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Temporal node centrality in complex networks.
A simple but powerful model, the time-ordered graph, is presented, which reduces a dynamic network to a static network with directed flows, which enables it to extend network properties such as vertex degree, closeness, and betweenness centrality metrics in a very natural way to the dynamic case. Expand
On the Effectiveness of Pattern Lock Strength Meters: Measuring the Strength of Real World Pattern Locks
The statistical analysis indicates that about 10% of the pattern locks that were generated without the meter support could be compromised through just 16 guessing attempts, showing significant improvement in security. Expand
An image encryption scheme with a pseudorandom permutation based on chaotic maps
Many research efforts for image encryption schemes have elaborated for designing nonlinear functions since security of these schemes closely depends on inherent characteristics of nonlinearExpand
What's in Your Tweets? I Know Who You Supported in the UK 2010 General Election
The experimental results showed that the best-performing classification method - which uses the number of Twitter messages referring to a particular political party - achieved about 86% classification accuracy without any training phase. Expand
Hybrid spam filtering for mobile communication
The trade-off between the accuracy of anti-spam classifiers and the incurring traffic overhead is shown, and it is demonstrated that the hybrid framework is capable of achieving high accuracy regardless of the content-based filtering algorithm being used. Expand
Bitcoin vs. Bitcoin Cash: Coexistence or Downfall of Bitcoin Cash?
A coin can intentionally weaken the security and decentralization level of the other rival coin when mining hardware is shared between them, allowing for automatic mining. Expand
SysPal: System-Guided Pattern Locks for Android
This work proposes a novel system-guided pattern lock scheme called "SysPal" that mandates the use of a small number of randomly selected points while selecting a pattern, and suggests that the two SysPal policies can help users select significantly more secure patterns compared to the current Android policy. Expand
Social Authentication: Harder Than It Looks
A number of web service firms have started to authenticate users via their social knowledge, such as whether they can identify friends from photos. We investigate attacks on such schemes. First,Expand
I Don't Use Apple Pay Because It's Less Secure ...: Perception of Security and Usability in Mobile Tap-and-Pay
This paper reports on why people use, not use, or have stopped using mobile tap-and-pay in stores. The results of our online survey with 349 Apple Pay and 511 Android Pay participants suggest thatExpand
What’s in Twitter, I know what parties are popular and who you are supporting now!
An incremental and practical classification method which uses the number of Twitter messages referring to a particular political party or retweets, and a classifier leveraging the valuable semantic content of the List feature to estimate the overall political leaning of users is developed. Expand