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Krige Method Application for the Coverage Analysis of a Node-B in a WCDMA Network

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International Journal of Communications, Network and System Sciences 2011年第3期4卷 180-188页

作者： Jazmín Ponce-Rojas Sergio Vidal-Beltrán josé luis lópez-bonilla Montserrat Jimenez-licea 不详

This paper shows the procedure and application of the Krige Method (or Kriging) for the analysis of the power level radiated by a Base Station (also called Node B), through a group of samples of this power level, measured at different positions and distances. These samples were obtained using an spectrum analyzer, which will allow to have georeferenced measurements, to implement the interpolation process and generate coverage maps, making possible to know the power level distribution and therefore understand the behavior and performance of the Node B.

关键词： Interpolation Krige Node B WCDMA

Depth of closure:New calculation method based on sediment data

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International Journal of Sediment Research 2018年第2期33卷 198-207页

作者： luis Aragonés jose Ignacio Pagán Isabel lópez josé C.Serra Department of civil engineering University of Alicante Department of transportation ETSI Caminos Polytechnic University of Valencia

Obtaining depth of closure(DoC) in an accurate manner is a fundamental issue for coastal engineering,since good results for coastal structures and beach nourishment depend mainly on DoC. Currently, there are two methods for obtaining the DoC, mathematical formulations and profile surveys. However, these methods can incur important errors if one does not take into account the characteristics and morphology of the area, or if one does not have a sufficiently long time series. In this work the DoC is obtained from the break in the trend of the sediment with the depth, that is, in general with the increase of the depth a decrease in the size of the sediment takes place. However, at one point this tendency changes and the size increases, and then decreases again. When comparing the point where the minimum sediment size occurs before the increase, it is observed that the error incurred is small compared to other methods. If the Standard Deviation of Depth Change(SDDC) method is considered as the most accurate method, the error incurred by the proposed method is less than 7%. In addition, it can be seen that the dispersion of the sediment method always occurs outside the zone of bar movement. Whereas in the methods of profiles survey(using 2 cm precision profiles), sometimes the DoC is obtained within the active zone of bar movement. In addition, where the relative minimum of the median sediment size is found, and the sizes of 0.063 and 0.125 mm predominate in the composition of the sample. Therefore, this new method allows the precise location of the DoC to be obtained in a fast and simple way. Furthermore, this method has the advantage that it is not affected by the modifications that may be experienced by both the study area and the cross-shore beach profile.

关键词： Depth of Closure Median sediment size Profile surveys Profile change GIS

世界水土保持学会副主席,水土保持专家joséluis Rubio先生论森林火灾后土壤的保护与修复:生物工程的作用

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水土保持通报 2019年第1期39卷 310-316页

作者： josé luis Rubio 西班牙巴伦西亚大学沙漠化研究中心

[目的]讨论火灾地区土壤保护的基本方法,旨在从生物多样性和美学价值方面,阐述新兴生物工程领域在修复与固结土壤,保护土壤免遭不同类型侵蚀,维持景观质量等方面中的应用。[方法]通过综述和评价现行生物工程技术在西班牙森林火灾后土壤... 详细信息

