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Implication of community-level ecophysiological parameterization to modelling ecosystem productivity:a case study across nine contrasting forest sites in eastern China
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作者 Minzhe Fang Changjin Cheng +2 位作者 Nianpeng He Guoxin Si Osbert Jianxin Sun 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第1期1-11,共11页
Parameterization is a critical step in modelling ecosystem dynamics.However,assigning parameter values can be a technical challenge for structurally complex natural plant communities;uncertainties in model simulations... Parameterization is a critical step in modelling ecosystem dynamics.However,assigning parameter values can be a technical challenge for structurally complex natural plant communities;uncertainties in model simulations often arise from inappropriate model parameterization.Here we compared five methods for defining community-level specific leaf area(SLA)and leaf C:N across nine contrasting forest sites along the North-South Transect of Eastern China,including biomass-weighted average for the entire plant community(AP_BW)and four simplified selective sampling(biomass-weighted average over five dominant tree species[5DT_BW],basal area weighted average over five dominant tree species[5DT_AW],biomass-weighted average over all tree species[AT_BW]and basal area weighted average over all tree species[AT_AW]).We found that the default values for SLA and leaf C:N embedded in the Biome-BGC v4.2 were higher than the five computational methods produced across the nine sites,with deviations ranging from 28.0 to 73.3%.In addition,there were only slight deviations(<10%)between the whole plant community sampling(AP_BW)predicted NPP and the four simplified selective sampling methods,and no significant difference between the predictions of AT_BW and AP_BW except the Shennongjia site.The findings in this study highlights the critical importance of computational strategies for community-level parameterization in ecosystem process modelling,and will support the choice of parameterization methods. 展开更多
关键词 BIOME-BGC Community traits Forest Ecosystems Model parameterization
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An Optimized System of Random Forest Model by Global Harmony Search with Generalized Opposition-Based Learning for Forecasting TBM Advance Rate
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作者 Yingui Qiu Shuai Huang +3 位作者 Danial Jahed Armaghani Biswajeet Pradhan Annan Zhou Jian Zhou 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第3期2873-2897,共25页
As massive underground projects have become popular in dense urban cities,a problem has arisen:which model predicts the best for Tunnel Boring Machine(TBM)performance in these tunneling projects?However,performance le... As massive underground projects have become popular in dense urban cities,a problem has arisen:which model predicts the best for Tunnel Boring Machine(TBM)performance in these tunneling projects?However,performance level of TBMs in complex geological conditions is still a great challenge for practitioners and researchers.On the other hand,a reliable and accurate prediction of TBM performance is essential to planning an applicable tunnel construction schedule.The performance of TBM is very difficult to estimate due to various geotechnical and geological factors and machine specifications.The previously-proposed intelligent techniques in this field are mostly based on a single or base model with a low level of accuracy.Hence,this study aims to introduce a hybrid randomforest(RF)technique optimized by global harmony search with generalized oppositionbased learning(GOGHS)for forecasting TBM advance rate(AR).Optimizing the RF hyper-parameters in terms of,e.g.,tree number and maximum tree depth is the main objective of using the GOGHS-RF model.In the modelling of this study,a comprehensive databasewith themost influential parameters onTBMtogetherwithTBM AR were used as input and output variables,respectively.To examine the capability and power of the GOGHSRF model,three more hybrid models of particle swarm optimization-RF,genetic algorithm-RF and artificial bee colony-RF were also constructed to forecast TBM AR.Evaluation of the developed models was performed by calculating several performance indices,including determination coefficient(R2),root-mean-square-error(RMSE),and mean-absolute-percentage-error(MAPE).The results showed that theGOGHS-RF is a more accurate technique for estimatingTBMAR compared to the other applied models.The newly-developedGOGHS-RFmodel enjoyed R2=0.9937 and 0.9844,respectively,for train and test stages,which are higher than a pre-developed RF.Also,the importance of the input parameters was interpreted through the SHapley Additive exPlanations(SHAP)method,and it was found that thrust force per cutter is the most important variable on TBMAR.The GOGHS-RF model can be used in mechanized tunnel projects for predicting and checking performance. 展开更多
关键词 Tunnel boring machine random forest GOGHS optimization PSO optimization GA optimization ABC optimization SHAP
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Eff ects of thinning on ecosystem carbon storage and tree-shrub-herb diversity of a low-quality secondary forest in NE China 被引量:1
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作者 Baoshan Zhang Xibin Dong +2 位作者 Hangfeng Qu Ran Gao Liangliang Mao 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第4期977-991,共15页
