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Residual Attention-BiConvLSTM:一种新的全球电离层TEC map预测模型
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作者 王浩然 刘海军 +5 位作者 袁静 乐会军 李良超 陈羿 单维锋 袁国铭 《地球物理学报》 北大核心 2025年第2期413-430,共18页
电离层总电子含量(TEC)预测对提高全球卫星导航系统(GNSS)的精度具有重要意义.现有的TEC map预测模型主要通过顺序堆叠时空特征提取单元来实现.这种模型搭建方法会因多个卷积层顺序堆叠而损失细粒度的TEC map的空间特征,导致模型精度不... 电离层总电子含量(TEC)预测对提高全球卫星导航系统(GNSS)的精度具有重要意义.现有的TEC map预测模型主要通过顺序堆叠时空特征提取单元来实现.这种模型搭建方法会因多个卷积层顺序堆叠而损失细粒度的TEC map的空间特征,导致模型精度不够;还会由于多层堆叠导致梯度消失或梯度爆炸问题.本文借鉴残差注意力(Residual Attention)的思想,在TEC map预测模型中增加了残差注意力模块,提出了Residual Attention-BiConvLSTM模型.该模型中的残差注意力模块能同时提取粗、细粒度空间特征,并对其进行加权.本文在全球TEC map数据上与ConvLSTM、ConvGRU、ED-ConvLSTM和C1PG进行了对比实验.实验结果表明,本文所提出的Residual Attention-BiConvLSTM模型的RMSE、MAE、MAPE和R^(2)在太阳活动高年和年均优于对比模型.本文还在一次磁暴事件中对比了5种模型的预测效果.实验结果表明,大磁暴发生时,本文模型与C1PG相近,优于其他3种对比模型.本文的研究工作为电离层map预测模型搭建提供一个新思路. 展开更多
关键词 电离层TEC map预测 残差注意力模块 Residual Attention-BiConvLSTM 时空预测模型
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Leveraging ROTI map derived from Indonesian GNSS receiver network for advancing study of Equatorial Plasma Bubble in Southeast/East Asia 被引量:1
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作者 Prayitno Abadi Ihsan N.Muafiry +8 位作者 Teguh N.Pratama Angga Y.Putra Suraina Gatot H.Pramono Sidik T.Wibowo Febrylian F.Chabibi Umar A.Ahmad Wildan P.Tresna Asnawi 《Earth and Planetary Physics》 EI CAS 2025年第1期101-116,共16页
This paper highlights the crucial role of Indonesia’s GNSS receiver network in advancing Equatorial Plasma Bubble(EPB)studies in Southeast and East Asia,as ionospheric irregularities within EPB can disrupt GNSS signa... This paper highlights the crucial role of Indonesia’s GNSS receiver network in advancing Equatorial Plasma Bubble(EPB)studies in Southeast and East Asia,as ionospheric irregularities within EPB can disrupt GNSS signals and degrade positioning accuracy.Managed by the Indonesian Geospatial Information Agency(BIG),the Indonesia Continuously Operating Reference Station(Ina-CORS)network comprises over 300 GNSS receivers spanning equatorial to southern low-latitude regions.Ina-CORS is uniquely situated to monitor EPB generation,zonal drift,and dissipation across Southeast Asia.We provide a practical tool for EPB research,by sharing two-dimensional rate of Total Electron Content(TEC)change index(ROTI)derived from this network.We generate ROTI maps with a 10-minute resolution,and samples from May 2024 are publicly available for further scientific research.Two preliminary findings from the ROTI maps of Ina-CORS are noteworthy.First,the Ina-CORS ROTI maps reveal that the irregularities within a broader EPB structure persist longer,increasing the potential for these irregularities to migrate farther eastward.Second,we demonstrate that combined ROTI maps from Ina-CORS and GNSS receivers in East Asia and Australia can be used to monitor the development of ionospheric irregularities in Southeast and East Asia.We have demonstrated the combined ROTI maps to capture the development of ionospheric irregularities in the Southeast/East Asian sector during the G5 Geomagnetic Storm on May 11,2024.We observed simultaneous ionospheric irregularities in Japan and Australia,respectively propagating northwestward and southwestward,before midnight,whereas Southeast Asia’s equatorial and low-latitude regions exhibited irregularities post-midnight.By sharing ROTI maps from Indonesia and integrating them with regional GNSS networks,researchers can conduct comprehensive EPB studies,enhancing the understanding of EPB behavior across Southeast and East Asia and contributing significantly to ionospheric research. 展开更多
