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东西伯利亚地区植被对气温和降水交互作用的定量化响应

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Journal of geographical Sciences 2024年第2期34卷 355-374页

作者：文可戈李程何剑锋庄大方 State Key Laboratory of Resources and Environment information system Institute of Geographic Sciencesand Natural Resources ResearchCASBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Nanjing Agricultural University Nanjing 210095China

Significant changes to the world’s climate over the past few decades have had an impact on the development of *** in high latitude regions,where the ecosystems are fragile,is susceptible to climate *** is possible to better understand vegetation’s phenological response to climate change by examining these *** studies have mainly investigated how a single meteorological factor affects changes in vegetation phenology through linear correlation analysis,which is insufficient for quantitatively revealing the effects of various climate factor interactions on changes in vegetation *** used the asymmetric Gaussian method to fit the normalized difference vegetation index(NDVI)curve and then used the dynamic threshold method to extract the phenological parameters,including the start of the season(SOS),end of the season(EOS),and length of the season(LOS),of the vegetation in this study area in the Tundra-Tagar transitional zone in eastern and western Siberia from 2000 to *** monthly temperature and precipitation data used in this study were obtained from the climate research unit(CRU)meteorological *** degrees to which the changes in temperature and precipitation in the various months and their interactions affected the changes in the three phenological parameters were determined using the GeoDetector,and the results were *** findings demonstrate that the EOS was more susceptible to climate change than the *** vegetation phenology shift was best explained by the climate in March,April,and September,and the combined effect of the temperature and precipitation had a greater impact on the change in the vegetation phenology compared with the effects of the individual climate *** results quantitatively show the degree of interaction between the variations in temperature and precipitation and their effects on the changes in the different phenological parameters in the various *** how

关键词： phenology climate change Siberia asymmetric Gaussian function GeoDetector

An Implementation of Multiscale Line Detection and Mathematical Morphology for Efficient and Precise Blood Vessel Segmentation in Fundus Images

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Computers, Materials & Continua 2024年第5期79卷 2565-2583页

作者： Syed Ayaz Ali Shah Aamir Shahzad Musaed Alhussein Chuan Meng Goh Khursheed Aurangzeb Tong Boon Tang Muhammad Awais Department of Electrical and Computer Engineering COMSATS University IslamabadAbbottabad CampusAbbottabad22060Pakistan Department of Computer Engineering College of Computer and Information SciencesKing Saud UniversityP.O.Box 51178Riyadh11543Saudi Arabia Faculty of information and Communication Technology University Tunku Abdul RehmanKampar CampusKampar31900Malaysia centre for Intelligent Signal and Imaging Research University Teknologi PETRONASBandar Seri IskandarPerak32610Malaysia School of Computing Sciences University of East AngliaNorwichNR47TJUK

Diagnosing various diseases such as glaucoma,age-related macular degeneration,cardiovascular conditions,and diabetic retinopathy involves segmenting retinal blood *** task is particularly challenging when dealing with color fundus images due to issues like non-uniformillumination,low contrast,and variations in vessel appearance,especially in the presence of different ***,the speed of the retinal vessel segmentation system is of utmost *** the surge of now available big data,the speed of the algorithm becomes increasingly important,carrying almost equivalent weightage to the accuracy of the *** address these challenges,we present a novel approach for retinal vessel segmentation,leveraging efficient and robust techniques based on multiscale line detection and mathematical *** algorithm’s performance is evaluated on two publicly available datasets,namely the Digital Retinal Images for Vessel Extraction dataset(DRIVE)and the Structure Analysis of Retina(STARE)*** experimental results demonstrate the effectiveness of our method,withmean accuracy values of 0.9467 forDRIVE and 0.9535 for STARE datasets,aswell as sensitivity values of 0.6952 forDRIVE and 0.6809 for STARE ***,our algorithmexhibits competitive performance with state-of-the-art ***,it operates at an average speed of 3.73 s per image for DRIVE and 3.75 s for STARE *** is worth noting that these results were achieved using Matlab scripts containing multiple *** suggests that the processing time can be further reduced by replacing loops with *** the proposed algorithm can be deployed in real time *** summary,our proposed system strikes a fine balance between swift computation and accuracy that is on par with the best available methods in the field.

