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Mapping ecosystem services in urban and peri-urban areas.A systematic review
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作者 Paulo Pereira Miguel Inácio +3 位作者 Luis Pinto Marius Kalinauskas Katarzyna Bogdzevic Wenwu Zhao 《Geography and Sustainability》 CSCD 2024年第3期491-509,共19页
Urban and peri-urban ecosystems are subjected to an intense impact.The demand for ecosystem services(ES)is higher in these areas.Nevertheless,despite the anthropogenic pressures,urban and peri-urban ecosystems supply ... Urban and peri-urban ecosystems are subjected to an intense impact.The demand for ecosystem services(ES)is higher in these areas.Nevertheless,despite the anthropogenic pressures,urban and peri-urban ecosystems supply important ES.Mapping is a crucial exercise to understand ES dynamics in these environments better.This work aims to systematically review mapping ES in urban and peri-urban areas studies,following the Preferred Reporting Items for Systematic Reviews and Meta-alpha Methods.A total of 207 studies were selected.The results show increased work between 2011 and 2023,mainly conducted in Europe and China.Most work were developed in urban areas and did not follow an established ES classification.Most studies focused on the ES supply dimension,the regulation and maintenance section.Regarding provisioning ES,most studies focused on Cultivating terrestrial plants for nutrition,regulating and maintainin g Atmospheric composition and conditions,and for cultural ES on Physical and experiential interactions with the natural environment.Quantitative methods were mostly applied following Indicator-based(secondary data:biophysical,socio-economic)models.Very few work validated the outputs.Several studies forecasted ES,primarily based on land use changes using CA-Markov approaches.This study provides an overview of the most mapped urban and peri-urban ES globally,the areas where more studies need to be conducted,and the methods developed. 展开更多
关键词 Systematic review Urban and peri-urban areas Ecosystem services mapping METHODS
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Uncertainties of landslide susceptibility prediction:influences of different study area scales and mapping unit scales
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作者 Faming Huang Yu Cao +4 位作者 Wenbin Li Filippo Catani Guquan Song Jinsong Huang Changshi Yu 《International Journal of Coal Science & Technology》 EI CAS CSCD 2024年第2期143-172,共30页
This study aims to investigate the effects of different mapping unit scales and study area scales on the uncertainty rules of landslide susceptibility prediction(LSP).To illustrate various study area scales,Ganzhou Ci... This study aims to investigate the effects of different mapping unit scales and study area scales on the uncertainty rules of landslide susceptibility prediction(LSP).To illustrate various study area scales,Ganzhou City in China,its eastern region(Ganzhou East),and Ruijin County in Ganzhou East were chosen.Different mapping unit scales are represented by grid units with spatial resolution of 30 and 60 m,as well as slope units that were extracted by multi-scale segmentation method.The 3855 landslide locations and 21 typical environmental factors in Ganzhou City are first determined to create spatial datasets with input-outputs.Then,landslide susceptibility maps(LSMs)of Ganzhou City,Ganzhou East and Ruijin County are pro-duced using a support vector machine(SVM)and random forest(RF),respectively.The LSMs of the above three regions are then extracted by mask from the LSM of Ganzhou City,along with the LSMs of Ruijin County from Ganzhou East.Additionally,LSMs of Ruijin at various mapping unit scales are generated in accordance.Accuracy and landslide suscepti-bility indexes(LSIs)distribution are used to express LSP uncertainties.The LSP uncertainties under grid units significantly decrease as study area scales decrease from Ganzhou City,Ganzhou East to Ruijin County,whereas those under slope units are less affected by study area scales.Of course,attentions should also be paid to the broader representativeness of large study areas.The LSP accuracy of slope units increases by about 6%–10%compared with those under grid units with 30 m and 60 m resolution in the same study area's scale.The significance of environmental factors exhibits an averaging trend as study area scale increases from small to large.The importance of environmental factors varies greatly with the 60 m grid unit,but it tends to be consistent to some extent in the 30 m grid unit and the slope unit. 展开更多
