lee

    2012-10-01

    Full Text Available Wireless sensor networks are widely used in industrial process control, human health care, environmental control, vehicular tracking and battlefield surveillance, etc. A wireless sensor network consists of lots of sensor nodes and a gateway node. The sensor node usually communicates with the gateway node and users over an ad hoc wireless network. However, due to the open environments, the wireless sensor networks are vulnerable to variety of security threats. Thus, it is a critical issue to adopt a suitable authentication mechanism for wireless sensor networks to enhance security. In 2009, Vaidya et al. proposed a robust user authentication schemes for wireless sensor networks. In this article, we will show that their scheme is vulnerable to the guessing attack and the impersonation attack. Since it needs a secure channel for communications in password changing phase, their scheme is also inconvenient and expensive for users to update passwords. We also propose an improved scheme to remedy the flaws. The improved scheme withstands the replay attack and off-line guessing attack, and the users can freely update their passwords via public channels.

  8. Information and communication technology and user knowledge-driven innovation in services

    Directory of Open Access Journals (Sweden)

    Hong Y. Park

    2015-12-01

    Full Text Available User knowledge has been an important source of novel product development and innovation, but gathering accurate user knowledge has been time consuming and difficult because user knowledge is tacit and globally dispersed. However, information and communication technology can expand the boundaries by making user knowledge easier and less expensive to access. Structures and organizations are emerging to perform the task of user information gathering. This paper examines the nature of user knowledge and the emergence of a new system/structure for user knowledge gathering and user involvement in innovation. Three case studies of business innovation in three different organizations illustrate the ways that the organization matches the type of innovation with the characteristics of user knowledge. User involvement can occur either through direct input or via feedback provided after customers received services. User input can also be either proactive or reactive. User knowledge is often employed to monitor service workers also, which has significantly contributed to recent improvement in service quality. The cases presented support our proposition.

  9. Proposal for Implementing Multi-User Database (MUD) Technology in an Academic Library.

    Science.gov (United States)

    Filby, A. M. Iliana

    1996-01-01

    Explores the use of MOO (multi-user object oriented) virtual environments in academic libraries to enhance reference services. Highlights include the development of multi-user database (MUD) technology from gaming to non-recreational settings; programming issues; collaborative MOOs; MOOs as distinguished from other types of virtual reality; audio…

  10. A survey on the wireless sensor network technology

    International Nuclear Information System (INIS)

    Kim, Jae Hee; Jun, Hyeong Seop; Lee, Jae Cheol; Choi, Yoo Rak

    2007-12-01

    Wireless sensor technology is required in the safety inspection for safety-critical unit of nuclear power plant. This report describes wireless sensor technology related with the project named 'Development of a remote care system of NPP components based on the network and safety database'. This report includes contents of methodology and status of sensor network construction, status of zigbee sensor network, problem of security and sensor battery. Energy harvesting technology will be mentioned on the next report

  11. EXPERIMEDIA: Innovate in New Media - a multi-venue experimentation service supporting technology innovation thrugh new forms of social interaction and user experience

    OpenAIRE

    Boniface, M.J.; Modafferi, Stefano; Voulodimos, Athanasios; Salama, David; Murg, Sandra

    2014-01-01

    New media applications and services are revolutionising social interaction and user experience in both society and in wide ranging industry sectors. The rapid emergence of pervasive human and environment sensing technologies, novel immersive presentation devices and high performance, globally connected network and cloud infrastructures is generating huge opportunities for application providers, service provider and content providers. These new applications are driving convergence across devic...

  12. A user exposure based approach for non-structural road network vulnerability analysis.

    Directory of Open Access Journals (Sweden)

    Lei Jin

    Full Text Available Aiming at the dense urban road network vulnerability without structural negative consequences, this paper proposes a novel non-structural road network vulnerability analysis framework. Three aspects of the framework are mainly described: (i the rationality of non-structural road network vulnerability, (ii the metrics for negative consequences accounting for variant road conditions, and (iii the introduction of a new vulnerability index based on user exposure. Based on the proposed methodology, a case study in the Sioux Falls network which was usually threatened by regular heavy snow during wintertime is detailedly discussed. The vulnerability ranking of links of Sioux Falls network with respect to heavy snow scenario is identified. As a result of non-structural consequences accompanied by conceivable degeneration of network, there are significant increases in generalized travel time costs which are measurements for "emotionally hurt" of topological road network.

  13. Smoke Screener or Straight Shooter: Detecting Elite Sybil Attacks in User-Review Social Networks

    OpenAIRE

    Zheng, Haizhong; Xue, Minhui; Lu, Hao; Hao, Shuang; Zhu, Haojin; Liang, Xiaohui; Ross, Keith

    2017-01-01

    Popular User-Review Social Networks (URSNs)---such as Dianping, Yelp, and Amazon---are often the targets of reputation attacks in which fake reviews are posted in order to boost or diminish the ratings of listed products and services. These attacks often emanate from a collection of accounts, called Sybils, which are collectively managed by a group of real users. A new advanced scheme, which we term elite Sybil attacks, recruits organically highly-rated accounts to generate seemingly-trustwor...

  14. Functional Assessment for Human-Computer Interaction: A Method for Quantifying Physical Functional Capabilities for Information Technology Users

    Science.gov (United States)

    Price, Kathleen J.

    2011-01-01

    The use of information technology is a vital part of everyday life, but for a person with functional impairments, technology interaction may be difficult at best. Information technology is commonly designed to meet the needs of a theoretical "normal" user. However, there is no such thing as a "normal" user. A user's capabilities will vary over…

  15. The Impact of Wireless Phone Technology on Users in Nigeria

    Science.gov (United States)

    Ezenezi, Robins E.

    2010-01-01

    Studies have shown that with the increasing diffusion of cell phones in Nigeria have come with problems such as network congestion, service inefficiencies, rising costs, and increased taxes. The purpose of this study was to examine and explore which, if any, sociopersonal variables (theft of handsets, educational levels, security risk) and…

  16. World-Wide Standardized Seismograph Network: a data users guide

    Science.gov (United States)

    Peterson, Jon R.; Hutt, Charles R.

    2014-01-01

    The purpose of this report, which is based on an unpublished draft prepared in the 1970s, is to provide seismologists with the information they may need to use the WWSSN data set as it becomes available in a more easily accessible and convenient format on the Internet. The report includes a description of the WWSSN network, station facilities, operations and instrumentation, a derivation of the instrument transfer functions, tables of transfer functions, a description of calibration techniques, and a description of a method used to determine important instrument constants using recorded calibration data.

  17. The Impact of Technology on Users and the Workplace.

    Science.gov (United States)

    Chan, Susy S.

    1999-01-01

    Identifies four trends in corporate information technology and applies them to the academic workplace and institutional research. Trends are (1) knowledge management, (2) enterprise resource planning, (3) data warehousing, and (4) electronic commerce. (Author/DB)

  18. Low-Feedback Opportunistic Scheduling Schemes for Wireless Networks with Heterogenous Users

    KAUST Repository

    Rashid, Faraan

    2012-07-01

    Efficient implementation of resource sharing strategies in a multi-user wireless environment can improve the performance of a network significantly. In this thesis we study various scheduling strategies for wireless networks and handle the problem of opportunistically scheduling transmissions using channel aware schemes. First we propose a scheme that can handle users with asymmetric channel conditions and is opportunistic in the sense that it exploits the multi-user diversity of the network. The scheme requires the users to have a priori knowledge of their channel distributions. The associated overhead is limited meaning it offers reduced feedback load, that does not scale with the increasing number of users. The main technique used to shrink the feedback load is the contention based distributed implementation of a splitting algorithm that does not require explicit feedback to the scheduler from every user. The users find the best among themselves, in a distributed manner, while requiring just a ternary broadcast feedback from the scheduler at the end of each mini-slot. In addition, it can also handle fairness constraints in time and throughput to various degrees. Next we propose another opportunistic scheduler that offers most of the benefits of the previously proposed scheme but is more practical because it can also handle heterogenous users whose channel distributions are unknown. This new scheme actually reduces the complexity and is also more robust for changing traffic patterns. Finally we extend both these schemes to the scenario where there are fixed thresholds, this enables us to handle opportunistic scheduling in practical systems that can only transmit over finite number of discrete rates with the additional benefit that full feedback session, even from the selected user, is never required.

  19. On the Existence of Optimal Taxes for Network Congestion Games with Heterogeneous Users

    Science.gov (United States)

    Fotakis, Dimitris; Karakostas, George; Kolliopoulos, Stavros G.

    We consider network congestion games in which a finite number of non-cooperative users select paths. The aim is to mitigate the inefficiency caused by the selfish users by introducing taxes on the network edges. A tax vector is strongly (weakly)-optimal if all (at least one of) the equilibria in the resulting game minimize(s) the total latency. The issue of designing optimal tax vectors for selfish routing games has been studied extensively in the literature. We study for the first time taxation for networks with atomic users which have unsplittable traffic demands and are heterogeneous, i.e., have different sensitivities to taxes. On the positive side, we show the existence of weakly-optimal taxes for single-source network games. On the negative side, we show that the cases of homogeneous and heterogeneous users differ sharply as far as the existence of strongly-optimal taxes is concerned: there are parallel-link games with linear latencies and heterogeneous users that do not admit strongly-optimal taxes.

  20. Ethernet access network based on free-space optic deployment technology

    Science.gov (United States)

    Gebhart, Michael; Leitgeb, Erich; Birnbacher, Ulla; Schrotter, Peter

    2004-06-01

    The satisfaction of all communication needs from single households and business companies over a single access infrastructure is probably the most challenging topic in communications technology today. But even though the so-called "Last Mile Access Bottleneck" is well known since more than ten years and many distribution technologies have been tried out, the optimal solution has not yet been found and paying commercial access networks offering all service classes are still rare today. Conventional services like telephone, radio and TV, as well as new and emerging services like email, web browsing, online-gaming, video conferences, business data transfer or external data storage can all be transmitted over the well known and cost effective Ethernet networking protocol standard. Key requirements for the deployment technology driven by the different services are high data rates to the single customer, security, moderate deployment costs and good scalability to number and density of users, quick and flexible deployment without legal impediments and high availability, referring to the properties of optical and wireless communication. We demonstrate all elements of an Ethernet Access Network based on Free Space Optic distribution technology. Main physical parts are Central Office, Distribution Network and Customer Equipment. Transmission of different services, as well as configuration, service upgrades and remote control of the network are handled by networking features over one FSO connection. All parts of the network are proven, the latest commercially available technology. The set up is flexible and can be adapted to any more specific need if required.

  1. User interface on networked workstations for MFTF plasma diagnostic instruments

    International Nuclear Information System (INIS)

    Renbarger, V.L.; Balch, T.R.

    1985-01-01

    A network of Sun-2/170 workstations is used to provide an interface to the MFTF-B Plasma Diagnostics System at Lawrence Livermore National Laboratory. The Plasma Diagnostics System (PDS) is responsible for control of MFTF-B plasma diagnostic instrumentation. An EtherNet Local Area Network links the workstations to a central multiprocessing system which furnishes data processing, data storage and control services for PDS. These workstations permit a physicist to command data acquisition, data processing, instrument control, and display of results. The interface is implemented as a metaphorical desktop, which helps the operator form a mental model of how the system works. As on a real desktop, functions are provided by sheets of paper (windows on a CRT screen) called worksheets. The worksheets may be invoked by pop-up menus and may be manipulated with a mouse. These worksheets are actually tasks that communicate with other tasks running in the central computer system. By making entries in the appropriate worksheet, a physicist may specify data acquisition or processing, control a diagnostic, or view a result

  2. An Australian Perspective On The Challenges For Computer And Network Security For Novice End-Users

    Directory of Open Access Journals (Sweden)

    Patryk Szewczyk

    2012-12-01

    Full Text Available It is common for end-users to have difficulty in using computer or network security appropriately and thus have often been ridiculed when misinterpreting instructions or procedures. This discussion paper details the outcomes of research undertaken over the past six years on why security is overly complex for end-users. The results indicate that multiple issues may render end-users vulnerable to security threats and that there is no single solution to address these problems. Studies on a small group of senior citizens has shown that educational seminars can be beneficial in ensuring that simple security aspects are understood and used appropriately.

  3. Continuity of care in the Health Care Network: negotiation between users and professionals

    Directory of Open Access Journals (Sweden)

    Maria Denise Schimith

    2014-12-01

    Full Text Available This study aimed to identify the negotiation and shared decision-making between professionals and users in a Family Health Unit and its influence on the continuity of care in the Health Care Network. Qualitative research created from a case study. One conducted 19 interviews, observation and document research. It was developed in a city in the countryside of Rio Grande do Sul, Brazil, in 2012. The results show that decisions used to happen unilaterally and that users and professionals looked for alternative ways to the continuity of care. It was not possible to identify the negotiation between professional and users and it was noticed that the user was alone looking for access. It is understood that primary care in the city researched needs to take responsibility for users and their access.

  4. Cooperative Detection for Primary User in Cognitive Radio Networks

    Directory of Open Access Journals (Sweden)

    Zhu Jia

    2009-01-01

    Full Text Available We propose two novel cooperative detection schemes based on the AF (Amplify and Forward and DF (Decode and Forward protocols to achieve spatial diversity gains for cognitive radio networks, which are referred to as the AF-CDS, (AF-based Cooperative Detection Scheme and DF-CDS (DF-based Cooperative Detection Scheme, respectively. Closed-form expressions of detection probabilities for the noncooperation scheme, AND-CDS (AND-based Cooperative Detection Scheme, AF-CDS and DF-CDS, are derived over Rayleigh fading channels. Also, we analyze the overall agility for the proposed cooperative detection schemes and show that our schemes can further reduce the detection time. In addition, we compare the DF-CDS with the AF-CDS in terms of detection probability and agility gain, depicting the advantage of DF-CDS at low SNR region and high false alarm probability region.

  5. Research on Network Defense Strategy Based on Honey Pot Technology

    Science.gov (United States)

    Hong, Jianchao; Hua, Ying

    2018-03-01

    As a new network security technology of active defense, The honeypot technology has become a very effective and practical method of decoy attackers. The thesis discusses the theory, structure, characteristic, design and implementation of Honeypot in detail. Aiming at the development of means of attack, put forward a kind of network defense technology based on honeypot technology, constructing a virtual Honeypot demonstrate the honeypot’s functions.

  6. Understanding and enhancing user acceptance of computer technology

    Science.gov (United States)

    Rouse, William B.; Morris, Nancy M.

    1986-01-01

    Technology-driven efforts to implement computer technology often encounter problems due to lack of acceptance or begrudging acceptance of the personnel involved. It is argued that individuals' acceptance of automation, in terms of either computerization or computer aiding, is heavily influenced by their perceptions of the impact of the automation on their discretion in performing their jobs. It is suggested that desired levels of discretion reflect needs to feel in control and achieve self-satisfaction in task performance, as well as perceptions of inadequacies of computer technology. Discussion of these factors leads to a structured set of considerations for performing front-end analysis, deciding what to automate, and implementing the resulting changes.

  7. Exploring the Relationship Between Online Social Network Site Usage and the Impact on Quality of Life for Older and Younger Users: An Interaction Analysis.

    Science.gov (United States)

    Quinn, Darren; Chen, Liming; Mulvenna, Maurice D; Bond, Raymond

    2016-09-29

    Analyzing content generated by users of social network sites has been shown to be beneficial across a number of disciplines. Such analysis has revealed the precise behavior of users that details their distinct patterns of engagement. An issue is evident whereby without direct engagement with end users, the reasoning for anomalies can only be the subject of conjecture. Furthermore, the impact of engaging in social network sites on quality of life is an area which has received little attention. Of particular interest is the impact of online social networking on older users, which is a demographic that is specifically vulnerable to social isolation. A review of the literature reveals a lack of knowledge concerning the impact of these technologies on such users and even less is known regarding how this impact varies across different demographics. The objective of our study was to analyze user interactions and to survey the attitudes of social network users directly, capturing data in four key areas: (1) functional usage, (2) behavioral patterns, (3) technology, and (4) quality of life. An online survey was constructed, comprising 32 questions. Each question directly related to a research question. Respondents were recruited through a variety of methods including email campaigns, Facebook advertisements, and promotion from related organizations. In total, data was collected from 919 users containing 446 younger and 473 older users. In comparison to younger users, a greater proportion of older users (289/473, 61.1% older vs 218/446, 48.9% younger) (PFacebook had either a positive or huge impact on their quality of life. Furthermore, a greater percentage of older users strongly agreed that Facebook strengthened their relationship with other people (64/473, 13.5% older vs 40/446, 9.0%younger) (P=.02). In comparison to younger users, a greater proportion of older users had more positive emotions-classified as slightly better or very good-during their engagement with

  8. User-led innovations and participation processes: lessons from sustainable energy technologies

    International Nuclear Information System (INIS)

    Ornetzeder, Michael; Rohracher, Harald

    2006-01-01

    In this paper we will pose the question whether a higher level of user participation could be used as a strategy to improve the development and dissemination of sustainable energy technologies. We will especially focus on user-led innovation processes with a high involvement of individual end-users. In our argument we will draw on several case studies in the field of renewable energy technologies-in particular solar collectors and biomass heating systems-and sustainable building technologies. Users in these case studies were involved in the design or planning processes, sometimes in a very selective way and with limited influence, sometimes very active and for quite a long period of time. Especially in the case of renewable energy technologies self-building groups were highly successful and resulted in improved and widely disseminated technologies. Based on the empirical results of our case studies we will critically discuss the potential of user involvement (especially in self-building groups) for the development and promotion of sustainable energy technologies and outline technological and social pre-conditions for the success of such approaches

  9. Design and value of service oriented technologies for smart business networking

    NARCIS (Netherlands)

    Alt, R.; Smits, M.T.; Beverungen, D.; Tuunanen, T.; Wijnhoven, F.

    2014-01-01

    Business networks that effectively use technologies and outperform competing networks are known as smart business networks. Theory hypothesizes that smart business networking requires a ‘Networked Business Operating System’ (NBOS), a technological architecture consisting of business logic, that

  10. Insecure Network, Unknown Connection: Understanding Wi-Fi Privacy Assumptions of Mobile Device Users

    Directory of Open Access Journals (Sweden)

    Bram Bonné

    2017-07-01

    Full Text Available Smartphones and other mobile devices have proliferated in the past five years. The expectation of mobile device users to always be online has led to Wi-Fi networks being offered by a variety of providers. Using these networks introduces multiple security risks. In this work, we assess to what extent the privacy stance of mobile device users corresponds with their actual behavior by conducting a study with 108 participants. Our methodology consists of monitoring Wi-Fi networks that the participants’ devices connect to and the connections made by apps on these devices, for a period of 30 days. Afterwards, participants are surveyed about their awareness and privacy sensitiveness. We show that while a higher expertise in computer networks corresponds to more awareness about the connections made by apps, neither this expertise nor the actual privacy stance of the participant translates to better security habits. Moreover, participants in general were unaware about a significant part of connections made by apps on their devices, a matter that is worsened by the fact that one third of Wi-Fi networks that participants connect to do not have any security enabled. Based on our results, we provide recommendations to network providers, developers and users on how to improve Wi-Fi security for mobile devices.

  11. Policy gaps and technological deficiencies in social networking environments: Implications for information sharing

    Directory of Open Access Journals (Sweden)

    Stephen M. Mutula

    2013-06-01

    Objectives: The study sought to investigate the following research objectives to: (1 describe the types of social networks, (2 examine global penetration of the social networks, (3 outline the users’ legitimate rights that must be protected in the social networking sites (SNS, (4 determine the methods employed by SNS to protect the users’ legitimate rights and (5 identify the policy gaps and technological deficiencies in the protection of the users’ legitimate rights in the SNS. Method: A literature survey and content analysis of the SNS user policies were used to address objective four and objective five respectively. Results: The most actively used sites were Facebook and Twitter. Asian markets were leading in participation and in creating content than any other region. Business, education, politics and governance sectors were actively using social networking sites. Social networking sites relied upon user trust and internet security features which however, were inefficient and inadequate. Conclusion: Whilst SNS were impacting people of varying ages and of various professional persuasions, there were increased concerns about the violation and infringement of the users’ legitimate rights. Reliance on user trust and technological security features SNS to protect the users’ legitimate rights seemed ineffectual and inadequate.

  12. Classifying and profiling Social Networking Site users: a latent segmentation approach.

    Science.gov (United States)

    Alarcón-del-Amo, María-del-Carmen; Lorenzo-Romero, Carlota; Gómez-Borja, Miguel-Ángel

    2011-09-01

    Social Networking Sites (SNSs) have showed an exponential growth in the last years. The first step for an efficient use of SNSs stems from an understanding of the individuals' behaviors within these sites. In this research, we have obtained a typology of SNS users through a latent segmentation approach, based on the frequency by which users perform different activities within the SNSs, sociodemographic variables, experience in SNSs, and dimensions related to their interaction patterns. Four different segments have been obtained. The "introvert" and "novel" users are the more occasional. They utilize SNSs mainly to communicate with friends, although "introverts" are more passive users. The "versatile" user performs different activities, although occasionally. Finally, the "expert-communicator" performs a greater variety of activities with a higher frequency. They tend to perform some marketing-related activities such as commenting on ads or gathering information about products and brands as well as commenting ads. The companies can take advantage of these segmentation schemes in different ways: first, by tracking and monitoring information interchange between users regarding their products and brands. Second, they should match the SNS users' profiles with their market targets to use SNSs as marketing tools. Finally, for most business, the expert users could be interesting opinion leaders and potential brand influencers.

  13. Multi-User Virtual Environments for Learning: Experience and Technology Design

    Science.gov (United States)

    Di Blas, N.; Bucciero, A.; Mainetti, L.; Paolini, P.

    2012-01-01

    Multi-User Virtual Environments (MUVEs) are often used to support learning in formal and informal educational contexts. A technology-based educational experience consists of several elements: content, syllabus, roles, sequence of activities, assignments, assessment procedures, etc. that must be aligned with the affordances of the technologies to…

  14. Technology Acceptance and User Experience: A Review of the Experiential Component in HCI

    DEFF Research Database (Denmark)

    Hornbæk, Kasper; Hertzum, Morten

    2017-01-01

    Understanding the mechanisms that shape the adoption and use of information technology is central to human-computer interaction. Two accounts are particularly vocal about these mechanisms, namely the technology acceptance model (TAM) and work on user experience (UX) models. In this study we revie...

  15. Mobile Computing and Ubiquitous Networking: Concepts, Technologies and Challenges.

    Science.gov (United States)

    Pierre, Samuel

    2001-01-01

    Analyzes concepts, technologies and challenges related to mobile computing and networking. Defines basic concepts of cellular systems. Describes the evolution of wireless technologies that constitute the foundations of mobile computing and ubiquitous networking. Presents characterization and issues of mobile computing. Analyzes economical and…

  16. Analysis and Comparison on Novel Sensor Network Security Access Technology

    Directory of Open Access Journals (Sweden)

    Ping LIU

    2014-01-01

    Full Text Available The article introduces against technical defects of traditional network access control system, detail NAC, NAP, UAC and TNC four kinds of new network security access technology, and this article analyzes and compares them. Security framework for wireless sensor networks SPINS defines the mechanism and algorithm of complete and effective in confidentiality, point-to-point message authentication, integrity, authentication, broadcast authentication.

  17. Wireless Fidelity (Wi-Fi) Broadband Network Technology: An ...

    African Journals Online (AJOL)

    Wireless Fidelity (Wi-Fi) broadband network technology has made tremendous impact in the growth of broadband wireless networks. There exists today several Wi-Fi access points that allow employees, partners and customers to access corporate data from almost anywhere and anytime. Wireless broadband networks are ...

  18. Interacting with Users in Social Networks: The Follow-back Problem

    Science.gov (United States)

    2016-05-02

    linked photos are videos, and the percentage that contain hashtags. We then used linear regression to predict that amount of time it took the users to...hyperlinked environment. J. ACM, 46:604 – 632, 1999. [27] H. Kwak, C. Lee, H. Park, and S. Moon . What is Twitter, a social network or a news media? In

  19. The Relationship Between Attachment Styles, Self-Monitoring and Cybercrime in Social Network Users

    OpenAIRE

    Yaghoobi, Abolghasem; Mohammadzade, Serwa; Chegini, Ali Asghar; Yarmohammadi Vasel, Mosaeib; Zoghi Paidar, Mohammad Reza

    2016-01-01

    Background The anonymity in the cyberspace environment, as well as the rapid advent of and improvements to online activities has increased cybercrime. Objectives The aim of this paper was to survey the relationship between attachment styles, self-monitoring and cybercrime in social network users. Patients and Methods The Collins and Read Adult Attachment Scale, and the Snyder self-...

  20. Social Networking Website Users and Privacy Concerns: A Mixed Methods Investigation

    Science.gov (United States)

    2009-03-01

    Facebook from girls getting messages on Facebook of girls doing ridiculous poses and almost naked saying, ‘Hello, I see that you work in Loreal. I just...Analysis .......................................................................................................19 le 12 . Table of Contents...ten social networking websites experienced 47 percent growth compared to the previous year and attracted 45 percent of all Internet users (Nielsen

  1. Discovering the influential users oriented to viral marketing based on online social networks

    Science.gov (United States)

    Zhu, Zhiguo

    2013-08-01

    The target of viral marketing on the platform of popular online social networks is to rapidly propagate marketing information at lower cost and increase sales, in which a key problem is how to precisely discover the most influential users in the process of information diffusion. A novel method is proposed in this paper for helping companies to identify such users as seeds to maximize information diffusion in the viral marketing. Firstly, the user trust network oriented to viral marketing and users’ combined interest degree in the network including isolated users are extensively defined. Next, we construct a model considering the time factor to simulate the process of information diffusion in viral marketing and propose a dynamic algorithm description. Finally, experiments are conducted with a real dataset extracted from the famous SNS website Epinions. The experimental results indicate that the proposed algorithm has better scalability and is less time-consuming. Compared with the classical model, the proposed algorithm achieved a better performance than does the classical method on the two aspects of network coverage rate and time-consumption in our four sub-datasets.

  2. Featuring Multiple Local Optima to Assist the User in the Interpretation of Induced Bayesian Network Models

    DEFF Research Database (Denmark)

    Dalgaard, Jens; Pena, Jose; Kocka, Tomas

    2004-01-01

    We propose a method to assist the user in the interpretation of the best Bayesian network model indu- ced from data. The method consists in extracting relevant features from the model (e.g. edges, directed paths and Markov blankets) and, then, assessing the con¯dence in them by studying multiple...

  3. FaceMashup: An End-User Development Tool for Social Network Data

    Directory of Open Access Journals (Sweden)

    Daniele Massa

    2016-03-01

    Full Text Available Every day, each active social network user produces and shares texts, images and videos. While developers can access such data through application programming interfaces (APIs for creating games, visualizations and routines, end users have less control on such information. Their access is mediated by the social application features, which limits them in combining sources, filtering results and performing actions on groups of elements. In order to fill this gap, we introduce FaceMashup, an end user development (EUD environment supporting the manipulation of the Facebook graph. We describe the tool interface, documenting the choices we made during the design iterations. Data types are represented through widgets containing user interface (UI elements similar to those used in the social network application. Widgets can be connected with each other with the drag and drop of their inner fields, and the application updates their content. Finally, we report the results of a user-test on the FaceMashup prototype, which shows a good acceptance of the environment by end-users.

  4. User Matching with Relation to the Stable Marriage Problem in Cognitive Radio Networks

    KAUST Repository

    Hamza, Doha R.

    2017-03-20

    We consider a network comprised of multiple primary users (PUs) and multiple secondary users (SUs), where the SUs seek access to a set of orthogonal channels each occupied by one PU. Only one SU is allowed to coexist with a given PU. We propose a distributed matching algorithm to pair the network users, where a Stackelberg game model is assumed for the interaction between the paired PU and SU. The selected secondary is given access in exchange for monetary compensation to the primary. The PU optimizes the interference price it charges to a given SU and the power allocation to maintain communication. The SU optimizes its power demand so as to maximize its utility. Our algorithm provides a unique stable matching. Numerical results indicate the advantage of the proposed algorithm over other reference schemes.

  5. Image Restoration Technology Based on Discrete Neural network

    Directory of Open Access Journals (Sweden)

    Zhou Duoying

    2015-01-01

    Full Text Available With the development of computer science and technology, the development of artificial intelligence advances rapidly in the field of image restoration. Based on the MATLAB platform, this paper constructs a kind of image restoration technology of artificial intelligence based on the discrete neural network and feedforward network, and carries out simulation and contrast of the restoration process by the use of the bionic algorithm. Through the application of simulation restoration technology, this paper verifies that the discrete neural network has a good convergence and identification capability in the image restoration technology with a better effect than that of the feedforward network. The restoration technology based on the discrete neural network can provide a reliable mathematical model for this field.

  6. Computer-related assistive technology: satisfaction and experiences among users with disabilities.

    Science.gov (United States)

    Burton, Mary; Nieuwenhuijsen, Els R; Epstein, Marcy J

    2008-01-01

    Many people with disabilities use assistive technology devices (ATDs) for computer access. The specific focus of this exploratory study was (a) to assess the experiences, opinions, and satisfaction levels of 24 individuals with disabilities using computer-related ATDs; (b) to investigate their awareness of health risk factors related to computer usage; and (c) to examine the psychosocial impact of computer-related ATDs on users. Data were collected via telephone interviews with 24 individuals with physical disabilities who had experience using one or more ATDs. The Quebec User Evaluation with Assistive Technology instrument was used to evaluate users' satisfaction with ATDs in a number of dimensions, including their physical attributes. The Psychosocial Impact of Assistive Devices Scale measured the psychosocial impact (i.e., independence, competence, and adequacy) of an ATD on users. Additional questions were posed to gather information about user's opinions and experiences. Training appeared to be an important component for ATD users, many of whom preferred a setting to try out devices rather than group or individual training. Respondents with visual impairments revealed a higher level of adaptability versus those without visual impairments (p = .001). Additional research is needed to develop specific survey items focused on users of computer-related ATDs and the evaluation of the psychosocial impact of ATDs on computer users.

  7. Enabling mobile/wireless broadband technologies and services for the next billion users

    CSIR Research Space (South Africa)

    Mekuria, F

    2011-09-01

    Full Text Available -HSPA technologies, are the most common wireless broadband technology and facilitates a standards-based migration which allows the utilization of legacy infrastructure. 3G-HSPA systems can interoperate and share the core network with the legacy GSM 2G and 2.5G... networks. Also a packet switching core-network can be designed to share and interoperate with WiFi and WiMAX broadband wireless technologies. It is clear that standards-based migration lowers the cost of mobile broadband services. By utilizing...

  8. QNAP 1263U Network Attached Storage (NAS)/ Storage Area Network (SAN) Device Users Guide

    Science.gov (United States)

    2016-11-01

    ARL-TN-0804 ● NOV 2016 US Army Research Laboratory QNAP 1263U Network Attached Storage ( NAS )/ Storage Area Network ( SAN ) Device...2016 US Army Research Laboratory QNAP 1263U Network Attached Storage ( NAS )/ Storage Area Network ( SAN ) Device User’s Guide by Benjamin...locking, the NAS will transfer data at a file level. A SAN uses the iSCSI transfer protocol to open the disks to the computer as local hard drives. As

  9. [Social network analysis and high risk behavior characteristics of recreational drug users: a qualitative study].

    Science.gov (United States)

    Wu, Di; Wang, Zhenhong; Jiang, Zhenxia; Fu, Xiaojing; Li, Hui; Zhang, Dapeng; Liu, Hui; Hu, Yifei

    2014-11-01

    To understand the characteristics of recreational drug users' behaviors and social network, as well as their potential impact to the transmission of sexual transmitted infections (STI). Qualitative interview was used to collect information on rough estimation of population size and behavior change before and after recreational drug use. A total of 120 participants were recruited by convenient sampling from April to October, 2013 in a community of Qingdao city. Blood specimens were taken for HIV/syphilis serological testing and social network analysis was performed to understand the characteristics of their behavior and social network. All participants used methamphetamine and 103 of them showed social connection. The prevalence of syphilis and HIV were 24.2% (29/120) and 2.5% (3/120) respectively. The estimated size of recreational drug users was big with a wide diversity of occupations and age range, and males were more frequent than females. Drug use may affect condom use and frequent drug users showed symptom of psychosis and neuro-toxicities. The size of social network was 2.45 ± 1.63 in the past 6 months, which indicated an increasing trend of the sexual partner number and risky behaviors. Recreational drug use could increase the size of social network among sex partners, the frequency of risky sexual behaviors and syphilis prevalence, which indicate a high risk of HIV/STI among this population as well as a huge burden of disease prevention and control in the future.

