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Fragmentation patterns and systematic transitions of the forested landscape in the upper Amazon region, Ecuador 1990-2008

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Journal of Forestry research 2014年第2期25卷 301-309页

作者： Santiago Bonilla-Bedoya juan r.molina José E.Macedo-Pezzopane Miguel A.Herrera-Machuca DepartaTento de Ingeniería Forestal E.T.S.I.A.M.Universidad de CórdobaCaTpus de Excelencia Internacional Agroali Tentario (ceiA3) Secretaria Nacional de Educación Superior CienciaTecnología e Innovación del EcuadorWhy Tper E7-37 y Alpallana Quito. Ecuador Departa Tento de Engenharia Florestal Universidade Federal do Espírito Santo

The analysis of the systematic transitions in the forested landscape and the study of the forest fragmentation patterns allow us to deepen our understanding of the changes in the vegetation ground cover. The importance of knowing the intricate patterns of the land usage of the upper basin of the Amazon region is widely recognized. This zone is one of the most diverse biological areas in the world, is home to large areas of mature tropical cloud forest and demonstrates high probabilities of stable climatic conditions in light of global warming. The research quan- tiffed systematic transitions through the ＂loss＂ and ＂gain＂ of the different categories of landscape during the eighteen-year study period of the Ecuadorian Amazon region （EAr）, the forest fragmentation patterns were also analyzed based on a set of indicators. Therefore, with respect to the entirety of the landscape, the results registered for the ground coverage in forested areas during the first period （1990-2000）, show a decrease of 6.99% and an increase of 0.68%; and during the second period （2000-2008）, show a decrease of 3.99% and an increase of 2.14%. It demonstrated that forest and agricultural areas tended to replace or be replaced by herbaceous vegetation faster than expected fortuitously. Finally, the indices of fragmentation signaled intense changes during the 1990-2000 period with a reduction during the period 2000-2008. Per- centages registered in the Largest Patch Index （LPI） were between 79.58%; 52.39% and 49.99% respectively; while the Patch Density （PD） varied between 0.04; 0.06 and 0.07. This suggests the propensity of for- est cover to remain intact. The results of this investigation suggest a tendency towards stability in Ecuador＇s Amazon landscape. Within the framework for development and management of this area, the tendency is natural regeneration. This permits a consolidation of the conservation, reforestation, forestation and agricultural forestry plans, programs and systems for the

关键词： Ecuadorian Amazon systematic transitions fragmentation natural regeneration

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On the unsteady motion and stability of a heaving airfoil in ground effect

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Acta Mechanica Sinica 2011年第2期27卷 164-178页

作者： juan molina David Angland School of Engineering Sciences University of Southampton Southampton SO17 1BJ UK

This study explores the fluid mechanics and force generation capabilities of an inverted heaving airfoil placed close to a moving ground using a UrANS solver with the Spalart-Allmaras turbulence model. By varying the mean ground clearance and motion frequency of the airfoil, it was possible to construct a frequency-height diagram of the various forces acting on the airfoil. The ground was found to enhance the downforce and reduce the drag with respect to freestream. The unsteady motion induces hysteresis in the forces’ behaviour. At moderate ground clearance, the hysteresis increases with frequency and the airfoil loses energy to the flow, resulting in a stabilizing motion. By analogy with a pitching motion, the airfoil stalls in close proximity to the ground. At low frequencies, the motion is unstable and could lead to stall flutter. A stall flutter analysis was undertaken. At higher frequencies, inviscid effects overcome the large separation and the motion becomes stable. Forced trailing edge vortex shedding appears at high frequencies. The shedding mechanism seems to be independent of ground proximity. However, the wake is altered at low heights as a result of an interaction between the vortices and the ground.

