691 research outputs found

    Contextualizing the blogosphere: A comparison of traditional and novel user interfaces for the web

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    In this paper, we investigate how contextual user interfaces affect blog reading experience. Based on a review of previous research, we argue why and how contextualization may result in (H1) enhanced blog reading experiences. In an eyetracking experiment, we tested 3 different web-based user interfaces for information spaces. The StarTree interface (by Inxight) and the Focus-Metaphor interface are compared with a standard blog interface. Information tasks have been used to evaluate and compare task performance and user satisfaction between these three interfaces. We found that both contextual user interfaces clearly outperformed the traditional blog interface, both in terms of task performance as well as user satisfaction. © 2007 Laqua, S., Ogbechie, N. and Sasse, M. A

    Why do people use unsecure public Wi-Fi? An investigation of behaviour and factors driving decisions

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    © 2016 Copyright is held by the owner/author(s). Public Wi-Fi networks are now widely available in many countries. Though undoubtedly convenient, such networks have potential security and privacy risks. The aim of this study was to understand if people are aware of those risks, and - if so - why they decide to take them. We set up an experimental free Wi-Fi network at 14 locations in central London, UK, for a period of 150 hours, and people connected most often to use instant messaging, search engines, and social networks, and sensitive data (such as name, date of birth, and sexual orientation) were transmitted. We subsequently investigated people's risk awareness and risk behaviour through semi-structured interviews with 14 participants, and an online scenario-based survey with 102 participants. The majority of participants said they would use public Wi-Fi under circumstances where the risks taken are not consistent with maximising utility. Female participants rated the risks associated with public Wi-Fi use, more highly - and yet more females than males said they would use them to save their data plans. These findings align with insights from behavioural economics, specifically the insight that people can misjudge risky situations and do not make decisions consistent with expected utility theory

    Transmission of primary resistance mutation K103N in a cluster of Belgian young patients from different risk groups

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    Background: We analysed the distribution of an HIV-1 subtype B strain resistant to efavirenz and nevirapine among incident infections in the Belgian population. Method: The Belgian AIDS reference laboratories searched their databases for HIV-1 subtype B sequences harbouring the K103N mutation in the reverse transcriptase (RT) or the C67S and V77I mutations in the protease (PR). We included the earliest RT sequence available of drug-naĂŻve patients as well as sequences related to treatment failure. Fifty sequences were aligned omitting the codon 103 and submitted to phylogenetic analysis. Epidemiological data were collected through the Institute of Public Health national database. In addition, three sequences from the cluster were analysed by deep sequencing using the Roche GS Junior platform. Results: Phylogenetic analysis revealed the presence of a 24 virus sequences cluster. All except one of those sequences resulted from patients who were ARV-naĂŻve at the time of sampling, and 21 had the K103N mutation. Two thirds of the clustered patients were infected through homosexual or bisexual contacts while the others were heterosexuals. No case was related to migrants contaminated abroad. Fifteen of the clustered patients were diagnosed between January 2011 and June 2012; 87% of them were aged between 20 and 29 at the time of diagnosis. Interestingly, 60% of them reside in the province of Namur. Deep sequencing analysis of 3 individuals sampled near seroconversion revealed no other resistance mutations at a frequency > 1% than those already picked up by Sanger sequencing (RT A98S, K103N; PR V77I), except the RT V90I. Conclusion: We identified a transmission cluster of drug resistant HIV-1 variants mainly including homo- and heterosexual young adults. Most individuals are of Belgian origin and are living around the city of Namur (Belgium). The K103N mutation had no apparent impact on transmission fitness as its spread raised during the last years. These observations may impact on local prevention and ARV prophylaxis strategies

    Why trust seals don't work: a study of user perceptions and behavior.

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    Trust seals, such as the VeriSign and TRUSTe logos, are widely used to indicate a website is reputable. But how much protection do they offer to online shoppers? We conducted a study in which 60 experienced online shop-pers rated 6 websites – with and without trust seals - based on how trustworthy they perceived them to be. Eye track-ing data reveals that 38% of participants failed to notice any of the trust seals present. When seals were noticed, the ratings assigned to each website were significantly higher than for the same website without a seal, but qualitative analysis of the interview data revealed significant misconceptions of their meaning (e.g. “presence of seals automati-cally legitimizes any website”). Participants tended to rely on self-developed – but inaccurate – heuristics for as-sessing trustworthiness (e.g. perceived investment in website development, or references to other recognizable enti-ties). We conclude that current trust seals currently do not offer effective protection against scam websites; and sug-gest that other mechanisms – such as automatic verification of authenticity are required to support consumers’ trust decisions

    A neural network-based estimate of the seasonal to inter-annual variability of the Atlantic Ocean carbon sink

