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Early Postnatal Pharmacological Intervention Rescues the Disruption of Developmental Connectivity in MAO-A KO Mice
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作者 Qian Xue Hanpeng Xu +6 位作者 Muye Zhu Bin Qian Lei Gao Lin Gou Houri Hintiryan Jean C.Shih Hong-Wei Dong 《Neuroscience Bulletin》 2025年第2期339-343,共5页
Dear Editors,The term“developmental disconnection syndromes”(DDSs)was first coined by Geshwind and Levitt in 2007[1]to describe the weakening of already formed connections or an absence of certain connections to est... Dear Editors,The term“developmental disconnection syndromes”(DDSs)was first coined by Geshwind and Levitt in 2007[1]to describe the weakening of already formed connections or an absence of certain connections to establish correct organization de novo in early developmental stages.DDSs include a number of neuropsychiatric diseases,such as autistic spectrum disorder(ASD)[1,2],which is characterized by impaired social communication and repetitive and stereotyped behaviors.Nevertheless,the exact etiology underlying these“disconnections”and their abnormal developmental trajectory remains largely unclear.Even less known is whether developmental disconnections relevant to autism can be rescued by early intervention thereby preventing neuropsychiatric and repetitive symptoms in later stages.This study addresses these important questions. 展开更多
关键词 impaired social communication Developmental Disconnection Syndromes Neuropsychiatric Diseases Early Postnatal disconnection syndromes ddss Pharmacological Intervention MAOA KO Mice weakening already formed connections
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基于H1 Connect的多元化评价标签相关分析及综合评价指标体系建立研究 被引量:1
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作者 许丹 罗祥东 +1 位作者 王雯霞 徐爽 《江苏科技信息》 2025年第5期93-98,共6页
文章基于H1 Connect对生物医学科技论文各类同行评议标签进行相关性分析研究,结合多元化指标尝试构建更为全面、科学的论文评价指标体系。从H1 Connect、Altmetric、WoS(Web of Science)平台获取同行评议、社会影响力、学术影响力代表... 文章基于H1 Connect对生物医学科技论文各类同行评议标签进行相关性分析研究,结合多元化指标尝试构建更为全面、科学的论文评价指标体系。从H1 Connect、Altmetric、WoS(Web of Science)平台获取同行评议、社会影响力、学术影响力代表性指标和评价标签,根据规则计算出综合评分,运用SPSS软件进行斯皮尔曼相关性比较分析。H1 Connect中同行评议各指标与不同评价标签之间大多呈低相关或不相关关系。相对引用率与同行评级之间也呈低相关或不相关关系,而星级权重与同行评级“Very Good”和“Exceptional”呈中度相关。文章提出综合评分指标CS,该指标与同行评议结果呈中度相关性,与社会影响力和学术影响力评价结果也高度一致,可为生物医学领域的学术评价提供新视角。 展开更多
关键词 H1 connect 综合评分 评价标签 对比分析
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基于改进RRT-Connect与DWA融合的移动机器人路径规划
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作者 罗毅 邓嘉 《系统仿真学报》 北大核心 2025年第10期2545-2556,共12页
为提高复杂环境中移动机器人动态路径规划效率和质量,提出了一种改进RRT-connect与DWA融合的路径规划算法。引入两棵扩展随机树交替扩展,设置动态限制采样区域,降低采样过程随机性并保证算法的概率完备性,采用目标偏向自适应步长策略,... 为提高复杂环境中移动机器人动态路径规划效率和质量,提出了一种改进RRT-connect与DWA融合的路径规划算法。引入两棵扩展随机树交替扩展,设置动态限制采样区域,降低采样过程随机性并保证算法的概率完备性,采用目标偏向自适应步长策略,以增强随机树扩展过程的目标导向性;采用贪心策略裁剪路径冗余节点并对全局路径进行平滑处理,得到全局优化路径;利用DWA跟踪全局路径,对评价函数进行改进,引入路径跟踪评价函数并采用自适应权重策略,同时引入路径校正机制,去除无效局部目标点,避免回绕现象。仿真结果表明:相比改进前,所提算法在不同静态环境中的运行时间分别下降36.18%、68.61%和89.33%,路径长度缩短17.61%、17.48%和12.33%,在动态环境中运行时间下降31.46%,路径长度缩短9.21%,并始终保证了路径的安全性。 展开更多
关键词 移动机器人 自适应 RRT-connect 动态采样区域 DWA 路径规划
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Evaluation of dynamic inter-well connectivity by using the state-variable-capacitance model
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作者 Li-Wen Guo Shi-Yuan Qu +2 位作者 Yuan-Yuan Lei Zhi-Hong Kang Shuo-Liang Wang 《Petroleum Science》 2025年第8期3380-3396,共17页
