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Multilayer optimization in radio resource allocation for the packet transmission in wireless networks

Nascimento, Alberto Jesus de
Fonte: Universidade da Madeira Publicador: Universidade da Madeira
Tipo: Tese de Doutorado
Publicado em //2009 ENG
Relevância na Pesquisa
66.38%
In the last decade mobile wireless communications have witnessed an explosive growth in the user’s penetration rate and their widespread deployment around the globe. It is expected that this tendency will continue to increase with the convergence of fixed Internet wired networks with mobile ones and with the evolution to the full IP architecture paradigm. Therefore mobile wireless communications will be of paramount importance on the development of the information society of the near future. In particular a research topic of particular relevance in telecommunications nowadays is related to the design and implementation of mobile communication systems of 4th generation. 4G networks will be characterized by the support of multiple radio access technologies in a core network fully compliant with the Internet Protocol (all IP paradigm). Such networks will sustain the stringent quality of service (QoS) requirements and the expected high data rates from the type of multimedia applications to be available in the near future. The approach followed in the design and implementation of the mobile wireless networks of current generation (2G and 3G) has been the stratification of the architecture into a communication protocol model composed by a set of layers...

Algoritmo distribuído para alocação de múltiplos recursos em ambientes distribuídos.; Distributed algorithm for multiple resource allocation in a distributed environment.

Ribacionka, Francisco
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 07/06/2013 PT
Relevância na Pesquisa
66.46%
Ao considerar um sistema distribuído composto por um conjunto de servidores, clientes e recursos, que caracterizam ambientes como grades ou nuvens computacionais, que oferecem um grande número de recursos distribuídos como CPUs ou máquinas virtuais, os quais são utilizados conjuntamente por diferentes tipos de aplicações, tem-se a necessidade de se ter uma solução para alocação destes recursos. O apoio à alocação dos recursos fornecidos por tais ambientes deve satisfazer todas as solicitações de recursos das aplicações, e fornecer respostas afirmativas para alocação eficiente de recursos, fazer justiça na alocação no caso de pedidos simultâneos entre vários clientes de recursos e responder em um tempo finito a requisições. Considerando tal contexto de grande escala em sistemas distribuídos, este trabalho propõe um algoritmo distribuído para alocação de recursos. Este algoritmo explora a Lógica Fuzzy sempre que um servidor está impossibilitado de atender a uma solicitação feita por um cliente, encaminhando esta solicitação a um servidor remoto. O algoritmo utiliza o conceito de relógio lógico para garantir justiça no atendimento das solicitações feitas em todos os servidores que compartilham recursos. Este algoritmo segue o modelo distribuído...

Adaptive resource allocation in multimodal activity networks

Tereso, Anabela Pereira; Araújo, Maria Madalena Teixeira de; Elmaghraby, Salah
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica
Publicado em 08/11/2004 ENG
Relevância na Pesquisa
66.38%
In practice, project managers must cope with uncertainty, and must manipulate the allocation of their resources adaptively in order to achieve their ultimate objectives. Yet, treatments of the well-known ‘resource constrained project scheduling problem’ have been deterministic and static, and have addressed mostly unimodal activities. We present an approach to resource allocation under stochastic conditions for multimodal activity networks. Optimization is via dynamic programming, which proves to be demanding computationally. We suggest approximation schemes that do not detract signi…cantly from optimality, but are modest in their computational requirements.

Dynamic resource allocation architecture for IEEE802.16e: Design and performance analysis

