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. A Distributed Algorithm for Fair and Efficient User-Network Association in Multi-Technology Wireless Networks

    CERN Document Server

    Touati, Corinne; Gaujal, Bruno

    2008-01-01

    Recent mobile equipment (as well as the norm IEEE 802.21) now offers the possibility for users to switch from one technology to another (vertical handover). This allows flexibility in resource assignments and, consequently, increases the potential throughput allocated to each user. In this paper, we design a fully distributed algorithm based on trial and error mechanisms that exploits the benefits of vertical handover by finding fair and efficient assignment schemes. On the one hand, mobiles gradually update the fraction of data packets they send to each network based on the rewards they receive from the stations. On the other hand, network stations send rewards to each mobile that represent the impact each mobile has on the cell throughput. This reward function is closely related to the concept of marginal cost in the pricing literature. Both the station and the mobile algorithms are simple enough to be implemented in current standard equipment. Based on tools from evolutionary games, potential games and rep...

  3. User programmable virtualized networks

    NARCIS (Netherlands)

    Meijer, R.J.; Strijkers, R.J.; Gommans, L.; Laat, C.de

    2006-01-01

    This paper introduces the concept of a User Programmable Virtualized Network, which allows networks to deliver application specific services using network element components that developers can program as part of a users application. The use of special tokens in data or control packets is the basis

  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. 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

  6. Network user`s guide

    Energy Technology Data Exchange (ETDEWEB)

    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.

  7. 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

  8. 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.

  9. 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.

  10. 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

  11. 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.

  12. 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.

  13. 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…

  14. Recognizing Multi-user Activities using Body Sensor Networks

    DEFF Research Database (Denmark)

    Gu, Tao; Wang, Liang; Chen, Hanhua

    2011-01-01

    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...... 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...... 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...

  15. Distributed Bayesian Networks for User Modeling

    DEFF Research Database (Denmark)

    Tedesco, Roberto; Dolog, Peter; Nejdl, Wolfgang

    2006-01-01

    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...... efficiently combines distributed learner models without the need to exchange internal structure of local Bayesian networks, nor local evidence between the involved platforms....

  16. 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.

  17. 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......-site processes. On the other hand generic technologies are also widely implemented in routine and day-today activities, making mobile technologies in construction a mix of user and technology driven innovations....

  18. 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 ex

  19. Segmentation of users of social networking websites

    NARCIS (Netherlands)

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

    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 ex

  20. Users speak out on technology deployment

    Energy Technology Data Exchange (ETDEWEB)

    Peters, Mark; Prochaska, Marty; Cromer, Paul; Zewatsky, Jennifer

    2001-02-25

    This report summarizes user feedback data collected during a recent Accelerated Site Technology Deployment (ASTD) project: the Fluor Fernald ASTD Technology Deployment Project from May, 1999 through September, 2000. The main goal of the ASTD project was to use the ''Fernald approach'' to expedite the deployment of new or innovative technologies with superior safety, cost, and/or productivity benefits to Department of Energy (DOE) facilities. The Fernald approach targets technology end-users and their managers and directly involves them with hands-on demonstrations of new or innovative technologies during technology transfer sessions. The two technologies deployed through this project were the Personal Ice Cooling System (PICS) and the oxy-gasoline torch. Participants of technology transfer sessions were requested to complete feedback surveys. Surveys evaluated the effectiveness of the Fernald approach to technology deployment and assessed the responsiveness of employees to new technologies. This report presents the results of those surveys.

  1. Podcast search: user goals and retrieval technologies

    NARCIS (Netherlands)

    Besser, J.; Larson, M.; Hofmann, K.

    2010-01-01

    Purpose - This research aims to identify users' goals and strategies when searching for podcasts and their impact on the design of podcast retrieval technology. In particular, the paper seeks to explore the potential to address user goals with indexing based on podcast metadata and automatic speech

  2. Podcast search: user goals and retrieval technologies

    NARCIS (Netherlands)

    Besser, J.; Larson, M.; Hofmann, K.

    2010-01-01

    Purpose - This research aims to identify users' goals and strategies when searching for podcasts and their impact on the design of podcast retrieval technology. In particular, the paper seeks to explore the potential to address user goals with indexing based on podcast metadata and automatic speech

  3. LTE mobile network technology

    OpenAIRE

    Sladič, Klemen

    2012-01-01

    The main purpose of this thesis is an introduction to long term evolution of fourth generation mobile networks based on LTE mobile network standard. Fourth generation mobile networks are currently one of the most developed technology in the world of mobile communications and are somewhere already available for commercial use. At the beginning is a short history of mobile networks evolution, for easier understanding. In the history you can find information from first researches of magnetic...

  4. 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......-based services and possibly becoming service providers themselves. This is already happening in the so-called "social networks" and peer-to-peer file sharing networks on the Internet - making this emerging topic one of the most active research areas in the wireless communications filed....

  5. 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

  6. Classifying user states in next generation networks

    Science.gov (United States)

    He, Y.; Bilgic, A.

    2011-08-01

    In this paper we apply a classification method to learn geographic regions using Location Based Services (LBS) in IP Multimedia Subsystem (IMS). We assume that the information in Local Network (cellular network) can be freely exchanged with Global IP Network (IMS) and the information can be gathered in a data base. LBS in the IMS also provide location information for the data sets. Statistic classification methods are applied to the data sets in the data base. Depending on the information provided by the users, they are divided into different user groups (event classes) using Type Filters (TF). Then discriminant analysis is applied to the position information offered by LBS in IMS to determine the geographic regions of the different classes. The learned geographic regions can be used to inform the users in this region or other regions over IMS. This kind of service can be used for any location-based events.

  7. Analysis of user profile in social networks

    OpenAIRE

    Rodrigues, Adão Carlos Fernandes

    2013-01-01

    Dissertação de mestrado em Engenharia de Informática With this work it is intended to create / identify user profiles through their actions on social networks. This identification is to determine, in a specific way, which profile each user has, linking between the following dimensions and their sets of variables: sociodemographic characteristics (gender, age, education, situation before the economic activity indicator and occupational class) the specific type of aggregate practices cond...

  8. Networks and emotion-driven user communities at popular blogs

    Science.gov (United States)

    Mitrović, M.; Paltoglou, G.; Tadić, B.

    2010-10-01

    Online communications at web portals represents technology-mediated user interactions, leading to massive data and potentially new techno-social phenomena not seen in real social mixing. Apart from being dynamically driven, the user interactions via posts is indirect, suggesting the importance of the contents of the posted material. We present a systematic way to study Blog data by combined approaches of physics of complex networks and computer science methods of text analysis. We are mapping the Blog data onto a bipartite network where users and posts with comments are two natural partitions. With the machine learning methods we classify the texts of posts and comments for their emotional contents as positive or negative, or otherwise objective (neutral). Using the spectral methods of weighted bipartite graphs, we identify topological communities featuring the users clustered around certain popular posts, and underly the role of emotional contents in the emergence and evolution of these communities.

  9. 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...

  10. 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.

  11. Creating Profiles from User Network Behavior

    Science.gov (United States)

    2013-09-01

    might reveal unique markers for user network activity. The A records are used to obtain IPv4 addresses, and AAAA records are for IPv6 addresses. A TXT...Meaning A 1 (IPv4) host address MX 15 mail exchange TXT 16 text strings SRV 33 server selection AAAA 28 ( IPv6 ) host address Table 3.3: TYPE, value...J. of Wireless Mobile Networks, Ubiquitous Computing, and Dependable Applicat. (JoWUA), vol. 3, no. 4, pp. 4–20, Dec. 2012. [13] A. Cummings and R

  12. Modelling Users` Trust in Online Social Networks

    Directory of Open Access Journals (Sweden)

    Iacob Cătoiu

    2014-02-01

    Full Text Available Previous studies (McKnight, Lankton and Tripp, 2011; Liao, Lui and Chen, 2011 have shown the crucial role of trust when choosing to disclose sensitive information online. This is the case of online social networks users, who must disclose a certain amount of personal data in order to gain access to these online services. Taking into account privacy calculus model and the risk/benefit ratio, we propose a model of users’ trust in online social networks with four variables. We have adapted metrics for the purpose of our study and we have assessed their reliability and validity. We use a Partial Least Squares (PLS based structural equation modelling analysis, which validated all our initial assumptions, indicating that our three predictors (privacy concerns, perceived benefits and perceived risks explain 48% of the variation of users’ trust in online social networks, the resulting variable of our study. We also discuss the implications and further research opportunities of our study.

  13. 网络文化建设视角下的网络安全管理探析%User-based Internal Network Information Security Technology and Management Research

    Institute of Scientific and Technical Information of China (English)

    樊梦

    2012-01-01

    With the application of network technology becomes more extensive,network security has become increasingly serious practical problems,and internal network security issues are more prominent,has been a serious threat and affect the normal use within the network,must pass on the user and device identity management,data management,rights management,process management,customer management,as well as several aspects of system management,technology and the organic integration of the system to ensure that the internal network safe and efficient operation.%随着互联网的高速发展,网络文化也蓬勃兴起并深刻影响着网络安全管理。本文通过在对网络文化的概念阐述的基础上,进一步分析了网络文化产生的负面影响,从而提出了网络文化建设与网络安全管理的相关对策。

  14. 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.

  15. 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.

  16. 75 FR 63253 - State-56, Network User Account Records

    Science.gov (United States)

    2010-10-14

    ... a Department network; to monitor security of computer systems; to investigate and make referrals for...: Network User Account Records. SECURITY CLASSIFICATION: Unclassified. SYSTEM LOCATION: Records are..., Network User Account Records SUMMARY: Notice is hereby given that the Department of State proposes...

  17. 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...

  18. BP Network Based Users' Interest Model in Mining WWW Cache

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    By analyzing the WWW Cache model, we bring forward a user-interest description method based on the fuzzy theory and user-interest inferential relations based on BP(back propagation) neural network. By this method, the users' interest in the WWW cache can be described and the neural network of users' interest can be constructed by positive spread of interest and the negative spread of errors. This neural network can infer the users' interest. This model is not the simple extension of the simple interest model, but the round improvement of the model and its related algorithm.

  19. Approaches for user profile Investigation in Orkut Social Network

    CERN Document Server

    Singh, Rajni Ranjan

    2009-01-01

    Internet becomes a large and rich repository of information about us as individually. Any thing form user profile information to friends links the user subscribes to are reflection of social interactions as user has in real worlds. Social networking has created new ways to communicate and share information. Social networking websites are being used regularly by millions of people, and it now seems that social networking will be an enduring part of everyday life. Social networks such as Orkut, Bebo, MySpace, Flickr, Facebook, Friendster and LinkedIn, have attracted millions of internet user who are involved in bogging, participatory book reviewing, personal networking and photo sharing. Social network services are increasingly being used in legal and criminal investigations. Information posted on sites such as Orkut and Facebook has been used by police, probation, and university officials to prosecute users of said sites. In some situations, content posted on web social network has been used in court. In the p...

  20. Distributed Observer Network (DON), Version 3.0, User's Guide

    Science.gov (United States)

    Mazzone, Rebecca A.; Conroy, Michael P.

    2015-01-01

    The Distributed Observer Network (DON) is a data presentation tool developed by the National Aeronautics and Space Administration (NASA) to distribute and publish simulation results. Leveraging the display capabilities inherent in modern gaming technology, DON places users in a fully navigable 3-D environment containing graphical models and allows the users to observe how those models evolve and interact over time in a given scenario. Each scenario is driven with data that has been generated by authoritative NASA simulation tools and exported in accordance with a published data interface specification. This decoupling of the data from the source tool enables DON to faithfully display a simulator's results and ensure that every simulation stakeholder will view the exact same information every time.

  1. 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.

  2. Scaled CMOS Technology Reliability Users Guide

    Science.gov (United States)

    White, Mark

    2010-01-01

    The desire to assess the reliability of emerging scaled microelectronics technologies through faster reliability trials and more accurate acceleration models is the precursor for further research and experimentation in this relevant field. The effect of semiconductor scaling on microelectronics product reliability is an important aspect to the high reliability application user. From the perspective of a customer or user, who in many cases must deal with very limited, if any, manufacturer's reliability data to assess the product for a highly-reliable application, product-level testing is critical in the characterization and reliability assessment of advanced nanometer semiconductor scaling effects on microelectronics reliability. A methodology on how to accomplish this and techniques for deriving the expected product-level reliability on commercial memory products are provided.Competing mechanism theory and the multiple failure mechanism model are applied to the experimental results of scaled SDRAM products. Accelerated stress testing at multiple conditions is applied at the product level of several scaled memory products to assess the performance degradation and product reliability. Acceleration models are derived for each case. For several scaled SDRAM products, retention time degradation is studied and two distinct soft error populations are observed with each technology generation: early breakdown, characterized by randomly distributed weak bits with Weibull slope (beta)=1, and a main population breakdown with an increasing failure rate. Retention time soft error rates are calculated and a multiple failure mechanism acceleration model with parameters is derived for each technology. Defect densities are calculated and reflect a decreasing trend in the percentage of random defective bits for each successive product generation. A normalized soft error failure rate of the memory data retention time in FIT/Gb and FIT/cm2 for several scaled SDRAM generations is

  3. 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.

  4. 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

    2016-01-01

    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. PMID:27355951

  5. A Survey of 5G Network: Architecture and Emerging Technologies

    National Research Council Canada - National Science Library

    Gupta, A; Jha, R. K

    2015-01-01

    .... This paper presents the results of a detailed survey on the fifth generation (5G) cellular network architecture and some of the key emerging technologies that are helpful in improving the architecture and meeting the demands of users...

  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. AD SHARING IN SOCIAL NETWORKS : ROLE OF USER DEFINED POLICIES

    Directory of Open Access Journals (Sweden)

    Venkata N Inukollu

    2014-09-01

    Full Text Available Security policies describe the demeanor of a system through specific rules and are becoming an increasingly popular approach for static and dynamic environment applications.Online social networks have become a de facto portal for Internet access for millions of users. Users share different content on social media sometimes which includes personal information.However, users entrust the social network providers with such personal information.Although social networking sites offer privacy controls, the sites provide insufficient controls to restrict data sharing and let users restrict how their data is handled and viewed by other users.To match the privacy demands of an online social network user, we have suggested a new security policy and have tested the policy successfully on various levels

  8. 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...

  9. Research on Bayesian Network Based User's Interest Model

    Institute of Scientific and Technical Information of China (English)

    ZHANG Weifeng; XU Baowen; CUI Zifeng; XU Lei

    2007-01-01

    It has very realistic significance for improving the quality of users' accessing information to filter and selectively retrieve the large number of information on the Internet. On the basis of analyzing the existing users' interest models and some basic questions of users' interest (representation, derivation and identification of users' interest), a Bayesian network based users' interest model is given. In this model, the users' interest reduction algorithm based on Markov Blanket model is used to reduce the interest noise, and then users' interested and not interested documents are used to train the Bayesian network. Compared to the simple model, this model has the following advantages like small space requirements, simple reasoning method and high recognition rate. The experiment result shows this model can more appropriately reflect the user's interest, and has higher performance and good usability.

  10. A social network perspective of lead users and creativity

    DEFF Research Database (Denmark)

    Kratzer, Jan; Lettl, Christopher

    2008-01-01

    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...

  11. Technology User Groups and Early Childhood Education: A Preliminary Study

    Science.gov (United States)

    Parette, Howard P.; Hourcade, Jack J.; Blum, Craig; Watts, Emily H.; Stoner, Julia B.; Wojcik, Brian W.; Chrismore, Shannon B.

    2013-01-01

    This article presents a preliminary examination of the potential of Technology User Groups as a professional development venue for early childhood education professionals in developing operational and functional competence in using hardware and software components of a Technology toolkit. Technology user groups are composed of varying numbers of…

  12. 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!

  13. User Association for Load Balancing in Heterogeneous Cellular Networks

    CERN Document Server

    Ye, Qiaoyang; Chen, Yudong; Al-Shalash, Mazin; Caramanis, Constantine; Andrews, Jeffrey G

    2012-01-01

    For small cell technology to significantly increase the capacity of tower-based cellular networks, mobile users will need to be actively pushed onto the more lightly loaded tiers (corresponding to, e.g., pico and femtocells), even if they offer a lower instantaneous SINR than the macrocell base station (BS). Optimizing a function of the long-term rates for each user requires (in general) a massive utility maximization problem over all the SINRs and BS loads. On the other hand, an actual implementation will likely resort to a simple biasing approach where a BS in tier j is treated as having its SINR multiplied by a factor A_j>=1, which makes it appear more attractive than the heavily-loaded macrocell. This paper bridges the gap between these approaches through several physical relaxations of the network-wide optimal association problem, whose solution is NP hard. We provide a low-complexity distributed algorithm that converges to a near-optimal solution with a theoretical performance guarantee, and we observe ...

  14. User Association in 5G Networks: A Survey and an Outlook

    OpenAIRE

    Liu, D.; Wang, L.; Chen, Y; Elkashlan, M; Wong, K-K; Schober, R; Hanzo, L.

    2015-01-01

    The fifth generation (5G) mobile networks are envisioned to support the deluge of data traffic with reduced energy consumption and improved quality of service (QoS) provision. To this end, key enabling technologies, such as heterogeneous networks (HetNets), massive multiple-input multiple-output (MIMO), and millimeter wave (mmWave) techniques, have been identified to bring 5G to fruition. Regardless of the technology adopted, a user association mechanism is needed to dete...

  15. 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…

  16. 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…

  17. 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.

  18. 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 /Wireless Broadband Technologies and Services for the Next Billion Users Fisseha Mekuria CSIR Meraka Institute Wireless Computing & Networking Research Pretoria 0001, South Africa. +27 12841 4606, fmekuria@csir.co.za Abstract- As wireless devices... generation radio network technologies and alternative energy usage to power the communications infrastructure are vital issues that should be addressed. Hence based on the above discussion, a sustainable and cost effective choice of mobile broadband...

  19. A mixing evolution model for bidirectional microblog user networks

    Science.gov (United States)

    Yuan, Wei-Guo; Liu, Yun

    2015-08-01

    Microblogs have been widely used as a new form of online social networking. Based on the user profile data collected from Sina Weibo, we find that the number of microblog user bidirectional friends approximately corresponds with the lognormal distribution. We then build two microblog user networks with real bidirectional relationships, both of which have not only small-world and scale-free but also some special properties, such as double power-law degree distribution, disassortative network, hierarchical and rich-club structure. Moreover, by detecting the community structures of the two real networks, we find both of their community scales follow an exponential distribution. Based on the empirical analysis, we present a novel evolution network model with mixed connection rules, including lognormal fitness preferential and random attachment, nearest neighbor interconnected in the same community, and global random associations in different communities. The simulation results show that our model is consistent with real network in many topology features.

  20. User Acceptance of Information Technology: Theories and Models.

    Science.gov (United States)

    Dillon, Andrew; Morris, Michael G.

    1996-01-01

    Reviews literature in user acceptance and resistance to information technology design and implementation. Examines innovation diffusion, technology design and implementation, human-computer interaction, and information systems. Concentrates on the determinants of user acceptance and resistance and emphasizes how researchers and developers can…

  1. Relay vs. User Cooperation in Time-Duplexed Multiaccess Networks

    CERN Document Server

    Sankar, Lalitha; Mandayam, Narayan B

    2008-01-01

    The performance of user-cooperation in a multi-access network is compared to that of using a wireless relay. Using the total transmit and processing power consumed at all nodes as a cost metric, the outage probabilities achieved by dynamic decode-and-forward (DDF) and amplify-and-forward (AF) are compared for the two networks. A geometry-inclusive high signal-to-noise ratio (SNR) outage analysis in conjunction with area-averaged numerical simulations shows that user and relay cooperation achieve a maximum diversity of K and 2 respectively for a K-user multiaccess network under both DDF and AF. However, when accounting for energy costs of processing and communication, relay cooperation can be more energy efficient than user cooperation, i.e., relay cooperation achieves coding (SNR) gains, particularly in the low SNR regime, that override the diversity advantage of user cooperation.

  2. 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...... look up the current location of other mobile users on a unified IP network by using a ¡§search by identifier¡¨ feature. Furthermore, the entire population of mobile terminals in a specific area is available for search requests.......This paper proposes a novel conceptual mechanism for detecting the location of a mobile user on next generation wireless networks. This mechanism can provide location information of a mobile user at different levels of accuracy, by applying the movement detection mechanism of Mobile IPv6 at both...

  3. Post-Polio Health International including International Ventilator Users Network

    Science.gov (United States)

    ... Place Explore the past, the present and help build a promising future for the world’s polio survivors. ... Polio Health International (PHI) Including International Ventilator Users Network 4207 Lindell Blvd., #110, Saint Louis, MO 63108- ...

  4. User support services and network application development: An overview

    Science.gov (United States)

    Gary, J. Patrick

    1991-01-01

    An overview is given of the user support services and network application development. The overview consists of the background, elements of NASA Science Internet (NSI) with GSFC responsibility, GSFC element objectives, and a summary of current status and plans. A conclusion of the overview is that refinement to the objectives and plans of the NSI elements under GSFC responsibility is ongoing and will continue to be influenced by user input/feedback through meetings with NSIUWG and user discipline programs, etc.

  5. fraud detection in mobile communications networks using user ...

    African Journals Online (AJOL)

    DEPT OF AGRICULTURAL ENGINEERING

    Keywords: Call data, fraud detection, neural networks, probabilistic models, user ... tion has been implemented by a number of ... call records delivered from cellular switches in ... tions of the brain, capable of predicting new ... these models make inferences about users' in- ... absolute certainty as same series of calls could.

  6. 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...... of scenarios and in developing innovative solutions on a conceptual level. The project discusses 1) concepts of users and 2) methods for collaborative involvement. The first discussion involves presentation of an extended user concept and a discussion of differences between lead users and need-advanced users....... 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...

  7. User Equilibrium Exchange Allocation Algorithm Based on Super Network

    Directory of Open Access Journals (Sweden)

    Peiyi Dong

    2013-12-01

    Full Text Available The theory of super network is an effective method to various traffic networks with means of multiple decision-making. It provides us with a favorable pricing decision tool for it combines a practical transport network with the space pricing decision. Spatial price equilibrium problem has always been the important research direction of the Transport Economics and regional transportation planning. As to how to combine the two, this paper presents the user equilibrium exchange allocation algorithm based on super network, which successfully keep the classical spatial price equilibrium problems (SPE into a super-network analysis framework. Through super-network analysis, we can add two virtual nodes in the network, which correspond to the virtual supply node and the super-super-demand virtual node, analysis the user equivalence with the SPE equilibrium and find the concrete steps of users exchange allocation algorithm based on super-network equilibrium. Finally, we carried out experiments to verify. The experiments show that: through the user equilibrium exchange SPE allocation algorithm based on super-network, we can get the steady-state equilibrium solution, which demonstrate that the algorithm is reasonable.

  8. 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.

  9. 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.

  10. Sexual risk and HIV prevention behaviours among African-American and Latino MSM social networking users.

    Science.gov (United States)

    Young, Sean D; Szekeres, Greg; Coates, Thomas

    2013-08-01

    This study explores the feasibility of recruiting minority men who have sex with men Facebook users for human immunodeficiency virus (HIV) prevention studies and notes demographic and sexual risk behaviours. Facebook-registered men who have sex with men (MSM; N = 118) were recruited using online and offline methods. Participants validated Facebook-user status through using a Facebook Connect (computer science) application. Participants were primarily Latino (60.2%) and African-American (28.0%), with 33.1% using social media to find sex partners. Black MSM social networking users reported engaging in a lower frequency (coefficient = -0.48, p < 0.05) of unprotected receptive anal intercourse compared to Latino MSM. Results suggest that minority social media users can be recruited for HIV studies and that sexual risk behavioural differences exist among minority social networking users. Findings highlight the importance of incorporating technologies into population-focused HIV interventions.

  11. Next generation network management technology

    Science.gov (United States)

    Baras, John S.; Atallah, George C.; Ball, Mike; Goli, Shravan; Karne, Ramesh K.; Kelley, Steve; Kumar, Harsha; Plaisant, Catherine; Roussopoulos, Nick; Schneiderman, Ben; Srinivasarao, Mulugu; Stathatos, Kosta; Teittinen, Marko; Whitefield, David

    1995-01-01

    Today's telecommunications networks are becoming increasingly large, complex, mission critical and heterogeneous in several dimensions. For example, the underlying physical transmission facilities of a given network may be ``mixed media'' (copper, fiber-optic, radio, and satellite); the subnetworks may be acquired from different vendors due to economic, performance, or general availability reasons; the information being transmitted over the network may be ``multimedia'' (video, data, voice, and images) and, finally, varying performance criteria may be imposed e.g., data transfer may require high throughput while the others, whose concern is voice communications, may require low call blocking probability. For these reasons, future telecommunications networks are expected to be highly complex in their services and operations. Due to this growing complexity and the disparity among management systems for individual sub-networks, efficient network management systems have become critical to the current and future success of telecommunications companies. This paper addresses a research and development effort which focuses on prototyping configuration management, since that is the central process of network management and all other network management functions must be built upon it. Our prototype incorporates ergonomically designed graphical user interfaces tailored to the network configuration management subsystem and to the proposed advanced object-oriented database structure. The resulting design concept follows open standards such as Open Systems Interconnection (OSI) and incorporates object oriented programming methodology to associate data with functions, permit customization, and provide an open architecture environment.

  12. A User Perspective on Social Networking Sites

    DEFF Research Database (Denmark)

    Sørensen, Lene Tolstrup; Porras, Jari; Hajikhani, Arash

    2014-01-01

    For years, social media have been a part of daily life. Within the last 5-10 years, the use of social media (and in particular social networking sites) has expanded to almost all sides of life: private people, businesses and public institutions. This paper presents an overview of different uses...... of social networks to give a picture of the variety in use. The paper describes differences in private persons’ use of social networking sites, different business purposes, and how social networking sites can challenge public administrations. Throughout the paper there are provided small cases...... and situations where the social networking sites have been used in a remarkable way. The paper is made in collaboration between partners in the World Wide Research Forum....

  13. A User Perspective on Social Networking Sites

    DEFF Research Database (Denmark)

    Sørensen, Lene Tolstrup; Porras, Jari; Hajikhani, Arash

    2014-01-01

    For years, social media have been a part of daily life. Within the last 5-10 years, the use of social media (and in particular social networking sites) has expanded to almost all sides of life: private people, businesses and public institutions. This paper presents an overview of different uses...... of social networks to give a picture of the variety in use. The paper describes differences in private persons’ use of social networking sites, different business purposes, and how social networking sites can challenge public administrations. Throughout the paper there are provided small cases...... and situations where the social networking sites have been used in a remarkable way. The paper is made in collaboration between partners in the World Wide Research Forum....

