Esteves, Salete; Gokmen, Elçin; Oliveira, José J.
For a family of non-autonomous differential equations with distributed delays, we give sufficient conditions for the global exponential stability of an equilibrium point. This family includes most of the delayed models of neural networks of Hopfield type, with time-varying coefficients and distributed delays. For these models, we establish sufficient conditions for their global exponential stability. The existence and global exponential stability of a periodic solution is also addressed. A comparison of results shows that these results are general, news, and add something new to some earlier publication
Fernandes, Miguel A.; Matos, Samuel G.; Peres, Emanuel; Cunha, Carlos R.; López, Juan A.; Ferreira, P.J.S.G.; Reis, M.J.C.S.; Morais, Raul
Precision viticulture (PV) and precision agriculture (PA) requires the acquisition and proce ssing of a vast collection of data coming typically from large scale and heterogeneous sensor networks. Unfortunately,
sensor integration is far from being simple due to the number of incompatible network specifications and platforms. The adoption of a common, standard communication interfa ce would allow the engineer to abstract the relation between the sensor and the network. This would reduce the development efforts
and emerge as an important step towards the adoption of ‘‘plug-and-play’’ technology in PA/PV sensor networks. This paper explores this need and introduces a framework for smart...
Morais, Elisabete Paulo; Pires, José Adriano; Gonçalves, Ramiro
To compete effectively in the e-business world, an organization must structurally transform its internal foundation. This structural change requires an organization to develop an innovative e-business strategy, focusing on speed to market and breakthrough execution. Despite the recognition and care that in recent years has been dedicated to e-business, there remains a need for continuing research efforts that seek to better understand constraints on the evolution of an organization to a state that can take advantage of e-business possibilities. There
is a special need for this when considering small and medium enterprises, or businesses in developing countries. To minimize risk exposure...
Peres, Emanuel; Fernandes, Miguel A.; Morais, Raul; Cunha, Carlos R.; López, Juan A.; Matos, Samuel R.; Ferreira, P.J.S.G.; Reis, M.J.C.S.
Article in Press
Cunha, Carlos R.; Peres, Emanuel; Morais, Raul; Oliveira, Ana A.; Matos, Samuel G.; Fernandes, Miguel A.; Ferreira, P.J.S.G.; Reis, M.J.C.S.
This paper describes a Viticulture Service-Oriented Framework (VSOF) which turns around context elements or tags that are placed in the field and which can be decoded by mobile devices such as mobile phones or PDAs. The tags are used to automatically associate a field location to the relevant database tables or records and also to access contextual information or services. By pointing a mobile device to a tag, the viticulturalist may download data such as climatic data or upload information such as disease and pest incidence in a simple way, without having to provide coordinates or any other references, and...
Sousa, João Paulo; Carrapatoso, Eurico; Fonseca, Benjamim; Pimentel, Maria da Graça; Bulcão-Neto, Renato
Context-awareness has been regarded as an important feature for mobile services. However, only a few services are sensible to context and the features that are context-aware are still limited. Composition of Web services has received much interest in business-to-business or enterprise application, but not so much interest in business-to- consumer applications. This paper presents iCas, a novel architecture that enables the creation of context-aware services on the fly, and discusses its main components. We compare our approach with similar systems and point out the main differences and advantages. To explore context-awareness to support service composition, iCas uses SeCoM, a semantic...
Cunha, Carlos R.; Peres, Emanuel; Morais, Raul; Reis, Manuel Cabral
This paper describes a business and technological model proposal, known as Inov@Douro, intended to support and to promote competitive and sustained precision agriculture practices in the Portuguese Douro Region. Our approach is based on a distributed cooperative network, tailored to meet the specific needs of viticulture enterprises which also explore tourism as a valuable national and international business source. We present the Inov@Douro model from the knowledge generation point-of-view, intended to support the multidisciplinary concept of a cooperation approach among regional partners. This model aims to represent a new working style for this unique region. As a guideline to attain...