Nascimento, A.; Rodriguez, J.; Mumtaz, S.; Gameiro, A.; Politis, C.
Fonte: Springer Publicador: Springer
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
66.38%
Mobile communications has witnessed an exponential increase in the amount of users, services and applications. WiMAX (Worldwide Interoperability for Microwave Access) targets to provide broadband connectivity to wide area coverage, both in fixed and in mobile environments, as well as in the provision of QoS constraints of those applications and services envisioned for Next Generation Networks (NGNs), which results in significant design challenges in the MAC (Medium Access Control) to provide the seamless transport of heterogeneous traffic in a cost-effective manner. This paper proposes a Dynamic Resource Allocation (DRA) architecture for the IEEE802.16e broadband wireless system (also known as Mobile WiMAX) that can provide operators the flexibility to deliver broadband traffic with high spectral efficiency. The proposed DRA architecture framework encompasses scheduler, Link Adaptation (LA), Resource Allocation (RA) and Hybrid Automated Repeat Request (HARQ) functional blocks which interwork seamlessly. The performance of the DRA was evaluated using commonly deployed scheduling policies: Max C/I, Proportional Fair and Round Robin schemes. Simulation results show that the proposed DRA scheme has the capacity to provide enhanced coverage and QoS provisioning for the area networks (WANs)...

Dynamic resource allocation for beyond 3G cellular networks

Huy, D.T.P.; Rodriguez, J.; Gameiro, A.; Tafazolli, R.
Fonte: Universidade de Aveiro Publicador: Universidade de Aveiro
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
66.45%
The Multicarrier CDMA Transmission Techniques for Integrated Broadband Cellular Systems (MATRICE) project addresses a candidate solution for a Beyond 3G (B3G) air-interface based on Multi-Carrier Code Division Multiple Access (MC-CDMA). It investigates dynamic resource allocation strategies at the Medium Access Control (MAC) layer to support the transport of Internet Protocol (IP) packets over the air-interface in a cost effective manner and maximise the cell capacity with a target QoS. A candidate Dynamic Resource Allocation (DRA) protocol architecture is proposed that is based on cross-layer signalling to provide reactive resource allocation according to the fast channel and traffic variations. In-line with B3G expectations, the proposed DRA handles a very large number of users with inherent flexibility and granularity necessary to support heterogeneous traffic, and still with limited complexity. Thanks to the modular architecture of the DRA, various scheduling policies are investigated and compared in terms of capacity and reactivity to the system environment. Simulation results have shown that the MATRICE system has the potential to deliver broadband heterogenous services in a cost-effective manner, and emerge as a propespective candidate air-interface for B3G cellular networks.

Large discreet resource allocation: a hybrid approach based on dea efficiency measurement

Gomes,Eliane Gonçalves; Mello,João Carlos Correia Baptista Soares de; Meza,Lidia Angulo
Fonte: Sociedade Brasileira de Pesquisa Operacional Publicador: Sociedade Brasileira de Pesquisa Operacional
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2008 EN
Relevância na Pesquisa
66.42%
Resource allocation is one of the traditional Operations Research problems. In this paper we propose a hybrid model for resource allocation that uses Data Envelopment Analysis efficiency measures. We use Zero Sum Gains DEA models as the starting point to decrease the computational work for the step-bystep algorithm to allocate integer resources in a DEA context. Our approach is illustrated by a numerical example.

Adaptive Distributed Resource Allocation in Wireless Sensor Networks

Lim, Hock Beng; Lam, Vinh The; Foo, Mao Ching; Zeng, Yulian
Fonte: MIT - Massachusetts Institute of Technology Publicador: MIT - Massachusetts Institute of Technology
Tipo: Artigo de Revista Científica Formato: 480608 bytes; application/pdf
EN
Relevância na Pesquisa
66.45%
Wireless sensor networks have emerged as a promising technology for a wide range of important applications. A major research challenge in this field is the distributed resource allocation problem, which concerns how the limited resources in a wireless sensor network should be allocated or scheduled to minimize costs and maximize the network capability. In this paper, we propose the Adaptive Distributed Resource Allocation (ADRA) scheme, an adaptive approach for distributed resource allocation in wireless sensor networks. Our scheme specifies relatively simple local actions to be performed by individual sensor nodes in a wireless sensor network for mode management. Each node adapts its operation over time in response to the status and feedback of its neighboring nodes. Desirable global behavior results from the local interactions between nodes. We study the effectiveness of the ADRA scheme for a realistic application scenario; namely, the sensor mode management in an acoustic sensor network to track vehicle movement. We evaluated the scheme via simulations, and also prototyped it using the Crossbow MICA2 motes. Our simulation and hardware implementation results indicate that the ADRA scheme provides a good tradeoff between performance objectives such as coverage area...

