Multi-Agent Systems

This Special Issue ""Multi-Agent Systems"" gathers original research articles reporting results on the steadily growing area of agent-oriented computing and multi-agent systems technologies. After more than 20 years of academic research on multi-agent systems (MASs), in fact, agent-oriented models and technologies have been promoted as the most suitable candidates for the design and development of distributed and intelligent applications in complex and dynamic environments. With respect to both their quality and range, the papers in this Special Issue already represent a meaningful sample of the most recent advancements in the field of agent-oriented models and technologies. In particular, the 17 contributions cover agent-based modeling and simulation, situated multi-agent systems, socio-technical multi-agent systems, and semantic technologies applied to multi-agent systems. In fact, it is surprising to witness how such a limited portion of MAS research already highlights the most relevant usage of agent-based models and technologies, as well as their most appreciated characteristics. We are thus confident that the readers of Applied Sciences will be able to appreciate the growing role that MASs will play in the design and development of the next generation of complex intelligent systems. This Special Issue has been converted into a yearly series, for which a new call for papers is already available at the Applied Sciences journal’s website: https://www.mdpi.com/journal/applsci/special_issues/Multi-Agent_Systems_2019

Recent changes in the global rail industry: facing the challenge of increased flexibility

This paper discusses how the current trend towards increased private participation in the rail industry is reshaping the way in which Governments should address the main regulatory challenges arising from the particular economic and technical characteristics of this industry. We review the role of railroads in the last two decades and examine the characteristics of the most relevant processes of private participation around the world. The lessons learned from these changes suggest that many of the traditional regulatory paradigms in this industry are being replaced by more flexible schemes of public intervention. Although this change does not fully preclude direct participation by the Government, it seems that the traditional monopolistic rail company is dead as the dominant model around the world, and new forms, such as franchises or concessions competing on the tracks are progressively gaining relevance

Regulating privatized rail transport

Traditionally, transport regulation has been viewed as an exercise in second-best optimization, acknowledging the existence of huge information problems. Then the rail industry was deeply restructured worldwide to halt erosion of the sector's share of transportation markets. Restructuring took different forms in different countries, ranging from simple reorganization measures to extreme restructuring -with the private sector increasingly participating in the sector and with the provision of infrastructure separated from the provision of services. The authors argue that regulation of the rail industry cannot remain unaffected by these changes. New regulatory scenarios and issues have emerged. For example, contracts have to be defined for private participation and quality surveillance instruments must be defined. Traditional price controls have to be adapted to, and mechanisms designed to manage and plan infrastructure investments in, the new environment. Restructuring has brought new problems, too. Where licenses have been used, for example, several concessionaires have been unable to meet the objectives spelled out in the concession contract. Contracts should be flexible enough to take account of novel situations that may affect company performance. And yet, for the system to be credible, there cannot be systematic, unjustified deviations from the franchise objectives. Regulation of the sector should be simple and flexible, with license contracts designed to include the private sector and with industry organization adapted to local circumstances. Regulation should be governed by principles that foster competition and market mechanisms, wherever possible. At the same time, it should provide a stable legal and institutional framework for economic activity. Otherwise, regulators should refrain from intervening in the market-unless the goal of economic efficiency (subject to the socially demanded levelof equity) is in jeopardy.Municipal Financial Management,Banks&Banking Reform,Decentralization,Enterprise Development&Reform,Public Sector Economics&Finance,Railways Transport,Banks&Banking Reform,Municipal Financial Management,Water and Industry,Public Sector Economics&Finance

Towards a Climate-Neutral Europe

This book explains the EU’s climate policies in an accessible way, to demonstrate the step-by-step approach that has been used to develop these policies, and the ways in which they have been tested and further improved in the light of experience. The latest changes to the legislation are fully explained throughout. The chapters throughout this volume show that no single policy instrument can bring down greenhouse gas emissions. The challenge facing the EU, as for many countries that have made pledges under the Paris Agreement, is to put together a toolbox of policy instruments that is coherent, delivers emissions reductions, and is cost-effective. The book stands out by the fact it covers the EU’s emissions trading system, the energy sector and other economic sectors, including their development in the context of international climate policy. This accessible book will be of great relevance to students, scholars and policy makers alike

Integrating Consumer Flexibility in Smart Grid and Mobility Systems - An Online Optimization and Online Mechanism Design Approach

Consumer flexibility may provide an important lever to align supply and demand in service systems. However, harnessing dispersed flexibility endowments in the presence of self-interested agents requires appropriate incentive structures. This thesis quantifies the potential value of consumers\u27 flexibility in smart grid and mobility systems. In order to include incentives, online optimization approaches are augmented with methods from online mechanism design

DRIVE: A Distributed Economic Meta-Scheduler for the Federation of Grid and Cloud Systems

