Thinking outside the box? Trade union organising strategies and Polish migrant workers in the UK

On the 1 May 2004 the EU witnessed its most challenging enlargement, with the accession of eight post-communist countries (known as the A8)1. Despite the EU’s espoused ‘fundamental freedom’ of labour mobility, the UK was only one of three countries to open up its labour market to entrants from the A8 economies2 Predictions in the UK, that the number of workers seeking jobs in the labour market from post-communist economies would only be modest, could not have been more wrong and attempts to establish accurate figures have been a source of vexation for both national and local government. All A8 workers who are employed in the UK have to register on the Worker Registration Scheme and Poles comprise 66 per cent of A8 migrants (Border and Immigration Agency, 2007). But this is a cumulative total and does not include those who are self-employed or indeed those who have just not registered. There is, however, a growing consensus that this Polish migration constitutes the largest single in-migration ever to the UK (Salt and Millar, 2006). As an interviewee commented ‘what is different with this migration is the scale and in particular the Poles’ (Senior officer TUC Organising Department)

A Faster Counting Protocol for Anonymous Dynamic Networks

We study the problem of counting the number of nodes in a slotted-time communication network, under the challenging assumption that nodes do not have identifiers and the network topology changes frequently. That is, for each time slot links among nodes can change arbitrarily provided that the network is always connected. Tolerating dynamic topologies is crucial in face of mobility and unreliable communication whereas, even if identifiers are available, it might be convenient to ignore them in massive networks with changing topology. Counting is a fundamental task in distributed computing since knowing the size of the system often facilitates the design of solutions for more complex problems. Currently, the best upper bound proved on the running time to compute the exact network size is double-exponential. However, only linear complexity lower bounds are known, leaving open the question of whether efficient Counting protocols for Anonymous Dynamic Networks exist or not. In this paper we make a significant step towards answering this question by presenting a distributed Counting protocol for Anonymous Dynamic Networks which has exponential time complexity. Our algorithm ensures that eventually every node knows the exact size of the system and stops executing the algorithm. Previous Counting protocols have either double-exponential time complexity, or they are exponential but do not terminate, or terminate but do not provide running-time guarantees, or guarantee only an exponential upper bound on the network size. Other protocols are heuristic and do not guarantee the correct count

Grain‐energy release governs mobility of debris flow due to solid–liquid mass release

Debris flows often exhibit high mobility, leading to extensive hazards far from their sources. Although it is known that debris flow mobility increases with initial volume, the underlying mechanism remains uncertain. Here, we reconstruct the mobility–volume relation for debris flows using a recent depth‐averaged two‐phase flow model without evoking a reduced friction coefficient, challenging currently prevailing friction‐reduction hypotheses. Physical experimental debris flows driven by solid–liquid mass release and extended numerical cases at both laboratory and field scales are resolved by the model. For the first time, we probe into the energetics of the debris flows and find that, whilst the energy balance holds and fine and coarse grains play distinct roles in debris flow energetics, the grains as a whole release energy to the liquid due to inter‐phase and inter‐grain size interactions, and this grain‐energy release correlates closely with mobility. Despite uncertainty arising from the model closures, our results provide insight into the fundamental mechanisms operating in debris flows. We propose that debris flow mobility is governed by grain‐energy release, thereby facilitating a bridge between mobility and internal energy transfer. The initial volume of debris flow is inadequate for characterizing debris flow mobility, and a friction‐reduction mechanism is not a prerequisite for the high mobility of debris flows. By contrast, inter‐phase and inter‐grain size interactions play primary roles and should be incorporated explicitly in debris flow models. Our findings are qualitatively encouraging and physically meaningful, providing implications not only for assessing future debris flow hazards and informing mitigation and adaptation strategies, but also for unravelling a spectrum of earth surface processes including heavily sediment‐laden floods, subaqueous debris flows and turbidity currents in rivers, reservoirs, estuaries, and ocean

Architecture and Protocols for Service and Application Deployment in Resource Aware Ubiquitous Environments

Realizing the potential of pervasive computing will be predicated upon the availability of a flexible, mobility-aware infrastructure and the technologies to support seamless service management, provisioning and delivery. Despite the advances in routing and media access control technologies, little progress has been made towards large-scale deployment of services and applications in pervasive and ubiquitous environments. The lack of a fixed infrastructure, coupled with the time-varying characteristics of the underlying network topology, make service delivery challenging. The goal of this research is to address the fundamental design issues of a service infrastructure for ubiquitous environments and provide a comprehensive solution which is robust, scalable, secure and takes into consideration node mobility and resource constraints. We discuss the main functionalities of the proposed architecture, describe the algorithms for registration and discovery and present a power-aware location-driven message forwarding algorithm to enable node interaction in this architecture. We also provide security schemes to ensure user privacy in this architecture. The proposed architecture was evaluated through theuse of simulations. The results show that the service architecture is scalable and robust, even when node mobility is high. The comparative analysis shows that our message forwarding algorithm consistently outperforms contemporary location-driven algorithms. Furthermore, thisresearch work was implemented as a proof-of-concept implementation and tested on a real world scenario

LTE-advanced self-organizing network conflicts and coordination algorithms

Self-organizing network (SON) functions have been introduced in the LTE and LTEAdvanced standards by the Third Generation Partnership Project as an excellent solution that promises enormous improvements in network performance. However, the most challenging issue in implementing SON functions in reality is the identification of the best possible interactions among simultaneously operating and even conflicting SON functions in order to guarantee robust, stable, and desired network operation. In this direction, the first step is the comprehensive modeling of various types of conflicts among SON functions, not only to acquire a detailed view of the problem, but also to pave the way for designing appropriate Self-Coordination mechanisms among SON functions. In this article we present a comprehensive classification of SON function conflicts, which leads the way for designing suitable conflict resolution solutions among SON functions and implementing SON in reality. Identifying conflicting and interfering relations among autonomous network management functionalities is a tremendously complex task. We demonstrate how analysis of fundamental trade-offs among performance metrics can us to the identification of potential conflicts. Moreover, we present analytical models of these conflicts using reference signal received power plots in multi-cell environments, which help to dig into the complex relations among SON functions. We identify potential chain reactions among SON function conflicts that can affect the concurrent operation of multiple SON functions in reality. Finally, we propose a selfcoordination framework for conflict resolution among multiple SON functions in LTE/LTEAdvanced networks, while highlighting a number of future research challenges for conflict-free operation of SON