Large discreet resource allocation: a hybrid approach based on DEA efficiency measurement.

GOMES, E. G.; MELLO, J. C. C. B. S. de; MEZA, L. A.
Fonte: Pesquisa Operacional, v.28, n.3, p. 597-608, set./dez. 2008. Publicador: Pesquisa Operacional, v.28, n.3, p. 597-608, set./dez. 2008.
Tipo: Artigo em periódico indexado (ALICE)
EN
Relevância na Pesquisa
66.42%
Resource allocation is one of the traditional Operations Research problems. In this paper we propose a hybrid model for resource allocation that uses Data Envelopment Analysis efficiency measures. We use Zero Sum Gains DEA models as the starting point to decrease the computational work for the step-bystep algorithm to allocate integer resources in a DEA context. Our approach is illustrated by a numerical example.; 2008

Do glucocorticoids mediate resource allocation in breeding tree swallows (Tachycineta bicolor)?

Dobson, Emily
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado
EN
Relevância na Pesquisa
66.55%
All individuals allocate limited resources towards self-maintenance (meeting energy requirements for growth and development) and reproduction (producing and rearing offspring). Different physiological systems of the body attempt to balance these processes in order to maximize lifetime reproductive success. The precise mechanisms underlying adaptive allocation towards competing life history traits are unknown. One possible mechanism of mediating resource allocation is through the release of glucocorticoid (GC) hormones. Corticosterone (cort) is the primary GC found in birds, reptiles and amphibians and a good candidate for mediating shifts in resource allocation because (1) challenges that result in reduced energy availability, such as food limitation or disease, induce increased secretion of baseline cort, and (2) cort secretion can result in mobilization of energy stores. To investigate the effects of cort on resource allocation, we conducted two complementary studies in tree swallows (Tachycineta bicolor). First, we compared birds that received cort-implants with birds that received control-implants and un-implanted controls to identify causal effects of increased cort on resource allocation. We found no significant effect of implant type on measures of reproductive effort...

Finance, Comparative Advantage, and Resource Allocation

Jaud, Melise; Kukenova, Madina; Strieborny, Martin
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
EN_US
Relevância na Pesquisa
66.38%
The authors show that exported products exit the US market sooner if they violate the Heckscher-Ohlin notion of comparative advantage. Crucially, this pattern is stronger when exporting country has a well-developed banking system, measured by a high ratio of bank credit over the GDP. Banks thus push firms away from exports that are facing an uphill battle on a competitive foreign market due to a suboptimal use of the domestic factor endowment. The results imply a disciplining role for bank credit in terminating inefficient trade flows. This constitutes a new channel through which finance improves resource allocation in the real economy.

Differential resource allocation strategies for juvenile elephant seals in the highly seasonal Southern Ocean

Field, I.; Bradshaw, C.; Burton, H.; Hindell, M.
Fonte: Inter-research Publicador: Inter-research
Tipo: Artigo de Revista Científica
Publicado em //2007 EN
Relevância na Pesquisa
66.38%
Environmental conditions experienced in early life affect growth and influence life history strategies, especially in seasonal environments. We studied the seasonal and sexual variation in resource allocation in juvenile southern elephant seals to investigate whether they show a seasonal decline in growth. We also examined whether sexual differences in growth may lead to separate growth strategies that suit each sex in maximizing fitness. We examined the variation in length (as a measure of somatic growth), body mass and condition of 470 individual 1- to 4-yr-old elephant seals relative to their different growth strategies. Applying a novel growth function, we observed increased somatic growth in summer compared to winter. Males were larger, had higher proportions of lean tissue and grew faster than females, demonstrating the evolution of a male growth strategy of attaining maximum size quickly, and a female strategy of achieving primiparity at an early age. This evidence supports the idea that seasonal patterns reflect seasonal variation in prey availability and quality, and differential growth strategies promote optimal resource allocation and increase an individual’s probability of survival and future breeding success in the highly dynamic and seasonal Southern Ocean.; Iain C. Field...