  10. Navigating the massive world of reddit: using backbone networks to map user interests in social media

    Directory of Open Access Journals (Sweden)

    Randal S. Olson

    2015-05-01

    Full Text Available In the massive online worlds of social media, users frequently rely on organizing themselves around specific topics of interest to find and engage with like-minded people. However, navigating these massive worlds and finding topics of specific interest often proves difficult because the worlds are mostly organized haphazardly, leaving users to find relevant interests by word of mouth or using a basic search feature. Here, we report on a method using the backbone of a network to create a map of the primary topics of interest in any social network. To demonstrate the method, we build an interest map for the social news web site reddit and show how such a map could be used to navigate a social media world. Moreover, we analyze the network properties of the reddit social network and find that it has a scale-free, small-world, and modular community structure, much like other online social networks such as Facebook and Twitter. We suggest that the integration of interest maps into popular social media platforms will assist users in organizing themselves into more specific interest groups, which will help alleviate the overcrowding effect often observed in large online communities.

  11. Strong authentication of remote users over insecure networks by using fingerprint-biometric and smart cards

    Science.gov (United States)

    Khan, Muhammad K.; Zhang, Jiashu

    2006-04-01

    Recently, Lee et al. and Lin-Lai proposed fingerprint-based remote user authentication schemes using smart cards. We demonstrate that their schemes are vulnerable and susceptible to the attack and have practical pitfalls. Their schemes perform only unilateral authentication (only client authentication) and there is no mutual authentication between user and remote system, so their schemes suscept from the server spoofing attack. To overcome the flaw, we present a strong remote user authentication scheme by using fingerprint-biometric and smart cards. The proposed scheme is an extended and generalized form of ElGamal's signature scheme whose security is based on discrete logarithm problem, which is not yet forged. Proposed scheme not only overcome drawbacks and problems of previous schemes, but also provide a strong authentication of remote users over insecure network. In addition, computational costs and efficiency of the proposed scheme are better than other related schemes.

  12. A Neural Network Approach to Intention Modeling for User-Adapted Conversational Agents.

    Science.gov (United States)

    Griol, David; Callejas, Zoraida

    2016-01-01

    Spoken dialogue systems have been proposed to enable a more natural and intuitive interaction with the environment and human-computer interfaces. In this contribution, we present a framework based on neural networks that allows modeling of the user's intention during the dialogue and uses this prediction to dynamically adapt the dialogue model of the system taking into consideration the user's needs and preferences. We have evaluated our proposal to develop a user-adapted spoken dialogue system that facilitates tourist information and services and provide a detailed discussion of the positive influence of our proposal in the success of the interaction, the information and services provided, and the quality perceived by the users.

  13. Social Networks as Enablers of Enterprise Creativity: Evidence from Portuguese Firms and Users

    Directory of Open Access Journals (Sweden)

    Silvia Fernandes

    2016-06-01

    Full Text Available The present work analyzes the profiles of social networks’ users, individuals and enterprises in Algarve (Portugal, having accomplished online questionnaires. Samples of 230 users and 70 firms were collected. According to data obtained there are different behaviors. Users’ results highlight the need of harnessing the potential of recruitment and business projects through social networks, as searching for knowledge, communication and professional relations are expressive. Firms’ results reveal two types of social networks’ use: 1 knowledge search, interact with customers, launch new products; and 2 potential for marketing. Users’ desire of expressing own ideas and being creative had low importance. In social networks they auscultate more about what others are doing than revealing own aspirations. Here firms can act in order to shape users’ attitudes and preferences to their creativity. Thus, enterprises can use the first level of social networks (knowledge and product-customer interaction in order to enhance the second level (marketing and innovation.

  14. Organizational Application of Social Networking Information Technologies

    Science.gov (United States)

    Reppert, Jeffrey R.

    2012-01-01

    The focus of this qualitative research study using the Delphi method is to provide a framework for leaders to develop their own social networks. By exploring concerns in four areas, leaders may be able to better plan, implement, and manage social networking systems in organizations. The areas addressed are: (a) social networking using…

  15. Survey of Promising Technologies for 5G Networks

    Directory of Open Access Journals (Sweden)

    Nam Tuan Le

    2016-01-01

    Full Text Available As an enhancement of cellular networks, the future-generation 5G network can be considered an ultra-high-speed technology. The proposed 5G network might include all types of advanced dominant technologies to provide remarkable services. Consequently, new architectures and service management schemes for different applications of the emerging technologies need to be recommended to solve issues related to data traffic capacity, high data rate, and reliability for ensuring QoS. Cloud computing, Internet of things (IoT, and software-defined networking (SDN have become some of the core technologies for the 5G network. Cloud-based services provide flexible and efficient solutions for information and communications technology by reducing the cost of investing in and managing information technology infrastructure. In terms of functionality, SDN is a promising architecture that decouples control planes and data planes to support programmability, adaptability, and flexibility in ever-changing network architectures. However, IoT combines cloud computing and SDN to achieve greater productivity for evolving technologies in 5G by facilitating interaction between the physical and human world. The major objective of this study provides a lawless vision on comprehensive works related to enabling technologies for the next generation of mobile systems and networks, mainly focusing on 5G mobile communications.

  16. Design and simulation of sensor networks for tracking Wifi users in outdoor urban environments

    Science.gov (United States)

    Thron, Christopher; Tran, Khoi; Smith, Douglas; Benincasa, Daniel

    2017-05-01

    We present a proof-of-concept investigation into the use of sensor networks for tracking of WiFi users in outdoor urban environments. Sensors are fixed, and are capable of measuring signal power from users' WiFi devices. We derive a maximum likelihood estimate for user location based on instantaneous sensor power measurements. The algorithm takes into account the effects of power control, and is self-calibrating in that the signal power model used by the location algorithm is adjusted and improved as part of the operation of the network. Simulation results to verify the system's performance are presented. The simulation scenario is based on a 1.5 km2 area of lower Manhattan, The self-calibration mechanism was verified for initial rms (root mean square) errors of up to 12 dB in the channel power estimates: rms errors were reduced by over 60% in 300 track-hours, in systems with limited power control. Under typical operating conditions with (without) power control, location rms errors are about 8.5 (5) meters with 90% accuracy within 9 (13) meters, for both pedestrian and vehicular users. The distance error distributions for smaller distances (<30 m) are well-approximated by an exponential distribution, while the distributions for large distance errors have fat tails. The issue of optimal sensor placement in the sensor network is also addressed. We specify a linear programming algorithm for determining sensor placement for networks with reduced number of sensors. In our test case, the algorithm produces a network with 18.5% fewer sensors with comparable accuracy estimation performance. Finally, we discuss future research directions for improving the accuracy and capabilities of sensor network systems in urban environments.

  17. Image Restoration Technology Based on Discrete Neural network

    OpenAIRE

    Zhou Duoying

    2015-01-01

    With the development of computer science and technology, the development of artificial intelligence advances rapidly in the field of image restoration. Based on the MATLAB platform, this paper constructs a kind of image restoration technology of artificial intelligence based on the discrete neural network and feedforward network, and carries out simulation and contrast of the restoration process by the use of the bionic algorithm. Through the application of simulation restoration technology, ...

  18. Application of wireless sensor network technology in logistics information system

    Science.gov (United States)

    Xu, Tao; Gong, Lina; Zhang, Wei; Li, Xuhong; Wang, Xia; Pan, Wenwen

    2017-04-01

    This paper introduces the basic concepts of active RFID (WSN-ARFID) based on wireless sensor networks and analyzes the shortcomings of the existing RFID-based logistics monitoring system. Integrated wireless sensor network technology and the scrambling point of RFID technology. A new real-time logistics detection system based on WSN and RFID, a model of logistics system based on WSN-ARFID is proposed, and the feasibility of this technology applied to logistics field is analyzed.

  19. Soft technologies as generating satisfaction in users of a Family Health Unit

    Directory of Open Access Journals (Sweden)

    Sonia Mara Neves Ferri

    2007-01-01

    Full Text Available This study had the purpose to evaluate the quality of the health service provided at a Family Health Unit (FHU, with emphasis on user satisfaction, based on soft technologies. Furthermore, this study also aimed to analyze the aspects of health care that generated user satisfaction or dissatisfaction regarding attachment, accountability, providing solutions, expectations, relationship, comfort, and access, and to identify recommendations for local interventions. The authors made a general characterization of the population seen at the studied service, and then selected the subjects. The study used a qualitative approach. Data were collected in semi-structured interviews, and ordered using the Collective Subject Discourse (CSD method. The analysis reveals the importance that service users assign to the soft technologies, but also shows the need to reduce the waiting time for medical consultations and referrals, and to obtain access to medication and dental care at the same location. These factors generated great dissatisfaction among users.

  20. Opinion Mining for User Generated Design By Social Networking Service and Japanese Manga

    Directory of Open Access Journals (Sweden)

    Anak Agung Gede Dharma

    2011-12-01

    Full Text Available The growth of Social Networking Service (SNS has created a new potential in marketing. While users communicate and interact via SNS, the list of their conversation, which is called casual data can be used to determine their needs or aspirations. SNS can be very useful for product/service developers, especially when developing new ideas or simply evaluating the feasibility of their existing products/services. Furthermore, SNS provides a unique system that enables expressive and two-way communication between its users. SNS is known for its effectiveness in delivering fresh news and information, thus it can be used as promotional media. Although several online services that utilize SNS and casual data have been provided, the purpose of those services is still unclear and ineffective. In those services, users were only asked for their opinions without receiving sufficient feedbacks. Therefore, to solve these problems we propose an innovative way of utilizing SNS and casual data in designing user generated design. In our proposed system, users can directly contribute to the product/service development process in an interesting way. We designed an online service, which allows users to posts manga that describes their original idea. While contributing to the product/service development, they can also benefit from expressing their hobbies and receiving feedbacks from other users.

  1. Delay Tolerant Networking with Data Triage Method based on Emergent User Policies for Disaster Information Network System

    Directory of Open Access Journals (Sweden)

    Noriki Uchida

    2014-01-01

    Full Text Available When Disaster Information Network System is considered in local areas that were heavy damaged by the East Japan Great Earthquake in 2011, the resiliency of the network system is one of significant subjects for the restoration of the areas. DTN (Delay Tolerant Network has been focused for the effective methods for such inoperable network circumstances. However, when DTN is applied for the local areas, there are some problems such as message delivery rate and latency because there are fewer roads, cars, and pedestrians than in urban areas. In this paper, we propose the Enhanced Media Coordinate System for its architecture, and Data Triage method by emergent user policies is introduced to improve the QoS in Disaster Information Network System in local areas. In the proposed method, every message is tagged with the priority levels by data types with considering emergent user policies, and the high priority messages are firstly duplicated to transmittable nodes. Then, the experimental results by the GIS map of a Japanese coastal town and the future studies are discussed.

  2. Integrated IoT technology in industrial lasers for the improved user experience

    Science.gov (United States)

    Ding, Jianwu; Liu, Jinhui

    2018-02-01

    The end users' biggest concern for any industrial equipment is the reliability and the service down-time. This is especially true for industrial lasers as they are typically used in fully or semi- automated processes. Here we demonstrate how to use the integrated Internet of Things (IoT) technology in industrial lasers to address the reliability and the service down-time so to improve end users' experience.

  3. Distracted: Academic Performance Differences between Teen Users and Non-Users of MySpace and other Communication Technology

    Directory of Open Access Journals (Sweden)

    Tamyra A. Pierce

    2008-06-01

    Full Text Available This study examined the differences in academic performance between teen users and non-users of various communication technologies. Participants included 517 high school students who completed a self-report survey. The results revealed that approximately 3/4 of the teens had a MySpace account and a cell phone and more than 1/2 had an IM account. Results also showed that those who had a MySpace account, cell phone and IM had signifi cantly lower grades than those who did not. Results also revealed that teens who used their MySpace, cell phone and IM while doing their homework reported having lower grades than those who did not use the technology while doing their homework. In addition, those who put off doing their homework to spend time on MySpace also reported lower grades than those who did not put off doing their homework to spend time with MySpace. Finally, results showed that 28% text messaged during class from always to frequently, and 5% reported text messaging during an exam from always to frequently.

  4. Full-diversity partial interference cancellation for multi-user wireless relaying networks

    KAUST Repository

    El Astal, M. T O

    2013-12-01

    We focus on the uplink channel of multi-user wireless relaying networks in a coverage extension scenario. The network consists of two users, a single half duplex (HD) relay and a destination, all equipped with multiple antennas. Perfect channel state information (CSI) is assumed to be available exclusively at the receiving nodes (i.e., the relay and the destination) while the users are assumed to be completely blind. The communication through the considered network takes place over two phases. During the first phase, both users send their information concurrently to the relay. The second phase consists of decoding the received data and forwarding it simultaneously to the destination. A transmission scheme that achieves full-diversity under partial interference cancellation (PIC) group decoding is proposed. Unlike many existing schemes, it allows the concurrent transmission in both phases while achieving the full-diversity gain of full time division multiple access (TDMA) transmission regardless of the number of antennas at each node. Numerical comparison with existing schemes in the literature is provided to corroborate our theoretical claims. It is found that our interference cancellation (IC) scheme clearly outperforms existing schemes at the expense of an affordable increase in decoding complexity at both of the relay and destination. © 2013 IEEE.

  5. User acceptance factors of hospital information systems and related technologies: Systematic review.

    Science.gov (United States)

    Handayani, Putu Wuri; Hidayanto, Achmad Nizar; Budi, Indra

    2017-08-22

    This study reviews the literature on the most important acceptance factors associated with Hospital Information Systems (HIS) and related technologies based on user groups' perspectives (medical staff, hospital management, administrative personnel, patient, medical student, and IT staff), which can assist researchers and hospital management to develop suitable acceptance models to improve the quality of HIS. We conducted searches in online databases with large repositories of academic studies, written in English and fully accessible by the authors. The articles being reviewed are related to health information technology (HIT), clinical information systems (CIS), HIS, electronic medical records (EMR), telemedicine or telehealth, picture archiving and communication systems (PACS), radio frequency identification (RFID), and computerized physician order entry (CPOE), where the use of most of those applications and technologies is highly integrated. A predefined string was used to extract 1,005 articles, and the results were reviewed and checked. The results of this study found 15 user acceptance factors related to HIS and related technologies that were frequently identified by a minimum of five previous studies. These factors were related to individual, technological, and organizational factors. In addition, HIS and related technologies' user acceptance factors in each user group describe different results.

  6. Challenges of user-centred assistive technology provision in Australia: shopping without a prescription.

    Science.gov (United States)

    Steel, Emily J; Layton, Natasha Ann; Foster, Michele M; Bennett, Sally

    2016-01-01

    People with disability have a right to assistive technology devices and services, to support their inclusion and participation in society. User-centred approaches aim to address consumer dissatisfaction and sub-optimal outcomes from assistive technology (AT) provision, but make assumptions of consumer literacy and empowerment. Policy discourses about consumer choice prompt careful reflection, and this paper aims to provide a critical perspective on user involvement in assistive technology provision. User-centred approaches are considered, using literature to critically reflect on what user involvement means in AT provision. Challenges at the level of interactions between practitioners and consumers, and also the level of markets and policies are discussed, using examples from Australia. There is no unanimous conceptual framework for user-centred practice. Power imbalances and differing perspectives between practitioners and consumers make it difficult for consumers to feel empowered. Online access to information and international suppliers has not surmounted information asymmetries for consumers or lifted the regulation of publicly funded AT devices. Ensuring access and equity in the public provision of AT is challenging in an expanding market with diverse stakeholders. Consumers require personalised information and support to facilitate their involvement and choice in AT provision. Implications for Rehabilitation Variations in approaches informing AT provision practices have a profound impact on equity of access and outcomes for consumers. An internationalised and online market for AT devices is increasing the need for effective information provision strategies and services. Power imbalances between practitioners and consumers present barriers to the realisation of user-centred practice.

  7. CP-ABE Based Privacy-Preserving User Profile Matching in Mobile Social Networks.

    Directory of Open Access Journals (Sweden)

    Weirong Cui

    Full Text Available Privacy-preserving profile matching, a challenging task in mobile social networks, is getting more attention in recent years. In this paper, we propose a novel scheme that is based on ciphertext-policy attribute-based encryption to tackle this problem. In our scheme, a user can submit a preference-profile and search for users with matching-profile in decentralized mobile social networks. In this process, no participant's profile and the submitted preference-profile is exposed. Meanwhile, a secure communication channel can be established between the pair of successfully matched users. In contrast to existing related schemes which are mainly based on the secure multi-party computation, our scheme can provide verifiability (both the initiator and any unmatched user cannot cheat each other to pretend to be matched, and requires few interactions among users. We provide thorough security analysis and performance evaluation on our scheme, and show its advantages in terms of security, efficiency and usability over state-of-the-art schemes.

  8. Robust Nash Dynamic Game Strategy for User Cooperation Energy Efficiency in Wireless Cellular Networks

    Directory of Open Access Journals (Sweden)

    Shuhuan Wen

    2012-01-01

    Full Text Available Recently, there is an emerging trend of addressing “energy efficiency” aspect of wireless communications. It has been shown that cooperating users relay each other's information to improve data rates. The energy is limited in the wireless cellular network, but the mobile users refuse to relay. This paper presents an approach that encourages user cooperation in order to improve the energy efficiency. The game theory is an efficient method to solve such conflicts. We present a cellular framework in which two mobile users, who desire to communicate with a common base station, may cooperate via decode-and-forward relaying. In the case of imperfect information assumption, cooperative Nash dynamic game is used between the two users' cooperation to tackle the decision making problems: whether to cooperate and how to cooperate in wireless networks. The scheme based on “cooperative game theory” can achieve general pareto-optimal performance for cooperative games, and thus, maximize the entire system payoff while maintaining fairness.

  9. User survey at Waterford Institute of Technology Libraries: How a traditional approach to surveys can inform library service delivery

    OpenAIRE

    Hayden, Helen; O'Brien, Terry; Ó Rathaille, Maoilíosa

    2005-01-01

    This paper describes a comprehensive user survey carried out in an Irish higher education academic library (Waterford Institute of Technology library service) as part of a strategic initiative to engage with library users.

  10. Simulation analysis of security performance of DPSKOCDMA network via virtual user scheme

    Directory of Open Access Journals (Sweden)

    Vishav Jyoti

    2012-07-01

    Full Text Available A novel technique to enhance the security of an optical code division multipleaccess (OCDMA system against eavesdropping is proposed. It has been observed that whena single user is active in the network, an eavesdropper can easily sift the data beingtransmitted without decoding. To increase the security, a virtual user scheme is proposed andsimulated on a differential phase shift keying (DPSK OCDMA system. By using the virtualuser scheme, the security of the DPSK-OCDMA system can be effectively improved and themultiple access interference, which is generally considered to be a limitation of the OCDMAsystem, is used to increase the confidentiality of the system.

  11. Methods and tools in user-centred design for information technology

    CERN Document Server

    Galer, Margaret; Ziegler, J; Galer, Mark

    1992-01-01

    This book is concerned with the development of human factorsinputs to software design. The aim is to create products whichmatch the requirements and characteristics of users and whichoffer usable user interfaces. The HUFIT project - Human Factorsin Information Technology - was carried out within the EuropeanStrategic Programme for Research and Development in InformationTechnology (ESPRIT) with the objective of enhancing the qualityof software design within the European Community. The variety ofactivities undertaken to achieve this goal are reflected in thisbook. It describes human factors know

  12. A Novel Frequency Communication Technology in Power Distribution Communication Network

    Directory of Open Access Journals (Sweden)

    Li Ying-Jun

    2017-01-01

    Full Text Available With the expansion of the power terminal access network scale, the main road corridor resources, branch line cable Laying difficulties has become an important factor restricting the construction of the network. In this paper, we focus on the frequency communication technology in power distribution communication network, and design a novel technology in communication mode, error correcting coding and data transfer frame format. We also discuss the influence of voltage phase difference on power frequency communication. Meanwhile, we present the application scenario Electricity information collection, electricity remote control and other power business in smart grid with the novel frequency communication technology.

  13. A simplistic model for identifying prominent web users in directed multiplex social networks: a case study using Twitter networks

    Science.gov (United States)

    Loucif, Hemza; Boubetra, Abdelhak; Akrouf, Samir

    2016-10-01

    This paper aims to describe a new simplistic model dedicated to gauge the online influence of Twitter users based on a mixture of structural and interactional features. The model is an additive mathematical formulation which involves two main parts. The first part serves to measure the influence of the Twitter user on just his neighbourhood covering his followers. However, the second part evaluates the potential influence of the Twitter user beyond the circle of his followers. Particularly, it measures the likelihood that the tweets of the Twitter user will spread further within the social graph through the retweeting process. The model is tested on a data set involving four kinds of real-world egocentric networks. The empirical results reveal that an active ordinary user is more prominent than a non-active celebrity one. A simple comparison is conducted between the proposed model and two existing simplistic approaches. The results show that our model generates the most realistic influence scores due to its dealing with both explicit (structural and interactional) and implicit features.

  14. Empowering communities : A method for the legitimate user-driven specification of network information systems

    NARCIS (Netherlands)

    de Moor, A.

    1999-01-01

    Collaborative work is increasingly being mediated by distributed information technologies such as the Internet. However, it is difficult to make the virtual professional communities, in which this collaboration takes place, operate successfully. One of the reasons is that users are not sufficiently

  15. User-Centered Authentication: LDAP, WRAP, X.509, XML (SIG LAN: Library Automation and Networks).

    Science.gov (United States)

    Coble, Jim

    2000-01-01

    Presents an abstract for a planned panel session on technologies for user-centered authentication and authorization currently deployed in pilot or production implementations in academic computing. Presentations included: "Implementing LSAP for Single-Password Access to Campus Resources" (Layne Nordgren); "Implementing a Scalable…

  16. A versatile model for TCP bandwidth sharing in networks with heterogeneous users

    NARCIS (Netherlands)

    Abendroth, D.; Berg, J.L. van den; Mandjes, M.

    2006-01-01

    Enabled by the emergence of various access technologies (such as ADSL and wireless LAN), the number of users with high-speed access to the Internet is growing rapidly, and their expectation with respect to the quality-of-service of the applications has been increasing accordingly. With TCP being the

  17. Security Enhanced User Authentication Protocol for Wireless Sensor Networks Using Elliptic Curves Cryptography

    Science.gov (United States)

    Choi, Younsung; Lee, Donghoon; Kim, Jiye; Jung, Jaewook; Nam, Junghyun; Won, Dongho

    2014-01-01

    Wireless sensor networks (WSNs) consist of sensors, gateways and users. Sensors are widely distributed to monitor various conditions, such as temperature, sound, speed and pressure but they have limited computational ability and energy. To reduce the resource use of sensors and enhance the security of WSNs, various user authentication protocols have been proposed. In 2011, Yeh et al. first proposed a user authentication protocol based on elliptic curve cryptography (ECC) for WSNs. However, it turned out that Yeh et al.'s protocol does not provide mutual authentication, perfect forward secrecy, and key agreement between the user and sensor. Later in 2013, Shi et al. proposed a new user authentication protocol that improves both security and efficiency of Yeh et al.'s protocol. However, Shi et al.'s improvement introduces other security weaknesses. In this paper, we show that Shi et al.'s improved protocol is vulnerable to session key attack, stolen smart card attack, and sensor energy exhausting attack. In addition, we propose a new, security-enhanced user authentication protocol using ECC for WSNs. PMID:24919012

  18. Security Enhanced User Authentication Protocol for Wireless Sensor Networks Using Elliptic Curves Cryptography

    Directory of Open Access Journals (Sweden)

    Younsung Choi

    2014-06-01

    Full Text Available Wireless sensor networks (WSNs consist of sensors, gateways and users. Sensors are widely distributed to monitor various conditions, such as temperature, sound, speed and pressure but they have limited computational ability and energy. To reduce the resource use of sensors and enhance the security of WSNs, various user authentication protocols have been proposed. In 2011, Yeh et al. first proposed a user authentication protocol based on elliptic curve cryptography (ECC for WSNs. However, it turned out that Yeh et al.’s protocol does not provide mutual authentication, perfect forward secrecy, and key agreement between the user and sensor. Later in 2013, Shi et al. proposed a new user authentication protocol that improves both security and efficiency of Yeh et al.’s protocol. However, Shi et al.’s improvement introduces other security weaknesses. In this paper, we show that Shi et al.’s improved protocol is vulnerable to session key attack, stolen smart card attack, and sensor energy exhausting attack. In addition, we propose a new, security-enhanced user authentication protocol using ECC for WSNs.

  19. Security of social network credentials for accessing course portal: Users' experience

    Science.gov (United States)

    Katuk, Norliza; Fong, Choo Sok; Chun, Koo Lee

    2015-12-01

    Social login (SL) has recently emerged as a solution for single sign-on (SSO) within the web and mobile environments. It allows users to use their existing social network credentials (SNC) to login to third party web applications without the need to create a new identity in the intended applications' database. Although it has been used by many web application providers, its' applicability in accessing learning materials is not yet fully investigated. Hence, this research aims to explore users' (i.e., instructors' and students') perception and experience on the security of SL for accessing learning contents. A course portal was developed for students at a higher learning institution and it provides two types of user authentications (i) traditional user authentication, and (ii) SL facility. Users comprised instructors and students evaluated the login facility of the course portal through a controlled lab experimental study following the within-subject design. The participants provided their feedback in terms of the security of SL for accessing learning contents. The study revealed that users preferred to use SL over the traditional authentication, however, they concerned on the security of SL and their privacy.

  20. A novel and efficient user access control scheme for wireless body area sensor networks

    Directory of Open Access Journals (Sweden)

    Santanu Chatterjee

    2014-07-01

    Full Text Available Wireless body area networks (WBANs can be applied to provide healthcare and patient monitoring. However, patient privacy can be vulnerable in a WBAN unless security is considered. Access to authorized users for the correct information and resources for different services can be provided with the help of efficient user access control mechanisms. This paper proposes a new user access control scheme for a WBAN. The proposed scheme makes use of a group-based user access ID, an access privilege mask, and a password. An elliptic curve cryptography-based public key cryptosystem is used to ensure that a particular legitimate user can only access the information for which he/she is authorized. We show that our scheme performs better than previously existing user access control schemes. Through a security analysis, we show that our scheme is secure against possible known attacks. Furthermore, through a formal security verification using the AVISPA (Automated Validation of Internet Security Protocols and Applications tool, we show that our scheme is also secure against passive and active attacks.

  1. Security enhanced user authentication protocol for wireless sensor networks using elliptic curves cryptography.

    Science.gov (United States)

    Choi, Younsung; Lee, Donghoon; Kim, Jiye; Jung, Jaewook; Nam, Junghyun; Won, Dongho

    2014-06-10

    Wireless sensor networks (WSNs) consist of sensors, gateways and users. Sensors are widely distributed to monitor various conditions, such as temperature, sound, speed and pressure but they have limited computational ability and energy. To reduce the resource use of sensors and enhance the security of WSNs, various user authentication protocols have been proposed. In 2011, Yeh et al. first proposed a user authentication protocol based on elliptic curve cryptography (ECC) for WSNs. However, it turned out that Yeh et al.'s protocol does not provide mutual authentication, perfect forward secrecy, and key agreement between the user and sensor. Later in 2013, Shi et al. proposed a new user authentication protocol that improves both security and efficiency of Yeh et al.'s protocol. However, Shi et al.'s improvement introduces other security weaknesses. In this paper, we show that Shi et al.'s improved protocol is vulnerable to session key attack, stolen smart card attack, and sensor energy exhausting attack. In addition, we propose a new, security-enhanced user authentication protocol using ECC for WSNs.

  2. Research on key technology of space laser communication network

    Science.gov (United States)

    Chang, Chengwu; Huang, Huiming; Liu, Hongyang; Gao, Shenghua; Cheng, Liyu

    2016-10-01

    Since the 21st century, Spatial laser communication has made a breakthrough development. Europe, the United States, Japan and other space powers have carried out the test of spatial laser communication technology on-orbit, and put forward a series of plans. In 2011, China made the first technology demonstration of satellite-ground laser communication carried by HY-2 satellite. Nowadays, in order to improve the transmission rate of spatial network, the topic of spatial laser communication network is becoming a research hotspot at home and abroad. This thesis, from the basic problem of spatial laser communication network to solve, analyzes the main difference between spatial network and ground network, which draws forth the key technology of spatial laser communication backbone network, and systematically introduces our research on aggregation, addressing, architecture of spatial network. From the perspective of technology development status and trends, the thesis proposes the development route of spatial laser communication network in stages. So as to provide reference about the development of spatial laser communication network in China.

  3. Creation of a European network dedicated to technology transfer

    CERN Multimedia

    2008-01-01

    The CERN Council recently approved the creation of a technology transfer network, whose aim will be to improve European industry’s access to the technologies developed by the particle physics community in the Member States. The gas detectors for the TOTEM experiment (GEM) offer potential for fruitful collaboration within the framework of the TT network. Many other technologies are going down the same road.The desire to set up a technology transfer network follows on from the European Strategy for Particle Physics, approved by the CERN Council on 14 July 2006 in Lisbon. In this context, special emphasis was laid on European industry’s participation in the implementation of particle physics programmes and, in particular, its access to the new technologies developed by the scientific community. It was recognised that effort needs to be put into improving the efficiency of technology transfer...

  4. 75 FR 57521 - Networking and Information Technology Research and Development (NITRD) Program: Draft NITRD 2010...

    Science.gov (United States)

    2010-09-21

    ... NATIONAL SCIENCE FOUNDATION Networking and Information Technology Research and Development (NITRD...) for Networking and Information Technology Research and Development (NITRD). ACTION: Notice, request.... SUMMARY: With this notice, the National Coordination Office for Networking and Information Technology...

  5. Enabling Technologies for Cognitive Optical Networks

    DEFF Research Database (Denmark)

    Borkowski, Robert

    Cognition is a new paradigm for optical networking, in which the network has capabilities to observe, plan, decide, and act autonomously in order to optimize the end-to-end performance and minimize the need for human supervision. This PhD thesis expands the state of the art on cognitive optical......, and machine learning algorithms that make cognition possible. Secondly, advanced optical performance monitoring (OPM) capabilities performed via digital signal processing (DSP) that provide CONs with necessary feedback information allowing for autonomous network optimization. The research results presented...... in this thesis were carried out in the framework of the EU project Cognitive Heterogeneous Reconfigurable Optical Network (CHRON), whose aim was to develop an architecture and implement a testbed of a cognitive network able to self-configure and self-optimize to efficiently use available resources. In order...

  6. WiMAX technology and network evolution

    CERN Document Server

    Etemad, Kamran

    2010-01-01

    WiMAX, the Worldwide Interoperability for Microwave Access, represents a paradigm shift in telecommunications technology. It offers the promise of cheaper, smaller, and simpler technology compared to existing broadband options such as DSL, cable, fiber, and 3G wireless.

  7. Multi-user software of radio therapeutical calculation using a computational network

    International Nuclear Information System (INIS)

    Allaucca P, J.J.; Picon C, C.; Zaharia B, M.

    1998-01-01

    It has been designed a hardware and software system for a radiotherapy Department. It runs under an Operative system platform Novell Network sharing the existing resources and of the server, it is centralized, multi-user and of greater safety. It resolves a variety of problems and calculation necessities, patient steps and administration, it is very fast and versatile, it contains a set of menus and options which may be selected with mouse, direction arrows or abbreviated keys. (Author)

  8. DATA MINING OF USERS' SOCIAL NETWORK PROFILE FOR DETERMINATION OF TYPOLOGY OF THE CONSUMER. Part I

    OpenAIRE

    Skiba S. A.; Loyko V. I.