[目的]讨论火灾地区土壤保护的基本方法,旨在从生物多样性和美学价值方面,阐述新兴生物工程领域在修复与固结土壤,保护土壤免遭不同类型侵蚀,维持景观质量等方面中的应用。[方法]通过综述和评价现行生物工程技术在西班牙森林火灾后土壤保持和土壤修复中的应用,阐述了有关基本原理,并介绍了一些生物工程技术在受火灾影响的不同地区的成功应用案例。[结果]生物工程技术用于森林火灾后土壤保护和修复的重要基础知识部分仍基于土壤保持的一些传统原理,尤其在与具体干预的立地和简单技术应用的生态一致性方面。同时也不应低估新近土木工程的作用。这些土木工程技术(包括金属笼的使用)为生物要素(主要是植物物质)发挥更大作用提供了条件,而这些生物要素是在特定干预区气候或生物物理条件下发挥固结土壤作用的重要因素。与活体材料一起使用的还有各种生物物质,例如植物残留物,砍下的灌木,木质化元素,以及多种土工织物。这些技术可以归结分为4组主要形式:(1)土壤保护技术,(2)地面稳定技术,(3)重建技术组合,(4)其他稳定技术。[结论]用于土壤保护的生物工程技术提供了一种更为环保和具有长期有效性的方法。它同时具有耗资低,适应性强和提供多功能景观效益等优势。然而,生物技术也存在一些缺陷,例如人力资源需求,缺乏有关知识和合适的植物物质,特别是在一些干旱气候地区。尽管如此,生物工程方法在满足森林火灾影响后土壤保护的紧急干预措施这类新需求过程中表现出其正在崛起,有应用前途和快速发展的态势。

关键词：森林火灾生物工程土壤保持与修复环境一致性

Channel Response to Gravel Mining Activities in Mountain Rivers

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Journal of Mountain Science 2004年第3期1卷 264-269页

作者： josé luis lópez S. Institute of Fluid Mechanics Faculty of EngineeringUniversidad Central de Venezuela. Caracas Venezuela.

s: The removal of bed material from active river channels usually affects the bed profile of the streambed, causing progressive degradation upstream and downstream of the extraction site. These effects can extend for kilometers affecting hydraulic structures located in the vicinity of the river reach. In this paper, the geomorphic effects of gravel mining are reviewed and summarized. Some cases in Venezuelan streams are presented to illustrate the problem. To describe the processes of erosion and sedimentation in a gravel extraction pit, a recent developed mathematical model for the simulation of flow and sediment transport in gravel-cobble bed streams is applied to a hypothetical case of gravel mining in a river channel. A simple rectangular dredge pit is imposed as initial condition in the channel bed, and changes in bed elevations and grain size distribution of bed material are calculated by using the numerical model. The process of deposition within the pit, and the downstream and upstream migration of the erosion wave are well simulated by the model and closely resemble the phenomena observed in laboratory experiments. The response of the friction coefficient to the changes in flow and bed elevations shows the importance in modeling adequately flow resistance and sediment transport in gravel-cobble bed streams.

关键词： Channel response gravel mining Venezuelan cases

A NEW APPROACH TO SOlVE SYSTEMS OF lINEAR EQUATIONS

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Journal of Computational Mathematics 2001年第4期19卷 445-448页

作者： V á squez, luis V á squez-Poletti, jos é l. Universidad Complutense 西班牙 E-28040 Universidad Pontificia Comillas 西班牙 E-28015

Presents a study which proposed an iterative approach to solve systems of linear equations. Definition of two families of convergent iterative methods; Features of the iterative method; Application of the method to a ... 详细信息

关键词： Iterative method linear systems Classical dynamics.

Camera traps reveal the natural corridors used by mammalian species in eastern Mexico

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Ecological Processes 2022年第1期11卷 711-722页

作者： Jonathan O.Huerta‑Rodríguez Octavio C.Rosas‑Rosas lauro lópez‑Mata josél.Alcántara‑Carbajal luis A.Tarango‑Arámbula Programa de Recursos Genéticos y Productividad‑Ganadería Colegio de Post‑graduadosCampus MontecilloTexcocoMexico Programa de Innovación en Manejo de Recursos Naturales Colegio de PostgraduadosCampus San Luis PotosíSan Luis PotosíMexico Programa de Dinámica y Conservación de Bosques y Selvas Macroecología y BiodiversidadColegio de PostgraduadosCampus MontecilloTexcocoMexico

