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The improvement of an object-oriented classification using multi-temporal MODIS EVI satellite data

International Journal of Digital Earth 2009年第3期2卷 219-236页

作者： Y.Gao J.-F.Mas a.navarrete Centro de Investigaciones en Ecosistemas-Universidad Nacional Autonoma de Mexico(UNAM) Antigua Carretera a Pa tzcuaro No.8701Col.Ex Hacienda de San Jose de la Huerta C.P.58190 MoreliaMichoacanMexico Centro de Investigaciones en Geografıa Ambiental-Universidad Nacional Autonoma de Mexico(UNAM) Antigua Carretera a Pa tzcuaro No.8701Col.Ex Hacienda de San Jose de la Huerta C.P.58190 MoreliaMichoacanMexico

This paper investigates the contribution of multi-temporal enhanced vegetation index(EVI)data to the improvement of object-based classification accuracy using multi-spectral moderate resolution imaging spectral-radiometer(MODIS)*** object-oriented classification,similar pixels are firstly grouped together and then classified;the produced result does not suffer the speckled appearance and closer to human *** data are from the MODIS sensor aboard Terra spacecraft.69 EVI data(scenes)were collected during the period of three years(20012003)in a mountainous vegetated *** data sets were used to study the phenology of the land cover *** land cover types show distinct fluctuations over time in EVI values and this information might be used to improve object-oriented land cover *** experiments were carried out:one was only with single date MODIS multispectral data,and the other one including also the 69 EVI *** classes were distinguished:temperate forest,tropical dry forest,grassland,irrigated agriculture,rain-fed agriculture,orchards,lava flows and human *** two classifications were evaluated with independent verification data,and the results showed that with multitemporal EVI data,the classification accuracy was improved 5.2%.Evaluated by McNemar’s test,this improved was significant,with significance level p=0.01.

关键词： enhanced vegetation index(EVI) moderate resolution imaging spectral-radiometer(MODIS) phenology object-based image classification

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Epidemiologic characteristics of death by burn injury from 2000 to 2009 in Colombia, South America:a population-based study

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Burns & Trauma 2016年第1期4卷 60-67页

作者： Norberto navarrete Nelcy Rodriguez Burn Intensive Care Unit Simón Bolívar HospitalBogotáColombia. ClinicalEpidemiology and Biostatistics Department Javeriana UniversityBogotáColombia. Department of Statistics National University of ColombiaBogotáColombia.

Background:Burns are one of the most severe traumas that an individual can *** World Health Organization(WHO)affirms that injuries related to burns are a global public health problem mainly in low-and middle-income *** first step towards reducing any preventable injury is based on accurate *** Colombia,the basic epidemiological characteristics of burn injuries are *** objectives were establishing the causes,high-risk populations,mortality rate,and tendencies of burn ***:Observational,analytical,population-based study based on official death certificate occurred between 2000 and *** codes of the International Classification of Diseases-10th Revision(ICD-10)related to burns were *** mortality rates were standardized using the WHO world average age weights 2000–*** determine the tendency,an average annual percent change(AACP)was ***:A total of 5448 deaths due to burns were identified;78.4%were *** crude and adjusted burn mortality rate was 1.270 and 1.302 per 100,000,*** AACP was?5.25%.Electrical injury caused the greatest number of deaths(49.5%),followed by fire and lightning injuries.A total of 1197(22.1%)children were under 15 years *** causes of deaths were different among age groups.59.4%deaths occurred outside health ***:This study is a first step in identifying the main causes of death and groups with higher mortality *** is the main cause of deaths due to burn *** research is required in order to generate awareness among government and community for reducing the number of injuries and burn deaths in our country.

关键词： injuries injury characteristics

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Current applications of artificial intelligence for intraoperative decision support in surgery Allison

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Frontiers of Medicine 2020年第4期14卷 369-381页

作者： J.navarrete-Welton Daniel A.Hashimoto Surgical Artificial Intelligence and Innovation Laboratory Massachusetts General HospitalBostonMA 02114USA Harvard Medical School BostonMA 02114USA

Research into medical artificial intelligence(AI)has made significant advances in recent years,including surgical *** scoping review investigated AI-based decision support systems targeted at the intraoperative phase of surgery and found a wide range of technological approaches applied across several surgical *** the twenty-one(n=21)included papers,three main categories of motivations were identified for developing such technologies:(1)augmenting the information available to surgeons,(2)accelerating intraoperative pathology,and(3)recommending surgical *** many of the proposals hold promise for improving patient outcomes,important methodological shortcomings were observed in most of the reviewed papers that made it difficult to assess the clinical significance of the reported performance *** limitations,the current state of this field suggests that a number of opportunities exist for future researchers and clinicians to work on AI for surgical decision support with exciting implications for improving surgical care.