    2015-01-01

    The article considers a new approach to the definition of the type and psycho type of consumer - social network user, using psychographics methods, data mining and statistical techniques and analytical tools. In the study, we executed testing of respondents in order to identify the properties of their socio-economic preferences. Experimental and research work aimed at solving the problem described in the article, was divided into several complementary to each other and interconnected parts. T...

  9. User Participation and Honesty in Online Rating Systems: What a Social Network Can Do

    OpenAIRE

    Davoust, Alan; Esfandiari, Babak

    2016-01-01

    An important problem with online communities in general, and online rating systems in particular, is uncooperative behavior: lack of user participation, dishonest contributions. This may be due to an incentive structure akin to a Prisoners' Dilemma (PD). We show that introducing an explicit social network to PD games fosters cooperative behavior, and use this insight to design a new aggregation technique for online rating systems. Using a dataset of ratings from Yelp, we show that our aggrega...

  10. Cyber-physical system design with sensor networking technologies

    CERN Document Server

    Zeadally, Sherali

    2016-01-01

    This book describes how wireless sensor networking technologies can help in establishing and maintaining seamless communications between the physical and cyber systems to enable efficient, secure, reliable acquisition, management, and routing of data.

  11. Psychological risk factors of addiction to social networking sites among Chinese smartphone users.

    Science.gov (United States)

    Wu, Anise M S; Cheung, Vivi I; Ku, Lisbeth; Hung, Eva P W

    2013-09-01

    Smartphones allow users to access social networking sites (SNSs) whenever and wherever they want. Such easy availability and accessibility may increase their vulnerability to addiction. Based on the social cognitive theory (SCT), we examined the impacts of outcome expectancies, self-efficacy, and impulsivity on young Chinese smartphone users' addictive tendencies toward SNSs. Two hundred seventy-seven Macau young smartphone users (116 males and 161 females; mean age = 26.62) filled out an online Chinese questionnaire concerning their usage of social networking sites via smartphones, addiction tendencies toward SNSs, impulsivity trait, outcome expectancies toward the use, and Internet self-efficacy. The findings revealed that those who spent more time on SNSs also reported higher addictive tendencies. Addictive tendencies were positively correlated with both outcome expectancies and impulsivity, but negatively associated with Internet self-efficacy. These three psychological variables explained 23% of the variance in addictive tendencies. The findings of this study suggest that, compared to demographics, psychological factors provide a better account for addictive tendencies towards SNSs among Chinese smartphone users in Macau. The three psychological risk factors were low Internet self-efficacy, favorable outcome expectancies, and high impulsivity trait. Educational campaigns with screening procedures for high-risk groups are recommended for effective prevention and treatment.

  12. An investigation into users' information security awareness on social networks in south western Nigeria

    Directory of Open Access Journals (Sweden)

    Julius O. Okesola

    2016-11-01

    Full Text Available Background: Social networks (SNs offer new and exciting opportunities for interaction among people, cutting across different stratum of the society and providing a ubiquitous mechanism that supports a wide variety of activities. They are at the same time being exploited by criminals to fraudulently obtain information from unsuspecting users. Unfortunately, the seamless communication and semblance of safety assumed by most users make them oblivious to the potential online dangers. Objective: Using quantitative methods on selected social sites, this study empirically examined the information security awareness of SN users in south western Nigeria. Method: A self-designed research instrument was administered for data collection while descriptive and inferential statistics were employed using chi-square, cross-tabulation and t-test for data analysis and result interpretation. Result: Findings from the analysed data suggest that the risk perception vary among male and female SN users and that the general perception of risks regarding SN usage is also very low. Conclusion: Adequate security awareness coupled with detailed legal measures are required to keep SNs secured. However, an individual is duly responsible for the habit of ignoring potential risks posed by the networks.

  13. User-centred design as an important component of technological development

    Directory of Open Access Journals (Sweden)

    Jankowski Natalie

    2017-03-01

    Full Text Available New technologies can be implemented in clinical rehabilitation processes or to close the gap in health care provision by transferring them to the patients’ home. Successful use can only be achieved under the assumption that the technology is accepted by its users. The involvement of users in iterative development processes is to be shown to increase the quality of health care systems and to prevent refusal. In this review potentials of user acceptance and satisfaction surveys in the development of stroke rehabilitation systems are discussed. The surveys are conducted as a method for improving the ongoing design process of innovative technical systems developed in the BMBF funded project “BeMobil”.

  14. Social and parasocial relationships on social network sites and their differential relationships with users' psychological well-being.

    Science.gov (United States)

    Baek, Young Min; Bae, Young; Jang, Hyunmi

    2013-07-01

    With the advent of social network sites (SNSs), people can efficiently maintain preexisting social relationships and make online friendships without offline encounters. While such technological features of SNSs hold a variety of potential for individual and collective benefits, some scholars warn that use of SNSs might lead to socially negative consequences, such as social isolation, erosion of social cohesion, or SNS addiction. This study distinguishes types of SNS relationships, and investigates their relationships with social isolation, interpersonal trust, and SNS addiction. We classify SNS relationships into two types: (a) social relationships based on reciprocity between a user and his/her friends, and (b) parasocial relationships in which an ordinary user is aware of activities of a celebrity (e.g., famous actors, athletes, and others) but not vice versa. Based on achievements in studies of media effect and social psychology, we constructed a set of hypotheses, and tested them using a subsample of SNS users drawn from representative survey data in South Korea. We found that dependency on parasocial relationships is positively related with loneliness but negatively correlated with interpersonal distrust, while dependency on social relationship is negatively correlated with loneliness but positively related with trust. However, more dependency on both social and parasocial relationships are positively related with SNS addiction. Implications based on findings are also discussed.

  15. Competitiveness of Second Generation Biofuel Feedstocks: Role of Technology and Policy (2010 JGI User Meeting)

    Energy Technology Data Exchange (ETDEWEB)

    Khanna, Madhu

    2010-03-26

    Madhu Khanna from the University of Illinois at Urbana-Champaign and the Energy Biosciences Institute on Competitiveness of Second Generation Biofuel Feedstocks: Role of Technology and Policy on March 25, 2010 at the 5th Annual DOE JGI User Meeting.

  16. Creative Teaching and Learning Strategies for Novice Users of Mobile Technologies

    Science.gov (United States)

    Masters, Jennifer

    2013-01-01

    This paper addresses perspectives of creative teaching and learning strategies in the new learning context of mobile technology, particularly for novice learners. The discussion presented here is framed by two case studies and uses an ethnographical approach, informed by participant observation to consider the experiences of users of mobile…

  17. Assessment of Application Technology of Natural User Interfaces in the Creation of a Virtual Chemical Laboratory

    Science.gov (United States)

    Jagodzinski, Piotr; Wolski, Robert

    2015-01-01

    Natural User Interfaces (NUI) are now widely used in electronic devices such as smartphones, tablets and gaming consoles. We have tried to apply this technology in the teaching of chemistry in middle school and high school. A virtual chemical laboratory was developed in which students can simulate the performance of laboratory activities similar…

  18. Understanding social acceptability of arsenic-safe technologies in rural Bangladesh: A user-oriented analysis

    NARCIS (Netherlands)

    Kundu, D.K.; Gupta, A.; Mol, A.P.J.; Nasreen, M.

    2016-01-01

    Contamination of shallow tube well drinking water by naturally occurring arsenic is a severe societal and human health challenge in Bangladesh. Multiple technological interventions seeking to ameliorate the problem face hurdles in securing social acceptance, i.e. a willingness of users to receive

  19. Knowledge network for medical technology management in Mexico.

    Science.gov (United States)

    Licona, Fabiola Martínez; Leehan, Joaquín Azpiroz; Méndez, Miguel Cadena; Yuriar, Salvador Duarte; Salazar, Raúl Molina; Gilmore, Amador Terán

    2009-10-01

    The role of biomedical engineers (BMEs) has changed widely over the years, from managing a group of technicians to the planning of large installations and the management of medical technology countrywide. As the technology has advanced, the competence of BMEs has been challenged because it is no longer possible to be an expert in every component of the technology involved in running a hospital. Our approach has been to form a network of professionals that are experts in different fields related to medical technology, where work is coordinated to provide high quality services at the planning and execution stages of projects related to medical technology. A study of the procedures involved in the procurement of medical technology has been carried out over the years. These experiences have been compared with several case studies where the approach to problem solving in this area has been multidisciplinary. Planning and execution phases of projects involving medical technology management have been identified. After several instances of collaboration among experts from different fields, a network for management of healthcare technology has been formed at our institution that incorporates the experience from different departments that were dealing separately with projects involving medical technology. This network has led us to propose this approach to solve medical technology management projects, where the strengths of each subgroup complement each other. This structure will lead to a more integrated approach to healthcare technology management and will ensure higher quality solutions.

  20. Cryptanalysis and security improvements of 'two-factor user authentication in wireless sensor networks'.

    Science.gov (United States)

    Khan, Muhammad Khurram; Alghathbar, Khaled

    2010-01-01

    User authentication in wireless sensor networks (WSN) is a critical security issue due to their unattended and hostile deployment in the field. Since sensor nodes are equipped with limited computing power, storage, and communication modules; authenticating remote users in such resource-constrained environments is a paramount security concern. Recently, M.L. Das proposed a two-factor user authentication scheme in WSNs and claimed that his scheme is secure against different kinds of attack. However, in this paper, we show that the M.L. Das-scheme has some critical security pitfalls and cannot be recommended for real applications. We point out that in his scheme: users cannot change/update their passwords, it does not provide mutual authentication between gateway node and sensor node, and is vulnerable to gateway node bypassing attack and privileged-insider attack. To overcome the inherent security weaknesses of the M.L. Das-scheme, we propose improvements and security patches that attempt to fix the susceptibilities of his scheme. The proposed security improvements can be incorporated in the M.L. Das-scheme for achieving a more secure and robust two-factor user authentication in WSNs.

  1. Chaos in a dynamic model of urban transportation network flow based on user equilibrium states

    International Nuclear Information System (INIS)

    Xu Meng; Gao Ziyou

    2009-01-01

    In this study, we investigate the dynamical behavior of network traffic flow. We first build a two-stage mathematical model to analyze the complex behavior of network flow, a dynamical model, which is based on the dynamical gravity model proposed by Dendrinos and Sonis [Dendrinos DS, Sonis M. Chaos and social-spatial dynamic. Berlin: Springer-Verlag; 1990] is used to estimate the number of trips. Considering the fact that the Origin-Destination (O-D) trip cost in the traffic network is hard to express as a functional form, in the second stage, the user equilibrium network assignment model was used to estimate the trip cost, which is the minimum cost of used path when user equilibrium (UE) conditions are satisfied. It is important to use UE to estimate the O-D cost, since a connection is built among link flow, path flow, and O-D flow. The dynamical model describes the variations of O-D flows over discrete time periods, such as each day and each week. It is shown that even in a system with dimensions equal to two, chaos phenomenon still exists. A 'Chaos Propagation' phenomenon is found in the given model.

  2. Impact of Information and Communication Technology on Information Seeking Behavior of Users in Astronomy and Astrophysics Centers of India: A Survey

    Science.gov (United States)

    Sahu, H. K.; Singh, S. N.

    2010-10-01

    This study is based on a survey designed to determine the Information Seeking Behavior (ISB) of Astronomy and Astrophysics users in India. The main objective of the study is to determine the sources consulted and the general pattern of the information-gathering system of users and the impact of Information and Communication Technology (ICT) on the Astronomy and Astrophysics user's Information Seeking Behavior. It examines various Information and Communication Technology-based resources and methods of access and use. A descriptive sample stratified method has been used and data was collected using a questionnaire as the main tool. The response rate was 72%. Descriptive statistics were also employed and data have been presented in tables and graphs. The study is supported by earlier studies. It shows that Astronomy and Astrophysics users have developed a unique Information Seeking Behavior to carry out their education and research. The vast majority of respondents reported that more information is available from a variety of e-resources. Consequently, they are able to devote more time to seek out relevant information in the current Information and Communication Technology scenario. The study also indicates that respondents use a variety of information resources including e-resources for teaching and research. Books and online databases such as the NASA Astrophysics Data System (ADS) were considered more important as formal sources of information. E-mail and face-to-face communications are used extensively by users as informal sources of information. It also reveals that despite the presence of electronic sources, Astronomy and Astrophysics users are still using printed materials. This study should to help to improve various Information and Communication Technology-based services. It also suggests that GOI should adopt Information and Communication Technology-based Information Centers and Libraries services and recommends a network-based model for Astronomy and

  3. Digital video technologies and their network requirements

    Energy Technology Data Exchange (ETDEWEB)

    R. P. Tsang; H. Y. Chen; J. M. Brandt; J. A. Hutchins

    1999-11-01

    Coded digital video signals are considered to be one of the most difficult data types to transport due to their real-time requirements and high bit rate variability. In this study, the authors discuss the coding mechanisms incorporated by the major compression standards bodies, i.e., JPEG and MPEG, as well as more advanced coding mechanisms such as wavelet and fractal techniques. The relationship between the applications which use these coding schemes and their network requirements are the major focus of this study. Specifically, the authors relate network latency, channel transmission reliability, random access speed, buffering and network bandwidth with the various coding techniques as a function of the applications which use them. Such applications include High-Definition Television, Video Conferencing, Computer-Supported Collaborative Work (CSCW), and Medical Imaging.

  4. Gigabit network technology. Final technical report

    Energy Technology Data Exchange (ETDEWEB)

    Davenport, C.M.C. [ed.

    1996-10-01

    Current digital networks are evolving toward distributed multimedia with a wide variety of applications with individual data rates ranging from kb/sec to tens and hundreds of Mb/sec. Link speed requirements are pushing into the Gb/sec range and beyond the envelop of electronic networking capabilities. There is a vast amount of untapped bandwidth available in the low-attenuation communication bands of an optical fiber. The capacity in one fiber thread is enough to carry more than two thousand times as much information as all the current radio and microwave frequencies. And while fiber optics has replaced copper wire as the transmission medium of choice, the communication capacity of conventional fiber optic networks is ultimately limited by electronic processing speeds.

  5. Use of health technology assessment in decision making: coresponsibility of users and producers?

    Science.gov (United States)

    Hivon, Myriam; Lehoux, Pascale; Denis, Jean-Louis; Tailliez, Stéphanie

    2005-01-01

    Health technology assessment (HTA) is a policy-oriented form of research designed to inform decision-makers on the introduction, use, and dissemination of health technology. Whereas research on knowledge transfer has focused on knowledge producers, little attention has been given to the user's perspective. This study examines how health-care provider, administrator, and patient associations across Canada use HTA reports and the limitations they encounter when accessing and using scientific knowledge. This study draws from semistructured interviews (n=42) conducted with three types of user, located in British Columbia, Alberta, Saskatchewan, Ontario, and Quebec. Applying well-established conceptual categories in knowledge utilization research, our qualitative analyses sought to define more precisely how HTA is used by interviewees as well as the most significant barriers they encounter. The vast majority of users recognize the usefulness and credibility of HTA reports. Of interest, the way they use HTA takes different forms. Although administrators and health-care providers are in a better position than patient associations to act directly on HTA messages--making an instrumental use of HTA--we also found conceptual and symbolic uses across all groups. Our results also indicate that significant organizational, scientific, and material limitations hinder the use of scientific evidence. Overcoming such barriers requires a greater commitment from both HTA producers and users. This study argues that, to ensure better uptake of HTA, it should become a shared responsibility between HTA producers and various types of user.

  6. Perspectives on next-generation technology for environmental sensor networks

    Science.gov (United States)

    Barbara J. Benson; Barbara J. Bond; Michael P. Hamilton; Russell K. Monson; Richard. Han

    2009-01-01

    Sensor networks promise to transform and expand environmental science. However, many technological difficulties must be overcome to achieve this potential. Partnerships of ecologists with computer scientists and engineers are critical in meeting these challenges. Technological issues include promoting innovation in new sensor design, incorporating power optimization...

  7. The dynamics of injection drug users' personal networks and HIV risk behaviors.

    Science.gov (United States)

    Costenbader, Elizabeth C; Astone, Nan M; Latkin, Carl A

    2006-07-01

    While studies of the social networks of injection drug users (IDUs) have provided insight into how the structures of interpersonal relationships among IDUs affect HIV risk behaviors, the majority of these studies have been cross-sectional. The present study examined the dynamics of IDUs' social networks and HIV risk behaviors over time. Using data from a longitudinal HIV-intervention study conducted in Baltimore, MD, this study assessed changes in the composition of the personal networks of 409 IDUs. We used a multi-nomial logistic regression analysis to assess the association between changes in network composition and simultaneous changes in levels of injection HIV risk behaviors. Using the regression parameters generated by the multi-nomial model, we estimated the predicted probability of being in each of four HIV risk behavior change groups. Compared to the base case, individuals who reported an entirely new set of drug-using network contacts at follow-up were more than three times as likely to be in the increasing risk group. In contrast, reporting all new non-drug-using contacts at follow-up increased the likelihood of being in the stable low-risk group by almost 50% and decreased the probability of being in the consistently high-risk group by more than 70%. The findings from this study show that, over and above IDUs' baseline characteristics, changes in their personal networks are associated with changes in individuals' risky injection behaviors. They also suggest that interventions aimed at reducing HIV risk among IDUs might benefit from increasing IDUs' social contacts with individuals who are not drug users.

  8. User Adaptive and Context-Aware Smart Home Using Pervasive and Semantic Technologies

    Directory of Open Access Journals (Sweden)

    Aggeliki Vlachostergiou

    2016-01-01

    Full Text Available Ubiquitous Computing is moving the interaction away from the human-computer paradigm and towards the creation of smart environments that users and things, from the IoT perspective, interact with. User modeling and adaptation is consistently present having the human user as a constant but pervasive interaction introduces the need for context incorporation towards context-aware smart environments. The current article discusses both aspects of the user modeling and adaptation as well as context awareness and incorporation into the smart home domain. Users are modeled as fuzzy personas and these models are semantically related. Context information is collected via sensors and corresponds to various aspects of the pervasive interaction such as temperature and humidity, but also smart city sensors and services. This context information enhances the smart home environment via the incorporation of user defined home rules. Semantic Web technologies support the knowledge representation of this ecosystem while the overall architecture has been experimentally verified using input from the SmartSantander smart city and applying it to the SandS smart home within FIRE and FIWARE frameworks.

  9. Technology Infrastructure, Analyst (Network, Video and ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Job Summary. Under the supervision of the Manager of Techology Services (TS), the Network/Telecommunications Analyst plays a critical role in service delivery as part of the TS team responsible for the day-to-day operation and maintenance of the Centre's various infrastructure systems in Headquarters and the Regional ...

  10. Applying Trusted Network Technology To Process Control Systems

    Science.gov (United States)

    Okhravi, Hamed; Nicol, David

    Interconnections between process control networks and enterprise networks expose instrumentation and control systems and the critical infrastructure components they operate to a variety of cyber attacks. Several architectural standards and security best practices have been proposed for industrial control systems. However, they are based on older architectures and do not leverage the latest hardware and software technologies. This paper describes new technologies that can be applied to the design of next generation security architectures for industrial control systems. The technologies are discussed along with their security benefits and design trade-offs.

  11. Technologies for network-centric C4ISR

    Science.gov (United States)

    Dunkelberger, Kirk A.

    2003-07-01

    Three technologies form the heart of any network-centric command, control, communication, intelligence, surveillance, and reconnaissance (C4ISR) system: distributed processing, reconfigurable networking, and distributed resource management. Distributed processing, enabled by automated federation, mobile code, intelligent process allocation, dynamic multiprocessing groups, check pointing, and other capabilities creates a virtual peer-to-peer computing network across the force. Reconfigurable networking, consisting of content-based information exchange, dynamic ad-hoc routing, information operations (perception management) and other component technologies forms the interconnect fabric for fault tolerant inter processor and node communication. Distributed resource management, which provides the means for distributed cooperative sensor management, foe sensor utilization, opportunistic collection, symbiotic inductive/deductive reasoning and other applications provides the canonical algorithms for network-centric enterprises and warfare. This paper introduces these three core technologies and briefly discusses a sampling of their component technologies and their individual contributions to network-centric enterprises and warfare. Based on the implied requirements, two new algorithms are defined and characterized which provide critical building blocks for network centricity: distributed asynchronous auctioning and predictive dynamic source routing. The first provides a reliable, efficient, effective approach for near-optimal assignment problems; the algorithm has been demonstrated to be a viable implementation for ad-hoc command and control, object/sensor pairing, and weapon/target assignment. The second is founded on traditional dynamic source routing (from mobile ad-hoc networking), but leverages the results of ad-hoc command and control (from the contributed auctioning algorithm) into significant increases in connection reliability through forward prediction. Emphasis

  12. The Relationship Between Attachment Styles, Self-Monitoring and Cybercrime in Social Network Users.

    Science.gov (United States)

    Yaghoobi, Abolghasem; Mohammadzade, Serwa; Chegini, Ali Asghar; Yarmohammadi Vasel, Mosaeib; Zoghi Paidar, Mohammad Reza

    2016-09-01

    The anonymity in the cyberspace environment, as well as the rapid advent of and improvements to online activities has increased cybercrime. The aim of this paper was to survey the relationship between attachment styles, self-monitoring and cybercrime in social network users. The Collins and Read Adult Attachment Scale, and the Snyder self-monitoring and cybercrime scales were sent to 500 social network users. Of these, 203 users (103 men and 100 women) filled out the questionnaires. The results showed that women achieved higher scores in self-monitoring and the anxious attachment style, and men achieved higher scores in cybercrime and the anxious attachment style. There was a negative correlation between self-monitoring and cybercrime, and the anxious attachment style had a positive correlation with cybercrime and a negative correlation with self-monitoring. The secure attachment style had a positive correlation with self-monitoring and a negative correlation with cybercrime. The dependent attachment style had a positive correlation with self-monitoring and a negative correlation with cybercrime. All correlations were significant. Attachment styles have significant relationships with both self-monitoring and cybercrime. Self-monitoring and attachment styles are significant predictors of cybercrimes.

  13. Three-Factor User Authentication and Key Agreement Using Elliptic Curve Cryptosystem in Wireless Sensor Networks.

    Science.gov (United States)

    Park, YoHan; Park, YoungHo

    2016-12-14

    Secure communication is a significant issue in wireless sensor networks. User authentication and key agreement are essential for providing a secure system, especially in user-oriented mobile services. It is also necessary to protect the identity of each individual in wireless environments to avoid personal privacy concerns. Many authentication and key agreement schemes utilize a smart card in addition to a password to support security functionalities. However, these schemes often fail to provide security along with privacy. In 2015, Chang et al. analyzed the security vulnerabilities of previous schemes and presented the two-factor authentication scheme that provided user privacy by using dynamic identities. However, when we cryptanalyzed Chang et al.'s scheme, we found that it does not provide sufficient security for wireless sensor networks and fails to provide accurate password updates. This paper proposes a security-enhanced authentication and key agreement scheme to overcome these security weaknesses using biometric information and an elliptic curve cryptosystem. We analyze the security of the proposed scheme against various attacks and check its viability in the mobile environment.

  14. An Enhanced Three-Factor User Authentication Scheme Using Elliptic Curve Cryptosystem for Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Chenyu Wang

    2017-12-01

    Full Text Available As an essential part of Internet of Things (IoT, wireless sensor networks (WSNs have touched every aspect of our lives, such as health monitoring, environmental monitoring and traffic monitoring. However, due to its openness, wireless sensor networks are vulnerable to various security threats. User authentication, as the first fundamental step to protect systems from various attacks, has attracted much attention. Numerous user authentication protocols armed with formal proof are springing up. Recently, two biometric-based schemes were proposed with confidence to be resistant to the known attacks including offline dictionary attack, impersonation attack and so on. However, after a scrutinization of these two schemes, we found them not secure enough as claimed, and then demonstrated that these schemes suffer from various attacks, such as offline dictionary attack, impersonation attack, no user anonymity, no forward secrecy, etc. Furthermore, we proposed an enhanced scheme to overcome the identified weaknesses, and proved its security via Burrows–Abadi–Needham (BAN logic and the heuristic analysis. Finally, we compared our scheme with other related schemes, and the results showed the superiority of our scheme.

  15. An Enhanced Three-Factor User Authentication Scheme Using Elliptic Curve Cryptosystem for Wireless Sensor Networks.

    Science.gov (United States)

    Wang, Chenyu; Xu, Guoai; Sun, Jing

    2017-12-19

    As an essential part of Internet of Things (IoT), wireless sensor networks (WSNs) have touched every aspect of our lives, such as health monitoring, environmental monitoring and traffic monitoring. However, due to its openness, wireless sensor networks are vulnerable to various security threats. User authentication, as the first fundamental step to protect systems from various attacks, has attracted much attention. Numerous user authentication protocols armed with formal proof are springing up. Recently, two biometric-based schemes were proposed with confidence to be resistant to the known attacks including offline dictionary attack, impersonation attack and so on. However, after a scrutinization of these two schemes, we found them not secure enough as claimed, and then demonstrated that these schemes suffer from various attacks, such as offline dictionary attack, impersonation attack, no user anonymity, no forward secrecy, etc. Furthermore, we proposed an enhanced scheme to overcome the identified weaknesses, and proved its security via Burrows-Abadi-Needham (BAN) logic and the heuristic analysis. Finally, we compared our scheme with other related schemes, and the results showed the superiority of our scheme.

  16. Technology acceptance and purchase intention towards 3G technology among millennial smart phone users: A case of Pakistan

    Directory of Open Access Journals (Sweden)

    Muhammad Jasim

    2016-11-01

    Full Text Available This study aims to investigate the technology acceptance and purchase intention for Third Generation (3G technology in Pakistan’s telecom sector. In such respect, Technology Acceptance Model (TAM has been used to find the effects of the independent variables (Perceived Usefulness, Perceived Ease of Use, Perceived Value, Perceived Enjoyment, Personal Innovativeness and Price on dependent variable (purchase intention. The study population consisted of smartphone users among Millennials in district Haripur-a region in transition towards urbanization. 200 respondents provided the useable data. The results of the study show that perceived usefulness, perceived ease of use, perceived value, perceived enjoyment, personal innovativeness, and price have a significant and positive relationship with purchase intention which validates the growing acceptance of advanced technologies in such regions.

  17. Few Things About Idioms: Understanding Idioms and Its Users in the Twitter Online Social Network

    Science.gov (United States)

    2015-05-22

    clubs Liverpool and Chelsea) is accompanied by the hashtag #Torres which indicates a player who is a part of the match. On the other hand, Twitter...faves friend sports wwe game 5sos band show news social iphone love ily people football wrestling season justin album music tech media ios fun luke hobby...school soccer cricket football luke idols album software business apple trends(sports, entertainment, technology) are very popular users, which includes

  18. Applying Distributed Constraint Optimization Approach to the User Association Problem in Heterogeneous Networks.

    Science.gov (United States)

    Duan, Peibo; Zhang, Changsheng; Mao, Guoqiang; Zhang, Bin

    2017-09-22

    User association has emerged as a distributed resource allocation problem in the heterogeneous networks (HetNets). Although an approximate solution is obtainable using the approaches like combinatorial optimization and game theory-based schemes, these techniques can be easily trapped in local optima. Furthermore, the lack of exploring the relation between the quality of the solution and the parameters in the HetNet [e.g., the number of users and base stations (BSs)], at what levels, impairs the practicability of deploying these approaches in a real world environment. To address these issues, this paper investigates how to model the problem as a distributed constraint optimization problem (DCOP) from the point of the view of the multiagent system. More specifically, we develop two models named each connection as variable (ECAV) and each BS and user as variable (EBUAV). Hereinafter, we propose a DCOP solver which not only sets up the model in a distributed way but also enables us to efficiently obtain the solution by means of a complete DCOP algorithm based on distributed message-passing. Naturally, both theoretical analysis and simulation show that different qualitative solutions can be obtained in terms of an introduced parameter η which has a close relation with the parameters in the HetNet. It is also apparent that there is 6% improvement on the throughput by the DCOP solver comparing with other counterparts when η=3. Particularly, it demonstrates up to 18% increase in the ability to make BSs service more users when the number of users is above 200 while the available resource blocks (RBs) are limited. In addition, it appears that the distribution of RBs allocated to users by BSs is better with the variation of the volume of RBs at the macro BS.

  19. Technological, biological, and acoustical constraints to music perception in cochlear implant users.

    Science.gov (United States)

    Limb, Charles J; Roy, Alexis T

    2014-02-01

    Despite advances in technology, the ability to perceive music remains limited for many cochlear implant users. This paper reviews the technological, biological, and acoustical constraints that make music an especially challenging stimulus for cochlear implant users, while highlighting recent research efforts to overcome these shortcomings. The limitations of cochlear implant devices, which have been optimized for speech comprehension, become evident when applied to music, particularly with regards to inadequate spectral, fine-temporal, and dynamic range representation. Beyond the impoverished information transmitted by the device itself, both peripheral and central auditory nervous system deficits are seen in the presence of sensorineural hearing loss, such as auditory nerve degeneration and abnormal auditory cortex activation. These technological and biological constraints to effective music perception are further compounded by the complexity of the acoustical features of music itself that require the perceptual integration of varying rhythmic, melodic, harmonic, and timbral elements of sound. Cochlear implant users not only have difficulty perceiving spectral components individually (leading to fundamental disruptions in perception of pitch, melody, and harmony) but also display deficits with higher perceptual integration tasks required for music perception, such as auditory stream segregation. Despite these current limitations, focused musical training programs, new assessment methods, and improvements in the representation and transmission of the complex acoustical features of music through technological innovation offer the potential for significant advancements in cochlear implant-mediated music perception. Copyright © 2013 Elsevier B.V. All rights reserved.

  20. Application of local area network technology in an engineering environment

    International Nuclear Information System (INIS)

    Powell, A.D.; Sokolowski, M.A.

    1990-01-01

    This paper reports on the application of local area network technology in an engineering environment. Mobil Research and Development Corporation Engineering, Dallas, texas has installed a local area network (LAN) linking over 85 microcomputers. This network, which has been in existence for more than three years, provides common access by all engineers to quality output devices such as laser printers and multi-color pen plotters; IBM mainframe connections; electronic mail and file transfer; and common engineering program. The network has been expanded via a wide area ethernet network to link the Dallas location with a functionally equivalent LAN of over 400 microcomputers in Princeton, N.J. Additionally, engineers on assignment at remote areas in Europe, U.S., Africa and project task forces have dial-in access to the network via telephone lines

  1. A Sensitive Secondary Users Selection Algorithm for Cognitive Radio Ad Hoc Networks

    Directory of Open Access Journals (Sweden)

    Aohan Li

    2016-03-01

    Full Text Available Secondary Users (SUs are allowed to use the temporarily unused licensed spectrum without disturbing Primary Users (PUs in Cognitive Radio Ad Hoc Networks (CRAHNs. Existing architectures for CRAHNs impose energy-consuming Cognitive Radios (CRs on SUs. However, the advanced CRs will increase energy cost for their cognitive functionalities, which is undesirable for the battery powered devices. A new architecture referred to as spectral Requirement-based CRAHN (RCRAHN is proposed to enhance energy efficiency for CRAHNs in this paper. In RCRAHNs, only parts of SUs are equipped with CRs. SUs equipped with CRs are referred to as Cognitive Radio Users (CRUs. To further enhance energy efficiency of CRAHNs, we aim to select minimum CRUs to sense available spectrum. A non-linear programming problem is mathematically formulated under the constraints of energy efficiency and real-time. Considering the NP-hardness of the problem, a framework of a heuristic algorithm referred to as Sensitive Secondary Users Selection (SSUS was designed to compute the near-optimal solutions. The simulation results demonstrate that SSUS not only improves the energy efficiency, but also achieves satisfied performances in end-to-end delay and communication reliability.