关键词 Landslide susceptibility prediction Uncertainty analysis Study areas scales mapping unit scales Slope units Random forest
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健康人膝关节股骨内侧髁软骨的T_(2) mapping研究
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作者 曹娜娜 王莉 +3 位作者 万业达 郭林 胡鹏 何岸苇 《国际医学放射学杂志》 2024年第2期185-189,共5页
目的应用T_(2) mapping技术测量健康人膝关节股骨内侧髁负重区与非负重区各层软骨T_(2)值并分析其差异,探讨膝关节软骨分层、分区域MRI定量研究的价值。方法前瞻性纳入22名健康志愿者,其中男、女各11名,平均年龄(27.05±1.05)岁。... 目的应用T_(2) mapping技术测量健康人膝关节股骨内侧髁负重区与非负重区各层软骨T_(2)值并分析其差异,探讨膝关节软骨分层、分区域MRI定量研究的价值。方法前瞻性纳入22名健康志愿者,其中男、女各11名,平均年龄(27.05±1.05)岁。共纳入38个膝关节,左膝20个,右膝18个。对志愿者行膝关节MRI矢状面T_(2) mapping检查,选取膝关节股骨内侧髁负重区35个、非负重区37个,并测量完整关节软骨上最厚处的T_(2)值。采用独立样本t检验和方差分析分别比较股骨内侧髁负重区与非负重区各层软骨的T_(2)值及各区域内关节软骨浅、中、深层的T_(2)值。结果股骨内侧髁负重区及非负重区的软骨各层T_(2)值由大到小依次为浅层、中层、深层,除非负重区软骨浅层与中层间的T_(2)值差异无统计学意义(P>0.05),余各2层间T_(2)值差异均有统计学意义(均P<0.05);负重区软骨中层、深层T_(2)值均小于非负重区(均P<0.05),负重区与非负重区软骨浅层的T_(2)值差异无统计学意义(P>0.05)。结论健康人膝关节软骨依据T_(2)值差异可分为3层且负重区软骨T_(2)值更低,对膝关节软骨分层、分区域研究具有可行性。 展开更多
关键词 膝关节软骨 磁共振成像 T_(2)mapping 负重区 分层
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Digital Geological Mapping of Sinus Iridum Area of the Moon Based on the Chang'E-I Data 被引量:3
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作者 DING Xiaozhong HAN Kunying +4 位作者 PANG Jianfeng WANG Liang HAN Tonglin JU Yuanjing DING Weicui 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2013年第6期1643-1657,共15页
Based on the CCD images,IIM data and DEM data of China's lunar exploration project (Chang'E-Ⅰ) and related processed and analytic results,an integrated study of regional geology of Sinus Iridum and its adjacent a... Based on the CCD images,IIM data and DEM data of China's lunar exploration project (Chang'E-Ⅰ) and related processed and analytic results,an integrated study of regional geology of Sinus Iridum and its adjacent area was conducted,and a series of relevant researches and analyses were carried out,including analysis of impact craters and their extrusive and accumulative materials,division of stratigraphic and tectonic units and classification of rock types,integrated analysis of chronology and lunar evolution history.In consideration of crater's shape features,quantity and preserving status of filling materials,the lunar impact craters can be divided into 7 types and 11 subtypes,and the accumulative materials of craters are divided into 6 types and 9 accumulative groups.According to the content and distribution of TiO2 and image characteristics,the basalts are divided into high-TiO2,medium-TiO2 and low-TiO2 basalts.Discussion was made on division of tectonic units and evolution features in the study area.The geological map of the Sinus Iridum Quadrangle (LQ-4) at a scale of 1∶2.5 M was preliminarily compiled with the ArcGIS system,and the spatial database of the map was established.Related technical specification,procedure and method for lunar geological mapping have been worked out,so as to lay a foundation for the forthcoming geological mapping of the global Moon in China by using the data of Chang'E-Ⅱ and also for comprehensive study and geological mapping of other celestial bodies in the future. 展开更多
关键词 The Moon Sinus Iridum area Chang'E-Ⅰ geological mapping geological map database
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Mapping of moraine dammed glacial lakes and assessment of their areal changes in the central and eastern Himalayas using satellite data 被引量:3
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作者 Sazeda BEGAM Dhrubajyoti SEN 《Journal of Mountain Science》 SCIE CSCD 2019年第1期77-94,共18页