关键词 Equatorial Plasma Bubble(EPB) GNSS receivers’network Indonesia Continuously Operating Reference Station(Ina-CORS) ionospheric map Rate of TEC change index(ROTI)map
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Chaotic Map-Based Authentication and Key Agreement Protocol with Low-Latency for Metasystem
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作者 Guojun Wang Qi Liu 《Computers, Materials & Continua》 SCIE EI 2024年第3期4471-4488,共18页
With the rapid advancement in exploring perceptual interactions and digital twins,metaverse technology has emerged to transcend the constraints of space-time and reality,facilitating remote AI-based collaboration.In t... With the rapid advancement in exploring perceptual interactions and digital twins,metaverse technology has emerged to transcend the constraints of space-time and reality,facilitating remote AI-based collaboration.In this dynamic metasystem environment,frequent information exchanges necessitate robust security measures,with Authentication and Key Agreement(AKA)serving as the primary line of defense to ensure communication security.However,traditional AKA protocols fall short in meeting the low-latency requirements essential for synchronous interactions within the metaverse.To address this challenge and enable nearly latency-free interactions,a novel low-latency AKA protocol based on chaotic maps is proposed.This protocol not only ensures mutual authentication of entities within the metasystem but also generates secure session keys.The security of these session keys is rigorously validated through formal proofs,formal verification,and informal proofs.When confronted with the Dolev-Yao(DY)threat model,the session keys are formally demonstrated to be secure under the Real-or-Random(ROR)model.The proposed protocol is further validated through simulations conducted using VMware workstation compiled in HLPSL language and C language.The simulation results affirm the protocol’s effectiveness in resisting well-known attacks while achieving the desired low latency for optimal metaverse interactions. 展开更多
关键词 Metasystem authentication and key agreement chaotic map secure communication
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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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Mapping upland crop–rice cropping systems for targeted sustainable intensification in South China
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作者 Bingwen Qiu Linhai Yu +4 位作者 Peng Yang Wenbin Wu Jianfeng Chen Xiaolin Zhu Mingjie Duan 《The Crop Journal》 SCIE CSCD 2024年第2期614-629,共16页