During oilfield development,a comprehensive model for assessing inter-well connectivity and connected volume within reservoirs is crucial.Traditional capacitance(TC)models,widely used in inter-well data analysis,face ... During oilfield development,a comprehensive model for assessing inter-well connectivity and connected volume within reservoirs is crucial.Traditional capacitance(TC)models,widely used in inter-well data analysis,face challenges when dealing with rapidly changing reservoir conditions over time.Additionally,TC models struggle with complex,random noise primarily caused by measurement errors in production and injection rates.To address these challenges,this study introduces a dynamic capacitance(SV-DC)model based on state variables.By integrating the extended Kalman filter(EKF)algorithm,the SV-DC model provides more flexible predictions of inter-well connectivity and time-lag efficiency compared to the TC model.The robustness of the SV-DC model is verified by comparing relative errors between preset and calculated values through Monte Carlo simulations.Sensitivity analysis was performed to compare the model performance with the benchmark,using the Qinhuangdao Oilfield as a case study.The results show that the SV-DC model accurately predicts water breakthrough times.Increases in the liquid production index and water cut in two typical wells indicate the development time of ineffective circulation channels,further confirming the accuracy and reliability of the model.The SV-DC model offers significant advantages in addressing complex,dynamic oilfield production scenarios and serves as a valuable tool for the efficient and precise planning and management of future oilfield developments. 展开更多
关键词 Capacitance model Inter-well connectivity Time-lag coefficient connected volume Reservoir simulation
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Overview of Prefabricated Segmental Pier Column Connection Technology
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作者 MaoGuang Yue Pan Huang 《Journal of Environmental & Earth Sciences》 2025年第4期309-323,共15页
With the acceleration of urbanization,prefabricated bridges have become a significant choice for transportation infrastructure construction due to their environmental friendliness,efficiency,and reliable quality.Howev... With the acceleration of urbanization,prefabricated bridges have become a significant choice for transportation infrastructure construction due to their environmental friendliness,efficiency,and reliable quality.However,existing connection technologies still face shortcomings in construction efficiency,seismic performance,and cost control.This paper summarizes the process characteristics of commonly used connection technologies such as socket connections,grouted sleeve connections and corrugated pipe connections,and analyzes their seismic capacity and mechanical performance.In response to existing issues,two new technologies—separated steel connection and multi-chamber steel tube concrete connection—are proposed,and their comprehensive performance and economic efficiency are analyzed.The new connection technologies outperform traditional methods in construction efficiency,economic efficiency,and structural stability,with more reasonable force distribution,clearer load transfer paths,and significantly reduced overall costs.Existing technologies,such as socket connections,perform well in seismic performance but are complex to construct;grouted sleeve connections are mature in technology,but the quality of grouting is difficult to inspect.The separated steel connection and multi-chamber steel tube