关键词： artificial intelligence decision support clinical decision support systems intraoperative deep learning computer vision machine learning surgery

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Application of wave equation theory to improve dynamic cone penetration test for shallow soil characterisation

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Journal of Rock Mechanics and Geotechnical Engineering 2022年第1期14卷 289-302页

作者： Miguel Angel Benz navarrete Pierre Breul Roland Gourvès Sol Solution Géotechnique Réseaux ZA des Portes de Riom Nord23 Avenue Georges GershwinRiom Cedex63204France UniversitéClermont Auvergne Institut PascalUMR CNRS 6602Clermont-Ferrand63000France Polytech Clermont-Ferrand Campus des Cézeaux 2 Avenue Blaise PascalAubière Cedex63178France

Among the geotechnical in situ tests,the dynamic penetration test(DPT)is commonly used around the ***,DPT remains a rough technique and provides only one failure parameter:blow count or cone *** paper presents an improvement of the dynamic cone penetration test(DCPT)for soil characterisation based on the wave equation *** on an instrumented lightweight dynamic penetrometer driving with variable energy,the main process of the test involves the separation and reconstruction of the waves propagating in the rods after each blow and provides a dynamic cone load-penetration(DCLT)*** analytical methodology is used to analyse this curve and to estimate additional strength and deformation parameters of the soil:dynamic and pseudo-static cone resistances,deformation modulus and wave *** carried out in the laboratory on different specimens(wood,concrete,sand and clay)in an experimental sand pit and in the field demonstrated that the resulting DCLT curve is reproducible,sensitive and reliable to the test conditions(rod length,driving energy,etc.)as well as to the soil properties(nature,density,etc.).Obtained results also showed that the method based on shock polar analysis makes it possible to evaluate mechanical impedance and wave velocity of soils,as demonstrated by the comparisons with cone penetration test(CPT)and shear wave velocity measurements made in the *** technique improves the method and interpretation of DPT and provides reliable data for shallow foundation design.

关键词： In situ test Dynamic cone penetrometer P.A.N.D.A. Wave equation Wave decoupling Dynamic cone load-penetration(DCLT)curve

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Spatiotemporal patterns of burned areas,fire drivers,and fire probability across the equatorial Andes

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Journal of Mountain Science 2021年第4期18卷 952-972页

作者： Xavier ZAPATA-RiOS Carmen LOPEZ-FABARA Abigail navarrete Sandra TORRES-PAGUAY Miguel FLORES Department of Civil and Environmental Engineering Escuela Politecnica NacionalLadron de Guevara E11-253P.O.Box 17-01-2759QuitoEcuador Center for Research and Water Resources Studies(CIERHI) Escuela Politecnica NacionalLadron de Guevara E11-253P.O.Box 17-01-2759QuitoEcuador Faculty of Agricultural Sciences Universidad Central del EcuadorAv.UniversitariaP.O.Box 17-03-100QuitoEcuador Modeling Optimization and Inferential Statistics Group(MODES)Department of MathematicsEscuela Politecnica NacionalLadron de Guevara Ell-253P.O.Box 17-01-2759QuitoEcuador