Coevolving a computer player for resource allocation games : using the game of Tempo as a test space.

Avery, Phillipa Melanie
Fonte: Universidade de Adelaide Publicador: Universidade de Adelaide
Tipo: Tese de Doutorado
Publicado em //2008
Relevância na Pesquisa
86.65%
Decision-making in resource allocation can be a complex and daunting task. Often there exist circumstances where there is no clear optimal path to choose, and instead the decision maker must predict future need and allocate accordingly. The application of resource allocation can be seen in many organizations, from military, to high end commercial and political, and even individuals living their daily life. We define resource allocation as follows: the allocation of owner’s assets to further the particular cause of the owner. We propose two ways that computers can assist with the task of resource allocation. Firstly they can provide decision support mechanisms, with alternate strategies for the allocations that might not have been previously considered. Secondly, they can provide training mechanisms to challenge human decision makers in learning better resource allocation strategies. In this research we focus on the latter, and provide the following general hypothesis: Coevolutionary algorithms are an effective mechanism for the creation of a computer player for strategic decision-making games. To address this hypothesis, we present a system that uses coevolution to learn new strategies for the resource allocation game of TEMPO. The game of TEMPO provides a perfect test bed for this research...

Case studies that illustrate disinvestment and resource allocation decision-making processes in health care: A systematic review

Polisena, Julie; Clifford, Tammy; Elshaug, Adam Grant; Mitton, Craig; Russell, Erin; Skidmore, Becky
Fonte: Cambridge University Press Publicador: Cambridge University Press
Tipo: Artigo de Revista Científica
Publicado em //2013 EN
Relevância na Pesquisa
66.56%
OBJECTIVE: Technological change accounts for approximately 25 percent of health expenditure growth. To date, limited research has been published on case studies of disinvestment and resource allocation decision making in clinical practice. Our research objective is to systematically review and catalogue the application of frameworks and tools for disinvestment and resource allocation decision making in health care. METHODS: An electronic literature search was executed for studies on disinvestment, obsolete and ineffective technologies, and priority healthcare setting, published from January 1990 until January 2012. Databases searched were MEDLINE, MEDLINE In-Process and Other Non-Indexed Citations, Embase, The Cochrane Library, PubMed, and HEED. RESULTS: Fourteen case studies on the application of frameworks and tools for disinvestment and resource allocation decisions were included. Most studies described the application of program budgeting and marginal analysis (PBMA), and two reports used health technology assessment (HTA) methods for coverage decisions in a national fee-for-service structure. Numerous healthcare technologies and services were covered across the studies. We describe the multiple criteria considered for decision making...

Approximation algorithms for resource allocation optimization.

Liao, Kewen
Fonte: Universidade de Adelaide Publicador: Universidade de Adelaide
Tipo: Tese de Doutorado
Publicado em //2014
Relevância na Pesquisa
66.51%
Nowadays, data storage, server replicas/mirrors, virtual machines, and various kinds of services can all be regarded as different types of resources. These resources play an important role in today’s computer world because of the continuing advances in information technology. It is usual that similar resources are grouped together at the same site, and can then be allocated to geographically distributed clients. This is the resource allocation paradigm considered in this thesis. Optimizing solutions to a variety of problems arising from this paradigm remains a key challenge, since these problems are NP-hard. For all the resource allocation problems studied in this thesis, we are given a set of sites containing facilities as resources, a set of clients to access these facilities, an opening cost for each facility, and a connection cost for each allocation of a facility to a client. The general goal is to decide the number of facilities to open at each site and allocate the open facilities to clients so that the total cost incurred is minimized. This class of the problems extends the classical NP-hard facility location problems with additional abilities to capture various practical resource allocation scenarios. To cope with the NP-hardness of the resource allocation problems...

