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Interpolating Socioeconomic Data for the Analysis of Deforestation:A Comparison of Methods

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Journal of Geographic Information System 2012年第4期4卷 358-365页

作者： Michelle Farfán jean francois mas Laura Osorio Centro de Investigaciones en Geografía Ambiental Universidad Nacional Autonoma de MexicoMoreliaMexico

This study compares local-level socioeconomic variables interpolated with three different methods: 1) Thiessen polygons, 2) Inverse distance weighting, and 3) Areas of influence based on cost of distance. The main objective was to determine the interpolation technique capable of generating the most efficient variable to explain the distribution of deforestation through two statistical approaches: generalized linear models and hierarchical partition. The study was conducted in two regions of western Mexico: Coyuquilla River watershed, and the Sierra de Manantlan Biosphere Reserve (SMBR). For SMBR it was found that the Thiessen polygons and areas of influence were the techniques that interpolated variables with greatest explanatory power for the deforestation process, in Coyuquilla it was inverse distance weighting. These differences are related to the distribution and the spatial correlation of the values of the variables.

关键词： Interpolation Socioeconomic Variables Deforestation Hierarchical Partition

Analysis of Land Use and Land Cover Changes and Evaluation of Natural Generation and Potential Restoration Areas in the Mexican Huasteca Region

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Open Journal of Forestry 2014年第2期4卷 124-135页

作者： Carmelo Peralta-Rivero Carlos Contreras-Servín María G.Galindo-Mendoza jean-francois mas Caussel Marcos Algara-Siller Multidisciplinary Graduate Programme in Environmental Sciences Autonomous University of San Luis/Coordination for Innovation and the Application of Science and TechnologySan Luis PotosiMexico Institute of Geography National Autonomous University of MexicoMoreliaMexico Multidisciplinary Graduate Programme in Environmental Sciences Faculty of EngineeringEnvironmental EngineeringAutonomous University of San LuisSan Luis PotosiMexico

This study aims to analyze temporal changes in land use and land cover change (LUCC) as well as identify areas for natural regeneration and potential areas for forest restoration in the Huasteca region for the period from 1976 to 2007. Changes were quantified in numbers and, additionally, cartography was used to identify and map the main affected areas. Different models based on Geographic Information Systems (GIS) demonstrated that LUCC have occurred on an area of 11718.82 km2, representing 17.84% of the region’s surface. Agriculture and the growth of pasture could be identified as the main human-induced activities that have led to landscape modification. In addition, forest cover is affected by a deforestation rate which is higher than the national average. Further important changes include a change from natural land cover to non-original land cover, affecting an area of 4911.88 km2 in the period from 1976-1993, and an area of 1892.5 km2 in the period from 1993-2002. Smaller changes could be observed for the period from 1993-2002 with an affected area of 1029.78 km2. At the same time, a natural regeneration from nonoriginal to original land cover took place from 1976-1993 on an area of 1318.68 km2, and also on an area of 974.18 km2 between 1993 an 2002. The surface that underwent a natural regeneration of forest cover made up 1932.07 km2. At the same time, an area of 5739.29 km2 for potential forest restoration was identified. Drawing on GIS methods and techniques, the development of thematic maps for land use, land use and land cover changes for the years of analysis (1976-1993-2002-2007) proved to be very adequate for the evaluation and analysis of the land cover and land use change, in particular with regard to the decrease of natural vegetation cover.

关键词： Land User Land Cover Natural Regeneration Forest Restoration LUCC GIS Temporal Analysis Huasteca

Susceptibility to gravitational processes due to land cover change in the Río Chiquito-Barranca del Muerto subbasin(Pico De Orizaba Volcano, México)

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Journal of Mountain Science 2017年第12期14卷 2511-2526页

作者： alanis-anaya rocío marisol legorreta-paulin gabriel mas jean francois granados-ramirez guadalupe rebeca college of geography faculty of philosophy and lettersnational autonomus university of mexico(unam)Mexico City 04510Mexico department of physical geography institute of geographynational autonomus university of mexico(unam)Mexico City 04510Mexico center for research in environmental geography national autonomus university of mexico(unam)Mexico City 58190Mexico

instability associated Land cover change can lead to slope by accelerating erosive processes with agriculture, forestry, and infrastructure. The Rio Chiquito-Barranca del Muerto subbasin has experienced an increase in land cover change due to government programs and the establishment of agricultural and urban areas. The aim of this study was to provide a model to map the susceptibility to gravitational processes along sites where anthropogenic land cover change has occurred. The method was based on the stratification of the subbasin according to landforms and cartographic variables. These variables were used in a multi- criteria assessment to assign weights according to their contribution to the onset of new gravitationalprocesses. Those weights were used to create a susceptibility map based on a weighted linear sum. The accuracy of the resulting map was validated in an error matrix with a random stratified design based on susceptibility classes per landform. The results produced a map of areas with susceptibility to gravitational processes due to land cover change; this susceptibility is very high in the undifferentiated pyroclastic slope and limestone mountain, where it derives not only from anthropogenie effects on natural vegetation cover, but also from steep slopes, weathered materials, low apparent density, high erosivity, and previous gravitational processes. The results support other studies that concluded that loss of vegetation is a triggering factor in the formation of gravitational processes, but also show that excessive reforestation can increase gravitational processes.

