Top PDF Resource allocation for epidemic control in metapopulations.

Resource allocation for epidemic control in metapopulations.

Resource allocation for epidemic control in metapopulations.

The management of diseases involves the expenditure of limited resources, which more often than not are outstripped by the demand for controlling all infected individuals [1–3]. This is often the case when disease occurs simultaneously in different but inter- connected regions [2,4,5]. Treatment of infection in one region such as a state, city, or hospital may affect the potential for spread to another region when there is movement of individuals between the regions. Seeking to control disease outbreaks in more than one region, poses a dilemma for epidemiologists and health adminis- trators of how best to deploy limited resources, such as drugs or trained personnel, amongst the different regions [6–11]. One common objective is to minimise the numbers of infected individuals and hence to minimize the burden of infection during the course of an epidemic [4,12]. For epidemics of the SIS (Susceptible-Infected-Susceptible) form, in which individuals can be re-infected, Rowthorn et al. [10] showed that rather than targeting the region with most infecteds, as might have been intuitively expected, it is instead optimal to give preference to treating the region with the lower levels of infecteds: the remaining regions are treated as residual claimants, receiving treatment only when there is resource left over. The epidemiological intuition underpinning the optimal strategy is understood by noting that since there are only two types of host (susceptible or infected), preferential treatment in a region with low level of infection is equivalent to giving preference to the region with the highest level of susceptibles available for infection. Since, on average an
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Multilayer optimization in radio resource allocation for the packet transmission in wireless networks

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

Wireless networks are characterized by randomness in network topology, and this result in the variation, in time, position and space, of the strength and quality of the signal which propagates along the transmission path between both communication ends. This randomness is normally used in the provision of diversity in all three domains on a point to point link level basis. Diversity mechanisms improve the quality of each individual radio link and enhance the service data rate. At the network or system level this randomness results in multiuser diversity, because the signal impinging on each mobile station antenna array is independent from the others due to the nature of multipath propagation. Examples of opportunistic schedulers, which rely on the multiuser diversity principle to select the user with the best channel quality, at each scheduling instant are: CI and PF. However, provision of diversity mechanisms over the radio link is not enough to satisfy QoS requirements. Actually, CI and PF schedulers normally result in user starvation whenever used in scenarios of mixed real time and non real time application services. As a matter of fact, provision of QoS requirements demands for a cross-layer based design approach, whose principle relies in the combination of the information coming from: the Physical (PHY), Medium Access Control (MAC) and Network layers (including application layer), in order to optimize some cost or revenue function. A packet scheduler whose architecture is implemented according to this cross-layer design paradigm is illustrated in figure 1.
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A Hybrid Reliable Data Transmission based on Ant-agent  Resource Allocation Technique in EEMCC Protocol for  MANETS

A Hybrid Reliable Data Transmission based on Ant-agent Resource Allocation Technique in EEMCC Protocol for MANETS

The ARA technique is developed for reserving the bandwidth for real-time applications in MANETs, which contains two ant agents: FAA and BAA. It probes the bandwidth and reserves the necessary bandwidth needed for the real time applications. When the real-time traffic flow has to be transmitted, the temporary resource which is utilized by other traffic flows gets dropped and the real-time flow starts. The scheme also detects the QoS changes and route breakage and performs congestion control by periodical monitoring of ant agents. To provide lossless real time data to the receiver, a Hybrid Reliable Data Transmission (HRDT) technique is developed with Automatic Retransmission reQuest (ARQ) and Forward Error Correction (FEC) features. The HRDT is used in conjunction with the ARA based EEMCC protocol. Among the two traffic services, the non real time data traffic need to be have a lower loss even if there exist a delay and the real-time traffic need minimum delay irrespective of the losses. Since ARQ involves less delay and overhead, the real-time data is transmitted completely using the ARQ technique. But for the non real-time data, the total data loss occurred at the receivers is estimated for a give time period. If the loss is greater than required threshold value, it transmits data using FEC technique since FEC achieves more reliability than ARQ. Once the loss becomes less than the required threshold, again the data is transmitted using ARQ.Thus the proposed scheme not only controls the reliability in a network but also the overhead and scalability issues of the existing ARQ and FEC techniques. Therefore, the
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Budgeting and resource allocation in universities, a public choice approach