Efficient Resource Allocation in Multiflow Wireless Networks

Middleton, Gareth B.
Fonte: Universidade Rice Publicador: Universidade Rice
ENG
Relevância na Pesquisa
66.42%
We consider the problem of allocating resources in large wireless net- works in which multiple information flows must be accommodated. In particular, we seek a method for selecting schedules, routes, and power allocations for networks with terminals capable of user-cooperation at the signal level. To that end, we adopt a general information-theoretic communications model, in which the datarate of a wireless link is purely a function of transmission power, pathloss and interference. We begin by studying the case of resource allocation when only point-to-point links are available. The problem is NP-hard in this case, requiring an exponentially-complex exhaustive search to guarantee an optimal solution. This is prohibitively difficult for anything but the smallest of networks, leading us to approximate the problem using a decomposition approach. We construct the solution iteratively, developing polynomial-time algorithms to optimally allocate resources on a per-frame basis. We then update the network graph to reflect the resources consumed by the allocated frame. To manage this decomposition, we present a novel tool, termed the Network-Flow Interaction Chart. By representing the network in both space and time, our techniques trade off interference with throughput for each frame...

Fairness-Adaptive Goodput-Based Resource Allocation in OFDMA Downlink with ARQ

Escudero-Garzás, J. Joaquín; Devillers, Bertrand; García-Armada, Ana
Fonte: IEEE Publicador: IEEE
Tipo: info:eu-repo/semantics/acceptedVersion; info:eu-repo/semantics/article
Publicado em /03/2014 ENG
Relevância na Pesquisa
66.4%
We present a cross-layer resource-allocation (RA) scheme for the downlink in orthogonal frequency-division multiple-access (OFDMA) systems with fairness control among the users, where the resources to be allocated are power, bits per symbol, and subchannels. The use of subchannels, which are defined as group of subcarriers, leads to reducing the complexity of the bandwidth allocation compared with the commonly adopted subcarrier allocation. A goodput-based optimization function, which is derived by combining automatic repeat request (ARQ) and physical (PHY)-layer parameters, is used to perform RA for applications that demand error-free transmissions. Two transmission strategies are considered, with and without concatenation of subchannels, for which two different RA methods are developed, respectively. We also propose an algorithm that improves the complexity associated to both concatenation and nonconcatenation schemes, without appreciable performance loss.; The work was supported by the GRE3N Project under Grant TEC2011-29006-C03-03.

Applicability of computer spreadsheet simulation for solving resource allocation problems

Hicks, Dixon Kendall
Fonte: Monterey, California. Naval Postgraduate School Publicador: Monterey, California. Naval Postgraduate School
Tipo: Tese de Doutorado Formato: 131 p.
EN_US
Relevância na Pesquisa
66.45%
Approved for public release; distribution is unlimited; This thesis investigates the possibility of employing computer spreadsheets as a sophisticated tool to resolve resource allocation dilemmas through simulation techniques. Microsofts Excel 4. 0 is used to analyzed three separate and unique resource allocation problems. First, an inventory distribution system involving different distribution points to illustrate the magnification of uncertainty as the distribution system is lengthened. Second queuing utilization problem faced by an emergency room of a hospital. The third scenario looks at the uncertainty in financial budgeting situation as reflected in the Navy's CHAMPUS budget. A spreadsheet macro using simulation techniques is created for each scenario to illustrate that computer spreadsheets are fully capable of analyzing resource allocation enigmas through simulation methodology; http://archive.org/details/applicabilityofc00hick; Lieutenant, United States Navy