  14. Relay Selection and Performance Analysis in Multiple-User Networks

    CERN Document Server

    Atapattu, Saman; Jiang, Hai; Tellambura, Chintha

    2011-01-01

    This paper investigates the relay selection (RS) problem in networks with multiple users and multiple common amplify-and-forward (AF) relays. Considering the overall quality-of-service of the network, we first specify our definition of optimal RS for multiple-user relay networks. Then an optimal RS (ORS) algorithm is provided, which is a straightforward extension of an RS scheme in the literature that maximizes the minimum end-to-end receive signal-to-noise ratio (SNR) of all users. The complexity of the ORS is quadratic in both the number of users and the number of relays. Then a suboptimal RS (SRS) scheme is proposed, which has linear complexity in the number of relays and quadratic complexity in the number of users. Furthermore, diversity orders of both the ORS and the proposed SRS are theoretically derived and compared with those of a naive RS scheme and the single-user RS network. It is shown that the ORS achieves full diversity; while the diversity order of the SRS decreases with the the number of users...

  15. 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 ...

  16. 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.

  17. 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.

  18. User-level sentiment analysis incorporating social networks

    CERN Document Server

    Tan, Chenhao; Tang, Jie; Jiang, Long; Zhou, Ming; Li, Ping

    2011-01-01

    We show that information about social relationships can be used to improve user-level sentiment analysis. The main motivation behind our approach is that users that are somehow "connected" may be more likely to hold similar opinions; therefore, relationship information can complement what we can extract about a user's viewpoints from their utterances. Employing Twitter as a source for our experimental data, and working within a semi-supervised framework, we propose models that are induced either from the Twitter follower/followee network or from the network in Twitter formed by users referring to each other using "@" mentions. Our transductive learning results reveal that incorporating social-network information can indeed lead to statistically significant sentiment-classification improvements over the performance of an approach based on Support Vector Machines having access only to textual features.

  19. Research of user access control for networked manufacturing system

    Institute of Scientific and Technical Information of China (English)

    ZHENG Xiao-lin; LEI Yu; CHEN De-ren

    2006-01-01

    An integrated user access control method was proposed to address the issues of security and management in networked manufacturing systems (NMS).Based on the analysis of the security issues in networked manufacturing system,an integrated user access control method composed of role-based access control (RBAC),task-based access control (TBAC),relationship-driven access control (RDAC)and coalition-based access control (CBAC) was proposed,including the hierarchical user relationship model,the reference model and the process model.The elements and their relationships were defined,and the expressions of constraints authorization were given.The extensible access control markup language (XACML) was used to implement this method.This method was used in the networked manufacturing system in the Shaoxing spinning region of China.The results show that the integrated user access control method can reduce the costs of system security maintenance and management.

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

    Directory of Open Access Journals (Sweden)

    Chouyin Hsu

    2013-03-01

    Full Text Available 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 tools and impressive effects becomes the hot topic. Augmented Reality effect enables users to represent parts of the digital objects on top of the physical surroundings. The easy operation with webcam greatly improving the visual representation of web pages becomes the interest of our research. Therefore, we apply Augmented Reality technology for developing a city tour web site to collect the opinions of users. Therefore, the website stickiness is an important measurement. The major tasks of the work include the exploration of Augmented Reality technology and the evaluation of the outputs of Augmented Reality. The feedback opinions of users are valuable references for improving AR application in the work. As a result, the AR increasing the visual and interactive effects of web page encourages users to stay longer and more than 80% of users are willing to return for visiting the website soon. Moreover, several valuable conclusions about Augmented Reality technology in web user interface design are also provided for further practical references.

  1. Profiles of social networking sites users in the Netherlands

    OpenAIRE

    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. From the commercial perspective, the SNS are an interesting and promising field: online social networks are important sources of market intelligence and also offer interesting options for co-operat...

  2. 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

    2009-01-01

    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 is an approach that involves end users throughout the development process so that technologies support tasks, are easy to operate, and are of value to users. In this article, we provide an overview of user-centered design 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.

  3. Acoustic user interfaces for ambient-assisted living technologies.

    Science.gov (United States)

    Goetze, Stefan; Moritz, Niko; Appell, Jens-E; Meis, Markus; Bartsch, Christian; Bitzer, Jörg

    2010-01-01

    This contribution discusses technologies for acoustic user interaction in ambient-assisted living (AAL) scenarios. Acoustic user interfaces allow for a natural and convenient way to interact with technical systems e.g. via sound or speech presentation or via speech input by means of automatic speech recognition (ASR) as well as by detection and classification of acoustic events. Older persons targeted by AAL technologies especially need more easy-to-use methods to interact with inherently complex supporting technology. As an example we designed and evaluated an application for acoustic user interaction with a multi-media reminder and calendar system. For this purpose, mainly older participants were involved in user studies to continuously evaluate and support the development strictly following a user-centred design process. The results suggest a wide acceptance of acoustic user interfaces by older users either for controlling inherently complex AAL systems by using robust ASR technologies or as a natural and ambient way of presenting information to the user. However, further research is needed to increase the robustness of ASR systems when using hands-free equipment, i.e. to provide a real ambient way of interaction, and to introduce personalised speech and sound presentation schemes accounting for the individual hearing capabilities and sound preferences.

  4. Stimulant Use among African American and Latino MSM social networking users

    OpenAIRE

    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 state-of-the-art computer science methods, which narrowed the sample to 118 (primarily African American and Latino MSM) active Facebook users. ...

  5. User perceptions regarding sanitation technologies in South Africa

    CSIR Research Space (South Africa)

    Duncker, Louiza C

    2014-09-01

    Full Text Available -1 37th WEDC International Conference, Hanoi, Vietnam, 2014 Sustainable Water and Sanitation services for all in a fast changing world User perceptions regarding sanitation technologies in South Africa Ms L C. Duncker, South Africa Briefing...

  6. Camera location optimisation for traffic surveillance in urban road networks with multiple user classes

    Science.gov (United States)

    Lu, Xiao-Shan; Huang, Hai-Jun; Long, Jiancheng

    2013-12-01

    New sensor technologies (e.g. surveillance cameras, loop detectors) enable the synthesis of disaggregated vehicle information from multiple locations. This article studies the camera location problem for traffic surveillance in urban road networks with multiple user classes. All users are differentiated by their own acceptance degree of camera monitoring and make their route choices in a logit-based stochastic user equilibrium manner. A bi-level programming model is proposed to formulate the problem and solved by the sensitivity analysis based branch and bound method. Numerical examples are presented to illustrate the model application and show the effectiveness of the solution method.

  7. Textbook Websites: User Technology Acceptance Behaviour

    Science.gov (United States)

    Jonas, Gregory A.; Norman, Carolyn Strand

    2011-01-01

    Compared with course management software (e.g. Blackboard and WebCT), the content and technology offered by a textbook website (TBW) is relatively costless to universities and professors, and is a potentially valuable tool that can be leveraged to help students learn course material. The present study uses the extended Technology Acceptance Model…

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

    DEFF Research Database (Denmark)

    Schou, Saowanee; Olesen, Henning

    2005-01-01

    This paper proposes a novel conceptual mechanism for detecting the location of a mobile user on next generation wireless networks. This mechanism can provide location information of a mobile user at different levels of accuracy, by applying the movement detection mechanism of Mobile IPv6 at both...... 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...... macro- and micromobility level. In this scheme, an intradomain mobility management protocol (IDMP) is applied to manage the location of the mobile terminal. The mobile terminal needs two care-of addresses, a global care-of address (GCoA) and a local care-of address (LCoA). The current location...

  9. 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

    be used too early in the design process, given that users respond best to issues they know or can relate to. This paper presents a case study where a user-centred approach was used to determine when and how to involve users in the design of a TV-enabled mobile telephone. The aim of the study......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...

  10. 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.

  11. Community detection in networks: A user guide

    CERN Document Server

    Fortunato, Santo

    2016-01-01

    Community detection in networks is one of the most popular topics of modern network science. Communities, or clusters, are usually groups of vertices having higher probability of being connected to each other than to members of other groups, though other patterns are possible. Identifying communities is an ill-defined problem. There are no universal protocols on the fundamental ingredients, like the definition of community itself, nor on other crucial issues, like the validation of algorithms and the comparison of their performances. This has generated a number of confusions and misconceptions, which undermine the progress in the field. We offer a guided tour through the main aspects of the problem. We also point out strengths and weaknesses of popular methods, and give directions to their use.

  12. 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.

  13. 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.

  14. An Investigation of the Integrated Model of User Technology Acceptance: Internet User Samples in Four Countries

    Science.gov (United States)

    Fusilier, Marcelline; Durlabhji, Subhash; Cucchi, Alain

    2008-01-01

    National background of users may influence the process of technology acceptance. The present study explored this issue with the new, integrated technology use model proposed by Sun and Zhang (2006). Data were collected from samples of college students in India, Mauritius, Reunion Island, and United States. Questionnaire methodology and…

  15. Unsupervised user similarity mining in GSM sensor networks.

    Science.gov (United States)

    Shad, Shafqat Ali; Chen, Enhong

    2013-01-01

    Mobility data has attracted the researchers for the past few years because of its rich context and spatiotemporal nature, where this information can be used for potential applications like early warning system, route prediction, traffic management, advertisement, social networking, and community finding. All the mentioned applications are based on mobility profile building and user trend analysis, where mobility profile building is done through significant places extraction, user's actual movement prediction, and context awareness. However, significant places extraction and user's actual movement prediction for mobility profile building are a trivial task. In this paper, we present the user similarity mining-based methodology through user mobility profile building by using the semantic tagging information provided by user and basic GSM network architecture properties based on unsupervised clustering approach. As the mobility information is in low-level raw form, our proposed methodology successfully converts it to a high-level meaningful information by using the cell-Id location information rather than previously used location capturing methods like GPS, Infrared, and Wifi for profile mining and user similarity mining.

  16. Network-oriented or user-oriented?

    Science.gov (United States)

    Tirro, S.

    1986-12-01

    Optimized communications satellite services are identified, with emphasis on the benefits of large, multiuser spacecraft and the complementary nature of satellite system relative to fiber optics. Consideration is given to DBS, data transfer and collection, fixed-point and mobile communications networks. The costs of the space and ground segments are explored, along with the associated tariff structure and techniques for predicting the associated income. It is assumed that the satellite systems backup ground-based systems and also provide new digital services. A methodology is presented for optimizing satellite systems in terms of the ground-based capabilities and costs, the projected traffic, and the iterative space segment costs.

  17. Some Issues on Computer Networks: Architecture and Key Technologies

    Institute of Scientific and Technical Information of China (English)

    Guan-Qun Gu; Jun-Zhou Luo

    2006-01-01

    The evolution of computer networks has experienced several major steps, and research focus of each step has been kept changing and evolving, from ARPANET to OSI/RM, then HSN (high speed network) and HPN (high performance network). During the evolution, computer networks represented by Internet have made great progress and gained unprecedented success. However, with the appearance and intensification of tussle, along with the three difficult problems (service customizing, resource control and user management) of modern network, it is found that traditional Internet and its architecture no longer meet the requirements of next generation network. Therefore, it is the next generation network that current Internet must evolve to. With the mindset of achieving valuable guidance for research on next generation network, this paper firstly analyzes some dilemmas facing current Internet and its architecture, and then surveys some recent influential research work and progresses in computer networks and related areas, including new generation network architecture, network resource control technologies, network management and security, distributed computing and middleware,wireless/mobile network, new generation network services and applications, and foundational theories on network modeling.Finally, this paper concludes that within the research on next generation network, more attention should be paid to the high availability network and corresponding architecture, key theories and supporting technologies.

  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......, as virality is very important in social networks, we will describe the viral elements of Gedda-Headz. We will also introduce the Gedda-Headz spreader, a novel method to spread the word about the network, increasing the virality further....... 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. Online Kiosks: The Alternative to Mobile Technologies for Mobile Users.

    Science.gov (United States)

    Slack, Frances; Rowley, Jennifer

    2002-01-01

    Describes the development and use of online kiosks in contexts where users are away from fixed technologies. Uses a case study of a United Kingdom airport terminal to illustrate different types of kiosk applications; makes comparisons with mobile phone technologies; and considers their role in self-managed, self-service delivery of information and…

  20. 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.

  1. Earth Science Enterprise Solutions Network User Needs Analysis

    Science.gov (United States)

    Mita, D.; Easson, G.; Anderson, D. J.

    2006-12-01

    The University of Mississippi and Mississippi State University are partnering with National Aeronautics and Space Administration (NASA) to develop a Research Projects Knowledge Base (RPKB) and a Partner Network Knowledge Base (PNKB) that will allow the user community to more easily locate the results of NASA funded research and be able to contact potential partners for future research. The RPKB and PNKB will also help NASA and the user community generate new topics for research projects that benefit society. The assessment of the needs of the user community for the RPKB and the PNKB was conducted through a combination of phone interviews with representatives of the user community, evaluations of existing data and tools currently employed by scientists, collaborations between NASA and the MRC, and the results of a November, 2006 workshop. This information was combined with an email survey, resulting in a report that describes how the users of the RPKB and the PNKB want to access the information in the knowledge bases, input new information into the RPKB and PNKB, and generate reports and diagrams, such as formulation reports. The compilation of the user's needs presented here is being used to design access and input tools for the user community. When fully developed the RPKB and the PNKB will use the NASA enterprise architecture modeling and viewing capability to provide NASA and the user community a more efficient way to identify potential research projects and partners.

  2. 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...... 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....

  3. 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

  4. 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.

  5. User-driven innovation in Supply and Value Networks

    DEFF Research Database (Denmark)

    Lassen, Astrid Heidemann; Jacobsen, Alexia; Wandahl, Søren;

    2011-01-01

    In order to address the lack of knowledge about readiness for implementing user-driven innovation at a network level, this paper develops a conceptual framework for assessment, and tests this in the context of the building material industry in Denmark. The results illustrate significant differenc...

  6. 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...

  7. 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...

  8. BECUN. The Educational Computer User's Network at Battelle.

    Science.gov (United States)

    Battelle Memorial Inst., Columbus, OH.

    The Educational Computer User's Network at Battelle Columbus Laboratories is a cooperative computer center effort between a group of Ohio colleges, secondary schools, and a large research-oriented organization. This description of the program includes the historical background, program concept, data processing development, hardware and software,…

  9. Learning User Intention in Networked Mobile Robot Control

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Teleoperated networked robot often has unpredictable behaviors due to uncertain time delay from data transmission over Internet. The robot cannot accomplish the desired actions of the remote operator in time, which severely impairs reliability and efficiency of the robot system. This paper investigated a novel approach, learning user intention, to compensate the uncertain time delay with the autonomy of a mobile robot. The user intention to control and operate the robot was modeled and incrementally inferred based on Bayesian techniques so that the desired actions could be recognized and completed by the robot autonomously. Thus the networked robot is able to fulfill the task assigned without frequent interaction with the user, which decreases data transmission and improves the efficiency of the whole system. Experimental results show the validity and feasibility of the proposed method.

  10. User involvement in assisted reproductive technologies: England and Portugal.

    Science.gov (United States)

    Samorinha, Catarina; Lichon, Mateusz; Silva, Susana; Dent, Mike

    2015-01-01

    The purpose of this paper is to compare user involvement in the case of assisted reproductive technologies in England and Portugal through the concepts of voice, choice and co-production, assessing the implications for user empowerment. This qualitative study draws primarily on policy review and uses exploratory semi-structured interviews with key informants as a way of illustrating points. Data on the following themes was compared: voice (users' representativeness on licensing bodies and channels of communication between users and doctors); choice (funding and accessibility criteria; choice of fertility centres, doctors and level of care); and co-production (criteria through which users actively engage with health professionals in planning the treatment). Inter- and intra-healthcare systems variations between the two countries on choice and co-production were identified. Differences between funding and accessibility, regions, public and private sectors and attitudes towards doctor-patient relationship (paternalistic/partnership) were the key issues. Although consumer choice and indicators of co-production are evident in treatment pathways in both countries, user empowerment is not. This is limited by inequalities in accessibility criteria, dependence on doctors' individual perspectives and lack of genuine and formal hearing of citizens' voice. Enhancing users' involvement claims for individual and organizational cultures reflecting user-centred values. Effective ways to incorporate users' knowledge in shared decision making and co-design are needed to empower patients and to improve the delivery of care.

  11. Mapping Technology Space by Normalizing Technology Relatedness Networks

    CERN Document Server

    Alstott, Jeff; Yan, Bowen; Luo, Jianxi

    2015-01-01

    Technology is a complex system, with technologies relating to each other in a space that can be mapped as a network. The technology relatedness network's structure can reveal properties of technologies and of human behavior, if it can be mapped accurately. Technology networks have been made from patent data, using several measures of relatedness. These measures, however, are influenced by factors of the patenting system that do not reflect technologies or their relatedness. We created technology networks that precisely controlled for these impinging factors and normalized them out, using data from 3.9 million patents. The normalized technology relatedness networks were sparse, with only ~20% of technology domain pairs more related than would be expected by chance. Different measures of technology relatedness became more correlated with each other after normalization, approaching a single dimension of technology relatedness. The normalized network corresponded with human behavior: we analyzed the patenting his...

  12. Ultrafast technologies for photonic networks

    Science.gov (United States)

    Prucnal, Paul R.; Baby, Varghese; Xu, Lei; Glesk, Ivan

    2004-10-01

    Considerable progress has been in the last decade in the fields of photonic networks and ultra-fast optics. The past few years has seen the widespread use of wavelength division multiplexing (WDM) to provide enormous point-to-point capacity in the backbone and metro area networks. Remarkable progress in electronics, in terms of both costs and performance speeds, has to some extent alleviated the 'electronic bottleneck'. Developments in fiber-optics such as novel fiber types and Raman amplification have opened up additional wavelength regions of operation resulting in great expansion of usable fiber bandwidth. There exist unique opportunities for ultrafast technologies - a subject of much interest in the last decade and reaching a point of maturity - to complement these advances and spark the next generation networks. In our talk, we will mention two networking environments very different from WDM - (1) optical time division multiplexing (OTDM) and (2) optical code division multiple access (OCDMA). We will look at the potential of both these scenarios for different applications, focusing in particular on the latter as an approach that provides maximum flexibility to utilize the immense bandwidth of the optical fiber. We will also describe various ultra-fast technologies that have been developed e.g. .high repetition rate pulsed lasers, ultra-fast optical switches, time delay elements etc. which have a direct relevance to both these types of networks.

  13. 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.

  14. WHAT ARE USER PERSPECTIVES OF EXOSKELETON TECHNOLOGY? A LITERATURE REVIEW.

    Science.gov (United States)

    Hill, Deborah; Holloway, Catherine Sarah; Morgado Ramirez, Dafne Zuleima; Smitham, Peter; Pappas, Yannis

    2017-01-01

    Exoskeletons are electromechanical devices that are worn by a human operator to increase their physical performance. Several exoskeletons have been developed to restore functional movements, such as walking, for those with paralysis due to neurological impairment. However, existing exoskeletons have limitations with respect to affordability, size, weight, speed, and efficiency, which may reduce their functional application. Therefore, the aim of this scoping review is to collect and narratively synthesize the perspectives of users of exoskeleton technology. A systematic literature search was conducted across several healthcare related online databases. A total of 4,619 articles were identified, of which 51 were selected for full review. Only three studies were identified that met the inclusion criteria. Of these, one showed an incongruence between users' expectations and experiences of device use; another reported perspectives on potential rather than actual device use, ranking design features in order of perceived importance; and the other reported ratings of ease of device use in training. The heterogeneity of studies included within this review, leave the authors unable to suggest consensus as to user perspectives of exoskeleton technology. However, it is apparent that users are able to suggest priorities for exoskeleton design and that users' perspectives of exoskeleton technology might change in response to experience of use. The authors, therefore, suggest that exoskeleton design should be an iterative process, whereby user perspectives are sought, incorporated and refined by tangible experience, to ensure that devices developed are acceptable to and usable by the populations they seek to re-enable.

  15. 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.

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

    DEFF Research Database (Denmark)

    Hillmann, Robert; Trier, Matthias

    2012-01-01

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

  17. 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...

  18. 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

  19. Network capacity with probit-based stochastic user equilibrium problem

    Science.gov (United States)

    Lu, Lili; Wang, Jian; Zheng, Pengjun; Wang, Wei

    2017-01-01

    Among different stochastic user equilibrium (SUE) traffic assignment models, the Logit-based stochastic user equilibrium (SUE) is extensively investigated by researchers. It is constantly formulated as the low-level problem to describe the drivers’ route choice behavior in bi-level problems such as network design, toll optimization et al. The Probit-based SUE model receives far less attention compared with Logit-based model albeit the assignment result is more consistent with drivers’ behavior. It is well-known that due to the identical and irrelevant alternative (IIA) assumption, the Logit-based SUE model is incapable to deal with route overlapping problem and cannot account for perception variance with respect to trips. This paper aims to explore the network capacity with Probit-based traffic assignment model and investigate the differences of it is with Logit-based SUE traffic assignment models. The network capacity is formulated as a bi-level programming where the up-level program is to maximize the network capacity through optimizing input parameters (O-D multiplies and signal splits) while the low-level program is the Logit-based or Probit-based SUE problem formulated to model the drivers’ route choice. A heuristic algorithm based on sensitivity analysis of SUE problem is detailed presented to solve the proposed bi-level program. Three numerical example networks are used to discuss the differences of network capacity between Logit-based SUE constraint and Probit-based SUE constraint. This study finds that while the network capacity show different results between Probit-based SUE and Logit-based SUE constraints, the variation pattern of network capacity with respect to increased level of travelers’ information for general network under the two type of SUE problems is the same, and with certain level of travelers’ information, both of them can achieve the same maximum network capacity. PMID:28178284

  20. Designing for older adult users of handheld technology.

    Science.gov (United States)

    Becker, Shirley Ann; Webbe, Frank M

    2006-01-01

    There are few interface design guidelines for handheld devices used by adults sixty years and older. Yet, this growing user group would benefit from the portability offered by such technology in promoting health management and social interaction. In this paper, we describe a usability framework for conducting studies on the use of a PocketPC by older adult caregivers. The usability framework provides a basis for conducting studies taking into account the user profile of an older adult, environment factors, usability quality factors, and technology objectives.

  1. Unsupervised User Similarity Mining in GSM Sensor Networks

    Directory of Open Access Journals (Sweden)

    Shafqat Ali Shad

    2013-01-01

    Full Text Available Mobility data has attracted the researchers for the past few years because of its rich context and spatiotemporal nature, where this information can be used for potential applications like early warning system, route prediction, traffic management, advertisement, social networking, and community finding. All the mentioned applications are based on mobility profile building and user trend analysis, where mobility profile building is done through significant places extraction, user’s actual movement prediction, and context awareness. However, significant places extraction and user’s actual movement prediction for mobility profile building are a trivial task. In this paper, we present the user similarity mining-based methodology through user mobility profile building by using the semantic tagging information provided by user and basic GSM network architecture properties based on unsupervised clustering approach. As the mobility information is in low-level raw form, our proposed methodology successfully converts it to a high-level meaningful information by using the cell-Id location information rather than previously used location capturing methods like GPS, Infrared, and Wifi for profile mining and user similarity mining.

  2. 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.

  3. Mobile Network DoS Attack and Detection Technology

    Directory of Open Access Journals (Sweden)

    K. Krishnamoorthy

    2013-09-01

    Full Text Available Currently, there has been a 3G mobile networks data traffic explosion due to the large increase in the number of smartphone users. Unlike a traditional wired infrastructure, 3G mobile networks have limited wireless resources and signaling procedures for complex wireless resource management and mobile network security for various abnormal and malicious traffic technologies was not ready. So Malicious or potentially malicious traffic originating from mobile malware infected smart devices can cause serious problems to the 3G mobile networks, such as DoS and scanning attack in wired networks. This paper describes the DoS security threat in the 3G mobile network and proposes a detection technology.

  4. Technology Benefit Estimator (T/BEST): User's Manual

    Science.gov (United States)

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

    1994-01-01

    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

  5. 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

  6. Resilient Disaster Network Based on Software Defined Cognitive Wireless Network Technology

    Directory of Open Access Journals (Sweden)

    Goshi Sato

    2015-01-01

    Full Text Available In order to temporally recover the information network infrastructure in disaster areas from the Great East Japan Earthquake in 2011, various wireless network technologies such as satellite IP network, 3G, and Wi-Fi were effectively used. However, since those wireless networks are individually introduced and installed but not totally integrated, some of networks were congested due to the sudden network traffic generation and unbalanced traffic distribution, and eventually the total network could not effectively function. In this paper, we propose a disaster resilient network which integrates various wireless networks into a cognitive wireless network that users can use as an access network to the Internet at the serious disaster occurrence. We designed and developed the disaster resilient network based on software defined network (SDN technology to automatically select the best network link and route among the possible access networks to the Internet by periodically monitoring their network states and evaluate those using extended AHP method. In order to verify the usefulness of our proposed system, a prototype system is constructed and its performance is evaluated.

  7. Users' satisfaction with Porto Alegre's Primary Care Network

    Directory of Open Access Journals (Sweden)

    Aline do Amaral Zils

    2010-11-01

    Full Text Available Users' satisfaction is an important end-point to evaluate health services. This study has to do with an assessment of the level of user's satisfaction with relation to the last visit held in the primary health care network of Porto Alegre — RS, whose objective is to compare satisfaction of the users that assess the quality of the care process received as being of high APS score with that of the users who evaluate it as low APS score. A cross-sectional study based on the population, using the Primary Care Assessment Tool - PCATool, which enables the classification of the health services at the level of guidance to APS by means of the general score of primary care, defining it as high or low, in accordance with the users' experience. The satisfaction of the user was measured by a questionnaire consisting of twelve questions relative to the last visit, being measured by a 5-item Likert scale: "very good", "good", "regular", "bad" and "very bad". For the analysis, the results were grouped into two classifications, i.e. "satisfied", when referred as "veg good" or "good", and "dissatisfied" when referred to any of the other items. A significant difference was noticed in the 12 variables reflecting satisfaction in several aspects of the visit, showing higher satisfaction in users that classified the service as being of high score. The .general evaluation of the service presented 95.6% and 73.5% of "satisfied" in the services with high and low APS score, respectively (p<0.001. Users of services with high level of guidance to primary care obtain higher satisfaction in their visits. This higher satisfaction can benefit the decision-making process of the patient in face of the medical recommendations made.