Thinning is a widely used forest management tool but systematic research has not been carried out to verify its eff ects on carbon storage and plant diversity at the ecosystem level.In this study,the eff ect of thinni... Thinning is a widely used forest management tool but systematic research has not been carried out to verify its eff ects on carbon storage and plant diversity at the ecosystem level.In this study,the eff ect of thinning was assessed across seven thinning intensities(0,10,15,20,25,30 and 35%)in a low-quality secondary forest in NE China over a ten-year period.Thinning aff ected the carbon storage of trees,and shrub,herb,and soil layers(P<0.05).It fi rst increased and then decreased as thinning intensity increased,reaching its maximum at 30%thinning.Carbon storage of the soil accounted for more than 64%of the total carbon stored in the ecosystem.It was highest in the upper 20-cm soil layer.Thinning increased tree species diversity while decreasing shrub and herb diversities(P<0.05).Redundancy analysis and a correlation heat map showed that carbon storage of tree and shrub layers was positively correlated with tree diversity but negatively with herb diversity,indicating that the increase in tree diversity increased the carbon storage of natural forest ecosystems.Although thinning decreased shrub and herb diversities,it increased the carbon storage of the overall ecosystem and tree species diversity of secondary forest.Maximum carbon storage and the highest tree diversity were observed at a thinning intensity of 30%.This study provides evidence for the ecological management of natural and secondary forests and improvement of ecosystem carbon sinks and biodiversity. 展开更多
关键词 THINNING Carbon storage Plant diversity Forest management NE China
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Forest use suitability:Towards decision-making-oriented sustainable management of forest ecosystem services 被引量:1
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作者 Goran Krsnik Keith MReynolds +3 位作者 Philip Murphy Steve Paplanus Jordi Garcia-Gonzalo JoséRamón González Olabarria 《Geography and Sustainability》 CSCD 2023年第4期414-427,共14页
Management of forest lands considering multi-functional approaches is the basis to sustain or enhance the provi-sion of specific benefits,while minimizing negative impacts to the environment.Defining a desired managem... Management of forest lands considering multi-functional approaches is the basis to sustain or enhance the provi-sion of specific benefits,while minimizing negative impacts to the environment.Defining a desired management itinerary to a forest depends on a variety of factors,including the forest type,its ecological characteristics,and the social and economic needs of local communities.A strategic assessment of the forest use suitability(FUS)(namely productive,protective,conservation-oriented,social and multi-functional)at regional level,based on the provision of forest ecosystem services and trade-offs between FUS alternatives,can be used to develop management strategies that are tailored to the specific needs and conditions of the forest.The present study assesses the provision of multiple forest ecosystem services and employs a decision model to identify the FUS that sup-ports the most present and productive ecosystem services in each stand in Catalonia.For this purpose,we apply the latest version of the Ecosystem Management Decision Support(EMDS)system,a spatially oriented decision support system that provides accurate results for multi-criteria management.We evaluate 32 metrics and 12 as-sociated ecosystem services indicators to represent the spatial reality of the region.According to the results,the dominant primary use suitability is social,followed by protective and productive.Nevertheless,final assignment of uses is not straightforward and requires an exhaustive analysis of trade-offs between all alternative options,in many cases identifying flexible outcomes,and increasing the representativeness of multi-functional use.The assignment of forest use suitability aims to significantly improve the definition of the most adequate management strategy to be applied. 展开更多
关键词 Forest ecosystem services Decision making Forest use suitability Multi-objective management Geospatial analysis
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Structural Damage Identification System Suitable for Old Arch Bridge in Rural Regions: Random Forest Approach 被引量:1
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作者 Yu Zhang Zhihua Xiong +2 位作者 Zhuoxi Liang Jiachen She Chicheng Ma 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第7期447-469,共23页
A huge number of old arch bridges located in rural regions are at the peak of maintenance.The health monitoring technology of the long-span bridge is hardly applicable to the small-span bridge,owing to the absence of ... A huge number of old arch bridges located in rural regions are at the peak of maintenance.The health monitoring technology of the long-span bridge is hardly applicable to the small-span bridge,owing to the absence of technical resources and sufficient funds in rural regions.There is an urgent need for an economical,fast,and accurate damage identification solution.The authors proposed a damage identification system of an old arch bridge implemented with amachine learning algorithm,which took the vehicle-induced response as the excitation.A damage index was defined based on wavelet packet theory,and a machine learning sample database collecting the denoised response was constructed.Through comparing three machine learning algorithms:Back-Propagation Neural Network(BPNN),Support Vector Machine(SVM),and Random Forest(R.F.),the R.F.damage identification model were found to have a better recognition ability.Finally,the Particle Swarm Optimization(PSO)algorithm was used to optimize the number of subtrees and split features of the R.F.model.The PSO optimized R.F.model was capable of the identification of different damage levels of old arch bridges with sensitive damage index.The proposed framework is practical and promising for the old bridge’s structural damage identification in rural regions. 展开更多
