Dissertations / Theses on the topic 'Approximation algorithms; resource allocation; optimization'
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Chakrabarty, Deeparnab. "Algorithmic aspects of connectivity, allocation and design problems." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/24659.
Full textCommittee Chair: Vazirani, Vijay; Committee Member: Cook, William; Committee Member: Kalai, Adam; Committee Member: Tetali, Prasad; Committee Member: Thomas, Robin
Tripathi, Pushkar. "Allocation problems with partial information." Diss., Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/44789.
Full textKibria, Mirza Golam. "Radio Resource Allocation Optimization for Cellular Wireless Networks." 京都大学 (Kyoto University), 2014. http://hdl.handle.net/2433/189689.
Full textBayrak, Ahmet Engin. "Optimization Algorithms For Resource Allocation Problem Of Air Tasking Order Preparation." Master's thesis, METU, 2010. http://etd.lib.metu.edu.tr/upload/12612325/index.pdf.
Full textcomputer support became inevitable for optimizing the resource management in air force operations. In this thesis, we study different optimization approaches for resource allocation problem of ATO preparation and analyze their performance. We proposed a genetic algorithm formulation with customized encoding, crossover and fitness calculation mechanisms by using the domain knowledge. A linear programming formulation of the problem is developed by integer decision variables and it is used for effectivity and efficiency analysis of genetic algorithm formulations.
Salazar, Javier. "Resource allocation optimization algorithms for infrastructure as a service in cloud computing." Thesis, Sorbonne Paris Cité, 2016. http://www.theses.fr/2016USPCB074.
Full textThe cloud architecture offers on-demand computing, storage and applications. Within this structure, Cloud Providers (CPs) not only administer infrastructure resources but also directly benefit from leasing them. In this thesis, we propose three optimization models to assist CPs reduce the costs incurred in the resource allocation process when serving users’ demands. Implementing the proposed models will not only increase the CP’s revenue but will also enhance the quality of the services offered, benefiting all parties. We focus on Infrastructure as a Service (IaaS) resources which constitute the physical infrastructure of the cloud and are contained in datacenters (DCs). Following existing research in DC design and cloud computing applications, we propose the implementation of smaller DCs (Edge DCs) be located close to end users as an alternative to large centralized DCs. Lastly, we use the Column Generation optimization technique to handle large scale optimization models efficiently. The proposed formulation optimizes both the communications and information technology resources in a single phase to serve IaaS requests. Based on this formulation, we also propose a second model that includes QoS guarantees under the same Infrastructure as a Service resource allocation perspective, to provide different solutions to diverse aspects of the resource allocation problem such as cost and delay reduction while providing different levels of service. Additionally, we consider the multimedia cloud computing scenario. When Edge DCs architecture is applied to this scenario it results in the creation of the Multimedia Edge Cloud (MEC) architecture. In this context we propose a resource allocation approach to help with the placement of these DCs to reduce communication related problems such as jitter and latency. We also propose the implementation of optical fiber network technologies to enhance communication between DCs. Several studies can be found proposing new methods to improve data transmission and performance. For this study, we decided to implement Wavelength Division Multiplexing (WDM) to strengthen the link usage and light-paths and, by doing so, group different signals over the same wavelength. Using a realistic simulation environment, we evaluate the efficiency of the approaches proposed in this thesis using a scenario specifically designed for the DCs, comparing them with different benchmarks and also simulating the effect of the optical formulation on the network performance. The numerical results obtained show that by using the proposed models, a CP can efficiently reduce allocation costs while maintaining satisfactory request acceptance and QoS ratios
Ali, Syed Hussain. "Cross layer scheduling and resource allocation algorithms for cellular wireless networks." Thesis, University of British Columbia, 2008. http://hdl.handle.net/2429/2722.
Full textShashika, Manosha Kapuruhamy Badalge (). "Convex optimization based resource allocation in multi-antenna systems." Doctoral thesis, Oulun yliopisto, 2017. http://urn.fi/urn:isbn:9789526217499.