关键词： Oscillating airfoil · Flutter · Wing in ground effect · Vortex shedding

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Evaluating the influence of air pollution on solar radiation observations over the coastal region of Alicante(Southeastern Spain)

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Journal of Environmental Sciences 2023年第4期126卷 633-643页

作者： Igor Gómez Sergio molina juan JoséGaliana-Merino Department of Applied Physics Faculty of SciencesUniversity of AlicanteSection 99E-03080 AlicanteSpain Multidisciplinary Institute for Environmental Studies(MIES)“ramón Margalef” University of AlicanteSection 99E-03690 AlicanteSpain Department of Physics Systems Engineering and Signal TheoryUniversity of AlicanteSection 99E-03080 AlicanteSpain University Institute of Physics Applied to Sciences and Technologies University of AlicanteSection 99E-03080 AlicanteSpain

The present study evaluates ground-based downward surface shortwave radiation (rs) over the coastal region of Alicante (Southeastern Spain).Hourly measurements collected over the eleven-year period 2010-2020 are *** weather stations located over the region capital,Alicante,have been selected as representative of urban and suburban *** additional weather stations far from the city have been selected representing rural *** is significantly reduced over the urban station during the morning hours within the winter season compared to the observations recorded over the suburban and rural stations,with a global mean difference of-81 and-120 W/m^(2)at 10 LT,***,no significant differences are obtained during the midday sun,with a global mean difference of-20 W/m^(2)between the urban and rural *** the aim of explaining these differences,the current paper investigates the relationship between rsand different air pollutants:NOx,SO_(2),and fine particulate matter (PM_(2.5)and PM_(10)) as well as the wind field measured at the urban and suburban *** results found in this work point towards a close relationship between rsand NOxconcentrations annual cycles,which are also influenced by the prevailing wind circulations observed over the study area.A global mean NOxconcentration of 107μg/m^(3)is observed over the urban station at 10 LT during the winter *** contrast,these high concentrations are significantly reduced over the suburban station,with global mean value of 40μg/m^(3)at 10 LT,for this period of the year.

关键词： Solar radiation Air pollution Weather-concentration relationship Coastal cities Atmospheric conditions Wind field

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A NETWOrK ANALYSIS OF THE 2010 FIFA WOrLD CUP CHAMPION TEAM PLAY

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Journal of Systems Science & Complexity 2013年第1期26卷 21-42页

作者： COTTA Carlos MOrA Antonio M MErELO juan Julin MErELO-molina Cecilia Department of Computer Science University of Mlaga Department of Architecture and Computer Technology University of Granada

This paper analyzes the network of passes among the players of the Spanish team during the last FIFA World Cup 2010,where they emerged as the champion,with the objective of explaining the results obtained from the behavior at the complex network *** team is considered a network with players as nodes and passes as(directed) edges.A temporal analysis of the resulting passes network is also done,looking at the number of passes,length of the chain of passes,and to network measures such as player centrality and clustering *** of the last three matches(the decisive ones) indicate that the clustering coefficient of the pass network remains high,indicating the elaborate style of the Spanish *** effectiveness of the opposing team in negating the Spanish game is reflected in the change of several network measures over time,most importantly in drops of the clustering coefficient and passing length/speed,as well as in their being able in removing the most talented players from the central positions of the ***'s ability to restore their combinative game and move the focus of the game to offensive positions and talented players is shown to tilt the balance in favor of the Spanish team.

关键词： Complex network complex systems FIFA World Cup football La roja network analysis soccer Spanish team sports.

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Sustainable transit vehicle tracking service,using intelligent transportation system services and emerging communication technologies:A review

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Journal of Traffic and Transportation Engineering(English Edition) 2020年第6期7卷 729-747页

作者： ricardo Salazar-Cabrera álvaro Pachón de la Cruz juan Manuel Madrid molina Telematics Engineering research Group(GIT) Telematics DepartmentUniversidad del CaucaPopayanColombia Information Technology and Telecommunications research Group(I2T) ICT DepartmentUniuersidad IcesiCaliColombia

The most salient problems of transit vehicle service in Latin American intermediate cities include:the high number of passengers involved in traffic accidents;traffic congestion caused by transit vehicles,and pollution generated by these vehicles,which increases in high congestion *** improve upon this situation,a research was conducted on the transit vehicle tracking service,which is a basic service for implementing mobility solutions for the aforementioned problems,the most relevant characteristics of this service for the context of Latin American intermediate cities were identified,and an implementation was *** paper presents the four stages of the study:(a)a review of the state-of-the-art of services or systems related to vehicle tracking,including wireless communications technologies,implemented sustainability approaches,usage of special algorithms for efficiency improvement,and the intelligent transportation system(ITS)architecture used as a basis;(b)the process of identifying relevant characteristics of the service for a given context;(c)proposal of an ITS architecture for this service in an intermediate city,its requirements and the suggested technologies;and(d)development of experiments for validating usage of the key suggested *** review allowed to identify the main service characteristics,with regard to vehicle positioning technologies,the recommended wireless communication technology(long range,Lora),energy consumption considerations,and use of artificial intelligence(AI)to calculate waiting time of users at bus ***,an ITS architecture for the city of Popayan(Colombian city)considering the aforementioned characteristics is proposed,and the experiments related to the use of these technologies are described in detail.