Budgeting and resource allocation in universities, a public choice approach

coming thick and fast in Brazil. Many studies are suggesting evaluation systems and external criteria to control universities production in qualitative terms. Since universities and colleges are not profit-oriented organizations (considering just the fair and serious researching and teaching organizations, of course) the traditional microeconomics and administrative variables used to measure efficiency do not have any direct function. In this sense, It could be created a as if market control system to evaluate universities and colleges production. The budget and the allocation resources mechanism inside it can be used as an incentive instrument to improve quality and productivity. It will be the main issue of this paper.
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Designing equitable antiretroviral allocation strategies in resource-constrained countries.

Designing equitable antiretroviral allocation strategies in resource-constrained countries.

Our model has been applied to the South African province of KwaZulu–Natal, but it can be applied by government health officials in any resource-constrained country. In many of the countries worst affected by the HIV pandemic, scarcity of resources will mean that not everyone that could potentially benefit from ARVs will be able to access them. Many of the decisions that must be made to develop an effective response to the HIV/AIDS epidemic are inevitably underpinned by ethical considerations. Leadership in most resource-constrained regions cannot avoid these decisions. Whilst there has been considerable attention given to South Africa, many other countries worldwide either have plans in place (e.g., Brazil, Thailand, and Botswana) or are in the process of developing national programs for ARV distribu- tion through the public health system (e.g., Mozambique, Malawi, and Kenya) [1]. Legitimate authorities in each nation must come to their own consensus on the priorities and objectives of an ARV rollout, which is not a trivial matter [1,30]. Our objective function and model can be used to calculate allocation strategies that provide equity in access (compensating for geographical isolation), but if authorities in a given nation prioritize a different goal for ARV rollout, then an objective function to optimize can be formulated to reflect the specific national policy goal. Our model can be used by policy makers to determine an optimal scientifically based allocation strategy, based upon the specific objective function. As the ARV rollout commences in KwaZulu–Natal, difficult decisions will have to be made as to how to allocate scarce resources. We have shown that it is possible to obtain a mathematical solution to an equity problem. We suggest that our novel approach could be used to determine optimal equitable allocation strategies for many other resource- constrained countries that are just beginning to receive ARVs [31].
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Strengthening the detection of and early response to public health emergencies: lessons from the West African Ebola epidemic.

Strengthening the detection of and early response to public health emergencies: lessons from the West African Ebola epidemic.

Experts have observed that large-scale threats from EVD are limited primarily to countries with weak public health systems [5]. The current epidemic has supported, if not confirmed, this observation. Previous EVD epidemics, almost all of which occurred in low-and-middle-in- come countries (LMICs) and predominantly in rural areas, have been controlled within 18 weeks, with the largest prior outbreak claiming less than 300 lives. In contrast, the current West African outbreak has now killed more people than all previous EVD outbreaks combined. Whereas WHO generally considers the health infrastructure of involved countries when assess- ing the risk of a potential public health emergency, this outbreak has revealed that a more gran- ular consideration of risk will be of value. Guinea, Sierra Leone, and Liberia are all recovering from prolonged periods of civic unrest and suffering from decimated health systems with limit- ed human resource capacity and thus demonstrate that all LMICs should not be considered the same. For example, Nigeria, another country broadly characterized as a LMIC, provides a clear illustration of how a functional, albeit limited, public health infrastructure can successfully bring an EVD outbreak under control [6]. The country responded rapidly through efforts in public education, isolation, quarantine, contact tracing, and case identification to control an epidemic after only 20 cases and 8 deaths in a little over a month.
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Adaptive Resource Allocation and Internet Traffic Engineering on Data Network

