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Large-scale modelling wind damage vulnerability through combination of high-resolution forest resources maps and ForestGALES
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作者 Morgane Merlin Tommaso Locatelli +1 位作者 Barry Gardiner Rasmus Astrup 《Forest Ecosystems》 2025年第5期1021-1034,共14页
Assessing forest vulnerability to disturbances at a high spatial resolution and for regional and national scales has become attainable with the combination of remote sensing-derived high-resolution forest maps and mec... Assessing forest vulnerability to disturbances at a high spatial resolution and for regional and national scales has become attainable with the combination of remote sensing-derived high-resolution forest maps and mechanistic risk models. This study demonstrated large-scale and high-resolution modelling of wind damage vulnerability in Norway. The hybrid mechanistic wind damage model, ForestGALES, was adapted to map the critical wind speeds(CWS) of damage across Norway using a national forest attribute map at a 16 m × 16 m spatial resolution. P arametrization of the model for the Norwegian context was done using the literature and the National Forest Inventory data. This new parametrization of the model for Norwegian forests yielded estimates of CWS significantly different from the default parametrization. Both parametrizations fell short of providing acceptable discrimination of the damaged area following the storm of November 19, 2021 in the central southern region of Norway when using unadjusted CWS. After adjusting the CWS and the storm wind speeds by a constant factor, the Norwegian parametrization provided acceptable discrimination and was thus defined as suitable to use in future studies, despite the lack of field-and laboratory experiments to directly derive parameters for Norwegian forests. The windstorm event used for model validation in this study highlighted the challenges of predicting wind damage to forests in landscapes with complex topography. Future studies should focus on further developing ForestGALES and new datasets describing extreme wind climates to better represent the wind and tree interactions in complex topography, and predict the level of risk in order to develop local climate-smart forest management strategies. 展开更多
关键词 WIND Natural disturbance ForestGALES Damage probability Forest resource map
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Large-scale 3D Semantic Mapping Using Stereo Vision 被引量:1
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作者 Yi Yang Fan Qiu +3 位作者 Hao Li Lu Zhang Mei-Ling Wang Meng-Yin Fu 《International Journal of Automation and computing》 EI CSCD 2018年第2期194-206,共13页
In recent years, there have been a lot of interests in incorporating semantics into simultaneous localization and mapping (SLAM) systems. This paper presents an approach to generate an outdoor large-scale 3D dense s... In recent years, there have been a lot of interests in incorporating semantics into simultaneous localization and mapping (SLAM) systems. This paper presents an approach to generate an outdoor large-scale 3D dense semantic map based on binocular stereo vision. The inputs to system are stereo color images from a moving vehicle. First, dense 3D space around the vehicle is constructed, and tile motion of camera is estimated by visual odometry. Meanwhile, semantic segmentation is performed through the deep learning technology online, and the semantic labels are also used to verify tim feature matching in visual odometry. These three processes calculate the motion, depth and semantic label of every pixel in the input views. Then, a voxel conditional random field (CRF) inference is introduced to fuse semantic labels to voxel. After that, we present a method to remove the moving objects by incorporating the semantic labels, which improves the motion segmentation accuracy. The last is to generate tile dense 3D semantic map of an urban environment from arbitrary long image sequence. We evaluate our approach on KITTI vision benchmark, and the results show that the proposed method is effective. 展开更多
关键词 Semantic map stereo vision motion segmentation visual odometry simultaneous localization and mapping (SLAM).