concrete connection technologies offer significant advantages.With the increasing demands for energy conservation and emission reduction,coupled with the rising labor costs,prefabricated bridge piers are undoubtedly poised to become one of the preferred technologies for bridge construction in China in the future.Therefore,in light of the current research landscape,this paper concludes by offering a forward-looking perspective on the development directions of connection methods for prefabricated bridge piers and identifying key areas for future research. 展开更多
关键词 Prefabricated Bridges Construction Efficiency Structural Stability Separated Steel connection Multi-Chamber Steel Tube Concrete connection
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Neural connectivity biotypes:predictors of clinical outcomes and improvement patterns of iTBS treatment in adolescents and young adults with depression
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作者 Weicheng Li Yanan Yin +18 位作者 Zerui You Min Zhang Chengyu Wang Xiaofeng Lan Siming Mai Fan Zhang Zhibo Hu Guanxi Liu Xiaoyu Chen Haiyan Liu Zhanjie Luo Yexian Zeng Yiying Chen Yifang Chen Robin Shao Hanna Lu Roger S McIntyre Yanling Zhou Yuping Ning 《General Psychiatry》 2025年第2期134-143,共10页
Background The heterogeneity of depression limits the treatment outcomes of intermittent theta burst stimulation(iTBS)and hinders the identification of predictive factors.This study investigated functional network con... Background The heterogeneity of depression limits the treatment outcomes of intermittent theta burst stimulation(iTBS)and hinders the identification of predictive factors.This study investigated functional network connectivity and predictors of iTBS treatment outcomes in adolescents and young adults with depression.Aim This study aimed to identify default mode network(DMN)-based connectivity patterns associated with varying iTBS treatment outcomes in depression.Methods Data from a randomised controlled trial of iTBS in depression(n=82)were analysed using a data-driven approach to classify homogeneous subgroups based on the DMN.Connectivity subgroups were compared on depressive symptoms and cognitive function at pretreatment and post-treatment.Furthermore,the predictive significance of baseline inflammatory cytokines on post-treatment outcomes was evaluated.Results Two distinct subgroups were identified.Subgroup 1 exhibited high heterogeneity and greater centrality in the posterior cingulate cortex and retrosplenial cortex,while subgroup 2 showed more homogeneous connectivity patterns and greater centrality in the temporoparietal junction and posterior inferior parietal lobule.No main effect for subgroup,treatment or subgroup×treatment interaction was revealed in the improvement of depressive symptoms.A significant subgroup×treatment interaction related to symbol coding improvement was detected(F=5.22,p=0.026).Within subgroup 1,the active group showed significantly greater improvement in symbol coding compared with the sham group(t=2.30,p=0.028),while baseline levels of interleukin-6 and C-reactive protein emerged as significant indicators for predicting improvements in symbolic coding(R2=0.35,RMSE(root-mean-square error)=5.72,p=0.013).Subgroup 2 showed no significant findings in terms of cognitive improvement or inflammatory cytokines predictions. 展开更多
关键词 default mode DEPRESSION functional network connectivity connectivity patterns identification predictive factorsthis randomised controlled trial default mode network intermittent theta burst stimulation itbs