Adaptive Resource Allocation and Internet Traffic Engineering on Data Network

Traffic Engineering (TE) has become the primary method of Internet traffic treatment [3]. Boarder Gateway Protocol (BGP) [4] as the main Internet Exterior Gateway Protocol (EGP) is responsible for transmitting packets across areas and autonomous systems (AS). BGP doesn’t support traffic engineering as it becomes a necessity to optimize the Internet backbone. Traffic engineering can be a manual or automated process through a number of network resource controls [5] such as data resources, control mechanisms, and management tools. Initially, traffic engineering was implemented in IP networks, now it becomes part of the MPLS domain. TE is used to manipulate network traffic to achieve certain requirements. For instance, network utilization of a link is determined by the ratio of used bandwidth in relation to the allocated bandwidth. This can be accomplished by a uniform distribution of network traffic across the network. On the other hand, traffic engineering may be implemented to optimize scarce resources utilization. As one of traffic engineering objectives is to allocate available link bandwidth in relation to the required connection, avoiding congested and oversubscribed links. Load balancing will be handled in both resource allocation and optimal routing choices. [6].
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Access control system for the epidemic marketplace

Access control system for the epidemic marketplace

In a first phase the EM began by having a discretionary GBAC. In its second version / release, the Epidemic Marketplace version 2 (EMv2), it evolved into a decentralized discretionary GBAC. However, while the number of rules and resources increased, the performance decreased. Particularly the access control related web services, which were very slow. This problem had to do with the architecture of the Access Control approach at that time. For each resource shared in the EM, multiple resources had to be created to store access control rules. These rules define the policies of the resource being shared. This lead to a non-scalable Access Control system and motivated an evolution on the EM AC model.
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Joint Dynamic Radio Resource Allocation and Mobility Load Balancing in 3GPP LTE Multi-Cell Network

Joint Dynamic Radio Resource Allocation and Mobility Load Balancing in 3GPP LTE Multi-Cell Network

It is noteworthy that, as far as we know, the influence of resource allocation scheme is seldom considered in the research of load balance. However, load balancing alone, i.e. selecting the appropriate cell-edge user to switch to target neighbor cell, is not enough to improve the user experience in the whole network. This is because improper Radio Resource Mechanism (RRM) may lead to inefficient utilization of system resource, which increases the cell load and unsatisfied user number in hot spots. In fact, load bal- ancing is regarded as a significant RRM which is crucial to guarantee high system performance for OFDMA-based LTE networks. In this paper, resource allocation and load balancing are jointly processed to improve the network performance and user experience. We formulate it as a problem of network resource efficiency maximization, which is subject to inter-cell interference and intra-cell resource constraints. Resource allocation and load balanc- ing are implemented separately in different stages of opti- mization. However, the joint resource allocation consisting of user scheduling and power assignment can be formu- lated as a MIP problem, which has been proven to be NP- hard [17]. We use a heuristic algorithm based on Lagrange Multipliers approach to deal with the sub-optimization case. Another concerned issue of resource allocation is how to balance network throughput and user fairness. To tackle this problem, the presented scheme which is based on modified max carrier to interference ratio (C/I) makes full advantage of multi-user diversity to serve more users while guaranteeing fairness between cell-edge and cell-center users. After a long time collection of measuring results, a practical algorithm which includes handover decision and call admission control is conducted on the load balancing stage, aiming at maximizing the objective function.
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Research on inequality of resource allocation in China since reform and opening up

Research on inequality of resource allocation in China since reform and opening up

time and has obtained a lot of benefits through land expropriation compensation at a low price and auction at a high price, which is actually the monopoly profit of local governments. China's administrative monopoly of resource allocation makes the tentacles of power directly involved in the market, which is very easy to destroy the market order, and not only difficult to break through the market itself, but also further hinder the healthy competition in the market and the improvement of the market economic system. The government, especially the state-owned enterprises under the control of the government, as one of the economic entities in the market economy system, will seek their own private interests just like other economic entities in the market. If the public power in the hands of the government is not effectively restricted, the government will also monopolize the information it has in order to realize its own selfish interests, thus generating various non-public government trust. Therefore, it is particularly important to break the government monopoly and relax market access in order to promote healthy market competition in view of the market factors in China's unbalanced equality allocation of resources.
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Efficient Resource Allocation and Sectorization for Fractional Frequency Reuse (FFR) in LTE Femtocell Systems