Upland crop-rice cropping systems(UCR)facilitate sustainable agricultural intensification.Accurate UCR cultivation mapping is needed to ensure food security,sustainable water management,and rural revitalization.Howeve... Upland crop-rice cropping systems(UCR)facilitate sustainable agricultural intensification.Accurate UCR cultivation mapping is needed to ensure food security,sustainable water management,and rural revitalization.However,datasets describing cropping systems are limited in spatial coverage and crop types.Mapping UCR is more challenging than crop identification and most existing approaches rely heavily on accurate phenology calendars and representative training samples,which limits its applications over large regions.We describe a novel algorithm(RRSS)for automatic mapping of upland crop-rice cropping systems using Sentinel-1 Synthetic Aperture Radar(SAR)and Sentinel-2 Multispectral Instrument(MSI)data.One indicator,the VV backscatter range,was proposed to discriminate UCR and another two indicators were designed by coupling greenness and pigment indices to further discriminate tobacco or oilseed UCR.The RRSS algorithm was applied to South China characterized by complex smallholder rice cropping systems and diverse topographic conditions.This study developed 10-m UCR maps of a major rice bowl in South China,the Xiang-Gan-Min(XGM)region.The performance of the RRSS algorithm was validated based on 5197 ground-truth reference sites,with an overall accuracy of 91.92%.There were7348 km^(2) areas of UCR,roughly one-half of them located in plains.The UCR was represented mainly by oilseed-UCR and tobacco-UCR,which contributed respectively 69%and 15%of UCR area.UCR patterns accounted for only one-tenth of rice production,which can be tripled by intensification from single rice cropping.Application to complex and fragmented subtropical regions suggested the spatiotemporal robustness of the RRSS algorithm,which could be further applied to generate 10-m UCR datasets for application at national or global scales. 展开更多
关键词 Cropping-pattern mapping Paddy rice Sentinel-1/2 China Sustainable intensification
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心脏磁共振T1 mapping在心肌病的应用及成像技术进展
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作者 邓佳 唐惠芳 +4 位作者 周宏 余莹 杨雯敏 周锦标 田进伟 《中国动脉硬化杂志》 2025年第2期154-162,共9页
随着心脏磁共振成像技术的不断发展,T1 mapping可以无创性、可视化和定量地评估心脏疾病的心肌纤维化、水肿和浸润性。应用T1 mapping评估心肌疾病的局限性和弥漫性心肌纤维化,在疾病的诊断、鉴别、治疗和预后风险评估中发挥了重要的临... 随着心脏磁共振成像技术的不断发展,T1 mapping可以无创性、可视化和定量地评估心脏疾病的心肌纤维化、水肿和浸润性。应用T1 mapping评估心肌疾病的局限性和弥漫性心肌纤维化,在疾病的诊断、鉴别、治疗和预后风险评估中发挥了重要的临床作用。本文旨在全面介绍T1 mapping在心肌病患者中的临床应用,归纳常用的扫描技术及其成像原理。 展开更多
关键词 心脏磁共振 T1 mapping 心肌病
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利用CRISPR/Cas9基因编辑技术构建斑马鱼map3k15敲除品系
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作者 贾淳钰 沈延 +3 位作者 陈罡 郑可 秦岩 李雪梅 《基础医学与临床》 2025年第3期290-297,共8页
目的利用CRISPR/Cas9基因编辑技术构建斑马鱼map3k15敲除纯合品系,为进一步研究map3k15在肾脏疾病方面的作用提供动物模型。方法1)分析map3k15在斑马鱼中的表达模式;2)利用CRISPR/Cas9基因编辑技术构建斑马鱼map3k15敲除纯合品系;3)观察... 目的利用CRISPR/Cas9基因编辑技术构建斑马鱼map3k15敲除纯合品系,为进一步研究map3k15在肾脏疾病方面的作用提供动物模型。方法1)分析map3k15在斑马鱼中的表达模式;2)利用CRISPR/Cas9基因编辑技术构建斑马鱼map3k15敲除纯合品系;3)观察map3k15缺失对斑马鱼表型的影响。结果1)map3k15在斑马鱼前肾中表达,且MAP3K15/Map3k15蛋白在多物种间具有高度保守性;2)成功构建了斑马鱼map3k15-/-突变体,并保留+2 bp及+1 bp 2种突变品系;3)map3k15突变斑马鱼在胚胎发育过程中出现卵黄囊、心包及头部的水肿,且随发育时间延长,症状逐渐加重。结论成功构建了map3k15敲除的纯合斑马鱼品系,为未来研究map3k15在肾脏发育及疾病中的作用提供了重要的模型。 展开更多
关键词 map3k15 CRISPR/Cas9基因编辑技术 斑马鱼 肾脏发育
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Fine mapping of Pm71,a novel powdery mildew resistance gene from emmer wheat 被引量:2
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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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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