  2. Web-based metabolic network visualization with a zooming user interface

    Directory of Open Access Journals (Sweden)

    Karp Peter D

    2011-05-01

    Full Text Available Abstract Background Displaying complex metabolic-map diagrams, for Web browsers, and allowing users to interact with them for querying and overlaying expression data over them is challenging. Description We present a Web-based metabolic-map diagram, which can be interactively explored by the user, called the Cellular Overview. The main characteristic of this application is the zooming user interface enabling the user to focus on appropriate granularities of the network at will. Various searching commands are available to visually highlight sets of reactions, pathways, enzymes, metabolites, and so on. Expression data from single or multiple experiments can be overlaid on the diagram, which we call the Omics Viewer capability. The application provides Web services to highlight the diagram and to invoke the Omics Viewer. This application is entirely written in JavaScript for the client browsers and connect to a Pathway Tools Web server to retrieve data and diagrams. It uses the OpenLayers library to display tiled diagrams. Conclusions This new online tool is capable of displaying large and complex metabolic-map diagrams in a very interactive manner. This application is available as part of the Pathway Tools software that powers multiple metabolic databases including Biocyc.org: The Cellular Overview is accessible under the Tools menu.

  3. A Sensitive Secondary Users Selection Algorithm for Cognitive Radio Ad Hoc Networks.

    Science.gov (United States)

    Li, Aohan; Han, Guangjie; Wan, Liangtian; Shu, Lei

    2016-03-26

    Secondary Users (SUs) are allowed to use the temporarily unused licensed spectrum without disturbing Primary Users (PUs) in Cognitive Radio Ad Hoc Networks (CRAHNs). Existing architectures for CRAHNs impose energy-consuming Cognitive Radios (CRs) on SUs. However, the advanced CRs will increase energy cost for their cognitive functionalities, which is undesirable for the battery powered devices. A new architecture referred to as spectral Requirement-based CRAHN (RCRAHN) is proposed to enhance energy efficiency for CRAHNs in this paper. In RCRAHNs, only parts of SUs are equipped with CRs. SUs equipped with CRs are referred to as Cognitive Radio Users (CRUs). To further enhance energy efficiency of CRAHNs, we aim to select minimum CRUs to sense available spectrum. A non-linear programming problem is mathematically formulated under the constraints of energy efficiency and real-time. Considering the NP-hardness of the problem, a framework of a heuristic algorithm referred to as Sensitive Secondary Users Selection (SSUS) was designed to compute the near-optimal solutions. The simulation results demonstrate that SSUS not only improves the energy efficiency, but also achieves satisfied performances in end-to-end delay and communication reliability.

  4. Impact of Users Identities and Access Conditions on Downlink Performance in Closed Small-Cell Networks

    KAUST Repository

    Radaydeh, Redha

    2015-05-26

    This paper investigates the effect of various operation parameters on the downlink user performance in overlaid small-cell networks. The case study considers closed-access small cells (e.g., femtocells), wherein only active authorized user equipments (UEs) can be served, and each of which is allocated single downlink channel at a time. On the other hand, the macrocell base station can unconditionally serve macrocell UEs that exist inside its coverage space. The available channels can be shared simultaneously in the macrocell network and the femtocell network. Moreover, a channel can be reused only at the macrocell base station. The analysis provides quantitative approaches to model UEs identities, their likelihoods of being active, and their likelihoods of producing interference, considering UEs classifications, locations, and access capabilities. Moreover, it develops models for various interference sources observed from effective interference femtocells, considering femtocells capacities and operation conditions. The associated formulations to describe a desired UE performance and the impact of the number of available channels as well as the adopted channel assignment approach are thoroughly investigated. The results are generally presented for any channel models of interference sources as well as the desired source of the served UE. Moreover, specific channel models are then adopted, for which generalized closedform analytical results for the desired UE outage probability performance are obtained. Numerical and simulation results are presented to further clarify the main outcomes of the developed analysis.

  5. Harvesting full-duplex rate gains in cellular networks with half-duplex user terminals

    KAUST Repository

    AlAmmouri, Ahmad

    2016-07-26

    Full-Duplex (FD) transceivers may be expensive in terms of complexity, power consumption, and price to be implemented in all user terminals. Therefore, techniques to exploit in-band full-duplex communication with FD base stations (BSs) and half-duplex (HD) users\\' equipment (UEs) are required. In this context, 3-node topology (3NT) has been recently proposed for FD BSs to reuse the uplink (UL) and downlink (DL) channels with HD terminals within the same cell. In this paper, we present a tractable mathematical framework, based on stochastic geometry, for 3NT in cellular networks. To this end, we propose a design paradigm via pulse-shaping and partial overlap between UL and DL channels to maximize the harvested rate gains in 3NT. The results show that 3NT achieves a close performance to networks with FD BSs and FD UEs, denoted by 2-node topology (2NT) networks. A maximum of 5% rate loss is reported when 3NT is compared to 2NT with efficient self-interference cancellation (SIC). If the SIC in 2NT is not efficient, 3NT highly outperforms 2NT. Consequently, we conclude that, irrespective to the UE duplexing scheme, it is sufficient to have FD BSs to harvest FD rate gains.

  6. Research and Design of Dynamic Migration Access Control Technology Based on Heterogeneous Network

    Directory of Open Access Journals (Sweden)

    Wang Feng

    2017-01-01

    Full Text Available With the continuous development of wireless networks, the amount of privacy services in heterogeneous mobile networks is increasing, such as information storage, user access, and so on. Access control security issues for heterogeneous mobile radio network, this paper proposes a dynamic migration access control technology based on heterogeneous network. Through the system architecture of the mutual trust system, we can understand the real-time mobile node failure or abnormal state. To make the service can be terminated for the node. And adopt the 802.1X authentication way to improve the security of the system. Finally, it by combining the actual running test data, the trust update algorithm of the system is optimized to reduce the actual security threats in the environment. Experiments show that the system’s anti-attack, the success rate of access, bit error rate is in line with the expected results. This system can effectively reduce the system authentication information is illegally obtained after the network security protection mechanism failure and reduce the risk of user data leakage.

  7. A Network Analysis Model for Selecting Sustainable Technology

    Directory of Open Access Journals (Sweden)

    Sangsung Park

    2015-09-01

    Full Text Available Most companies develop technologies to improve their competitiveness in the marketplace. Typically, they then patent these technologies around the world in order to protect their intellectual property. Other companies may use patented technologies to develop new products, but must pay royalties to the patent holders or owners. Should they fail to do so, this can result in legal disputes in the form of patent infringement actions between companies. To avoid such situations, companies attempt to research and develop necessary technologies before their competitors do so. An important part of this process is analyzing existing patent documents in order to identify emerging technologies. In such analyses, extracting sustainable technology from patent data is important, because sustainable technology drives technological competition among companies and, thus, the development of new technologies. In addition, selecting sustainable technologies makes it possible to plan their R&D (research and development efficiently. In this study, we propose a network model that can be used to select the sustainable technology from patent documents, based on the centrality and degree of a social network analysis. To verify the performance of the proposed model, we carry out a case study using actual patent data from patent databases.

  8. Stochastic User Equilibrium Assignment in Schedule-Based Transit Networks with Capacity Constraints

    Directory of Open Access Journals (Sweden)

    Wangtu Xu

    2012-01-01

    Full Text Available This paper proposes a stochastic user equilibrium (SUE assignment model for a schedule-based transit network with capacity constraint. We consider a situation in which passengers do not have the full knowledge about the condition of the network and select paths that minimize a generalized cost function encompassing five components: (1 ride time, which is composed of in-vehicle and waiting times, (2 overload delay, (3 fare, (4 transfer constraints, and (5 departure time difference. We split passenger demands among connections which are the space-time paths between OD pairs of the network. All transit vehicles have a fixed capacity and operate according to some preset timetables. When the capacity constraint of the transit line segment is reached, we show that the Lagrange multipliers of the mathematical programming problem are equivalent to the equilibrium passenger overload delay in the congested transit network. The proposed model can simultaneously predict how passengers choose their transit vehicles to minimize their travel costs and estimate the associated costs in a schedule-based congested transit network. A numerical example is used to illustrate the performance of the proposed model.

  9. Primary User Localization Algorithm Based on Compressive Sensing in Cognitive Radio Networks

    Directory of Open Access Journals (Sweden)

    Fang Ye

    2016-04-01

    Full Text Available In order to locate source signal more accurately in authorized frequency bands, a novel primary user localization algorithm based on compressive sensing (PU-CSL in cognitive radio networks (CRNs is proposed in this paper. In comparison to existing centroid locating algorithms, PU-CSL shows higher locating accuracy for integrally exploring correlation between source signal and secondary users (SUs. Energy detection is first adopted for collecting the energy fingerprint of source signal at each SU, then degree of correlation between source signal and SUs is reconstructed based on compressive sensing (CS, which determines weights of centroid coordinates. A weighted centroid scheme is finally utilized to estimate source position. Simulation results show that PU-CSL has smaller maximum error of positioning and root-mean-square error. Moreover, the proposed PU-CSL algorithm possess excellent location accuracy and strong anti-noise performance.

  10. A Neural Network Approach to Intention Modeling for User-Adapted Conversational Agents

    Directory of Open Access Journals (Sweden)

    David Griol

    2016-01-01

    Full Text Available Spoken dialogue systems have been proposed to enable a more natural and intuitive interaction with the environment and human-computer interfaces. In this contribution, we present a framework based on neural networks that allows modeling of the user’s intention during the dialogue and uses this prediction to dynamically adapt the dialogue model of the system taking into consideration the user’s needs and preferences. We have evaluated our proposal to develop a user-adapted spoken dialogue system that facilitates tourist information and services and provide a detailed discussion of the positive influence of our proposal in the success of the interaction, the information and services provided, and the quality perceived by the users.

  11. The dynamical modeling and simulation analysis of the recommendation on the user-movie network

    Science.gov (United States)

    Zhang, Shujuan; Jin, Zhen; Zhang, Juan

    2016-12-01

    At present, most research about the recommender system is based on graph theory and algebraic methods, but these methods cannot predict the evolution of the system with time under the recommendation method, and cannot dynamically analyze the long-term utility of the recommendation method. However, these two aspects can be studied by the dynamical method, which essentially investigates the intrinsic evolution mechanism of things, and is widely used to study a variety of actual problems. So, in this paper, network dynamics is used to study the recommendation on the user-movie network, which consists of users and movies, and the movies are watched either by the personal search or through the recommendation. Firstly, dynamical models are established to characterize the personal search and the system recommendation mechanism: the personal search model, the random recommendation model, the preference recommendation model, the degree recommendation model and the hybrid recommendation model. The rationality of the models established is verified by comparing the stochastic simulation with the numerical simulation. Moreover, the validity of the recommendation methods is evaluated by studying the movie degree, which is defined as the number of the movie that has been watched. Finally, we combine the personal search and the recommendation to establish a more general model. The change of the average degree of all the movies is given with the strength of the recommendation. Results show that for each recommendation method, the change of the movie degree is different, and is related to the initial degree of movies, the adjacency matrix A representing the relation between users and movies, the time t. Additionally, we find that in a long time, the degree recommendation is not as good as that in a short time, which fully demonstrates the advantage of the dynamical method. For the whole user-movie system, the preference recommendation is the best.

  12. The influence of social networking technologies on female religious veil-wearing behavior in Iran.

    Science.gov (United States)

    Young, Sean D; Shakiba, Abbas; Kwok, Justin; Montazeri, Mohammad Sadegh

    2014-05-01

    Abstract Social networking technologies can influence attitudes, behaviors, and social norms. Research on this topic has been conducted primarily among early adopters of technology and within the United States. However, it is important to evaluate how social media might affect people's behaviors in international settings, especially among countries with longstanding, government recommended, cultural and religious traditions and behaviors, such as Iran. This study seeks to assess whether Iranian women who have been using social networking technologies for a longer time (compared to those who have recently joined) would be less likely to cover themselves with a veil and be more comfortable publicly displaying pictures of this behavior on Facebook. Iranian females (N=253) were selected through snowball sampling from nongovernmental organizations in November 2011 and asked to complete a survey assessing their use of Facebook, concerns about not wearing a veil in Facebook pictures, and their actual likelihood of wearing a veil. Items were combined to measure lack of interest in wearing a veil. Length of time as a Facebook user was significantly associated with not wearing a veil (b=0.16, pSocial networking technologies can affect attitudes and behaviors internationally. We discuss methods of using social media for self-presentation and expression, as well as the difficulties (and importance) of studying use of technologies, such as social media, internationally.

  13. Efficient technologies or user behaviour, which is the more important when reducing households' energy consumption?

    DEFF Research Database (Denmark)

    Gram-Hanssen, Kirsten

    2013-01-01

    , both for understanding why some households consume much more energy than others, and when looking for relevant approaches to a future low-carbon society. The paper uses several sources to explore this question, most of them from a Danish context, including results from the researcher's own projects......Much policy effort focuses on energy efficiency of technology, though not only efficiency but also user behaviour is an important factor influencing the amount of consumed energy. This paper explores to what extent energy efficiency of appliances and houses or user behaviour is the more important...... in Denmark. In the conclusion, these results are discussed in a broader international perspective and it is concluded that more research in this field is necessary. In relation to energy policy, it is argued that it is not a question of technology efficiency or behaviour, as both have to be included...

  14. Ensuring Energy Efficient 5G User Equipment by Technology Evolution and Reuse

    DEFF Research Database (Denmark)

    Lauridsen, Mads; Berardinelli, Gilberto; Sørensen, Troels Bundgaard

    2014-01-01

    the features’ pros and cons in achieving high performance in terms of data rate and/or latency while limiting their effect on the UE power consumption. Based on the discussion we give general recommendations for an energy efficient 5G design in the context of a previously proposed RAT concept.......Research on fifth generation (5G) radio access technology (RAT) is ramping up, with the goal of significantly improving user data rates and latency compared to previous radio generations. While energy efficiency (EE) of the user equipment (UE) was not a key optimization parameter for the current...... standards, it is anticipated to become a distinguishing factor for 5G. In this paper, we analyze established and emerging technological solutions for features such as waveform, frame structure, duplexing and multiple antenna transmission from an EE perspective. Our contribution is to identify and discuss...

  15. Aligning product development and user perspectives: social-behavioural dimensions of multipurpose prevention technologies.

    Science.gov (United States)

    Brady, M; Tolley, E

    2014-10-01

    Multipurpose prevention technologies provide a compelling response to the multiple and reinforcing sexual and reproductive health risks faced by women globally. To ensure that this potential is realised, product-specific characteristics and their social-behavioural correlates must be considered early in the product development process. This paper provides an overview of the key user-related social and behavioural dimensions of three broad categories of multipurpose prevention technologies: 1) sustained release vaginal rings, 2) pericoital vaginal products, and 3) co-formulated or co-administered injectables. The authors build upon the broad parameters of Target Product Profiles for such products, aligning them with user perspective considerations. © 2014 Royal College of Obstetricians and Gynaecologists.

  16. Towards the systematic development of medical networking technology.

    Science.gov (United States)

    Faust, Oliver; Shetty, Ravindra; Sree, S Vinitha; Acharya, Sripathi; Acharya U, Rajendra; Ng, E Y K; Poo, Chua Kok; Suri, Jasjit

    2011-12-01

    Currently, there is a disparity in the availability of doctors between urban and rural areas of developing countries. Most experienced doctors and specialists, as well as advanced diagnostic technologies, are available in urban areas. People living in rural areas have less or sometimes even no access to affordable healthcare facilities. Increasing the number of doctors and charitable medical hospitals or deploying advanced medical technologies in these areas might not be economically feasible, especially in developing countries. We need to mobilize science and technology to master this complex, large scale problem in an objective, logical, and professional way. This can only be achieved with a collaborative effort where a team of experts works on both technical and non-technical aspects of this health care divide. In this paper we use a systems engineering framework to discuss hospital networks which might be solution for the problem. We argue that with the advancement in communication and networking technologies, economically middle class people and even some rural poor have access to internet and mobile communication systems. Thus, Hospital Digital Networking Technologies (HDNT), such as telemedicine, can be developed to utilize internet, mobile and satellite communication systems to connect primitive rural healthcare centers to well advanced modern urban setups and thereby provide better consultation and diagnostic care to the needy people. This paper describes requirements and limitations of the HDNTs. It also presents the features of telemedicine, the implementation issues and the application of wireless technologies in the field of medical networking.

  17. MONITORING POTENTIAL DRUG INTERACTIONS AND REACTIONS VIA NETWORK ANALYSIS OF INSTAGRAM USER TIMELINES

    Science.gov (United States)

    CORREIA, RION BRATTIG; LI, LANG; ROCHA, LUIS M.

    2015-01-01

    Much recent research aims to identify evidence for Drug-Drug Interactions (DDI) and Adverse Drug reactions (ADR) from the biomedical scientific literature. In addition to this “Bibliome”, the universe of social media provides a very promising source of large-scale data that can help identify DDI and ADR in ways that have not been hitherto possible. Given the large number of users, analysis of social media data may be useful to identify under-reported, population-level pathology associated with DDI, thus further contributing to improvements in population health. Moreover, tapping into this data allows us to infer drug interactions with natural products—including cannabis—which constitute an array of DDI very poorly explored by biomedical research thus far. Our goal is to determine the potential of Instagram for public health monitoring and surveillance for DDI, ADR, and behavioral pathology at large. Most social media analysis focuses on Twitter and Facebook, but Instagram is an increasingly important platform, especially among teens, with unrestricted access of public posts, high availability of posts with geolocation coordinates, and images to supplement textual analysis. Using drug, symptom, and natural product dictionaries for identification of the various types of DDI and ADR evidence, we have collected close to 7000 user timelines spanning from October 2010 to June 2015. We report on 1) the development of a monitoring tool to easily observe user-level timelines associated with drug and symptom terms of interest, and 2) population-level behavior via the analysis of co-occurrence networks computed from user timelines at three different scales: monthly, weekly, and daily occurrences. Analysis of these networks further reveals 3) drug and symptom direct and indirect associations with greater support in user timelines, as well as 4) clusters of symptoms and drugs revealed by the collective behavior of the observed population. This demonstrates that

  18. MONITORING POTENTIAL DRUG INTERACTIONS AND REACTIONS VIA NETWORK ANALYSIS OF INSTAGRAM USER TIMELINES.

    Science.gov (United States)

    Correia, Rion Brattig; Li, Lang; Rocha, Luis M

    2016-01-01

    Much recent research aims to identify evidence for Drug-Drug Interactions (DDI) and Adverse Drug reactions (ADR) from the biomedical scientific literature. In addition to this "Bibliome", the universe of social media provides a very promising source of large-scale data that can help identify DDI and ADR in ways that have not been hitherto possible. Given the large number of users, analysis of social media data may be useful to identify under-reported, population-level pathology associated with DDI, thus further contributing to improvements in population health. Moreover, tapping into this data allows us to infer drug interactions with natural products-including cannabis-which constitute an array of DDI very poorly explored by biomedical research thus far. Our goal is to determine the potential of Instagram for public health monitoring and surveillance for DDI, ADR, and behavioral pathology at large. Most social media analysis focuses on Twitter and Facebook, but Instagram is an increasingly important platform, especially among teens, with unrestricted access of public posts, high availability of posts with geolocation coordinates, and images to supplement textual analysis. Using drug, symptom, and natural product dictionaries for identification of the various types of DDI and ADR evidence, we have collected close to 7000 user timelines spanning from October 2010 to June 2015.We report on 1) the development of a monitoring tool to easily observe user-level timelines associated with drug and symptom terms of interest, and 2) population-level behavior via the analysis of co-occurrence networks computed from user timelines at three different scales: monthly, weekly, and daily occurrences. Analysis of these networks further reveals 3) drug and symptom direct and indirect associations with greater support in user timelines, as well as 4) clusters of symptoms and drugs revealed by the collective behavior of the observed population. This demonstrates that Instagram

  19. Meeting End User Needs in Collaborative Medical Device Technology Development Research Projects: A Qualitative Case Study.

    Science.gov (United States)

    Strisland, Frode; Svagård, Ingrid Storruste; Austad, Hanne Opsahl; Reitan, Jarl

    2017-01-01

    The aim of this case study has been to investigate to what extent user centered design (UCD) methodologies have been applied, how the process and outcomes were perceived by project team members, and what were potential barriers towards meeting end user needs. The case studied was the European Union Framework 7 integrated project d-LIVER (2011-2015), which aimed at developing an integrated care system for chronic liver disease patient management. d-LIVER is an example of a public funded, international, multidisciplinary, collaborative research project where development starts from a low technology readiness level, but where research is motivated by societal needs for better health care solutions. Awareness of central end user needs are therefore crucial. 14 project participants were interviewed. To meet societal and end user needs represent a prominent motivation factor for participants. The project organization with only clinical partners interacting with end users was accepted as a fact of life and not as a project pain point. A summary of observations and recommendations for good practice is given.

  20. Technological Factors, User Characteristics and Didactic Strategies in Educational Virtual Environments

    DEFF Research Database (Denmark)

    Natsis, Antonios; Vrellis, Ioannis; Papachristos, Nikiforos

    2012-01-01

    Technological factors, user characteristics and didactic strategies do not function consistently across Educational Virtual Environments. This study investigates the impact of viewing condition and didactic strategy on attention allocation, suspension of disbelief, spatial presence, and learning...... outcomes in an Educational Virtual Environment concerning ancient Greek pottery. Our results show that the viewing condition does not affect attention allocation, suspension of disbelief, and spatial presence. Learning outcomes are better in the monoscopic viewing condition. Didactic strategy has an impact...... Virtual Environments....

  1. Technology Licensing Strategy for Network Product in a Service Industry

    Directory of Open Access Journals (Sweden)

    Xianpei Hong

    2015-01-01

    Full Text Available Technology licensing has gained significant attention in literature and practice as a rapid and effective way to improve firm’s capability of technology innovation. In this paper, we investigate a duopolistic service provider competition market, where service providers develop and sell a kind of network product. In this setting, we analyze the innovating service provider’s four licensing strategies: no licensing, fixed fee licensing, royalty licensing, and two-part tariff licensing. The literature suggests that when the network products can be completely substituted, two-part tariff licensing is the optimal strategy of the innovating service provider. We find that when the network products cannot be completely substituted, two-part tariff licensing is not always optimal. The degree of the product differentiation, the intensity of the network effects, and the R&D cost of the potential licensee play a key role in determining the innovating service provider’s optimal licensing strategies.

  2. Experience with technology dynamics of user experience with mobile media devices

    CERN Document Server

    al-Azzawi, Ali

    2013-01-01

    With a focus on gaining an empirically derived understanding of the underlying psychological dimensions and processes behind people’s experiences with technology, this book contributes to the debate of user experience (UX) within several disciplines, including HCI, design and marketing. It analyses UX dynamics at various time scales, and explores the very nature of time and meaning in the context of UX.Experience with Technology uses personal construct theory (PCT) as a theoretical and methodological starting point to this project. Major case-studies are described that examine people’s exp

  3. Security analysis and enhanced user authentication in proxy mobile IPv6 networks.

    Science.gov (United States)

    Kang, Dongwoo; Jung, Jaewook; Lee, Donghoon; Kim, Hyoungshick; Won, Dongho

    2017-01-01

    The Proxy Mobile IPv6 (PMIPv6) is a network-based mobility management protocol that allows a Mobile Node(MN) connected to the PMIPv6 domain to move from one network to another without changing the assigned IPv6 address. The user authentication procedure in this protocol is not standardized, but many smartcard based authentication schemes have been proposed. Recently, Alizadeh et al. proposed an authentication scheme for the PMIPv6. However, it could allow an attacker to derive an encryption key that must be securely shared between MN and the Mobile Access Gate(MAG). As a result, outsider adversary can derive MN's identity, password and session key. In this paper, we analyze Alizadeh et al.'s scheme regarding security and propose an enhanced authentication scheme that uses a dynamic identity to satisfy anonymity. Furthermore, we use BAN logic to show that our scheme can successfully generate and communicate with the inter-entity session key.

  4. Security analysis and enhanced user authentication in proxy mobile IPv6 networks.

    Directory of Open Access Journals (Sweden)

    Dongwoo Kang

    Full Text Available The Proxy Mobile IPv6 (PMIPv6 is a network-based mobility management protocol that allows a Mobile Node(MN connected to the PMIPv6 domain to move from one network to another without changing the assigned IPv6 address. The user authentication procedure in this protocol is not standardized, but many smartcard based authentication schemes have been proposed. Recently, Alizadeh et al. proposed an authentication scheme for the PMIPv6. However, it could allow an attacker to derive an encryption key that must be securely shared between MN and the Mobile Access Gate(MAG. As a result, outsider adversary can derive MN's identity, password and session key. In this paper, we analyze Alizadeh et al.'s scheme regarding security and propose an enhanced authentication scheme that uses a dynamic identity to satisfy anonymity. Furthermore, we use BAN logic to show that our scheme can successfully generate and communicate with the inter-entity session key.

  5. TROVE: A User-friendly Tool for Visualizing and Analyzing Cancer Hallmarks in Signaling Networks.

    Science.gov (United States)

    Chua, Huey Eng; Bhowmick, Sourav S; Zheng, Jie

    2017-09-22

    Cancer hallmarks, a concept that seeks to explain the complexity of cancer initiation and development, provide a new perspective of studying cancer signaling which could lead to a greater understanding of this complex disease. However, to the best of our knowledge, there is currently a lack of tools that support such hallmark-based study of the cancer signaling network, thereby impeding the gain of knowledge in this area. We present TROVE, a user-friendly software that facilitates hallmark annotation, visualization and analysis in cancer signaling networks. In particular, TROVE facilitates hallmark analysis specific to particular cancer types. Available under the Eclipse Public License from: https://sites.google.com/site/cosbyntu/softwares/trove and https://github.com/trove2017/Trove. hechua@ntu.edu.sg or assourav@ntu.edu.sg. © The Author (2017). Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com

  6. A Review of User-Centered Design for Diabetes-Related Consumer Health Informatics Technologies

    Science.gov (United States)

    LeRouge, Cynthia; Wickramasinghe, Nilmini

    2013-01-01

    User-centered design (UCD) is well recognized as an effective human factor engineering strategy for designing ease of use in the total customer experience with products and information technology that has been applied specifically to health care information technology systems. We conducted a literature review to analyze the current research regarding the use of UCD methods and principles to support the development or evaluation of diabetes-related consumer health informatics technology (CHIT) initiatives. Findings indicate that (1) UCD activities have been applied across the technology development life cycle stages, (2) there are benefits to incorporating UCD to better inform CHIT development in this area, and (3) the degree of adoption of the UCD process is quite uneven across diabetes CHIT studies. In addition, few to no studies report on methods used across all phases of the life cycle with process detail. To address that void, the Appendix provides an illustrative case study example of UCD techniques across development stages. PMID:23911188

  7. Empowering users through design interdisciplinary studies and combined approaches for technological products and services

    CERN Document Server

    2015-01-01

    At the crossroads of various disciplines, this collective work examines the possibility of a new end-user “engagement” in ongoing digital/technological products and services development. It provides an overview of recent research specifically focused on the user’s democratic participation and empowerment. It also enables readers to better identify the main opportunities of participatory design, a concept which encourages the blurring of the role between user and designer. This allows people to escape their status as “end-user” and to elevate themselves to the level of creator. This book explores new avenues for rethinking the processes and practices of corporate innovation in order to cope with current socio-economic and technological changes. In so doing, it aims to help companies renew industrial models that allow them to design and produce new ranges of technological products and services by giving the user an active role in the development process, far beyond the basic role of consumer. Intended...

  8. Cognitive wireless networks using the CSS technology

    CERN Document Server

    Li, Meiling; Pan, Jeng-Shyang

    2016-01-01

    The aim of this book is to provide some useful methods to improve the spectrum sensing performance in a systematic way, and point out an effective method for the application of cognitive radio technology in wireless communications. The book gives a state-of-the-art survey and proposes some new cooperative spectrum sensing (CSS) methods attempting to achieve better performance. For each CSS, the main idea and corresponding algorithm design are elaborated in detail. This book covers the fundamental concepts and the core technologies of CSS, especially its latest developments. Each chapter is presented in a self-sufficient and independent way so that the reader can select the chapters interesting to them. The methodologies are described in detail so that the readers can repeat the corresponding experiments easily. It will be a useful book for researchers helping them to understand the classifications of CSS, inspiring new ideas about the novel CSS technology for CR, and learning new ideas from the current status...

  9. User involvement in service delivery predicts outcomes of assistive technology use: A cross-sectional study in Bangladesh

    Directory of Open Access Journals (Sweden)

    Borg Johan

    2012-09-01

    Full Text Available Abstract Background Knowledge about the relation between user involvement in the provision of assistive technology and outcomes of assistive technology use is a prerequisite for the development of efficient service delivery strategies. However, current knowledge is limited, particularly from low-income countries where affordability is an issue. The objective was therefore to explore the relation between outcomes of assistive technology use and user involvement in the service delivery process in Bangladesh. Methods Using structured interviews, data from 136 users of hearing aids and 149 users of manual wheelchairs were collected. Outcomes were measured using the International Outcome Inventory for Hearing Aids (IOI-HA, which was adapted for wheelchair users. Predictors of user involvement included preference, measurement and training. Results Users reported outcomes comparable to those found in other high- and low-income countries. User involvement increased the likelihood for reporting better outcomes except for measurement among hearing aid users. Conclusions The findings support the provision of assistive technology as a strategy to improve the participation of people with disabilities in society. They also support current policies and guidelines for user-involvement in the service delivery process. Simplified strategies for provision of hearing aids may be explored.

  10. Older adults' perspectives on the process of becoming users of assistive technology: a qualitative systematic review and meta-synthesis.

    Science.gov (United States)

    Larsen, Stina Meyer; Mortensen, Rikke Falgreen; Kristensen, Hanne Kaae; Hounsgaard, Lise

    2018-04-22

    To identify, synthesize, and evaluate existing literature concerning the process of becoming a user of assistive technology (AT). A systematic review and meta-synthesis were carried out. Five bibliographic databases (MEDLINE via PubMed, CINAHL, Web of Science, PsycINFO and SocINDEX) were systematically searched up to 13 th of March 2017, using two sets of search terms: (i) elderly and synonyms and (ii) assistive technology and similar words, and combined with a qualitative research filter. Articles were screened, read and critically assessed. The meta-synthesis was guided by Ricoeur's theory of interpretation. Seventeen out of 4645 articles were included. Five phases emerged relating to the process of becoming a user of AT: phase A: Evaluating need, phase B: Acknowledging need, phase C: Incorporating the AT into daily life, phase D: Using the AT, and phase E: Future use. Three transitions, describing factors essential to moving from one phase to the next, were identified; from phase A-B: Valued activities are threatened, from phase B-C: Obtaining the AT and from phase C-D: Trust in the AT. No transition was identified from phase D-E. The meta-synthesis led to a deeper understanding of the process of older adults becoming users of AT, by exploring findings across the included articles. The identified phases and transitions in the systematic review serve as an analytical framework for understanding the process from the older adult's perspective. This review advocates for using a client-centred approach throughout the entire delivery process. Implications for rehabilitation The process of the older adult becoming a user of AT involves an individualized time factor, and this supports the practice of individualized follow-up. The process of becoming a user of AT is closely related to self-image; healthcare professionals should support not only the use of AT but also the older adult's emotional adjustment to a new self-image. The process is highly influenced by the older

  11. Unanticipated Effect of a Randomized Peer Network Intervention on Depressive Symptoms among Young Methamphetamine Users in Thailand

    Science.gov (United States)

    German, D.; Sutcliffe, C. G.; Sirirojn, B.; Sherman, S. G.; Latkin, C. A.; Aramrattana, A.; Celentano, D. D.

    2012-01-01

    We examined the effect on depressive symptoms of a peer network-oriented intervention effective in reducing sexual risk behavior and methamphetamine (MA) use. Current Thai MA users aged 18-25 years and their drug and/or sex network members enrolled in a randomized controlled trial with 4 follow-ups over 12 months. A total of 415 index participants…

  12. Router Agent Technology for Policy-Based Network Management

    Science.gov (United States)

    Chow, Edward T.; Sudhir, Gurusham; Chang, Hsin-Ping; James, Mark; Liu, Yih-Chiao J.; Chiang, Winston

    2011-01-01

    This innovation can be run as a standalone network application on any computer in a networked environment. This design can be configured to control one or more routers (one instance per router), and can also be configured to listen to a policy server over the network to receive new policies based on the policy- based network management technology. The Router Agent Technology transforms the received policies into suitable Access Control List syntax for the routers it is configured to control. It commits the newly generated access control lists to the routers and provides feedback regarding any errors that were faced. The innovation also automatically generates a time-stamped log file regarding all updates to the router it is configured to control. This technology, once installed on a local network computer and started, is autonomous because it has the capability to keep listening to new policies from the policy server, transforming those policies to router-compliant access lists, and committing those access lists to a specified interface on the specified router on the network with any error feedback regarding commitment process. The stand-alone application is named RouterAgent and is currently realized as a fully functional (version 1) implementation for the Windows operating system and for CISCO routers.

