Abstract
This paper proposes a control scheme that allows doubly fed induction wind generators (DFIWG) to participate effectively in system frequency regulation. In this control approach, wind generators operate according to a deloaded optimum power extraction curve such that the active power provided by each wind turbine increases or decreases during system frequency changes. The control strategy defined at the wind generator to supply primary frequency regulation capability exploits a combination of control of the static converters and pitch control, adjusting the rotor speed and the active power according to the deloaded optimum power extraction curve. Results obtained in a small isolated system are presented to demonstrate the effectiveness of the approach.

Abstract

Abstract
Circular programs are a powerful technique to express multiple traversal algorithms as a single traversal function in a lazy setting. In this paper, we present a shortcut deforestation technique to calculate circular programs. The technique we propose takes as input the composition of two functions, such that the first builds an intermediate structure and some additional context information which are then processed by the second one, to produce the final result. Our transformation into circular programs achieves intermediate structure deforestation and multiple traversal elimination. Furthermore, the calculated programs preserve the termination properties of the original ones.

Abstract
We consider the problem of securing routing information in Mobile Ad-hoc Networks (MANETs). Focusing on the Optimized Link State Routing protocol, we devise a feedback reputation mechanism which assesses the integrity of routing control traffic by correlating local routing data with feedback messages sent by the receivers of control traffic. Based on this assessment, misbehaving nodes are shown to be reliably detected and can be adequately punished in terms of their ability to communicate through the network. To the best of our knowledge, this is the first practical implementation of a reputation mechanism in a standardized proactive routing protocol for MANETs.

Abstract
This paper presents techniques to model circular lazy programs in a strict, purely functional setting. Circular lazy programs model any algorithm based on multiple traversals over a recursive data structure as a single traversal function. Such elegant and concise circular programs are defined in a (strict or lazy) functional language and they are transformed into efficient strict and deforested, multiple traversal programs by using attribute grammars-based techniques. Moreover, we use standard slicing techniques to slice such circular lazy programs. We have expressed these transformations as an Haskell library and two tools have been constructed: the HaCirc tool that refactors Haskell lazy circular programs into strict ones, and the OCirc tool that extends Ocaml with circular definitions allowing programmers to write circular programs in Ocaml notation, which are transformed into strict Ocaml programs before they are executed. The first benchmarks of the different implementations are presented and show that for algorithms relying on a large number of traversals the resulting strict, deforested programs are more efficient than the lazy ones, both in terms of runtime and memory consumption. Copyright © 2007 ACM.

Abstract
The increasing requirement for ubiquitous access of the users, enable the seamless support of different networks, with different technologies, and also with different types, such as moving networks and ad-hoc networks. This paper describes the Ad-hoc network integration architecture being developed inside the IST project Daidalos II. The main purpose of this architecture is to seamlessly support the movement of nodes between ad-hoc and infrastructure networks, maintaining in the ad-hoc networks all the features being supported in the infrastructure, such as, efficient routing for unicast and multicast flows, distributed QoS mechanisms' security, and seamless mobility, including multihoming support.