The relatively rapid recession of glaciers in the Himalayas and formation of moraine dammed glacial lakes(MDGLs) in the recent past have increased the risk of glacier lake outburst floods(GLOF) in the countries of Nep... The relatively rapid recession of glaciers in the Himalayas and formation of moraine dammed glacial lakes(MDGLs) in the recent past have increased the risk of glacier lake outburst floods(GLOF) in the countries of Nepal and Bhutan and in the mountainous territory of Sikkim in India. As a product of climate change and global warming, such a risk has not only raised the level of threats to the habitation and infrastructure of the region, but has also contributed to the worsening of the balance of the unique ecosystem that exists in this domain that sustains several of the highest mountain peaks of the world. This study attempts to present an up to date mapping of the MDGLs in the central and eastern Himalayan regions using remote sensing data, with an objective to analyse their surface area variations with time from 1990 through 2015, disaggregated over six episodes. The study also includes the evaluation for susceptibility of MDGLs to GLOF with the least criteria decision analysis(LCDA). Forty two major MDGLs, each having a lake surface area greater than 0.2 km2, that were identified in the Himalayan ranges of Nepal, Bhutan, and Sikkim, have been categorized according to their surface area expansion rates in space and time. The lakes have been identified as located within the elevation range of 3800 m and6800 m above mean sea level(a msl). With a total surface area of 37.9 km2, these MDGLs as a whole were observed to have expanded by an astonishing 43.6% in area over the 25 year period of this study. A factor is introduced to numerically sort the lakes in terms of their relative yearly expansion rates, based on their interpretation of their surface area extents from satellite imageries. Verification of predicted GLOF events in the past using this factor with the limited field data as reported in literature indicates that the present analysis may be considered a sufficiently reliable and rapid technique for assessing the potential bursting susceptibility of the MDGLs. The analysis also indicates that, as of now, there are eight MDGLs in the region which appear to be in highly vulnerable states and have high chances in causing potential GLOF events anytime in the recent future. 展开更多
关键词 GLACIER RETREAT LAKES mapping MORAINE dammed GLACIAL lake(MDGL) Surface area change of LAKES Landsat imagery data Least criteria decision analysis(LCDA)
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A MODIS Time Series Data Based Algorithm for Mapping Forest Fire Burned Area 被引量:4
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作者 YANG Wei ZHANG Shuwen +3 位作者 TANG Junmei BU Kun YANG Jiuchun CHANG Liping 《Chinese Geographical Science》 SCIE CSCD 2013年第3期344-352,共9页
Burned area mapping is an essential step in the forest fire research to investigate the relationship between forest fire and cli- mate change and the effect of forest fire on carbon budgets. This study proposed an alg... Burned area mapping is an essential step in the forest fire research to investigate the relationship between forest fire and cli- mate change and the effect of forest fire on carbon budgets. This study proposed an algorithm to map forest fire burned area using the Moderate-Resolution Imaging Spectroradiameter (MODIS) time series data in Heilongjiang Province, China. The algorithm is divided into two steps: Firstly, the 'core' pixels were extracted to represent the most possible burned pixels based on the comparison of the tem- poral change of Global Environmental Monitoring Index (GEMI), Burned Area Index (BAI) and MODIS active fire products between pre- and post-fires. Secondly, a 15-km distance was set to extract the entire burned areas near the 'core' pixels as more relaxed conditions were used to identify the fire pixels for reducing the omission error as much as possible. The algorithm comprehensively considered the thermal characteristics and the spectral change between pre- and post-fires, which are represented by the MODIS fire products and the spectral index, respectively. Tahe, Mohe and Huma counties of Heilongjiang Province, China were chosen as the study area for burned area mapping and a time series of burned maps were produced from 2000 to 2011. The results show that the algorithm can extract burned areas more accurately with the hiehest accuracy of 96.61%. 展开更多
关键词 Burned area mapping Moderate Resolution Imaging Spectroradiameter (MODIS) Global Environmental Monitoring Index(GEMI) Burned area Index (BAI)
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Localization and mapping in urban area based on 3D point cloud of autonomous vehicles 被引量:2
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作者 王美玲 李玉 +2 位作者 杨毅 朱昊 刘彤 《Journal of Beijing Institute of Technology》 EI CAS 2016年第4期473-482,共10页