  8. Investigation of user behavior on social networking sites.

    Science.gov (United States)

    Waheed, Hajra; Anjum, Maria; Rehman, Mariam; Khawaja, Amina

    2017-01-01

    Social networking sites (SNS) are used for social and professional interaction with people. SNS popularity has encouraged researchers to analyze the relationship of activities performed on SNS with user behavior. In doing so, the term "user behavior" is rather used ambiguously with different interpretations, which makes it difficult to identify studies on user behavior in relation to SNS. This phenomenon has encouraged this thorough research on the characteristics of user behavior being discussed in the literature. Therefore, in this study, we aim to identify, analyze, and classify the characteristics associated with user behavior to answer the research questions designed to conduct this research. A mapping study (also called scoping study), which is a type of systematic literature review, is employed to identify potential studies from digital databases through a developed protocol. Thematic analysis is carried out for the classification of user behavior. We identified 116 primary studies for full analysis. This study found seven characteristics associated with behavior that have direct influence on SNS use and nine factors that have an indirect effect. All studies were conducted largely under seven areas that set the context of these studies. Findings show that the research on SNS is still in its early stage. The range of topics covered in the analyzed studies is quite expansive, although the depth in terms of number of studies under each topic is quite limited. This study reports that activities performed on SNS are either associated with user behavior or reflect personality characteristics. The findings of this study could be used by practitioners to evaluate their SNS platforms and develop more user-centered applications. These studies can also help organizations to understand better the needs of their employees.

  9. Investigation of user behavior on social networking sites

    Science.gov (United States)

    2017-01-01

    Social networking sites (SNS) are used for social and professional interaction with people. SNS popularity has encouraged researchers to analyze the relationship of activities performed on SNS with user behavior. In doing so, the term “user behavior” is rather used ambiguously with different interpretations, which makes it difficult to identify studies on user behavior in relation to SNS. This phenomenon has encouraged this thorough research on the characteristics of user behavior being discussed in the literature. Therefore, in this study, we aim to identify, analyze, and classify the characteristics associated with user behavior to answer the research questions designed to conduct this research. A mapping study (also called scoping study), which is a type of systematic literature review, is employed to identify potential studies from digital databases through a developed protocol. Thematic analysis is carried out for the classification of user behavior. We identified 116 primary studies for full analysis. This study found seven characteristics associated with behavior that have direct influence on SNS use and nine factors that have an indirect effect. All studies were conducted largely under seven areas that set the context of these studies. Findings show that the research on SNS is still in its early stage. The range of topics covered in the analyzed studies is quite expansive, although the depth in terms of number of studies under each topic is quite limited. This study reports that activities performed on SNS are either associated with user behavior or reflect personality characteristics. The findings of this study could be used by practitioners to evaluate their SNS platforms and develop more user-centered applications. These studies can also help organizations to understand better the needs of their employees. PMID:28151963

  10. Teknologvurdering, Broer og Brugere (Technology Assessment: Bridges and Users)

    DEFF Research Database (Denmark)

    Munch, Birgitte

    A critique of the scientific approaches grounding Danish technology assessments for beingnon-reflexive upon the consequences of its biased treatment of who and how some countsas ‘users'. Implications and new approaches are outlined in a story of engineering designers conceptualization of ships...

  11. Assistive Technology User Group Perspectives of Early Childhood Professionals

    Science.gov (United States)

    Parette, Howard P.; Stoner, Julia B.; Watts, Emily H.

    2009-01-01

    With the increasing usage of assistive technology (AT) usage in early childhood education settings serving children who are at-risk or who have developmental disabilities, there is a corresponding need for effective professional development experiences such as user groups to develop skills in using AT. Using a collective case study approach, 10…

  12. Learning Probabilistic Hierarchical Task Networks to Capture User Preferences

    CERN Document Server

    Li, Nan; Kambhampati, Subbarao; Yoon, Sungwook

    2010-01-01

    We propose automatically learning probabilistic Hierarchical Task Networks (pHTNs) in order to capture a user's preferences on plans, by observing only the user's behavior. HTNs are a common choice of representation for a variety of purposes in planning, including work on learning in planning. Our contributions are (a) learning structure and (b) representing preferences. In contrast, prior work employing HTNs considers learning method preconditions (instead of structure) and representing domain physics or search control knowledge (rather than preferences). Initially we will assume that the observed distribution of plans is an accurate representation of user preference, and then generalize to the situation where feasibility constraints frequently prevent the execution of preferred plans. In order to learn a distribution on plans we adapt an Expectation-Maximization (EM) technique from the discipline of (probabilistic) grammar induction, taking the perspective of task reductions as productions in a context-free...

  13. Mass storage technology in networks

    Science.gov (United States)

    Ishii, Katsunori; Takeda, Toru; Itao, Kiyoshi; Kaneko, Reizo

    1990-08-01

    Trends and features of mass storage subsystems in network are surveyed and their key technologies spotlighted. Storage subsystems are becoming increasingly important in new network systems in which communications and data processing are systematically combined. These systems require a new class of high-performance mass-information storage in order to effectively utilize their processing power. The requirements of high transfer rates, high transactional rates and large storage capacities, coupled with high functionality, fault tolerance and flexibility in configuration, are major challenges in storage subsystems. Recent progress in optical disk technology has resulted in improved performance of on-line external memories to optical disk drives, which are competing with mid-range magnetic disks. Optical disks are more effective than magnetic disks in using low-traffic random-access file storing multimedia data that requires large capacity, such as in archive use and in information distribution use by ROM disks. Finally, it demonstrates image coded document file servers for local area network use that employ 130mm rewritable magneto-optical disk subsystems.

  14. Effective Voice Calls Admission for Authorized User in Inter VOIP Network

    Directory of Open Access Journals (Sweden)

    Subashri T

    2010-10-01

    Full Text Available IP based voice transmission technology is a flexible, simpler and a cost effective implementation of voicetransmission. It provides a real convergence of various networks. This voice transmission technology doesnot support a quality that is equivalent to digitized voice, which is available in the existing PSTN networks.In addition to this, data network vulnerabilities affect the VOIP service causing a drop in the utilization ofvoice communication. In this paper, the quality of service for voice calls is ensured with the integration ofCAC mechanism with the bandwidth link utilization which makes an estimation of the demandedbandwidth. In terms of security, prevention of ARP cache poisoning attack is achieved by use of the signedMAC address response in local area networks. It makes the network confident that the admitted user is anauthorized user and also it verifies that only the authorized users’ information is exchanged over the localarea network. Also an approach that makes it difficult for the hacker’s to hack the data exchanged over thequality channel has been proposed.

  15. 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

  16. 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...

  17. Network technology for depot modernization

    Energy Technology Data Exchange (ETDEWEB)

    Hostick, C.J.

    1990-12-01

    This report was prepared by the Pacific Northwest Laboratory to summarize existing and emerging information system technology and standards applicable to Depot System Command (DESCOM) modernization efforts. The intent of this summarization is to provide the Revitalization of Army Depots for the Year 2000 (READY 2000) team a clear understanding of the enabling information system technologies required to support effective modernization activities. Much of the information contained in this report was acquired during the last year in support of the US Army Armament, Munitions, and Chemical Command (AMCCOM) Facility Integrated Manufacturing Management System (FIMMS) project at PNL, which is targeting the modernization of plant-wide information systems at Army Ammunition Plants. The objective of information system modernization is to improve the effectiveness of an organization in performing its mission. Information system modernization strives to meet this objective by creating an environment where data is electronically captured near the source and readily available to all areas of the organization. Advanced networks, together with related information system technology, are the enabling mechanisms that make modern information system infrastructures possible. The intent of this paper is to present an overview of advanced information system network technology to support depot modernization planners in making technology management decisions. Existing and emerging Open System Interconnection (OSI) and Government Open System Interconnection Profile (GOSIP) standards are explained, as well as a brief assessment of existing products compliant with these standards. Finally, recommendations for achieving plant-wide integration using existing products are presented, and migration strategies for full OSI compliance are introduced. 5 refs., 16 figs. (JF)

  18. 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.

  19. 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.

  20. On the Political Value of Network Technology

    Institute of Scientific and Technical Information of China (English)

    Gong Xiaoping

    2011-01-01

    Since the 1990s,with the emergence of the Internet,rapid development of network technology,based on computer technology,communication technology and information technology,has affected all aspects of social life.As the network technology has the characteristics of openness,interactivity,anonymity,transparency,globalization and the decentralization,it is becoming more and more popular and adds a number of new technologies of variables and restrictive factors into traditional sense of political participation and political control mode.The links between Internet and politics grow increasingly and the political value of network technology becomes more prominent.

  1. 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

  2. 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

  3. Assistive Technology: Bridging End-users and Technology%Assistive Technology:Bridging End-users and Technology

    Institute of Scientific and Technical Information of China (English)

    Renzo Andrich; Serenella Besio

    2011-01-01

    One of the basic aspects that determines the success or failure in the use of assistive technologies on the part of people with disabilities is constituted by the ability that provide a disabled person with the technology that corresponds effectively to his needs and to his capabilities,thus to interpret correctly the problems and to find the right ways of transferring this technological "knowledge".If the aids answer the effective needs and capabilities of the person he can achieve significant improvement to reach the goals of his individual rehabilitative project.The article highlights the key factors of success.

  4. User-friendly Establishment of Trust in Distributed Home Automation Networks

    DEFF Research Database (Denmark)

    Solberg Hjorth, Theis; 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...

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

    DEFF Research Database (Denmark)

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

    2012-01-01

    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...

  6. 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

  7. Wi-Fi Wireless Networks and Technology

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Most agree that wireless networking represent the future of computer and Internet connectivity worldwide.Wi-Fi continues to be the pre-eminent technology for building general-purpose wireless networks. 1 What is Wireless Networking? Wireless networks utilize radio waves and/or microwaves to maintain communication channels between computers.Wireless net- working is a more modern alternative to wired networking that relies on copper and/or fiber optic cabling between network devices.

  8. 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.

  9. 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. PMID:25489942

  10. 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.

  11. Key User Extraction Based on Telecommunication Data (aka. Key Users in Social Network. How to find them?)

    CERN Document Server

    Bródka, Piotr

    2013-01-01

    The number of systems that collect vast amount of data about users rapidly grow during last few years. Many of these systems contain data not only about people characteristics but also about their relationships with other system users. From this kind of data it is possible to extract a social network that reflects the connections between system's users. Moreover, the analysis of such social network enables to investigate different characteristics of its members and their linkages. One of the types of examining such network is key users extraction. Key users are these who have the biggest impact on other network members as well as have big influence on network evolution. The obtained about these users knowledge enables to investigate and predict changes within the network. So this knowledge is very important for the people or companies who make a profit from the network like telecommunication company. The second important thing is the ability to extract these users as quick as possible, i.e. developed the algo...

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

    Science.gov (United States)

    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. PMID:28278242

  13. 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 ...

  14. 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.

  15. Understanding IT-enabled social action networks: construction, sustainability, and user participation.

    Science.gov (United States)

    Banks, M Shane

    2012-01-01

    Innovative, humanitarian individuals and organizations are seeking to leverage the power of information technologies by constructing IT-enabled social action networks (ITSANs), networks of actors, connected via an IT platform, working together to improve social conditions and the lives of others. ITSANs are primarily web-based platforms that allow users to collaborate, share information, and pool resources to enhance efforts to address a common social mission. The goal of this research is to investigate how ITSANs are used to positively affect social needs by examining how these platforms are constructed and sustained. Also of interest are factors influencing user participation. To develop an in-depth understanding of ITSANs, this research proposes a qualitative multi-case study approach that seeks to understand ITSANs through the lived experiences of key actors.

  16. 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....

  17. Interference-Limited Device-to-Device Multi-User Cooperation Scheme for Optimization of Edge Networking

    Institute of Scientific and Technical Information of China (English)

    Hong-Cheng Huang; Jie Zhang; Zu-Fan Zhang; Zhong-Yang Xiong

    2016-01-01

    Device-to-device (D2D) communication is an emerging technology for improving cellular networks, which plays an important role in realizing Internet of Things (IoT). The spectrum efficiency, energy efficiency and throughput of network can be enhanced by the cooperation among multiple D2D users in a self-organized method. In order to limit the interference of D2D users and load off the energy consumption of D2D users without decreasing communication quality, an interference-limited multi-user cooperation scheme is proposed for multiple D2D users to solve the energy problem and the interference problem in this paper. Multiple D2D users use non-orthogonal spectrums to form clusters by self-organized method. Multiple D2D users are divided into different cooperative units. There is no interference among different cooperative units so as to limit the interference of each D2D user in cooperative units. When the link capacity cannot meet the requirements of the user rate, it will produce an interrupt event. In order to evaluate the communication quality, the outrage probability of D2D link is derived by considering link delay threshold, data rate and interference. Besides the energy availability and signal-to-noise ratio (SNR) of each D2D user, the distance between D2D users is considered when selecting the relaying D2D users so as to enhance the signal-to-interference-plus-noise ratio (SINR) of D2D receiving users. Combining the derived outrage probability, the relationships among the average link delay threshold, the efficiency of energy and the efficiency of capacity are studied. The simulation results show that the interference-limited multiple D2D users cooperation scheme can not only help to offload energy consumption and limit the interference of D2D users, but also enhance the efficiency of energy and the efficiency of capacity.

  18. 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.

  19. Advanced radio over fiber network technologies.

    Science.gov (United States)

    Novak, Dalma; Waterhouse, Rod

    2013-09-23

    The evolution of wireless communication networks supporting emerging broadband services and applications offers new opportunities for realizing integrated optical and wireless network infrastructures. We report on some of our recent activities investigating advanced technologies for next generation converged optical wireless networks. Developments in Active Antenna Systems, mobile fronthaul architectures, and 60 GHz fiber distributed wireless networks are described. We also discuss the potential for analog radio over fiber distribution links as a viable solution for meeting the capacity requirements of new network architectures.

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

    OpenAIRE

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

    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 ...

  1. 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.

  2. 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.

  3. 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...

  4. 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

  5. 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

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

    Science.gov (United States)

    Åkerberg, Anna; Söderlund, Anne; Lindén, Maria

    2017-01-01

    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 than differences in opinions about the PA self-monitoring technologies.

  7. 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

  8. 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....

  9. 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.

  10. Privacy and technology challenges for ubiquitous social networking

    DEFF Research Database (Denmark)

    Sapuppo, Antonio; Seet, Boon-Chong

    2015-01-01

    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...... 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...

  11. 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.)

  12. 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.

  13. Future networks and technologies supporting innovative communications

    DEFF Research Database (Denmark)

    Prasad, Ramjee

    2012-01-01

    Within a fully interconnected world, the distinct relationship between end users, consumers and providers rapidly changes towards a scenario of collaboration and competition of multiple parties within one system. ‘Convergence’, ‘ubiquitous’ and ‘smart’ are key words describing future networks...

  14. Application of ATM technology to the Systems Management Department Computer Laboratory Network

    OpenAIRE

    Williams, Robert

    1996-01-01

    Approved for public release; distribution is unlimited. Since the appearance of Local Area Networks (LANs), their use and bandwidth consumption have increased considerably. Users are now seeking new technologies to satisfy their bandwidth demand. Many consider ATM as the solution to their needs. Though ATM is fairly new networking technology, it has made several strides, and is now considered a viable technology that is applicable LAN environment. However, migrating from today's shared-med...

  15. 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 wit

  16. 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

  17. Discovering Mobile Social Networks by Semantic Technologies

    Science.gov (United States)

    Jung, Jason J.; Choi, Kwang Sun; Park, Sung Hyuk

    It has been important for telecommunication companies to discover social networks from mobile subscribers. They have attempted to provide a number of recommendation services, but they realized that the services were not successful. In this chapter, we present semantic technologies for discovering social networks. The process is mainly composed of two steps; (1) profile identification and (2) context understanding. Through developing a Next generation Contents dElivery (NICE) platform, we were able to generate various services based on the discovered social networks.

  18. 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.

  19. The role of networks in the dissemination of clean technologies

    Energy Technology Data Exchange (ETDEWEB)

    Janssen, M. [KEMA, Arnhem (Netherlands)

    2003-07-01

    Information from scientific research projects is generally disseminated to potential users (Small Medium Enterprises (SME) and industries) through scientific papers and conferences. The author presents a more effective way to disseminate this valuable information to SMEs. The proposed approach was introduced by Thematic Networks within the Fifth Frame Programme of the European Commission (EC). The Network was created to provide a smooth transmission of knowledge from those who generate the information to those who use it. The author discussed the role of Thematic Network in relation to the Consortium entitled Production of Novel Products from Glassy Combustion Residues (PROGRES). The Network resulted in a pan-European discussion platform to study issues associated with advanced uses for combustion residues as secondary raw materials. Emphasis was placed on new advanced technologies for fly ash based products under practical conditions. This topic will be discussed in a book being completed by an International PROGRES Consortium. It will describe new technologies for coal fly ash based products. When launching new products, consideration will be given to all stakeholders, from producers of residues to potential users. 2 figs.

  20. 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...

  1. User requirements and future expectations for geosensor networks – an assessment

    NARCIS (Netherlands)

    Kooistra, L.; Thessler, S.; Bregt, A.K.

    2009-01-01

    Considerable progress has been made on the technical development of sensor networks. However increasing attention is now also required for the broad diversity of end-user requirements for the deployment of sensor networks. An expert survey on the user requirements and future expectations for sensor

  2. REGIONAL WEBGIS USER ACCESS PATTERNS BASED ON A WEIGHTED BIPARTITE NETWORK

    Directory of Open Access Journals (Sweden)

    R. Li

    2015-07-01

    Full Text Available With the rapid development of geographic information services, Web Geographic Information Systems (WebGIS have become an indispensable part of everyday life; correspondingly, map search engines have become extremely popular with users and WebGIS sites receive a massive volume of requests for access. These WebGIS users and the content accessed have regional characteristics; to understand regional patterns, we mined regional WebGIS user access patterns based on a weighted bipartite network. We first established a weighted bipartite network model for regional user access to a WebGIS. Then, based on the massive user WebGIS access logs, we clustered geographic information accessed and thereby identified hot access areas. Finally we quantitatively analyzed the access interests of regional users and the visitation volume characteristics of regional user access to these hot access areas in terms of user access permeability, user usage rate, and user access viscosity. Our research results show that regional user access to WebGIS is spatially aggregated, and the hot access areas that regional users accessed are associated with specific periods of time. Most regional user contact with hot accessed areas is variable and intermittent but for some users, their access to certain areas is continuous as it is associated with ongoing or recurrent objectives. The weighted bipartite network model for regional user WebGIS access provides a valid analysis method for studying user behaviour in WebGIS and the proposed access pattern exhibits access interest of regional user is spatiotemporal aggregated and presents a heavy-tailed distribution. Understanding user access patterns is good for WebGIS providers and supports better operational decision-making, and helpful for developers when optimizing WebGIS system architecture and deployment, so as to improve the user experience and to expand the popularity of WebGIS.

  3. Regional Webgis User Access Patterns Based on a Weighted Bipartite Network

    Science.gov (United States)

    Li, R.; Shen, Y.; Huang, W.; Wu, H.

    2015-07-01

    With the rapid development of geographic information services, Web Geographic Information Systems (WebGIS) have become an indispensable part of everyday life; correspondingly, map search engines have become extremely popular with users and WebGIS sites receive a massive volume of requests for access. These WebGIS users and the content accessed have regional characteristics; to understand regional patterns, we mined regional WebGIS user access patterns based on a weighted bipartite network. We first established a weighted bipartite network model for regional user access to a WebGIS. Then, based on the massive user WebGIS access logs, we clustered geographic information accessed and thereby identified hot access areas. Finally we quantitatively analyzed the access interests of regional users and the visitation volume characteristics of regional user access to these hot access areas in terms of user access permeability, user usage rate, and user access viscosity. Our research results show that regional user access to WebGIS is spatially aggregated, and the hot access areas that regional users accessed are associated with specific periods of time. Most regional user contact with hot accessed areas is variable and intermittent but for some users, their access to certain areas is continuous as it is associated with ongoing or recurrent objectives. The weighted bipartite network model for regional user WebGIS access provides a valid analysis method for studying user behaviour in WebGIS and the proposed access pattern exhibits access interest of regional user is spatiotemporal aggregated and presents a heavy-tailed distribution. Understanding user access patterns is good for WebGIS providers and supports better operational decision-making, and helpful for developers when optimizing WebGIS system architecture and deployment, so as to improve the user experience and to expand the popularity of WebGIS.

  4. Context-based user grouping for multi-casting in heterogeneous radio networks

    Science.gov (United States)

    Mannweiler, C.; Klein, A.; Schneider, J.; Schotten, H. D.

    2011-08-01

    Along with the rise of sophisticated smartphones and smart spaces, the availability of both static and dynamic context information has steadily been increasing in recent years. Due to the popularity of social networks, these data are complemented by profile information about individual users. Making use of this information by classifying users in wireless networks enables targeted content and advertisement delivery as well as optimizing network resources, in particular bandwidth utilization, by facilitating group-based multi-casting. In this paper, we present the design and implementation of a web service for advanced user classification based on user, network, and environmental context information. The service employs simple and advanced clustering algorithms for forming classes of users. Available service functionalities include group formation, context-aware adaptation, and deletion as well as the exposure of group characteristics. Moreover, the results of a performance evaluation, where the service has been integrated in a simulator modeling user behavior in heterogeneous wireless systems, are presented.

  5. ENERGY EFFICIENT NETWORK SELECTION USING 802.16G BASED GSM TECHNOLOGY

    Directory of Open Access Journals (Sweden)

    H. Anandakumar

    2014-01-01

    Full Text Available Handover is the mechanism that transfers information from one terminal to another as a user moves through the coverage area of a cellular system. Here the Network selection is the handover decision process between various network environments. This handover decision will be either mobile or network initiated. In 2G GSM handover decision method especially concentrates on Received frequency signals (RFS. Upcoming technologies (3G/4G the number of available networks increase the selection process should evaluate additional factors such as cost, network services, network terminology, system conditions, user and operators performances and needed energy to work in an exceedingly network. In Future networks (IEEE or 4G standards offer facilities such as network routes, handover routing messages, network and client reports, message exchange with handover triggers and handover negotiation. In this study we have a tendency to discuss the utilization of a cost function to perform associate a network selection exploitation information provided by these standards, such as network coverage or network properties. The efficient function provides flexibility to balance the various factors within the network selection, and our research is focused on rising each seamlessness and energy efficiency of the devices in handovers. We have a tendency to evaluate our approach supported usage scenarios over 2G, 3G and 4G GSM networks. Our results show the optimal networks and handovers were generate appropriate times to increase overall network connectivity as compared to traditional network schemes, at the same time optimizing energy consumption of network devices.

  6. Novel virtual user scheme to increase data confidentiality against eavesdropping in OCDMA network

    Institute of Scientific and Technical Information of China (English)

    Vishav Jyoti; R. S. Kaler

    2011-01-01

    We propose a novel technique to increase the confidentiality of an optical code division multiple access (OCDMA) system.A virtual user technique is analyzed and implemented to make an OCDMA system secure.Using this technique,an eavesdropper will never find an isolated authorized user's signal.When authorized users and virtual users transmit data synchronously and asynchronously,network security increases by 25% and 37.5%,respectively.%We propose a novel technique to increase the confidentiality of an optical code division multiple access (OCDMA) system. A virtual user technique is analyzed and implemented to make an OCDMA system secure. Using this technique, an eavesdropper will never find an isolated authorized user's signal. When authorized users and virtual users transmit data synchronously and asynchronously, network security increases by 25% and 37.5%, respectively.

  7. 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.

  8. Ultra wideband technology for wireless sensor networks

    Science.gov (United States)

    Wang, Yue; Xiong, Weiming

    2011-08-01

    Wireless sensor networks (WSNs) have emerged as an important method for planetary surface exploration. To investigate the optimized wireless technology for WSNs, we summarized the key requirements of WSNs and justified ultra wideband (UWB) technology by comparing with other competitive wireless technologies. We also analyzed network topologies as well as physical and MAC layer designs of IEEE 802.15.4a standard, which adopted impulse radio UWB (IR-UWB) technology. Our analysis showed that IR-UWB-based 802.15.4a standard could enable robust communication, precise ranging, and heterogeneous networking for WSNs applications. The result of our present work implies that UWB-based WSNs can be applied to future planetary surface exploration.

  9. 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.

  10. 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.

  11. 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

  12. 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

  13. 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.

  14. 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.

  15. 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

  16. MSFC institutional area network and ATM technology

    Science.gov (United States)

    Amin, Ashok T.

    1994-10-01

    The New Institutional Area Network (NEWIAN) at Marshall supports over 5000 end users with access to 26 file servers providing work presentation services. It is comprised of some 150 Ethernet LAN's interconnected by bridges/routers which are in turn connected to servers over two dual FDDI rings. The network supports various higher level protocols such as IP, IPX, AppleTalk (AT), and DECNet. At present IPX and AT protocols packets are routed, and IP protocol packets are bridged; however, work is in progress to route all IP packets. The impact of routing IP packets on network operation is examined. Broadband Integrated Services Data Network (BISDN), presently at various stages of development, is intended to provide voice, video, and data transfer services over a single network. BISDN will use asynchronous transfer mode (ATM) as a data transfer technique which provides for transmission, multiplexing, switching, and relaying of small size data units called cells. Limited ATM Wide Area Network (WAN) services are offered by Wiltel, AT&T, Sprint, and others. NASA is testing a pilot ATM WAN with a view to provide Program Support Communication Network services using ATM. ATM supports wide range of data rates and quality of service requirements. It is expected that ATM switches will penetrate campus networks as well. However, presently products in these areas are at various stages of development and standards are not yet complete. We examine development of ATM to help assess its role in the evolution of NEWIAN.

  17. 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...

  18. 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.

  19. Network Speech Systems Technology Program.

    Science.gov (United States)

    1980-09-30

    that this algorithm offers a high degree of adaptability in the face of severe congestion or network damage, coupled with fast and effective performance...shown in 1, ig. 111-7. It ut i’lies thle sane equipment as the speech concent rator: a PI)l’-1 t/44 minicort puter; two I %I( -/ 5g .s (Zho5 in ic ro

  20. 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.

