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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

Improving Vehicular Mobility in Urban Traffic Using Ubiquitous Computing

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journal of Computer and Communications 2016年第10期4卷 57-62页

作者： j. A. castán S. Ibarra Martínez j. Laria Menchaca M. G. Treviño Berrones j. Pérez Cobos E. castán rocha Faculty of Engineering Autonomous University of Tamaulipas Victoria City Mexico Madero Institute of Technology Tamaulipas Mexico

The paper introduces a novel paradigm to use ubiquitous computing in urban traffic control as a methodology to include the benefits of considering physical elements implicated in the environment. This promising idea arises from previous results in the literature, where ubiquitous computing achieves significant and promising results in diverse scenarios. Some works in the state-of- the-art clearly state that traditional traffic light signals are not capable of offering higher service levels when they should control the vehicular mobility because of different constraints. In this sense, the paper proposes an adaptation of the main ideas of ubiquitous computing as a metaphor to facilitate the interaction between users and traffic infrastructures in order to improve the users’ experience on the road.

关键词： Ubiquitous Computing Urban Traffic Control Intelligent Transport System

A Comparison of Machine Learning Techniques in the Carpooling Problem

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journal of Computer and Communications 2020年第12期8卷 159-169页

作者： M. A. Arteaga Santos C. Méndez Santos S. Ibarra Martínez j. A. castán rocha j. Laria Menchaca j. D. Terán Villanueva M. G. Treviño Berrones j. Pérez Cobos E. castán rocha Faculty of Engineering Autonomous University of Tamaulipas Tamaulipas Mexico Tecnológico nacional de México/Instituto Tecnológico de Ciudad Madero Tamaulipas Mexico

Urban traffic congestion is a severe and widely studied problem over the decade because of the negative impacts. However, in recent years some approaches emerge as proper and suitable solutions. The Carpooling initiative is one of the most representative efforts to propitiate a responsible use of particular vehicles. Thus, the paper introduces a carpooling model considering the users’ preference to reach an appropriate match among drivers and passengers. In particular, the paper conducts a study of 6 of the most avid classified techniques in machine learning to create a model for the selection of travel companions. The experimental results show the models’ precision and assess the best cases using Friedman’s test. Finally, the conclusions emphasize the relevance of the proposed study and suggest that it is necessary to extend the proposal with more drives and passengers’ data.

关键词： Carpooling Machine Learning Techniques Vehicle Traffic Congestion

Dynamics of air transport networks：A review from a complex systems perspective

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Chinese journal of Aeronautics 2017年第2期30卷 469-478页

作者： Luis E.C.rocha Department of Public Health Sciences Karolinska Institutet Stockholm 17177 Sweden Department of Mathematics University of Namur 5000 Belgium

Air transport systems are highly dynamic at temporal scales from minutes to *** dynamic behavior not only characterizes the evolution of the system but also affect the system＇s *** the evolutionary mechanisms is thus fundamental in order to better design optimal air transport networks that benefits companies,passengers and the *** this review,we briefly present and discuss the state-of-the-art on time-evolving air transport *** distinguish the structural analysis of sequences of network snapshots,ideal for long-term network evolution（*** evolution）,and temporal paths,preferred for short-term dynamics（*** evolution）.We emphasize that most previous research focused on the first modeling approach（***-term） whereas only a few studies look at high-resolution temporal *** conclude the review highlighting that much research remains to be done,both to apply already available methods and to develop new measures for temporal paths on air transport *** particular,we identify that the study of delays,network resilience and optimization of resources（aircraft and crew） are critical topics.

关键词： Air transport Airport network Complex network Dynamic network Temporal network

Colloidal(Gd0.98nd0.02)2O3 nanothermometers operating in a cell culture medium within the first and second biological windows

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journal of Rare Earths 2020年第5期38卷 483-491页

作者： M.L.Debasu H.Oliveira j.rocha L.D.Carlos Department of Physics CICECO-Aveiro Institute of MaterilsUniversidade de Aveiro3810-193AveiroPortugal Department of Chemistry CICECO-Aveiro Institute of MaterialsUniversidade de Aveiro3810-193AveiroPortugal Department of Biology CESAMLaboratory of Biotechnology and CytomicsUniversidade de Aveiro3810-193AveiroPortugal

