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Developing High-Precision Maps for Automated Driving in China:Legal Obstacles and the Way to Overcome Them 被引量:2
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作者 ZHANG Taolue TU Huizhao QIU Wei 《Journal of Shanghai Jiaotong university(Science)》 EI 2021年第5期658-669,共12页
A high-precision map(HPM)is the key infrastructure to realizing the function of automated driving(AD)and ensuring its safety.However,the current laws and regulations on HPMs in China can lead to serious legal complian... A high-precision map(HPM)is the key infrastructure to realizing the function of automated driving(AD)and ensuring its safety.However,the current laws and regulations on HPMs in China can lead to serious legal compliance problems.Thus,proper measures should be taken to remove these barriers.Starting with a complete view of the current legal obstacles to HPMs in China,this study first explains why these legal obstacles exist and the types of legal interests they are trying to protect.It then analyzes whether new technology could be used as an alternative to resolve these concerns.Factors such as national security,AD industry needs,and personal data protection,as well as the flexibility of applying technology,are discussed and analyzed hierarchically for this purpose.This study proposes that China should adhere to national security and AD industry development,pass new technical regulations that redefine the scope of national security regarding geographic information in the field of HPMs,and establish a national platform under the guidance and monitoring of the government to integrate scattered resources and promote the development of HPMs via crowdsourcing.Regarding the legal obstacles with higher technical plasticity,priority should be given to technical solutions such as“available but invisible”technology.Compared with the previous research,this study reveals the current legal barriers in China that have different levels of relevance to national security and different technical plasticity.It also proposes original measures to remove them,such as coordinating national security with the development of the AD industry,reshaping the boundary of national security and industrial interests,and giving priority to technical solutions for legal barriers that have strong technical plasticity. 展开更多
关键词 automated driving(AD) navigation electronic map(NEM) high-precision map(HPM) surveying and mapping national security “available but invisible”technology
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High-precision classification of benthic habitat sediments in shallow waters of islands by multi-source data
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作者 Qiuhua TANG Ningning LI +4 位作者 Yujie ZHANG Zhipeng DONG Yongling ZHENG Jingjing BAO Jingyu ZHANG 《Journal of Oceanology and Limnology》 2026年第1期99-108,共10页
Benthic habitat mapping is an emerging discipline in the international marine field in recent years,providing an effective tool for marine spatial planning,marine ecological management,and decision-making applications... Benthic habitat mapping is an emerging discipline in the international marine field in recent years,providing an effective tool for marine spatial planning,marine ecological management,and decision-making applications.Seabed sediment classification is one of the main contents of seabed habitat mapping.In response to the impact of remote sensing imaging quality and the limitations of acoustic measurement range,where a single data source does not fully reflect the substrate type,we proposed a high-precision seabed habitat sediment classification method that integrates data from multiple sources.Based on WorldView-2 multi-spectral remote sensing image data and multibeam bathymetry data,constructed a random forests(RF)classifier with optimal feature selection.A seabed sediment classification experiment integrating optical remote sensing and acoustic remote sensing data was carried out in the shallow water area of Wuzhizhou Island,Hainan,South China.Different seabed sediment types,such as sand,seagrass,and coral reefs were effectively identified,with an overall classification accuracy of 92%.Experimental results show that RF matrix optimized by fusing multi-source remote sensing data for feature selection were better than the classification results of simple combinations of data sources,which improved the accuracy of seabed sediment classification.Therefore,the method proposed in this paper can be effectively applied to high-precision seabed sediment classification and habitat mapping around islands and reefs. 展开更多