  1. PERFORMANCE ANALYSIS OF USER FAIR-BASED RELAY ADAPTIVE POWER ALLOCATION IN PHYSICAL-LAYER NETWORK CODING COOPERATION

    Institute of Scientific and Technical Information of China (English)

    Cheng Yulun; Yang Longxiang

    2012-01-01

    Network Coding (NC) is an effective technology to enhance the cooperative system spectral efficiency.However,since it is network-oriented,the existing performance metric of single-user outage can not comprehensively evaluate its gain and the impact to the entire network,which affect the user fairness.This paper proposes two novel user fair-based adaptive relay power allocation algorithms in single-relay NC cooperative multiple access channels.Firstly,common outage probability is employed as the performance metric,and to minimize it,a specific condition is deduced.On this basis,the instantaneous channel information-based adaptive relay power allocation scheme and the channel statistic information-based one with lower complexity are designed respectively,which make users' signals superimposed at accurately calculated proportion to maintain fairness.Simulation results show that compared with other existing schemes,the proposed schemes can best maintain user fairness,and effectively improve the common outage performance of the whole system,at the expense of small spectral efficiency.

  2. 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.

  3. How to Maximize User Satisfaction Degree in Multi-service IP Networks

    CERN Document Server

    Nguyen, Huy; Choi, Deokjai

    2010-01-01

    Bandwidth allocation is a fundamental problem in communication networks. With current network moving towards the Future Internet model, the problem is further intensified as network traffic demanding far from exceeds network bandwidth capability. Maintaining a certain user satisfaction degree therefore becomes a challenge research topic. In this paper, we deal with the problem by proposing BASMIN, a novel bandwidth allocation scheme that aims to maximize network user's happiness. We also defined a new metric for evaluating network user satisfaction degree: network worth. A three-step evaluation process is then conducted to compare BASMIN efficiency with other three popular bandwidth allocation schemes. Throughout the tests, we experienced BASMIN's advantages over the others; we even found out that one of the most widely used bandwidth allocation schemes, in fact, is not effective at all.

  4. User Generated Content Consumption and Social Networking in Knowledge-Sharing OSNs

    Science.gov (United States)

    Lussier, Jake T.; Raeder, Troy; Chawla, Nitesh V.

    Knowledge-sharing online social networks are becoming increasingly pervasive and popular. While the user-to-user interactions in these networks have received substantial attention, the consumption of user generated content has not been studied extensively. In this work, we use data gathered from digg.com to present novel findings and draw important sociological conclusions regarding the intimate relationship between consumption and social networking. We first demonstrate that individuals' consumption habits influence their friend networks, consistent with the concept of homophily. We then show that one's social network can also influence the consumption of a submission through the activation of an extended friend network. Finally, we investigate the level of reciprocity, or balance, in the network and uncover relationships that are significantly less balanced than expected.

  5. Advanced Communication and Networking Technologies for Mars Exploration

    Science.gov (United States)

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

    2001-01-01

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

  6. 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.

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

    Science.gov (United States)

    2013-03-21

    ... award under the Rural Health Information Technology Network Development Grant (RHITND) to Grace... relinquishing its fiduciary responsibilities for the Rural Health Information Technology Network Development... HUMAN SERVICES Health Resources and Services Administration Rural Health Information Technology...

  8. A Survey of Key Technology of Network Public Opinion Analysis

    Directory of Open Access Journals (Sweden)

    Li Su Ying

    2016-01-01

    Full Text Available The internet has become an important base for internet users to make comments because of its interactivity and fast dissemination. The outbreak of internet public opinion has become a major risk for network information security. Domestic and foreign researchers had carried out extensive and in-depth study on public opinion. Fruitful results have achieved in the basic theory research and emergency handling and other aspects of public opinion. But research on the public opinion in China is still in the initial stage, the key technology of the public opinion analysis is still as a starting point for in-depth study and discussion.

  9. 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...

  10. 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.

  11. Barriers and Facilitators to Community Mobility for Assistive Technology Users

    Directory of Open Access Journals (Sweden)

    Natasha Layton

    2012-01-01

    Full Text Available Mobility is frequently described in terms of individual body function and structures however contemporary views of disability also recognise the role of environment in creating disability. Aim. To identify consumer perspectives regarding barriers and facilitators to optimal mobility for a heterogeneous population of impaired Victorians who use assistive technology in their daily lives. Method. An accessible survey investigated the impact of supports or facilitators upon actual and desired life outcomes and health-related quality of life, from 100 AT users in Victoria, Australia. This paper reports upon data pertaining to community mobility. Results. A range of barriers and enablers to community mobility were identified including access to AT devices, environmental interventions, public transport, and inclusive community environs. Substantial levels of unmet need result in limited personal mobility and community participation. Outcomes fall short of many principles enshrined in current policy and human rights frameworks. Conclusion. AT devices as well as accessible and inclusive home and community environs are essential to maximizing mobility for many. Given the impact of the environment upon the capacity of individuals to realise community mobility, this raises the question as to whether rehabilitation practitioners, as well as prescribing AT devices, should work to build accessible communities via systemic advocacy.

  12. 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

  13. 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

  14. 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...

  15. 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.

  16. 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).

  17. Autonomous vision networking: miniature wireless sensor networks with imaging technology

    Science.gov (United States)

    Messinger, Gioia; Goldberg, Giora

    2006-09-01

    The recent emergence of integrated PicoRadio technology, the rise of low power, low cost, System-On-Chip (SOC) CMOS imagers, coupled with the fast evolution of networking protocols and digital signal processing (DSP), created a unique opportunity to achieve the goal of deploying large-scale, low cost, intelligent, ultra-low power distributed wireless sensor networks for the visualization of the environment. Of all sensors, vision is the most desired, but its applications in distributed sensor networks have been elusive so far. Not any more. The practicality and viability of ultra-low power vision networking has been proven and its applications are countless, from security, and chemical analysis to industrial monitoring, asset tracking and visual recognition, vision networking represents a truly disruptive technology applicable to many industries. The presentation discusses some of the critical components and technologies necessary to make these networks and products affordable and ubiquitous - specifically PicoRadios, CMOS imagers, imaging DSP, networking and overall wireless sensor network (WSN) system concepts. The paradigm shift, from large, centralized and expensive sensor platforms, to small, low cost, distributed, sensor networks, is possible due to the emergence and convergence of a few innovative technologies. Avaak has developed a vision network that is aided by other sensors such as motion, acoustic and magnetic, and plans to deploy it for use in military and commercial applications. In comparison to other sensors, imagers produce large data files that require pre-processing and a certain level of compression before these are transmitted to a network server, in order to minimize the load on the network. Some of the most innovative chemical detectors currently in development are based on sensors that change color or pattern in the presence of the desired analytes. These changes are easily recorded and analyzed by a CMOS imager and an on-board DSP processor

  18. 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…

  19. PERFORMANCE OF MULTI SERVER AUTHENTICATION AND KEY AGREEMENT WITH USER PROTECTION IN NETWORK SECURITY

    Directory of Open Access Journals (Sweden)

    NAGAMALLESWARA RAO.DASARI,

    2010-08-01

    Full Text Available Using smart cards, remote user authentication and key agreement can be simplified, flexible, and efficient for creating a secure distributed computers environment. Addition to user authenticationand key distribution, it is very useful for providing identity privacy for users. In this paper, we propose novel multi server authentication and key agreement schemes with user protection in network security. We first propose a single-server scheme and then apply this scheme to a multi-server environment. The main meritsinclude: (1 The privacy of users can be ensured; (2 a user canfreely choose his own password; (3 the computation and communication cost is very low; (4 servers and users can authenticate each other; (5 it generates a session key agreed by the server and the user; (6 our proposed schemes are Nonce-based schemes which does not have aserious time synchronization problem.

  20. 76 FR 58020 - Prescription Drug User Fee Act IV Information Technology Plan

    Science.gov (United States)

    2011-09-19

    ... HUMAN SERVICES Food and Drug Administration Prescription Drug User Fee Act IV Information Technology... exchange, review, and management of information supporting the process for the review of human drug... Drug User Fee Act (PDUFA) IV Information Technology Plan'' (June 2008 plan). This updated plan...

  1. Quantum Key Distribution in a Multi-User Network at Gigahertz Clock rates

    CERN Document Server

    Fernández, V; Collins, R J; Townsend, P D; Cova, S D; Rech, I; Buller, G S; Fernandez, Veronica; Gordon, Karen J.; Collins, Robert J.; Townsend, Paul D.; Cova, Sergio D.; Rech, Ivan; Buller, Gerald S.

    2005-01-01

    In recent years quantum information research has lead to the discovery of a number of remarkable new paradigms for information processing and communication. These developments include quantum cryptography schemes that offer unconditionally secure information transport guaranteed by quantum-mechanical laws. Such potentially disruptive security technologies could be of high strategic and economic value in the future. Two major issues confronting researchers in this field are the transmission range (typically <100km) and the key exchange rate, which can be as low as a few bits per second at long optical fiber distances. This paper describes further research of an approach to significantly enhance the key exchange rate in an optical fiber system at distances in the range of 1-20km. We will present results on a number of application scenarios, including point-to-point links and multi-user networks. Quantum key distribution systems have been developed, which use standard telecommunications optical fiber, and whi...

  2. How wireless technology can work for service users.

    Science.gov (United States)

    Barron, Derek; Fleming, Mark

    2010-05-01

    More than two years ago, NHS Ayrshire and Arran introduced a wireless system for recording patient details and views. As a result, nurses can spend the time they used to spend writing up notes with service users. This article describes the system and an audit of staff and service user opinion before and after it was introduced.

  3. Synthesis Report on User Acceptability of Ventilation Technologies

    DEFF Research Database (Denmark)

    Larsen, Olena Kalyanova; Heiselberg, Per

    This report is prepared to summarise user satisfaction surveys available for 18 buildings in Building AdVent project. The results of user satisfaction survey are assembled in Building AdVent project D7 report for the Work Package 3. These serve a background for further discussions of acceptability...

  4. 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...

  5. Technology network for machine tools in Vietnam

    OpenAIRE

    Mizuno, Junko

    2012-01-01

    When Vietnam joined the WTO, it accepted foreign direct investment and started to grow. Technically, it was then greatly influenced by the enterprises that entered the country through direct investment. This report shows that the technology network for machine tools is formed via direct investment and subcontracting.

  6. 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

  7. 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…

  8. Enabling Technologies for Cognitive Optical Networks

    DEFF Research Database (Denmark)

    Borkowski, Robert

    to technologies required for their implementation. Operation of CON-enabling machine learning methods is tested experimentally and DSP-based OPM techniques for software-defined receivers are introduced and verified. The presented set of technologies forms a foundation, upon which next generation fiber-optic data......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...

  9. 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.

  10. Performance Analysis of User Pairing Algorithm in Full-Duplex Cellular Networks

    Directory of Open Access Journals (Sweden)

    Wonjong Noh

    2017-01-01

    Full Text Available In a full duplexing (FD wireless cellular network, a base station operates in FD mode, while the downlink (DL and uplink (UL users operate in half duplexing (HD mode. Thus, the downlink and uplink transmissions occur simultaneously so that interuser interference from a UL to a DL user occurs. In an FD network, the main challenge to minimize the interuser interference is user pairing, which determines a pair of DL and UL users who use the same radio resource simultaneously. We formulate a nonconvex optimization problem for user pairing to maximize the cell throughput. Then, we propose a heuristic user pairing algorithm with low complexity. This algorithm is designed such that the DL user having a better signal quality has higher priority to choose its paired UL user for throughput maximization. Thereafter, we conduct theoretical performance analysis of the FD cellular system based on stochastic geometry and analyze the impact of the user paring algorithm on the performance of the FD cellular system. Results show that the FD system that uses the proposed user pairing algorithm effectively reduces the interuser interference and approaches optimal performance. It also considerably outperforms the FD system using a random user pairing and almost doubles the conventional HD system in terms of cell throughput.

  11. Social Networking and Online Privacy: Facebook Users' Perceptions

    National Research Council Canada - National Science Library

    Deirdre O'Brien; Ann M Torres

    2012-01-01

    This study investigates Facebook users' perceptions of online privacy, exploring their awareness of privacy issues and how their behaviour is influenced by this awareness, as well as the role of trust...

  12. Network Control Center User Planning System (NCC UPS)

    Science.gov (United States)

    Dealy, Brian

    1991-01-01

    NCC UPS is presented in the form of the viewgraphs. The following subject areas are covered: UPS overview; NCC UPS role; major NCC UPS functional requirements; interactive user access levels; UPS interfaces; interactive user subsystem; interface navigation; scheduling screen hierarchy; interactive scheduling input panels; autogenerated schedule request panel; schedule data tabular display panel; schedule data graphic display panel; graphic scheduling aid design; and schedule data graphic display.

  13. User satisfaction-based quality evaluation model and survey analysis of network information service

    Institute of Scientific and Technical Information of China (English)

    LEI; Xue; JIAO; Yuying

    2009-01-01

    On the basis of user satisfaction,authors made research hypotheses by learning from relevant e-service quality evaluation models.A questionnaire survey was then conducted on some content-based websites in terms of their convenience,information quality,personalization and site aesthetics,which may affect the overall satisfaction of users.Statistical analysis was also made to build a user satisfaction-based quality evaluation system of network information service.

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

    OpenAIRE

    MARÍA-DEL-CARMEN eALARCÓN-DEL-AMO; MIGUEL-ÁNGEL eGÓMEZ-BORJA; CARLOTA eLORENZO-ROMERO

    2015-01-01

    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-d...

  15. 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...

  16. Real Time Synchronization of Live Broadcast Streams with User Generated Content and Social Network Streams

    NARCIS (Netherlands)

    Stokking, H.M.; Kaptein, A.M.; Veenhuizen, A.T.; Spitters4, M.M.; Niamut, O.A.

    2013-01-01

    This paper describes the work in the FP7 STEER project on augmenting a live broadcast with live user generated content. This user generated content consists of both video content, captured with mobile devices, and social network content, such as Facebook or Twitter messages. To enable multi-source s

  17. 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

  18. 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...

  19. 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 ......, as virality is very important in social networks, we will describe the viral elements of Gedda-Headz. We will also introduce the Gedda-Headz spreader, a novel method to spread the word about the network, increasing the virality further....

  20. 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.

  1. Faculty and Student Use of Technologies, User Productivity, and User Preference in Distance Education

    Science.gov (United States)

    Zhao, Jensen J.; Alexander, Melody W.; Perreault, Heidi; Waldman, Lila; Truell, Allen D.

    2009-01-01

    The authors surveyed faculty and students in Association to Advance Collegiate Schools of Business-accredited U.S. business colleges on their use of information technologies in distance education and their perceptions of the technologies' effect on productivity and technology preference. The authors collected data from 140 professors across the…

  2. Developing a Framework and Implementing User-Driven Innovation in Supply and Value Network

    DEFF Research Database (Denmark)

    Jacobsen, Alexia; Lassen, Astrid Heidemann; Wandahl, Søren

    2011-01-01

    This paper serves to create a framework for and, subsequently, implementing user-driven innovation in a construction material industry network. The research has its outset in Project InnoDoors that consists of a Danish university and a construction material network. The framework and the implemen...

  3. 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.

  4. Breaking conversational norms on a Portuguese users' network

    DEFF Research Database (Denmark)

    Oliveira, Sandi Michele de

    2007-01-01

    Abstract of book Two thirds of global internet users are non-English speakers. Despite this, most scholarly literature on the internet and computer-mediated-communication (CMC) focuses exclusively on English. This is the first book devoted to analyzing internet related CMC in languages other than...

  5. 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.

  6. 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.

  7. Enhancing User Support in Open Problem Solving Environments through Bayesian Network Inference Techniques

    Science.gov (United States)

    Tselios, Nikolaos; Stoica, Adrian; Maragoudakis, Manolis; Avouris, Nikolaos; Komis, Vassilis

    2006-01-01

    During the last years, development of open learning environments that support effectively their users has been a challenge for the research community of educational technologies. The open interactive nature of these environments results in users experiencing difficulties in coping with the plethora of available functions, especially during their…

  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. The Synergism of User Needs, System Requirements, and Technological Limitations.

    Science.gov (United States)

    Levine, Gwen R.

    User perception of data importance and the economic feasibility of hardware and storage devices will determine the future direction of online systems. A retrieval system's functions are ultimately dictated by database design. Early online sytems were designed for bibliographic information limited to citations only using sequential files. When…

  10. Big-Five Personality Prediction Based on User Behaviors at Social Network Sites

    CERN Document Server

    Bai, Shuotian; Cheng, Li

    2012-01-01

    Many customer services are already available at Social Network Sites (SNSs), including user recommendation and media interaction, to name a few. There are strong desires to provide online users more dedicated and personalized services that fit into individual's need, usually strongly depending on the inner personalities of the user. However, little has been done to conduct proper psychological analysis, crucial for explaining the user's outer behaviors from their inner personality. In this paper, we propose an approach that intends to facilitate this line of research by directly predicting the so called Big-Five Personality from user's SNS behaviors. Comparing to the conventional inventory-based psychological analysis, we demonstrate via experimental studies that users' personalities can be predicted with reasonable precision based on their online behaviors. Except for proving some former behavior-personality correlation results, our experiments show that extraversion is positively related to one's status rep...

  11. 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.

  12. 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.

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

    Science.gov (United States)

    Gonçalves, Bruno; Perra, Nicola; Vespignani, Alessandro

    2011-01-01

    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.

  14. 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.

  15. The rise and fall of self-service in Amsterdam trams: User technology relations in a case of service innovation

    NARCIS (Netherlands)

    Nahuis, Roel

    2009-01-01

    The stabilisation of innovative technology depends on reconciling technological opportunities and user behaviour. This can be achieved by adjusting the technology to the users, by configuring the user, or by a combination thereof. This paper evaluates different strategies in a case of service innova

  16. Online Networks as Societies: User Behaviors and Contribution Incentives

    NARCIS (Netherlands)

    Jia, L.

    2013-01-01

    Online networks like email, Facebook, LinkedIn, Wikipedia, eBay, and BitTorrent-like Peer-to-Peer (P2P) systems have become popular and powerful infrastructures for communication. They involve potentially large numbers of humans with their collective inputs and decisions, and they often rely on the

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

    NARCIS (Netherlands)

    Lorenzo-Romero, C.; Constantinides, E.; 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 beg

  18. Online Networks as Societies: User Behaviors and Contribution Incentives

    NARCIS (Netherlands)

    Jia, L.

    2013-01-01

    Online networks like email, Facebook, LinkedIn, Wikipedia, eBay, and BitTorrent-like Peer-to-Peer (P2P) systems have become popular and powerful infrastructures for communication. They involve potentially large numbers of humans with their collective inputs and decisions, and they often rely on the

  19. Dynamic Trust Models between Users over Social Networks

    Science.gov (United States)

    2016-03-30

    model, we consider introducing some trust discount factors. The simplest one is an exponential discount factor defined by ρ(Δt; λ) = exp(−λΔt), where...the Cosmetics review dataset. The other one is composed of review records collected from “anikore”, a ranking and review site for anime , which is...referred to as the Anime review dataset. In both the datasets, each record has 4-triple (u, i, s, t), which means user u gives a score s to item i at

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

    Directory of Open Access Journals (Sweden)

    Stephen M. Mutula

    2013-02-01

    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.

  1. 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.

  2. 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.

  3. Queuing Game Theory Based Optimal Routing Scheme for Heterogeneous Users over Space Information Networks

    Directory of Open Access Journals (Sweden)

    Chao Guo

    2017-01-01

    Full Text Available An optimal routing scheme in space information networks was presented to balance network loads for heterogeneous users. According to the competition among the nodes, the model was built based on queuing game theory. The virtual routing platform was in charge of resources allocation and route selection. It got user’s gain to decide which node the user joined in. Owning to the existing of heterogeneous users, an optimal admission fee needed to be obtained to avoid congestion. In our model, firstly, the whole welfare of the system was formulated. Then the optimal admission fee was calculated through maximizing the whole welfare. Meanwhile, the average maximum queue length was generated to set the buffer space of the node. At last, a routing factor was introduced into the route algorithm in order that the optimal routing could be selected by heterogeneous users. As a result, the system welfare reaches the maximum.

  4. Socio-contextual Network Mining for User Assistance in Web-based Knowledge Gathering Tasks

    Science.gov (United States)

    Rajendran, Balaji; Kombiah, Iyakutti

    Web-based Knowledge Gathering (WKG) is a specialized and complex information seeking task carried out by many users on the web, for their various learning, and decision-making requirements. We construct a contextual semantic structure by observing the actions of the users involved in WKG task, in order to gain an understanding of their task and requirement. We also build a knowledge warehouse in the form of a master Semantic Link Network (SLX) that accommodates and assimilates all the contextual semantic structures. This master SLX, which is a socio-contextual network, is then mined to provide contextual inputs to the current users through their agents. We validated our approach through experiments and analyzed the benefits to the users in terms of resource explorations and the time saved. The results are positive enough to motivate us to implement in a larger scale.

  5. Wireless sensor and actuator networks for lighting energy efficiency and user satisfaction

    Science.gov (United States)

    Wen, Yao-Jung

    Buildings consume more than one third of the primary energy generated in the U.S., and lighting alone accounts for approximately 30% of the energy usage in commercial buildings. As the largest electricity consumer of all building electrical systems, lighting harbors the greatest potential for energy savings in the commercial sector. Fifty percent of current energy consumption could be reduced with energy-efficient lighting management strategies. While commercial products do exist, they are poorly received due to exorbitant retrofitting cost and unsatisfactory performance. As a result, most commercial buildings, especially legacy buildings, have not taken advantage of the opportunity to generate savings from lighting. The emergence of wireless sensor and actuator network (WSAN) technologies presents an alternative that circumvents costly rewiring and promises better performance than existing commercial lighting systems. The goal of this dissertation research is to develop a framework for wireless-networked lighting systems with increased cost effectiveness, energy efficiency, and user satisfaction. This research is realized through both theoretical developments and implementations. The theoretical research aims at developing techniques for harnessing WSAN technologies to lighting hardware and control strategies. Leveraging redundancy, a sensor validation and fusion algorithm is developed for extracting pertinent lighting information from the disturbance-prone desktop-mounted photosensors. An adaptive sensing strategy optimizes the timing of data acquisition and power-hungry wireless transmission of sensory feedback in real-time lighting control. Exploiting the individual addressability of wireless-enabled luminaires, a lighting optimization algorithm is developed to create the optimal lighting that minimizes energy usage while satisfying occupants' diverse lighting preferences. The wireless-networked lighting system was implemented and tested in a number of real

  6. The European ALMA Regional Centre Network: A Geographically Distributed User Support Model

    CERN Document Server

    Hatziminaoglou, Evanthia; Andreani, Paola; Barta, Miroslav; Bertoldi, Frank; Brand, Jan; Gueth, Frederique; Hogerheijde, Michiel; Maercker, Matthias; Massardi, Marcella; Muehle, Stefanie; Muxlow, Thomas; Richards, Anita; Schilke, Peter; Tilanus, Remo; Vlemmings, Wouter; Afonso, Jose; Messias, Hugo

    2016-01-01

    In recent years there has been a paradigm shift from centralised to geographically distributed resources. Individual entities are no longer able to host or afford the necessary expertise in-house, and, as a consequence, society increasingly relies on widespread collaborations. Although such collaborations are now the norm for scientific projects, more technical structures providing support to a distributed scientific community without direct financial or other material benefits are scarce. The network of European ALMA Regional Centre (ARC) nodes is an example of such an internationally distributed user support network. It is an organised effort to provide the European ALMA user community with uniform expert support to enable optimal usage and scientific output of the ALMA facility. The network model for the European ARC nodes is described in terms of its organisation, communication strategies and user support.

  7. Mobile user forecast and power-law acceleration invariance of scale-free networks

    Institute of Scientific and Technical Information of China (English)

    Guo Jin-Li; Guo Zhao-Hua; Liu Xue-Jiao

    2011-01-01

    This paper studies and predicts the number growth of China's mobile users by using the power-law regression.We find that the number growth of the mobile users follows a power law.Motivated by the data on the evolution of the mobile users,we consider scenarios of self-organization of accelerating growth networks into scale-free structures and propose a directed network model,in which the nodes grow following a power-law acceleration.The expressions for the transient and the stationary average degree distributions are obtained by using the Poisson process.This result shows that the model generates appropriate power-law connectivity distributions.Therefore,we find a power-law acceleration invariance of the scale-free networks.The numerical simulations of the models agree with the analytical results well.

  8. Photonic technology for switched rf avionics networks

    Science.gov (United States)

    Hamilton, Michael C.; Thaniyavarn, Suwat; Abbas, Gregory L.; LaGasse, Michael J.; Traynor, Timothy; Lin, Jack P.

    1997-10-01

    The application of photonics technology in switched RF networks is discussed with emphasis on the benefits for avionics applications. System requirements and performance issues are addressed. A 16 X 16 photonic switch module prototype is described and results for RF fiber-optic links passing through the module are presented. RF channel isolation measured was at least 75 dB. A demonstration is described in which a photonic network using the switch module passed signals from a dynamic electromagnetic environment simulator to two radar warning systems under test. Demonstration modes included simulation of both aperture sharing and processor sharing. Finally, a novel alternative switch module architecture is described that is strictly non-blocking and has inherently better channel isolation.

  9. User Expectations for Media Sharing Practices in Open Display Networks.

    Science.gov (United States)

    Jose, Rui; Cardoso, Jorge C S; Hong, Jason

    2015-07-06

    Open Display Networks have the potential to allow many content creators to publish their media to an open-ended set of screen displays. However, this raises the issue of how to match that content to the right displays. In this study, we aim to understand how the perceived utility of particular media sharing scenarios is affected by three independent variables, more specifically: (a) the locativeness of the content being shared; (b) how personal that content is and (c) the scope in which it is being shared. To assess these effects, we composed a set of 24 media sharing scenarios embedded with different treatments of our three independent variables. We then asked 100 participants to express their perception of the relevance of those scenarios. The results suggest a clear preference for scenarios where content is both local and directly related to the person that is publishing it. This is in stark contrast to the types of content that are commonly found in public displays, and confirms the opportunity that open displays networks may represent a new media for self-expression. This novel understanding may inform the design of new publication paradigms that will enable people to share media across the display networks.

