WorldWideScience

Sample records for feedback-based online network

  1. Multiple Description Coding with Feedback Based Network Compression

    DEFF Research Database (Denmark)

    Sørensen, Jesper Hemming; Østergaard, Jan; Popovski, Petar

    2010-01-01

    and an intermediate node, respectively. A trade-off exists between reducing the delay of the feedback by adapting in the vicinity of the receiver and increasing the gain from compression by adapting close to the source. The analysis shows that adaptation in the network provides a better trade-off than adaptation...

  2. An Enhanced Feedback-Base Downlink Packet Scheduling Algorithm for Mobile TV in WIMAX Networks

    OpenAIRE

    Oyewale, Joseph; Xiao Juan, Liu

    2013-01-01

    With high speed access network technology like WIMAX, there is the need for efficient management of radio resources where the throughput and Qos requirements for Multicasting Broadcasting Services (MBS) for example TV are to be met. An enhanced  feedback-base downlink Packet scheduling algorithm  that can be used in IEEE 802.16d/e networks for mobile TV “one way traffic”(MBS) is needed to support many users utilizing multiuser diversity of the  broadband of WIMAX systems where a group of user...

  3. An Enhanced Feedback-Base Downlink Packet Scheduling Algorithm for Mobile TV in WIMAX Networks

    Directory of Open Access Journals (Sweden)

    Joseph Oyewale

    2013-06-01

    Full Text Available With high speed access network technology like WIMAX, there is the need for efficient management of radio resources where the throughput and Qos requirements for Multicasting Broadcasting Services (MBS for example TV are to be met. An enhanced  feedback-base downlink Packet scheduling algorithm  that can be used in IEEE 802.16d/e networks for mobile TV “one way traffic”(MBS is needed to support many users utilizing multiuser diversity of the  broadband of WIMAX systems where a group of users(good/worst channels share allocated resources (bandwidth. This paper proposes a WIMAX framework feedback-base (like a channel-awareness downlink packet scheduling algorithm for Mobile TV traffics in IEEE806.16, in which network Physical Timing Slots (PSs resource blocks are allocated in a dynamic way to mobile TV subscribers based on the Channel State information (CSI feedback, and then considering users with worst channels with the aim of improving system throughput while system coverage is being guaranteed. The algorithm was examined by changing the PSs bandwidth allocation of the users and different number of users of a cell. Simulation results show our proposed algorithm performed better than other algorithms (blind algorithms in terms of improvement in system throughput performance. /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso

  4. Decentralized Online Social Networks

    Science.gov (United States)

    Datta, Anwitaman; Buchegger, Sonja; Vu, Le-Hung; Strufe, Thorsten; Rzadca, Krzysztof

    Current Online social networks (OSN) are web services run on logically centralized infrastructure. Large OSN sites use content distribution networks and thus distribute some of the load by caching for performance reasons, nevertheless there is a central repository for user and application data. This centralized nature of OSNs has several drawbacks including scalability, privacy, dependence on a provider, need for being online for every transaction, and a lack of locality. There have thus been several efforts toward decentralizing OSNs while retaining the functionalities offered by centralized OSNs. A decentralized online social network (DOSN) is a distributed system for social networking with no or limited dependency on any dedicated central infrastructure. In this chapter we explore the various motivations of a decentralized approach to online social networking, discuss several concrete proposals and types of DOSN as well as challenges and opportunities associated with decentralization.

  5. Online social support networks.

    Science.gov (United States)

    Mehta, Neil; Atreja, Ashish

    2015-04-01

    Peer support groups have a long history and have been shown to improve health outcomes. With the increasing familiarity with online social networks like Facebook and ubiquitous access to the Internet, online social support networks are becoming popular. While studies have shown the benefit of these networks in providing emotional support or meeting informational needs, robust data on improving outcomes such as a decrease in health services utilization or reduction in adverse outcomes is lacking. These networks also pose unique challenges in the areas of patient privacy, funding models, quality of content, and research agendas. Addressing these concerns while creating patient-centred, patient-powered online support networks will help leverage these platforms to complement traditional healthcare delivery models in the current environment of value-based care.

  6. Online Advertising in Social Networks

    Science.gov (United States)

    Bagherjeiran, Abraham; Bhatt, Rushi P.; Parekh, Rajesh; Chaoji, Vineet

    Online social networks offer opportunities to analyze user behavior and social connectivity and leverage resulting insights for effective online advertising. This chapter focuses on the role of social network information in online display advertising.

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

    Directory of Open Access Journals (Sweden)

    Guiyi Wei

    2010-10-01

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

  8. Foraging Online Social Networks

    NARCIS (Netherlands)

    Koot, G.; Huis in ’t Veld, M.A.A.; Hendricksen, J.; Vries, A. de; Broek, E.L. van den

    2014-01-01

    A concise and practical introduction is given on Online Social Networks (OSN) and their application in law enforcement, including a brief survey of related work. Subsequently, a tool is introduced that can be used to search OSN in order to generate user profiles. Both its architecture and processing

  9. LHCb Online Networking Requirements

    CERN Document Server

    Jost, B

    2003-01-01

    This document describes the networking requirements of the LHCb online installation. It lists both quantitative aspects such as the number of required switch ports, as well as some qualitative features of the equipment, such as minimum buffer sizes in switches. The document comprises both the data acquisition network and the controls/general-purpose network. While the numbers represent our best current knowledge and are intended to give (in particular) network equipment manufacturers an overview of our needs, this document should not be confused with a market survey questionnaire or a formal tendering document. However the information contained in this document will be the input of any such document. A preliminary schedule for procurement and installation is also given.

  10. Strategic Networking for Online Success

    OpenAIRE

    Heitmann, M; Bremer, L; Stahl, F; Ansari, A

    2010-01-01

    The growth of online social networks and the decreasing effectiveness of traditional marketing have lead to a large interest in social networks. For an appropriate application of new marketing approaches marketers have to understand the impact of interactions and relationships among network members on their individual outcome and network popularity in order to use online social networks effectively in marketing. In this study we analyze networking behavior of music artists for promoting their...

  11. Online social networking for radiology.

    Science.gov (United States)

    Auffermann, William F; Chetlen, Alison L; Colucci, Andrew T; DeQuesada, Ivan M; Grajo, Joseph R; Heller, Matthew T; Nowitzki, Kristina M; Sherry, Steven J; Tillack, Allison A

    2015-01-01

    Online social networking services have changed the way we interact as a society and offer many opportunities to improve the way we practice radiology and medicine in general. This article begins with an introduction to social networking. Next, the latest advances in online social networking are reviewed, and areas where radiologists and clinicians may benefit from these new tools are discussed. This article concludes with several steps that the interested reader can take to become more involved in online social networking. Copyright © 2015 AUR. Published by Elsevier Inc. All rights reserved.

  12. Privacy in Online Social Networks

    NARCIS (Netherlands)

    Beye, Michael; Jeckmans, Arjan; Erkin, Zekeriya; Erkin, Zekeriya; Hartel, Pieter H.; Lagendijk, Reginald; Tang, Qiang; Abraham, A.

    Online Social Networks (OSNs) have become part of daily life for millions of users. Users building explicit networks that represent their social relationships and often share a wealth of personal information to their own benefit. The potential privacy risks of such behavior are often underestimated

  13. Measurement of Online Social Networks

    Science.gov (United States)

    Gjoka, Mina

    2010-01-01

    In recent years, the popularity of online social networks (OSN) has risen to unprecedented levels, with the most popular ones having hundreds of millions of users. This success has generated interest within the networking community and has given rise to a number of measurement and characterization studies, which provide a first step towards their…

  14. Modeling online social signed networks

    Science.gov (United States)

    Li, Le; Gu, Ke; Zeng, An; Fan, Ying; Di, Zengru

    2018-04-01

    People's online rating behavior can be modeled by user-object bipartite networks directly. However, few works have been devoted to reveal the hidden relations between users, especially from the perspective of signed networks. We analyze the signed monopartite networks projected by the signed user-object bipartite networks, finding that the networks are highly clustered with obvious community structure. Interestingly, the positive clustering coefficient is remarkably higher than the negative clustering coefficient. Then, a Signed Growing Network model (SGN) based on local preferential attachment is proposed to generate a user's signed network that has community structure and high positive clustering coefficient. Other structural properties of the modeled networks are also found to be similar to the empirical networks.

  15. Online Social Network Interactions:

    Directory of Open Access Journals (Sweden)

    Hui-Jung Chang

    2018-01-01

    Full Text Available A cross-cultural comparison of social networking structure on McDonald’s Facebook fan sites between Taiwan and the USA was conducted utilizing the individualism/collectivism dimension proposed by Hofstede. Four network indicators are used to describe the network structure of McDonald’s Facebook fan sites: size, density, clique and centralization. Individuals who post on both Facebook sites for the year of 2012 were considered as network participants for the purpose of the study. Due to the huge amount of data, only one thread of postings was sampled from each month of the year of 2012. The final data consists of 1002 postings written by 896 individuals and 5962 postings written by 5532 individuals from Taiwan and the USA respectively. The results indicated that the USA McDonald’s Facebook fan network has more fans, while Taiwan’s McDonald’s Facebook fan network is more densely connected. Cliques did form among the overall multiplex and within the individual uniplex networks in two countries, yet no significant differences were found between them. All the fan networks in both countries are relatively centralized, mostly on the site operators.

  16. Barter Online Network

    Directory of Open Access Journals (Sweden)

    Van Ngoc Tran

    2015-12-01

    Full Text Available Barter is the direct exchange of goods or services without using a medium of exchange, such as money. Barter faced a number of limitations, and according to Smith (1776, these limitations led to the emergence of money. However, trading with money also exposes traders to the problems of monetary economy such as inflation, deflation, currency de-valuation, and currency exchange fluctuation. According to Statista.com (2015, in 2016, global Business to Customer (B2C e-commerce sales will reach 1.92 trillion US dollars. On the other hand, online barter solutions are rare on the market. The only attempts to tackle online barter are mobile applications, carried out by small businesses. The market gap is caused by the unsolved inefficiencies of barter. The aim of this thesis is to identify the problems of barter, propose an IT solution for the problems of barter, and finally, produce an artefact, which is the realisation of the proposed IT solution by utilising computer systems and computer algorithms.

  17. What Online Networks Offer: Online Network Compositions and Online Learning Experiences of Three Ethnic Groups

    NARCIS (Netherlands)

    Lecluijze, Susanne Elisabeth; de Haan, M.J.; Ünlüsoy, A.

    2015-01-01

    This exploratory study examines ethno-cultural diversity in youth ́s narratives regarding their online learning experiences while also investigating how these narratives can be understood from the analysis of their online network structure and composition. Based on ego-network data of 79 respondents

  18. Recommendation in evolving online networks

    Science.gov (United States)

    Hu, Xiao; Zeng, An; Shang, Ming-Sheng

    2016-02-01

    Recommender system is an effective tool to find the most relevant information for online users. By analyzing the historical selection records of users, recommender system predicts the most likely future links in the user-item network and accordingly constructs a personalized recommendation list for each user. So far, the recommendation process is mostly investigated in static user-item networks. In this paper, we propose a model which allows us to examine the performance of the state-of-the-art recommendation algorithms in evolving networks. We find that the recommendation accuracy in general decreases with time if the evolution of the online network fully depends on the recommendation. Interestingly, some randomness in users' choice can significantly improve the long-term accuracy of the recommendation algorithm. When a hybrid recommendation algorithm is applied, we find that the optimal parameter gradually shifts towards the diversity-favoring recommendation algorithm, indicating that recommendation diversity is essential to keep a high long-term recommendation accuracy. Finally, we confirm our conclusions by studying the recommendation on networks with the real evolution data.

  19. Identifying Gatekeepers in Online Learning Networks

    Science.gov (United States)

    Gursakal, Necmi; Bozkurt, Aras

    2017-01-01

    The rise of the networked society has not only changed our perceptions but also the definitions, roles, processes and dynamics of online learning networks. From offline to online worlds, networks are everywhere and gatekeepers are an important entity in these networks. In this context, the purpose of this paper is to explore gatekeeping and…

  20. The Structure of Online Consumer Communication Networks

    NARCIS (Netherlands)

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

    2006-01-01

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

  1. Relationships of individuals in online social networks

    OpenAIRE

    Jānis Buholcs

    2013-01-01

    Relationships of individuals in online social networks Doctoral thesis abstract In the present doctoral thesis, I analyze interactions by individuals that take place in online social networking sites and evaluate them against users’ offline contacts. The theoretical framework is built upon social capital theory, Erving Goffman’s dramaturgical approach, Anthony Giddens’ concept of ‘pure relationships’, and accounts of online communities. Empirical data were gathered through o...

  2. The Deep Structure of Organizational Online Networking

    DEFF Research Database (Denmark)

    Trier, Matthias; Richter, Alexander

    2015-01-01

    While research on organizational online networking recently increased significantly, most studies adopt quantitative research designs with a focus on the consequences of social network configurations. Very limited attention is paid to comprehensive theoretical conceptions of the complex phenomenon...... of organizational online networking. We address this gap by adopting a theoretical framework of the deep structure of organizational online networking with a focus on their emerging meaning for the employees. We apply and assess the framework in a qualitative case study of a large-scale implementation...... of a corporate social network site (SNS) in a global organization. We reveal organizational online networking as a multi-dimensional phenomenon with multiplex relationships that are unbalanced, primarily consist of weak ties and are subject to temporal change. Further, we identify discourse drivers...

  3. Online networks and subjective well-being

    OpenAIRE

    Sabatini, Fabio; Sarracino, Francesco

    2014-01-01

    Does Facebook make people lonely and unhappy? Empirical studies have produced conflicting results about the effect of social network- ing sites (SNS) use on individual welfare. We use a representative sample of the Italian population to investigate how actual and virtual networks of social relationships influence subjective well-being (SWB). We find a significantly negative correlation between online networking and self-reported happiness. We address endogeneity in online net- working by expl...

  4. Online Social Networking: Usage in Adolescents

    Science.gov (United States)

    Raju, Nevil Johnson; Valsaraj, Blessy Prabha; Noronha, Judith

    2015-01-01

    Online social networking (OSN) has played a significant role on the relationship among college students. It is becoming a popular medium for socializing online and tools to facilitate friendship. Young adults and adolescents are the most prolific users of OSN sites. The frequent use of OSN sites results in addiction toward these sites and…

  5. Online Social Networking: A Primer for Radiology

    OpenAIRE

    Prasanna, Prasanth M.; Seagull, F. Jacob; Nagy, Paul

    2011-01-01

    Online social networking is an immature, but rapidly evolving industry of web-based technologies that allow individuals to develop online relationships. News stories populate the headlines about various websites which can facilitate patient and doctor interaction. There remain questions about protecting patient confidentiality and defining etiquette in order to preserve the doctor/patient relationship and protect physicians. How much social networking-based communication or other forms of E-c...

  6. Evolution of a large online social network

    International Nuclear Information System (INIS)

    Hu Haibo; Wang Xiaofan

    2009-01-01

    Although recently there are extensive research on the collaborative networks and online communities, there is very limited knowledge about the actual evolution of the online social networks (OSN). In the Letter, we study the structural evolution of a large online virtual community. We find that the scale growth of the OSN shows non-trivial S shape which may provide a proper exemplification for Bass diffusion model. We reveal that the evolutions of many network properties, such as density, clustering, heterogeneity and modularity, show non-monotone feature, and shrink phenomenon occurs for the path length and diameter of the network. Furthermore, the OSN underwent a transition from degree assortativity characteristic of collaborative networks to degree disassortativity characteristic of many OSNs. Our study has revealed the evolutionary pattern of interpersonal interactions in a specific population and provided a valuable platform for theoretical modeling and further analysis

  7. Online professional networks for physicians: risk management.

    Science.gov (United States)

    Hyman, Jon L; Luks, Howard J; Sechrest, Randale

    2012-05-01

    The rapidly developing array of online physician-only communities represents a potential extraordinary advance in the availability of educational and informational resources to physicians. These online communities provide physicians with a new range of controls over the information they process, but use of this social media technology carries some risk. The purpose of this review was to help physicians manage the risks of online professional networking and discuss the potential benefits that may come with such networks. This article explores the risks and benefits of physicians engaging in online professional networking with peers and provides suggestions on risk management. Through an Internet search and literature review, we scrutinized available case law, federal regulatory code, and guidelines of conduct from professional organizations and consultants. We reviewed the OrthoMind.com site as a case example because it is currently the only online social network exclusively for orthopaedic surgeons. Existing case law suggests potential liability for orthopaedic surgeons who engage with patients on openly accessible social network platforms. Current society guidelines in both the United States and Britain provide sensible rules that may mitigate such risks. However, the overall lack of a strong body of legal opinions, government regulations as well as practical experience for most surgeons limit the suitability of such platforms. Closed platforms that are restricted to validated orthopaedic surgeons may limit these downside risks and hence allow surgeons to collaborate with one another both as clinicians and practice owners. Educating surgeons about the pros and cons of participating in these networking platforms is helping them more astutely manage risks and optimize benefits. This evolving online environment of professional interaction is one of few precedents, but the application of risk management strategies that physicians use in daily practice carries over

  8. How do online social networks grow?

    Science.gov (United States)

    Zhu, Konglin; Li, Wenzhong; Fu, Xiaoming; Nagler, Jan

    2014-01-01

    Online social networks such as Facebook, Twitter and Gowalla allow people to communicate and interact across borders. In past years online social networks have become increasingly important for studying the behavior of individuals, group formation, and the emergence of online societies. Here we focus on the characterization of the average growth of online social networks and try to understand which are possible processes behind seemingly long-range temporal correlated collective behavior. In agreement with recent findings, but in contrast to Gibrat's law of proportionate growth, we find scaling in the average growth rate and its standard deviation. In contrast, Renren and Twitter deviate, however, in certain important aspects significantly from those found in many social and economic systems. Whereas independent methods suggest no significance for temporally long-range correlated behavior for Renren and Twitter, a scaling analysis of the standard deviation does suggest long-range temporal correlated growth in Gowalla. However, we demonstrate that seemingly long-range temporal correlations in the growth of online social networks, such as in Gowalla, can be explained by a decomposition into temporally and spatially independent growth processes with a large variety of entry rates. Our analysis thus suggests that temporally or spatially correlated behavior does not play a major role in the growth of online social networks.

  9. Intercultural Communication in Online Social Networking Discourse

    Science.gov (United States)

    Chen, Hsin-I

    2017-01-01

    This article presents a case study that examines how an online social networking community is constituted through intercultural discourse on the part of one learner sojourning in the US. Using Byram's model of intercultural communicative competence, this study examines the learner's naturalistic communication in a social networking site (SNS). The…

  10. Content Propagation in Online Social Networks

    NARCIS (Netherlands)

    Blenn, N.

    2014-01-01

    This thesis presents methods and techniques to analyze content propagation within online social networks (OSNs) using a graph theoretical approach. Important factors and different techniques to analyze and describe content propagation, starting from the smallest entity in a network, representing a

  11. Information diffusion in structured online social networks

    Science.gov (United States)

    Li, Pei; Zhang, Yini; Qiao, Fengcai; Wang, Hui

    2015-05-01

    Nowadays, due to the word-of-mouth effect, online social networks have been considered to be efficient approaches to conduct viral marketing, which makes it of great importance to understand the diffusion dynamics in online social networks. However, most research on diffusion dynamics in epidemiology and existing social networks cannot be applied directly to characterize online social networks. In this paper, we propose models to characterize the information diffusion in structured online social networks with push-based forwarding mechanism. We introduce the term user influence to characterize the average number of times that messages are browsed which is incurred by a given type user generating a message, and study the diffusion threshold, above which the user influence of generating a message will approach infinity. We conduct simulations and provide the simulation results, which are consistent with the theoretical analysis results perfectly. These results are of use in understanding the diffusion dynamics in online social networks and also critical for advertisers in viral marketing who want to estimate the user influence before posting an advertisement.

  12. Online social network data as sociometric markers.

    Science.gov (United States)

    Binder, Jens F; Buglass, Sarah L; Betts, Lucy R; Underwood, Jean D M

    2017-10-01

    Data from online social networks carry enormous potential for psychological research, yet their use and the ethical implications thereof are currently hotly debated. The present work aims to outline in detail the unique information richness of this data type and, in doing so, to support researchers when deciding on ethically appropriate ways of collecting, storing, publishing, and sharing data from online sources. Focusing on the very nature of social networks, their structural characteristics, and depth of information, we provide a detailed and accessible account of the challenges associated with data management and data storage. In particular, the general nonanonymity of network data sets is discussed, and an approach is developed to quantify the level of uniqueness that a particular online network bestows upon the individual maintaining it. Using graph enumeration techniques, we show that comparatively sparse information on a network is suitable as a sociometric marker that allows for the identification of an individual from the global population of online users. The impossibility of anonymizing specific types of network data carries implications for ethical guidelines and research practice. At the same time, network uniqueness opens up opportunities for novel research in psychology. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  13. Benford's Law Applies to Online Social Networks.

    Directory of Open Access Journals (Sweden)

    Jennifer Golbeck

    Full Text Available Benford's Law states that, in naturally occurring systems, the frequency of numbers' first digits is not evenly distributed. Numbers beginning with a 1 occur roughly 30% of the time, and are six times more common than numbers beginning with a 9. We show that Benford's Law applies to social and behavioral features of users in online social networks. Using social data from five major social networks (Facebook, Twitter, Google Plus, Pinterest, and LiveJournal, we show that the distribution of first significant digits of friend and follower counts for users in these systems follow Benford's Law. The same is true for the number of posts users make. We extend this to egocentric networks, showing that friend counts among the people in an individual's social network also follows the expected distribution. We discuss how this can be used to detect suspicious or fraudulent activity online and to validate datasets.

  14. Finding relevant people in online social networks

    OpenAIRE

    Sáez-Trumper, Diego

    2013-01-01

    The objective of this thesis is to develop novel techniques to find relevant people in Online Social Networks (OSN). To that end, we consider different notions of relevance, taking the point of view of the OSN providers (like Facebook) and advertisers, as well as considering the people who are trying to push new ideas and topics on the network. We go beyond people's popularity, showing that the users with a lot of followers are not necessarily the most relevant. Specifically, we develop three...

  15. Structural Changes in Online Discussion Networks

    DEFF Research Database (Denmark)

    Yang, Yang; Medaglia, Rony

    2014-01-01

    Social networking platforms in China provide a hugely interesting and relevant source for understanding dynamics of online discussions in a unique socio-cultural and institutional environment. This paper investigates the evolution of patterns of similar-minded and different-minded interactions over...

  16. Community Structure in Online Collegiate Social Networks

    Science.gov (United States)

    Traud, Amanda; Kelsic, Eric; Mucha, Peter; Porter, Mason

    2009-03-01

    Online social networking sites have become increasingly popular with college students. The networks we studied are defined through ``friendships'' indicated by Facebook users from UNC, Oklahoma, Caltech, Georgetown, and Princeton. We apply the tools of network science to study the Facebook networks from these five different universities at a single point in time. We investigate each single-institution network's community structure, which we obtain through partitioning the graph using an eigenvector method. We use both graphical and quantitative tools, including pair-counting methods, which we interpret through statistical analysis and permutation tests to measure the correlations between the network communities and a set of characteristics given by each user (residence, class year, major, and high school). We also analyze the single gender subsets of these networks, and the impact of missing demographical data. Our study allows us to compare the online social networks for the five schools as well as infer differences in offline social interactions. At the schools studied, we were able to define which characteristics of the Facebook users correlate best with friendships.

  17. A framework for online social networking features

    Directory of Open Access Journals (Sweden)

    Mohsen Shafiei Nikabadi

    2014-06-01

    Full Text Available Social networks form a basis for maintaining social contacts, finding users with common interests, creating local content and sharing information. Recently networks have created a fundamental framework for analyzing and modeling the complex systems. Users' behavior studies and evaluates the system performance and leads to better planning and implementation of advertising policies on the web sites. Therefore, this study offers a framework for online social networks' characteristics. In terms of objective, this survey is practical descriptive. Sampling has been done among 384 of graduate students who have good experiences of membership in online social network. Confirmatory factor analysis is used to evaluate the validity of variables in research model. Characteristics of online social networks are defined based on six components and framework's indexes are analyzed through factor analysis. The reliability is calculated separately for each dimension and since they are all above 0.7, the reliability of the study can be confirmed. According to our research results, in terms of size, the number of people who apply for membership in various online social networking is an important index. In terms of individual preference to connect with, people who are relative play essential role in social network development. In terms of homogeneity variable, the number of people who visit their friends’ pages is important for measuring frequency variable. In terms of frequency, the use of entertainment and recreation services is more important index. In terms of proximity, being in the same city is a more important index and index of creating a sense of belonging and confidence is more important for measuring reciprocity variable.

  18. Link prediction in multiplex online social networks

    Science.gov (United States)

    Jalili, Mahdi; Orouskhani, Yasin; Asgari, Milad; Alipourfard, Nazanin; Perc, Matjaž

    2017-02-01

    Online social networks play a major role in modern societies, and they have shaped the way social relationships evolve. Link prediction in social networks has many potential applications such as recommending new items to users, friendship suggestion and discovering spurious connections. Many real social networks evolve the connections in multiple layers (e.g. multiple social networking platforms). In this article, we study the link prediction problem in multiplex networks. As an example, we consider a multiplex network of Twitter (as a microblogging service) and Foursquare (as a location-based social network). We consider social networks of the same users in these two platforms and develop a meta-path-based algorithm for predicting the links. The connectivity information of the two layers is used to predict the links in Foursquare network. Three classical classifiers (naive Bayes, support vector machines (SVM) and K-nearest neighbour) are used for the classification task. Although the networks are not highly correlated in the layers, our experiments show that including the cross-layer information significantly improves the prediction performance. The SVM classifier results in the best performance with an average accuracy of 89%.

  19. Link prediction in multiplex online social networks.

    Science.gov (United States)

    Jalili, Mahdi; Orouskhani, Yasin; Asgari, Milad; Alipourfard, Nazanin; Perc, Matjaž

    2017-02-01

    Online social networks play a major role in modern societies, and they have shaped the way social relationships evolve. Link prediction in social networks has many potential applications such as recommending new items to users, friendship suggestion and discovering spurious connections. Many real social networks evolve the connections in multiple layers (e.g. multiple social networking platforms). In this article, we study the link prediction problem in multiplex networks. As an example, we consider a multiplex network of Twitter (as a microblogging service) and Foursquare (as a location-based social network). We consider social networks of the same users in these two platforms and develop a meta-path-based algorithm for predicting the links. The connectivity information of the two layers is used to predict the links in Foursquare network. Three classical classifiers (naive Bayes, support vector machines (SVM) and K-nearest neighbour) are used for the classification task. Although the networks are not highly correlated in the layers, our experiments show that including the cross-layer information significantly improves the prediction performance. The SVM classifier results in the best performance with an average accuracy of 89%.

  20. Security and trust in online social networks

    CERN Document Server

    Carminati, Barbara; Viviani, Marco; Viviani, Marco; Carminati, Barbara

    2013-01-01

    The enormous success and diffusion that online social networks (OSNs) are encountering nowadays is vastly apparent. Users' social interactions now occur using online social media as communication channels; personal information and activities are easily exchanged both for recreational and business purposes in order to obtain social or economic advantages. In this scenario, OSNs are considered critical applications with respect to the security of users and their resources, for their characteristics alone: the large amount of personal information they manage, big economic upturn connected to thei

  1. Online social networking: a primer for radiology.

    Science.gov (United States)

    Prasanna, Prasanth M; Seagull, F Jacob; Nagy, Paul

    2011-10-01

    Online social networking is an immature, but rapidly evolving industry of web-based technologies that allow individuals to develop online relationships. News stories populate the headlines about various websites which can facilitate patient and doctor interaction. There remain questions about protecting patient confidentiality and defining etiquette in order to preserve the doctor/patient relationship and protect physicians. How much social networking-based communication or other forms of E-communication is effective? What are the potential benefits and pitfalls of this form of communication? Physicians are exploring how social networking might provide a forum for interacting with their patients, and advance collaborative patient care. Several organizations and institutions have set forth policies to address these questions and more. Though still in its infancy, this form of media has the power to revolutionize the way physicians interact with their patients and fellow health care workers. In the end, physicians must ask what value is added by engaging patients or other health care providers in a social networking format. Social networks may flourish in health care as a means of distributing information to patients or serve mainly as support groups among patients. Physicians must tread a narrow path to bring value to interactions in these networks while limiting their exposure to unwanted liability.

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

    Directory of Open Access Journals (Sweden)

    Yang SONG

    2015-01-01

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

  3. Discrete Opinion Dynamics on Online Social Networks

    Science.gov (United States)

    Hu, Yan-Li; Bai, Liang; Zhang, Wei-Ming

    2013-01-01

    This paper focuses on the dynamics of binary opinions {+1, -1} on online social networks consisting of heterogeneous actors. In our model, actors update their opinions under the interplay of social influence and self- affirmation, which leads to rich dynamical behaviors on online social networks. We find that the opinion leading to the consensus features an advantage of the initially weighted fraction based on actors' strength over the other, instead of the population. For the role of specific actors, the consensus converges towards the opinion that a small fraction of high-strength actors hold, and individual diversity of self-affirmation slows down the ordering process of consensus. These indicate that high-strength actors play an essential role in opinion formation with strong social influence as well as high persistence. Further investigations show that the initial fraction of high-strength actors to dominate the evolution depends on the heterogeneity of the strength distribution, and less high-strength actors are needed in the case of a smaller exponent of power-law distribution of actors' strength. Our study provides deep insights into the role of social influence and self-affirmation on opinion formation on online social networks.

  4. Discrete Opinion Dynamics on Online Social Networks

    International Nuclear Information System (INIS)

    Hu Yan-Li; Bai Liang; Zhang Wei-Ming

    2013-01-01

    This paper focuses on the dynamics of binary opinions {+1, −1} on online social networks consisting of heterogeneous actors. In our model, actors update their opinions under the interplay of social influence and self- affirmation, which leads to rich dynamical behaviors on online social networks. We find that the opinion leading to the consensus features an advantage of the initially weighted fraction based on actors' strength over the other, instead of the population. For the role of specific actors, the consensus converges towards the opinion that a small fraction of high-strength actors hold, and individual diversity of self-affirmation slows down the ordering process of consensus. These indicate that high-strength actors play an essential role in opinion formation with strong social influence as well as high persistence. Further investigations show that the initial fraction of high-strength actors to dominate the evolution depends on the heterogeneity of the strength distribution, and less high-strength actors are needed in the case of a smaller exponent of power-law distribution of actors' strength. Our study provides deep insights into the role of social influence and self-affirmation on opinion formation on online social networks. (general)

  5. Inferring Social Relations from Online and Communication Networks

    OpenAIRE

    Nasim, Mehwish

    2016-01-01

    In this work analyzed the interplay between social relations in the form of friendship ties, attributes and interaction in online social networks. In this context we analyzed composition of social circles in online social networks and showed that social circles are homophilious with respect to at least one node attribute. We showed that using the right combination of network and interaction features, links can be inferred in online covert networks. We also analyzed longitudinal dyadic interac...

  6. Online social networking and mental health.

    Science.gov (United States)

    Pantic, Igor

    2014-10-01

    During the past decade, online social networking has caused profound changes in the way people communicate and interact. It is unclear, however, whether some of these changes may affect certain normal aspects of human behavior and cause psychiatric disorders. Several studies have indicated that the prolonged use of social networking sites (SNS), such as Facebook, may be related to signs and symptoms of depression. In addition, some authors have indicated that certain SNS activities might be associated with low self-esteem, especially in children and adolescents. Other studies have presented opposite results in terms of positive impact of social networking on self-esteem. The relationship between SNS use and mental problems to this day remains controversial, and research on this issue is faced with numerous challenges. This concise review focuses on the recent findings regarding the suggested connection between SNS and mental health issues such as depressive symptoms, changes in self-esteem, and Internet addiction.

  7. Online Networks and the Diffusion of Protests

    Science.gov (United States)

    Moreno, Yamir

    2013-03-01

    Undoubtedly, online social networks have an enormous impact on opinions and cultural trends. Also, these platforms have revealed as a fundamental organizing mechanism in country-wide social movements. Recent events in the Middle East and North Africa (the wave of protests in the Arab world), across Europe (in the form of anti-cuts demonstrations or riots) and United States (the OWS movement) have generated much discussion on how digital media is connected to the diffusion of protests. In this talk, we investigate the mechanisms driving the emergence, development and stabilization of unrest movements in Spain and the USA by analyzing data from Twitter. Messages related to the protests are analyzed at both static and dynamic levels. We show that the online trace of the protests provides a unique opportunity to tackle central issues like recruitment patterns, information cascades and their spatiotemporal dynamics. Our findings shed light on the connection between online networks and social movements, and offer an empirical test to elusive sociological questions about collective action.

  8. 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.

  9. Anatomy of an online misinformation network.

    Science.gov (United States)

    Shao, Chengcheng; Hui, Pik-Mai; Wang, Lei; Jiang, Xinwen; Flammini, Alessandro; Menczer, Filippo; Ciampaglia, Giovanni Luca

    2018-01-01

    Massive amounts of fake news and conspiratorial content have spread over social media before and after the 2016 US Presidential Elections despite intense fact-checking efforts. How do the spread of misinformation and fact-checking compete? What are the structural and dynamic characteristics of the core of the misinformation diffusion network, and who are its main purveyors? How to reduce the overall amount of misinformation? To explore these questions we built Hoaxy, an open platform that enables large-scale, systematic studies of how misinformation and fact-checking spread and compete on Twitter. Hoaxy captures public tweets that include links to articles from low-credibility and fact-checking sources. We perform k-core decomposition on a diffusion network obtained from two million retweets produced by several hundred thousand accounts over the six months before the election. As we move from the periphery to the core of the network, fact-checking nearly disappears, while social bots proliferate. The number of users in the main core reaches equilibrium around the time of the election, with limited churn and increasingly dense connections. We conclude by quantifying how effectively the network can be disrupted by penalizing the most central nodes. These findings provide a first look at the anatomy of a massive online misinformation diffusion network.

  10. Data Quality in Online Health Social Networks for Chronic Diseases

    Science.gov (United States)

    Venkatesan, Srikanth

    2017-01-01

    Can medical advice from other participants in online health social networks impact patient safety? What can we do alleviate this problem? How does the accuracy of information on such networks affect the patients?. There has been a significant increase , in recent years, in the use of online health social network sites as more patients seek to…

  11. Stochastic Online Learning in Dynamic Networks under Unknown Models

    Science.gov (United States)

    2016-08-02

    Stochastic Online Learning in Dynamic Networks under Unknown Models This research aims to develop fundamental theories and practical algorithms for...12211 Research Triangle Park, NC 27709-2211 Online learning , multi-armed bandit, dynamic networks REPORT DOCUMENTATION PAGE 11. SPONSOR/MONITOR’S... Online Learning in Dynamic Networks under Unknown Models Report Title This research aims to develop fundamental theories and practical algorithms for

  12. Optimizing online social networks for information propagation.

    Directory of Open Access Journals (Sweden)

    Duan-Bing Chen

    Full Text Available Online users nowadays are facing serious information overload problem. In recent years, recommender systems have been widely studied to help people find relevant information. Adaptive social recommendation is one of these systems in which the connections in the online social networks are optimized for the information propagation so that users can receive interesting news or stories from their leaders. Validation of such adaptive social recommendation methods in the literature assumes uniform distribution of users' activity frequency. In this paper, our empirical analysis shows that the distribution of online users' activity is actually heterogenous. Accordingly, we propose a more realistic multi-agent model in which users' activity frequency are drawn from a power-law distribution. We find that previous social recommendation methods lead to serious delay of information propagation since many users are connected to inactive leaders. To solve this problem, we design a new similarity measure which takes into account users' activity frequencies. With this similarity measure, the average delay is significantly shortened and the recommendation accuracy is largely improved.

  13. Optimizing online social networks for information propagation.

    Science.gov (United States)

    Chen, Duan-Bing; Wang, Guan-Nan; Zeng, An; Fu, Yan; Zhang, Yi-Cheng

    2014-01-01

    Online users nowadays are facing serious information overload problem. In recent years, recommender systems have been widely studied to help people find relevant information. Adaptive social recommendation is one of these systems in which the connections in the online social networks are optimized for the information propagation so that users can receive interesting news or stories from their leaders. Validation of such adaptive social recommendation methods in the literature assumes uniform distribution of users' activity frequency. In this paper, our empirical analysis shows that the distribution of online users' activity is actually heterogenous. Accordingly, we propose a more realistic multi-agent model in which users' activity frequency are drawn from a power-law distribution. We find that previous social recommendation methods lead to serious delay of information propagation since many users are connected to inactive leaders. To solve this problem, we design a new similarity measure which takes into account users' activity frequencies. With this similarity measure, the average delay is significantly shortened and the recommendation accuracy is largely improved.

  14. Online social networking in people with psychosis: A systematic review.

    Science.gov (United States)

    Highton-Williamson, Elizabeth; Priebe, Stefan; Giacco, Domenico

    2015-02-01

    Online social networking might facilitate the establishment of social contacts for people with psychosis, who are often socially isolated by the symptoms and consequences of their disorder. We carried out a systematic review exploring available evidence on the use of online social networking in people with psychosis. The review was conducted following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Included studies examined the use of the online social networking by people with an a priori diagnosis of psychosis (inclusive of bipolar disorder). Data from included studies were extracted and narratively synthesised. A total of 11 studies, published between 2005 and 2013, reported data on online social networking in people with psychosis. People with psychosis seem to spend more time in chat rooms or playing online games than control groups. The use of other online tools, such as Facebook or communication through e-mail, is lower or the same than controls. Online social networking was used by patients with psychosis for establishing new relationships, maintaining relationships/reconnecting with people and online peer support. Online social networking, in the form of forums or online chats, could play a role in strategies aimed at enhancing social networks and reduce the risk of isolation in this population. © The Author(s) 2014.

  15. Social networking in online support groups for health: how online social networking benefits patients.

    Science.gov (United States)

    Chung, Jae Eun

    2014-01-01

    An increasing number of online support groups (OSGs) have embraced the features of social networking. So far, little is known about how patients use and benefit from these features. By implementing the uses-and-gratifications framework, the author conducted an online survey with current users of OSGs to examine associations among motivation, use of specific features of OSG, and support outcomes. Findings suggest that OSG users make selective use of varied features depending on their needs, and that perceptions of receiving emotional and informational support are associated more with the use of some features than others. For example, those with strong motivation for social interaction use diverse features of OSG and make one-to-one connections with other users by friending. In contrast, those with strong motivation for information seeking limit their use primarily to discussion boards. Results also show that online social networking features, such as friending and sharing of personal stories on blogs, are helpful in satisfying the need for emotional support. The present study sheds light on online social networking features in the context of health-related OSGs and provides practical lessons on how to improve the capacity of OSGs to serve the needs of their users.

  16. Measuring structural similarity in large online networks.

    Science.gov (United States)

    Shi, Yongren; Macy, Michael

    2016-09-01

    Structural similarity based on bipartite graphs can be used to detect meaningful communities, but the networks have been tiny compared to massive online networks. Scalability is important in applications involving tens of millions of individuals with highly skewed degree distributions. Simulation analysis holding underlying similarity constant shows that two widely used measures - Jaccard index and cosine similarity - are biased by the distribution of out-degree in web-scale networks. However, an alternative measure, the Standardized Co-incident Ratio (SCR), is unbiased. We apply SCR to members of Congress, musical artists, and professional sports teams to show how massive co-following on Twitter can be used to map meaningful affiliations among cultural entities, even in the absence of direct connections to one another. Our results show how structural similarity can be used to map cultural alignments and demonstrate the potential usefulness of social media data in the study of culture, politics, and organizations across the social and behavioral sciences. Copyright © 2016 Elsevier Inc. All rights reserved.

  17. CALIBRATION OF ONLINE ANALYZERS USING NEURAL NETWORKS

    Energy Technology Data Exchange (ETDEWEB)

    Rajive Ganguli; Daniel E. Walsh; Shaohai Yu

    2003-12-05

    Neural networks were used to calibrate an online ash analyzer at the Usibelli Coal Mine, Healy, Alaska, by relating the Americium and Cesium counts to the ash content. A total of 104 samples were collected from the mine, with 47 being from screened coal, and the rest being from unscreened coal. Each sample corresponded to 20 seconds of coal on the running conveyor belt. Neural network modeling used the quick stop training procedure. Therefore, the samples were split into training, calibration and prediction subsets. Special techniques, using genetic algorithms, were developed to representatively split the sample into the three subsets. Two separate approaches were tried. In one approach, the screened and unscreened coal was modeled separately. In another, a single model was developed for the entire dataset. No advantage was seen from modeling the two subsets separately. The neural network method performed very well on average but not individually, i.e. though each prediction was unreliable, the average of a few predictions was close to the true average. Thus, the method demonstrated that the analyzers were accurate at 2-3 minutes intervals (average of 6-9 samples), but not at 20 seconds (each prediction).

  18. Modeling online social networks based on preferential linking

    International Nuclear Information System (INIS)

    Hu Hai-Bo; Chen Jun; Guo Jin-Li

    2012-01-01

    We study the phenomena of preferential linking in a large-scale evolving online social network and find that the linear preference holds for preferential creation, preferential acceptance, and preferential attachment. Based on the linear preference, we propose an analyzable model, which illustrates the mechanism of network growth and reproduces the process of network evolution. Our simulations demonstrate that the degree distribution of the network produced by the model is in good agreement with that of the real network. This work provides a possible bridge between the micro-mechanisms of network growth and the macrostructures of online social networks

  19. Pharmaceutical drugs chatter on Online Social Networks.

    Science.gov (United States)

    Wiley, Matthew T; Jin, Canghong; Hristidis, Vagelis; Esterling, Kevin M

    2014-06-01

    The ubiquity of Online Social Networks (OSNs) is creating new sources for healthcare information, particularly in the context of pharmaceutical drugs. We aimed to examine the impact of a given OSN's characteristics on the content of pharmaceutical drug discussions from that OSN. We compared the effect of four distinguishing characteristics from ten different OSNs on the content of their pharmaceutical drug discussions: (1) General versus Health OSN; (2) OSN moderation; (3) OSN registration requirements; and (4) OSNs with a question and answer format. The effects of these characteristics were measured both quantitatively and qualitatively. Our results show that an OSN's characteristics indeed affect the content of its discussions. Based on their information needs, healthcare providers may use our findings to pick the right OSNs or to advise patients regarding their needs. Our results may also guide the creation of new and more effective domain-specific health OSNs. Further, future researchers of online healthcare content in OSNs may find our results informative while choosing OSNs as data sources. We reported several findings about the impact of OSN characteristics on the content of pharmaceutical drug discussion, and synthesized these findings into actionable items for both healthcare providers and future researchers of healthcare discussions on OSNs. Future research on the impact of OSN characteristics could include user demographics, quality and safety of information, and efficacy of OSN usage. Copyright © 2014 Elsevier Inc. All rights reserved.

  20. Online communities: Challenges and opportunities for social network research

    NARCIS (Netherlands)

    Groenewegen, P.; Moser, C.; Brass, D.; Labianca, G.; Mehra, A.; Halgin, D; Borgatti, S

    2014-01-01

    Online communities form a challenging and still-evolving field for social network research. We highlight two themes that are at the core of social network literature: formative processes and structures, and discuss how these might be relevant in the context of online communities. Processes of tie

  1. Online Social Networks - Opportunities for Empowering Cancer Patients.

    Science.gov (United States)

    Mohammadzadeh, Zeinab; Davoodi, Somayeh; Ghazisaeidi, Marjan

    2016-01-01

    Online social network technologies have become important to health and apply in most health care areas. Particularly in cancer care, because it is a disease which involves many social aspects, online social networks can be very useful. Use of online social networks provides a suitable platform for cancer patients and families to present and share information about their medical conditions, address their educational needs, support decision making, and help to coping with their disease and improve their own outcomes. Like any other new technologies, online social networks, along with many benefits, have some negative effects such as violation of privacy and publication of incorrect information. However, if these effects are managed properly, they can empower patients to manage cancer through changing behavioral patterns and enhancing the quality of cancer patients lives This paper explains some application of online social networks in the cancer patient care process. It also covers advantages and disadvantages of related technologies.

  2. A last updating evolution model for online social networks

    Science.gov (United States)

    Bu, Zhan; Xia, Zhengyou; Wang, Jiandong; Zhang, Chengcui

    2013-05-01

    As information technology has advanced, people are turning to electronic media more frequently for communication, and social relationships are increasingly found on online channels. However, there is very limited knowledge about the actual evolution of the online social networks. In this paper, we propose and study a novel evolution network model with the new concept of “last updating time”, which exists in many real-life online social networks. The last updating evolution network model can maintain the robustness of scale-free networks and can improve the network reliance against intentional attacks. What is more, we also found that it has the “small-world effect”, which is the inherent property of most social networks. Simulation experiment based on this model show that the results and the real-life data are consistent, which means that our model is valid.

  3. Social Network Influence on Online Behavioral Choices: Exploring Group Formation on Social Network Sites

    OpenAIRE

    Kwon, KH; Stefanone, MA; Barnett, GA

    2014-01-01

    Social media communication is characterized by reduced anonymity and off-to-online social interactions. These characteristics require scholars to revisit social influence mechanisms online. The current study builds on social influence literature to explore social network and gender effects on online behavior. Findings from a quasi-experiment suggest that both network-related variables and gender are significantly associated with online behavior. Perceived social environment, measured by perso...

  4. VIOLIN: vaccine investigation and online information network.

    Science.gov (United States)

    Xiang, Zuoshuang; Todd, Thomas; Ku, Kim P; Kovacic, Bethany L; Larson, Charles B; Chen, Fang; Hodges, Andrew P; Tian, Yuying; Olenzek, Elizabeth A; Zhao, Boyang; Colby, Lesley A; Rush, Howard G; Gilsdorf, Janet R; Jourdian, George W; He, Yongqun

    2008-01-01

    Vaccines are among the most efficacious and cost-effective tools for reducing morbidity and mortality caused by infectious diseases. The vaccine investigation and online information network (VIOLIN) is a web-based central resource, allowing easy curation, comparison and analysis of vaccine-related research data across various human pathogens (e.g. Haemophilus influenzae, human immunodeficiency virus (HIV) and Plasmodium falciparum) of medical importance and across humans, other natural hosts and laboratory animals. Vaccine-related peer-reviewed literature data have been downloaded into the database from PubMed and are searchable through various literature search programs. Vaccine data are also annotated, edited and submitted to the database through a web-based interactive system that integrates efficient computational literature mining and accurate manual curation. Curated information includes general microbial pathogenesis and host protective immunity, vaccine preparation and characteristics, stimulated host responses after vaccination and protection efficacy after challenge. Vaccine-related pathogen and host genes are also annotated and available for searching through customized BLAST programs. All VIOLIN data are available for download in an eXtensible Markup Language (XML)-based data exchange format. VIOLIN is expected to become a centralized source of vaccine information and to provide investigators in basic and clinical sciences with curated data and bioinformatics tools for vaccine research and development. VIOLIN is publicly available at http://www.violinet.org.

  5. Academics’ online connections: Characterising the structure of personal networks on academic social networking sites and Twitter

    OpenAIRE

    Jordan, Katy

    2016-01-01

    Academic social networking sites (SNS), such as Academia.edu and ResearchGate, seek to bring the benefits of online social networking to academics' professional lives. Online academic social networking offers the potential to revolutionise academic publishing, foster novel collaborations, and empower academics to develop their professional identities online. However, the role that such sites play in relation to academic practice and other social media is not well understood at present.\\ud \\ud...

  6. An information spreading model based on online social networks

    Science.gov (United States)

    Wang, Tao; He, Juanjuan; Wang, Xiaoxia

    2018-01-01

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

  7. Emergence, evolution and scaling of online social networks.

    Directory of Open Access Journals (Sweden)

    Le-Zhi Wang

    Full Text Available Online social networks have become increasingly ubiquitous and understanding their structural, dynamical, and scaling properties not only is of fundamental interest but also has a broad range of applications. Such networks can be extremely dynamic, generated almost instantaneously by, for example, breaking-news items. We investigate a common class of online social networks, the user-user retweeting networks, by analyzing the empirical data collected from Sina Weibo (a massive twitter-like microblogging social network in China with respect to the topic of the 2011 Japan earthquake. We uncover a number of algebraic scaling relations governing the growth and structure of the network and develop a probabilistic model that captures the basic dynamical features of the system. The model is capable of reproducing all the empirical results. Our analysis not only reveals the basic mechanisms underlying the dynamics of the retweeting networks, but also provides general insights into the control of information spreading on such networks.

  8. Adolescents' and Emerging Adults' Social Networking Online: Homophily or Diversity?

    Science.gov (United States)

    Mazur, Elizabeth; Richards, Lacey

    2011-01-01

    More than half of all online American adolescents and emerging adults have created personal profiles for social networking on the Internet. Does homophily in their offline friendships extend online? Drawing mainly on research of face-to-face friendship, we collected data from the public spaces, called "walls," of 129 young Americans ages 16 to 19…

  9. Blessed Oblivion? Knowledge and Metacognitive Accuracy in Online Social Networks

    Science.gov (United States)

    Moll, Ricarda; Pieschl, Stephanie; Bromme, Rainer

    2015-01-01

    In order to reap the social gratifications of Online Social Networks (OSNs), users often disclose self-related information, making them potentially vulnerable to their online audiences. We give a brief overview of our theoretical ideas and empirical research about additional cognitive and metacognitive factors relevant for the perception of risk…

  10. Exploring Self-Disclosure in Online Social Networks

    Science.gov (United States)

    Velasco-Martin, Javier

    2013-01-01

    This project explores how experienced adult users of social media disclose personal information over online social networks (OSN). This work introduces a four-dimensional model to serve as a foundational framework for the study of online self-disclosure (OSD); these four dimensions are personal, social, technological and contextual, and support…

  11. Methods of Profile Cloning Detection in Online Social Networks

    Directory of Open Access Journals (Sweden)

    Zabielski Michał

    2016-01-01

    Full Text Available With the arrival of online social networks, the importance of privacy on the Internet has increased dramatically. Thus, it is important to develop mechanisms that will prevent our hidden personal data from unauthorized access and use. In this paper an attempt was made to present a concept of profile cloning detection in Online Social Networks (OSN using Graph and Networks Theory. By analysing structural similarity of network and value of attributes of user personal profile, we will be able to search for attackers which steal our identity.

  12. The effects of online social networks on tacit knowledge transmission

    Science.gov (United States)

    Zhu, Hong-Miao; Zhang, Sheng-Tai; Jin, Zhen

    2016-01-01

    Due to the popular use of online social networks in today's world, how to propagate employees' tacit knowledge via online social networks has attracted managers' attention, which is critical to enhance the competitiveness of firms. In this paper, we propose a tacit knowledge transmission model on networks with even mixing based on the propagation property of tacit knowledge and the application of online social networks. We consider two routes of transmission, which are contact through online social networks and face-to-face physical contact, and derive the threshold that governs whether or not a kind of tacit knowledge can be shared in an organization with few initial employees who have acquired it. The impact of the degree distribution of the users' contact network on the transmission is investigated analytically. Some numerical simulations are presented to support the theoretical results. We perform the sensitivity analysis of the threshold in terms of the propagation parameters and confirm that online social networks contribute significantly to enhancing the transmission of tacit knowledge among employees.

  13. Integrated Networks: National and International Online Experiences

    Directory of Open Access Journals (Sweden)

    Osvaldo Muniz-Solari

    2009-02-01

    Full Text Available There is an increasing impression among online geography educators that interaction can be developed based on specific teaching and learning methods. The authors developed a practical research study to investigate this issue. The study was based on advanced graduate courses in geography at Beijing Normal University and Texas State University. International interaction was complemented by online collaboration among the US local group. Both synchronous and asynchronous communication systems were used, which spanned two platforms. Results of this experience indicate that teaching and learning methods must be enhanced by a flexible online learning model and extensive organizational support in order to increase interaction and reach a certain level of cooperation.

  14. Blending Formal and Informal Learning Networks for Online Learning

    Science.gov (United States)

    Czerkawski, Betül C.

    2016-01-01

    With the emergence of social software and the advance of web-based technologies, online learning networks provide invaluable opportunities for learning, whether formal or informal. Unlike top-down, instructor-centered, and carefully planned formal learning settings, informal learning networks offer more bottom-up, student-centered participatory…

  15. How Will Online Affiliate Marketing Networks Impact Search Engine Rankings?

    NARCIS (Netherlands)

    D. Janssen (David); H.W.G.M. van Heck (Eric)

    2007-01-01

    textabstractIn online affiliate marketing networks advertising web sites offer their affiliates revenues based on provided web site traffic and associated leads and sales. Advertising web sites can have a network of thousands of affiliates providing them with web site traffic through hyperlinks on

  16. Studies on the population dynamics of a rumor-spreading model in online social networks

    Science.gov (United States)

    Dong, Suyalatu; Fan, Feng-Hua; Huang, Yong-Chang

    2018-02-01

    This paper sets up a rumor spreading model in online social networks based on the European fox rabies SIR model. The model considers the impact of changing number of online social network users, combines the transmission dynamics to set up a population dynamics of rumor spreading model in online social networks. Simulation is carried out on online social network, and results show that the new rumor spreading model is in accordance with the real propagation characteristics in online social networks.

  17. Characterizing interactions in online social networks during exceptional events

    Science.gov (United States)

    Omodei, Elisa; De Domenico, Manlio; Arenas, Alex

    2015-08-01

    Nowadays, millions of people interact on a daily basis on online social media like Facebook and Twitter, where they share and discuss information about a wide variety of topics. In this paper, we focus on a specific online social network, Twitter, and we analyze multiple datasets each one consisting of individuals' online activity before, during and after an exceptional event in terms of volume of the communications registered. We consider important events that occurred in different arenas that range from policy to culture or science. For each dataset, the users' online activities are modeled by a multilayer network in which each layer conveys a different kind of interaction, specifically: retweeting, mentioning and replying. This representation allows us to unveil that these distinct types of interaction produce networks with different statistical properties, in particular concerning the degree distribution and the clustering structure. These results suggests that models of online activity cannot discard the information carried by this multilayer representation of the system, and should account for the different processes generated by the different kinds of interactions. Secondly, our analysis unveils the presence of statistical regularities among the different events, suggesting that the non-trivial topological patterns that we observe may represent universal features of the social dynamics on online social networks during exceptional events.

  18. Student Support Networks in Online Doctoral Programs: Exploring Nested Communities

    Directory of Open Access Journals (Sweden)

    Sharla Berry

    2017-04-01

    Full Text Available Aim/Purpose: Enrollment in online doctoral programs has grown over the past decade. A sense of community, defined as feelings of closeness within a social group, is vital to retention, but few studies have explored how online doctoral students create community. Background: In this qualitative case study, I explore how students in one online doctoral program created a learning community. Methodology: Data for the study was drawn from 60 hours of video footage from six online courses, the message boards from the six courses, and twenty interviews with first and second-year students. Contribution: Findings from this study indicate that the structure of the social network in an online doctoral program is significantly different from the structure of learning communities in face-to-face programs. In the online program, the doctoral community was more insular, more peer-centered, and less reliant on faculty support than in in-person programs. Findings: Utilizing a nested communities theoretical framework, I identified four subgroups that informed online doctoral students’ sense of community: cohort, class groups, small peer groups, and study groups. Students interacted frequently with members of each of the aforementioned social groups and drew academic, social, and emotional support from their interactions. Recommendations for Practitioners: Data from this study suggests that online doctoral students are interested in making social and academic connections. Practitioners should leverage technology and on-campus supports to promote extracurricular interactions for online students. Recommendation for Researchers: Rather than focus on professional socialization, students in the online doctoral community were interested in providing social and academic support to peers. Researchers should consider how socialization in online doctoral programs differs from traditional, face-to-face programs. Impact on Society: As universities increase online offerings

  19. Competition between global and local online social networks

    Science.gov (United States)

    Kleineberg, Kaj-Kolja; Boguñá, Marián

    2016-04-01

    The overwhelming success of online social networks, the key actors in the Web 2.0 cosmos, has reshaped human interactions globally. To help understand the fundamental mechanisms which determine the fate of online social networks at the system level, we describe the digital world as a complex ecosystem of interacting networks. In this paper, we study the impact of heterogeneity in network fitnesses on the competition between an international network, such as Facebook, and local services. The higher fitness of international networks is induced by their ability to attract users from all over the world, which can then establish social interactions without the limitations of local networks. In other words, inter-country social ties lead to increased fitness of the international network. To study the competition between an international network and local ones, we construct a 1:1000 scale model of the digital world, consisting of the 80 countries with the most Internet users. Under certain conditions, this leads to the extinction of local networks; whereas under different conditions, local networks can persist and even dominate completely. In particular, our model suggests that, with the parameters that best reproduce the empirical overtake of Facebook, this overtake could have not taken place with a significant probability.