  13. Building technology transfer meetings: A collaborative model for transferring DOE research results to potential users

    Energy Technology Data Exchange (ETDEWEB)

    Shankle, D.L.; Hawkins, D.M. [Pacific Northwest Lab., Richland, WA (United States); Love, P.M. [Oak Ridge National Lab., TN (United States); Wilde, G.M. [Lawrence Berkeley Lab., CA (United States)

    1994-08-01

    Transferring the technology and results from U.S. Department of Energy (DOE)-sponsored building energy research to potential users is a critical part of DOE`s successful research programs. To assist in this transfer of information and technologies, the DOE Office of Building Technologies (OBT) has established Building Technology Transfer Meetings that are held twice each year at one of the 10 DOE Regional Support Offices. Meeting participants include DOE personnel and representatives from each of the national laboratories involved in OBT buildings energy research as well as representatives from the DOE Regional Support Offices and other agencies involved in the buildings sector. Since 1991, OBT has held five meetings: Washington D.C., San Francisco, Denver, Oak Ridge, and Seattle. The purpose of these meetings is twofold: (1) for DOE to share information about such topics as new research results, new technologies, and new ways to collaborate with industry and universities to leverage resources; and (2) for the participants to use this information within their region to accelerate the transfer and deployment of new energy-efficient building technologies. The meetings include presentations, demonstrations, and tours. The meetings have provided an excellent opportunity for staff from the Regional Support Offices to learn about new technologies through their interactions with OBT and national laboratory program managers. Meeting tours and demonstrations have provided beneficial opportunities to get hands-on experience with new technologies and to see them in practice.

  14. MUPBED - interworking challenges in a multi-domain and multi-technology network environment

    DEFF Research Database (Denmark)

    Foisel, Hans-Martin; Spaeth, Jan; Cavazzoni, Carlo

    2007-01-01

    Todays data transport networks are evolving continuously towards customer oriented and application aware networks. This evolution happens in Europe in a highly diverse network environment, covering multiple network domains, layers, technologies, control and management approaches. In this paper...

  15. Bridging the Gap from Networking Technologies to Applications: Workshop Report

    Science.gov (United States)

    Johnson, Marjory J.; desJardins, Richard

    2000-01-01

    The objective of the Next Generation Internet (NGI) Federal program is threefold, encompassing development of networking technologies, high-performance network testbeds, and revolutionary applications. There have been notable advances in emerging network technologies and several nationwide testbeds have been established, but the integration of emerging technologies into applications is lagging. To help bridge this gap between developers of NGI networking technologies and developers of NGI applications, the NASA Research and Education Network (NREN) project hosted a two-day workshop at NASA Ames Research Center in August 1999. This paper presents a summary of the results of this workshop and also describes some of the challenges NREN is facing while incorporating new technologies into HPCC and other NASA applications. The workshop focused on three technologies - Quality of Service (QoS), advanced multicast, and security-and five major NGI application areas - telemedicine, digital earth, digital video, distributed data-intensive applications, and computational infrastructure applications. Network technology experts, application developers, and NGI testbed representatives came together at the workshop to promote cross-fertilization between the groups. Presentations on the first day, including an overview of the three technologies, application case studies and testbed status reports, laid the foundation for discussions on the second day. The objective of these latter discussions, held within smaller breakout groups, was to establish a coherent picture of the current status of the various pieces of each of the three technologies, to create a roadmap outlining future technology development, and to offer technological guidance to application developers. In this paper we first present a brief overview of the NGI applications that were represented at the workshop, focusing on the identification of technological advances that have successfully been incorporated in each

  16. Hybrid Fiber Radio Networks: New concepts and technologies

    OpenAIRE

    Torres Román, Rosa C.

    2010-01-01

    To study the main trends which drive the merging of fiber and wireless technologies in access networks. As the hybrid radio networks constitute a new and emerging field of knowledge it is difficult to get a clear picture of their main building blocks and basic technologies and concepts. Due to the lack of reference texts with a basic entry level, in this PFC we aim at carrying out a thorough study of the related literature in order to establish a clear classification of systems and techniques...

  17. Applying New Network Security Technologies to SCADA Systems.

    Energy Technology Data Exchange (ETDEWEB)

    Hurd, Steven A; Stamp, Jason Edwin; Duggan, David P; Chavez, Adrian R.

    2006-11-01

    Supervisory Control and Data Acquisition (SCADA) systems for automation are very important for critical infrastructure and manufacturing operations. They have been implemented to work in a number of physical environments using a variety of hardware, software, networking protocols, and communications technologies, often before security issues became of paramount concern. To offer solutions to security shortcomings in the short/medium term, this project was to identify technologies used to secure "traditional" IT networks and systems, and then assess their efficacy with respect to SCADA systems. These proposed solutions must be relatively simple to implement, reliable, and acceptable to SCADA owners and operators. 4This page intentionally left blank.

  18. Do social networks and technological capabilities help knowledge management?

    Directory of Open Access Journals (Sweden)

    Encarnación García-Sánchez

    2017-12-01

    Full Text Available Dynamic capabilities are currently becoming an important extension of the theory of resources and capabilities that enables companies to adapt better in the current competitive environment. This paper examines how knowledge management, a dynamic function related to management or administration of a set of knowledge flows, develops thanks to the greater dynamism of social networks. It then shows how this relationship is especially strengthened by different technological capabilities. To achieve these goals, the paper examines the main tools that permit companies to develop an ability to achieve competitive advantage relative to the technological capabilities of managers and workers, social networks and knowledge management.

  19. Control of coupled oscillator networks with application to microgrid technologies

    Science.gov (United States)

    Skardal, Per Sebastian; Arenas, Alex

    2015-01-01

    The control of complex systems and network-coupled dynamical systems is a topic of vital theoretical importance in mathematics and physics with a wide range of applications in engineering and various other sciences. Motivated by recent research into smart grid technologies, we study the control of synchronization and consider the important case of networks of coupled phase oscillators with nonlinear interactions—a paradigmatic example that has guided our understanding of self-organization for decades. We develop a method for control based on identifying and stabilizing problematic oscillators, resulting in a stable spectrum of eigenvalues, and in turn a linearly stable synchronized state. The amount of control, that is, number of oscillators, required to stabilize the network is primarily dictated by the coupling strength, dynamical heterogeneity, and mean degree of the network, and depends little on the structural heterogeneity of the network itself. PMID:26601231

  20. Control of coupled oscillator networks with application to microgrid technologies

    Science.gov (United States)

    Arenas, Alex

    The control of complex systems and network-coupled dynamical systems is a topic of vital theoretical importance in mathematics and physics with a wide range of applications in engineering and various other sciences. Motivated by recent research into smart grid technologies, we study the control of synchronization and consider the important case of networks of coupled phase oscillators with nonlinear interactions-a paradigmatic example that has guided our understanding of self-organization for decades. We develop a method for control based on identifying and stabilizing problematic oscillators, resulting in a stable spectrum of eigenvalues, and in turn a linearly stable syn- chronized state. The amount of control, that is, number of oscillators, required to stabilize the network is primarily dictated by the coupling strength, dynamical heterogeneity, and mean degree of the network, and depends little on the structural heterogeneity of the network itself.

  1. Developing and articulating intersectorial networks for integral care of drug users in vulnerable contexts

    Directory of Open Access Journals (Sweden)

    Maria de Nazareth Rodrigues Malcher de Oliveira Silva

    2014-08-01

    Full Text Available This manuscript presents an experience report with some activities that the Reference Center on Drugs and Associated Vulnerabilities - CRR, ‘Faculdade Ceilândia’/University of Brasilia - UNB implemented and developed in 2013. This account allows us to reflect on the process of building partnerships based on social networks and the notion of territory for people with problems related to drugs and their associated vulnerability. The experience follows the current national framework, in which the social network has become a central paradigm of public practices and policies (e.g. Law 10.216/2001. These changes occur in the model of care for people with mental disorders, including the integral health policy for users and dependents of alcohol and other drugs. The CRR team mapped local social networks, i.e. several public institutions in different sectors, in four municipalities: one in the Federal District (Brazlândia and three in the state of Goiás (Valparaiso, Luziânia, Águas Lindas. After the mapping, the CRR team sought to articulate and establish an agenda to discuss alcohol and drug use and its associated vulnerabilities among these different institutions, sectors and professionals, e.g. nurses, physicians, occupational therapists, social workers, and police officers. This strategy enabled several actors to develop and qualify their local intersectorial network, which consequently qualifies the integral care actions, as recommended by several national policies.

  2. 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.

  3. 75 FR 55360 - Networking and Information Technology Research and Development (NITRD) Program: Draft NITRD 2010...

    Science.gov (United States)

    2010-09-10

    ... NATIONAL SCIENCE FOUNDATION Networking and Information Technology Research and Development (NITRD... Information Technology Research and Development (NITRD). ACTION: Notice, request for public comment. FOR..., the National Coordination Office for Networking and Information Technology Research and Development...

  4. Internet and social network users' profiles in Renal Transplant Recipients in France.

    Science.gov (United States)

    Mouelhi, Yosra; Alessandrini, Marine; Pauly, Vanessa; Dussol, Bertrand; Gentile, Stéphanie

    2017-08-03

    The use of the Internet for searching and sharing health information and for health care interactions may have a great potential for Renal Transplant Recipients (RTR). This study aims to determine the characteristics associated with Internet and social network use in a representative sample of RTR at the time of their inclusion in the study. Data of this cross-sectional design is retrieved from a longitudinal study conducted in five French kidney transplant centers in 2011, and included Renal Transplant Recipients aged 18 years with a functioning graft for at least 1 year. Measures include demographic characteristics (age, gender, level of education, employment status, living arrangement, having children, invalidity and monthly incomes in the household), psycho-social characteristics measured by the perceived social support questionnaire, and medical characteristics (previous dialysis treatment, duration since transplantation, graft rejection episodes, chronic graft dysfunction, health status and comorbidities: neoplasia for the current transplant, hypertension, diabetes mellitus, smoking status, BMI > 30 kg/m 2 and Charlson Comorbidity Index (CCI)). Polytomous linear regression analysis was performed to describe the Internet and social network users' profiles, using lack of Internet access as the comparison category. Among the 1416 RTR participating in the study, 20.1% had no Internet access in the household, 29.4% connected to social networks and 50.5% were not connected to social networks. Patients who connected the most to the Internet and social networks were younger, male, without children, employed, with high monthly incomes in the household, without hypertension and having felt a need for an informative or an esteem support. In our study, the majority of RTR were actively using Internet and social networks. Renal transplant units should develop flexible and Web-based sources related to transplant information, which will allow a rapid adaptation to

  5. Disruptive Technologies and Networking in Telecom Industries

    DEFF Research Database (Denmark)

    Madsen, Erik Strøjer; Hartington, Simon Preuthun

    2015-01-01

    This article discuss’ how economics of scale in supply and demand in the telecommunication industry has developed and how this has had great effect on the widespread usage and popularity of smartphones. By using this as a theoretical ground the paper looks into technical innovation...... in the telecommunication industry and finds significant similarities between the industry development and the literature on disruptive technology, which finds that incumbent companies are not able to react in a successful way when disruptions occur in their industry. By studying how the telecommunication industry...

  6. Disruptive technologies and networking in telecom industries

    DEFF Research Database (Denmark)

    Madsen, Erik Strøjer; Hartington, Simon

    This article discuss’ how economics of scale in supply and demand in the telecommunication industry has developed and how this has had great effect on the widespread usage and popularity of smart phones. By using this as a theoretical ground the paper looks into technical innovation...... in the telecommunication industry and finds significant similarities between the industry development and the literature on disruptive technology, which finds that incumbent companies are not able to react in a successful way when disruptions occur in their industry. By studying how the telecommunication industry...

  7. A novel MLP network implementation in CMOL technology

    Directory of Open Access Journals (Sweden)

    Abdalhossein Rezai

    2014-09-01

    Full Text Available Hybrid CMOS/nanodevice technology is a well-known candidate to extend the exponential Moor-Law progress of microelectronics beyond the 10-nm frontier. This paper presents and evaluates a novel method for synaptic weights implementation of artificial neural networks in CMOL technology, a hybrid CMOS/nanodevice technology. In this novel method, the analog property of the I–V characteristic of the nanodevice is utilized to implement each neuromorphic synaptic weight. Each synaptic weight is also implemented by using one nanodevice instead of several nanodevices. Moreover, the proposed method is applied to the multilayer perceptron (MLP network in CMOL technology. Our analysis shows that the power consumption and speed are effectively improved in the proposed method compared to other methods at the expense of a reasonable overhead defect tolerance.

  8. Performance Analysis and Optimization for Cognitive Radio Networks with Classified Secondary Users and Impatient Packets

    Directory of Open Access Journals (Sweden)

    Yuan Zhao

    2017-01-01

    Full Text Available A cognitive radio network with classified Secondary Users (SUs is considered. There are two types of SU packets, namely, SU1 packets and SU2 packets, in the system. The SU1 packets have higher priority than the SU2 packets. Considering the diversity of the SU packets and the real-time need of the interrupted SU packets, a novel spectrum allocation strategy with classified SUs and impatient packets is proposed. Based on the number of PU packets, SU1 packets, and SU2 packets in the system, by modeling the queue dynamics of the networks users as a three-dimensional discrete-time Markov chain, the transition probability matrix of the Markov chain is given. Then with the steady-state analysis, some important performance measures of the SU2 packets are derived to show the system performance with numerical results. Specially, in order to optimize the system actions of the SU2 packets, the individually optimal strategy and the socially optimal strategy for the SU2 packets are demonstrated. Finally, a pricing mechanism is provided to oblige the SU2 packets to follow the socially optimal strategy.

  9. Outlier populations: individual and social network correlates of solvent-using injection drug users.

    Directory of Open Access Journals (Sweden)

    Souradet Y Shaw

    Full Text Available We previously identified a high prevalence of Hepatitis C (HCV amongst solvent-using injection drug users (S-IDU relative to other injection drug users within the same locality. Here we incorporated social network variables to better characterize some of the behavioural characteristics that may be putting this specific subgroup of IDU at elevated disease risk.A cross-sectional survey of at-risk populations was carried out in Winnipeg, Canada in 2009. Individuals reporting any history of injection drug and/or solvent use were included in the study. Associations between subgroup membership, infection with HCV and HIV and individual and social network variables were examined.In relation to other IDU, S-IDU were more likely to be infected with HCV, to report ever having shared a syringe, and to associate with other IDU. They were further differentiated in terms of their self-reported sexual orientation, ethnicity and in the injection drugs typically used.Solvent use stands as a proxy measure of numerous other characteristics that put this group of IDU at higher risk of infection. Provision of adequate services to ostracized subpopulations may result in wider population-level benefits.

  10. Mobile user-preference-based data dissemination on mobile P2P networks

    Directory of Open Access Journals (Sweden)

    Kim Dohoon

    2011-01-01

    Full Text Available Abstract A considerable number of studies have been performed recently on mobile peer-to-peer networks (MOPNETs, as the number of services based on mobile devices has increased. However, existing studies still reveal numerous shortcomings, such as bandwidth overhead, and redundant transmission in terms of multi-broadcast between peers. Especially, owing to the characteristics of MOPNETs, it is extremely important to determine broadcast size and to disseminate data within the limited environment of the network. The mechanism directly affects how well resource information in a mobile device is discovered and how data are transmitted. In this context, it is vital to efficiently disseminate data to be able to arrange hierarchal sequences of resource information of each mobile device for better search performance. Especially, it is also vital to determine the broadcast size, considering the consumption patterns of mobile users. In this article, we propose an adaptable algorithm that determines weighted values and disseminates data using the high-order Markov chain (HoMC. We apply weighted values in consideration of the MOPNET environment. In addition, the proposed HoMC-based Mobile User-preference-based Data Dissemination algorithm was simulated with a Qualnet simulator. Results show that the proposed algorithm performs 17.3% better, on average, in terms of data dissemination, than the existing dissemination methods.

  11. [Access and comprehensiveness: the viewpoint of users of a mental health network].

    Science.gov (United States)

    de Oliveira, Raimunda Félix; de Andrade, Luiz Odorico Monteiro; Goya, Neusa

    2012-11-01

    This article analyzes user viewpoints regarding mental health care, with a focus on comprehensiveness and access at Psychosocial Care Centers (PCCs). It is a qualitative study with theoretical and methodological references of the Fourth Generation Evaluation and application of the Hermeneutic Dialectic Circle technique. Twelve users of ten mental health services in Fortaleza were interviewed from March to May 2011. Themes of the study were grouped from the narratives, with the hermeneutics of Paul Ricoeur as the benchmark for analysis. The thematic categories were: viewpoints on mental healthcare; conflicts between supply and the subjective need to receive; similarities and differences: from tutelage to autonomy; absence and belonging: open PCCs and non-community centers; between stigma and humanization. The main findings are: the PCCs are seen as spaces for conviviality able to establish affective and social networks; stigma, prejudice and tutelage are present in the services, in their families and in the community; asylum practices persist in alternative services; the humanization of care extends access and bonding in the services; the trajectory of users of the Unified Health System occurs due to their social and health needs.

  12. Data Mining and Privacy of Social Network Sites' Users: Implications of the Data Mining Problem.

    Science.gov (United States)

    Al-Saggaf, Yeslam; Islam, Md Zahidul

    2015-08-01

    This paper explores the potential of data mining as a technique that could be used by malicious data miners to threaten the privacy of social network sites (SNS) users. It applies a data mining algorithm to a real dataset to provide empirically-based evidence of the ease with which characteristics about the SNS users can be discovered and used in a way that could invade their privacy. One major contribution of this article is the use of the decision forest data mining algorithm (SysFor) to the context of SNS, which does not only build a decision tree but rather a forest allowing the exploration of more logic rules from a dataset. One logic rule that SysFor built in this study, for example, revealed that anyone having a profile picture showing just the face or a picture showing a family is less likely to be lonely. Another contribution of this article is the discussion of the implications of the data mining problem for governments, businesses, developers and the SNS users themselves.

  13. Precoding Design and Power Allocation in Two-User MU-MIMO Wireless Ad Hoc Networks

    Directory of Open Access Journals (Sweden)

    Haole Chen

    2017-10-01

    Full Text Available In this paper, we consider the precoding design and power allocation problem for multi-user multiple-input multiple-output (MU-MIMO wireless ad hoc networks. In the first timeslot, the source node (SN transmits energy and information to a relay node (RN simultaneously within the simultaneous wireless information and power transfer (SWIPT framework. Then, in the second timeslot, based on the decoder and the forwarding (DF protocol, after reassembling the received signal and its own signal, the RN forwards the information to the main user (U1 and simultaneously sends its own information to the secondary user (U2. In this paper, when the transmission rate of the U1 is restricted, the precoding, beamforming, and power splitting (PS transmission ratio are jointly considered to maximize the transmission rate of U2. To maximize the system rate, we design an optimal beamforming matrix and solve the optimization problem by semi-definite relaxation (SDR, considering the high complexity of implementing the optimal solution. Two sub-optimal precoding programs are also discussed: singular value decomposition and block diagonalization. Finally, the performance of the optimization and sub-optimization schemes are compared using a simulation.

  14. Communication and Consumer Activities of Social Networking Sites Users: Cases from Germany, Poland and Russia

    Directory of Open Access Journals (Sweden)

    Malgorzata Bartosik-Purgat

    2017-12-01

    Full Text Available The growth of the Internet heavily influences people’s lives every day, especially by the development of Social Networking Sites (SNS, which since their first appearance have been constantly recording a growing number of users. The main purpose of this paper is to identify the significance of SNS in relation to two activities of individual users: communication and consumer behaviour. The study focuses on the three most popular SNS in three neighbouring countries (Germany, Poland, and Russia namely, FACEBOOK, VKONTAKTE, and YOUTUBE. The methodological approach is twofold: firstly, the authors developed a theoretical background of the areas of using SNS and formulated research questions; secondly, they applied the PAPI and CAWI methods for the data analysis. Regarding the researched activities, it should be noted that SNS users use these platforms more often for communication than consumer actions. The most useful here is FACEBOOK in comparison to YOUTUBE. This study provides results, which can be useful in the management of the enterprises that use SNS for their marketing communication in Germany, Poland, and Russia.

  15. Software-Defined Networks as a Stage of the Network Technology Evolution

    Directory of Open Access Journals (Sweden)

    A. A. Krasotin

    2013-01-01

    Full Text Available The authors of the article focus on the concept of a software defined network. In the beginning, the brief historical account is given concerning software defined networks as a scientific concept, its formation and technological and scientific meaning. The software defined network concept is treated in the article not as the final state-of-the-art in networking, but rather as a possible step and direction in the development of a networking paradigm. The article touches on pros and cons as well of the software defined networking and gives an account of possible stages of development of this technology in the context of other technologies, considering its hybrid with MPLS, as an example. OpenFlow protocol constitutes the main part of the article. The authors further discuss various kinds of existing libraries realizing programmable management routines for a software defined network using OpenFlow. All of these libraries provide API for building modular applications for software defined network management. Touching on practical side of implementation the results of comparative tests of throughput and latency, achieved with these libraries are shown.

  16. Fiber in access technologies and network convergence: an opportunity for optical integration

    Science.gov (United States)

    Ghiggino, Pierpaolo C.

    2008-11-01

    Broadband networks are among the fastest growing segment in telecom. The initial and still very significant push originated with xDSL technologies and indeed a significant amount of research and development is still occurring in this field with impressive results and allowing for a remarkable use of the installed copper infrastructure way beyond its originally planned bandwidth capabilities. However it is clear that ultimately a more suitable fiber based infrastructure will be needed in order to reduce both operational and network technology costs. Such cost reduction in inevitable as the added value to end users is only related to services and these cannot be priced outside a sensible window, whilst the related bandwidth increase is much more dramatic and its huge variability must be met with little or no cost impact by the network and its operation. Fiber in access has indeed the potential to cope with a huge bandwidth demand for many years to come as its inherent bandwidth capabilities are only just tapped by current service requirements. However the whole technology supply chain must follow in line. In particular optical technology must brace itself to cope with the required much larger deployment and greater cost effectiveness, whilst at the same time deliver performance suitable to the bandwidth increase offered in the longer term by the fiber medium. This paper looks at this issues and debates the opportunities for a new class of optical devices making use of the progress in optical integration

  17. Effect of network topology on the spreading of technologies

    International Nuclear Information System (INIS)

    Kocsis, G.; Kun, F.

    2007-01-01

    statistics. We showed that the topology of social contacts of agents plays a significant role in the spreading of telecommunication technologies. To make the model more realistic we considered networks of agents with small-world and scale-free properties. Based on computer simulations we showed that a complex system of a large number of local communities is more favorable for the spreading of technologies than a fully interconnected one

  18. User-centered applications: Use of mobile information technologies to promote sustainable school healthcare services

    Directory of Open Access Journals (Sweden)

    Alida Veldsman

    2015-07-01

    Full Text Available The youth, especially school going children, are the future of any society. It is therefore important that children should receive adequate healthcare support at an early age in order to strive to preserve and ensure better education and welfare of the children and continuity in societal success. Despite the strategic initiatives that aim at improving the general health of school going children, such as South Africa’s Integrated School Health Policy, there still exist challenges in support programmes meant to alleviate the barriers to effective healthcare towards improved education for the school children. Advances in ICT enable a fundamental redesign of healthcare processes based on the use and integration of electronic communication at all levels. New communication technologies can support a transition from institution centric to user-centric applications. This paper defines key principles and challenges for designers, policy makers, and evaluators of user-centred technologies for healthcare in schools. The paper employs the User Experience Management Model (UXM2 to review the current and emerging trends, and highlights challenges related to the design of a typical m-ICT application that supports delivery of healthcare in schools. The paper reaches conclusions for next steps that will advance the domain.

  19. Secure, Mobile, Wireless Network Technology Designed, Developed, and Demonstrated

    Science.gov (United States)

    Ivancic, William D.; Paulsen, Phillip E.

    2004-01-01

    The inability to seamlessly disseminate data securely over a high-integrity, wireless broadband network has been identified as a primary technical barrier to providing an order-of-magnitude increase in aviation capacity and safety. Secure, autonomous communications to and from aircraft will enable advanced, automated, data-intensive air traffic management concepts, increase National Air Space (NAS) capacity, and potentially reduce the overall cost of air travel operations. For the first time ever, secure, mobile, network technology was designed, developed, and demonstrated with state-ofthe- art protocols and applications by a diverse, cooperative Government-industry team led by the NASA Glenn Research Center. This revolutionary technology solution will make fundamentally new airplane system capabilities possible by enabling secure, seamless network connections from platforms in motion (e.g., cars, ships, aircraft, and satellites) to existing terrestrial systems without the need for manual reconfiguration. Called Mobile Router, the new technology autonomously connects and configures networks as they traverse from one operating theater to another. The Mobile Router demonstration aboard the Neah Bay, a U.S. Coast Guard vessel stationed in Cleveland, Ohio, accomplished secure, seamless interoperability of mobile network systems across multiple domains without manual system reconfiguration. The Neah Bay was chosen because of its low cost and communications mission similarity to low-Earth-orbiting satellite platforms. This technology was successfully advanced from technology readiness level (TRL) 2 (concept and/or application formation) to TRL 6 (system model or prototype demonstration in a relevant environment). The secure, seamless interoperability offered by the Mobile Router and encryption device will enable several new, vehicle-specific and systemwide technologies to perform such things as remote, autonomous aircraft performance monitoring and early detection and

  20. Individual and Network Correlates of Antisocial Personality Disorder Among Rural Nonmedical Prescription Opioid Users.

    Science.gov (United States)

    Smith, Rachel V; Young, April M; Mullins, Ursula L; Havens, Jennifer R

    2017-04-01

    Examination of the association of antisocial personality disorder (ASPD) with substance use and HIV risk behaviors within the social networks of rural people who use drugs. Interviewer-administered questionnaires were used to assess substance use, HIV risk behavior, and social network characteristics of drug users (n = 503) living in rural Appalachia. The MINI International Psychiatric Interview was used to determine whether participants met DSM-IV criteria for ASPD and Axis-I psychological comorbidities (eg, major depressive disorder, posttraumatic stress disorder, generalized anxiety disorder). Participants were also tested for herpes simplex 2, hepatitis C, and HIV. Multivariate generalized linear mixed modeling was used to determine the association between ASPD and risk behaviors, substance use, and social network characteristics. Approximately one-third (31%) of participants met DSM-IV criteria for ASPD. In multivariate analysis, distrust and conflict within an individual's social networks, as well as past 30-day use of heroin and crack, male gender, younger age, lesser education, heterosexual orientation, and comorbid MDD were associated with meeting diagnostic criteria for ASPD. Participants meeting criteria for ASPD were more likely to report recent heroin and crack use, which are far less common drugs of abuse in this population in which the predominant drug of abuse is prescription opioids. Greater discord within relationships was also identified among those with ASPD symptomatology. Given the elevated risk for blood-borne infection (eg, HIV) and other negative social and health consequences conferred by this high-risk subgroup, exploration of tailored network-based interventions with mental health assessment is recommended. © 2016 National Rural Health Association.

  1. Lipid Processing Technology: Building a Multilevel Modeling Network

    DEFF Research Database (Denmark)

    Díaz Tovar, Carlos Axel; Mustaffa, Azizul Azri; Mukkerikar, Amol

    2011-01-01

    The aim of this work is to present the development of a computer aided multilevel modeling network for the systematic design and analysis of processes employing lipid technologies. This is achieved by decomposing the problem into four levels of modeling: i) pure component property modeling...

  2. Using Action Research to Investigate Social Networking Technologies

    Science.gov (United States)

    Worrall, Lisa; Harris, Katy

    2013-01-01

    This article outlines the first cycle of an Action Research (AR) investigation into why professional learners are not using the Social Networking Technologies (SNTs) of their bespoke website. It presents the rationale of how this study came about, the ontological and epistemological stance of the authors and how this led to the particular choice…

  3. Strategic Management of Technology and the Structuring of Industrial Networks

    DEFF Research Database (Denmark)

    Sørensen, Ole H.

    The thesis explores the following question: 'How do actants in industrial companies partake in the enactment of locally embedded and globally reaching industrial networks through participation in technology development activities?' It draws on Actor Netwok Theories and analyses three case stories...

  4. Projekt "Baltenet - The Baltic Technology Network" / Leonid Pai

    Index Scriptorium Estoniae

    Pai, Leonid

    2005-01-01

    Baltenet - The Baltic Technology Network on projekt, mille alusel teevad koostööd tehniliste erialade koolituse arendamiseks Baltimere äärsetes riikides neli kutseõppeasutust Soomest, Rootsist, Lätis ja Eestist. Projekti rahastab Euroopa Liidu Leonardo da Vinci programm

  5. TECHNOLOGY TRANSFER NETWORKS ON PAPAYA PRODUCTION WITH TRANSITIONAL GROWERS

    Directory of Open Access Journals (Sweden)

    Octavio Cano-Reyes

    2012-11-01

    Full Text Available Social networks analysis applied to rural innovation processes becomes a very useful technology transfer tool, since it helps to understand the complexity of social relationships among people and/or institutions in their environment, and it also defines those innovation networks given in specific working groups or regions. This study was conducted from April to May 2011 to determine those networks and key players present in the group of growers associated as “Productora y Comercializadora de Papaya de Cotaxtla S.P.R. de R.L.”, that influence the technology transfer process in Cotaxtla, Veracruz, Mexico. Data were analyzed using UCINET 6 software. Three centrality measures were obtained: range, degree of mediation and closeness. Of 32 network players, 27 actively diffuse innovations according to their interests; alliances must be established with them to transfer technology. Four growers stand out as central actors, which along with the Instituto Nacional de Investigaciones Forestales Agricolas y Pecuarias, the Colegio de Postgraduados and the growers’ organization itself, could be the most appropriate actors to establish a technology transfer program to accelerate the diffusion and adoption of innovations. Wholesalers, middlemen and credit institutions do not participate in this process, but having capital they could be incorporated in the innovation diffusion process.

  6. AFRA Network for Education in Nuclear Science and Technology

    International Nuclear Information System (INIS)

    Hashim, O.N.; Wanjala, F.

    2017-01-01

    The Africa Regional Cooperative Agreement for Research Development and Training related to Science and Technology (AFRA) established the AFRA Network for Education in Nuclear Science and Technology (AFRA-NEST) in order to implement AFRA strategy on Human Resource Development (HRD) and Nuclear Knowledge Management (NKM). The strategies for implementing the objectives are: to use ICT for web-based education and training; recognition of Regional Designated Centres (RDCs) for professional nuclear education in nuclear science and technology, and organization of harmonized and accredited programs at tertiary levels and awarding of fellowships/scholarships to young and brilliant students for teaching and research in the various nuclear disciplines

  7. User-friendly Tool for Power Flow Analysis and Distributed Generation Optimisation in Radial Distribution Networks

    Directory of Open Access Journals (Sweden)

    M. F. Akorede

    2017-06-01

    Full Text Available The intent of power distribution companies (DISCOs is to deliver electric power to their customers in an efficient and reliable manner – with minimal energy loss cost. One major way to minimise power loss on a given power system is to install distributed generation (DG units on the distribution networks. However, to maximise benefits, it is highly crucial for a DISCO to ensure that these DG units are of optimal size and sited in the best locations on the network. This paper gives an overview of a software package developed in this study, called Power System Analysis and DG Optimisation Tool (PFADOT. The main purpose of the graphical user interface-based package is to guide a DISCO in finding the optimal size and location for DG placement in radial distribution networks. The package, which is also suitable for load flow analysis, employs the GUI feature of MATLAB. Three objective functions are formulated into a single optimisation problem and solved with fuzzy genetic algorithm to simultaneously obtain DG optimal size and location. The accuracy and reliability of the developed tool was validated using several radial test systems, and the results obtained are evaluated against the existing similar package cited in the literature, which are impressive and computationally efficient.

