50 research outputs found
Cloud computing resource scheduling and a survey of its evolutionary approaches
A disruptive technology fundamentally transforming the way that computing services are delivered, cloud computing offers information and communication technology users a new dimension of convenience of resources, as services via the Internet. Because cloud provides a finite pool of virtualized on-demand resources, optimally scheduling them has become an essential and rewarding topic, where a trend of using Evolutionary Computation (EC) algorithms is emerging rapidly. Through analyzing the cloud computing architecture, this survey first presents taxonomy at two levels of scheduling cloud resources. It then paints a landscape of the scheduling problem and solutions. According to the taxonomy, a comprehensive survey of state-of-the-art approaches is presented systematically. Looking forward, challenges and potential future research directions are investigated and invited, including real-time scheduling, adaptive dynamic scheduling, large-scale scheduling, multiobjective scheduling, and distributed and parallel scheduling. At the dawn of Industry 4.0, cloud computing scheduling for cyber-physical integration with the presence of big data is also discussed. Research in this area is only in its infancy, but with the rapid fusion of information and data technology, more exciting and agenda-setting topics are likely to emerge on the horizon
Mobile Ad Hoc Networks
Guiding readers through the basics of these rapidly emerging networks to more advanced concepts and future expectations, Mobile Ad hoc Networks: Current Status and Future Trends identifies and examines the most pressing research issues in Mobile Ad hoc Networks (MANETs). Containing the contributions of leading researchers, industry professionals, and academics, this forward-looking reference provides an authoritative perspective of the state of the art in MANETs. The book includes surveys of recent publications that investigate key areas of interest such as limited resources and the mobility of mobile nodes. It considers routing, multicast, energy, security, channel assignment, and ensuring quality of service. Also suitable as a text for graduate students, the book is organized into three sections: Fundamentals of MANET Modeling and SimulationâDescribes how MANETs operate and perform through simulations and models Communication Protocols of MANETsâPresents cutting-edge research on key issues, including MAC layer issues and routing in high mobility Future Networks Inspired By MANETsâTackles open research issues and emerging trends Illustrating the role MANETs are likely to play in future networks, this book supplies the foundation and insight you will need to make your own contributions to the field. It includes coverage of routing protocols, modeling and simulations tools, intelligent optimization techniques to multicriteria routing, security issues in FHAMIPv6, connecting moving smart objects to the Internet, underwater sensor networks, wireless mesh network architecture and protocols, adaptive routing provision using Bayesian inference, and adaptive flow control in transport layer using genetic algorithms
Communication Efficiency in Information Gathering through Dynamic Information Flow
This thesis addresses the problem of how to improve the performance of multi-robot information gathering tasks by actively controlling the rate of communication between robots. Examples of such tasks include cooperative tracking and cooperative environmental monitoring. Communication is essential in such systems for both decentralised data fusion and decision making, but wireless networks impose capacity constraints that are frequently overlooked. While existing research has focussed on improving available communication throughput, the aim in this thesis is to develop algorithms that make more efficient use of the available communication capacity. Since information may be shared at various levels of abstraction, another challenge is the decision of where information should be processed based on limits of the computational resources available. Therefore, the flow of information needs to be controlled based on the trade-off between communication limits, computation limits and information value. In this thesis, we approach the trade-off by introducing the dynamic information flow (DIF) problem. We suggest variants of DIF that either consider data fusion communication independently or both data fusion and decision making communication simultaneously. For the data fusion case, we propose efficient decentralised solutions that dynamically adjust the flow of information. For the decision making case, we present an algorithm for communication efficiency based on local LQ approximations of information gathering problems. The algorithm is then integrated with our solution for the data fusion case to produce a complete communication efficiency solution for information gathering. We analyse our suggested algorithms and present important performance guarantees. The algorithms are validated in a custom-designed decentralised simulation framework and through field-robotic experimental demonstrations
Mobile Ad Hoc Networks