LP-based approximation algorithms for reliable resource allocation

Liao, K.; Shen, H.
Fonte: Oxford University Press (OUP) Publicador: Oxford University Press (OUP)
Tipo: Artigo de Revista Científica
Publicado em //2014 EN
Relevância na Pesquisa
66.51%
We initiate the study of the reliable resource allocation (RRA) problem. In this problem, we are given a set of sites ℱ each with an unconstrained number of facilities as resources. Every facility at site i ∈ ℱ has an opening cost and a service reliability pi. There is also a set of clients to be allocated to facilities. Every client j ∈ accesses a facility at i with a connection cost and reliability lij. In addition, every client j has a minimum reliability requirement (MRR) rj for accessing facilities. The objective of the problem is to decide the number of facilities to open at each site and connect these facilities to clients such that all clients’ MRRs are satisfied at a minimum total cost. The unconstrained fault-tolerant resource allocation problem studied in Liao and Shen [(2011) Unconstrained and Constrained Fault-Tolerant Resource Allocation. Proceedings of the 17th Annual International Conference on Computing and Combinatorics (COCOON), Dallas, Texas, USA, August 14–16, pp. 555–566. Springer, Berlin] is a special case of RRA. Both of these resource allocation problems are derived from the classical facility location theory. In this paper, for solving the general RRA problem, we develop two equivalent primal-dual algorithms where the second one is an acceleration of the first and runs in quasi-quadratic time. In the algorithm's ratio analysis...

O planejamento de alocação de recursos baseado em sistemas multiagentes; Resource allocation planning using multi-agent systems

Bastos, Ricardo Melo
Fonte: Universidade Federal do Rio Grande do Sul Publicador: Universidade Federal do Rio Grande do Sul
Tipo: Tese de Doutorado Formato: application/pdf
POR
Relevância na Pesquisa
66.49%
Este trabalho tem por objetivo propor uma abordagem para o problema de alocação dinâmica de recursos em ambiente de produção baseada no paradigma de multiagentes. Para tanto, é especificada uma arquitetura multiagente genérica chamada M-DRAP - Multi-agent Dynamic Resource Allocation Planning, a partir da qual podem ser derivados modelos particulares. As principais contribuições deste trabalho compreendem: (i) a definição de uma estratégia que permita o planejamento dinâmico de cada recurso no atendimento as demandas das atividades de produção de forma descentralizada e distribuída, através de uma abordagem orientada a projeto; (ii) a proposição de uma organização social baseada em uma abordagem multiagente orientada a mercado, capaz de propiciar relações de negociação entre agentes autônomos no sentido de atenderem aos seus interesses individuais, contribuindo de forma efetiva para a satisfação dos objetivos e restrições temporais e de custos globais ao sistema de produção como um todo; (iii) a especificação de uma arquitetura multiagente derivada do CIMOSA, representando de forma consistente a estrutura funcional e organizacional de um sistema de produção; (iv) a definição de estratégias baseadas em negociação entre os agentes capazes de propiciarem o tratamento das perturbações que afetam o sistema de produção em tempo real. Como contribuindo associada...

Truthful and Fair Resource Allocation

Lai, John Kwang
Fonte: Harvard University Publicador: Harvard University
Tipo: Thesis or Dissertation
EN_US
Relevância na Pesquisa
66.42%
How should we divide a good or set of goods among a set of agents? There are various constraints that we can consider. We consider two particular constraints. The first is fairness - how can we find fair allocations? The second is truthfulness - what if we do not know agents valuations for the goods being allocated? What if these valuations need to be elicited, and agents will misreport their valuations if it is beneficial? Can we design procedures that elicit agents' true valuations while preserving the quality of the allocation? We consider truthful and fair resource allocation procedures through a computational lens. We first study fair division of a heterogeneous, divisible good, colloquially known as the cake cutting problem. We depart from the existing literature and assume that agents have restricted valuations that can be succinctly communicated. We consider the problems of welfare-maximization, expressiveness, and truthfulness in cake cutting under this model. In the second part of this dissertation we consider truthfulness in settings where payments can be used to incentivize agents to truthfully reveal their private information. A mechanism asks agents to report their private preference information and computes an allocation and payments based on these reports. The mechanism design problem is to find incentive compatible mechanisms which incentivize agents to truthfully reveal their private information and simultaneously compute allocations with desirable properties. The traditional approach to mechanism design specifies mechanisms by hand and proves that certain desirable properties are satisfied. This limits the design space to mechanisms that can be written down and analyzed. We take a computational approach...