关键词 Old arch bridge damage identification machine learning random forest particle swarm optimization
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Tree-based ecosystem services supply and multifunctionality of church forests and their agricultural matrix near Lake Tana,Ethiopia
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作者 Ferehiwot Mequanint Tobias Fremout +7 位作者 Diederik Strubbe Alemayehu Wassie Shimelis Aynalem Enyew Adgo Jan Nyssen Amaury Frankl Luc Lens Bart Muys 《Forest Ecosystems》 SCIE CSCD 2023年第6期656-667,共12页
Ecosystem services(ES)are the connection between nature and society,and are essential for the well-being of local communities that depend on them.In Ethiopia,church forests and the surrounding agricultural matrix supp... Ecosystem services(ES)are the connection between nature and society,and are essential for the well-being of local communities that depend on them.In Ethiopia,church forests and the surrounding agricultural matrix supply numerous ES.However,the ES delivered by both land use types have not yet been assessed simultaneously.Here we surveyed both church forests and their agricultural matrices,aiming to quantify,compare and unravel the drivers underlying tree-based ES supply,density and multifunctionality.We found that almost all church forests and half of the agricultural matrices provided high ES densities.ES multifunctionality was higher in the agricultural matrices,suggesting that people deliberately conserve or plant multifunctional tree species.Furthermore,the supply of all categories of ES was positively correlated with church forest age(p-value<0.001)in the agricultural matrix,while the extent of church forest was positively correlated with the density of all categories ecosystem services score in the church forests(p-value<0.001).Our results can be used to prioritize conservation efforts at sites that provide high levels of ES supply,ES density and ES multifunctionality,and to prioritize restoration efforts at sites with low levels thereof. 展开更多
关键词 Church forest Remnant forest Provisioning service Regulating service Cultural service Multifunctionality Key informant interview Agricultural matrix
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Impact of invasive Ageratina adenophora on relative performance of woody vegetation in different forest ecosystems of Kumaun Himalaya,India
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作者 Bhawna NEGI Kavita KHATRI +3 位作者 Surendra S.BARGALI Kiran BARGALI Archana FARTYAL R.K.CHATURVEDI 《Journal of Mountain Science》 SCIE CSCD 2023年第9期2557-2579,共23页
Invasive plant Ageratina adenophora(Sprengel)R.King&H.Robinson has invaded majority of the temperate forests in Kumaun,Central Himalaya.Information on A.adenophora invaded forest types,their structural attributes,... Invasive plant Ageratina adenophora(Sprengel)R.King&H.Robinson has invaded majority of the temperate forests in Kumaun,Central Himalaya.Information on A.adenophora invaded forest types,their structural attributes,population demography and regeneration status are still at rudimentary level.Considering this,the present study was conducted to assess the impacts of A.adenophora on vegetational attributes and regeneration status of three forest types,viz.,Oak(Quercus oblongata D.Don),Pine(Pinus roxburghii Sarg.)and Cypress(Cupressus torulosa D.Don).We selected three sites for each forest type and each site was further purposively stratified into paired sampling plots of 1 ha each i.e.,A.adenophora invaded and uninvaded sites.Our results showed large densities of cut stumps or felled trees throughout invaded sites,but with fewer fire signs in comparison to uninvaded sites.In uninvaded sites,total density and basal area calculated for woody species were relatively higher than those in invaded sites,although results were insignificant(p>0.05).With the exception for Cypress forests,vegetation indices showed low woody species richness and diversity in invaded Oak and Pine forests.Also,regeneration of Q.oblongata,P.roxburghii and C.torulosa tree species did not differ significantly(p>0.05)between invaded and uninvaded sites.These insignificant differences clearly imply that A.adenophora's presence has not entirely changed the perennial plant communities in terms of composition,structure and natural regeneration.However,tree species with poor or no regeneration status requires special attention and needs management strategies involving control of invasive species in forest ecosystems. 展开更多
关键词 Ageratina adenophora Seedling density FORESTS Population structure REGENERATION
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Mapping cultural ecosystem services in mountain forests using mobile phone data
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作者 CIESIELSKI Mariusz KAMINSKA Agnieszka 《Journal of Mountain Science》 SCIE CSCD 2023年第12期3437-3449,共13页