Guiding readers through the basics of these rapidly emerging networks to more advanced concepts and future expectations, Mobile Ad hoc Networks: Current Status and Future Trends identifies and examines the most pressing research issues in Mobile Ad hoc Networks (MANETs). Containing the contributions of leading researchers, industry professionals, and academics, this forward-looking reference provides an authoritative perspective of the state of the art in MANETs. The book includes surveys of recent publications that investigate key areas of interest such as limited resources and the mobility of mobile nodes. It considers routing, multicast, energy, security, channel assignment, and ensuring quality of service. Also suitable as a text for graduate students, the book is organized into three sections: Fundamentals of MANET Modeling and SimulationâDescribes how MANETs operate and perform through simulations and models Communication Protocols of MANETsâPresents cutting-edge research on key issues, including MAC layer issues and routing in high mobility Future Networks Inspired By MANETsâTackles open research issues and emerging trends Illustrating the role MANETs are likely to play in future networks, this book supplies the foundation and insight you will need to make your own contributions to the field. It includes coverage of routing protocols, modeling and simulations tools, intelligent optimization techniques to multicriteria routing, security issues in FHAMIPv6, connecting moving smart objects to the Internet, underwater sensor networks, wireless mesh network architecture and protocols, adaptive routing provision using Bayesian inference, and adaptive flow control in transport layer using genetic algorithms
Network-on-Chip
Addresses the Challenges Associated with System-on-Chip Integration Network-on-Chip: The Next Generation of System-on-Chip Integration examines the current issues restricting chip-on-chip communication efficiency, and explores Network-on-chip (NoC), a promising alternative that equips designers with the capability to produce a scalable, reusable, and high-performance communication backbone by allowing for the integration of a large number of cores on a single system-on-chip (SoC). This book provides a basic overview of topics associated with NoC-based design: communication infrastructure design, communication methodology, evaluation framework, and mapping of applications onto NoC. It details the design and evaluation of different proposed NoC structures, low-power techniques, signal integrity and reliability issues, application mapping, testing, and future trends. Utilizing examples of chips that have been implemented in industry and academia, this text presents the full architectural design of components verified through implementation in industrial CAD tools. It describes NoC research and developments, incorporates theoretical proofs strengthening the analysis procedures, and includes algorithms used in NoC design and synthesis. In addition, it considers other upcoming NoC issues, such as low-power NoC design, signal integrity issues, NoC testing, reconfiguration, synthesis, and 3-D NoC design. This text comprises 12 chapters and covers: The evolution of NoC from SoCâits research and developmental challenges NoC protocols, elaborating flow control, available network topologies, routing mechanisms, fault tolerance, quality-of-service support, and the design of network interfaces The router design strategies followed in NoCs The evaluation mechanism of NoC architectures The application mapping strategies followed in NoCs Low-power design techniques specifically followed in NoCs The signal integrity and reliability issues of NoC The details of NoC testing strategies reported so far The problem of synthesizing application-specific NoCs Reconfigurable NoC design issues Direction of future research and development in the field of NoC Network-on-Chip: The Next Generation of System-on-Chip Integration covers the basic topics, technology, and future trends relevant to NoC-based design, and can be used by engineers, students, and researchers and other industry professionals interested in computer architecture, embedded systems, and parallel/distributed systems
Energy and performance-optimized scheduling of tasks in distributed cloud and edge computing systems
Infrastructure resources in distributed cloud data centers (CDCs) are shared by heterogeneous applications in a high-performance and cost-effective way. Edge computing has emerged as a new paradigm to provide access to computing capacities in end devices. Yet it suffers from such problems as load imbalance, long scheduling time, and limited power of its edge nodes. Therefore, intelligent task scheduling in CDCs and edge nodes is critically important to construct energy-efficient cloud and edge computing systems. Current approaches cannot smartly minimize the total cost of CDCs, maximize their profit and improve quality of service (QoS) of tasks because of aperiodic arrival and heterogeneity of tasks. This dissertation proposes a class of energy and performance-optimized scheduling algorithms built on top of several intelligent optimization algorithms. This dissertation includes two parts, including background work, i.e., Chapters 3â6, and new contributions, i.e., Chapters 7â11.