Field-based fire studies in the equatorial Andes indicate that fires are strongly associated with biophysical and anthropogenic ***,fire controls and fire regimes at the regional scale remain ***,this paper describes spatial and temporal burned-area patterns,identifies biophysical and anthropogenic fire drivers,and quantifies fire probability across 6°of latitude and 3°of longitude in the equatorial *** spatial and temporal burned-area analysis was carried out based on 18 years(2001-2018)of the MCD64 A1 MODIS burned-area ***,topography,vegetation,and anthropogenic variables were integrated in a logistic regression model to identify the significance of explanatory variables and determine fire occurrence probability.A total of 5779 fire events were registered during the 18 years of this study,located primarily along the western cordillera of the Andes and spreading from North to ***-eight percent of these fires took place within two fire hotspots located in the northwestern and southwestern corners of the study ***-nine percent occurred during the second part of the year,between June and *** largest density of fires was primarily located on herbaceous vegetation and *** show that mean monthly temperature,precipitation and NDVI during the prefire season,the location of land cover classes such as forest and agriculture,distance to roads and urban areas,slope,and aspect were the most important determinants of spatial and temporal fire *** logistic regression model achieved a good accuracy in predicting fire probability(80%).Probability was higher in the southwestern and northern corners of the study area,and lower towards the north in the western and eastern piedmonts of the *** analysis contributes to the understanding of fires in mountains within the *** results here presented have the potential to contribute to fire management and control in the regi

关键词： MODIS MCD64A1 Spectral vegetation indices Pre-fire season NDVI and precipitation Remote sensing

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Prevalence and ecological factors affecting the distribution of plant-parasitic nematodes in Prunus groves in Spain

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Journal of Integrative Agriculture 2024年第2期23卷 566-589页

作者： Ilenia Clavero-Camacho Antonio Archidona-Yuste Carolina Cantalapiedra.navarrete Pablo Castillo Juan Emilio Palomares-Rius Institute for Sustainable Agriculture(IAS) Spanish National Research Council(CSIC)Córdoba 14004Spain Andalusian Institute of Agricultural and Fisheries Research and Training(IFAPA) Centro Alameda del ObispoCórdoba 14004Spain

A wide survey was conducted to study plant-parasitic nematodes(PPNs)associated with Prunus groves in *** research aimed to determine the prevalence and distribution of PPNs in Prunus groves,as well as the influence of explanatory variables describing soil,climate and agricultural management in structuring the variation of PPNs community composition.A total of 218 sampling sites were surveyed and 84 PPN species belonging to 32 genera were identified based of an integrative taxonomic *** species considered as potential limiting factors in Prunus production,such as Meloidogyne arenaria,***,***,Pratylenchus penetrans and ***,were identified in this *** soil physico-chemical(C,Mg,N,Na,OM,P,pH and clay,loamy sand and sandy loam texture classes),four climate(Bio04,Bio05,Bio13 and Bio14)and four agricultural management variables(grove-use history less than 10 years,irrigation,apricot seedling rootstock,and Montclar rootstock)were identified as the most influential variables driving spatial patterns of PPNs *** particular,younger plantations showed higher values for species richness and diversity indices than groves cultivated for more than 20 years with Prunus *** study increases the knowledge of the distribution and prevalence of PPNs associated with Prunus rhizosphere,as well as on the influence of explanatory variables driving the spatial structure PPNs communities,which has important implications for the successful design of sustainable management strategies in the future in this agricultural system.

关键词： nematodes Meloidogyne Pratylenchus Paratylenchus rootstock distribution soil grove-use almond peach

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Optimal Stochastic Pine Stands Harvest Rotation Policies

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Open Journal of Forestry 2015年第6期5卷 593-606页

作者： Eduardo navarrete Department of System Engineering Universidad de la Frontera Temuco Chile

A new Faustmann optimal rotation harvesting stands’ problem under Brown geometric price and Logistic and Gompertz wood stock, diffusions is presented. The optimal cut policies for the stochastic Faustmann model and the single harvest rotation or Vicksell model are evaluated in the case of a Chilean Radiata pine forest company. The company cut policy validates the Vicksell model, its optimal cut policies overestimate the company policy cut in 1.2%, in the Gompertz case, and underestimate it in 2.3%, in the Logistic case. The Faustmann optimal cut policies present a larger underestimation of the company cut policy in 10.1%, in the Gompertz case, and in 21.5%, in the Logistic case. The preference for shorter evaluation period that the company shows is due to the organizational risk that the forest economic sectors has in Chile.