  20. 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...

  1. Incorporating profile information in community detection for online social networks

    Science.gov (United States)

    Fan, W.; Yeung, K. H.

    2014-07-01

    Community structure is an important feature in the study of complex networks. It is because nodes of the same community may have similar properties. In this paper we extend two popular community detection methods to partition online social networks. In our extended methods, the profile information of users is used for partitioning. We apply the extended methods in several sample networks of Facebook. Compared with the original methods, the community structures we obtain have higher modularity. Our results indicate that users' profile information is consistent with the community structure of their friendship network to some extent. To the best of our knowledge, this paper is the first to discuss how profile information can be used to improve community detection in online social networks.

  2. Exploration of Online Culture Through Network Analysis of Wikipedia.

    Science.gov (United States)

    Park, Sung Joo; Kim, Jong Woo; Lee, Hong Joo; Park, Hyunjung; Han, Deugcheon; Gloor, Peter

    2015-11-01

    Understanding online culture is becoming crucial in the global and connected world. Contrary to conventional attitudinal surveys used in cultural research, this study uses the approach of directly observing culture-specific behavior that emerges from online collaboration on the Internet. The editing data of Wikipedia were analyzed in 12 languages. Distinctive cultural dimensions were identified, including collectivism, extraversion, boldness, and egalitarianism. Using network analysis, the language-framed cultural factors were extracted as an emergent phenomenon in the virtual world.

  3. Entrepreneurial Idea Identification through Online Social Networks

    Science.gov (United States)

    Lang, Matthew C.

    2010-01-01

    The increasing use of social network websites may signal a change in the way the next generation of entrepreneurs identify entrepreneurial ideas. An important part of the entrepreneurship literature emphasizes how vital the use of social networks is to entrepreneurial idea identification, opportunity recognition, and ultimately new venture…

  4. Psychodynamic Factors Behind Online Social Networking and its Excessive Use.

    Science.gov (United States)

    Li, Thomas Cheuk Wing

    2016-03-01

    This article discusses the psychodynamic factors behind the popularity of one form of Internet activity, online social networking (SN). It views online SN as an extension of the social self, organized in a way that is more controllable than real life relating. The SN platforms reward its users with reassuring surfaces and novel self-object experiences while at the same time induces much anxiety. The addictive quality of online SN is understood in the context of collapse of dialectical space and the defensive use of this technology.

  5. Assembly effect of groups in online social networks

    Science.gov (United States)

    Fan, W.; Yeung, K. H.; Wong, K. Y.

    2013-03-01

    Due to the popularity and growth of online social networks, security in these networks becomes a critical problem. Previous works have proved that a virus can spread effectively in social networks. In this paper, groups in social networks are studied. We notice that groups on social network services sites can assemble people with similar characteristics, which may promote virus propagation in these networks. After our analysis, it is found that the use of groups can shorten the distance among users, and hence it would cause faster virus spread. We propose a virus propagation model and simulate it in a group network to show the assembly effect of groups. Our result shows that even with only one random attack, a virus can still spread rapidly, and the direct contact among group members is the reason for fast spreading.

  6. Interface Prostheses With Classifier-Feedback-Based User Training.

    Science.gov (United States)

    Fang, Yinfeng; Zhou, Dalin; Li, Kairu; Liu, Honghai

    2017-11-01

    It is evident that user training significantly affects performance of pattern-recognition-based myoelectric prosthetic device control. Despite plausible classification accuracy on offline datasets, online accuracy usually suffers from the changes in physiological conditions and electrode displacement. The user ability in generating consistent electromyographic (EMG) patterns can be enhanced via proper user training strategies in order to improve online performance. This study proposes a clustering-feedback strategy that provides real-time feedback to users by means of a visualized online EMG signal input as well as the centroids of the training samples, whose dimensionality is reduced to minimal number by dimension reduction. Clustering feedback provides a criterion that guides users to adjust motion gestures and muscle contraction forces intentionally. The experiment results have demonstrated that hand motion recognition accuracy increases steadily along the progress of the clustering-feedback-based user training, while conventional classifier-feedback methods, i.e., label feedback, hardly achieve any improvement. The result concludes that the use of proper classifier feedback can accelerate the process of user training, and implies prosperous future for the amputees with limited or no experience in pattern-recognition-based prosthetic device manipulation.It is evident that user training significantly affects performance of pattern-recognition-based myoelectric prosthetic device control. Despite plausible classification accuracy on offline datasets, online accuracy usually suffers from the changes in physiological conditions and electrode displacement. The user ability in generating consistent electromyographic (EMG) patterns can be enhanced via proper user training strategies in order to improve online performance. This study proposes a clustering-feedback strategy that provides real-time feedback to users by means of a visualized online EMG signal input as well

  7. How Will Online Affiliate Marketing Networks Impact Search Engine Rankings?

    OpenAIRE

    Janssen, D.; van Heck, H.W.G.M.

    2007-01-01

    textabstractIn online affiliate marketing networks advertising web sites offer their affiliates revenues based on provided web site traffic and associated leads and sales. Advertising web sites can have a network of thousands of affiliates providing them with web site traffic through hyperlinks on their web sites. Search engines such as Google, MSN, and Yahoo, consider hyperlinks as a proof of quality and/or reliability of the linked web sites, and therefore use them to determine the relevanc...

  8. Profile Popularity in a Business-oriented Online Social Network

    OpenAIRE

    Strufe, Thorsten

    2010-01-01

    Analysing Online Social Networks (OSN), voluntarily maintained and automatically exploitable databases of electronic personal information, promises a wealth of insight into their users' behavior, interest, and utilization of these currently predominant services on the Internet. To understand popularity in OSN, we monitored a large sample of profiles from a highly popular network for three months, and analysed the relation between profile properties and their impression frequency. Evaluating t...

  9. Understanding the impact of online social networks on disruptive innovation

    NARCIS (Netherlands)

    Cizel, A; Boonstra, A.; Langley, D.J.; Tan, C.W.

    2013-01-01

    In this paper we explore the state of current knowledge about online social networks (OSNs), and their role in precipitating changes in existing market structures. We do so by reviewing more than 30 recent papers from top-ranked journals in the relevant fields of study. We begin by providing a

  10. Perceived Influence of Online Social Networks on Academic ...

    African Journals Online (AJOL)

    This study investigated the perceived influence of online social networks on undergraduates' academic performance using data from a descriptive survey of 402 respondents from Babcock University, Federal University of Agriculture Abeokuta, and Olabisi Onanbanjo University. Questionnaire was used for data collection.

  11. Pharmacists on Facebook: online social networking and the profession.

    Science.gov (United States)

    Mattingly, T Joseph; Cain, Jeff; Fink, Joseph L

    2010-01-01

    To provide a brief history of Facebook and online social networking and discuss how it has contributed and can contribute in the future to a paradigm change in social communications. When student pharmacists complete school and enter practice, they encounter enhanced expectations to act appropriately and professionally. Facebook expands the dilemma of separating private and public life--a challenge for individuals in all professions. From the standpoint of a professional association, Facebook provides a tremendous opportunity to reach out to members in an unprecedented way. Pharmacy organizations are beginning to use these new tools to increase communication and dissemination of information. The popularity of Facebook has brought the issue of online social networking to the forefront of professional and organizational discussions. The issues of privacy, identity protection, and e-professionalism are likely to reappear as pharmacists and student pharmacists continue to communicate via online networks. The potential exists for organizations to harness this organizational and communication power for their own interests. Further study is needed regarding the interaction between online social networking applications and the profession of pharmacy.

  12. Leaders or Brokers? Potential Influencers in Online Parliamentary Networks

    NARCIS (Netherlands)

    Esteve Del Valle, Marc; Borge Bravo, Rosa

    2017-01-01

    The use of social media by parliamentarians is opening up a new communication arena. In Catalonia, where 85 percent of parliamentarians have a Twitter account, two questions emerge from this new social phenomenon. First, who are the opinion leaders of the parliamentarians’ online political networks,

  13. Facing scalability: Naming faces in an online social network

    NARCIS (Netherlands)

    Poppe, Ronald Walter

    Automatically naming faces in online social networks enables us to search for photos and build user face models. We consider two common weakly supervised settings where: (1) users are linked to photos, not to faces and (2) photos are not labeled but part of a user's album. The focus is on algorithms

  14. Lognormal distribution in the digg online social network

    NARCIS (Netherlands)

    Van Mieghem, P.F.A.; Blenn, N.; Doerr, C.

    2011-01-01

    We analyse the number of votes, called the digg value, which measures the impact or popularity of submitted information in the Online Social Network Digg. Experiments over five years indicate that the digg value of a story on the first frontpage follows closely a lognormal distribution. While the

  15. 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.

  16. Learning Neuroscience: An Interactive Case-Based Online Network (ICON).

    Science.gov (United States)

    Quattrochi, James J.; Pasquale, Susan; Cerva, Barbara; Lester, John E.

    2002-01-01

    Presents an interactive, case-based online network (ICON) that provides a learning environment that integrates student thinking across different concentration tracks and allows students to get away from interpreting vast amounts of available information, move toward selecting useful information, recognize discriminating findings, and build a…

  17. Virtual Social Networks Online and Mobile Systems

    Directory of Open Access Journals (Sweden)

    Maytham Safar

    2009-01-01

    Full Text Available Location-based applications are one of the most anticipated new segments of the mobile industry. These new applications are enabled by GPS-equipped phones (e.g., emergency applications, buddy finders, games, location-based advertising, etc.. These services are designed to give consumers instant access to personalized, local content of their immediate location. Some applications couple LBS with notification services, automatically alerting users when they are close to a pre-selected destination. With the advances in the Internet and communications/mobile technology, it became vital to analyze the effect of such technologies on human communications. This work studies how humans can construct social networks as a method for group communications using the available technologies. We constructed and analyzed a friends network using different parameters. The parameters that were calculated to analyze the network are the distribution sequence, characteristic path length, clustering coefficient and centrality measures. In addition, we built a PDA application that implements the concept of LBS using two system modules. In the first module, we have developed an application for entertainment purpose; an application program which enables end users to send their birth year and get their horoscope in return. The second part of the project was, to build an application, which helps people to stay in touch with their friends and family members (Find Friend. It helps users to find which of their buddies are within the same area they are in.

  18. Cognitive Benefits of Online Social Networking for Healthy Older Adults.

    Science.gov (United States)

    Myhre, Janelle W; Mehl, Matthias R; Glisky, Elizabeth L

    2017-09-01

    Research suggests that older adults who remain socially active and cognitively engaged have better cognitive function than those who are isolated and disengaged. This study examined the efficacy of learning and using an online social networking website, Facebook.com, as an intervention to maintain or enhance cognitive function in older adults. Forty-one older adults were assigned to learn and use Facebook (n = 14) or an online diary website (active control, n = 13) for 8 weeks or placed on a waitlist (n = 14). Outcome measures included neuropsychological tests of executive functions, memory, and processing speed and self-report questionnaires about social engagement. The Facebook group showed a significant increase in a composite measure of updating, an executive function factor associated with complex working memory tasks, compared to no significant change in the control groups. Other measures of cognitive function and social support showed no differential improvement in the Facebook group. Learning and using an online social networking site may provide specific benefits for complex working memory in a group of healthy older adults. This may reflect the particular cognitive demands associated with online social networking and/or the benefits of social engagement more generally. © The Author 2016. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  19. 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.

  20. Networked Participatory Scholarship: Emergent Techno-Cultural Pressures toward Open and Digital Scholarship in Online Networks

    Science.gov (United States)

    Veletsianos, George; Kimmons, Royce

    2012-01-01

    We examine the relationship between scholarly practice and participatory technologies and explore how such technologies invite and reflect the emergence of a new form of scholarship that we call "Networked Participatory Scholarship": scholars' participation in online social networks to share, reflect upon, critique, improve, validate, and…

  1. Leaking privacy and shadow profiles in online social networks.

    Science.gov (United States)

    Garcia, David

    2017-08-01

    Social interaction and data integration in the digital society can affect the control that individuals have on their privacy. Social networking sites can access data from other services, including user contact lists where nonusers are listed too. Although most research on online privacy has focused on inference of personal information of users, this data integration poses the question of whether it is possible to predict personal information of nonusers. This article tests the shadow profile hypothesis, which postulates that the data given by the users of an online service predict personal information of nonusers. Using data from a disappeared social networking site, we perform a historical audit to evaluate whether personal data of nonusers could have been predicted with the personal data and contact lists shared by the users of the site. We analyze personal information of sexual orientation and relationship status, which follow regular mixing patterns in the social network. Going back in time over the growth of the network, we measure predictor performance as a function of network size and tendency of users to disclose their contact lists. This article presents robust evidence supporting the shadow profile hypothesis and reveals a multiplicative effect of network size and disclosure tendencies that accelerates the performance of predictors. These results call for new privacy paradigms that take into account the fact that individual privacy decisions do not happen in isolation and are mediated by the decisions of others.

  2. Information filtering in evolving online networks

    Science.gov (United States)

    Chen, Bo-Lun; Li, Fen-Fen; Zhang, Yong-Jun; Ma, Jia-Lin

    2018-02-01

    Recommender systems use the records of users' activities and profiles of both users and products to predict users' preferences in the future. Considerable works towards recommendation algorithms have been published to solve the problems such as accuracy, diversity, congestion, cold-start, novelty, coverage and so on. However, most of these research did not consider the temporal effects of the information included in the users' historical data. For example, the segmentation of the training set and test set was completely random, which was entirely different from the real scenario in recommender systems. More seriously, all the objects are treated as the same, regardless of the new, the popular or obsoleted products, so do the users. These data processing methods always lose useful information and mislead the understanding of the system's state. In this paper, we detailed analyzed the difference of the network structure between the traditional random division method and the temporal division method on two benchmark data sets, Netflix and MovieLens. Then three classical recommendation algorithms, Global Ranking method, Collaborative Filtering and Mass Diffusion method, were employed. The results show that all these algorithms became worse in all four key indicators, ranking score, precision, popularity and diversity, in the temporal scenario. Finally, we design a new recommendation algorithm based on both users' and objects' first appearance time in the system. Experimental results showed that the new algorithm can greatly improve the accuracy and other metrics.

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

    Directory of Open Access Journals (Sweden)

    Florin-Alexandru LUCA

    2014-12-01

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

  4. Online Algorithms for Adaptive Optimization in Heterogeneous Delay Tolerant Networks

    Directory of Open Access Journals (Sweden)

    Wissam Chahin

    2013-12-01

    Full Text Available Delay Tolerant Networks (DTNs are an emerging type of networks which do not need a predefined infrastructure. In fact, data forwarding in DTNs relies on the contacts among nodes which may possess different features, radio range, battery consumption and radio interfaces. On the other hand, efficient message delivery under limited resources, e.g., battery or storage, requires to optimize forwarding policies. We tackle optimal forwarding control for a DTN composed of nodes of different types, forming a so-called heterogeneous network. Using our model, we characterize the optimal policies and provide a suitable framework to design a new class of multi-dimensional stochastic approximation algorithms working for heterogeneous DTNs. Crucially, our proposed algorithms drive online the source node to the optimal operating point without requiring explicit estimation of network parameters. A thorough analysis of the convergence properties and stability of our algorithms is presented.

  5. Online social networking and the experience of cyber-bullying.

    Science.gov (United States)

    O'Dea, Bridianne; Campbell, Andrew

    2012-01-01

    Online social networking sites (SNS) are popular social tools used amongst adolescents and account for much of their daily internet activity. Recently, these sites have presented opportunities for youth to experience cyber-bullying. Often resulting in psychological distress, cyber-bullying is a common experience for many young people. Continual use of SNS signifies the importance of examining its links to cyber-bullying. This study examined the relationship between online social networking and the experience of cyber-bullying. A total of 400 participants (Mage=14.31 years) completed an online survey which examined the perceived definitions and frequency of cyber-bullying. Users of SNS reported significantly higher frequencies of stranger contact compared to non-users. Spearman's rho correlations determined no significant relationship between daily time on SNS and the frequency of stranger contact. This suggests that ownership of a SNS profile may be a stronger predictor of some cyber-bullying experiences compared to time spent on these sites. Findings encourage continued research on the nature of internet activities used by young adolescents and the possible exposure to online victimization.

  6. Segmentation of online behaviour : the website & the social network

    OpenAIRE

    Slits, Petra Janna Elizabeth

    2016-01-01

    Effective marketing communication activities require companies to identify and target the right customer segments. This dissertation explores the potential of social network analysis as a tool for online behaviour segmentation. To this end, the patterns of user interactions in the Facebook page of a Portuguese company, alongside clickstream data from its website, were cluster analysed. The cluster analysis of the interaction patterns yielded four clusters, mainly based on diffe...

  7. Performing Online and Offline: How DJs Use Social Networks

    OpenAIRE

    Karnik, Mayur; Oakley, Ian; Nisi, Valentina

    2013-01-01

    Part 2: Facilitating Social Behaviour and Collaboration I; International audience; Music and online Social Network Sites (SNS) are closely intertwined in popular culture, but we know relatively little about how performers use and take advantage of such social systems. This paper investigates this space by exploring how professional DJs leverage SNS in their work. It adopts a long term mixed-methods ethnographic approach encompassing semi-structured interviews, supported by studio visits and p...

  8. The Security of Organizations and Individuals in Online Social Networks

    OpenAIRE

    Elyashar, Aviad

    2016-01-01

    The serious privacy and security problems related to online social networks (OSNs) are what fueled two complementary studies as part of this thesis. In the first study, we developed a general algorithm for the mining of data of targeted organizations by using Facebook (currently the most popular OSN) and socialbots. By friending employees in a targeted organization, our active socialbots were able to find new employees and informal organizational links that we could not find by crawling with ...

  9. Analyzing the Social Networks of High- and Low-Performing Students in Online Discussion Forums

    Science.gov (United States)

    Ghadirian, Hajar; Salehi, Keyvan; Ayub, Ahmad Fauzi Mohd

    2018-01-01

    An ego network is an individual's social network relationships with core members. In this study, the ego network parameters in online discussion spaces of high- and low-performing students were compared. The extent to which students' ego networks changed over the course were also analyzed. Participation in 7 weeks of online discussions were…

  10. Network Security Risks of Online Social Networking in the Workplace

    Science.gov (United States)

    2013-11-01

    victim’s computer into a zombie —a computer under the control of the attacker. When the malware is installed on multiple computers, the attacker can...control many of them at the same time. This zombie network is called a botnet. Thomas and Nicol [34] used a zombie emulator to communicate with servers...becomes a zombie . The victim’s zombie machine may then be used to create fake OSN accounts, acquire new friends, spam the victim’s contacts and create blog

  11. Composition and structure of a large online social network in The Netherlands.

    Science.gov (United States)

    Corten, Rense

    2012-01-01

    Limitations in data collection have long been an obstacle in research on friendship networks. Most earlier studies use either a sample of ego-networks, or complete network data on a relatively small group (e.g., a single organization). The rise of online social networking services such as Friendster and Facebook, however, provides researchers with opportunities to study friendship networks on a much larger scale. This study uses complete network data from Hyves, a popular online social networking service in The Netherlands, comprising over eight million members and over 400 million online friendship relations. In the first study of its kind for The Netherlands, I examine the structure of this network in terms of the degree distribution, characteristic path length, clustering, and degree assortativity. Results indicate that this network shares features of other large complex networks, but also deviates in other respects. In addition, a comparison with other online social networks shows that these networks show remarkable similarities.

  12. Vaccine Hesitancy and Online Information: The Influence of Digital Networks.

    Science.gov (United States)

    Getman, Rebekah; Helmi, Mohammad; Roberts, Hal; Yansane, Alfa; Cutler, David; Seymour, Brittany

    2017-12-01

    This article analyzes the digital childhood vaccination information network for vaccine-hesitant parents. The goal of this study was to explore the structure and influence of vaccine-hesitant content online by generating a database and network analysis of vaccine-relevant content. We used Media Cloud, a searchable big-data platform of over 550 million stories from 50,000 media sources, for quantitative and qualitative study of an online media sample based on keyword selection. We generated a hyperlink network map and measured indegree centrality of the sources and vaccine sentiment for a random sample of 450 stories. 28,122 publications from 4,817 sources met inclusion criteria. Clustered communities formed based on shared hyperlinks; communities tended to link within, not among, each other. The plurality of information was provaccine (46.44%, 95% confidence interval [39.86%, 53.20%]). The most influential sources were in the health community (National Institutes of Health, Centers for Disease Control and Prevention) or mainstream media ( New York Times); some user-generated sources also had strong influence and were provaccine (Wikipedia). The vaccine-hesitant community rarely interacted with provaccine content and simultaneously used primary provaccine content within vaccine-hesitant narratives. The sentiment of the overall conversation was consistent with scientific evidence. These findings demonstrate an online environment where scientific evidence online drives vaccine information outside of the vaccine-hesitant community but is also prominently used and misused within the robust vaccine-hesitant community. Future communication efforts should take current context into account; more information may not prevent vaccine hesitancy.

  13. Effective seeding strategy in evolutionary prisoner's dilemma games on online social networks

    Science.gov (United States)

    Xu, Bo; Shi, Huibin; Wang, Jianwei; Huang, Yun

    2015-04-01

    This paper explores effective seeding strategies in prisoner's dilemma game (PDG) on online social networks, i.e. the optimal strategy to obtain global cooperation with minimum cost. Three distinct seeding strategies are compared by performing computer simulations on real online social network datasets. Our finding suggests that degree centrality seeding outperforms other strategies regardless of the initial payoff setting or network size. Celebrities of online social networks play key roles in preserving cooperation.

  14. Bridging online and offline social networks: Multiplex analysis

    Science.gov (United States)

    Filiposka, Sonja; Gajduk, Andrej; Dimitrova, Tamara; Kocarev, Ljupco

    2017-04-01

    We show that three basic actor characteristics, namely normalized reciprocity, three cycles, and triplets, can be expressed using an unified framework that is based on computing the similarity index between two sets associated with the actor: the set of her/his friends and the set of those considering her/him as a friend. These metrics are extended to multiplex networks and then computed for two friendship networks generated by collecting data from two groups of undergraduate students. We found that in offline communication strong and weak ties are (almost) equally presented, while in online communication weak ties are dominant. Moreover, weak ties are much less reciprocal than strong ties. However, across different layers of the multiplex network reciprocities are preserved, while triads (measured with normalized three cycles and triplets) are not significant.

  15. Locating privileged spreaders on an online social network

    Science.gov (United States)

    Borge-Holthoefer, Javier; Rivero, Alejandro; Moreno, Yamir

    2012-06-01

    Social media have provided plentiful evidence of their capacity for information diffusion. Fads and rumors but also social unrest and riots travel fast and affect large fractions of the population participating in online social networks (OSNs). This has spurred much research regarding the mechanisms that underlie social contagion, and also who (if any) can unleash system-wide information dissemination. Access to real data, both regarding topology—the network of friendships—and dynamics—the actual way in which OSNs users interact, is crucial to decipher how the former facilitates the latter's success, understood as efficiency in information spreading. With the quantitative analysis that stems from complex network theory, we discuss who (and why) has privileged spreading capabilities when it comes to information diffusion. This is done considering the evolution of an episode of political protest which took place in Spain, spanning one month in 2011.

  16. Online Social Networks and Memory Capacity of College Students

    Directory of Open Access Journals (Sweden)

    Gabriel Valerio Ureña

    2014-10-01

    Full Text Available The aim of this research was to explore the possible existence of any relationship between the constant use of online social networks and memory capacity of college students. The research, quantitative and with exploratory scope, was conducted in a private institution of higher education in Mexico. The study subjects were 51 college students from different programs. Surveys and tests of memory capacity as data collection tools were used. The results of the study indicate that there are no significant differences between the constant use of social networks and the memorization capacity of college students. Therefore, this study does not support the hypothesis that students who spend more time on social networks have a lower memory capacity.

  17. Semantic network analysis of vaccine sentiment in online social media.

    Science.gov (United States)

    Kang, Gloria J; Ewing-Nelson, Sinclair R; Mackey, Lauren; Schlitt, James T; Marathe, Achla; Abbas, Kaja M; Swarup, Samarth

    2017-06-22

    To examine current vaccine sentiment on social media by constructing and analyzing semantic networks of vaccine information from highly shared websites of Twitter users in the United States; and to assist public health communication of vaccines. Vaccine hesitancy continues to contribute to suboptimal vaccination coverage in the United States, posing significant risk of disease outbreaks, yet remains poorly understood. We constructed semantic networks of vaccine information from internet articles shared by Twitter users in the United States. We analyzed resulting network topology, compared semantic differences, and identified the most salient concepts within networks expressing positive, negative, and neutral vaccine sentiment. The semantic network of positive vaccine sentiment demonstrated greater cohesiveness in discourse compared to the larger, less-connected network of negative vaccine sentiment. The positive sentiment network centered around parents and focused on communicating health risks and benefits, highlighting medical concepts such as measles, autism, HPV vaccine, vaccine-autism link, meningococcal disease, and MMR vaccine. In contrast, the negative network centered around children and focused on organizational bodies such as CDC, vaccine industry, doctors, mainstream media, pharmaceutical companies, and United States. The prevalence of negative vaccine sentiment was demonstrated through diverse messaging, framed around skepticism and distrust of government organizations that communicate scientific evidence supporting positive vaccine benefits. Semantic network analysis of vaccine sentiment in online social media can enhance understanding of the scope and variability of current attitudes and beliefs toward vaccines. Our study synthesizes quantitative and qualitative evidence from an interdisciplinary approach to better understand complex drivers of vaccine hesitancy for public health communication, to improve vaccine confidence and vaccination coverage

  18. Towards a deep understanding of malware propagation in online social networks

    Energy Technology Data Exchange (ETDEWEB)

    Yan, Guanhua [Los Alamos National Laboratory; Eidenbenz, Stephan [Los Alamos National Laboratory; Chen, Guanling [U OF MASSACHUSETTS LOWELL; Li, Nan [U OF MASSACHUSETTS LOWELL

    2009-01-01

    Online social networks, which have been expanding at a blistering speed in the recent years, have emerged as a popular communication infrastructure for Internet users. Meanwhile, malware that specifically targets these online social networks are also on the rise. In this work, we aim to investigate the characteristics of malware propagation in online social networks. Our study is based on a dataset collected from a real-world location-based online social network. We analyze the social structure and user activity patterns of this network. We further use extensive trace-driven simulation to study the impact of initial infection, user click probability, social structure, and activity patterns on malware propagation in online social networks. The results from this work has greatly deepened our understanding of the nature of online social network malware and also shed light on how to defend against them effectively.

  19. Characteristics of Social Network Gamers: Results of an Online Survey.

    Science.gov (United States)

    Geisel, Olga; Panneck, Patricia; Stickel, Anna; Schneider, Michael; Müller, Christian A

    2015-01-01

    Current research on Internet addiction (IA) reported moderate to high prevalence rates of IA and comorbid psychiatric symptoms in users of social networking sites (SNS) and online role-playing games. The aim of this study was to characterize adult users of an Internet multiplayer strategy game within a SNS. Therefore, we conducted an exploratory study using an online survey to assess sociodemographic variables, psychopathology, and the rate of IA in a sample of adult social network gamers by Young's Internet Addiction Test (IAT), the Toronto Alexithymia Scale (TAS-26), the Beck Depression Inventory-II (BDI-II), the Symptom Checklist-90-R (SCL-90-R), and the WHO Quality of Life-BREF (WHOQOL-BREF). All participants were listed gamers of "Combat Zone" in the SNS "Facebook." In this sample, 16.2% of the participants were categorized as subjects with IA and 19.5% fulfilled the criteria for alexithymia. Comparing study participants with and without IA, the IA group had significantly more subjects with alexithymia, reported more depressive symptoms, and showed poorer quality of life. These findings suggest that social network gaming might also be associated with maladaptive patterns of Internet use. Furthermore, a relationship between IA, alexithymia, and depressive symptoms was found that needs to be elucidated by future studies.

  20. Entrepreneur online social networks: structure, diversity and impact on start-up survival

    NARCIS (Netherlands)

    Song, Y.; Vinig, T.

    2012-01-01

    In this paper, we discuss the results of a pilot study in which we use a novel approach to collect entrepreneur online social network data from LinkedIn, Facebook and Twitter. We studied the size and structure of entrepreneur social networks by analysing the online network industry and location

  1. Analyzing the Dynamics of Communication in Online Social Networks

    Science.gov (United States)

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

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

  2. The impact of online social networks on consumers' purchasing decision : The study of food retailers

    OpenAIRE

    LI, Wei; Darban, Ayda

    2012-01-01

    The growth of online social networks around the world has created a new place of interactionand communication among people. Individuals can share their knowledge,opinions, and experiences with one other due to the online social networks providedfeatures and may have an impact on people’s behavior in terms of communicationand purchasing.The purpose of this study is to examine the impact of online social networks (Facebook)on consumers’ purchasing decision process in food retailer shops. More p...

  3. LHCb: Time structure analysis of the LHCb Online network

    CERN Multimedia

    Antichi, G; Campora Perez, D H; Liu, G; Neufeld, N; Giordano, S; Owezarski, P; Moore, A

    2013-01-01

    The LHCb Online Network is a real time high performance network, in which 350 data sources send data over a Gigabit Ethernet LAN to more than 1500 receiving nodes. The aggregated throughput of the application, called Event Building, is more than 60 GB/s. The protocol employed by LHCb makes the sending nodes transmit simultaneously portions of events to one receiving node at a time, which is selected using a credit-token scheme. The resulting traffic is very bursty and sensitive to irregularities in the temporal distribution of packet-bursts to the same destination or region of the network. In order to study the relevant properties of such a dataflow, a non-disruptive monitoring setup based on a networking capable FPGA (NetFPGA) has been deployed. The NetFPGA allows order of hundred nano-second precise time-stamping of packets. We study in detail the timing structure of the Event Building communication, and we identify potential effects of micro-bursts like buffer packet drops or jitter.

  4. Network characteristics for server selection in online games

    Science.gov (United States)

    Claypool, Mark

    2008-01-01

    Online gameplay is impacted by the network characteristics of players connected to the same server. Unfortunately, the network characteristics of online game servers are not well-understood, particularly for groups that wish to play together on the same server. As a step towards a remedy, this paper presents analysis of an extensive set of measurements of game servers on the Internet. Over the course of many months, actual Internet game servers were queried simultaneously by twenty-five emulated game clients, with both servers and clients spread out on the Internet. The data provides statistics on the uptime and populations of game servers over a month long period an an in-depth look at the suitability for game servers for multi-player server selection, concentrating on characteristics critical to playability--latency and fairness. Analysis finds most game servers have latencies suitable for third-person and omnipresent games, such as real-time strategy, sports and role-playing games, providing numerous server choices for game players. However, far fewer game servers have the low latencies required for first-person games, such as shooters or race games. In all cases, groups that wish to play together have a greatly reduced set of servers from which to choose because of inherent unfairness in server latencies and server selection is particularly limited as the group size increases. These results hold across different game types and even across different generations of games. The data should be useful for game developers and network researchers that seek to improve game server selection, whether for single or multiple players.

  5. Topological Analysis and Measurements of an Online Chinese Student Social Network

    Science.gov (United States)

    Sun, Duoyong; Wu, Jiang; Zheng, Shenghua; Hu, Bin; Carley, Kathleen M.

    Online social network attracts more researchers now. In this paper, we topologically analyze an online Chinese student social network-Xiaonei.com. We use Python language to crawl two datasets of Xiaonei in January and February, 2008. The degree distribution and small world phenomena are testified. We also use a social network analysis tool to analyze these two datasets from the viewpoint of social network structure. Seventeen measurements such as Fragmentation, Component Count, Strong/Weak are summarized to identify the exogenous attributes of Xiaonei.com. Additionally, two latent applications of online social network service are proposed in the discussion section.

  6. SEIR Model of Rumor Spreading in Online Social Network with Varying Total Population Size

    Science.gov (United States)

    Dong, Suyalatu; Deng, Yan-Bin; Huang, Yong-Chang

    2017-10-01

    Based on the infectious disease model with disease latency, this paper proposes a new model for the rumor spreading process in online social network. In this paper what we establish an SEIR rumor spreading model to describe the online social network with varying total number of users and user deactivation rate. We calculate the exact equilibrium points and reproduction number for this model. Furthermore, we perform the rumor spreading process in the online social network with increasing population size based on the original real world Facebook network. The simulation results indicate that the SEIR model of rumor spreading in online social network with changing total number of users can accurately reveal the inherent characteristics of rumor spreading process in online social network. Supported by National Natural Science Foundation of China under Grant Nos. 11275017 and 11173028

  7. SEIR Model of Rumor Spreading in Online Social Network with Varying Total Population Size

    International Nuclear Information System (INIS)

    Dong Suyalatu; Deng Yan-Bin; Huang Yong-Chang

    2017-01-01

    Based on the infectious disease model with disease latency, this paper proposes a new model for the rumor spreading process in online social network. In this paper what we establish an SEIR rumor spreading model to describe the online social network with varying total number of users and user deactivation rate. We calculate the exact equilibrium points and reproduction number for this model. Furthermore, we perform the rumor spreading process in the online social network with increasing population size based on the original real world Facebook network. The simulation results indicate that the SEIR model of rumor spreading in online social network with changing total number of users can accurately reveal the inherent characteristics of rumor spreading process in online social network . (paper)

  8. Gender Differences in the Continuance of Online Social Networks

    Science.gov (United States)

    Shi, Na; Cheung, Christy M. K.; Lee, Matthew K. O.; Chen, Huaping

    Social network sites (SNS) have become increasingly popular in the past few years benefiting from the rapid growth of Web 2.0 applications. However, research on the adoption and usage of SNS is limited. In this study, we attempt to understand users' continuance intention to use SNS and investigate the role of gender. A research model was developed and tested with 213 respondents from an online survey. The results confirm that users' continuance intention to use SNS is strongly determined by satisfaction. The effect of disconfirmation of maintaining offline contacts on satisfaction is more important for women, while the effect of disconfirmation of entertainment is more salient for men. Implications of this study for both researchers and practitioners are discussed.

  9. At the Intersection of Networks and Highly Interactive Online Games

    Science.gov (United States)

    Armitage, Grenville

    The game industry continues to evolves its techniques for extracting the most realistic 'immersion' experience for players given the vagaries on best-effort Internet service. A key challenge for service providers is understanding the characteristics of traffic imposed on networks by games, and their service quality requirements. Interactive online games are particularly susceptible to the side effects of other non-interactive (or delay- and loss-tolerant) traffic sharing next- generation access links. This creates challenges out toward the edges, where high-speed home LANs squeeze through broadband consumer access links to reach the Internet. In this chapter we identify a range of research work exploring many issues associated with the intersection of highly interactive games and the Internet, and hopefully stimulate some further thinking along these lines.

  10. Information Filtering via Heterogeneous Diffusion in Online Bipartite Networks.

    Science.gov (United States)

    Zhang, Fu-Guo; Zeng, An

    2015-01-01

    The rapid expansion of Internet brings us overwhelming online information, which is impossible for an individual to go through all of it. Therefore, recommender systems were created to help people dig through this abundance of information. In networks composed by users and objects, recommender algorithms based on diffusion have been proven to be one of the best performing methods. Previous works considered the diffusion process from user to object, and from object to user to be equivalent. We show in this work that it is not the case and we improve the quality of the recommendation by taking into account the asymmetrical nature of this process. We apply this idea to modify the state-of-the-art recommendation methods. The simulation results show that the new methods can outperform these existing methods in both recommendation accuracy and diversity. Finally, this modification is checked to be able to improve the recommendation in a realistic case.

  11. Fuzzy Modelling for Human Dynamics Based on Online Social Networks.

    Science.gov (United States)

    Cuenca-Jara, Jesus; Terroso-Saenz, Fernando; Valdes-Vela, Mercedes; Skarmeta, Antonio F

    2017-08-24

    Human mobility mining has attracted a lot of attention in the research community due to its multiple implications in the provisioning of innovative services for large metropolises. In this scope, Online Social Networks (OSN) have arisen as a promising source of location data to come up with new mobility models. However, the human nature of this data makes it rather noisy and inaccurate. In order to deal with such limitations, the present work introduces a framework for human mobility mining based on fuzzy logic. Firstly, a fuzzy clustering algorithm extracts the most active OSN areas at different time periods. Next, such clusters are the building blocks to compose mobility patterns. Furthermore, a location prediction service based on a fuzzy rule classifier has been developed on top of the framework. Finally, both the framework and the predictor has been tested with a Twitter and Flickr dataset in two large cities.

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

    DEFF Research Database (Denmark)

    Trier, Matthias; Hillmann, Robert

    2017-01-01

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

  13. Professional Online Presence and Learning Networks: Educating for Ethical Use of Social Media

    Science.gov (United States)

    Forbes, Dianne

    2017-01-01

    In a teacher education context, this study considers the use of social media for building a professional online presence and learning network. This article provides an overview of uses of social media in teacher education, presents a case study of key processes in relation to professional online presence and learning networks, and highlights…

  14. Can online networks provide quality answers to questions about occupational safety and health?

    NARCIS (Netherlands)

    Rhebergen, Martijn D. F.; Lenderink, Annet F.; van Dijk, Frank J. H.; Hulshof, Carel T. J.

    2012-01-01

    Objectives To assess whether experts can provide high-quality answers to occupational safety and health (OSH) questions in online Question & Answer (Q&A) networks. Methods The authors evaluated the quality of answers provided by qualified experts in two Dutch online networks: ArboAntwoord and the

  15. "Newbies" and "Celebrities": Detecting Social Roles in an Online Network of Teachers via Participation Patterns

    Science.gov (United States)

    Smith Risser, H.; Bottoms, SueAnn

    2014-01-01

    The advent of social networking tools allows teachers to create online networks and share information. While some virtual networks have a formal structure and defined boundaries, many do not. These unstructured virtual networks are difficult to study because they lack defined boundaries and a formal structure governing leadership roles and the…

  16. Facebook and romantic relationships: intimacy and couple satisfaction associated with online social network use.

    Science.gov (United States)

    Hand, Matthew M; Thomas, Donna; Buboltz, Walter C; Deemer, Eric D; Buyanjargal, Munkhsanaa

    2013-01-01

    Online social networks, such as Facebook, have gained immense popularity and potentially affect the way people build and maintain interpersonal relationships. The present study sought to examine time spent on online social networks, as it relates to intimacy and relationship satisfaction experienced in romantic relationships. Results did not find relationships between an individual's usage of online social networks and his/her perception of relationship satisfaction and intimacy. However, the study found a negative relationship between intimacy and the perception of a romantic partner's use of online social networks. This finding may allude to an attributional bias in which individuals are more likely to perceive a partner's usage as negative compared to their own usage. Additionally, it was found that intimacy mediates the relationship between online social network usage and overall relationship satisfaction, which suggests that the level of intimacy experienced in a relationship may serve as a buffer that protects the overall level of satisfaction.

  17. Social selection and peer influence in an online social network.

    Science.gov (United States)

    Lewis, Kevin; Gonzalez, Marco; Kaufman, Jason

    2012-01-03

    Disentangling the effects of selection and influence is one of social science's greatest unsolved puzzles: Do people befriend others who are similar to them, or do they become more similar to their friends over time? Recent advances in stochastic actor-based modeling, combined with self-reported data on a popular online social network site, allow us to address this question with a greater degree of precision than has heretofore been possible. Using data on the Facebook activity of a cohort of college students over 4 years, we find that students who share certain tastes in music and in movies, but not in books, are significantly likely to befriend one another. Meanwhile, we find little evidence for the diffusion of tastes among Facebook friends-except for tastes in classical/jazz music. These findings shed light on the mechanisms responsible for observed network homogeneity; provide a statistically rigorous assessment of the coevolution of cultural tastes and social relationships; and suggest important qualifications to our understanding of both homophily and contagion as generic social processes.

  18. Modern Social Support Structures: Online Social Networks and their Implications for Social Workers

    Directory of Open Access Journals (Sweden)

    Kala Chakradhar

    2009-03-01

    Full Text Available Mapping and assessing social networks and the quality of their social support is a valuable intervention strategy for social workers. These networks have now spread onto the digital realm in the form of Online Social Networks (OSNs. This study investigated the nature of social support provided by such networks to their users in a rural mid-South University (USA and explored parallels with the current understanding of social support in conventional social networks. A web-based survey administered to college students revealed that users of these online networks were predominantly undergraduate first year students, female, single, unemployed and from a variety of academic disciplines. The examination of the components of OSNs appears to mirror those of offline networks. They also seem to complement the effects of each other while contributing to an individual's support system. The paper concludes with critical implications of such online social networking for University students and social workers in practice and education.

  19. Using Online Social Networking to Enhance Social Connectedness and Social Support for the Elderly

    OpenAIRE

    Goswami, Suparna;Köbler, Felix;Leimeister, Jan Marco;Krcmar, Helmut

    2014-01-01

    Social integration is crucial for the overall well-being of the elderly who are more prone to social exclusion because of the natural aging process. We propose online social networking as means to enhance social connectedness and social support ? two aspects of social networks that have significant implications for the well-being of elderly. While prior research investigating the benefits of online social networking has primarily focused on user groups such as teenagers and college students, ...

  20. Using Online Social Networking to Enhance Social Connectedness and Social Support for the Elderly

    OpenAIRE

    Goswami, Suparna; Köbler, Felix; Leimeister, Jan Marco; Krcmar, Helmut

    2010-01-01

    Social integration is crucial for the overall well-being of the elderly who are more prone to social exclusion because of the natural aging process. We propose online social networking as means to enhance social connectedness and social support – two aspects of social networks that have significant implications for the well-being of elderly. While prior research investigating the benefits of online social networking has primarily focused on user groups such as teenagers and college students, ...

  1. A Comparison of Online Social Networks and Real-Life Social Networks: A Study of Sina Microblogging

    Directory of Open Access Journals (Sweden)

    Dayong Zhang

    2014-01-01

    Full Text Available Online social networks appear to enrich our social life, which raises the question whether they remove cognitive constraints on human communication and improve human social capabilities. In this paper, we analyze the users' following and followed relationships based on the data of Sina Microblogging and reveal several structural properties of Sina Microblogging. Compared with real-life social networks, our results confirm some similar features. However, Sina Microblogging also shows its own specialties, such as hierarchical structure and degree disassortativity, which all mark a deviation from real-life social networks. The low cost of the online network forms a broader perspective, and the one-way link relationships make it easy to spread information, but the online social network does not make too much difference in the creation of strong interpersonal relationships. Finally, we describe the mechanisms for the formation of these characteristics and discuss the implications of these structural properties for the real-life social networks.

  2. Addiction to Internet Use, Online Gaming, and Online Social Networking Among Young Adults in China, Singapore, and the United States.

    Science.gov (United States)

    Tang, Catherine So-Kum; Koh, Yee Woen; Gan, YiQun

    2017-11-01

    The current study investigated the rates of addictions to Internet use, online gaming, and online social networking as well as their associations with depressive symptoms among young adults in China, Singapore, and the United States. A total of 3267 undergraduate students were recruited. Psychological instruments were used to assess various Internet-related addictions and depressive symptoms. Male students were more addicted to Internet and online gaming whereas female students were more addicted to online social networking. Compared with students in the United States, Chinese and Singaporean students were more addicted to Internet use and online social networking but less to online gaming. The odds of depression among students with addiction to various Internet-related addictions were highest in China. Internet-related addiction is a new public health concern of young adults, especially in the Asia-Pacific regions. It is found to associate with depressive symptoms. Strategies should address this phenomenon with attention to specific needs of gender and region while managing mood disturbances.

  3. Similarity between community structures of different online social networks and its impact on underlying community detection

    Science.gov (United States)

    Fan, W.; Yeung, K. H.

    2015-03-01

    As social networking services are popular, many people may register in more than one online social network. In this paper we study a set of users who have accounts of three online social networks: namely Foursquare, Facebook and Twitter. Community structure of this set of users may be reflected in these three online social networks. Therefore, high correlation between these reflections and the underlying community structure may be observed. In this work, community structures are detected in all three online social networks. Also, we investigate the similarity level of community structures across different networks. It is found that they show strong correlation with each other. The similarity between different networks may be helpful to find a community structure close to the underlying one. To verify this, we propose a method to increase the weights of some connections in networks. With this method, new networks are generated to assist community detection. By doing this, value of modularity can be improved and the new community structure match network's natural structure better. In this paper we also show that the detected community structures of online social networks are correlated with users' locations which are identified on Foursquare. This information may also be useful for underlying community detection.

  4. Understanding the process of social network evolution: Online-offline integrated analysis of social tie formation.

    Science.gov (United States)

    Kwak, Doyeon; Kim, Wonjoon

    2017-01-01

    It is important to consider the interweaving nature of online and offline social networks when we examine social network evolution. However, it is difficult to find any research that examines the process of social tie formation from an integrated perspective. In our study, we quantitatively measure offline interactions and examine the corresponding evolution of online social network in order to understand the significance of interrelationship between online and offline social factors in generating social ties. We analyze the radio signal strength indicator sensor data from a series of social events to understand offline interactions among the participants and measure the structural attributes of their existing online Facebook social networks. By monitoring the changes in their online social networks before and after offline interactions in a series of social events, we verify that the ability to develop an offline interaction into an online friendship is tied to the number of social connections that participants previously had, while the presence of shared mutual friends between a pair of participants disrupts potential new connections within the pre-designed offline social events. Thus, while our integrative approach enables us to confirm the theory of preferential attachment in the process of network formation, the common neighbor theory is not supported. Our dual-dimensional network analysis allows us to observe the actual process of social network evolution rather than to make predictions based on the assumption of self-organizing networks.

  5. Characteristics of Social Network Gamers: in between Social Networking and Online Role-Playing Games

    Directory of Open Access Journals (Sweden)

    Olga eGeisel

    2015-07-01

    Full Text Available Current research on internet addiction (IA reported moderate to high prevalence rates of IA and comorbid psychiatric symptoms in users of social networking sites (SNS and online role-playing games. The aim of this study was to characterise adult users of an internet multiplayer strategy game within a SNS. Therefore, we conducted an exploratory study using an online survey to assess sociodemographic variables, psychopathology and the rate of IA in a sample of adult social network gamers by Young´s Internet Addiction Test (IAT, the Toronto Alexithymia Scale (TAS, the Beck Depression Inventory II (BDI-II, the Symptom Checklist-90-R (SCL-90-R and the WHO Quality of Life-BREF (WHOQOL-BREF. All participants were listed gamers of combat zone in the SNS Facebook. In the IAT analysis, 16.2 % of the participants (n = 60 were categorized as subjects with IA and 19.5 % (n = 72 fulfilled the criteria for alexithymia. Comparing study participants with and without IA, the IA group had significantly more subjects with alexithymia, reported more depressive symptoms, and showed poorer quality of life. These findings suggest that social network gaming might also be associated with maladaptive patterns of internet use. Furthermore, a relationship between IA, alexithymia and depressive symptoms was found that needs to be elucidated by future studies.

  6. Monitoring of Students' Interaction in Online Learning Settings by Structural Network Analysis and Indicators.

    Science.gov (United States)

    Ammenwerth, Elske; Hackl, Werner O

    2017-01-01

    Learning as a constructive process works best in interaction with other learners. Support of social interaction processes is a particular challenge within online learning settings due to the spatial and temporal distribution of participants. It should thus be carefully monitored. We present structural network analysis and related indicators to analyse and visualize interaction patterns of participants in online learning settings. We validate this approach in two online courses and show how the visualization helps to monitor interaction and to identify activity profiles of learners. Structural network analysis is a feasible approach for an analysis of the intensity and direction of interaction in online learning settings.

  7. Novel Online Dimensionality Reduction Method with Improved Topology Representing and Radial Basis Function Networks

    Science.gov (United States)

    Ni, Shengqiao; Lv, Jiancheng; Cheng, Zhehao; Li, Mao

    2015-01-01

    This paper presents improvements to the conventional Topology Representing Network to build more appropriate topology relationships. Based on this improved Topology Representing Network, we propose a novel method for online dimensionality reduction that integrates the improved Topology Representing Network and Radial Basis Function Network. This method can find meaningful low-dimensional feature structures embedded in high-dimensional original data space, process nonlinear embedded manifolds, and map the new data online. Furthermore, this method can deal with large datasets for the benefit of improved Topology Representing Network. Experiments illustrate the effectiveness of the proposed method. PMID:26161960

  8. Novel Online Dimensionality Reduction Method with Improved Topology Representing and Radial Basis Function Networks.

    Directory of Open Access Journals (Sweden)

    Shengqiao Ni

    Full Text Available This paper presents improvements to the conventional Topology Representing Network to build more appropriate topology relationships. Based on this improved Topology Representing Network, we propose a novel method for online dimensionality reduction that integrates the improved Topology Representing Network and Radial Basis Function Network. This method can find meaningful low-dimensional feature structures embedded in high-dimensional original data space, process nonlinear embedded manifolds, and map the new data online. Furthermore, this method can deal with large datasets for the benefit of improved Topology Representing Network. Experiments illustrate the effectiveness of the proposed method.

  9. Novel Online Dimensionality Reduction Method with Improved Topology Representing and Radial Basis Function Networks.

    Science.gov (United States)

    Ni, Shengqiao; Lv, Jiancheng; Cheng, Zhehao; Li, Mao

    2015-01-01

    This paper presents improvements to the conventional Topology Representing Network to build more appropriate topology relationships. Based on this improved Topology Representing Network, we propose a novel method for online dimensionality reduction that integrates the improved Topology Representing Network and Radial Basis Function Network. This method can find meaningful low-dimensional feature structures embedded in high-dimensional original data space, process nonlinear embedded manifolds, and map the new data online. Furthermore, this method can deal with large datasets for the benefit of improved Topology Representing Network. Experiments illustrate the effectiveness of the proposed method.

  10. Communication, collaboration and identity: factor analysis of academics’ perceptions of online networking

    Directory of Open Access Journals (Sweden)

    Katy Jordan

    2018-04-01

    Full Text Available Since the advent of online social networking sites, much has been written about their potential for transforming academia, as communication and collaboration underpin many scholarly activities. However, the extent to which these benefits are being realised in practice is unclear. As the uptake of tools by academics continues to grow, there is a question as to whether differences exist in their use and if any patterns or underlying factors are at play. This article presents the results of an online survey addressing this gap. A disciplinary divide was evident in terms of preferred academic social networking platforms, while perceptions about how academics use online networking for different purposes are linked to job position. Exploratory factor analysis identified four components representing different strategies used by academics in their approaches to online networking, including maintaining a personal learning network, promoting the professional self, seeking and promoting publications, and advancing careers.

  11. Student Support Networks in Online Doctoral Programs: Exploring Nested Communities

    OpenAIRE

    Sharla Berry

    2017-01-01

    Aim/Purpose: Enrollment in online doctoral programs has grown over the past decade. A sense of community, defined as feelings of closeness within a social group, is vital to retention, but few studies have explored how online doctoral students create community. Background: In this qualitative case study, I explore how students in one online doctoral program created a learning community. Methodology: Data for the study was drawn from 60 hours of video footage from six online courses,...

  12. Offline Social Relationships and Online Cancer Communication: Effects of Social and Family Support on Online Social Network Building.

    Science.gov (United States)

    Namkoong, Kang; Shah, Dhavan V; Gustafson, David H

    2017-11-01

    This study investigates how social support and family relationship perceptions influence breast cancer patients' online communication networks in a computer-mediated social support (CMSS) group. To examine social interactions in the CMSS group, we identified two types of online social networks: open and targeted communication networks. The open communication network reflects group communication behaviors (i.e., one-to-many or "broadcast" communication) in which the intended audience is not specified; in contrast, the targeted communication network reflects interpersonal discourses (i.e., one-to-one or directed communication) in which the audience for the message is specified. The communication networks were constructed by tracking CMSS group usage data of 237 breast cancer patients who participated in one of two National Cancer Institute-funded randomized clinical trials. Eligible subjects were within 2 months of a diagnosis of primary breast cancer or recurrence at the time of recruitment. Findings reveal that breast cancer patients who perceived less availability of offline social support had a larger social network size in the open communication network. In contrast, those who perceived less family cohesion had a larger targeted communication network in the CMSS group, meaning they were inclined to use the CMSS group for developing interpersonal relationships.

  13. Crawling and Detecting Community Structure in Online Social Networks using Local Information

    NARCIS (Netherlands)

    Blenn, N.; Doerr, C.; Van Kester, B.; Van Mieghem, P.

    As Online Social Networks (OSNs) become an intensive sub- ject of research for example in computer science, networking, social sci- ences etc., a growing need for valid and useful datasets is present. The time taken to crawl the network is however introducing a bias which should be minimized. Usual

  14. Consumers' online social network topologies and health behaviours.

    Science.gov (United States)

    Lau, Annie Y S; Dunn, Adam; Mortimer, Nathan; Proudfoot, Judith; Andrews, Annie; Liaw, Siaw-Teng; Crimmins, Jacinta; Arguel, Amaël; Coiera, Enrico

    2013-01-01

    Personally controlled health management systems (PCHMS) often consist of multiple design features. Yet, they currently lack empirical evidence on how consumers use and engage with a PCHMS. An online prospective study was designed to investigate how 709 consumers used a web-based PCHMS to manage their physical and emotional wellbeing over five months. The web-based PCHMS, Healthy.me, was developed at UNSW and incorporates an untethered personal health record, consumer care pathways, forums, polls, diaries, and messaging links with healthcare professionals. The two PCHMS features that consumers used most frequently, found most useful, and engaging were the social features, i.e. forum and poll. Compared to participants who did not use any PCHMS social feature, those who used either the poll or the forum were 12.3% more likely to visit a healthcare professional (P=0.001) during the study. Social network analysis of forums revealed a spectrum of social interaction patterns - from question-and-answer structures to community discussions. This study provides a basis for understanding how a PCHMS can be used as a socially-driven intervention to influence consumers' health behaviours.

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

    Science.gov (United States)

    Rizos, Georgios; Papadopoulos, Symeon; Kompatsiaris, Yiannis

    2017-01-01

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

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

    Directory of Open Access Journals (Sweden)

    Georgios Rizos

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

  17. Popularity Evaluation Model for Microbloggers Online Social Network

    Directory of Open Access Journals (Sweden)

    Xia Zhang

    2014-01-01

    Full Text Available Recently, microblogging is widely studied by the researchers in the domain of the online social network (OSN. How to evaluate the popularities of microblogging users is an important research field, which can be applied to commercial advertising, user behavior analysis and information dissemination, and so forth. Previous studies on the evaluation methods cannot effectively solve and accurately evaluate the popularities of the microbloggers. In this paper, we proposed an electromagnetic field theory based model to analyze the popularities of microbloggers. The concept of the source in microblogging field is first put forward, which is based on the concept of source in the electromagnetic field; then, one’s microblogging flux is calculated according to his/her behaviors (send or receive feedbacks on the microblogging platform; finally, we used three methods to calculate one’s microblogging flux density, which can represent one’s popularity on the microblogging platform. In the experimental work, we evaluated our model using real microblogging data and selected the best one from the three popularity measure methods. We also compared our model with the classic PageRank algorithm; and the results show that our model is more effective and accurate to evaluate the popularities of the microbloggers.

  18. Analyzing hidden populations online: topic, emotion, and social network of HIV-related users in the largest Chinese online community.

    Science.gov (United States)

    Liu, Chuchu; Lu, Xin

    2018-01-05

    Traditional survey methods are limited in the study of hidden populations due to the hard to access properties, including lack of a sampling frame, sensitivity issue, reporting error, small sample size, etc. The rapid increase of online communities, of which members interact with others via the Internet, have generated large amounts of data, offering new opportunities for understanding hidden populations with unprecedented sample sizes and richness of information. In this study, we try to understand the multidimensional characteristics of a hidden population by analyzing the massive data generated in the online community. By elaborately designing crawlers, we retrieved a complete dataset from the "HIV bar," the largest bar related to HIV on the Baidu Tieba platform, for all records from January 2005 to August 2016. Through natural language processing and social network analysis, we explored the psychology, behavior and demand of online HIV population and examined the network community structure. In HIV communities, the average topic similarity among members is positively correlated to network efficiency (r = 0.70, p Online communities have generated copious amounts of data offering new opportunities for understanding hidden populations with unprecedented sample sizes and richness of information. It is recommended that support through online services for HIV/AIDS consultation and diagnosis be improved to avoid privacy concerns and social discrimination in China.

