A valid compiler optimisation transforms a block in a program without introducing new observable behaviours to the program as a whole. Deciding which optimisations are valid can be difficult, and depends closely on the semantic model of the programming language. Axiomatic relaxed models, such as C++11, present particular challenges for determining validity, because such models allow subtle effe...

Recent work has sparked new interest in type-supervised part-of-speech tagging, a data setting in which no labeled sentences are available, but the set of allowed tags is known for each word type. This paper describes observational initialization, a novel technique for initializing EM when training a type-supervised HMM tagger. Our initializer allocates probability mass to unambiguous transitio...

Generic programming (GP) is an increasingly important trend in programming languages. Well-known GP mechanisms, such as type classes and the C++0x concepts proposal, usually combine two features: 1) a special type of interfaces; and 2) implicit instantiation of implementations of those interfaces. Scala implicits are a GP language mechanism, inspired by type classes, that break with the traditi...

This paper summarises the main outcomes of the Mobile Resource Guarantees (MRG) project, which focused on a proof-carrying-code (PCC) infrastructure for resources to be applied to mobile code. MRG was a three year project funded by the EC under the FET proactive initiative on Global Computing. We give an overview of the projects’ results, discuss the lessons learnt from it and introduce follow-...

In the current phase of the IPv6 transition, it is a typical situation that IPv6-only clients should be enabled to communicate with IPv4-only servers. The DNS64+NAT64 tool suite is an excellent solution to this problem. Although several free software DNS64 implementations exist, we point out that there is room for further high performance and computation efficient multithreaded DNS64 implementa...

2 Radiotracers ......................................................................... 16 2.1 11C-Choline, 18F-Choline .................................................... 16 2.2 11C-Acetate ........................................................................... 16 2.3 18F-Fluorodeoxyglucose (FDG) ........................................... 17 2.4 18F-Fluoride ...............................

A library for the emulation of C++0x concepts developed using the emerging C++11 programming language is presented. The library integrates existing techniques for concept checking and template metaprogramming to provide a uniform interface to defining and using concepts. The purpose of this work is to establishing a concrete foundation for experimentation of design techniques for concepts and t...