  8. [Cobatest network: users' characteristics of community-based voluntary,counselling and testing centres in Spain.

    Science.gov (United States)

    Ribas Baltrons, Josep; Fernàndez-López, Laura; Casabona I Barbarà, Jordi

    2017-12-18

    The COBATEST network (European network of community-based voluntary, counselling and testing centers) allows standardized collection of information to monitor HIV testing at these centers. The objective was to describe the performance of the Spanish centers of the COBATEST network and the epidemiological profile of its users, and to analyze the factors associated with having an earlier HIV test. Descriptive analysis of the data collected in the 19 Spanish centers that used the common information collection tools during the year 2015. A multivariate logistic regression model was used to identify factors associated with having an earlier test. A total of 6,077 HIV rapid tests were performed and 1.8% were reactive (3.0% MSM, 3.1% SW, 2.3% PWID, 0.6% heterosexual). 82.1% of the reactives were referred to perform a confirmatory test and 94 (97.9%) were HIV positive, of whom 54% were diverted to the health system. 38% said they had never been tested for HIV. Factors associated with having a previous HIV test were: being over 20 years old; being HSH, SW, or PWID; being foreign; having used condoms at the last penetration; having had an STI in the last year; and having been in jail. The results show the great potential of these services to reach people who have never been tested for HIV. The HIV cases are concentrated in vulnerable groups. It is necessary to improve the linkage of diagnosed people to health care services.

  9. Mobile technology-based interventions for adult users of alcohol: A systematic review of the literature.

    Science.gov (United States)

    Fowler, Lauren A; Holt, Sidney L; Joshi, Deepti

    2016-11-01

    Worldwide, 16% of people aged 15 and older engage in harmful use of alcohol. Harmful alcohol use leads to a host of preventable negative social and health consequences. Mobile technology-based interventions provide a particularly promising avenue for the widespread and cost-effective delivery of treatment that is accessible, affordable, individualized, and destigmatized to both alcohol-dependent and nondependent individuals. The present review sought to summarize the current literature on mobile technology-based interventions among adult users of alcohol and determine the efficacy of such interventions. Five databases were searched in December 2015 (Jan. 2004-Dec. 2015). Inclusion criteria were: participants aged 18 or older, interventions delivered through mobile-technology, and outcome measurement of alcohol reduction/cessation. Eight studies met inclusion criteria. The majority of the studies reviewed found positive effects of the intervention, even though the interventions themselves varied in design, length, dosage, and target population, and were pilot or preliminary in nature. Findings from this review highlight the promising, yet preliminary state of research in this area. Studies with adequate power and valid design are necessary to evaluate the potential of mobile technology-based interventions on long-term alcohol behavior outcomes. Furthermore, future research should elucidate what the most effective length of time is for a mobile technology-based intervention, how often individuals should receive messages for maximum benefit, and determine the comparative effectiveness of mobile technology interventions with other efficacious interventions. Copyright © 2016 Elsevier Ltd. All rights reserved.

  10. Power Consumption Efficiency Evaluation of Multi-User Full-Duplex Visible Light Communication Systems for Smart Home Technologies

    Directory of Open Access Journals (Sweden)

    Muhammad Tabish Niaz

    2017-02-01

    Full Text Available Visible light communication (VLC has recently gained significant academic and industrial attention. VLC has great potential to supplement the functioning of the upcoming radio-frequency (RF-based 5G networks. It is best suited for home, office, and commercial indoor environments as it provides a high bandwidth and high data rate, and the visible light spectrum is free to use. This paper proposes a multi-user full-duplex VLC system using red-green-blue (RGB, and white emitting diodes (LEDs for smart home technologies. It utilizes red, green, and blue LEDs for downlink transmission and a simple phosphor white LED for uplink transmission. The red and green color bands are used for user data and smart devices, respectively, while the blue color band is used with the white LED for uplink transmission. The simulation was carried out to verify the performance of the proposed multi-user full-duplex VLC system. In addition to the performance evaluation, a cost-power consumption analysis was performed by comparing the power consumption and the resulting cost of the proposed VLC system to the power consumed and resulting cost of traditional Wi-Fi based systems and hybrid systems that utilized both VLC and Wi-Fi. Our findings showed that the proposed system improved the data rate and bit-error rate performance, while minimizing the power consumption and the associated costs. These results have demonstrated that a full-duplex VLC system is a feasible solution suitable for indoor environments as it provides greater cost savings and energy efficiency when compared to traditional Wi-Fi-based systems and hybrid systems that utilize both VLC and Wi-Fi.

  11. Single Frequency Network Based Distributed Passive Radar Technology

    Directory of Open Access Journals (Sweden)

    Wan Xian-rong

    2015-01-01

    Full Text Available The research and application of passive radar are heading from single transmitter-receiver pair to multiple transmitter-receiver pairs. As an important class of the illuminators of opportunity, most of modern digital broadcasting and television systems work on Single Frequency Network (SFN, which intrinsically determines that the passive radar based on such illuminators must be distributed and networked. In consideration of the remarkable working and processing mode of passive radar under SFN configuration, this paper proposes the concept of SFN-based Distributed Passive Radar (SDPR. The main characteristics and key problems of SDPR are first described. Then several potential solutions are discussed for part of the key technologies. The feasibility of SDPR is demonstrated by preliminary experimental results. Finally, the concept of four network convergence that includes the broadcast based passive radar network is conceived, and its application prospects are discussed.

  12. Innovation and communicative action: health management networks and technologies

    Directory of Open Access Journals (Sweden)

    Francisco Javier Uribe Rivera

    Full Text Available Abstract: This article discusses elements of a theory of innovation from the perspective of innovation networks and social construction of technology, based on Habermas' Theory of Communicative Action and authors from the Sociology of Innovation. Based on the theoretical framework of the communicative production of scientific facts, we focus on innovation management as a basic dimension that must meet some organizational and methodological requirements in order to power its results. We present and discuss instruments such as Situational Planning, Prospective Analysis, Strategic Portfolio Management, and Networks Management that can help deal with the challenge of innovation and exploration of the future. We conclude that network organizational formats centered on reflexivity of interdisciplinary groups and planning approaches that encourage innovation criteria in assessing the attractiveness of activities and that help anticipate forms of innovation through systematic prospective analysis can potentiate the process of generating innovation as a product of networks.

  13. Home Network Technologies and Automating Demand Response

    Energy Technology Data Exchange (ETDEWEB)

    McParland, Charles

    2009-12-01

    sophisticated energy consumers, it has been possible to improve the DR 'state of the art' with a manageable commitment of technical resources on both the utility and consumer side. Although numerous C & I DR applications of a DRAS infrastructure are still in either prototype or early production phases, these early attempts at automating DR have been notably successful for both utilities and C & I customers. Several factors have strongly contributed to this success and will be discussed below. These successes have motivated utilities and regulators to look closely at how DR programs can be expanded to encompass the remaining (roughly) half of the state's energy load - the light commercial and, in numerical terms, the more important residential customer market. This survey examines technical issues facing the implementation of automated DR in the residential environment. In particular, we will look at the potential role of home automation networks in implementing wide-scale DR systems that communicate directly to individual residences.

  14. User profiles and personas in the design and development of consumer health technologies.

    Science.gov (United States)

    LeRouge, Cynthia; Ma, Jiao; Sneha, Sweta; Tolle, Kristin

    2013-11-01

    "The graying of the globe" has resulted in exponential rise in health care expenses, over-worked health care professionals and a growing patient base suffering from multiple chronic diseases, one of which is diabetes. Consumer health technologies (CHT) are considered important catalysts for empowering health care consumers to take a proactive role in managing their health and related costs. Adoption rate and usability of such devices among the aging is far from being satisfactory. Past studies noted the motivation for adoption by the aging is dependent on the suitability/relevance, perceived usability and anticipated benefits associated with usage of technological innovation. Traditional information technology (IT) development adopts a systematic approach without necessarily using a specific user model that personalizes the system to the aging user groups. The aging patient population has unique needs arising from progressive deterioration in both physiological and psychological abilities. These needs are often ignored in the design, development, trial and adoption of consumer health products resulting in low adoption and usage. The main objective of this research is to investigate the user-centered design (UCD), specifically user profiles and personas, as methodological tools to inform the design and development of CHT devices for an aging population. The adoption of user profile and persona has not received much attention in health care informatics research and, in particular, research involving CHT. Our work begins to fill this void in three ways. We (1) illuminate the process of developing CHT user profiles and personas for a Chinese elder population with a demanding health care needs, i.e., self-management of chronic diabetes, with the hope that the resulting profiles and personas may be used as foundational material for informing the design, development and evaluation of CHT in other similar contexts; (2) call attention to how to further enhance and

  15. Using the ICF in economic analyses of Assistive Technology systems: methodological implications of a user standpoint.

    Science.gov (United States)

    Schraner, Ingrid; De Jonge, Desleigh; Layton, Natasha; Bringolf, Jane; Molenda, Agata

    2008-01-01

    This paper identifies key methodological issues for economic analyses of costs and effectiveness of Assistive Technology (AT) systems based on the International Classification of Functioning, Disability and Health (ICF). Following the biopsychosocial model of the ICF, the paper explores the consequences for cost-effectiveness analyses of AT systems when a user centred approach is taken. In so doing, the paper questions the fiction of neutrality in economic analyses and discusses the distinction between weak and strong objectivity. Costs are measured as all resources used when providing a particular level of environmental facilitators and reducing environmental barriers for an AT user, while effectiveness is measured in terms of the resulting increase in activities and participation of the AT user. The ICF's fourth qualifier for activities and participation, which denotes performance without assistance is used to identify the additional performance achieved due to the particular environmental factors in the current situation (first qualifier). A fifth qualifier for activities and participation is introduced to denote performance with optimal assistance, and the fourth qualifier is then again used to identify the increase in activities and participation due to the environmental factors in the situation with optimal assistance. The effectiveness that an AT user achieves in his or her current situation can be compared with the effectiveness he or she could achieve when provided with what is considered an optimal AT system based on current technologies and user priorities. This comparison throws into sharp relief the role of AT systems as well as of universal design (UD) in reducing environmental barriers for AT users in a way that is cost-effective for society as a whole. Cost-effectiveness analysis based on the ICF can provide powerful economic evidence for how best to allocate existing funding for AT systems. We can identify three particular scenarios in which clear

  16. Improving the installation of renewable heating technology in UK social housing properties through user centred design.

    Science.gov (United States)

    Moore, Natalie; Haines, Victoria; Lilley, Debra

    2015-11-01

    Social housing organisations are increasingly installing renewable energy technologies, particularly for the provision of heating and hot water. To meet carbon reduction targets, uptake and installation must allow occupants to use the technology effectively. This paper describes research which investigated the service of installing heat pumps into UK social housing properties, from both landlords' and tenants' experiences. Adopting a user centred design approach, the research was in three phases: an exploration study to investigate landlords' and tenants' experiences of heat pump installation and use; refinement and development of the requirements for improved service delivery, primarily technology introduction and control; and the development and initial evaluation of an information leaflet as a key touchpoint in the service delivery. Recommendations for improved service delivery, to enable heat pumps to be accepted and used more effectively, are presented, as well as reflection on the process of applying user centred design in this context. In a relatively immature area of industry, installations to date have been heavily focused on technical aspects. This paper provides an insight into the human aspects of the service delivery of heat pumps in social housing, providing designers and social housing landlords with insight about how to improve the service.

  17. Louisiana coastal GIS network: Graphical user interface for access to spatial data

    Science.gov (United States)

    Hiland, Matteson; McBride, Randolph A.; Davis, Donald; Braud, Dewitt; Streiffer, Henry; Jones, Farrell; Lewis, Anthony; Williams, S.

    1991-01-01

    Louisiana's coastal wetlands support a large percentage of the nation's seafood and fur industries, vast deposits of oil and natural gas, habitat for thousands of species of plants and animals, winter nesting grounds and migratory paths for numerous waterfowl, and many recreational resources enjoyed by residents and tourists. Louisiana's wetlands also have the highest rates of coastal erosion and wetland loss in the nation. While numerous studies across many disciplines have been conducted on both local and regional scales, no complete inventory exists for this information. The Louisiana Coastal Geographic Information System Network (LCGISN) is currently being developed to facilitate access to existing data for coastal zone planners, managers, and researchers. The Louisiana Geological Survey (LGS), in cooperation with the LSU Department of Geography and Anthropology, the Computer Aided Design and Geographic Information Systems Research Laboratory (CADGIS), and others, is pursuing this project under the terms of a cooperative agreement with the U.S. Geological Survey. LCGISN is an automated system for searching and retrieving geographic, cartographic, and bibliographic data. By linking original programming with an existing GIS software package and an industry standard relational database management system, LCGISN will provide the capability for users to search for data references by interactively defining the area of interest on a displayed map/image reference background. Several agencies will be networked to provide easy access to a wide variety of information. LCGISN, with its headquarters at LGS, will serve as the central node on the network, providing data format conversions, projection and datum transformations, and storage of several of the most commonly used data sets. Thematic mapper data, USGS 7.5-minute quadrangle map boundaries, political and legal boundaries, major transportation routes, and other digital data will provide a base map to aid the user in

  18. The WMO RA VI Regional Climate Centre Network - a support to users in Europe

    Science.gov (United States)

    Rösner, S.

    2012-04-01

    Climate, like weather, has no limits. Therefore the World Meteorological Organization (WMO), a specialized United Nations organization, has established a three-level infrastructure to better serve its member countries. This structure comprises Global Producing Centres for Long-range Forecasts (GPCs), Regional Climate Centres (RCCs) and National Meteorological or Hydrometeorological Services (NMHSs), in most cases representing their countries in WMO governance bodies. The elements of this infrastructure are also part of and contribute to the Global Framework for Climate Services (GFCS) agreed to be established by World Climate Conference 3 (WCC-3) and last year's Sixteenth World Meteorological Congress (WMO Cg-XVI). RCCs are the core element of this infrastructure at the regional level and are being establish in all WMO Regional Associations (RAs), i.e. Africa (RA I); Asia (II); South America (III); North America, Central America and the Caribbean (IV); South-West Pacific (V); Europe (VI). Addressing inter-regional areas of common interest like the Mediterranean or the Polar Regions may require inter-regional RCCs. For each region the RCCs follow a user driven approach with regard to governance and structure as well as products generated for the users in the respective region. However, there are common guidelines all RCCs do have to follow. This is to make sure that services are provided based on best scientific standards, are routinely and reliably generated and made available in an operational mode. These guidelines are being developed within WMO and make use of decade-long experience gained in the business of operational weather forecast. Based on the requirements of the 50 member countries of WMO RA VI it was agreed to establish the WMO RCC as a network of centres of excellence that create regional products including long-range forecasts that support regional and national climate activities, and thereby strengthen the capacity of WMO Members in the region to

  19. Work of scientific and technological information under network environment

    International Nuclear Information System (INIS)

    Chen Yingxi; Huang Daifu; Yang Lifeng

    2010-01-01

    With the development of internet and information technology, the work of scientific and technological information is faced with great challenge. This article expounds the new changes of scientific and technological information in enterprise under network environment by giving a minute description on the situation the work faced and characteristic of the work. Not only does it carry out enthusiastic discussion upon problems which are present in the work of scientific and technological information in the company, but puts forward proposals and specific measures as well. Service theory is also offered by adjusting and reforming the resources construction, service ways and the job of providing contents. We should take vigorous action to the research work of scientific and technological information, changing the information directional service into knowledge providing service. (authors)

  20. User Modeling for Point-of-Interest Recommendations in Location-Based Social Networks: The State of the Art

    Directory of Open Access Journals (Sweden)

    Shudong Liu

    2018-01-01

    Full Text Available The rapid growth of location-based services (LBSs has greatly enriched people’s urban lives and attracted millions of users in recent years. Location-based social networks (LBSNs allow users to check-in at a physical location and share daily tips on points of interest (POIs with their friends anytime and anywhere. Such a check-in behavior can make daily real-life experiences spread quickly through the Internet. Moreover, such check-in data in LBSNs can be fully exploited to understand the basic laws of humans’ daily movement and mobility. This paper focuses on reviewing the taxonomy of user modeling for POI recommendations through the data analysis of LBSNs. First, we briefly introduce the structure and data characteristics of LBSNs, and then we present a formalization of user modeling for POI recommendations in LBSNs. Depending on which type of LBSNs data was fully utilized in user modeling approaches for POI recommendations, we divide user modeling algorithms into four categories: pure check-in data-based user modeling, geographical information-based user modeling, spatiotemporal information-based user modeling, and geosocial information-based user modeling. Finally, summarizing the existing works, we point out the future challenges and new directions in five possible aspects.

  1. Effectiveness of Using a Change Management Approach to Convey the Benefits of an Information Security Implementation to Technology Users

    Science.gov (United States)

    Bennett, Jeannine B.

    2012-01-01

    This study addressed the problems associated with users' understanding, accepting, and complying with requirements of security-oriented solutions. The goal of the research was not to dispute existing theory on IT project implementations, but rather to further the knowledge on the topic of technology user acceptance of security-oriented IT…

  2. Interpreting User's Choice of Technologies: A Quantitative Research on Choosing the Best Web-Based Communication Tools

    Science.gov (United States)

    Adebiaye, Richmond

    2010-01-01

    The proliferation of web-based communication tools like email clients vis-a-vis Yahoo mail, Gmail, and Hotmail have led to new innovations in web-based communication. Email users benefit greatly from this technology, but lack of security of these tools can put users at risk of loss of privacy, including identity theft, corporate espionage, and…

  3. User Acceptance of Social Learning Systems in Higher Education: An Application of the Extended Technology Acceptance Model

    Science.gov (United States)

    Akman, Ibrahim; Turhan, Cigdem

    2017-01-01

    This study aims to explore the users' behaviour and acceptance of social media for learning in higher educational institutions with the help of the extended Technology Acceptance Model (TAM). TAM has been extended to investigate how ethical and security awareness of users affect the actual usage of social learning applications. For this purpose, a…

  4. The internet of things and the development of network technology in China

    Science.gov (United States)

    Wang, Ruxin; Zhao, Jianzhen; Ma, Hangtong

    2018-04-01

    The English name of the Internet of Things the Internet of Things, referred to as: the IOT. Internet of Things through the pass, radio frequency identification technology, global positioning system technology, real-time acquisition of any monitoring, connectivity, interactive objects or processes, collecting their sound, light, heat, electricity, mechanics, chemistry, biology, the location of a variety of the information you need network access through a variety of possible things and things, objects and people in the Pan-link intelligent perception of items and processes, identification and management. The Internet of Things IntelliSense recognition technology and pervasive computing, ubiquitous network integration application, known as the third wave of the world's information industry development following the computer, the Internet. Not so much the Internet of Things is a network, as Internet of Things services and applications, Internet of Things is also seen as Internet application development. Therefore, the application of innovation is the core of the development of Internet of Things, and 2.0 of the user experience as the core innovation is the soul of Things.

  5. Research on HFC network broadband access using WLAN technology

    Science.gov (United States)

    Chang, Yuguang; Liu, Deming; Zhang, Shu; Wu, Guangsheng

    2007-11-01

    Current broadband access system such as ADSL can not satisfy the network applications as the development of network services. In this paper, we proposed to use WLAN technology on the HFC network as a terminal broadband access plan. First of all, theoretical analysis is given to support the feasibility of using WLAN technology on the HFC network. Then, transmission experiments and results of the proposed plan are described in this paper. The key point of the plan is to use a WLAN access point device as a modem to modulate the baseband Ethernet signal into 2.4GHz WLAN signal which then be transmitted via coaxial cable(COAX). The experimental results show that the average traffic throughput of the system could reach to approximate 20Mbps which is the theoretical throughput of 802.11g WLAN transmission. And the transmission throughput has no remarkable change no matter there is CATV signal in the system or not. Finally, conclusions are drawn out: The proposed system can work properly. WLAN signal is quite suitable to be transmitted in the coaxial cable. CATV signal and WLAN signal are not interfering with each other in the system. Using WLAN on the existing coaxial cable which has already accessed to thousands of people's home could be a cost-effective plan for broadband access on the HFC network.

  6. RSSI-Based User Centric Anonymization for Location Privacy in Vehicular Networks

    Science.gov (United States)

    Wei, Yu-Chih; Chen, Yi-Ming; Shan, Hwai-Ling

    In Vehicular Networks, for enhancing driving safety as well as supporting other applications, vehicles periodically broadcast safety messages with their precise position information to neighbors. However, these broadcast messages make it easy to track specific vehicles and will likely lead to compromise of personal privacy. Unfortunately, current location privacy enhancement methodologies in VANET, including Pseudonymization, K-anonymity, Random silent period, Mix-zones and path confusion, all suffer some shortcomings. In this paper, we propose a RSSI (Received Signal Strength Indicator)-based user centric anonymization model, which can significantly enhance the location privacy and at the same time ensure traffic safety. Simulations are performed to show the advantages of the proposed method. In comparison with traditional random silent period method, our method can increase at least 47% of anonymity in both simple and correlation tracking.

  7. Effect of users' opinion evolution on information diffusion in online social networks

    Science.gov (United States)

    Zhu, Hengmin; Kong, Yuehan; Wei, Jing; Ma, Jing

    2018-02-01

    The process of topic propagation always interweaves information diffusion and opinion evolution, but most previous works studied the models of information diffusion and opinion evolution separately, and seldom focused on their interaction of each other. To shed light on the effect of users' opinion evolution on information diffusion in online social networks, we proposed a model which incorporates opinion evolution into the process of topic propagation. Several real topics propagating on Sina Microblog were collected to analyze individuals' propagation intentions, and different propagation intentions were considered in the model. The topic propagation was simulated to explore the impact of different opinion distributions and intervention with opposite opinion on information diffusion. Results show that the topic with one-sided opinions can spread faster and more widely, and intervention with opposite opinion is an effective measure to guide the topic propagation. The earlier to intervene, the more effectively the topic propagation would be guided.

  8. An Enhanced Dynamic User Optimal Passenger Flow Assignment Model for Metro Networks

    Directory of Open Access Journals (Sweden)

    Hanchuan Pan

    2017-01-01

    Full Text Available By considering the difference between a car driver’s route choice behavior on the road and a passenger’s route choice behavior in urban rail transit (URT, this paper proposes an enhanced Dynamic User Optimal (DUO passenger flow assignment model for metro networks. To capture realistic URT phenomena, the model has integrated the train operation disturbance constraint. Real passenger and train data are used to verify the proposed model and algorithm. The results indicate that the DUO-based model is more suitable for describing passenger route choice behavior under uncertain conditions compared to a static model. Moreover, this paper found that passengers under oversaturated conditions are more sensitive to train operation disturbances compared to undersaturated passengers.

  9. Gene network analysis in plant development by genomic technologies.

    Science.gov (United States)

    Wellmer, Frank; Riechmann, José Luis

    2005-01-01

    The analysis of the gene regulatory networks underlying development is of central importance for a better understanding of the mechanisms that control the formation of the different cell-types, tissues or organs of an organism. The recent invention of genomic technologies has opened the possibility of studying these networks at a global level. In this paper, we summarize some of the recent advances that have been made in the understanding of plant development by the application of genomic technologies. We focus on a few specific processes, namely flower and root development and the control of the cell cycle, but we also highlight landmark studies in other areas that opened new avenues of experimentation or analysis. We describe the methods and the strategies that are currently used for the analysis of plant development by genomic technologies, as well as some of the problems and limitations that hamper their application. Since many genomic technologies and concepts were first developed and tested in organisms other than plants, we make reference to work in non-plant species and compare the current state of network analysis in plants to that in other multicellular organisms.

  10. Topological Interference Management for K-User Downlink Massive MIMO Relay Network Channel.

    Science.gov (United States)

    Selvaprabhu, Poongundran; Chinnadurai, Sunil; Li, Jun; Lee, Moon Ho

    2017-08-17

    In this paper, we study the emergence of topological interference alignment and the characterizing features of a multi-user broadcast interference relay channel. We propose an alternative transmission strategy named the relay space-time interference alignment (R-STIA) technique, in which a K -user multiple-input-multiple-output (MIMO) interference channel has massive antennas at the transmitter and relay. Severe interference from unknown transmitters affects the downlink relay network channel and degrades the system performance. An additional (unintended) receiver is introduced in the proposed R-STIA technique to overcome the above problem, since it has the ability to decode the desired signals for the intended receiver by considering cooperation between the receivers. The additional receiver also helps in recovering and reconstructing the interference signals with limited channel state information at the relay (CSIR). The Alamouti space-time transmission technique and minimum mean square error (MMSE) linear precoder are also used in the proposed scheme to detect the presence of interference signals. Numerical results show that the proposed R-STIA technique achieves a better performance in terms of the bit error rate (BER) and sum-rate compared to the existing broadcast channel schemes.

  11. LNS users primer for accessing government sites on the ARPA network. [MIT. -->. ANL, BNL, LBL, and New York Univ. Courant Inst

    Energy Technology Data Exchange (ETDEWEB)

    Kannel, M.

    1979-06-01

    This primer was developed as part of the study conducted by the Laboratory for Nuclear Science (LNS) on the feasibility of networks for computer resource sharing. The primer is an instructinal guide for the LNS user who would like to access and use computers at other government sites on the ARPA network. The format is a series of scenarios of actual recorded on-line terminal sessions' showing the novice user how to access the foreign site, obtain help documentation, run a simple program, and transfer files to and from the foreign site. Access to the ARPA network in these scenarios is via Multics or the Massachusetts Institute of Technology Terminal Interface Processor. The foreign government sites accessed are the computing facilities at Argonne National Laboratory, Brookhaven National Laboratory, Lawrence Livermore Laboratory, and New York University Courant Institute. This technique of auditing actual terminal sessions as a teaching aid can be extended to include other computing facilities as well as other networks.

  12. An Improved Digital Signature Protocol to Multi-User Broadcast Authentication Based on Elliptic Curve Cryptography in Wireless Sensor Networks (WSNs

    Directory of Open Access Journals (Sweden)

    Hamed Bashirpour

    2018-03-01

    Full Text Available In wireless sensor networks (WSNs, users can use broadcast authentication mechanisms to connect to the target network and disseminate their messages within the network. Since data transfer for sensor networks is wireless, as a result, attackers can easily eavesdrop deployed sensor nodes and the data sent between them or modify the content of eavesdropped data and inject false data into the sensor network. Hence, the implementation of the message authentication mechanisms (in order to avoid changes and injecting messages into the network of wireless sensor networks is essential. In this paper, we present an improved protocol based on elliptic curve cryptography (ECC to accelerate authentication of multi-user message broadcasting. In comparison with previous ECC-based schemes, complexity and computational overhead of proposed scheme is significantly decreased. Also, the proposed scheme supports user anonymity, which is an important property in broadcast authentication schemes for WSNs to preserve user privacy and user untracking.

  13. Online public health preparedness training programs: an evaluation of user experience with the technological environment.

    Science.gov (United States)

    Nambisan, Priya

    2010-01-01

    Several public health education programs and government agencies across the country have started offering virtual or online training programs in emergency preparedness for people who are likely to be involved in managing or responding to different types of emergency situations such as natural disasters, epidemics, bioterrorism, etc. While such online training programs are more convenient and cost-effective than traditional classroom-based programs, their success depends to a great extent on the underlying technological environment. Specifically, in an online technological environment, different types of user experiences come in to play-users' utilitarian or pragmatic experience, their fun or hedonic experience, their social experience, and most importantly, their usability experience-and these different user experiences critically shape the program outcomes, including course completion rates. This study adopts a multi-disciplinary approach and draws on theories in human computer interaction, distance learning theories, usability research, and online consumer behavior to evaluate users' experience with the technological environment of an online emergency preparedness training program and discusses its implications for the design of effective online training programs. . Data was collected using a questionnaire from 377 subjects who had registered for and participated in online public health preparedness training courses offered by a large public university in the Northeast. Analysis of the data indicates that as predicted, participants had higher levels of pragmatic and usability experiences compared to their hedonic and sociability experiences. Results also indicate that people who experienced higher levels of pragmatic, hedonic, sociability and usability experiences were more likely to complete the course(s) they registered for compared to those who reported lower levels. The study findings hold important implications for the design of effective online emergency

  14. Social network members' roles and use of mental health services among drug users in New York City.

    Science.gov (United States)

    Sapra, Katherine J; Crawford, Natalie D; Rudolph, Abby E; Jones, Kandice C; Benjamin, Ebele O; Fuller, Crystal M

    2013-10-01

    Depression is more common among drug users (15-63 %) than the general population (5-16 %). Lack of social support network members may be associated with low mental health service (MHS) use rates observed among drug users. We investigated the relationship between social network members' roles and MHS use among frequent drug users using Social Ties Associated with Risk of Transition into Injection Drug Use data (NYC 2006-2009). Surveys assessed depression, MHS use, demographics, drug use and treatment, and social network members' roles. Participants reporting lifetime depressive episode with start/end dates and information on social/risk network members were included (n = 152). Adjusting for emotional support and HIV status, having one or more informational support network members remained associated with MHS use at last depressive episode (adjusted odds ratio (AOR) 3.37, 95 % confidence interval (CI) 1.38-8.19), as did history of drug treatment (AOR 2.75, 95 % CI 1.02-7.41) and no legal income (AOR 0.23, 95 % CI 0.08-0.64). These data suggest that informational support is associated with MHS utilization among depressed drug users.

  15. Online technology use in physiotherapy teaching and learning: a systematic review of effectiveness and users' perceptions.

    Science.gov (United States)

    Mącznik, Aleksandra K; Ribeiro, Daniel Cury; Baxter, G David

    2015-09-28

    The use of online technologies in health professionals' education, including physiotherapy, has been advocated as effective and well-accepted tools for enhancing student learning. The aim of this study was to critically review the effectiveness, and user perceptions of online technology for physiotherapy teaching and learning. Following databases were systematically searched on the 31(st) of August 2013 for articles describing implementation of online technologies into physiotherapy teaching and learning: ERIC, CINAHL, Web of Science, Academic search complete, ProQuest Nursing and Allied Health Source, Medline, Embase, and Scopus. No language, design or publishing date restrictions were imposed. Risk of bias was assessed using the 2011 Mixed Methods Appraisal Tool checklist (MMAT). A total of 4133 articles were retrieved; 22 articles met the inclusion criteria and were accepted for final analysis: 15 on the effectiveness of technology, and 14 on users' perceptions. Included studies used three designs: case study (14 articles), controlled trial (3), and randomized controlled trial (5). Studies investigated both pre-registration physiotherapy students (1523) and physiotherapy professionals (171). The quality of studies ranged from 67 to 100 % on the MMAT checklist which can be considered moderate to excellent. More than half of the studies (68 %) received scores greater than 80 %. Studies typically investigated websites and discussion boards. The websites are effective in enhancing practical skills performance, and discussion boards in knowledge acquisition, as well as in development of critical and reflective thinking. Students' perceptions of the use of websites were mostly positive, providing students with entertaining, easy accessible resources. Perceived barriers to the use of websites included difficulties with internet connection, insufficiently interactive material, or personal preference for paper-based materials. Discussion boards were perceived as

  16. Technology Transfer Challenges: A Case Study of User-Centered Design in NASA's Systems Engineering Culture

    Science.gov (United States)

    Quick, Jason

    2009-01-01

    The Upper Stage (US) section of the National Aeronautics and Space Administration's (NASA) Ares I rocket will require internal access platforms for maintenance tasks performed by humans inside the vehicle. Tasks will occur during expensive critical path operations at Kennedy Space Center (KSC) including vehicle stacking and launch preparation activities. Platforms must be translated through a small human access hatch, installed in an enclosed worksite environment, support the weight of ground operators and be removed before flight - and their design must minimize additional vehicle mass at attachment points. This paper describes the application of a user-centered conceptual design process and the unique challenges encountered within NASA's systems engineering culture focused on requirements and "heritage hardware". The NASA design team at Marshall Space Flight Center (MSFC) initiated the user-centered design process by studying heritage internal access kits and proposing new design concepts during brainstorming sessions. Simultaneously, they partnered with the Technology Transfer/Innovative Partnerships Program to research inflatable structures and dynamic scaffolding solutions that could enable ground operator access. While this creative, technology-oriented exploration was encouraged by upper management, some design stakeholders consistently opposed ideas utilizing novel, untested equipment. Subsequent collaboration with an engineering consulting firm improved the technical credibility of several options, however, there was continued resistance from team members focused on meeting system requirements with pre-certified hardware. After a six-month idea-generating phase, an intensive six-week effort produced viable design concepts that justified additional vehicle mass while optimizing the human factors of platform installation and use. Although these selected final concepts closely resemble heritage internal access platforms, challenges from the application of the

  17. On the Impact of Closed Access and Users Identities in Spectrum-Shared Overlaid Wireless Networks

    KAUST Repository

    Radaydeh, Redha M.