关键词： Gravitational processes susceptibility Land cover change Multi-criteria assessment Pico de Orizaba volcano

Review of the development and uses of hard grade asphalts in France

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Journal of Road Engineering 2021年第1期1卷 73-79页

作者： jean-francois Corte Directorate of Transport Infrastructures Ministry of TransportLa Defense 92055France

Hard grade paving asphalts,i.e.,having a penetration at 25C lower than 25 mm/10,have experienced,in France,a significant development over the last forty years,linked to the development of high modulus asphalt concrete for rehabilitation then for new construction of road *** the first part,this paper provides a review of the evolution of asphalts in France over the past sixty years towards the use of harder penetration grades and a limitation of the evolution of the asphalt in the mixing plant to avoid early cracking of the *** recommendations in relation to climatic conditions are *** characteristics of different hard asphalts produced in France are presented including data on the effect of ageing tests rolling thin film oven test(RTFOT)and pressure ageing vessel(PAV).Hardening of hard asphalt after RTFOTþPAV is comparable to that of softer *** performance related to low temperature cracking is less which limits the use of plain hard asphalt in pavements subjected to severe winter conditions and requires polymer *** specifications for hard grade paving asphalts based on traditional empirical tests included in the European standard developed in the mid 2000s and the choices made in France are presented.A comparison of the specifications for hard grade paving asphalts in the European standards and of those proposed for China shows that the European specifications are more stringent as regards consistency and evolution after ageing tests.

关键词： Asphalt Hard grade Rheology Standard

Computation of Shock Profiles in Radiative Hydrodynamics

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Communications in Computational Physics 2009年第10期6卷 1118-1136页

作者： jean-francois Coulombel Pauline Lafitte CNRS Laboratoire Paul Painleve and Project Team SIMPAF INRIA FutursUniversite Lille 1Cite Scientifique59655 VILLENEUVE D’ASCQ CedexFrance Laboratoire Paul Painleve and Project Team SIMPAF INRIA Futurs Universite Lille 1Cite Scientifique59655 VILLENEUVE D’ASCQ CedexFrance

This article is devoted to the construction of a numerical scheme to solve the equations of radiative *** use this numerical procedure to compute shock profiles and illustrate some earlier theoretical results about their smoothness and monotonicity *** first consider a scalar toy model,then we extend our analysis to a more realistic system for the radiative hydrodynamics that couples the Euler equations and an elliptic equation.

关键词： Radiative transfer shock profiles Euler equations numerical profiles

Oil Strategies Benefits over Different Driving Cycles using Numerical Simulation

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Journal of Thermal Science 2017年第4期26卷 371-377页

作者： Hanna SARA David CHALET Mickael CORMERAIS jean-francois HETET Ecole Centrale de Nantes LHEEA lab.(ECN/CNRS)NantesFrance MANN+HUMMEL France LavalFrance

95 g/kin is the allowed quantity of CO2 emission normalized to NEDC to be set in 2020. In addition, NEDC will be replaced by more severe driving cycles and will be united worldwide. To respond to those criteria, automotive industries are working on every possible field. Thermal management has been proved to be effective in reducing fuel consumption. Cold start is a primordial reason of ovcrconsumption, as the engine highest efficiency is at its optimal temperature. At cold start, the engine＇s oil is at its lowest temperature and thus its higher viscosity level. A high viscosity oil generates more friction, which is one of the most important heat losses in the engine. In th/s paper, hot oil storage is studied. Numerical simulations on GT-suite model were done. The model consists of a 4-cylinder turbocharged Diesel engine using a storage volume of 1 liter of hot oil. Ambient temperature vari- ation were taken into consideration as well as different driving cycles. Furthermore, different configurations of the thermal strategy （multifunction oil sump） were proposed and evaluated. Lubricant temperature and viscosity profiles are presented in the article as well as fuel consumption savings for different configurations, driving cycles and ambient temperatures.