The aim of the work was to determine the spatial distribution of activity in the forest on the area of the Forest Promotional Complex“Sudety Zachodnie”using mobile phone data.The study identified the sites with the ... The aim of the work was to determine the spatial distribution of activity in the forest on the area of the Forest Promotional Complex“Sudety Zachodnie”using mobile phone data.The study identified the sites with the highest(hot spot)and lowest(cold spot)use.Habitat,stand,demographic,topographic and spatial factors affecting the distribution of activity were also analyzed.Two approaches were applied in our research:global and local Moran’s coefficients,and a machine learning technique,Boosted Regression Trees.The results show that 11,503,320 visits to forest areas were recorded in the“Sudety Zachodnie”in 2019.The most popular season for activities was winter,and the least popular was spring.Using global and local Moran’s I coefficients,three small hot clusters of activity and one large cold cluster were identified.Locations with high values with similar neighbours(hot-spots)were most often visited forest areas,averaging almost 200,000 visits over 2019.Significantly fewer visits were recorded in cold-spots,the average number of visits to these areas was about 4,500.The value of global Moran’s I was equal to 0.54 and proved significant positive spatial autocorrelation.Results of Boosted Regression Trees modeling of visits in forest,using tree stand habitat and spatial factors accurately explained 76%of randomly selected input data.The variables that had the greatest effect on the distribution of activities were the density of hiking and biking trails and diversity of topography.The methodology presented in this article allows delineation of Cultural Ecosystem Services hot spots in forest areas based on mobile phone data.It also allows the identification of factors that may influence the distribution of visits in forests.Such data are important for managing forest areas and adapting forest management to the needs of society while maintaining ecosystem stability. 展开更多
关键词 Ecosystem services Big data Traffic research MONITORING FORESTS
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Assessing fire severity in Turkey's forest ecosystems using spectral indices from satellite images
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作者 Coşkun Okan Güney Ahmet Mert Serkan Gülsoy 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第6期1747-1761,共15页
Fire severity classifications determine fire damage and regeneration potential in post-fire areas for effective implementation of restoration applications.Since fire damage varies according to vegetation and fire char... Fire severity classifications determine fire damage and regeneration potential in post-fire areas for effective implementation of restoration applications.Since fire damage varies according to vegetation and fire characteristics,regional assessment of fire severity is crucial.The objectives of this study were:(1)to test the performance of different satellite imagery and spectral indices,and two field—measured severity indices,CBI(Composite Burn Index)and GeoCBI(Geometrically structured Composite Burn Index)to assess fire severity;(2)to calculate classification thresholds for spectral indices that performed best in the study areas;and(3)to generate fire severity maps that could be used to determine the ecological impact of forest fires.Five large fires in Pinus brutia(Turkish pine)and Pinus nigra subsp.pallasiana var.pallasiana(Anatolian black pine)—dominated forests during 2020 and 2021 were selected as study sites.The results show that GeoCBI provided more reliable estimates of field—measured fire severity than CBI.While Sentinel-2 and Landsat-8/OLI images performed similarly well,MODIS performed poorly.Fire severity classification thresholds were determined for Sentinel-2 based RdNBR,dNBR,dSAVI,dNDVI,and dNDMI and Landsat-8/OLI based dNBR,dNDVI,and dSAVI.Among several spectral indices,the highest accuracy for fire severity classification was found for Sentinel-2 based RdNBR(72.1%)and Landsat-8/OLI based dNBR(69.2%).The results can be used to assess and map fire severity in forest ecosystems similar to those in this study. 展开更多
关键词 Remote sensing Forest fire Fire severity Spectral indices Composite burn index
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IOT Based Smart Parking System Using Ensemble Learning
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作者 Walaa H.Elashmawi Ahmad Akram +4 位作者 Mohammed Yasser Menna Hisham Manar Mohammed Noha Ihab Ahmed Ali 《Intelligent Automation & Soft Computing》 SCIE 2023年第6期3637-3656,共20页
Parking space is usually very limited in major cities,especially Cairo,leading to traffic congestion,air pollution,and driver frustration.Existing car parking systems tend to tackle parking issues in a non-digitized m... Parking space is usually very limited in major cities,especially Cairo,leading to traffic congestion,air pollution,and driver frustration.Existing car parking systems tend to tackle parking issues in a non-digitized manner.These systems require the drivers to search for an empty parking space with no guaran-tee of finding any wasting time,resources,and causing unnecessary congestion.To address these issues,this paper proposes a digitized parking system with a proof-of-concept implementation that combines multiple technological concepts into one solution with the advantages of using IoT for real-time tracking of park-ing availability.User authentication and automated payments are handled using a quick response(QR)code on entry and exit.Some experiments were done on real data collected for six different locations in Cairo via a live popular times library.Several machine learning models were investigated in order to estimate the occu-pancy rate of certain places.Moreover,a clear analysis of the differences in per-formance is illustrated with the final model deployed being XGboost.It has achieved the most efficient results with a R^(2) score of 85.7%. 展开更多