关键词 Wuzhizhou Island marine remote sensing coastal mapping multi-spectral remote sensing shallow water reef seabed sediment classification benthic habitat mapping multi-source data fusion random forest(RF)
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Data Logic Structure and Key Technologies on Intelligent High-precision Map 被引量:17
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作者 Jingnan LIU Jiao ZHAN +2 位作者 Chi GUO Tingting LEI Ying LI 《Journal of Geodesy and Geoinformation Science》 2020年第3期1-17,共17页
Taking autonomous driving and driverless as the research object,we discuss and define intelligent high-precision map.Intelligent high-precision map is considered as a key link of future travel,a carrier of real-time p... Taking autonomous driving and driverless as the research object,we discuss and define intelligent high-precision map.Intelligent high-precision map is considered as a key link of future travel,a carrier of real-time perception of traffic resources in the entire space-time range,and the criterion for the operation and control of the whole process of the vehicle.As a new form of map,it has distinctive features in terms of cartography theory and application requirements compared with traditional navigation electronic maps.Thus,it is necessary to analyze and discuss its key features and problems to promote the development of research and application of intelligent high-precision map.Accordingly,we propose an information transmission model based on the cartography theory and combine the wheeled robot’s control flow in practical application.Next,we put forward the data logic structure of intelligent high-precision map,and analyze its application in autonomous driving.Then,we summarize the computing mode of“Crowdsourcing+Edge-Cloud Collaborative Computing”,and carry out key technical analysis on how to improve the quality of crowdsourced data.We also analyze the effective application scenarios of intelligent high-precision map in the future.Finally,we present some thoughts and suggestions for the future development of this field. 展开更多
关键词 intelligent high-precision map information transmission model data logic structure user model computing mode edge-cloud collaboration
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基于Connectivity Map的药物重定位评价维拉帕米作为治疗帕金森病的药物
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作者 新吉乐 刘晶 +6 位作者 张欣翼 郭家缘 韩文卓 孙怡馨 赵乐 冯卫生 郑晓珂 《中国临床药理学与治疗学》 北大核心 2026年第1期14-27,共14页
目的:筛选调控帕金森病(Parkinson's disease,PD)发病关键基因及相关转录因子表达的小分子化合物。方法:分析PD患者的基因表达谱数据,筛选PD发病关键基因及转录因子。Connectivity Map(CMap)筛选可调控转录因子表达的小分子药物,并... 目的:筛选调控帕金森病(Parkinson's disease,PD)发病关键基因及相关转录因子表达的小分子化合物。方法:分析PD患者的基因表达谱数据,筛选PD发病关键基因及转录因子。Connectivity Map(CMap)筛选可调控转录因子表达的小分子药物,并在6-羟基多巴胺(6-OHDA)诱导损伤的PC12细胞和PD小鼠模型评价其PD治疗作用。结果:维拉帕米(verapamil,Ver)为潜在的候选药物。Ver对6-OHDA损伤的PC12细胞具有保护作用,同时对6-OHDA诱导的PAX5、LEF1、MTF1、IKZF3和SP140等转录因子,以及ITGA6、CDH1、CD40、ESR1、SMAD3、CXCR4等PD发病基因的表达具有调控作用。PD模型小鼠中,Ver可对α-突触核蛋白(α-Syn)表达有一定抑制作用,但对上述PD发病基因及其转录因子和调控作用较弱。结论:Ver对PD的治疗作用部分依赖于对PD发病基因及其相关转录因子的调控作用。 展开更多
关键词 帕金森病 转录因子 Connectivity map 维拉帕米 6-羟基多巴胺
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Native T1 mapping值显著延长心脏纤维瘤一例
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作者 文涛 张辉 +3 位作者 甘铁军 胡万均 李世兰 张静 《磁共振成像》 北大核心 2026年第1期120-122,共3页
本研究为回顾性研究,遵守《赫尔辛基宣言》,并经兰州大学第二医院伦理委员会审核批准,免除受试者知情同意,批准文号:2025A-547。患儿,女,2月8天,因“发现心脏肿瘤2月”于2024年11月就诊于我院,患儿于2个月前出生后外院检查提示左心室肿... 本研究为回顾性研究,遵守《赫尔辛基宣言》,并经兰州大学第二医院伦理委员会审核批准,免除受试者知情同意,批准文号:2025A-547。患儿,女,2月8天,因“发现心脏肿瘤2月”于2024年11月就诊于我院,患儿于2个月前出生后外院检查提示左心室肿瘤,未予特殊诊治,现为进一步明确诊治收住我院心脏外科。患儿足月(38+6周)、顺产、无心脏肿瘤家族史。查体:心前区无隆起,心界不大,心音有力、律齐,胸骨左缘第2~3肋间可闻及3/6及吹风样杂音,静息血氧饱和度100%。 展开更多