关键词： Optimal Tree Cutting Faustmann Stochastic Formula Component Optimal Stopping Problem

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Production of Carbon Nanotubes and Hydrogen Catalyzed with Ni/MCM-41 Catalysts

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Green and Sustainable Chemistry 2012年第3期2卷 91-96页

作者： Zhiqi Wang Juan navarrete Dirección de Investigación y Posgrado Instituto Mexicano del Petróleo México City México The American School Foundation México City Mexico

Methane catalytic decomposition (MCD) over Ni/MCM-41 catalysts was tested in a microreactor to simultaneously produce hydrogen and carbon nanotubes (CNTs). The methane conversion reached 30% to 47% at a moderate temperature range from 400°C to 600°C and the catalytic activity of the catalysts remains stable during 500 min steam on time. CNTs were chiefly formed through tip-growth mode, due to the weak interaction between the metallic Ni and the support. Most of the Ni particles are located on the tip of the produced CNTs, which avoids rapid deactivation of the catalyst resulted from carbon encapsulation. Large Ni particles usually lead to the formation of CNTs with big diameter. During the reaction, the shape of Ni particles changed from pseudo-sphere to diamond-like. All the CNTs consist of multiple layer walls and are curved in certain degree.

关键词： Methane Catalytic Decomposition Hydrogen Carbon Nanotubes Catalysts Ni/MCM-41

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Keggin Structure and Surface Acidity of 12-Phosphotungstic Acid Grafted Zr-MCM-48 Mesoporous Molecular Sieves

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World Journal of Nano Science and Engineering 2012年第3期2卷 134-141页

作者： Zhiqi Wang Juan navarrete Dirección de Investigación y Posgrado Instituto Mexicano del Petróleo Eje Lázaro Cárdenas Norte No. 152 México D.F. Mexico The American School Foundation Bondojito No. 21 Col. Las Americas México D.F. Mexico

A zirconium modified MCM-48 mesoporous material was synthesized by surfactant-templated method. Surface grafting Zr-MCM-48 with tungstophosphoric acid led to a great enhancement of both the number of the Br?nsted acid sites and acidity strength in comparison with the bare support. At 100°C, the 30 wt% H3PW12O40/Zr-MCM-48 contained 174 μmol/g Br?nsted acid sites which were 14.5 times greater than that of Zr-MCM-48. The Keggin structure of the grafted heteropolyacid was rather stable after calcination at 400°C for 2 h, approximately 93.3% of Keggin structure in the dispersed heteropolyacid were remained without destruction but slightly distorted in some degree, as evidenced by FTIR characterization and 31P NMR-MAS analysis. This H3PW12O40/Zr-MCM-48 solid with three dimensional mesoporous system, large surface area and very strong Br?nsted acidity will be a promising catalyst for acid catalytic reactions.

关键词： Zr-MCM-48 Surface Acidity Heteropolyacid Spectroscopic Characterization

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Numerical Characterization of Harbor Oscillations in the Port of Ensenada, Mexico

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Open Journal of Marine Science 2016年第3期6卷 395-404页

作者： Carlos R. Torres-navarrete National Oceanographic Data Center Institute for Oceanological Research Autonomous University of Baja California Ensenada Mexico

A series of numerical experiments from a barotropic configuration of the General Curvilinear Ocean Model (GCOM) was conducted to analyze the response to infragravity (IG) waves of the Port of Ensenada, located within Bahia de Todos Santos (BTS), west coast of Mexico. Experiments with forcing frequencies f = 50?1 min?1, f = 30?1 min?1, f = 25?1 min?1 and f = 16.66?1 min?1 showed the expected increase of energy at the corresponding forcing frequency band and also the appearance of secondary peaks of energy at frequency bands f = 8.33?1 min?1 and f = 4.16?1 min?1 which were identified as modes f1 and f2;being the band at f = 16.66?1 min?1 the zeroth f0 mode. Maximum peak of spectral energy from the numerical experiments was found at frequency band f0 = 16.66?1 min?1 which agreed with the estimated maximum value of the amplification factor and with the T0 mode of oscillation of the port. Distribution of amplitudes inside PE for modes f0, f1 and f2 were also presented. Mode f0 represents a quarter-wave oscillation with amplitudes of the same sign;mode f1 has two nodal lines and mode f2 presents and additional one. Corresponding harbor currents were also calculated, they were in the range 20 - 160 cm?s?1. Finally, in order to elucidate the source of the external signals found in the spectral analysis of this study, the natural oscillation modes of the BTS were estimated. Although more studies are needed, BTS oscillation mode T2 = 16.82 min, was identified as the external forcing that excites larger oscillations within the port.

关键词： Harbor Oscillations Port of Ensenada Mexico Boundary-Fitted Grids Curvilinear Coordinates

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