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Coordination in Competitive Environments

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通讯和计算机（中英文版） 2013年第8期10卷 1105-1113页

作者： Salvador Ibarra-Martinez Jose A. Castan-Rocha julio laria-menchaca The Engineering School Autonomous University of Tamaulipas Victoria 87000 Mexico

Navigation Model for a Lego Robot Using a Backpropagation Neural Network

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通讯和计算机（中英文版） 2015年第4期12卷 212-218页

作者： Erick Cervantes Chirinos Jose Antonio Castan Rocha Salvador Ibarra Martinez julio laria menchaca Javier Guzman Obando Mayra Trevino Berrones Emilio Castan Rocha Autonomous University of Tamaulipas Computer Science Tampico Tamaulipas Mexico CP. 89440

An Autonomous Navigation Methodology for a Pioneer 3DX Robot

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Computer Technology and Application 2014年第2期5卷 91-97页

作者： Salvador Ibarra Martinez Jose Antonio Castan Rocha julio laria menchaca Mayra Guadalupe Trevino Berrones Javier Guzman Obando Julissa Perez Cobos Emilio Castan Rocha Computer Science Department Engineering School Autonomous University of Tamaulipas Victoria Tamaulipas 87000 Mexico. Electrical and Electronic Department Technological Institute of Madero City Tampico Tamaulipas 89440 Mexico.

Autonomous navigation is a complex challenge that involves the interpretation and analysis of information about the scenario to facilitate the cognitive processes of a robot to perform free trajectories in dynamic environments. To solve this, the paper introduces a Case-Based Reasoning methodology to endow robots with an efficient decision structure aiming of selecting the best maneuver to avoid collisions. In particular, Manhattan Distance was implemented to perform the retrieval process in CBR method. Four scenarios were depicted to run a set of experiments in order to validate the functionality of the implemented work. Finally, conclusions emphasize the advantages of CBR methodology to perform autonomous navigation in unknown and uncertain environments.

关键词： Autonomous navigation pioneer 3DX robot CBR methodology.

Evaluation of Prediction Algorithms in the Student Dropout Problem

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Journal of Computer and Communications 2020年第3期8卷 20-27页

作者： Luis Earving Lee Salvador Ibarra Martínez José Antonio Castán Rocha Jesús David Terán Villanueva julio laria menchaca Mayra Guadalupe Trevino Berrones Emilio Castán Rocha Faculty of Engineering Autonomous University of TamaulipasTampicoTamaulipasMexico Tec NM/Madero Institute of Technology Madero CityTamaulipasMexico.

University dropout is a growing problem which, in recent years, is using computer techniques to assist in the detection process. The paper presents the evaluation of some prediction algorithms to detect a student with a high possibility of scholar desertion. The approach uses real data from past scholar periods to create a dataset with different information of the students (i.e., personal, economic, and academic records). The algorithms selected in the experimental phase were: J48 decision tree, K-near neighbors, and support vector machine. We use two similarity metrics to split the dataset with cases with at least 80% of similarity to evaluate each case. We use the data from 2010 to 2016 with real students’ information to predict if there exists the possibility of a real academic dropout in one test for a period. The results show that the J48 algorithm reaches a better performance in both experiments. Besides, the tree generated for each student is taken as a path of attention, reaching around 88% of effectiveness. Finally, the conclusions argue the contributions of the paper and propose a future line of research.

关键词： Student Dropout Prediction Algorithms J48 K-Near Neighbors Support Vector Machine

Prefoldins 3 and 5 Play an Essential Role in Arabidopsis Tolerance to Salt Stress

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Molecular Plant 2009年第3期2卷 526-534页

作者： Miguel A. Rodriguez-Milla julio Salinas Departamento de Biologfa de Plantas Centro de Investigaciones Biologicas-CSIC Ramiro de Maeztu 9 28040 Madrid Spain

During the last years, our understanding of the mechanisms that control plant response to salt stress has been steadily progressing. Pharmacological studies have allowed the suggestion that the cytoskeleton may be involved in regulating such a response. Nevertheless, genetic evidence establishing that the cytoskeleton has a role in plant tolerance to salt stress has not been reported yet. Here, we have characterized Arabidopsis T-DNA mutants for genes encoding proteins orthologous to prefoldin （PFD） subunits 3 and 5 from yeast and mammals. In these organisms, PFD subunits, also known as Genes Involved in Microtubule biogenesis （GIM）, form a heterohexameric PFD complex implicated in tubulin and actin folding. We show that, indeed, PFD3 and PFD5 can substitute for the loss of their yeast orthologs, as they are able to complement yeast gim2Δ and gim5Δ mutants, respectively. Our results indicate that pfd3 and pfd5 mutants have reduced levels of α- and β-tubulin compared to the wild-type plants when growing under both control and salt-stress conditions. In addition, pfd3 and pfd5 mutants display alterations in their developmental patterns and microtubule organization, and, more importantly, are hypersensitive to high concentrations of NaCl but not of LiCl or mannitol. These results demonstrate that the cytoskeleton plays an essential role in plant tolerance to salt stress.