Efficient Resource Allocation and Sectorization for Fractional Frequency Reuse (FFR) in LTE Femtocell Systems

The sub-band sizes may vary and we suggest a careful selection of sub-band sizes considering potential data rate requirements. Our proposal limits itself to a fixed resource allocation based on the available radio network planning (RNP) related information. It obviates the need for adaptive control. However, an extension of the proposal can be adaptive allocation considering the channel quality of the users at different frequencies as well as their current data rate demands. In this case, the resource share is adjusted with time among eNodeBs, sectors and layers. The chan- nel-dependent scheduling (CDS) will be more efficient with the adaptive allocation. The eNodeBs may use a dis- tributive control of adaptive resource allocation with an attempt for local optimization. For this purpose, new fields can be added to the Load Information message, which currently exists in the specification for exchange of information between neighboring eNodeBs over the X2 interface. These fields may contain information like the estimated interference at different frequencies, channel quality of the users at different frequencies and current load demand in each layer of each sector of the macrocells. It is possible to support the additional overhead in Load Infor- mation message because X2 can be a high speed link.
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An Approach to the Formal Specification of Holonic Control Systems

An Approach to the Formal Specification of Holonic Control Systems

The flexibility and performance of FMSs depend not only of the individual components, i.e. workstations, storage facilities, etc., but also of the flexibility and performance of the embedded control system [1]. The manufacturing control systems are concerned with coordinating the manufacturing resources to make the desired products. The main functions presented in the manufacturing con- trol system can be split into: process related functions (process planning) and resource allocation related functions. The resource allocation comprises the fol- lowing main functions: resource allocation planning (scheduling), resource alloca- tion plan execution (dispatching, monitoring, diagnosis, reaction to disturbances, etc.) and pathological state handling (deadlock handling, etc.). The scheduling determines an optimal route with respect to some performance criteria, and the plan execution performs the final assignment of resources to the orders, based on the actual state of the manufacturing system and the schedule plans. The pathological state handling intends to keep the system in a safe state and/or recovers it from undesirable states.
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J. Microw. Optoelectron. Electromagn. Appl.  vol.12 número2

J. Microw. Optoelectron. Electromagn. Appl. vol.12 número2

Besides, recent researches have shown the utilization of resource allocation and optimization algorithms such as Local Search (LS), Simulated Annealing (SA), Genetic Algorithm (GA), Particle Swarm optimization (PSO), Ant Colony optimization (ACO) and Game Theory to regulate the transmitted power, bit rate variation and the number of active users in order to maximize the aggregate throughput of the optical networks [7-9]. In the case of the OCP networks optimization, it is necessary to consider the use of distributed iterative algorithms with high performance-complexity tradeoffs and the imperfections of physical layer, which constitute a new research area so far, which was investigated under an analytical perspective in [4-8]. It is worth noting the routed WDM/OCDM networks brings a new combination of challenges with the power control, like amplified spans, multiple links, accumulation, and self-generation of the optical ASE noise, as well as the MAI generated by the OCPs. On the other hand, the dispersive effects, such as chromatic or group velocity dispersion (GVD) and polarization mode dispersion (PMD), are signal degradation mechanisms that significantly affect the overall performance of optical communication systems [10-12].
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A comparative study of resource allocation in Pteridium in different Brazilian ecosystems and its relationship with European studies