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A robust method for large-scale route optimization on lunar surface utilizing a multi-level map model
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作者 Yutong JIA Shengnan ZHANG +5 位作者 Bin LIU Kaichang DI Bin XIE Jing NAN Chenxu ZHAO Gang WAN 《Chinese Journal of Aeronautics》 2025年第3期134-150,共17页
As we look ahead to future lunar exploration missions, such as crewed lunar exploration and establishing lunar scientific research stations, the lunar rovers will need to cover vast distances. These distances could ra... As we look ahead to future lunar exploration missions, such as crewed lunar exploration and establishing lunar scientific research stations, the lunar rovers will need to cover vast distances. These distances could range from kilometers to tens of kilometers, and even hundreds and thousands of kilometers. Therefore, it is crucial to develop effective long-range path planning for lunar rovers to meet the demands of lunar patrol exploration. This paper presents a hierarchical map model path planning method that utilizes the existing high-resolution images, digital elevation models and mineral abundance maps. The objective is to address the issue of the construction of lunar rover travel costs in the absence of large-scale, high-resolution digital elevation models. This method models the reference and semantic layers using the middle- and low-resolution remote sensing data. The multi-scale obstacles on the lunar surface are extracted by combining the deep learning algorithm on the high-resolution image, and the obstacle avoidance layer is modeled. A two-stage exploratory path planning decision is employed for long-distance driving path planning on a global–local scale. The proposed method analyzes the long-distance accessibility of various areas of scientific significance, such as Rima Bode. A high-precision digital elevation model is created using stereo images to validate the method. Based on the findings, it can be observed that the entire route spans a distance of 930.32 km. The route demonstrates an impressive ability to avoid meter-level impact craters and linear structures while maintaining an average slope of less than 8°. This paper explores scientific research by traversing at least seven basalt units, uncovering the secrets of lunar volcanic activities, and establishing ‘golden spike’ reference points for lunar stratigraphy. The final result of path planning can serve as a valuable reference for the design, mission demonstration, and subsequent project implementation of the new manned lunar rover. 展开更多
关键词 Crewed lunar exploration Long-range path planningi Multi-level map Deep learning Volcanic activities
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Virtual network mapping algorithm for large-scale network environment
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作者 张顺利 邱雪松 孟洛明 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2012年第4期55-63,共9页
A major challenge of network virtualization is the virtual network resource allocation problem that deals with efficient mapping of virtual nodes and virtual links onto the substrate network resources. However, the ex... A major challenge of network virtualization is the virtual network resource allocation problem that deals with efficient mapping of virtual nodes and virtual links onto the substrate network resources. However, the existing algorithms are almost concentrated on the randomly small-scale network topology, which is not suitable for practical large-scale network environments, because more time is spent on traversing SN and VN, resulting in VN requests congestion. To address this problem, virtual network mapping algorithm is proposed for large-scale network based on small-world characteristic of complex network and network coordinate system. Compared our algorithm with algorithm D-ViNE, experimental results show that our algorithm improves the overall performance. 展开更多