  19. The Challenges to Connectivist Learning on Open Online Networks: Learning Experiences during a Massive Open Online Course

    Directory of Open Access Journals (Sweden)

    Rita Kop

    2011-03-01

    Full Text Available Self-directed learning on open online networks is now a possibility as communication and resources can be combined to create learning environments. But is it really? There are some challenges that might prevent learners from having a quality learning experience. This paper raises questions on levels of learner autonomy, presence, and critical literacies required in active connectivist learning.

  20. Employment relations: A data driven analysis of job markets using online job boards and online professional networks

    CSIR Research Space (South Africa)

    Marivate, Vukosi N

    2017-08-01

    Full Text Available of the South African job market. We do this by analysing data from career websites as well as a South African online professional networks. Our goals are to be able to group jobs given their descriptions, characterise career paths as well as to have some...

  1. Online social networks for patient involvement and recruitment in clinical research.

    Science.gov (United States)

    Ryan, Gemma Sinead

    2013-01-01

    To review current literature and discuss the potential of online social networking to engage patients and the public and recruit and retain participants in clinical research. Online social networking is becoming a large influence on people's daily lives. Clinical research faces several challenges, with an increasing need to engage with patients and the public and for studies to recruit and retain increasing numbers of participants, particularly in under-served, under-represented and hard to reach groups and communities. Searches were conducted using EMBASE, BNI, ERIC, CINAHL, PSYCHinfo online databases and Google Scholar to identify any grey or unpublished literature that may be available. Review methods This is a methodology paper. Online social networking is a successful, cost-effective and efficient method by which to target and recruit a wide range of communities, adolescents, young people and underserved populations into quantitative and qualitative research. Retention of participants in longitudinal studies could be improved using social networks such as Facebook. Evidence indicates that a mixed approach to recruitment using social networking and traditional methods is most effective. Further research is required to strengthen the evidence available, especially in dissemination of research through online social networks. Researchers should consider using online social networking as a method of engaging the public, and also for the recruitment and follow up of participants.

  2. The Relationship Between Online Social Networking and Depression: A Systematic Review of Quantitative Studies.

    Science.gov (United States)

    Baker, David A; Algorta, Guillermo Perez

    2016-11-01

    Online social networking sites (SNSs) such as Facebook, Twitter, and MySpace are used by billions of people every day to communicate and interact with others. There has been increasing interest in the potential impact of online social networking on wellbeing, with a broadening body of new research into factors associated with both positive and negative mental health outcomes such as depression. This systematic review of empirical studies (n = 30) adds to existing research in this field by examining current quantitative studies focused on the relationship between online social networking and symptoms of depression. The academic databases PsycINFO, Web of Science, CINAHL, MEDLINE, and EMBASE were searched systematically using terms related to online social networking and depression. Reporting quality was critically appraised and the findings discussed with reference to their wider implications. The findings suggest that the relationship between online social networking and symptoms of depression may be complex and associated with multiple psychological, social, behavioral, and individual factors. Furthermore, the impact of online social networking on wellbeing may be both positive and negative, highlighting the need for future research to determine the impact of candidate mediators and moderators underlying these heterogeneous outcomes across evolving networks.

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

    OpenAIRE

    Davoust, Alan; Esfandiari, Babak

    2016-01-01

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

  4. Healthy connections: online social networks and their potential for peer support.

    Science.gov (United States)

    O'Dea, Bridianne; Campbell, Andrew

    2011-01-01

    Social and professional support for mental health is lacking in many rural areas - highlighting the need for innovative ways to improve access to services. This study explores the potential of online social networking as an avenue for peer support. Using a cross sectional survey, 74 secondary students answered questions relating to internet use, online social network use and perceptions of mental health support. Over half of the sample had experienced a need for mental health support with 53% of participants turning to the internet. Results indicate that online social networking sites were used regularly by 82% of the sample and 47% believed these sites could help with mental health problems. The study concluded that online social networking sites may be able to link young people together with others in similar situations. The popularity and frequency of use may allow these sites to provide information, advice and direction for those seeking help.

  5. Community (in) Colleges: The Relationship Between Online Network Involvement and Academic Outcomes at a Community College

    Science.gov (United States)

    Evans, Eliza D.; McFarland, Daniel A.; Rios-Aguilar, Cecilia; Deil-Amen, Regina

    2016-01-01

    Objective: This study explores the relationship between online social network involvement and academic outcomes among community college students. Prior theory hypothesizes that socio-academic moments are especially important for the integration of students into community colleges and that integration is related to academic outcomes. Online social…

  6. Social and Virtual Networks: Evaluating Synchronous Online Interviewing Using Instant Messenger

    Science.gov (United States)

    Hinchcliffe, Vanessa; Gavin, Helen

    2009-01-01

    This paper describes an evaluation of the quality and utility of synchronous online interviewing for data collection in social network research. Synchronous online interviews facilitated by Instant Messenger as the communication medium, were undertaken with ten final year university students. Quantitative and qualitative content analysis of…

  7. Empirical analysis of online social networks in the age of Web 2.0

    Science.gov (United States)

    Fu, Feng; Liu, Lianghuan; Wang, Long

    2008-01-01

    Today the World Wide Web is undergoing a subtle but profound shift to Web 2.0, to become more of a social web. The use of collaborative technologies such as blogs and social networking site (SNS) leads to instant online community in which people communicate rapidly and conveniently with each other. Moreover, there are growing interest and concern regarding the topological structure of these new online social networks. In this paper, we present empirical analysis of statistical properties of two important Chinese online social networks-a blogging network and an SNS open to college students. They are both emerging in the age of Web 2.0. We demonstrate that both networks possess small-world and scale-free features already observed in real-world and artificial networks. In addition, we investigate the distribution of topological distance. Furthermore, we study the correlations between degree (in/out) and degree (in/out), clustering coefficient and degree, popularity (in terms of number of page views) and in-degree (for the blogging network), respectively. We find that the blogging network shows disassortative mixing pattern, whereas the SNS network is an assortative one. Our research may help us to elucidate the self-organizing structural characteristics of these online social networks embedded in technical forms.

  8. The relationship between online social networking and depression:a systematic review of quantitative studies

    OpenAIRE

    Baker, David; Perez Algorta, Guillermo Daniel

    2016-01-01

    Online social networking sites (SNSs) such as Facebook, Twitter, and MySpace are used by billions of people every day to communicate and interact with others. There has been increasing interest in the potential impact of online social networking on wellbeing, with a broadening body of new research into factors associated with both positive and negative mental health outcomes such as depression. This systematic review of empirical studies (n=30) adds to existing research in this field by exami...

  9. Factors Affecting Customers Online Search Intention and Online Purchase Intention Using Social Networks: Case Study of Online Shop on Instagram

    OpenAIRE

    Putri, Jessica Wongso

    2015-01-01

    As the internet USAge in Indonesia keep growing rapidly, it creates big opportunities for apparel online shops owner to market their products through many popular online media, especially Instagram. However, many online shop owners have no clue how to market their apparel product effectively via Instagram. Therefore, this research created to analyze the factors that can influence the customers' purchase intention. Those factors are Utilitarian Value of Internet Information Search, Hedonic Va...

  10. A radix-4 on-line division design and its application to networks of on-line modules

    Science.gov (United States)

    Tenca, Alexandre F.; Shantilal, Ajay; Sinky, Mohammed

    2003-12-01

    On-line division is one of the slowest operations among the basic arithmetic operations and naturally becomes a bottleneck in networks of on-line modules that use it. A higher radix divider has a good potential to attain higher throughput than radix-2 dividers and therefore improve the overall throughput of networks where division is needed. The improvement in throughput when using radix 4 is not straightforward since several components of the divider become more complex than in the radix-2 case. Previously proposed radix-4 designs were based on operand pre-scaling to simplify the selection function and reduce the critical path delay, at the cost of more complexity in the algorithm conditions and operations, plus a variable on-line delay, which is a very unattractive feature when small precision values are used (usually the case for DSP). These designs include several phases for pre-scaling and actual division. This paper proposes a design approach based on overlapped replication that results in a radix-4 on-line division module with low algorithm complexity, single division phase, less restrictions to the input values, and a small and fixed on-line delay.

  11. Quantifying discrepancies in opinion spectra from online and offline networks.

    Science.gov (United States)

    Lee, Deokjae; Hahn, Kyu S; Yook, Soon-Hyung; Park, Juyong

    2015-01-01

    Online social media such as Twitter are widely used for mining public opinions and sentiments on various issues and topics. The sheer volume of the data generated and the eager adoption by the online-savvy public are helping to raise the profile of online media as a convenient source of news and public opinions on social and political issues as well. Due to the uncontrollable biases in the population who heavily use the media, however, it is often difficult to measure how accurately the online sphere reflects the offline world at large, undermining the usefulness of online media. One way of identifying and overcoming the online-offline discrepancies is to apply a common analytical and modeling framework to comparable data sets from online and offline sources and cross-analyzing the patterns found therein. In this paper we study the political spectra constructed from Twitter and from legislators' voting records as an example to demonstrate the potential limits of online media as the source for accurate public opinion mining, and how to overcome the limits by using offline data simultaneously.

  12. Quantifying discrepancies in opinion spectra from online and offline networks.

    Directory of Open Access Journals (Sweden)

    Deokjae Lee

    Full Text Available Online social media such as Twitter are widely used for mining public opinions and sentiments on various issues and topics. The sheer volume of the data generated and the eager adoption by the online-savvy public are helping to raise the profile of online media as a convenient source of news and public opinions on social and political issues as well. Due to the uncontrollable biases in the population who heavily use the media, however, it is often difficult to measure how accurately the online sphere reflects the offline world at large, undermining the usefulness of online media. One way of identifying and overcoming the online-offline discrepancies is to apply a common analytical and modeling framework to comparable data sets from online and offline sources and cross-analyzing the patterns found therein. In this paper we study the political spectra constructed from Twitter and from legislators' voting records as an example to demonstrate the potential limits of online media as the source for accurate public opinion mining, and how to overcome the limits by using offline data simultaneously.

  13. Preferential Attachment in Online Networks: Measurement and Explanations

    NARCIS (Netherlands)

    Kunegis, J; Blattner, M; Moser, C.

    2013-01-01

    We perform an empirical study of the preferential attachment phenomenon in temporal networks and show that on the Web, networks follow a nonlinear preferential attachment model in which the exponent depends on the type of network considered. The classical preferential attachment model for networks

  14. The Online Social Networking of Cyberspace: A Study on the Development of an Online Social Network Project and the Sport Industry's Perception of Its Relative Advantage

    Science.gov (United States)

    Liptrap, Timothy John

    2011-01-01

    This exploratory case study examined online social networking (OSN), and the perceptions of Sport Marketing students and sport industry professional as to the relative advantage of the OSN tools in the marketplace. The conceptual framework for this study was based on Boyer's (1990) concepts of Scholarship of Teaching and Learning (SoTL), and the…

  15. An evolution model of online social networks based on “Sina micro-blog”

    Directory of Open Access Journals (Sweden)

    ZHANG Xin

    2016-06-01

    Full Text Available The impact of online social networks and the necessity to sustain their rapid growth emphasize the importance to unravel the laws governing their evolution. With online data crawled from “Sina micro-blog”, we divide the entire users into opinion leaders and ordinary microbloggers without verification. This allows us to illustrate a quantitative two-layer model to reproduce the evolution of the online social networks from the birth of it, which is a visual framework for micro-blog users ′ behaviors. The empirical study of the model shows that the different influence between ordinary users and opinion leaders and the viral spreading mechanism and mass media influence govern the evolution of online social networks. At the end we verify the accuracy of our model with real “Sina micro-blog”dataset. Furthermore, considering the complexity of microbloggers, we can develop the information dissemination to show the mutual impact of various social values.

  16. Online reputation on the example of the social network Instagram

    OpenAIRE

    Mihaljević, Dalia

    2016-01-01

    Online reputacija u kombinaciji sa sve popularnijom društvenom mrežom Instagram jasno odražava ljudske potrebe i navike u današnjem digitalnom dobu. Rad donosi dva teorijska poglavlja, jedno o online reputaciji, drugo o Instagramu i to kroz prikaz osnovnih definicija i primjera mnogih digitalnih stručnjaka. Istraživanjem se nastojalo saznati stavove ispitanika vezane uz njihovo shvaćanje online reputacije, ali i načine na koje koriste društvenu mrežu Instagram. Rezultati otkrivaju da je i...

  17. Usefulness of Social Network Sites for Adolescents' Development of Online Career Skills

    Science.gov (United States)

    Rutten, Mariëlle; Ros, Anje; Kuijpers, Marinka; Kreijns, Karel

    2016-01-01

    Schools have an important role in teaching students how to use Social Network Site (SNS) for career purposes. This involves the opportunity for students to practice online career skills. Different types of digital environments are available for schools. There are SNS designed to enable users to interact and network. In addition there are digital…

  18. Online multistep-ahead inundation depth forecasts by recurrent NARX networks

    Directory of Open Access Journals (Sweden)

    H.-Y. Shen

    2013-03-01

    Full Text Available Various types of artificial neural networks (ANNs have been successfully applied in hydrological fields, but relatively scant on multistep-ahead flood inundation forecasting, which is very difficult to achieve, especially when dealing with forecasts without regular observed data. This study proposes a recurrent configuration of nonlinear autoregressive with exogenous inputs (NARX network, called R-NARX, to forecast multistep-ahead inundation depths in an inundation area. The proposed R-NARX is constructed based on the recurrent neural network (RNN, which is commonly used for modeling nonlinear dynamical systems. The models were trained and tested based on a large number of inundation data generated by a well validated two-dimensional simulation model at thirteen inundation-prone sites in Yilan County, Taiwan. We demonstrate that the R-NARX model can effectively inhibit error growth and accumulation when being applied to online multistep-ahead inundation forecasts over a long lasting forecast period. For comparison, a feedforward time-delay and an online feedback configuration of NARX networks (T-NARX and O-NARX were performed. The results show that (1 T-NARX networks cannot make online forecasts due to unavailable inputs in the constructed networks even though they provide the best performances for reference only; and (2 R-NARX networks consistently outperform O-NARX networks and can be adequately applied to online multistep-ahead forecasts of inundation depths in the study area during typhoon events.

  19. Toward Predicting Social Support Needs in Online Health Social Networks.

    Science.gov (United States)

    Choi, Min-Je; Kim, Sung-Hee; Lee, Sukwon; Kwon, Bum Chul; Yi, Ji Soo; Choo, Jaegul; Huh, Jina

    2017-08-02

    While online health social networks (OHSNs) serve as an effective platform for patients to fulfill their various social support needs, predicting the needs of users and providing tailored information remains a challenge. The objective of this study was to discriminate important features for identifying users' social support needs based on knowledge gathered from survey data. This study also provides guidelines for a technical framework, which can be used to predict users' social support needs based on raw data collected from OHSNs. We initially conducted a Web-based survey with 184 OHSN users. From this survey data, we extracted 34 features based on 5 categories: (1) demographics, (2) reading behavior, (3) posting behavior, (4) perceived roles in OHSNs, and (5) values sought in OHSNs. Features from the first 4 categories were used as variables for binary classification. For the prediction outcomes, we used features from the last category: the needs for emotional support, experience-based information, unconventional information, and medical facts. We compared 5 binary classifier algorithms: gradient boosting tree, random forest, decision tree, support vector machines, and logistic regression. We then calculated the scores of the area under the receiver operating characteristic (ROC) curve (AUC) to understand the comparative effectiveness of the used features. The best performance was AUC scores of 0.89 for predicting users seeking emotional support, 0.86 for experience-based information, 0.80 for unconventional information, and 0.83 for medical facts. With the gradient boosting tree as our best performing model, we analyzed the strength of individual features in predicting one's social support need. Among other discoveries, we found that users seeking emotional support tend to post more in OHSNs compared with others. We developed an initial framework for automatically predicting social support needs in OHSNs using survey data. Future work should involve nonsurvey

  20. Structural characteristics of the online social networks of maltreated youth and offline sexual risk behavior.

    Science.gov (United States)

    Negriff, Sonya; Valente, Thomas W

    2018-02-07

    Maltreated youth are at risk for exposure to online sexual content and high-risk sexual behavior, yet characteristics of their online social networks have not been examined as a potential source of vulnerability. The aims of the current study were: 1) to test indicators of size (number of friends) and fragmentation (number of connections between friends) of maltreated young adults' online networks as predictors of intentional and unintentional exposure to sexual content and offline high-risk sexual behavior and 2) to test maltreatment as a moderator of these associations. Participants were selected from a longitudinal study on the effects of child maltreatment (n = 152; Mean age 21.84 years). Data downloaded from Facebook were used to calculate network variables of size (number of friends), density (connections between friends), average degree (average number of connections for each friend), and percent isolates (those not connected to others in the network). Self-reports of intentional and unintentional exposure to online sexual content and offline high-risk sexual behavior were the outcome variables. Multiple-group path modeling showed that only for the maltreated group having a higher percent of isolates in the network predicted intentional exposure to online sexual content and offline high-risk sexual behavior. An implication of this finding is that the composition of the Facebook network may be used as a risk indicator for individuals with child-welfare documented maltreatment experiences. Copyright © 2018. Published by Elsevier Ltd.

  1. Gender differences in collaborative learning over online social networks: Epistemological beliefs and behaviors

    Directory of Open Access Journals (Sweden)

    Rosanna Y.-Y. Chan

    2013-09-01

    Full Text Available Online social networks are popular venues for computer-supported collaborative work and computer-supported collaborative learning. Professionals within the same discipline, such as software developers, often interact over various social network sites for knowledge updates and collective understandings. The current study aims at gathering empirical evidences concerning gender differences in online social network beliefs and behaviors. A total of 53 engineering postgraduate students were engaged in a blogging community for collaborative learning. Participants’ beliefs about collaboration and nature of knowledge and knowing (i.e. epistemological beliefs are investigated. More specifically, social network analysis metrics including in-degree, out-degree, closeness centrality, and betweenness centrality are obtained from an 8-interval longitudinal SNA. Methodologically speaking, the current work puts forward mixed methods of longitudinal SNA and quantitative beliefs survey to explore online social network participants’ beliefs and behaviors. The study’s findings demonstrate significant gender differences in collaborative learning through online social networks, including (1 female engineering postgraduate students engage significantly more actively in online communications, (2 male engineering postgraduate students are more likely to be the potential controllers of information flows, and (3 gender differences exist in belief gains related to social aspects, but not individual's epistemic aspects. Overall, participants in both genders demonstrated enhanced beliefs in collaboration as well as the nature of knowledge and knowing.

  2. Multi-Stratum Networks: toward a unified model of on-line identities

    DEFF Research Database (Denmark)

    Rossi, Luca; Magnani, Matteo

    2012-01-01

    One of the reasons behind the success of Social Network Analysis is its simple and general graph model made of nodes (representing individuals) and ties. However, when we focus on our daily on-line experience we must confront a more complex scenario: people inhabitate several on-line spaces...... interacting to several communities active on various technological infrastructures like Twitter, Facebook, YouTube or FourSquare and with distinct social objectives. This constitutes a complex network of interconnected networks where users' identities are spread and where information propagates navigating...

  3. Online Social Networking, Sexual Risk and Protective Behaviors: Considerations for Clinicians and Researchers.

    Science.gov (United States)

    Holloway, Ian W; Dunlap, Shannon; Del Pino, Homero E; Hermanstyne, Keith; Pulsipher, Craig; Landovitz, Raphael J

    2014-09-01

    Online social networking refers to the use of internet-based technologies that facilitate connection and communication between users. These platforms may be accessed via computer or mobile device (e.g., tablet, smartphone); communication between users may include linking of profiles, posting of text, photo and video content, instant messaging and email. This review provides an overview of recent research on the relationship between online social networking and sexual risk and protective behaviors with a focus on use of social networking sites (SNS) among young people and populations at high risk for sexually transmitted infections (STIs). While findings are mixed, the widespread use of SNS for sexual communication and partner seeking presents opportunities for the delivery and evaluation of public health interventions. Results of SNS-based interventions to reduce sexual risk are synthesized in order to offer hands-on advice for clinicians and researchers interested in engaging patients and study participants via online social networking.

  4. Habit as a moderator and exogenous predictor of social networks: The case of online social networking

    Directory of Open Access Journals (Sweden)

    Akwesi Assensoh-Kodua

    2015-10-01

    Full Text Available This paper tests the factors likely to impact continuance intentions through the medium of online social networks (OSN for business transactions. The expectation-confirmation theory (ECT from the consumer behaviour literature is made use of; to forward a set of theories that validate a prior model from IS usage research. Eight research hypotheses, after a field survey of OSNs participants for business transactions were conducted are empirically validated. 300 useable responses from LinkedIn and Twitter social networking platforms users for business transactions were analysed with the WarpPLS 4.0 bootstrapping technique. The study results provide significant evidence in support of perceived trust and user satisfaction, as determinants of the continuance intention of people using OSN platforms for business transactions. Above all, the research model was tested for the moderating effects of usage habit, which was found to impact relationships between continuance intention and perceived trust, resulting in an improved predictive capability of (R2=0.55 as compared to base model of (R2=0.52. The moderating result indicates that a higher level of habit increases the effect of perceived trust on continuance intention

  5. Recommendations for the design, implementation and evaluation of social support in online communities, networks, and groups.

    Science.gov (United States)

    Weiss, Jacob B; Berner, Eta S; Johnson, Kevin B; Giuse, Dario A; Murphy, Barbara A; Lorenzi, Nancy M

    2013-12-01

    A new model of health care is emerging in which individuals can take charge of their health by connecting to online communities and social networks for personalized support and collective knowledge. Web 2.0 technologies expand the traditional notion of online support groups into a broad and evolving range of informational, emotional, as well as community-based concepts of support. In order to apply these technologies to patient-centered care, it is necessary to incorporate more inclusive conceptual frameworks of social support and community-based research methodologies. This paper introduces a conceptualization of online social support, reviews current challenges in online support research, and outlines six recommendations for the design, evaluation, and implementation of social support in online communities, networks, and groups. The six recommendations are illustrated by CanConnect, an online community for cancer survivors in middle Tennessee. These recommendations address the interdependencies between online and real-world support and emphasize an inclusive framework of interpersonal and community-based support. The applications of these six recommendations are illustrated through a discussion of online support for cancer survivors. Copyright © 2013 Elsevier Inc. All rights reserved.

  6. An online neural network triggering system for the Tile Calorimeter

    CERN Document Server

    Damazio, D O; Magacho, P V

    2002-01-01

    For the hadronic calorimeter of ATLAS, TileCal, neural processing is used to establish an efficient methodology for the online particle identification in beam tests of calorimeter prototypes. Although beam purity is usually very good for a selected particle type, background from wrong-type particles cannot be avoided and is routinely identified in the offline analysis. The proposed neural system is trained online to identify electrons, pions, and muons at different energy levels and it achieves more than 90% efficiency in terms of particle identification. The neural system is being implemented by integrating it to the readout drive (ROD) of the TileCal. (12 refs).

  7. Analysing Health Professionals' Learning Interactions in an Online Social Network: A Longitudinal Study.

    Science.gov (United States)

    Li, Xin; Verspoor, Karin; Gray, Kathleen; Barnett, Stephen

    2016-01-01

    This paper summarises a longitudinal analysis of learning interactions occurring over three years among health professionals in an online social network. The study employs the techniques of Social Network Analysis (SNA) and statistical modeling to identify the changes in patterns of interaction over time and test associated structural network effects. SNA results indicate overall low participation in the network, although some participants became active over time and even led discussions. In particular, the analysis has shown that a change of lead contributor results in a change in learning interaction and network structure. The analysis of structural network effects demonstrates that the interaction dynamics slow down over time, indicating that interactions in the network are more stable. The health professionals may be reluctant to share knowledge and collaborate in groups but were interested in building personal learning networks or simply seeking information.

  8. Tweacher: New proposal for Online Social Networks Impact in Secondary Education

    Directory of Open Access Journals (Sweden)

    Sebastián ROMERO

    2013-05-01

    Full Text Available This paper presents and analyzes the potential uses and motivations of online social networks in education, with special emphasis on secondary education. First, we show several previous researches supporting the use of social networking as an educational tool and discuss Edmodo, an educative online social network. The work carried out during two academic years with senior students of primary and secondary schools is also analyzed. After that we present Tweacher an educative social network application and evaluate its use in the classroom to prove its useful use between teachers and students. This research has allowed us to see the reality of social network use among young people and identify the challenges of its application to education environment.

  9. On-line Configuration of Network Emulator for Intelligent Energy System Testbed Applications

    DEFF Research Database (Denmark)

    Kemal, Mohammed Seifu; Iov, Florin; Olsen, Rasmus Løvenstein

    2015-01-01

    a mechanism for on-line configuration and monitoring of heterogeneous communication technologies implemented at smart energy system testbed of Aal-borg university. It proposes a model with three main components, a network emulator used to emulate the communication scenarios using KauNet, graphical user...... interface for visualizing, configuring and monitoring of the emulated scenarios and a network socket linking the graphic server and network emulation server on-line. Specifically, our focus area is to build a model that gives us ability to look at some of the challenges on implementing inter......Intelligent energy networks (or Smart Grids) provide efficient solutions for a grid integrated with near-real-time communication technologies between various grid assets in power generation, transmission and distribution systems. The design of a communication network associated with intelligent...

  10. Developing an online professional network for veterinary education: the NOVICE project.

    Science.gov (United States)

    Baillie, Sarah; Kinnison, Tierney; Forrest, Neil; Dale, Vicki H M; Ehlers, Jan P; Koch, Michael; Mándoki, Mira; Ciobotaru, Emilia; de Groot, Esther; Boerboom, Tobias B B; van Beukelen, Peter

    2011-01-01

    An online professional network for veterinarians, veterinary students, veterinary educationalists, and ICT (Information and Communication Technology) educationalists is being developed under the EU (European Union) Lifelong Learning Programme. The network uses Web 2.0, a term used to describe the new, more interactive version of the Internet, and includes tools such as wikis, blogs, and discussion boards. Focus groups conducted with qualified and student veterinarians within the project's five founding countries (The Netherlands, Germany, United Kingdom, Hungary, Romania) demonstrated that online professional communities can be valuable for accessing information and establishing contacts. Online networks have the potential to overcome common challenges to face-to-face communities-such as distance, cost, and timing-but they have their own drawbacks, such as security and professionalism issues. The Network Of Veterinary ICt in Education (NOVICE) was developed using Elgg, an open-source, free social networking platform, after several software options had been considered. NOVICE aims to promote the understanding of Web 2.0, confidence to use social software tools, and participation in an online community. Therefore, the Web site contains help sections, Frequently Asked Questions, and access to support from ICT experts. Five months after the network's launch (and just over one year into the project) 515 members from 28 countries had registered. Further research will include analysis of a core group's activities, which will inform ongoing support for and development of informal, lifelong learning in a veterinary context.

  11. Do online social media cut through the constraints that limit the size of offline social networks?

    Science.gov (United States)

    Dunbar, R I M

    2016-01-01

    The social brain hypothesis has suggested that natural social network sizes may have a characteristic size in humans. This is determined in part by cognitive constraints and in part by the time costs of servicing relationships. Online social networking offers the potential to break through the glass ceiling imposed by at least the second of these, potentially enabling us to maintain much larger social networks. This is tested using two separate UK surveys, each randomly stratified by age, gender and regional population size. The data show that the size and range of online egocentric social networks, indexed as the number of Facebook friends, is similar to that of offline face-to-face networks. For one sample, respondents also specified the number of individuals in the inner layers of their network (formally identified as support clique and sympathy group), and these were also similar in size to those observed in offline networks. This suggests that, as originally proposed by the social brain hypothesis, there is a cognitive constraint on the size of social networks that even the communication advantages of online media are unable to overcome. In practical terms, it may reflect the fact that real (as opposed to casual) relationships require at least occasional face-to-face interaction to maintain them.

  12. CouchSurfing : experiences, reputation, references and decision-making in an online hospitality network

    OpenAIRE

    Franz, Melanie

    2014-01-01

    The aim of this thesis was to analyse behavioural patterns that occur after a negative experience during a hospitality exchange. The focus of this study is the largest online hospitality network to date, the CouchSurfing Project. CouchSurfing enables travellers to connect and to offer each other help in form of a free hospitality exchange. Furthermore, CouchSurfing presents a platform for cultural exchange and the possibility for members to connect in this online-offline community. As part...

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

    DEFF Research Database (Denmark)

    Hillmann, Robert; Trier, Matthias

    2012-01-01

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

  14. Online Social Networks: Essays on Membership, Privacy, and Structure

    NARCIS (Netherlands)

    Hofstra, B.

    2017-01-01

    The structure of social networks is crucial for obtaining social support, for meaningful connections to unknown social groups, and to overcome prejudice. Yet, we know little about the structure of social networks beyond those contacts that stand closest to us. This lack of knowledge results from a

  15. Towards a Social Networks Model for Online Learning & Performance

    Science.gov (United States)

    Chung, Kon Shing Kenneth; Paredes, Walter Christian

    2015-01-01

    In this study, we develop a theoretical model to investigate the association between social network properties, "content richness" (CR) in academic learning discourse, and performance. CR is the extent to which one contributes content that is meaningful, insightful and constructive to aid learning and by social network properties we…

  16. Towards benchmarking citizen observatories: Features and functioning of online amateur weather networks.

    Science.gov (United States)

    Gharesifard, Mohammad; Wehn, Uta; van der Zaag, Pieter

    2017-05-15

    Crowd-sourced environmental observations are increasingly being considered as having the potential to enhance the spatial and temporal resolution of current data streams from terrestrial and areal sensors. The rapid diffusion of ICTs during the past decades has facilitated the process of data collection and sharing by the general public and has resulted in the formation of various online environmental citizen observatory networks. Online amateur weather networks are a particular example of such ICT-mediated observatories that are rooted in one of the oldest and most widely practiced citizen science activities, namely amateur weather observation. The objective of this paper is to introduce a conceptual framework that enables a systematic review of the features and functioning of these expanding networks. This is done by considering distinct dimensions, namely the geographic scope and types of participants, the network's establishment mechanism, revenue stream(s), existing communication paradigm, efforts required by data sharers, support offered by platform providers, and issues such as data accessibility, availability and quality. An in-depth understanding of these dimensions helps to analyze various dynamics such as interactions between different stakeholders, motivations to run the networks, and their sustainability. This framework is then utilized to perform a critical review of six existing online amateur weather networks based on publicly available data. The main findings of this analysis suggest that: (1) there are several key stakeholders such as emergency services and local authorities that are not (yet) engaged in these networks; (2) the revenue stream(s) of online amateur weather networks is one of the least discussed but arguably most important dimensions that is crucial for the sustainability of these networks; and (3) all of the networks included in this study have one or more explicit modes of bi-directional communication, however, this is limited to

  17. Composite Behavioral Modeling for Identity Theft Detection in Online Social Networks

    OpenAIRE

    Wang, Cheng; Yang, Bo

    2018-01-01

    In this work, we aim at building a bridge from poor behavioral data to an effective, quick-response, and robust behavior model for online identity theft detection. We concentrate on this issue in online social networks (OSNs) where users usually have composite behavioral records, consisting of multi-dimensional low-quality data, e.g., offline check-ins and online user generated content (UGC). As an insightful result, we find that there is a complementary effect among different dimensions of r...

  18. Craving Facebook? Behavioral addiction to online social networking and its association with emotion regulation deficits.

    Science.gov (United States)

    Hormes, Julia M; Kearns, Brianna; Timko, C Alix

    2014-12-01

    To assess disordered online social networking use via modified diagnostic criteria for substance dependence, and to examine its association with difficulties with emotion regulation and substance use. Cross-sectional survey study targeting undergraduate students. Associations between disordered online social networking use, internet addiction, deficits in emotion regulation and alcohol use problems were examined using univariate and multivariate analyses of covariance. A large University in the Northeastern United States. Undergraduate students (n = 253, 62.8% female, 60.9% white, age mean = 19.68, standard deviation = 2.85), largely representative of the target population. The response rate was 100%. Disordered online social networking use, determined via modified measures of alcohol abuse and dependence, including DSM-IV-TR diagnostic criteria for alcohol dependence, the Penn Alcohol Craving Scale and the Cut-down, Annoyed, Guilt, Eye-opener (CAGE) screen, along with the Young Internet Addiction Test, Alcohol Use Disorders Identification Test, Acceptance and Action Questionnaire-II, White Bear Suppression Inventory and Difficulties in Emotion Regulation Scale. Disordered online social networking use was present in 9.7% [n = 23; 95% confidence interval (5.9, 13.4)] of the sample surveyed, and significantly and positively associated with scores on the Young Internet Addiction Test (P addictive. Modified measures of substance abuse and dependence are suitable in assessing disordered online social networking use. Disordered online social networking use seems to arise as part of a cluster of symptoms of poor emotion regulation skills and heightened susceptibility to both substance and non-substance addiction. © 2014 Society for the Study of Addiction.

  19. Integration of Online Parameter Identification and Neural Network for In-Flight Adaptive Control

    Science.gov (United States)

    Hageman, Jacob J.; Smith, Mark S.; Stachowiak, Susan

    2003-01-01

    An indirect adaptive system has been constructed for robust control of an aircraft with uncertain aerodynamic characteristics. This system consists of a multilayer perceptron pre-trained neural network, online stability and control derivative identification, a dynamic cell structure online learning neural network, and a model following control system based on the stochastic optimal feedforward and feedback technique. The pre-trained neural network and model following control system have been flight-tested, but the online parameter identification and online learning neural network are new additions used for in-flight adaptation of the control system model. A description of the modification and integration of these two stand-alone software packages into the complete system in preparation for initial flight tests is presented. Open-loop results using both simulation and flight data, as well as closed-loop performance of the complete system in a nonlinear, six-degree-of-freedom, flight validated simulation, are analyzed. Results show that this online learning system, in contrast to the nonlearning system, has the ability to adapt to changes in aerodynamic characteristics in a real-time, closed-loop, piloted simulation, resulting in improved flying qualities.

  20. Peer influences: the impact of online and offline friendship networks on adolescent smoking and alcohol use.

    Science.gov (United States)

    Huang, Grace C; Unger, Jennifer B; Soto, Daniel; Fujimoto, Kayo; Pentz, Mary Ann; Jordan-Marsh, Maryalice; Valente, Thomas W

    2014-05-01

    Online social networking sites (SNSs) have become a popular mode of communication among adolescents. However, little is known about the effects of social online activity on health behaviors. The authors examined the use of SNSs among friends and the degree to which SNS activities relate to face-to-face peer influences and adolescent risk behaviors. Longitudinal egocentric friendship network data along with adolescent social media use and risk behaviors were collected from 1,563 10th-grade students across five Southern California high schools. Measures of online and offline peer influences were computed and assessed using fixed-effects models. The frequency of adolescent SNS use and the number of their closest friends on the same SNSs were not significantly associated with risk behaviors. However, exposure to friends' online pictures of partying or drinking was significantly associated with both smoking (β = .11, p effects on risk behaviors. Exposure to risky online content had a direct impact on adolescents' risk behaviors and significantly interacted with risk behaviors of their friends. These results provide evidence that friends' online behaviors should be considered a viable source of peer influence and that increased efforts should focus on educating adolescents on the negative effects of risky online displays. Copyright © 2014 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.

  1. Online fouling detection in electrical circulation heaters using neural networks

    Energy Technology Data Exchange (ETDEWEB)

    Lalot, S. [M.E.T.I.E.R., Longuenesse Cedex (France); Universite de Valenciennes (France). LME; Lecoeuche, S. [M.E.T.I.E.R., Longuenesse Cedex (France); Universite de Lille (France). Laboratoire 13D

    2003-06-01

    Here is presented a method that is able to detect fouling during the service of a circulation electrical heater. The neural based technique is divided in two major steps: identification and classification. Each step uses a neural network, the connection weights of the first one being the inputs of the second network. Each step is detailed and the main characteristics and abilities of the two neural networks are given. It is shown that the method is able to discriminate fouling from viscosity modification that would lead to the same type of effect on the total heat transfer coefficient. (author)

  2. On-line identification of hybrid systems using an adaptive growing and pruning RBF neural network

    DEFF Research Database (Denmark)

    Alizadeh, Tohid

    2008-01-01

    This paper introduces an adaptive growing and pruning radial basis function (GAP-RBF) neural network for on-line identification of hybrid systems. The main idea is to identify a global nonlinear model that can predict the continuous outputs of hybrid systems. In the proposed approach, GAP......-RBF neural network uses a modified unscented kalman filter (UKF) with forgetting factor scheme as the required on-line learning algorithm. The effectiveness of the resulting identification approach is tested and evaluated on a simulated benchmark hybrid system....

  3. Disseminating Innovations in Teaching Value-Based Care Through an Online Learning Network.

    Science.gov (United States)

    Gupta, Reshma; Shah, Neel T; Moriates, Christopher; Wallingford, September; Arora, Vineet M

    2017-08-01

    A national imperative to provide value-based care requires new strategies to teach clinicians about high-value care. We developed a virtual online learning network aimed at disseminating emerging strategies in teaching value-based care. The online Teaching Value in Health Care Learning Network includes monthly webinars that feature selected innovators, online discussion forums, and a repository for sharing tools. The learning network comprises clinician-educators and health system leaders across North America. We conducted a cross-sectional online survey of all webinar presenters and the active members of the network, and we assessed program feasibility. Six months after the program launched, there were 277 learning community members in 22 US states. Of the 74 active members, 50 (68%) completed the evaluation. Active members represented independently practicing physicians and trainees in 7 specialties, nurses, educators, and health system leaders. Nearly all speakers reported that the learning network provided them with a unique opportunity to connect with a different audience and achieve greater recognition for their work. Of the members who were active in the learning network, most reported that strategies gleaned from the network were helpful, and some adopted or adapted these innovations at their home institutions. One year after the program launched, the learning network had grown to 364 total members. The learning network helped participants share and implement innovations to promote high-value care. The model can help disseminate innovations in emerging areas of health care transformation, and is sustainable without ongoing support after a period of start-up funding.

  4. Limitation of degree information for analyzing the interaction evolution in online social networks

    Science.gov (United States)

    Shang, Ke-Ke; Yan, Wei-Sheng; Xu, Xiao-Ke

    2014-04-01

    Previously many studies on online social networks simply analyze the static topology in which the friend relationship once established, then the links and nodes will not disappear, but this kind of static topology may not accurately reflect temporal interactions on online social services. In this study, we define four types of users and interactions in the interaction (dynamic) network. We found that active, disappeared, new and super nodes (users) have obviously different strength distribution properties and this result also can be revealed by the degree characteristics of the unweighted interaction and friendship (static) networks. However, the active, disappeared, new and super links (interactions) only can be reflected by the strength distribution in the weighted interaction network. This result indicates the limitation of the static topology data on analyzing social network evolutions. In addition, our study uncovers the approximately stable statistics for the dynamic social network in which there are a large variation for users and interaction intensity. Our findings not only verify the correctness of our definitions, but also helped to study the customer churn and evaluate the commercial value of valuable customers in online social networks.

  5. A context-sensitive trust model for online social networking

    CSIR Research Space (South Africa)

    Danny, MN

    2016-11-01

    Full Text Available In Social Networking Sites (SNSs), users tend to accept friend requests and share their personal information based on intuitive trust levels. Mistakenly trusting and sharing private information with malicious users may lead to a wide variety...

  6. Studying User Footprints in Different Online Social Networks

    OpenAIRE

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

    2013-01-01

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

  7. Dimensions and dynamics of citizen observatories: The case of online amateur weather networks

    Science.gov (United States)

    Gharesifard, Mohammad; Wehn, Uta; van der Zaag, Pieter

    2016-04-01

    Crowd-sourced environmental observations are being increasingly considered as having the potential to enhance the spatial and temporal resolution of current data streams from terrestrial and areal sensors. The rapid diffusion of ICTs during the past decades has facilitated the process of data collection and sharing by the general public (so-called citizen science) and has resulted in the formation of various online environmental citizen observatory networks. Online amateur weather networks are a particular example of such ICT-mediated citizen observatories as one of the oldest and most widely practiced citizen science activities. The objective of this paper is to introduce a conceptual framework that enables a systematic review of different dimensions of these mushrooming/expanding networks. These dimensions include the geographic scope and types of network participants; the network's establishment mechanism, revenue stream(s) and existing communication paradigm; efforts required by citizens and support offered by platform providers; and issues such as data accessibility, availability and quality. An in-depth understanding of these dimensions helps to analyze various dynamics such as interactions between different stakeholders, motivations to run these networks, sustainability of the platforms, data ownership and level of transparency of each network. This framework is then utilized to perform a critical and normative review of six existing online amateur weather networks based on publicly available data. The main findings of this analysis suggest that: (1) There are several key stakeholders such as emergency services and local authorities that are not (yet) engaged in these networks. (2) The revenue stream(s) of online amateur weather networks is one of the least discussed but most important dimensions that is crucial for the sustainability of these networks. (3) Although all of the networks included in this study have one or more explicit pattern of two

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

    Science.gov (United States)

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

    2017-11-01

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

  9. Human-Centered Development of an Online Social Network for Metabolic Syndrome Management.

    Science.gov (United States)

    Núñez-Nava, Jefersson; Orozco-Sánchez, Paola A; López, Diego M; Ceron, Jesus D; Alvarez-Rosero, Rosa E

    2016-01-01

    According to the International Diabetes Federation (IDF), a quarter of the world's population has Metabolic Syndrome (MS). To develop (and assess the users' degree of satisfaction of) an online social network for patients who suffer from Metabolic Syndrome, based on the recommendations and requirements of the Human-Centered Design. Following the recommendations of the ISO 9241-210 for Human-Centered Design (HCD), an online social network was designed to promote physical activity and healthy nutrition. In order to guarantee the active participation of the users during the development of the social network, a survey, an in-depth interview, a focal group, and usability tests were carried out with people suffering from MS. The study demonstrated how the different activities, recommendations, and requirements of the ISO 9241-210 are integrated into a traditional software development process. Early usability tests demonstrated that the user's acceptance and the effectiveness and efficiency of the social network are satisfactory.

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

    Science.gov (United States)

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

    2013-12-01

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

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

    Science.gov (United States)

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

    2012-11-01

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

  12. Online Social Networks for Crowdsourced Multimedia-Involved Behavioral Testing: An Empirical Study

    OpenAIRE

    Choi, Jun-Ho; Lee, Jong-Seok

    2016-01-01

    Online social networks have emerged as effective crowdsourcing media to recruit participants in recent days. However, issues regarding how to effectively exploit them have not been adequately addressed yet. In this paper, we investigate the reliability and effectiveness of multimedia-involved behavioral testing via social network-based crowdsourcing, especially focused on Facebook as a medium to recruit participants. We conduct a crowdsourcing-based experiment for a music recommendation probl...

  13. Making "social" safer: are Facebook and other online networks becoming less hazardous for health professionals?

    Science.gov (United States)

    George, Daniel R

    2012-01-01

    Major concerns about privacy have limited health professionals' usage of popular social networking sites such as Facebook. However, the landscape of social media is changing in favor of more sophisticated privacy controls that enable users to more carefully manage public and private information. This evolution in technology makes it potentially less hazardous for health professionals to consider accepting colleagues and patients into their online networks, and invites medicine to think constructively about how social media may add value to contemporary healthcare.

  14. Online solving of economic dispatch problem using neural network approach and comparing it with classical method

    International Nuclear Information System (INIS)

    Mohammadi, A.; Varahram, M.H.

    2007-01-01

    In this study, two methods for solving economic dispatch problems, namely Hopfield neural network and lambda iteration method are compared. Three sample of power system with 3, 6 and 20 units have been considered. The time required for CPU, for solving economic dispatch of these two systems has been calculated. It has been Shown that for on-line economic dispatch, Hopfield neural network is more efficient and the time required for Convergence is considerably smaller compared to classical methods. (author)

  15. Online and in-person networking among women in the Earth Sciences Women's Network at www.ESWNonline.org

    Science.gov (United States)

    Kontak, R.; Adams, A. S.; De Boer, A. M.; Hastings, M. G.; Holloway, T.; Marin-Spiotta, E.; Steiner, A. L.; Wiedinmyer, C.

    2012-12-01

    The Earth Science Women's Network is an international peer-mentoring network of women in the Earth Sciences, many of whom are in the early stages of their careers. Membership is free and has grown through "word of mouth," and includes upper-level undergraduates, graduate students, professionals in a range of environmental fields, scientists working in public and private institutions. Our mission is to promote career development, build community, provide informal mentoring and support, and facilitate professional collaborations. Since 2002 we have accomplished this trough online networking, including over email and a listserv, on facebook, in-person networking events, and professional development workshops. Now in our 10th year, ESWN is debuting a new web-center that creates an online space exclusively for women in any discipline of the Earth (including planetary) sciences. ESWN members can connect and create an online community of support and encouragement for themselves as women in a demanding career. Many women in Earth Science fields feel isolated and are often the only woman in their department or work environments. ESWN is a place to meet others, discuss issues faced in creating work-life balance and professional success and share best practices through peer mentoring. Now on ESWN's new web-center, members can create and personalize their profiles and search for others in their field, nearby, or with similar interests. Online discussions in the members-only area can also be searched. Members can create groups for discussion or collaboration, with document sharing and password protection. Publicly, we can share gained knowledge with a broader audience, like lessons learned at our professional development workshops and collected recommendations from members. The new web center allows for more connectivity among other online platforms used by our members, including linked-in, facebook, and twitter. Built in Wordpress with a Buddpress members-only section, the new

  16. The world of e-patients: A content analysis of online social networks focusing on diseases.

    Science.gov (United States)

    Orizio, Grazia; Schulz, Peter; Gasparotti, Cinzia; Caimi, Luigi; Gelatti, Umberto

    2010-12-01

    as the participatory Web developed to create virtual worlds and communities, health institutions and activists discovered Web 2.0 tools, in particular the creation of health-related online social networks. To analyze the existing online social networks dedicated to health issues, we performed an active search on the Internet for such Web sites and analyzed their features according to the content analysis method. the study was performed in September and October 2009. We analyzed a sample of health social networks for patients, selected using four common search engines. A codebook was elaborated to investigate four areas: general information; technical characteristics and utilities; characteristics of the Web site and contents, both general and related to the online community. the search led to a sample of 41 social networks. Twenty-three Web sites (56.1%) were dedicated to several diseases, the others to one only. Although the majority of the sample (87.8%) provided a way to contact the Web site, only five (12.2%) showed the name of the author or operating organization. Eight Web sites (19.5%) indicated one or more sponsors, and nine (22.0%) named one or more partners. It was often hard to tell whether an institution mentioned was a sponsor or a partner. Five Web sites (12.2%) enabled users to buy health-related products online. Twelve Web sites (29.3%) offered users the chance to search for doctors, and 12 (29.3%) gave therapeutic information. Two Web sites (4.9%) published aggregate statistical data about the patients registered with the social network. the data reveal the high heterogeneity of health-related social networks and raise interesting considerations on such controversial topics as the quality of online health information, research perspectives, interactivity, and empowerment. In particular, our findings are relevant to criticism regarding the openness and transparency of these Web sites, the use of personal data, and privacy issues.

  17. Development and comparison of neural network based soft sensors for online estimation of cement clinker quality.

    Science.gov (United States)

    Pani, Ajaya Kumar; Vadlamudi, Vamsi Krishna; Mohanta, Hare Krishna

    2013-01-01

    The online estimation of process outputs mostly related to quality, as opposed to their belated measurement by means of hardware measuring devices and laboratory analysis, represents the most valuable feature of soft sensors. As of now there have been very few attempts for soft sensing of cement clinker quality which is mostly done by offline laboratory analysis resulting at times in low quality clinker. In the present work three different neural network based soft sensors have been developed for online estimation of cement clinker properties. Different input and output data for a rotary cement kiln were collected from a cement plant producing 10,000 tons of clinker per day. The raw data were pre-processed to remove the outliers and the resulting missing data were imputed. The processed data were then used to develop a back propagation neural network model, a radial basis network model and a regression network model to estimate the clinker quality online. A comparison of the estimation capabilities of the three models has been done by simulation of the developed models. It was observed that radial basis network model produced better estimation capabilities than the back propagation and regression network models. Copyright © 2012 ISA. Published by Elsevier Ltd. All rights reserved.

  18. An information search model for online social Networks - MOBIRSE

    OpenAIRE

    Miguel Angel Niño Zambrano; Iván Darío Cerón Moreno; Jhon Alberto Astaiza Perafán; Gustavo Adolfo Ramírez

    2015-01-01

    En los últimos años las Redes Sociales Online (RSO) han venido cobrando gran importancia entre los usuarios de Internet, puesto que son sitios donde se puede conocer personas, publicar y compartir contenidos de una manera fácil y gratuita. Esto ha provocado que el volumen de información contenida en estos sitios web crezca de manera exponencial. Por lo tanto, la búsqueda web se convierte en una herramienta importante para que los usuarios puedan encontrar fácilmente la información relevante p...

  19. The Influence of Social Networks on the Adolescents’ Online Practices

    OpenAIRE

    García Jiménez, Antonio; López de Ayala López, María Cruz; Catalina García, Beatriz

    2013-01-01

    Profundizar en los cambios que se están perfilando en los hábitos on-line de los adolescentes, en particular debido a la fuerte irrupción de las redes sociales en su vida cotidiana, así como en las implicaciones socioculturales de estos procesos, es el objeto de este trabajo. La metodología de investigación se centró en un cuestionario autoadministrado aplicado a escala nacional. Sobre una muestra representativa nacional de 2.077 adolescentes (de 12 a 17 años), se ha buscado actua...

  20. Frequency of victimization experiences and well-being among online, offline and combined victims on social online network sites of German children and adolescents

    Directory of Open Access Journals (Sweden)

    Michael eGlüer

    2015-12-01

    Full Text Available Victimization is associated with negative developmental outcomes in childhood and adolescence. However, previous studies have provided mixed results regarding the association between offline and online victimization and indicators of social, psychological, and somatic well-being. In this study, we investigated 1,906 German children and adolescents (grades 5 to 10, mean age = 13.9; SD = 2.1 with and without offline or online victimization experiences who participated in a social online network (SNS. Online questionnaires were used to assess previous victimization (offline, online, combined, and without, somatic and psychological symptoms, self-esteem, and social self-concept (social competence, resistance to peer influence, esteem by others. In total, 1,362 (71.4% children and adolescents reported being a member of at least one social online network, and 377 students (28.8% reported previous victimization. Most children and adolescents had offline victimization experiences (17.5%, whereas 2.7% reported online victimization, and 8.6% reported combined experiences. Girls reported more online and combined victimization, and boys reported more offline victimization. The type of victimization (offline, online, combined was associated with increased reports of psychological and somatic symptoms, lower self-esteem and esteem by others, and lower resistance to peer influences. The effects were comparable for the groups with offline and online victimization. They were, however, increased in the combined group in comparison to victims with offline experiences alone.

  1. Technology use and reasons to participate in online social networking websites for people living with HIV in the US

    Science.gov (United States)

    Horvath, Keith J.; Danilenko, Gene P.; Williams, Mark L.; Simoni, Jane; Amico, K. Rivet; Oakes, J. Michael; Rosser, B.R. Simon

    2012-01-01

    It is unknown if online social networking technologies are already highly integrated among some people living with HIV (PLWH) or have yet to be adopted. To fill this gap in understanding, 312 PLWH (84% male, 69% white) residing in the US completed on online survey in 2009 of their patterns of social networking and mobile phone use. Twenty-two persons also participated in one of two online focus groups. Results showed that 76% of participants with lower adherence to HIV medication used social networking websites/features at least once a week. Their ideal online social networking health websites included one that facilitated socializing with others (45% of participants) and relevant informational content (22%), although privacy was a barrier to use (26%). Texting (81%), and to a lesser extent mobile web-access (51%), was widely used among participants. Results support the potential reach of online social networking and text messaging intervention approaches. PMID:22350832

  2. Analysis of Online Social Networks to Understand Information Sharing Behaviors Through Social Cognitive Theory

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Hong-Jun [ORNL; Tourassi, Georgia [ORNL

    2014-01-01

    Analyzing the contents of online social networks is an effective process for monitoring and understanding peoples behaviors. Since the nature of conversation and information propagation is similar to traditional conversation and learning, one of the popular socio-cognitive methods, social cognitive theory was applied to online social networks to. Two major news topics about colon cancer were chosen to monitor traffic of Twitter messages. The activity of leaders on the issue (i.e., news companies or people will prior Twitter activity on topics related to colon cancer) was monitored. In addition, the activity of followers , people who never discussed the topics before, but replied to the discussions was also monitored. Topics that produce tangible benefits such as positive outcomes from appropriate preventive actions received dramatically more attention and online social media traffic. Such characteristics can be explained with social cognitive theory and thus present opportunities for effective health campaigns.

  3. Analysis of Online Social Networks to Understand Information Sharing Behaviors Through Social Cognitive Theory.

    Science.gov (United States)

    Yoon, Hong-Jun; Tourassi, Georgia

    2014-05-01

    Analyzing the contents of online social networks is an effective process for monitoring and understanding peoples' behaviors. Since the nature of conversation and information propagation is similar to traditional conversation and learning, one of the popular socio-cognitive methods, social cognitive theory was applied to online social networks to. Two major news topics about colon cancer were chosen to monitor traffic of Twitter messages. The activity of "leaders" on the issue (i.e., news companies or people will prior Twitter activity on topics related to colon cancer) was monitored. In addition, the activity of "followers", people who never discussed the topics before, but replied to the discussions was also monitored. Topics that produce tangible benefits such as positive outcomes from appropriate preventive actions received dramatically more attention and online social media traffic. Such characteristics can be explained with social cognitive theory and thus present opportunities for effective health campaigns.

  4. An Online Social Networking Approach to Reinforce Learning of Rocks and Minerals

    Science.gov (United States)

    Kennelly, Patrick

    2009-01-01

    Numerous and varied methods are used in introductory Earth science and geology classes to help students learn about rocks and minerals, such as classroom lectures, laboratory specimen identification, and field trips. This paper reports on a method using online social networking. The choice of this forum was based on two criteria. First, many…

  5. Social Capital, Self-Esteem, and Use of Online Social Network Sites: A Longitudinal Analysis

    Science.gov (United States)

    Steinfield, Charles; Ellison, Nicole B.; Lampe, Cliff

    2008-01-01

    A longitudinal analysis of panel data from users of a popular online social network site, Facebook, investigated the relationship between intensity of Facebook use, measures of psychological well-being, and bridging social capital. Two surveys conducted a year apart at a large U.S. university, complemented with in-depth interviews with 18 Facebook…

  6. Getting acquainted through social networking sites: Testing a model of online uncertainty reduction and social attraction

    NARCIS (Netherlands)

    Antheunis, M.L.; Valkenburg, P.M.; Peter, J.

    2008-01-01

    The first aim of this study was to examine which uncertainty reduction strategies members of social networking sites used to gain information about a person who they had recently met online. The second aim was to investigate whether and how these uncertainty reduction strategies resulted in social

  7. Usefulness of Social Network Sites for Adolescents' Development of Online Career Skills

    NARCIS (Netherlands)

    Rutten, Mariëlle; Ros, Anje; Kuijpers, Marinka; Kreijns, Karel

    2018-01-01

    Schools have an important role in teaching students how to use Social Network Site (SNS) for career purposes. This involves the opportunity for students to practice online career skills. Different types of digital environments are available for schools. There are SNS designed to enable users to

  8. Online Professional Learning Networks: A Viable Solution to the Professional Development Dilemma

    Science.gov (United States)

    Cook, Rebecca J.; Jones-Bromenshenkel, Melissa; Huisinga, Shawn; Mullins, Frank

    2017-01-01

    Quality professional development must meet the demands and needs of the person engaging in the activity. However, many opportunities for special educators are often less than optimal in terms of timeliness, expertise, or applicability. This article describes the idea of online professional learning networks (PLNs) which allow for collaboration and…

  9. Literacy and Capital in Immigrant Youths' Online Networks across Countries

    Science.gov (United States)

    Lam, Wan Shun Eva

    2014-01-01

    Communication technologies are playing an increasingly prominent role in facilitating immigrants' social networks across countries and the transnational positioning of immigrant youth in their online language and literacy practices. Drawing from a comparative case study of the digital literacy practices of immigrant youth of Chinese descent,…

  10. 75 FR 71376 - Simplified Network Application Processing System, On-Line Registration and Account Maintenance

    Science.gov (United States)

    2010-11-23

    ...-02] RIN 0694-AE98 Simplified Network Application Processing System, On-Line Registration and Account... account to submit license applications and similar documents electronically. The current registration... parties would have with respect to keeping information in their accounts current. DATES: Comments must be...

