Service Availability (service + availability)

Distribution by Scientific Domains


Selected Abstracts


Performance analysis and improvement for BitTorrent-like file sharing systems

CONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 13 2007
Ye Tian
Abstract In this paper, we present a simple mathematical model for studying the performance of the BitTorrent (http://www.bittorrent.com) file sharing system. We are especially interested in the distribution of peers in different states of the download job progress. With the model we find that the distribution of the download peers follows an asymmetric U-shaped curve under the stable state, due to BitTorrent's unchoking strategies. In addition, we find that the seeds' departure rate and the download peers' abort rate will influence the peer distribution in different ways notably. We also analyze the content availability under the dying process of the BitTorrent file sharing system. We find that the system's stability deteriorates with decreasing and unevenly distributed online peers, and BitTorrent's built-in ,tit-for-tat' unchoking strategy could not help to preserve the integrity of the file among the download peers. We propose an innovative ,tit-for-tat' unchoking strategy which enables more peers to finish the download job and prolongs the system's lifetime. By playing our innovative strategy, download peers could cooperate to improve the stability of the system by making a trade-off between the current downloading rate and the future service availability. Finally, experimental results are presented to validate our analytical results and support our proposals. Copyright © 2007 John Wiley & Sons, Ltd. [source]


Accounting for Infrastructure Service Delivery by Government: Generational Issues

FINANCIAL ACCOUNTABILITY & MANAGEMENT, Issue 3 2000
Michael McCrae
Infrastructure service provision by government creates huge distributional issues about service availability and performance over time and the relative funding burdens borne by successive generations of consumers across time. But providing financial disclosure on these issues through inter-generational accounting pre-supposes that accounting measurement is both generationally neutral (temporal neutrality) and does not legitimate any particular pattern of distribution. At the very least, accounting measurements of service provision costs should possess the attribute of distributional fairness. They should not bias the inter-generational allocation of cost or funding burdens. We argue that the forced application of inappropriate commercial accounting concepts of asset valuation, depreciation and capital maintenance does produce significant generational bias. More flexibility is required to produce the necessary accounting measurement attributes for financial disclosure on whether government has discharged its continuing accountability for inter-generational equity in burden sharing. We discuss three conceptual issues and illustrate the need for flexibility by proposing an alternative ,flow of obligations' approach which does not require reference to valuations of community service resources or arbitrary cost allocations under depreciation. [source]


Health and social care costs for young adults with epilepsy in the UK

HEALTH & SOCIAL CARE IN THE COMMUNITY, Issue 5 2010
Jennifer Beecham PhD
Abstract Maintaining contact with services will help improve clinical and social outcomes as children with epilepsy move into their adult lives. This study has collated evidence on the extent to which young adults with epilepsy are supported by health and social care services posttransition, and the costs of such support. UK prevalence and service use data were taken from policy and research literature, as well as national data sets and reports. Costs were attached to these data to arrive at agency and overall total costs. There are approximately 42 000 young adults (18,25 years) with epilepsy costing the UK health and social care budgets £715.3 million per annum, on average £17 000 per young adult with epilepsy. A further £61 million falls to the social security budget. Most young adults with epilepsy will rarely use these services, but those with additional health needs have high and often long-term support needs, including supported accommodation and personal care. Current resources used by these young adults are summarised but deficits in service availability can mean long waiting times and sub-optimal treatment. Young adults also want more support to help them take advantage of education and employment opportunities and more information about managing the impacts of epilepsy on their lives. Improving services will cost money, but has the potential to lead to better outcomes for young adults. [source]


Using Telemedicine to Avoid Transfer of Rural Emergency Department Patients

THE JOURNAL OF RURAL HEALTH, Issue 3 2001
Lanis L. Hicks Ph.D
ABSTRACT: Access to emergency treatment in rural areas can often mean the difference between life and death. Telemedicine technologies have the potential of providing earlier diagnosis and intervention, of saving lives and of avoiding unnecessary transfers from rural hospital emergency departments to urban hospitals. This study examined the hypothetical impact of telemedicine services on patients served by the emergency departments of two rural Missouri liospitals and the potential financial impact on the affected hospitals. Of the 246 patients transferred to the hub hospital from the two facilities during 1996, 161 medical records (65.4 percent) were analyzed. Using a conservative approach, only 12 of these cases were identified as potentially avoidable transfers with the use of telemedicine. Of these 12, 5 were admitted to the hub hospital after transfer. In addition to this conservative estimate of avoidable transfers based on current availability of resources in the rural hospitals, two more aggressive scenarios were developed, based on an assumption of increased service availability in the rural hospitals. Economic multipliers were used to estimate the financial impacts on communities in each scenario. This evaluation study demonstrates the potential value of telemedicine use in rural emergency departments to patients, rural hospitals and rural communities. [source]


MIXED OLIGOPOLY, PRODUCT DIFFERENTIATION AND COMPETITION FOR PUBLIC TRANSPORT SERVICES,

THE MANCHESTER SCHOOL, Issue 3 2006
PEDRO CANTOS-SÁNCHEZ
This paper explores frequency and pricing decisions in a horizontally and vertically differentiated duopoly when there is competition between means of transport and where one of the firms need not necessarily maximize profits. The private and the mixed duopoly are compared and distortions from the social optimum are identified, both analytically and numerically. A mixed duopoly does not recover the socially optimal solution. However, the presence of a (public) non-profit maximizing operator is a useful measure to get closer to the social optimum. When both operators are (private) profit maximizers, some control measures such as price caps and minimum service availability would reduce the distortions from the social optimum. [source]