1) Background work of this dissertation.
Chapter 3 proposes a spatial task scheduling and resource optimization method to minimize the total cost of CDCs where bandwidth prices of Internet service providers, power grid prices, and renewable energy all vary with locations. Chapter 4 presents a geography-aware task scheduling approach by considering spatial variations in CDCs to maximize the profit of their providers by intelligently scheduling tasks. Chapter 5 presents a spatio-temporal task scheduling algorithm to minimize energy cost by scheduling heterogeneous tasks among CDCs while meeting their delay constraints. Chapter 6 gives a temporal scheduling algorithm considering temporal variations of revenue, electricity prices, green energy and prices of public clouds.
2) Contributions of this dissertation.
Chapter 7 proposes a multi-objective optimization method for CDCs to maximize their profit, and minimize the average loss possibility of tasks by determining task allocation among Internet service providers, and task service rates of each CDC. A simulated annealing-based bi-objective differential evolution algorithm is proposed to obtain an approximate Pareto optimal set. A knee solution is selected to schedule tasks in a high-profit and high-quality-of-service way. Chapter 8 formulates a bi-objective constrained optimization problem, and designs a novel optimization method to cope with energy cost reduction and QoS improvement. It jointly minimizes both energy cost of CDCs, and average response time of all tasks by intelligently allocating tasks among CDCs and changing task service rate of each CDC. Chapter 9 formulates a constrained bi-objective optimization problem for joint optimization of revenue and energy cost of CDCs. It is solved with an improved multi-objective evolutionary algorithm based on decomposition. It determines a high-quality trade-off between revenue maximization and energy cost minimization by considering CDCsâ spatial differences in energy cost while meeting tasksâ delay constraints. Chapter 10 proposes a simulated annealing-based bees algorithm to find a close-to-optimal solution. Then, a fine-grained spatial task scheduling algorithm is designed to minimize energy cost of CDCs by allocating tasks among multiple green clouds, and specifies running speeds of their servers. Chapter 11 proposes a profit-maximized collaborative computation offloading and resource allocation algorithm to maximize the profit of systems and guarantee that response time limits of tasks are met in cloud-edge computing systems. A single-objective constrained optimization problem is solved by a proposed simulated annealing-based migrating birds optimization. This dissertation evaluates these algorithms, models and software with real-life data and proves that they improve scheduling precision and cost-effectiveness of distributed cloud and edge computing systems
Conception des réseaux maillés sans fil à multiples-radios multiples-canaux
Généralement, les problÚmes de conception de réseaux consistent à sélectionner les arcs et
les sommets dâun graphe G de sorte que la fonction coĂ»t est optimisĂ©e et lâensemble de
contraintes impliquant les liens et les sommets dans G sont respectĂ©es. Une modification dans le critĂšre dâoptimisation et/ou dans lâensemble de contraintes mĂšne Ă une nouvelle reprĂ©sentation dâun problĂšme diffĂ©rent. Dans cette thĂšse, nous nous intĂ©ressons au problĂšme de conception dâinfrastructure de rĂ©seaux maillĂ©s sans fil (WMN- Wireless Mesh Network en Anglais) oĂč nous montrons que la conception de tels rĂ©seaux se transforme dâun
problĂšme dâoptimisation standard (la fonction coĂ»t est optimisĂ©e) Ă un problĂšme
dâoptimisation Ă plusieurs objectifs, pour tenir en compte de nombreux aspects, souvent
contradictoires, mais néanmoins incontournables dans la réalité. Cette thÚse, composée de
trois volets, propose de nouveaux modĂšles et algorithmes pour la conception de WMNs oĂč
rien nâest connu Ă lâ avance.
Le premiervolet est consacrĂ© Ă lâoptimisation simultanĂ©e de deux objectifs
équitablement importants : le coût et la performance du réseau en termes de débit. Trois
modĂšles bi-objectifs qui se diffĂ©rent principalement par lâapproche utilisĂ©e pour maximiser
la performance du réseau sont proposés, résolus et comparés.