关键词 心脏肿瘤 心脏纤维瘤 多模态磁共振成像 心脏磁共振 Native T1 mapping
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T2 Mapping联合DWI序列评估直肠癌脉管侵犯价值研究
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作者 李茜玮 陈安良 +2 位作者 王楠 林良杰 刘爱连 《中国CT和MRI杂志》 2026年第1期149-152,共4页
目的探讨T2 mapping与DWI序列预测直肠癌脉管侵犯的价值。方法回顾性分析经本院行3.0T MRI扫描且经术后病理证实的直肠癌脉管侵犯13例,脉管非侵犯20例,2名观察者分别于瘤体显示最大层面参考增强动脉期图像及DWI图像于T2 mapping及ADC图... 目的探讨T2 mapping与DWI序列预测直肠癌脉管侵犯的价值。方法回顾性分析经本院行3.0T MRI扫描且经术后病理证实的直肠癌脉管侵犯13例,脉管非侵犯20例,2名观察者分别于瘤体显示最大层面参考增强动脉期图像及DWI图像于T2 mapping及ADC图像上测量病灶T2值及ADC值。采用组内相关系数(intraclass correlation cofficient,ICC)评估两名观察者测量参数值的一致性。采用独立样本t检验或Mann-Whitney U检验分析两组病例各参数的差异。采用Logistic回归计算有统计学差异的参数联合评估直肠癌LVI的预测值。采用ROC曲线评估有差异参数单独或联合的诊断效能,并利用De-Long检验比较各ROC曲线间的差异。采用Pearson相关性检验分析两参数值的相关性。结果2名观察者测量T2值及ADC值一致性好(ICC>0.75)。脉管侵犯组的T2值及ADC值低于非脉管侵犯组(77.15±6.95ms、0.69±0.15mm^(2)/s vs 87.04±7.75ms、0.90±0.21 mm^(2)/s,P<0.05)。ADC值与ADC-T2联合鉴别两组疾病的AUC值比较差异具有统计学意义(P=0.036)。结论T2 mapping和DWI序列可预测直肠癌脉管侵犯,两序列联合效能提升,因此T2值与ADC值联合可为临床诊疗直肠癌脉管侵犯提供参考信息。 展开更多
关键词 直肠癌 脉管侵犯 磁共振成像 T2 mapping成像 弥散加权成像
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Exploring the Effects of Background Image Complexity and Map Symbol Load on the Usability of Image-maps 被引量:1
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作者 PENG Qian XIA Yuxin QIU Zeren 《Journal of Geodesy and Geoinformation Science》 2025年第2期5-20,共16页
Image-maps,a hybrid design with satellite images as background and map symbols uploaded,aim to combine the advantages of maps’high interpretation efficiency and satellite images’realism.The usability of image-maps i... Image-maps,a hybrid design with satellite images as background and map symbols uploaded,aim to combine the advantages of maps’high interpretation efficiency and satellite images’realism.The usability of image-maps is influenced by the representations of background images and map symbols.Many researchers explored the optimizations for background images and symbolization techniques for symbols to reduce the complexity of image-maps and improve the usability.However,little literature was found for the optimum amount of symbol loading.This study focuses on the effects of background image complexity and map symbol load on the usability(i.e.,effectiveness and efficiency)of image-maps.Experiments were conducted by user studies via eye-tracking equipment and an online questionnaire survey.Experimental data sets included image-maps with ten levels of map symbol load in ten areas.Forty volunteers took part in the target searching experiments.It has been found that the usability,i.e.,average time viewed(efficiency)and average revisits(effectiveness)of targets recorded,is influenced by the complexity of background images,a peak exists for optimum symbol load for an image-map.The optimum levels for symbol load for different image-maps also have a peak when the complexity of the background image/image map increases.The complexity of background images serves as a guideline for optimum map symbol load in image-map design.This study enhanced user experience by optimizing visual clarity and managing cognitive load.Understanding how these factors interact can help create adaptive maps that maintain clarity and usability,guiding AI algorithms to adjust symbol density based on user context.This research establishes the practices for map design,making cartographic tools more innovative and more user-centric. 展开更多
关键词 remote sensing image map point label complexity
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A Deep-Learning-Based Method for Interpreting Distribution and Difference Knowledge from Raster Topographic Maps 被引量:1
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作者 PAN Yalan TI Peng +1 位作者 LI Mingyao LI Zhilin 《Journal of Geodesy and Geoinformation Science》 2025年第2期21-36,共16页