关键词 network virtualization virtual network mapping complex network network coordinate system simulated annealing algorithm
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Large-scale urban building function mapping by integrating multi-source web-based geospatial data
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作者 Wei Chen Yuyu Zhou +1 位作者 Eleanor C.Stokes Xuesong Zhang 《Geo-Spatial Information Science》 CSCD 2024年第6期1785-1799,共15页
Morphological(e.g.shape,size,and height)and function(e.g.working,living,and shopping)information of buildings is highly needed for urban planning and management as well as other applications such as city-scale buildin... Morphological(e.g.shape,size,and height)and function(e.g.working,living,and shopping)information of buildings is highly needed for urban planning and management as well as other applications such as city-scale building energy use modeling.Due to the limited availability of socio-economic geospatial data,it is more challenging to map building functions than building morphological information,especially over large areas.In this study,we proposed an integrated framework to map building functions in 50 U.S.cities by integrating multi-source web-based geospatial data.First,a web crawler was developed to extract Points of Interest(POIs)from Tripadvisor.com,and a map crawler was developed to extract POIs and land use parcels from Google Maps.Second,an unsupervised machine learning algorithm named OneClassSVM was used to identify residential buildings based on landscape features derived from Microsoft building footprints.Third,the type ratio of POIs and the area ratio of land use parcels were used to identify six non-residential functions(i.e.hospital,hotel,school,shop,restaurant,and office).The accuracy assessment indicates that the proposed framework performed well,with an average overall accuracy of 94%and a kappa coefficient of 0.63.With the worldwide coverage of Google Maps and Tripadvisor.com,the proposed framework is transferable to other cities over the world.The data products generated from this study are of great use for quantitative city-scale urban studies,such as building energy use modeling at the single building level over large areas. 展开更多
关键词 Building functions geospatial data TripAdvisor Google Static maps
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Application of GPS RTK in Surveying and Mapping of Large-scale Topographic Map
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作者 LI Shixiong SHA Ying 《外文科技期刊数据库(文摘版)工程技术》 2021年第6期108-110,共5页
GPS-RTK technology in topographic mapping has a relatively large advantage, this paper studies how to use the technology to carry out large-scale topographic mapping work, research the use of the method of precautions... GPS-RTK technology in topographic mapping has a relatively large advantage, this paper studies how to use the technology to carry out large-scale topographic mapping work, research the use of the method of precautions, surveying and mapping work methods, combined with examples to discuss the specific mapping process, to help surveying and mapping personnel to strengthen the quality control of surveying and mapping. 展开更多