Full textTiivistelmä Monen antennin käyttö on perusvaatimus tulevissa langattomissa verkoissa, koska se auttaa lisäämään matkaviestinyhteyksien luotettavuutta ja spektritehokkuutta. Tässä väitöskirjassa tutkitaan konveksiin optimointiin perustuvia radioresurssien allokointimenetelmiä moniantennijärjestelmien alalinkin suunnassa. Ensiksi on käsitelty pääsynvalvonnan ongelmaa alalinkin suuntaan monen solun moni-tulo yksi-lähtö (MISO) -verkoissa. Tavoitteena on maksimoida hyväksyttyjen käyttäjien määrä, kun hyväksytyille käyttäjille on asetettu signaali-häiriö-kohinasuhteen (SINR) rajoitus, ja tukiasemille lähetystehon rajoitus. Pääsynvalvonnan ongelma on muotoiltu ℓ0-minimointiongelmana, jonka tiedetään olevan kombinatorinen, NP-vaikea ongelma. Ongelman ratkaisemiseksi on ehdotettu keskitettyjä ja hajautettuja algoritmeja. Keskitetty optimointialgoritmi perustuu sekventiaaliseen konveksiin optimointiin. Hajautettu algoritmi pohjautuu konsensusoptimointimenetelmään ja sekventiaaliseen konveksiin optimointiin. Ehdotettujen pääsynvalvonta-algoritmien on numeerisesti osoitettu saavuttavan lähes optimaalinen suorituskyky. Lisäksi pääsynvalvontaongelma on laajennettu takaamaan pitkän aikavälin oikeudenmukaisuus käyttäjien välillä. Työssä käytetään erilaisia määritelmiä oikeudenmukaisuuden takaamiseen, ja ehdotetaan dynaamisia algoritmeja pohjautuen Lyapunov-optimointiin. Tulokset osoittavat, että ehdotetuilla algoritmeilla taataan käyttäjien välinen oikeudenmukaisuus. Tämän jälkeen käsitellään heterogeenisen langattoman MISO-verkon pääsynvalvonnan ongelmaa. Edellä ehdotettuja keskitettyjä ja hajautettuja algoritmeja on muokattu tämän ongelman ratkaisemiseksi. Työssä osoitetaan numeerisesti, että sekä keskitetyllä että hajautetulla algoritmilla saavutetaan lähes optimaalinen suorituskyky. Lopuksi on laadittu algoritmi, jolla löydetään kaikki saavutettavissa olevat teho-datanopeusparit heterogeenisessä langattomassa moni-tulo moni-lähtö (MIMO) -verkossa. Verkko koostuu yhdestä makrosolusta ja useasta piensolusta. Piensolutukiasemista makrokäyttäjiin kohdistuvan häiriön teho on pidetty tietyn rajan alapuolella. Kaikkien saavutettavien teho-datanopeusparien löytämiseksi on laadittu kaksiulotteinen vektorioptimointiongelma, jossa maksimoidaan summadatanopeus pyrkien minimoimaan kokonaisteho, kun enimmäisteholle ja häiriökynnykselle on asetettu rajoitukset. Tämän ongelman tiedetään olevan NP-vaikea. Ongelman ratkaisemiseksi käytetään painotetun summadatanopeuden maksimointiongelman, ja painotetun keskineliövirheen minimointiongelman välistä suhdetta. Ehdotettua algoritmia käytettiin arvioimaan häiriörajoitusten ja saman kanavan käyttöönoton vaikutusta heterogeenisessä langattomassa verkossa
Mharsi, Niezi. "Cloud-Radio Access Networks : design, optimization and algorithms." Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLT043/document.
Full textCloud Radio Access Network (C-RAN) has been proposed as a promising architecture to meet the exponential growth in data traffic demands and to overcome the challenges of next generation mobile networks (5G). The main concept of C-RAN is to decouple the BaseBand Units (BBU) and the Remote Radio Heads (RRH), and place the BBUs in common edge data centers (BBU pools) for centralized processing. This gives a number of benefits in terms of cost savings, network capacity improvement and resource utilization gains. However, network operators need to investigate scalable and cost-efficient algorithms for resource allocation problems to enable and facilitate the deployment of C-RAN architecture. Most of these problems are very complex and thus very hard to solve. Hence, we use combinatorial optimization which provides powerful tools to efficiently address these problems.One of the key issues in the deployment of C-RAN is finding the optimal assignment of RRHs (or antennas) to edge data centers (BBUs) when jointly optimizing the fronthaul latency and resource consumption. We model this problem by a mathematical formulation based on an Integer Linear Programming (ILP) approach to provide the optimal strategies for the RRH-BBU assignment problem and we propose also low-complexity heuristic algorithms to rapidly reach good solutions for large problem instances. The optimal RRH-BBU assignment reduces the expected latency and offers resource utilization gains. Such gains can only be achieved when reducing the inter-cell interference caused by the dense deployment of cell sites. We propose an exact mathematical formulation based on Branch-and-Cut methods that enables to consolidate and re-optimize the antennas radii in order to jointly minimize inter-cell interference and guarantee a full network coverage in C-RAN. In addition to the increase of inter-cell interference, the high density of cells in C-RAN increases the amount of baseband processing as well as the amount of data traffic demands between antennas and centralized data centers when strong latency requirements on fronthaul network should be met. Therefore, we discuss in the third part of this thesis how to determine the optimal placement of BBU functions when considering 3GPP split option to find optimal tradeoffs between benefits of centralization in C-RAN and transport requirements. We propose exact and heuristic algorithms based on combinatorial optimization techniques to rapidly provide optimal or near-optimal solutions even for large network sizes
Lenharth, Andrew D. "Algorithms for stable allocations in distributed real-time resource management systems." Ohio : Ohio University, 2004. http://www.ohiolink.edu/etd/view.cgi?ohiou1102697777.
