422 research outputs found

    Advances in emergency networking

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    Crisis situations require fast regain of control. Wireless ad-hoc networks will enable emergency services to act upon the actual status of the situation by retrieving and exchanging detailed up-to-date information. Deployment of highbandwidth, robust, self-organising ad-hoc networks will therefore enable quicker response to typical hat/where/when questions, than the more vulnerable low-bandwidth communication networks currently in use. This paper addresses a number of results of the projects AAF (Adaptive Ad-hoc Freeband communications) and Easy Wireless that enable high bandwidth robust ad-hoc networking

    Demystifying Wireless Technologies: Navigating Through The Wireless Technology Maze

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    A significant part of the growth in consumer-to-business electronic commerce is likely to originate from the increasing numbers of mobile computing devices and smart telephone devices. Most of the data from mobile computers will be carried over by emerging wireless networks. Many wireless technologies and standards are now available. As a result, it is becoming increasingly difficult for non-domain experts like managers, to sort through the maze of wireless technologies and standards to make business decisions involving these technologies. This article surveys existing and emerging wireless technologies and uses the Open System Interconnect (OSI) framework to organize the wireless landscape. The survey provides a quick reference to the entire spectrum of wireless technologies in use today

    Distributed multimedia systems

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    A distributed multimedia system (DMS) is an integrated communication, computing, and information system that enables the processing, management, delivery, and presentation of synchronized multimedia information with quality-of-service guarantees. Multimedia information may include discrete media data, such as text, data, and images, and continuous media data, such as video and audio. Such a system enhances human communications by exploiting both visual and aural senses and provides the ultimate flexibility in work and entertainment, allowing one to collaborate with remote participants, view movies on demand, access on-line digital libraries from the desktop, and so forth. In this paper, we present a technical survey of a DMS. We give an overview of distributed multimedia systems, examine the fundamental concept of digital media, identify the applications, and survey the important enabling technologies.published_or_final_versio

    New dynamic bandwidth allocation algorithm analysis: DDSPON for ethernet passive optical networks

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    This project aims to present the state of the art in Dynamic Bandwidth Allocation (DBA) solutions, as well as the study and evaluation of one proposal of DBA algorithm: the Distributed Dynamic Scheduling for EPON (DDSPON), which is the UPC contribution to the research in scheduling algorithms for EPON

    Policy, Federalism, and Regulating Broadband Internet Access

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    Following recent telecommunications mergers, local (mostly municipal and county) governments and the federal government are fighting over who should determine whether cable television systems must make their facilities available to unaffiliated providers of high-speed (“broadband”) Internet service. This intergovernmental dispute is only the latest in a series of such clashes regarding competition and communications policy. A brief review of the policy suggests that substantively, local open-access requirements are not yet warranted. However, the economics of federalism, primarily that the relevant markets are local, indicates that local governments should have the right to choose these policies, perhaps erroneously. Federal preemption could prevent learning from multiple independent local “experiments.” The best case for limiting local authority is if it is only the exploitation of opportunistic ability to extract nationwide rents in exchange for approving transfer of the incumbent’s cable franchise to an acquiring firm. Key Words: Federalism, Internet, regulation, vertical integration JEL Classification Numbers: H1, L5, L1 We find that the welfare change from increasing NHS output could easily be negative, particularly when extra spending is financed by distortionary taxes. In contrast, expanding private health care is always efficiency-improving in our simulations. In our central estimates, increasing private health care by a pound’s worth of output produces an efficiency gain of 55 pence, but increasing national health output produces a net efficiency loss of 32 pence per pound! One reason for these results is that increasing the output of rationed health care has ambiguous effects on the total deadweight losses from waiting costs, but these costs unambiguously fall when the private health sector expands. Financing policies by user fees avoids the efficiency costs of raising distortionary taxes, and it also produces efficiency gains by reducing waiting lists. In fact, increasing national health care output produces an overall efficiency gain in most of our simulations, rather than an efficiency loss, when the policy is financed by higher user fees rather than by distortionary taxes. Still, the policy is generally less efficient than a user fee–financed increase in private health care.

    An Enhanced MPR-Based Solution for Flooding of Broadcast Messages in OLSR Wireless ad hoc Networks

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    A new hybrid model of dengue incidence rate using negative binomial generalised additive model and fuzzy c-means model: a case study in Selangor

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    Dengue is one of the top reason for illness and mortality in the world with beyond one­third of the world's population living in the risk areas of dengue infection. In this study, there are five stages to achieve the research objectives. Firstly, the verification of predetem1ined variables. Secondly, the identification of new datasets after clustered by district and Fuzzy C-Means Model (FCM). Thirdly, the development of models using the existing dataset and the new datasets which clustered by the two different clustering categories. Then, to assess the models developed by using three measurement methods which are deviance (D), Akaike Jnfonnation Criteria (AIC) and Bayesian Infonnation Criteria (BIC} Lastly, the validation of model developed by comparing the value of D, AIC and BIC between the existing model and the new models developed which used the new datasets. There are two different clustering techniques applied which are clustering the data by district and by FCM. This study proposed a new modelling hybrid framework by using two statistical models which are FCM and negative binomial Generalised Additive Model (GAM). This study successfully presents the significant difference in the climatic and non-climatic factors that influenced dengue incidence rate (DIR) in Selangor, Malaysia. Results show that the climatic factors such as rainfall with current month up to 3 months and number of rainy days with current month up to lag 3 months are significant to DIR. Besides, the interaction between rainfall and number of rainy days also shows strong positive relationship to DIR. Meanwhile, non-climatic vaiiables such as population density, number of locality and lag DIR from I month until 3 months also show significant relationship towards DIR For both clustering techniques, there are two clusters fonned and there are four new models developed in this study. After comparing the values of D, AIC ai1d BIC between the existing model and the new models, this study concluded that four new models recorded lower values compared to the existing model. Therefore, the four new models are selected to present the dengue incidence in Selangor

    When Channel Surfers Flip to the Web: Copyright Liability for Internet Broadcasting

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    Digital streaming capabilities have enabled real-time Internet transmission of video signals. The advent of Webcasting will potentially change the way in which programming reaches audiences-increasing diversity in content as well as customer choice. Currently, cable and satellite systems secure retransmission rights to broadcast programming through statutory copyrights, and debate has ensued over whether online retransmitters should benefit from the same. This Article describes the evolution of streaming video over the Internet and examines the economic exploitation of such technology. After offering an overview of the compulsory copyright system, the Article analyzes the applicability of statutory licenses to Internet retransmissions of broadcast video signals. It concludes that compulsory copyrights and attendant regulatory restrictions should extend to real-time secondary transmissions of over-the-air broadcast programming (Internet TV). However, a free market system of negotiation would be more appropriate for Webcasting in a pay-per-view video library model
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