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    The Atlantic Ocean is one of the most important sinks for atmospheric carbon dioxide (CO2), but this sink has been shown to vary substantially in time. Here we use surface ocean CO2 observations to estimate this sink and the temporal variability from 1998 through 2007 in the Atlantic Ocean. We benefit from (i) a continuous improvement of the observations, i.e. the Surface Ocean CO2 Atlas (SOCAT) v1.5 database and (ii) a newly developed technique to interpolate the observations in space and time. In particular, we use a two-step neural network approach to reconstruct basin-wide monthly maps of the sea surface partial pressure of CO2 (pCO2) at a resolution of 1° × 1°. From those, we compute the air–sea CO2 flux maps using a standard gas exchange parameterization and high-resolution wind speeds. The neural networks fit the observed pCO2 data with a root mean square error (RMSE) of about 10 ÎŒatm and with almost no bias. A check against independent time-series data and new data from SOCAT v2 reveals a larger RMSE of 22.8 ÎŒatm for the entire Atlantic Ocean, which decreases to 16.3 ÎŒatm for data south of 40° N. We estimate a decadal mean uptake flux of −0.45 ± 0.15 Pg C yr−1 for the Atlantic between 44° S and 79° N, representing the sum of a strong uptake north of 18° N (−0.39 ± 0.10 Pg C yr−1), outgassing in the tropics (18° S–18° N, 0.11 ± 0.07 Pg C yr−1), and uptake in the subtropical/temperate South Atlantic south of 18° S (−0.16 ± 0.06 Pg C yr−1), consistent with recent studies. The strongest seasonal variability of the CO2 flux occurs in the temperature-driven subtropical North Atlantic, with uptake in winter and outgassing in summer. The seasonal cycle is antiphased in the subpolar latitudes relative to the subtropics largely as a result of the biologically driven winter-to-summer drawdown of CO2. Over the 10 yr analysis period (1998 through 2007), sea surface pCO2 increased faster than that of the atmosphere in large areas poleward of 40° N, while in other regions of the North Atlantic the sea surface pCO2 increased at a slower rate, resulting in a barely changing Atlantic carbon sink north of the Equator (−0.01 ± 0.02 Pg C yr−1 decade−1). Surface ocean pCO2 increased at a slower rate relative to atmospheric CO2 over most of the Atlantic south of the Equator, leading to a substantial trend toward a stronger CO2 sink for the entire South Atlantic (−0.14 ± 0.02 Pg C yr−1 decade−1). In contrast to the 10 yr trends, the Atlantic Ocean carbon sink varies relatively little on inter-annual timescales (±0.04 Pg C yr−1; 1 σ)

    Are Payment Card Contracts Unfair?

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    Fraud victims are often refused a refund by their bank on the grounds that they failed to comply with their bank’s terms and conditions about PIN safety. We, therefore, conducted a survey of how many PINs people have, and how they manage them. We found that while only a third of PINs are ever changed, almost half of bank customers write at least one PIN down. We also found bank conditions that are too vague to test, or even contradictory on whether PINs could be shared across cards. Yet, some rather hazardous practices are not forbidden at all by many banks: of the 22.9% who re-use PINs across devices, half also use their bank PINs on their mobile phones. We conclude that many bank contracts fail a simple test of reasonableness, and that ‘strong authentication’, as required by PSD II, should include usability testing

    Make mine a quadruple: Strengthening the security of graphical one-time PIN authentication

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    Secure and reliable authentication is an essential prerequisite for many online systems, yet achieving this in a way which is acceptable to customers remains a challenge. GrIDsure, a one-time PIN scheme using random grids and personal patterns, has been proposed as a way to overcome some of these challenges. We present an analytical study which demonstrates that GrIDsure in its current form is vulnerable to interception. To strengthen the scheme, we propose a way to fortify GrIDsure against Man-in-the-Middle attacks through (i) an additional secret transmitted out-of-band and (ii) multiple patterns. Since the need to recall multiple patterns increases user workload, we evaluated user performance with multiple captures with 26 participants making 15 authentication attempts each over a 3-week period. In contrast with other research into the use of multiple graphical passwords, we find no significant difference in the usability of GrIDsure with single and with multiple patterns. © 2011 IEEE

    Data-based estimates of the ocean carbon sink variability – First results of the Surface Ocean pCO2 Mapping intercomparison (SOCOM)

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    Using measurements of the surface-ocean CO2 partial pressure (pCO2) and 14 different pCO2 mapping methods recently collated by the Surface Ocean pCO2 Mapping intercomparison (SOCOM) initiative, variations in regional and global sea–air CO2 fluxes are investigated. Though the available mapping methods use widely different approaches, we find relatively consistent estimates of regional pCO2 seasonality, in line with previous estimates. In terms of interannual variability (IAV), all mapping methods estimate the largest variations to occur in the eastern equatorial Pacific. Despite considerable spread in the detailed variations, mapping methods that fit the data more closely also tend to agree more closely with each other in regional averages. Encouragingly, this includes mapping methods belonging to complementary types – taking variability either directly from the pCO2 data or indirectly from driver data via regression. From a weighted ensemble average, we find an IAV amplitude of the global sea–air CO2 flux of 0.31 PgC yr−1 (standard deviation over 1992–2009), which is larger than simulated by biogeochemical process models. From a decadal perspective, the global ocean CO2 uptake is estimated to have gradually increased since about 2000, with little decadal change prior to that. The weighted mean net global ocean CO2 sink estimated by the SOCOM ensemble is −1.75 PgC yr−1 (1992–2009), consistent within uncertainties with estimates from ocean-interior carbon data or atmospheric oxygen trend

    The continued risks of unsecured public Wi-Fi and why users keep using it: Evidence from Japan

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    Many people find public Wi-Fi networks convenient but these networks harbor security and privacy risks. As public knowledge of these risks becoming common, we investigated whether the risks were still at large and what factors influenced users to use the networks — being the first study to draw evidence from Japan. Adapting the methodology from a previous study in the UK, we first set up an experimental open public Wi-Fi network at 11 locations in downtown Nara and captured Internet traffic. From approximately 7.7 million packets captured from 196 unique mobile devices during a 150-hour experiment, we found private photos, emails, documents, and login credentials being transmitted in clear text without encryption — confirming that not only did many applications still fail to encrypt data-inmotion but also did many users continue to use unsecured public Wi-Fi networks. We then used a scenario-based survey to examine factors affecting the users’ decision to use the networks. From 103 participants, we found that the desire to conserve mobile data — a form of resource preservation heuristic — instigated a risk-taking attitude and influenced participants, especially among those usually having a small monthly data plan, to use unsecured public Wi-Fi networks. Female and those having finish highschool only, were also more likely to use the networks
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