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改进RRT-Connect算法的机器人路径规划研究 被引量:3
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作者 陈志澜 唐昊阳 《计算机科学与探索》 北大核心 2025年第2期396-405,共10页
针对标准RRT-Connect算法在路径规划中存在的路径冗长、转折较多和区域通过性欠缺问题,提出了一种新的改进RRT-Connect算法(TRRT-Connect)。采用改进RRT算法搜索并添加一个中间根节点,实现同时扩展四棵随机树,加快算法收敛速度。在随机... 针对标准RRT-Connect算法在路径规划中存在的路径冗长、转折较多和区域通过性欠缺问题,提出了一种新的改进RRT-Connect算法(TRRT-Connect)。采用改进RRT算法搜索并添加一个中间根节点,实现同时扩展四棵随机树,加快算法收敛速度。在随机点的选取上使用目标偏置策略,在新节点的生成上叠加引力场,同时融合贪婪搜索策略。结合新的动态步长调节方法,通过识别扫描区域内障碍物的个数动态选择合适的步长。对生成的初始路径使用双向剪枝优化方法,加快剪枝效率,剔除路径上的冗余节点。对路径转折处进行光滑处理,减少路径转折。在三种不同环境地图中进行仿真对比实验,结果表明,TRRT-Connect算法与标准RRT-Connect算法相比较,在路径长度、迭代次数和节点数上有较大改善,在密集障碍物区域的通过性较好,路径更加光滑且无转折,证明了该算法的有效性。同时将TRRT-Connect算法应用于现场实例仿真中,使得移动机器人的运输路径长度相较于传统固定路径降低了15.4%,且路径光滑,进一步验证了该算法的实用性。 展开更多
关键词 RRT-connect算法 动态步长调节 双向剪枝优化 路径规划
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高水平论文开放同行评议意见分析及启示——以H1Connect为例 被引量:1
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作者 刘晓娟 于姚 沈嘉宁 《数字图书馆论坛》 2025年第1期55-66,共12页
开放同行评议为论文评价提供了新的视角,分析高水平论文的评议意见特征,有利于评判优质论文、优化学术评价体系。以被全球生物医学领域权威开放同行评议平台H1 Connect专家推荐的、发表在顶级期刊上有关COVID-19的论文为高水平论文的典... 开放同行评议为论文评价提供了新的视角,分析高水平论文的评议意见特征,有利于评判优质论文、优化学术评价体系。以被全球生物医学领域权威开放同行评议平台H1 Connect专家推荐的、发表在顶级期刊上有关COVID-19的论文为高水平论文的典型案例,爬取这些论文在H1 Connect中的开放同行评议意见,从指标和文本两个层面分析专家评议意见所体现的对高水平论文的关注和认可程度、情感特征以及价值特征。研究发现,高水平论文能快速吸引专家的关注,但仅有少数引发热议。开放同行评议文本中存在一定数量的情感句,明确体现了专家的观点态度:正向评价居多,主要针对论文的总体表现;负向评价较少,主要针对论文采用的研究方法。开放同行评议意见认为论文的价值体现在学术领域和实践应用的多个维度,应用贡献更为突出。通过对高水平论文开放同行评议意见的分析,建议在学术评价体系中引入开放同行评议数据源,以提升学术评价的科学性和有效性。实际应用中,仍需进一步完善同行评议指标,深入挖掘评议文本中的关键要素,加强资源建设与技术融合,利用前沿技术智能解析评议文本的深层价值。 展开更多
关键词 开放同行评议 高水平论文 学术评价 H1 connect
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基于改进RRT-Connect算法的机械臂路径规划研究
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作者 郭晓杰 赵鼎 +2 位作者 赵子琪 程志博 李丹丹 《制造技术与机床》 北大核心 2025年第9期35-40,共6页
为解决快速遍历随机树算法(rapidly-exploringrandomtree,RRT-Connect)在复杂凹区域特定场景下收敛速度慢、路径质量差的问题,提出了一种改进的路径规划算法。该算法通过引入优化的搜索范围、自适应步长和路径修剪策略,提高了路径生成... 为解决快速遍历随机树算法(rapidly-exploringrandomtree,RRT-Connect)在复杂凹区域特定场景下收敛速度慢、路径质量差的问题,提出了一种改进的路径规划算法。该算法通过引入优化的搜索范围、自适应步长和路径修剪策略,提高了路径生成的成功率,缩短了路径搜索时间,并缩短了路径的总距离。实验结果表明,改进后的算法在路径生成效率和质量上具有显著优势,平均路径规划时间缩短11%,平均路径长度缩短30%。定性和定量结果均验证了该改进算法的有效性和优越性。 展开更多
关键词 路径规划 最优路径 RRT-connect 自适应步长 机械臂
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Effects of Changes in Hydrological Connectivity Induced by Spartina alterniflora Invasions on Suaeda salsa Community Evolution in Yellow River Estuary Wetland, China 被引量:1
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作者 ZHANG Xin LI Yunzhao +6 位作者 YU Junbao GUAN Bo YANG Jisong ZHOU Di WANG Xuehong LI Xue ZHOU Jie 《Chinese Geographical Science》 2025年第3期423-437,共15页
Spartina alterniflora invasions seriously threaten the structure and functions of coastal wetlands in China.In this study,the Suaeda salsa community in the Yellow River Estuary wetland was monitored using long-term La... Spartina alterniflora invasions seriously threaten the structure and functions of coastal wetlands in China.In this study,the Suaeda salsa community in the Yellow River Estuary wetland was monitored using long-term Landsat satellite images acquired from 1997 to 2020 to quantify the impact of changes in hydrological connectivity induced by S.alterniflora on neighboring vegetation com-munities.The results showed that S.alterniflora rapidly expanded in the estuary area at a rate of 4.91 km^(2)/yr from 2010 to 2020.At the same time,the hydrological connectivity of the area and the distribution