关键词 GPS-RTK large scale map surveying and mapping APPLICATION
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3.0T磁共振T2 mapping序列联合血清新饱食分子蛋白1水平检测在老年膝关节早期骨关节炎诊断中的应用价值
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作者 唐利 巩玉荣 +2 位作者 曾立叶 高艳芳 邓成哲 《实用医学杂志》 北大核心 2025年第8期1238-1242,共5页
目的探讨3.0 T磁共振(MRI)T2 mapping序列联合血清新饱食分子蛋白1(nesfatin-1)水平对老年膝关节早期骨关节炎(OA)的诊断价值。方法选取2023年5月至2024年5月医院收治的膝关节OA的97例老年患者(OA组)和52例同期老年体检者(对照组),根据... 目的探讨3.0 T磁共振(MRI)T2 mapping序列联合血清新饱食分子蛋白1(nesfatin-1)水平对老年膝关节早期骨关节炎(OA)的诊断价值。方法选取2023年5月至2024年5月医院收治的膝关节OA的97例老年患者(OA组)和52例同期老年体检者(对照组),根据X线结果将膝关节OA组分为早期组和非早期组,均接受3.0T MRI T2 mapping序列扫描检测膝关节软骨区域T2值,检测血清nesfatin-1水平,比较上述指标差异并采用ROC曲线分析其对老年膝关节早期OA的诊断价值。结果97例老年膝关节OA患者中,早期组35例,非早期组62例,OA组患者膝关节5个软骨区域的T2值及nesfatin-1血清均高于对照组(P<0.05),早期组均低于非早期组(P<0.05);膝关节软骨区域T2值和血清nesfatin-1水平单独诊断早期OA的AUC在0.774~0.871范围,联合诊断的AUC为0.939。结论3.0 T磁共振T2 mapping序列联合血清nesfatin-1水平检测对老年膝关节早期OA具有较高的诊断价值。 展开更多
关键词 膝关节早期骨关节炎 老年 磁共振 T2 mapping序列 新饱食分子蛋白1
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MR T_(1)-mapping结合动脉自旋标记技术在评估儿童慢性肾脏病肾纤维化和灌注中的应用 被引量:1
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作者 赵佳佳 胡俊 +2 位作者 尹传高 顾东浩 朱晓冬 《临床放射学杂志》 北大核心 2025年第3期513-517,共5页
目的初步研究MR纵向弛豫时间定量成像(T 1-mapping)和动脉自旋标记技术(ASL)在诊断儿童慢性肾脏病(CKD)中的应用价值。方法纳入CKD患儿32例(包括肾脏未萎缩19例,萎缩13例),同期招募健康志愿者30名作对照组,行T 1-mapping和ASL序列扫描,... 目的初步研究MR纵向弛豫时间定量成像(T 1-mapping)和动脉自旋标记技术(ASL)在诊断儿童慢性肾脏病(CKD)中的应用价值。方法纳入CKD患儿32例(包括肾脏未萎缩19例,萎缩13例),同期招募健康志愿者30名作对照组,行T 1-mapping和ASL序列扫描,分别获得肾皮质T 1值和肾皮质血流量(RBF)。比较对照组和CKD组患儿肾皮质T 1值和RBF值的差异,并分析CKD组肾皮质T 1值和RBF值与估算肾小球滤过率(eGFR)、血肌酐(Scr)、血胱抑素C(Cys-C)的相关性。结果CKD组较对照组肾皮质T 1值明显升高、RBF值明显减低(P<0.05);CKD组中,肾脏未萎缩患儿肾皮质T 1值与eGRF、Scr、Cys-C呈高、中度相关(r=-0.832、0.777、0.698,P<0.05),肾脏萎缩患儿肾皮质T 1值与eGRF、Scr呈高度相关(r=0.726、-0.743,P<0.05);CKD组肾皮质RBF与eGRF、Cys-C、Scr呈中度相关(r=0.699、-0.619、-0.554,P<0.05)。结论MR T_(1)-mapping和ASL定量反映肾脏微观病理变化及血流灌注情况,具有预测肾脏慢性病理损伤的潜在价值,有望在肾脏发生不可逆损伤前早期、无创地提供肾脏功能信息。 展开更多
关键词 慢性肾脏病 儿童 T_(1)-mapping 动脉自旋标记 磁共振功能成像
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基于磁共振T1 mapping影像组学胰腺导管腺癌间质比定量评估模型的开发与临床验证
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作者 张心悦 陈成伟 +4 位作者 袁小涵 沈奕暄 陈士跃 边云 陆建平 《海军军医大学学报》 北大核心 2025年第12期1597-1603,共7页
目的开发基于MRI T1 mapping影像组学的胰腺导管腺癌(PDAC)间质含量无创评估模型。方法前瞻性纳入2023年6月至2024年12月海军军医大学第一附属医院157例经术后病理确诊的PDAC患者。从T1 mapping图像提取12442个特征并筛选出10个关键特征... 目的开发基于MRI T1 mapping影像组学的胰腺导管腺癌(PDAC)间质含量无创评估模型。方法前瞻性纳入2023年6月至2024年12月海军军医大学第一附属医院157例经术后病理确诊的PDAC患者。从T1 mapping图像提取12442个特征并筛选出10个关键特征,采用最小绝对收缩和选择算子回归对10个关键特征进行线性组合及加权计算,得到影像组学评分(Rad_Score)。采用Spearman秩相关检验Rad_Score与间质含量的相关性。以病理诊断的间质含量为金标准,通过ROC曲线评估Rad_Score的诊断效能。采用多重线性回归建立间质含量预测方程(纳入Rad_Score与肿瘤最大径),采用Bland-Altman法检验预测值与实际值的一致性。结果在PADC患者中Rad_Score与间质含量相关(rs=0.52,P<0.001),Rad_Score预测间质含量>0.5的AUC值为0.936(95%CI 0.885~0.987)、灵敏度为91.7%、特异度为88.0%。基于Rad_Score和肿瘤最大径构建的线性回归预测模型为:间质含量=0.592+0.037×Rad_Score-0.025×肿瘤最大径(cm);Bland-Altman法分析显示其预测的间质含量与实际值一致性较好(平均偏差为0.00,95%一致性界限为-0.33~0.33)。结论基于MRI T1 mapping影像组学建立的PDAC间质评估模型对高、低间质含量有较好的区分价值。 展开更多
关键词 磁共振成像 T1 mapping 胰腺导管腺癌 间质比 影像组学 深度学习 多模态 无创评估
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基于T_(2)mapping及超短回波时间技术定量探究早期膝骨关节炎的发病机制 被引量:2
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作者 牛飞格 孟祥虹 +1 位作者 孙曼 王植 《临床放射学杂志》 北大核心 2025年第2期350-356,共7页