In order to meet the application requirements of autonomous vehicles, this paper proposes a simultaneous localization and mapping (SLAM) algorithm, which uses a VoxelGrid filter to down sample the point cloud data, ... In order to meet the application requirements of autonomous vehicles, this paper proposes a simultaneous localization and mapping (SLAM) algorithm, which uses a VoxelGrid filter to down sample the point cloud data, with the combination of iterative closest points (ICP) algorithm and Gaussian model for particles updating, the matching between the local map and the global map to quantify particles' importance weight. The crude estimation by using ICP algorithm can find the high probability area of autonomous vehicles' poses, which would decrease particle numbers, increase algorithm speed and restrain particles' impoverishment. The calculation of particles' importance weight based on matching of attribute between grid maps is simple and practicable. Experiments carried out with the autonomous vehicle platform validate the effectiveness of our approaches. 展开更多
关键词 simultaneous localization and mapping (SLAM) Rao-Blackwellized particle filter RB-PF) VoxelGrid filter ICP algorithm Gaussian model urban area
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Different people,different wild:Comparing and mapping wilderness representation in Wuyishan National Park,China
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作者 Aifang Weng Lingyun Liao +7 位作者 Yue Cao Steve Carver Li Lin Siyuan Shen Zhengduo Xu Jianwen Dong Siren Lan Rui Yang 《Geography and Sustainability》 CSCD 2024年第1期144-156,共13页
It is essential to better integrate wilderness representations of different stakeholders into wilderness conservation.The way in which local residents and other stakeholders frame the construction of wilderness of pro... It is essential to better integrate wilderness representations of different stakeholders into wilderness conservation.The way in which local residents and other stakeholders frame the construction of wilderness of protected areas in developing countries are poorly understood.In these areas,land use policy and decision may lead to conflicts.This study aims to explore existing public wilderness representations using a questionnaire survey(n=514)administered amongst tourists and other stakeholders in the Wuyishan National Park,in southeast China.The spatial differences in public representations of wilderness across different stakeholder groups were compared against expert knowledge.We found that integrated wilderness representation maps of different stakeholder groups were consistent,namely'area where wild animals live','area with no human influence','a barren and lonely area'.However,three sub-representations of the individual stakeholders varied significantly.Moreover,expert-based wilderness mapping did not reflect public representations accurately,and an integrated wilder-ness quality map considering wilderness representations across both stakeholders and experts can better identify detailed wilderness areas.Our study provides new insights and technical support for future exploration of wilder-ness conservation and mapping in China and other countries with insufficient awareness of wilderness values and investigations in a regional scale. 展开更多
关键词 Wilderness mapping Public participation Environment perception Protected areas
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Application of Different Image Processing Techniques on Aster and ETM+ Images for Exploration of Hydrothermal Alteration Associated with Copper Mineralizations Mapping Kehdolan Area (Eastern Azarbaijan Province-Iran) 被引量:2
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作者 Golchin Hajibapir Mohammad Lotfi +1 位作者 Afshar Zia Zarifi Nima Nezafati 《Open Journal of Geology》 2014年第11期582-597,共16页