Topographic maps,as essential tools and sources of information for geographic research,contain precise spatial locations and rich map features,and they illustrate spatio-temporal information on the distribution and di... Topographic maps,as essential tools and sources of information for geographic research,contain precise spatial locations and rich map features,and they illustrate spatio-temporal information on the distribution and differences of various surface features.Currently,topographic maps are mainly stored in raster and vector formats.Extraction of the spatio-temporal knowledge in the maps—such as spatial distribution patterns,feature relationships,and dynamic evolution—still primarily relies on manual interpretation.However,manual interpretation is time-consuming and laborious,especially for large-scale,long-term map knowledge extraction and application.With the development of artificial intelligence technology,it is possible to improve the automation level of map knowledge interpretation.Therefore,the present study proposes an automatic interpretation method for raster topographic map knowledge based on deep learning.To address the limitations of current data-driven intelligent technology in learning map spatial relations and cognitive logic,we establish a formal description of map knowledge by mapping the relationship between map knowledge and features,thereby ensuring interpretation accuracy.Subsequently,deep learning techniques are employed to extract map features automatically,and the spatio-temporal knowledge is constructed by combining formal descriptions of geographic feature knowledge.Validation experiments demonstrate that the proposed method effectively achieves automatic interpretation of spatio-temporal knowledge of geographic features in maps,with an accuracy exceeding 80%.The findings of the present study contribute to machine understanding of spatio-temporal differences in map knowledge and advances the intelligent interpretation and utilization of cartographic information. 展开更多
关键词 raster topographic maps geographic feature knowledge intelligent interpretation deep learning
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基于素养导向理念的大学生MAPS体育教学策略创新研究
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作者 秦永 《体育科技》 2025年第2期104-106,共3页
《关于强化学校体育促进学生身心健康全面发展的意见》明确将提高学生的体育素养上升至国家层面。素养导向下的体育教学旨在培养个体具备动机、信心、身体能力、知识和理解力,致力于将有目的的身体活动应用在日常生活之中。通过对相关... 《关于强化学校体育促进学生身心健康全面发展的意见》明确将提高学生的体育素养上升至国家层面。素养导向下的体育教学旨在培养个体具备动机、信心、身体能力、知识和理解力,致力于将有目的的身体活动应用在日常生活之中。通过对相关理论与文献探讨,提出素养导向下大学生体育课堂教学的重点,以逻辑分析法深入剖析MAPS教学法所囊括的心智绘图、提问策略、口头发表和同侪鹰架四个教学策略,佐以大学生竞争型阵地攻守的篮球教学设计为例,希冀为深化改革高校公共体育课程和实施素养导向体育教学规划提供参考。研究发现,首先,将MAPS教学法融入到以素养为导向的大学生体育选项的技战术课程,能够有效地协助学生在战术与策略运用方面进行具体分析,透过心智绘图比较与其他组别的优劣势,找到应对方法;其次,通过教师引导提问,让学生更加清晰战术策略,以同侪发问讨论的形式对本组成果进行口头汇报;最后,以分组角色且委派不同学习任务,以达到提升学生身体素养所具备的认知、理解与运动技能,进而提高学生同侪鹰架的学习动机与成效。研究建议:(1)教师在建立概念与分析技战术策略时,秉承素养导向的理念,选用MAPS教学法,可有效帮助学生达成教学大纲的体育素养的翻转学习,迈向全人教育发展之路;(2)教学革新或课程改革应采用更为严谨的实证性教学实验研究,以构建出多元化、多项目群的身体素养导向的MAPS教学模式。 展开更多
关键词 身体素养 maps教学法 体育教学 课程设计
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Research on Integrated Circuit Talent Stability Construction Based on Turnover Attribution in High-Precision, Specialized, and Innovative Enterprises
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作者 Mingjie Cheng Ziying Chen +1 位作者 Xiayuan Huang Zhixin Jian 《Proceedings of Business and Economic Studies》 2025年第5期87-94,共8页
With the intensifying competition in the integrated circuit(IC)industry,the high turnover rate of integrated circuit engineers has become a prominent issue affecting the technological continuity of high-precision,spec... With the intensifying competition in the integrated circuit(IC)industry,the high turnover rate of integrated circuit engineers has become a prominent issue affecting the technological continuity of high-precision,specialized,and innovative enterprises.As a representative of such enterprises,JL Technology has faced challenges to its R&D efficiency due to talent loss in recent years.This study takes this enterprise as a case to explore feasible paths to reduce turnover rates through optimizing training and career development systems.The research designs a method combining learning maps and talent maps,utilizes a competency model to clarify the direction for engineers’skill improvement,implements talent classification management using a nine-grid model,and achieves personalized training through Individual Development Plans(IDPs).Analysis of the enterprise’s historical data