目的基于浅表软骨的T_(2)mapping和骨软骨交界区(OCJ)的超短回波时间(UTE)T_(2)^(*)mapping探究膝骨关节炎(KOA)早期浅表软骨和骨软骨交界区的病变顺序。方法对纳入的30个健康膝和30个早期骨性关节炎膝进行常规和定量MRI扫描,主要扫描... 目的基于浅表软骨的T_(2)mapping和骨软骨交界区(OCJ)的超短回波时间(UTE)T_(2)^(*)mapping探究膝骨关节炎(KOA)早期浅表软骨和骨软骨交界区的病变顺序。方法对纳入的30个健康膝和30个早期骨性关节炎膝进行常规和定量MRI扫描,主要扫描序列包括三维水激发序列(3D WATS)、T_(2)mapping和UTE T_(2)^(*)mapping。将每个膝关节都分为股骨内侧髁、股骨外侧髁、胫骨内侧髁、胫骨外侧髁、髌骨和滑车区6个区域并测量每个区域的浅层软骨T_(2)值和OCJ T_(2)^(*)值。用独立样本t检验比较健康组和早期KOA组间的浅层软骨T_(2)值及OCJ T_(2)^(*)值。用Spearman相关性检验评估浅层软骨T_(2)值与OCJ T_(2)^(*)值间的相关性。结果早期KOA组的浅层软骨T_(2)值在股骨内侧髁(P<0.001)、胫骨内侧平台(P<0.001)、髌骨(P<0.001)和股骨滑车区(P=0.01)相对于健康组显著升高。早期KOA组OCJ T_(2)^(*)值在股骨内侧髁(P<0.001)、胫骨内侧平台(P<0.001)、胫骨外侧平台(P<0.001)、髌骨(P=0.001)和滑车区(P<0.001)均显著升高。浅层软骨T_(2)值和骨软骨交界区T_(2)^(*)值间存在正相关关系(r=0.37,P<0.001)。结论浅表软骨的T_(2)mapping和骨软骨交界区的UTE T_(2)^(*)mapping成像都可定量且无创识别早期KOA。在KOA早期,浅表软骨和OCJ都出现了生化改变。 展开更多
关键词 骨性关节炎 关节软骨骨软骨交界区 T_(2)mapping T_(2)^(*)mapping
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磁共振T2-mapping成像技术在膝关节骨性关节炎诊断中应用的研究进展
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作者 陈思 《黑龙江医学》 2025年第16期2042-2044,2048,共4页
T2-mapping成像技术通过分析软骨的T2弛豫时间,定量评估软骨组织学结构,揭示软骨中水含量和胶原纤维排列的变化,适用于早期检测软骨损伤和监测疾病进展,对评估软骨健康状况至关重要。T2-mapping成像技术不仅对膝关节骨性关节炎(KOA)的... T2-mapping成像技术通过分析软骨的T2弛豫时间,定量评估软骨组织学结构,揭示软骨中水含量和胶原纤维排列的变化,适用于早期检测软骨损伤和监测疾病进展,对评估软骨健康状况至关重要。T2-mapping成像技术不仅对膝关节骨性关节炎(KOA)的早期诊断和进展监测具有重要价值,还能在软骨修复过程中监测和评估软骨的生化变化。随着成像技术和数据处理能力的进一步发展,T2-mapping成像有望提高诊断精度、优化治疗方案,为KOA的管理和治疗带来革新。文章综述了磁共振成像技术(MRI)中的T2-mapping成像技术在KOA诊断和评估中的应用。 展开更多
关键词 磁共振T2-mapping成像 膝关节 骨性关节炎
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基于T2^(*)mapping的业余马拉松运动员足踝部关节软骨损伤及其影响因素分析 被引量:2
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作者 高雅丽 兰晓川 +2 位作者 王舒 宋凌恒 陈伟 《磁共振成像》 北大核心 2025年第2期94-99,共6页
目的基于T2^(*)mapping定量分析业余马拉松运动员足踝部关节软骨的T2^(*)值,并分析其与性别、年龄、身体质量指数(body mass index,BMI)、跑龄、跑量之间的相关性。材料与方法于2023年7月份至2023年9月份招募重庆市长跑运动爱好者48名,... 目的基于T2^(*)mapping定量分析业余马拉松运动员足踝部关节软骨的T2^(*)值,并分析其与性别、年龄、身体质量指数(body mass index,BMI)、跑龄、跑量之间的相关性。材料与方法于2023年7月份至2023年9月份招募重庆市长跑运动爱好者48名,其中跑量<300 km/月的36例(中低跑量组),跑量≥300 km/月的12例(高跑量组)。所有受试者均进行单侧无症状踝关节的MRI扫描,扫描序列包括T2^(*)mapping多回波自旋回波(spin echo,SE)序列矢状位、质子密度加权成像脂肪抑制(proton density-weighted imaging fat-saturated,PDWI-FS)序列矢状位、冠状位、横轴位以及T1加权脂肪抑制成像(T1-weighted imaging fat-saturated,T1WI-FS)序列横轴位。沿关节软骨轮廓边缘勾画距骨穹窿、跟骰关节跟骨面、骰骨面及后距下关节跟骨面、距骨面软骨作为感兴趣区(region of interest,ROI),获得相应的T2^(*)值。采用线性回归分析软骨T2^(*)值与年龄、BMI、跑龄的相关性,采用独立样本t检验分析不同跑量及不同性别间的软骨T2^(*)值差异。结果(1)距骨穹窿、跟骰关节跟骨面及骰骨面、后距下关节跟骨面及距骨面软骨T2^(*)值在性别上的差异均具有统计学意义(P=0.001、P<0.001、P=0.002、P=0.008、P=0.004);(2)高跑量组的距骨穹窿、后距下关节跟骨面软骨T2^(*)值高于中低跑量组(P=0.014、0.023),不同跑量的跟骰关节跟骨面及骰骨面、后距下关节距骨面软骨T2^(*)值的差异均无统计学意义(P=0.987、0.072、0.724);(3)距骨穹窿、跟骰关节跟骨面及骰骨面、后距下关节跟骨面、距骨面软骨T2^(*)值均与BMI呈正相关(r=0.376、0.384、0.300、0.422、0.455,P=0.005、0.004、0.019、0.001、0.001)。结论在业余马拉松运动员这一跑步群体中,与中低跑量相比,高跑量更有可能导致距骨穹窿、后距下关节跟骨面软骨损伤;而与较低的BMI相比,高BMI增加了距骨穹窿、跟骰关节跟骨面、骰骨面及后距下关节跟骨面、距骨面软骨损伤的风险。 展开更多
关键词 业余马拉松 跑步 软骨 磁共振成像 T2^(*)mapping
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心脏磁共振组织追踪及T1 mapping技术对糖尿病心肌损伤评估的应用研究 被引量:1
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作者 庞艳秋 万娜 +5 位作者 郭瑞 邓得峰 周浩 张凯 兰芳 马静 《磁共振成像》 北大核心 2025年第9期82-89,共8页