    2016-03-28

    © 2015 IEEE. This paper develops analytical models to investigate the impact of various operation terms and parameters on the downlink performance of spectrum-shared overlaid networks under closed-access small cells deployment. It is considered that closed-access small cells (i.e., femtocells) can not reuse available channels, and can serve only active authorized user equipments (UEs). On the other hand, the macrocell base station can unconditionally reuse available channels to serve active macrocell UEs. The analysis characterizes UEs identities, their likelihoods of being active, and their likelihoods of initiating interference. Moreover, it quantifies interference sources observed from effective femtocells considering their over-loaded and under-loaded cell scenarios. The developed results to characterize an active UE performance and the impact of the number of available channels are thoroughly examined. The obtained results are generally applicable for any performance measure and any network channel models. Numerical and simulation examples are presented to clarify the main outcomes of this paper.

  18. OMENTIN - information network about mining and environmental technologies

    Directory of Open Access Journals (Sweden)

    Balazs Bodo

    2002-09-01

    Full Text Available The European mining industry faces increasing challenges to meet the environmental requirements and to convince the local communities over the need and benefit of its existence. Communities and residents near mine sites have increasing concern over the use of the different mining and processing technologies. They need to know the scientific background of these technologies ,their impact on the environment and the risks involved. This information, which normally comes from authorities, companies should be detailed, simple, transparent and unbiased. To access the public and provide them with such information. improved techniques and multinational network are needed. In this network mining professionals and environmentalist should find common language and platform to discuss the benefits and hazards of mining and formulate joint opinions.. The OMENTIN projects aims to establish and develop this platform, and attempts to develop.

  19. The Networking and Information Technology Research and Development NITRD Program 2012 Strategic Plan

    Data.gov (United States)

    Networking and Information Technology Research and Development, Executive Office of the President — Information technology IT computers, wired and wireless digital networks, electronic data and information, IT devices and systems, and software applications?today...

  20. EDENetworks: A user-friendly software to build and analyse networks in biogeography, ecology and population genetics

    OpenAIRE

    Kivela, Mikko; Arnaud-haond, Sophie; Saramaki, Jari

    2015-01-01

    The recent application of graph-based network theory analysis to biogeography, community ecology and population genetics has created a need for user-friendly software, which would allow a wider accessibility to and adaptation of these methods. EDENetworks aims to fill this void by providing an easy-to-use interface for the whole analysis pipeline of ecological and evolutionary networks starting from matrices of species distributions, genotypes, bacterial OTUs or populations characterized gene...

  1. Do social networks and technological capabilities help knowledge management?

    OpenAIRE

    Encarnación García-Sánchez; Víctor Jesús García-Morales; Rodrigo Martín-Rojas

    2017-01-01

    Dynamic capabilities are currently becoming an important extension of the theory of resources and capabilities that enables companies to adapt better in the current competitive environment. This paper examines how knowledge management, a dynamic function related to management or administration of a set of knowledge flows, develops thanks to the greater dynamism of social networks. It then shows how this relationship is especially strengthened by different technological capabilities. To achiev...

  2. Innovation and communicative action: health management networks and technologies

    OpenAIRE

    Rivera,Francisco Javier Uribe; Artmann,Elizabeth

    2016-01-01

    Abstract: This article discusses elements of a theory of innovation from the perspective of innovation networks and social construction of technology, based on Habermas' Theory of Communicative Action and authors from the Sociology of Innovation. Based on the theoretical framework of the communicative production of scientific facts, we focus on innovation management as a basic dimension that must meet some organizational and methodological requirements in order to power its results. We presen...

  3. Matching user needs to technology in dementia care: experiences with the Alma Supervisor Educational Program

    Directory of Open Access Journals (Sweden)

    Torhild Holthe

    2016-12-01

    Full Text Available The number of individuals with dementia in Norway is more than 78,000, and, as in all other European countries, this figure is expected to rise over the coming decades. The Norwegian Health Directorate encourages municipalities to make use of ‘welfare technology’ in order to contribute to independent living and quality of life in older adults, to increase the quality of community health care, to save time when providing community health services and to reduce costs, e.g. admission to a nursing home. Introducing welfare technology to care recipients requires innovation on the part of the community health care service with regard to increasing the competency of the staff in the operation of the technologies, as well as in establishing an infrastructure for ‘digital communication’. Research has shown that access to assistive technology may support individuals with mild cognitive impairments, as well as in an early phase of dementia. However, it is crucial that the technology addresses an identified need, and that the device is tailored to the person’s preferences and context. Therefore, it is important to train health professionals to assess the user’s needs and preferences and to identify resources and limitations in the particular context. Alma’s House in Oslo is a demonstration site and education center for welfare technologies. The education program for the certification of Alma supervisors has become an important strategy in educating occupational therapists (OTs and nurses on how to assess user needs, identify appropriate technology and implement this into the care recipient’s home.

  4. Perceived Values and Prospective Users' Acceptance of Prospective Technology: The Case of a Career ePortfolio System

    Science.gov (United States)

    Tzeng, Jeng-Yi

    2011-01-01

    Technology-acceptance tests are traditionally conducted after users have obtained at least a certain amount of experience with a technology. Taking college students who had no real interaction with a prospective eportfolio system, this study investigated both their perceptions of the system and the perceptions' association with attitude towards…

  5. Sexual transmissibility of HIV among opiates users with concurrent sexual partnerships: An egocentric network study in Yunnan, China

    Science.gov (United States)

    Li, Jian; Liu, Hongjie; Li, Jianhua; Luo, Jian; Koram, Nana; Detels, Roger

    2011-01-01

    Aims To investigate the patterns of concurrent sexual partnerships among young opiate users and sexual transmissibility of HIV in concurrent sexual partnerships in drug-use and sexual networks. Design Cross-sectional design. Participants 426 young opiate users in Yunnan, China. Measurement Respondent-driven sampling (RDS) was used to recruit participants. Multiple logistic regressions were performed to analyze the relationships of concurrent sexual partnerships with egocentric social network components, risky sexual behavior for HIV, and drug-use practices. Findings The RDS-adjusted prevalence of concurrent sexual partners was 42.9% among opiate users. Opiate users with concurrent sexual partnerships were more likely to engage in risky HIV-related sexual behavior, compared to those without. Specifically, they were more likely to report having had four or more sexual partners (26.3% vs. 2.0%), having had a spouse or boy/girl friends who also had concurrent sexual partnerships (28.1% vs. 8.2%), having exchanged drug for sex (12.4% vs. 3.8%), having had sexual partners who were non-injection drug users (22.6% vs. 10.1%), having had sexual partners who were injection drug users (25.3% vs. 13.5%), and having used club drugs (26.3% vs. 13.5%). There were no significant differences in consistent condom use between opiate users with sexual concurrency and those without. The same proportion (25.8%) of opiate users in the two groups reported having consistently used condoms when having sex with regular partners, and 46.3% of opiate users with sexual concurrency and 36.4% of those without such concurrency consistently used condoms with non-regular partners. Conclusion The expansion of the HIV epidemic from high risk populations to the general population in China may be driven by concurrent sexual partnerships. Behavioral interventions targeting safer sex should be integrated into harm reduction programmes. PMID:21457169

  6. Social networks and social functioning level among occupational therapy workshops and community-based support centers users.

    Science.gov (United States)

    Bronowski, Paweł; Sawicka, Maryla; Rowicka, Magda; Bronowska, Marta

    2017-02-26

    Community-Based Support Centers (CSC) and Occupational Therapy Workshops (OTW) have been functioning for over 20 years in Poland. However, the effectiveness of their rehabilitation programs as well as the users profile has not been examined yet. The aim of the study was to determine social functioning level and support network effectiveness of CSC and OTW users. Research tools: GAS (Global Assessment Scale), social network and social support assessment, Social Functioning Scale, Sociodemographic Questionnaire. Results show that investigated groups (except for participants' age) show no significant differences in sociodemographic variables and illness profile. Significant differences were found in the aspect of number and quality of support networks and the functioning level. Analyzed support institutions have different aims and offer different support programs which show differences in support networks and social functioning level. It can result from that the goal of OTW is to activate its users and assist them with their reintegration into the labor market, whereas CSCs are oriented on users' current issues and hospitalization prevention. It is important to have knowledge of these specifics during referring a person to such service.

  7. Effects of Pre-Purchase Search Motivation on User Attitudes toward Online Social Network Advertising: A Case of University Students

    Directory of Open Access Journals (Sweden)

    Imran A Mir

    2014-06-01

    Full Text Available Since last few years, social media have profoundly changed the ways of social and business communication. Particularly, social network sites (SNSs have rapidly grown in popularity and number of users globally. They have become the main place for social interaction, discussion and communication. Today, businesses of various types use SNSs for commercial communication. Banner advertising is one of the common methods of commercial communication on SNSs. Advertising is a key source of revenue for many SNSs firms such as Facebook. In fact, the existence of many SNSs owners and advertisers is contingent upon the success of social network advertising (SNA. Users demand free SNS services which makes SNA crucial for SNSs firms. SNA can be effective only if it is aligned with user motivations. Marketing literature identifies pre-purchase search as a primary consumer motivation for using media. The current study aims to identify the effects of pre-purchase search motivation (PSM on user attitudes toward SNA. It also assesses the association between the attitudes toward SNA and users’ banner ad-clicking behavior on SNSs. Data was gathered from 200 university students in Islamabad using offline survey. Results show positive effects of PSM on user attitudes toward SNA. They also show positive association between user attitudes toward SNA and their SNS banner ad-clicking behavior. The firms which promote their products through SNSs to the young South Asian consumers may benefit from the findings of the current study.

  8. An Anonymous User Authentication and Key Agreement Scheme Based on a Symmetric Cryptosystem in Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Jaewook Jung

    2016-08-01

    Full Text Available In wireless sensor networks (WSNs, a registered user can login to the network and use a user authentication protocol to access data collected from the sensor nodes. Since WSNs are typically deployed in unattended environments and sensor nodes have limited resources, many researchers have made considerable efforts to design a secure and efficient user authentication process. Recently, Chen et al. proposed a secure user authentication scheme using symmetric key techniques for WSNs. They claim that their scheme assures high efficiency and security against different types of attacks. After careful analysis, however, we find that Chen et al.’s scheme is still vulnerable to smart card loss attack and is susceptible to denial of service attack, since it is invalid for verification to simply compare an entered ID and a stored ID in smart card. In addition, we also observe that their scheme cannot preserve user anonymity. Furthermore, their scheme cannot quickly detect an incorrect password during login phase, and this flaw wastes both communication and computational overheads. In this paper, we describe how these attacks work, and propose an enhanced anonymous user authentication and key agreement scheme based on a symmetric cryptosystem in WSNs to address all of the aforementioned vulnerabilities in Chen et al.’s scheme. Our analysis shows that the proposed scheme improves the level of security, and is also more efficient relative to other related schemes.

  9. Formal Variability of Terms in the Sphere of Network Technologies

    Directory of Open Access Journals (Sweden)

    Roman Viktorovich Deniko

    2015-09-01

    Full Text Available The article addresses the problem of formal variability of terms in the sphere of network terminology in the Russian language. The research is based on data from the Internet communication in the sphere of network technologies. Such formal variability types as graphical, phonemic, word building and complex (graphic and phonetic, morphologic and accentual are discussed in this article. The authors reveal the reasons for graphic variability of foreign origin terms making up the international terminological fund. These reasons cover such aspects as the use of graphics of source language and recipient language; the presence or absence of hyphenation, etc. It is determined that the phonemic variants of terms appear as a result of oral or written borrowings. The existence of such variants is also connected with the stage of their adaptation in the Russian language after borrowing. In this case the variants are related with soft or hard pronunciation of consonants. There are also some cases of phonemic variability on the graphic level. The complex variability is regarded as a part of active processes taking place in the modern Russian language, and these processes involve both native and foreign origin terms. The particular attention is paid to the word-building variants – word-building affixes the variability of which is peculiar of network technologies. The results of the research show that the variability of professional units belonging to the network technologies sublanguage is caused by the active process of borrowing of specialpurpose vocabulary into the Russian language. The process is due to the intensification of intercultural communication in the professional spheres.

  10. Comprehensive support for nuclear decommissioning based on 3D simulation and advanced user interface technologies

    International Nuclear Information System (INIS)

    Szőke, István; Louka, Michael N.; Bryntesen, Tom-Robert; Edvardsen, Svein-Tore; Bratteli, Joachim

    2015-01-01

    There is an increasing international focus on the need to optimise decommissioning strategies, driven by the anticipation of high costs and major effort for the decommissioning of nuclear facilities in the coming decades. The goals are to control and mitigate costs and negative impacts on workers, the general public, and the environment. The methods presently employed for many decommissioning tasks do not apply the latest advancements of science and technology. Therefore, there is growing interest in research and development into the adoption of novel techniques for improving safety, reducing costs, and increasing transparency. This paper provides a comprehensive overview of the authors' results from investigating how current and emerging technologies can be applied to enhance the international decommissioning strategy, focussing in particular on three-dimensional simulation, virtual reality, advanced user interfaces, mobile and wearable devices, and geographical information systems. Our results demonstrate that emerging technologies have great potential for supporting adoption of new instrumentation, improving data and knowledge management, optimising project plans, briefing and training field operators, and for communication, surveillance, and education in general. (author)

  11. The advanced test reactor national scientific user facility advancing nuclear technology

    International Nuclear Information System (INIS)

    Allen, T.R.; Thelen, M.C.; Meyer, M.K.; Marshall, F.M.; Foster, J.; Benson, J.B.

    2009-01-01

    To help ensure the long-term viability of nuclear energy through a robust and sustained research and development effort, the U.S. Department of Energy (DOE) designated the Advanced Test Reactor and associated post-irradiation examination facilities a National Scientific User Facility (ATR NSUF), allowing broader access to nuclear energy researchers. The mission of the ATR NSUF is to provide access to world-class nuclear research facilities, thereby facilitating the advancement of nuclear science and technology. The ATR NSUF seeks to create an engaged academic and industrial user community that routinely conducts reactor-based research. Cost free access to the ATR and PIE facilities is granted based on technical merit to U.S. university-led experiment teams conducting non-proprietary research. Proposals are selected via independent technical peer review and relevance to DOE mission. Extensive publication of research results is expected as a condition for access. During FY 2008, the first full year of ATR NSUF operation, five university-led experiments were awarded access to the ATR and associated post-irradiation examination facilities. The ATR NSUF has awarded four new experiments in early FY 2009, and anticipates awarding additional experiments in the fall of 2009 as the results of the second 2009 proposal call. As the ATR NSUF program mature over the next two years, the capability to perform irradiation research of increasing complexity will become available. These capabilities include instrumented irradiation experiments and post-irradiation examinations on materials previously irradiated in U.S. reactor material test programs. The ATR critical facility will also be made available to researchers. An important component of the ATR NSUF an education program focused on the reactor-based tools available for resolving nuclear science and technology issues. The ATR NSUF provides education programs including a summer short course, internships, faculty-student team

  12. TinCan: User-Defined P2P Virtual Network Overlays for Ad-hoc Collaboration

    Directory of Open Access Journals (Sweden)

    Pierre St Juste

    2014-10-01

    Full Text Available Virtual private networking (VPN has become an increasingly important component of a collaboration environment because it ensures private, authenticated communication among participants, using existing collaboration tools, where users are distributed across multiple institutions and can be mobile. The majority of current VPN solutions are based on a centralized VPN model, where all IP traffic is tunneled through a VPN gateway. Nonetheless, there are several use case scenarios that require a model where end-to-end VPN links are tunneled upon existing Internet infrastructure in a peer-to-peer (P2P fashion, removing the bottleneck of a centralized VPN gateway. We propose a novel virtual network — TinCan — based on peerto-peer private network tunnels. It reuses existing standards and implementations of services for discovery notification (XMPP, reflection (STUN and relaying (TURN, facilitating configuration. In this approach, trust relationships maintained by centralized (or federated services are automatically mapped to TinCan links. In one use scenario, TinCan allows unstructured P2P overlays connecting trusted end-user devices — while only requiring VPN software on user devices and leveraging online social network (OSN infrastructure already widely deployed. This paper describes the architecture and design of TinCan and presents an experimental evaluation of a prototype supporting Windows, Linux, and Android mobile devices. Results quantify the overhead introduced by the network virtualization layer, and the resource requirements imposed on services needed to bootstrap TinCan links.

  13. The Role of Social Networks in Financing High Technology New Ventures: An Empirical Exploration

    NARCIS (Netherlands)

    Heuven, J.M.J.

    2006-01-01

    This paper focuses on the role of networks in financing high technology start-ups. We claim that the role of networks is twofold. On the one hand networks are important because network contacts can give direct access to resources. On the other hand, networks are important because being affiliated

  14. 76 FR 23812 - Reliability and Continuity of Communications Networks, Including Broadband Technologies; Effects...

    Science.gov (United States)

    2011-04-28

    ...] Reliability and Continuity of Communications Networks, Including Broadband Technologies; Effects on Broadband...: Effects on Broadband Communications Networks of Damage or Failure of Network Equipment or Severe Overload... Docket 10-92 (Effects on Broadband Communications Networks of Damage or Failure of Network Equipment or...

  15. Impact of bandwidth for various services in heterogeneous network and quality of service via communication technologies in Malaysian higher educational

    Directory of Open Access Journals (Sweden)

    Mohd Nazri ISMAIL

    2007-12-01

    Full Text Available This study focuses on heterogeneous services and communication technologies for retrieving and sending information between students and lecturers in Malaysian higher educational institutes. It intends to investigate pattern and significant level of various services implementation, convergence of communication technologies and bandwidth capacity for last mile users (students and lecturers. It is designed to determine which communication technologies, services, bandwidth capacity and QoS will achieve the highest level acceptance in Malaysian higher educational institutes. Heterogeneous environment can also generate mobility approaches. A survey method is used to collect data from respondents (System Network Administrator in Malaysian higher educational institutes. Statistical Analysis using t-test shows that implementation of high speed bandwidth for Internet (WAN achieved significant level. Frequency test are used to analyze the various services implementation via convergence of communication technologies in heterogeneous environment for retrieving information. The most apparent finding of this study is that various services implementation in higher educational institutes can affect convergence of communication technologies usage in accessing information over heterogeneous network environment between students and lecturers. The study or analysis confirms that Malaysia higher educational institutes have not achieved a maximum level of various services implementation via convergence of communication technologies between students and lecturers in heterogeneous network environment. Therefore, low convergence of communication technologies can produce a low mobility and ubiquitous interaction between students and lectures in Malaysian higher educational institutes.

  16. Future artificial pancreas technology for type 1 diabetes: what do users want?

    Science.gov (United States)

    Barnard, Katharine D; Pinsker, Jordan E; Oliver, Nick; Astle, Annabel; Dassau, Eyal; Kerr, David

    2015-05-01

    The primary focus of artificial pancreas (AP) research has been on technical achievements, such as time in range for glucose levels or prevention of hypoglycemia. Few studies have attempted to ascertain the expectations of users of AP technology. Persons with type 1 diabetes and parents of children with type 1 diabetes were invited to take part in an online survey concerning future use and expectations of AP technology. The survey was advertised via Twitter, Facebook, and DiabetesMine, plus advocacy groups and charities including INPUT, Diabetes UK, and the Diabetes Research and Wellness Foundation. Quantitative responses were categorized on a 5-point Likert scale. Free text responses were analyzed using content analysis. Two hundred sixty-six surveys were completed over a 1-month period. Two hundred forty participants indicated they were highly likely to use a fully automated 24-h AP. Approximately half of the respondents indicated they would be likely to use a device that only functioned overnight. Size, visibility, and lack of effectiveness were the top reasons for not wanting an AP. Despite perceived potential downsides, participants expressed a strong need for a device that will help minimize the burden of disease, help facilitate improved psychosocial functioning, and improve quality of life. The views of people who would use an AP are crucial in the development of such devices to ensure they are fit for use alongside biomedical and engineering excellence. Without this, it is unlikely that an AP will be sufficiently successful to meet the needs of users and to achieve their ultimate goals.

  17. Innovative Networking Concepts Tested on the Advanced Communications Technology Satellite

    Science.gov (United States)

    Friedman, Daniel; Gupta, Sonjai; Zhang, Chuanguo; Ephremides, Anthony

    1996-01-01

    This paper describes a program of experiments conducted over the advanced communications technology satellite (ACTS) and the associated TI-VSAT (very small aperture terminal). The experiments were motivated by the commercial potential of low-cost receive only satellite terminals that can operate in a hybrid network environment, and by the desire to demonstrate frame relay technology over satellite networks. The first experiment tested highly adaptive methods of satellite bandwidth allocation in an integrated voice-data service environment. The second involved comparison of forward error correction (FEC) and automatic repeat request (ARQ) methods of error control for satellite communication with emphasis on the advantage that a hybrid architecture provides, especially in the case of multicasts. Finally, the third experiment demonstrated hybrid access to databases and compared the performance of internetworking protocols for interconnecting local area networks (LANs) via satellite. A custom unit termed frame relay access switch (FRACS) was developed by COMSAT Laboratories for these experiments; the preparation and conduct of these experiments involved a total of 20 people from the University of Maryland, the University of Colorado and COMSAT Laboratories, from late 1992 until 1995.

  18. An Overview on Wireless Sensor Networks Technology and Evolution

    Directory of Open Access Journals (Sweden)

    Chiara Buratti

    2009-08-01

    Full Text Available Wireless sensor networks (WSNs enable new applications and require non-conventional paradigms for protocol design due to several constraints. Owing to the requirement for low device complexity together with low energy consumption (i.e., long network lifetime, a proper balance between communication and signal/data processing capabilities must be found. This motivates a huge effort in research activities, standardization process, and industrial investments on this field since the last decade. This survey paper aims at reporting an overview of WSNs technologies, main applications and standards, features in WSNs design, and evolutions. In particular, some peculiar applications, such as those based on environmental monitoring, are discussed and design strategies highlighted; a case study based on a real implementation is also reported. Trends and possible evolutions are traced. Emphasis is given to the IEEE 802.15.4 technology, which enables many applications of WSNs. Some example of performance characteristics of 802.15.4-based networks are shown and discussed as a function of the size of the WSN and the data type to be exchanged among nodes.

  19. Enhanced Quality of Service of Cell-Edge User by Extending Modified Largest Weighted Delay First Algorithm in LTE Networks

    Directory of Open Access Journals (Sweden)

    Hasibur Rashid Chayon

    2017-05-01

    Full Text Available Long Term Evolution (LTE is the prominent technology in Fourth Generation (4G communication standards, which provides higher throughput and better Quality of Service (QoS to all users. However, users in the cell-edge area are receiving comparatively low QoS due to the distance from eNodeB (eNB and bad channel conditions. The Conventional Modified Largest Weighted Delay First (MLWDF algorithm is unable to resolve this issue, as it does not consider the location of the user. This paper proposes an extended MLWDF (EMLWDF downlink scheduling algorithm to provide better services to the cell-edge user as well as to the cell-center user. The proposed algorithm divides the eNB cell area into inner and outer regions. It includes the distance of the user from attached eNB, received Signal to Interference plus Noise Ratio (SINR and error probability into the original algorithm. The simulated results are compared with other well-known algorithms and the comparison shows that the proposed algorithm enhances overall 56.23% of cell-edge user throughput and significantly improves the average user throughput, fairness index, and spectral efficiency.

  20. Optimal Multiuser Diversity in Multi-Cell MIMO Uplink Networks: User Scaling Law and Beamforming Design

    Directory of Open Access Journals (Sweden)

    Bang Chul Jung

    2017-07-01

    Full Text Available We introduce a distributed protocol to achieve multiuser diversity in a multicell multiple-input multiple-output (MIMO uplink network, referred to as a MIMO interfering multiple-access channel (IMAC. Assuming both no information exchange among base stations (BS and local channel state information at the transmitters for the MIMO IMAC, we propose a joint beamforming and user scheduling protocol, and then show that the proposed protocol can achieve the optimal multiuser diversity gain, i.e., KMlog(SNRlog N, as long as the number of mobile stations (MSs in a cell, N, scales faster than SNR K M − L 1 − ϵ for a small constant ϵ > 0, where M, L, K, and SNR denote the number of receive antennas at each BS, the number of transmit antennas at each MS, the number of cells, and the signal-to-noise ratio, respectively. Our result indicates that multiuser diversity can be achieved in the presence of intra-cell and inter-cell interference even in a distributed fashion. As a result, vital information on how to design distributed algorithms in interference-limited cellular environments is provided.

  1. The Advanced Test Reactor National Scientific User Facility Advancing Nuclear Technology

    International Nuclear Information System (INIS)

    Allen, T.R.; Benson, J.B.; Foster, J.A.; Marshall, F.M.; Meyer, M.K.; Thelen, M.C.

    2009-01-01

    To help ensure the long-term viability of nuclear energy through a robust and sustained research and development effort, the U.S. Department of Energy (DOE) designated the Advanced Test Reactor and associated post-irradiation examination facilities a National Scientific User Facility (ATR NSUF), allowing broader access to nuclear energy researchers. The mission of the ATR NSUF is to provide access to world-class nuclear research facilities, thereby facilitating the advancement of nuclear science and technology. The ATR NSUF seeks to create an engaged academic and industrial user community that routinely conducts reactor-based research. Cost free access to the ATR and PIE facilities is granted based on technical merit to U.S. university-led experiment teams conducting non-proprietary research. Proposals are selected via independent technical peer review and relevance to DOE mission. Extensive publication of research results is expected as a condition for access. During FY 2008, the first full year of ATR NSUF operation, five university-led experiments were awarded access to the ATR and associated post-irradiation examination facilities. The ATR NSUF has awarded four new experiments in early FY 2009, and anticipates awarding additional experiments in the fall of 2009 as the results of the second 2009 proposal call. As the ATR NSUF program mature over the next two years, the capability to perform irradiation research of increasing complexity will become available. These capabilities include instrumented irradiation experiments and post-irradiation examinations on materials previously irradiated in U.S. reactor material test programs. The ATR critical facility will also be made available to researchers. An important component of the ATR NSUF an education program focused on the reactor-based tools available for resolving nuclear science and technology issues. The ATR NSUF provides education programs including a summer short course, internships, faculty-student team

  2. Salience and default mode network dysregulation in chronic cocaine users predict treatment outcome.

    Science.gov (United States)

    Geng, Xiujuan; Hu, Yuzheng; Gu, Hong; Salmeron, Betty Jo; Adinoff, Bryon; Stein, Elliot A; Yang, Yihong

    2017-05-01

    While chronic cocaine use is associated with abnormalities in both brain structure and function within and interactions between regions, previous studies have been limited to interrogating structure and function independently, and the detected neural differences have not been applied to independent samples to assess the clinical relevance of results. We investigated consequences of structural differences on resting-state functional connectivity in cocaine addiction and tested whether resting-state functional connectivity of the identified circuits predict relapse in an independent cohort. Subjects included 64 non-treatment-seeking cocaine users (NTSCUs) and 67 healthy control subjects and an independent treatment-completed cohort (n = 45) of cocaine-dependent individuals scanned at the end of a 30-day residential treatment programme. Differences in cortical thickness and related resting-state functional connectivity between NTSCUs and healthy control subjects were identified. Survival analysis, applying cortical thickness of the identified regions, resting-state functional connectivity of the identified circuits and clinical characteristics to the treatment cohort, was used to predict relapse. Lower cortical thickness in bilateral insula and higher thickness in bilateral temporal pole were found in NTSCUs versus healthy control subjects. Whole brain resting-state functional connectivity analyses with these four different anatomical regions as seeds revealed eight weaker circuits including within the salience network (insula seeds) and between temporal pole and elements of the default mode network in NTSCUs. Applying these circuits and clinical characteristics to the independent cocaine-dependent treatment cohort, functional connectivity between right temporal pole and medial prefrontal cortex, combined with years of education, predicted relapse status at 150 days with 88% accuracy. Deficits in the salience network suggest an impaired ability to process

  3. Sexual transmissibility of HIV among opiate users with concurrent sexual partnerships: an egocentric network study in Yunnan, China.

    Science.gov (United States)

    Li, Jian; Liu, Hongjie; Li, Jianhua; Luo, Jian; Koram, Nana; Detels, Roger

    2011-10-01

    To investigate the patterns of concurrent sexual partnerships among young opiate users and sexual transmissibility of human immunodeficiency virus (HIV) in concurrent sexual partnerships in drug-use and sexual networks. Cross-sectional design. A total of 426 young opiate users in Yunnan, China. Young opiate users recruited from their network ties. Respondent-driven sampling (RDS) was used to recruit participants. Multiple logistic regressions were performed to analyze the relationships of concurrent sexual partnerships with egocentric social network components, risky sexual behavior for HIV and drug-use practices. The RDS-adjusted prevalence of concurrent sexual partners was 42.9% among opiate users. Opiate users with concurrent sexual partnerships were more likely to engage in risky HIV-related sexual behavior, compared to those without. Specifically, they were more likely to report having had four or more sexual partners (26.3% versus 2.0%), having had a spouse or boy/girlfriends who also had concurrent sexual partnerships (28.1% versus 8.2%), having exchanged drug for sex (12.4% versus 3.8%), having had sexual partners who were non-injection drug users (22.6% versus 10.1%), having had sexual partners who were injection drug users (25.3% versus 13.5%) and having used club drugs (26.3% versus 13.5%). There were no significant differences in consistent condom use between opiate users with sexual concurrency and those without. The same proportion (25.8%) of opiate users in the two groups reported having consistently used condoms when having sex with regular partners, and 46.3% of opiate users with sexual concurrency and 36.4% of those without such concurrency consistently used condoms with non-regular partners. The expansion of the human immunodeficiency virus epidemic from high-risk populations to the general population in China may be driven by concurrent sexual partnerships. Behavioral interventions targeting safer sex should be integrated into harm reduction

  4. 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.

  5. ACTS TDMA network control. [Advanced Communication Technology Satellite

    Science.gov (United States)

    Inukai, T.; Campanella, S. J.

    1984-01-01

    This paper presents basic network control concepts for the Advanced Communications Technology Satellite (ACTS) System. Two experimental systems, called the low-burst-rate and high-burst-rate systems, along with ACTS ground system features, are described. The network control issues addressed include frame structures, acquisition and synchronization procedures, coordinated station burst-time plan and satellite-time plan changes, on-board clock control based on ground drift measurements, rain fade control by means of adaptive forward-error-correction (FEC) coding and transmit power augmentation, and reassignment of channel capacities on demand. The NASA ground system, which includes a primary station, diversity station, and master control station, is also described.

  6. Distrubtion Tolerant Network Technology Flight Validation Report: DINET

    Science.gov (United States)

    Jones, Ross M.

    2009-01-01

    In October and November of 2008, the Jet Propulsion Laboratory installed and tested essential elements of Delay/Disruption Tolerant Networking (DTN) technology on the Deep Impact spacecraft. This experiment, called Deep Impact Network Experiment (DINET), was performed in close cooperation with the EPOXI project which has responsibility for the spacecraft. During DINET some 300 images were transmitted from the JPL nodes to the spacecraft. Then, they were automatically forwarded from the spacecraft back to the JPL nodes, exercising DTN's bundle origination, transmission, acquisition, dynamic route computation, congestion control, prioritization, custody transfer, and automatic retransmission procedures, both on the spacecraft and on the ground, over a period of 27 days. All transmitted bundles were successfully received, without corruption. The DINET experiment demonstrated DTN readiness for operational use in space missions.

  7. Distribution Tolerant Network Technology Flight Validation Report: DINET

    Science.gov (United States)

    Jones, Ross M.