关键词 IOT XGBoost linear regression random forest ensemble learning isolation forest
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Spatial-temporal variations and driving factors of soil organic carbon in forest ecosystems of Northeast China
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作者 Shuai Wang Bol Roland +4 位作者 Kabindra Adhikari Qianlai Zhuang Xinxin Jin Chunlan Han Fengkui Qian 《Forest Ecosystems》 SCIE CSCD 2023年第2期141-152,共12页
Forest soil carbon is a major carbon pool of terrestrial ecosystems,and accurate estimation of soil organic carbon(SOC)stocks in forest ecosystems is rather challenging.This study compared the prediction performance o... Forest soil carbon is a major carbon pool of terrestrial ecosystems,and accurate estimation of soil organic carbon(SOC)stocks in forest ecosystems is rather challenging.This study compared the prediction performance of three empirical model approaches namely,regression kriging(RK),multiple stepwise regression(MSR),random forest(RF),and boosted regression trees(BRT)to predict SOC stocks in Northeast China for 1990 and 2015.Furthermore,the spatial variation of SOC stocks and the main controlling environmental factors during the past 25 years were identified.A total of 82(in 1990)and 157(in 2015)topsoil(0–20 cm)samples with 12 environmental factors(soil property,climate,topography and biology)were selected for model construction.Randomly selected80%of the soil sample data were used to train the models and the other 20%data for model verification using mean absolute error,root mean square error,coefficient of determination and Lin's consistency correlation coefficient indices.We found BRT model as the best prediction model and it could explain 67%and 60%spatial variation of SOC stocks,in 1990,and 2015,respectively.Predicted maps of all models in both periods showed similar spatial distribution characteristics,with the lower SOC in northeast and higher SOC in southwest.Mean annual temperature and elevation were the key environmental factors influencing the spatial variation of SOC stock in both periods.SOC stocks were mainly stored under Cambosols,Gleyosols and Isohumosols,accounting for 95.6%(1990)and 95.9%(2015).Overall,SOC stocks increased by 471 Tg C during the past 25 years.Our study found that the BRT model employing common environmental factors was the most robust method for forest topsoil SOC stocks inventories.The spatial resolution of BRT model enabled us to pinpoint in which areas of Northeast China that new forest tree planting would be most effective for enhancing forest C stocks.Overall,our approach is likely to be useful in forestry management and ecological restoration at and beyond the regional scale. 展开更多
关键词 Soil organic carbon stocks Forest ecosystem Spatial-temporal variation Carbon sink Digital soil mapping
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Identification of Mixtures of Two Types of Body Fluids Using the Multiplex Methylation System and Random Forest Models
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作者 Han-xiao WANG Xiao-zhao LIU +3 位作者 Xi-miao HE Chao XIAO Dai-xin HUANG Shao-hua YI 《Current Medical Science》 SCIE CAS 2023年第5期908-918,共11页
Objective Body fluid mixtures are complex biological samples that frequently occur in crime scenes,and can provide important clues for criminal case analysis.DNA methylation assay has been applied in the identificatio... Objective Body fluid mixtures are complex biological samples that frequently occur in crime scenes,and can provide important clues for criminal case analysis.DNA methylation assay has been applied in the identification of human body fluids,and has exhibited excellent performance in predicting single-source body fluids.The present study aims to develop a methylation SNaPshot multiplex system for body fluid identification,and accurately predict the mixture samples.In addition,the value of DNA methylation in the prediction of body fluid mixtures was further explored.Methods In the present study,420 samples of body fluid mixtures and 250 samples of single body fluids were tested using an optimized multiplex methylation system.Each kind of body fluid sample presented the specific methylation profiles of the 10 markers.Results Significant differences in methylation levels were observed between the mixtures and single body fluids.For all kinds of mixtures,the Spearman’s correlation analysis revealed a significantly strong correlation between the methylation levels and component proportions(1:20,1:10,1:5,1:1,5:1,10:1 and 20:1).Two random forest classification models were trained for the prediction of mixture types and the prediction of the mixture proportion of 2 components,based on the methylation levels of 10 markers.For the mixture prediction,Model-1 presented outstanding prediction accuracy,which reached up to 99.3%in 427 training samples,and had a remarkable accuracy of 100%in 243 independent test samples.For the mixture proportion prediction,Model-2 demonstrated an excellent accuracy of 98.8%in 252 training samples,and 98.2%in 168 independent test samples.The total prediction accuracy reached 99.3%for body fluid mixtures and 98.6%for the mixture proportions.Conclusion These results indicate the excellent capability and powerful value of the multiplex methylation system in the identification of forensic body fluid mixtures. 展开更多
