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Jaen, Spain

The University of Jaén is a public university based in Jaén, Andalucía, Spain. It is a young university established by Law 5 / 1993 of the Andalusian Parliament of July 1, 1993. In addition to the principal campus, Campus Lagunillas, located in Jaén, the university has two satellite campuses in Linares and Úbeda. Currently under construction is the Scientific-Technological Campus in Linares. Wikipedia.

Abolafia J.,University of Jaen
Microscopy Research and Technique | Year: 2015

An easy and low-cost method to elaborate a container to dehydrate nematodes and other meiofauna in order to process them for scanning electron microscopy (SEM) is presented. Illustrations of its elaboration, step by step, are included. In addition, a brief methodology to process meiofauna, especially nematodes and kinorhynchs, and illustrations are provided. With this methodology it is possible to easily introduce the specimens, to lock them in a closed chamber allowing the infiltration of fluids and gases (ethanol, acetone, carbon dioxide) but avoiding losing the specimens. After using this meiofauna basket for SEM the results are efficient. Examples of nematode and kinorhynch SEM pictures obtained using this methodology are also included. © 2015 Wiley Periodicals, Inc. Source

Moya A.A.,University of Jaen
Electrochimica Acta | Year: 2013

The harmonic response of ion-exchange membrane systems is studied by using the network simulation method. The ionic transport processes of a binary electrolyte through a system constituted by a cation-exchange membrane and two diffusion boundary layers adjacent to the membrane, are described from the Nernst-Planck flux equations, the electrical neutrality condition in the diffusion boundary layers and the Donnan equilibrium relations at the membrane/solution interfaces. The system is perturbed with a sine current of a single frequency superimposed on a direct current, and the decomposition in a Fourier series of the resulting membrane potential is obtained. The higher-order harmonics, the waveforms and the first harmonic impedance for different values of the dc current, are analyzed and discussed. The non-linearity of the current-voltage relationship of ideal ion-exchange membrane systems in relation with the impedance measurements, is investigated. Special attention is paid to the highest values of the dc current because the diffusion impedance slightly differs from the usual Warburg impedance. The numerical results obtained for the dc resistance of the first harmonic impedance of the system are compared with those obtained from a Taylor series of the well known analytical expression of the steady-state voltage-current characteristic. © 2012 Elsevier Ltd. Source

Martinez L.,University of Jaen | Herrera F.,University of Granada
Information Sciences | Year: 2012

Many real world problems need to deal with uncertainty, therefore the management of such uncertainty is usually a big challenge. Hence, different proposals to tackle and manage the uncertainty have been developed. Probabilistic models are quite common, but when the uncertainty is not probabilistic in nature other models have arisen such as fuzzy logic and the fuzzy linguistic approach. The use of linguistic information to model and manage uncertainty has given good results and implies the accomplishment of processes of computing with words. A bird's eye view in the recent specialized literature about linguistic decision making, computing with words, linguistic computing models and their applications shows that the 2-tuple linguistic representation model [44] has been widely-used in the topic during the last decade. This use is because of reasons such as, its accuracy, its usefulness for improving linguistic solving processes in different applications, its interpretability, its ease managing of complex frameworks in which linguistic information is included and so forth. Therefore, after a decade of extensive and intensive successful use of this model in computing with words for different fields, it is the right moment to overview the model, its extensions, specific methodologies, applications and discuss challenges in the topic. © 2012 Elsevier Inc. All rights reserved. Source

The analysis of δ13C and δ18O from whole rock and the shells of selected foraminifera (Lenticulina and Dentalina) and bairdioid ostracods from Lower Toarcian of the South Iberian Palaeomargin (Western Tethys) is presented with the aim of improving knowledge of the processes and the environmental effects of the Toarcian Oceanic Anoxic Event. In addition, isotopic data are compared with geochemical redox and palaeoproductivity proxies. The microhabitat affected δ13C values, δ13CLenticulina generally being lower than δ13CDentalina due to more depleted 13C values for sediment pore-water in the deep infaunal microhabitat. The lowest values of δ13C (lower part of Serpentinum Zone) happen during suboxic conditions, as indicated by redox proxies, low diversity and abundance of foraminifera and higher TOC values. The fine-grained, organic rich sediments allow for conditions favouring pore-water dissolved inorganic carbon that is depleted in 13C with respect to that of the bottom sea-water, particularly during the suboxic conditions. The δ13C of potential deep infauna (Lenticulina) reflects the oxygen restricted conditions better than shallow infauna (Dentalina) and whole sediment. Regarding δ18O, values from bulk rock present stronger fluctuations and lower values than δ18ODentalina and δ18OLenticulina. The stratigraphic differences between δ18ODentalina and δ18OLenticulina correspond to vital effects, since no important fluctuations in temperature occurred in the bottom sea-water, as deduced from the absence of peaks and stratigraphic trends in the interval studied. The δ18O values do not allow us to infer temperature changes related to the Toarcian Oceanic Anoxic Event in this part of the palaeomargin. © 2013 Elsevier B.V. Source

Liu H.,Northwestern Polytechnical University | Rodriguez R.M.,University of Jaen
Information Sciences | Year: 2014

Decision making is a process common to human beings. The uncertainty and fuzziness of problems demand the use of the fuzzy linguistic approach to model qualitative aspects of problems related to decision. The recent proposal of hesitant fuzzy linguistic term sets supports the elicitation of comparative linguistic expressions in hesitant situations when experts hesitate among different linguistic terms to provide their assessments. The use of linguistic intervals whose results lose their initial fuzzy representation was introduced to facilitate the computing processes in which such expressions are used. The aim of this paper is to present a new representation of the hesitant fuzzy linguistic term sets by means of a fuzzy envelope to carry out the computing with words processes. This new fuzzy envelope can be directly applied to fuzzy multicriteria decision making models. An illustrative example of its application to a supplier selection problem through the use of fuzzy TOPSIS is presented. © 2013 Elsevier Inc. All rights reserved. Source

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