non-contact,self-referenced and near-infrared luminescent nanothermometers have been recognized as emerging tools in the fields of nanomedicine and nanotechnology due to their great capability of precise temperature readout at the nanoscale and real-time deep-tissue ***,the development of multifunctional and biocompatible luminescent nanothermometers operating within the optically transparent biological windows with high thermal sensitivity(>2.0%/K)remains ***,we present(Gd0.98nd0.02)2O3 nanothermometers operated effectively within the first and second biological windows upon continuous-wave laser diode excitation at 808 *** thermometric parameters are defined by the relative changes in the emission intensities originating from the two Stark components of the 4 F3/2 level(R2 and R1)to the 4 I9/2(900-1000 nm),4 I11/2(1035-1155 nm)and 4 I13/2(1300-1450 nm)*** thermo metric parameters are evaluated for colloidal samples in a cell culture medium and powder samples,and the highest thermal sensitivity(2.18%/K at 298 K)is attained for the former in the first biological window(both the excitation and emission in the 800-965 nm range).The repeatability and temperature uncertainty are 99%and 1.2 K,*** nanothermometers are biocompatible with human MnT-1 melanoma and HaCaT cells for 24 h of exposure and nanoparticle concentration up to 0.400 mg/mL,showing their potential for applications in nanomedicine,e.g.,intracellular imaging and temperature mapping.

关键词： Gd2O3 nd3^+-doped nanoparticles Luminescent nanothermometry Thermal sensitivity Cytotoxicity of nanoparticles Rare earths

Historical relationships of areas of endemism of the Brazilian Atlantic rain forest： a cladistic biogeographic analysis of harvestman taxa （Arachnida： Opiliones）

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Current Zoology 2017年第5期63卷 525-535页

作者： Marcio B. DASILVA Ricardo PInTO-DA-rocha juan j. MORROnE Departamento de Sistematica e Ecologia CCEN Universidade Federal da Paraiba Cidade Universitaria Joao Pessoa PB Brazil Departamento de Zoologia Instituto de Biociencias Universidade de Sao Paulo Sao Paulo SP Brazil Museo de Zoologia "Alfonso L. Herrera" Departamento de Biologia Evolutiva Facultad de Ciencias Universidad Nacional Autdnoma de Mexice (UNAM) 04510 Mexico City Mexico

Based on a cladistic biogeographic analysis of 6 species-level phylogenies of harvestman taxa, wesearched for congruence in the historical relationships of 12 areas of endemism of the BrazilianAtlantic Rain Forest. We constructed general area cladograms using Primary Brooks ParsimonyAnajysis （BPA）, BPA of nodes, and paralogy-free subtree analysis. These analyses resulted in 6general area cladograms, that allow to infer a general pattern of the relationships among areas ofendemism from the Brazilian Atlantic Rain Forest. northern areas resulted related basally showingmain disjunctions at the Doce River Valley and Todos os Santos Bay/S^o Francisco River *** remaining areas of endemism were included in a southern and a southeastern block, sepa-rated by the Ribeira do Iguape Valley. Incongruence Length Differences tests showed no significantincongruence among the resulting cladograms and other matrix partitions. We concluded that tec-tonism and ancient marine transgressions were the probable processes responsible for the maindisjunctions, whereas neogene refugia seem to have caused the more recent disjunctions. Thegeneral pattern and redundancy in area relationships suggest a model of main reiterative barriersin diversification at multiple times for the evolution of the Atlantic Rain Forest. The renewal of cla-distic biogeography and the search for common biogeographic patterns are discussed.

关键词： dispersal, historical biogeography, Mata Atlantica, speciation, vicariance.

Pesticides in a temperate coastal lagoon in southwest Europe (Ria de Aveiro, Portugal) – Risk assessment and acute assays with Artemia and Daphnia

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Emerging Contaminants 2024年第2期10卷 40-56页

作者： Maria joão rocha Eduardo rocha Laboratory of Histology and Embryology Department of MicroscopyICBAS-School of Medicine and Biomedical SciencesUniversity of Porto(U.Porto)Portugal Team of Animal Morphology and Toxicology Interdisciplinary Centre of Marine and Environmental Research(CIIMAR/CIMAR)U.PortoPortugal

The Ria de Aveiro lagoon has been considered one of the most important Southern European long-term monitoring sites(LTER-site)concerning climate change and anthropogenic ***,studies concerning pesticide contamination herein are few and mostly ***,56 pesticides dissolved in the aqueous phase(DAP)and suspended particulate matter(SPM)were examined to fill the knowledge gap,considering the hydrophobic nature of most evaluated *** samples were taken seasonally from eight sites,and both DAP and SPM fractions were analysed by gas-chromatography-mass *** annual average concentrations of fungicides,herbicides and insecticides were≈57 ng/L,≈409 ng/L and≈1058 ng/L in DAP and≈7μg/g,≈28μg/g and≈67μg/g in *** pesticides and the excessive phosphate concentrations suggest that the lagoon's water quality may be hazardous to biota and *** were identified as the most threatened trophic level using deterministic risk assessment,with chlorpyriphos and chlorfenvinphos being the primary *** experiments with Artemia and Daphnia supported the suppositions.