关键词： Prefoldins cytoskeleton tubulin actin microtubule salt tolerance Arabidopsis

Linear OPF-based Robust Dynamic Operating Envelopes with Uncertainties in Unbalanced Distribution Networks

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Journal of Modern Power Systems and Clean Energy 2024年第4期12卷 1320-1326页

作者： Bin Liu julio H.Braslavsky Nariman Mahdavi Energy Centre Commonwealth Scientific and Industrial Research Organisation(CSIRO)Newcastle 2300Australia the Network Planning Division TransgridSydney 2000Australia the Energy Systems Program Energy CentreCommonwealth Scientific and Industrial Research Organisation(CSIRO)Newcastle 2300Australia

Dynamic operating envelopes(DOEs),as key enablers to facilitate distributed energy resource(DER)integration,have attracted increasing attention in the past ***,uncertainties,which may come from load forecasting errors or inaccurate network parameters,have been rarely discussed in DOE calculation,leading to compromised quality of the hosting capacity allocation *** letter studies how to calculate DOEs that are immune to such uncertainties based on a linearised unbalanced three-phase optimal power flow(UTOPF)*** uncertain parameters constrained by norm balls,formulations for calculating robust DOEs(RDOEs)are presented along with discussions on their *** cases,including a 2-bus illustrative network and a representative Australian network,are tested to demonstrate the effectiveness and efficiency of the proposed approach.

关键词： Distributed energy resource(DER) dynamic operating envelope(DOE) feasible region robust optimisation uncertainty modelling unbalanced optimal power flow

Inconsistencies in four-dimensional Einstein-Gauss-Bonnet gravity

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Chinese Physics C 2021年第1期45卷 89-96页

作者： julio Arrechea Adria Delhom Alejandro Jimenez-Cano Instituto de Astrofisica de Andalucia(IAA-CSIC) Glorieta de la AstronomiaGranadaSpain Departamento de Fisica Teorica and IFIC Centro Mixto Universidad de Valencia-CSIC.Universidad de ValenciaBuijassot-46100ValenciaSpain Departamento de Fisica Teorica y del Cosmos and CAFPE Universidad de Granada18071 GranadaSpain

We attempt to clarify several aspects concemi ng the recently presented four-dimensional Ein stein-Gauss-Bonnet *** argue that the limiting procedure outlined in[***.124,081301(2020)]generally involves ill-defined terms in the four dimensional field *** ways to circumvent this issue are discussed,alongside remarks regarding specific solutions of the *** prove that,although linear perturbations are well behaved around maximally symmetric backgrounds,the equations for second-order perturbations are illdefined even around a Minkowskia n *** on ally,we perform a detailed analysis of the spherically symmetric solutions and find that the central curvature singularity can be reached within a finite proper time.

关键词： alternative theories of gravity singularities Einstein・Gauss-Bonnet

SIMPLE COMPUTING OF THE CUSTOMER LIFETIME VALUE:A FIXED LOCAL-OPTIMAL POLICY APPROACH

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Journal of Systems Science and Systems Engineering 2014年第4期23卷 439-459页

作者： julio B.Clempner Alexander S.Poznyak Center for Economics Management and Social Research Department of Control Automatics Center for Research and Advanced Studies

In this paper,we present a new method for finding a fixed local-optimal policy for computing the customer lifetime *** method is developed for a class of ergodic controllable finite Markov *** propose an approach based on a non-converging state-value function that fluctuates（increases and decreases） between states of the dynamic *** prove that it is possible to represent that function in a recursive format using a one-step-ahead fixed-optimal ***,we provide an analytical formula for the numerical realization of the fixed local-optimal *** also present a second approach based on linear programming,to solve the same problem,that implement the c-variable method for making the problem computationally *** the end,we show that these two approaches are related：after a finite number of iterations our proposed approach converges to same result as the linear programming *** also present a non-traditional approach for ergodicity *** validity of the proposed methods is successfully demonstrated theoretically and,by simulated credit-card marketing experiments computing the customer lifetime value for both an optimization and a game theory approach.

关键词： Customer lifetime value optimization optimal policy method linear programming ergodic controllable Markov chains asynchronous games

Encroachment drives facilitation at alpine shrublines

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Forest Ecosystems 2024年第1期11卷 62-72页

作者： Yafeng Wang Eryuan Liang J.julio Camarero College of Ecology and Environment Nanjing Forestry UniversityNanjing210037China State Key Laboratory of Tibetan Plateau Earth System Environment and Resources(TPESER)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing100101China Instituto Pirenaico de Ecología(IPE-CSIC) Zaragoza50080Spain

Ongoing encroachment is driving recent alpine shrubline dynamics globally,but the role of shrub-shrub interactions in shaping shrublines and their relationships with stem density changes remain poorly ***,the size and age of shrubs from 26 Salix shrubline populations along a 900-km latitudinal gradient(30°-38°N)were measured and mapped across the eastern Tibetan *** pattern analyses were used to quantify the spatial distribution patterns of juveniles and adults,and to assess spatial associations between *** intensity of univariate and bivariate spatial patterns was related to biotic and abiotic *** mark correlation functions with a quantitative mark(shrub height,basal stem diameter,crown width)were also employed to investigate the spatial relationships between shrub traits of juveniles and *** equation models were used to explore the relationships among conspecific interactions,patterns,shrub traits and recruitment dynamics under climate *** shrublines showed clustered patterns,suggesting the existence of conspecific *** patterns of juveniles and conspecific interactions(potentially facilitation)tended to intensify with increasing soil moisture *** warming before 2010 triggered positive effects on population interactions and spatial patterns via increased shrub ***,summer warming after2010 triggered negative effects on interactions through reduced shrub ***,shrub recruitment shifts under rapid climate change could impact spatial patterns,alter conspecific interactions and modify the direction and degree of shrublines responses to *** changes would have profound implications for the stability of alpine woody ecosystems.

关键词： Alpine shrubline Positive interactions Facilitation Spatial clustering Point pattern analyses