Full textMorimoto, Naoyuki. "Design and Analysis of Algorithms for Graph Exploration and Resource Allocation Problems and Their Application to Energy Management." 京都大学 (Kyoto University), 2014. http://hdl.handle.net/2433/189687.
Full textHasan, Cengis. "Optimization of resource allocation in small cells networks : A green networking approach." Phd thesis, INSA de Lyon, 2013. http://tel.archives-ouvertes.fr/tel-01015735.
Full textAlinia, Bahram. "Optimal resource allocation strategies for electric vehicles in smart grids." Thesis, Evry, Institut national des télécommunications, 2018. http://www.theses.fr/2018TELE0012/document.
Full textWith the increased environmental concerns related to carbon emission, and rapid drop in battery prices (e.g., 35% drop in 2017), the market share of Electric Vehicles (EVs) is rapidly growing. The growing number of EVs along with the unprecedented advances in battery capacity and technology results in drastic increase in the total energy demand of EVs. This large charging demand makes the EV charging scheduling problem challenging. The critical challenge is the need for online solution design since in practical scenario the scheduler has no information of future arrivals of EVs in a time-coupled underlying problem. This thesis studies online EV scheduling problem and provides three main contributions. First, we demonstrate that the classical problem of online scheduling of deadlinesensitive jobs with partial values is similar to the EV scheduling problem and study the extension to EV charging scheduling by taking into account the processing rate limit of jobs as an additional constraint to the original problem. The problem lies in the category of time-coupled online scheduling problems without availability of future information. Using competitive ratio, as a well-established performance metric, two online algorithms, both of which are shown to be (2 − 1/U)-competitive are proposed, where U is the maximum scarcity level, a parameter that indicates demand-to-supply ratio. Second, we formulate a social welfare maximization problem for EV charging scheduling with charging capacity constraint. We devise charging scheduling algorithms that not only work in online scenario, but also they address the following two key challenges: (i) to provide on-arrival commitment; respecting the capacity constraint may hinder fulfilling charging requirement of deadline-constrained EVs entirely. Therefore, committing a guaranteed charging amount upon arrival of each EV is highly required; (ii) to guarantee (group)-strategy-proofness as a salient feature to promote EVs to reveal their true type and do not collude with other EVs. Third, we tackle online scheduling of EVs in an adaptive charging network (ACN) with local and global peak constraints. Two alternatives in resource-limited scenarios are to maximize the social welfare by partially charging the EVs (fractional model) or selecting a subset of EVs and fully charge them (integral model). For the fractional model, both offline and online algorithms are devised. We prove that the offline algorithm is optimal. We prove the online algorithm achieves a competitive ratio of 2. The integral model, however, is more challenging since the underlying problem is NP-hard due to 0/1 selection criteria of EVs. Hence, efficient solution design is challenging even in offline setting. We devise a low-complexity primal-dual scheduling algorithm that achieves a bounded approximation ratio. Built upon the offline approximate algorithm, we propose an online algorithm and analyze its competitive ratio in special cases
Lunday, Brian Joseph. "Resource Allocation on Networks: Nested Event Tree Optimization, Network Interdiction, and Game Theoretic Methods." Diss., Virginia Tech, 2010. http://hdl.handle.net/10919/77323.
Full textPh. D.
Houidi, Omar. "Algorithms for Virtual Network Functions chaining." Electronic Thesis or Diss., Institut polytechnique de Paris, 2020. http://www.theses.fr/2020IPPAS005.