reveals that the main reasons for turnover are unclear career development paths and insufficient resources for skill improvement.After pilot implementation,the turnover rate in core departments decreased by 12%,and employee satisfaction with training increased by 24%.The results indicate that matching systematic talent reviews with dynamic learning resources can effectively enhance engineers’sense of belonging.This study provides a set of highly operational management tools for small and medium-sized high-precision,specialized,and innovative technology enterprises,verifies their applicability in such enterprises,and offers replicable experiences for similar enterprises to optimize their talent strategies[1]. 展开更多
关键词 high-precision specialized and innovative enterprises IC engineers Learning map Talent review Talent map
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Microstructure Homogenization Control of GH4706 Alloy by Hot Deformation Maps
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作者 Zheng Deyu Xia Yufeng Zhou Jie 《稀有金属材料与工程》 北大核心 2025年第12期3000-3009,共10页
Hot compression tests for GH4706 alloy were performed at a true strain of 1.2 within the temperature range of 950-1150℃ and the strain rate range of 0.001-1 s^(-1).The optimal hot deformation temperature and strain r... Hot compression tests for GH4706 alloy were performed at a true strain of 1.2 within the temperature range of 950-1150℃ and the strain rate range of 0.001-1 s^(-1).The optimal hot deformation temperature and strain rate range were determined using nephogram maps of dynamic recrystallization fraction,average grain size,and grain distribution standard deviation.Processing maps at true strains from 0.4 to 0.9 were generated based on flow stress curves to identify the strain corresponding to optimal microstructure homogenization efficiency at various temperatures and strain rates.Results show that within the optimal parameter range,under the conditions of 1150℃ and 0.01 s^(-1),the true strain of about 0.6 results in the optimal microstructure homogenization efficiency.The grain orientation spread maps obtained from the experiment also confirms this conclusion.This study provides an effective method for microstructure homogenization control of GH4706 alloy and an effective reference for the minimum strain threshold of the local part of the forging in engineering. 展开更多
关键词 GH4706 alloy dynamic recrystallization MICROSTRUCTURE homogenization efficiency processing map
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Recent progress on high-precision construction of nanoarchitectured SERS substrates for ultrasensitive bio-medical sensors
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作者 Heguang Liu Ben Mou +8 位作者 Jinxin Li Na Tian Yiming Feng Xiaodong Cui Yury Kapitonov Huageng Liang Caiyin You Yuan Li Tianyou Zhai 《Advanced Powder Materials》 2025年第4期30-57,共28页
Surface-enhanced Raman spectroscopy(SERS)has evolved from a laboratory technique to a practical tool for ultra-sensitive detection,particularly in the biomedical field,where precise molecular identification is crucial... Surface-enhanced Raman spectroscopy(SERS)has evolved from a laboratory technique to a practical tool for ultra-sensitive detection,particularly in the biomedical field,where precise molecular identification is crucial.Despite significant advancements,a gap remains in the literature,as no comprehensive review systematically addresses the high-precision construction of SERS substrates for ultrasensitive biomedical detection.This review fills that gap by exploring recent progress in fabricating high-precision SERS substrates,emphasizing their role in enabling ultrasensitive bio-medical sensors.We carefully examine the key to these advancements is the precision engineering of substrates,including noble metals,semiconductors,carbon-based materials,and two-dimensional materials,which is essential for achieving the high sensitivity required for ultrasensitive detection.Applications in biomedical diagnostics and molecular analysis are highlighted.Finally,we address the challenges in SERS substrate preparation and outline future directions,focusing on improvement strategies,design concepts,and expanding applications for these advanced materials. 展开更多
