Differential privacy is a notion of privacy that has become very popular in the database community. Roughly, the idea is that a randomized query mechanism provides sufficient privacy protection if the ratio between the probabilities that two adjacent datasets give the same answer is bound by eǫ. In the field of information flow there is a similar concern for controlling information leakage, i.e...

Protecting data is not simply a case of encrypt and forget: even data with full cryptographic confidentiality and integrity protection can still be subject to information leakage. We consider the issue of information leakage through side channels in protocols. Previous work by Bond and Clulow identified multiple vulnerabilities in APIs for financial PIN processing systems, and suggested remedie...

Security-typed languages can be used to build programs that are information-flow secure, meaning that they do not allow secret data to leak. Declassification allows programs to leak secret information in carefully prescribed ways. Manually placing declassifiers to authorize certain flows of information can be dangerous because an incorrectly placed declassifier can leak far more secure data tha...

We consider the problem of defining the information leakage in interactive systems where secrets and observables can alternate during the computation. We show that the information-theoretic approach which interprets such systems as (simple) noisy channels is not valid anymore. However, the principle can be recovered if we consider more complicated types of channels, that in Information Theory a...

In the inference attacks studied in Quantitative Information Flow (QIF), the attacker typically tries to interfere with the system in the attempt to increase its leakage of secret information. The defender, on the other hand, typically tries to decrease leakage by introducing some controlled noise. This noise introduction can be modeled as a type of protocol composition, i.e., a probabilistic c...

A variant of Mobile Ambient Calculus is introduced, called Boundary Ambient, to model multilevel security policies. Ambients that may guarantee to properly protect their content are explicitly identified as boundaries: a boundary can be seen as a resource access manager for confidential data. In this setting, we define a notion of non-interference which captures the absence of any (both direct ...

The effect of the blade tip geometry of a high pressure gas turbine is studied experimentally and computationally for high speed leakage flows. For this purpose two simplified models are constructed, one models a flat tip of the blade and the second models a cavity tip of the blade. Experimental results are obtained from a transonic wind tunnel to show the static pressure distribution along the...

Certification tests currently employed by some industrialized nations to certify respirators require that when challenged with air flow at a constant suction head of 25 mmH2O, the leakage into the facepiece from the exhalation valve(s) should not exceed 30 ml min(-1). However, the test alone might not reflect the leakage rate under different levels of vacuum. To study the characteristics of lea...

Static power consumption is nowadays a crucial design parameter in digital circuits due to emergent mobile products. Leakage currents, the main responsible for static power dissipation during idle mode, are increasing dramatically in sub-100nm processes. Subthershold leakage rises due to threshold voltage scaling while gate leakage current increases due to scaling of oxide thickness. It means t...

In this study we have used a convergent and highly accurate mixed finite element technique to model the effect of fluid elasticity on the flow kinematics and the stress distribution in lid driven cavity flow. Our work is motivated by the desire to capture the important physical aspects of the basic flow and thus to better understand the purely elastic instability in recirculating flows which ha...