关键词 body fluid identification MIXTURE mixing ratio DNA methylation multiplex assay random forest model
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Fungal diversity and community composition responses to the reintroduction of fire in a non-managed Mediterranean shrubland ecosystem
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作者 Juncal Espinosa Tatek Dejene +3 位作者 Mercedes Guijarro Xim Cerdá Javier Madrigal Pablo Martín-Pinto 《Forest Ecosystems》 SCIE CSCD 2023年第2期268-278,共11页
Background:More than a decade of fire suppression has changed the structure of fire-adapted shrubland ecosystems in Spain’s National Parks,which are now at extreme risk of uncontrolled wildfires.Prescribed burning ca... Background:More than a decade of fire suppression has changed the structure of fire-adapted shrubland ecosystems in Spain’s National Parks,which are now at extreme risk of uncontrolled wildfires.Prescribed burning can mitigate the risk of wildfires by reducing the fuel load but prescribed burning may also alter the soil properties and reduce microbial and fungal activity,causing changes in the availability of nutrients deep in the soil layer.Although fungal communities are a vital part of post-fire restoration,some fire effects remain unclear.To examine the short-term effects of prescribed burning on soil fungal communities in Doñana Biological Reserve(SW Spain),we collected soil samples pre-burn and 1 day,6 and 12 months post-burn from burned plots to perform physicochemical and metabarcode DNA analyses.Results:Prescribed burning had no significant effect on the total fungal operational taxonomic unit richness and abundance.However,changes in soil pH,nitrogen and potassium content post-burn affected fungal community composition.Small non-significant changes in pH and phosphorous affected the composition of ectomycorrhizal fungi.Conclusions:The ectomycorrhizal fungal community appears to be resilient to the effects of low-to moderate-intensity fires and saprotrophic taxa may benefit from this kind of fire.This finding revealed that prescribed burning is a potentially valuable management tool for reducing fire hazards in shrublands that has little effect on the total richness and abundance of fungal communities. 展开更多
关键词 Doñana National Park Ectomycorrhizal fungi Fire ecology Forest management Global change Prescribed burning WILDFIRE Saprotrophic fungi
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Intelligent Deep Learning Enabled Wild Forest Fire Detection System
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作者 Ahmed S.Almasoud 《Computer Systems Science & Engineering》 SCIE EI 2023年第2期1485-1498,共14页
The latest advancements in computer vision and deep learning(DL)techniques pave the way to design novel tools for the detection and monitoring of forestfires.In this view,this paper presents an intelligent wild forestfi... The latest advancements in computer vision and deep learning(DL)techniques pave the way to design novel tools for the detection and monitoring of forestfires.In this view,this paper presents an intelligent wild forestfire detec-tion and alarming system using deep learning(IWFFDA-DL)model.The pro-posed IWFFDA-DL technique aims to identify forestfires at earlier stages through integrated sensors.The proposed IWFFDA-DL system includes an Inte-grated sensor system(ISS)combining an array of sensors that acts as the major input source that helps to forecast thefire.Then,the attention based convolution neural network with bidirectional long short term memory(ACNN-BLSTM)model is applied to examine and identify the existence of danger.For hyperpara-meter tuning of the ACNN-BLSTM model,the bacterial foraging optimization(BFO)algorithm is employed and thereby enhances the detection performance.Finally,when thefire is detected,the Global System for Mobiles(GSM)modem transmits messages to the authorities to take required actions.An extensive set of simulations were performed and the results are investigated interms of several aspects.The obtained results highlight the betterment of the IWFFDA-DL techni-que interms of various measures. 展开更多
关键词 Forestfire deep learning intelligent models metaheuristics integrated sensor system hyperparameter tuning
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Deep learning for predictive mechanical properties of hot-rolled strip in complex manufacturing systems
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作者 Feifei Li Anrui He +5 位作者 Yong Song Zheng Wang Xiaoqing Xu Shiwei Zhang Yi Qiang Chao Liu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2023年第6期1093-1103,共11页