关键词 SERS SERS substrates high-precision construction Ultrasensitive bio-medical sensors Enhancement mechanism
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基于Self-Organizing Maps回归算法的黄河流域降水量空间预测研究
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作者 刘文婷 白明照 李凤云 《陕西水利》 2025年第6期9-11,16,共4页
基于Self-Organizing Maps(SOM)回归算法,构建黄河流域降水量空间预测模型。利用2020年305个气象站点降水观测数据,结合海拔、坡度、坡向、NDVI等地理环境因子,通过网格搜索法优化SOM模型参数。结果表明,SOM模型成功捕捉了黄河流域降水... 基于Self-Organizing Maps(SOM)回归算法,构建黄河流域降水量空间预测模型。利用2020年305个气象站点降水观测数据,结合海拔、坡度、坡向、NDVI等地理环境因子,通过网格搜索法优化SOM模型参数。结果表明,SOM模型成功捕捉了黄河流域降水量空间异质性,预测精度较高(R2=0.83,RMSE=47.6 mm)。降水量呈现由东南向西北递减趋势,范围在135 mm~1171 mm之间,高值区(>900 mm)主要分布在东南部,中值区(500 mm~800 mm)位中部,低值区(<400 mm)集中在西北部。该研究可为降水量空间预测提供一种有效的新途径。 展开更多
关键词 Self-Organizing maps 降水量 黄河流域 空间预测
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High-precision large-aperture single-frame interferometric surface profile measurement method based on deep learning
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作者 Liang Tang Mingzhi Han +3 位作者 Shuai Yang Ye Sun Lirong Qiu Weiqian Zhao 《International Journal of Extreme Manufacturing》 2025年第5期481-492,共12页
Large-aperture optical components are of paramount importance in domains such as integrated circuits,photolithography,aerospace,and inertial confinement fusion.However,measuring their surface profiles relies predomina... Large-aperture optical components are of paramount importance in domains such as integrated circuits,photolithography,aerospace,and inertial confinement fusion.However,measuring their surface profiles relies predominantly on the phase-shifting approach,which involves collecting multiple interferograms and imposes stringent demands on environmental stability.These issues significantly hinder its ability to achieve real-time and dynamic high-precision measurements.Therefore,this study proposes a high-precision large-aperture single-frame interferometric surface profile measurement(LA-SFISPM)method based on deep learning and explores its capability to realize dynamic measurements with high accuracy.The interferogram is matched to the phase by training the data measured using the small aperture.The consistency of the surface features of the small and large apertures is enhanced via contrast learning and feature-distribution alignment.Hence,high-precision phase reconstruction of large-aperture optical components can be achieved without using a phase shifter.The experimental results show that for the tested mirror withΦ=820 mm,the surface profile obtained from LA-SFISPM is subtracted point-by-point from the ground truth,resulting in a maximum single-point error of 4.56 nm.Meanwhile,the peak-to-valley(PV)value is 0.0758λ,and the simple repeatability of root mean square(SR-RMS)value is 0.00025λ,which aligns well with the measured results obtained by ZYGO.In particular,a significant reduction in the measurement time(reduced by a factor of 48)is achieved compared with that of the traditional phase-shifting method.Our proposed method provides an efficient,rapid,and accurate method for obtaining the surface profiles of optical components with different diameters without employing a phase-shifting approach,which is highly desired in large-aperture interferometric measurement systems. 展开更多
关键词 large-aperture optical components single-frame interferometric surface profile deep learning dynamic high-precision measurement
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Single Qubit Quantum Logistic-Sine XYZ-Rotation Maps:An Ultra-Wide Range Dynamics for Image Encryption
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作者 De Rosal Ignatius Moses Setiadi T.Sutojo +4 位作者 Supriadi Rustad Muhamad Akrom Sudipta Kr Ghosal Minh T.Nguyen Arnold Adimabua Ojugo 《Computers, Materials & Continua》 2025年第5期2161-2188,共28页