The Kehdolan area is located at 20 kilometers to the?south-east of Dozdozan Town (Eastern Azarbaijan Province). According to structural geology, volconic rocks are situated in Alborz-Azarbyjan zone, and faults?are?obs... The Kehdolan area is located at 20 kilometers to the?south-east of Dozdozan Town (Eastern Azarbaijan Province). According to structural geology, volconic rocks are situated in Alborz-Azarbyjan zone, and faults?are?observed?in?the?same direction to this system with SE-NW trend. The results show that kaolinite alteration trend with Argilic and propylitic veins?is the?same direction with SW-NE faults in this area. Therefore, these faults with these trends can be considered as the mineralization control for determination of the alterations. Different image processing techniques,?such as false color composite?(FCC), band ratios, color ratio composite?(CRC), principal component?analysis?(PCA), Crosta technique, supervised spectral angle mapping?(SAM), are used for?identification of the alteration zones associated with copper mineralization. In this project ASTER?data are process and spectral analysis to fit for recognizing intensity and kind of argillic, propylitic,?philic, and ETM+ data?which?are process and to fit for iron oxide and relation to metal mineralization of the area. For recognizing different alterations of the study area, some chemical and mineralogical analysis data from the samples showed that ASTER data and ETM+ data were?capable of hydrothermal alteration mapping with copper mineralization.?Copper mineralization in the region is in agreement with argillic alteration. SW-NE trending faults controlled the mineralization process. 展开更多
关键词 Kehdolan area False COLOR COMPOSITE Band Ratios COLOR Ratio COMPOSITE Principal Component Analysis Crosta Technique Supervised Spectral Angle mapping ASTER DATA ETM+ DATA Alteration
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On the Estimates of Hyperbolic Area Distortion of Quasiconformal Mappings 被引量:1
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作者 CHEN Xing-di HUANG Xin-zhong 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2007年第1期137-142,共6页
The distortion property of hyperbolic area of planar quasiconformal mappings is studied in this paper. In the case of radial quasiconformal mappings and angular deformed quasiconformal mappings their hyperbolic area d... The distortion property of hyperbolic area of planar quasiconformal mappings is studied in this paper. In the case of radial quasiconformal mappings and angular deformed quasiconformal mappings their hyperbolic area distortions are estimated quite sharply. The result can be applied to judge whether the hyperbolic area of a planar subset is explodable. 展开更多
关键词 hyperbolic area quasiconformal mapping explodable set distortion estimate
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A Co-Point Mapping-Based Approach to Drivable Area Detection for Self-Driving Cars 被引量:5
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作者 Ziyi Liu Siyu Yu Nanning Zheng 《Engineering》 2018年第4期479-490,共12页
The randomness and complexity of urban traffic scenes make it a difficult task for self-driving cars to detect drivable areas, Inspired by human driving behaviors, we propose a novel method of drivable area detection ... The randomness and complexity of urban traffic scenes make it a difficult task for self-driving cars to detect drivable areas, Inspired by human driving behaviors, we propose a novel method of drivable area detection for self-driving cars based on fusing pixel information from a monocular camera with spatial information from a light detection and ranging (LIDAR) scanner, Similar to the bijection of collineation, a new concept called co-point mapping, which is a bijection that maps points from the LIDAR scanner to points on the edge of the image segmentation, is introduced in the proposed method, Our method posi- tions candidate drivable areas through self-learning models based on the initial drivable areas that are obtained by fusing obstacle information with superpixels, In addition, a fusion of four features is applied in order to achieve a more robust performance, In particular, a feature called drivable degree (DD) is pro- posed to characterize the drivable degree of the LIDAR points, After the initial drivable area is characterized by the features obtained through self-learning, a Bayesian framework is utilized to calculate the final probability map of the drivable area, Our approach introduces no common hypothesis and requires no training steps; yet it yields a state-of-art performance when tested on the ROAD-KITTI benchmark, Experimental results demonstrate that the proposed method is a general and efficient approach for detecting drivable area, 展开更多
关键词 Drivable area SELF-DRIVING Data fusion Co-point mapping
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Geospatial susceptibility mapping of earthquake-induced landslides in Nuweiba area, Gulf of Aqaba, Egypt 被引量:1