  11. A Theoretical Framework for Building Online Communities of Practice with Social Networking Tools

    Science.gov (United States)

    Gunawardena, Charlotte N.; Hermans, Mary Beth; Sanchez, Damien; Richmond, Carol; Bohley, Maribeth; Tuttle, Rebekah

    2009-01-01

    This paper proposes a theoretical framework as a foundation for building online communities of practice when a suite of social networking applications referred to as collective intelligence tools are utilized to develop a product or solutions to a problem. Drawing on recent developments in Web 2.0 tools, research on communities of practice and…

  12. The Use of Online Social Networks by Polish Former Erasmus Students: A Large-Scale Survey

    Science.gov (United States)

    Bryla, Pawel

    2014-01-01

    There is an increasing role of online social networks in the life of young Poles. We conducted a large-scale survey among Polish former Erasmus students. We have received 2450 completed questionnaires from alumni of 115 higher education institutions all over Poland. 85.4% of our respondents reported they kept in touch with their former Erasmus…

  13. Understanding the Online Information-Seeking Behaviours of Young People: The Role of Networks of Support

    Science.gov (United States)

    Eynon, R.; Malmberg, L.-E.

    2012-01-01

    Information seeking is one of the most popular online activities for young people and can provide an additional information channel, which may enhance learning. In this study, we propose and test a model that adds to the existing literature by examining the ways in which parents, schools, and friends (what we call networks of support) effect young…

  14. The social sharing of emotion (SSE) in online social networks: a case study in Live Journal

    NARCIS (Netherlands)

    Rodriguez Hidalgo, C.T.; Tan, E.S.H.; Verlegh, P.W.J.

    2015-01-01

    Social Sharing of Emotion (SSE) occurs when one person shares an emotional experience with another and is considered potentially beneficial. Though social sharing has been shown prevalent in interpersonal communication, research on its occurrence and communication structure in online social networks

  15. Online Social Network Dependency Pada Digital Immigrant Pengguna Path Di Jakarta

    OpenAIRE

    Tanring, Vini

    2014-01-01

    Tujuan penelitian ini untuk mengetahui bagaimana Online Social Network (OSN) Dependency pada Digital Immigrant pengguna Path di Jakarta. Indikator yang digunakan untuk mengukur OSN Dependency yaitu Generalized Problematic Internet Use Scale (GPIUS), terdiri dari mood alternation, social benefit, negative outcome, compulsivity, excessive time, withdrawal, dan interpersonal control. Hasil penelitian menunjukkan bahwa OSN Dependency pada Digital Immigrant pengguna Path merupakan hal yang tidak ...

  16. Online Social Networks and Computer Skills of University Students

    Science.gov (United States)

    Barbas, Maria Potes; Valerio, Gabriel; Rodríguez-Martínez, María del Carmen; Herrera-Murillo, Dagoberto José; Belmonte-Jiménez, Ana María

    2014-01-01

    Currently a large number of college students belong to social networks and spend several hours a week on them. Some sectors of society, like parents and teachers, are concerned about the negative impact on their academic work and in their personal lives. However, because the potential positive impacts have not been explored enough, this research…

  17. Professionalism in Student Online Social Networking: The Role of Educators

    Science.gov (United States)

    Chester, A.; Kienhuis, M.; Pisani, H.; Shahwan-Akl, L.; White, K.

    2013-01-01

    Social media now form a common part of university students' experience. Both at university and after graduation, in their personal and professional lives, social media offer opportunities for connection previously unavailable. The ubiquitous nature of social networking has brought with it professional and ethical issues that need to be…

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

    Czech Academy of Sciences Publication Activity Database

    Slanina, František

    2014-01-01

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

  19. Network Biology (http://www.iaees.org/publications/journals/nb/online-version.asp

    Directory of Open Access Journals (Sweden)

    networkbiology@iaees.org

    Full Text Available Network Biology ISSN 2220-8879 URL: http://www.iaees.org/publications/journals/nb/online-version.asp RSS: http://www.iaees.org/publications/journals/nb/rss.xml E-mail: networkbiology@iaees.org Editor-in-Chief: WenJun Zhang Aims and Scope NETWORK BIOLOGY (ISSN 2220-8879; CODEN NBEICS is an open access, peer-reviewed international journal that considers scientific articles in all different areas of network biology. It is the transactions of the International Society of Network Biology. It dedicates to the latest advances in network biology. The goal of this journal is to keep a record of the state-of-the-art research and promote the research work in these fast moving areas. The topics to be covered by Network Biology include, but are not limited to: •Theories, algorithms and programs of network analysis •Innovations and applications of biological networks •Ecological networks, food webs and natural equilibrium •Co-evolution, co-extinction, biodiversity conservation •Metabolic networks, protein-protein interaction networks, biochemical reaction networks, gene networks, transcriptional regulatory networks, cell cycle networks, phylogenetic networks, network motifs •Physiological networksNetwork regulation of metabolic processes, human diseases and ecological systems •Social networks, epidemiological networks •System complexity, self-organized systems, emergence of biological systems, agent-based modeling, individual-based modeling, neural network modeling, and other network-based modeling, etc. We are also interested in short communications that clearly address a specific issue or completely present a new ecological network, food web, or metabolic or gene network, etc. Authors can submit their works to the email box of this journal, networkbiology@iaees.org. All manuscripts submitted to this journal must be previously unpublished and may not be considered for publication elsewhere at any time during review period of this journal

  20. An Online Life Like Any Other: Identity, Self-Determination, and Social Networking Among Adults with Intellectual Disabilities.

    Science.gov (United States)

    Chadwick, Darren D; Fullwood, Chris

    2018-01-01

    Research focusing on online identity and the personal experiences of adults with intellectual disabilities (ID) is currently limited. Eleven adults with ID were interviewed regarding personal experiences of being online and using social media. Data were analyzed qualitatively using thematic network analysis. Two global themes, online relatedness and sharing and online agency and support, highlighted the positive potential of social media in enabling the development and maintenance of social bonds, valued social roles, and feelings of enjoyment, competence, autonomy, and self-worth. Participants reported sharing various expressed online identities that did not focus on or hide impairment, challenging notions of dependency, with participants both providing support and being supported online.

  1. On-line validation of feedwater flow rate in nuclear power plants using neural networks

    International Nuclear Information System (INIS)

    Khadem, M.; Ipakchi, A.; Alexandro, F.J.; Colley, R.W.

    1994-01-01

    On-line calibration of feedwater flow rate measurement in nuclear power plants provides a continuous realistic value of feedwater flow rate. It also reduces the manpower required for periodic calibration needed due to the fouling and defouling of the venturi meter surface condition. This paper presents a method for on-line validation of feedwater flow rate in nuclear power plants. The method is an improvement of the previously developed method which is based on the use of a set of process variables dynamically related to the feedwater flow rate. The online measurements of this set of variables are used as inputs to a neural network to obtain an estimate of the feedwater flow rate reading. The difference between the on-line feedwater flow rate reading, and the neural network estimate establishes whether there is a need to apply a correction factor to the feedwater flow rate measurement for calculation of the actual reactor power. The method was applied to the feedwater flow meters in the two feedwater flow loops of the TMI-1 nuclear power plant. The venturi meters used for flow measurements are susceptible to frequent fouling that degrades their measurement accuracy. The fouling effects can cause an inaccuracy of up to 3% relative error in feedwater flow rate reading. A neural network, whose inputs were the readings of a set of reference instruments, was designed to predict both feedwater flow rates simultaneously. A multi-layer feedforward neural network employing the backpropagation algorithm was used. A number of neural network training tests were performed to obtain an optimum filtering technique of the input/output data of the neural networks. The result of the selection of the filtering technique was confirmed by numerous Fast Fourier Transform (FFT) tests. Training and testing were done on data from TMI-1 nuclear power plant. The results show that the neural network can predict the correct flow rates with an absolute relative error of less than 2%

  2. Engineering Online and In-Person Social Networks for Physical Activity: A Randomized Trial.

    Science.gov (United States)

    Rovniak, Liza S; Kong, Lan; Hovell, Melbourne F; Ding, Ding; Sallis, James F; Ray, Chester A; Kraschnewski, Jennifer L; Matthews, Stephen A; Kiser, Elizabeth; Chinchilli, Vernon M; George, Daniel R; Sciamanna, Christopher N

    2016-12-01

    Social networks can influence physical activity, but little is known about how best to engineer online and in-person social networks to increase activity. The purpose of this study was to conduct a randomized trial based on the Social Networks for Activity Promotion model to assess the incremental contributions of different procedures for building social networks on objectively measured outcomes. Physically inactive adults (n = 308, age, 50.3 (SD = 8.3) years, 38.3 % male, 83.4 % overweight/obese) were randomized to one of three groups. The Promotion group evaluated the effects of weekly emailed tips emphasizing social network interactions for walking (e.g., encouragement, informational support); the Activity group evaluated the incremental effect of adding an evidence-based online fitness walking intervention to the weekly tips; and the Social Networks group evaluated the additional incremental effect of providing access to an online networking site for walking as well as prompting walking/activity across diverse settings. The primary outcome was mean change in accelerometer-measured moderate-to-vigorous physical activity (MVPA), assessed at 3 and 9 months from baseline. Participants increased their MVPA by 21.0 min/week, 95 % CI [5.9, 36.1], p = .005, at 3 months, and this change was sustained at 9 months, with no between-group differences. Although the structure of procedures for targeting social networks varied across intervention groups, the functional effect of these procedures on physical activity was similar. Future research should evaluate if more powerful reinforcers improve the effects of social network interventions. The trial was registered with the ClinicalTrials.gov (NCT01142804).

  3. The Relationship Between Use of Social Network Sites, Online Social Support, and Well-Being

    Science.gov (United States)

    2017-01-01

    Abstract. Existing work on the effects of social network sites (SNS) on well-being has often stressed that SNS can help people gain social support from their online networks, which positively affects their well-being. However, the majority of studies in this area have been cross-sectional in nature and/or relied on student samples. Using data from six waves of a longitudinal study with a representative sample of Dutch Internet users, we first examined whether users and nonusers of SNS differ in online social support and well-being (as indicated by life satisfaction and stress). In a second step, we investigated in more detail how SNS use – more specifically, asking for advice and the number of strong ties on these SNS – are related to online social support, stress, and satisfaction with life. Overall, our results provide no evidence for SNS use and online social support affecting either stress or life satisfaction. SNS users reported more online social support than nonusers did, but also higher levels of stress; the two groups did not differ in overall life satisfaction. With regard to the underlying processes, we found positive cross-sectional and longitudinal relationships between asking for advice on SNS and online social support, indicating that SNS can be an effective tool for receiving social support. However, online social support was not related to higher life satisfaction or reduced stress 6 months later; instead, it seems that SNS users with lower life satisfaction and/or higher stress seek more social support online by asking for advice on SNS. PMID:29147141

  4. Diffusion Dynamics of Energy Saving Practices in Large Heterogeneous Online Networks.

    Science.gov (United States)

    Mohammadi, Neda; Wang, Qi; Taylor, John E

    2016-01-01

    Online social networks are today's fastest growing communications channel and a popular source of information for many, so understanding their contribution to building awareness and shaping public perceptions of climate change is of utmost importance. Today's online social networks are composed of complex combinations of entities and communication channels and it is not clear which communicators are the most influential, what the patterns of communication flow are, or even whether the widely accepted two-step flow of communication model applies in this new arena. This study examines the diffusion of energy saving practices in a large online social network across organizations, opinion leaders, and the public by tracking 108,771 communications on energy saving practices among 1,084 communicators, then analyzing the flow of information and influence over a 28 day period. Our findings suggest that diffusion networks of messages advocating energy saving practices are predominantly led by the activities of dedicated organizations but their attempts do not result in substantial public awareness, as most of these communications are effectively trapped in organizational loops in which messages are simply shared between organizations. Despite their comparably significant influential values, opinion leaders played a weak role in diffusing energy saving practices to a wider audience. Thus, the two-step flow of communication model does not appear to describe the sharing of energy conservation practices in large online heterogeneous networks. These results shed new light on the underlying mechanisms driving the diffusion of important societal issues such as energy efficiency, particularly in the context of large online social media outlets.

  5. Diffusion Dynamics of Energy Saving Practices in Large Heterogeneous Online Networks.

    Directory of Open Access Journals (Sweden)

    Neda Mohammadi

    Full Text Available Online social networks are today's fastest growing communications channel and a popular source of information for many, so understanding their contribution to building awareness and shaping public perceptions of climate change is of utmost importance. Today's online social networks are composed of complex combinations of entities and communication channels and it is not clear which communicators are the most influential, what the patterns of communication flow are, or even whether the widely accepted two-step flow of communication model applies in this new arena. This study examines the diffusion of energy saving practices in a large online social network across organizations, opinion leaders, and the public by tracking 108,771 communications on energy saving practices among 1,084 communicators, then analyzing the flow of information and influence over a 28 day period. Our findings suggest that diffusion networks of messages advocating energy saving practices are predominantly led by the activities of dedicated organizations but their attempts do not result in substantial public awareness, as most of these communications are effectively trapped in organizational loops in which messages are simply shared between organizations. Despite their comparably significant influential values, opinion leaders played a weak role in diffusing energy saving practices to a wider audience. Thus, the two-step flow of communication model does not appear to describe the sharing of energy conservation practices in large online heterogeneous networks. These results shed new light on the underlying mechanisms driving the diffusion of important societal issues such as energy efficiency, particularly in the context of large online social media outlets.

  6. School Absenteeism: An Online Survey via Social Networks.

    Science.gov (United States)

    Pflug, Verena; Schneider, Silvia

    2016-06-01

    School absenteeism is a significant social and public health problem. However, existing prevalence rates are often not representative due to biased assessment processes at schools. The present study assessed school absenteeism in Germany using a nationwide online self-report survey. Although our definition of school absenteeism was more conservative than in previous studies, nearly 9 % of the 1359 high school students reported school absenteeism within the past 7 days. Absent students lived less often with both parents, were on average of lower socioeconomic status, and reported more emotional problems, behavioral problems and less prosocial behavior than attending students. Being an indicator of a wide variety of problems in children and adolescents, school absenteeism deserves much more attention. Future directions for research and implications for prevention and intervention programs are discussed.

  7. Diffusion of influence in energy awareness campaigns on the online social networking site of facebook

    Energy Technology Data Exchange (ETDEWEB)

    Samaha, Kimberly

    2010-09-15

    The era of government jurisdiction based on separate and autonomous entities has been replaced with an intergovernmental and intersectoral network of industry, regulators, special interest groups and individual citizens. New forms of regulatory feedback will be inspired more by the concepts of networks- they will be flatter, leaner, and more flexible. An evaluation of new methods for the diffusion of public awareness regarding energy technologies, policies and projects, was conducted using the technology platform of Facebook. This paper reports on the results of an eighteen month formal study of the Diffusion of Influence in Online Social Networks.

  8. Exploring mobile health in a private online social network.

    Science.gov (United States)

    Memon, Qurban A; Mustafa, Asma Fayes

    2015-01-01

    Health information is very vulnerable. Certain individuals or corporate organisations will continue to steal it similar to bank account data once data is on wireless channels. Once health information is part of a social network, corresponding privacy issues also surface. Insufficiently trained employees at hospitals that pay less attention to creating a privacy-aware culture will suffer loss when mobile devices containing health information are lost, stolen or sniffed. In this work, a social network system is explored as a m-health system from a privacy perspective. A model is developed within a framework of data-driven privacy and implemented on Android operating system. In order to check feasibility of the proposed model, a prototype application is developed on Facebook for different services, including: i) sharing user location; ii) showing nearby friends; iii) calculating and sharing distance moved, and calories burned; iv) calculating, tracking and sharing user heart rate; etc.

  9. DEVELOPMENT AND EVALUATION OF NING SOCIAL NETWORK FOR TEACHING TRAINING ONLINE SURVEILLANCE

    Directory of Open Access Journals (Sweden)

    Ezad Azraai JAMSARI (Corresponding Author

    2013-01-01

    Full Text Available Supervision of teaching practice is an important aspect of training teachers in improving their teaching skills. Barriers such as distance and time factor are the constraints faced by the lecturers at the National University of Malaysia to communicate with the teacher trainees under their supervision. Therefore, this study aims to develop and evaluate a social-networking site Ning's platform for the supervision of lecturers to teach on-line training. This study used the case design where a total of nine teacher trainees involved in this study. It found that overall, acceptance of the use of the social-networking site Ning mean score at the highest level of 3.91. In addition, all student teachers have positive attitudes towards the use of the social-networking site Ning social-networking site and agree a suitable approach to the supervision of one of the online teaching practices. While the “blog” is the most active facility used by student teachers in which they do self-reflection. In conclusion, the social-networking site Ning has the potential to assist lecturers to carry out supervision on-line teaching practice.

  10. Integrated on-line plant monitoring system for HTTR using neural networks

    International Nuclear Information System (INIS)

    Nabeshima, Kunihiko; Subekti, Muhammad; Matsuishi, Tomomi; Makino, Jun; Ohno, Tomio; Kudo, Kazuhiko; Nakagawa, Shigeaki

    2007-01-01

    The neural networks have been utilized in on-line monitoring-system of High Temperature Engineering Tested Reactor (HTTR) with thermal power of 30 MW. In this system, several neural networks can independently model the plant dynamics with different architecture, input and output signals and learning algorithm. Monitoring task of each neural network is also different, respectively. Those parallel method applications require distributed architecture of computer network for performing real-time tasks. One of main task is real-time monitoring by Multi-Layer Perceptron (MLP) in auto-associative mode, which can model and estimate the whole plant dynamics by training normal operational data only. The basic principle of the anomaly detection is to monitor the difference between process signals measured from the actual plant and the corresponding values estimated by MLP. Other tasks are on-line reactivity prediction, reactivity and helium leak monitoring, respectively. From the on-line test results, each neural network shows good prediction and reliable detection performances. (author)

  11. Integrated on-line plant monitoring system for HTTR with neural networks

    International Nuclear Information System (INIS)

    Nabeshima, Kunihiko; Nakagawa, Shigeaki; Subekti, Muhammad; Matsuishi, Tomomi; Ohno, Tomio; Kudo, Kazuhiko

    2008-01-01

    The neural networks have been utilized in on-line monitoring-system of High Temperature Engineering Tested Reactor (HTTR) with thermal power of 30 MW. In this system, several neural networks can independently model the plant dynamics with different architecture, input and output signals and learning algorithm. Monitoring task of each neural network is also different, respectively. Those parallel method applications require distributed architecture of computer network for performing real-time tasks. One of main task is real-time plant monitoring by Multi-Layer Perceptron (MLP) in auto-associative mode, which can model and estimate the whole plant dynamics by training normal operational data only. The basic principle of the anomaly detection is to monitor the difference between process signals measured from the actual plant and the corresponding values estimated by MLP. Other tasks are on-line reactivity prediction, reactivity and helium leak monitoring, respectively. From the on-line monitoring results at the safety demonstration tests, each neural network shows good prediction and reliable detection performances. (author)

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

    Science.gov (United States)

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

    2014-11-01

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

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

    Science.gov (United States)

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

    2014-06-16

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

  14. Offline constraints in online drug marketplaces: An exploratory analysis of a cryptomarket trade network.

    Science.gov (United States)

    Norbutas, Lukas

    2018-04-02

    Cryptomarkets, or illegal anonymizing online platforms that facilitate drug trade, have been analyzed in a rapidly growing body of research. Previous research has found that, despite increased risks, cryptomarket sellers are often willing to ship illegal drugs internationally. There is little to no information, however, about the extent to which uncertainty and risk related to geographic constraints shapes buyers' behavior and, in turn, the structure of the global online drug trade network. In this paper, we analyze the structure of a complete cryptomarket trade network with a focus on the role of geographic clustering of buyers and sellers. We use publicly available crawls of the cryptomarket Abraxas, encompassing market transactions between 463 sellers and 3542 buyers of drugs in 2015. We use descriptive social network analysis and Exponential Random Graph Models (ERGM) to analyze the structure of the trade network. The structure of the online drug trade network is primarily shaped by geographical boundaries. Buyers are more likely to buy from multiple sellers within a single country, and avoid buying from sellers in different countries, which leads to strong geographic clustering. The effect is especially strong between continents and weaker for countries within Europe. A small fraction of buyers (10%) account for more than a half of all drug purchases, while most buyers only buy once. Online drug trade networks might still be heavily shaped by offline (geographic) constraints, despite their ability to provide access for end-users to large international supply. Cryptomarkets might be more "localized" and less international than thought before. We discuss potential explanations for such geographical clustering and implications of the findings. Copyright © 2018 The Author(s). Published by Elsevier B.V. All rights reserved.

  15. Professional conduct among registered nurses in the use of online social networking sites.

    Science.gov (United States)

    Levati, Sara

    2014-10-01

    To explore the use of Facebook by Registered Nurses (RNs) in Italy and the United Kingdom (UK), focusing on the disclosure of personal and professional information. The use of online social network sites among medical students and doctors is posing new ethical challenges to the profession. To date, little research has explored the use of online social networking sites among nurses. A cross-national survey. Data were assessed on 124 nurses' profile pages, readily available without viewing restrictions. Content analysis and inferential statistics were undertaken to describe usage and identify similarities and differences between the two country-groups of nurses. Data were collected between December 2011-January 2012. Overall, UK and Italian RNs showed a similar use of the online platform, tending to disclose personal pictures, home town and current home location, as well as updates and comments related to personal and work-related activities. A statistically significant higher proportion of nurses in Italy disclosed their sexual orientation. In both groups, a few cases were observed of potentially unprofessional content in relation to the use of alcohol, nudity and material of a salacious nature. Although most of the UK and Italy RNs appear to be aware of the risks posed by their online exposure, their online activity indicates the blurring of their personal and professional lives; this is posing new ethical, legal and professional challenges to members of the nursing profession. Further research and debate is encouraged at national and international level. © 2014 John Wiley & Sons Ltd.

  16. The Method of Building a Network of Online Showcases on the Basis of the MVC Architecture

    Directory of Open Access Journals (Sweden)

    Pursky Oleg I.

    2017-10-01

    Full Text Available A method to build a network of online showcases that support a large number of customer orders and visits, which meets the current performance standards and the reliability of Internet solutions in the sphere electronic commerce, has been developed. The method involves the creation of a typical showcase and the implementation for the information management system of a showcases network of an own database operating on the data from the central management information system with the two-way data replication. A mechanism for «cloning» the online showcases, which are part of the network, and their quick integration with the business processes of enterprise and a management system based on a typical showcase, has been proposed. The development of typical online showcases is implemented on the basis of MVC concept (Model-View-Controller, the ASP.NET MVC Framework Technology, and the visual templates of web pages, thus ensuring that the algorithms for the behavior of objects are independent of both the objects themselves and their visual representation. This enhances the development of e-commerce projects significantly, speeds up the implementation process, and provides a high degree of flexibility and functionality of the online showcases.

  17. Online Self-Organizing Network Control with Time Averaged Weighted Throughput Objective

    Directory of Open Access Journals (Sweden)

    Zhicong Zhang

    2018-01-01

    Full Text Available We study an online multisource multisink queueing network control problem characterized with self-organizing network structure and self-organizing job routing. We decompose the self-organizing queueing network control problem into a series of interrelated Markov Decision Processes and construct a control decision model for them based on the coupled reinforcement learning (RL architecture. To maximize the mean time averaged weighted throughput of the jobs through the network, we propose a reinforcement learning algorithm with time averaged reward to deal with the control decision model and obtain a control policy integrating the jobs routing selection strategy and the jobs sequencing strategy. Computational experiments verify the learning ability and the effectiveness of the proposed reinforcement learning algorithm applied in the investigated self-organizing network control problem.

  18. From Subjective Trust to Objective Trustworthiness in On-line Social Networks: Overview and Challenges

    OpenAIRE

    David Zejda

    2010-01-01

    Nowadays dozens of people share their content in the current Web 2.0 space, talk with friends in social networking sites such as Facebook and live on the Net in many other ways. They do all this quite naturally, forgetting the healthy cautiousness sometimes. In real life we rely on trusted people. Do we know how to reflect real-world trust mechanisms into on-line social software? In the article we focused to bring overview on state of the art in main ideas behind a trust processing in online ...

  19. Understanding the Context of Learning in an Online Social Network for Health Professionals' Informal Learning.

    Science.gov (United States)

    Li, Xin; Gray, Kathleen; Verspoor, Karin; Barnett, Stephen

    2017-01-01

    Online social networks (OSN) enable health professionals to learn informally, for example by sharing medical knowledge, or discussing practice management challenges and clinical issues. Understanding the learning context in OSN is necessary to get a complete picture of the learning process, in order to better support this type of learning. This study proposes critical contextual factors for understanding the learning context in OSN for health professionals, and demonstrates how these contextual factors can be used to analyse the learning context in a designated online learning environment for health professionals.

  20. Are health behavior change interventions that use online social networks effective? A systematic review.

    Science.gov (United States)

    Maher, Carol A; Lewis, Lucy K; Ferrar, Katia; Marshall, Simon; De Bourdeaudhuij, Ilse; Vandelanotte, Corneel

    2014-02-14

    The dramatic growth of Web 2.0 technologies and online social networks offers immense potential for the delivery of health behavior change campaigns. However, it is currently unclear how online social networks may best be harnessed to achieve health behavior change. The intent of the study was to systematically review the current level of evidence regarding the effectiveness of online social network health behavior interventions. Eight databases (Scopus, CINAHL, Medline, ProQuest, EMBASE, PsycINFO, Cochrane, Web of Science and Communication & Mass Media Complete) were searched from 2000 to present using a comprehensive search strategy. Study eligibility criteria were based on the PICOS format, where "population" included child or adult populations, including healthy and disease populations; "intervention" involved behavior change interventions targeting key modifiable health behaviors (tobacco and alcohol consumption, dietary intake, physical activity, and sedentary behavior) delivered either wholly or in part using online social networks; "comparator" was either a control group or within subject in the case of pre-post study designs; "outcomes" included health behavior change and closely related variables (such as theorized mediators of health behavior change, eg, self-efficacy); and "study design" included experimental studies reported in full-length peer-reviewed sources. Reports of intervention effectiveness were summarized and effect sizes (Cohen's d and 95% confidence intervals) were calculated wherever possible. Attrition (percentage of people who completed the study), engagement (actual usage), and fidelity (actual usage/intended usage) with the social networking component of the interventions were scrutinized. A total of 2040 studies were identified from the database searches following removal of duplicates, of which 10 met inclusion criteria. The studies involved a total of 113,988 participants (ranging from n=10 to n=107,907). Interventions included

  1. Modeling the cooperative and competitive contagions in online social networks

    Science.gov (United States)

    Zhuang, Yun-Bei; Chen, J. J.; Li, Zhi-hong

    2017-10-01

    The wide adoption of social media has increased the interaction among different pieces of information, and this interaction includes cooperation and competition for our finite attention. While previous research focus on fully competition, this paper extends the interaction to be both "cooperation" and "competition", by employing an IS1S2 R model. To explore how two different pieces of information interact with each other, the IS1S2 R model splits the agents into four parts-(Ignorant-Spreader I-Spreader II-Stifler), based on SIR epidemic spreading model. Using real data from Weibo.com, a social network site similar to Twitter, we find some parameters, like decaying rates, can both influence the cooperative diffusion process and the competitive process, while other parameters, like infectious rates only have influence on the competitive diffusion process. Besides, the parameters' effect are more significant in the competitive diffusion than in the cooperative diffusion.

  2. Theoretical approaches of online social network interventions and implications for behavioral change: a systematic review.

    Science.gov (United States)

    Arguel, Amaël; Perez-Concha, Oscar; Li, Simon Y W; Lau, Annie Y S

    2018-02-01

    The aim of this review was to identify general theoretical frameworks used in online social network interventions for behavioral change. To address this research question, a PRISMA-compliant systematic review was conducted. A systematic review (PROSPERO registration number CRD42014007555) was conducted using 3 electronic databases (PsycINFO, Pubmed, and Embase). Four reviewers screened 1788 abstracts. 15 studies were selected according to the eligibility criteria. Randomized controlled trials and controlled studies were assessed using Cochrane Collaboration's "risk-of-bias" tool, and narrative synthesis. Five eligible articles used the social cognitive theory as a framework to develop interventions targeting behavioral change. Other theoretical frameworks were related to the dynamics of social networks, intention models, and community engagement theories. Only one of the studies selected in the review mentioned a well-known theory from the field of health psychology. Conclusions were that guidelines are lacking in the design of online social network interventions for behavioral change. Existing theories and models from health psychology that are traditionally used for in situ behavioral change should be considered when designing online social network interventions in a health care setting. © 2016 John Wiley & Sons, Ltd.

  3. EXPLORING THE RELATIONSHIPS AMONG SOCIAL BENEFITS, ONLINE SOCIAL NETWORK DEPENDENCY, SATISFACTION, AND YOUTH’S HABIT FORMATION

    Directory of Open Access Journals (Sweden)

    Tran Van Dat

    2015-12-01

    Full Text Available Online social network is one of the biggest Internet phenomenon, which has attracted the interest of many marketers and psychologists who wanted to understand social network users’ behavior. Recognizing the lack of theoretical and empirical attention that has been given to this field, especially in Vietnam market, this study was conducted to examine the relationships among social benefits, online social network dependency, satisfaction, and youth’s habit formation in the context of Facebook. The findings of the study of 200 Facebook users indicated that the interrelationship among four factors of social benefits, online social network dependency, satisfaction, and habit formation affect each other. Indeed, dependency on online social network among the youth whose age ranged from 16 to 24 years old is significantly affected by social benefits factor and leads to the formation of habit. In addition, satisfaction plays a role in determining habitual Facebook use. This paper discusses theoretical and practical implication in marketing and psychology field.

  4. Methods for inferring health-related social networks among coworkers from online communication patterns.

    Science.gov (United States)

    Matthews, Luke J; DeWan, Peter; Rula, Elizabeth Y

    2013-01-01

    Studies of social networks, mapped using self-reported contacts, have demonstrated the strong influence of social connections on the propensity for individuals to adopt or maintain healthy behaviors and on their likelihood to adopt health risks such as obesity. Social network analysis may prove useful for businesses and organizations that wish to improve the health of their populations by identifying key network positions. Health traits have been shown to correlate across friendship ties, but evaluating network effects in large coworker populations presents the challenge of obtaining sufficiently comprehensive network data. The purpose of this study was to evaluate methods for using online communication data to generate comprehensive network maps that reproduce the health-associated properties of an offline social network. In this study, we examined three techniques for inferring social relationships from email traffic data in an employee population using thresholds based on: (1) the absolute number of emails exchanged, (2) logistic regression probability of an offline relationship, and (3) the highest ranked email exchange partners. As a model of the offline social network in the same population, a network map was created using social ties reported in a survey instrument. The email networks were evaluated based on the proportion of survey ties captured, comparisons of common network metrics, and autocorrelation of body mass index (BMI) across social ties. Results demonstrated that logistic regression predicted the greatest proportion of offline social ties, thresholding on number of emails exchanged produced the best match to offline network metrics, and ranked email partners demonstrated the strongest autocorrelation of BMI. Since each method had unique strengths, researchers should choose a method based on the aspects of offline behavior of interest. Ranked email partners may be particularly useful for purposes related to health traits in a social network.

  5. Digital divide 2.0: the role of social networking sites in seeking health information online from a longitudinal perspective.

    Science.gov (United States)

    Feng, Yang; Xie, Wenjing

    2015-01-01

    Adopting a longitudinal angle, this study analyzed data from the Pew Internet's Health Tracking Survey in 2006, 2008, and 2010 to identify potential communication inequalities in social networking site use. Results showed that with the growing role of social networking site use in predicting people's likelihood of seeking health information online, the socioeconomic and demographic factors that contributed to the disparities in social networking site use could also lead to disparities in seeking health information online. Also, results indicated that people are more likely to seek heath-related information online if they or their close family or friends have a chronic disease situation.

  6. Severe Accident Management System On-line Network SAMSON

    International Nuclear Information System (INIS)

    Silverman, Eugene B.

    2004-01-01

    SAMSON is a computational tool used by accident managers in the Technical Support Centers (TSC) and Emergency Operations Facilities (EOF) in the event of a nuclear power plant accident. SAMSON examines over 150 status points monitored by nuclear power plant process computers during a severe accident and makes predictions about when core damage, support plate failure, and reactor vessel failure will occur. These predictions are based on the current state of the plant assuming that all safety equipment not already operating will fail. SAMSON uses expert systems, as well as neural networks trained with the back propagation learning algorithms to make predictions. Training on data from an accident analysis code (MAAP - Modular Accident Analysis Program) allows SAMSON to associate different states in the plant with different times to critical failures. The accidents currently recognized by SAMSON include steam generator tube ruptures (SGTRs), with breaks ranging from one tube to eight tubes, and loss of coolant accidents (LOCAs), with breaks ranging from 0.0014 square feet (1.30 cm 2 ) in size to breaks 3.0 square feet in size (2800 cm 2 ). (author)

  7. The responsible use of online social networking: who should mentor medical students.

    Science.gov (United States)

    Patel, Pradip D; Roberts, John L; Miller, Karen Hughes; Ziegler, Craig; Ostapchuk, Michael

    2012-01-01

    As medical students become more active in online social networking (OSN), there are increasing concerns regarding violations of patient privacy and a lack of professionalism. Students need to be mentored, but who is best suited to the task? We hypothesized that residents are closer to students in usage and attitudes toward online communication than are faculty. If so, they would be more credible as mentors. We surveyed faculty (N = 16), 1st-year residents (N = 120), and 3rd-year medical students (N = 130) to compare attitudes about OSN and the online usage patterns. We found residents to be more like students in usage patterns of personal electronic media and in their choice of the mentoring techniques that should be used. Residents say they were not prepared to mentor students without additional guidance but were more confident than faculty members that they had the knowledge to do so.

  8. Online Distributed Learning Over Networks in RKH Spaces Using Random Fourier Features

    Science.gov (United States)

    Bouboulis, Pantelis; Chouvardas, Symeon; Theodoridis, Sergios

    2018-04-01

    We present a novel diffusion scheme for online kernel-based learning over networks. So far, a major drawback of any online learning algorithm, operating in a reproducing kernel Hilbert space (RKHS), is the need for updating a growing number of parameters as time iterations evolve. Besides complexity, this leads to an increased need of communication resources, in a distributed setting. In contrast, the proposed method approximates the solution as a fixed-size vector (of larger dimension than the input space) using Random Fourier Features. This paves the way to use standard linear combine-then-adapt techniques. To the best of our knowledge, this is the first time that a complete protocol for distributed online learning in RKHS is presented. Conditions for asymptotic convergence and boundness of the networkwise regret are also provided. The simulated tests illustrate the performance of the proposed scheme.

  9. Original research: online social networking patterns among adolescents, young adults, and sexual offenders.

    Science.gov (United States)

    Dowdell, Elizabeth B; Burgess, Ann W; Flores, J Robert

    2011-07-01

    The use of online social networks like Facebook continues to increase rapidly among all age groups and segments of our society, presenting new opportunities for the exchange of sexual information as well as for potentially unsafe encounters between predators and the vulnerable or young. This study surveyed middle school, high school, and college-age students, as well as sexual offenders, regarding their use of social networking sites in order to provide information to better focus education and prevention efforts from nurses and other health care providers. Written questionnaires asking about various characteristics of participants' use of social networking sites were distributed to each group and filled out by 404 middle school students, 2,077 high school students, 1,284 students drawn from five traditional four-year colleges, and 466 adults who had committed either an Internet sexual offense or a hands-on sexual offense (in some cases both). Notable findings emerging from our analysis of the questionnaire responses included the following: offenders and students both frequent social networking sites, although at the time of the study offenders reported that they preferred Myspace and students that they preferred Facebook; nearly two-thirds of the Internet offenders said they'd initiated the topic of sex in their first chat session; more than half of the Internet offenders disguised their identity when online; most Internet offenders we surveyed said they preferred communicating with teenage girls rather than teenage boys; high school students' experience with "sexting" (sharing nude photos of themselves or others on cell phones or online) differed significantly according to their sex; a small number of students are being threatened and assaulted by people they meet online; avatar sites such as Second Life were used both by students and offenders, with both child molesters and Internet offenders expressing interest in Second Life. The use of the Internet presents

  10. Emergence of scale-free close-knit friendship structure in online social networks.

    Science.gov (United States)

    Cui, Ai-Xiang; Zhang, Zi-Ke; Tang, Ming; Hui, Pak Ming; Fu, Yan

    2012-01-01

    Although the structural properties of online social networks have attracted much attention, the properties of the close-knit friendship structures remain an important question. Here, we mainly focus on how these mesoscale structures are affected by the local and global structural properties. Analyzing the data of four large-scale online social networks reveals several common structural properties. It is found that not only the local structures given by the indegree, outdegree, and reciprocal degree distributions follow a similar scaling behavior, the mesoscale structures represented by the distributions of close-knit friendship structures also exhibit a similar scaling law. The degree correlation is very weak over a wide range of the degrees. We propose a simple directed network model that captures the observed properties. The model incorporates two mechanisms: reciprocation and preferential attachment. Through rate equation analysis of our model, the local-scale and mesoscale structural properties are derived. In the local-scale, the same scaling behavior of indegree and outdegree distributions stems from indegree and outdegree of nodes both growing as the same function of the introduction time, and the reciprocal degree distribution also shows the same power-law due to the linear relationship between the reciprocal degree and in/outdegree of nodes. In the mesoscale, the distributions of four closed triples representing close-knit friendship structures are found to exhibit identical power-laws, a behavior attributed to the negligible degree correlations. Intriguingly, all the power-law exponents of the distributions in the local-scale and mesoscale depend only on one global parameter, the mean in/outdegree, while both the mean in/outdegree and the reciprocity together determine the ratio of the reciprocal degree of a node to its in/outdegree. Structural properties of numerical simulated networks are analyzed and compared with each of the four real networks. This

  11. Adaptive online inverse control of a shape memory alloy wire actuator using a dynamic neural network

    International Nuclear Information System (INIS)

    Mai, Huanhuan; Liao, Xiaofeng; Song, Gangbing

    2013-01-01

    Shape memory alloy (SMA) actuators exhibit severe hysteresis, a nonlinear behavior, which complicates control strategies and limits their applications. This paper presents a new approach to controlling an SMA actuator through an adaptive inverse model based controller that consists of a dynamic neural network (DNN) identifier, a copy dynamic neural network (CDNN) feedforward term and a proportional (P) feedback action. Unlike fixed hysteresis models used in most inverse controllers, the proposed one uses a DNN to identify online the relationship between the applied voltage to the actuator and the displacement (the inverse model). Even without a priori knowledge of the SMA hysteresis and without pre-training, the proposed controller can precisely control the SMA wire actuator in various tracking tasks by identifying online the inverse model of the SMA actuator. Experiments were conducted, and experimental results demonstrated real-time modeling capabilities of DNN and the performance of the adaptive inverse controller. (paper)

  12. Dimensionality and effects of information motivation on users’ online social network advertising acceptance

    Directory of Open Access Journals (Sweden)

    IMRAN ANWAR MIR

    2018-04-01

    Full Text Available Social media has produced substantial changes in the communication landscape. Online social network sites (SNS grew as a common platform for online social interaction. SNS firms generate revenue from the advertising appearing on SNS. Their survival depends on users’ approval of such social network advertising (SNA. Marketing literature indicates that users accept advertising if it is consistent with their motivations for using social media. Information seeking is the most recognized SNS motivation. Yet, research on evaluating the influence of SNS information motivation on users’ approval of SNA is scarce. Based on SNS uses and gratifications theory, this study proposes a multidimensional model that shows the influence of SNS information motivation on users’ approval of SNA.

  13. Robustness analysis of the Zhang neural network for online time-varying quadratic optimization

    International Nuclear Information System (INIS)

    Zhang Yunong; Ruan Gongqin; Li Kene; Yang Yiwen

    2010-01-01

    A general type of recurrent neural network (termed as Zhang neural network, ZNN) has recently been proposed by Zhang et al for the online solution of time-varying quadratic-minimization (QM) and quadratic-programming (QP) problems. Global exponential convergence of the ZNN could be achieved theoretically in an ideal error-free situation. In this paper, with the normal differentiation and dynamics-implementation errors considered, the robustness properties of the ZNN model are investigated for solving these time-varying problems. In addition, linear activation functions and power-sigmoid activation functions could be applied to such a perturbed ZNN model. Both theoretical-analysis and computer-simulation results demonstrate the good ZNN robustness and superior performance for online time-varying QM and QP problem solving, especially when using power-sigmoid activation functions.

  14. Radiology online: information, education, and networking--a summary of the 2012 Intersociety Committee Summer Conference.

    Science.gov (United States)

    Dodd, Gerald D; Naeger, David M

    2013-05-01

    The "new online" (Web 2.0) world is evolving rapidly, and the digital information, education, and networking resources available to radiologists have exploded over the past 2 decades. The 2012 Intersociety Committee Summer Conference attendees explored the online resources that have been produced by societies, universities, and commercial entities. Specific attention was given to identifying the best products and packaging them in tablet computers for use by residents and practicing radiologists. The key functions of social networking websites and the possible roles they can play in radiology were explored as well. It was the consensus of the attendees that radiologic digital resources and portable electronic devices have matured to the point that they should become an integral part of our educational programs and clinical practice. Copyright © 2013 American College of Radiology. Published by Elsevier Inc. All rights reserved.

  15. Interprofessional Student Perspectives of Online Social Networks in Health and Business Education.

    Science.gov (United States)

    Doyle, Glynda; Jones, Cyri; Currie, Leanne

    2016-01-01

    The education sector is experiencing unprecedented change with the increasing use by students of mobile devices, social networks and e-portfolios as they prepare for future positions in the workforce. The purpose of this study was to examine student's preferences around these technologies. A mixed methods research strategy was used with an initial online survey using 29 Likert scale style questions to students from the School of Health Sciences and the School of Business at the British Columbia Institute of Technology (BCIT). Descriptive statistics and ANOVAs were performed to examine if there were any differences between groups regarding their overall responses to the survey questions. Content analysis was used for qualitative focus group data. Overall, students (n = 260) were enthusiastic about technology but wary of cost, lack of choice, increased workload and faculty involvement in their online social networks. Of note, students see significant value in face-to-face classroom time.

  16. Liking and hyperlinking: Community detection in online child sexual exploitation networks.

    Science.gov (United States)

    Westlake, Bryce G; Bouchard, Martin

    2016-09-01

    The online sexual exploitation of children is facilitated by websites that form virtual communities, via hyperlinks, to distribute images, videos, and other material. However, how these communities form, are structured, and evolve over time is unknown. Collected using a custom-designed webcrawler, we begin from known child sexual exploitation (CE) seed websites and follow hyperlinks to connected, related, websites. Using a repeated measure design we analyze 10 networks of 300 + websites each - over 4.8 million unique webpages in total, over a period of 60 weeks. Community detection techniques reveal that CE-related networks were dominated by two large communities hosting varied material -not necessarily matching the seed website. Community stability, over 60 weeks, varied across networks. Reciprocity in hyperlinking between community members was substantially higher than within the full network, however, websites were not more likely to connect to homogeneous-content websites. Copyright © 2016 Elsevier Inc. All rights reserved.

  17. Comparing social factors affecting recommender decisions in online and educational social network

    Science.gov (United States)

    MartÍn, Estefanía; Hernán-Losada, Isidoro; Haya, Pablo A.

    2016-01-01

    In the educational context, there is an increasing interest in learning networks. Recommender systems (RSs) can play an important role in achieving educational objectives. Although we can find many papers focused on recommendation techniques and algorithms, in general, less attention has been dedicated to social factors that influence the recommendation process. This process could be improved if we had a deeper understanding of the social factors that influence the quality or validity of a suggestion made by the RS. This work elucidates and analyses the social factors that influence the design and decision-making process of RSs. We conducted a survey in which 126 undergraduate students were asked to extract which are the main factors for improving suggestions when they are interacting with an Online Social Network (OSN) or in an Educational Social Network (ESN). The results show that different factors have to be considered depending on the type of network.

  18. CONSUMER OPINIONS TOWARDS ONLINE MARKETING COMMUNICATION AND ADVERTISING ON SOCIAL NETWORKS

    Directory of Open Access Journals (Sweden)

    GHEORGHE ORZAN

    2012-05-01

    Full Text Available On the Internet, a medium that has already proven its effectiveness in marketing activities, changes take place with astonishing speed. The recent explosion of social networking applications and their number of users has captured the marketers’ attention. Companies have started to rethink their relationships with consumers and adapt to the new online world. In this virtual world of social networks the public is the key element. Consumers perceive the social network as a personal space where they control the content. They decide on their own what they want to see and share with others. Thus, in order to manage marketing communications effectively, marketers must know the consumers’ opinions towards their presence in social networks.

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

    Directory of Open Access Journals (Sweden)

    Olumayowa Mulero

    2013-07-01

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

  20. A Game Theoretic Approach for Modeling Privacy Settings of an Online Social Network

    Directory of Open Access Journals (Sweden)

    Jundong Chen

    2014-05-01

    Full Text Available Users of online social networks often adjust their privacy settings to control how much information on their profiles is accessible to other users of the networks. While a variety of factors have been shown to affect the privacy strategies of these users, very little work has been done in analyzing how these factors influence each other and collectively contribute towards the users’ privacy strategies. In this paper, we analyze the influence of attribute importance, benefit, risk and network topology on the users’ attribute disclosure behavior by introducing a weighted evolutionary game model. Results show that: irrespective of risk, users aremore likely to reveal theirmost important attributes than their least important attributes; when the users’ range of influence is increased, the risk factor plays a smaller role in attribute disclosure; the network topology exhibits a considerable effect on the privacy in an environment with risk.

  1. Telecommunications Network Measurements of Online Gambling Behavior in Switzerland: A Feasibility Study.

    Science.gov (United States)

    Bitar, Raoul; Nordt, Carlos; Grosshans, Martin; Herdener, Marcus; Seifritz, Erich; Mutschler, Jochen

    2017-01-01

    Methodological shortcomings of gambling studies relying on self-report or on data sets derived from gambling operators tend to result in biased conclusions. The aim of this study was to analyze online gambling behavior using a novel network database approach. From October 13 to October 26, 2014, telecommunications network data from a major telecommunications provider in Switzerland were analyzed. Netflows between mobile devices and a poker operator were quantified to measure the gambling duration and session number. Time spent gambling during night and working hours was compared between devices with longest (red group), intermediate (orange group), and shortest gambling time (green group). Online gambling behavior differed depending on overall gambling time, F (2, 3,143). Night and working hours gambling was the highest in the red group (53%), compared to the orange (50.1%) and the green groups (41.5%). Post hoc analyses indicated significant differences between the orange and green groups (p < 0.05). No differences were observed between the red and orange groups (p = 0.850), and the red and green groups (p = 0.053). On mobile devices, distinct gambling patterns were observed depending on the overall gambling time. This methodology could also be used to investigate online gaming, social media use, and online pornography. © 2017 S. Karger AG, Basel.

  2. Interaction, Critical Thinking, and Social Network Analysis (SNA in Online Courses

    Directory of Open Access Journals (Sweden)

    Joan Thormann

    2013-07-01

    Full Text Available This study tried to ascertain a possible relationship between the number of student moderators (1, 2, and 3, online interactions, and critical thinking of K-12 educators enrolled in an online course that was taught from a constructivist approach. The course topic was use of technology in special education. Social network analysis (SNA and measures of critical thinking (Newman, Webb, & Cochrane, 1995 were used to research and assess if there was a difference in interaction and critical thinking between 1, 2, or 3 student moderators who facilitated a forum discussion of an assignment in an online course. The same course was repeated over three years. Each year either 1, 2, or 3 students moderated. The analysis indicated more discussion per non-moderating student with the three student moderated group. Using SNA we found that there was only one noticeable difference among the three groups which was in the value of network centralization. Using critical thinking measures the three student moderator group scored higher in five of the eight critical thinking categories. Variations in instructor presence in the online courses may have influenced these findings.

  3. Talking about your health to strangers: understanding the use of online social networks by patients

    Science.gov (United States)

    Colineau, Nathalie; Paris, Cécile

    2010-04-01

    The internet has become a participatory place where everyone can contribute and interact with others. In health in particular, social media have changed traditional patient-physician relationships. Patients are organising themselves in groups, sharing observations and helping each other, although there is still little evidence of the effectiveness of these online communities on people's health. To understand why and how people use health-related sites, we studied these sites and identified three dimensions characterising most of them: informational/supportive; general/focused; and new relationships/existing ones. We conducted an online survey about the use of health-related social networking (SN) sites and learnt that, consistent with previous research, most patients were seeking information about their medical condition online, while, at the same time, still interacting with health professionals to talk about sensitive information and complex issues. We also found that, while people's natural social network played an important role for emotional support, sometimes, people chose to not involve their family, but instead interact with peers online because of their perceived support and ability to understand someone's experience, and also to maintain a comfortable emotional distance. Finally, our results show that people using general SN sites do not necessarily use health-related sites and vice versa.

  4. Transputer networks for the on-line analysis of fine-grained electromagnetic calorimeter data

    International Nuclear Information System (INIS)

    Girotto, G.L.; Lanceri, L.; Scuri, F.; Zoppolato, E.

    1994-01-01

    Transputer networks, designed to perform parallel computations, are well suited for data acquisition, on-line analysis and second level trigger tasks in high energy physics experiments. Some simple algorithms for the analysis of fine-grained electromagnetic calorimeter data were implemented on two types of transputer networks and tested on real and simulated data from a silicon-tungsten calorimeter. Results are presented on the processing speed, measured in a test setup, and extrapolations to a full size detector and data acquisition system are discussed. ((orig.))

  5. Design to Thrive Creating Social Networks and Online Communities that Last

    CERN Document Server

    Howard, Tharon W

    2010-01-01

    Social networks and online communities are reshaping the way people communicate, both in their personal and professional lives. What makes some succeed and others fail? What draws a user in? What makes them join? What keeps them coming back? Entrepreneurs and businesses are turning to user experience practitioners to figure this out. Though they are well-equipped to evaluate and create a variety of interfaces, social networks require a different set of design principles and ways of thinking about the user in order to be successful. .. .. Design to Thrive presents tried and tested design method

  6. Wavelet Network: Online Sequential Extreme Learning Machine for Nonlinear Dynamic Systems Identification

    Directory of Open Access Journals (Sweden)

    Dhiadeen Mohammed Salih

    2015-01-01

    Full Text Available A single hidden layer feedforward neural network (SLFN with online sequential extreme learning machine (OSELM algorithm has been introduced and applied in many regression problems successfully. However, using SLFN with OSELM as black-box for nonlinear system identification may lead to building models for the identified plant with inconsistency responses from control perspective. The reason can refer to the random initialization procedure of the SLFN hidden node parameters with OSELM algorithm. In this paper, a single hidden layer feedforward wavelet network (WN is introduced with OSELM for nonlinear system identification aimed at getting better generalization performances by reducing the effect of a random initialization procedure.

  7. Wavelet Network: Online Sequential Extreme Learning Machine for Nonlinear Dynamic Systems Identification

    OpenAIRE

    Dhiadeen Mohammed Salih; Samsul Bahari Mohd Noor; Mohammad Hamiruce Merhaban; Raja Mohd Kamil

    2015-01-01

    A single hidden layer feedforward neural network (SLFN) with online sequential extreme learning machine (OSELM) algorithm has been introduced and applied in many regression problems successfully. However, using SLFN with OSELM as black-box for nonlinear system identification may lead to building models for the identified plant with inconsistency responses from control perspective. The reason can refer to the random initialization procedure of the SLFN hidden node parameters with OSELM algorit...

  8. Pharmacy faculty members' perspectives on the student/faculty relationship in online social networks.

    Science.gov (United States)

    Metzger, Anne H; Finley, Kristen N; Ulbrich, Timothy R; McAuley, James W

    2010-12-15

    To describe pharmacy faculty members' use of the online social network Facebook and compare the perspectives of faculty members with and without Facebook profiles regarding student/faculty relationships. An electronic survey instrument was sent to full-time faculty members (n = 183) at 4 colleges of pharmacy in Ohio seeking their opinions on student/faculty relationships on Facebook. If respondents answered "yes" to having a Facebook profile, they were asked 14 questions on aspects of being "friends" with students. If respondents answered "no," they were asked 4 questions. Of the 95 respondents (52%) to the survey instrument, 44 faculty members (46%) had a Facebook profile, while 51 faculty members (54%) did not. Those who had a profile had been faculty members for an average of 8.6 years, versus 11.4 years for those who did not have a Facebook profile. Seventy-nine percent of faculty members who used Facebook were not "friends" with their students. The majority of respondents reported that they would decline/ignore a "friend" request from a student, or decline until after the student graduated. Although a limited number of faculty members had used Facebook for online discussions, teaching purposes, or student organizations, the majority of universities did not have policies on the use of social networking sites. Online social network sites are used widely by students and faculty members, which may raise questions regarding professionalism and appropriate faculty/student relationships. Further research should address the student/preceptor relationship, other online social networking sites, and whether students are interested in using these sites within the classroom and/or professional organizations.

  9. Does Posting Facebook Status Updates Increase or Decrease Loneliness? An Online Social Networking Experiment

    OpenAIRE

    Deters, Fenne große; Mehl, Matthias R.

    2012-01-01

    Online social networking is a pervasive but empirically understudied phenomenon. Strong public opinions on its consequences exist but are backed up by little empirical evidence and almost no causally-conclusive, experimental research. The current study tested the psychological effects of posting status updates on Facebook using an experimental design. For one week, participants in the experimental condition were asked to post more than they usually do, whereas participants in the control cond...

  10. Interaction patterns of nurturant support exchanged in online health social networking.

    Science.gov (United States)

    Chuang, Katherine Y; Yang, Christopher C

    2012-05-03

    Expressing emotion in online support communities is an important aspect of enabling e-patients to connect with each other and expand their social resources. Indirectly it increases the amount of support for coping with health issues. Exploring the supportive interaction patterns in online health social networking would help us better understand how technology features impacts user behavior in this context. To build on previous research that identified different types of social support in online support communities by delving into patterns of supportive behavior across multiple computer-mediated communication formats. Each format combines different architectural elements, affecting the resulting social spaces. Our research question compared communication across different formats of text-based computer-mediated communication provided on the MedHelp.org health social networking environment. We identified messages with nurturant support (emotional, esteem, and network) across three different computer-mediated communication formats (forums, journals, and notes) of an online support community for alcoholism using content analysis. Our sample consisted of 493 forum messages, 423 journal messages, and 1180 notes. Nurturant support types occurred frequently among messages offering support (forum comments: 276/412 messages, 67.0%; journal posts: 65/88 messages, 74%; journal comments: 275/335 messages, 82.1%; and notes: 1002/1180 messages, 84.92%), but less often among messages requesting support. Of all the nurturing supports, emotional (ie, encouragement) appeared most frequently, with network and esteem support appearing in patterns of varying combinations. Members of the Alcoholism Community appeared to adapt some traditional face-to-face forms of support to their needs in becoming sober, such as provision of encouragement, understanding, and empathy to one another. The computer-mediated communication format may have the greatest influence on the supportive interactions

  11. Actual versus perceived peer sexual risk behavior in online youth social networks

    OpenAIRE

    Black, Sandra R; Schmiege, Sarah; Bull, Sheana

    2013-01-01

    Perception of peer behaviors is an important predictor of actual risk behaviors among youth. However, we lack understanding of peer influence through social media and of actual and perceived peer behavior concordance. The purpose of this research is to document the relationship between individual perception of and actual peer sexual risk behavior using online social networks. The data are a result of a secondary analysis of baseline self-reported and peer-reported sexual risk behavior from a ...

  12. Social Networks Used by Teens and Parental Control of Their Online Communication

    OpenAIRE

    M. Shehu; Y. Zhurda

    2017-01-01

    The Internet plays important functions in identity formation, personal autono-my, and relationships outside the family. It allows teens to develop their own interests, to identify with others. The aim of the study is to present concrete evidence regarding to the communication through social networks and parental care in the management of online communication. Referring questionnaire “Student Needs Assessment Survey” by N. E. Willard (2007), but the author has selected questions to the scope o...

  13. Online Sequence Training of Recurrent Neural Networks with Connectionist Temporal Classification

    OpenAIRE

    Hwang, Kyuyeon; Sung, Wonyong

    2015-01-01

    Connectionist temporal classification (CTC) based supervised sequence training of recurrent neural networks (RNNs) has shown great success in many machine learning areas including end-to-end speech and handwritten character recognition. For the CTC training, however, it is required to unroll (or unfold) the RNN by the length of an input sequence. This unrolling requires a lot of memory and hinders a small footprint implementation of online learning or adaptation. Furthermore, the length of tr...