A comparative study of resource allocation in Pteridium in different Brazilian ecosystems and its relationship with European studies

through the rhizomes, the rate of frond decomposition is low and the litter layer can be very deep (Marrs and Watt, 2006 ). Whilst litter would normally be considered as part of the necromass, it provides a major ecological function for the species in terms of modification of the microclimate through frost protection (Marrs and Watt, 2006) and in suppressing the ingress of other species (Ghorbani et al., 2006; Marrs and Watt, 2006). We hypothesized that as Pteridium is considered an aggressive and invasive plant, changes in biomass allocation would be expected due to climatic differences representing the adaptation of this genus to occupy different ecosystems. In this case the optimal partitioning hypothesis (Yang et al., 2009) would be accepted. Therefore, we aimed to answer the two following questions: (1) is the biomass allocation similar in two contrasting Brazilian ecosystems? (2) Are the European and South American Pteridium comparable, so that management control strategies derived in one region might be applicable elsewhere?
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Resource allocation model for sensor clouds under the sensing as a service paradigm

Resource allocation model for sensor clouds under the sensing as a service paradigm

The Se-aaS is a cloud-based service model for sensors/data to be shared, allowing for a multi-client access to sensor resources, and multi-supplier deployment of sensors [3]. This way, everyone can benefit from the IoT ecosystem, while benefiting from cloud’s storage and processing capabilities. When incorporating Se-aaS platforms in the application architecture, software components usually have bindings to virtual sensors managed in the cloud. Any workflow, wiring together virtual sensors, actuators and services from various Web sources, is managed on the client side. Managing these mashups at the client side brings, however, significant delays because there will be multiple travelings of data to the client. The proposal in this article is for software components to be able to have bindings to mashups managed in the cloud. The cloud would ensure that events are processed and actuations are triggered, according to the predefined workflow of the mashup, delivering just the final data of interest to the consumer/client application. The whole mashup, or parts of it, may also be consumed by multiple applications. Managing mashups in the cloud brings new challenges when assigning resources (devices and cloud) to consumer needs, as discussed in the following sections. The main contributions of this article are the following:
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Hurdles at work: perceptions of hospital food handlers

Hurdles at work: perceptions of hospital food handlers

The importance of building effective interpersonal com- munication was strongly stressed. According to the state- ments of the participants, there was no space for open and sincere dialogue between the staff members and their superiors, making the workplace atmosphere tense. Ques- tions related to interpersonal interactions were empha- sized, quite often involving conflict between supervisors and subordinates. Complaints were frequent about ill and disrespectful treatment by superiors. According to the par- ticipants, this low standard of employee treatment led to feelings of dissatisfaction and resentment among them. This is more evident in the specific-diets kitchen, where little affinity between employees and supervisors was evi- dent. The milk kitchen employees did not face this prob- lem:
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A generic conceptual and UML model for the multi-echelon distribution supply chain

A generic conceptual and UML model for the multi-echelon distribution supply chain

The simulation approach is used by some authors when the analytical approach became too complicated to describe logistics systems. Brady studied a multi-echelon series network, considering the supply and the demand as stochastic, the simulation model was developed with ARENA and the aim was to assess the impact of the choice of flow management policy of each retailer's service [6]. Beek et al. simulated the dynamics of multi- echelon multi-product, using political control of periodic flows with predetermined lead times [23]. Ng et al. have simulated the running of supply chains composed of N echelons, with stochastic procurement lead times and they have compared the types of flow management policies [18]. Rossetti et al. have analyzed and simulated a system composed of N echelons and N products, and taking into account the fluctuation of demand. The model allows changing the management policy according to the forecasts of anterior demands [20]. Niranjan simulated a multi- echelon system by combining a convergent structure and series structure (three-, four-, five-and m-echelon), the model assumes that is stochastic, the procurement lead time between echelons is constant and the capacity is stochastic [17]. Wan and Zhao presented a simulation model for a multi-echelon made of five actors (manufacturer, distribution center and three retailers), under the assumption that the demand and the procurement lead time are stochastic. The purpose of this model is to analyze the relationship between the fill rate and the average stock of the entire supply chain [24]. Considering the same structure of network adopted by Wan and Zhao, Yu et al. developed a simulation model, with a continuous flow management policy (r, Q), to optimize costs of the inventory with taking into account the target service level [25]. Patil has adopted an integrated approach based on a simulation model, to reduce the cost and to improve sales of a network of two levels (distribution center, three retailers), with the introduction of emergency transshipment between retailers [19]. B. Problem statement and objective
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Analysis of Cloud Network Management Using Resource Allocation and Task Scheduling Services

