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Machine learning applied to road safety modeling:A systematic literature review

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Journal of Traffic and Transportation Engineering(English Edition) 2020年第6期7卷 775-790页

作者： Philippe Barbosa silva Michelle Andrade Sara ferreira Department of Civil Engineering Goiano Federal Institute-Rio Verde CampusRio Verde 75901-970Brazil Department of Civil and Environmental Engineering University of BrasiliaBrasilia 70910-900Brazil Research Centre for Territory Transports and EnvironmentUniversity of PortoPorto 4200-465Portugal

Road safety modeling is a valuable strategy for promoting safe mobility,enabling the development of crash prediction models(CPM)and the investigation of factors contributing to crash *** modeling has traditionally used statistical techniques despite acknowledging the limitations of this kind of approach(specific assumptions and prior definition of the link functions),which provides an opportunity to explore alternatives such as the use of machine learning(ML)*** study reviews papers that used ML techniques for the development of CPM.A systematic literature review protocol was conducted,that resulted in the analysis of papers and their *** types of models were identified:crash frequency,crash classification by severity,and crash frequency and *** first is a regression problem,the second,a classificatory one and the third can be approached either as a combination of the preceding two or as a regression model for the expected number of crashes by severity *** main groups of techniques used for these purposes are nearest neighbor classification,decision trees,evolutionary algorithms,support-vector machine,and artificial neural *** last one is used in many kinds of approaches given the ability to deal with both regression and classification problems,and also multivariate response *** paper also presents the main performance metrics used to evaluate the models and compares the results,showing the clear superiority of the ML-based models over the statistical *** addition,it identifies the main explanatory variables used in the models,which shows the predominance of road-environmental aspects as the most important factors contributing to crash *** review fulfilled its objective,identifying the various approaches and the main research characteristics,limitations,and opportunities,and also highlighting the potential of the usage of ML in crash analyses.

关键词： Transportation engineering Road safety modeling Crash prediction Crash injury severity Machine learning Systematic literature review

NDRank: optimised parallel search for weather analogues

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Big Earth Data 2023年第2期7卷 276-297页

作者： David Martins Miguel ferreira João Nuno silva Instituto Superior Técnico Universidade de LisboaLisboaPortugal Caravela Energy Partners DarienConnecticutUSA Distributed Parallel and Secure Systems GroupINESC-ID LisboaLisboaPortugal

Global meteorology data are now widely used in various areas, but one of its applications, weather analogues, still require exhaustive searches on the whole historical data. We present two optimisations for the state-of-the-art weather analogue search algorithms: a parallelization and a heuristic search. The heuristic search (NDRank) limits of the final number of results and does initial searches on a lower resolution dataset to find candidates that, in the second phase, are locally validated. These optimisations were deployed in the Cloud and evaluated with ERA5 data from ECMWF. The proposed parallelization attained speedups close to optimal, and NDRank attains speedups higher than 4. NDRank can be applied to any parallel search, adding similar speedups. A substantial number of executions returned a set of analogues similar to the existing exhaustive search and most of the remaining results presented a numerical value difference lower than 0.1%. The results demonstrate that it is now possible to search for weather analogues in a faster way (even compared with parallel searches) with results with little to no error. Furthermore, NDRank can be applied to existing exhaustive searches, providing faster results with small reduction of the precision of the results.

关键词： Multidimensional arrays weather analogues search parallel computing algorithm optimisation

Siderophore-Producing Rhizobacteria as a Promising Tool for Empowering Plants to Cope with Iron Limitation in Saline Soils:A Review

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Pedosphere 2019年第4期29卷 409-420页

作者： Maria J.ferreira Helena silva Angela CUNHA Biology Department and Centre for Environmental and Marine Studies(CESAM) University of Aveiro Campus de Santigo

Iron(Fe) bioavailability to plants is reduced in saline soils;however, the exact mechanisms underlying this effect are not yet completely understood. Siderophore-expressing rhizobacteria may represent a promising alternative to chemical fertilizers by simultaneously tackling salt-stress effects and Fe limitation in saline soils. In addition to draught, plants growing in arid soils face two other major challenges: high salinity and Fe deficiency. Salinity attenuates growth, affects plant physiology, and causes nutrient imbalance,which is, in fact, one of the major consequences of saline stress. Iron is a micronutrient essential for plant development, and it is required by several metalloenzymes involved in photosynthesis and respiration. Iron deficiency is associated with chlorosis and low crop productivity. The role of microbial siderophores in Fe supply to plants and the effect of plant growth-promoting rhizobacteria(PGPR) on the mitigation of saline stress in crop culture are well documented. However, the dual effect of siderophore-producing PGPR, both on salt stress and Fe limitation, is still poorly explored. This review provides a critical overview of the combined effects of Fe limitation and soil salinization as challenges to modern agriculture and intends to summarize some indirect evidence that argues in favour of siderophore-producing PGPR as biofertilization agents in salinized soils. Recent developments and future perspectives on the use of PGPR are discussed as clues to sustainable agricultural practices in the context of present and future climate change scenarios.