Full textNetwork Function Virtualization (NFV) is an innovative emerging concept that decouples network functions (such as firewalls, DNS, NATs, load balancers, etc.) from dedicated hardware devices (the traditional expensive middleboxes). This decoupling enables hosting of network services, known as Virtualized Network Functions (VNFs), on commodity hardware (such as switches or servers) and thus facilitates and accelerates service deployment and management by providers, improves flexibility, leads to efficient and scalable resource usage, and reduces costs. This paradigm is a major turning point in the evolution of networking, as it introduces high expectations for enhanced economical network services, as well as major technical challenges.One of the main technical challenges in this domain is the optimal placement of the VNFs within the hosting infrastructures. This placement has a critical impact on the performance of the network, as well as on its reliability and operation cost. The VNF Placement and Chaining Problem is NP-Hard and there is a need for placement approaches that can scale with problem size and find good solutions in acceptable times. The overarching goal of this thesis is to enable dynamic virtual network resources provisioning to deal with demand fluctuation during the virtual network lifetime, and to enhance the substrate resource usage. Reserving a fixed amount of resources is inefficient to satisfy the VNF resource requirements. To cope with these problems, we propose dynamic resource management strategies.In this thesis, both exact and heuristic algorithms are designed and evaluated in terms of optimality, complexity, ability to scale, and compared with the state of the art. Elastic mechanisms and scaling algorithms are first presented to improve adaptation and deployment of virtualized network functions in NFV infrastructures to support increasing demand while increasing provider's revenue. Since network providers not only need to control, classify and steer user and application traffic flows in their dedicated slices but also want to extend their already acquired and operational virtual networks or slices with additional service graphs, the thesis proposes extension algorithms of already hosted network functions graphs without disrupting initially deployed and active service instances. The proposed algorithms extend already deployed network services and functions graphs to respond to new demands while taking into account the constraint of minimizing the impact on the original service graphs. The extension algorithms are particularly useful and suitable for situations where already deployed graphs need to be enhanced with new features and properties (adding new functions) and modified to react to degradation and attacks such as removing a fraction of the graph and replacing with new complex and composed functions into more capable and uncompromised graphs.The thesis also addresses the VNF placement and chaining problem in an online and in a batch mode to improve performance in terms of longer time reward. An enhanced Reinforcement Learning-based approach is also proposed to improve the long term reward beyond what the previous methods can achieve. This is analyzed and realized for a load balancing objective but can be adjusted for other criteria
Syed, Muhammad Fahad. "Various resource allocation and optimization strategies for high bit rate communications on power lines." Phd thesis, INSA de Rennes, 2010. http://tel.archives-ouvertes.fr/tel-00480261.
Full textIndrakanti, Saratchandra. "Computational Methods for Vulnerability Analysis and Resource Allocation in Public Health Emergencies." Thesis, University of North Texas, 2015. https://digital.library.unt.edu/ark:/67531/metadc804902/.
Full textLiu, Qingyu. "Delay-Aware Multi-Path Routing in a Multi-Hop Network: Algorithms and Applications." Diss., Virginia Tech, 2019. http://hdl.handle.net/10919/90405.
Full textDoctor of Philosophy
We consider a network modeled as a directed graph, where it takes time for data to traverse each link in the network. It models many critical applications both in the communication area and in the transportation field. For example, both the European education network and the US national highway network can be modeled as directed graphs. We consider a scenario where a source node is required to send multiple (a set of) data packets to a destination node through the network as fast as possible, possibly using multiple source-to-destination paths. In this dissertation we study four problems all of which try to figure out routing solutions to send the set of data packets, with an objective of minimizing experienced travel time or subject to travel time constraints. Although all of our four problems are NP-hard, we design approximation algorithms to solve them and obtain solutions with theoretically bounded gaps as compared to the optimal. The first three problems are in the communication area, and the last problem is in the transportation field. We claim the following specific contributions. Minimize maximum delay and average delay. First, we consider the setting of simultaneously minimizing the average travel time and the worst (largest) travel time of sending the set of data packets from source to destination. Existing results say that the two metrics of travel time cannot be minimized to be both within bounded-ratio gaps to the optimal. As a comparison, we design three different routing solutions, each of which can minimize the two metrics of travel time simultaneously within a constant bounded ratio-gap to the optimal, but at a cost of only delivering a portion of the data. Minimize Age-of-Information (AoI). Second, we consider the problem of minimizing a newly proposed travel-time-sensitive performance metric, i.e., AoI, which is the elapsed time since the generation of the last received data. Our AoI study differs from existing ones in that we are the first to consider a set of data and multi-path routing. We develop both an optimal algorithm with a pseudo-polynomial time complexity and an approximation framework with a polynomial time complexity. Maximize network utility. Third, we consider a more general setting with multiple source destination pairs. Each source incurs a utility that is a function of the experienced travel time or the achieved throughput to send data to its destination. Our objective is to maximize the aggregate utility under throughput requirements and travel time constraints. We develop a polynomial-time approximation algorithm, at the cost of violating constraints by up to constant-ratios. It is non-trivial to design such algorithms, as we prove that it is NPcomplete either to construct an optimal solution under relaxed delay constraints or relaxed throughput requirements, or to figure out a feasible solution with all constraints satisfied. Minimize fuel consumption for a heavy truck to timely fulfill multiple transportation tasks. Finally, we consider a truck and multiple transportation tasks in order, where each task requires the truck to pick up cargoes at a source timely, and deliver them to a destination timely. The need of coordinating task execution times is a new challenging design space for saving fuel in our multi-task setting, and it differentiates our study from existing ones under the single-task setting. We design an efficient heuristic. We characterize conditions under which the solution of our heuristic must be optimal, and further prove its performance gap as compared to the optimal in case the conditions are not met.
