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Service Capacity (service + capacity)

Distribution by Scientific Domains

Business, Economics, Finance and Accounting	50%

Selected Abstracts

Prioritized e-mail servicing to reduce non-spam delay and loss: A performance analysis

INTERNATIONAL JOURNAL OF NETWORK MANAGEMENT, Issue 4 2008
Muhammad N. Marsono
This paper proposes a prioritized e-mail servicing on e-mail servers to reduce the delay and loss of non-spam e-mails due to queuing. Using a prioritized two-queue scheme, non-spam e-mails are queued in a fast queue and given higher service priority than spam e-mails that are queued in a slow queue. Four prioritized e-mail service strategies for the two-queue scheme are proposed and analyzed. We modeled these four strategies using discrete-time Markov chain analysis under different e-mail traffic loads and service capacities. Non-spam e-mails can be delivered within a small delay, even under heavy e-mail loadings and high spam-to-non-spam a priori. Results from our analysis of the two-queue scheme show that it gives non-spam delay and loss probability two orders of magnitude smaller than the typical single-queue approach during heavy spam traffic. Moreover, prioritized e-mail servicing protects e-mail servers from spam attacks. Copyright © 2007 John Wiley & Sons, Ltd. [source]

Resource allocation for statistical quality of service provision in buffered crossbar switches,

INTERNATIONAL JOURNAL OF COMMUNICATION SYSTEMS, Issue 6 2008
Qiang Duan
Abstract The buffered crossbar switch is a promising switching architecture that plays a crucial role for providing quality of service (QoS) in computer networks. Sufficient amount of resources,bandwidth and buffer space,must be allocated in buffered crossbar switches for QoS provision. Resource allocation based on deterministic QoS objectives might be too conservative in practical network operations. To improve resource utilization in buffered crossbar switches, we study the problem of resource allocation for statistical QoS provision in this paper. First, we develop a model and techniques for analyzing the probabilistic delay performance of buffered crossbar switches, which is described by the delay upper bound with a prescribed violation probability. Then, we determine the required amounts of bandwidth and buffer space to achieve the probabilistic delay objectives for different traffic classes in buffered crossbar switches. In our analysis, we apply the effective arrival envelope to specify traffic load in a statistical manner and characterize switch service capacity by using the service curve technique. Instead of just focusing on one specific type of scheduler, the model and techniques developed in this paper are very flexible and can be used for analyzing buffered crossbar switches with a wide variety of scheduling algorithms. Copyright © 2007 John Wiley & Sons, Ltd. [source]

District health systems in a neoliberal world: a review of five key policy areas,

INTERNATIONAL JOURNAL OF HEALTH PLANNING AND MANAGEMENT, Issue S1 2003
Malcolm Segall
Abstract District health systems, comprising primary health care and first referral hospitals, are key to the delivery of basic health services in developing countries. They should be prioritized in resource allocation and in the building of management and service capacity. The relegation in the World Health Report 2000 of primary health care to a ,second generation' reform,to be superseded by third generation reforms with a market orientation,flows from an analysis that is historically flawed and ideologically biased. Primary health care has struggled against economic crisis and adjustment and a neoliberal ideology often averse to its principles. To ascribe failures of primary health care to a weakness in policy design, when the political economy has starved it of resources, is to blame the victim. Improvement in the working and living conditions of health workers is a precondition for the effective delivery of public health services. A multidimensional programme of health worker rehabilitation should be developed as the foundation for health service recovery. District health systems can and should be financed (at least mainly) from public funds. Although in certain situations user fees have improved the quality and increased the utilization of primary care services, direct charges deter health care use by the poor and can result in further impoverishment. Direct user fees should be replaced progressively by increased public finance and, where possible, by prepayment schemes based on principles of social health insurance with public subsidization. Priority setting should be driven mainly by the objective to achieve equity in health and wellbeing outcomes. Cost effectiveness should enter into the selection of treatments for people (productive efficiency), but not into the selection of people for treatment (allocative efficiency). Decentralization is likely to be advantageous in most health systems, although the exact form(s) should be selected with care and implementation should be phased in after adequate preparation. The public health service should usually play the lead provider role in district health systems, but non-government providers can be contracted if needed. There is little or no evidence to support proactive privatization, marketization or provider competition. Democratization of political and popular involvement in health enhances the benefits of decentralization and community participation. Integrated district health systems are the means by which specific health programmes can best be delivered in the context of overall health care needs. International assistance should address communicable disease control priorities in ways that strengthen local health systems and do not undermine them. The Global Fund to Fight AIDS, Tuberculosis and Malaria should not repeat the mistakes of the mass compaigns of past decades. In particular, it should not set programme targets that are driven by an international agenda and which are achievable only at the cost of an adverse impact on sustainable health systems. Above all the targets must not retard the development of the district health systems so badly needed by the rural poor. Copyright © 2003 John Wiley & Sons, Ltd. [source]

Strategic behavior in a service industry

MANAGERIAL AND DECISION ECONOMICS, Issue 2 2002
Pekka Ilmakunnas
A model of service duopoly is formulated, where the arrival of customers and their service time in the firm are stochastic. The firms first choose the service capacity, and given the capacity they then choose the price in a Bertrand competition. Capacity choices have a negative externality on the competitor, since increased capacity in one firm decreases its expected full price (price plus cost of waiting) and leads to a flow of customers from the other firm. If the firms choose capacities strategically, it is optimal to underinvest compared to the non-strategic case, but this result may arise in different ways. By underinvesting the firms commit themselves to longer queues (lower quality) to relax price competition. Copyright © 2002 John Wiley & Sons, Ltd. [source]

Price dispersion in a model of identical agents with perfect information

PACIFIC ECONOMIC REVIEW, Issue 1 2004
Zhiqi Chen
The driving force in the model is service capacity and congestion cost. Each firm chooses a service capacity. Customers of a firm bear a congestion cost which, for a fixed service capacity, is an increasing function of the number of customers served by this firm. We demonstrate that under certain conditions the combined profit of two firms and the total surplus are higher in a price-dispersion equilibrium than in a single-price equilibrium. [source]