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作者 Sara ABUZIED Samia IBRAHIM +1 位作者 Mona KAISER Tarek Saleem 《Journal of Mountain Science》 SCIE CSCD 2016年第7期1286-1303,共18页
Earthquake induced landslides are one of the most severe geo-environmental hazards that cause enormous damage to infrastructure, property, and loss of life in Nuweiba area. This study developed a model for mapping the... Earthquake induced landslides are one of the most severe geo-environmental hazards that cause enormous damage to infrastructure, property, and loss of life in Nuweiba area. This study developed a model for mapping the earthquake-induced landslide susceptibility in Nuweiba area in Egypt with considerations of geological, geomorphological, topographical, and seismological factors. An integrated approach of remote sensing and GIS technologies were applied for that target. Several data sources including Terra SAR-X and SPOT 5 satellite imagery, topographic maps, field data, and other geospatial resources were used to model landslide susceptibility. These data were used specifically to produce important thematic layers contributing to landslide occurrences in the region. A rating scheme was developed to assign ranks for the thematic layers and weights for their classes based on their contribution in landslide susceptibility. The ranks and weights were defined based on the knowledge from field survey and authors experiences related to the study area. The landslide susceptibility map delineates the hazard zones to three relative classes of susceptibility: high, moderate, and low. Therefore, the current approach provides a way to assess landslide hazards and serves for geo-hazard planning and prediction in Nuweiba area. 展开更多
关键词 Geographic Information Systems(GIS) Remote Sensing(RS) Landslides Susceptibility mapping Weights Nuweiba area
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Preoperative functional MRI localization of language areas in Chinese patients with brain tumors Validation with intraoperative electrocortical mapping
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作者 Hechun Xia Wei Huang +5 位作者 Liang Wu Hui Ma Xiaodong Wang Xuexin Chen Shengyu Sun Xiaoxiong Jia 《Neural Regeneration Research》 SCIE CAS CSCD 2012年第20期1563-1569,共7页
Ten Chinese patients with brain tumors involving language regions were selected. Preoperative functional MRI was performed to locate Broca's or Wernicke's area, and the cortex that was essential for language functio... Ten Chinese patients with brain tumors involving language regions were selected. Preoperative functional MRI was performed to locate Broca's or Wernicke's area, and the cortex that was essential for language function was determined by electrocortical mapping. A site-by-site comparison between functional MRI and electrocortical mapping was performed with the aid of a neuronavigation device. Results showed that the sensitivity and specificity of preoperative functional MRI were 80.0% and 85.0% in Broca's area and 66.6% and 85.2% in Wemicke's area, respectively. These experimental findings indicate that functional MRI is an accurate, reliable technique with which to identify the location of Wernicke's area or Broca's area in patients with brain tumors. 展开更多
关键词 functional MRI brain tumor Chinese language brain mapping intraoperative electrocorticalmapping Wernicke's area Broca's area regeneration neural regeneration
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Weighted Integral Means of Mixed Areas and Lengths Under Holomorphic Mappings
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作者 Jie Xiao Wen Xu 《Analysis in Theory and Applications》 2014年第1期1-19,共19页
This note addresses monotonic growths and logarithmic convexities of the weighted ((1-t2)αdt2, -∞〈α〈∞, 0〈t〈1) integral means Aα,β( f ,·) and Lα,β( f ,·) of the mixed area (πr2)-βA( f... This note addresses monotonic growths and logarithmic convexities of the weighted ((1-t2)αdt2, -∞〈α〈∞, 0〈t〈1) integral means Aα,β( f ,·) and Lα,β( f ,·) of the mixed area (πr2)-βA( f ,r) and the mixed length (2πr)-βL( f ,r) (0≤β≤1 and 0〈r〈1) of f (rD) and?f (rD) under a holomorphic map f from the unit disk D into the finite complex plane C. 展开更多
关键词 Monotonic growth logarithmic convexity mean mixed area mean mixed length isoperimetric inequality holomorphic map univalent function.