Background:Habitat loss and fragmentation in the Sierra Madre Oriental(SMO)ecological corridor have negative impacts on the movement and distribution of mammalian species that are of great ecological and evolutionary *** of the SMO ecological corridor that is located in the state of Hidalgo is less studied despite being a potential dispersal route for *** objectives of this study were to evaluate the presence and activity of terrestrial mammals in the riparian and non‑riparian zones of ***:Camera traps detected 15 mammalian species(i.e.,14 native and 1 domestic)in the non‑riparian zone,and 12 mammalian species in the riparian zone(i.e.,10 wild and 2 domestic).The riparian corridor was mainly used by opportunistic medium‑sized carnivores,while large carnivores and their potential prey were more frequent in the non‑riparian ***:Our findings suggest terrestrial mammals avoid the use of natural corridors due to the presence of domestic dogs,cattle and humans and look for new dispersal routes to move through their habitat and find the resources they need to *** though some species can use disturbed corridors to move and find resources,they will change their activity patterns to avoid contact with humans and potential threats like *** is,therefore,crucial to identify not one,but several corridors that must be preserved to improve the connectivity of terrestrial mammals in disturbed landscapes.

关键词： Activity Jaguar Cattle Detectability Dog Herbivore Disturbance Prey Relative abundance

Multi-temporal NDVI analysis using UAV images of tree crowns in a northern Mexican pine-oak forest

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Journal of Forestry Research 2023年第6期34卷 1855-1867页

作者： joséluis Gallardo-Salazar Marcela Rosas-Chavoya Marín Pompa-García Pablito Marcelo lópez-Serrano Emily García-Montiel Arnulfo Meléndez-Soto Sergio Iván Jiménez-Jiménez Instituto de Investigaciones Agropecuarias y Forestales Universidad Michoacana de San Nicolás de Hidalgo(UMSNH)58330 MoreliaMichoacánMexico Programa Institucional de Doctorado en Ciencias Agropecuarias y Forestales Universidad Juárez del Estado de DurangoRío Papaloapan y Blvd.DurangoValle del Sur s/n34120 DurangoDurangoMéxico Facultad de Ciencias Forestales Universidad Juárez del Estado de DurangoRío Papaloapan y Blvd.DurangoValle del Sur s/n34120 DurangoDurangoMéxico Instituto de Silvicultura e Industria de la Madera Universidad Juárez del Estado de DurangoBoulevard del Guadiana 501Ciudad UniversitariaTorre de Investigación34120 DurangoMéxico INIFAP-CENID RASPA Centro Nacional de Investigación Disciplinaria en Relación Agua-Suelo-Planta-Atmósfera Margen derecha canal Sacramento km 6.5Zona industrial35140 Gómez PalacioDurangoMexico

The use of unmanned aerial vehicles(UAV)for forest monitoring has grown significantly in recent years,providing information with high spatial resolution and temporal *** with multispectral sensors allow the use of indexes such as the normalized difference vegetation index(NDVI),which determines the vigor,physiological stress and photo synthetic activity of *** study aimed to analyze the spectral responses and variations of NDVI in tree crowns,as well as their correlation with climatic factors over the course of one *** study area encompassed a 1.6-ha site in Durango,Mexico,where Pinus cembroides,Pinus engelmannii,and Quercus grisea *** images were acquired with UAV and information on meteorological variables was obtained from NASA/POWER *** ANOVA explored possible differences in NDVI among the three *** correlation was performed to identify the linear relationship between NDVI and meteorological *** differences in NDVI values were found at the genus level(Pinus and Quercus),possibly related to the physiological features of the species and their *** grisea had the lowest NDVI values throughout the year which may be attributed to its sensitivity to relative humidity and *** the use of UAV with a multispectral sensor for NDVI monitoring allowed genera differentiation,in more complex forest analyses hyperspectral and liDAR sensors should be integrated,as well other vegetation indexes be considered.