关键词： Line detector vessel detection localization mathematical morphology image processing

The oasis expansion and eco-environment change over the last 50 years in Manas River Valley, Xinjiang

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Science China Earth Sciences 2006年第2期49卷 163-175页

作者： CHENG Weiming ZHOU Chenghu LIU Haijiang ZHANG Yang JIANG Yan ZHANG Yichi YAO Yonghui State Key Laboratory of Resource and Environmental information system Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China State Key Laboratory of Resource and Environmental Information System Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China State Key Laboratory of Resource and Environmental Information System Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China State Key Laboratory of Resource and Environmental Information System Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China State Key Laboratory of Resource and Environmental Information System Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China State Key Laboratory of Resource and Environmental Information System Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China State Key Laboratory of Resource and Environmental Information System Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China

The oasis expansion and economic development of the Manas River Valley is one of the most successful examples in Xinjiang. In this paper, the oasis spatial distribution pattern and dynamic change were examined using imageries of Landsat MSS, TM and ETM, land use and topographic maps in six different periods (such as 1949, 1962, 1976, 1989, 1999 and 2001) over the last 50 years in the valley. The oasis expansion process could be divided into two stages according to the annual rate of oasis area increase, the fast oasization stage (from 1949 to 1976) when the oasis area ex-panded from 156.385 km2 in 1949 to 3,639.491 km2 in 1976 because of rapidly increased population and quickly enlarged farmland area; and the urbanization stage (from 1976 to 2001) when the ex-pansion ratio of farmland slowed down, and the urbanization process quickened, the total oasis area reached 5042.440 km2 in 2001. With the continuous expansion of oasis and farmland, a large quantity of river water was drawn into irrigation ditch and plain lakes, so only a small quantity of river water could flow into lakes, as a result, the Manas Lake dried up, salization and basification problems happened in the low-lying oasis region. The natural swamp around the lake was shrunk greatly and biodiversity decreased significantly. The driving force analysis reveals that human activities, such as reclamation and population growth, played a major role in the oasis expansion and ecological dete-rioration in the Manas River Valley. So further efforts should be made to improve the efficiency of water resource utility and adjust layout of the regional agricultural and animal husbandry to keep the sustainable development of oasis economic belt of the northern slope of Tianshan Mts.

关键词： Manas River Valley, oasization, urbanization, salinization and basification, remote sensing (RS).

Drivers,Trends,and Patterns of Changing Vegetation-greenness in Nansha Islands,China from 2016 to 2022

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Chinese geographical Science 2024年第4期34卷 662-673页

作者： TANG Jiasheng FU Dongjie SU Fenzhen YU Hao WANG Xinhui Faculty of Geomatics Lanzhou Jiaotong UniversityLanzhou 730070China State Key Laboratory of Resources and Environmental information system Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China Collaborative Innovation Center of South China Sea Studies Nanjing 210023China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100049China Beijing North-Star Technology Development Co. LtdBeijing 100120China

Changes in vegetation status generally also represents changes in the ecological health of islands and reefs(IRs).However,studies are limited of drivers and trends of vegetation change of Nansha Islands,China and how they relate to climate change and human *** resolve this limitation,we studied changes to the Normalized Difference Vegetation Index(NDVI)vegetation-greenness index for 22 IRs of Nansha Islands during normal and extreme *** of vegetation greenness were analyzed using Sen's slope and Mann-Kendall test at two spatial scales(pixel and island),and driving factor analyses were performed by time-lagged partial correlation *** were related to impacts from human activities and climatic factors under normal(temperature,precipitation,radiation,and Normalized Difference Built-up Index(NDBI))and extreme conditions(wind speed and latitude of IRs)from 2016 to *** showed:1)among the 22 IRs,NDVI increased/decreased significantly in 15/4 IRs,*** Reef had the highest NDVI change-rate(0.48%/mon),and Zhongye Island had the lowest(–0.29%/mon).Local spatial patterns were in one of two forms:dotted-form,and degradation in banded-form.2)Under normal conditions,human activities(characterized by NDBI)had higher impacts on vegetation-greenness than other factors.3)Under extreme conditions,wind speed(R^(2)=0.2337,P<0.05)and latitude(R^(2)=0.2769,P<0.05)provided limited explanation for changes from typhoon *** results provide scientific support for the sustainable development of Nansha Islands and the United Nations‘Ocean Decade’initiative.