目的探讨心脏磁共振组织追踪(cardiac magnetic resonance tissue tracing,CMR-TT)技术及T1 mapping技术在2型糖尿病(type 2 diabetes mellitus,T2DM)患者心肌损伤评估中的应用价值。材料与方法前瞻性收集2023年12月至2025年4月在我院... 目的探讨心脏磁共振组织追踪(cardiac magnetic resonance tissue tracing,CMR-TT)技术及T1 mapping技术在2型糖尿病(type 2 diabetes mellitus,T2DM)患者心肌损伤评估中的应用价值。材料与方法前瞻性收集2023年12月至2025年4月在我院进行心脏磁共振检查的T2DM患者64例,健康对照(healthy controls,HC)32例。所有心脏磁共振图像数据导入专用软件进行分析,获取全心心肌应变参数、双心室功能参数以及左心室T1 mapping参数,采用t检验,Mann-Whitney U检验及卡方检验对两组间上述参数进行比较,采用Pearson及Spearman相关性分析心肌结构、功能与心肌应变的关联。结果T2DM组左心室心肌质量指数(left ventricular myocardial mass index,LVMI)、左心室重塑指数(left ventricular remodeling index,LVRI)增加(均P<0.001),左心室全局纵向应变(global longitudinal peak strain in the left ventricle,LV GLS)、右心室全局纵向应变降低(均P<0.05),T2DM组周向左心室收缩期峰值应变率(peak systolic strain rate of the left ventricle,LV PSSR)、纵向LV PSSR及左心室舒张期峰值应变率(diastolic peak strain rate of the left ventricle,LV PDSR)绝对值均降低(均P<0.019)。T2DM患者左心房/右心房(leftatrium/rightatrium,LA/RA)储存应变、LA/RA导管应变均降低(均P<0.001)。T2DM患者的细胞外容积(extracellular volume,ECV)较HC组升高(P<0.001)。双心室射血分数、收缩末期容积指数与双心室应变功能均相关(均P<0.003)。LVMI与左心室全局径向应变(global radial strain of the left ventricle,LV GRS)、左心室全局周向应变(global circumferential strain of the left ventricle,LV GCS)、LV GLS、周向LV PSSR、纵向LV PSSR、径向LV PDSR、周向LV PDSR、纵向LV PDSR相关(均P<0.021)。左心室舒张末期容积指数与LV GCS、LV GLS、周向LV PSSR、纵向LV PSSR、周向LV PDSR相关(均P<0.044)。右心室舒张末期容积指数与右心室全局周向应变相关(r=0.331,P=0.007)。LVRI与LV GLS及纵向LV PDSR相关(均P<0.01),且与径向LV PSSR弱相关(r=0.266,P=0.034)。结论T2DM患者全心心肌应变较对照组降低,ECV值升高,双心室心肌结构、功能与心肌应变相互关联,CMR-TT及T1 mapping技术可以有效检测糖尿病心肌损伤。 展开更多
关键词 糖尿病 糖尿病心肌病 磁共振成像 心脏磁共振 组织追踪 T1 mapping
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T2 Mapping评估颞下颌关节功能紊乱综合征患者关节盘特征的临床研究
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作者 和仕珍 韦晓玉 +3 位作者 刘晨 张莉 岳莉蓉 王鹏 《昆明医科大学学报》 2025年第6期96-102,共7页
目的运用磁共振T2 mapping技术,分别在开、闭口位定量评估TMD关节盘结构损伤的变化及意义。方法前瞻性收集2023年6月至2024年1月期间在云南大学附属医院口腔外科初诊为TMD的患者127例以及对照组51例。所试对象均行颞颌常规序列及T2 Mapp... 目的运用磁共振T2 mapping技术,分别在开、闭口位定量评估TMD关节盘结构损伤的变化及意义。方法前瞻性收集2023年6月至2024年1月期间在云南大学附属医院口腔外科初诊为TMD的患者127例以及对照组51例。所试对象均行颞颌常规序列及T2 Mapping序列扫描。扫描后利用后处理获得伪彩图,分别在开、闭口位伪彩图上测量关节盘(前带、后带)的T2值,分析其与TMD前移程度的相关性。结果病例组开、闭口位关节盘后带T2值均大于关节盘前带T2值(P<0.05);关节盘不同前移程度组,正常上位组、轻度前移组、中度前移组的T2值整体呈依次增高趋势,而重度前移组的T2值呈现下降的趋势(P<0.01);弹响、咬合异常是TMD患者关节盘不可复前移的独立危险因素。结论开口位、闭口位扫描均可以作为评估TMD关节盘损伤的检查方法;T2 mapping技术可以定量、敏感地反映关节盘微结构生化成分变化规律。 展开更多
关键词 颞下颌关节紊乱综合征 磁共振 T2 mapping 关节盘 颞下颌关节
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T2 mapping与3D-WATSc序列定量测量膝关节软骨体积的一致性 被引量:1
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作者 吴明杰 许亚飞 +2 位作者 傅孙亚 张玉琴 徐凌斌 《中国医学影像学杂志》 北大核心 2025年第3期320-325,共6页
目的探索T2 mapping与三维选择性水激发(3D-WATSc)序列测量膝关节软骨体积的一致性。资料与方法2022年5—12月宁波大学附属李惠利医院招募30名健康志愿者,行左膝关节3D-WATSc、T2mapping序列扫描。随机抽取20名受试者的T2 mapping序列,... 目的探索T2 mapping与三维选择性水激发(3D-WATSc)序列测量膝关节软骨体积的一致性。资料与方法2022年5—12月宁波大学附属李惠利医院招募30名健康志愿者,行左膝关节3D-WATSc、T2mapping序列扫描。随机抽取20名受试者的T2 mapping序列,分析8组不同TE(13、26、39、52、65、78、91、104 ms)的原始图像,由2名观察者对原始图像质量进行评分,使用Kappa检验观察评分一致性,Welch方差分析和Games-Howell text事后检验得出最佳图像质量的TE。基于T2 mapping和3D-WATSc序列对30名受试者股骨髁、胫骨平台和髌骨后缘软骨体积进行半自动分割测量,使用组内相关系数(ICC)、BlandAltman检验T2 mapping序列下2名观察者间及两种序列测得软骨体积的一致性。结果2名观察者评分除TE 104 ms一致性较差(Kappa=0.318)、TE 78 ms差异无统计学意义(P=0.052)外,其余一致性均为中等(Kappa>0.40,P<0.05),进一步分析TE 26 ms软骨显示质量评分最佳(均值2.90)。将TE 26 ms与其余7组评分进行Games-Howell text两两比较,除与TE 13 ms(均值2.55)、TE 39 ms(均值2.62)两组评分差异无统计学意义(P>0.05)外,TE 26 ms与其余TE组评分差异均有统计学意义(P均<0.05)。在T2 mapping(TR 2000 ms、TE 26 ms)序列上,2名观察者分割得到各部分软骨体积的ICC均>0.6,P<0.05,以股骨髁软骨体积的一致性最好(ICC=0.877,P<0.01)。两种序列测得的各部分软骨体积一致性均较好(ICC均>0.75,P均<0.01),以胫骨平台软骨体积的一致性最好(ICC=0.857,P<0.01)。结论T2 mapping原始图像(TR 2000 ms、TE 26 ms)可清晰显示膝关节软骨形态,T2 mapping与3D-WATSc序列定量膝关节软骨体积的一致性较好,T2 mapping单一序列可为膝关节软骨形态及功能的一站式定量分析提供可信的扫描方案。 展开更多
关键词 磁共振成像 T2 mapping 三维选择性水激发序列 膝关节 软骨 体积
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Landslide Susceptibility Mapping Using RBFN-Based Ensemble Machine Learning Models 被引量:1