Analysis of Cloud Network Management Using Resource Allocation and Task Scheduling Services

Abstract—Network failure in cloud datacenter could result from inefficient resource allocation; scheduling and logical segmentation of physical machines (network constraints). This is highly undesirable in Distributed Cloud Computing Networks (DCCNs) running mission critical services. Such failure has been identified in the University of Nigeria datacenter network situated in the south eastern part of Nigeria. In this paper, the architectural decomposition of a proposed DCCN was carried out while exploring its functionalities for grid performance. Virtualization services such as resource allocation and task scheduling were employed in heterogeneous server clusters. The validation of the DCCN performance was carried out using trace files from Riverbed Modeller 17.5 in order to ascertain the influence of virtualization on server resource pool. The QoS metrics considered in the analysis are: the service delay time, resource availability, throughput and utilization. From the validation analysis of the DCCN, the following results were obtained: average throughput (bytes/Sec) for DCCN = 40.00%, DCell = 33.33% and BCube = 26.67%. Average resource availability response for DCCN = 38.46%, DCell = 33.33%, and BCube = 28.21%. DCCN density on resource utilization = 40% (when logically isolated) and 60% (when not logically isolated). From the results, it was concluded that using virtualization in a cloud DataCenter servers will result in enhanced server performance offering lower average wait time even with a higher request rate and longer duration of resource use (service availability). By evaluating these recursive architectural designs for network operations, enterprises ready for Spine and leaf model could further develop their network resource management schemes for optimal performance.
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Men and Money

Men and Money

Furthermore, the present study responds and extends the study of Griskevicius et al. (2012). Griskevicius and colleagues (2012) found that when the sex ratio is male biased, women expect men to pay more for mating-related expenditures (i.e., a Valentine’s Day gift, an entr´ee for a dinner, an engagement ring), they also suggested to explore the precise influence of sex ratio on women’s behavior and to examine the underlying mechanism of the effect of sex ratio on individuals’ economic behavior. The current study responds to this call and comple- ments their findings, by demonstrating that sex ratio also exerts an influence on the intensity of intrasexual competition among women, consequently leads to shifts in women’s preference for relative gain. More importantly, although Griskevicius et al. (2012) found no effect of sex ratio on some aspects of women’s economic behavior, such as saving and borrowing, the present findings suggest that sex ratio can make a difference in women’s economic decision-making behavior. One possible explanation is that sex ratio may only influence women’s beha- viors which are directly related to their reproductive success (e.g., expected spending from men, relative gain over women)
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Book Review – Ivan Tselichtchev, China versus the West: The Global Power Shift of the 21st Century, Singapore: John Wiley & Sons Singapore Pte. Ltd., 2012, 227 pp. + xxviii

Book Review – Ivan Tselichtchev, China versus the West: The Global Power Shift of the 21st Century, Singapore: John Wiley & Sons Singapore Pte. Ltd., 2012, 227 pp. + xxviii

This is a very interesting book regarding the relationship between China and the West focussing on several different aspects: economy, society and politics. This book is made up of 19 chapters and divided into 3 parts. Part 1 covers chapter 1 to chapter 8 which are mainly about the current status and future development of China as the world’s leading producing, exporting and financial power. In Part 2, from Chapter 9 to Chapter 14, Western capitalism and Chinese capitalism are discussed in depth especially during the global downturn and beyond. The author summarizes a very thought-provoking conclusion about who is the winner in the China-West Economic Wars in Part 3, from Chapter 15 and Chapter 19.
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