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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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MAP原则指导下实现考研英语线上虚拟课堂教学的研究
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作者 宁红曼 王晔 《通讯世界》 2025年第1期56-58,共3页
多模态苹果派(multimodal APPLE PIE, MAP)基于多模态教学原则以及交互性教学原则,在教学过程中以有效性、互动性和参与性为核心,对解决当前考研英语教学中存在的问题具有重要指导意义。因此,探究考研英语教学现状,提出MAP原则指导下实... 多模态苹果派(multimodal APPLE PIE, MAP)基于多模态教学原则以及交互性教学原则,在教学过程中以有效性、互动性和参与性为核心,对解决当前考研英语教学中存在的问题具有重要指导意义。因此,探究考研英语教学现状,提出MAP原则指导下实现考研英语线上虚拟课堂的教学设计,从课堂导入、课程呈现、学生合作学习、人机互动、课堂互动5个环节探究考研英语线上虚拟课堂的教学过程,以期提高教师的教学质量以及增强学生的学习效果。 展开更多
关键词 map教学设计 考研英语 虚拟课堂 线上教学
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A novel interference suppression scheme applying complex weighted matrix interleaving mapping for UFMC systems
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作者 WANG Yunzhe MA Tianming +1 位作者 JIN Jie WU Zhong 《High Technology Letters》 EI CAS 2024年第4期380-388,共9页
In response to the problem of inter-carrier interference(ICI)and inter-subband interference(IBI)in the received signals of universal filtered multi-carrier(UFMC)systems,a novel interfer-ence suppression design scheme ... In response to the problem of inter-carrier interference(ICI)and inter-subband interference(IBI)in the received signals of universal filtered multi-carrier(UFMC)systems,a novel interfer-ence suppression design scheme applying the method of complex weighted matrix inter-leaving map-ping(CWMIM)is proposed on the basis of the existing suppression scheme of conjugate weighted butterfly interleaving mapping(CWBIM).The proposed scheme performs matrix interleaving map-ping on the transmitted signal,which not only improves the carrier interference ratio(CIR)of the received signal by combining the original IBI and ICI terms,but also further inhibits the probability of burst error in the received signal.Meanwhile,the scheme can further decrease the impact of phase rotation errors in the received signal by increasing the number of rotation factors.Theoretical analysis and simulation results demonstrate that compared with CWBIM-UFMC,the proposed CWMIM-UFMC can obtain more effective ICI and IBI suppression and better system bit error rate(BER)performance with only a little bit increase in computational complexity. 展开更多
关键词 universal filtered multi-carrier(UFMC) inter-carrier interference(ICI) inter-subband interference(IBI) complex weighted matrix interleaving mapping(CWMIM)
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Landslide Susceptibility Mapping Using RBFN-Based Ensemble Machine Learning Models
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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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Simulation of Urban Mobility between Azove and Aplahoue Using a Geographic Information System
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作者 Apollinaire Cyriaque Agbon 《Journal of Geoscience and Environment Protection》 2025年第1期475-494,共20页