关键词： island and reefs(IRs) Normalized Difference Vegetation Index(NDVI) vegetation-greenness change-rate Sen's slope Nansha Islands China

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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Computer Modeling in Engineering & Sciences 2024年第3期138卷 2873-2897页

作者： Yingui Qiu Shuai Huang Danial Jahed Armaghani Biswajeet Pradhan Annan Zhou Jian Zhou School of Resources and Safety Engineering Central South UniversityChangsha410083China School of Civil and Environmental Engineering University of Technology SydneyNew South WalesAustralia centre for Advanced Modelling and Geospatial information systems School of Civil and Environmental EngineeringFaculty of Engineering and Information TechnologyUniversity of Technology SydneyNew SouthWalesAustralia Civil and Infrastructure Engineering Discipline School of EngineeringRoyal Melbourne Institute of Technology(RMIT)MelbourneVictoria3001Australia

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 *** the other hand,a reliable and accurate prediction of TBM performance is essential to planning an applicable tunnel construction *** performance of TBM is very difficult to estimate due to various geotechnical and geological factors and machine *** previously-proposed intelligent techniques in this field are mostly based on a single or base model with a low level of ***,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 *** the modelling of this study,a comprehensive databasewith themost influential parameters onTBMtogetherwithTBM AR were used as input and output variables,*** 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 *** 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 *** newly-developedGOGHS-RFmodel enjoyed R2=0.9937 and 0.9844,respectively,for train and test stages,which are higher than a pre-developed ***,the importance of the input parameters was interpreted through the SHapley Additive exPlanations(SHA

关键词： Tunnel boring machine random forest GOGHS optimization PSO optimization GA optimization ABC optimization SHAP

Road Centrality and Landscape Spatial Patterns in Wuhan Metropolitan Area,China

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Chinese geographical Science 2015年第4期25卷 511-522页

作者： LIU Yaolin WANG Huimin JIAO Limin LIU Yanfang HE Jianhua AI Tinghua School of Resource and Environment Science Wuhan University Key Laboratory of geographical information system Ministry of Education Wuhan University

Road network is a corridor system that interacts with surrounding landscapes,and understanding their interaction helps to develop an optimal plan for sustainable transportation and land *** study investigates the relationships between road centrality and landscape patterns in the Wuhan Metropolitan Area,*** densities of centrality measures,including closeness,betweenness,and straightness,are calculated by kernel density estimation(KDE).The landscape patterns are characterized by four landscape metrics,including percentage of landscape(PLAND),Shannon′s diversity index(SHDI),mean patch size(MPS),and mean shape index(MSI).Spearman rank correlation analysis is then used to quantify their relationships at both landscape and class *** results show that the centrality measures can reflect the hierarchy of road network as they associate with road *** analysis exhibit that as centrality densities increase,the whole landscape becomes more fragmented and *** the class level,the forest gradually decreases and becomes fragmented,while the construction land increases and turns to more ***,these findings indicate that the ability and potential applications of centrality densities estimated by KDE in quantifying the relationships between roads and landscapes,can provide detailed information and valuable guidance for transportation and land-use planning as well as a new insight into ecological effects of roads.

关键词： road centrality landscape patterns kernel density estimation(KDE) landscape metrics Wuhan Metropolitan Area China

Urban Sprawl and Related Problems: Bibliometric Analysis and Refined Analysis from 1991 to 2011

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Chinese geographical Science 2014年第2期24卷 245-257页

作者： ZENG Chen LIU Yaolin LIU Yanfang QIU Liquan School of Resource and Environment Science Wuhan University Key Laboratory of geographical information system Ministry of EducationWuhan University