  14. Online identity: constructing interpersonal trust and openness through participating in hospitality social networks

    OpenAIRE

    Alexander Ronzhyn

    2013-01-01

    The present article describes the results of research on online identity construction during the participation in the hospitality social networks. Specifically the user references are analysed to understand patterns that form the image of a member. CouchSurfing service (couchsurfing.org) allows users to leave short texts where the experience of hosting/being hosted by a CS member is described, is an evaluation of the CS members of each other’s personal traits, skills and common experience....

  15. Online and social networking interventions for the treatment of depression in young people: a systematic review.

    Science.gov (United States)

    Rice, Simon M; Goodall, Joanne; Hetrick, Sarah E; Parker, Alexandra G; Gilbertson, Tamsyn; Amminger, G Paul; Davey, Christopher G; McGorry, Patrick D; Gleeson, John; Alvarez-Jimenez, Mario

    2014-09-16

    Major depression accounts for the greatest burden of all diseases globally. The peak onset of depression occurs between adolescence and young adulthood, and for many individuals, depression displays a relapse-remitting and increasingly severe course. Given this, the development of cost-effective, acceptable, and population-focused interventions for depression is critical. A number of online interventions (both prevention and acute phase) have been tested in young people with promising results. As these interventions differ in content, clinician input, and modality, it is important to identify key features (or unhelpful functions) associated with treatment outcomes. A systematic review of the research literature was undertaken. The review was designed to focus on two aspects of online intervention: (1) standard approaches evaluating online intervention content in randomized controlled designs (Section 1), and (2) second-generation online interventions and services using social networking (eg, social networking sites and online support groups) in any type of research design (Section 2). Two specific literature searches were undertaken. There was no date range specified. The Section 1 search, which focused on randomized controlled trials, included only young people (12-25 years) and yielded 101 study abstracts, of which 15 met the review inclusion criteria. The Section 2 search, which included all study design types and was not restricted in terms of age, yielded 358 abstracts, of which 22 studies met the inclusion criteria. Information about the studies and their findings were extracted and tabulated for review. The 15 studies identified in Section 1 described 10 trials testing eight different online interventions, all of which were based on a cognitive behavioral framework. All but one of the eight identified studies reported positive results; however, only five of the 15 studies used blinded interviewer administered outcomes with most trials using self-report data

  16. Words Analysis of Online Chinese News Headlines about Trending Events: A Complex Network Perspective

    Science.gov (United States)

    Li, Huajiao; Fang, Wei; An, Haizhong; Huang, Xuan

    2015-01-01

    Because the volume of information available online is growing at breakneck speed, keeping up with meaning and information communicated by the media and netizens is a new challenge both for scholars and for companies who must address public relations crises. Most current theories and tools are directed at identifying one website or one piece of online news and do not attempt to develop a rapid understanding of all websites and all news covering one topic. This paper represents an effort to integrate statistics, word segmentation, complex networks and visualization to analyze headlines’ keywords and words relationships in online Chinese news using two samples: the 2011 Bohai Bay oil spill and the 2010 Gulf of Mexico oil spill. We gathered all the news headlines concerning the two trending events in the search results from Baidu, the most popular Chinese search engine. We used Simple Chinese Word Segmentation to segment all the headlines into words and then took words as nodes and considered adjacent relations as edges to construct word networks both using the whole sample and at the monthly level. Finally, we develop an integrated mechanism to analyze the features of words’ networks based on news headlines that can account for all the keywords in the news about a particular event and therefore track the evolution of news deeply and rapidly. PMID:25807376

  17. Words analysis of online Chinese news headlines about trending events: a complex network perspective.

    Directory of Open Access Journals (Sweden)

    Huajiao Li

    Full Text Available Because the volume of information available online is growing at breakneck speed, keeping up with meaning and information communicated by the media and netizens is a new challenge both for scholars and for companies who must address public relations crises. Most current theories and tools are directed at identifying one website or one piece of online news and do not attempt to develop a rapid understanding of all websites and all news covering one topic. This paper represents an effort to integrate statistics, word segmentation, complex networks and visualization to analyze headlines' keywords and words relationships in online Chinese news using two samples: the 2011 Bohai Bay oil spill and the 2010 Gulf of Mexico oil spill. We gathered all the news headlines concerning the two trending events in the search results from Baidu, the most popular Chinese search engine. We used Simple Chinese Word Segmentation to segment all the headlines into words and then took words as nodes and considered adjacent relations as edges to construct word networks both using the whole sample and at the monthly level. Finally, we develop an integrated mechanism to analyze the features of words' networks based on news headlines that can account for all the keywords in the news about a particular event and therefore track the evolution of news deeply and rapidly.

  18. Local Spatial Obesity Analysis and Estimation Using Online Social Network Sensors.

    Science.gov (United States)

    Sun, Qindong; Wang, Nan; Li, Shancang; Zhou, Hongyi

    2018-03-15

    Recently, the online social networks (OSNs) have received considerable attentions as a revolutionary platform to offer users massive social interaction among users that enables users to be more involved in their own healthcare. The OSNs have also promoted increasing interests in the generation of analytical, data models in health informatics. This paper aims at developing an obesity identification, analysis, and estimation model, in which each individual user is regarded as an online social network 'sensor' that can provide valuable health information. The OSN-based obesity analytic model requires each sensor node in an OSN to provide associated features, including dietary habit, physical activity, integral/incidental emotions, and self-consciousness. Based on the detailed measurements on the correlation of obesity and proposed features, the OSN obesity analytic model is able to estimate the obesity rate in certain urban areas and the experimental results demonstrate a high success estimation rate. The measurements and estimation experimental findings created by the proposed obesity analytic model show that the online social networks could be used in analyzing the local spatial obesity problems effectively. Copyright © 2018. Published by Elsevier Inc.

  19. Social comparison 2.0: examining the effects of online profiles on social-networking sites.

    Science.gov (United States)

    Haferkamp, Nina; Krämer, Nicole C

    2011-05-01

    Through their features--such as profile photographs or the personal vita--online profiles on social-networking sites offer a perfect basis for social comparison processes. By looking at the profile photograph, the user gains an impression of a person's physical attractiveness, and the user's vita shows which career path the person is pursuing. Against the background of Festinger's Social Comparison Theory, the focus of this research is on the effects of online profiles on their recipients. Therefore, qualitative interviews (N = 12) and two online experiments were conducted in which virtual online profiles of either physically attractive or unattractive persons (N = 93) and profiles of users with either high or low occupational attainment (N = 103) were presented to the participants. Although qualitative interviews did not initially give reason to expect online profiles to constitute a basis for comparison processes, results of the experiments proved otherwise. The first study indicates that recipients have a more negative body image after looking at beautiful users than persons who were shown the less attractive profile pictures. Male participants of the second study, who were confronted with profiles of successful males, showed a higher perceived discrepancy between their current career status and an ideal vita than male participants who looked at profiles of less successful persons.

  20. Finding The Most Important Actor in Online Crowd by Social Network Analysis

    Science.gov (United States)

    Yuliana, I.; Santosa, P. I.; Setiawan, N. A.; Sukirman

    2017-02-01

    Billion of people create trillions of connections through social media every single day. The increasing use of social media has led to dramatic changes in the of way science, government, healthcare, entertainment and enterprise operate. Large-scale participation in Technology-Mediated Social Participation (TMSP) system has opened up incredible new opportunities to deploy online crowd. This descriptive-correlational research used social network analysis (SNA) on data gathered from Fanpage Facebook of Greenpeace Indonesia related to important critical issues, the bushfires in 2015. SNA identifies relations on each member by sociometrics parameter such as three centrality (degree, closeness and betweenesse) for measuring and finding the most important actor in the online community. This paper use Fruchterman Rein-gold algorithm to visualize the online community in a graph, while Clauset-Newman-Moore is a technique to identify groups in community. As the result found 3735 vertices related to actors, 6927 edges as relation, 14 main actors in size order and 22 groups in Greenpeace Indonesia online community. This research contributes to organize some information for Greenpeace Indonesia managing their potency in online community to identify human behaviour.

  1. To View or Not To View: The Influence of Social Networks and Subjective Norms on Online Pornography Consumption

    Directory of Open Access Journals (Sweden)

    Wan-Ying Lin

    2012-06-01

    Full Text Available This study investigates the influence of social networks and subjective norms on an individual’s online pornography consumption. The empirical survey results of 324 voluntary participants indicated that the individual’s positive outcome evaluation was associated with a higher level of online pornography exposure. Social pressure also plays a significant, but negative, role in one’s viewing decision.

  2. Your Health Buddies Matter: Preferential Selection and Social Influence on Weight Management in an Online Health Social Network.

    Science.gov (United States)

    Meng, Jingbo

    2016-12-01

    A growing number of online social networks are designed with the intention to promote health by providing virtual space wherein individuals can seek and share information and support with similar others. Research has shown that real-world social networks have a significant influence on one's health behavior and outcomes. However, there is a dearth of studies on how individuals form social networks in virtual space and whether such online social networks exert any impact on individuals' health outcomes. Built on the Multi-Theoretical Multilevel (MTML) framework and drawing from literature on social influence, this study examined the mechanisms underlying the formation of an online health social network and empirically tested social influence on individual health outcomes through the network. Situated in a weight management social networking site, the study tracked a health buddy network of 709 users and their weight management activities and outcomes for 4 months. Actor-based modeling was used to test the joint dynamics of preferential selection and social influence among health buddies. The results showed that baseline, inbreeding, and health status homophily significantly predicted preferential selection of health buddies in the weight management social networking site, whereas self-interest in seeking experiential health information did not. The study also found peer influence of online health buddy networks on individual weight outcomes, such that an individual's odds of losing weight increased if, on average, the individual's health buddies were losing weight.

  3. Social dilemmas in an online social network: The structure and evolution of cooperation

    International Nuclear Information System (INIS)

    Fu Feng; Chen Xiaojie; Liu Lianghuan; Wang Long

    2007-01-01

    We investigate two paradigms for studying the evolution of cooperation-Prisoner's Dilemma and Snowdrift game in an online friendship network, obtained from a social networking site. By structural analysis, it is revealed that the empirical social network has small-world and scale-free properties. Besides, it exhibits assortative mixing pattern. Then, we study the evolutionary version of the two types of games on it. It is found that cooperation is substantially promoted with small values of game matrix parameters in both games. Whereas the competent cooperators induced by the underlying network of contacts will be dramatically inhibited with increasing values of the game parameters. Further, we explore the role of assortativity in evolution of cooperation by random edge rewiring. We find that increasing amount of assortativity will to a certain extent diminish the cooperation level. We also show that connected large hubs are capable of maintaining cooperation. The evolution of cooperation on empirical networks is influenced by various network effects in a combined manner, compared with that on model networks. Our results can help understand the cooperative behaviors in human groups and society

  4. Online Expansion Technology for Dynamic Topology Changing ZigBee Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Md. Emdadul Haque

    2014-03-01

    Full Text Available In ZigBee, the router capable devices have restriction to accept a number of devices as children devices. A router capable device can not allow any new device to join as a child device if it reaches to the maximum capacity of children or depth limit. According to ZigBee specification each device has a permanent 64-bit MAC address. If a device joins a ZigBee network, it receives a short 16-bit MAC address from the parent device. If a device can not join a network, it isolates from the network and becomes an orphan node even though address spaces are available in the network. The orphan problem becomes worse when the topology of the network changes dynamically. In this paper we propose an online expansion technology to connect the maximum number of devices specially for dynamic topology changing ZigBee wireless sensor networks. The proposed technology shares available address spaces of the router devices to reduce the number of orphan nodes in the network.

  5. The research of development dynamics of electronic social networks for the effective advertisement of online shops in the segment of Ukrainian network business

    Directory of Open Access Journals (Sweden)

    O.I. Grabar

    2015-09-01

    Full Text Available The article presents the research results of development dynamics of the Ukrainian segment of different social networks in the global network. The general methods of creation and development of online shop are described. The methods of creation and development of marketing communications for online shops and their influence on the development of electronic business in Ukraine are presented. The article gives the detailed analysis of statistical data on age & gender related distribution of the Ukrainian segment of the biggest world social networks. The author also introduces new instruments for marketing communications worked out by every social network. The basic principles of advertisement campaign realization for online shops with the use of target audience of certain groups in social networks are generalized.

  6. Ambient awareness: From random noise to digital closeness in online social networks.

    Science.gov (United States)

    Levordashka, Ana; Utz, Sonja

    2016-07-01

    Ambient awareness refers to the awareness social media users develop of their online network in result of being constantly exposed to social information, such as microblogging updates. Although each individual bit of information can seem like random noise, their incessant reception can amass to a coherent representation of social others. Despite its growing popularity and important implications for social media research, ambient awareness on public social media has not been studied empirically. We provide evidence for the occurrence of ambient awareness and examine key questions related to its content and functions. A diverse sample of participants reported experiencing awareness, both as a general feeling towards their network as a whole, and as knowledge of individual members of the network, whom they had not met in real life. Our results indicate that ambient awareness can develop peripherally, from fragmented information and in the relative absence of extensive one-to-one communication. We report the effects of demographics, media use, and network variables and discuss the implications of ambient awareness for relational and informational processes online.

  7. Understanding Online Health Groups for Depression: Social Network and Linguistic Perspectives.

    Science.gov (United States)

    Xu, Ronghua; Zhang, Qingpeng

    2016-03-10

    Mental health problems have become increasingly prevalent in the past decade. With the advance of Web 2.0 technologies, social media present a novel platform for Web users to form online health groups. Members of online health groups discuss health-related issues and mutually help one another by anonymously revealing their mental conditions, sharing personal experiences, exchanging health information, and providing suggestions and support. The conversations in online health groups contain valuable information to facilitate the understanding of their mutual help behaviors and their mental health problems. We aimed to characterize the conversations in a major online health group for major depressive disorder (MDD) patients in a popular Chinese social media platform. In particular, we intended to explain how Web users discuss depression-related issues from the perspective of the social networks and linguistic patterns revealed by the members' conversations. Social network analysis and linguistic analysis were employed to characterize the social structure and linguistic patterns, respectively. Furthermore, we integrated both perspectives to exploit the hidden relations between them. We found an intensive use of self-focus words and negative affect words. In general, group members used a higher proportion of negative affect words than positive affect words. The social network of the MDD group for depression possessed small-world and scale-free properties, with a much higher reciprocity ratio and clustering coefficient value as compared to the networks of other social media platforms and classic network models. We observed a number of interesting relationships, either strong correlations or convergent trends, between the topological properties and linguistic properties of the MDD group members. (1) The MDD group members have the characteristics of self-preoccupation and negative thought content, according to Beck's cognitive theory of depression; (2) the social structure

  8. Adaptive online state-of-charge determination based on neuro-controller and neural network

    Energy Technology Data Exchange (ETDEWEB)

    Shen Yanqing, E-mail: network_hawk@126.co [Department of Automation, Chongqing Industry Polytechnic College, Jiulongpo District, Chongqing 400050 (China)

    2010-05-15

    This paper presents a novel approach using adaptive artificial neural network based model and neuro-controller for online cell State of Charge (SOC) determination. Taking cell SOC as model's predictive control input unit, radial basis function neural network, which can adjust its structure to prediction error with recursive least square algorithm, is used to simulate battery system. Besides that, neuro-controller based on Back-Propagation Neural Network (BPNN) and modified PID controller is used to decide the control input of battery system, i.e., cell SOC. Finally this algorithm is applied for the SOC determination of lead-acid batteries, and results of lab tests on physical cells, compared with model prediction, are presented. Results show that the ANN based battery system model adaptively simulates battery system with great accuracy, and the predicted SOC simultaneously converges to the real value quickly within the error of +-1 as time goes on.

  9. Stability analysis and control models for rumor spreading in online social networks

    Science.gov (United States)

    Jiang, Ping; Yan, Xiangbin

    This paper establishes a novel Susceptible-Infected-Removed (SIR) rumor spreading model for online social networks (OSNs). The model utilizes the node degree to describe the dynamic changes of the number of rumor spreaders and it can be regarded as an extension of the traditional SIR model. Stability analysis of the model reveals that the spreader in social networks has a basic reproduction number. If the basic reproduction number is less than 1, then rumors will disappear. Otherwise, rumors will persist. According to this result, we can predict the trend of rumor spreading. Then we propose an immune-structure SIR model to explore the control method of rumor spreading. Stability analysis and numerical simulation of the model indicate that immunizing susceptible individual is an effective method to control rumors. Further, the immune-structure model explains that the network structure decides the choice of immune methods. Our findings offer some new insights to control the spread of rumors on OSNs.

  10. Mental disorder recovery correlated with centralities and interactions on an online social network

    Directory of Open Access Journals (Sweden)

    Xinpei Ma

    2015-08-01

    Full Text Available Recent research has established both a theoretical basis and strong empirical evidence that effective social behavior plays a beneficial role in the maintenance of physical and psychological well-being of people. To test whether social behavior and well-being are also associated in online communities, we studied the correlations between the recovery of patients with mental disorders and their behaviors in online social media. As the source of the data related to the social behavior and progress of mental recovery, we used PatientsLikeMe (PLM, the world’s first open-participation research platform for the development of patient-centered health outcome measures. We first constructed an online social network structure based on patient-to-patient ties among 200 patients obtained from PLM. We then characterized patients’ online social activities by measuring the numbers of “posts and views” and “helpful marks” each patient obtained. The patients’ recovery data were obtained from their self-reported status information that was also available on PLM. We found that some node properties (in-degree, eigenvector centrality and PageRank and the two online social activity measures were significantly correlated with patients’ recovery. Furthermore, we re-collected the patients’ recovery data two months after the first data collection. We found significant correlations between the patients’ social behaviors and the second recovery data, which were collected two months apart. Our results indicated that social interactions in online communities such as PLM were significantly associated with the current and future recoveries of patients with mental disorders.

  11. The Emergence of Contesting Motives for Student Feedback-Based Evaluation in Australian Higher Education

    Science.gov (United States)

    Darwin, Stephen

    2016-01-01

    Student feedback-based evaluation performs a significant social role in framing perceptions of the quality of teaching in contemporary Australian higher education. Yet its emergence is a relatively recent phenomenon, having only been in widespread application since the mid-1980s. The early manifestations of student feedback-based evaluation came…

  12. Using posts to an online social network to assess fishing effort

    Science.gov (United States)

    Martin, Dustin R.; Chizinski, Christopher J.; Eskridge, Kent M.; Pope, Kevin L

    2014-01-01

    Fisheries management has evolved from reservoir to watershed management, creating a need to simultaneously gather information within and across interacting reservoirs. However, costs to gather information on the fishing effort on multiple reservoirs using traditional creel methodology are often prohibitive. Angler posts about reservoirs online provide a unique medium to test hypotheses on the distribution of fishing pressure. We show that the activity on an online fishing social network is related to fishing effort and can be used to facilitate management goals. We searched the Nebraska Fish and Game Association Fishing Forum for all references from April 2009 to December 2010 to 19 reservoirs that comprise the Salt Valley regional fishery in southeastern Nebraska. The number of posts was positively related to monthly fishing effort on a regional scale, with individual reservoirs having the most annual posts also having the most annual fishing effort. Furthermore, this relationship held temporally. Online fishing social networks provide the potential to assess effort on larger spatial scales than currently feasible.

  13. Look at me! Look at me! Self-representation and self-exposure through online networks

    Directory of Open Access Journals (Sweden)

    Kerry Mallan

    2009-05-01

    Full Text Available With the ever more user-friendly Web, the opportunities to use available channels of online communication complicate ways in which individuals oscillate between exhibition and inhibition, self-exposure and self-preservation, authenticity and deception. This paper draws on empirical research with high school students to examine the ways in which youth represent themselves and interact with friends and others in online networks such as MySpace. The conceptual framework for the discussion draws on the politics of visibility and notions of spatiality. These twin factors have consequences for new modes of technologically-mediated modes of representation with respect to community, friends, communication, and recognition. They also are helpful for considering what self-exposure means in terms of trust, risk, and privacy. The paper argues that there is no escaping the fact that online networks and other related activities hold both promise and peril. However, in constructing new social practices that traverse public and private spaces, technology itself is a key player in shaping how a community contributes to an individual’s identity formation and social activities.

  14. Association between online social networking and depression in high school students: behavioral physiology viewpoint.

    Science.gov (United States)

    Pantic, Igor; Damjanovic, Aleksandar; Todorovic, Jovana; Topalovic, Dubravka; Bojovic-Jovic, Dragana; Ristic, Sinisa; Pantic, Senka

    2012-03-01

    Frequent use of Facebook and other social networks is thought to be associated with certain behavioral changes, and some authors have expressed concerns about its possible detrimental effect on mental health. In this work, we investigated the relationship between social networking and depression indicators in adolescent population. Total of 160 high school students were interviewed using an anonymous, structured questionnaire and Back Depression Inventory - second edition (BDI-II-II). Apart from BDI-II-II, students were asked to provide the data for height and weight, gender, average daily time spent on social networking sites, average time spent watching TV, and sleep duration in a 24-hour period. Average BDI-II-II score was 8.19 (SD=5.86). Average daily time spent on social networking was 1.86 h (SD=2.08 h), and average time spent watching TV was 2.44 h (SD=1.74 h). Average body mass index of participants was 21.84 (SD=3.55) and average sleep duration was 7.37 (SD=1.82). BDI-II-II score indicated minimal depression in 104 students, mild depression in 46 students, and moderate depression in 10 students. Statistically significant positive correlation (psocial networking. Our results indicate that online social networking is related to depression. Additional research is required to determine the possible causal nature of this relationship.

  15. Enforcement of Privacy Policies over Multiple Online Social Networks for Collaborative Activities

    Science.gov (United States)

    Wu, Zhengping; Wang, Lifeng

    Our goal is to tend to develop an enforcement architecture of privacy policies over multiple online social networks. It is used to solve the problem of privacy protection when several social networks build permanent or temporary collaboration. Theoretically, this idea is practical, especially due to more and more social network tend to support open source framework “OpenSocial”. But as we known different social network websites may have the same privacy policy settings based on different enforcement mechanisms, this would cause problems. In this case, we have to manually write code for both sides to make the privacy policy settings enforceable. We can imagine that, this is a huge workload based on the huge number of current social networks. So we focus on proposing a middleware which is used to automatically generate privacy protection component for permanent integration or temporary interaction of social networks. This middleware provide functions, such as collecting of privacy policy of each participant in the new collaboration, generating a standard policy model for each participant and mapping all those standard policy to different enforcement mechanisms of those participants.

  16. Non-linguistic learning and aphasia: Evidence from a paired associate and feedback-based task

    Science.gov (United States)

    Vallila-Rohter, Sofia; Kiran, Swathi

    2013-01-01

    Though aphasia is primarily characterized by impairments in the comprehension and/or expression of language, research has shown that patients with aphasia also show deficits in cognitive-linguistic domains such as attention, executive function, concept knowledge and memory (Helm-Estabrooks, 2002 for review). Research in aphasia suggests that cognitive impairments can impact the online construction of language, new verbal learning, and transactional success (Freedman & Martin, 2001; Hula & McNeil, 2008; Ramsberger, 2005). In our research, we extend this hypothesis to suggest that general cognitive deficits influence progress with therapy. The aim of our study is to explore learning, a cognitive process that is integral to relearning language, yet underexplored in the field of aphasia rehabilitation. We examine non-linguistic category learning in patients with aphasia (n=19) and in healthy controls (n=12), comparing feedback and non-feedback based instruction. Participants complete two computer-based learning tasks that require them to categorize novel animals based on the percentage of features shared with one of two prototypes. As hypothesized, healthy controls showed successful category learning following both methods of instruction. In contrast, only 60% of our patient population demonstrated successful non-linguistic category learning. Patient performance was not predictable by standardized measures of cognitive ability. Results suggest that general learning is affected in aphasia and is a unique, important factor to consider in the field of aphasia rehabilitation. PMID:23127795

  17. Non-linguistic learning and aphasia: evidence from a paired associate and feedback-based task.

    Science.gov (United States)

    Vallila-Rohter, Sofia; Kiran, Swathi

    2013-01-01

    Though aphasia is primarily characterized by impairments in the comprehension and/or expression of language, research has shown that patients with aphasia also show deficits in cognitive-linguistic domains such as attention, executive function, concept knowledge and memory. Research in aphasia suggests that cognitive impairments can impact the online construction of language, new verbal learning, and transactional success. In our research, we extend this hypothesis to suggest that general cognitive deficits influence progress with therapy. The aim of our study is to explore learning, a cognitive process that is integral to relearning language, yet underexplored in the field of aphasia rehabilitation. We examine non-linguistic category learning in patients with aphasia (n=19) and in healthy controls (n=12), comparing feedback and non-feedback based instruction. Participants complete two computer-based learning tasks that require them to categorize novel animals based on the percentage of features shared with one of two prototypes. As hypothesized, healthy controls showed successful category learning following both methods of instruction. In contrast, only 60% of our patient population demonstrated successful non-linguistic category learning. Patient performance was not predictable by standardized measures of cognitive ability. Results suggest that general learning is affected in aphasia and is a unique, important factor to consider in the field of aphasia rehabilitation. Copyright © 2012 Elsevier Ltd. All rights reserved.

  18. Friending, IMing, and hanging out face-to-face: overlap in adolescents' online and offline social networks.

    Science.gov (United States)

    Reich, Stephanie M; Subrahmanyam, Kaveri; Espinoza, Guadalupe

    2012-03-01

    Many new and important developmental issues are encountered during adolescence, which is also a time when Internet use becomes increasingly popular. Studies have shown that adolescents are using these online spaces to address developmental issues, especially needs for intimacy and connection to others. Online communication with its potential for interacting with unknown others, may put teens at increased risk. Two hundred and fifty-one high school students completed an in-person survey, and 126 of these completed an additional online questionnaire about how and why they use the Internet, their activities on social networking sites (e.g., Facebook, MySpace) and their reasons for participation, and how they perceive these online spaces to impact their friendships. To examine the extent of overlap between online and offline friends, participants were asked to list the names of their top interaction partners offline and online (Facebook and instant messaging). Results reveal that adolescents mainly use social networking sites to connect with others, in particular with people known from offline contexts. While adolescents report little monitoring by their parents, there was no evidence that teens are putting themselves at risk by interacting with unknown others. Instead, adolescents seem to use the Internet, especially social networking sites, to connect with known others. While the study found moderate overlap between teens' closest online and offline friends, the patterns suggest that adolescents use online contexts to strengthen offline relationships. PsycINFO Database Record (c) 2012 APA, all rights reserved.

  19. Context-specific protein network miner - an online system for exploring context-specific protein interaction networks from the literature

    KAUST Repository

    Chowdhary, Rajesh

    2012-04-06

    Background: Protein interaction networks (PINs) specific within a particular context contain crucial information regarding many cellular biological processes. For example, PINs may include information on the type and directionality of interaction (e.g. phosphorylation), location of interaction (i.e. tissues, cells), and related diseases. Currently, very few tools are capable of deriving context-specific PINs for conducting exploratory analysis. Results: We developed a literature-based online system, Context-specific Protein Network Miner (CPNM), which derives context-specific PINs in real-time from the PubMed database based on a set of user-input keywords and enhanced PubMed query system. CPNM reports enriched information on protein interactions (with type and directionality), their network topology with summary statistics (e.g. most densely connected proteins in the network; most densely connected protein-pairs; and proteins connected by most inbound/outbound links) that can be explored via a user-friendly interface. Some of the novel features of the CPNM system include PIN generation, ontology-based PubMed query enhancement, real-time, user-queried, up-to-date PubMed document processing, and prediction of PIN directionality. Conclusions: CPNM provides a tool for biologists to explore PINs. It is freely accessible at http://www.biotextminer.com/CPNM/. © 2012 Chowdhary et al.

  20. Active Probing Feedback based Self Configurable Intelligent Distributed Antenna System

    DEFF Research Database (Denmark)

    Kumar, Ambuj

    collectively as Place Time Coverage & Capacity (PTC2). The dissertation proves through the concept of the PTC2 that the network performance can severely be degraded by the excessive and unrealistic site demands, the network management inefficiency, and the consequence of the accumulation of subscribers...... as Self Configurable Distributed Antenna System (SCIDAS)....

  1. Factors associated with online victimisation among Malaysian adolescents who use social networking sites: a cross-sectional study.

    Science.gov (United States)

    Marret, Mary J; Choo, Wan Yuen

    2017-06-30

    To determine the prevalence of online interpersonal victimisation and its association with patterns of social networking site (SNS) use, offline victimisation, offline perpetration and parental conflict among Malaysian adolescents using SNS. A cross-sectional study of students from randomly selected public secondary schools in the state of Negeri Sembilan was conducted using an anonymous self-administered questionnaire. The questionnaire examined patterns of SNS use and included measures of online victimisation, online perpetration, offline victimisation and parental conflict. A response rate of 91% from a total of 1634 yielded a sample of 1487 students between 15 years and 16 years of age. Ninety-two per cent of respondents had used at least one SNS. More than half of SNS users (52.2%) reported experiences of online victimisation over the past 12 months. Boys were significantly more likely to experience online harassment compared with girls (52.2% vs 43.3%, pgender differences in experiences of unwanted sexual solicitation. Adolescents who engaged in perpetration behaviours online had almost six times higher odds of reporting frequent online victimisation compared with online behaviours involving personal disclosure. There was a significant dose-response relationship between engagement in multiple types of online behaviour and the risk of frequent online victimisation. Both online and offline perpetrations were associated with an increased risk of victimisation. Those who were victimised offline or experienced parental conflict were twice as likely to report online victimisation. Interventions to prevent online electronic aggression should target perpetration behaviour both online and offline. Youth should be equipped with skills in communication and decision-making in relationships that can be applied across a spectrum of contexts both online and offline. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All

  2. On-Line Tracking Controller for Brushless DC Motor Drives Using Artificial Neural Networks

    Science.gov (United States)

    Rubaai, Ahmed

    1996-01-01

    A real-time control architecture is developed for time-varying nonlinear brushless dc motors operating in a high performance drives environment. The developed control architecture possesses the capabilities of simultaneous on-line identification and control. The dynamics of the motor are modeled on-line and controlled using an artificial neural network, as the system runs. The control architecture combines the experience and dependability of adaptive tracking systems with potential and promise of the neural computing technology. The sensitivity of real-time controller to parametric changes that occur during training is investigated. Such changes are usually manifested by rapid changes in the load of the brushless motor drives. This sudden change in the external load is simulated for the sigmoidal and sinusoidal reference tracks. The ability of the neuro-controller to maintain reasonable tracking accuracy in the presence of external noise is also verified for a number of desired reference trajectories.

  3. Use of online social networking sites among pre-service information technology teachers

    Directory of Open Access Journals (Sweden)

    Elif Buğra Kuzu

    2013-12-01

    Full Text Available The current study aimed to investigate the current status and perceptions of pre-service information technology (IT teachers regarding the use of online social networking sites (SNSs. The investigation was further supported through participant feedback regarding the design and implementation of a blended learning environment to embrace online SNSs in instructional settings. The study had a qualitative nature and employed a focus group interview to collect data. Participants were ten fourth graders who were randomly selected from voluntary undergraduate students enrolled at an IT education department of a Turkish state university. Researchers resorted to content analysis through an inductive coding process, provided themes addressing student perceptions and needs, and proposed implications and suggestions for further instructional practices.

  4. The Role of online Social networks in Teaching and Learning a foreign Language : Effects on Learning Process and Outcome

    NARCIS (Netherlands)

    Akbari, E.|info:eu-repo/dai/nl/345517180

    2016-01-01

    Today, online social networks are among the most important communications tools, connecting millions of people with common interests and ideas all over the world (Zaidieh, 2012). The rapid proliferation of Internet services has facilitated access to these networks not only via computers, but also

  5. An Analysis of Density and Degree-Centrality According to the Social Networking Structure Formed in an Online Learning Environment

    Science.gov (United States)

    Ergün, Esin; Usluel, Yasemin Koçak

    2016-01-01

    In this study, we assessed the communication structure in an educational online learning environment using social network analysis (SNA). The communication structure was examined with respect to time, and instructor's participation. The course was implemented using ELGG, a network learning environment, blended with face-to-face sessions over a…

  6. The new alchemy: Online networking, data sharing and research activity distribution tools for scientists.

    Science.gov (United States)

    Williams, Antony J; Peck, Lou; Ekins, Sean

    2017-01-01

    There is an abundance of free online tools accessible to scientists and others that can be used for online networking, data sharing and measuring research impact. Despite this, few scientists know how these tools can be used or fail to take advantage of using them as an integrated pipeline to raise awareness of their research outputs. In this article, the authors describe their experiences with these tools and how they can make best use of them to make their scientific research generally more accessible, extending its reach beyond their own direct networks, and communicating their ideas to new audiences. These efforts have the potential to drive science by sparking new collaborations and interdisciplinary research projects that may lead to future publications, funding and commercial opportunities. The intent of this article is to: describe some of these freely accessible networking tools and affiliated products; demonstrate from our own experiences how they can be utilized effectively; and, inspire their adoption by new users for the benefit of science.

  7. An online database for informing ecological network models: http://kelpforest.ucsc.edu

    Science.gov (United States)

    Beas-Luna, Rodrigo; Tinker, M. Tim; Novak, Mark; Carr, Mark H.; Black, August; Caselle, Jennifer E.; Hoban, Michael; Malone, Dan; Iles, Alison C.

    2014-01-01

    Ecological network models and analyses are recognized as valuable tools for understanding the dynamics and resiliency of ecosystems, and for informing ecosystem-based approaches to management. However, few databases exist that can provide the life history, demographic and species interaction information necessary to parameterize ecological network models. Faced with the difficulty of synthesizing the information required to construct models for kelp forest ecosystems along the West Coast of North America, we developed an online database (http://kelpforest.ucsc.edu/) to facilitate the collation and dissemination of such information. Many of the database's attributes are novel yet the structure is applicable and adaptable to other ecosystem modeling efforts. Information for each taxonomic unit includes stage-specific life history, demography, and body-size allometries. Species interactions include trophic, competitive, facilitative, and parasitic forms. Each data entry is temporally and spatially explicit. The online data entry interface allows researchers anywhere to contribute and access information. Quality control is facilitated by attributing each entry to unique contributor identities and source citations. The database has proven useful as an archive of species and ecosystem-specific information in the development of several ecological network models, for informing management actions, and for education purposes (e.g., undergraduate and graduate training). To facilitate adaptation of the database by other researches for other ecosystems, the code and technical details on how to customize this database and apply it to other ecosystems are freely available and located at the following link (https://github.com/kelpforest-cameo/data​baseui).

  8. From Subjective Trust to Objective Trustworthiness in On-line Social Networks: Overview and Challenges

    Directory of Open Access Journals (Sweden)

    David Zejda

    2010-04-01

    Full Text Available Nowadays dozens of people share their content in the current Web 2.0 space, talk with friends in social networking sites such as Facebook and live on the Net in many other ways. They do all this quite naturally, forgetting the healthy cautiousness sometimes. In real life we rely on trusted people. Do we know how to reflect real-world trust mechanisms into on-line social software? In the article we focused to bring overview on state of the art in main ideas behind a trust processing in online social networking systems. What are common sources of subjective trust, how the trust emerges and what are the sources of trust dynamics? How can be trust captured into the systems, how can be explicit trust processed to infer indirect trust, the trust between users who do not know each other? And what are the ways to infer objective metrics of trust, the reputation or trustworthiness? Finally, we point out selected challenges related to the trust in current highly dynamic social networks.

  9. An Online Database for Informing Ecological Network Models: http://kelpforest.ucsc.edu

    Science.gov (United States)

    Beas-Luna, Rodrigo; Novak, Mark; Carr, Mark H.; Tinker, Martin T.; Black, August; Caselle, Jennifer E.; Hoban, Michael; Malone, Dan; Iles, Alison

    2014-01-01

    Ecological network models and analyses are recognized as valuable tools for understanding the dynamics and resiliency of ecosystems, and for informing ecosystem-based approaches to management. However, few databases exist that can provide the life history, demographic and species interaction information necessary to parameterize ecological network models. Faced with the difficulty of synthesizing the information required to construct models for kelp forest ecosystems along the West Coast of North America, we developed an online database (http://kelpforest.ucsc.edu/) to facilitate the collation and dissemination of such information. Many of the database's attributes are novel yet the structure is applicable and adaptable to other ecosystem modeling efforts. Information for each taxonomic unit includes stage-specific life history, demography, and body-size allometries. Species interactions include trophic, competitive, facilitative, and parasitic forms. Each data entry is temporally and spatially explicit. The online data entry interface allows researchers anywhere to contribute and access information. Quality control is facilitated by attributing each entry to unique contributor identities and source citations. The database has proven useful as an archive of species and ecosystem-specific information in the development of several ecological network models, for informing management actions, and for education purposes (e.g., undergraduate and graduate training). To facilitate adaptation of the database by other researches for other ecosystems, the code and technical details on how to customize this database and apply it to other ecosystems are freely available and located at the following link (https://github.com/kelpforest-cameo/databaseui). PMID:25343723

  10. Online dimensionality reduction using competitive learning and Radial Basis Function network.

    Science.gov (United States)

    Tomenko, Vladimir

    2011-06-01

    The general purpose dimensionality reduction method should preserve data interrelations at all scales. Additional desired features include online projection of new data, processing nonlinearly embedded manifolds and large amounts of data. The proposed method, called RBF-NDR, combines these features. RBF-NDR is comprised of two modules. The first module learns manifolds by utilizing modified topology representing networks and geodesic distance in data space and approximates sampled or streaming data with a finite set of reference patterns, thus achieving scalability. Using input from the first module, the dimensionality reduction module constructs mappings between observation and target spaces. Introduction of specific loss function and synthesis of the training algorithm for Radial Basis Function network results in global preservation of data structures and online processing of new patterns. The RBF-NDR was applied for feature extraction and visualization and compared with Principal Component Analysis (PCA), neural network for Sammon's projection (SAMANN) and Isomap. With respect to feature extraction, the method outperformed PCA and yielded increased performance of the model describing wastewater treatment process. As for visualization, RBF-NDR produced superior results compared to PCA and SAMANN and matched Isomap. For the Topic Detection and Tracking corpus, the method successfully separated semantically different topics. Copyright © 2011 Elsevier Ltd. All rights reserved.

  11. An online database for informing ecological network models: http://kelpforest.ucsc.edu.

    Science.gov (United States)

    Beas-Luna, Rodrigo; Novak, Mark; Carr, Mark H; Tinker, Martin T; Black, August; Caselle, Jennifer E; Hoban, Michael; Malone, Dan; Iles, Alison

    2014-01-01

    Ecological network models and analyses are recognized as valuable tools for understanding the dynamics and resiliency of ecosystems, and for informing ecosystem-based approaches to management. However, few databases exist that can provide the life history, demographic and species interaction information necessary to parameterize ecological network models. Faced with the difficulty of synthesizing the information required to construct models for kelp forest ecosystems along the West Coast of North America, we developed an online database (http://kelpforest.ucsc.edu/) to facilitate the collation and dissemination of such information. Many of the database's attributes are novel yet the structure is applicable and adaptable to other ecosystem modeling efforts. Information for each taxonomic unit includes stage-specific life history, demography, and body-size allometries. Species interactions include trophic, competitive, facilitative, and parasitic forms. Each data entry is temporally and spatially explicit. The online data entry interface allows researchers anywhere to contribute and access information. Quality control is facilitated by attributing each entry to unique contributor identities and source citations. The database has proven useful as an archive of species and ecosystem-specific information in the development of several ecological network models, for informing management actions, and for education purposes (e.g., undergraduate and graduate training). To facilitate adaptation of the database by other researches for other ecosystems, the code and technical details on how to customize this database and apply it to other ecosystems are freely available and located at the following link (https://github.com/kelpforest-cameo/databaseui).

  12. Sharing data for public health research by members of an international online diabetes social network.

    Science.gov (United States)

    Weitzman, Elissa R; Adida, Ben; Kelemen, Skyler; Mandl, Kenneth D

    2011-04-27

    Surveillance and response to diabetes may be accelerated through engaging online diabetes social networks (SNs) in consented research. We tested the willingness of an online diabetes community to share data for public health research by providing members with a privacy-preserving social networking software application for rapid temporal-geographic surveillance of glycemic control. SN-mediated collection of cross-sectional, member-reported data from an international online diabetes SN entered into a software application we made available in a "Facebook-like" environment to enable reporting, charting and optional sharing of recent hemoglobin A1c values through a geographic display. Self-enrollment by 17% (n = 1,136) of n = 6,500 active members representing 32 countries and 50 US states. Data were current with 83.1% of most recent A1c values reported obtained within the past 90 days. Sharing was high with 81.4% of users permitting data donation to the community display. 34.1% of users also displayed their A1cs on their SN profile page. Users selecting the most permissive sharing options had a lower average A1c (6.8%) than users not sharing with the community (7.1%, p = .038). 95% of users permitted re-contact. Unadjusted aggregate A1c reported by US users closely resembled aggregate 2007-2008 NHANES estimates (respectively, 6.9% and 6.9%, p = 0.85). Success within an early adopter community demonstrates that online SNs may comprise efficient platforms for bidirectional communication with and data acquisition from disease populations. Advancing this model for cohort and translational science and for use as a complementary surveillance approach will require understanding of inherent selection and publication (sharing) biases in the data and a technology model that supports autonomy, anonymity and privacy.

  13. Social Network Analysis of Elders' Health Literacy and their Use of Online Health Information.

    Science.gov (United States)

    Jang, Haeran; An, Ji-Young

    2014-07-01

    Utilizing social network analysis, this study aimed to analyze the main keywords in the literature regarding the health literacy of and the use of online health information by aged persons over 65. Medical Subject Heading keywords were extracted from articles on the PubMed database of the National Library of Medicine. For health literacy, 110 articles out of 361 were initially extracted. Seventy-one keywords out of 1,021 were finally selected after removing repeated keywords and applying pruning. Regarding the use of online health information, 19 articles out of 26 were selected. One hundred forty-four keywords were initially extracted. After removing the repeated keywords, 74 keywords were finally selected. Health literacy was found to be strongly connected with 'Health knowledge, attitudes, practices' and 'Patient education as topic.' 'Computer literacy' had strong connections with 'Internet' and 'Attitude towards computers.' 'Computer literacy' was connected to 'Health literacy,' and was studied according to the parameters 'Attitude towards health' and 'Patient education as topic.' The use of online health information was strongly connected with 'Health knowledge, attitudes, practices,' 'Consumer health information,' 'Patient education as topic,' etc. In the network, 'Computer literacy' was connected with 'Health education,' 'Patient satisfaction,' 'Self-efficacy,' 'Attitude to computer,' etc. Research on older citizens' health literacy and their use of online health information was conducted together with study of computer literacy, patient education, attitude towards health, health education, patient satisfaction, etc. In particular, self-efficacy was noted as an important keyword. Further research should be conducted to identify the effective outcomes of self-efficacy in the area of interest.

  14. Sharing data for public health research by members of an international online diabetes social network.

    Directory of Open Access Journals (Sweden)

    Elissa R Weitzman

    2011-04-01

    Full Text Available Surveillance and response to diabetes may be accelerated through engaging online diabetes social networks (SNs in consented research. We tested the willingness of an online diabetes community to share data for public health research by providing members with a privacy-preserving social networking software application for rapid temporal-geographic surveillance of glycemic control.SN-mediated collection of cross-sectional, member-reported data from an international online diabetes SN entered into a software application we made available in a "Facebook-like" environment to enable reporting, charting and optional sharing of recent hemoglobin A1c values through a geographic display. Self-enrollment by 17% (n = 1,136 of n = 6,500 active members representing 32 countries and 50 US states. Data were current with 83.1% of most recent A1c values reported obtained within the past 90 days. Sharing was high with 81.4% of users permitting data donation to the community display. 34.1% of users also displayed their A1cs on their SN profile page. Users selecting the most permissive sharing options had a lower average A1c (6.8% than users not sharing with the community (7.1%, p = .038. 95% of users permitted re-contact. Unadjusted aggregate A1c reported by US users closely resembled aggregate 2007-2008 NHANES estimates (respectively, 6.9% and 6.9%, p = 0.85.Success within an early adopter community demonstrates that online SNs may comprise efficient platforms for bidirectional communication with and data acquisition from disease populations. Advancing this model for cohort and translational science and for use as a complementary surveillance approach will require understanding of inherent selection and publication (sharing biases in the data and a technology model that supports autonomy, anonymity and privacy.

  15. Social network analysis as a method for analyzing interaction in collaborative online learning environments

    Directory of Open Access Journals (Sweden)

    Patricia Rice Doran

    2011-12-01

    Full Text Available Social network analysis software such as NodeXL has been used to describe participation and interaction in numerous social networks, but it has not yet been widely used to examine dynamics in online classes, where participation is frequently required rather than optional and participation patterns may be impacted by the requirements of the class, the instructor’s activities, or participants’ intrinsic engagement with the subject matter. Such social network analysis, which examines the dynamics and interactions among groups of participants in a social network or learning group, can be valuable in programs focused on teaching collaborative and communicative skills, including teacher preparation programs. Applied to these programs, social network analysis can provide information about instructional practices likely to facilitate student interaction and collaboration across diverse student populations. This exploratory study used NodeXL to visualize students’ participation in an online course, with the goal of identifying (1 ways in which NodeXL could be used to describe patterns in participant interaction within an instructional setting and (2 identifying specific patterns in participant interaction among students in this particular course. In this sample, general education teachers demonstrated higher measures of connection and interaction with other participants than did those from specialist (ESOL or special education backgrounds, and tended to interact more frequently with all participants than the majority of participants from specialist backgrounds. We recommend further research to delineate specific applications of NodeXL within an instructional context, particularly to identify potential patterns in student participation based on variables such as gender, background, cultural and linguistic heritage, prior training and education, and prior experience so that instructors can ensure their practice helps to facilitate student interaction

  16. Using the Internet, Online Social Networks and Potentially Incurred Risk: Student Opinions

    Directory of Open Access Journals (Sweden)

    Gintautė Žibėnienė

    2013-08-01

    Full Text Available Regulation of harmful content on the Internet is a soaring problem in the expansion of the information society, and it is being discussed in different European countries. Therefore, it is important to discuss the issue of being safe online: to do research on what children think about when using the Internet, threats experienced while online, to discuss ways of recognising and protecting children from online threats (such as cyber bullying, bullying, abuse, temptations with purpose of sexual harassment, leaking of personal information, spreading, harmful and illegal Internet content, etc.. The research objective of this paper is to present the opinion of gymnasium students on using the Internet, online social networks and likely experienced threats. The methodology—opinion research of the gymnasium students, which was carried out 17–21 December 2012; an analysis of professional target publications and a questionnaire survey were also applied. Analysis of the research findings was based on the analysis methods of quantity analysis (descriptive and analysis of quality content. Statistical findings were analysed applying the software “Statistical Package for the Social Sciences (SPSS 21.0 for Windows.” According to the research of student opinion, it was revealed that the most common student online activities are browsing of chat websites, exchange of videos and other material, viewing, listening and participating in social networks, whereas erotica and viewing of pornography are the rarest activities and are unimportant for students. Online social networks are especially popular among students, as most interviewed students (95.3% have their own profile in social networks. Students mostly visit social networks to communicate, to make friends (77.1% of respondents, however, every second student (60.7% visits them just to spend time, which can be assumed about the problems of students’ leisure time. The vast majority of students think that

  17. Exploring the presentation of HPV information online: A semantic network analysis of websites.

    Science.gov (United States)

    Ruiz, Jeanette B; Barnett, George A

    2015-06-26

    Negative vaccination-related information online leads some to opt out of recommended vaccinations. To determine how HPV vaccine information is presented online and what concepts co-occur. A semantic network analysis of the words in first-page Google search results was conducted using three negative, three neutral, and three positive search terms for 10 base concepts such as HPV vaccine, and HPV immunizations. In total, 223 of the 300 websites retrieved met inclusion requirements. Website information was analyzed using network statistics to determine what words most frequently appear, which words co-occur, and the sentiment of the words. High levels of word interconnectivity were found suggesting a rich set of semantic links and a very integrated set of concepts. Limited number of words held centrality indicating limited concept prominence. This dense network signifies concepts that are well connected. Negative words were most prevalent and were associated with describing the HPV vaccine's side-effects as well as the negative effects of HPV and cervical cancer. A smaller cluster focuses on reporting negative vaccine side-effects. Clustering shows the words women and girls closely located to the words sexually, virus, and infection. Information about the HPV vaccine online centered on a limited number of concepts. HPV vaccine benefits as well as the risks of HPV, including severity and susceptibility, were centrally presented. Word cluster results imply that HPV vaccine information for women and girls is discussed in more sexual terms than for men and boys. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. Effects of Social Network Exposure on Nutritional Learning: Development of an Online Educational Platform.

    Science.gov (United States)

    Dagan, Noa; Beskin, Daniel; Brezis, Mayer; Reis, Ben Y

    2015-10-05

    Social networking sites (SNSs) such as Facebook have the potential to enhance online public health interventions, in part, as they provide social exposure and reinforcement. The objective of the study was to evaluate whether social exposure provided by SNSs enhances the effects of online public health interventions. As a sample intervention, we developed Food Hero, an online platform for nutritional education in which players feed a virtual character according to their own nutritional needs and complete a set of virtual sport challenges. The platform was developed in 2 versions: a "private version" in which a user can see only his or her own score, and a "social version" in which a user can see other players' scores, including preexisting Facebook friends. We assessed changes in participants' nutritional knowledge using 4 quiz scores and 3 menu-assembly scores. Monitoring feeding and exercising attempts assessed engagement with the platform. The 2 versions of the platform were randomly assigned between a study group (30 members receiving the social version) and a control group (33 members, private version). The study group's performance on the quizzes gradually increased over time, relative to that of the control group, becoming significantly higher by the fourth quiz (P=.02). Furthermore, the study group's menu-assembly scores improved over time compared to the first score, whereas the control group's performance deteriorated. Study group members spent an average of 3:40 minutes assembling each menu compared to 2:50 minutes in the control group, and performed an average of 1.58 daily sport challenges, compared to 1.21 in the control group (P=.03). This work focused on isolating the SNSs' social effects in order to help guide future online interventions. Our results indicate that the social exposure provided by SNSs is associated with increased engagement and learning in an online nutritional educational platform.

  19. Selected Flight Test Results for Online Learning Neural Network-Based Flight Control System

    Science.gov (United States)

    Williams-Hayes, Peggy S.

    2004-01-01

    The NASA F-15 Intelligent Flight Control System project team developed a series of flight control concepts designed to demonstrate neural network-based adaptive controller benefits, with the objective to develop and flight-test control systems using neural network technology to optimize aircraft performance under nominal conditions and stabilize the aircraft under failure conditions. This report presents flight-test results for an adaptive controller using stability and control derivative values from an online learning neural network. A dynamic cell structure neural network is used in conjunction with a real-time parameter identification algorithm to estimate aerodynamic stability and control derivative increments to baseline aerodynamic derivatives in flight. This open-loop flight test set was performed in preparation for a future phase in which the learning neural network and parameter identification algorithm output would provide the flight controller with aerodynamic stability and control derivative updates in near real time. Two flight maneuvers are analyzed - pitch frequency sweep and automated flight-test maneuver designed to optimally excite the parameter identification algorithm in all axes. Frequency responses generated from flight data are compared to those obtained from nonlinear simulation runs. Flight data examination shows that addition of flight-identified aerodynamic derivative increments into the simulation improved aircraft pitch handling qualities.

  20. Online social networks for crowdsourced multimedia-involved behavioral testing: An empirical study

    Directory of Open Access Journals (Sweden)

    Jun-Ho eChoi

    2016-01-01

    Full Text Available Online social networks have emerged as effective crowdsourcing media to recruit participants in recent days. However, issues regarding how to effectively exploit them have not been adequately addressed yet. In this paper, we investigate the reliability and effectiveness of multimedia-involved behavioral testing via social network-based crowdsourcing, especially focused on Facebook as a medium to recruit participants. We conduct a crowdsourcing-based experiment for a music recommendation problem. It is shown that different advertisement methods yield different degrees of efficiency and there exist significant differences in behavioral patterns across different genders and different age groups. In addition, we perform a comparison of our experiment with other multimedia-involved crowdsourcing experiments built on Amazon Mechanical Turk (MTurk, which suggests that crowdsourcing-based experiments using social networks for recruitment can achieve comparable efficiency. Based on the analysis results, advantages and disadvantages of social network-based crowdsourcing and suggestions for successful experiments are also discussed. We conclude that social networks have the potential to support multimedia-involved behavioral tests to gather in-depth data even for long-term periods.

  1. Online Social Networks for Crowdsourced Multimedia-Involved Behavioral Testing: An Empirical Study

    Science.gov (United States)

    Choi, Jun-Ho; Lee, Jong-Seok

    2016-01-01

    Online social networks have emerged as effective crowdsourcing media to recruit participants in recent days. However, issues regarding how to effectively exploit them have not been adequately addressed yet. In this paper, we investigate the reliability and effectiveness of multimedia-involved behavioral testing via social network-based crowdsourcing, especially focused on Facebook as a medium to recruit participants. We conduct a crowdsourcing-based experiment for a music recommendation problem. It is shown that different advertisement methods yield different degrees of efficiency and there exist significant differences in behavioral patterns across different genders and different age groups. In addition, we perform a comparison of our experiment with other multimedia-involved crowdsourcing experiments built on Amazon Mechanical Turk (MTurk), which suggests that crowdsourcing-based experiments using social networks for recruitment can achieve comparable efficiency. Based on the analysis results, advantages and disadvantages of social network-based crowdsourcing and suggestions for successful experiments are also discussed. We conclude that social networks have the potential to support multimedia-involved behavioral tests to gather in-depth data even for long-term periods. PMID:26793137

  2. Online Social Networks for Crowdsourced Multimedia-Involved Behavioral Testing: An Empirical Study.

    Science.gov (United States)

    Choi, Jun-Ho; Lee, Jong-Seok

    2015-01-01

    Online social networks have emerged as effective crowdsourcing media to recruit participants in recent days. However, issues regarding how to effectively exploit them have not been adequately addressed yet. In this paper, we investigate the reliability and effectiveness of multimedia-involved behavioral testing via social network-based crowdsourcing, especially focused on Facebook as a medium to recruit participants. We conduct a crowdsourcing-based experiment for a music recommendation problem. It is shown that different advertisement methods yield different degrees of efficiency and there exist significant differences in behavioral patterns across different genders and different age groups. In addition, we perform a comparison of our experiment with other multimedia-involved crowdsourcing experiments built on Amazon Mechanical Turk (MTurk), which suggests that crowdsourcing-based experiments using social networks for recruitment can achieve comparable efficiency. Based on the analysis results, advantages and disadvantages of social network-based crowdsourcing and suggestions for successful experiments are also discussed. We conclude that social networks have the potential to support multimedia-involved behavioral tests to gather in-depth data even for long-term periods.

  3. Understanding Health Professionals' Informal Learning in Online Social Networks: A Cross-Sectional Survey.

    Science.gov (United States)

    Li, Xin; Verspoor, Karin; Gray, Kathleen; Barnett, Stephen

    2017-01-01

    Online social networks (OSNs) enable health professionals to learn informally, for example by sharing medical knowledge, or discussing practice management challenges and clinical issues. Understanding how learning occurs in OSNs is necessary to better support this type of learning. Through a cross-sectional survey, this study found that learning interaction in OSNs is low in general, with a small number of active users. Some health professionals actively used OSNs to support their practice, including sharing practical and experiential knowledge, benchmarking themselves, and to keep up-to-date on policy, advanced information and news in the field. These health professionals had an overall positive learning experience in OSNs.

  4. Flight envelope protection of aircraft using adaptive neural network and online linearisation

    Science.gov (United States)

    Shin, Hohyun; Kim, Youdan

    2016-03-01

    Flight envelope protection algorithm is proposed to improve the safety of an aircraft. Flight envelope protection systems find the control inputs to prevent an aircraft from exceeding structure/aerodynamic limits and maximum control surface deflections. The future values of state variables are predicted using the current states and control inputs based on linearised aircraft model. To apply the envelope protection algorithm for the wide envelope of the aircraft, online linearisation is adopted. Finally, the flight envelope protection system is designed using adaptive neural network and least-squares method. Numerical simulations are conducted to verify the performance of the proposed scheme.