Data security has become a growing priority due to the increasing frequency of cyber-attacks,necessitating the development of more advanced encryption algorithms.This paper introduces Single Qubit Quantum Logistic-Sin... Data security has become a growing priority due to the increasing frequency of cyber-attacks,necessitating the development of more advanced encryption algorithms.This paper introduces Single Qubit Quantum Logistic-Sine XYZ-Rotation Maps(SQQLSR),a quantum-based chaos map designed to generate one-dimensional chaotic sequences with an ultra-wide parameter range.The proposed model leverages quantum superposition using Hadamard gates and quantum rotations along the X,Y,and Z axes to enhance randomness.Extensive numerical experiments validate the effectiveness of SQQLSR.The proposed method achieves a maximum Lyapunov exponent(LE)of≈55.265,surpassing traditional chaotic maps in unpredictability.The bifurcation analysis confirms a uniform chaotic distribution,eliminating periodic windows and ensuring higher randomness.The system also generates an expanded key space exceeding 10^(40),enhancing security against brute-force attacks.Additionally,SQQLSR is applied to image encryption using a simple three-layer encryption scheme combining permutation and substitution techniques.This approach is intentionally designed to highlight the impact of SQQLSR-generated chaotic sequences rather than relying on a complex encryption algorithm.Theencryption method achieves an average entropy of 7.9994,NPCR above 99.6%,and UACI within 32.8%–33.8%,confirming its strong randomness and sensitivity to minor modifications.The robustness tests against noise,cropping,and JPEG compression demonstrate its resistance to statistical and differential attacks.Additionally,the decryption process ensures perfect image reconstruction with an infinite PSNR value,proving the algorithm’s reliability.These results highlight SQQLSR’s potential as a lightweight yet highly secure encryption mechanism suitable for quantum cryptography and secure communications. 展开更多
关键词 Single qubit quantumchaotic quantumchaotic map quantumimage encryption quantumlogistic map quantum sine map
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An efficient and high-precision algorithm for solving multiple deformation modes of elastic beams
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作者 Yunzhou WANG Binbin ZHENG +2 位作者 Lingling HU Nan SUN Minghui FU 《Applied Mathematics and Mechanics(English Edition)》 2025年第9期1753-1770,共18页
The elliptic integral method(EIM) is an efficient analytical approach for analyzing large deformations of elastic beams. However, it faces the following challenges.First, the existing EIM can only handle cases with kn... The elliptic integral method(EIM) is an efficient analytical approach for analyzing large deformations of elastic beams. However, it faces the following challenges.First, the existing EIM can only handle cases with known deformation modes. Second,the existing EIM is only applicable to Euler beams, and there is no EIM available for higher-precision Timoshenko and Reissner beams in cases where both force and moment are applied at the end. This paper proposes a general EIM for Reissner beams under arbitrary boundary conditions. On this basis, an analytical equation for determining the sign of the elliptic integral is provided. Based on the equation, we discover a class of elliptic integral piecewise points that are distinct from inflection points. More importantly, we propose an algorithm that automatically calculates the number of inflection points and other piecewise points during the nonlinear solution process, which is crucial for beams with unknown or changing deformation modes. 展开更多
关键词 elastic beam elliptic integral deformation mode transition equilibrium path high-precision algorithm
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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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Comparing disaggregation approaches DSMART and PPD in disaggregating soil series maps
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作者 Tahmid Huq EASHER Daniel SAURETTE +3 位作者 Brandon HEUNG Adam GILLESPIE Richard J.HECK Asim BISWAS 《Pedosphere》 2025年第2期387-404,共18页