    2009-01-01

    In October and November of 2008, the Jet Propulsion Laboratory installed and tested essential elements of Delay/Disruption Tolerant Networking (DTN) technology on the Deep Impact spacecraft. This experiment, called Deep Impact Network Experiment (DINET), was performed in close cooperation with the EPOXI project which has responsibility for the spacecraft. During DINET some 300 images were transmitted from the JPL nodes to the spacecraft. Then, they were automatically forwarded from the spacecraft back to the JPL nodes, exercising DTN's bundle origination, transmission, acquisition, dynamic route computation, congestion control, prioritization, custody transfer, and automatic retransmission procedures, both on the spacecraft and on the ground, over a period of 27 days. All transmitted bundles were successfully received, without corruption. The DINET experiment demonstrated DTN readiness for operational use in space missions.

  8. [Medical doctors driving technological innovation: questions about and innovation management approaches to incentive structures for lead users].

    Science.gov (United States)

    Bohnet-Joschko, Sabine; Kientzler, Fionn

    2010-01-01

    Management science defines user-generated innovations as open innovation and lead user innovation. The medical technology industry finds user-generated innovations profitable and even indispensable. Innovative medical doctors as lead users need medical technology innovations in order to improve patient care. Their motivation to innovate is mostly intrinsic. But innovations may also involve extrinsic motivators such as gain in reputation or monetary incentives. Medical doctors' innovative activities often take place in hospitals and are thus embedded into the hospital's organisational setting. Hospitals find it difficult to gain short-term profits from in-house generated innovations and sometimes hesitate to support them. Strategic investment in medical doctors' innovative activities may be profitable for hospitals in the long run if innovations provide first-mover competitive advantages. Industry co-operations with innovative medical doctors offer chances but also bear potential risks. Innovative ideas generated by expert users may result in even higher complexity of medical devices; this could cause mistakes when applied by less specialised users and thus affect patient safety. Innovations that yield benefits for patients, medical doctors, hospitals and the medical technology industry can be advanced by offering adequate support for knowledge transfer and co-operation models.

  9. Augmenting a TV Broadcast with Synchronised User Generated Video and Relevant Social Network Content

    NARCIS (Netherlands)

    Stokking, H.M.; Veenhuizen, A.T.; Kaptein, A.M.; Niamut, O.A.

    2014-01-01

    As TNO, we have developed an Augmented Live Broadcast use case, using components from the FP7 STEER project. In this use case, a television broadcast of a live event is augmented with user generated content. This user generated content consists of videos made by users at the event, and also of

  10. Social networking sites as business tool: a study of user behavior

    NARCIS (Netherlands)

    Constantinides, Efthymios; Lorenzo-Romero, C.; Alarcon-del-Amo, M.d.C.; Glykas, M.

    2013-01-01

    Social Networking Sites (SNS) are second generation web applications allowing the creation of personal online networks; the social networking domain has become one of the fastest growing online environments connecting hundreds of millions of people worldwide. Businesses are increasingly interested

  11. Technology and knowledge flow the power of networks

    CERN Document Server

    Trentin, Guglielmo

    2011-01-01

    This book outlines how network technology can support, foster and enhance the Knowledge Management, Sharing and Development (KMSD) processes in professional environments through the activation of both formal and informal knowledge flows. Understanding how ICT can be made available to such flows in the knowledge society is a factor that cannot be disregarded and is confirmed by the increasing interest of companies in new forms of software-mediated social interaction. The latter factor is in relation both to the possibility of accelerating internal communication and problem solving processes, an

  12. Emerging Topics in Internet Technology: A Complex Networks Approach

    OpenAIRE

    Khan, Bisma S.; Niazi, Muaz A.

    2017-01-01

    Communication networks, in general, and internet technology, in particular, is a fast-evolving area of research. While it is important to keep track of emerging trends in this domain, it is such a fast-growing area that it can be very difficult to keep track of literature. The problem is compounded by the fast-growing number of citation databases. While other databases are gradually indexing a large set of reliable content, currently the Web of Science represents one of the most highly valued...

  13. Wireless body area networks technology, implementation, and applications

    CERN Document Server

    Yuce, Mehmet R

    2011-01-01

    The book provides a comprehensive overview for the latest WBAN systems, technologies, and applications. The chapters of the book have been written by various specialists who are experts in their areas of research and practice. The book starts with the basic techniques involved in designing and building WBAN systems. It explains the deployment issues and then moves into the application areas of WBAN. The remaining chapters focus on the development of hardware, signal processing algorithms, and wireless communication and network design for wearable and implantable body sensors used in WBAN appli

  14. User Behavior Prediction based Adaptive Policy Pre-fetching Scheme for Efficient Network Management

    OpenAIRE

    Yuanlong Cao; Jianfeng Guan; Wei Quan; Jia Zhao; Changqiao Xu; Hongke Zhang

    2013-01-01

    In recent years, network management is commonly regarded as an essential and promising function for managing and improving the security of network infrastructures. However, as networks get faster and network centric applications get more complex, there is still significant ongoing work addressing many challenges of the network management. Traditional passive network censoring systems lack of adaptive policy pre-fetching scheme, as a result, preventing malicious behavior (such as hacker, malwa...

  15. Wearable Device Control Platform Technology for Network Application Development

    Directory of Open Access Journals (Sweden)

    Heejung Kim

    2016-01-01

    Full Text Available Application development platform is the most important environment in IT industry. There are a variety of platforms. Although the native development enables application to optimize, various languages and software development kits need to be acquired according to the device. The coexistence of smart devices and platforms has rendered the native development approach time and cost consuming. Cross-platform development emerged as a response to these issues. These platforms generate applications for multiple devices based on web languages. Nevertheless, development requires additional implementation based on a native language because of the coverage and functions of supported application programming interfaces (APIs. Wearable devices have recently attracted considerable attention. These devices only support Bluetooth-based interdevice communication, thereby making communication and device control impossible beyond a certain range. We propose Network Application Agent (NetApp-Agent in order to overcome issues. NetApp-Agent based on the Cordova is a wearable device control platform for the development of network applications, controls input/output functions of smartphones and wearable/IoT through the Cordova and Native API, and enables device control and information exchange by external users by offering a self-defined API. We confirmed the efficiency of the proposed platform through experiments and a qualitative assessment of its implementation.

  16. Utilizing HPC Network Technologies in High Energy Physics Experiments

    CERN Document Server

    AUTHOR|(CDS)2088631; The ATLAS collaboration

    2017-01-01

    Because of their performance characteristics high-performance fabrics like Infiniband or OmniPath are interesting technologies for many local area network applications, including data acquisition systems for high-energy physics experiments like the ATLAS experiment at CERN. This paper analyzes existing APIs for high-performance fabrics and evaluates their suitability for data acquisition systems in terms of performance and domain applicability. The study finds that existing software APIs for high-performance interconnects are focused on applications in high-performance computing with specific workloads and are not compatible with the requirements of data acquisition systems. To evaluate the use of high-performance interconnects in data acquisition systems a custom library, NetIO, is presented and compared against existing technologies. NetIO has a message queue-like interface which matches the ATLAS use case better than traditional HPC APIs like MPI. The architecture of NetIO is based on a interchangeable bac...

  17. Lipid Processing Technology: Building a Multilevel Modeling Network

    DEFF Research Database (Denmark)

    Díaz Tovar, Carlos Axel; Mustaffa, Azizul Azri; Mukkerikar, Amol

    2011-01-01

    of a master parameter table; iii) development of a model library consisting of new and adopted process models of unit operations involved in lipid processing technologies, validation of the developed models using operating data collected from existing process plants, and application of validated models......The aim of this work is to present the development of a computer aided multilevel modeling network for the systematic design and analysis of processes employing lipid technologies. This is achieved by decomposing the problem into four levels of modeling: i) pure component property modeling...... and a lipid-database of collected experimental data from industry and generated data from validated predictive property models, as well as modeling tools for fast adoption-analysis of property prediction models; ii) modeling of phase behavior of relevant lipid mixtures using the UNIFACCI model, development...

  18. The Asian Network for Education in Nuclear Technology (ANENT)

    International Nuclear Information System (INIS)

    Amin, F.; Grover, R.B.; Han, K.W.

    2004-01-01

    The per capita electricity availability in the Asian region is below the world average. Nuclear energy is considered by several countries in the region as a potential source to meet their growing energy demand. Thus, there is likely to be an expansion of nuclear power programme in the Asian region. Additionally, as the economies in the region expand, there will be an increasing role for isotope and radiation technologies in the health care, agriculture, and industrial sectors. The growing demand for power and non-power applications of nuclear technologies would require a sustainable supply of well-qualified nuclear workforce. The Asian Network for Education in Nuclear Technology, ANENT in short, was established in February 2004 in response to this need. The state of nuclear education in the region is at different levels in different countries. This diversity provides an opportunity for sharing of knowledge and resources. ANENT will facilitate cooperation in education, related research and training through: (i) sharing of information and materials on nuclear education and training; (ii) exchange of students, teachers and researchers; (iii) establishment of reference curricula and facilitating mutual recognition of degrees; and (iv) facilitating communication between ANENT member institutions and other regional and global networks. By focusing on education, ANENT complements existing activities undertaken by the International Atomic Energy Agency (IAEA) and supports IAEA activities for the preservation of nuclear knowledge. ANENT is a comprehensive initiative in education and training in that it will give equal importance to power and non-power technologies, thus meeting the diverse needs of the countries in the Asian region. (author)

  19. The use of social networking platforms for sexual health promotion: identifying key strategies for successful user engagement.

    Science.gov (United States)

    Veale, Hilary J; Sacks-Davis, Rachel; Weaver, Emma Rn; Pedrana, Alisa E; Stoové, Mark A; Hellard, Margaret E

    2015-02-06

    Online social networking platforms such as Facebook and Twitter have grown rapidly in popularity, with opportunities for interaction enhancing their health promotion potential. Such platforms are being used for sexual health promotion but with varying success in reaching and engaging users. We aimed to identify Facebook and Twitter profiles that were able to engage large numbers of users, and to identify strategies used to successfully attract and engage users in sexual health promotion on these platforms. We identified active Facebook (n = 60) and Twitter (n = 40) profiles undertaking sexual health promotion through a previous systematic review, and assessed profile activity over a one-month period. Quantitative measures of numbers of friends and followers (reach) and social media interactions were assessed, and composite scores used to give profiles an 'engagement success' ranking. Associations between host activity, reach and interaction metrics were explored. Content of the top ten ranked Facebook and Twitter profiles was analysed using a thematic framework and compared with five poorly performing profiles to identify strategies for successful user engagement. Profiles that were able to successfully engage large numbers of users were more active and had higher levels of interaction per user than lower-ranked profiles. Strategies used by the top ten ranked profiles included: making regular posts/tweets (median 46 posts or 124 tweets/month for top-ranked profiles versus six posts or six tweets for poorly-performing profiles); individualised interaction with users (85% of top-ranked profiles versus 0% for poorly-performing profiles); and encouraging interaction and conversation by posing questions (100% versus 40%). Uploading multimedia material (80% versus 30%) and highlighting celebrity involvement (70% versus 10%) were also key strategies. Successful online engagement on social networking platforms can be measured through quantitative (user numbers and

  20. Patients' perspectives on high-tech home care: a qualitative inquiry into the user-friendliness of four technologies.

    Science.gov (United States)

    Lehoux, Pascale

    2004-10-05

    The delivery of technology-enhanced home care is growing in most industrialized countries. The objective of our study was to document, from the patient's perspective, how the level of user-friendliness of medical technology influences its integration into the private and social lives of patients. Understanding what makes a technology user-friendly should help improve the design of home care services. Four home care interventions that are frequently used and vary in their technical and clinical features were selected: Antibiotic intravenous therapy, parenteral nutrition, peritoneal dialysis and oxygen therapy. Our qualitative study relied on the triangulation of three sources of data: 1) interviews with patients (n = 16); 2) interviews with carers (n = 6); and 3) direct observation of nursing visits of a different set of patients (n = 16). Participants of varying socioeconomic status were recruited through primary care organizations and hospitals that deliver home care within 100 km of Montreal, the largest urban area in the province of Quebec, Canada. The four interventions have both a negative and positive effect on patients' lives. These technologies were rarely perceived as user-friendly, and user-acceptance was closely linked to user-competence. Compared with acute I.V. patients, who tended to be passive, chronic patients seemed keener to master technical aspects. While some of the technical and human barriers were managed well in the home setting, engaging in the social world was more problematic. Most patients found it difficult to maintain a regular job because of the high frequency of treatment, while some carers found their autonomy and social lives restricted. Patients also tended to withdraw from social activities because of social stigmatization and technical barriers. While technology contributes to improving the patients' health, it also imposes significant constraints on their lives. Policies aimed at developing home care must clearly integrate

  1. Estimating the Theoretical Value for LAN Network Throughput Based Power Line Communications Technology Under the Homeplug 1.0 Standard

    Directory of Open Access Journals (Sweden)

    Martha Fabiola Contreras Higuera

    2013-06-01

    Full Text Available Power Line Communications (PLC refers to a group of technologies that allow to establish communication processes under the use of the grid as a physical means of transmission. The use of the grid as a physical means of transmission of information is not a new idea. Until a few years ago, the use of PLC had been limited to the implementation of solutions of control, automation and monitoring of sensors; which did not require a high bandwidth for its operation.During the late 1990s due to the new technological developments and the need to implement new alternatives for transfer of information, it was possible to reach speeds on the order of the Mbps, establishing the possibility of making use of the electricity network as a network of access. The current state of technology PLC allows to reach speeds of up to 200Mbps, which has enabled the transformation of the grid in a true network of band wide, capable of supporting data, voice and video provided by a telecommunications operator. The use of PLC-based network adapters allow easily design LANs and broadband communications through the electrical network, making any outlet in a point of connection for the user, without the need for wiring additional to existing ones.  The electrical network is a structure which so far has been exclusively used for the transport of electrical energy. However, it is possible to make use of this network in processes of communication and transmission of information such as: voice, data and video; Bearing in mind that grid had not been designed for this purpose. The performance is without doubt one of the aspects of greatest interest in the global analysis in networks LAN, due to the effect it produces on the end user. Basically, the most common parameters for evaluating the performance of a network are: Throughput, use of the canal and various measures of retardation. In this article is presented a simple analysis of the HomePlug 1.0 standard applied to the

  2. New Technologies to Reclaim Arid Lands User's Manual

    Energy Technology Data Exchange (ETDEWEB)

    W. K. Ostler

    2002-10-01

    Approximately 70 percent of all U.S. military training lands are located in arid and semi-arid areas. Training activities in such areas frequently adversely affect vegetation, damaging plants and reducing the resilience of vegetation to recover once disturbed. Fugitive dust resulting from a loss of vegetation creates additional problems for human health, increasing accidents due to decreased visibility, and increasing maintenance costs for roads, vehicles, and equipment. Under conventional technologies to mitigate these impacts, it is estimated that up to 35 percent of revegetation projects in arid areas will fail due to unpredictable natural environmental conditions, such as drought, and reclamation techniques that were inadequate to restore vegetative cover in a timely and cost-effective manner. New reclamation and restoration techniques are needed in desert ranges to help mitigate the adverse effects of military training and other activities to arid-land environments. In 1999, a cooperative effort between the U.S. Department of Energy (DOE), the US. Department of Defense (DoD), and selected university scientists was undertaken to focus on mitigating military impacts in arid lands. As arid lands are impacted due to DoD and DOE activities, biological and soil resources are gradually lost and the habitat is altered. A conceptual model of that change in habitat quality is described for varying levels of disturbance in the Mojave Desert. As the habitat quality degrades and more biological and physical resources are lost from training areas, greater costs are required to return the land to sustainable levels. The purpose of this manual is to assist land managers in recognizing thresholds associated with habitat degradation and provide reclamation planning and techniques that can reduce the costs of mitigation for these impacted lands to ensure sustainable use of these lands. The importance of reclamation planning is described in this manual with suggestions about

  3. The importance of social networks in their association to drug equipment sharing among injection drug users: a review.

    Science.gov (United States)

    De, Prithwish; Cox, Joseph; Boivin, Jean-François; Platt, Robert W; Jolly, Ann M

    2007-11-01

    To examine the scientific evidence regarding the association between characteristics of social networks of injection drug users (IDUs) and the sharing of drug injection equipment. A search was performed on MEDLINE, EMBASE, BIOSIS, Current Contents, PsycINFO databases and other sources to identify published studies on social networks of IDUs. Papers were selected based on their examination of social network factors in relation to the sharing of syringes and drug preparation equipment (e.g. containers, filters, water). Additional relevant papers were found from the reference list of identified articles. Network correlates of drug equipment sharing are multi-factorial and include structural factors (network size, density, position, turnover), compositional factors (network member characteristics, role and quality of relationships with members) and behavioural factors (injecting norms, patterns of drug use, severity of drug addiction). Factors appear to be related differentially to equipment sharing. Social network characteristics are associated with drug injection risk behaviours and should be considered alongside personal risk behaviours in prevention programmes. Recommendations for future research into the social networks of IDUs are proposed.

  4. How user diversity and country of origin impact the readiness to adopt E-health technologies: an intercultural comparison.

    Science.gov (United States)

    Wilkowsk, Wiktoria; Ziefle, Martina; Alagöz, Firat

    2012-01-01

    In recent years, due to the demographical change and the resulting overload of healthcare systems, there has been an increasing interest focusing on the global proliferation of assistive medical technologies (=E-health) in home environments. The present study examines how users' diversity influences the readiness to adopt novel medical technologies, comparing users' attitudes in terms of perceived advantages and disadvantages in three technically and culturally different countries: Germany, Poland and Turkey. This investigation also intended to verify if acceptance of information and communication technologies is associated with the sensitive acceptance of E-health. Results revealed overall a considerably higher motivation to use medical technology compared to perceived barriers, with Polish users more willing to use E-health, higher than German or Turkish ones. Older participants showed a highly positive attitude, comparable to young and middle-aged respondents' receptiveness, differing from the latter in terms of greater appreciation of the advantage of higher independency when being supported by medical technology. With respect to gender, woman showed higher motivation to use E-health technology than men, although utilization barriers were not gendered. Following these results, an unconditional transfer of acceptance from information and communication to medical technology is not justified.

  5. Security-Reliability Trade-Off Analysis for Multiuser SIMO Mixed RF/FSO Relay Networks With Opportunistic User Scheduling

    KAUST Repository

    El-Malek, Ahmed H. Abd

    2016-05-24

    In this paper, we study the performance of multiuser single-input multiple-output mixed radio frequency (RF)/free space optical (FSO) relay network with opportunistic user scheduling. The considered system includes multiple users, one amplify-and-forward relay, one destination, and a multiple-antenna eavesdropper. The users are connected with the relay node through RF links and the relay is connected with the destination through an FSO link. Both maximum ratio combining and selection combining schemes are used at the multiple-antenna relay to combine the signal received from the best user on different antennas. The RF/FSO channels models are assumed to follow Nakagami-m/gamma-gamma fading models with pointing errors. Closed-form expressions are derived for the outage probability, average symbol error probability, and ergodic channel capacity. Then, the power of the selected best user is determined to minimize the system asymptotic outage probability under the dominant RF or FSO link. Then, the considered system secrecy performance is investigated, where the closed-form expressions for the intercept probability are derived. Finally, we propose a new cooperative jamming model in which the worst user is selected by the authorized system to jam the existing eavesdropper. Monte-Carlo simulations are provided to validate the achieved exact and asymptotic results.

  6. Fuzzy Extractor and Elliptic Curve Based Efficient User Authentication Protocol for Wireless Sensor Networks and Internet of Things

    Directory of Open Access Journals (Sweden)

    Anup Kumar Maurya

    2017-10-01

    Full Text Available To improve the quality of service and reduce the possibility of security attacks, a secure and efficient user authentication mechanism is required for Wireless Sensor Networks (WSNs and the Internet of Things (IoT. Session key establishment between the sensor node and the user is also required for secure communication. In this paper, we perform the security analysis of A.K.Das’s user authentication scheme (given in 2015, Choi et al.’s scheme (given in 2016, and Park et al.’s scheme (given in 2016. The security analysis shows that their schemes are vulnerable to various attacks like user impersonation attack, sensor node impersonation attack and attacks based on legitimate users. Based on the cryptanalysis of these existing protocols, we propose a secure and efficient authenticated session key establishment protocol which ensures various security features and overcomes the drawbacks of existing protocols. The formal and informal security analysis indicates that the proposed protocol withstands the various security vulnerabilities involved in WSNs. The automated validation using AVISPA and Scyther tool ensures the absence of security attacks in our scheme. The logical verification using the Burrows-Abadi-Needham (BAN logic confirms the correctness of the proposed protocol. Finally, the comparative analysis based on computational overhead and security features of other existing protocol indicate that the proposed user authentication system is secure and efficient. In future, we intend to implement the proposed protocol in real-world applications of WSNs and IoT.

  7. Social network influences on technology acceptance : A matter of tie strength, centrality and density

    NARCIS (Netherlands)

    Ten Kate, Stephan; Haverkamp, Sophie; Mahmood, Fariha; Feldberg, Frans

    2010-01-01

    This study examines social network influences on the individual technology acceptance. Since it is believed that individuals' trust, opinions and behavior are influenced by their network, an analysis of that network may help to provide some explanations on technology acceptance. However, since

  8. Non-Contact Plant Growth Measurement Method and System Based on Ubiquitous Sensor Network Technologies

    Directory of Open Access Journals (Sweden)

    Intae Ryoo

    2011-04-01

    Full Text Available This paper proposes a non-contact plant growth measurement system using infrared sensors based on the ubiquitous sensor network (USN technology. The proposed system measures plant growth parameters such as the stem radius of plants using real-time non-contact methods, and generates diameter, cross-sectional area and thickening form of plant stems using this measured data. Non-contact sensors have been used not to cause any damage to plants during measurement of the growth parameters. Once the growth parameters are measured, they are transmitted to a remote server using the sensor network technology and analyzed in the application program server. The analyzed data are then provided for administrators and a group of interested users. The proposed plant growth measurement system has been designed and implemented using fixed-type and rotary-type infrared sensor based measurement methods and devices. Finally, the system performance is compared and verified with the measurement data that have been obtained by practical field experiments.

  9. Two-user opportunistic scheduling using hierarchical modulations in wireless networks with heterogenous average link gains

    KAUST Repository

    Hossain, Md Jahangir

    2010-03-01

    Our contribution, in this paper, is two-fold. First, we analyze the performance of a hierarchical modulation-assisted two-best user opportunistic scheduling (TBS) scheme, which was proposed by the authors, in a fading environment where different users have different average link gains. Specifically, we present a new expression for the spectral efficiency (SE) of the users and using this expression, we compare the degrees of fairness (DOF) of the TBS scheme with that of classical single user opportunistic scheduling schemes, namely, absolute carrier-to-noise ratio (CNR) based single-best user scheduling (SBS) and normalized CNR based proportional fair scheduling (PFS) schemes. The second contribution is that we propose a new hybrid two-user opportunistic scheduling (HTS) scheme based on our earlier proposed TBS scheme. This HTS scheme selects the first user based on the largest absolute CNR value among all the users while the second user is selected based on the ratios of the absolute CNRs to the corresponding average CNRs of the remaining users. The total transmission rate i.e., the constellation size is selected according to the absolute CNR of the first best user. The total transmission rate is then allocated among these selected users by joint consideration of their absolute CNRs and allocated number of information bit(s) are transmitted to them using hierarchical modulations. Numerical results are presented for a fading environment where different users experience independent but non-identical (i.n.d.) channel fading. These selected numerical results show that the proposed HTS scheme can considerably increase the system\\'s fairness without any degradation of the link spectral efficiency (LSE) i.e., the multiuser diversity gain compared to the classical SBS scheme. These results also show that the proposed HTS scheme has a lower fairness in comparison to the PFS scheme which suffers from a considerable degradation in LSE. © 2010 IEEE.

  10. Usability Issues in the User Interfaces of Privacy-Enhancing Technologies

    Science.gov (United States)

    LaTouche, Lerone W.

    2013-01-01

    Privacy on the Internet has become one of the leading concerns for Internet users. These users are not wrong in their concerns if personally identifiable information is not protected and under their control. To minimize the collection of Internet users' personal information and help solve the problem of online privacy, a number of…

  11. User Acceptance of Long-Term Evolution (LTE) Services: An Application of Extended Technology Acceptance Model

    Science.gov (United States)

    Park, Eunil; Kim, Ki Joon

    2013-01-01

    Purpose: The aim of this paper is to propose an integrated path model in order to explore user acceptance of long-term evolution (LTE) services by examining potential causal relationships between key psychological factors and user intention to use the services. Design/methodology/approach: Online survey data collected from 1,344 users are analysed…

  12. Recon2Neo4j: applying graph database technologies for managing comprehensive genome-scale networks.

    Science.gov (United States)

    Balaur, Irina; Mazein, Alexander; Saqi, Mansoor; Lysenko, Artem; Rawlings, Christopher J; Auffray, Charles

    2017-04-01

    The goal of this work is to offer a computational framework for exploring data from the Recon2 human metabolic reconstruction model. Advanced user access features have been developed using the Neo4j graph database technology and this paper describes key features such as efficient management of the network data, examples of the network querying for addressing particular tasks, and how query results are converted back to the Systems Biology Markup Language (SBML) standard format. The Neo4j-based metabolic framework facilitates exploration of highly connected and comprehensive human metabolic data and identification of metabolic subnetworks of interest. A Java-based parser component has been developed to convert query results (available in the JSON format) into SBML and SIF formats in order to facilitate further results exploration, enhancement or network sharing. The Neo4j-based metabolic framework is freely available from: https://diseaseknowledgebase.etriks.org/metabolic/browser/ . The java code files developed for this work are available from the following url: https://github.com/ibalaur/MetabolicFramework . ibalaur@eisbm.org. Supplementary data are available at Bioinformatics online.

  13. Devices for visually impaired people: High technological devices with low user acceptance and no adaptability for children.

    Science.gov (United States)

    Gori, Monica; Cappagli, Giulia; Tonelli, Alessia; Baud-Bovy, Gabriel; Finocchietti, Sara

    2016-10-01

    Considering that cortical plasticity is maximal in the child, why are the majority of technological devices available for visually impaired users meant for adults and not for children? Moreover, despite high technological advancements in recent years, why is there still no full user acceptance of existing sensory substitution devices? The goal of this review is to create a link between neuroscientists and engineers by opening a discussion about the direction that the development of technological devices for visually impaired people is taking. Firstly, we review works on spatial and social skills in children with visual impairments, showing that lack of vision is associated with other sensory and motor delays. Secondly, we present some of the technological solutions developed to date for visually impaired people. Doing this, we highlight the core features of these systems and discuss their limits. We also discuss the possible reasons behind the low adaptability in children. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  14. User localization in complex environments by multimodal combination of GPS, WiFi, RFID, and pedometer technologies.

    Science.gov (United States)

    Dao, Trung-Kien; Nguyen, Hung-Long; Pham, Thanh-Thuy; Castelli, Eric; Nguyen, Viet-Tung; Nguyen, Dinh-Van

    2014-01-01

    Many user localization technologies and methods have been proposed for either indoor or outdoor environments. However, each technology has its own drawbacks. Recently, many researches and designs have been proposed to build a combination of multiple localization technologies system which can provide higher precision results and solve the limitation in each localization technology alone. In this paper, a conceptual design of a general localization platform using combination of multiple localization technologies is introduced. The combination is realized by dividing spaces into grid points. To demonstrate this platform, a system with GPS, RFID, WiFi, and pedometer technologies is established. Experiment results show that the accuracy and availability are improved in comparison with each technology individually.

  15. A Web-based Multi-user Interactive Visualization System For Large-Scale Computing Using Google Web Toolkit Technology

    Science.gov (United States)

    Weiss, R. M.; McLane, J. C.; Yuen, D. A.; Wang, S.

    2009-12-01

    We have created a web-based, interactive system for multi-user collaborative visualization of large data sets (on the order of terabytes) that allows users in geographically disparate locations to simultaneous and collectively visualize large data sets over the Internet. By leveraging asynchronous java and XML (AJAX) web development paradigms via the Google Web Toolkit (http://code.google.com/webtoolkit/), we are able to provide remote, web-based users a web portal to LCSE's (http://www.lcse.umn.edu) large-scale interactive visualization system already in place at the University of Minnesota that provides high resolution visualizations to the order of 15 million pixels by Megan Damon. In the current version of our software, we have implemented a new, highly extensible back-end framework built around HTTP "server push" technology to provide a rich collaborative environment and a smooth end-user experience. Furthermore, the web application is accessible via a variety of devices including netbooks, iPhones, and other web- and javascript-enabled cell phones. New features in the current version include: the ability for (1) users to launch multiple visualizations, (2) a user to invite one or more other users to view their visualization in real-time (multiple observers), (3) users to delegate control aspects of the visualization to others (multiple controllers) , and (4) engage in collaborative chat and instant messaging with other users within the user interface of the web application. We will explain choices made regarding implementation, overall system architecture and method of operation, and the benefits of an extensible, modular design. We will also discuss future goals, features, and our plans for increasing scalability of the system which includes a discussion of the benefits potentially afforded us by a migration of server-side components to the Google Application Engine (http://code.google.com/appengine/).

  16. Wireless sensor networks for applied research on rain-fed farming in India: an exploratory user experiment

    OpenAIRE

    Panchard, Jacques; Rao, Seshagiri; Sheshshayee, S.

    2008-01-01

    This document describes a user experiment that was conducted between October 2007 and February 2008 around a wireless sensor network for rain-fed agriculture. The experiment was organized jointly by UAS, the CK Trust and the EPFL. The participants came from an Indian university of agriculture, an Indian non-governmental organization active in rain-fed farming sustainability, and the Kanrnataka department of agriculture.

  17. Designing 3ERP to meet use and users - methods to handle cultural diversity and collaborative networking in SMEs

    DEFF Research Database (Denmark)

    Dirckinck-Holmfeld, Lone; Nielsen, Janni

    2007-01-01

    The purpose is to describe a project the aim of which is to develop and validate the scientific methodological foundation for design of user friendly and usable, flexible and configurable global Enterprise Resource Planning system for Small and Medium sized Enterprises (SMEs) which are adoptable ...... to cultural diversity and support the collaborative networking tasks embedded in 3gERP. Focus is on Human Centered Design methods and tools which must be developed to handle cultural diversity....

  18. End-user satisfaction analysis on library management system unnes using technology acceptance model towards national standard of integrated library

    Science.gov (United States)

    Hardyanto, W.; Purwinarko, A.; Adhi, M. A.

    2018-03-01

    The library which is the gate of the University should be supported by the existence of an adequate information system, to provide excellent service and optimal to every user. Library management system that has been in existence since 2009 needs to be re-evaluated so that the system can meet the needs of both operator and Unnes user in particular, and users from outside Unnes in general. This study aims to evaluate and improve the existing library management system to produce a system that is accountable and able to meet the needs of end users, as well as produce a library management system that is integrated Unnes. Research is directed to produce evaluation report with Technology Acceptance Model (TAM) approach and library management system integrated with the national standard.

  19. User Management with LDAP(Light weight Directory Access Protocolfor access to technology and Information Services in Companies

    Directory of Open Access Journals (Sweden)

    José Teodoro Mejía Viteri

    2016-08-01

    Full Text Available This research aims to conduct an analysis of management services information and users with LDAP (Lightweight / Simplified Directory Access Protocol, their interaction with other technology services company, allowing it to be accessed through a single user and password. This study allowed us to collect information through a literature review on the LDAP service and its ability to interact with your user directory Open source technology services; also with Windows Server and Active Directory service is used by companies for their ease of management and access resources on Windows clients; is intended to provide an alternative for the implementation of each of the services required by public and private companies with tools free use and access to services for management and administration can be done by integrating or synchronizing with the directory LDAP.

  20. Social Networks As Internet-technologies in Electoral Campaigns: the International View

    Directory of Open Access Journals (Sweden)

    Александр Александрович Свинин

    2013-12-01

    Full Text Available Social networks as internet-technologies became a useful instrument for politicians during the electoral campaigns. The main reason for that is the fact that social networks today are the next step in development of communications between people. In the article the author investigates the history of social networks, different cases of application of social networks in electoral campaigns.