关键词： aridity bioavailability biofertilizer Fe deficiency high salinity plant growth-promoting rhizobacteria(PGPR) saline stress soil salinization

A Rapid Parameter of Enzyme-Treated Cellulosic Material Revealed by Reducing Sugar Release

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Journal of Renewable Materials 2024年第3期12卷 539-551页

作者： Verônica Távilla ferreira silva Adriane Maria ferreira Milagres Departamento de Biotecnologia Escola de Engenharia de LorenaUniversidade de São PauloLorenaSP12602-810Brazil

This study was conducted to evaluate the effectiveness of enzymes in purifying and reducing the degree of polymerization of cellulose for the production of dissolving *** goal was to determine the contributions of xylanase(X)and endoglucanase(EG)in the treatment of pulp,specifically by quantifying the formation of soluble and insoluble reducing sugars using the dinitrosalycilic acid(DNS)***,the release of soluble reducing sugars(RSSol)was enhanced after xylanase treatment,while endoglucanase(EG)treatment led to changes in insoluble reducing sugars(RSIns).The maximum synergism was observed for RSIns when a high ratio of endoglucanase to xylanase(320EG:5X/g pulp)was *** relative contribution of endoglucanase to RSins was determined to be 15.6%of the total reducing *** viscosity of pulps treated with xylanase decreased only by 7%,whereas endoglucanase treatment significantly reduced viscosity by 45%.Modifications in the particle size were observed after pulp treatment with the combination of endoglucanase and *** summary,the DNS test is a rapid and effective method for evaluating the efficiency of enzyme treatments on *** measurement of RSIns correlates with changes in pulp viscosity to different extents,providing valuable insights into the effectiveness of enzyme treatments.

关键词： Endoglucanase xylanase cellulose fiber pulp synergism

Laser texturing of piston ring for tribological performance improvement

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Friction 2023年第10期11卷 1895-1905页

作者： Rita ferreira Óscar CARVALHO Luís SOBRAL Sandra CARVALHO Filipe silva CMEMS-UMinho University of MinhoGuimarães 4800058Portugal LABBELS-Associate Laboratory Guimarães 4800058Portugal CEMMPRE-Center for Mechanical Engineering Materials and ProcessesUniversity of CoimbraRua Luís Reis SantosCoimbra 3030-788Portugal MAHLE Componentes de MotoresS.A.Núcleo Industrial de MurtedeCantanhede 3060-372Portugal

The radial surface coating layer of compression piston rings is used to improve their wear resistance during the internal combustion engine ***,at top dead centers,the friction coefficient of the piston ring–cylinder liner pair is detrimental to the engine’s tribological *** this work,dimples with different texture dimensions and densities were tested in a home-developed *** friction coefficient was measured for all samples,and for those with the best results,their wear resistance was *** texture with an aspect ratio of 0.25 and a density area of 15%reported the best tribological results.

关键词： piston ring surface texture friction wear

Structural and optical properties of pillared Eu^(3+)-containing layered double hydroxides intercalated by 2-to 12-carbon aliphatic dicarboxylates

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Journal of Rare Earths 2022年第2期40卷 260-267,I0003页

作者： Alexandre Candido Teixeira Ivan Guide Nunes silva Alysson ferreira Morais Danilo Mustafa Physics Institute.University of Sao Paulo 05508-090Sao PauloSPBrazil

While the versatile composition of layered double hydroxides(LDHs)allows the introduction of almost any polyvalent cation in their structure,the exchangeable negatively charged ions intercalated between the plates increase their vast range of *** we report on the preparation and optical properties of pillared Eu^(3+)-substituted ZnAl LDHs intercalated by aliphatic dicarboxylates:-OOC-(CH_(2))_(n-2)-COO-.The basal distance in these materials is dependent on the size and packing of the intercalated *** varying the number(n)of carbon atoms in the aliphatic chain from 2 to 12,the interlayer gallery of these ZnAlEu LDHs is considerably expanded from 0.9 to 2.1 *** the interlayer gallery,the aliphatic dicarboxylates form a monolayer,with the aliphatic chain inclined by an angleα≈63°with the hydroxide *** carbon atom in the COO-group is 0.43 nm far from the metal plane,showing that these carboxylates are not grafted in the brucite-like *** LDHs are thermally stable up to around 150℃,after which dehydroxylation of the hydroxide layers is *** Judd-Ofelt intensity parameters were obtained and compared to the Eu^(3+)-containing complexes with the same ligand series indicating a more symmetrical and less polarizable chemical environment around the rare earth ion.