Conventional soil maps(CSMs)often have multiple soil types within a single polygon,which hinders the ability of machine learning to accurately predict soils.Soil disaggregation approaches are commonly used to improve ... Conventional soil maps(CSMs)often have multiple soil types within a single polygon,which hinders the ability of machine learning to accurately predict soils.Soil disaggregation approaches are commonly used to improve the spatial and attribute precision of CSMs.The approach disaggregation and harmonization of soil map units through resampled classification trees(DSMART)is popular but computationally intensive,as it generates and assigns synthetic samples to soil series based on the areal coverage information of CSMs.Alternatively,the disaggregation approach pure polygon disaggregation(PPD)assigns soil series based solely on the proportions of soil series in pure polygons in CSMs.This study compared these two disaggregation approaches by applying them to a CSM of Middlesex County,Ontario,Canada.Four different sampling methods were used:two sampling designs,simple random sampling(SRS)and conditional Latin hypercube sampling(cLHS),with two sample sizes(83100 and 19420 samples per sampling plan),both based on an area-weighted approach.Two machine learning algorithms(MLAs),C5.0 decision tree(C5.0)and random forest(RF),were applied to the disaggregation approaches to compare the disaggregation accuracy.The accuracy assessment utilized a set of 500 validation points obtained from the Middlesex County soil survey report.The MLA C5.0(Kappa index=0.58–0.63)showed better performance than RF(Kappa index=0.53–0.54)based on the larger sample size,and PPD with C5.0 based on the larger sample size was the best-performing(Kappa index=0.63)approach.Based on the smaller sample size,both cLHS(Kappa index=0.41–0.48)and SRS(Kappa index=0.40–0.47)produced similar accuracy results.The disaggregation approach PPD exhibited lower processing capacity and time demands(1.62–5.93 h)while yielding maps with lower uncertainty as compared to DSMART(2.75–194.2 h).For CSMs predominantly composed of pure polygons,utilizing PPD for soil series disaggregation is a more efficient and rational choice.However,DSMART is the preferable approach for disaggregating soil series that lack pure polygon representations in the CSMs. 展开更多
关键词 conditioned Latin hypercube sampling conventional soil map machine learning algorithm processing capacity and time sample size simple random sampling soil map unit soil series disaggregation
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Channel Knowledge Maps for 6G Wireless Networks:Construction,Applications,and Future Challenges
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作者 LIU Xingchen SUN Shu +2 位作者 TAO Meixia Aryan KAUSHIK YAN Hangsong 《ZTE Communications》 2025年第2期46-59,共14页
The advent of 6G wireless networks promises unprecedented connectivity,supporting ultra-high data rates,low latency,and massive device connectivity.However,these ambitious goals introduce significant challenges,partic... The advent of 6G wireless networks promises unprecedented connectivity,supporting ultra-high data rates,low latency,and massive device connectivity.However,these ambitious goals introduce significant challenges,particularly in channel estimation due to complex and dynamic propagation environments.This paper explores the concept of channel knowledge maps(CKMs)as a solution to these challenges.CKMs enable environment-aware communications by providing location-specific channel information,reducing reliance on real-time pilot measurements.We categorize CKM construction techniques into measurement-based,model-based,and hybrid methods,and examine their key applications in integrated sensing and communication(ISAC)systems,beamforming,trajectory optimization of unmanned aerial vehicles(UAVs),base station(BS)placement,and resource allocation.Furthermore,we discuss open challenges and propose future research directions to enhance the robustness,accuracy,and scalability of CKM-based systems in the evolving 6G landscape. 展开更多
关键词 channel knowledge map channel modeling wireless communication 6G
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