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Object-Based Burned Area Mapping with Extreme Gradient Boosting Using Sentinel-2 Imagery
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作者 Dimitris Stavrakoudis Ioannis Z. Gitas 《Journal of Geographic Information System》 2023年第1期53-72,共20页
The Sentinel-2 satellites are providing an unparalleled wealth of high-resolution remotely sensed information with a short revisit cycle, which is ideal for mapping burned areas both accurately and timely. This paper ... The Sentinel-2 satellites are providing an unparalleled wealth of high-resolution remotely sensed information with a short revisit cycle, which is ideal for mapping burned areas both accurately and timely. This paper proposes an automated methodology for mapping burn scars using pairs of Sentinel-2 imagery, exploiting the state-of-the-art eXtreme Gradient Boosting (XGB) machine learning framework. A large database of 64 reference wildfire perimeters in Greece from 2016 to 2019 is used to train the classifier. An empirical methodology for appropriately sampling the training patterns from this database is formulated, which guarantees the effectiveness of the approach and its computational efficiency. A difference (pre-fire minus post-fire) spectral index is used for this purpose, upon which we appropriately identify the clear and fuzzy value ranges. To reduce the data volume, a super-pixel segmentation of the images is also employed, implemented via the QuickShift algorithm. The cross-validation results showcase the effectiveness of the proposed algorithm, with the average commission and omission errors being 9% and 2%, respectively, and the average Matthews correlation coefficient (MCC) equal to 0.93. 展开更多
关键词 Operational Burned area mapping Sentinel-2 Extreme Gradient Boosting (XGB) QuickShift Segmentation Machine Learning
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Mapping the vegetation distribution of the permafrost zone on the Qinghai-Tibet Plateau 被引量:30
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作者 WANG Zhi-wei WANG Qian +12 位作者 ZHAO Lin WU Xiao-dong YUE Guang-yang ZOU De-fu NAN Zhuo-tong LIU Guang-yue PANG Qiang-qiang FANG Hong-bing WU Tong-hua SHI Jian-zong JIAO Ke-qin ZHAO Yong-hua ZHANG Le-le 《Journal of Mountain Science》 SCIE CSCD 2016年第6期1035-1046,共12页
In this paper, an updated vegetation map of the permafrost zone in the Qinghai-Tibet Plateau (QTP) was delineated. The vegetation map model was extracted from vegetation sampling with remote sensing (RS) datasets ... In this paper, an updated vegetation map of the permafrost zone in the Qinghai-Tibet Plateau (QTP) was delineated. The vegetation map model was extracted from vegetation sampling with remote sensing (RS) datasets by decision tree method. The spatial resolution of the map is 1 km×1 kin, and in it the alpine swamp meadow is firstly distinguished in the high-altitude areas. The results showed that the total vegetated area in the permafrost zone of the QTP is 1,201,751 km2. In the vegetated region, 50,260 km2 is the areas of alpine swamp meadow, 583,909 km2 for alpine meadow, 332,754 km2 for alpine steppe, and 234,828 km2 for alpine desert. This updated vegetation map in permafrost zone of QTP could provide more details about the distribution of alpine vegetation types for studying the vegetation mechanisms in the land surface processes of highaltitude areas. 展开更多
关键词 High-altitude areas Alpine vegetationtype Vegetation map Alpine swamp meadow MODIS Decision tree
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Landslide mapping and analysis along the China-Pakistan Karakoram Highway based on SBAS-InSAR detection in 2017 被引量:6
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作者 SU Xiao-jun ZHANG Yi +9 位作者 MENG Xing-min YUE Dong-xia MA Jin-hui GUO Fu-yun ZHOU Zi-qiang REHMAN Mohib Ur KHALID Zainab CHEN Guan ZENG Run-qiang ZHAO Fu-meng 《Journal of Mountain Science》 SCIE CSCD 2021年第10期2540-2564,共25页
The Karakoram Highway(KKH),a part of the China–Pakistan Economic Corridor(CPEC),is a major highway connecting northern Pakistan to China.The inventorying and analysis of landslides along KKH are challenging because o... The Karakoram Highway(KKH),a part of the China–Pakistan Economic Corridor(CPEC),is a major highway connecting northern Pakistan to China.The inventorying and analysis of landslides along KKH are challenging because of poor accessibility,vast study area,limited availability of ground-based datasets,and the complexity of landslide processes in the region.In order to preserve life,property,and infrastructure,and to enable the uninterrupted and efficient operation of the KKH,it is essential to strengthen measures for the prevention and control of geological disasters.In the present study,SBASInSAR(Small Baseline Subsets-Interferometric Synthetic Aperture