关键词： Coastal lagoon Invertebrate bioassays Risk evaluation Waterborne pesticides

Elevated nitric oxide and 3',5' cyclic guanosine monophosphate levels in patients with alcoholic cirrhosis

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World journal of Gastroenterology 2008年第2期14卷 236-242页

作者： Cíntia Siqueira Miguel Carneiro de Moura Ana júlia Pedro Paula rocha Center of Gastroenterology Institute of Molecular Medicine School of Medicine University of Lisbon Portugal Department of Medicine Ⅱ University Hospital of Santa MariaLisbonPortugal

AIM: To evaluate whether serum levels of nitric oxide (nO ·) and plasma levels of cyclic guanosine monophosphate (cGMP) and total glutathione (GSH) are altered in patients with alcoholic cirrhosis and to examine their correlation with the severity of liver ***: Twenty-six patients with alcoholic liver cirrhosis were studied. Serum levels of nO · and plasma levels of cGMP and GSH were measured in 7 patients with compensated alcoholic cirrhosis (Child-Pugh A) and 19 patients with advanced cirrhosis (Child-Pugh B and C). The model for end-stage liver disease (MELD) score was evaluated. Sixteen healthy volunteers served as controls. Liver enzymes and creatinine levels were also ***: nO · and cGMP levels were higher in patients with Child-Pugh B and C cirrhosis than in Child-Pugh A cirrhosis or controls (nO ·: 21.70 ± 8.07 vs 11.70 ± 2.74; 21.70 ± 8.07 vs 7.26 ± 2.47 μmol/L, respectively; P nd (cGMP: 20.12 ± 6.62 vs 10.14 ± 2.78; 20.12 ± 6.62 vs 4.95 ± 1.21 pmol/L, respectively; P ne levels were lower in patients with Child-Pugh B and C cirrhosis than in patients with Child-Pugh A cirrhosis or controls (16.04 ± 6.06 vs 23.01 ± 4.38 or 16.04 ± 6.06 vs 66.57 ± 26.23 μmol/L, respectively; P nificant correlation between nO · and cGMP levels in all patients with alcoholic cirrhosis. A significant negative correlation between reduced glutathione/glutathione disulfide and the MELD score was found in all cirrhotic ***: Our results suggest a role for oxidative stress in alcoholic liver cirrhosis, which is more significant in decompensated patients with higher levels of nO ·and cGMP and lower GSH levels than in compensated and control patients. Altered mediator levels in decompensated patients may influence the hemodynamic changes in and progression of liver disease.

关键词： Oxidative stress nitric oxide Alcoholic cirrhosis Fibrosis Model for end-stage liver disease

A Long-Range Generalized Predictive Control Algorithm for a DFIG Based Wind Energy System

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IEEE/CAA journal of Automatica Sinica 2019年第5期6卷 1209-1219页

作者： j.S.Solis-Chaves Lucas L.Rodrigues C.M.rocha-Osorio Alfeu j.Sguarezi Filho the Department of Energy Engineering at the Federal University of ABC-UFABC Santo AndreSPBrazil

This paper presents a new Long-range generalized predictive controller in the synchronous reference frame for a wind energy system doubly-fed induction generator based. This controller uses the state space equations that consider the rotor current and voltage as state and control variables, to execute the predictive control action. Therefore, the model of the plant must be transformed into two discrete transference functions, by means of an auto-regressive moving average model, in order to attain a discrete and decoupled controller, which makes it possible to treat it as two independent single-input single-output systems instead of a magnetic coupled multiple-input multiple-output system. For achieving that, a direct power control strategy is used, based on the past and future rotor currents and voltages estimation. The algorithm evaluates the rotor current predictors for a defined prediction horizon and computes the new rotor voltages that must be injected to controlling the stator active and reactive powers. To evaluate the controller performance, some simulations were made using Matlab/Simulink. Experimental tests were carried out with a small-scale prototype assuming normal operating conditions with constant and variable wind speed profiles. Finally, some conclusions respect to the dynamic performance of this new controller are summarized.

关键词： Direct power control doubly-fed induction generator flux oriented control generalized predictive control long-range predictive control wind energy systems