  10. 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.

  11. 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

  12. Security technologies and protocols for Asynchronous Transfer Mode networks

    Energy Technology Data Exchange (ETDEWEB)

    Tarman, T.D.

    1996-06-01

    Asynchronous Transfer Mode (ATM) is a new data communications technology that promises to integrate voice, video, and data traffic into a common network infrastructure. In order to fully utilize ATM`s ability to transfer real-time data at high rates, applications will start to access the ATM layer directly. As a result of this trend, security mechanisms at the ATM layer will be required. A number of research programs are currently in progress which seek to better understand the unique issues associated with ATM security. This paper describes some of these issues, and the approaches taken by various organizations in the design of ATM layer security mechanisms. Efforts within the ATM Forum to address the user communities need for ATM security are also described.

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

    Directory of Open Access Journals (Sweden)

    Skiba S. A.

    2015-03-01

    Full Text Available 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. The article presents the first part of the work, which includes the decision of 3 objectives, namely to obtain quantitative, statistical data on the properties of consumer preferences of users of the social network "VKontakte"; identifying groups of consumers with different severity of socio-psychological properties of preferences; definition of psycho type of user with a set of inherent characteristics and behavior patterns. To achieve the objectives we developed comprehensive software, called "MindScore", with main components at this stage - 1 the module for user authorization through the app of social network "VKontakte" and for extraction data of its social profile, 2 the module for processing and analysis data. In the study we have given rise to the creation of unique algorithms for personality mining using dataset of user profile social network

  14. Crowdsourcing User-Generated Mobile Sensor Weather Data for Densifying Static Geosensor Networks

    Directory of Open Access Journals (Sweden)

    Shay Sosko

    2017-02-01

    Full Text Available Static geosensor networks are comprised of stations with sensor devices providing data relevant for monitoring environmental phenomena in their geographic perimeter. Although early warning systems for disaster management rely on data retrieved from these networks, some limitations exist, largely in terms of insufficient coverage and low density. Crowdsourcing user-generated data is emerging as a working methodology for retrieving real-time data in disaster situations, reducing the aforementioned limitations, and augmenting with real-time data generated voluntarily by nearby citizens. This paper explores the use of crowdsourced user-generated sensor weather data from mobile devices for the creation of a unified and densified geosensor network. Different scenario experiments are adapted, in which weather data are collected using smartphone sensors, integrated with the development of a stabilization algorithm, for determining the user-generated weather data reliability and usability. Showcasing this methodology on a large data volume, a spatiotemporal algorithm was developed for filtering on-line user-generated weather data retrieved from WeatherSignal, and used for simulation and assessment of densifying the static geosensor weather network of Israel. Geostatistical results obtained proved that, although user-generated weather data show small discrepancies when compared to authoritative data, with considerations they can be used alongside authoritative data, producing a densified and augmented weather map that is detailed and continuous.

  15. 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.

  16. 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

    . Research among children is very scarce in this particular domain. Our statistical analyses based on hierarchical linear modeling reveal two general results: First, lead users among children appear to possess a variety of links between clusters. Second, opinion leaders are locally positioned within clusters......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...

  17. 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.

  18. Multi-user cognitive radio network resource allocation based on the adaptive niche immune genetic algorithm

    Institute of Scientific and Technical Information of China (English)

    Zu Yun-Xiao; Zhou Jie

    2012-01-01

    Multi-user cognitive radio network resource allocation based on the adaptive niche immune genetic algorithm is proposed,and a fitness function is provided.Simulations are conducted using the adaptive niche immune genetic algorithm,the simulated annealing algorithm,the quantum genetic algorithm and the simple genetic algorithm,respectively.The results show that the adaptive niche immune genetic algorithm performs better than the other three algorithms in terms of the multi-user cognitive radio network resource allocation,and has quick convergence speed and strong global searching capability,which effectively reduces the system power consumption and bit error rate.

  19. Multi-user cognitive radio network resource allocation based on the adaptive niche immune genetic algorithm

    Science.gov (United States)

    Zu, Yun-Xiao; Zhou, Jie

    2012-01-01

    Multi-user cognitive radio network resource allocation based on the adaptive niche immune genetic algorithm is proposed, and a fitness function is provided. Simulations are conducted using the adaptive niche immune genetic algorithm, the simulated annealing algorithm, the quantum genetic algorithm and the simple genetic algorithm, respectively. The results show that the adaptive niche immune genetic algorithm performs better than the other three algorithms in terms of the multi-user cognitive radio network resource allocation, and has quick convergence speed and strong global searching capability, which effectively reduces the system power consumption and bit error rate.

  20. Factors influencing knowledge contribution:An empirical investigation of social networking website users

    Institute of Scientific and Technical Information of China (English)

    Shengli; DENG; Ting; ZHOU; Min; ZHANG

    2012-01-01

    Purpose:In the Web 2.0 era,leveraging the collective power of user knowledge contributions has become an important part of the study of collective intelligence.This research aims to investigate the factors which influence knowledge contribution behavior of social networking sites(SNS)users.Design/methodology/approach:The data were obtained from an online survey of 251 social networking sites users.Structural equation modeling analysis was used to validate the proposed model.Findings:Our survey shows that the individuals’motivation for knowledge contribution,their capability of contributing knowledge,interpersonal trust and their own habits positively influence their knowledge contribution behavior,but reward does not significantly influence knowledge contribution in the online virtual community.Research limitations:Respondents of our online survey are mainly undergraduate and graduate students.A limited sample group cannot represent all of the population.A larger survey involving more SNS users may be useful.Practical implications:The results have provided some theoretical basis for promoting knowledge contribution and user viscosity.Originality/value:Few studies have investigated the impact of social influence and user habits on knowledge contribution behavior of SNS users.This study can make a theoretical contribution by examining how the social influence processes and habits affect one’s knowledge contribution behavior using online communities.

  1. 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.

  2. Data Throughput Evaluation of Internet Users over UMTS Wireless Network

    Directory of Open Access Journals (Sweden)

    Paiiz Azmi

    2007-12-01

    Full Text Available Although voice is a mandatory service in the wireless telecommunication networks, most of new data services are based on Internet. These services include http, telnet, SMTP, etc. In addition, mobile channel is a multipath fading channel. TCP/IP performance in the wired systems depends on the link congestion and packet loss. In this paper we study how TCP/P protocol is used in UMTS and survey its performance reduction in a multipath fading channel alone and with an ARQ protocol.

  3. 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, ...

  4. Health Information Technology Systems profoundly impact users: a case study in a dental school.

    Science.gov (United States)

    Hill, Heather K; Stewart, Denice C L; Ash, Joan S

    2010-04-01

    The purpose of this study was to increase our understanding of the impact of Health Information Technology Systems (HITS) on dental school users when the systems are integrated into chair-side patient care. We used qualitative research methods, including interviews, focus groups, and observations, to capture the experiences of HITS users at a single institution. Users included administrators, clinical faculty members, predoctoral students, support staff, and residents. The data were analyzed using a grounded theory approach, and nine themes emerged: 1) HITS benefits were disproportionate among users; 2) communicating about the HITS was challenging; 3) users experienced a range of strong emotions; 4) the instructor persona diminished; 5) there were shifts in the school's power structure; 6) allocation of end-users' time shifted; 7) the training and support needs of end-users were significant; 8) perceived lack of HITS usability made documentation cumbersome for clinicians; and 9) clinicians' workflow was disrupted. HITS integration into patient care impacts the work of all system users, especially end-users. The themes highlight areas of potential concern for implementers and users in integrating a HITS into patient care.

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

    OpenAIRE

    Muhammad Jasim; Imran,; Yaser

    2016-01-01

    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 d...

  6. 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…

  7. [Design and application of user managing system of cardiac remote monitoring network].

    Science.gov (United States)

    Chen, Shouqiang; Zhang, Jianmin; Yuan, Feng; Gao, Haiqing

    2007-12-01

    According to inpatient records, data managing demand of cardiac remote monitoring network and computer, this software was designed with relative database ACCESS. Its interface, operational button and menu were designed in VBA language assistantly. Its design included collective design, amity, practicability and compatibility. Its function consisted of registering, inquiring, statisticing and printing, et al. It could be used to manage users effectively and could be helpful to exerting important action of cardiac remote monitoring network in preventing cardiac-vascular emergency ulteriorly.

  8. 11th Annual CMMI Technology Conference and User Group

    Science.gov (United States)

    2011-11-17

    Change Management Team - Responsibilities Vision Dialogue Resources Congruence Anticipation Empowerment Transition Alignment Change...maintenance and disease prevention/treatment • Several areas of study: computer science, software/ systems engineering, IT, HCI , social dynamics...market needs to happen very quickly Source: SEI HCI : Human Computer Interaction; AI: Artificial intelligence 24 11th Annual CMMI ® Technology

  9. Broadband access technology for passive optical network

    Science.gov (United States)

    Chi, Sien; Yeh, Chien-Hung; Chow, Chi-Wai

    2009-01-01

    We will introduce four related topics about fiber access network technologies for PONs. First, an upstream signal powerequalizer is proposed and designed using a FP-LD in optical line terminal applied to the TDM-PON, and a 20dB dynamic upstream power range from -5 to -25dBm having a 1.7dB maximal power variation is retrieved. The fiber-fault protection is also an important issue for PON. We investigate a simple and cost-effective TDM/WDM PON system with self-protected function. Next, using RSOA-based colorless WDM-PON is also demonstrated. We propose a costeffective CW light source into RSOA for 2.5Gb/s upstream in WDM-PON together with self-healing mechanism against fiber fault. Finally, we investigate a 4Gb/s OFDM-QAM for both upstream and downstream traffic in long-reach WDM/TDM PON system under 100km transmission without dispersion compensation. As a result, we believe that these key access technologies are emerging and useful for the next generation broadband FTTH networks.

  10. A bridge network maintenance framework for Pareto optimization of stakeholders/users costs

    Energy Technology Data Exchange (ETDEWEB)

    Orcesi, Andre D., E-mail: andre.orcesi@lcpc.f [Laboratoire Central des Ponts et Chaussees, Section Durabilite des Ouvrages d' Art, 58 boulevard Lefebvre, F-75732 Paris Cedex 15 (France); Cremona, Christian F., E-mail: Christian.Cremona@developpement-durable.gouv.f [Commissariat General au Developpement Durable, Direction de la recherche et de l' innovation, Tour Pascal B, F-92055, La Defense Cedex (France)

    2010-11-15

    For managing highway bridges, stakeholders require efficient and practical decision making techniques. In a context of limited bridge management budget, it is crucial to determine the most effective breakdown of financial resources over the different structures of a bridge network. Bridge management systems (BMSs) have been developed for such a purpose. However, they generally rely on an individual approach. The influence of the position of bridges in the transportation network, the consequences of inadequate service for the network users, due to maintenance actions or bridge failure, are not taken into consideration. Therefore, maintenance strategies obtained with current BMSs do not necessarily lead to an optimal level of service (LOS) of the bridge network for the users of the transportation network. Besides, the assessment of the structural performance of highway bridges usually requires the access to the geometrical and mechanical properties of its components. Such information might not be available for all structures in a bridge network for which managers try to schedule and prioritize maintenance strategies. On the contrary, visual inspections are performed regularly and information is generally available for all structures of the bridge network. The objective of this paper is threefold (i) propose an advanced network-level bridge management system considering the position of each bridge in the transportation network, (ii) use information obtained at visual inspections to assess the performance of bridges, and (iii) compare optimal maintenance strategies, obtained with a genetic algorithm, when considering interests of users and bridge owner either separately as conflicting criteria, or simultaneously as a common interest for the whole community. In each case, safety and serviceability aspects are taken into account in the model when determining optimal strategies. The theoretical and numerical developments are applied on a French bridge network.

  11. LTE Advanced: Necessities and Technological Challenges for 4th Generation Mobile Network

    Directory of Open Access Journals (Sweden)

    Asad Ali Shaikh

    2012-08-01

    Full Text Available The higher peak data rates for portable users are in demand. Audio/Video streaming, online conferences and community media services are fetching the requirement of life. In order to accomplish the absolute amount of data need of users, vigorous and well-organized wireless technology is needed. The solution for future mobile wireless networks which is based on Rel-10 is LTE-Advanced. It is the promising technology for upcoming wireless broadband network based on Rel-8 of Long term Evolution (LTE. This research paper provides a higher level overview of LTE-Advanced, which includes carrier aggregation for well-organized spectrum use, MIMO techniques for numerous signal transmissions and receptions, relaying and heterogeneous consumption strategy. LTE-Advanced scheme will be the Next Generation wireless technology for years to come.

  12. 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...

  13. [New technologies: support opportunities for network research].

    Science.gov (United States)

    Rodríguez-Martín, A; Novalbos Ruiz, J P; Jiménez-Rodríguez, R; Jiménez-Rodríguez, A

    2012-11-01

    The consolidation of a support area for network research, which promotes collaborative research, training and the dissemination of knowledge through the use of ICTs, requires the organization of a work methodology to share and exchange resources in a specific network that is already running. The establishment of communication mechanisms between researchers from different groups will be necessary along with the introduction of the ICTs in the teaching and advanced environments of research training, different inventories of the research resources that are available for exchanges and shared use between groups and laboratories, and finally, a shared scientific documentation system with the appropriate maintenance of the previously listed tools. Large administrative structures and detailed plans are not needed to comply with all of the above functions. The availability of effective tools, however, to combine efforts and search for resources in all of these areas is needed, with the agility and flexibility that allow us to currently use new communication and information technologies. The results of this research support area should lead to an increase in the efficacy and quality of the network by increasing the flow of information and the inter-group collaboration in teaching, research and professional development, along with the transfer and dissemination of research results.

  14. 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.

  15. 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.

  16. 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.

  17. Opinion Mining for User Generated Design by Social Networking Service and Japanese Manga

    Directory of Open Access Journals (Sweden)

    Anak Agung Gede Dharma

    2013-09-01

    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 XE "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.

  18. Multi-User Cooperative Diversity through Network Coding Based on Classical Coding Theory

    CERN Document Server

    Rebelatto, João Luiz; Li, Yonghui; Vucetic, Branka

    2010-01-01

    In this work, we propose and analyze a generalized construction of distributed network codes for a network consisting of M users sending different information to a common base station through independent block fading channels. The aim is to increase the diversity order of the system without reducing its code rate. The proposed scheme, called generalized dynamic-network codes (GDNC), is a generalization of the dynamic-network codes (DNC) recently proposed by Xiao and Skoglund. The design of the network codes that maximize the diversity order is recognized as equivalent to the design of linear block codes over a nonbinary finite field under the Hamming metric. We prove that adopting a systematic generator matrix of a maximum distance separable block code over a sufficiently large finite field as the network transfer matrix is a sufficient condition for full diversity order under link failure model. The proposed generalization offers a much better tradeoff between rate and diversity order compared to the DNC. An...

  19. 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

  20. ESA New Generation Science Archives: New Technologies Applied to Graphical User Interface Creation

    Science.gov (United States)

    Fernandez, M.; Arviset, C.; Barbarisi, I.; Castellanos, J.; Cheek, N.; Costa, H.; Fajersztejn, N.; Gonzalez, J.; Laruelo, A.; Leon, I.; Ortiz, I.; Osuna, P.; Salgado, J.; Stebe, A.; Tapiador, D.

    2010-12-01

    The Science Archives and VO Team (SAT) has undertaken the effort to build state of the art sub-systems for its new generation of archives. At the time of writing this abstract, the new technology has already been applied to the creation of the SOHO and EXOSAT Science Archive s and will be used to re-engineer some of the already existing ESA Science Archives in the future. The Graphical User Interface sub-system has been designed and developed upon the premises of building a lightweight rich client application to query and retrieve scientific data quickly and efficiently; special attention has been paid to the usability and ergonomics of the interface. The system architecture relies on the Model View Controller pattern, which isolates logic from the graphical interface. Multiple window layout arrangements are possible using a docking windows framework with virtually no limitations (InfoNode). New graphical components have been developed to fulfill project-specific user requirements. For example video animations can be generated at runtime based on image data requests matching a specific search criteria. In addition, interoperability is achieved with other tools for data visualization purposes using internationally approved standards (c.f., IVOA SAMP), a messaging protocol already adopted by several analysis tools (ds9, Aladin, Gaia). In order to avoid the increasingly common network constraints affecting the end-user’s daily work the system has been designed to cope with possible restrictive firewall set up. Therefore, ESA New Generation archives are accessible from anyplace where standard basic port 80 HTTP connections are available.

  1. Optimal Spectrum Access for Users in Multi-Channel Cognitive Radio Networks

    Directory of Open Access Journals (Sweden)

    Vivek Agrawal

    2013-09-01

    Full Text Available Cognitive Radio, a software defined radio, is an emerging technology which uses opportunistic spectrum access (OSA for the efficient utilization of the spectrum. Its main aim is to utilize the unused portions of the spectrum by allowing unlicensed users (secondary users to transmit data in absence of primary users. In this paper the assignment of multiple primary and secondary users in a multiple channel system is addressed with the sole aim of optimizing the total throughput. We have considered an optimal spectrum access (OSA algorithm for the allotment of both the primary and secondary users in a multiple channel system and compared the results with the well-known meta-heuristic techniques such as Simulated Annealing (SA and Tabu Search (TS. The results reveal that OSA algorithm is more efficient as compared to SA and TS as far as throughput optimization is considered.

  2. Power Allocation and Pricing in Multi-User Relay Networks Using Stackelberg and Bargaining Games

    CERN Document Server

    Cao, Qian; Jing, Yindi

    2012-01-01

    This paper considers a multi-user single-relay wireless network, where the relay gets paid for helping the users forward signals, and the users pay to receive the relay service. We study the relay power allocation and pricing problems, and model the interaction between the users and the relay as a two-level Stackelberg game. In this game, the relay, modeled as the service provider and the leader of the game, sets the relay price to maximize its revenue; while the users are modeled as customers and the followers who buy power from the relay for higher transmission rates. We use a bargaining game to model the negotiation among users to achieve a fair allocation of the relay power. Based on the proposed fair relay power allocation rule, the optimal relay power price that maximizes the relay revenue is derived analytically. Simulation shows that the proposed power allocation scheme achieves higher network sum-rate and relay revenue than the even power allocation. Furthermore, compared with the sum-rate-optimal so...

  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. On the Achievability of Interference Alignment for Three-Cell Multi-User MIMO Cellular Networks

    CERN Document Server

    Ma, Yanjun; Chen, Rui; Liu, Qin

    2011-01-01

    An interference alignment (IA) based scheme is proposed by joint design of transmit precoding matrices and receive beamforming matrices for the three-cell Multi-User MIMO (MU-MIMO) cellular network with constant channel between each node, where each base station (BS) is equipped with $M$ antennas, each mobile station (MS) is equipped with $N$ antennas, and $M \\geq N$. We assume $K$ cell-edge users are served per cell simultaneously where $K>1$, and BS sends $d$ data streams to each of its users. It is shown that $\\frac{M}{2}$ degrees of freedom (DoF) is achievable per cell when $M=N$, $K=\\frac{M}{2d}$, and $M$ is divisible by 2d, and $Kd$ DoF is achievable per cell if $M =KN$ and $d \\leq \\lfloor \\frac{M}{3K-1} \\rfloor$ or if $(3K -1)d \\leq M < KN $ and $d \\leq 3(KN-M)$. Furthermore, when there have extra dimensions at BSs, a space-division hybrid (SDH) scheme is proposed for the three-cell MU-MIMO cellular network, where cell-edge users and cell-center users are served simultaneously. Cell-edge users work ...

  5. 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.

  6. 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...

  7. 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.

  8. Privacy disclosure in Chinese social networking sites:An investigation of Renren users

    Institute of Scientific and Technical Information of China (English)

    Chenju; ZHU; Qi; HUANG; Qinghua; ZHU

    2014-01-01

    Purpose:This study was conducted to investigate the current situation of privacy disclosure(in the Chinese social networking sites.Design/methodology/approach:Data analysis was based on profiles of 240 college students on Renren.com,a popular college-oriented social networking site in China.Users’ privacy disclosure behaviors were studied and gender difference was analyzed particularly.Correlation analysis was conducted to examine the relationships among evaluation indicators involving user name,image,page visibility,message board visibility,completeness of education information and provision of personal information.Findings:A large amount of personal information was disclosed via social networking sites in China.Greater percentage of male users than female users disclosed their personal information.Furthermore,significantly positive relationships were found among page visibility,message board visibility,completeness of education information and provision of personal information.Research limitations:Subjects were collected from only one social networking website.Meanwhile,our survey involves subjective judgments of user name reliability,category of profile images and completeness of information.Practical implications:This study will be of benefit for college administrators,teachers and librarians to design courses for college students on how to use social networking sites safely.Originality /value:This empirical study is one of the first studies to reveal the current situation of privacy disclosure in the Chinese social networking sites and will help the research community gain a deeper understanding of privacy disclosure in the Chinese social networking sites.

  9. Tweeting badges: user motivations for displaying achievement in publicly networked environments.

    Science.gov (United States)

    Kwon, K Hazel; Halavais, Alexander; Havener, Shannon

    2015-02-01

    Badge systems, a common mechanism for gamification on social media platforms, provide a way for users to present their knowledge or experience to others. This study aims to contribute to the understanding of why social media users publicize their achievements in the form of online badges. Five motivational factors for badge display in public networked environments are distinguished-self-efficacy, social incentives, networked support, passing time, and inattentive sharing-and it is suggested that different badge types are associated with different motivations. System developers are advised to consider these components in their designs, applying the elements most appropriate to the communities they serve. Comparing user motivations associated with badges shared across boundaries provides a better understanding of how online badges relate to the larger social media ecosystem.

  10. 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.

  11. 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.

  12. Empirical analysis of web-based user-object bipartite networks

    CERN Document Server

    Shang, Mingsheng; Zhang, Yi-Cheng; Zhou, Tao

    2009-01-01

    Understanding the structure and evolution of web-based user-object networks is a significant task since they play a crucial role in e-commerce nowadays. This Letter reports the empirical analysis on two large-scale web sites, audioscrobbler.com and del.icio.us, where users are connected with music groups and bookmarks, respectively. The degree distributions and degree-degree correlations for both users and objects are reported. We propose a new index, named collaborative clustering coefficient, to quantify the clustering behavior based on the collaborative selection. Accordingly, the clustering properties and clustering-degree correlations are investigated. We report some novel phenomena well characterizing the selection mechanism of web users and outline the relevance of these phenomena to the information recommendation problem.

  13. Decentralized Inter-User Interference Suppression in Body Sensor Networks with Non-cooperative Game

    CERN Document Server

    Wu, Guowei; Xia, Feng; Yao, Lin; Xu, Zichuan

    2010-01-01

    Body Sensor Networks (BSNs) provide continuous health monitoring and analysis of physiological parameters. A high degree of Quality-of-Service (QoS) for BSN is extremely required. Inter-user interference is introduced by the simultaneous communication of BSNs congregating in the same area. In this paper, a decentralized inter-user interference suppression algorithm for BSN, namely DISG, is proposed. Each BSN measures the SINR from other BSNs and then adaptively selects the suitable channel and transmission power. By utilizing non-cooperative game theory and no regret learning algorithm, DISG provides an adaptive inter-user interference suppression strategy. The correctness and effectiveness of DISG is theoretically proved, and the experimental results show that DISG can reduce the effect of inter-user interference effectively.

  14. 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.

  15. A User Cooperation Stimulating Strategy Based on Cooperative Game Theory in Cooperative Relay Networks

    Directory of Open Access Journals (Sweden)

    Ping Zhang

    2009-01-01

    Full Text Available This paper proposes a user cooperation stimulating strategy among rational users. The strategy is based on cooperative game theory and enacted in the context of cooperative relay networks. Using the pricing-based mechanism, the system is modeled initially with two nodes and a Base Station (BS. Within this framework, each node is treated as a rational decision maker. To this end, each node can decide whether to cooperate and how to cooperate. Cooperative game theory assists in providing an optimal system utility and provides fairness among users. Under different cooperative forwarding modes, certain questions are carefully investigated, including “what is each node's best reaction to maximize its utility?” and “what is the optimal reimbursement to encourage cooperation?” Simulation results show that the nodes benefit from the proposed cooperation stimulating strategy in terms of utility and thus justify the fairness between each user.

  16. Estimation for Traffic Arrival Rate and Service Rate of Primary Users in Cognitive Radio Networks

    Institute of Scientific and Technical Information of China (English)

    Xiaolong Yang; Xuezhi Tan∗

    2015-01-01

    In order to estimate the traffic arrival rate and service rate parameters of primary users in cognitive radio networks, a hidden Markov model estimation algorithm ( HMM⁃EA) is proposed, which can provide better estimation performance than the energy detection estimation algorithm ( ED⁃EA ) . Firstly, spectrum usage behaviors of primary users are described by establishing a preemptive priority queue model, by which a real state transition probability matrix is derived. Secondly, cooperative detection is utilized to detect the real state of primary users and emission matrix is derived by considering both detection and false alarm probability. Then, a hidden Markov model is built based on the previous two steps, and evaluated through the forward⁃backward algorithm. Finally, the simulations results verify that the HMM⁃EA algorithm outperforms the ED⁃EA in terms of convergence performance, and therefore the secondary user is able to access the unused channel with the least busy probability in real time.

  17. 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.

  18. 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.

  19. [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.

  20. 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.

  1. Characterization of User-Perceived Quality of Service (QOS in Mobile Devices Using Network Pairwise Comparisons

    Directory of Open Access Journals (Sweden)

    Carlos E. Otero

    2010-08-01

    Full Text Available This paper presents a user-centric and application-specific QoS assessment methodology for cellularcommunication networks. Specifically, it uses the Analytic Hierarchy Process (AHP to evaluate QoS as amulti-criteria decision problem that represents how well cellular networks’ data services are perceivedgiven particular sets of application classes and relative to other networks servicing in the same area. Aspart of the methodology, drive testing is performed to collect objective measurements associated withidentified QoS criteria for data services. Once drive testing is performed and data collected, multiplenetworks are compared to determine the network that provides higher QoS based on users’ perception ofquality. The selection of the best performing network is based on the output provided by the AHPapproach, which is used as unified measurement of the perceived QoS by users on different networks. Inorder to determine application-specific priorities, the approach presented uses three different applicationclasses, including Emergency, Business, and Personal. For each class, the relative importance of eachquality evaluation criteria is adjusted in the AHP procedure to reflect the priorities of the servicesexpected. Through several case studies, the approach is proven successful in providing a way foranalyzing user-centric QoS for application-specific scenarios.