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作者 Duc-Dam Nguyen Nguyen Viet Tiep +5 位作者 Quynh-Anh Thi Bui Hiep Van Le Indra Prakash Romulus Costache Manish Pandey Binh Thai Pham 《Computer Modeling in Engineering & Sciences》 SCIE EI 2025年第1期467-500,共34页
This study was aimed to prepare landslide susceptibility maps for the Pithoragarh district in Uttarakhand,India,using advanced ensemble models that combined Radial Basis Function Networks(RBFN)with three ensemble lear... This study was aimed to prepare landslide susceptibility maps for the Pithoragarh district in Uttarakhand,India,using advanced ensemble models that combined Radial Basis Function Networks(RBFN)with three ensemble learning techniques:DAGGING(DG),MULTIBOOST(MB),and ADABOOST(AB).This combination resulted in three distinct ensemble models:DG-RBFN,MB-RBFN,and AB-RBFN.Additionally,a traditional weighted method,Information Value(IV),and a benchmark machine learning(ML)model,Multilayer Perceptron Neural Network(MLP),were employed for comparison and validation.The models were developed using ten landslide conditioning factors,which included slope,aspect,elevation,curvature,land cover,geomorphology,overburden depth,lithology,distance to rivers and distance to roads.These factors were instrumental in predicting the output variable,which was the probability of landslide occurrence.Statistical analysis of the models’performance indicated that the DG-RBFN model,with an Area Under ROC Curve(AUC)of 0.931,outperformed the other models.The AB-RBFN model achieved an AUC of 0.929,the MB-RBFN model had an AUC of 0.913,and the MLP model recorded an AUC of 0.926.These results suggest that the advanced ensemble ML model DG-RBFN was more accurate than traditional statistical model,single MLP model,and other ensemble models in preparing trustworthy landslide susceptibility maps,thereby enhancing land use planning and decision-making. 展开更多
关键词 Landslide susceptibility map spatial analysis ensemble modelling information values(IV)
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Challenges in the Large-Scale Deployment of CCUS 被引量:2
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作者 Zhenhua Rui Lianbo Zeng Birol Dindoruk 《Engineering》 2025年第1期17-20,共4页
1.Introduction Climate change mitigation pathways aimed at limiting global anthropogenic carbon dioxide(CO_(2))emissions while striving to constrain the global temperature increase to below 2℃—as outlined by the Int... 1.Introduction Climate change mitigation pathways aimed at limiting global anthropogenic carbon dioxide(CO_(2))emissions while striving to constrain the global temperature increase to below 2℃—as outlined by the Intergovernmental Panel on Climate Change(IPCC)—consistently predict the widespread implementation of CO_(2)geological storage on a global scale. 展开更多
关键词 large-scale Deployment CCUS CHALLENGES Climate Change Mitigation
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3.0T MRI下肢神经T_(2) mapping和弥散张量成像定量诊断2型糖尿病周围神经病变的临床价值
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作者 寇梦琪 杨玉林 +4 位作者 黄国权 王可武 刘叶美 管绍羊 张维 《医学影像学杂志》 2025年第9期121-125,130,共6页
目的探讨3.0T MRI下肢神经T_(2)mapping和弥散张量成像(DTI)对2型糖尿病周围神经病变(DPN)的诊断价值。方法选取42例DPN患者(DPN组)、31例成年健康志愿者(对照组),分别测量坐骨神经、腘神经T_(2)mapping及同层面、相同部位皮下脂肪和周... 目的探讨3.0T MRI下肢神经T_(2)mapping和弥散张量成像(DTI)对2型糖尿病周围神经病变(DPN)的诊断价值。方法选取42例DPN患者(DPN组)、31例成年健康志愿者(对照组),分别测量坐骨神经、腘神经T_(2)mapping及同层面、相同部位皮下脂肪和周围肌肉T_(2)mapping、DTI参数(FA、AD、RD、RA)。比较两组坐骨神经、腘神经的量化指标差异。采用受试者工作特征(ROC)曲线分析各项指标对DPN的诊断效能。结果DPN组较对照组神经、肌肉T_(2)mapping及神经与脂肪、神经与肌肉T_(2)mapping比值升高,坐骨神经和腘神经的FA、RA降低,AD、RD升高(P均<0.05)。神经与脂肪T_(2)mapping比值的诊断效能最好(AUC=0.828),DTI各参数中AD的诊断效能最好(AUC=0.756)。神经与脂肪T_(2)mapping比值和AD联合的诊断效能更佳(AUC=0.868)。结论3.0T MRI下肢神经T_(2)mapping和DTI参数可定量诊断2型糖尿病周围神经病变,神经与脂肪T_(2)mapping比值和AD联合具有更好的诊断效能。 展开更多