Chen, Xue. "Efficient Device to Device Communication Underlaying Heterogeneous Networks." DigitalCommons@USU, 2016. https://digitalcommons.usu.edu/etd/4673.
Full textOliveira, Rodrigo Ruas. "Toward cost-efficient Dos-resilient virtual networks with ORE : opportunistic resilience embedding." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2013. http://hdl.handle.net/10183/71908.
Full textRecently, the Internet’s success has prevented the dissemination of novel networking architectures and protocols. Specifically, any modification to the core of the network requires agreement among many different parties. To address this situation, Network Virtualization has been proposed as a diversifying attribute for the Internet. This paradigm promotes the development of new architectures and protocols by enabling the creation of multiple virtual networks on top of a same physical substrate. In addition, applications running over the same physical network can be isolated from each other, thus allowing them to coexist independently. One of the main advantages of this paradigm is the use of isolation to limit the scope of attacks. This can be achieved by creating different, isolated virtual networks for each task, so traffic from one virtual network does not interfere with the others. However, routers and links are still vulnerable to attacks and failures on the underlying network. Particularly, should a physical link be compromised, all embedded virtual links will be affected. Previous work tackled this problem with two main strategies: using backup resources to protect against disruptions; or live migration to relocate a compromised virtual resource. Both strategies have drawbacks: backup resources tend to be expensive for the infrastructure provider, while live migration may leave virtual networks inoperable during the recovery period. This dissertation presents ORE (Opportunistic Resilience Embedding), a novel embedding approach for protecting virtual links against substrate network disruptions. ORE’s design is two-folded: while a proactive strategy embeds virtual links into multiple substrate paths in order to mitigate the initial impact of a disruption, a reactive one attempts to recover any capacity affected by an underlying disruption. Both strategies are modeled as optimization problems. Additionally, since the embedding problem is NP-Hard, ORE uses a Simulated Annealing-based meta-heuristic to solve it efficiently. Numerical results show that ORE can provide resilience to disruptions at a lower cost.
Campos, Ciro Guillermo. "Développement de méthodes d'ordonnancement efficaces et appliquées dans un système de production mécanique." Thesis, Troyes, 2015. http://www.theses.fr/2015TROY0035/document.
Full textThe continuous evolution of manufacturing environments and the growing of customer needings, leads to a faster and more efficient production process that controls an increasing number of parameters. This thesis is focused on the development of decision making methods in order to improve the production scheduling. The industrial partner (Norelem) produces standardized mechanical elements, so many different resource constraints (humans and tools) are presented in its workshop.We study an open shop scheduling problem where one job can follow multiple production sequences because there is no fixed production sequence and the objective function is to minimize the total flow time. In addition, multi-skilled personnel assignment and tool’s availability constraints are involved.Mathematical models: linear and non-linear formulations have been developed to describe the problem. Knowing the exact method limitations in terms of instance sizes because of the duration, heuristics methods have been proposed and compared. Besides that, the multi-objective optimization was exposed to deal with three objectives as total flow time minimization and workload balancing concerning both, humans and machines.The efficiency of these methods was proved by several theoretical instance tests and the application on the real industrial case
Valdivia, Nereida Celina Llerena. "Roteamento de tráfego e alocação de recursos em redes ópticas WDM com base em economia de energia." Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/18/18155/tde-06012015-161005/.