关键词： Multispectral images Normalized diff erence Vegetation index Phenology Unmanned aerial vehicles Multitemporal analysis

Glyphosate Dissipation in Different Soils Under No-Till and Conventional Tillage

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Pedosphere 2019年第6期29卷 773-783页

作者： Elena OKADA joséluis COSTA Francisco BEDMAR Consejo Nacional de Investigaciones Científicas y Técnicas(CONICET) Balcarce 7620(Argentina Estación Experimental Agropecuaria Balcarce Instituto Nacional de Tecnología Agropecuaria(INTA)Balcarce 7620(Argentina Facultad de Ciencias Agrarias Universidad Nacional de Mar del PlataBalcarce 7620(Argentina

Glyphosate is the most used herbicide in Argentina, accounting for 62% of the commercialized pesticides on the market. It is used as a weed controller in no-till systems, and it is also applied to various genetically modified crops ( e.g., soybean, corn, and cotton). Although it has a high solubility in water, it tends to adsorb and accumulate in agricultural soils. The main objectives of this work were to compare the dissipation of glyphosate and the accumulation of its metabolite aminomethylphosphonic acid (AMPA) over time in three soils from agricultural areas of Argentina under long-term management with no-till (NT) and conventional tillage (CT) practices. There were no differences in dissipation between NT and CT, indicating that the glyphosate-degrading microflora was not modified by the different tillage managements. Moreover, tillage practices did not alter the general soil properties;therefore, glyphosate bioavailability was not affected by NT or CT practice. Forty percent of the applied glyphosate was degraded within the first three days in all soils, indicating a fast initial dissipation rate. However, the dissipation rate considerably decreased over time, and the degradation kinetics followed a bi-exponential (or two-compartment) kinetic model. No differences were found between tillage practices. Dissipation was not related to the microbial activity measured as soil respiration. The fast decrease in the concentration of glyphosate at the beginning of the dissipation study was not reflected in an increase in the concentration of AMPA. The estimated half-lives for glyphosate ranged between 9 and 38 d. However, glyphosate bioavailability decreases over time, as it is strongly adsorbed to the soil matrix. This increases its residence time, which may lead to its accumulation in agricultural soils.

关键词： Aminomethylphosphonic acid Bioavailability Biodegradation Herbicide Metabolite Pesticide Two-compartment kinetic model

Sintering study of Ti6Al4V powders with different particle sizes and their mechanical properties

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International Journal of Minerals,Metallurgy and Materials 2018年第12期25卷 1389-1401页

作者： joséluis Cabezas-Villa josélemus-Ruiz Didier Bouvard Omar Jiménez Héctor Javier Vergara-Hernández luis Olmos University Michoacana of San Nicolás of Hidalgo IIMMMorelia 58060México University Grenoble Alpes CNRSSIMaPGrenoble 38000France University of Guadalajara Departamento de Ingeniería de ProyectosZapopan 45100México National Technological Institute of Mexico I.T.MoreliaMorelia 58120México University Michoacana of San Nicolás of Hidalgo INICITMorelia 58060México

Ti6Al4V powders with three different particle size distributions(0–20, 20–45, and 45–75 μm) were used to evaluate the effect of the particle size distribution on the solid-state sintering and their mechanical properties. The sintering kinetics was determined by dilatometry at temperatures from 900 to 1260°C. The mechanical properties of the sintered samples were evaluated by microhardness and compression tests. The sintering kinetics indicated that the predominant mechanism depends on the relative density irrespective of the particle size used. The mechanical properties of the sintered samples are adversely affected by increasing pore volume fraction. The elastic Young's modulus and yield stress follow a power law function of the relative density. The fracture behavior after compression is linked to the neck size developed during sintering, exhibiting two different mechanisms of failure: interparticle neck breaking and intergranular cracking in samples with relative densities below and above of 90%, respectively. The main conclusion is that relative density is responsible for the kinetics, mechanical properties, and failure behavior of Ti6 Al4 V powders.

关键词： Ti6Al4V powders dilatometry microhardness sintering kinetics compression failure behavior