  5. An Introduction to Models of Online Peer-to-Peer Social Networking

    CERN Document Server

    Kesidis, George

    2010-01-01

    This book concerns peer-to-peer applications and mechanisms operating on the Internet, particularly those that are not fully automated and involve significant human interaction. So, the realm of interest is the intersection of distributed systems and online social networking. Generally, simple models are described to clarify the ideas. Beginning with short overviews of caching, graph theory and game theory, we cover the basic ideas of structured and unstructured search. We then describe a simple framework for reputations and for iterated referrals and consensus. This framework is applied to a

  6. Rumor spreading in online social networks by considering the bipolar social reinforcement

    Science.gov (United States)

    Ma, Jing; Li, Dandan; Tian, Zihao

    2016-04-01

    Considering the bipolar social reinforcement which includes positive and negative effects, in this paper we explore the rumor spreading dynamics in online social networks. By means of the generation function and cavity method developed from statistical physics of disordered system, the rumor spreading threshold can be theoretically drawn. Simulation results indicate that decreasing the positive reinforcement factor or increasing the negative reinforcement factor can suppress the rumor spreading effectively. By analyzing the topological properties of the real world social network, we find that the nodes with lower degree usually have smaller weight. However, the nodes with lower degree may have larger k-shell. In order to curb rumor spreading, some control strategies that are based on the nodes' degree, k-shell and weight are presented. By comparison, we show that controlling those nodes that have larger degree or weight are two effective strategies to prevent the rumor spreading.

  7. Greek Civil Society’s Online Alternative Networks as Emergent Resilience Strategies in Time of Crisis

    Directory of Open Access Journals (Sweden)

    Maria Zafiropoulou

    2016-12-01

    Full Text Available The use of new communications technologies and social media, in Greece, during the time of crisis, has led to the development of numerous online informal Civil Society Networks (CSNs (i.e. networking-building platforms, self - organized groups in Facebook, forums, exchange platforms proposing a rethinking of the status quo of formal civil organizations. This research, utilizing the methodology of discourse analysis, aims at summarizing the rise of these networks in Greece that incorporates both solidarity initiatives and autonomous political/economic spaces and identify the indicative predictive factors of their survival and growth. Some basic conclusions that have been drawn through this research is that alternative online networks can be proven as indicative sign of the social dynamism of a given period but in order to be resilient and sustainable they should develop focal points of physical reference, pursue national representation, focus mainly on monothematic goods/services and cultivate, in several cases, links with relevant social movements and local or national NGOs. A general induction through this research is that a CSN, during this current crisis, stands between two classical models of reference in a society seeking modernity and flexibility and can be considered as a proposed type of effective experimentation and mobilization that can pursue common social goals and serve needs of deprived people. Some issues that still remain underexplored and need further elaboration are social and political identity of participants, the potential links with local, national and international communities, the functional balance between structure and flexibility as well as the efficient distribution of energy between solidarity and protest.

  8. [Semantic Network Analysis of Online News and Social Media Text Related to Comprehensive Nursing Care Service].

    Science.gov (United States)

    Kim, Minji; Choi, Mona; Youm, Yoosik

    2017-12-01

    As comprehensive nursing care service has gradually expanded, it has become necessary to explore the various opinions about it. The purpose of this study is to explore the large amount of text data regarding comprehensive nursing care service extracted from online news and social media by applying a semantic network analysis. The web pages of the Korean Nurses Association (KNA) News, major daily newspapers, and Twitter were crawled by searching the keyword 'comprehensive nursing care service' using Python. A morphological analysis was performed using KoNLPy. Nodes on a 'comprehensive nursing care service' cluster were selected, and frequency, edge weight, and degree centrality were calculated and visualized with Gephi for the semantic network. A total of 536 news pages and 464 tweets were analyzed. In the KNA News and major daily newspapers, 'nursing workforce' and 'nursing service' were highly rated in frequency, edge weight, and degree centrality. On Twitter, the most frequent nodes were 'National Health Insurance Service' and 'comprehensive nursing care service hospital.' The nodes with the highest edge weight were 'national health insurance,' 'wards without caregiver presence,' and 'caregiving costs.' 'National Health Insurance Service' was highest in degree centrality. This study provides an example of how to use atypical big data for a nursing issue through semantic network analysis to explore diverse perspectives surrounding the nursing community through various media sources. Applying semantic network analysis to online big data to gather information regarding various nursing issues would help to explore opinions for formulating and implementing nursing policies. © 2017 Korean Society of Nursing Science

  9. Imbalanced functional link between executive control network and reward network explain the online-game seeking behaviors in Internet gaming disorder.

    Science.gov (United States)

    Dong, Guangheng; Lin, Xiao; Hu, Yanbo; Xie, Chunming; Du, Xiaoxia

    2015-03-17

    Literatures have shown that Internet gaming disorder (IGD) subjects show impaired executive control and enhanced reward sensitivities than healthy controls. However, how these two networks jointly affect the valuation process and drive IGD subjects' online-game-seeking behaviors remains unknown. Thirty-five IGD and 36 healthy controls underwent a resting-states scan in the MRI scanner. Functional connectivity (FC) was examined within control and reward network seeds regions, respectively. Nucleus accumbens (NAcc) was selected as the node to find the interactions between these two networks. IGD subjects show decreased FC in the executive control network and increased FC in the reward network when comparing with the healthy controls. When examining the correlations between the NAcc and the executive control/reward networks, the link between the NAcc - executive control network is negatively related with the link between NAcc - reward network. The changes (decrease/increase) in IGD subjects' brain synchrony in control/reward networks suggest the inefficient/overly processing within neural circuitry underlying these processes. The inverse proportion between control network and reward network in IGD suggest that impairments in executive control lead to inefficient inhibition of enhanced cravings to excessive online game playing. This might shed light on the mechanistic understanding of IGD.

  10. Muslim Young People Online: “Acts of Citizenship” in Socially Networked Spaces

    Directory of Open Access Journals (Sweden)

    Amelia Johns

    2014-08-01

    Full Text Available This paper reviews the current literature regarding Muslim young people’s online social networking and participatory practices with the aim of examining whether these practices open up new spaces of civic engagement and political participation. The paper focuses on the experiences of young Muslims living in western societies, where, since September 11, the ability to assert claims as citizens in the public arena has diminished. The paper draws upon Isin & Nielsen’s (2008 “acts of citizenship” to define the online practices of many Muslim youth, for whom the internet provides a space where new performances of citizenship are enacted outside of formal citizenship rights and spaces of participation. These “acts" are evaluated in light of theories which articulate the changing nature of publics and the public sphere in a digital era. The paper will use this conceptual framework in conjunction with the literature review to explore whether virtual, online spaces offer young Muslims an opportunity to create a more inclusive discursive space to interact with co-citizens, engage with social and political issues and assert their citizen rights than is otherwise afforded by formal political structures; a need highlighted by policies which target minority Muslim young people for greater civic participation but which do not reflect the interests and values of Muslim young people.

  11. Research on Linear Wireless Sensor Networks Used for Online Monitoring of Rolling Bearing in Freight Train

    International Nuclear Information System (INIS)

    Wang Nan; Meng Qingfeng; Zheng Bin; Li Tong; Ma Qinghai

    2011-01-01

    This paper presents a Wireless Sensor Networks (WSNs) technique for the purpose of on-line monitoring of rolling bearing in freight train. A new technical scheme including the arrangements of sensors, the design of sensor nodes and base station, routing protocols, signal acquirement, processing and transmission is described, and an on-line monitoring system is established. Considering the approximately linear arrangements of cars and the running state of freight train, a linear topology structure of WSNs is adopted and five linear routing protocols are discussed in detail as to obtain the desired minimum energy consumption of WSNs. By analysing the simulation results, an optimal multi-hop routing protocol named sub-section routing protocol according to equal distance is adopted, in which all sensor nodes are divided into different groups according to the equal transmission distance, the optimal transmission distance and number of hops of routing protocol are also studied. We know that the communication consumes significant power in WSNs, so, in order to save the limit power supply of WSNs, the data compression and coding scheme based on lifting integer wavelet and embedded zerotree wavelet (EZW) algorithms is studied to reduce the amounts of data transmitted. The experimental results of rolling bearing have been given at last to verify the effectiveness of data compression algorithm. The on-line monitoring system of rolling bearing in freight train will be applied to actual application in the near future.

  12. Analyzing the Impact of Storage Shortage on Data Availability in Decentralized Online Social Networks

    Directory of Open Access Journals (Sweden)

    Songling Fu

    2014-01-01

    Full Text Available Maintaining data availability is one of the biggest challenges in decentralized online social networks (DOSNs. The existing work often assumes that the friends of a user can always contribute to the sufficient storage capacity to store all data. However, this assumption is not always true in today’s online social networks (OSNs due to the fact that nowadays the users often use the smart mobile devices to access the OSNs. The limitation of the storage capacity in mobile devices may jeopardize the data availability. Therefore, it is desired to know the relation between the storage capacity contributed by the OSN users and the level of data availability that the OSNs can achieve. This paper addresses this issue. In this paper, the data availability model over storage capacity is established. Further, a novel method is proposed to predict the data availability on the fly. Extensive simulation experiments have been conducted to evaluate the effectiveness of the data availability model and the on-the-fly prediction.

  13. Analyzing the impact of storage shortage on data availability in decentralized online social networks.

    Science.gov (United States)

    Fu, Songling; He, Ligang; Liao, Xiangke; Li, Kenli; Huang, Chenlin

    2014-01-01

    Maintaining data availability is one of the biggest challenges in decentralized online social networks (DOSNs). The existing work often assumes that the friends of a user can always contribute to the sufficient storage capacity to store all data. However, this assumption is not always true in today's online social networks (OSNs) due to the fact that nowadays the users often use the smart mobile devices to access the OSNs. The limitation of the storage capacity in mobile devices may jeopardize the data availability. Therefore, it is desired to know the relation between the storage capacity contributed by the OSN users and the level of data availability that the OSNs can achieve. This paper addresses this issue. In this paper, the data availability model over storage capacity is established. Further, a novel method is proposed to predict the data availability on the fly. Extensive simulation experiments have been conducted to evaluate the effectiveness of the data availability model and the on-the-fly prediction.

  14. Socio-psychological factors influencing continuance intention of participants using online social networks to buy

    Directory of Open Access Journals (Sweden)

    Akwesi Assensoh-Kodua

    2015-09-01

    Full Text Available The purpose of this study is to investigate the influence of perceived trust (PT, social norm (SN, user satisfaction (US and perceived behavioural control (PBC from the perspective of online social networks (OSNs and how these factors influence continuance intention of OSN particpants who have ever been influenced to buy on this platform to continue buying from OSNs. Online survey was used to collect data from people who have ever used OSNs to buy, at least once. The WarpPLS 4.0 was used to analyse measurement and structural models resulting in significant evidence in support of PT, SN and US as predictors of OSN continuance intention, different from the traditional web-based transactions. For instance, trust in OSN is revealled to be based mainly on the degree of the social relations that users have with their vendors because they are members on the network, on top of their experiences of Web service use. US were influenced by PBC, while US also influenced SN and PT with PT exhibiting a strong relationship with SN. These results have practical implications for individuals desiring to engage in commercial activities on OSNs.

  15. Ethical considerations when employing fake identities in online social networks for research.

    Science.gov (United States)

    Elovici, Yuval; Fire, Michael; Herzberg, Amir; Shulman, Haya

    2014-12-01

    Online social networks (OSNs) have rapidly become a prominent and widely used service, offering a wealth of personal and sensitive information with significant security and privacy implications. Hence, OSNs are also an important--and popular--subject for research. To perform research based on real-life evidence, however, researchers may need to access OSN data, such as texts and files uploaded by users and connections among users. This raises significant ethical problems. Currently, there are no clear ethical guidelines, and researchers may end up (unintentionally) performing ethically questionable research, sometimes even when more ethical research alternatives exist. For example, several studies have employed "fake identities" to collect data from OSNs, but fake identities may be used for attacks and are considered a security issue. Is it legitimate to use fake identities for studying OSNs or for collecting OSN data for research? We present a taxonomy of the ethical challenges facing researchers of OSNs and compare different approaches. We demonstrate how ethical considerations have been taken into account in previous studies that used fake identities. In addition, several possible approaches are offered to reduce or avoid ethical misconducts. We hope this work will stimulate the development and use of ethical practices and methods in the research of online social networks.

  16. Identification of influential spreaders in online social networks using interaction weighted K-core decomposition method

    Science.gov (United States)

    Al-garadi, Mohammed Ali; Varathan, Kasturi Dewi; Ravana, Sri Devi

    2017-02-01

    Online social networks (OSNs) have become a vital part of everyday living. OSNs provide researchers and scientists with unique prospects to comprehend individuals on a scale and to analyze human behavioral patterns. Influential spreaders identification is an important subject in understanding the dynamics of information diffusion in OSNs. Targeting these influential spreaders is significant in planning the techniques for accelerating the propagation of information that is useful for various applications, such as viral marketing applications or blocking the diffusion of annoying information (spreading of viruses, rumors, online negative behaviors, and cyberbullying). Existing K-core decomposition methods consider links equally when calculating the influential spreaders for unweighted networks. Alternatively, the proposed link weights are based only on the degree of nodes. Thus, if a node is linked to high-degree nodes, then this node will receive high weight and is treated as an important node. Conversely, the degree of nodes in OSN context does not always provide accurate influence of users. In the present study, we improve the K-core method for OSNs by proposing a novel link-weighting method based on the interaction among users. The proposed method is based on the observation that the interaction of users is a significant factor in quantifying the spreading capability of user in OSNs. The tracking of diffusion links in the real spreading dynamics of information verifies the effectiveness of our proposed method for identifying influential spreaders in OSNs as compared with degree centrality, PageRank, and original K-core.

  17. Qualities and Inequalities in Online Social Networks through the Lens of the Generalized Friendship Paradox.

    Science.gov (United States)

    Momeni, Naghmeh; Rabbat, Michael

    2016-01-01

    The friendship paradox is the phenomenon that in social networks, people on average have fewer friends than their friends do. The generalized friendship paradox is an extension to attributes other than the number of friends. The friendship paradox and its generalized version have gathered recent attention due to the information they provide about network structure and local inequalities. In this paper, we propose several measures of nodal qualities which capture different aspects of their activities and influence in online social networks. Using these measures we analyse the prevalence of the generalized friendship paradox over Twitter and we report high levels of prevalence (up to over 90% of nodes). We contend that this prevalence of the friendship paradox and its generalized version arise because of the hierarchical nature of the connections in the network. This hierarchy is nested as opposed to being star-like. We conclude that these paradoxes are collective phenomena not created merely by a minority of well-connected or high-attribute nodes. Moreover, our results show that a large fraction of individuals can experience the generalized friendship paradox even in the absence of a significant correlation between degrees and attributes.

  18. 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.

  19. Online network of subspecialty aortic disease experts: Impact of "cloud" technology on management of acute aortic emergencies.

    Science.gov (United States)

    Schoenhagen, Paul; Roselli, Eric E; Harris, C Martin; Eagleton, Matthew; Menon, Venu

    2016-07-01

    For the management of acute aortic syndromes, regional treatment networks have been established to coordinate diagnosis and treatment between local emergency rooms and central specialized centers. Triage of acute aortic syndromes requires definitive imaging, resulting in complex data files. Modern information technology network structures, specifically "cloud" technology, coupled with mobile communication, increasingly support sharing of these data in a network of experts using mobile, online access and communication. Although this network is technically complex, the potential benefit of online sharing of data files between professionals at multiple locations within a treatment network appear obvious; however, clinical experience is limited, and further evaluation is needed. Copyright © 2016 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.

  20. The use of assisted performance within an online social network to develop reflective reasoning in undergraduate physiotherapy students.

    Science.gov (United States)

    Rowe, Michael

    2012-01-01

    The development of practice knowledge is an important component of clinical education and reflective reasoning is known to play a role in its development. Online social networks may have some potential for developing practice knowledge by providing tools for clinical educators to guide students' reasoning practices. To determine if an online social network could be used to facilitate reflective reasoning in clinical contexts, as it relates to developing practice knowledge. The study was conducted within a South African university, physiotherapy department, using an online social network to facilitate engagement. Tharp and Gallimore's theory of assisted performance was used as a framework to conduct qualitative analysis of students' reflective blog posts within the network. The lecturer was able to use strategies within the assisted performance framework to facilitate reflection among students. These included modelling, contingency management, feedback, instruction, questioning and cognitive structuring. The features of the social network enabled enhanced communication between teacher and student, as well as promoted engagement around clinical scenarios. Online social networks can be used to facilitate reflective reasoning as part of the development of practice knowledge by exposing students' understanding of clinical practice. However, careful facilitation using sound pedagogy is still necessary to guide students to deeper understanding.

  1. Integrating online communities and social networks with computerised treatment for insomnia: a qualitative study.

    Science.gov (United States)

    Middlemass, Jo; Davy, Zowie; Cavanagh, Kate; Linehan, Conor; Morgan, Kevin; Lawson, Shaun; Siriwardena, A Niroshan

    2012-12-01

    Insomnia is a common psychological complaint. Cognitive behavioural therapy for insomnia (CBT-I), although effective, is little used because of lack of trained providers. Computerised CBT-I (CCBT-I) may be a solution to this shortfall in access. To explore patient and health professional perspectives and the role of social networking, to develop a novel CCBT-I programme to increase access to this form of intervention. Qualitative methods underpinned by the theory of planned behaviour in primary care in Lincolnshire and Nottinghamshire. Semi-structured interviews and focus groups with a purposive sample of health professionals and adults with insomnia. A total of 23 health professionals and 28 patients were interviewed. Features designed to engender trust and improve functionality were perceived to improve uptake and adherence to CCBT-I. Trust lay in programme accreditation; for professionals, trust derived from evidence of effectiveness; for patients, trust depended on the doctor-patient relationship, professional support, the quality of online peer support, and perceptions of risk. Patients wanted mobile applications; access in short periods; self-assessment; interactive, personalised information on sleep; and moderated contact with other users. Patients and practitioners differed over whether useful information could be distinguished from less useful or potentially incorrect information. Improving uptake and adherence to online programmes for insomnia requires design features focusing on trust and functionality. Enabling greater patient control and interaction with other users and professionals may stimulate positive experiences of online therapy. CCBT-I would enable greater access to treatment but is limited by lack of online access or poor computer literacy.

  2. The rise of the ‘silver surfer’: Online social networking and social inclusion for older adults

    OpenAIRE

    Christina Doyle; Sophie Jennifer Goldingay

    2012-01-01

    As the proportion of older adults continues to grow in many Western countries, there are increasing concerns about how to meet their needs.  Ensuring social connectedness and inclusion is one way to support older adults’ wellbeing.  Online social networking has become common place amongst younger age groups, suggesting its possible usefulness for older adults, in order to combat isolation and loneliness.  Some quantitative studies have already explored the amount and degree of online social n...

  3. Political campaigning 2.0: The influence of online news and social networking sites on attitudes and behavior

    Directory of Open Access Journals (Sweden)

    Montathar Faraon

    2014-11-01

    Full Text Available This study aimed to examine differences in influence between online news (e.g., New York Times and social networking sites (e.g., Facebook and Twitter on attitudes in political campaigns. In a web-based experiment, campaign, polls and election between two fictitious candidates were simulated. Participants’ explicit and implicit attitudes as well as voting behavior were assessed using self-report items and the Implicit Association Test (IAT. The results reveal that information emanating from online news had a significant influence on explicit and implicit attitudes while that of social networking sites did not. Overall, negative items had a stronger impact than positive ones, more so in online news compared to social networking sites. Negative information from either type of media was more likely to change participants’ explicit attitudes in a negative direction and as a consequence also change their vote. Practical implications of the findings and limitations of the study are discussed.

  4. Using Pathfinder networks to discover alignment between expert and consumer conceptual knowledge from online vaccine content.

    Science.gov (United States)

    Amith, Muhammad; Cunningham, Rachel; Savas, Lara S; Boom, Julie; Schvaneveldt, Roger; Tao, Cui; Cohen, Trevor

    2017-10-01

    This study demonstrates the use of distributed vector representations and Pathfinder Network Scaling (PFNETS) to represent online vaccine content created by health experts and by laypeople. By analyzing a target audience's conceptualization of a topic, domain experts can develop targeted interventions to improve the basic health knowledge of consumers. The underlying assumption is that the content created by different groups reflects the mental organization of their knowledge. Applying automated text analysis to this content may elucidate differences between the knowledge structures of laypeople (heath consumers) and professionals (health experts). This paper utilizes vaccine information generated by laypeople and health experts to investigate the utility of this approach. We used an established technique from cognitive psychology, Pathfinder Network Scaling to infer the structure of the associational networks between concepts learned from online content using methods of distributional semantics. In doing so, we extend the original application of PFNETS to infer knowledge structures from individual participants, to infer the prevailing knowledge structures within communities of content authors. The resulting graphs reveal opportunities for public health and vaccination education experts to improve communication and intervention efforts directed towards health consumers. Our efforts demonstrate the feasibility of using an automated procedure to examine the manifestation of conceptual models within large bodies of free text, revealing evidence of conflicting understanding of vaccine concepts among health consumers as compared with health experts. Additionally, this study provides insight into the differences between consumer and expert abstraction of domain knowledge, revealing vaccine-related knowledge gaps that suggest opportunities to improve provider-patient communication. Copyright © 2017 Elsevier Inc. All rights reserved.

  5. Mobilizing homeless youth for HIV prevention: a social network analysis of the acceptability of a face-to-face and online social networking intervention.

    Science.gov (United States)

    Rice, Eric; Tulbert, Eve; Cederbaum, Julie; Barman Adhikari, Anamika; Milburn, Norweeta G

    2012-04-01

    The objective of the study is to use social network analysis to examine the acceptability of a youth-led, hybrid face-to-face and online social networking HIV prevention program for homeless youth.Seven peer leaders (PLs) engaged face-to-face homeless youth (F2F) in the creation of digital media projects (e.g. You Tube videos). PL and F2F recruited online youth (OY) to participate in MySpace and Facebook communities where digital media was disseminated and discussed. The resulting social networks were assessed with respect to size, growth, density, relative centrality of positions and homophily of ties. Seven PL, 53 F2F and 103 OY created two large networks. After the first 50 F2F youth participated, online networks entered a rapid growth phase. OY were among the most central youth in these networks. Younger aged persons and females were disproportionately connected to like youth. The program appears highly acceptable to homeless youth. Social network analysis revealed which PL were the most critical to the program and which types of participants (younger youth and females) may require additional outreach efforts in the future.

  6. The relationship between online social networking and sexual risk behaviors among men who have sex with men (MSM).

    Science.gov (United States)

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

    2013-01-01

    Online social networking usage is growing rapidly, especially among at-risk populations, such as men who have sex with men (MSM). However, little research has studied the relationship between online social networking usage and sexual risk behaviors among at-risk populations. One hundred and eighteen Facebook-registered MSM (60.1% Latino, 28% African American; 11.9% other) were recruited from online (social networking websites and banner advertisements) and offline (local clinics, restaurants and organizations) venues frequented by minority MSM. Inclusion criteria required participants to be men who were 18 years of age or older, had had sex with a man in the past 12 months, were living in Los Angeles, and had a Facebook account. Participants completed an online survey on their social media usage and sexual risk behaviors. Results from a multivariable regression suggest that number of sexual partners met from online social networking technologies is associated with increased: 1) likelihood of having exchanged sex for food, drugs, or a place to stay within the past 3 months; 2) number of new partners within the past 3 months; 3) number of male sex partners within the past 3 months; and 4) frequency of engaging in oral sex within the past 3 months, controlling for age, race, education, and total number of sexual partners. Understanding the relationship between social media sex-seeking and sexual risk behaviors among at-risk populations will help inform population-focused HIV prevention and treatment interventions.

  7. The relationship between online social networking and sexual risk behaviors among men who have sex with men (MSM.

    Directory of Open Access Journals (Sweden)

    Sean D Young

    Full Text Available Online social networking usage is growing rapidly, especially among at-risk populations, such as men who have sex with men (MSM. However, little research has studied the relationship between online social networking usage and sexual risk behaviors among at-risk populations. One hundred and eighteen Facebook-registered MSM (60.1% Latino, 28% African American; 11.9% other were recruited from online (social networking websites and banner advertisements and offline (local clinics, restaurants and organizations venues frequented by minority MSM. Inclusion criteria required participants to be men who were 18 years of age or older, had had sex with a man in the past 12 months, were living in Los Angeles, and had a Facebook account. Participants completed an online survey on their social media usage and sexual risk behaviors. Results from a multivariable regression suggest that number of sexual partners met from online social networking technologies is associated with increased: 1 likelihood of having exchanged sex for food, drugs, or a place to stay within the past 3 months; 2 number of new partners within the past 3 months; 3 number of male sex partners within the past 3 months; and 4 frequency of engaging in oral sex within the past 3 months, controlling for age, race, education, and total number of sexual partners. Understanding the relationship between social media sex-seeking and sexual risk behaviors among at-risk populations will help inform population-focused HIV prevention and treatment interventions.

  8. Improving Stability and Convergence for Adaptive Radial Basis Function Neural Networks Algorithm. (On-Line Harmonics Estimation Application

    Directory of Open Access Journals (Sweden)

    Eyad K Almaita

    2017-03-01

    Keywords: Energy efficiency, Power quality, Radial basis function, neural networks, adaptive, harmonic. Article History: Received Dec 15, 2016; Received in revised form Feb 2nd 2017; Accepted 13rd 2017; Available online How to Cite This Article: Almaita, E.K and Shawawreh J.Al (2017 Improving Stability and Convergence for Adaptive Radial Basis Function Neural Networks Algorithm (On-Line Harmonics Estimation Application.  International Journal of Renewable Energy Develeopment, 6(1, 9-17. http://dx.doi.org/10.14710/ijred.6.1.9-17

  9. To Enhance Collaborative Learning and Practice Network Knowledge with a Virtualization Laboratory and Online Synchronous Discussion

    Directory of Open Access Journals (Sweden)

    Wu-Yuin Hwang

    2014-09-01

    Full Text Available Recently, various computer networking courses have included additional laboratory classes in order to enhance students’ learning achievement. However, these classes need to establish a suitable laboratory where each student can connect network devices to configure and test functions within different network topologies. In this case, the Linux operating system can be used to operate network devices and the virtualization technique can include multiple OSs for supporting a significant number of students. In previous research, the virtualization application was successfully applied in a laboratory, but focused only on individual assignments. The present study extends previous research by designing the Networking Virtualization-Based Laboratory (NVBLab, which requires collaborative learning among the experimental students. The students were divided into an experimental group and a control group for the experiment. The experimental group performed their laboratory assignments using NVBLab, whereas the control group completed them on virtual machines (VMs that were installed on their personal computers. Moreover, students using NVBLab were provided with an online synchronous discussion (OSD feature that enabled them to communicate with others. The laboratory assignments were divided into two parts: Basic Labs and Advanced Labs. The results show that the experimental group significantly outperformed the control group in two Advanced Labs and the post-test after Advanced Labs. Furthermore, the experimental group’s activities were better than those of the control group based on the total average of the command count per laboratory. Finally, the findings of the interviews and questionnaires with the experimental group reveal that NVBLab was helpful during and after laboratory class.

  10. The rise of the ‘silver surfer’: Online social networking and social inclusion for older adults

    Directory of Open Access Journals (Sweden)

    Christina Doyle

    2012-12-01

    Full Text Available As the proportion of older adults continues to grow in many Western countries, there are increasing concerns about how to meet their needs.  Ensuring social connectedness and inclusion is one way to support older adults’ wellbeing.  Online social networking has become common place amongst younger age groups, suggesting its possible usefulness for older adults, in order to combat isolation and loneliness.  Some quantitative studies have already explored the amount and degree of online social networking amongst older adults.  To add further understanding of how older adults experience social inclusion via the internet, the current qualitative study aimed to explore older adults’ subjective experience of online social networking.  Findings demonstrated a number of supports and barriers to social inclusion which reflect barriers to social inclusion of older adults in the non-virtual world.  Recommendations to support social inclusion of isolated older adults via online social networking are suggested.  Keywords: older adults, social networking, social inclusion, internet, social isolation, wellbeing

  11. Structural and dynamical patterns on online social networks: the Spanish May 15th movement as a case study.

    Directory of Open Access Journals (Sweden)

    Javier Borge-Holthoefer

    Full Text Available The number of people using online social networks in their everyday life is continuously growing at a pace never saw before. This new kind of communication has an enormous impact on opinions, cultural trends, information spreading and even in the commercial success of new products. More importantly, social online networks have revealed as a fundamental organizing mechanism in recent country-wide social movements. In this paper, we provide a quantitative analysis of the structural and dynamical patterns emerging from the activity of an online social network around the ongoing May 15th (15M movement in Spain. Our network is made up by users that exchanged tweets in a time period of one month, which includes the birth and stabilization of the 15M movement. We characterize in depth the growth of such dynamical network and find that it is scale-free with communities at the mesoscale. We also find that its dynamics exhibits typical features of critical systems such as robustness and power-law distributions for several quantities. Remarkably, we report that the patterns characterizing the spreading dynamics are asymmetric, giving rise to a clear distinction between information sources and sinks. Our study represents a first step towards the use of data from online social media to comprehend modern societal dynamics.

  12. Structural and dynamical patterns on online social networks: the Spanish May 15th movement as a case study.

    Science.gov (United States)

    Borge-Holthoefer, Javier; Rivero, Alejandro; García, Iñigo; Cauhé, Elisa; Ferrer, Alfredo; Ferrer, Darío; Francos, David; Iñiguez, David; Pérez, María Pilar; Ruiz, Gonzalo; Sanz, Francisco; Serrano, Fermín; Viñas, Cristina; Tarancón, Alfonso; Moreno, Yamir

    2011-01-01

    The number of people using online social networks in their everyday life is continuously growing at a pace never saw before. This new kind of communication has an enormous impact on opinions, cultural trends, information spreading and even in the commercial success of new products. More importantly, social online networks have revealed as a fundamental organizing mechanism in recent country-wide social movements. In this paper, we provide a quantitative analysis of the structural and dynamical patterns emerging from the activity of an online social network around the ongoing May 15th (15M) movement in Spain. Our network is made up by users that exchanged tweets in a time period of one month, which includes the birth and stabilization of the 15M movement. We characterize in depth the growth of such dynamical network and find that it is scale-free with communities at the mesoscale. We also find that its dynamics exhibits typical features of critical systems such as robustness and power-law distributions for several quantities. Remarkably, we report that the patterns characterizing the spreading dynamics are asymmetric, giving rise to a clear distinction between information sources and sinks. Our study represents a first step towards the use of data from online social media to comprehend modern societal dynamics.

  13. Online network organization of Barcelona en Comú, an emergent movement-party.

    Science.gov (United States)

    Aragón, Pablo; Gallego, Helena; Laniado, David; Volkovich, Yana; Kaltenbrunner, Andreas

    2017-01-01

    The emerging grassroots party Barcelona en Comú won the 2015 Barcelona City Council election. This candidacy was devised by activists involved in the Spanish 15M movement to transform citizen outrage into political change. On the one hand, the 15M movement was based on a decentralized structure. On the other hand, political science literature postulates that parties develop oligarchical leadership structures. This tension motivates to examine whether Barcelona en Comú preserved a decentralized structure or adopted a conventional centralized organization. In this study we develop a computational methodology to characterize the online network organization of every party in the election campaign on Twitter. Results on the network of retweets reveal that, while traditional parties are organized in a single cluster, for Barcelona en Comú two well-defined groups co-exist: a centralized cluster led by the candidate and party accounts, and a decentralized cluster with the movement activists. Furthermore, results on the network of replies also shows a dual structure: a cluster around the candidate receiving the largest attention from other parties, and another with the movement activists exhibiting a higher predisposition to dialogue with other parties.

  14. Subtle role of latency for information diffusion in online social networks

    International Nuclear Information System (INIS)

    Xiong Fei; Wang Xi-Meng; Cheng Jun-Jun

    2016-01-01

    Information diffusion in online social networks is induced by the event of forwarding information for users, and latency exists widely in user spreading behaviors. Little work has been done to reveal the effect of latency on the diffusion process. In this paper, we propose a propagation model in which nodes may suspend their spreading actions for a waiting period of stochastic length. These latent nodes may recover their activity again. Meanwhile, the mechanism of forwarding information is also introduced into the diffusion model. Mean-field analysis and numerical simulations indicate that our model has three nontrivial results. First, the spreading threshold does not correlate with latency in neither homogeneous nor heterogeneous networks, but depends on the spreading and refractory parameter. Furthermore, latency affects the diffusion process and changes the infection scale. A large or small latency parameter leads to a larger final diffusion extent, but the intrinsic dynamics is different. Large latency implies forwarding information rapidly, while small latency prevents nodes from dropping out of interactions. In addition, the betweenness is a better descriptor to identify influential nodes in the model with latency, compared with the coreness and degree. These results are helpful in understanding some collective phenomena of the diffusion process and taking measures to restrain a rumor in social networks. (paper)

  15. Optimal Channel Selection Based on Online Decision and Offline Learning in Multichannel Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Mu Qiao

    2017-01-01

    Full Text Available We propose a channel selection strategy with hybrid architecture, which combines the centralized method and the distributed method to alleviate the overhead of access point and at the same time provide more flexibility in network deployment. By this architecture, we make use of game theory and reinforcement learning to fulfill the optimal channel selection under different communication scenarios. Particularly, when the network can satisfy the requirements of energy and computational costs, the online decision algorithm based on noncooperative game can help each individual sensor node immediately select the optimal channel. Alternatively, when the network cannot satisfy the requirements of energy and computational costs, the offline learning algorithm based on reinforcement learning can help each individual sensor node to learn from its experience and iteratively adjust its behavior toward the expected target. Extensive simulation results validate the effectiveness of our proposal and also prove that higher system throughput can be achieved by our channel selection strategy over the conventional off-policy channel selection approaches.

  16. A neural network device for on-line particle identification in cosmic ray experiments

    International Nuclear Information System (INIS)

    Scrimaglio, R.; Finetti, N.; D'Altorio, L.; Rantucci, E.; Raso, M.; Segreto, E.; Tassoni, A.; Cardarilli, G.C.

    2004-01-01

    On-line particle identification is one of the main goals of many experiments in space both for rare event studies and for optimizing measurements along the orbital trajectory. Neural networks can be a useful tool for signal processing and real time data analysis in such experiments. In this document we report on the performances of a programmable neural device which was developed in VLSI analog/digital technology. Neurons and synapses were accomplished by making use of Operational Transconductance Amplifier (OTA) structures. In this paper we report on the results of measurements performed in order to verify the agreement of the characteristic curves of each elementary cell with simulations and on the device performances obtained by implementing simple neural structures on the VLSI chip. A feed-forward neural network (Multi-Layer Perceptron, MLP) was implemented on the VLSI chip and trained to identify particles by processing the signals of two-dimensional position-sensitive Si detectors. The radiation monitoring device consisted of three double-sided silicon strip detectors. From the analysis of a set of simulated data it was found that the MLP implemented on the neural device gave results comparable with those obtained with the standard method of analysis confirming that the implemented neural network could be employed for real time particle identification

  17. Actual versus perceived peer sexual risk behavior in online youth social networks.

    Science.gov (United States)

    Black, Sandra R; Schmiege, Sarah; Bull, Sheana

    2013-09-01

    Perception of peer behaviors is an important predictor of actual risk behaviors among youth. However, we lack understanding of peer influence through social media and of actual and perceived peer behavior concordance. The purpose of this research is to document the relationship between individual perception of and actual peer sexual risk behavior using online social networks. The data are a result of a secondary analysis of baseline self-reported and peer-reported sexual risk behavior from a cluster randomized trial including 1,029 persons from 162 virtual networks. Individuals (seeds) recruited up to three friends who then recruited additional friends, extending three waves from the seed. ANOVA models compared network means of actual participant behavior across categories of perceived behavior. Concordance varied between reported and perceived behavior, with higher concordance between perceived and reported condom use, multiple partners, concurrent partners, sexual pressure, and drug and alcohol use during sex. Individuals significantly over-reported risk and under-reported protective peer behaviors related to sex.

  18. Online identity: constructing interpersonal trust and openness through participating in hospitality social networks

    Directory of Open Access Journals (Sweden)

    Alexander Ronzhyn

    2013-06-01

    Full Text Available The present article describes the results of research on online identity construction during the participation in the hospitality social networks. Specifically the user references are analysed to understand patterns that form the image of a member. CouchSurfing service (couchsurfing.org allows users to leave short texts where the experience of hosting/being hosted by a CS member is described, is an evaluation of the CS members of each other’s personal traits, skills and common experience. Therefore references can become a good instrument for portraying a CouchSurfing member and understanding his or her particular traits. References form an important part of a user’s virtual identity in the network. Using a sample of references of Spanish CouchSurfing users, the research established main characteristics of the references, which are the openness, readiness to share ideas and experiences and trustworthiness. These concepts illustrate the typical traits associated with a user of the network and also shed light on the activities common during offl ine CS meetings

  19. Online Learning Algorithm for Time Series Forecasting Suitable for Low Cost Wireless Sensor Networks Nodes

    Directory of Open Access Journals (Sweden)

    Juan Pardo

    2015-04-01

    Full Text Available Time series forecasting is an important predictive methodology which can be applied to a wide range of problems. Particularly, forecasting the indoor temperature permits an improved utilization of the HVAC (Heating, Ventilating and Air Conditioning systems in a home and thus a better energy efficiency. With such purpose the paper describes how to implement an Artificial Neural Network (ANN algorithm in a low cost system-on-chip to develop an autonomous intelligent wireless sensor network. The present paper uses a Wireless Sensor Networks (WSN to monitor and forecast the indoor temperature in a smart home, based on low resources and cost microcontroller technology as the 8051MCU. An on-line learning approach, based on Back-Propagation (BP algorithm for ANNs, has been developed for real-time time series learning. It performs the model training with every new data that arrive to the system, without saving enormous quantities of data to create a historical database as usual, i.e., without previous knowledge. Consequently to validate the approach a simulation study through a Bayesian baseline model have been tested in order to compare with a database of a real application aiming to see the performance and accuracy. The core of the paper is a new algorithm, based on the BP one, which has been described in detail, and the challenge was how to implement a computational demanding algorithm in a simple architecture with very few hardware resources.

  20. Learning from Your Network of Friends: A Trajectory Representation Learning Model Based on Online Social Ties

    KAUST Repository

    Alharbi, Basma Mohammed

    2017-02-07

    Location-Based Social Networks (LBSNs) capture individuals whereabouts for a large portion of the population. To utilize this data for user (location)-similarity based tasks, one must map the raw data into a low-dimensional uniform feature space. However, due to the nature of LBSNs, many users have sparse and incomplete check-ins. In this work, we propose to overcome this issue by leveraging the network of friends, when learning the new feature space. We first analyze the impact of friends on individuals\\'s mobility, and show that individuals trajectories are correlated with thoseof their friends and friends of friends (2-hop friends) in an online setting. Based on our observation, we propose a mixed-membership model that infers global mobility patterns from users\\' check-ins and their network of friends, without impairing the model\\'s complexity. Our proposed model infers global patterns and learns new representations for both usersand locations simultaneously. We evaluate the inferred patterns and compare the quality of the new user representation against baseline methods on a social link prediction problem.

  1. Mobilizing Homeless Youth for HIV Prevention: A Social Network Analysis of the Acceptability of a Face-to-Face and Online Social Networking Intervention

    Science.gov (United States)

    Rice, Eric; Tulbert, Eve; Cederbaum, Julie; Adhikari, Anamika Barman; Milburn, Norweeta G.

    2012-01-01

    The objective of the study is to use social network analysis to examine the acceptability of a youth-led, hybrid face-to-face and online social networking HIV prevention program for homeless youth. Seven peer leaders (PLs) engaged face-to-face homeless youth (F2F) in the creation of digital media projects (e.g. You Tube videos). PL and F2F…

  2. Social Networks Used by Teens and Parental Control of Their Online Communication

    Directory of Open Access Journals (Sweden)

    M. Shehu

    2017-06-01

    Full Text Available The Internet plays important functions in identity formation, personal autono-my, and relationships outside the family. It allows teens to develop their own interests, to identify with others. The aim of the study is to present concrete evidence regarding to the communication through social networks and parental care in the management of online communication. Referring questionnaire “Student Needs Assessment Survey” by N. E. Willard (2007, but the author has selected questions to the scope of its study. The sample of the study includes 255 pupils aged 15 – 19 (110 Male and 145 Female. The statistical data processing was performed by SPPS statistical program, version 20. Cronbach’s Alpha 0.764 were used to assess the reliability of the instrument. The most favorite activity on the Internet by the teens is navigation on the In-ternet to see/learn new things (68.6%, during the week the subjects spend ap-proximately less than 2 hours per day (34.1% of them. Most of teenagers (82.7% claims to have communication with their parents about how they treats their friends and 56.5% of them say that sometimes have control by their par-ents for what they do online. If pupils would victim of pressure on the internet and do not have opportunities to can be contained by those 69% of them approve that they would tell to their parents and also (63.9% to school staff members. When there have been cases of violence, even threatening suicide rate of reporting and collaboration between parent - teacher is high, while in other elements resulting lower interest rates. One of the main factors in man-agement of this online communication and Internet is the parent care, which is considered most important in terms of education and not only.

  3. A conceptual model for analysing informal learning in online social networks for health professionals.

    Science.gov (United States)

    Li, Xin; Gray, Kathleen; Chang, Shanton; Elliott, Kristine; Barnett, Stephen

    2014-01-01

    Online social networking (OSN) provides a new way for health professionals to communicate, collaborate and share ideas with each other for informal learning on a massive scale. It has important implications for ongoing efforts to support Continuing Professional Development (CPD) in the health professions. However, the challenge of analysing the data generated in OSNs makes it difficult to understand whether and how they are useful for CPD. This paper presents a conceptual model for using mixed methods to study data from OSNs to examine the efficacy of OSN in supporting informal learning of health professionals. It is expected that using this model with the dataset generated in OSNs for informal learning will produce new and important insights into how well this innovation in CPD is serving professionals and the healthcare system.

  4. SMEs Going Global: A Comparison of the Internationalization Strategies of Publishers and Online Social Networks

    Directory of Open Access Journals (Sweden)

    Bettina Lis

    2012-01-01

    Full Text Available Up to now, most research has been conducted on the internationalization strategies of large media companies and groups. But tapping new foreign markets is also relevant to small- and medium-sized enterprises (SMEs of all media sectors. This paper therefore focuses on the internationalization strategies of different types of media SMEs. It aims at describing and comparing the motives for becoming an international player as well as the specific market selection, market entry, and market development strategies. Furthermore, it focuses on the main organizational implications. On the basis of a multiple-case design we compare two German regional newspaper publishers with two German special interest publishers and two online social business networks. Results show similarities and differences between these media sectors according to the nature of the media businesses. The cases also highlight the importance of international management skills also in the context of SMEs.

  5. Does Posting Facebook Status Updates Increase or Decrease Loneliness? An Online Social Networking Experiment.

    Science.gov (United States)

    Deters, Fenne Große; Mehl, Matthias R

    2013-09-01

    Online social networking is a pervasive but empirically understudied phenomenon. Strong public opinions on its consequences exist but are backed up by little empirical evidence and almost no causally-conclusive, experimental research. The current study tested the psychological effects of posting status updates on Facebook using an experimental design. For one week, participants in the experimental condition were asked to post more than they usually do, whereas participants in the control condition received no instructions. Participants added a lab "Research Profile" as a Facebook friend allowing for the objective documentation of protocol compliance, participants' status updates, and friends' responses. Results revealed (1) that the experimentally-induced increase in status updating activity reduced loneliness, (2) that the decrease in loneliness was due to participants feeling more connected to their friends on a daily basis and (3) that the effect of posting on loneliness was independent of direct social feedback (i.e. responses) by friends.

  6. African American Social Networking Online: Applying a Digital Practice Approach to Understanding Digital Inequalities

    Directory of Open Access Journals (Sweden)

    Danielle Taana Smith

    2013-06-01

    Full Text Available This study develops a framework for systematic examination of information and communication technologies (ICTs usage differences within a group. This framework situates the digital divide and digital inequalities model within a broader conceptual model of digital practice, exemplified by how groups of people use ICTs. I use nationally representative data to examine online activities on social networking sites (SNS for African Americans and other ethnoracial groups. The data for this research comes from the Pew Internet and American Life’s “Spring Tracking Survey 2008”. The results from regression analyses support the digital practice framework which moves discussions of ICT usage beyond social and economic advantages or disadvantages, and addresses individual and group needs in using these technologies.

  7. Effect of users' opinion evolution on information diffusion in online social networks

    Science.gov (United States)

    Zhu, Hengmin; Kong, Yuehan; Wei, Jing; Ma, Jing

    2018-02-01

    The process of topic propagation always interweaves information diffusion and opinion evolution, but most previous works studied the models of information diffusion and opinion evolution separately, and seldom focused on their interaction of each other. To shed light on the effect of users' opinion evolution on information diffusion in online social networks, we proposed a model which incorporates opinion evolution into the process of topic propagation. Several real topics propagating on Sina Microblog were collected to analyze individuals' propagation intentions, and different propagation intentions were considered in the model. The topic propagation was simulated to explore the impact of different opinion distributions and intervention with opposite opinion on information diffusion. Results show that the topic with one-sided opinions can spread faster and more widely, and intervention with opposite opinion is an effective measure to guide the topic propagation. The earlier to intervene, the more effectively the topic propagation would be guided.

  8. Online state-of-health estimation of lithium-ion batteries using Dynamic Bayesian Networks

    Science.gov (United States)

    He, Zhiwei; Gao, Mingyu; Ma, Guojin; Liu, Yuanyuan; Chen, Sanxin

    2014-12-01

    Li-ion batteries are widely used in energy storage systems, electric vehicles, communication systems, etc. The State of Health (SOH) of batteries is of great importance to the safety of these systems. This paper presents a novel online method for the estimation of the SOH of Lithium (Li)-ion batteries based on Dynamic Bayesian Networks (DBNs). The structure of the DBN model is built according to the experience of experts, with the state of charges used as hidden states and the terminal voltages used as observations in the DBN. Parameters of the DBN model are learned based on training data collected through Li-ion battery aging experiments. A forward algorithm is applied for the inference of the DBN model in order to estimate the SOH in real-time. Experimental results show that the proposed method is effective and efficient in estimating the SOH of Li-ion batteries.

  9. Structure and stability of online chat networks built on emotion-carrying links

    Science.gov (United States)

    Gligorijević, Vladimir; Skowron, Marcin; Tadić, Bosiljka

    2013-02-01

    High-resolution data of online chats are studied as a physical system in the laboratory in order to quantify collective behavior of users. Our analysis reveals strong regularities characteristic of natural systems with additional features. In particular, we find self-organized dynamics with long-range correlations in user actions and persistent associations among users that have the properties of a social network. Furthermore, the evolution of the graph and its architecture with specific k-core structure are shown to be related with the type and the emotion arousal of exchanged messages. Partitioning of the graph by deletion of the links which carry high arousal messages exhibits critical fluctuations at the percolation threshold.

  10. The adoption and spread of a core-strengthening exercise through an online social network.

    Science.gov (United States)

    Pagoto, Sherry L; Schneider, Kristin L; Oleski, Jessica; Smith, Brian; Bauman, Michael

    2014-03-01

    The present feasibility study describes engagement and spread of a Twitter-based core-strengthening challenge. A challenge that entailed completing a core-strengthening exercise using a hashtag (#PlankADay) was circulated via Twitter. This study surveyed users who joined during the first 2 months of the challenge to describe their characteristics, including social support for exercise and to what extent they invited others to join. The study continued to track total users for 10 months. Of 407 individuals who joined in the first 2 months, 105 completed surveys. Among these, 81% were female and 86% white and mean age was 35.8. 72% participated for at least 1 month and 47% participated for at least 2 months. Survey participants reported that the challenge increased their enjoyment of abdominal exercise. Of the 68% of participants who invited others to participate, 28% recruited none, 66% recruited 1-5 users, and 6% recruited 10 or more users. Participants reported that online friends provided as much positive social support for exercise as family and in-person friends. In 14 months, 4941 users produced 76,746 tweets and mean total tweets per user was 15.86 (SD = 75.34; range = 1-2888). Online social networks may be a promising mechanism to spread brief exercise behaviors.

  11. Engagement, compliance and retention with a gamified online social networking physical activity intervention.

    Science.gov (United States)

    Ryan, Jillian; Edney, Sarah; Maher, Carol

    2017-12-01

    Health behaviour interventions delivered via online social networks are an increasingly popular approach to addressing lifestyle-related health problems. However, research to date consistently reports poor user engagement and retention. The current study examined user engagement, compliance and retention with Active Team-a gamified physical activity intervention delivered by via an online Facebook application. Associations between engagement and participant (n = 51) demographic and team characteristics (sex, age, education and team size) were examined, as well as temporal trends in engagement during the 50-day intervention. Analyses revealed significant associations between both engagement (p = engagement and use of gamification features. Gender was also related to engagement, with males demonstrating the highest use of the intervention's gamification features (p = 0.004). Although compliance was consistently high for the duration, engagement declined steadily throughout the intervention. Engagement peaked on Wednesdays, coinciding with the delivery of a customised email reminder. Findings reveal individual differences in engagement with Active Team, highlighting a need to tailor interventions to the target audience. Gamification features may enhance engagement amongst males, who are traditionally recognised as a difficult demographic group to engage. Finally, the use of customised, periodic push reminders delivered by email may enhance user engagement by drawing them back to the intervention and helping to sustain intervention behaviours.

  12. Energy Efficient Power Allocation in Multi-tier 5G Networks Using Enhanced Online Learning

    KAUST Repository

    Alqerm, Ismail

    2017-07-25

    The multi-tier heterogeneous structure of 5G with dense small cells deployment, relays, and device-to-device (D2D) communications operating in an underlay fashion is envisioned as a potential solution to satisfy the future demand for cellular services. However, efficient power allocation among dense secondary transmitters that maintains quality of service (QoS) for macro (primary) cell users and secondary cell users is a critical challenge for operating such radio. In this paper, we focus on the power allocation problem in the multi-tier 5G network structure using a non-cooperative methodology with energy efficiency consideration. Therefore, we propose a distributive intuition-based online learning scheme for power allocation in the downlink of the 5G systems, where each transmitter surmises other transmitters power allocation strategies without information exchange. The proposed learning model exploits a brief state representation to account for the problem of dimensionality in online learning and expedite the convergence. The convergence of the proposed scheme is proved and numerical results demonstrate its capability to achieve fast convergence with QoS guarantee and significant improvement in system energy efficiency.

  13. How risky are social networking sites? A comparison of places online where youth sexual solicitation and harassment occurs.

    Science.gov (United States)

    Ybarra, Michele L; Mitchell, Kimberly J

    2008-02-01

    Recently, public attention has focused on the possibility that social networking sites such as MySpace and Facebook are being widely used to sexually solicit underage youth, consequently increasing their vulnerability to sexual victimization. Beyond anecdotal accounts, however, whether victimization is more commonly reported in social networking sites is unknown. The Growing up With Media Survey is a national cross-sectional online survey of 1588 youth. Participants were 10- to 15-year-old youth who have used the Internet at least once in the last 6 months. The main outcome measures were unwanted sexual solicitation on the Internet, defined as unwanted requests to talk about sex, provide personal sexual information, and do something sexual, and Internet harassment, defined as rude or mean comments, or spreading of rumors. Fifteen percent of all of the youth reported an unwanted sexual solicitation online in the last year; 4% reported an incident on a social networking site specifically. Thirty-three percent reported an online harassment in the last year; 9% reported an incident on a social networking site specifically. Among targeted youth, solicitations were more commonly reported via instant messaging (43%) and in chat rooms (32%), and harassment was more commonly reported in instant messaging (55%) than through social networking sites (27% and 28%, respectively). Broad claims of victimization risk, at least defined as unwanted sexual solicitation or harassment, associated with social networking sites do not seem justified. Prevention efforts may have a greater impact if they focus on the psychosocial problems of youth instead of a specific Internet application, including funding for online youth outreach programs, school antibullying programs, and online mental health services.

  14. ONLINE SOCIAL NETWORKS AS A TOOL FOR THE PROMOTION OF PHYSICAL ACTIVITY AND HEALTH: A RESOURCE SCIENTIFICALLY FEW EXPLORED

    Directory of Open Access Journals (Sweden)

    Arían Ramón Aladro Gonzalvo

    2015-06-01

    Full Text Available Due to the great impact  that are exerting the networks in society, it is crucial to know the features that distinguish online social networks bringing together users interested in receiving information and resources to improve or maintain the body in shape. This article aims to comment on the limited research interested in studying the features and particularities of online communities that provide information, advice and support in the execution, performance and promotion of the health and fitness activities. Particularly, it underline about the necessity to know of networks structure, user profiles and peer-to-peer interaction, sort of membership, mechanisms of communication, representation of the body image and patterns of association. Likewise, the size of the support networks, telepresence, technology acceptance and perceived risk on the network. Besides, we recommend exploring two Fitness-related online social networks. Finally, it makes known the recurring problems in the analysis in order to characterize psychosocial and communicative aspects of users in the virtual environment.

  15. Online social networking in adolescence: patterns of use in six European countries and links with psychosocial functioning.

    NARCIS (Netherlands)

    Tsitsika, A.K.; Tzavela, E.C.; Janikian, M.; Olafsson, K.; Iordache, A.; Schoenmakers, T.M.; Tzavara, C.; Richardson, C.

    2014-01-01

    Purpose: Online communication tools, such as social networking sites (SNS), have been comprehensively embraced by adolescents and have become a dominant daily social practice. Recognizing SNS as a key context of adolescent development, this study aimed to investigate associations between heavier SNS

  16. Development and Analyses of Privacy Management Models in Online Social Networks Based on Communication Privacy Management Theory

    Science.gov (United States)

    Lee, Ki Jung

    2013-01-01

    Online social networks (OSNs), while serving as an emerging means of communication, promote various issues of privacy. Users of OSNs encounter diverse occasions that lead to invasion of their privacy, e.g., published conversation, public revelation of their personally identifiable information, and open boundary of distinct social groups within…

  17. Conversational Scholarship in Cyberspace: The Evolution and Activities of H-Net, the Online Network for the Humanities.

    Science.gov (United States)

    Turnbull, Paul

    1996-01-01

    The origins and current use of H-Net, an online humanities network on the World Wide Web, are examined. H-Net currently sponsors 73 electronic discussion lists that reach subscribers in 68 countries. Discussion groups have not met expectations for scholarly exchange, possibly because of plagiarism and copyright concerns. New ventures include book…

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

    NARCIS (Netherlands)

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

    2013-01-01

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

  19. Online teaching of inflammatory skin pathology by a French-speaking International University Network

    Science.gov (United States)

    2014-01-01

    Introduction Developments in technology, web-based teaching and whole slide imaging have broadened the teaching horizon in anatomic pathology. Creating online learning material including many types of media such as radiologic images, whole slides, videos, clinical and macroscopic photographs, is now accessible to most universities. Unfortunately, a major limiting factor to maintain and update the learning material is the amount of resources needed. In this perspective, a French-national university network was initiated in 2011 to build joint online teaching modules consisting of clinical cases and tests. The network has since expanded internationally to Québec, Switzerland and Ivory Coast. Method One of the first steps of the project was to build a learning module on inflammatory skin pathology for interns and residents in pathology and dermatology. A pathology resident from Québec spent 6 weeks in France and Switzerland to develop the contents and build the module on an e-learning Moodle platform under the supervision of two dermatopathologists. The learning module contains text, interactive clinical cases, tests with feedback, virtual slides, images and clinical photographs. For that module, the virtual slides are decentralized in 2 universities (Bordeaux and Paris 7). Each university is responsible of its own slide scanning, image storage and online display with virtual slide viewers. Results The module on inflammatory skin pathology includes more than 50 web pages with French original content, tests and clinical cases, links to over 45 virtual images and more than 50 microscopic and clinical photographs. The whole learning module is being revised by four dermatopathologists and two senior pathologists. It will be accessible to interns and residents in the spring of 2014. The experience and knowledge gained from that work will be transferred to the next international resident whose work will be aimed at creating lung and breast pathology learning modules

  20. Online social network use by health care providers in a high traffic patient care environment.

    Science.gov (United States)

    Black, Erik; Light, Jennifer; Paradise Black, Nicole; Thompson, Lindsay

    2013-05-17

    The majority of workers, regardless of age or occupational status, report engaging in personal Internet use in the workplace. There is little understanding of the impact that personal Internet use may have on patient care in acute clinical settings. The objective of this study was to investigate the volume of one form of personal Internet use-online social networking (Facebook)-generated by workstations in the emergency department (ED) in contrast to measures of clinical volume and severity. The research team analyzed anonymous network utilization records for 68 workstations located in the emergency medicine department within one academic medical center for 15 consecutive days (12/29/2009 to 1/12/2010). This data was compared to ED work index (EDWIN) data derived by the hospital information systems. Health care workers spent an accumulated 4349 minutes (72.5 hours) browsing Facebook, staff cumulatively visited Facebook 9369 times and spent, on average, 12.0 minutes per hour browsing Facebook. There was a statistically significant difference in the time spent on Facebook according to time of day (19.8 minutes per hour versus 4.3 minutes per hour, P<.001). There was a significant, positive correlation between EDWIN scores and time spent on Facebook (r=.266, P<.001). Facebook use constituted a substantive percentage of staff time during the 15-day observation period. Facebook use increased with increased patient volume and severity within the ED.