Higher requirements for the accuracy of relevant models are put throughout the transformation and upgrade of the iron and steel sector to intelligent production.It has been difficult to meet the needs of the field wit... Higher requirements for the accuracy of relevant models are put throughout the transformation and upgrade of the iron and steel sector to intelligent production.It has been difficult to meet the needs of the field with the usual prediction model of mechanical properties of hotrolled strip.Insufficient data and difficult parameter adjustment limit deep learning models based on multi-layer networks in practical applications;besides,the limited discrete process parameters used make it impossible to effectively depict the actual strip processing process.In order to solve these problems,this research proposed a new sampling approach for mechanical characteristics input data of hot-rolled strip based on the multi-grained cascade forest(gcForest)framework.According to the characteristics of complex process flow and abnormal sensitivity of process path and parameters to product quality in the hot-rolled strip production,a three-dimensional continuous time series process data sampling method based on time-temperature-deformation was designed.The basic information of strip steel(chemical composition and typical process parameters)is fused with the local process information collected by multi-grained scanning,so that the next link’s input has both local and global features.Furthermore,in the multi-grained scanning structure,a sub sampling scheme with a variable window was designed,so that input data with different dimensions can get output characteristics of the same dimension after passing through the multi-grained scanning structure,allowing the cascade forest structure to be trained normally.Finally,actual production data of three steel grades was used to conduct the experimental evaluation.The results revealed that the gcForest-based mechanical property prediction model outperforms the competition in terms of comprehensive performance,ease of parameter adjustment,and ability to sustain high prediction accuracy with fewer samples. 展开更多
关键词 hot-rolled strip prediction of mechanical properties deep learning multi-grained cascade forest time series feature extraction variable window subsampling
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Novel Computer-Aided Diagnosis System for the Early Detection of Alzheimer’s Disease
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作者 Meshal Alharbi Shabana R.Ziyad 《Computers, Materials & Continua》 SCIE EI 2023年第3期5483-5505,共23页
Aging is a natural process that leads to debility,disease,and dependency.Alzheimer’s disease(AD)causes degeneration of the brain cells leading to cognitive decline and memory loss,as well as dependence on others to f... Aging is a natural process that leads to debility,disease,and dependency.Alzheimer’s disease(AD)causes degeneration of the brain cells leading to cognitive decline and memory loss,as well as dependence on others to fulfill basic daily needs.AD is the major cause of dementia.Computer-aided diagnosis(CADx)tools aid medical practitioners in accurately identifying diseases such as AD in patients.This study aimed to develop a CADx tool for the early detection of AD using the Intelligent Water Drop(IWD)algorithm and the Random Forest(RF)classifier.The IWD algorithm an efficient feature selection method,was used to identify the most deterministic features of AD in the dataset.RF is an ensemble method that leverages multiple weak learners to classify a patient’s disease as either demented(DN)or cognitively normal(CN).The proposed tool also classifies patients as mild cognitive impairment(MCI)or CN.The dataset on which the performance of the proposed CADx was evaluated was sourced from the Alzheimer’s Disease Neuroimaging Initiative(ADNI).The RF ensemble method achieves 100%accuracy in identifying DN patients from CN patients.The classification accuracy for classifying patients as MCI or CN is 92%.This study emphasizes the significance of pre-processing prior to classification to improve the classification results of the proposed CADx tool. 展开更多
关键词 Alzheimer’s disease DEMENTIA mild cognitive impairment computer-aided diagnosis intelligent water drop algorithm random forest
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Intelligent Sound-Based Early Fault Detection System for Vehicles
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作者 Fawad Nasim Sohail Masood +2 位作者 Arfan Jaffar Usman Ahmad Muhammad Rashid 《Computer Systems Science & Engineering》 SCIE EI 2023年第9期3175-3190,共16页
An intelligent sound-based early fault detection system has been proposed for vehicles using machine learning.The system is designed to detect faults in vehicles at an early stage by analyzing the sound emitted by the... An intelligent sound-based early fault detection system has been proposed for vehicles using machine learning.The system is designed to detect faults in vehicles at an early stage by analyzing the sound emitted by the car.Early detection and correction of defects can improve the efficiency and life of the engine and other mechanical parts.The system uses a microphone to capture the sound emitted by the vehicle and a machine-learning algorithm to analyze the sound and detect faults.A possible fault is determined in the vehicle based on this processed sound.Binary classification is done at the first stage to differentiate between faulty and healthy cars.We collected noisy and normal sound samples of the car engine under normal and different abnormal conditions from multiple workshops and verified the data from experts.We used the time domain,frequency domain,and time-frequency domain features to detect the normal and abnormal conditions of the vehicle correctly.We used abnormal car data to classify it into fifteen other classical vehicle problems.We experimented with various signal processing techniques and presented the comparison results.In the detection and further problem classification,random forest showed the highest results of 97%and 92%with time-frequency features. 展开更多
关键词 Sound classification signal processing random forest random tree time-frequency domain J48
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The Anzhen Risk Scoring System for Acute Type A Aortic Dissection:A Prospective Observational Study Protocol