of S.salsa changed significantly.Small tidal creeks dominated the S.alterniflora landscape.The number of tidal creeks increased significantly,but their average length decreased and they tended to develop in a horizontal tree-like pattern.Affected by the changes in hydrological connectivity due to the S.alterniflora invasion,the area of S.salsa decreased by 41.1%,and the degree of landscape fragmentation increased from 1997 to 2020.Variations in the Largest Patch Index(LPI)indicated that the S.alterniflora landscape had become the dominant landscape type in the Yellow River Estuary.The res-ults of standard deviation ellipse(SDE)and Pearson’s correlation analyses indicated that a well-developed hydrological connectivity could promote the maintenance of the S.salsa landscape.The degradation of most S.salsa communities is caused by the influence of S.alterniflora on the morphological characteristics of the hydrological connectivity of tidal creek systems. 展开更多
关键词 hydrological connectivity tidal creek Spartina alterniflora Suaeda salsa Yellow River Estuary wetland China
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基于复杂环境的RRT-Connect路径规划算法改进 被引量:1
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作者 谭仲万 袁宇浩 《科学技术与工程》 北大核心 2025年第19期8127-8134,共8页
针对RRT-Connect算法在复杂环境下路径规划效率低、避障能力差以及生成路径质量差等问题,提出一种改进的RRT-Connect算法。首先,提出一种双向目标偏向策略,增加算法的目标导向性以及路径规划效率。其次,提出一种避障优化策略,增加算法... 针对RRT-Connect算法在复杂环境下路径规划效率低、避障能力差以及生成路径质量差等问题,提出一种改进的RRT-Connect算法。首先,提出一种双向目标偏向策略,增加算法的目标导向性以及路径规划效率。其次,提出一种避障优化策略,增加算法在复杂环境下的主动避障能力以及通过能力。最后,加入路径重组策略和平滑策略对生成的初始路径进行优化处理,减少路径长度及拐点,提高路径质量。通过MATLAB将改进算法与其他算法在3种复杂环境下进行对比研究。仿真结果表明,改进算法相对规划时间更少、路径长度更短、采样次数更少、路径规划成功率更高,证明了改进算法在复杂环境下的有效性。 展开更多
关键词 RRT-connect算法 路径规划 双向目标偏向策略 避障优化策略 路径优化策略
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Look-ahead horizon-based energy optimization with traffic prediction for connected HEVs
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作者 XU Fu-guo SHEN Tie-long 《控制理论与应用》 北大核心 2025年第8期1534-1542,共9页
With the development of fast communication technology between ego vehicle and other traffic participants,and automated driving technology,there is a big potential in the improvement of energy efficiency of hybrid elec... With the development of fast communication technology between ego vehicle and other traffic participants,and automated driving technology,there is a big potential in the improvement of energy efficiency of hybrid electric vehicles(HEVs).Moreover,the terrain along the driving route is a non-ignorable factor for energy efficiency of HEV running on the hilly streets.This paper proposes a look-ahead horizon-based optimal energy management strategy to jointly improve the efficiencies of powertrain and vehicle for connected and automated HEVs on the road with slope.Firstly,a rule-based framework is developed to guarantee the success of automated driving in the traffic scenario.Then a constrained optimal control problem is formulated to minimize the fuel consumption and the electricity consumption under the satisfaction of inter-vehicular distance constraint between ego vehicle and preceding vehicle.Both speed planning and torque split of hybrid powertrain are provided by the proposed approach.Moreover,the preceding vehicle speed in the look-ahead horizon is predicted by extreme learning machine with real-time data obtained from communication of vehicle-to-everything.The optimal solution is derived through the Pontryagin’s maximum principle.Finally,to verify the effectiveness of the proposed algorithm,a traffic-in-the-loop powertrain platform with data from real world traffic environment is built.It is found that the fuel economy for the proposed energy management strategy improves in average 17.0%in scenarios of different traffic densities,compared to the energy management strategy without prediction of preceding vehicle speed. 展开更多