关键词 2型糖尿病 糖尿病周围神经病变 磁共振成像 T_(2)mapping 弥散张量成像
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Localization of Mobile Robot Aided for Large-Scale Construction Based on Optimized Artificial Landmark Map in Ongoing Scene 被引量:2
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作者 Zhen Xu Shuai Guo +2 位作者 Tao Song Yuwen Li Lingdong Zeng 《Computer Modeling in Engineering & Sciences》 SCIE EI 2022年第3期1853-1882,共30页
The effectiveness of mobile robot aided for architectural construction depends strongly on its accurate localization ability.Localization of mobile robot is increasingly important for the printing of buildings in the ... The effectiveness of mobile robot aided for architectural construction depends strongly on its accurate localization ability.Localization of mobile robot is increasingly important for the printing of buildings in the construction scene.Although many available studies on the localization have been conducted,only a few studies have addressed the more challenging problem of localization for mobile robot in large-scale ongoing and featureless scenes.To realize the accurate localization of mobile robot in designated stations,we build an artificial landmark map and propose a novel nonlinear optimization algorithm based on graphs to reduce the uncertainty of the whole map.Then,the performances of localization for mobile robot based on the original and optimized map are compared and evaluated.Finally,experimental results show that the average absolute localization errors that adopted the proposed algorithm is reduced by about 21%compared to that of the original map. 展开更多
关键词 large-scale construction artificial landmark map LOCALIZATION mobile robot non-linear optimization
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Fine mapping of Pm71,a novel powdery mildew resistance gene from emmer wheat 被引量:6
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作者 Jiadong Zhang Hong Yang +10 位作者 Guohao Han Hongxing Xu Ruishan Liu Ningning Yu Ran Han Yaoxue Li Jiatong Li Yintao Dai Cheng Liu Yuli Jin Pengtao Ma 《The Crop Journal》 2025年第1期62-68,共7页
Powdery mildew negatively impacts wheat yield and quality.Emmer wheat(Triticum dicoccum),an ancestral species of common wheat,is a gene donor for wheat improvement.Cultivated emmer accession H1-707 exhibited all-stage... Powdery mildew negatively impacts wheat yield and quality.Emmer wheat(Triticum dicoccum),an ancestral species of common wheat,is a gene donor for wheat improvement.Cultivated emmer accession H1-707 exhibited all-stage resistance to powdery mildew over consecutive years.Genetic analysis of H1-707 at the seedling stage revealed a dominant monogenic inheritance pattern,and the underlying gene was designated Pm71.By employing bulked segregant exome sequencing(BSE-Seq)and using 2000 F2:3 families,Pm71 was fine mapped to a 336-kb interval on chromosome arm 6AS by referencing to the durum cv.Svevo RefSeq 1.0.Collinearity analysis revealed high homology in the candidate interval between Svevo and six Triticum species.Among six high-confidence genes annotated within this interval,TRITD6Av1G005050 encoding a GDSL esterase/lipase was identified as a key candidate for Pm71. 展开更多
关键词 Blumeria graminis BSE-Seq Disease resistance Fine mapping Triticum dicoccum
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