Le deuxiĂšme volet traite le problĂšme de placement de passerelles vu son impact sur la
performance et lâextensibilitĂ© du rĂ©seau. La notion de contraintes de sauts (hop constraints)
est introduite dans la conception du réseau pour limiter le délai de transmission. Un nouvel
algorithme basé sur une approche de groupage est proposé afin de trouver les positions
stratĂ©giques des passerelles qui favorisent lâextensibilitĂ© du rĂ©seau et augmentent sa
performance sans augmenter considérablement le coût total de son installation.
Le dernier volet adresse le problÚme de fiabilité du réseau dans la présence de pannes
simples. PrĂ©voir lâinstallation des composants redondants lors de la phase de conception
peut garantir des communications fiables, mais au détriment du coût et de la performance
du rĂ©seau. Un nouvel algorithme, basĂ© sur lâapproche thĂ©orique de dĂ©composition en
oreilles afin dâinstaller le minimum nombre de routeurs additionnels pour tolĂ©rer les pannes
simples, est développé.
Afin de résoudre les modÚles proposés pour des réseaux de taille réelle, un algorithme
évolutionnaire (méta-heuristique), inspiré de la nature, est développé. Finalement, les
méthodes et modÚles proposés on été évalués par des simulations empiriques et
dâĂ©vĂ©nements discrets.Generally, network design problems consist of selecting links and vertices of a graph G so
that a cost function is optimized and all constraints involving links and the vertices in G are
met. A change in the criterion of optimization and/or the set of constraints leads to a new
representation of a different problem. In this thesis, we consider the problem of designing
infrastructure Wireless Mesh Networks (WMNs) where we show that the design of such
networks becomes an optimization problem with multiple objectives instead of a standard
optimization problem (a cost function is optimized) to take into account many aspects, often
contradictory, but nevertheless essential in the reality.
This thesis, composed of three parts, introduces new models and algorithms for
designing WMNs from scratch.
The first part is devoted to the simultaneous optimization of two equally important
objectives: cost and network performance in terms of throughput. Three bi-objective models
which differ mainly by the approach used to maximize network performance are proposed,
solved and compared.
The second part deals with the problem of gateways placement, given its impact on
network performance and scalability. The concept of hop constraints is introduced into the
network design to reduce the transmission delay. A novel algorithm based on a clustering
approach is also proposed to find the strategic positions of gateways that support network
scalability and increase its performance without significantly increasing the cost of installation.
The final section addresses the problem of reliability in the presence of single failures.
Allowing the installation of redundant components in the design phase can ensure reliable
communications, but at the expense of cost and network performance. A new algorithm is
developed based on the theoretical approach of "ear decomposition" to install the minimum
number of additional routers to tolerate single failures.
In order to solve the proposed models for real-size networks, an evolutionary algorithm
(meta-heuristics), inspired from nature, is developed. Finally, the proposed models and
methods have been evaluated through empirical and discrete events based simulations
Machine learning assisted optimization with applications to diesel engine optimization with the particle swarm optimization algorithm
A novel approach to incorporating Machine Learning into optimization routines is presented. An approach which combines the benefits of ML, optimization, and meta-model searching is developed and tested on a multi-modal test problem; a modified Rastragin\u27s function. An enhanced Particle Swarm Optimization method was derived from the initial testing. Optimization of a diesel engine was carried out using the modified algorithm demonstrating an improvement of 83% compared with the unmodified PSO algorithm. Additionally, an approach to enhancing the training of ML models by leveraging Virtual Sensing as an alternative to standard multi-layer neural networks is presented. Substantial gains were made in the prediction of Particulate matter, reducing the MMSE by 50% and improving the correlation R^2 from 0.84 to 0.98. Improvements were made in models of PM, NOx, HC, CO, and Fuel Consumption using the method, while training times and convergence reliability were simultaneously improved over the traditional approach