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Germania R.M.,Technical University of Loja | Cueva Carrion S.P.,Technical University of Loja | Tovar Caro E.,Politechnical University of Madrid
2011 IEEE Global Engineering Education Conference, EDUCON 2011 | Year: 2011

The present article shows an investigation made about Standards and Specifications of e-Learning contents, their later selection and analysis of the ones having reusability and interoperability features in Open Educational Resources which are the base of the application purpose in resource development on the instructional design stages and evaluation in already developed resources. © 2011 IEEE. Source


Quispe L.E.,Technical University of Loja | Tandazo R.T.,Technical University of Loja | Galan L.M.,Politechnical University of Madrid
WEBIST 2012 - Proceedings of the 8th International Conference on Web Information Systems and Technologies | Year: 2012

A mobile ad hoc network MANET is a collection of wireless mobile nodes that can dynamically configure a network without a fixed infrastructure or centralized administration. This makes it ideal for emergency and rescue scenarios where information sharing is essential and should occur as soon as possible. This article discusses which of the routing strategies for mobile ad hoc networks: proactive, reactive and hierarchical, have a better performance in such scenarios. Using a real urban area being set for the emergency and rescue scenario, we calculate the density of nodes and the mobility model needed for validation. The NS2 simulator has been used in our study. We also show that the hierarchical routing strategies are beffer suited for this type of scenarios. Source


Quispe L.E.,Technical University of Loja | Galan L.M.,Politechnical University of Madrid
WEBIST 2012 - Proceedings of the 8th International Conference on Web Information Systems and Technologies | Year: 2012

Providing QoS in the context of Ad Hoc networks includes a very wide field of application from the perspective of every level of the architecture in the network. Saying It in another way, It is possible to speak about QoS when a network is capable of guaranteeing a trustworthy communication in both extremes, between any couple of the network nodes by means of an efficient Management and administration of the resources that allows a suitable differentiation of services in agreement with the characteristics and demands of every single application. The principal objective of this article is the analysis of the quality parameters of service that protocols of routering reagents such as AODV and DSR give in the Ad Hoc mobile Networks; all of this is supported by the simulator ns-2. Here were going to analyze the behavior of some other parameters like effective channel, loss of packages and latency in the protocols of routering. Were going to show you which protocol presents better characteristics of Quality of Service (QoS) in the MANET networks. Source


Martin F.,Charles III University of Madrid | Moreno L.,Charles III University of Madrid | Blanco D.,Charles III University of Madrid | Munoz M.L.,Politechnical University of Madrid
Robotics and Autonomous Systems | Year: 2014

The global localization problem for mobile robots is addressed in this paper. In this field, the most common approaches solve this problem based on the minimization of a quadratic loss function or the maximization of a probability distribution. The distances obtained from the perceptive sensors are used together with the predicted ones (from the estimates in the known map) to define a cost function or a probability to optimize. In our previous work, we developed an optimization-based global localization module that used evolutionary computation concepts. In particular, the algorithm engine was the Differential Evolution method. In this work, this algorithm has been modified including the minimization of the Kullback-Leibler divergence between true observations and estimates. This divergence is used to calculate the cost function of the localization module. The algorithm has been tested in different situations and the most important improvement is the ability to cope with different types of occlusions. © 2013 Elsevier B.V. All rights reserved. Source


Melida H.,University of Leon | Melida H.,Politechnical University of Madrid | Largo-Gosens A.,University of Leon | Novo-Uzal E.,University of Murcia | And 7 more authors.
Journal of Integrative Plant Biology | Year: 2015

Maize (Zea mays L.) suspension-cultured cells with up to 70% less cellulose were obtained by stepwise habituation to dichlobenil (DCB), a cellulose biosynthesis inhibitor. Cellulose deficiency was accompanied by marked changes in cell wall matrix polysaccharides and phenolics as revealed by Fourier transform infrared (FTIR) spectroscopy. Cell wall compositional analysis indicated that the cellulose-deficient cell walls showed an enhancement of highly branched and cross-linked arabinoxylans, as well as an increased content in ferulic acid, diferulates and p-coumaric acid, and the presence of a polymer that stained positive for phloroglucinol. In accordance with this, cellulose-deficient cell walls showed a fivefold increase in Klason-type lignin. Thioacidolysis/GC-MS analysis of cellulose-deficient cell walls indicated the presence of a lignin-like polymer with a Syringyl/Guaiacyl ratio of 1.45, which differed from the sensu stricto stress-related lignin that arose in response to short-term DCB-treatments. Gene expression analysis of these cells indicated an overexpression of genes specific for the biosynthesis of monolignol units of lignin. A study of stress signaling pathways revealed an overexpression of some of the jasmonate signaling pathway genes, which might trigger ectopic lignification in response to cell wall integrity disruptions. In summary, the structural plasticity of primary cell walls is proven, since a lignification process is possible in response to cellulose impoverishment. © 2015 Institute of Botany, Chinese Academy of Sciences. Source

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