  1. Online social networking addiction among college students in Singapore: Comorbidity with behavioral addiction and affective disorder.

    Science.gov (United States)

    Tang, Catherine So-Kum; Koh, Yvaine Yee Woen

    2017-02-01

    This study aimed to determine the prevalence of addiction to social networking sites/platforms (SNS) and its comorbidity with other behavioral addiction and affective disorder among college students in Singapore. 1110 college students (age: M=21.46, SD=1.80) in Singapore completed measures assessing online social networking, unhealthy food intake and shopping addiction as well as depression, anxiety and mania. Descriptive analyses were conducted to investigate the prevalence and comorbidity of behavioral addiction and affective disorder. Chi-square tests were used to examine gender differences. The prevalence rates of SNS, food and shopping addiction were 29.5%, 4.7% and 9.3% respectively for the total sample. SNS addiction was found to co-occur with food addiction (3%), shopping addiction (5%), and both food and shopping addiction (1%). The comorbidity rates of SNS addiction and affective disorder were 21% for depression, 27.7% for anxiety, and 26.1% for mania. Compared with the total sample, students with SNS addiction reported higher comorbidity rates with other behavioral addiction and affective disorder. In general, females as compared to males reported higher comorbidity rates of SNS addiction and affective disorder. SNS addiction has a high prevalence rate among college students in Singapore. Students with SNS addiction were vulnerable to experience other behavior addiction as well as affective disorder, especially among females. Copyright © 2016. Published by Elsevier B.V.

  2. Applying social network analysis to understand the knowledge sharing behaviour of practitioners in a clinical online discussion forum.

    Science.gov (United States)

    Stewart, Samuel Alan; Abidi, Syed Sibte Raza

    2012-12-04

    Knowledge Translation (KT) plays a vital role in the modern health care community, facilitating the incorporation of new evidence into practice. Web 2.0 tools provide a useful mechanism for establishing an online KT environment in which health practitioners share their practice-related knowledge and experiences with an online community of practice. We have implemented a Web 2.0 based KT environment--an online discussion forum--for pediatric pain practitioners across seven different hospitals in Thailand. The online discussion forum enabled the pediatric pain practitioners to share and translate their experiential knowledge to help improve the management of pediatric pain in hospitals. The goal of this research is to investigate the knowledge sharing dynamics of a community of practice through an online discussion forum. We evaluated the communication patterns of the community members using statistical and social network analysis methods in order to better understand how the online community engages to share experiential knowledge. Statistical analyses and visualizations provide a broad overview of the communication patterns within the discussion forum. Social network analysis provides the tools to delve deeper into the social network, identifying the most active members of the community, reporting the overall health of the social network, isolating the potential core members of the social network, and exploring the inter-group relationships that exist across institutions and professions. The statistical analyses revealed a network dominated by a single institution and a single profession, and found a varied relationship between reading and posting content to the discussion forum. The social network analysis discovered a healthy network with strong communication patterns, while identifying which users are at the center of the community in terms of facilitating communication. The group-level analysis suggests that there is strong interprofessional and interregional

  3. Dynamic evolving spiking neural networks for on-line spatio- and spectro-temporal pattern recognition.

    Science.gov (United States)

    Kasabov, Nikola; Dhoble, Kshitij; Nuntalid, Nuttapod; Indiveri, Giacomo

    2013-05-01

    On-line learning and recognition of spatio- and spectro-temporal data (SSTD) is a very challenging task and an important one for the future development of autonomous machine learning systems with broad applications. Models based on spiking neural networks (SNN) have already proved their potential in capturing spatial and temporal data. One class of them, the evolving SNN (eSNN), uses a one-pass rank-order learning mechanism and a strategy to evolve a new spiking neuron and new connections to learn new patterns from incoming data. So far these networks have been mainly used for fast image and speech frame-based recognition. Alternative spike-time learning methods, such as Spike-Timing Dependent Plasticity (STDP) and its variant Spike Driven Synaptic Plasticity (SDSP), can also be used to learn spatio-temporal representations, but they usually require many iterations in an unsupervised or semi-supervised mode of learning. This paper introduces a new class of eSNN, dynamic eSNN, that utilise both rank-order learning and dynamic synapses to learn SSTD in a fast, on-line mode. The paper also introduces a new model called deSNN, that utilises rank-order learning and SDSP spike-time learning in unsupervised, supervised, or semi-supervised modes. The SDSP learning is used to evolve dynamically the network changing connection weights that capture spatio-temporal spike data clusters both during training and during recall. The new deSNN model is first illustrated on simple examples and then applied on two case study applications: (1) moving object recognition using address-event representation (AER) with data collected using a silicon retina device; (2) EEG SSTD recognition for brain-computer interfaces. The deSNN models resulted in a superior performance in terms of accuracy and speed when compared with other SNN models that use either rank-order or STDP learning. The reason is that the deSNN makes use of both the information contained in the order of the first input spikes

  4. Sophisticated Online Learning Scheme for Green Resource Allocation in 5G Heterogeneous Cloud Radio Access Networks

    KAUST Repository

    Alqerm, Ismail

    2018-01-23

    5G is the upcoming evolution for the current cellular networks that aims at satisfying the future demand for data services. Heterogeneous cloud radio access networks (H-CRANs) are envisioned as a new trend of 5G that exploits the advantages of heterogeneous and cloud radio access networks to enhance spectral and energy efficiency. Remote radio heads (RRHs) are small cells utilized to provide high data rates for users with high quality of service (QoS) requirements, while high power macro base station (BS) is deployed for coverage maintenance and low QoS users service. Inter-tier interference between macro BSs and RRHs and energy efficiency are critical challenges that accompany resource allocation in H-CRANs. Therefore, we propose an efficient resource allocation scheme using online learning, which mitigates interference and maximizes energy efficiency while maintaining QoS requirements for all users. The resource allocation includes resource blocks (RBs) and power. The proposed scheme is implemented using two approaches: centralized, where the resource allocation is processed at a controller integrated with the baseband processing unit and decentralized, where macro BSs cooperate to achieve optimal resource allocation strategy. To foster the performance of such sophisticated scheme with a model free learning, we consider users\\' priority in RB allocation and compact state representation learning methodology to improve the speed of convergence and account for the curse of dimensionality during the learning process. The proposed scheme including both approaches is implemented using software defined radios testbed. The obtained results and simulation results confirm that the proposed resource allocation solution in H-CRANs increases the energy efficiency significantly and maintains users\\' QoS.

  5. Privacy Practices of Health Social Networking Sites: Implications for Privacy and Data Security in Online Cancer Communities.

    Science.gov (United States)

    Charbonneau, Deborah H

    2016-08-01

    While online communities for social support continue to grow, little is known about the state of privacy practices of health social networking sites. This article reports on a structured content analysis of privacy policies and disclosure practices for 25 online ovarian cancer communities. All of the health social networking sites in the study sample provided privacy statements to users, yet privacy practices varied considerably across the sites. The majority of sites informed users that personal information was collected about participants and shared with third parties (96%, n = 24). Furthermore, more than half of the sites (56%, n = 14) stated that cookies technology was used to track user behaviors. Despite these disclosures, only 36% (n = 9) offered opt-out choices for sharing data with third parties. In addition, very few of the sites (28%, n = 7) allowed individuals to delete their personal information. Discussions about specific security measures used to protect personal information were largely missing. Implications for privacy, confidentiality, consumer choice, and data safety in online environments are discussed. Overall, nurses and other health professionals can utilize these findings to encourage individuals seeking online support and participating in social networking sites to build awareness of privacy risks to better protect their personal health information in the digital age.

  6. Online Social Network Users’ Attitudes toward Personality Traits Predict Behaviour of their Friends

    Directory of Open Access Journals (Sweden)

    Sergei A. Shchebetenko

    2016-12-01

    Full Text Available The research considers attitudes toward personality traits in online social network (OSN Vkontakte users’ behaviour. Users’ friends’ activity on a given user’s profile was supposed to be affected by attitudes toward traits of the latter. Within a broader context, the role of metacognitive type of characteristic adaptations as a key element of the five-factor theory of personality is studied. Accordingly, along with attitudes toward traits, other metacognitive characteristic adaptations are examined (e.g. dispositional efficiency, reflected trait, and reflected attitude toward a trait. 1030 undergraduates participated in the study. The research results confirm that extraversion is the most important predictor of OSN behavior among other personality traits. The information presented in this research is obtained using behavioural data instead of more convenient self-reports. Moreover, these behavioural data characterise other users’ (friends’ behaviour while addressing a certain user’s profile. Positive attitudes toward each Big Five traits (extraversion, agreeableness, conscientiousness, emotional stability, and openness to experience separately affected the number of “Likes” of the avatars representing users’ photographs. Furthermore, revealed correlations between traits and “Likes” were subsequently eliminated by the attitudes toward respective traits. Positive attitudes toward conscientiousness predicted the increase of friends’ number unlike trait conscientiousness. Positive attitude toward agreeableness predicted the increase of the number of posts written by friends on user’s wall unlike trait agreeableness. Attitudes toward traits are argued to affect social environment governed by an individual: one may select those social relationships and partners that fit better one’s attitudes toward traits. This, in turn, may affect actions of other people towards the given individual including those of online behaviour.

  7. Engineering online and in-person social networks to sustain physical activity: application of a conceptual model.

    Science.gov (United States)

    Rovniak, Liza S; Sallis, James F; Kraschnewski, Jennifer L; Sciamanna, Christopher N; Kiser, Elizabeth J; Ray, Chester A; Chinchilli, Vernon M; Ding, Ding; Matthews, Stephen A; Bopp, Melissa; George, Daniel R; Hovell, Melbourne F

    2013-08-14

    High rates of physical inactivity compromise the health status of populations globally. Social networks have been shown to influence physical activity (PA), but little is known about how best to engineer social networks to sustain PA. To improve procedures for building networks that shape PA as a normative behavior, there is a need for more specific hypotheses about how social variables influence PA. There is also a need to integrate concepts from network science with ecological concepts that often guide the design of in-person and electronically-mediated interventions. Therefore, this paper: (1) proposes a conceptual model that integrates principles from network science and ecology across in-person and electronically-mediated intervention modes; and (2) illustrates the application of this model to the design and evaluation of a social network intervention for PA. A conceptual model for engineering social networks was developed based on a scoping literature review of modifiable social influences on PA. The model guided the design of a cluster randomized controlled trial in which 308 sedentary adults were randomly assigned to three groups: WalkLink+: prompted and provided feedback on participants' online and in-person social-network interactions to expand networks for PA, plus provided evidence-based online walking program and weekly walking tips; WalkLink: evidence-based online walking program and weekly tips only; Minimal Treatment Control: weekly tips only. The effects of these treatment conditions were assessed at baseline, post-program, and 6-month follow-up. The primary outcome was accelerometer-measured PA. Secondary outcomes included objectively-measured aerobic fitness, body mass index, waist circumference, blood pressure, and neighborhood walkability; and self-reported measures of the physical environment, social network environment, and social network interactions. The differential effects of the three treatment conditions on primary and secondary

  8. Engineering online and in-person social networks to sustain physical activity: application of a conceptual model

    Science.gov (United States)

    2013-01-01

    Background High rates of physical inactivity compromise the health status of populations globally. Social networks have been shown to influence physical activity (PA), but little is known about how best to engineer social networks to sustain PA. To improve procedures for building networks that shape PA as a normative behavior, there is a need for more specific hypotheses about how social variables influence PA. There is also a need to integrate concepts from network science with ecological concepts that often guide the design of in-person and electronically-mediated interventions. Therefore, this paper: (1) proposes a conceptual model that integrates principles from network science and ecology across in-person and electronically-mediated intervention modes; and (2) illustrates the application of this model to the design and evaluation of a social network intervention for PA. Methods/Design A conceptual model for engineering social networks was developed based on a scoping literature review of modifiable social influences on PA. The model guided the design of a cluster randomized controlled trial in which 308 sedentary adults were randomly assigned to three groups: WalkLink+: prompted and provided feedback on participants’ online and in-person social-network interactions to expand networks for PA, plus provided evidence-based online walking program and weekly walking tips; WalkLink: evidence-based online walking program and weekly tips only; Minimal Treatment Control: weekly tips only. The effects of these treatment conditions were assessed at baseline, post-program, and 6-month follow-up. The primary outcome was accelerometer-measured PA. Secondary outcomes included objectively-measured aerobic fitness, body mass index, waist circumference, blood pressure, and neighborhood walkability; and self-reported measures of the physical environment, social network environment, and social network interactions. The differential effects of the three treatment conditions on

  9. Indigenous development and networking of online radon monitors in the underground uranium mine

    International Nuclear Information System (INIS)

    Gaware, J.J.; Sahoo, B.K.; Sapra, B.K.; Mayya, Y.S.

    2010-01-01

    Full text: There has been a long standing demand for online monitoring of radon level in various locations of underground uranium mine for taking care of radiological protection to workers. Nowadays, radon ( 222 Rn) monitors, based on semiconductor detector are increasingly employed for radon monitoring in environment. However, such instruments have some limitations such as (i) requirement of additional dryer in the sampling path, (ii) cannot be connected to a online data logging and monitoring network, (iii) not cost effective for large number of installations. Due to need for dryer, unattended continuous operation of such instruments is not possible particularly in underground uranium mine with humidity in the range of 80 to 98 %. So it is required to develop radon monitors which overcome the above limitations so that large number of monitors can be deployed in the uranium mine. Often radon progeny is electrostatically collected on the detector surface to increase the sensitivity. However, the collection efficiency is highly dependent upon the humidity and trace gas concentration in the sample gas due to charge neutralization effect. This effect can be minimized by applying a high electric field throughout the detector's chamber volume. This cannot be achieved using planner silicon PIN diode (area ∼ 4 cm 2 ) due to its inherent size limitations. This is because the electric field, in case of small inner electrode, falls off rapidly towards the outer electrode. Hence, an instrument has been indigenously developed by designing an annular cylindrical chamber with larger inner cathode (area = 140 cm 2 ) by employing flexible ZnS:Ag sheet (scintillation detector). With this design, the high sensitivity of 2.8 cph/Bqm -3 has been accomplished with the nominal deviation within 15% for vast change in humidity of 5% to 95%. In this instrument, although the alpha spectroscopy is not possible, the high sensitivity of the instruments makes it possible to achieve the MDL as

  10. HealthTrust: a social network approach for retrieving online health videos.

    Science.gov (United States)

    Fernandez-Luque, Luis; Karlsen, Randi; Melton, Genevieve B

    2012-01-31

    Social media are becoming mainstream in the health domain. Despite the large volume of accurate and trustworthy health information available on social media platforms, finding good-quality health information can be difficult. Misleading health information can often be popular (eg, antivaccination videos) and therefore highly rated by general search engines. We believe that community wisdom about the quality of health information can be harnessed to help create tools for retrieving good-quality social media content. To explore approaches for extracting metrics about authoritativeness in online health communities and how these metrics positively correlate with the quality of the content. We designed a metric, called HealthTrust, that estimates the trustworthiness of social media content (eg, blog posts or videos) in a health community. The HealthTrust metric calculates reputation in an online health community based on link analysis. We used the metric to retrieve YouTube videos and channels about diabetes. In two different experiments, health consumers provided 427 ratings of 17 videos and professionals gave 162 ratings of 23 videos. In addition, two professionals reviewed 30 diabetes channels. HealthTrust may be used for retrieving online videos on diabetes, since it performed better than YouTube Search in most cases. Overall, of 20 potential channels, HealthTrust's filtering allowed only 3 bad channels (15%) versus 8 (40%) on the YouTube list. Misleading and graphic videos (eg, featuring amputations) were more commonly found by YouTube Search than by searches based on HealthTrust. However, some videos from trusted sources had low HealthTrust scores, mostly from general health content providers, and therefore not highly connected in the diabetes community. When comparing video ratings from our reviewers, we found that HealthTrust achieved a positive and statistically significant correlation with professionals (Pearson r₁₀ = .65, P = .02) and a trend toward

  11. Examining the Feasibility and Acceptability of an Online Yoga Class for Mood Disorders: A MoodNetwork Study.

    Science.gov (United States)

    Uebelacker, Lisa; Dufour, Steven C; Dinerman, Jacob G; Walsh, Samantha L; Hearing, Casey; Gillette, Lee T; Deckersbach, Thilo; Nierenberg, Andrew A; Weinstock, Lauren; Sylvia, Louisa G

    2018-01-01

    Despite ongoing advances in the treatment of mood disorders, a substantial proportion of people diagnosed with major depression or bipolar disorder remain symptomatic over time. Yoga, which has been shown to reduce stress and depressive symptoms, as well as to improve overall quality of life, shows promise as an adjunctive treatment. However, dissemination of yoga for clinical populations remains challenging. The purpose of this pilot study was to test the feasibility and acceptability of an online yoga intervention for individuals with mood disorders. In total, 56 adults who reported being diagnosed with a mood disorder (bipolar disorder, major depressive disorder, cyclothymia, or schizoaffective disorder) were recruited from MoodNetwork, an online community of individuals with mood disorders. A feedback survey and a measure of positive and negative affect were administered before and after a 30-minute online Hatha yoga class. In total, 44 individuals (78.6%) completed all components of the yoga class. The mean score on a 10-point Likert scale rating how much participants liked the online yoga class was 7.24 (SD=2.40). Most participants (67.9%) reported that they would be "somewhat likely" or "very likely" to participate in an online yoga program again. There was a statistically significant decrease in negative affect after completing the class (t=-6.05; P0.10). These preliminary data support the utility of online yoga tailored specifically for people with mood disorders as a possible adjunctive intervention that warrants further investigation.

  12. Scaling-Up Youth-Led Social Justice Efforts through an Online School-Based Social Network.

    Science.gov (United States)

    Kornbluh, Mariah; Neal, Jennifer Watling; Ozer, Emily J

    2016-06-01

    The exploration of social networking sites (SNS) in promoting social change efforts offers great potential within the field of community psychology. Online communities on SNS provide opportunities for bridging across groups, thus fostering the exchange of novel ideas and practices. Currently, there have only been limited efforts to examine SNS within the context of youth-led efforts. To explore the potential of SNS to facilitate the diffusion of social justice efforts between distinct youth groups, we linked three school-based youth-led participatory action research projects involving 54 high school students through a SNS. This study offers an innovative methodological approach and framework, utilizing social network analysis and strategic sampling of key student informants to investigate what individual behaviors and online network features predict student adoption of social change efforts. Findings highlight prospective facilitators and barriers to diffusion processes within a youth-led online network, as well as key constructs that may inform future research. We conclude by providing suggestions for scholars and practitioners interested in examining how SNS can be used to enhance the diffusion of social justice strategies, youth-led engagement efforts, and large-scale civic organizing. © Society for Community Research and Action 2016.

  13. Support or competition? How online social networks increase physical activity: A randomized controlled trial

    Directory of Open Access Journals (Sweden)

    Jingwen Zhang, PhD

    2016-12-01

    Full Text Available To identify what features of online social networks can increase physical activity, we conducted a 4-arm randomized controlled trial in 2014 in Philadelphia, PA. Students (n = 790, mean age = 25.2 at an university were randomly assigned to one of four conditions composed of either supportive or competitive relationships and either with individual or team incentives for attending exercise classes. The social comparison condition placed participants into 6-person competitive networks with individual incentives. The social support condition placed participants into 6-person teams with team incentives. The combined condition with both supportive and competitive relationships placed participants into 6-person teams, where participants could compare their team's performance to 5 other teams' performances. The control condition only allowed participants to attend classes with individual incentives. Rewards were based on the total number of classes attended by an individual, or the average number of classes attended by the members of a team. The outcome was the number of classes that participants attended. Data were analyzed using multilevel models in 2014. The mean attendance numbers per week were 35.7, 38.5, 20.3, and 16.8 in the social comparison, the combined, the control, and the social support conditions. Attendance numbers were 90% higher in the social comparison and the combined conditions (mean = 1.9, SE = 0.2 in contrast to the two conditions without comparison (mean = 1.0, SE = 0.2 (p = 0.003. Social comparison was more effective for increasing physical activity than social support and its effects did not depend on individual or team incentives.

  14. Motives for Online Friending and Following: The Dark Side of Social Network Site Connections

    Directory of Open Access Journals (Sweden)

    Jaap W. Ouwerkerk

    2016-08-01

    Full Text Available Motives for “friending,” following, or connecting with others on social network sites are often positive, but darker motives may also play an important role. A survey with a novel Following Motives Scale (FMS demonstrates accordingly that positive, sociable motives (i.e., others providing a valued source for humor and information, others sharing a common background, as well as relationship maintenance and inspirational motives (i.e., others providing a target for upward social comparison can be distinguished from darker motives related to insecurity (i.e., others providing reassurance, preference for online interaction, mediated voyeurism, as well as social obligation, and even darker antisocial motives related to self-enhancement (i.e., others providing a target for downward social comparison, competition, schadenfreude, gossip, as well as “hate-following”. Results show that lower self-esteem and higher levels of need for popularity, narcissism, and dispositional schadenfreude characterize users with stronger dark side motives, whereas users with more sociable motives report more satisfaction with life, thereby providing construct validity for the novel scale. Convergent validity is demonstrated by positive relations between following motives and both time spent and following counts on different social network sites. Moreover, an embedded experiment shows that antisocial motives predicted acceptance of a Facebook friendship request from a male or female high school acquaintance who suffered a setback in the domain of appearance or status (i.e., a convenient source for self-enhancement, thereby providing additional convergent validity for the Antisocial Motives subscale.

  15. The Influence of Culture on the Expression of Emotions in Online Social Networks

    Directory of Open Access Journals (Sweden)

    Cathia PAPI

    2016-12-01

    Full Text Available Seeking to understand the influence of culture on the expression of emotions in online social networks, we analyzed four Facebook groups – two from Quebec, Canada and two from Colombia – created following unexpected deaths. Comparison of the messages posted in these groups reveals a stronger tendency to maintain a virtual relationship with the deceased by Canadians than by Columbians. Among the former, the deceased is more often asked to and thanked for watching over the living, and testimonies of love addressed to the deceased are more numerous than among the latter. Among the latter, the strength of the links maintained with the deceased justifying the present pain and evocation of the mourners’ Catholic beliefs are relatively more frequent. Finally, while the Canadian Quebecers’ messages would presumably be written in French and those of Colombians in Spanish, it is interesting to observe a certain presence of English to express feelings of loss and love in the four groups, as well as a certain affinity between North American virtual bereavement practices and those seemingly more characteristic of women, the main contributors in all four groups.

  16. Health social networks as online life support groups for patients with cardiovascular diseases.

    Science.gov (United States)

    Medina, Edhelmira Lima; Loques Filho, Orlando; Mesquita, Cláudio Tinoco

    2013-08-01

    The number of patients who use the internet in search for information that might improve their health conditions has increased. Among them, those looking for virtual environments to share experiences, doubts, opinions, and emotions, and to foster relationships aimed at giving and getting support stand out. Therefore, there is an increasing need to assess how those environments can affect the patients' health. This study was aimed at identifying scientific studies on the proliferation and impact of virtual communities, known as health social networks or online support groups,directed to cardiovascular diseases, which might be useful to patients with certain conditions, providing them with information and emotional support. A systematic review of the literature was conducted with articles published from 2007 to 2012, related to cardiovascular diseases and collected from the following databases: PubMed; Association for Computing Machinery(ACM); and Institute of Electrical and Electronics Engineers (IEEE). Four articles meeting the inclusion criteria were selected. The results were interesting and relevant from the health viewpoint, identifying therapeutic benefits, such as provision of emotional support, greater compliance to treatment, and information sharing on diseases and on life experiences.

  17. Health Social Networks as Online Life Support Groups for Patients With Cardiovascular Diseases

    International Nuclear Information System (INIS)

    Medina, Edhelmira Lima; Loques, Orlando Filho; Mesquita, Cláudio Tinoco

    2013-01-01

    The number of patients who use the internet in search for information that might improve their health conditions has increased. Among them, those looking for virtual environments to share experiences, doubts, opinions, and emotions, and to foster relationships aimed at giving and getting support stand out. Therefore, there is an increasing need to assess how those environments can affect the patients' health. This study was aimed at identifying scientific studies on the proliferation and impact of virtual communities, known as health social networks or online support groups, directed to cardiovascular diseases, which might be useful to patients with certain conditions, providing them with information and emotional support. A systematic review of the literature was conducted with articles published from 2007 to 2012, related to cardiovascular diseases and collected from the following databases: PubMed; Association for Computing Machinery(ACM); and Institute of Electrical and Electronics Engineers (IEEE). Four articles meeting the inclusion criteria were selected. The results were interesting and relevant from the health viewpoint, identifying therapeutic benefits, such as provision of emotional support, greater compliance to treatment, and information sharing on diseases and on life experiences

  18. Health Social Networks as Online Life Support Groups for Patients With Cardiovascular Diseases

    Energy Technology Data Exchange (ETDEWEB)

    Medina, Edhelmira Lima, E-mail: edhyly@ic.uff.br; Loques, Orlando Filho [Instituto de Computação - Universidade Federal Fluminense, Niterói, RJ (Brazil); Mesquita, Cláudio Tinoco [Hospital Universitário Antônio Pedro - Universidade Federal Fluminense, Niterói, RJ (Brazil)

    2013-08-15

    The number of patients who use the internet in search for information that might improve their health conditions has increased. Among them, those looking for virtual environments to share experiences, doubts, opinions, and emotions, and to foster relationships aimed at giving and getting support stand out. Therefore, there is an increasing need to assess how those environments can affect the patients' health. This study was aimed at identifying scientific studies on the proliferation and impact of virtual communities, known as health social networks or online support groups, directed to cardiovascular diseases, which might be useful to patients with certain conditions, providing them with information and emotional support. A systematic review of the literature was conducted with articles published from 2007 to 2012, related to cardiovascular diseases and collected from the following databases: PubMed; Association for Computing Machinery(ACM); and Institute of Electrical and Electronics Engineers (IEEE). Four articles meeting the inclusion criteria were selected. The results were interesting and relevant from the health viewpoint, identifying therapeutic benefits, such as provision of emotional support, greater compliance to treatment, and information sharing on diseases and on life experiences.

  19. On-line node fault injection training algorithm for MLP networks: objective function and convergence analysis.

    Science.gov (United States)

    Sum, John Pui-Fai; Leung, Chi-Sing; Ho, Kevin I-J

    2012-02-01

    Improving fault tolerance of a neural network has been studied for more than two decades. Various training algorithms have been proposed in sequel. The on-line node fault injection-based algorithm is one of these algorithms, in which hidden nodes randomly output zeros during training. While the idea is simple, theoretical analyses on this algorithm are far from complete. This paper presents its objective function and the convergence proof. We consider three cases for multilayer perceptrons (MLPs). They are: (1) MLPs with single linear output node; (2) MLPs with multiple linear output nodes; and (3) MLPs with single sigmoid output node. For the convergence proof, we show that the algorithm converges with probability one. For the objective function, we show that the corresponding objective functions of cases (1) and (2) are of the same form. They both consist of a mean square errors term, a regularizer term, and a weight decay term. For case (3), the objective function is slight different from that of cases (1) and (2). With the objective functions derived, we can compare the similarities and differences among various algorithms and various cases.

  20. Romantic Partner Monitoring After Breakups: Attachment, Dependence, Distress, and Post-Dissolution Online Surveillance via Social Networking Sites.

    Science.gov (United States)

    Fox, Jesse; Tokunaga, Robert S

    2015-09-01

    Romantic relationship dissolution can be stressful, and social networking sites make it difficult to separate from a romantic partner online as well as offline. An online survey (N = 431) tested a model synthesizing attachment, investment model variables, and post-dissolution emotional distress as predictors of interpersonal surveillance (i.e., "Facebook stalking") of one's ex-partner on Facebook after a breakup. Results indicated that anxious attachment predicted relational investment but also seeking relationship alternatives; avoidant attachment was negatively related to investment but positively related to seeking alternatives. Investment predicted commitment, whereas seeking alternatives was negatively related to commitment. Commitment predicted emotional distress after the breakup. Distress predicted partner monitoring immediately following the breakup, particularly for those who did not initiate the breakup, as well as current partner monitoring. Given their affordances, social media are discussed as potentially unhealthy enablers for online surveillance after relationship termination.

  1. Identity Confusion and Materialism Mediate the Relationship Between Excessive Social Network Site Usage and Online Compulsive Buying.

    Science.gov (United States)

    Sharif, Saeed Pahlevan; Khanekharab, Jasmine

    2017-08-01

    This study investigates the mediating role of identity confusion and materialism in the relationship between social networking site (SNS) excessive usage and online compulsive buying among young adults. A total of 501 SNS users aged 17 to 23 years (M = 19.68, SD = 1.65) completed an online survey questionnaire. A serial multiple mediator model was developed and hypotheses were tested using structural equation modeling. The results showed that excessive young adult SNS users had a higher tendency toward compulsive buying online. This was partly because they experienced higher identity confusion and developed higher levels of materialism. Targeted psychological interventions seeking to gradually increase identity clarity to buffer the detrimental effects of SNS usage and identity confusion in young adults are suggested.

  2. Predicting Social Networking Site Use and Online Communication Practices among Adolescents: The Role of Access and Device Ownership

    Directory of Open Access Journals (Sweden)

    Drew P. Cingel

    2014-06-01

    Full Text Available Given adolescents' heavy social media use, this study examined a number of predictors of adolescent social media use, as well as predictors of online communication practices. Using data collected from a national sample of 467 adolescents between the ages of 13 and 17, results indicate that demographics, technology access, and technology ownership are related to social media use and communication practices. Specifically, females log onto and use more constructive com-munication practices on Facebook compared to males. Additionally, adolescents who own smartphones engage in more constructive online communication practices than those who share regular cell phones or those who do not have access to a cell phone. Overall, results imply that ownership of mobile technologies, such as smartphones and iPads, may be more predictive of social networking site use and online communication practices than general ownership of technology.

  3. Predicting Social Networking Site Use and Online Communication Practices among Adolescents: The Role of Access and Device Ownership

    Directory of Open Access Journals (Sweden)

    Drew P. Cingel

    2014-01-01

    Full Text Available Given adolescents' heavy social media use, this study examined a number of predictors of adolescent social media use, as well as predictors of online communication practices. Using data collected from a national sample of 467 adolescents between the ages of 13 and 17, results indicate that demographics, technology access, and technology ownership are related to social media use and communication practices. Specifically, females log onto and use more constructive communication practices on Facebook compared to males. Additionally, adolescents who own smartphones engage in more constructive online communication practices than those who share regular cell phones or those who do not have access to a cell phone. Overall, results imply that ownership of mobile technologies, such as smartphones and iPads, may be more predictive of social networking site use and online communication practices than general ownership of technology.

  4. Televisiekijken, online en offline netwerkkapitaal en eenzaamheid [Exposure to television, online and offline network capital and loneliness

    NARCIS (Netherlands)

    Vergeer, M.R.M.; Pelzer, B.J.

    2009-01-01

    This study sets out to identify relations between the use of television and the Internet, network capital as a resource, social support and loneliness. Using a nationwide sample and structural equation modeling, the assumption that (new) media technology destroys social capital is not supported.

  5. "Supporting Early Career Women in the Geosciences through Online Peer-Mentoring: Lessons from the Earth Science Women's Network (ESWN)"

    Science.gov (United States)

    Holloway, T.; Hastings, M. G.; Barnes, R. T.; Fischer, E. V.; Wiedinmyer, C.; Rodriguez, C.; Adams, M. S.; Marin-Spiotta, E.

    2014-12-01

    The Earth Science Women's Network (ESWN) is an international peer-mentoring organization with over 2000 members, dedicated to career development and community for women across the geosciences. Since its formation in 2002, ESWN has supported the growth of a more diverse scientific community through a combination of online and in-person networking activities. Lessons learned related to online networking and community-building will be presented. ESWN serves upper-level undergraduates, graduate students, professionals in a range of environmental fields, scientists working in federal and state governments, post-doctoral researchers, and academic faculty and scientists. Membership includes women working in over 50 countries, although the majority of ESWN members work in the U.S. ESWN increases retention of women in the geosciences by enabling and supporting professional person-to-person connections. This approach has been shown to reduce feelings of isolation among our members and help build professional support systems critical to career success. In early 2013 ESWN transitioned online activities to an advanced social networking platform that supports discussion threads, group formation, and individual messaging. Prior to that, on-line activities operated through a traditional list-serve, hosted by the National Center for Atmospheric Research (NCAR). The new web center, http://eswnonline.org, serves as the primary forum for members to build connections, seek advice, and share resources. For example, members share job announcements, discuss issues of work-life balance, and organize events at professional conferences. ESWN provides a platform for problem-based mentoring, drawing from the wisdom of colleagues across a range of career stages.

  6. Manifestations of Personality in Online Social Networks: Self-Reported Facebook-Related Behaviors and Observable Profile Information

    OpenAIRE

    Gosling, Samuel D.; Augustine, Adam A; Vazire, Simine; Holtzman, Nicholas; Gaddis, Sam

    2011-01-01

    Despite the enormous popularity of Online Social Networking sites (OSNs; e.g., Facebook and Myspace), little research in psychology has been done on them. Two studies examining how personality is reflected in OSNs revealed several connections between the Big Five personality traits and self-reported Facebook-related behaviors and observable profile information. For example, extraversion predicted not only frequency of Facebook usage (Study 1), but also engagement in the site, with extraverts ...

  7. PREDICTIVE CONTROL OF A BATCH POLYMERIZATION SYSTEM USING A FEEDFORWARD NEURAL NETWORK WITH ONLINE ADAPTATION BY GENETIC ALGORITHM

    Directory of Open Access Journals (Sweden)

    A. Cancelier

    Full Text Available Abstract This study used a predictive controller based on an empirical nonlinear model comprising a three-layer feedforward neural network for temperature control of the suspension polymerization process. In addition to the offline training technique, an algorithm was also analyzed for online adaptation of its parameters. For the offline training, the network was statically trained and the genetic algorithm technique was used in combination with the least squares method. For online training, the network was trained on a recurring basis and only the technique of genetic algorithms was used. In this case, only the weights and bias of the output layer neuron were modified, starting from the parameters obtained from the offline training. From the experimental results obtained in a pilot plant, a good performance was observed for the proposed control system, with superior performance for the control algorithm with online adaptation of the model, particularly with respect to the presence of off-set for the case of the fixed parameters model.

  8. A General Bayesian Network Approach to Analyzing Online Game Item Values and Its Influence on Consumer Satisfaction and Purchase Intention

    Science.gov (United States)

    Lee, Kun Chang; Park, Bong-Won

    Many online game users purchase game items with which to play free-to-play games. Because of a lack of research into which there is no specified framework for categorizing the values of game items, this study proposes four types of online game item values based on an analysis of literature regarding online game characteristics. It then proposes to investigate how online game users perceive satisfaction and purchase intention from the proposed four types of online game item values. Though regression analysis has been used frequently to answer this kind of research question, we propose a new approach, a General Bayesian Network (GBN), which can be performed in an understandable way without sacrificing predictive accuracy. Conventional techniques, such as regression analysis, do not provide significant explanation for this kind of problem because they are fixed to a linear structure and are limited in explaining why customers are likely to purchase game items and if they are satisfied with their purchases. In contrast, the proposed GBN provides a flexible underlying structure based on questionnaire survey data and offers robust decision support on this kind of research question by identifying its causal relationships. To illustrate the validity of GBN in solving the research question in this study, 327 valid questionnaires were analyzed using GBN with what-if and goal-seeking approaches. The experimental results were promising and meaningful in comparison with regression analysis results.

  9. Online support for transgender people: an analysis of forums and social networks.

    Science.gov (United States)

    Cipolletta, Sabrina; Votadoro, Riccardo; Faccio, Elena

    2017-09-01

    Transgender people face a range of personal and social conflicts that strongly influence their well-being. In many cases, the Internet can become the main resource in terms of finding support. The aim of this study was to understand how transgender people give and receive help online. Between 2013 and 2015, 122 online community conversations were collected on Italian forums and Facebook groups involving transgender people, and online interviews were conducted with 16 users of these communities. A qualitative content analysis was conducted by using the software package, NVivo10. The main categories that emerged were: motivations to join an online community, online help, differences between online and offline interactions, status, conflicts and professional help. Results indicate that participation in online communities often derives from the users' need for help. This help can be given by peers who have had similar experiences, and by professionals who participate in the discussions as moderator. The need to test one's own identity, to compare oneself with others and to share one's personal experiences made online communities at risk of exposing users to invalidation and transphobic messages. Administrators and moderators try to ensure the safety of users, and suggest that they ask for professional help offline and/or online when over-specific medical advice was sought. This study confirms that transgender people might find benefit from an online platform of help and support and might minimise distance problems, increase financial convenience and foster disinhibition. © 2017 John Wiley & Sons Ltd.

  10. Understanding Online Health Groups for Depression: Social Network and Linguistic Perspectives

    OpenAIRE

    Xu, Ronghua; Zhang, Qingpeng

    2016-01-01

    Background Mental health problems have become increasingly prevalent in the past decade. With the advance of Web 2.0 technologies, social media present a novel platform for Web users to form online health groups. Members of online health groups discuss health-related issues and mutually help one another by anonymously revealing their mental conditions, sharing personal experiences, exchanging health information, and providing suggestions and support. The conversations in online health groups ...

  11. The Impact of Online Social Networks on Health and Health Systems: A Scoping Review and Case Studies.

    Science.gov (United States)

    Griffiths, Frances; Dobermann, Tim; Cave, Jonathan A K; Thorogood, Margaret; Johnson, Samantha; Salamatian, Kavé; Gomez Olive, Francis X; Goudge, Jane

    2015-12-01

    Interaction through online social networks potentially results in the contestation of prevailing ideas about health and health care, and to mass protest where health is put at risk or health care provision is wanting. Through a review of the academic literature and case studies of four social networking health sites (PatientsLikeMe, Mumsnet, Treatment Action Campaign, and My Pro Ana), we establish the extent to which this phenomenon is documented, seek evidence of the prevalence and character of health-related networks, and explore their structure, function, participants, and impact, seeking to understand how they came into being and how they sustain themselves. Results indicate mass protest is not arising from these established health-related networking platforms. There is evidence of changes in policy following campaigning activity prompted by experiences shared through social networking such as improved National Health Service care for miscarriage (a Mumsnet campaign). Platform owners and managers have considerable power to shape these campaigns. Social networking is also influencing health policy indirectly through increasing awareness and so demand for health care. Transient social networking about health on platforms such as Twitter were not included as case studies but may be where the most radical or destabilizing influence on health care policy might arise.

  12. The Impact of Online Social Networks on Health and Health Systems: A Scoping Review and Case Studies

    Science.gov (United States)

    Griffiths, Frances; Dobermann, Tim; Cave, Jonathan A. K.; Thorogood, Margaret; Johnson, Samantha; Salamatian, Kavé; Gomez Olive, Francis X.; Goudge, Jane

    2015-01-01

    Interaction through online social networks potentially results in the contestation of prevailing ideas about health and health care, and to mass protest where health is put at risk or health care provision is wanting. Through a review of the academic literature and case studies of four social networking health sites (PatientsLikeMe, Mumsnet, Treatment Action Campaign, and My Pro Ana), we establish the extent to which this phenomenon is documented, seek evidence of the prevalence and character of health‐related networks, and explore their structure, function, participants, and impact, seeking to understand how they came into being and how they sustain themselves. Results indicate mass protest is not arising from these established health‐related networking platforms. There is evidence of changes in policy following campaigning activity prompted by experiences shared through social networking such as improved National Health Service care for miscarriage (a Mumsnet campaign). Platform owners and managers have considerable power to shape these campaigns. Social networking is also influencing health policy indirectly through increasing awareness and so demand for health care. Transient social networking about health on platforms such as Twitter were not included as case studies but may be where the most radical or destabilizing influence on health care policy might arise. PMID:27134699

  13. Dynamic neural networks based on-line identification and control of high performance motor drives

    Science.gov (United States)

    Rubaai, Ahmed; Kotaru, Raj

    1995-01-01

    In the automated and high-tech industries of the future, there wil be a need for high performance motor drives both in the low-power range and in the high-power range. To meet very straight demands of tracking and regulation in the two quadrants of operation, advanced control technologies are of a considerable interest and need to be developed. In response a dynamics learning control architecture is developed with simultaneous on-line identification and control. the feature of the proposed approach, to efficiently combine the dual task of system identification (learning) and adaptive control of nonlinear motor drives into a single operation is presented. This approach, therefore, not only adapts to uncertainties of the dynamic parameters of the motor drives but also learns about their inherent nonlinearities. In fact, most of the neural networks based adaptive control approaches in use have an identification phase entirely separate from the control phase. Because these approaches separate the identification and control modes, it is not possible to cope with dynamic changes in a controlled process. Extensive simulation studies have been conducted and good performance was observed. The robustness characteristics of neuro-controllers to perform efficiently in a noisy environment is also demonstrated. With this initial success, the principal investigator believes that the proposed approach with the suggested neural structure can be used successfully for the control of high performance motor drives. Two identification and control topologies based on the model reference adaptive control technique are used in this present analysis. No prior knowledge of load dynamics is assumed in either topology while the second topology also assumes no knowledge of the motor parameters.

  14. Online social networking by patients with diabetes: a qualitative evaluation of communication with Facebook.

    Science.gov (United States)

    Greene, Jeremy A; Choudhry, Niteesh K; Kilabuk, Elaine; Shrank, William H

    2011-03-01

    Several disease-specific information exchanges now exist on Facebook and other online social networking sites. These new sources of knowledge, support, and engagement have become important for patients living with chronic disease, yet the quality and content of the information provided in these digital arenas are poorly understood. To qualitatively evaluate the content of communication in Facebook communities dedicated to diabetes. We identified the 15 largest Facebook groups focused on diabetes management. For each group, we downloaded the 15 most recent "wall posts" and the 15 most recent discussion topics from the 10 largest groups. Four hundred eighty unique users were identified in a series of 690 comments from wall posts and discussion topics. Posts were abstracted and aggregated into a database. Two investigators evaluated the posts, developed a thematic coding scheme, and applied codes to the data. Patients with diabetes, family members, and their friends use Facebook to share personal clinical information, to request disease-specific guidance and feedback, and to receive emotional support. Approximately two-thirds of posts included unsolicited sharing of diabetes management strategies, over 13% of posts provided specific feedback to information requested by other users, and almost 29% of posts featured an effort by the poster to provide emotional support to others as members of a community. Approximately 27% of posts featured some type of promotional activity, generally presented as testimonials advertising non-FDA approved, "natural" products. Clinically inaccurate recommendations were infrequent, but were usually associated with promotion of a specific product or service. Thirteen percent of posts contained requests for personal information from Facebook participants. Facebook provides a forum for reporting personal experiences, asking questions, and receiving direct feedback for people living with diabetes. However, promotional activity and personal

  15. Online social networking and US poison control centers: Facebook as a means of information distribution.

    Science.gov (United States)

    Vo, Kathy; Smollin, Craig

    2015-06-01

    Online social networking services such as Facebook provide a novel medium for the dissemination of public health information by poison control centers in the United States. We performed a cross-sectional study of poison control center Facebook pages to describe and assess the use of this medium. Facebook pages associated with poison control centers were identified during a continuous two-week period from December 24, 2012 to January 7, 2013. Data were extracted from each page, including affiliated poison control center; page duration, measured in years since registration; number of subscribers; number of postings by general toxicological category; and measures of user-generated activity including "likes", "shares", and comments per posting. Among the 56 US poison control centers, 39 Facebook pages were identified, of which 29 were currently active. The total number of active pages has increased by 140% from 2009 to 2013 (average of 25% per year). The total number of all subscribers to active pages was 11,211, ranging from 40 to 2,456 (mean 387, SD 523), equal to 0.006% of all Facebook users in the United States. The number of subscribers per page was associated with page duration, number of postings, and type of postings. The types of toxicological postings were public education (45%), self-promotion (28%), childhood safety (12%), drugs of abuse (8%), environmental poisonings (6%), and general overdoses (1%). Slightly over half of all poison control centers in the United States are supplementing their outreach and education efforts through Facebook. In general, the more active the poison control center on Facebook, the more page followers and follower engagement gained.

  16. The Best of Both Worlds? Online Ties and the Alternating Use of Social Network Sites in the Context of Migration

    Directory of Open Access Journals (Sweden)

    Jens F. Binder

    2014-12-01

    Full Text Available While an ever-growing body of research is concerned with user behavior on individual social network sites (SNSs—mostly Facebook—studies addressing an alternating use of two or more SNS are rare. Here, we investigate the relationship between alternating SNS use and social capital in the context of migration. Alternating SNS use avoids some of the problems associated with large networks located on one site; in particular the management of different social or cultural spheres. Not only does this strategy hold potential for increased social capital, it also provides a particular incentive for migrants faced with the challenge of staying in touch with back home and managing a new social environment. Two survey studies are presented that focus on the relationship between alternating SNS use and online ties in a migrant context involving Indian nationals. Study 1 looked at migration within India, whereas Study 2 compared international with domestic SNS users. In both studies, alternating SNS use added to the prediction of online network size and accounted for differences in network size found for migrant and non-migrant users. Differences were due to the number of peripheral ties, rather than core ties. Findings suggest that alternating SNS use may constitute a compensatory strategy that helps to overcome lower levels of socializing represented through a single SNS.

  17. A Qualitative Study to Examine Feasibility and Design of an Online Social Networking Intervention to Increase Physical Activity in Teenage Girls.

    Science.gov (United States)

    Van Kessel, Gisela; Kavanagh, Madeleine; Maher, Carol

    2016-01-01

    Online social networks present wide-reaching and flexible platforms through which to deliver health interventions to targeted populations. This study used a social marketing approach to explore teenage girls' perceptions of physical activity and the potential use of online social networks to receive a physical activity intervention. Six focus groups were conducted with 19 Australian teenage girls (ages 13 to 18 years) with varying levels of physical activity and socioeconomic status. A semi-structured format was used, with groups discussion transcribed verbatim. Content analysis identified emergent themes, with triangulation and memos used to ensure accuracy. Physical activity was most appealing when it emphasised sport, exercise and fitness, along with opportunities for socialisation with friends and self-improvement. Participants were receptive to delivery of a physical activity intervention via online social networks, with Facebook the most widely reported site. Participants commonly accessed online social networks via mobile devices and particularly smartphones. Undesirable features included promotion of physical activity in terms of walking; use of cartoon imagery; use of humour; and promotion of the intervention via schools, each of which were considered "uncool". Participants noted that their parents were likely to be supportive of them using an online social networking physical activity intervention, particularly if not promoted as a weight loss intervention. This study identified key features likely to increase the feasibility and retention of an online social networking physical activity intervention for teenage girls. Guidelines for the design of interventions for teenage girls are provided for future applications.

  18. A Qualitative Study to Examine Feasibility and Design of an Online Social Networking Intervention to Increase Physical Activity in Teenage Girls.

    Directory of Open Access Journals (Sweden)

    Gisela Van Kessel

    Full Text Available Online social networks present wide-reaching and flexible platforms through which to deliver health interventions to targeted populations. This study used a social marketing approach to explore teenage girls' perceptions of physical activity and the potential use of online social networks to receive a physical activity intervention.Six focus groups were conducted with 19 Australian teenage girls (ages 13 to 18 years with varying levels of physical activity and socioeconomic status. A semi-structured format was used, with groups discussion transcribed verbatim. Content analysis identified emergent themes, with triangulation and memos used to ensure accuracy.Physical activity was most appealing when it emphasised sport, exercise and fitness, along with opportunities for socialisation with friends and self-improvement. Participants were receptive to delivery of a physical activity intervention via online social networks, with Facebook the most widely reported site. Participants commonly accessed online social networks via mobile devices and particularly smartphones. Undesirable features included promotion of physical activity in terms of walking; use of cartoon imagery; use of humour; and promotion of the intervention via schools, each of which were considered "uncool". Participants noted that their parents were likely to be supportive of them using an online social networking physical activity intervention, particularly if not promoted as a weight loss intervention.This study identified key features likely to increase the feasibility and retention of an online social networking physical activity intervention for teenage girls. Guidelines for the design of interventions for teenage girls are provided for future applications.

  19. How social network analysis can be used to monitor online collaborative learning and guide an informed intervention.

    Science.gov (United States)

    Saqr, Mohammed; Fors, Uno; Tedre, Matti; Nouri, Jalal

    2018-01-01

    To ensure online collaborative learning meets the intended pedagogical goals (is actually collaborative and stimulates learning), mechanisms are needed for monitoring the efficiency of online collaboration. Various studies have indicated that social network analysis can be particularly effective in studying students' interactions in online collaboration. However, research in education has only focused on the theoretical potential of using SNA, not on the actual benefits they achieved. This study investigated how social network analysis can be used to monitor online collaborative learning, find aspects in need of improvement, guide an informed intervention, and assess the efficacy of intervention using an experimental, observational repeated-measurement design in three courses over a full-term duration. Using a combination of SNA-based visual and quantitative analysis, we monitored three SNA constructs for each participant: the level of interactivity, the role, and position in information exchange, and the role played by each participant in the collaboration. On the group level, we monitored interactivity and group cohesion indicators. Our monitoring uncovered a non-collaborative teacher-centered pattern of interactions in the three studied courses as well as very few interactions among students, limited information exchange or negotiation, and very limited student networks dominated by the teacher. An intervention based on SNA-generated insights was designed. The intervention was structured into five actions: increasing awareness, promoting collaboration, improving the content, preparing teachers, and finally practicing with feedback. Evaluation of the intervention revealed that it has significantly enhanced student-student interactions and teacher-student interactions, as well as produced a collaborative pattern of interactions among most students and teachers. Since efficient and communicative activities are essential prerequisites for successful content

  20. An experimental study of the Online Information Paradox: Does en-route information improve road network performance?

    Science.gov (United States)

    Wijayaratna, Kasun P; Dixit, Vinayak V; Denant-Boemont, Laurent; Waller, S Travis

    2017-01-01

    This study investigates the empirical presence of a theoretical transportation paradox, defined as the "Online Information Paradox" (OIP). The paradox suggests that, for certain road networks, the provision of online information deteriorate travel conditions for all users of that network relative to the situation where no online information is provided to users. The analytical presence of the paradox was derived for a specific network structure by using two equilibrium models, the first being the Expected User Equilibrium (EUE) solution (no information scenario) and the other being the User Equilibrium with Recourse (UER) solution (with information scenario). An incentivised computerised route choice game was designed using the concepts of experimental economics and administered in a controlled laboratory environment to investigate the physical presence of the paradox. Aggregate statistics of path flows and Total System Travel Costs (TSTC) were used to compare the experimental results with the theoretical findings. A total of 12 groups of 12 participants completed the experiment and the OIP and the occurrence of the OIP being significant was observed in 11 of the 12 cases. Though information increased travel costs for users on average, it reduced the volatility of travel costs experienced in the no information scenario indicating that information can achieve a more reliable system. Further replications of similar experiments and more importantly field based identification of the phenomena will force transport professionals to be aware of the emergence of the paradox. In addition, studies such as this emphasise the need for the adoption of adaptive traffic assignment techniques to appropriately model the acquisition of information on a road network.

  1. An experimental study of the Online Information Paradox: Does en-route information improve road network performance?

    Directory of Open Access Journals (Sweden)

    Kasun P Wijayaratna

    Full Text Available This study investigates the empirical presence of a theoretical transportation paradox, defined as the "Online Information Paradox" (OIP. The paradox suggests that, for certain road networks, the provision of online information deteriorate travel conditions for all users of that network relative to the situation where no online information is provided to users. The analytical presence of the paradox was derived for a specific network structure by using two equilibrium models, the first being the Expected User Equilibrium (EUE solution (no information scenario and the other being the User Equilibrium with Recourse (UER solution (with information scenario. An incentivised computerised route choice game was designed using the concepts of experimental economics and administered in a controlled laboratory environment to investigate the physical presence of the paradox. Aggregate statistics of path flows and Total System Travel Costs (TSTC were used to compare the experimental results with the theoretical findings. A total of 12 groups of 12 participants completed the experiment and the OIP and the occurrence of the OIP being significant was observed in 11 of the 12 cases. Though information increased travel costs for users on average, it reduced the volatility of travel costs experienced in the no information scenario indicating that information can achieve a more reliable system. Further replications of similar experiments and more importantly field based identification of the phenomena will force transport professionals to be aware of the emergence of the paradox. In addition, studies such as this emphasise the need for the adoption of adaptive traffic assignment techniques to appropriately model the acquisition of information on a road network.

  2. Connecting to young adults: an online social network survey of beliefs and attitudes associated with prescription opioid misuse among college students.

    Science.gov (United States)

    Lord, Sarah; Brevard, Julie; Budman, Simon

    2011-01-01

    A survey of motives and attitudes associated with patterns of nonmedical prescription opioid medication use among college students was conducted on Facebook, a popular online social networking Web site. Response metrics for a 2-week random advertisement post, targeting students who had misused prescription medications, surpassed typical benchmarks for online marketing campaigns and yielded 527 valid surveys. Respondent characteristics, substance use patterns, and use motives were consistent with other surveys of prescription opioid use among college populations. Results support the potential of online social networks to serve as powerful vehicles to connect with college-aged populations about their drug use. Limitations of the study are noted.

  3. Development of an artificial neural network model for on-line thermal margin estimation of a nuclear reactor core

    International Nuclear Information System (INIS)

    Kim, Hyun Koon

    1992-02-01

    One of the key safety parameters related to thermal margin in a Pressurized Water Reactor (PWR) core, is Departure from Nucleate Boiling Ratio (DNBR), which is to be assessed and continuously monitored during operation via either an analog or a digital monitoring system. The digital monitoring system, in general, allows more thermal margin than the analog system through the on-line computation of DNBR using the measured parameters as inputs to a simplified, fast running computer code. The purpose of this thesis is to develop an advanced method for on-line DNBR estimation by introducing an artifactual neural network model for best-estimation of DNBR at the given reactor operating conditions. the neural network model, consisting of three layers with five operating parameters in the input layer, provides real-time prediction accuracy of DNBR by training the network against the detailed simulation results for various operating conditions. The overall training procedure is developed to learn the characteristics of DNBR behaviour in the reactor core. First, a set of random combination of input variables is generated by Latin Hypercube Sampling technique performed on a wide range of input parameters. Second, the target values of DNBR to be referenced for training are calculated using a detailed simulation code, COBRA-IV. Third, the optimized training input data are selected. Then, training is performed using an Error Back Propagation algorithm. After completion of training, the network is tested on the examining data set in order to investigate the generalization capability of the network responses for the steady state operating condition as well as for the transient situations where DNB is of a primary concern. The test results show that the values of DNBR predicted by the neural network are maintained at a high level of accuracy for the steady state condition, and are in good agreements with the transient situation, although slightly conservative as compared to those

  4. Things online social networking can take away: Reminders of social networking sites undermine the desirability of offline socializing and pleasures.

    Science.gov (United States)

    Li, Shiang-Shiang; Chang, Yevvon Yi-Chi; Chiou, Wen-Bin

    2017-04-01

    People are beginning to develop symbiotic relationships with social networking sites (SNSs), which provide users with abundant opportunities for social interaction. We contend that if people perceive SNSs as sources of social connection, the idea of SNSs may reduce the desire to pursue offline social activities and offline pleasures. Experiment 1 demonstrated that priming with SNSs was associated with a weakened desirability of offline social activities and an increased inclination to work alone. Felt relatedness mediated the link between SNS primes and reduced desire to engage in offline social activities. Experiment 2 showed that exposure to SNS primes reduced the desirability of offline socializing and lowered the desire for offline pleasurable experiences as well. Moreover, heavy users were more susceptible to this detrimental effect. We provide the first experimental evidence that the idea of online social networking may modulate users' engagement in offline social activities and offline pleasures. Hence, online social networking may satisfy the need for relatedness but undercut the likelihood of reaping enjoyment from offline social life. © 2016 Scandinavian Psychological Associations and John Wiley & Sons Ltd.