People, goods and services’ mobility is increasing in the cities of Azovè and Aplahoué. This research aims at simulating urban mobility between these two cities using the Geographic Information System. The ... People, goods and services’ mobility is increasing in the cities of Azovè and Aplahoué. This research aims at simulating urban mobility between these two cities using the Geographic Information System. The data was collected through individual interviews with 115 people using a questionnaire. GPS was then used to collect the geographical coordinates of existing infrastructure in the two cities. The roads were identified, categorized and mapped using the data available on the IGN’s 1:50,000 Aplahoué topographic sheet. By calculating the frequencies of the responses, we were able to identify the most frequently used roads, factors and purposes of mobility. These frequencies and the coordinates collected were used to categorize the roads and map them using the Graduted symbols tool in Quantities under ArcGis 10.7 software. Population growth, the extension of urban areas, the increase in commercial and service infrastructures, the rehabilitation of certain roads and the transport of farming products, goods and people associated with the Tohoun border between Benin and Togo are the factors driving urban mobility. This research has shown the infrastructures responsible for this mobility and the spatial structuring of these cities. It has also shown the main current and future routes for urban mobility as well as the traffic development hubs. 展开更多
关键词 FORECAST mapPING MOBILITY Trunk Road Aplahoué-Azovè
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Constructing, Mapping, and Analyzing Global Urban Forest Databases Using Hyperlinks: A World of Vast Unevenness and Research Challenges
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作者 Stanley D. Brunn Olena Dronova Mahmuda Sharmin 《Natural Resources》 2025年第1期1-23,共23页
A distinctive feature of scholarly communities today is exploring topics and concepts in interdisciplinary and international contexts. This observation is increasingly apparent and visible in advancing our thinking an... A distinctive feature of scholarly communities today is exploring topics and concepts in interdisciplinary and international contexts. This observation is increasingly apparent and visible in advancing our thinking and policies related to human/environmental worlds at local, regional, and global scales. Maps are an important part of these innovative and ongoing research approaches. In this context, we consider urban forests a topic meriting more attention of scholars studying the geographic and environmental intersections of the natural sciences with the social sciences and humanities. We construct two innovative knowledge bases, one a conceptual framework based on major themes and concepts related to mapping urban forests using key words of the first 100 results of a Google Scholar query and a second using the number of Google Scholar hyperlinks about mapping urban forests in 244 capital cities. We discovered that the constructed world maps reveal vast global unevenness in our knowledge about urban forests in hyperlink numbers and ratios, results that merit further attention by disciplinary, international and interdisciplinary scholarly communities. 展开更多
关键词 Urban Forests Database mapPING Google Scholar HYPERLINKS DISPARITIES Unevenness
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基于改进RTAB-Map算法的爬壁机器人导航研究
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作者 覃超 唐东林 +3 位作者 游东潘 丁超 饶胜 何媛媛 《工程设计学报》 北大核心 2025年第1期32-41,共10页