The computational landscape is littered with islands of disjoint resource providers including commercial Clouds, private Clouds, national Grids, institutional Grids, clusters, and data centers. These providers are independent and isolated due to a lack of communication and coordination, they are also often proprietary without standardised interfaces, protocols, or execution environments. The lack of standardisation and global transparency has the effect of binding consumers to individual providers. With the increasing ubiquity of computation providers there is an opportunity to create federated architectures that span both Grid and Cloud computing providers effectively creating a global computing infrastructure. In order to realise this vision, secure and scalable mechanisms to coordinate resource access are required. This thesis proposes a generic meta-scheduling architecture to facilitate federated resource allocation in which users can provision resources from a range of heterogeneous (service) providers. Efficient resource allocation is difficult in large scale distributed environments due to the inherent lack of centralised control. In a Grid model, local resource managers govern access to a pool of resources within a single administrative domain but have only a local view of the Grid and are unable to collaborate when allocating jobs. Meta-schedulers act at a higher level able to submit jobs to multiple resource managers, however they are most often deployed on a per-client basis and are therefore concerned with only their allocations, essentially competing against one another. In a federated environment the widespread adoption of utility computing models seen in commercial Cloud providers has re-motivated the need for economically aware meta-schedulers. Economies provide a way to represent the different goals and strategies that exist in a competitive distributed environment. The use of economic allocation principles effectively creates an open service market that provides efficient allocation and incentives for participation. The major contributions of this thesis are the architecture and prototype implementation of the DRIVE meta-scheduler. DRIVE is a Virtual Organisation (VO) based distributed economic metascheduler in which members of the VO collaboratively allocate services or resources. Providers joining the VO contribute obligation services to the VO. These contributed services are in effect membership “dues” and are used in the running of the VOs operations – for example allocation, advertising, and general management. DRIVE is independent from a particular class of provider (Service, Grid, or Cloud) or specific economic protocol. This independence enables allocation in federated environments composed of heterogeneous providers in vastly different scenarios. Protocol independence facilitates the use of arbitrary protocols based on specific requirements and infrastructural availability. For instance, within a single organisation where internal trust exists, users can achieve maximum allocation performance by choosing a simple economic protocol. In a global utility Grid no such trust exists. The same meta-scheduler architecture can be used with a secure protocol which ensures the allocation is carried out fairly in the absence of trust. DRIVE establishes contracts between participants as the result of allocation. A contract describes individual requirements and obligations of each party. A unique two stage contract negotiation protocol is used to minimise the effect of allocation latency. In addition due to the co-op nature of the architecture and the use of secure privacy preserving protocols, DRIVE can be deployed in a distributed environment without requiring large scale dedicated resources. This thesis presents several other contributions related to meta-scheduling and open service markets. To overcome the perceived performance limitations of economic systems four high utilisation strategies have been developed and evaluated. Each strategy is shown to improve occupancy, utilisation and profit using synthetic workloads based on a production Grid trace. The gRAVI service wrapping toolkit is presented to address the difficulty web enabling existing applications. The gRAVI toolkit has been extended for this thesis such that it creates economically aware (DRIVE-enabled) services that can be transparently traded in a DRIVE market without requiring developer input. The final contribution of this thesis is the definition and architecture of a Social Cloud – a dynamic Cloud computing infrastructure composed of virtualised resources contributed by members of a Social network. The Social Cloud prototype is based on DRIVE and highlights the ease in which dynamic DRIVE markets can be created and used in different domains

Towards a Climate-Neutral Europe

This book explains the EU’s climate policies in an accessible way, to demonstrate the step-by-step approach that has been used to develop these policies, and the ways in which they have been tested and further improved in the light of experience. The latest changes to the legislation are fully explained throughout. The chapters throughout this volume show that no single policy instrument can bring down greenhouse gas emissions. The challenge facing the EU, as for many countries that have made pledges under the Paris Agreement, is to put together a toolbox of policy instruments that is coherent, delivers emissions reductions, and is cost-effective. The book stands out by the fact it covers the EU’s emissions trading system, the energy sector and other economic sectors, including their development in the context of international climate policy. This accessible book will be of great relevance to students, scholars and policy makers alike

Supercomputing futures : the next sharing paradigm for HPC resources : economic model, market analysis and consequences for the Grid

À la croisée des chemins du génie informatique, de la finance et de l'économétrie, cette thèse se veut fondamentalement un exercice en ingénierie économique dont l' objectif est de contribuer un système novateur, durable et adaptatif pour le partage de resources de calcul haute-performance. Empruntant à la finance fondamentale et à l'analyse technique, le modèle proposé construit des ratios et des indices de marché à partir de statistiques transactionnelles. Cette approche, encourageant les comportements stratégiques, pave la voie à une métaphore de partage plus efficace pour la Grid, où l'échange de ressources se voit maintenant pondéré. Le concept de monnaie de Grid, un instrument beaucoup plus liquide et utilisable que le troc de resources comme telles est proposé: les Grid Credits. Bien que les indices proposés ne doivent pas être considérés comme des indicateurs absolus et contraignants, ils permettent néanmoins aux négociants de se faire une idée de la valeur au marché des différentes resources avant de se positionner. Semblable sur de multiples facettes aux bourses de commodités, le Grid Exchange, tel que présenté, permet l'échange de resources via un mécanisme de double-encan. Néanmoins, comme les resources de super-calculateurs n'ont rien de standardisé, la plate-forme permet l'échange d'ensemble de commodités, appelés requirement sets, pour les clients, et component sets, pour les fournisseurs. Formellement, ce modèle économique n'est qu'une autre instance de la théorie des jeux non-coopératifs, qui atteint éventuellement ses points d'équilibre. Suivant les règles du "libre-marché", les utilisateurs sont encouragés à spéculer, achetant, ou vendant, à leur bon vouloir, l'utilisation des différentes composantes de superordinateurs. En fin de compte, ce nouveau paradigme de partage de resources pour la Grid dresse la table à une nouvelle économie et une foule de possibilités. Investissement et positionnement stratégique, courtiers, spéculateurs et même la couverture de risque technologique sont autant d'avenues qui s'ouvrent à l'horizon de la recherche dans le domaine