关键词： Transportation engineering Intelligent transportation systems Transit vehicle ITS architecture Tracking Long range

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Intelligent collision risk detection in medium-sized cities of developing countries,using naturalistic driving:A review

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Journal of Traffic and Transportation Engineering(English Edition) 2022年第6期9卷 912-929页

作者： juan Jose Paredes Santiago Felipe Yepes ricardo Salazar-Cabrera Alvaro Pachon dela Cruz juan Manuel Madrid molina Telematics Engineering research Group(GIT) Telematics DepartmentUniversidad Del CaucaPopayanColombia Information Technology and Telecommunications research Group(12T) Universidad IcesiCaliColombia

Traffic accidents are one of the most serious problems worldwide,being one of the leading causes of death and economic loss in the ***-and middle-income countries,mainly their medium-sized cities,are among the most affected by this problem.93%of traffic accidents occur in low and middle-income countries,even though these countries have approximately 60%of the world’s *** occurs mainly because in these types of countries,especially in medium-sized cities(target context),there are no ideal conditions for driving,such as adequate road infrastructure,good condition of vehicles,and rigorous safety *** data analysis techniques including machine learning(ML)have increasingly been used to solve this *** driving(ND)can be applied as a data collection method that provides information on traffic *** commonly uses a vehicle’s kinematic data to detect high-risk driving behaviors that could cause an *** objectives of this document are to present a review of different alternatives that help in data collection and creation of intelligent solutions related to detection of possible traffic accidents,principally using ND;and to propose an intelligent collision risk detection system(ICrDS)for identification of areas with a high probability of TA in the target *** the review,it was possible to analyze and evaluate the devices,variables and algorithms that help characterize a risk event in driving,considering the target *** development of a prototype of an ICrDS for a medium-sized city in a developing country is considered viable,considering the identified components,with the aim of identifying risk events in driving,and areas of high probability of accidents in the city.

关键词： Naturalistic driving Near-crash Traffic accident Vehicle data collection

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Kinematic alterations after two high-intensity intermittent training protocols in endurance runners

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Journal of Sport and Health Science 2019年第5期8卷 442-449页

作者： Felipe García-Pinillos Alejandro molina-molina juan A.Párraga-Montilla Pedro A.Latorre-román Department of Corporal Expression University of JaenJaen 23071Spain Human Lab Sport and Health University Institute(iMUDS)Granada 18007Spain

Purpose:This study aimed to evaluate running kinematic characteristics during the early and late stages of 2 high-intensity intermittent training(HIIT)protocols with similar external load but different average running pace,as well as to compare the fatigue-induced changes during both HIIT protocols at a kinematic ***:Eighteen endurance runners were tested on a track on 2 occasions:10 runs of 400 m with 90-120 s recovery between running bouts(10 × 400 m),and 40 runs of 100 m with 25-30 s recovery between running bouts(40 × 100 m).Heart rate was monitored during both protocols;blood lactate accumulation and rate of perceived exertion were recorded after both exercises.A high-speed camera was used to measure sagittalplane kinematics at the first and last runs during both HIIT *** dependent variables were spatial-temporal parameters(step length and contact and flight time),joint angles during support(relative angles of the hip,knee,and ankle),and foot strike ***:High levels of exhaustion were reached by the athletes during both workouts(blood lactate accumulation>12 mmol/L,rate of perceived exertion>15;peak heart rate(Hrpeak)>176 bpm).A within-protocol paired t test(first *** run)revealed no significant changes(p≥0.05)in kinematic variables during any of the HIIT sessions.A between-protocol comparison with the first run of each protocol revealed the effect of running speed on kinematics:+2.44 km/h during the 40 × 100 m:shorter contact and flight time(pr step length(p= 0.001);greater hip flexion(p = 0.031)and ankle extension(p = 0.001)at initial contact;smaller knee and ankle flexion(preater hip extension at toe-off(pruns for 15-90 s and performed at intensity above the velocity associated with maximal oxygen uptake did not consistently perturb the running kinematics of trained endurance runners.