Full textThe growth of data traffic in telecommunication networks has increased energy consumption and hence increased CO2 emissions, with harmful effects on the environment. Thus, energy saving becomes a key and a differential factor when planning telecommunication networks. In order to guarantee availability and reliability, core networks have redundant architecture and are designed to support peak-hour traffic demand. Networks with dedicated path protection (DPP) mechanisms provide alternative paths for each connection request. Network elements supporting these paths are in active state (consuming energy), although most of the time they dont carry traffic. One technique to decrease energy waste is by adaptive real traffic routing using sleep mode (a low energy consumption state which is able to rapidly change to an active state). Thus, traffic is routed in order to maximize the amount of network components used by protection paths, which can be set in sleep mode. In this work, European Cost239, American UsNet and Brazilian Ipê networks were used in computational simulations. We addressed the energy saving problem in WDM networks with DPP through four routing strategies, each with different goals. The Shorthest Path-Dedicated Path Protection (SP-DPP) technique uses shortest path for routing, Energy Aware-Dedicated Path Protection (EA-DPP) allocates demands in active links, Energy Aware-Dedicated Path Protection with Mixing (EA-DPP-MixS) prevents primary paths to be formed by links that are already part of the protection paths and Energy Aware-Dedicated Path Protection with Differentation (EA-DPP-Dif) prevents mixing primary and protection paths through the same link. We observe that EA-DPP-Dif efficiently saved energy, however blocking probability has increased. EA-DPP-MixS reduced blocking rather than saved energy. At least, SP-DPP and EA-DPP are less efficient in reducing energy consumption. Hence, we propose a wider resource search routing, the in-depth routing, using each of these strategies. Thus, EA-DPP-Dif-In-depth decreased blocking probability while maintaining energy saving through sleep mode. In this work, we analyze the strategies performance for each network and evaluate the impact of energy saved on the blocking probability. Our in-depth routing strategy reduced the energy consumption up to 50%, decreasing blocking probability. However, the results are directly related with the network load and the specific properties of each network topology.
Allybokus, Zaïd. "Algorithmes distribués dédiés au calcul de l’allocation alpha-équitable en temps réel dans les réseaux SDN." Thesis, Université Côte d'Azur (ComUE), 2019. http://www.theses.fr/2019AZUR4038.
Full textIn this dissertation, we deal with the design of algorithms to tackle the α-fair resource allocation problem in real-time and distributed Software-Defined Networks (SDN). First, we define three major requirements that picture the challenges of real-time algorithms implementable in modern distributed SDN controllers. Those challenges are the ability to provide feasible resource allocations at all times, good transient solutions in terms of optimality gap that converge in an acceptable number of inter-controller communication rounds, and their ability of being massively parallelized independently of the network architecture. We use the Alternating Directions Method of Multipliers to design an algorithm that simultaneously, and unprecedentedly, tackles the three challenges. Motivated by a first study of the structural properties of the α-fair model, where we derive a lower bound on the optimal solution, we tune the penalty parameter of the augmented Lagrangian of the problem in order to optimize the algorithm’s performance. We show that the algorithm can function in real-time when the traffic requirements can vary more or less abruptly. The variation of the traffic requirements are modeled by real-time varying coefficients of the optimization model that is solved on-the-fly and may represent various prioritization policies of the traffic (payment, traffic type, number of connections within a tunnel, etc). Then, we describe how to extend the algorithm to real world use cases with limited modifications to cope with multi-path load balancing and online adjustments. Furthermore, we address the problem of α-fairness when the environment is uncertain and the available amount of resources over the network links is known only through general density functions. The main focus there is, instead of feasibility, the notion of safety. We design a heuristic that polishes an outer relaxation of the problem, based on the sensitivity analysis of the static problem. In general, we are able to provide a safe and acceptably efficient solution by solving several static problems
Liao, Kewen. "Approximation algorithms for resource allocation optimization." Thesis, 2014. http://hdl.handle.net/2440/85975.
Full textThesis (Ph.D.) -- University of Adelaide, School of Computer Science, 2014
Wang, Chuan-Ren, and 王傳仁. "Application of Multi-objective Genetic Algorithms for Virtual Resource Allocation Scheduling Optimization." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/39187541474918647888.
Full text國立高雄第一科技大學
系統資訊與控制研究所
100
In order to satisfy given SLA (service level agreements) as end-to-end QoS (quality of service) requirements in cloud computing environments by users, consequently, server requirements of IaaS (Infrastructure as a Service) rise up rapidly among cloud service. They lead to establish cost enormously. The performance of virtual technology is improved. Hence, using virtual technology can be solved efficiently above situation. Also for the sake of gratifying with the constraint on SLA (service level agreements) as end-to-end QoS (quality of service) requirements, we must consider the cost and time of execution at the same time. So we present a method of Multi-objective Genetic Algorithm to solve this problem.
"Distributed stochastic algorithms for communication networks." Thesis, 2010. http://library.cuhk.edu.hk/record=b6075262.
Full textFirst, we consider instances of the designed Markov chain over resource allocation algorithms. We focus on the convergence issues. We find several examples such that the related convergence results can be applied directly. These examples include optimal path (or tree) selection for wireline networks, optimal neighboring selection for peer-to-peer networks, and optimal channel (or power) assignment for wireless local area networks.