针对爬壁机器人难以对大型石化装备壁面感知和自动化检测等难题,提出了一种改进RTAB-Map(real-time appearance-based mapping,基于外观的实时建图)算法,通过多传感器数据融合实现爬壁机器人定位、建图与导航。首先,搭建了具有壁面吸附... 针对爬壁机器人难以对大型石化装备壁面感知和自动化检测等难题,提出了一种改进RTAB-Map(real-time appearance-based mapping,基于外观的实时建图)算法,通过多传感器数据融合实现爬壁机器人定位、建图与导航。首先,搭建了具有壁面吸附能力的机器人运动底盘,以保证爬壁机器人在壁面灵活稳定运动;其次,针对爬壁机器人在壁面滑移导致的里程计累计误差问题,采用扩展卡尔曼滤波并融合编码器和惯性测量单元的数据,为建图和导航提供精确的里程计信息;再次,基于RTAB-Map算法对深度相机、激光雷达及里程计的数据进行融合,生成二维栅格和三维点云地图,实现对装备壁面的完整描述,并基于融合数据构建了爬壁机器人导航算法的框架;最后,在装备壁面进行了实验验证。结果表明:采用融合里程计算法,能显著减小航向角误差,航向角平均误差为0.78°,相对轮式里程计规划,航向角误差减少了88.94%;改进RTAB-Map算法提高了爬壁机器人在壁面环境下的建图与感知能力,结合路径规划算法,实现了机器人自主导航。研究结果对爬壁机器人自动化检测技术的研究及应用具有一定的参考意义。 展开更多
关键词 爬壁机器人 RTAB-map(基于外观的实时建图)算法 扩展卡尔曼滤波 多传感器融合 导航
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T2 mapping不同测量方法在甲状腺相关眼病活动性评估中的应用
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作者 信雨晴 潘富强 +2 位作者 王亚磊 袁玉山 张杨 《中国CT和MRI杂志》 2025年第2期71-73,共3页
目的分析T2 mapping不同感兴趣区(ROI)勾画方法在甲状腺相关眼病(TAO)活动分期中的应用价值。方法27例患者的53个眼眶纳入研究,行3.0T MR冠状位T2 mapping扫描,采用临床活动性评分(CAS)进行分期,通过三种勾画方法获得T2HS(在炎症受累最... 目的分析T2 mapping不同感兴趣区(ROI)勾画方法在甲状腺相关眼病(TAO)活动分期中的应用价值。方法27例患者的53个眼眶纳入研究,行3.0T MR冠状位T2 mapping扫描,采用临床活动性评分(CAS)进行分期,通过三种勾画方法获得T2HS(在炎症受累最重眼肌的信号较高区域勾画小的ROI,记为热点)、T2SS(单只眼肌热点层面的均值)及T2SO(单侧眼眶四条眼肌肌腹层面的均值),分析三者与CAS的相关性及其诊断效能。结果活动期T2HS、T2SS和T2SO均高于非活动期。三者均与CAS正相关,T2SO相关性最强(r=0.606,P<0.0001)。ROC曲线显示三者对TAO活动性分期均有一定的诊断效能,虽然结果显示T2SS诊断效能较优,AUC=0.833,截断值94.25ms时判断活动性敏感度为68%,特异度为91%,但Delong检验提示三者差异无统计学意义。结论T2 mapping序列的三种测量方法均可用于TAO的活动性评估,综合分析,T2SS较适合用于分期。 展开更多
关键词 GRAVES眼病 T2 mapping 磁共振成像 感兴趣区 活动性分期 动眼肌
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基于MAP法的线路板重金属铜氨废水处理研究
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作者 黄常亮 《现代工程科技》 2025年第1期77-80,共4页
随着线路板的广泛应用,其在印刷过程中产生的铜氨废水的排放问题日益突出。铜氨废水中氨氮和铜离子对环境的危害较大,为了解决该问题,提出了一种MAP法和折点氯化法相结合的方法。该方法首先向铜氨废水中加入镁盐和磷酸盐,将氨氮转化为MA... 随着线路板的广泛应用,其在印刷过程中产生的铜氨废水的排放问题日益突出。铜氨废水中氨氮和铜离子对环境的危害较大,为了解决该问题,提出了一种MAP法和折点氯化法相结合的方法。该方法首先向铜氨废水中加入镁盐和磷酸盐,将氨氮转化为MAP沉淀,降低铜氨废水中氨氮的浓度,同时可以将MAP回收再利用;然后向剩余浓液中加入过量的NaClO溶液,进一步将溶液中的氨氮浓度降低,随着NaClO溶液的增加,反应液会逐渐呈碱性,而Cu^(2+)在碱性环境中会与OH-生成Cu(OH)_(2)沉淀,进而降低Cu^(2+)的浓度,从而使铜氨废水中的氨氮和Cu2+的浓度均符合《中华人民共和国环境保护法》的排放要求;最后通过纳氏试剂分光光度法和火焰原子吸收光度法检验反应后浓液中氨氮和Cu^(2+)的浓度。经过验证得知,该方法可以显著降低氨氮和Cu^(2+)的浓度。 展开更多
关键词 map 铜氨废水 氨氮回收 线路板 折点氯化法 环保排放标准
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Functional analysis of tomato MAP65 gene family,highlighting SlMAP65-1's role in fruit morphogenesis
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作者 Peiyu Zhang Guoning Zhu +1 位作者 Chunjiao Zhang Hongliang Zhu 《Journal of Integrative Agriculture》 2025年第2期564-574,共11页
The plant growth process is accompanied by dynamic changes in the microtubules,and the rearrangement of microtubules is regulated by diverse microtubule-associated proteins(MAPs).Plant MAP65s have been exhaustively ch... The plant growth process is accompanied by dynamic changes in the microtubules,and the rearrangement of microtubules is regulated by diverse microtubule-associated proteins(MAPs).Plant MAP65s have been exhaustively characterized in some species,but the information about MAP65 family members in tomato(Solanum lycopersicum)is limited.In this study,nine SlMAP65 family genes were identified in the tomato genome.Then a systematic analysis that considered the physio-chemical properties,evolution,conserved motifs,domains,gene structure,and cis-regulatory elements of SlMAP65 family members was conducted.The family member Sl MAP65-1,which had the highest expression,was knocked out by CRISPR/Cas9.The tomato fruit of slmap65-1 loss of function lines showed an elongated morphology,and the data indicated that SlMAP65-1 is involved in fruit morphogenesis at the early fruit development stage.These results provide new insights for fruit morphogenesis-related research and future functional studies of the SlMAP65 family members in tomato. 展开更多