关键词： Thermal management Hot oil storage Oil sump Oil viscosity Fuel consumption

Simple Fabrication and Characterization of Discontinuous Carbon Fiber Reinforced Aluminum Matrix Composite for Lightweight Heat Sink Applications

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Acta Metallurgica Sinica(English Letters) 2014年第4期27卷 714-722页

作者： Hiroki Kurita Emilien Feuillet Thomas Guillemet jean-Marc Heintz Akira Kawasaki jean-francois Silvain DEN/DANS/DMN/SRMA/LTMEx CEA SaclayGif-sur-YvetteFrance Institute of Condensed Matter Chemistry of Bordeaux BordeauxFrance Department of Materials Processing Graduate School of EngineeringTohoku University

The constant increase in power and heat flux densities encountered in electronic devices fuels a rising demand for lightweight heat sink materials with suitable thermal *** this study,discontinuous pitch-based carbon fiber reinforced aluminum matrix（Al-CF） composites with aluminum–silicon alloy（Al–Si） were fabricated through hot *** small amount of Al–Si contributed to enhance the sintering process in order to achieve fully dense Al–CF composites.A thermal conductivity and CTE of 258 W/（m K） and 7.0 9 10-6/K in the in-plane direction of the carbon fibers were obtained for a（Al95 vol%＋ Al–Si5 vol%）-CF50 vol%*** fiber provides the reducing of CTE while the conservation of thermal conductivity and weight of *** achieved CTEs satisfy the standard requirements for a heat sink material,which furthermore possess a specific thermal conductivity of 109 W cm3/（m K g）.This simple process allows the low-cost fabrication of Al–CF composite,which is applicable for a lightweight heat sink material.

关键词： Carbon fiber Metal-matrix composites(MMCs) Thermal properties Powder processing

Multiplexing technology for in vitro diagnosis of pathogens： the key contribution of phosphorus dendrimers

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Science China Materials 2018年第11期61卷 1454-1461页

作者： jean Pierre Majoral jean Marie francois Richard Fabre Alice Senescau Serge Mignani Anne-Marie Caminade Laboratoire de Chimie de Coordination du CNRS 31077 Toulouse Cedex 4France LCC-CNRS Universit6 de Toulouse CNRSToulouseFrance Dendris 31670 LabegeFrance LISBP UMR CNRS 5504 INRA 79231077 Toulouse Cedex 04France Universite Paris Descartes PRES Sorbonne Paris Cite CNRS-UMR 860Laboratoire de Chimie et de Biochimie Pharmacologiques et Toxicolgique75006 ParisFrance

After the microbiology based on Pasteur's method and polymerase chain reaction(PCR), the diagnosis company named Dendris has proposed a third-generation of diagnosis enabling the search of a broad range of pathogens with strong sensitivity and specificity. This extraordinary profile was possible thanks to the use of phosphorus dendrimers for which various techniques of deposition on a given support were investigated and described and analyzed in this report.

关键词： phosphorus dendrimers diagnosis DNA arrays multiplexing technology

Differences in egg hatching time between cyclical and obligate parthenogenetic lineages of aphids

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Insect Science 2019年第1期26卷 135-141页

作者： Charles-Antoine Dedryver Joel Bonhomme jean-francois Le Gallic jean-Christophe Simon Unite Mixte de Recherche IGEPP 1349 INRAIAgrocampus OuestlUniversite Rennes 1Le Rheu cedexFrance

Many aphid species exhibit a variation in reproductive mode which is influenced by winter climate regimes,with cyclical parthenogenetic (CP)lines dominating in cold winter areas (because they produce cold-resistant eggs)and obligate parthenogenetic (OP) ones in mild winter regions (because of their parthenogenetic overwintering).Genetic studies on several aphid species have shown that the OP trait can be transmitted during sexual events involving the 2 types of *** genetic system could be considered as a local safeguarding mechanism for OP alleles in case severe frost would have killed all parthenogenetically overwintering ***,this strategy would only be efficient in restoring local polymorphism in breeding systems if the newly hatched OP recombinants remain competitive over their CP *** this study we compared egg hatching sequences of CP and OP F1 clones from several crosses obtained for 2 cereal aphid species,Sitobion avenae (constant 5℃,8 h of light)and Rhopalosiphum padi (winter outdoor conditions).For ***,we obtained F1 offspring from 6 crosses, involving 4 clones while in *** F1 were obtained from 11 crosses involving 14 clones. We showed that in both species proportions of OP clones were higher in the first half of the progeny relative to the second *** addition,F1 OP clones hatched in the mean about a week earlier than their CP sibs,which gives them a demographic advantage at the start of the growth *** then discussed the consequences of this fitness advantage for the maintenance and spread of the OP trait in aphid populations.

关键词： asexuality diapauses genetic variation insects overwintering strategies reproductive mode