In this thesis, we first review Markov approximation framework and further develop this framework by studying convergence properties of distributed algorithms. These system-wide algorithms consist of the designed Markov chain and resource allocation algorithms. We concentrate on two general scenarios: the designed Markov chain over resource allocation algorithms and resource allocation algorithms over the designed Markov chain. With imprecise measurements of network parameters and without the time-scale separation assumption, we prove convergence to near-optimal solutions for both scenarios under mild conditions. Then we apply Markov approximation framework and associated convergence results to various combinatorial network optimization problems.
Second, we consider instances of resource allocation algorithms over the designed Markov chain. We focus on the system-wide performances. Two instances are investigated: cross-layer optimization for wireless networks with deterministic channel model and wireless networks with network coding. For both instances, guided by Markov approximation framework, we design distributed schemes to achieve maximum utilities. These schemes include primal-dual flow control algorithms, Markov chain based scheduling algorithms, and routing (or network coding) algorithms. Under time-dependent step sizes and update intervals, we show that these distributed schemes converge to the optimal solutions with probability one. Further, under constant step sizes and constant update intervals, we prove that these distributed schemes also converge to a bounded neighborhood of optimal solutions with probability one. These analytical results are validated by numerical results as well.
Shao, Ziyu.
Adviser: Shou Yen Robert Li.
Source: Dissertation Abstracts International, Volume: 73-03, Section: B, page: .
Thesis (Ph.D.)--Chinese University of Hong Kong, 2010.
Includes bibliographical references (leaves 134-140).
Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web.
Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [201-] System requirements: Adobe Acrobat Reader. Available via World Wide Web.
Abstract also in Chinese.
"Optimal Resource Allocation in Social and Critical Infrastructure Networks." Doctoral diss., 2016. http://hdl.handle.net/2286/R.I.40712.
Full textDissertation/Thesis
Doctoral Dissertation Computer Science 2016
Liao, Ying-Tzong, and 廖英宗. "A Study of Global Optimization Algorithms for Back Propagation - A Case Study of Freeway Incident Resource Allocation." Thesis, 2000. http://ndltd.ncl.edu.tw/handle/48289535504478894579.
Full text淡江大學
運輸管理學系
88
Due to the significant learning ability, the Neural Network algorithm has been applied to all kinds of domains recently. However, the existence of local optimal points, using global searching algorithm to improve the performance for Back Propagation Network (BPN) becomes a common research topic. The investigation declared that Threshold Accepting (TA), Great Deluge Algorithm (GDA) and Simulated Annealing (SA) have better performance in solving problems with local optimal points. So, this study employs architecture of Neural Network as the kernel and combines with global optimization search algorithm to improve the performance of traditional BPN algorithm. Regarding the allocation process of rescue resources, the quality of current resource assignment processes is depended upon dispatcher’s work experiences. In usual, the assignments are completed by hand and responses must be made right away, so it's easy to happen the mismatches of the resource allocation in turn the needs of extra efforts for re-allocation. Although there is no any application instance of BPN in Taiwan now, using BPN can easily establish the mapping relations between accident information and the work load for the resource allocation. From this study, we can draw a few significant results as follows. 1.With fewer nodes, TA, GDA and SA have better performance in convergence for problem learning mechanism than the traditional Neural Network algorithm. 2.For single event, the modified algorithm has accuracy in average more than 80%. 3.To cope with the local optimal points and improve inferior solution, the global optimal search algorithm can improve the quality of convergent solution and save computation time. 4.Due to the ineffective incident management procedures, the needs to develop an automatic identification surveillance system using self learning BNP algorithm for incident management are the urgent task.
Skowron, Piotr. "Resource allocation in selfish and cooperative distributed systems." Doctoral thesis, 2014.