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作者 Bo Jia Cheng Luo +6 位作者 Chengnan Li Yipeng Ge Yongliang Zhong Zhiyu Qiao Haiou Hu Suwei Chen Junming Zhu 《Cardiovascular Innovations and Applications》 2023年第1期25-31,共7页
Introduction:Acute type A aortic dissection(ATAAD)is a catastrophic disease with fatal outcomes.Malperfusion syndrome(MPS)is a serious complication of ATAAD,with an incidence of 20–40%.Many studies have shown that MP... Introduction:Acute type A aortic dissection(ATAAD)is a catastrophic disease with fatal outcomes.Malperfusion syndrome(MPS)is a serious complication of ATAAD,with an incidence of 20–40%.Many studies have shown that MPS is the main risk factor for poor ATAAD prognosis.However,a risk scoring system for ATAAD based on MPS is lacking.Here,we designed a risk scoring system for ATAAD to assess mortality through quantitative assessment of relevant organ malperfusion and subsequently develop rational treatment strategies.Methods and analysis:This was a prospective observational study.Patients’perioperative clinical data were col-lected to establish a database of ATAAD(N≥3000)and determine whether these patients had malperfusion complica-tions.The Anzhen risk scoring system was established on the basis of organ malperfusion by using a random forest survival model and a logistics model.The better method was then chosen to establish a revised risk scoring system.Ethics and dissemination:This study received ethical approval from the Ethics Committees of Beijing Anzhen Hospital,Capital Medical University(KS2019034-1).Patient consent was waived because biological samples were not collected,and no patient rights were violated.Findings will be disseminated at scientific conferences and in peer-reviewed publications. 展开更多
关键词 Acute type A Aortic Dissection 30-Day mortality Risk prediction Random Forest survival Malperfu-sion syndrome
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An Intrusion Detection System for SDN Using Machine Learning
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作者 G.Logeswari S.Bose T.Anitha 《Intelligent Automation & Soft Computing》 SCIE 2023年第1期867-880,共14页
Software Defined Networking(SDN)has emerged as a promising and exciting option for the future growth of the internet.SDN has increased the flexibility and transparency of the managed,centralized,and controlled network... Software Defined Networking(SDN)has emerged as a promising and exciting option for the future growth of the internet.SDN has increased the flexibility and transparency of the managed,centralized,and controlled network.On the other hand,these advantages create a more vulnerable environment with substantial risks,culminating in network difficulties,system paralysis,online banking frauds,and robberies.These issues have a significant detrimental impact on organizations,enterprises,and even economies.Accuracy,high performance,and real-time systems are necessary to achieve this goal.Using a SDN to extend intelligent machine learning methodologies in an Intrusion Detection System(IDS)has stimulated the interest of numerous research investigators over the last decade.In this paper,a novel HFS-LGBM IDS is proposed for SDN.First,the Hybrid Feature Selection algorithm consisting of two phases is applied to reduce the data dimension and to obtain an optimal feature subset.In thefirst phase,the Correlation based Feature Selection(CFS)algorithm is used to obtain the feature subset.The optimal feature set is obtained by applying the Random Forest Recursive Feature Elimination(RF-RFE)in the second phase.A LightGBM algorithm is then used to detect and classify different types of attacks.The experimental results based on NSL-KDD dataset show that the proposed system produces outstanding results compared to the existing methods in terms of accuracy,precision,recall and f-measure. 展开更多
关键词 Intrusion detection system light gradient boosting machine correlation based feature selection random forest recursive feature elimination software defined networks
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Ecosystem Service Value Assessment of Wutong Mountain Rhododendron moulmainense Ecological Landscape Forest in Shenzhen City in 2021
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作者 Rui CONG Kaiwen ZHANG +1 位作者 Xiaodan CHEN Dingyue WANG 《Agricultural Biotechnology》 CAS 2023年第4期88-92,共5页
Taking Wutong Mountain Rhododendron moulmainense ecological landscape forest in Shenzhen City as an example,the value of the forest was assessed by constructing an ecological service value assessment system and accoun... Taking Wutong Mountain Rhododendron moulmainense ecological landscape forest in Shenzhen City as an example,the value of the forest was assessed by constructing an ecological service value assessment system and accounting method.The assessment results showed that the total ecosystem service value of R.moulmainense ecological landscape forest was 13.195 billion yuan,and the top three services included the value of forestry products,the value of biodiversity maintenance and the value of leisure and recreation,indicating that the ecosystem service of Wutong Mountain R.moulmainense ecological landscape forest in Shenzhen has great ecological and economic value,especially in forestry products,biodiversity maintenance,and leisure and recreation. 展开更多
关键词 Wutong Mountain Rhododendron moulmainense Ecological landscape forest Ecosystem services Value assessment
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