To shed light on the general patterns and trends in urban sprawl research,and to provide reference for future study,bibliometric analysis and refined analysis are conducted for publications in this area from 1991 to *** general publication output,the global geographical distribution of the authors,the funding and institutions involved,the research areas,and the source titles are analyzed and *** in the United States and China have produced most of the documents in urban sprawl and these two countries are also the largest contributors in terms of funding and institutions.′Environmental Sciences&Ecology′,′Urban Studies′,and′Geography′are the most common research areas,and the journal titled Urban Studies has contributed the most ***,the refined analyses on the 500 top-cited and most relevant publications have revealed that research on urban sprawl is closely associated with the categories of′Urban form and development′,′Land use/land development′and′environment/ecology/biology′.Conclusions are made with respect to the basic paradigm of research on urban *** multi-disciplinary research into urban sprawl are expected to be more diversified and integrated.

关键词： urban sprawl bibliometrics scientific output multi-discipline

On 3D simulation of moving objects in a digital earth system

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Science China(Technological Sciences) 2008年第S2期51卷 123-132页

作者： WENG JingNong1,WU Lun2,HUANG Jian1,WANG Yang1,YANG Xue1 & HU Bin1 1 College of Software,Beihang University,Beijing 100191,China 2 Institute of geographical information system and Remote Sensing,Peking University,Beijing 100871,China College of Software Beihang University Beijing China Institute of geographical information system and Remote Sensing Peking University Beijing China

"How do the rescue helicopters find out an optimized path to arrive at the site of a disaster as soon as possible?" or "How are the flight procedures over mountains and plateaus simulated?" and so *** this paper a script language on spatial moving objects is presented by abstracting 3D spatial moving objects' behavior when implementing moving objects simulation in 3D digital Earth scene,which is based on a platform of digital China named "ChinaStar".The definition of this script language,its morphology and syntax,its compiling and mediate language generating,and the behavior and state control of spatial moving objects are discussed *** addition,the language's applications and implementation are also discussed.

关键词： Digital Earth ChinaStar moving object script language

Parameterization, sensitivity, and uncertainty of 1-D thermodynamic thin-ice thickness retrieval

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Acta Oceanologica Sinica 2024年第7期43卷 93-111页

作者： Tianyu Zhang Mohammed Shokr Zhida Zhang Fengming Hui Xiao Cheng Zhilun Zhang Jiechen Zhao Chunlei Mi School of Geospatial Engineering and Science Sun Yat-Sen University/Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)Zhuhai 519082China Key Laboratory of Comprehensive Observation of Polar Environment(Sun Yat-Sen University) Ministry of EducationZhuhai 519082China State Key Laboratory of Remote Sensing Science College of Global Change and Earth System ScienceBeijing Normal UniversityBeijing 100875China Science and Technology Branch Environment and Climate Change CanadaToronto M3H5T4Canada Qingdao Innovation and Development Base(centre) Harbin Engineering UniversityQingdao 266500China State Key Laboratory of Resources and Environmental information system Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China

Retrieval of Thin-Ice Thickness(TIT)using thermodynamic modeling is sensitive to the parameterization of the independent variables(coded in the model)and the uncertainty of the measured input *** article examines the deviation of the classical model’s TIT output when using different parameterization schemes and the sensitivity of the output to the ice ***,it estimates the uncertainty of the output in response to the uncertainties of the input *** parameterized independent variables include atmospheric longwave emissivity,air density,specific heat of air,latent heat of ice,conductivity of ice,snow depth,and snow *** input parameters include air temperature,ice surface temperature,and wind *** the independent variables,the results show that the highest deviation is caused by adjusting the parameterization of snow conductivity and depth,followed ice *** sensitivity of the output TIT to ice thickness is highest when using parameterization of ice conductivity,atmospheric emissivity,and snow conductivity and *** retrieved TIT obtained using each parameterization scheme is validated using in situ measurements and satellite-retrieved *** in situ measurements,the uncertainties of the measured air temperature and surface temperature are found to be *** resulting uncertainties of TIT are evaluated using perturbations of the input data selected based on the probability distribution of the measurement *** results show that the overall uncertainty of TIT to air temperature,surface temperature,and wind speed uncertainty is around 0.09 m,0.049 m,and−0.005 m,respectively.

关键词： Arctic sea ice 1-D thermodynamic ice model thin-ice thickness sea ice parameterization