  2. 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.

  3. 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.

  4. 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

    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...... and Danish national statistics. These Danish data are discussed together with international studies. Through the presentation of these different projects and examples, it is shown how user behaviour is at least as important as the efficiency of technology when explaining households' energy consumption...... 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...

  5. Users of assistive technology also require assistance with ergonomics.

    Science.gov (United States)

    Long, Jennifer

    2011-01-01

    This case study describes an ergonomics workstation assessment conducted for an administrative worker with vision impairment due to keratoconus. The worker, PT, was provided with multiple assistive technology devices to help her with her work, but this resulted in an overcrowded workspace. The purpose of the workstation assessment was to assist the worker with her workstation arrangement to make it more comfortable and efficient. During the assessment, a range of physical, cognitive and organisational ergonomics issues were identified and addressed. Multidisciplinary teams are often used in the rehabilitation of workers with complex medical problems. An ergonomist can play a valuable role on this team. © 2011 - IOS Press and the authors. All rights reserved

  6. 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 (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.

  7. Towards a temporal network analysis of interactive WiFi users

    CERN Document Server

    Zhang, Yan; Zhang, Yi-Qing; Li, Xiang; 10.1209/0295-5075/98/68002

    2012-01-01

    Complex networks are used to depict topological features of complex systems. The structure of a network characterizes the interactions among elements of the system, and facilitates the study of many dynamical processes taking place on it. In previous investigations, the topological infrastructure underlying dynamical systems is simplified as a static and invariable skeleton. However, this assumption cannot cover the temporal features of many time-evolution networks, whose components are evolving and mutating. In this letter, utilizing the log data of WiFi users in a Chinese university campus, we infuse the temporal dimension into the construction of dynamical human contact network. By quantitative comparison with the traditional aggregation approach, we find that the temporal contact network differs in many features, e.g., the reachability, the path length distribution. We conclude that the correlation between temporal path length and duration is not only determined by their definitions, but also influenced b...

  8. Generalized Distributed Network Coding Based on Nonbinary Linear Block Codes for Multi-User Cooperative Communications

    CERN Document Server

    Rebelatto, João Luiz; Li, Yonghui; Vucetic, Branka

    2010-01-01

    In this work, we propose and analyze a generalized construction of distributed network codes for a network consisting of M users sending different information to a common base station through independent block fading channels. The aim is to increase the diversity order of the system without reducing its code rate. The proposed scheme, called generalized dynamic network codes (GDNC), is a generalization of the dynamic network codes (DNC) recently proposed by Xiao and Skoglung. The design of the network codes that maximizes the diversity order is recognized as equivalent to the design of linear block codes over a nonbinary finite field under the Hamming metric. The proposed scheme offers a much better tradeoff between rate and diversity order. An outage probability analysis showing the improved performance is carried out, and computer simulations results are shown to agree with the analytical results.

  9. A Wireless Sensor Network for Hospital Security: From User Requirements to Pilot Deployment

    Directory of Open Access Journals (Sweden)

    Kaseva Ville

    2011-01-01

    Full Text Available Increasing amount of Wireless Sensor Network (WSN applications require low network delays. However, current research on WSNs has mainly concentrated on optimizing energy-efficiency omitting low network delays. This paper presents a novel WSN design targeted at applications requiring low data transfer delays and high reliability. We present the whole design flow from user requirements to an actual pilot deployment in a real hospital unit. The WSN includes multihop low-delay data transfer and energy-efficient mobile nodes reaching lifetime of years with small batteries. The nodes communicate using a low-cost low-power 2.4 GHz radio. The network is used in a security application with which personnel can send alarms in threatening situations. Also, a multitude of sensor measurements and actuator control is possible with the WSN. A full-scale pilot deployment is extensively experimented for performance results. Currently, the pilot network is in use at the hospital.

  10. 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 enab

  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. 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.

  13. 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.

  14. 移动网中的WLAN分流技术%WLAN Offload Technology in Mobile Network

    Institute of Scientific and Technical Information of China (English)

    许慕鸿

    2011-01-01

    The development of smart phone and mobile Internet brings great pressure to mobile network and WLAN access provided to the mobile user becomes the important method to offload the packet traffic from the mobile network.This paper introduces the basic WLAN offload technology firstly,and then describers the new technology for session continuity between WLAN network and mobile network.%智能终端和移动互联网的发展给移动网络带来了压力,为移动用户提供WLAN接入,成为移动网络数据业务分流的重要手段。本文在介绍WLAN分流基本技术的基础上,分析了用于解决WLAN和移动网络业务连续性问题的新技术。

  15. 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.

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

    Science.gov (United States)

    2015-05-22

    Shreyasi Das1, Niloy Ganguly1, and Saptarshi Ghosh2,3 1 Department of CSE, Indian Institute of Technology Kharagpur, Kharagpur, India koustav.rudra...and Technology Shibpur, Howrah, India Abstract. To help users find popular topics of discussion, Twitter peri- odically publishes ‘trending topics...considering that it is a complex nine-class classification task. 3 URLs leading to social media sites like Facebook, Twitter, Instagram, are ignored

  17. 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.

  18. The Analysis of User Behaviour of a Network Management Training Tool using a Neural Network

    Directory of Open Access Journals (Sweden)

    Helen Donelan

    2005-10-01

    Full Text Available A novel method for the analysis and interpretation of data that describes the interaction between trainee network managers and a network management training tool is presented. A simulation based approach is currently being used to train network managers, through the use of a simulated network. The motivation is to provide a tool for exposing trainees to a life like situation without disrupting a live network. The data logged by this system describes the detailed interaction between trainee network manager and simulated network. The work presented here provides an analysis of this interaction data that enables an assessment of the capabilities of the trainee network manager as well as an understanding of how the network management tasks are being approached. A neural network architecture is implemented in order to perform an exploratory data analysis of the interaction data. The neural network employs a novel form of continuous self-organisation to discover key features in the data and thus provide new insights into the learning and teaching strategies employed.

  19. Online Community and User-Generated Content: Understanding the Role of Social Networks

    Science.gov (United States)

    Oh, Jeong Ha

    2010-01-01

    Models of user generated content (UGC) creation such as Facebook, MySpace, and YouTube are facing robust growth accelerated by the adoption of Web 2.0 technologies and standards. These business models offer a fascinating avenue for exploring the role of social influence online. This dissertation is motivated by the success of YouTube, which is…

  20. Online Community and User-Generated Content: Understanding the Role of Social Networks

    Science.gov (United States)

    Oh, Jeong Ha

    2010-01-01

    Models of user generated content (UGC) creation such as Facebook, MySpace, and YouTube are facing robust growth accelerated by the adoption of Web 2.0 technologies and standards. These business models offer a fascinating avenue for exploring the role of social influence online. This dissertation is motivated by the success of YouTube, which is…

  1. 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

  2. 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.

  3. 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.

  4. 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.

  5. Optical coherent technologies in next generation access networks

    Science.gov (United States)

    Iwatsuki, Katsumi; Tsukamoto, Katsutoshi

    2012-01-01

    This paper reviews optical coherent technologies in next generation access networks with the use of radio over fiber (RoF), which offer key enabling technologies of wired and wireless integrated and/or converged broadband access networks to accommodate rapidly widespread cloud computing services. We describe technical issues on conventional RoF based on subcarrier modulation (SCM) and their countermeasures. Two examples of RoF access networks with optical coherent technologies to solve the technical issues are introduced; a video distribution system with FM conversion and wired and wireless integrated wide-area access network with photonic up- and down-conversion.

  6. 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.

  7. Computer Network Security Technology%浅谈计算机网络安全技术

    Institute of Scientific and Technical Information of China (English)

    梁其烺

    2011-01-01

    从当前计算机网络安全现状入手,对主要的网络安全威胁进行了讨论。最后分析了计算机网络安全技术的类型,力图使网络设计者和使用者对网络安全有一个全面的认识,从而能正确采用成功对策。%The present situation of the current computer network security,network security of the main threats were discussed,the final analysis,the type of computer network security technology to try to make the network designers and users of network security with a comprehensive understanding, so that it can correctly the use of successful strategies.

  8. 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.

  9. Functional connectivity alterations in brain networks relevant to self-awareness in chronic cannabis users.

    Science.gov (United States)

    Pujol, Jesus; Blanco-Hinojo, Laura; Batalla, Albert; López-Solà, Marina; Harrison, Ben J; Soriano-Mas, Carles; Crippa, Jose A; Fagundo, Ana B; Deus, Joan; de la Torre, Rafael; Nogué, Santiago; Farré, Magí; Torrens, Marta; Martín-Santos, Rocío

    2014-04-01

    Recreational drugs are generally used to intentionally alter conscious experience. Long-lasting cannabis users frequently seek this effect as a means to relieve negative affect states. As with conventional anxiolytic drugs, however, changes in subjective feelings may be associated with memory impairment. We have tested whether the use of cannabis, as a psychoactive compound, is associated with alterations in spontaneous activity in brain networks relevant to self-awareness, and whether such potential changes are related to perceived anxiety and memory performance. Functional connectivity was assessed in the Default and Insula networks during resting state using fMRI in 28 heavy cannabis users and 29 control subjects. Imaging assessments were conducted during cannabis use in the unintoxicated state and repeated after one month of controlled abstinence. Cannabis users showed increased functional connectivity in the core of the Default and Insula networks and selective enhancement of functional anticorrelation between both. Reduced functional connectivity was observed in areas overlapping with other brain networks. Observed alterations were associated with behavioral measurements in a direction suggesting anxiety score reduction and interference with memory performance. Alterations were also related to the amount of cannabis used and partially persisted after one month of abstinence. Chronic cannabis use was associated with significant effects on the tuning and coupling of brain networks relevant to self-awareness, which in turn are integrated into brain systems supporting the storage of personal experience and motivated behavior. The results suggest potential mechanisms for recreational drugs to interfere with higher-order network interactions generating conscious experience. Copyright © 2014 Elsevier Ltd. All rights reserved.

  10. The use of modern technology in education: A user study on the digitization of cultural heritage

    Directory of Open Access Journals (Sweden)

    MILICA LAJBENŠPERGER

    2013-09-01

    Full Text Available In the Republic of Serbia the idea that the digitization of cultural heritage could be used to popularize and utilize modern technologies in education was first realized in 2012. One of the results of this project was a user study. In this paper we indicate some of project’s fragments and present some of the results of the conducted research.

  11. 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…

  12. 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

  13. 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…

  14. USER-CENTRIC PERSONALIZED MULTIFACET MODEL TRUST IN ONLINE SOCIAL NETWORK

    Directory of Open Access Journals (Sweden)

    Liu Ban Chieng

    2014-12-01

    Full Text Available Online Social Network (OSN has become the most popular platform on the Internet that can provide an interesting and creative ways to communicate, sharing and meets with peoples. As OSNs mature, issues regarding proper use of OSNs are also growing. In this research, the challenges of online social networks have been investigated. The current issues in some of the Social Network Sites are being studied and compared. Cyber criminals, malware attacks, physical threat, security and usability and some privacy issues have been recognized as the challenges of the current social networking sites. Trust concerns have been raised and the trustworthiness of social networking sites has been questioned. Currently, the trust in social networks is using the single- faceted approach, which is not well personalized, and doesn’t account for the subjective views of trust, according to each user, but only the general trust believes of a group of population. The trust level towards a person cannot be calculated and trust is lack of personalization. From our initial survey, we had found that most people can share their information without any doubts on OSN but they normally do not trust all their friends equally and think there is a need of trust management. We had found mixed opinions in relation to the proposed rating feature in OSNs too. By adopting the idea of multi-faceted trust model, a user-centric model that can personalize the comments/photos in social network with user’s customized traits of trust is proposed. This model can probably solve many of the trust issues towards the social networking sites with personalized trust features, in order to keep the postings on social sites confidential and integrity.

  15. Enhanced Password Based Security System Based on User Behavior using Neural Networks

    Directory of Open Access Journals (Sweden)

    Gour Sundar Mitra Thakur

    2012-04-01

    Full Text Available There are multiple numbers of security systems are available to protect your computer/resources. Among them, password based systems are the most commonly used system due to its simplicity, applicability and cost effectiveness But these types of systems have higher sensitivity to cyber-attack. Most of the advanced methods for authentication based on password security encrypt the contents of password before storing or transmitting in the physical domain. But all conventional encryption methods are having its own limitations, generally either in terms of complexity or in terms of efficiency.In this paper an enhanced password based security system has been proposed based on user typing behavior, which will attempt to identify authenticity of any user failing to login in first few attempts by analyzing the basic user behaviors/activities and finally training them through neural network and classifying them as genuine or intruder

  16. U-Net/SLE: A Java-Based User-Customizable Virtual Network Interface

    Directory of Open Access Journals (Sweden)

    Matt Welsh

    1999-01-01

    Full Text Available We describe U‐Net/SLE (Safe Language Extensions, a user‐level network interface architecture which enables per‐application customization of communication semantics through downloading of user extension applets, implemented as Java classfiles, to the network interface. This architecture permits applications to safely specify code to be executed within the NI on message transmission and reception. By leveraging the existing U‐Net model, applications may implement protocol code at the user level, within the NI, or using some combination of the two. Our current implementation, using the Myricom Myrinet interface and a small Java Virtual Machine subset, allows host communication overhead to be reduced and improves the overlap of communication and computation during protocol processing.

  17. Proof-of-Concept System for Opportunistic Spectrum Access in Multi-user Decentralized Networks

    Directory of Open Access Journals (Sweden)

    Sumit J. Darak

    2016-09-01

    Full Text Available Poor utilization of an electromagnetic spectrum and ever increasing demand for spectrum have led to surge of interests in opportunistic spectrum access (OSA based paradigms like cognitive radio and unlicensed LTE. In OSA for decentralized networks, frequency band selection from wideband spectrum is a challenging task since secondary users (SUs do not share any information with each other. In this paper, a new decision making policy (DMP has been proposed for OSA in the multi-user decentralized networks. First contribution is an accurate characterization of frequency bands using Bayes-UCB algorithm. Then, a novel SU orthogonization scheme using Bayes-UCB algorithm is proposed replacing randomization based scheme. At the end, USRP testbed has been developed for analyzing the performance of DMPs using real radio signals. Experimental results show that the proposed DMP offers significant improvement in spectrum utilization, fewer subband switching and collisions compared to other DMPs.

  18. 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.

  19. 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

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

    Science.gov (United States)

    2016-05-02

    National Defense Motivation With its rapid growth, social media has gained the interst of national defense policy makers and strategists. In January of... Motivation Social networks have rapidly risen in size over the past decade and today represent one of the main platforms through which social interactions...occur. Current estimates are that 74% of adult Internet users are on social media and in many other parts of the world, including emerging markets, this

  1. User behavior and technology development. Shaping sustainable relations between consumers and technologies

    NARCIS (Netherlands)

    Slob, A.F.L.; Verbeek, P.P.

    2006-01-01

    Environmental policy has long been determined by a dichotomy between technology and behavior. Some approaches stress the importance of technology and technological innovation, while others focus on behavioral change. Each approach has its limitations, however, since technology and behavior often app

  2. Trinity:Walking on a User-Ob ject-Tag Heterogeneous Network for Personalised Recommendations

    Institute of Scientific and Technical Information of China (English)

    Ming-Xin Gan; Lily Sun; Rui Jiang

    2016-01-01

    The rapid evolution of the Internet has been appealing for effective recommender systems to pinpoint useful information from online resources. Although historical rating data has been widely used as the most important information in recommendation methods, recent advancements have been demonstrating the improvement in recommendation performance with the incorporation of tag information. Furthermore, the availability of tag annotations has been well addressed by such fruitful online social tagging applications as CiteULike, MovieLens and BibSonomy, which allow users to express their preferences, upload resources and assign their own tags. Nevertheless, most existing tag-aware recommendation approaches model relationships among users, objects and tags using a tripartite graph, and hence overlook relationships within the same types of nodes. To overcome this limitation, we propose a novel approach, Trinity, to integrate historical data and tag information towards personalised recommendation. Trinity constructs a three-layered object-user-tag network that considers not only interconnections between different types of nodes but also relationships within the same types of nodes. Based on this heterogeneous network, Trinity adopts a random walk with restart model to assign the strength of associations to candidate objects, thereby providing a means of prioritizing the objects for a query user. We validate our approach via a series of large-scale 10-fold cross-validation experiments and evaluate its performance using three comprehensive criteria. Results show that our method outperforms several existing methods, including supervised random walk with restart, simulation of resource allocating processes, and traditional collaborative filtering.

  3. 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.

  4. 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.

  5. Measurement and Analysis of Quality of Service of Mobile Networks in Afghanistan – End User Perspective

    Directory of Open Access Journals (Sweden)

    M. A.

    2016-12-01

    Full Text Available Enhanced Quality of Service (QoS and satisfaction of mobile phone user are major concerns of a service provider. In order to manage network efficiently and to provide enhanced end – to – end Quality of Experience (QoE, operator is expected to measure and analyze QoS from various perspectives and at different relevant points of network. The scope of this paper is measurement and statistically analysis of QoS of mobile networks from end user perspective in Afghanistan. The study is based on primary data collected on random basis from 1,515 mobile phone users of five cellular operators. The paper furthermore proposes adequate technical solutions to mobile operators in order to address existing challenges in the area of QoS and to remain competitive in the market. Based on the result of processed data, considering geographical locations, population and telecom regulations of the government, authors recommend deployment of small cells (SCs, increasing number of regular performance tests, optimal placement of base stations, increasing number of carriers, and high order sectorization as proposed technical solutions.

  6. From technological acceptability to appropriation by users: methodological steps for device assessment in road safety.

    Science.gov (United States)

    Bordel, Stéphanie; Somat, Alain; Barbeau, Hervé; Anceaux, Françoise; Greffeuille, Catherine; Menguy, Gaëlle; Pacaux, Marie-Pierre; Subirats, Peggy; Terrade, Florence; Gallenne, Marie-Line

    2014-06-01

    This article presents the methodology developed within the framework of the research project SARI (Automated Road Surveillance for Driver and Administrator Information). This methodology is based on the logic of action research. The article presents the different stages in the development of technological innovation addressing vehicle control loss when driving on a curve. The results observed in speed reduction illustrate that no matter how optimal an innovation may be technologically speaking, it is only as effective as it is acceptable from a user standpoint. This acceptability can only be obtained if the technology is developed by engineers in liaison with social science specialists.

  7. Network Science Collaborative Technology Alliance: Overview

    Science.gov (United States)

    2010-02-01

    mysterious lives: evolve, change, and behave in little- understood ways • Network science studies fundamental laws of evolution and behaviors of “living...relations of three dissimilar (and most influential) genres of networks: social, information, communications • The most powerful and Army-relevant...centers to balance (a) in-depth expertise in each network genre and (b) relations, dependencies and mutual influences of three genres . Network Science

  8. Bridge Management Strategy Based on Extreme User Costs for Bridge Network Condition

    Directory of Open Access Journals (Sweden)

    Ladislaus Lwambuka

    2014-01-01

    Full Text Available This paper presents a practical approach for prioritization of bridge maintenance within a given bridge network. The maintenance prioritization is formulated as a multiobjective optimization problem where the simultaneous satisfaction of several conflicting objectives includes minimization of maintenance costs, maximization of bridge deck condition, and minimization of traffic disruption and associated user costs. The prevalence of user cost during maintenance period is twofold; the first case refers to the period of dry season where normally the traffic flow is diverted to alternative routes usually resurfaced to regain traffic access. The second prevalence refers to the absence of alternative routes which is often the case in the least developed countries; in this case the user cost referred to results from the waiting time while the traffic flow is put on hold awaiting accomplishment of the maintenance activity. This paper deals with the second scenario of traffic closure in the absence of alternative diversion routes which in essence results in extreme user cost. The paper shows that the multiobjective optimization approach remains valid for extreme cases of user costs in the absence of detour roads as often is the scenario in countries with extreme poor road infrastructure.

  9. 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…

  10. 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.

  11. User-centred and context-aware identity management in mobile ad-hoc networks

    CERN Document Server

    Arabo, Abdullahi

    2013-01-01

    The emergent notion of ubiquitous computing makes it possible for mobile devices to communicate and provide services via networks connected in an ad-hoc manner. These have resulted in the proliferation of wireless technologies such as Mobile Ad-hoc Networks (MANets), which offer attractive solutions for services that need flexible setup as well as dynamic and low cost wireless connectivity. However, the growing trend outlined above also raises serious concerns over Identity Management (IM) du...

  12. Protect You More Than Blank:Anti-Learning Sensitive User Information in the Social Networks

    Institute of Scientific and Technical Information of China (English)

    袁明轩; 陈雷; 梅宏

    2014-01-01

    Social networks are getting more and more attention in recent years. People join social networks to share their information with others. However, due to the different cultures and backgrounds, people have different requirements on what kind of information should be published. Currently, when social network websites publish data, they just leave the information that a user feels sensitive blank. This is not enough due to the existence of the label-structure relationship. A group of analyzing algorithms can be used to learn the blank information with high accuracy. In this paper, we propose a personalized model to protect private information in social networks. Specifically, we break the label-structure association by slightly changing the edges in some users’ neighborhoods. More importantly, in order to increase the usability of the published graph, we also preserve the influence value of each user during the privacy protection. We verify the effectiveness of our methods through extensive experiments. The results show that the proposed methods can protect sensitive labels against learning algorithms and at the same time, preserve certain graph utilities.

  13. How is technology accepted by users? A review of technology acceptance models and theories

    OpenAIRE

    Alomary, Azza; Woollard, John

    2015-01-01

    This paper provides a literature review of the popular theories and models of technology acceptance of relevance to today’s technology developments in the 4E context. The original technology acceptance model (TAM) was derived from the theory of reasoned action and has since been developed and extended to include factors of age, gender, prior experience, ability, etc. It provides the framework to measure users’ perceptions of and intentions to use technology within and across organisations. Th...

  14. A Technology Assessment of Personal Computers. Vol. II: Personal Computer Technology, Users, and Uses.

    Science.gov (United States)

    Nilles, Jack M.

    This volume reports on the initial phase of a technology assessment of personal computers. First, technological developments that will influence the rate of diffusion of personal computer technology among the general populace are examined. Then the probable market for personal computers is estimated and analyzed on a functional basis, segregating…

  15. 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.

  16. Successful implementation of new technologies in nursing care: a questionnaire survey of nurse-users

    Directory of Open Access Journals (Sweden)

    Bekkema Nienke

    2011-10-01

    Full Text Available Abstract Background A growing number of new technologies are becoming available within nursing care that can improve the quality of care, reduce costs, or enhance working conditions. However, such effects can only be achieved if technologies are used as intended. The aim of this study is to gain a better understanding of determinants influencing the success of the introduction of new technologies as perceived by nursing staff. Methods The study population is a nationally representative research sample of nursing staff (further referred to as the Nursing Staff Panel, of whom 685 (67% completed a survey questionnaire about their experiences with recently introduced technologies. Participants were working in Dutch hospitals, psychiatric organizations, care organizations for mentally disabled people, home care organizations, nursing homes or homes for the elderly. Results Half of the respondents were confronted with the introduction of a new technology in the last three years. Only half of these rated the introduction of the technology as positive. The factors most frequently mentioned as impeding actual use were related to the (kind of technology itself, such as malfunctioning, ease of use, relevance for patients, and risks to patients. Furthermore nursing staff stress the importance of an adequate innovation strategy. Conclusions A prerequisite for the successful introduction of new technologies is to analyse determinants that may impede or enhance the introduction among potential users. For technological innovations special attention has to be paid to the (perceived characteristics of the technology itself.

  17. Successful implementation of new technologies in nursing care: a questionnaire survey of nurse-users.

    Science.gov (United States)

    de Veer, Anke J E; Fleuren, Margot A H; Bekkema, Nienke; Francke, Anneke L

    2011-10-27

    A growing number of new technologies are becoming available within nursing care that can improve the quality of care, reduce costs, or enhance working conditions. However, such effects can only be achieved if technologies are used as intended. The aim of this study is to gain a better understanding of determinants influencing the success of the introduction of new technologies as perceived by nursing staff. The study population is a nationally representative research sample of nursing staff (further referred to as the Nursing Staff Panel), of whom 685 (67%) completed a survey questionnaire about their experiences with recently introduced technologies. Participants were working in Dutch hospitals, psychiatric organizations, care organizations for mentally disabled people, home care organizations, nursing homes or homes for the elderly. Half of the respondents were confronted with the introduction of a new technology in the last three years. Only half of these rated the introduction of the technology as positive.The factors most frequently mentioned as impeding actual use were related to the (kind of) technology itself, such as malfunctioning, ease of use, relevance for patients, and risks to patients. Furthermore nursing staff stress the importance of an adequate innovation strategy. A prerequisite for the successful introduction of new technologies is to analyse determinants that may impede or enhance the introduction among potential users. For technological innovations special attention has to be paid to the (perceived) characteristics of the technology itself.

  18. 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.

  19. 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...

  20. A Topic Space Oriented User Group Discovering Scheme in Social Network: A Trust Chain Based Interest Measuring Perspective

    Directory of Open Access Journals (Sweden)

    Wang Dong

    2016-01-01

    Full Text Available Currently, user group has become an effective platform for information sharing and communicating among users in social network sites. In present work, we propose a single topic user group discovering scheme, which includes three phases: topic impact evaluation, interest degree measurement, and trust chain based discovering, to enable selecting influential topic and discovering users into a topic oriented group. Our main works include (1 an overview of proposed scheme and its related definitions; (2 topic space construction method based on topic relatedness clustering and its impact (influence degree and popularity degree evaluation; (3 a trust chain model to take user relation network topological information into account with a strength classification perspective; (4 an interest degree (user explicit and implicit interest degree evaluation method based on trust chain among users; and (5 a topic space oriented user group discovering method to group core users according to their explicit interest degrees and to predict ordinary users under implicit interest and user trust chain. Finally, experimental results are given to explain effectiveness and feasibility of our scheme.

