A Quantitative Study of Two Attacks

We use a special operational semantics which helps us in predicting quantitative measures on systems describing cryptographic protocols: We also consider a possible attacker. The transitions of the system carry enhanced labels. We assign rates to transitions by only looking at these labels. We then map transition systems to Markov chains and evaluate performance of systems, using standard tools

Presupposition and Dissociation in Discourse : a corpus Study

This paper combines different theoretical and methodological approaches for the analysis of discourse, focusing in particular on argumentative structures. At a first level an attempt is made to include argumentation in critical discourse analysis in order to extend the analysis of interaction between “structures of discourse” and “structures of ideologies” (van Dijk 1995) to higher levels of language description. At a second level the study will integrate the qualitative approaches of critical discourse analysis and argumentation theory with the quantitative tools of corpus linguistics, so that the analysis can be carried out on a representative amount of texts and in a more systematic way. Even though corpus linguistics tends to be focused on meanings localized at the level of words, while argumentative structures stretch out through longer units of text, an integration can be attempted by circumscribing the enquiry to those aspects of argumentation which are signalled by indicators, and are therefore electronically retrievable. In particular, this paper investigates the use of dissociation and presupposition in a corpus of newspaper articles published in the run up to the war on Iraq. Both structures respond to retrievability criteria while being powerful instruments to convey ideologically oriented messages

Modelling biochemical pathways through enhanced π-calculus

AbstractWe use the π-calculus to model the evolution of biochemical systems, taking advantage of their similarities with global computation applications. First, we present a reduction semantics for the π-calculus from which causality and concurrency can be mechanically derived. We prove that our semantics agrees with the causal definitions presented in the literature. We also extend our semantics to model biological compartments. Then, we show the applicability of our proposal on a couple of biological examples

Indicators of argumentation in arbitration awards : a diachronic perspective

This paper investigates the international arbitration award from the perspective of genre hybridization, with a view to verifying the claim that boundaries in the discursive practices of arbitration and litigation have been progressively blurring, as an effect of \u2018colonization\u2019 of the former on the part of the latter. Starting from the assumption that recourse to argumentation is a distinguishing feature of litigative discourse, and particularly of the judgement, where the court needs to justify their decision, this paper focuses on the incidence of indicators of argumentation in a corpus of arbitration awards spanning over two decades, aiming to ascertain whether their use has increased over time. The quantitative analysis is integrated with close reading of selected texts, relying on the categories of Werlich\u2019s text grammar (1983), in order to support the quantitative findings with insights at the lexico-grammatical and textual level. The analysis shows a marked increase in the recourse to argumentative strategies over time, thus providing evidence of the increasing influence of litigation on arbitration

Design and initial testing of a high speed 45 kW switched reluctance drive for aerospace application

This paper presents innovative research towards the development of a 45 kW high speed switched reluctance drive as an alternative starter-generator for future aero-engines. To perform such a function the machine had to be designed with a very wide constant power-speed range. During engine-start/motoring mode, a peak torque demand of 54 Nm at 8 krpm was met, whilst in generating mode, 19.2-32 krpm, the machine was designed to deliver a constant power of 45 kW. The key enabling feature of the design lies in the novel rotor structure developed so as to allow for such a wide speed range. The results presented, are those measured during the initial testing phase and validate the system design and performance in the low-speed region with the machine operated in starting-mode. The measured machine power density is at 9.8 kW/ltr, whilst the global system efficiency is at 82%

Smart transportation systems (STSs) in critical conditions

In the context of smart transportation systems (STSs) in smart cities, the use of applications that can help in case of critical conditions is a key point. Examples of critical conditions may be natural-disaster events such as earthquakes, hurricanes, floods, and manmade ones such as terrorist attacks and toxic waste spills. Disaster events are often combined with the destruction of the local telecommunication infrastructure, if any, and this implies real problems to the rescue operations.The quick deployment of a telecommunication infrastructure is essential for emergency and safety operations as well as the rapid network reconfigurability, the availability of open source software, the efficient interoperability, and the scalability of the technological solutions. The topic is very hot and many research groups are focusing on these issues. Consequently, the deployment of a smart network is fundamental. It is needed to support both applications that can tolerate delays and applications requiring dedicated resources for real-time services such as traffic alert messages, and public safety messages. The guarantee of quality of service (QoS) for such applications is a key requirement.In this chapter we will analyze the principal issues of the networking aspects and will propose a solution mainly based on software defined networking (SDN). We will evaluate the benefit of such paradigm in the mentioned context focusing on the incremental deployment of such solution in the existing metropolitan networks and we will design a "QoS App" able to manage the quality of service on top of the SDN controller

Revealing the trajectories of KLAIM tuples, statically

Klaim (Kernel Language for Agents Interaction and Mobility) has been devised to design distributed applications composed by many components deployed over the nodes of a distributed infrastructure and to offer programmers primitive constructs for communicating, distributing and retrieving data. Data could be sensitive and some nodes could not be secure. As a consequence it is important to track data in their traversal of the network. To this aim, we propose a Control Flow Analysis that over-approximates the behaviour of Klaim processes and tracks how tuple data can move in the network

Synchronous reluctance motor iron losses: considering machine non-linearity at MTPA, FW, and MTPV operating conditions

Synchronous reluctance machine has high flux density fluctuations in the iron due to the high harmonics results from the rotor anisotropy. Thus, an accurate computation of the iron losses is of paramount importance, especially during the design stage. In this paper, a non-linear analytical model considering the magnetic iron saturation and the slotting effect is proposed. The model estimates accurately the iron losses at a wide range of operating speed. In addition, the accuracy of the non-linear model when the machine is highly saturated, i.e. when it works along the MTPA trajectory, is presented and verified. The model presented is general and can be applied to other configurations. A 36-slot four-pole machine, with three flux-barriers per pole is considered as a case study. Finite element analysis is used to validate the results achieved by means of the non-linear analytical model. Furthermore, an experimental setup is built to validate the simulation results

History and recent advancements of electric propulsion and integrated electrical power systems for commercial & naval vessels

Due to developments in power electronics, electric machines, energy storage and control, electric propulsion and integrated electrical power systems have become major trends for commercial and naval vessels. This is mainly due to the fact that the use of electric propulsion and integrated power systems can improve efficiency and fuel consumption while reducing noise and vibration when compared to conventional systems. Such advantages are extremely attractive to vessel owners due to increasingly stringent emission requirements, especially in environmental control areas, from the international maritime organization. This paper aims to summarize the recent advancement of marine power systems including propulsion systems, electrical distribution systems and novel loads

Grid Parameter estimation using Model Predictive Direct Power Control

This paper presents a novel Finite Control Set Model Predictive Control (FS-MPC) approach for grid-connected converters. The control performance of such converters may get largely affected by variations in the supply impedance, especially for systems with low Short Circuit Ratio (SCR) values. A novel idea for estimating the supply impedance variation, and hence the grid voltage, using an algorithm embedded in the MPC is presented in this paper. The estimation approach is based on the difference in grid voltage magnitudes at two consecutive sampling instants, calculated on the basis of supply currents and converter voltages directly within the MPC algorithm, achieving a fast estimation and integration between the controller and the impedance estimator. The proposed method has been verified, using simulation and experiments, on a 3-phase 2-level converter