  5. Online Games

    OpenAIRE

    Kerr, Aphra; Ivory, James D.

    2015-01-01

    When we agreed to edit the theme on online games for this Encyclopedia our first question was, “What is meant by online games?” Scholars of games distinguish between nondigital games (such as board games) and digital games, rather than between online and offline games. With networked consoles and smartphones it is becoming harder and harder to find players in the wealthy industrialized countries who play “offline” digital games. Most games developers now include ...

  6. Social networking site (SNS) use by adolescent mothers: Can social support and social capital be enhanced by online social networks? - A structured review of the literature.

    Science.gov (United States)

    Nolan, Samantha; Hendricks, Joyce; Ferguson, Sally; Towell, Amanda

    2017-05-01

    to critically appraise the available literature and summarise the evidence relating to adolescent mothers' use of social networking sites in terms of any social support and social capital they may provide and to identify areas for future exploration. social networking sites have been demonstrated to provide social support to marginalised individuals and provide psycho-social benefits to members of such groups. Adolescent mothers are at risk of; social marginalisation; anxiety disorders and depressive symptoms; and poorer health and educational outcomes for their children. Social support has been shown to benefit adolescent mothers thus online mechanisms require consideration. a review of original research articles METHOD: key terms and Boolean operators identified research reports across a 20-year timeframe pertaining to the area of enquiry in: CINAHL, Cochrane Library, Medline, Scopus, ERIC, ProQuest, PsychINFO, Web of Science, Health Collection (Informit) and Google Scholar databases. Eight original research articles met the inclusion criteria for this review. studies demonstrate that adolescent mothers actively search for health information using the Internet and social networking sites, and that social support and social capital can be attributed to their use of specifically created online groups from within targeted health interventions. Use of a message board forum for pregnant and parenting adolescents also demonstrates elements of social support. There are no studies to date pertaining to adolescent mothers' use of globally accessible social networking sites in terms of social support provision and related outcomes. further investigation is warranted to explore the potential benefits of adolescent mothers' use of globally accessible social networking sites in terms of any social support provision and social capital they may provide. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Redes sociales online y su utilización para mejorar las habilidades sociales en jóvenes con discapacidad (Online social networks and using them to improve social skills in young people with disabilities

    Directory of Open Access Journals (Sweden)

    Raquel Suriá Martínez

    2012-12-01

    Full Text Available In recent years, online social networks have introduced profound changes in our environment and new ways of relating to others. The use of social networks is increasingly common, especially among young people, and could further empower young people with limited mobility as a result of a disability. This paper examines the opinions of young people with motor disabilities about the friendships they maintain over online networks and their perceptions regarding how these networks improve their social skills. This is discussed in reference to gender, age and occupation. 68 young people with physical disabilities answered an online questionnaire created for this purpose. The results were analyzed using quantitative methodology. Although we found significant differences based on gender, age and occupation, most of the young people perceived themselves as being highly motivated to use these spaces for personal relationships. They also value the networks in improving their social skills. These results suggest that online social networks are important to young people with physical disabilities in their social relationships, and may also help to design programs aimed at promoting social integration.

  8. Output Feedback-Based Boundary Control of Uncertain Coupled Semilinear Parabolic PDE Using Neurodynamic Programming.

    Science.gov (United States)

    Talaei, Behzad; Jagannathan, Sarangapani; Singler, John

    2018-04-01

    In this paper, neurodynamic programming-based output feedback boundary control of distributed parameter systems governed by uncertain coupled semilinear parabolic partial differential equations (PDEs) under Neumann or Dirichlet boundary control conditions is introduced. First, Hamilton-Jacobi-Bellman (HJB) equation is formulated in the original PDE domain and the optimal control policy is derived using the value functional as the solution of the HJB equation. Subsequently, a novel observer is developed to estimate the system states given the uncertain nonlinearity in PDE dynamics and measured outputs. Consequently, the suboptimal boundary control policy is obtained by forward-in-time estimation of the value functional using a neural network (NN)-based online approximator and estimated state vector obtained from the NN observer. Novel adaptive tuning laws in continuous time are proposed for learning the value functional online to satisfy the HJB equation along system trajectories while ensuring the closed-loop stability. Local uniformly ultimate boundedness of the closed-loop system is verified by using Lyapunov theory. The performance of the proposed controller is verified via simulation on an unstable coupled diffusion reaction process.

  9. An online method for lithium-ion battery remaining useful life estimation using importance sampling and neural networks

    International Nuclear Information System (INIS)

    Wu, Ji; Zhang, Chenbin; Chen, Zonghai

    2016-01-01

    Highlights: • An online RUL estimation method for lithium-ion battery is proposed. • RUL is described by the difference among battery terminal voltage curves. • A feed forward neural network is employed for RUL estimation. • Importance sampling is utilized to select feed forward neural network inputs. - Abstract: An accurate battery remaining useful life (RUL) estimation can facilitate the design of a reliable battery system as well as the safety and reliability of actual operation. A reasonable definition and an effective prediction algorithm are indispensable for the achievement of an accurate RUL estimation result. In this paper, the analysis of battery terminal voltage curves under different cycle numbers during charge process is utilized for RUL definition. Moreover, the relationship between RUL and charge curve is simulated by feed forward neural network (FFNN) for its simplicity and effectiveness. Considering the nonlinearity of lithium-ion charge curve, importance sampling (IS) is employed for FFNN input selection. Based on these results, an online approach using FFNN and IS is presented to estimate lithium-ion battery RUL in this paper. Experiments and numerical comparisons are conducted to validate the proposed method. The results show that the FFNN with IS is an accurate estimation method for actual operation.

  10. The new alchemy: Online networking, data sharing and research activity distribution tools for scientists [version 1; referees: 2 approved

    Directory of Open Access Journals (Sweden)

    Antony J. Williams

    2017-08-01

    Full Text Available There is an abundance of free online tools accessible to scientists and others that can be used for online networking, data sharing and measuring research impact. Despite this, few scientists know how these tools can be used or fail to take advantage of using them as an integrated pipeline to raise awareness of their research outputs. In this article, the authors describe their experiences with these tools and how they can make best use of them to make their scientific research generally more accessible, extending its reach beyond their own direct networks, and communicating their ideas to new audiences. These efforts have the potential to drive science by sparking new collaborations and interdisciplinary research projects that may lead to future publications, funding and commercial opportunities. The intent of this article is to: describe some of these freely accessible networking tools and affiliated products; demonstrate from our own experiences how they can be utilized effectively; and, inspire their adoption by new users for the benefit of science.

  11. Using online social networks to track a pandemic: A systematic review.

    Science.gov (United States)

    Al-Garadi, Mohammed Ali; Khan, Muhammad Sadiq; Varathan, Kasturi Dewi; Mujtaba, Ghulam; Al-Kabsi, Abdelkodose M

    2016-08-01

    The popularity and proliferation of online social networks (OSNs) have created massive social interaction among users that generate an extensive amount of data. An OSN offers a unique opportunity for studying and understanding social interaction and communication among far larger populations now more than ever before. Recently, OSNs have received considerable attention as a possible tool to track a pandemic because they can provide an almost real-time surveillance system at a less costly rate than traditional surveillance systems. A systematic literature search for studies with the primary aim of using OSN to detect and track a pandemic was conducted. We conducted an electronic literature search for eligible English articles published between 2004 and 2015 using PUBMED, IEEExplore, ACM Digital Library, Google Scholar, and Web of Science. First, the articles were screened on the basis of titles and abstracts. Second, the full texts were reviewed. All included studies were subjected to quality assessment. OSNs have rich information that can be utilized to develop an almost real-time pandemic surveillance system. The outcomes of OSN surveillance systems have demonstrated high correlations with the findings of official surveillance systems. However, the limitation in using OSN to track pandemic is in collecting representative data with sufficient population coverage. This challenge is related to the characteristics of OSN data. The data are dynamic, large-sized, and unstructured, thus requiring advanced algorithms and computational linguistics. OSN data contain significant information that can be used to track a pandemic. Different from traditional surveys and clinical reports, in which the data collection process is time consuming at costly rates, OSN data can be collected almost in real time at a cheaper cost. Additionally, the geographical and temporal information can provide exploratory analysis of spatiotemporal dynamics of infectious disease spread. However, on

  12. Share2Quit: Online Social Network Peer Marketing of Tobacco Cessation Systems.

    Science.gov (United States)

    Sadasivam, Rajani S; Cutrona, Sarah L; Luger, Tana M; Volz, Erik; Kinney, Rebecca; Rao, Sowmya R; Allison, Jeroan J; Houston, Thomas K

    2017-03-01

    Although technology-assisted tobacco interventions (TATIs) are effective, they are underused due to recruitment challenges. We tested whether we could successfully recruit smokers to a TATI using peer marketing through a social network (Facebook). We recruited smokers on Facebook using online advertisements. These recruited smokers (seeds) and subsequent waves of smokers (peer recruits) were provided the Share2Quit peer recruitment Facebook app and other tools. Smokers were incentivized for up to seven successful peer recruitments and had 30 days to recruit from date of registration. Successful peer recruitment was defined as a peer recruited smoker completing the registration on the TATI following a referral. Our primary questions were (1) whether smokers would recruit other smokers and (2) whether peer recruitment would extend the reach of the intervention to harder-to-reach groups, including those not ready to quit and minority smokers. Overall, 759 smokers were recruited (seeds: 190; peer recruits: 569). Fifteen percent (n = 117) of smokers successfully recruited their peers (seeds: 24.7%; peer recruits: 7.7%) leading to four recruitment waves. Compared to seeds, peer recruits were less likely to be ready to quit (peer recruits 74.2% vs. seeds 95.1%), more likely to be male (67.1% vs. 32.9%), and more likely to be African American (23.8% vs. 10.8%) (p marketing quadrupled our engaged smokers and enriched the sample with not-ready-to-quit and African American smokers. Peer recruitment is promising, and our study uncovered several important challenges for future research. This study demonstrates the successful recruitment of smokers to a TATI using a Facebook-based peer marketing strategy. Smokers on Facebook were willing and able to recruit other smokers to a TATI, yielding a large and diverse population of smokers. © The Author 2016. Published by Oxford University Press on behalf of the Society for Research on Nicotine and Tobacco. All rights reserved. For

  13. Learning online social support: an investigation of network information technology based on UTAUT.

    Science.gov (United States)

    Lin, Chieh-Peng; Anol, Bhattacherjee

    2008-06-01

    Extending the unified theory of acceptance and use of technology (UTAUT) model, this study postulates a model of online social support. The model is empirically tested using data from undergraduates in Taiwan regarding their usage of instant messaging (IM). The test results indicate that all model paths are significant, except that the path between online social support and facilitating conditions is insignificant. This study offers limitations and implications.

  14. A network analysis of sexually transmitted diseases and online hookup sites among men who have sex with men.

    Science.gov (United States)

    Chan, Philip A; Crowley, Christina; Rose, Jennifer S; Kershaw, Trace; Tributino, Alec; Montgomery, Madeline C; Almonte, Alexi; Raifman, Julia; Patel, Rupa; Nunn, Amy

    2018-01-04

    Sexually transmitted diseases (STDs) are increasing among gay, bisexual, and other men who have sex with men (MSM). Little is known about the use of websites and mobile phone applications to meet sexual partners ("hookup sites") and association with STD diagnoses. We performed a demographic and behavioral assessment of 415 MSM presenting to the Rhode Island STD clinic. Bivariate and multivariable analyses assessed associations between using hook up sites and testing positive for syphilis, gonorrhea, or chlamydia. Venue-based affiliation networks were created to evaluate hookup sites and their association with STD diagnoses. Among 415 MSM, 78% reported meeting a partner online in the last 12 months, and 25% tested positive for at least one STD. Men who met partners online were more likely to be white (67% versus 54%, p=0.03) and have >10 lifetime partners (87% versus 58%, pTinder (22%). In the multivariable analysis, only Scruff use was associated with testing positive for an STD (OR 2.28, 95% CI 1.09-4.94). However, among men who met partners online, 75% of men diagnosed with an STD had met a sexual partner on Grindr, including 100% of those who were diagnosed with gonorrhea. Use of hookup sites was nearly ubiquitous among MSM undergoing STD screening. Specific hookup sites were significantly associated with STD diagnoses among MSM. Greater efforts are needed to promote STD screening and prevention among MSM who meet partners online. The majority of MSM surveyed at an STD clinic reported using an online application (hookup site) to find sex partners. Use of specific hookup sites may increase risk of an STD diagnosis. However, widespread use of hookup sites offer opportunities for STD screening and prevention messaging.

  15. Online Activities, Digital Media Literacy, and Networked Individualism of Korean Youth

    Science.gov (United States)

    Park, Sora; Kim, Eun-mee; Na, Eun-Yeong

    2015-01-01

    Networked individualism enables Internet users to connect and socialize via their loose and transient multiple networks, whereas digital media literacy is a precondition of effective Internet use. In this study, an attempt has been made to find the link between networked individualism, digital media literacy, and young people's perception of their…

  16. To Enhance Collaborative Learning and Practice Network Knowledge with a Virtualization Laboratory and Online Synchronous Discussion

    Science.gov (United States)

    Hwang, Wu-Yuin; Kongcharoen, Chaknarin; Ghinea, Gheorghita

    2014-01-01

    Recently, various computer networking courses have included additional laboratory classes in order to enhance students' learning achievement. However, these classes need to establish a suitable laboratory where each student can connect network devices to configure and test functions within different network topologies. In this case, the Linux…

  17. 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…

  18. Social Networking Sites in the Classroom: Unveiling New Roles for Teachers and New Approaches to Online Course Design

    Directory of Open Access Journals (Sweden)

    Jorge Eduardo Pineda Hoyos

    2014-12-01

    Full Text Available Web 2.0 tools in general and social networking sites in particular are very popular today in everyday life. However, their use in education has not been explored. This paper reports the findings of the implementation of a web 2.0 tool namely a social networking site as a web support for a face-to-face course. The findings show that the implementation of a web-based environment in a face-to-face course can be viewed from 5 different managerial areas: (1 logistics management, (2 information/knowledge management, (3 communication management, (4 class work extension management and (5 web-based environment easiness of accessibility. The conclusions of the study show that the implementation of the web-based environment unveils new roles for teachers and new approaches to design online or blended courses.

  19. Predicting non-linear dynamics by stable local learning in a recurrent spiking neural network.

    Science.gov (United States)

    Gilra, Aditya; Gerstner, Wulfram

    2017-11-27

    The brain needs to predict how the body reacts to motor commands, but how a network of spiking neurons can learn non-linear body dynamics using local, online and stable learning rules is unclear. Here, we present a supervised learning scheme for the feedforward and recurrent connections in a network of heterogeneous spiking neurons. The error in the output is fed back through fixed random connections with a negative gain, causing the network to follow the desired dynamics. The rule for Feedback-based Online Local Learning Of Weights (FOLLOW) is local in the sense that weight changes depend on the presynaptic activity and the error signal projected onto the postsynaptic neuron. We provide examples of learning linear, non-linear and chaotic dynamics, as well as the dynamics of a two-link arm. Under reasonable approximations, we show, using the Lyapunov method, that FOLLOW learning is uniformly stable, with the error going to zero asymptotically.

  20. A design of fault tolerant flight control systems for sensor and actuator failures using on-line learning neural networks

    Science.gov (United States)

    An, Younghwan

    The research in this document focuses on the performance of a neural network-based fault tolerant system within a flight control system. This fault tolerant flight control system integrates sensor and actuator failure detection, identification, and accommodation (SFDIA and AFDIA). The SFDIA task is achieved by incorporating a main neural network (MNN) and a set of n decentralized neural networks (DNNs) for a system with n sensors assumed to be without physical redundancy. Particularly, the purpose of the MNN is to detect a wide variety of sensor failures while the purpose of the DNNs is to identify the particular sensor that has failed and accommodate for the failure. The AFDIA scheme also implements a MNN with three neural network controllers (NNCs). The function of NNCs is to regain equilibrium and to compensate for the pitching, rolling, and yawing moments induced by the failure. The NNs are trained on-line using the Extended Back-Propagation Algorithm (EBPA). Because of the on-line learning, neural estimators and controllers have the capability of adapting to changes in the aircraft dynamics and/or modeling discrepancies between the actual aircraft and its mathematical model. This factor makes neural estimators and controllers an attractive option for fault tolerant flight control system. Particular emphasis is placed in this study toward improving the performance of the SFDIA scheme in the presence of ramp-type soft failures which are hard to detect as well as achieving an efficient integration between SFDIA and AFDIA without degradation of performance in terms of false alarm rates and incorrect failure identification.

  1. The ART of Social Networking: How SART member clinics are connecting with patients online

    Science.gov (United States)

    OMURTAG, Kenan; JIMENEZ, Patricia T.; RATTS, Valerie; ODEM, Randall; COOPER, Amber R.

    2013-01-01

    Objective To study and describe the use of social networking websites among SART member clinics Design Cross-sectional study Setting University Based Practice Patients Not Applicable Interventions Not Applicable Main Outcome Measure Prevalence of social networking websites among SART member clinics and evaluation of content, volume and location (i.e mandated state, region) using multivariate regression analysis Results 384 SART registered clinics and 1,382 social networking posts were evaluated. Of the clinics, 96% have a website and 30% link to a social networking website. The majority of clinics (89%) with social networking websites were affiliated with non-academic centers. Social networking posts mostly provide information (31%) and/or advertise (28%), while the remaining offer support (19%) or are irrelevant (17%) to the target audience. Only 5% of posts involved patients requesting information. Clinic volume correlates with the presence of a clinic website and a social networking website (psocial networking website like Facebook, Twitter and/or a Web-log (“blog”). Larger volume clinics commonly host social networking websites. These sites provide new ways to communicate with patients, but clinics should maintain policies on the incorporation of social networks into practice. PMID:22088209

  2. The ART of social networking: how SART member clinics are connecting with patients online.

    Science.gov (United States)

    Omurtag, Kenan; Jimenez, Patricia T; Ratts, Valerie; Odem, Randall; Cooper, Amber R

    2012-01-01

    To study and describe the use of social networking websites among Society for Assisted Reproductive Technology (SART) member clinics. Cross-sectional study. University-based practice. Not applicable. Not applicable. Prevalence of social networking websites among SART member clinics and evaluation of content, volume, and location (i.e., mandated state, region) using multivariate regression analysis. A total of 384 SART-registered clinics and 1,382 social networking posts were evaluated. Of the clinics, 96% had a website and 30% linked to a social networking website. The majority of clinics (89%) with social networking websites were affiliated with nonacademic centers. Social networking posts mostly provided information (31%) and/or advertising (28%), and the remaining offered support (19%) or were irrelevant (17%) to the target audience. Only 5% of posts involved patients requesting information. Clinic volume correlated with the presence of a clinic website and a social networking website. Almost all SART member clinics have a website. Nearly one-third of these clinics host a social networking website such as Facebook, Twitter, and/or a blog. Large-volume clinics commonly host social networking websites. These sites provide new ways to communicate with patients, but clinics should maintain policies on the incorporation of social networks into practice. Copyright © 2012 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  3. Social networks and landscape of tourist destination: photos online in city image building

    Directory of Open Access Journals (Sweden)

    Luciana Noronha Pereira

    2017-12-01

    Full Text Available Tourist activity has the landscapes among its main attractions. Photographic records as fragments of reality are products of a look to aspects of the landscape and mediate the process of signification. New ways to record and share the tourist experience through produced digital photos and shared on-line has meant the expansion of this effect, and moreover has enabled new types of appropriation, interaction and so new forms of creation the space. This study aims to investigate possible influences of your online photos at image of tourist destinations, as from Balneário Camboriú (SC. The methodology includes a quantitative stage – quantity and location of the photos – and a qualitative – photos and comments submitted to the semiotic approach of content analysis. The concentration of on-line photos in seashore areas and the predominance of natural elements as central arguments, associated with positive emotions, stand out among the results.

  4. How social network analysis can be used to monitor online collaborative learning and guide an informed intervention

    Science.gov (United States)

    Fors, Uno; Tedre, Matti; Nouri, Jalal

    2018-01-01

    To ensure online collaborative learning meets the intended pedagogical goals (is actually collaborative and stimulates learning), mechanisms are needed for monitoring the efficiency of online collaboration. Various studies have indicated that social network analysis can be particularly effective in studying students’ interactions in online collaboration. However, research in education has only focused on the theoretical potential of using SNA, not on the actual benefits they achieved. This study investigated how social network analysis can be used to monitor online collaborative learning, find aspects in need of improvement, guide an informed intervention, and assess the efficacy of intervention using an experimental, observational repeated-measurement design in three courses over a full-term duration. Using a combination of SNA-based visual and quantitative analysis, we monitored three SNA constructs for each participant: the level of interactivity, the role, and position in information exchange, and the role played by each participant in the collaboration. On the group level, we monitored interactivity and group cohesion indicators. Our monitoring uncovered a non-collaborative teacher-centered pattern of interactions in the three studied courses as well as very few interactions among students, limited information exchange or negotiation, and very limited student networks dominated by the teacher. An intervention based on SNA-generated insights was designed. The intervention was structured into five actions: increasing awareness, promoting collaboration, improving the content, preparing teachers, and finally practicing with feedback. Evaluation of the intervention revealed that it has significantly enhanced student-student interactions and teacher-student interactions, as well as produced a collaborative pattern of interactions among most students and teachers. Since efficient and communicative activities are essential prerequisites for successful content

  5. Neural networks applied to speed cheating recognition in online computer games

    OpenAIRE

    Otavio Barcelos Gaspareto

    2008-01-01

    No presente trabalho, é testada e avaliada a aplicação de Redes Neurais Artificiais no combate de trapaças (cheating, em inglês) do tipo speed cheating em jogos online massivos de múltiplos jogadores, também conhecidos como MMOG (Massively Multi- player Online Games). Os MMOG representam um modelo de negócio onde quantias significativas de recursos financeiros estão envolvidas, e crescem a cada dia. Os mode- los para o combate de trapaças, que possam afastar jogadores de jogos ou servidores, ...

  6. Online social networks and resilient profile in university students with disabilities

    OpenAIRE

    Suriá, Raquel

    2015-01-01

    Desde hace algunos años, conocer si el uso de la redes sociales online está asociado a determinados perfiles de personalidad ha cobrado interés. Este puede ser el caso de algunas capacidades personales vinculadas a la competencia social como la resiliencia. El presente estudio examina si los jóvenes estudiantes con discapacidad que utilizan las redes sociales online tienen más desarrollada su capacidad resiliente. Participaron 96 estudiantes universitarios con diferentes tipos de discapacidad...

  7. [Violence in social networks: an exploration of the online expressions of teens from marginalized areas of Greater Buenos Aires].

    Science.gov (United States)

    Linne, Joaquín Walter; Angilletta, María Florencia

    2016-01-01

    This paper explores the online expressions of violence perpetrated or experienced by adolescents from marginalized areas of Greater Buenos Aires, Argentina. Using a qualitative methodology, four specific events were examined: threats, "bondis" [fights], cyberbullying and displays of mourning. To do so, 20 in-depth interviews and 3,000 virtual observations of profiles in the social network Facebook were carried out. Among the main results, it was seen that most expressions of violence are part of an offline-online dynamic. Empirical evidence is also offered based upon which it can be affirmed that the expressions of violence of these teenagers are developed around the culture of "aguante" [fierce loyalty]. The article ponders the extent to which, in the iconic platform of the option "like," these expressions are implicitly functional to the social network or, to the contrary, or whether they allow displacements and significant reappropriations on the part of users. New questions arise about the use of these tools by adolescents from marginalized areas and the need for more complex approaches to examine these phenomena.

  8. A fuzzy neural network model for monitoring A²/O process using on-line monitoring parameters.

    Science.gov (United States)

    Hu, Kang; Wan, Jin Q; Ma, Yong W; Wang, Yan; Huang, Ming Z

    2012-01-01

    An adaptive network based fuzzy inference system (ANFIS) model was employed to predict effluent chemical oxygen demand (COD(eff)) and ammonia nitrogen (NH(4)(+) (eff)) from an anaerobic/anoxic/oxic (A(2)/O) process, and meanwhile a self-adapted fuzzy c-means clustering algorithm was used to identify the model's architecture and optimize fuzzy rules. When constructing the model or predicting, the on-line monitoring parameters, namely hydraulic retention time (HRT), influent pH (pH), dissolved oxygen in the aerobic reactor (DO) and mixed-liquid return ratio (r), were adopted as the input variables. Compared with the artificial neural network (ANN) model whose weight vector was optimized by a real-code genetic algorithm (GA), the ANFIS presented better estimate performance. When predicting, the mean absolute percentage errors (MAPEs) of 1.8458% and 2.8984% for COD(eff) and NH(4)(+) (eff) could be achieved using ANFIS; the root mean square errors (RMSEs) for COD(eff) and NH(4)(+) (eff) were 1.6317 and 0.1291, respectively; the correlation coefficient (R) values of 0.9928 and 0.9951 for COD(eff) and NH(4)(+) (eff) could also be achieved. The results indicated that reasonable monitoring A(2)/O process performance, just using on-line monitoring parameters, has been achieved through the ANFIS.

  9. Improving Patient Involvement in the Drug Development Process: Case Study of Potential Applications from an Online Peer Support Network.

    Science.gov (United States)

    Anand, Amrutha; Brandwood, Helen Jane; Jameson Evans, Matt

    2017-11-01

    To date, social media has been used predominantly by the pharmaceutical industry to market products and to gather feedback and comments on products from consumers, a process termed social listening. However, social media has only been used cautiously in the drug development cycle, mainly because of regulations, restrictions on engagement with patients, or a lack of guidelines for social media use from regulatory bodies. Despite this cautious approach, there is a clear drive, from both the industry and consumers, for increased patient participation in various stages of the drug development process. The authors use the example of HealthUnlocked, one of the world's largest health networks, to illustrate the potential applications of online health communities as a means of increasing patient involvement at various stages of the drug development process. Having identified the willingness of the user population to be involved in research, numerous ways to engage users on the platform have been identified and explored. This commentary describes some of these approaches and reports how online health networks that encourage people to share their experiences in managing their health can, in turn, enable rapid patient engagement for clinical research within the constraints of industry regulation. Copyright © 2017 Elsevier HS Journals, Inc. All rights reserved.

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

    Science.gov (United States)

    Mannix, Judy; Wilkes, Lesley; Daly, John

    2014-01-01

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

  11. The persuasion context and results in online opinion seeking: effects of message and source-the moderating role of network managers.

    Science.gov (United States)

    Cabezudo, Rebeca San José; Izquierdo, Carmen Camarero; Pinto, Javier Rodríguez

    2013-11-01

    Online opinion networks are areas for social exchange, or conversational networks, made up of individuals actively involved in sharing experiences and opinions concerning matters of mutual interest between consumers or concerning their experience with a given product or service. We pinpoint a gap in the literature regarding how the persuasion process occurs when individuals seek opinions online, including the results process. In an attempt to find an answer, we draw on traditional theories related to information processing. These are mostly taken from the field of psychology and enable us to identify which signals or aspects of communication or opinions the individuals focus their attention on (message and source) and the value attached to such communications as well as how much they impact individuals' purchase decisions, bearing in mind the medium (or online opinion network) in which the opinions are located. Findings from those interviewed support the idea that the quality of information on the Internet, as well as trust in the source of said information, or in the opinion of network users, have an impact on the informational value obtained from involvement in this online opinion seeking and on purchasing decisions. Moreover, depending on the kind of network (firm or brand controlled, review Web sites, and user-controlled nonofficial opinion networks), the quality of the information or trust in the users will have a different bearing in the persuasion process.

  12. An online network tool for quality information to answer questions about occupational safety and health: usability and applicability

    Directory of Open Access Journals (Sweden)

    van Dijk Frank JH

    2010-10-01

    Full Text Available Abstract Background Common information facilities do not always provide the quality information needed to answer questions on health or health-related issues, such as Occupational Safety and Health (OSH matters. Barriers may be the accessibility, quantity and readability of information. Online Question & Answer (Q&A network tools, which link questioners directly to experts can overcome some of these barriers. When designing and testing online tools, assessing the usability and applicability is essential. Therefore, the purpose of this study is to assess the usability and applicability of a new online Q&A network tool for answers on OSH questions. Methods We applied a cross-sectional usability test design. Eight occupational health experts and twelve potential questioners from the working population (workers were purposively selected to include a variety of computer- and internet-experiences. During the test, participants were first observed while executing eight tasks that entailed important features of the tool. In addition, they were interviewed. Through task observations and interviews we assessed applicability, usability (effectiveness, efficiency and satisfaction and facilitators and barriers in use. Results Most features were usable, though several could be improved. Most tasks were executed effectively. Some tasks, for example searching stored questions in categories, were not executed efficiently and participants were less satisfied with the corresponding features. Participants' recommendations led to improvements. The tool was found mostly applicable for additional information, to observe new OSH trends and to improve contact between OSH experts and workers. Hosting and support by a trustworthy professional organization, effective implementation campaigns, timely answering and anonymity were seen as important use requirements. Conclusions This network tool is a promising new strategy for offering company workers high quality information

  13. 76 FR 7102 - Simplified Network Application Processing System, On-line Registration and Account Maintenance

    Science.gov (United States)

    2011-02-09

    ... the Chief Counsel for Advocacy of the Small Business Administration that the proposed rule, if adopted... Industry and Security (BIS) amends the Export Administration Regulations to implement a mandatory on-line... in their accounts current. This rulemaking is consistent with the goals and principles of Executive...

  14. Developing Online Learning Resources: Big Data, Social Networks, and Cloud Computing to Support Pervasive Knowledge

    Science.gov (United States)

    Anshari, Muhammad; Alas, Yabit; Guan, Lim Sei

    2016-01-01

    Utilizing online learning resources (OLR) from multi channels in learning activities promise extended benefits from traditional based learning-centred to a collaborative based learning-centred that emphasises pervasive learning anywhere and anytime. While compiling big data, cloud computing, and semantic web into OLR offer a broader spectrum of…

  15. Social Facilitation Effects by Pedagogical Conversational Agent: Lexical Network Analysis in an Online Explanation Task

    Science.gov (United States)

    Hayashi, Yugo

    2015-01-01

    The present study investigates web-based learning activities of undergraduate students who generate explanations about a key concept taught in a large-scale classroom. The present study used an online system with Pedagogical Conversational Agent (PCA), asked to explain about the key concept from different points and provided suggestions and…

  16. Online Data Monitoring Framework Based on Histogram Packaging in Network Distributed Data Acquisition Systems

    International Nuclear Information System (INIS)

    Konno, T; Ishitsuka, M; Kuze, M; Cabarera, A; Sakamoto, Y

    2011-01-01

    O nline monitor frameworkis a new general software framework for online data monitoring, which provides a way to collect information from online systems, including data acquisition, and displays them to shifters far from experimental sites. 'Monitor Server', a core system in this framework gathers the monitoring information from the online subsystems and the information is handled as collections of histograms named H istogram Package . Monitor Server broadcasts the histogram packages to 'Monitor Viewers', graphical user interfaces in the framework. We developed two types of the viewers with different technologies: Java and web browser. We adapted XML based file for the configuration of GUI components on the windows and graphical objects on the canvases. Monitor Viewer creates its GUIs automatically with the configuration files.This monitoring framework has been developed for the Double Chooz reactor neutrino oscillation experiment in France, but can be extended for general application to be used in other experiments. This document reports the structure of the online monitor framework with some examples from the adaption to the Double Chooz experiment.

  17. Teachers' Personal Learning Networks (PLNs): Exploring the Nature of Self-Initiated Professional Learning Online

    Science.gov (United States)

    Tour, Ekaterina

    2017-01-01

    In the field of Literacy Studies, online spaces have been recognised as providing many opportunities for spontaneous and self-initiated learning. While some progress has been made in understanding these important learning experiences, little attention has been paid to teachers' self-initiated professional learning. Contributing to the debates…

  18. A meta-analysis of social networking online and social capital

    NARCIS (Netherlands)

    Liu, Dong; Ainsworth, Sarah E.; Baumeister, Roy F.

    2016-01-01

    Social networking sites offer new avenues for interpersonal communication that may enable people to build social capital. The meta-analyses reported in this paper evaluated the relationship between social network site (SNS) use and 2 types of social capital: bridging social capital and bonding

  19. Detection of the inferred interaction network in hepatocellular carcinoma from EHCO (Encyclopedia of Hepatocellular Carcinoma genes Online).

    Science.gov (United States)

    Hsu, Chun-Nan; Lai, Jin-Mei; Liu, Chia-Hung; Tseng, Huei-Hun; Lin, Chih-Yun; Lin, Kuan-Ting; Yeh, Hsu-Hua; Sung, Ting-Yi; Hsu, Wen-Lian; Su, Li-Jen; Lee, Sheng-An; Chen, Chang-Han; Lee, Gen-Cher; Lee, D T; Shiue, Yow-Ling; Yeh, Chang-Wei; Chang, Chao-Hui; Kao, Cheng-Yan; Huang, Chi-Ying F

    2007-02-27

    The significant advances in microarray and proteomics analyses have resulted in an exponential increase in potential new targets and have promised to shed light on the identification of disease markers and cellular pathways. We aim to collect and decipher the HCC-related genes at the systems level. Here, we build an integrative platform, the Encyclopedia of Hepatocellular Carcinoma genes Online, dubbed EHCO http://ehco.iis.sinica.edu.tw, to systematically collect, organize and compare the pileup of unsorted HCC-related studies by using natural language processing and softbots. Among the eight gene set collections, ranging across PubMed, SAGE, microarray, and proteomics data, there are 2,906 genes in total; however, more than 77% genes are only included once, suggesting that tremendous efforts need to be exerted to characterize the relationship between HCC and these genes. Of these HCC inventories, protein binding represents the largest proportion (~25%) from Gene Ontology analysis. In fact, many differentially expressed gene sets in EHCO could form interaction networks (e.g. HBV-associated HCC network) by using available human protein-protein interaction datasets. To further highlight the potential new targets in the inferred network from EHCO, we combine comparative genomics and interactomics approaches to analyze 120 evolutionary conserved and overexpressed genes in HCC. 47 out of 120 queries can form a highly interactive network with 18 queries serving as hubs. This architectural map may represent the first step toward the attempt to decipher the hepatocarcinogenesis at the systems level. Targeting hubs and/or disruption of the network formation might reveal novel strategy for HCC treatment.

  20. Detection of the inferred interaction network in hepatocellular carcinoma from EHCO (Encyclopedia of Hepatocellular Carcinoma genes Online

    Directory of Open Access Journals (Sweden)

    Chen Chang-Han

    2007-02-01

    Full Text Available Abstract Background The significant advances in microarray and proteomics analyses have resulted in an exponential increase in potential new targets and have promised to shed light on the identification of disease markers and cellular pathways. We aim to collect and decipher the HCC-related genes at the systems level. Results Here, we build an integrative platform, the Encyclopedia of Hepatocellular Carcinoma genes Online, dubbed EHCO http://ehco.iis.sinica.edu.tw, to systematically collect, organize and compare the pileup of unsorted HCC-related studies by using natural language processing and softbots. Among the eight gene set collections, ranging across PubMed, SAGE, microarray, and proteomics data, there are 2,906 genes in total; however, more than 77% genes are only included once, suggesting that tremendous efforts need to be exerted to characterize the relationship between HCC and these genes. Of these HCC inventories, protein binding represents the largest proportion (~25% from Gene Ontology analysis. In fact, many differentially expressed gene sets in EHCO could form interaction networks (e.g. HBV-associated HCC network by using available human protein-protein interaction datasets. To further highlight the potential new targets in the inferred network from EHCO, we combine comparative genomics and interactomics approaches to analyze 120 evolutionary conserved and overexpressed genes in HCC. 47 out of 120 queries can form a highly interactive network with 18 queries serving as hubs. Conclusion This architectural map may represent the first step toward the attempt to decipher the hepatocarcinogenesis at the systems level. Targeting hubs and/or disruption of the network formation might reveal novel strategy for HCC treatment.

  1. The Web works in strange ways - unexpected results from MBARI's expanding use of online media and social networking

    Science.gov (United States)

    Fulton-bennett, K. W.

    2011-12-01

    As a relatively small organization, the Monterey Bay Aquarium Research Institute has gradually expanded its use of on-line and social media over the past few years. Our web site and expedition blogs have been available for over a decade. In 2009 we established a YouTube channel and RSS feeds. In early 2011 we set up Facebook and Twitter sites that are maintained through automated feeds (e.g. Twitterfeed) as well as by two employees who each spend about two hours a week adding items of interest. Although we do respond to comments, we have not actively encouraged interaction and discussion on our social networking sites, due to limited staff time. Prior to setting up our sites, I studied existing the Facebook pages for a number of marine research institutions and found that the frequency at which a research institution updated its social media site was directly correlated with the number of dedicated followers of that site. For this reason, MBARI set goals for keeping our sites updated on a regular basis-at least monthly for YouTube, and three to five times a week for Facebook and Twitter. While expanding our social media activities, we have also expanded our monitoring of all our on-line media. This monitoring has revealed some surprising findings. For example, although we have a steadily growing list of followers (over 1,000 "likes" on Facebook and almost 2,500 "subscribers" YouTube), the use of social media has not significantly increased traffic to our main institutional web site. For the last three years, this site has maintained fairly consistent traffic at 1,000 to 2,000 visits/day. We do see a few extreme spikes in traffic, which can be up to an order of magnitude above normal, when a major web site links to one of our news releases. Since initiating our social networking sites, we have seen an increase in these types of spikes, but it is too early to establish cause and effect in this case. Another unexpected finding is that we are reaching very different

  2. On-Line Detection of Distributed Attacks from Space-Time Network Flow Patterns

    National Research Council Canada - National Science Library

    Baras, J. S; Cardenas, A. A; Ramezani, V

    2003-01-01

    .... The directionality of the change in a network flow is assumed to have an objective or target. The particular problem of detecting distributed denial of service attacks from distributed observations is presented as a working framework...

  3. The value of online networks of practice: The role of embeddedness and media use

    NARCIS (Netherlands)

    van den Hooff, B.J.; de Leeuw van Weenen, F.; Soekijad, M.; Huysman, M.H.

    2010-01-01

    This article addresses the question how networks of practice (NoPs) can create value (operationalized as their contribution to individual members performance) for organizations through knowledge integration and management. The discussion focuses on two sets of variables influencing member

  4. Social networking, a new online addiction: a review of Facebook and other addiction disorders

    OpenAIRE

    Guedes, Eduardo; Nardi, Antonio Egidio; Guimarães, Flávia Melo Campos Leite; Machado, Sergio; King, Anna Lucia Spear

    2016-01-01

    INTRODUCTION: Facebook is the world's most widely accessed social network, where millions of people intercommunicate. Behavioral and psychological changes relate to abusive and uncontrolled use creating severe impacts on users' life. METHOD: A critical revision was performed through MedLine, Lilacs, SciELO and Cochrane databases using the terms: "Facebook Addiction," "Social Network Sites," "Facebook Abuse." The search covered the past 5 years up to January 2015. Articles that examine depend...

  5. Online Social Networking and Addiction—A Review of the Psychological Literature

    OpenAIRE

    Daria J. Kuss; Mark D. Griffiths

    2011-01-01

    Social Networking Sites (SNSs) are virtual communities where users can create individual public profiles, interact with real-life friends, and meet other people based on shared interests. They are seen as a ?global consumer phenomenon? with an exponential rise in usage within the last few years. Anecdotal case study evidence suggests that ?addiction? to social networks on the Internet may be a potential mental health problem for some users. However, the contemporary scientific literature addr...

  6. Object-Oriented Control System Design Using On-Line Training of Artificial Neural Networks

    Science.gov (United States)

    Rubaai, Ahmed

    1997-01-01

    This report deals with the object-oriented model development of a neuro-controller design for permanent magnet (PM) dc motor drives. The system under study is described as a collection of interacting objects. Each object module describes the object behaviors, called methods. The characteristics of the object are included in its variables. The knowledge of the object exists within its variables, and the performance is determined by its methods. This structure maps well to the real world objects that comprise the system being modeled. A dynamic learning architecture that possesses the capabilities of simultaneous on-line identification and control is incorporated to enforce constraints on connections and control the dynamics of the motor. The control action is implemented "on-line", in "real time" in such a way that the predicted trajectory follows a specified reference model. A design example of controlling a PM dc motor drive on-line shows the effectiveness of the design tool. This will therefore be very useful in aerospace applications. It is expected to provide an innovative and noval software model for the rocket engine numerical simulator executive.

  7. Online Social Networking and Addiction—A Review of the Psychological Literature

    Science.gov (United States)

    Kuss, Daria J.; Griffiths, Mark D.

    2011-01-01

    Social Networking Sites (SNSs) are virtual communities where users can create individual public profiles, interact with real-life friends, and meet other people based on shared interests. They are seen as a ‘global consumer phenomenon’ with an exponential rise in usage within the last few years. Anecdotal case study evidence suggests that ‘addiction’ to social networks on the Internet may be a potential mental health problem for some users. However, the contemporary scientific literature addressing the addictive qualities of social networks on the Internet is scarce. Therefore, this literature review is intended to provide empirical and conceptual insight into the emerging phenomenon of addiction to SNSs by: (1) outlining SNS usage patterns, (2) examining motivations for SNS usage, (3) examining personalities of SNS users, (4) examining negative consequences of SNS usage, (5) exploring potential SNS addiction, and (6) exploring SNS addiction specificity and comorbidity. The findings indicate that SNSs are predominantly used for social purposes, mostly related to the maintenance of established offline networks. Moreover, extraverts appear to use social networking sites for social enhancement, whereas introverts use it for social compensation, each of which appears to be related to greater usage, as does low conscientiousness and high narcissism. Negative correlates of SNS usage include the decrease in real life social community participation and academic achievement, as well as relationship problems, each of which may be indicative of potential addiction. PMID:22016701

  8. Online social networking and addiction--a review of the psychological literature.

    Science.gov (United States)

    Kuss, Daria J; Griffiths, Mark D

    2011-09-01

    Social Networking Sites (SNSs) are virtual communities where users can create individual public profiles, interact with real-life friends, and meet other people based on shared interests. They are seen as a 'global consumer phenomenon' with an exponential rise in usage within the last few years. Anecdotal case study evidence suggests that 'addiction' to social networks on the Internet may be a potential mental health problem for some users. However, the contemporary scientific literature addressing the addictive qualities of social networks on the Internet is scarce. Therefore, this literature review is intended to provide empirical and conceptual insight into the emerging phenomenon of addiction to SNSs by: (1) outlining SNS usage patterns, (2) examining motivations for SNS usage, (3) examining personalities of SNS users, (4) examining negative consequences of SNS usage, (5) exploring potential SNS addiction, and (6) exploring SNS addiction specificity and comorbidity. The findings indicate that SNSs are predominantly used for social purposes, mostly related to the maintenance of established offline networks. Moreover, extraverts appear to use social networking sites for social enhancement, whereas introverts use it for social compensation, each of which appears to be related to greater usage, as does low conscientiousness and high narcissism. Negative correlates of SNS usage include the decrease in real life social community participation and academic achievement, as well as relationship problems, each of which may be indicative of potential addiction.

  9. Online Social Networking and Addiction—A Review of the Psychological Literature

    Directory of Open Access Journals (Sweden)

    Daria J. Kuss

    2011-08-01

    Full Text Available Social Networking Sites (SNSs are virtual communities where users can create individual public profiles, interact with real-life friends, and meet other people based on shared interests. They are seen as a ‘global consumer phenomenon’ with an exponential rise in usage within the last few years. Anecdotal case study evidence suggests that ‘addiction’ to social networks on the Internet may be a potential mental health problem for some users. However, the contemporary scientific literature addressing the addictive qualities of social networks on the Internet is scarce. Therefore, this literature review is intended to provide empirical and conceptual insight into the emerging phenomenon of addiction to SNSs by: (1 outlining SNS usage patterns, (2 examining motivations for SNS usage, (3 examining personalities of SNS users, (4 examining negative consequences of SNS usage, (5 exploring potential SNS addiction, and (6 exploring SNS addiction specificity and comorbidity. The findings indicate that SNSs are predominantly used for social purposes, mostly related to the maintenance of established offline networks. Moreover, extraverts appear to use social networking sites for social enhancement, whereas introverts use it for social compensation, each of which appears to be related to greater usage, as does low conscientiousness and high narcissism. Negative correlates of SNS usage include the decrease in real life social community participation and academic achievement, as well as relationship problems, each of which may be indicative of potential addiction.

  10. The influence of the residency application process on the online social networking behavior of medical students: a single institutional study.

    Science.gov (United States)

    Strausburg, Matthew B; Djuricich, Alexander M; Carlos, W Graham; Bosslet, Gabriel T

    2013-11-01

    To evaluate medical students' behavior regarding online social networks (OSNs) in preparation for the residency matching process. The specific aims were to quantify the use of OSNs by students to determine whether and how these students were changing OSN profiles in preparation for the residency application process, and to determine attitudes toward residency directors using OSNs as a screening method to evaluate potential candidates. An e-mail survey was sent to 618 third- and fourth-year medical students at Indiana University School of Medicine over a three-week period in 2012. Statistical analysis was completed using nonparametric statistical tests. Of the 30.1% (183/608) who responded to the survey, 98.9% (181/183) of students reported using OSNs. More than half, or 60.1% (110/183), reported that they would (or did) alter their OSN profile before residency matching. Respondents' opinions regarding the appropriateness of OSN screening by residency directors were mixed; however, most respondents did not feel that their online OSN profiles should be used in the residency application process. The majority of respondents planned to (or did) alter their OSN profile in preparation for the residency match process. The majority believed that residency directors are screening OSN profiles during the matching process, although most did not believe their OSN profiles should be used in the residency application process. This study implies that the more medical students perceive that residency directors use social media in application screening processes, the more they will alter their online profiles to adapt to protect their professional persona.

  11. Manifestations of personality in Online Social Networks: self-reported Facebook-related behaviors and observable profile information.

    Science.gov (United States)

    Gosling, Samuel D; Augustine, Adam A; Vazire, Simine; Holtzman, Nicholas; Gaddis, Sam

    2011-09-01

    Despite the enormous popularity of Online Social Networking sites (OSNs; e.g., Facebook and Myspace), little research in psychology has been done on them. Two studies examining how personality is reflected in OSNs revealed several connections between the Big Five personality traits and self-reported Facebook-related behaviors and observable profile information. For example, extraversion predicted not only frequency of Facebook usage (Study 1), but also engagement in the site, with extraverts (vs. introverts) showing traces of higher levels of Facebook activity (Study 2). As in offline contexts, extraverts seek out virtual social engagement, which leaves behind a behavioral residue in the form of friends lists and picture postings. Results suggest that, rather than escaping from or compensating for their offline personality, OSN users appear to extend their offline personalities into the domains of OSNs.

  12. Self-presentation in Online Professional Networks: Men's Higher and Women's Lower Facial Prominence in Self-created Profile Images

    Science.gov (United States)

    Sczesny, Sabine; Kaufmann, Michèle C.

    2018-01-01

    Men are presented with higher facial prominence than women in the media, a phenomenon that is called face-ism. In naturalistic settings, face-ism effects could be driven by gender biases of photographers and/or by gender differences in self-presentation. The present research is the first to investigate whether women and men themselves create this different facial prominence. In a controlled laboratory study, 61 participants prepared a picture of themselves from a half-body photograph, allegedly to be uploaded to their profile for an online professional network. As expected, men cropped their photos with higher facial prominence than women did. However, women and men did not differ in the self-presentational motivations, goals, strategies, and personality variables under investigation, so that the observed face-ism effect could not be explained with these variables. Generally, the higher participants' physical appearance self-esteem, the higher was their self-created facial prominence. PMID:29387029

  13. Self-presentation in Online Professional Networks: Men's Higher and Women's Lower Facial Prominence in Self-created Profile Images.

    Science.gov (United States)

    Sczesny, Sabine; Kaufmann, Michèle C

    2017-01-01

    Men are presented with higher facial prominence than women in the media, a phenomenon that is called face-ism . In naturalistic settings, face-ism effects could be driven by gender biases of photographers and/or by gender differences in self-presentation. The present research is the first to investigate whether women and men themselves create this different facial prominence. In a controlled laboratory study, 61 participants prepared a picture of themselves from a half-body photograph, allegedly to be uploaded to their profile for an online professional network. As expected, men cropped their photos with higher facial prominence than women did. However, women and men did not differ in the self-presentational motivations, goals, strategies, and personality variables under investigation, so that the observed face-ism effect could not be explained with these variables. Generally, the higher participants' physical appearance self-esteem, the higher was their self-created facial prominence.

  14. Self-presentation in Online Professional Networks: Men's Higher and Women's Lower Facial Prominence in Self-created Profile Images

    Directory of Open Access Journals (Sweden)

    Sabine Sczesny

    2018-01-01

    Full Text Available Men are presented with higher facial prominence than women in the media, a phenomenon that is called face-ism. In naturalistic settings, face-ism effects could be driven by gender biases of photographers and/or by gender differences in self-presentation. The present research is the first to investigate whether women and men themselves create this different facial prominence. In a controlled laboratory study, 61 participants prepared a picture of themselves from a half-body photograph, allegedly to be uploaded to their profile for an online professional network. As expected, men cropped their photos with higher facial prominence than women did. However, women and men did not differ in the self-presentational motivations, goals, strategies, and personality variables under investigation, so that the observed face-ism effect could not be explained with these variables. Generally, the higher participants' physical appearance self-esteem, the higher was their self-created facial prominence.

  15. Using Social Media, Online Social Networks, and Internet Search as Platforms for Public Health Interventions: A Pilot Study.

    Science.gov (United States)

    Huesch, Marco D; Galstyan, Aram; Ong, Michael K; Doctor, Jason N

    2016-06-01

    To pilot public health interventions at women potentially interested in maternity care via campaigns on social media (Twitter), social networks (Facebook), and online search engines (Google Search). Primary data from Twitter, Facebook, and Google Search on users of these platforms in Los Angeles between March and July 2014. Observational study measuring the responses of targeted users of Twitter, Facebook, and Google Search exposed to our sponsored messages soliciting them to start an engagement process by clicking through to a study website containing information on maternity care quality information for the Los Angeles market. Campaigns reached a little more than 140,000 consumers each day across the three platforms, with a little more than 400 engagements each day. Facebook and Google search had broader reach, better engagement rates, and lower costs than Twitter. Costs to reach 1,000 targeted users were approximately in the same range as less well-targeted radio and TV advertisements, while initial engagements-a user clicking through an advertisement-cost less than $1 each. Our results suggest that commercially available online advertising platforms in wide use by other industries could play a role in targeted public health interventions. © Health Research and Educational Trust.

  16. On Predicting Sociodemographic Traits and Emotions from Communications in Social Networks and Their Implications to Online Self-Disclosure.

    Science.gov (United States)

    Volkova, Svitlana; Bachrach, Yoram

    2015-12-01

    Social media services such as Twitter and Facebook are virtual environments where people express their thoughts, emotions, and opinions and where they reveal themselves to their peers. We analyze a sample of 123,000 Twitter users and 25 million of their tweets to investigate the relation between the opinions and emotions that users express and their predicted psychodemographic traits. We show that the emotions that we express on online social networks reveal deep insights about ourselves. Our methodology is based on building machine learning models for inferring coarse-grained emotions and psychodemographic profiles from user-generated content. We examine several user attributes, including gender, income, political views, age, education, optimism, and life satisfaction. We correlate these predicted demographics with the emotional profiles emanating from user tweets, as captured by Ekman's emotion classification. We find that some users tend to express significantly more joy and significantly less sadness in their tweets, such as those predicted to be in a relationship, with children, or with a higher than average annual income or educational level. Users predicted to be women tend to be more opinionated, whereas those predicted to be men tend to be more neutral. Finally, users predicted to be younger and liberal tend to project more negative opinions and emotions. We discuss the implications of our findings to online privacy concerns and self-disclosure behavior.

  17. A neural network methodology for traffic congestion prediction and online traffic control

    Energy Technology Data Exchange (ETDEWEB)

    Demmou, H.; Hermitte, L.; Sahraoui, A. [Centre National de la Recherche Scientifique (CNRS), 31 - Toulouse (France). Laboratoire d`Analyse et d`Architecture des Systemes; Olivero, P. [ZELT, 31 - Toulouse (France)

    1998-12-01

    The aim of this paper is to present an approach for traffic light signals control and traffic congestion prediction based on the neural network technique. We propose to define and implement a modular and integrated functional structure to realize these two very important tasks when facing traffic problems. A methodology for Neural Network approach is proposed. The approach is intended for transportation systems and mainly for urban traffic control. The main objectives of the work are two fold; the first is to develop a generic methodology for Neural Network approach; the second is to enhance such development for transportation issues mainly in urban traffic congestion detection, congestion prediction, supervision and control. (authors) 5 refs.

  18. Social networking online to recover from opioid use disorder: A study of community interactions.

    Science.gov (United States)

    D'Agostino, Alexandra R; Optican, Allison R; Sowles, Shaina J; Krauss, Melissa J; Escobar Lee, Kiriam; Cavazos-Rehg, Patricia A

    2017-12-01

    Social media has increasingly become a venue for health discourse and support, particularly for vulnerable individuals. This study examines user-generated content of an online Reddit community targeting individuals recovering from opiate addiction. 100 Reddit posts and their comments were collected from the online community on August 19, 2016. Posts were qualitatively coded for opioid use disorder (OUD) criteria as outlined by the Diagnostic and Statistical Manual of Mental Disorders (DSM-5), as well as other common themes. Comments were coded for expression of distinct therapeutic factors (i.e., instillation of hope, universality, imparting information, and altruism). All posts and comments were coded for addiction phase of the author (i.e., using, withdrawing, recovering). 73 unique usernames authored the 100 posts. Among the 73 usernames, 33% (24/73) described enough symptoms in their posts to meet DSM-V criteria for OUD (16/73 or 22% mild severity, 7/73 or 10% moderate severity, and 1/73 or 1% high severity. Among the 100 posts, advice was requested in 43% (43/100) of the posts and support was sought in 24% (24/100) of the posts. There were 511 comments made on the 100 posts, nearly all of which contained at least one distinct therapeutic factor (486/511, 95%) with altruism being the most common (341/511, 67%). This research provides validity to the supportive content generated on an online recovery-oriented community, while also revealing discussions of self-reported struggles with OUD among group members. Future research should explore the feasibility of incorporating social media-based peer support into traditional addiction treatments. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Development of an online tool for public health: the European Public Health Law Network.

    Science.gov (United States)

    Basak, P

    2011-09-01

    The European Public Health Law Network was established in 2007 as part of the European Union (EU) co-funded Public Health Law Flu project. The aims of the website consisted of designing an interactive network of specialist information and encouraging an exchange of expertise amongst members. The website sought to appeal to academics, public health professionals and lawyers. The Public Health Law Flu project team designed and managed the website. Registered network members were recruited through publicity, advertising and word of mouth. Details of the network were sent to health organizations and universities throughout Europe. Corresponding website links attracted many new visitors. Publications, news, events and a pandemic glossary became popular features on the site. Although the website initially focused only on pandemic diseases it has grown into a multidisciplinary website covering a range of public health law topics. The network contains over 700 publications divided into 28 public health law categories. News, events, front page content, legislation and the francophone section are updated on a regular basis. Since 2007 the website has received over 15,000 views from 156 countries. Newsletter subscribers have risen to 304. There are now 723 followers on the associated Twitter site. The European Public Health Law Network has been a successful and innovative site in the area of public health law. Interest in the site continues to grow. Future funding can contribute to a bigger site with interactive features and pages in a wider variety of languages to attract a wider global audience. Copyright © 2011 The Royal Society for Public Health. Published by Elsevier Ltd. All rights reserved.

  20. Young People's Use of Online Social Networking Sites :a Uses and Gratifications Perspective

    OpenAIRE

    Dunne, Aine; Lawlor, Margaret-Anne; Rowley, Jennifer

    2010-01-01

    Abstract Purpose – The purpose of this paper is to explore why young people use and participate in social networking sites (SNS) with specific reference to Bebo. Design/methodology/approach – A qualitative approach is employed in this study with a view to exploring the uses and gratifications that girls aged 12 to 14 years, both seek and obtain from the Bebo social networking site. The research was conducted in a school setting in Ireland. Findings – The findings indicate that the participant...