  1. An Architecture for Coexistence with Multiple Users in Frequency Hopping Cognitive Radio Networks

    Science.gov (United States)

    2013-03-01

    Technology AFRL Air Force Research Laboratory AHS Adaptive Hopset Selector BEE2 Berkeley Emulation Engine 2 BRAM Block RAM CE Cognitive Engine CR...REM merger, key loader, two 64x32 register files for storing the aggregate REM and the key, the hopset selector, and a BRAM section in which open...components built into the board. We used a generic VHDL block RAM ( BRAM ) structure given in the XST User Guide for storing available channels [41]. 75 4

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

    Directory of Open Access Journals (Sweden)

    Yaghoobi

    2016-07-01

    Full Text Available 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-monitoring and cybercrime scales were sent to 500 social network users. Of these, 203 users (103 men and 100 women filled out the questionnaires. Results 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. Conclusions Attachment styles have significant relationships with both self-monitoring and cybercrime. Self-monitoring and attachment styles are significant predictors of cybercrimes.

  4. 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.

  5. A Comparison of Users' Personal Information Sharing Awareness, Habits, and Practices in Social Networking Sites and E-Learning Systems

    Science.gov (United States)

    Ball, Albert L.

    2012-01-01

    Although reports of identity theft continue to be widely published, users continue to post an increasing amount of personal information online, especially within social networking sites (SNS) and e-learning systems (ELS). Research has suggested that many users lack awareness of the threats that risky online personal information sharing poses to…

  6. Specialist physicians' knowledge and beliefs about telemedicine: a comparison of users and nonusers of the technology.

    Science.gov (United States)

    Barton, Phoebe Lindsey; Brega, Angela G; Devore, Patricia A; Mueller, Keith; Paulich, Marsha J; Floersch, Natasha R; Goodrich, Glenn K; Talkington, Sylvia G; Bontrager, Jeff; Grigsby, Bill; Hrincevich, Carol; Neal, Susannah; Loker, Jeff L; Araya, Tesfa M; Bennett, Rachael E; Krohn, Neil; Grigsby, Jim

    2007-10-01

    Telemedicine as a technology has been available for nearly 50 years, but its diffusion has been slower than many had anticipated. Even efforts to reimburse providers for interactive video (IAV) telemedicine services have had a limited effect on rates of participation. The resulting low volume of services provided (and consequent paucity of research subjects) makes the phenomenon difficult to study. This paper, part of a larger study that also explores telemedicine utilization from the perspectives of referring primary care physicians and telemedicine system administrators, reports the results of a survey of specialist and subspecialist physicians who are users and nonusers of telemedicine. The survey examined self-assessed knowledge and beliefs about telemedicine among users and nonusers, examining also the demographic characteristics of both groups. Statistically significant differences were found in attitudes toward telemedicine between users and nonusers, but in many respects the views of the two groups were rather similar. Physicians who used telemedicine were aware of the limitations of the technology, but also recognized its potential as a means of providing consultation. Demographic differences did not explain the differences in the knowledge and beliefs of user and nonuser consultant physicians, although some of the differences may be explained by other aspects of the professional environment.

  7. The impact of information technology and networks: new perspectives for scientific, technical and medical (STM) publishing

    Science.gov (United States)

    De Kemp, Arnoud

    This contribution is a strongly abbreviated notation of a much longer presentation at the Workshop on Strategies and Techniques of Information for Astronomy, organized by the European Science Foundation in Strasbourg on 21/22 June 1996. The process of publishing will undergo dramatic changes due to the influences of information technology and networks. The publishing business as a whole will shift from traditional print- and paper-based organisations to a fully digital workflow from author to end-user. Electronic publishing has moved from pre-print activities to digital preprints on a variety of servers, but still most scientific documentation is printed and not only for archival purposes. In this short contribution, a plea is made for new rules in scientific communication that authors, editors, publishers, societies, libraries and users can recognize. In addition, in the electronic age we need more security for copyright, transactions over networks and against misuse in general.

  8. 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

    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...... 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....

  9. Enhancing a taxonomy for health information technology: an exploratory study of user input towards folksonomy.

    Science.gov (United States)

    Dixon, Brian E; McGowan, Julie J

    2010-01-01

    The U.S. Agency for Healthcare Research and Quality has created a public website to disseminate critical information regarding its health information technology initiative. The website is maintained by AHRQ's Natiomal Resource Center (NRC) for Health Information Technology. In the latest continuous quality improvement project, the NRC used the site's search logs to extract user-generated search phrases. The phrases were then compared to the site's controlled vocabulary with respect to language, grammar, and search precision. Results of the comparison demonstrate that search log data can be a cost-effective way to improve controlled vocabularies as well as information retrieval. User-entered search phrases were found to also share many similarities with folksonomy tags.

  10. A phone-assistive device based on Bluetooth technology for cochlear implant users.

    Science.gov (United States)

    Qian, Haifeng; Loizou, Philipos C; Dorman, Michael F

    2003-09-01

    Hearing-impaired people, and particularly hearing-aid and cochlear-implant users, often have difficulty communicating over the telephone. The intelligibility of telephone speech is considerably lower than the intelligibility of face-to-face speech. This is partly because of lack of visual cues, limited telephone bandwidth, and background noise. In addition, cellphones may cause interference with the hearing aid or cochlear implant. To address these problems that hearing-impaired people experience with telephones, this paper proposes a wireless phone adapter that can be used to route the audio signal directly to the hearing aid or cochlear implant processor. This adapter is based on Bluetooth technology. The favorable features of this new wireless technology make the adapter superior to traditional assistive listening devices. A hardware prototype was built and software programs were written to implement the headset profile in the Bluetooth specification. Three cochlear implant users were tested with the proposed phone-adapter and reported good speech quality.

  11. Improving network service performance and reliability via links trunking technologies

    Institute of Scientific and Technical Information of China (English)

    GUO Hui; WANG Yun-peng; WANG Zhi-guang; ZHOU Jing-li

    2006-01-01

    With the increase ofhigh-speed network backbones, the performance of server's network interface gradually becomes a pivotal factor. This study provides a method called Ethernet Links Trunking (ELT) technology for achieving efficient connectivity between backbones and servers, which provides higher bandwidth and availability of server network interface. The overview of the ELT technology and the results of performance experiment are presented in this paper. Findings showed that the network bandwidth can be scaled by multiple ELT technologies so that more reliable network connectivity can be guaranteed. Some crucial techniques such as Adapter Load Balancing (ALB) and Adapter Fault Tolerance (AFT) are presented in this paper. Experimental results showed that parallel channels of Fast Ethernet are both necessary and sufficient for supporting the data rates of multiple concurrent file transfers on file server.

  12. 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.

  13. 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.

  14. 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.

  15. 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.

  16. 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.

  17. Artificial Neural Networks and Instructional Technology.

    Science.gov (United States)

    Carlson, Patricia A.

    1991-01-01

    Artificial neural networks (ANN), part of artificial intelligence, are discussed. Such networks are fed sample cases (training sets), learn how to recognize patterns in the sample data, and use this experience in handling new cases. Two cognitive roles for ANNs (intelligent filters and spreading, associative memories) are examined. Prototypes…

  18. Artificial Neural Networks and Instructional Technology.

    Science.gov (United States)

    Carlson, Patricia A.

    1991-01-01

    Artificial neural networks (ANN), part of artificial intelligence, are discussed. Such networks are fed sample cases (training sets), learn how to recognize patterns in the sample data, and use this experience in handling new cases. Two cognitive roles for ANNs (intelligent filters and spreading, associative memories) are examined. Prototypes…

  19. 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.

  20. Secrecy outage analysis of multi-user multi-eavesdropper cellular networks in the face of cochannel interference

    Directory of Open Access Journals (Sweden)

    Yuan Jiang

    2015-02-01

    Full Text Available This paper studies the physical-layer security of a multi-user multi-eavesdropper cellular network, which is composed of multiple users communicating with a base station while the eavesdroppers may intercept the communications from users to the base station (BS. The cellular network is a time-slotted system with simultaneously transmission, in each time slot, a single user is scheduled to transmit messages to BS while the remaining users opportunistically receive information. Considering multiple users available in the cellular network, we present three multi-user scheduling schemes, namely the round-robin scheduling scheme as well as the suboptimal and optimal user scheduling schemes to improve the security of communication (from users to BS against eavesdropping attacks. We only need to assume that the channel state information (CSI of the main link spanning from users to BS is known in the suboptimal scheduling. On the contrary, the optimal scheduling is designed by assuming that the CSI of the main link and wiretap link (spanning from users to the eavesdropper are available. We further carry out secrecy diversity analysis and show that the round-robin always achieves only one diversity order, whereas the suboptimal and optimal user scheduling schemes achieve the full diversity. In addition, numerical results illustrate that the optimal scheduling performs the best and the round-robin has the worst performance in terms of the secrecy outage probability. Last, as the number of users increases, the secrecy outage probabilities of the suboptimal and optimal scheduling schemes decrease significantly.

  1. Analysis of User Behaviors and Evolution in Telecom Social Network%电信社群网络用户行为特征及演化分析

    Institute of Scientific and Technical Information of China (English)

    彭建平; 张业军

    2012-01-01

    通过某地移动客户的通话数据构建电信社群网络,并对其网络结构进行分析,发现电信社群网络并不满足小世界特征,而且该网络的演化是以边生长为主导.基于该结构特征,构建电信社群网的演化模型,发现网络非均匀性与节点的朋友圈数目、连接概率和新增节点边数有关.其研究结论对新运营商通过营销策略的制定,推动电信社群网络快速向小世界网络演化具有积极的现实意义.%The restructuring of China 's telecommunication industry has intensified the competition among telecommunication enterprises. To gain competitive edge, telecommunication enterprises need to adopt new technology to recruit potential users and maintain good customer relationships. The current literature on customer behaviors in the telecommunication industry mainly rely on the cluster analysis of basic properties of user data, without taking into account the interaction between users and network characteristics. Based on the complex network theory, this paper regards telephone number as the nodes and regards contact numbers as the interactive edge to build a telecommunication social network. We apply the research method in the existing literature to test the overall characteristics of this telecommunication social network. Based on the network characteristics, we propose an evolving model and derive major influential factors for a telecommunication social network. In addition, we investigate the trend of change of the telecommunication social network under different influencing factors. Our results can provide theoretical support for establishing fast and stable telecommunication social networks for mobile phone operators. We explore the evolving mechanism of this particular social network, and provide the following findings: (1) We collect and analyze four-month user communication data in the area. We use software to construct a telecommunication social network. We analyze the

  2. 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....

  3. 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.

  4. Assessing user engagement in a health promotion website using social networking.

    Science.gov (United States)

    Tague, Rhys; Maeder, Anthony J; Vandelanotte, Corneel; Kolt, Gregory S; Caperchione, Cristina M; Rosenkranz, Richard R; Savage, Trevor N; Van Itallie, Anetta

    2014-01-01

    Remote provision of supportive mechanisms for preventive health is a fast-growing area in eHealth. Web-based interventions have been suggested as an effective way to increase adoption and maintenance of healthy lifestyle behaviours. This paper describes results obtained in the "Walk 2.0" trial to promote physical activity through a self-managed walking programme, using a social networking website that provided an online collaborative environment. Engagement of participants with the website was assessed by monitoring usage of the individual social networking functions (e.g. status post). The results demonstrate that users generally preferred contributing non-interactive public posts of information concerned with their individual physical activity levels, and more occasionally communicating privately to friends. Further analysis of topics within posts was done by classifying word usage frequencies. Results indicated that the dominant topics are well aligned with the social environment within which physical activity takes place. Topics centred around four main areas: description of the activity, timing of the activity, affective response to the activity, and context within which the activity occurs. These findings suggest that strong levels of user awareness and communication occur in the social networking setting, indicative of beneficial self-image and self-actualisation effects.

  5. Information Cascades in Feed-based Networks of Users with Limited Attention

    CERN Document Server

    Sreenivasan, Sameet; Swami, Ananthram; Korniss, Gyorgy; Szymanski, Boleslaw

    2015-01-01

    We build a model of information cascades on feed-based networks, taking into account the finite attention span of users, message generation rates and message forwarding rates. Using this model, we study through simulations, the effect of the extent of user attention on the probability that the cascade becomes viral. In analogy with a branching process, we estimate the branching factor associated with the cascade process for different attention spans and different forwarding probabilities, and demonstrate that beyond a certain attention span, critical forwarding probabilities exist that constitute a threshold after which cascades can become viral. The critical forwarding probabilities have an inverse relationship with the attention span. Next, we develop a semi-analytical approach for our model, that allows us determine the branching factor for given values of message generation rates, message forwarding rates and attention spans. The branching factors obtained using this analytical approach show good agreemen...

  6. 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.

  7. 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.

  8. 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

  9. 社会网络服务及其用户行为分析%Social Network Services and Its User Behavior Analysis

    Institute of Scientific and Technical Information of China (English)

    毛承洁; 张龙; 庞川; 陈洁敏

    2013-01-01

    分析了社会网络服务的理论基础和实现技术,讨论了用户行为分析的研究方法.以面向学者的社会网络为例,分别应用第三方网络分析软件CNZZ和自主开发分析软件SCHOLAT后台管理软件进行了用户行为分析实例研究.%Social network is one of the hot topics of the current IT study and application. The emergence and development of social networks are described and the theoretical basis and technology of social network services are analyzed. The research methods of user behavior analysis in social networks are also discussed. In the case of scholar - oriented social network, the user behavior analysis is studied using the third - party network analysis software CNZZ and the self - developed analysis software for SCHOLAT Management.

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

    Energy Technology Data Exchange (ETDEWEB)

    Gram-Hanssen, K. [Danish Building Research Institute, Aalborg University, A.C. Meyers Vaenge 15, 2450 Copenhagen (Denmark)

    2013-08-15

    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, 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 and Danish national statistics. These Danish data are discussed together with international studies. Through the presentation of these different projects and examples, it is shown how user behaviour is at least as important as the efficiency of technology when explaining households' energy consumption 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 in future policy if energy demand is actually to be reduced. Furthermore, it is also argued that not only individual behaviour is relevant, but also a broader perspective on collectively shared low-carbon practices has to be promoted.

  11. 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...

  12. 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.

  13. Modified stochastic user-equilibrium assignment algorithm for urban rail transit under network operation

    Institute of Scientific and Technical Information of China (English)

    朱炜; 胡昊; 徐瑞华; 洪玲

    2013-01-01

    Based on the framework of method of successive averages(MSA), a modified stochastic user-equilibrium assignment algorithm was proposed, which can be used to calculate the passenger flow distribution of urban rail transit(URT) under network operation. In order to describe the congestion’s impact to passengers’ route choices, a generalized cost function with in-vehicle congestion was set up. Building on the k-th shortest path algorithm, a method for generating choice set with time constraint was embedded, considering the characteristics of network operation. A simple but efficient route choice model, which was derived from travel surveys for URT passengers in China, was introduced to perform the stochastic network loading at each iteration in the algorithm. Initial tests on the URT network in Shanghai City show that the methodology, with rational calculation time, promises to compute more precisely the passenger flow distribution of URT under network operation, compared with those practical algorithms used in today’s China.

  14. Using the NIATx Model to Implement User-Centered Design of Technology for Older Adults.

    Science.gov (United States)

    Gustafson, David H; Maus, Adam; Judkins, Julianne; Dinauer, Susan; Isham, Andrew; Johnson, Roberta; Landucci, Gina; Atwood, Amy K

    2016-01-14

    What models can effectively guide the creation of eHealth and mHealth technologies? This paper describes the use of the NIATx model as a framework for the user-centered design of a new technology for older adults. The NIATx model is a simple framework of process improvement based on the following principles derived from an analysis of decades of research from various industries about why some projects fail and others succeed: (1) Understand and involve the customer; (2) fix key problems; (3) pick an influential change leader; (4) get ideas from outside the field; (5) use rapid-cycle testing. This paper describes the use of these principles in technology development, the strengths and challenges of using this approach in this context, and lessons learned from the process. Overall, the NIATx model enabled us to produce a user-focused technology that the anecdotal evidence available so far suggests is engaging and useful to older adults. The first and fourth principles were especially important in developing the technology; the fourth proved the most challenging to use.

  15. A review of user-centered design for diabetes-related consumer health informatics technologies.

    Science.gov (United States)

    LeRouge, Cynthia; Wickramasinghe, Nilmini

    2013-07-01

    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.

  16. Cognitive Heterogeneous Reconfigurable Optical Networks (CHRON): Enabling Technologies and Techniques

    DEFF Research Database (Denmark)

    Tafur Monroy, Idelfonso; Zibar, Darko; Guerrero Gonzalez, Neil;

    2011-01-01

    We present the approach of cognition applied to heterogeneous optical networks developed in the framework of the EU project CHRON: Cognitive Heterogeneous Reconfigurable Optical Network. We introduce and discuss in particular the technologies and techniques that will enable a cognitive optical ne...

  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

    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

  18. Satellite Networks: Architectures, Applications, and Technologies

    Science.gov (United States)

    Bhasin, Kul (Compiler)

    1998-01-01

    Since global satellite networks are moving to the forefront in enhancing the national and global information infrastructures due to communication satellites' unique networking characteristics, a workshop was organized to assess the progress made to date and chart the future. This workshop provided the forum to assess the current state-of-the-art, identify key issues, and highlight the emerging trends in the next-generation architectures, data protocol development, communication interoperability, and applications. Presentations on overview, state-of-the-art in research, development, deployment and applications and future trends on satellite networks are assembled.

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

    Science.gov (United States)

    2009-03-01

    to the relatives of other users “I know people’s aunts and uncles that are on it and parents. It’s just kind of weird, so I made mine private... pressure and herding behavior, relaxed attitudes towards personal privacy, incomplete information, and faith in the networking service or members (Gross...following is an example of a free quotation from Respondent 9’ s interview. The bolded words are the words used to conduct the search, in this case, for

  20. Semi-Distributed Relay Selection Algorithm for Multi-User Cooperative Wireless Networks

    Directory of Open Access Journals (Sweden)

    Yafeng Wang

    2011-06-01

    Full Text Available In this paper, we propose a novel semi-distributed algorithm with low overhead and complexity for multi-user cooperative wireless networks with opportunistic relaying. The source is required to satisfy its minimum rate requirement with a feasible relay and help another source as a relay. The optimal solution can be obtained by exhaustive search with intractable computational complexity. Simulation results suggest that the proposed relay selection algorithm has the similar outage probability as the exhaustive search approach but with much less computational burden.

  1. Interference Cancellation at the Relay for Multi-User Wireless Cooperative Networks

    OpenAIRE

    Li, Liangbin; Jing, Yindi; Jafarkhani, Hamid

    2010-01-01

    We study multi-user transmission and detection schemes for a multi-access relay network (MARN) with linear constraints at all nodes. In a $(J, J_a, R_a, M)$ MARN, $J$ sources, each equipped with $J_a$ antennas, communicate to one $M$-antenna destination through one $R_a$-antenna relay. A new protocol called IC-Relay-TDMA is proposed which takes two phases. During the first phase, symbols of different sources are transmitted concurrently to the relay. At the relay, interference cancellation (I...

  2. Defense Switched Network Technology and Experiments Program.

    Science.gov (United States)

    2014-09-26

    3) development and test of data communication techniques using DoD-standard data protocols in an integrated voice /data network, and (4) EISN system... communication techniques using DoD-standard data protocols in an integrated voice /data network, and (4) EISN system coordination and experiment planning...control voice trunks that use E&M signaling and go from the RCP switch to the PCI or to another RCP switch; (e) A Dual- Tone Multiple-Frequency (DTMF

  3. User-based representation of time-resolved multimodal public transportation networks

    CERN Document Server

    Alessandretti, Laura; Gauvin, Laetitia

    2015-01-01

    Multimodal transportation systems can be represented as time-resolved multilayer networks where different transportation modes connecting the same set of nodes are associated to distinct network layers. Their quantitative description became possible recently due to openly accessible datasets describing the geolocalised transportation dynamics of large urban areas. Advancements call for novel analytics, which combines earlier established methods and exploits the inherent complexity of the data. Here, our aim is to provide a novel user-based methodological framework to represent public transportation systems considering the total travel time, its variability across the schedule, and taking into account the number of transfers necessary. Using this framework we analyse public transportation systems in several French municipal areas. We incorporate travel routes and times over multiple transportation modes to identify efficient transportation connections and non-trivial connectivity patterns. The proposed method ...

  4. Optimization of sensing time and cooperative user allocation for OR-rule cooperative spectrum sensing in cognitive radio network

    Institute of Scientific and Technical Information of China (English)

    刘鑫; 仲伟志; 陈琨奇

    2015-01-01

    In order to improve the throughput of cognitive radio (CR), optimization of sensing time and cooperative user allocation for OR-rule cooperative spectrum sensing was investigated in a CR network that includes multiple users and one fusion center. The frame structure of cooperative spectrum sensing was divided into multiple transmission time slots and one sensing time slot consisting of local energy detection and cooperative overhead. An optimization problem was formulated to maximize the throughput of CR network, subject to the constraints of both false alarm probability and detection probability. A joint optimization algorithm of sensing time and number of users was proposed to solve this optimization problem with low time complexity. An allocation algorithm of cooperative users was proposed to preferentially allocate the users to the channels with high utilization probability. The simulation results show that the significant improvement on the throughput can be achieved through the proposed joint optimization and allocation algorithms.

  5. Social Scholarship: Applying Social Networking Technologies to Research Practices

    Science.gov (United States)

    Greenhow, Christine

    2009-01-01

    Participatory web-based technologies have the potential to change the way scholars engage in scholarship. One reason Web 2.0 technologies, such as online social networking, are not widely integrated in PreK-12 and postsecondary education is the lack of modeling by educators. Their lack of research-based best practices limits the ability to…

  6. Key Technologies in the Context of Future Networks: Operational and Management Requirements

    Directory of Open Access Journals (Sweden)

    Lorena Isabel Barona López

    2016-12-01

    Full Text Available The concept of Future Networks is based on the premise that current infrastructures require enhanced control, service customization, self-organization and self-management capabilities to meet the new needs in a connected society, especially of mobile users. In order to provide a high-performance mobile system, three main fields must be improved: radio, network, and operation and management. In particular, operation and management capabilities are intended to enable business agility and operational sustainability, where the addition of new services does not imply an excessive increase in capital or operational expenditures. In this context, a set of key-enabled technologies have emerged in order to aid in this field. Concepts such as Software Defined Network (SDN, Network Function Virtualization (NFV and Self-Organized Networks (SON are pushing traditional systems towards the next 5G network generation.This paper presents an overview of the current status of these promising technologies and ongoing works to fulfill the operational and management requirements of mobile infrastructures. This work also details the use cases and the challenges, taking into account not only SDN, NFV, cloud computing and SON but also other paradigms.

  7. 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.

  8. A novel MLP network implementation in CMOL technology

    OpenAIRE

    Abdalhossein Rezai; Parviz Keshavarzi; Reza Mahdiye

    2014-01-01

    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...

  9. 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.

  10. 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.

  11. Security Service Technology for Mobile Networks

    Institute of Scientific and Technical Information of China (English)

    Aiqun Hu; Tao Li; Mingfu Xue

    2011-01-01

    As mobile networks become high speed and attain an all-IP structure, more services are possible. This brings about many new security requirements that traditional security programs cannot handle. This paper analyzes security threats and the needs of 3G/4G mobile networks, and then proposes a novel protection scheme for them based on their whole structure. In this scheme, a trusted computing environment is constructed on the mobile terminal side by combining software validity verification with access control. At the security management center, security services such as validity verification and integrity check are provided to mobile terminals. In this way, terminals and the network as a whole are secured to a much greater extent. This paper also highlights problems to be addressed in future research and development.

  12. Disclosure Management on Social Network Sites: Individual Privacy Perceptions and User-Directed Privacy Strategies

    Directory of Open Access Journals (Sweden)

    Philipp K. Masur

    2016-02-01

    Full Text Available The social web and specifically social network sites (SNS have offered new opportunities for interaction and communication, but have also increased the risk of privacy violations. In this study, we investigated how far users imply different disclosure management strategies in status updates and chat conversations. We hypothesized that users perceive specific information as differently private depending on their personal privacy preference, but generally show the same disclosure management pattern: the higher the perceived privacy level of an information, the less frequently it will be shared. We tested the hypothesis using an online survey with 316 German SNS users. The findings suggest that respondents engaged in disclosure management taking both communication channel and type of information into account. We further found that trust toward SNS contacts and use of privacy settings significantly influenced disclosure management in one-to-many (status updates but not in one-to-one communications situations (chat conversations. The results complement existing research by showing the pivotal role of individual privacy perceptions in explaining users’ privacy management in the social web.

  13. [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.

  14. 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.

  15. 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 OBJECTIVE: 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. METHODS: 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. RESULTS: 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. CONCLUSION: 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.

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

    NARCIS (Netherlands)

    Nasr, N.; Leon, B.; Mountain, G.A.; Nijenhuis, S.M.; Prange, G.B.; Sale, P.; Amirabdollahian, F

    2015-01-01

    Purpose: 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

  17. End-user searching: impetus for an expanding information management and technology role for the hospital librarian.

    OpenAIRE

    1997-01-01

    Using the results of the 1993 Medical Library Association (MLA) Hospital Libraries Section survey of hospital-based end-user search services, this article describes how end-user search services can become an impetus for an expanded information management and technology role for the hospital librarian. An end-user services implementation plan is presented that focuses on software, hardware, finances, policies, staff allocations and responsibilities, educational program design, and program eval...

  18. 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.

  19. network externalities into the technology acceptance model

    NARCIS (Netherlands)

    Song, Michael; Parry, Mark E.; Kawakami, Tomoko

    2009-01-01

    Research on network externalities has identified a number of product categories in which the market performance of an innovation (e.g., unit sales and revenues) is an increasing function of that innovation's installed base and the availability of complementary products. Innovation scholars have attr

  20. 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.

  1. North House : developing intelligent building technology and user interface in energy independent domestic environments

    Energy Technology Data Exchange (ETDEWEB)

    Velikov, K. [Waterloo Univ., Cambridge, ON (Canada). School of Architecture; Bartram, L. [Simon Fraser Univ., Surrey, BC (Canada). School of Interactive Arts and Technology

    2009-07-01

    This paper reported on the construction of the North House, a prototype solar-powered dwelling developed by a Canadian team for the 2009 Solar Decathlon. The prototype aims to develop a strategy for solar powered residential design that addresses the issues of how to build and live in the demanding northern context, how to design buildings that are adaptive to climate extremes and how new technologies and alternative energies can be used to create a viable and sustainable architecture. The occupant-focused design is meant to empower the occupants with both knowledge and control so that they can make intelligent choices and transform their own habits to live more sustainably. The residential occupant needs to operate as both user and manager of a green dwelling, and therefore requires specific information as well as access to help the building work more efficiently. The domestic environment is different from a workplace environment and therefore requires a unique means of control, display and integration with user lifestyle. The Adaptive Living Interface System for North House is based on interactive technologies that help occupants to both control the systems of the house while providing feedback on the operation of the house. The objective is to support behavioural transformation for energy saving living patterns. Once the competition is over, the North House will be reinstalled in Canada to undergo a minimum of 2 years of post-occupancy evaluation (POE) and testing. Both quantitative and qualitative data will be collected on energy performance, user livability, comfort and user satisfaction. Results were be measured against performance simulation during the design phase and will be used to provide feedback on simulation software. 11 refs., 5 figs.