关键词： Biomechanics Fatigue-induced runners running Training Two-dimensional

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Experimental hybridization and reproductive isolation between two sympatric species of tephritid fruit flies in the Anastrepha fraterculus species group

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Insect Science 2018年第6期25卷 1045-1055页

作者： juan rull Eduardo Tadeo rodrigo Lasa Christian L.rodriguez Alma Altuzar.molina Martin Aluja PrOIMI Biotecnologia-OONICET LIEMEN-Division Control Biologico de PlagasTucumanArgentina red de Manejo Biorracional de Plagas y Vectores Instituto de EcologiaA.C.XalapaVeracruzMexico

Among tephritid fruit flies,hybridization has been found to produce local adaptation and speciation,and in the case of pest species,induce behavioral and ecological alterations that can adversely impact efficient pest *** species group within Anastrepha (Diptera:Tephritidae),is a rapidly radiating aggregate,which includes cryptic species complexes,numerous sister species,and several pest species. Molecular studies have highlighted the possibility of introgression between *** and *** isolation has been studied among morphotypes of the A. fraterculus species complex as a tool for species *** we examined the exis- tence and strength of prezygotic and postzygotic isolation between sympatric populations of two closely related species within the highly derivedfraterculus group (*** and ***),coexisting in *** adults of both species showed a strong tendency for assortative mating,a small proportion of hybrid pairings in both directions were *** also observed asymmetric postzygotic isolation,with one hybrid cross displaying a strong reduction in fecundity and F1 egg *** was greater for the progeny of homotypic and hybrid crosses in the maternal *** was a marked female biased sex ratio distortion for both F1 hybrid *** between *** and *** in nature may be difficult but possible;these two species display stronger reproductive isolation than all pairs of species previously examined in the *** species *** postzygotie isolation is suggestive of Wolbachia mediated cytoplasmic incompatibilities that may be exploited in area-wide pest management.

关键词： Anastrephafraterculus Anastrepha obliqua Haldane's rule introgression prezygotic isolation postzygotic isolation

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A multidimensional review of the cash management problem

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Financial Innovation 2023年第1期9卷 1840-1874页

作者： Francisco Salas‑molina juan A.rodríguez‑Aguilar Montserrat Guillen Universitat Politècnica de València Ferrándiz y Carbonell03801 AlcoySpain IIIA‑CSIC Campus UAB08913 CerdanyolaSpain Universitat de Barcelona Av.Diagonal69008034 BarcelonaSpain

In this paper,we summarize and analyze the relevant research on the cash manage-ment problem appearing in the ***,we identify the main dimensions of the cash management ***,we review the most relevant contributions in this field and present a multidimensional analysis of these contributions,according to the dimensions of the *** this analysis,several open research questions are highlighted.

关键词： Cash management Models Dimensions review

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Experimental control of optical helicity in nanophotonics

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Light(Science & Applications) 2014年第1期3卷 166-172页

作者： Nora Tischler Ivan Fernandez-Corbaton Xavier Zambrana-Puyalto Alexander Minovich Xavier Vidal Mathieu L juan Gabriel molina-Terriza ArC Centre for Engineered Quantum Systems Department of Physics&AstronomyMacquarie UniversitySydneyNSW 2109Australia Department of Physics&Astronomy Macquarie UniversitySydneyNSW 2109Australia Nonlinear Physics Centre and Centre for Ultrahigh-bandwidth Devices for Optical Systems(CUDOS) Research School of Physics and EngineeringThe Australian National UniversityCanberraACT 0200Australia

An analysis of light–matter interactions based on symmetries can provide valuable insight,particularly because it reveals which quantities are conserved and which ones can be transformed within a physical *** this context,helicity can be a useful addition to more commonly considered observables such as angular *** question arises how to treat helicity,the projection of the total angular momentum onto the linear momentum direction,in practical *** this paper,we put forward a simple but versatile experimental treatment of *** then apply the proposed method to the scattering of light by isolated cylindrical nanoapertures in a gold *** allows us to study the helicity transformation taking place during the interaction of focused light with the *** particular,we observe from the transmitted light that the scaling of the helicity transformed component with the aperture size is very different to the direct helicity component.

关键词： helicity nanoaperture nanophotonics optics symmetry

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