19 research outputs found

    Fuzzy logic-based approximate event notification in sparse MANETs

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    Mobile Ad-Hoc Networks (MANETs) are an important communication infrastructure to support emergency and rescue operations. To address the frequent disconnections and network partitions that might occur, we have developed a distributed event notification service (DENS) for sparse MANETs. In most event notification solutions, subscriptions are formed with crisp values or crisp value ranges. However, in emergency and rescue operations subscribers may not always have time to give crisp values or crisp value ranges. Moreover, subscriber's interests in queries have gradual nature and subjective measure that calls for computing by words. Therefore, we design and implement a simple fuzzy concept based subscription language allowing more expressive subscriptions and more sophisticated event-filtering. It is built on two new ideas: using features as multi-attribute indexes of the subscription and predicate patterns for processing subscriptions with arbitrary Boolean operators. However, requiring more computational efforts, fuzzy logic introduces performance penalties in the whole network. The proposed services have been evaluated for run-time, space and scalability efficiency. The proposed design framework is extensible to the user- and application-semantics and configurable to the dynamics in data that publish/subscribe paradigm imposes at runtime

    Technology transfer practices and strategies: Issues for Nigerian construction organisations and for research

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    Technology transfer is increasingly being seen as an important issue for economic development and growth. Arguably, this is why developed and especially developing countries are very keen on technology transfer. However, there are those that contend that organisations in the Nigerian construction industry are not as engaged in technology transfer as many would like, and that potential benefits of doing so are not realized. In the same vein, the challenges that confront construction organisations in Nigeria in terms of technology transfer have received very little empirical studies. This paper, therefore, presents a thorough review of literature on strategic issues and choices that Nigerian construction organisations face in grappling with technology transfer, together with associated challenges. Consideration is also given to what technology transfer actually means to such organisations, and how this is viewed in line with other terms such as innovation. The paper argues and concludes that the challenges that confront construction organisations in Nigeria are multifaceted and likely to impact on their strategic choices. In the same vein, it is also argued that these have implications for researchers attempting to investigate technology transfer practices and strategies in construction organisations in Nigeria in terms of their choice of research strategy and design
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