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Ciudad Obregon, Mexico

The Sonora Institute of Technology is a Mexican public university based in Ciudad Obregón, Sonora, with satellite campuses in Guaymas and Navojoa. Founded in 1955 as a preparatory school called Justo Sierra Institute , it was initially sponsored by Lions International until 1956, when it renamed as Northwestern Institute of Technology . In 1962, Governor Luis Encinas Johnson approved a state law that restructured the institution and gave it its current name. Wikipedia.

Plaut J.A.,University of New Mexico | Wadsworth W.D.,Rice University | Pangle R.,University of New Mexico | Yepez E.A.,Sonora Institute of Technology | And 2 more authors.
New Phytologist | Year: 2013

Summary: Global climate change is predicted to alter the intensity and duration of droughts, but the effects of changing precipitation patterns on vegetation mortality are difficult to predict. Our objective was to determine whether prolonged drought or above-average precipitation altered the capacity to respond to the individual precipitation pulses that drive productivity and survival. We analyzed 5 yr of data from a rainfall manipulation experiment in piñon-juniper (Pinus edulis-Juniperus monosperma) woodland using mixed effects models of transpiration response to event size, antecedent soil moisture, and post-event vapor pressure deficit. Replicated treatments included irrigation, drought, ambient control and infrastructure control. Mortality was highest under drought, and the reduced post-pulse transpiration in the droughted trees that died was attributable to treatment effects beyond drier antecedent conditions and reduced event size. In particular, trees that died were nearly unresponsive to antecedent shallow soil moisture, suggesting reduced shallow absorbing root area. Irrigated trees showed an enhanced response to precipitation pulses. Prolonged drought initiates a downward spiral whereby trees are increasingly unable to utilize pulsed soil moisture. Thus, the additive effects of future, more frequent droughts may increase drought-related mortality. © 2013 New Phytologist Trust.

Martinez C.M.,San Luis Potosi Institute of Scientific Research and Technology | Alvarez L.H.,Sonora Institute of Technology | Celis L.B.,San Luis Potosi Institute of Scientific Research and Technology | Cervantes F.J.,San Luis Potosi Institute of Scientific Research and Technology
Applied Microbiology and Biotechnology | Year: 2013

Humus constitutes a very abundant class of organic compounds that are chemically heterogeneous and widely distributed in terrestrial and aquatic environments. Evidence accumulated during the last decades indicating that humic substances play relevant roles on the transport, fate, and redox conversion of organic and inorganic compounds both in chemically and microbially driven reactions. The present review underlines the contribution of humus-reducing microorganisms in relevant environmental processes such as biodegradation of recalcitrant pollutants and mitigation of greenhouse gases emission in anoxic ecosystems, redox conversion of industrial contaminants in anaerobic wastewater treatment systems, and on the microbial production of nanocatalysts and alternative energy sources. © Springer-Verlag Berlin Heidelberg 2013.

Rodriguez L.-F.,Sonora Institute of Technology | Ramos F.,CINVESTAV
Cognitive Computation | Year: 2014

It has been recognized that human behavior is an observable consequence of the interactions between cognitive and affective functions. This perception has motivated the study of human emotions in disciplines such as psychology and neuroscience and led to the formulation of a number of theories and models that attempt to explain the mechanisms underlying this human process. In the field of artificial intelligence, these theoretical findings have posed a series of challenges in the development of autonomous agents (AAs) capable of exhibiting very believable and human-like behaviors. One of these challenges is the design and implementation of computational models of emotions (CMEs), which are software systems designed to provide AAs with proper mechanisms for the processing of emotional information, elicitation of synthetic emotions, and generation of emotional behaviors. In this paper, we review this type of computational model from the perspective of their development. Particularly, we investigate five design aspects that influence their development process: theoretical foundations, operating cycle, interaction between cognition and emotion, architectural design, and role in cognitive agent architectures. We provide discussions about key issues and challenges in the development of CMEs and suggest research that may lead to more robust and flexible designs for this type of computational model. © 2014 Springer Science+Business Media New York.

Bernal M.,Sonora Institute of Technology | Sala A.,Polytechnic University of Valencia | Jaadari A.,University of Valenciennes and HainautCambresis | Guerra T.-M.,University of Valenciennes and HainautCambresis
Fuzzy Sets and Systems | Year: 2011

In this paper, the stability of continuous-time polynomial fuzzy models by means of a polynomial generalization of fuzzy Lyapunov functions is studied. Fuzzy Lyapunov functions have been fruitfully used in the literature for local analysis of Takagi-Sugeno models, a particular class of the polynomial fuzzy ones. Based on a recent Taylor-series approach which allows a polynomial fuzzy model to exactly represent a nonlinear model in a compact set of the state space, it is shown that a refinement of the polynomial Lyapunov function so as to make it share the fuzzy structure of the model proves advantageous. Conditions thus obtained are tested via available SOS software. © 2011 Elsevier B.V. All rights reserved.

Guerra T.M.,University of Valenciennes and HainautCambresis | Bernal M.,Sonora Institute of Technology
International Journal of Fuzzy Systems | Year: 2012

An original solution to overcome infeasible global quadratic conditions for stability of continuous-time nonlinear models via a Takagi-Sugeno (TS) representation has recently appeared. By changing the paradigm of global stability for something less restrictive a nice solution providing an estimation of the stability domain (local asymptotic conditions) is found, as it is usually the case for nonlinear models for which stability and/or stabilization cannot be reached globally. Strategies to get better estimations with lower computational cost are hereby presented to fully exploit the new approach; some hard nonlinear problems are thus systematically solved. Since the proposed conditions are expressed as linear matrix inequalities (LMIs) they can be efficiently solved by convex optimization techniques. Illustrative examples are provided to show the efficiency of the new technique which outperforms available stability analysis by escaping the quadratic framework. © 2012 TFSA.

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