关键词： Europium Layered double hydroxides Carboxylate ligands Luminescence Rare earths

Spatial-temporal distribution of fatal yellowing in different oil palm genetic materials in eastern amazon

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Information Processing in Agriculture 2022年第3期9卷 365-377页

作者： Bruno Borella Anhe Artur Vinicius ferreira dos Santos Thiago Alan ferreira da silva Lana Leticia Barbosa de Carvalho Paulo Roberto silva Farias Universidade Federal Rural da Amazonia Geoestatistics Department66.077-830 BelemBrazil Universidade Federal Rural da Amazonia Entomology Department66.077-830 BelemBrazil

Oil palm (Elaeis guineensis Jacq.) is one of the agricultural crops with the greatest potentialfor vegetable oil production in Brazil. However, a disease of unknown etiology popularlyknown as Fatal Yellowin (FY) has caused damage to Brazilian farmers particularly in theeastern region of the Amazon. So, the objective of this study was to evaluate the spatialdependence of FY on three oil palm genotypes, grown for many years in an organic produc-tion system in the Amazon region. The study area had 4104 ha, divided into 139 plots. Ineach plot, the monthly incidence of disease was monitored forming a database. The num-ber of diseased plants per year, number of accumulated diseased plants, number of dis-eased plants per hectare, growth rate of diseased plants and incidence of accumulateddisease were evaluated. The results indicated spatial distribution of the variables adjustedto the gaussian, spherical and exponential models, with predominance of the first *** increases the purpose that FY is caused by biotic factors. The highest range achievedin the study was 2929 m indicating the susceptibility of the tested genotypes. Some plotsclose to the river had the highest incidence of the disease on the study, probably associatedwith higher soil moisture.

关键词： Elaeis guineensis Geostatiscal analysis Kriging Palm oil Spatial dependence

Microbiological assessment of street foods at the point of sale in Maputo(Mozambique)

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Food Quality and Safety 2021年第1期5卷 22-30页

作者： Acacio Salamandaneu Ana Carla silva Luisa Brito Manuel Malfeito-ferreira Linking Landscape EnvironmentAgriculture and Food(LEAF)Research CentreInstituto Superior de AgronomiaUniversity of LisbonLisbonPortugal Faculdade de Ciencias de Saude Universidade LurioBairro de MarrereNampulaMozambique

Objectives:The aim of this study was to assess the microbiological quality and safety of street food sold in the main streets and informal markets of Maputo,the capital of *** and Methods:From 83 different vendors selling different types of foods,83 samples of ready-to-eat(RTE)street food were ***,Escherichia coli and total coliforms were used as quality and hygiene *** monocytogenes(***)Salmonella and coagulase-positive staphylococc were used as food safety ***:High proportions of unsatisfactory food samples were found in both traditional hot(76.7%)and cold(75%)*** and Salmonella were tested negative in this ***,when coagulase-positive staphylococci was used as a food safety indicator,approximately 25%(23/83)of the food samples analyzed were classified as unsatisfactory/potentially ***:These results,showing that street food sold in Maputo clearly requires adequate sanitary conditions for its preparation and sale,contribute to the development of good manufacturing practices(GMP)for street food in Maputo,*** is the first report on the microbiological quality and safety of street food in Mozambique.

关键词： ready-to-eat street food Escherichia coli coagulase-positive staphylococcr good manufacturing practices good hygiene practices

Catalytic combustion of soot over ceria-zinc mixed oxides catalysts supported onto cordierite

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Journal of Environmental Sciences 2014年第3期26卷 694-701页

作者： Leandro Fontanetti Nascimento Renata Figueredo Martins Rodrigo ferreira silva Osvaldo Antonio Serra Department of Chemistry FFCLRP University of Sao Paulo

Modified substrates as outer heterogeneous catalysts was employed to reduce the soot generated from incomplete combustion of diesel or diesel/biodiesel blends, a process that harms the environment and public health. The unique storage properties of ceria （CeO2） makes it one of the most efficient catalysts available to date. Here, we proposed that ceria-based catalysts can lower the temperature at which soot combustion occurs; more specifically, from 610℃ to values included in the diesel exhausts operation range （300-450℃）. The sol-gel method was used to synthesize mixed oxide-based catalysts （CeO2：ZnO）; the resulting catalysts were deposited onto cordierite substrates. In addition, the morphological and structural properties of the material were evaluated by XRD, BET, TPR-H2, and SEM. Thermogravimetric （TG/DTA） analysis revealed that the presence of the catalyst decreased the soot combustion temperature by 200℃ on average, indicating that the oxygen species arise at low temperatures in this situation, promoting highly reactive oxidation reactions. Comparative analysis of soot emission by diffuse reflectance spectroscopy （DRS） showed that catalyst-impregnated cordierite samples efficiently oxidized soot in a diesel/biodiesel stationary motor： soot emission decreased by more than 70%.

关键词： soot oxidation mixed oxides ceria