Find full textW poniższej rozprawie badamy algorytmy zarządzania zasobami w systemach rozproszonych. Przedstawiamy kompleksowe spojrzenie na tę tematykę: rozważamy różne systemy---od ogólnych, abstrakcyjnych modeli, przez bardziej konkretne, dedykowane modele, po rzeczywiste systemy rozproszone. Rozważane systemy różnią się specyfiką problemów zarządzania zasobami oraz metodologią, którą jest dla tych problemów najbardziej adekwatna.Efektywne zarządzanie zasobami w systemach rozproszonych jest problemem o fundamentalnym znaczeniu. Systemy komputerowe wymagają dobrych mechanizmów zarządzania zasobami aby zapewnić odpowiednią jakość usług dla użytkowników. Również w naszym codziennym życiu często uczestniczymy w mechanizmach zarządzania zasobami. Przykłady takich mechanizmów to między innymi podział tortu na przyjęciu urodzinowym, czy referenda, a nawet wybory parlamentarne (w tym przypadku możemy utożsamiać kandydatów startujących w wyborach z zasobami).W pierwszej części rozprawy rozważamy ogólny, abstrakcyjny model który opisuje problem wyboru podzbioru pewnych obiektów, które następnie będą współdzielone przez grupę użytkowników. Ten model jest bardzo ogólny ponieważ nie specyfikujemy kim (lub czym) dokładnie jest użytkownik i czym dokładnie są owe obiekty. W rezultacie, rozwiązania oparte o ten model możemy zaaplikować do wielu rzeczywistych problemów, takich jak przydział studentów, w oparciu o ich preferencje, do uniwersyteckich kursów, czy znajdowanie właściwych rekomendacji. Takie rekomendacje mogą dotyczyć, na przykład, wyboru zbioru filmów dostępnych na pokładzie samolotu. Nasze algorytmy znajdują takżę zastosowanie w znajdowaniu proporcjonalnej reprezentacji dla grupy ludzi, czyli np. aby znaleźć zwycięzców w niektórych nowoczesnych systemach wyborów parlamentarnych. W niniejszej rozprawie analizujemy wiele specyficznych wariantów tego ogólnego zagadnienia.W drugiej częsci rozprawy rozważamy bardziej specyficzne modele opisujące systemy komputerowe. W tych modelach pojawiają się nowe elementy, takie jak zadania, procesory, czy sieć komputerowa. Każdy z tych elementów może być opisany przez zbiór parametrów: zadania mają swoje czasy powstania, wymagania zasobów, czy czasy wykonania. Długość trwania zadania może ponadto zależeć od rodzaju procesora na którym zadanie zostało uruchomione: procesory mogą być identyczne lub heterogeniczne. Połączenia sieciowe mogą być opisane przez przepustowość lub/i latencję komunikacji. Naturalnie w tych modelach zadajemy również bardziej specyficzne pytania. Pytamy jak uszeregować zadania, aby zminimalizować ich zagregowany czas zakonczenia. Specyficzne warianty tego pytania róznią się w zależności od metody agregacji oraz w zależności od cech charakterystycznych wybranych elementów modelu. W rozważanych modelach badamy złożoność obliczeniową różnych wariantów problemu szeregowania, w szczególności pokazując efektywne algorytmy do optymalizacji uszeregowania zadań. W tej części rozprawy analizujemy również inne cechy naszych algorytmów, takie jak odporność na błędy czy (teorio-growa) stabilność.W ostatniej części rozprawy rozważamy problemy zarządzania zasobami w rzeczywistych, złożonych, komputerowych systemach rozproszonych. Rozważamy dwa rzeczywiste systemy przechowywania danych: HYDRAstor, który jest komercyjnym, rozproszonym, skalowalnym systemem przechowywania danych, oraz naszą prototypową implemenację systemu do tworzenia kopii zapasowych danych, opartego o architekturę P2P. Wyjaśniamy czym różni się projektowanie mechanizmów zarządzania zasobami dla takich systemów od poprzednio rozważanych przypadków. W tej części prezentujemy relatywnie bardziej złożone mechanizmy zarządzania zasobami: mechanizmy te składają się z wielu elementów, a nawet z wielu podsystemów zarządzania zasobami. Co więcej takie podsystemy mogą mieć czasami sprzeczne ze sobą cele.
Xia, Qiufen. "Cost-Effective Resource Allocation and Throughput Maximization in Mobile Cloudlets and Distributed Clouds." Phd thesis, 2017. http://hdl.handle.net/1885/117056.
Full textΦραίμης, Ιωάννης. "Τεχνικές βελτιστοποίησης της ποιότητας των παρεχομένων υπηρεσιών (QoS) με έλεγχο κρίσιμων ηλεκτρικών και ηλεκτρομαγνητικών παραμέτρων στα σύγχρονα ασύρματα τηλεπικοινωνιακά συστήματα." Thesis, 2012. http://hdl.handle.net/10889/5546.
Full textThis doctoral thesis proposes QoS optimization techniques in modern wireless telecommunication systems, whereby orthogonal frequency division multiple access and code division are used. The proposed techniques are iterative resource allocation algorithms which are mainly suitable for the downlink of wireless networks. The minimum required level of data rate, the bit error rate and the minimum number of resources per user are considered as quality of service parameters. The validation of the proposed techniques is done through the performance of performance metrics like the : the quality of service violation probability, the system fairness index, the cell-edge data rate and the cell capacity. Statistical data are required which are collected through extensive simulation