关键词 TOMATO map65 family fruit shape microtubule organization
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磁共振联合T2-mapping对电针治疗腰椎间盘突出症中短期疗效评价的价值分析
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作者 朱薇萍 吕莹 +2 位作者 徐婷 戴德纯 屠建春 《上海针灸杂志》 2025年第3期290-295,共6页
目的通过磁共振(magnetic resonance,MR)常规序列联合T2-mapping观察电针治疗腰椎间盘突出症(lumbar disc herniation,LDH)后有效及无效患者,探讨其在电针治疗LDH中短期疗效评价中的价值。方法随机选择经电针治疗后判定为有效和无效的LD... 目的通过磁共振(magnetic resonance,MR)常规序列联合T2-mapping观察电针治疗腰椎间盘突出症(lumbar disc herniation,LDH)后有效及无效患者,探讨其在电针治疗LDH中短期疗效评价中的价值。方法随机选择经电针治疗后判定为有效和无效的LDH患者各32例,分别设为A组和B组。两组治疗前后分别记录腰椎日本骨科协会(Japanese Orthopaedic Association,JOA)评估治疗分数、Oswestry功能障碍指数(Oswestry disability index,ODI)评分,进行腰椎MR扫描并测量突出椎间盘髓核T2值和突出部分面积。两组均对治疗后JOA改善率及治疗前T2值、突出面积进行相关性分析,并比较治疗后及随访时T2值和突出面积。结果A组治疗前、治疗后及随访时突出椎间盘髓核T2值均明显高于B组(P<0.05);A组治疗1个疗程后突出部分面积明显小于B组(P<0.05)。A组治疗后JOA评分改善率与治疗前突出椎间盘髓核T2值具有中度相关关系(P<0.05),与突出部分面积未见有线性相关关系(P>0.05)。结论通过MR常规序列联合T2-mapping观察突出椎间盘髓核T2值,在电针治疗LDH中短期疗效评价中存在一定的临床价值,其或可为成为LDH保守治疗方案选择的辅助指标之一。 展开更多
关键词 针刺疗法 腰椎间盘突出症 电针 T2-mapping T2值
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Hybrid image encryption scheme based on hyperchaotic map with spherical attractors
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作者 Zhitang Han Yinghong Cao +1 位作者 Santo Banerjee Jun Mou 《Chinese Physics B》 2025年第3期314-322,共9页
Existing chaotic encryption schemes primarily focus on single types of images,making the design of hybrid image encryption schemes more suitable for practical applications.In this paper,a hyperchaotic map with a spher... Existing chaotic encryption schemes primarily focus on single types of images,making the design of hybrid image encryption schemes more suitable for practical applications.In this paper,a hyperchaotic map with a spherical attractor is proposed,which is constructed using spherical coordinates.Dynamical analyses reveal that the hyperchaotic map exhibits global hyperchaos and high complexity,making it capable of generating more complex chaotic sequences suitable for image encryption.A hybrid encryption scheme based on a hyperchaotic map is proposed for two-dimensional(2D)images,three-dimensional(3D)models,and 3D point clouds.Firstly,the pixels of 2D image and the coordinate data of 3D image are fused into a plaintext cube,which is combined with Hash-512 to obtain the initial value of the hyperchaotic map.Chaotic sequences are utilized for cube space internal confusion and dynamic cross-diffusion.The encrypted images demonstrate high information entropy,and the test results show that the encryption scheme effectively protects the images.The proposed hybrid image encryption scheme provides an efficient solution for securing various types of images. 展开更多
关键词 hyperchaotic map spherical attractor global hyperchaos hybrid image encryption
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