There are four large next-generation tokamak devices presently being designed. These are:(1) the JET (Joint European Torus) project sponsored by the Commission of the European Communities in association with EURATOM, (2) the TCT (Two-Component Torus) project underway in the United States of America, (3) the JT-60 (Japan-Tokamak) project of Japan and the T-20 tokamak project of the Union of Soviet Socialist Republics. The meeting held in Dubna provided an opportunity for leading members of the various projects to discuss the scientific objectives and detailed design features of each device, with the hope that an informal exchange of information on what each team was trying to do and how it was going about it could lead to some useful co-ordination of effort and avoidance of duplicate effort. The timing of the meeting was such that any resulting design modifications could yet be incorporated into present designs, even in the most advanced of the projects.The first two days of the meeting were devoted to detailed descriptions of the major characteristics of each machine and its sub-systems, and the reasons for the design approaches adopted. A brief summary of the four projects is given below, as prepared by B. B. Kadomtsev, General Chairman of the conference. Included is a table giving a combined list of design parameters. More detailed descriptions of the four tokamak projects are given in Annexes I, II, III and IV.Four days of the meeting were given over to workshop-type sessions on various component systems and selected problem areas. These discussions covered: A. Power supplies and control systems; B. Vacuum systems; C. Magnet systems; D. Plasma considerations; E. Cost scaling; F. Superconducting magnet systems; G. Diagnostics; H. Radiation shielding and remote handling; I. Conceptual fusion reactor designs and J. Possibilities for hybrid reactors. Resumes of these discussions, as prepared by each of the session chairmen, are given in this report. Approximately 100 specialists took part in the meeting, including 18 from countries of Western Europe, 8 from Japan, 15 from the USA, and 54 from the USSR. Arrangements were made for a visit of the tokamak facilities at the Kurchatov Institute in Moscow, including the newly completed T-10 device. BRIEF SUMMARY OF THE FOUR PROJECTS (B. B. Kadomtsev) 24 Circular 1.94 1.8x10' at the W6Q&Q 230 350 ±0.05 +6.0 ±15 Air Oore * 2.25 # Mag,Limiter. horiz. H e l d * quad, field coili • 130 * * >ower Grid & **

The widespread adoption of Android devices has attracted the attention of a growing computer security audience. Fundamental weaknesses and subtle design flaws of the Android architecture have been identified, studied and fixed, mostly through techniques from data-flow analysis, runtime protection mechanisms, or changes to the operating system. This paper complements this research by developing a framework for the analysis of Android applications based on typing techniques. We introduce a formal calculus for reasoning on the Android inter-component communication API and a type-and-effect system to statically prevent privilege escalation attacks on well-typed components. Drawing on our abstract framework, we develop a prototype implementation of Lintent, a security type-checker for Android applications integrated with the Android Development Tools suite. We finally discuss preliminary experiences with our tool, which highlight real attacks on existing applications.

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Abstract-We present a framework to automatically evaluate the performance of Mobile Ad-hoc Networks (MANETs) in terms of different kinds of metrics, such as throughput and energy consumption. We use a probabilistic process calculus to model MANETs; we translate process terms into Markov Decision Processes (MDPs) and use the probabilistic model checker PRISM to automatically evaluate the network performance. We present a case study consisting of a network which uses flooding for communicating, and we analyse how time and energy costs vary when pursuing different power control strategies.Index Terms-process algebra; MANETS; model checking; network throughput; energy consumption I. INTRODUCTION Mobile ad-hoc networks (MANETs) are systems of mobile devices communicating with each other through wireless links without a pre-established networking infrastructure. The devices may rely on exhaustible power sources, such as batteries, and hence have strict requirements regarding their energy consumption. For these reasons, when dealing with networks of this type, communication protocols have to face the problem of providing full connectivity between network devices while maintaining good performance, both in terms of throughput and of energy conservation (see, e.g., [16], [17]).We present a framework to automatically evaluate the performance of MANETs in terms of different kinds of metrics. We use the Probabilistic Energy-aware Broadcast Unicast and Multicast (PEBUM) calculus, introduced in [6], to model MANETs. This is a probabilistic process calculus particularly aimed at providing performance analysis in terms of metrics such as energy conservation and throughput.PRISM [11] is a tool for modelling and analysing systems that exhibit a probabilistic behaviour. It supports, among others, the modelling of Markov Decision Processes (MDPs), where nondeterministic and probabilistic aspects coexist.In this paper we exploit the PRISM tool to perform automated, quantitative verification and analysis of wireless networks for a range of performance metrics. Specifically, we develop a parser to translate a PEBUM process term, representing a network, into an MDP model expressed in the PRISM language. Moreover, we formulate the metrics for computing the time and energy cost of a network transmission in terms of reward structures.We demonstrate the effectiveness of our framework on a case study consisting of a MANET which uses flooding to forward messages. We analyse the performance of the

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