Abstract

Abstract

Abstract

Abstract
Attribute grammars are a powerfull, well-known formalism to implement and reason about programs which, by design, are conveniently modular. In this work we focus on a state of the art zipper-based embedding of classic attribute grammars and higher-order attribute grammars. We improve their execution performance through controlling attribute (re)evaluation by means of memoization techniques. We present the results of our optimizations by comparing their impact in various implementations of different, well-studied, attribute grammars and their Higher-Order extensions. © 2018 Elsevier B.V.

Abstract
Alloy supports reasoning about software designs in early development stages. It is composed of a modelling language and a tool that is able to find valid instances of the model. Alloy is able to produce graphical representations of analysis results, which is essential for their interpretation. In previous work we have improved the representations with the usage of layout managers. Here, we further extend that work by presenting the improvements on the approach, and by introducing a new case study to analyse the contribution of layout managers, and to support validation trough a user study. © 2018 IEEE.

Abstract
We construct functional encryption (FE) schemes for the orthogonality (OFE) relation where each ciphertext encrypts some vector (Formula Presented) and each decryption key, associated to some vector (Formula Presented), allows to determine if (Formula Presented) is orthogonal to (Formula Presented) or not. Motivated by compelling applications, we aim at schemes which are function hidding, i.e. (Formula Presented) is not leaked. Our main contribution are two such schemes, both rooted in existing constructions of FE for inner products (IPFE), i.e., where decryption keys reveal the inner product of (Formula Presented) and (Formula Presented). The first construction builds upon the very efficient IPFE by Kim et al. (SCN 2018) but just like the original scheme its security holds in the generic group model (GGM). The second scheme builds on recent developments in the construction of efficient IPFE schemes in the standard model and extends the work of Wee (TCC 2017) in leveraging these results for the construction of FE for Boolean functions. Conceptually, both our constructions can be seen as further evidence that shutting down leakage from inner product values to only a single bit for the orthogonality relation can be done with little overhead, not only in the GGM, but also in the standard model. We discuss potential applications of our constructions to secure databases and provide efficiency benchmarks. Our implementation shows that the first scheme is extremely fast and ready to be deployed in practical applications. © 2019, Springer Nature Switzerland AG.