  2. 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…

  3. The Usability Evaluation of Fakih Method Based on Technology for Students with Hearing Difficulties: The User's Retrospective

    Science.gov (United States)

    Sabdan, Muhammad Sayuti Bin; Alias, Norlidah; Jomhari, Nazean; Jamaludin, Khairul Azhar; DeWitt, Dorothy

    2014-01-01

    The study is aimed at evaluating the FAKIH method based on technology in teaching al-Quran, based on the user's retrospective. The participants of this study were five students selected based on hearing difficulties. The study employed the user evaluation framework. Teacher's journals were used to determine the frequency and percentage of…

  4. 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…

  5. 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…

  6. 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…

  7. User 2020

    DEFF Research Database (Denmark)

    Porras, Jari; Heikkinen, Kari; Kinnula, Marianne

    2014-01-01

    and environment, and each has had its effect on the development of technology. The closer we come to the current generation, the bigger is the effect of technology on the characteristics of that generation. User needs guide the technology and the technology shapes the users. This WWRF Outlook analyses......The User 2020 vision is of the changing needs and habits of a user in the future digital world. In order to understand the needs of the future users, we need to look at how users and technology have changed during recent years. The different generations of users are products of their own time...... determined by the era in which they were born. This is due to the fact that digital natives, born in an already “fully” digitalized world with a plethora of ICT services, have a much closer relationship to these solutions than generations before them. This has also shaped the users perspectives and had...

  8. 75 FR 57521 - Networking and Information Technology Research and Development (NITRD) Program: Draft NITRD 2010...

    Science.gov (United States)

    2010-09-21

    ... FOUNDATION Networking and Information Technology Research and Development (NITRD) Program: Draft NITRD 2010 Strategic Plan--URL Correction AGENCY: The National Coordination Office (NCO) for Networking and Information... Coordination Office for Networking and Information Technology Research and Development (NITRD)...

  9. Design and Implementation of User Relationship Mining in Social Networking Services Website%SNS网站用户关系挖掘的设计与实现

    Institute of Scientific and Technical Information of China (English)

    陈清华; 李林锦; 翁正秋

    2011-01-01

    针对目前网络社交网站存在的交友形式单薄、好友关系淡化、用户流失等问题,设计基于"寝室"组织形式的社交网站系统,嵌入用户挖掘模块,通过权值更新和潜在关系更新算法帮助用户寻找潜在好友,以达到拓展社交圈的目的.实验结果表明,该系统的好友推荐准确度较高.%With the wide application of Internet and computer technology, online social networking service becomes one of the best means to keep contacts with old friends and to make new friends. However, there are still many shortages in Social Networking Services(SNS), such as user relationship deterioration and user loss. In order to solve these problems, this paper proposes a SNS website system based on "dormitory". A module of user relationship mining is embedded to help users to get their potential friends in advance by weight and potential relationship updating.Experimental results show that this system achieves a good recommending accuracy.

  10. 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

  11. Characterization of users of remotely-sensed data in the Alabama coastal zone. [user requirements, surveys - technology utilization

    Science.gov (United States)

    Vittor, B. A. (Editor)

    1975-01-01

    Federal, State, local, universities and private companies were polled to determine their needs for remote sensing data. A total of 62 users were polled. Poll results are given in tables. A comprehensive research program was developed to satisfy user needs, and is examined for the disciplines of Geology, Water Resources, Archaeology, Geography, and Conservation. An investigation of silt plume discharge from Mobile Bay is also examined. Sample poll forms used in the surveys are shown.

  12. 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.

  13. Networks dynamics in the case of emerging technologies

    Energy Technology Data Exchange (ETDEWEB)

    Rotolo, D

    2016-07-01

    This research in progress aims at increasing our understanding of how collaborative networks form, evolve and are configured in the case of emerging technologies. The architecture of the relationships among the variety of organisational actors involved in the emergence process exerts a significant influence in shaping technological change in certain directions rather than others, especially in the early stage of emergence. As a result, socially optimal or desirable technological trajectories may be ‘opportunistically’ rejected. Our empirical analysis is based on a case-study of an emerging medical technology, namely ‘microneedles’. On the basis of co-authorship data reported in 1,943 publications on the topic from 1990 to 2014, longitudinal collaboration (co-authorship) networks were built at two levels: affiliation and author. We examined the dynamics of co-authorship networks by building on recent methodological advancements in network analysis, i.e. Exponential Random Graph Models (ERGMs). These models enable us to make statistical inferences about on the extent to which a network configuration occurs more than could be expected by chance and to identify which social mechanisms may be shaping the network in certain configurations. The findings of the statistical analyses (currently in progress) combined with the qualitative understanding of the case will increase our understanding of which mechanisms are more likely to drive the network dynamics in the case of emerging technologies. These include evidence of the extent to which the likelihood of forming, maintaining, or terminating ties among actors (authors or affiliations) is affected by actors’ covariates such as types of organisations, diversity/specialisation of the research undertaken, and status. These findings have potential to provide important inputs for policymaking process in the case of emerging technologies. (Author)

  14. Energy-Efficient User Association Strategy for Hyperdense Heterogeneous Networking in the Fifth Generation Systems

    Directory of Open Access Journals (Sweden)

    Lei Li

    2015-01-01

    Full Text Available Redesigning user association strategies to improve energy efficiency (EE has been viewed as one of the promising shifting paradigms for the fifth generation (5G cellular networks. In this paper, we investigate how to optimize users’ association to enhance EE for hyper dense heterogeneous networking in the 5G cellular networks, where the low-power node (LPN much outnumbers the high-power node (HPN. To characterize that densely deployed LPNs would undertake a majority of high-rate services, while HPNs mainly support coverage; the EE metric is defined as average weighted EE of access nodes with the unit of bit per joule. Then, the EE optimization objective function is formulated and proved to be nonconvex. Two mathematical transformation techniques are presented to solve the nonconvex problem. In the first case, the original problem is reformulated as an equivalent problem involving the maximization of a biconcave function. In the second case, it is equivalent to a concave minimization problem. We focus on the solution of the biconcave framework, and, by exploiting the biconcave structure, a novel iterative algorithm based on dual theory is proposed, where a partially optimal solution can be achieved. Simulation results have verified the effectiveness of the proposed algorithm.

  15. Networks and network resources in technological innovation systems : Towards a conceptual framework for system building

    NARCIS (Netherlands)

    Musiolik, J.; Markard, J.; Hekkert, M.P.

    2012-01-01

    Previous research has shown that formal networks can play a crucial role in the formation of technological innovation systems (TIS). Firms and other actors collaborate in formal networks not only to generate new knowledge but also to strategically create and shape supportive system resources such as

  16. 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.

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

    Science.gov (United States)

    2011-04-28

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

  19. 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...

  20. Effects of Beliefs and Concerns on User Attitudes toward Online Social Network Advertising and Their Ad Clicking Behavior

    Directory of Open Access Journals (Sweden)

    Imran Mir

    2015-08-01

    Full Text Available Since last few years social network sites (SNSs have rapidly grown in popularity and user acceptance globally. They have become the main place for social interaction, discussion and communication. Today, many businesses advertise their products on SNSs. The current study aims to assess the effects of SNSs consumers/users’ beliefs and concerns of social network advertising (SNA on their attitudes toward SNA and SNS banner ad-clicking behavior. Data was collected from a sample of 397 university students of Pakistan. Results show the beliefs of SNA as informative and entertaining have positive effects on user attitudes toward SNA and their ad-clicking behavior. Similarly, user concern of SNA as irritating has negative effects on both their attitudes toward SNA and ad-clicking behavior. Good for economy is an important socioeconomic belief which affects user attitudes toward SNA positively. The overall results indicate that utilitarian and hedonic aspects of SNA make SNS banner ads effective.

  1. 3G无线网络条件下的用户行为分析%ANALYSING USERS BEHAVIOUR IN 3G WIRELESS NETWORKS

    Institute of Scientific and Technical Information of China (English)

    胡俊华; 魏芳; 平金玉

    2012-01-01

    With the rapid development of wireless communication technology and computer network technology, it becomes the urgent need for broad range of users to fast and effectively access the internet with mobile portable devices, and the acquaintance and analysis on the behaviour pattern of wireless network user becomes very necessary. In this paper we record the data of users in a residential zone who surfing internet through 3G wireless network,the processed data is used as the basis to estimate the relations between the data and to derive potential relationship of time-varied network traffic,IP number and user number, then further work out the active index which reflects the behaviour habit of wireless internet users. The analyses results provide the base in data for the amelioration and improvement of performance of wireless internet as well as for the reasonable decision of wireless network service provider,therefore have significant commercial value.%随着无线通信技术和计算机网络技术的快速发展,通过移动手持设备快速有效地接入互联网成为广大用户的迫切需求,了解和分析无线用户的行为模式显得十分必要.对一个小区内通过3G无线上网用户的数据进行记录,处理后以此为基础估计数据之间的关系,得出流量、IP数和用户数之间随着时间变化的潜在关系,进一步得出反映无线互联网用户行为习惯的活跃指数.分析结果为无线互联网的性能的改进和提高,以及无线网络服务商合理决策提供了数据依据,具有重要的商业价值.

  2. Network Stack Analyzing and Protocol Add Technology in Linux%Linux网络协议栈分析及协议添加的实现

    Institute of Scientific and Technical Information of China (English)

    唐续; 刘心松; 杨峰

    2003-01-01

    In order to improve the performance of Linux network,new protocols should be implemented and added in original protocol stack. For this demand,this paper has analyzed Linux network stack architecture and implement technology,then presented a method that appended new protocols in the network stack of Linux. The processes of protocol register ,protocol operation,protocol header implement,packets receiving, user interface are involved in this method.

  3. User Localization in Complex Environments by Multimodal Combination of GPS, WiFi, RFID, and Pedometer Technologies

    OpenAIRE

    Trung-Kien Dao; Hung-Long Nguyen; Thanh-Thuy Pham; Eric Castelli; Viet-Tung Nguyen; Dinh-Van Nguyen

    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 localiz...

  4. Policy and Technology Readiness: Engaging the User and Developer Community to Develop a Research Roadmap

    Energy Technology Data Exchange (ETDEWEB)

    Olson, Jarrod; Barr, Jonathan L.; Burtner, Edwin R.; West, Curtis L.; Kielman, Joseph

    2015-05-16

    A key challenge for research roadmapping in the crisis response and management domain is articulation of a shared vision that describes what the future can and should include. Visioning allows for far-reaching stakeholder engagement that can properly align research with stakeholders needs. Engagement includes feedback from researchers, policy makers, general public, and end-users on technical and non-technical factors. This work articulates a process and framework for the construction and maintenance of a stakeholder-centric research vision and roadmap in the emergency management domain. This novel roadmapping process integrates three pieces: analysis of the research and technology landscape, visioning, and stakeholder engagement. Our structured engagement process elicits research foci for the roadmap based on relevance to stakeholder mission, identifies collaborators, and builds consensus around the roadmap priorities. We find that the vision process and vision storyboard helps SMEs conceptualize and discuss a technology's strengths, weaknesses, and alignment with needs

  5. 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.

  6. 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.

  7. Disruptive technologies and networking in telecom industries

    OpenAIRE

    Madsen, Erik Strøjer; Hartington, Simon

    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 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 su...

  8. The Technology of Wireless Local Area Network

    Institute of Scientific and Technical Information of China (English)

    林楠; 李翠霞

    2007-01-01

    This article provides an overview of the Wireless LAN. Firstly, the article introduces the history ofdevelopment of IEEE 802.11.Then, the article will discuss the basic technology of the IEEE 802.11 including IEEE 802.11b, a, and g. The finally, IEEE 802.11 a / b / gComparison and the trend of WLANs will be prospected by this article.

  9. 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...

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

    Science.gov (United States)

    Skardal, Per Sebastian; Arenas, Alex

    2015-08-01

    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.

  11. Traffic-Adaptive Proactive Sp ectrum Handoff Strategy for Graded Secondary Users in Cognitive Radio Networks

    Institute of Scientific and Technical Information of China (English)

    ZHANG Lei; SONG Tiecheng; WU Ming; BAO Xu; GUO Jie; HU Jing

    2015-01-01

    In order to meet diff erent delay require-ments of various communication services in Cognitive ra-dio (CR) networks, Secondary users (SUs) are divided into two classes according to the priority of accessing to spec-trum in this paper. Based on the proactive spectrum hand-off scheme, the Preemptive resume priority (PRP) M/G/1 queueing is used to characterize multiple spectrum hand-off s under two diff erent spectrum handoff strategies. The traffic-adaptive spectrum handoff strategy is proposed for graded SUs so as to minimize the average cumulative hand-off delay. Simulation results not only verify that our theo-retical analysis is valid, but also show that the strategy we proposed can reduce the average cumulative handoff delay evidently. The eff ect of service rate on the proposed spec-trum switching point and the admissible access region are provided.

  12. 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.

  13. 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

  14. 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.

  15. 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

  16. Technology and media preferences: Results from some user studies in Albanian public libraries

    Directory of Open Access Journals (Sweden)

    Athina Basha

    2014-08-01

    Full Text Available The paper studies the state of awareness of information literacy and media literacy in Albania and the role of libraries in raising their capacity in fostering use of technology and media and practicing polices of life-long learning (LLL and education. There is an urgent need in Albania to raise the awareness of information and media literacy issues in the new realities and the skills needed to navigate, evaluate, and use information and technology. The role of the libraries and other institutions is of great importance and impact when it comes to assisting users of all levels not only to find but also to evaluate and use information properly for professional and daily life decisions. This research and the surveys done in Fier Public Library during 1995-2012, will bring a contribution to a greater understanding of the situation in most of the public libraries in Albania and the impact that information, media, and new technologies have in our daily life. The purpose of the research is to raise the awareness of all the stakeholders in Albanian society on its importance for future development. The research has shown that libraries, librarians, and other stakeholders of the society lack understanding on information and media literacy as well as the right infrastructure to support the development of information and communication technology (ICT.

  17. 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, pnetworking 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.

  18. PAD-MAC: primary user activity-aware distributed MAC for multi-channel cognitive radio networks.

    Science.gov (United States)

    Ali, Amjad; Piran, Md Jalil; Kim, Hansoo; Yun, Jihyeok; Suh, Doug Young

    2015-03-30

    Cognitive radio (CR) has emerged as a promising technology to solve problems related to spectrum scarcity and provides a ubiquitous wireless access environment. CR-enabled secondary users (SUs) exploit spectrum white spaces opportunistically and immediately vacate the acquired licensed channels as primary users (PUs) arrive. Accessing the licensed channels without the prior knowledge of PU traffic patterns causes severe throughput degradation due to excessive channel switching and PU-to-SU collisions. Therefore, it is significantly important to design a PU activity-aware medium access control (MAC) protocol for cognitive radio networks (CRNs). In this paper, we first propose a licensed channel usage pattern identification scheme, based on a two-state Markov model, and then estimate the future idle slots using previous observations of the channels. Furthermore, based on these past observations, we compute the rank of each available licensed channel that gives SU transmission success assessment during the estimated idle slot. Secondly, we propose a PU activity-aware distributed MAC (PAD-MAC) protocol for heterogeneous multi-channel CRNs that selects the best channel for each SU to enhance its throughput. PAD-MAC controls SU activities by allowing them to exploit the licensed channels only for the duration of estimated idle slots and enables predictive and fast channel switching. To evaluate the performance of the proposed PAD-MAC, we compare it with the distributed QoS-aware MAC (QC-MAC) and listen-before-talk MAC schemes. Extensive numerical results show the significant improvements of the PAD-MAC in terms of the SU throughput, SU channel switching rate and PU-to-SU collision rate.

  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. 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.

  1. Multi-channel electromyography pattern classification using deep belief networks for enhanced user experience

    Institute of Scientific and Technical Information of China (English)

    SHIM Hyeon-min; LEE Sangmin

    2015-01-01

    An enhanced algorithm is proposed to recognize multi-channel electromyography (EMG) patterns using deep belief networks (DBNs). It is difficult to classify the EMG features because an EMG signal has nonlinear and time-varying characteristics. Therefore, in several previous studies, various machine-learning methods have been applied. A DBN is a fast, greedy learning algorithm that can find a fairly good set of weights rapidly, even in deep networks with a large number of parameters and many hidden layers. To evaluate this model, we acquired EMG signals, extracted their features, and then compared the model with the DBN and other conventional classifiers. The accuracy of the DBN is higher than that of the other algorithms. The classification performance of the DBN model designed is approximately 88.60%. It is 7.55% (p=9.82×10-12) higher than linear discriminant analysis (LDA) and 2.89% (p=1.94×10-5) higher than support vector machine (SVM). Further, the DBN is better than shallow learning algorithms or back propagation (BP), and this model is effective for an EMG-based user-interfaced system.

  2. 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

  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. Network Technologies for Networked Terrorists: Assessing the Value of Information and Communication Technologies to Modern Terrorist Organizations

    Science.gov (United States)

    2007-01-01

    society’s essential physical assets and natural resources and to enhance the related social assets of safety and security of individuals in transit...relay chat LTTE Liberation Tigers of Tamil Eelam MIT Massachusetts Institute of Technology MMOG massively multiplayer online game MRTA Movimiento ...Technologies for Networked Terrorists Developing a strategy: Terrorist actions are intended to accomplish political or social goals. To guide its actions, a

  6. Research information network survey of innovative technology for the earth. 2; Chikyu kankyo taisaku gijutsu no kenkyu joho network chosa. 2

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-03-01

    In order to construct the information network system for a research of innovative technology for the earth, a prototype has been made. To draw necessary functions for the information network system, an information flow in a general research work is analyzed to classify it based on the functions. The information collecting function, information accumulating and sharing function, special information system for research, information providing function, and communication function of the net work correspond to the collecting information, accumulating information, being engaged in research, providing information, and communication of researcher`s actions, respectively. The services on network system supposed from these functions are the homepage search mailing list, intranet service, special information system for research, WWW Internet broadcasting, and BBS/news/conference tool, respectively. It was found that latest Internet technology enabled to construct easily controlled system environment for users and WWW would develop as a standard communication tool. 2 refs., 26 figs., 27 tabs.

  7. DEEP WEB USERS DEANONIMIZATION SYSTEM

    OpenAIRE

    AVDOSHIN S.M.; LAZARENKO A.V.

    2016-01-01

    Privacy enhancing technologies (PETs) are ubiquitous nowadays. They are beneficial for a wide range of users: for businesses, journalists, bloggers, etc. However, PETs are not always used for legal activity. There a lot of anonymous networks and technologies which grants anonymous access to digital resources. The most popular anonymous networks nowadays is Tor. Tor is a valuable tool for hackers, drug and gun dealers. The present paper is focused on Tor users’ deanonimization using out-of-the...

  8. Collaboration Between Researchers and Knowledge Users in Health Technology Assessment: A Qualitative Exploratory Study

    Directory of Open Access Journals (Sweden)

    Mylène Tantchou Dipankui

    2017-08-01

    Full Text Available Background Collaboration between researchers and knowledge users is increasingly promoted because it could enhance more evidence-based decision-making and practice. These complex relationships differ in form, in the particular goals they are trying to achieve, and in whom they bring together. Although much is understood about why partnerships form, relatively little is known about how collaboration works: how the collaborative process is shaped through the partners’ interactions, especially in the field of health technology assessment (HTA? This study aims at addressing this gap in the literature in the specific context of HTA. Methods We used a qualitative descriptive design for this exploratory study. Semi-structured interviews with three researchers and two decision-makers were conducted on the practices related to the collaboration. We also performed document analysis, observation of five team meetings, and informal discussion with the participants. We thematically analyzed data using the structuration theory and a collective impact (CI framework. Results This study showed that three main contextual factors helped shape the collaboration between researchers and knowledge users: the use of concepts related to each field; the use of related expertise; and a lack of clearly defined roles in the project. Previous experiences with the topic of the research project and a partnership based on “a give and take” relationship emerged as factors of success of this collaboration. Conclusion By shedding light on the structuration of the collaboration between researchers and knowledge users, our findings open the door to a poorly documented field in the area of HTA, and additional studies that build on these early observations are welcome.

  9. An Anonymous User Authentication and Key Agreement Scheme Based on a Symmetric Cryptosystem in Wireless Sensor Networks

    Science.gov (United States)

    Jung, Jaewook; Kim, Jiye; Choi, Younsung; Won, Dongho

    2016-01-01

    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. PMID:27537890

  10. 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.

  11. 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.

  12. An Anonymous User Authentication and Key Agreement Scheme Based on a Symmetric Cryptosystem in Wireless Sensor Networks.

    Science.gov (United States)

    Jung, Jaewook; Kim, Jiye; Choi, Younsung; Won, Dongho

    2016-08-16

    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.

  13. 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.

  14. Touch Interaction with 3D Geographical Visualization on Web: Selected Technological and User Issues

    Science.gov (United States)

    Herman, L.; Stachoň, Z.; Stuchlík, R.; Hladík, J.; Kubíček, P.

    2016-10-01

    The use of both 3D visualization and devices with touch displays is increasing. In this paper, we focused on the Web technologies for 3D visualization of spatial data and its interaction via touch screen gestures. At the first stage, we compared the support of touch interaction in selected JavaScript libraries on different hardware (desktop PCs with touch screens, tablets, and smartphones) and software platforms. Afterward, we realized simple empiric test (within-subject design, 6 participants, 2 simple tasks, LCD touch monitor Acer and digital terrain models as stimuli) focusing on the ability of users to solve simple spatial tasks via touch screens. An in-house testing web tool was developed and used based on JavaScript, PHP, and X3DOM languages and Hammer.js libraries. The correctness of answers, speed of users' performances, used gestures, and a simple gesture metric was recorded and analysed. Preliminary results revealed that the pan gesture is most frequently used by test participants and it is also supported by the majority of 3D libraries. Possible gesture metrics and future developments including the interpersonal differences are discussed in the conclusion.

  15. The bond as a soft technology in the daily routine of the Family Health Strategy: perception of the user

    Directory of Open Access Journals (Sweden)

    Bianca Pozza dos Santos

    Full Text Available Objective.This study aimed to analyze the production of a bond between users and health care professionals in a Family Health Unit (FHU. Methods. This was a qualitative, descriptive study, with 33 hypertensive and/or diabetic users. Interviews were transcribed, analyzed and data were compared to the literature. Results. The users who have been accessing the FHU for years stated that the bond with professionals has grown weak, it is a fragile bond. When it does exist, it is directed toward some professionals in the team. A disruption in the bond was also mentioned in some situations, owing to individual issues. Establishment of a bond between the user and the health care professionals in the reference FHU consists of a soft technology. Therefore, it impacts quality of health care and the prevention and management of chronic diseases. Conclusion. Establishment of a bond is essential for health care professionals to become references for the users of health care services.

  16. 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.

  17. 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.

  18. Applying Network Technology to Improve TV News Production Mode

    Institute of Scientific and Technical Information of China (English)

    冷劲松; 林成栋

    2003-01-01

    With the development of database and computer network technology, traditional TV news production mode (TVNPM) faces great challenge. Up to now, evolution of TVNPM has experienced two stages: In the beginning, TV news is produced completely by hand, named as pipelining TVNPM in this paper. This production mode is limited to space and time, so its production cycle is very time-consuming, and it requires a lot of harmony in different departments; Subsequently, thanks to applications of database technology, a new TVNPM appears, which is named as pooled information resource TVNPM. Compared with pipelining TVNPM, this mode promotes information sharing. However, with the development of network technology, especially the Intranet and the Internet, the pooled information resource TVNPM receives strong impact, and it is referred to contrive a new TVNPM. This new TVNPM must support information sharing, remote collaboration, and interaction in communications so as to improve group work efficiency. In this paper, we present such a new TVNPM, namely, Network TVNPM, give a suit of system solution to support the new TVNPM, introduce the new workflow, and in the end analyze the advantages of Network TVNPM.

  19. P2P Networking and Technology Enablers in Business Applications

    OpenAIRE

    Hariharan, Mahesh

    2006-01-01

    The usage of Peer to Peer Networks over the Internet has been growing by exponentially. Apartbfrom the hype surrounding P2P, it has remarkable ramifications on the way the Internet could be used. This is an area which is not explored as well as we would want to. This thesis examines the architectural differences in P2P networks and generic application domains where the principles of P2P are exploited. The usage of P2P in different business verticals and technology enablers that go along with ...

  20. Comparison Study of Transmission Control Protocol and User Datagram Protocol Behavior over Multi-Protocol Label Switching Networks in Case of Failures

    Directory of Open Access Journals (Sweden)

    Taha A.A Radaei

    2009-01-01

    Full Text Available Problem statement: In only a few years, Multi-Protocol Label Switching (MPLS has evolved from an exotic technology to a mainstream tool used by service providers to create revenue-generating services. MPLS provides a high reliable Label Switched Path (LSP. MPLS failures may degrade the reliability of the MPLS networks. Approach: For that reason, many studies have been conducted to keep the high reliability and survivability of the MPLS networks. Unlike User Datagram Protocol (UDP, Transmission Control Protocol does not perform well in case of like-failure of MPLS networks because of its inability to distinguish packet loss due to link-failure. After the recovery time, TCP takes longer time than UDP to continue as it was before the failure. Results: In terms of packet loss, TCP performs better than UDP. However, the receiving rate of the TCP traffic is much worse than UDP traffic. A need for a mechanism to improve the behavior of TCP after a link failure is needed. This study focused on comparing the behavior of different types TCP as well as UDP traffic over MPLS networks in case of link, node or congestion failures. Conclusion: Although extensions of RSVP-TE protocol support fast recovery mechanism of MPLS networks, the behavior of TCP will be affected during recovery time much more than with UDP.