The structure of the Semantic Web gives users the power to share and collaboratively generate decentralized linked data. In many cases, though, collaboration requires some form of authentication and authorization to ensure the security and integrity of the data being generated. Traditional authorization systems that rely on centralized databases are insufficient in this scenario, since they rel...

A selective disclosure attribute-based credential system (SDABCS) can provide a communication mechanism to protect both security and privacy in electronic communication, by issuing a kind of credential with attributes, which the user can disclose parts of attributes. We present a general framework for formally verification of SDABCS with applied Pi calculus, and provide three definitions of rel...

We describe a practical attack on the High Bandwidth Digital Content Protection (HDCP) scheme. HDCP is a proposed identity-based cryptosystem for use over the Digital Visual Interface bus, a consumer video bus used in digital VCRs, camcorders, and personal computers. Public/private key pairs are assigned to devices by a trusted authority, which possesses a master secret. If an attacker can reco...

This paper introduces Hidden Identity-based Signatures (Hidden-IBS), a type of digital signatures that provide mediated signer-anonymity on top of Shamir’s Identity-based signatures. The motivation of our new signature primitive is to resolve an important issue with the kind of anonymity offered by “group signatures” where it is required that either the group membership list is public or that t...

Instagram has more than 400 million monthly active accounts who share more than 80 million pictures and videos daily. This large volume of user-generated content is the application’s notable strength, but also makes the problem of finding the authoritative users for a given topic challenging. Discovering topical authorities can be useful for providing relevant recommendations to the users. In a...

Diabetes is the third commonest chronic illness in children following asthma and epilepsy. More recently the overall prevalence of diabetes in children and adults continued to increase dramatically. In children, this has partially been contributed to by the pandemic of obesity. Understandably, this posed an economic burden on health authorities and countries dealing with significant morbidity o...

The hospital case notes of 209 (98%) of the 213 patients placed on an adult ophthalmic surgical waiting list between mid 1984 and mid 1985 were reviewed. Information on referral sources, previous eye surgery, outpatient visits, and treatment up to the end of 1987 was recorded. The vital status of patients up to the end of 1988 was also ascertained. Waiting list patients (123 women, 86 men) were...