Radar)was used to process 150 scenes of Sentinel 1-A images in the year 2017 along the Karakoram Highway.A total of 762 landslides,including 57 complex landslides,126 rock falls,167 debris slides,and 412 unstable slopes,ranging in size between 0.0017 and 10.63 km2 were identified.Moreover,this study also gains an inventory of 40 active glacier movements in this region.Landslide categorization,displacements characteristics,spatial distribution,and their relationship with various contributing factors have been successfully investigated along the entire KKH using image interpretation and frequency-area statistics.The criteria adopted for landslides categorization is presented in the study.The results showed that the 2-D ground deformation derived in Hunza valley echoes well with the general regional landslides characteristics.The spatial distribution analysis revealed that there are clumped distributions of landslides in the Gaizi,Tashkurgan,and Khunjerab in China,as well as in Hunza valley,and north of Chilas city in Pakistan.Statistical results indicated that these landslides mainly occur on south-facing slopes with a slope angle of 20°–45°and elevation relief of 550–2,100 m.Landslide development is also related to low vegetation cover and weathering effects in mountain gullies.Overall,our study provides scientific data support and theoretical references for prevention,control,and mitigation of geological disasters in the Karakoram region. 展开更多
关键词 Landslides mapping Slope deformation Identification Landslide development area development ratio SBAS-InSAR Karakoram Highway
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Application of the Regulations on Drawing of a Safe Firing Area Map in Weather Modification Operation 被引量:1
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作者 Wang Xiaoli Wang Tianru +3 位作者 Zhang Na Xu Tai’an Lu Dan Zhang Xiuzhen 《Meteorological and Environmental Research》 CAS 2017年第1期31-32,共2页
Technology for safe firing area maps was introduced firstly,and then potential danger after the launching of shells by an antiaircraft gun and a rocket was analyzed.Finally,problems in the process of applying the regu... Technology for safe firing area maps was introduced firstly,and then potential danger after the launching of shells by an antiaircraft gun and a rocket was analyzed.Finally,problems in the process of applying the regulations and their solutions were discussed.The application of safe firing area maps can provide technical support for the efficient development of weather modification operation. 展开更多
关键词 WEATHER modification operation SAFE FIRING area maps REGULATIONS APPLICATION China
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PARAMETRIC REPRESENTATIONS OF QUASICONFORMAL MAPPINGS 被引量:1
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作者 Zhenlian LIN Qingtian SHI 《Acta Mathematica Scientia》 SCIE CSCD 2020年第6期1874-1882,共9页
In this article,we first give two simple examples to illustrate that two types of parametric representation of the family ofΣ0 K have some gaps.Then we also find that the area derivative formula(1.6),which is used to... In this article,we first give two simple examples to illustrate that two types of parametric representation of the family ofΣ0 K have some gaps.Then we also find that the area derivative formula(1.6),which is used to estimate the area distortion ofΣ0 K,cannot be derived from[6],but that formula still holds forΣ0 K through our amendatory parametric representation for the one obtained by Eremenko and Hamilton. 展开更多
关键词 quasiconformal mapping Σ0 K parametric representation area distortion theorem Cauchy transformation
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Grayscale Mapping of Historically Irrigated LandsUsing GIS
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作者 Thomas C. Turney 《Journal of Geographic Information System》 2012年第1期33-36,共4页
This document describes the use of grayscale mapping and GIS for identification of historical irrigated lands. Historical irrigated lands form the basis for water rights—a private property right in New Mexico that is... This document describes the use of grayscale mapping and GIS for identification of historical irrigated lands. Historical irrigated lands form the basis for water rights—a private property right in New Mexico that is bought and sold on the open market. Identification of irrigated land on historical photography is both a science and an art. Grayscale mapping of historic black and white photographs can aid in the identification of irrigated lands. GIS allows historical images to be geo-referenced and area computations to be performed on polygons that define the irrigated lands. 展开更多
关键词 GIS Geo-Referencing Images Water RIGHTS Irrigation area COMPUTATIONS GRAYSCALE mapping
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