关键词 look-ahead horizon connected and automated vehicle(CAV) hybrid electric vehicle(HEV) energy efficiency optimization traffic prediction
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改进RRT-Connect算法下的码垛机械臂避障轨迹规划
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作者 赵彬湘 焉峻 李金泉 《成组技术与生产现代化》 2025年第1期25-30,共6页
针对小型包装件码垛场景中码垛机器人的避障轨迹规划问题,从更快地得到光滑且无碰撞的路径、缩短时耗、提高码垛机器人工作效率的目的出发,在轨迹规划基本算法RRT-Connect的基础上加入目标偏置采样和自适应步长调节机制,使随机树能更快... 针对小型包装件码垛场景中码垛机器人的避障轨迹规划问题,从更快地得到光滑且无碰撞的路径、缩短时耗、提高码垛机器人工作效率的目的出发,在轨迹规划基本算法RRT-Connect的基础上加入目标偏置采样和自适应步长调节机制,使随机树能更快地向目标方向拓展,同时引入路径修剪和重连策略来减少规划路径的节点数量,使整个路径更加平滑,实现了对基本RRT-Connect算法的改进。对比传统算法及改进后算法的规划时间、路径节点数量和路径长度等数据,并利用机械臂模型进行了仿真分析。结果表明,改进后算法更为高效。 展开更多
关键词 码垛机器人 机械臂 轨迹规划 RRT-connect算法 动态步长 重连策略
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Spatiotemporal Analysis of Pavement Roughness Using Connected Vehicle Data for Asset Management
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作者 Jijo K. Mathew Jairaj Desai +2 位作者 Rahul Suryakant Sakhare Jeremy Hunter Darcy M. Bullock 《Journal of Transportation Technologies》 2025年第1期1-16,共16页
Pavement condition monitoring and its timely maintenance is necessary to ensure the safety and quality of the roadway infrastructure. The International Roughness Index (IRI) is a commonly used measure to quantify road... Pavement condition monitoring and its timely maintenance is necessary to ensure the safety and quality of the roadway infrastructure. The International Roughness Index (IRI) is a commonly used measure to quantify road surface roughness and is a critical input to asset management. In Indiana, the IRI statistic contributes to roughly half of the pavement quality index computation used for asset management. Most agencies inventory IRI once a year, however, pavement conditions vary much more frequently. The objective of this paper is to develop a framework using crowdsourced connected vehicle data to identify and detect temporal changes in IRI. Over 3 billion connected vehicle records in Indiana were analyzed across 30 months between 2022 and 2024 to understand the spatiotemporal variations in roughness. Annual comparisons across all major interstates in Indiana showed the miles of interstates classified as “Good” decreased from 1896 to 1661 miles between 2022 and 2024. The miles of interstate classified as “Needs Maintenance” increased from 82 to 120 miles. A detailed case study showing monthly and daily changes of estimated IRI on I-65 are presented along with supporting dashcam images. Although the crowdsourced IRI estimates are not as robust as traditional specialized pavement profilers, they can be obtained on a monthly, weekly, or even daily basis. The paper concludes by suggesting a combination of frequent crowdsourced IRI and commercially available dashcam imagery of roadway can provide an agile and responsive mechanism for agencies to implement pavement asset management programs that can complement existing annual programs. 展开更多
关键词 connected Vehicles PAVEMENT Pavement Quality ROUGHNESS IRI Dashcam
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一类单圈图的最小sum-connectivity能量
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作者 赵可 朱芳 赵璇 《重庆理工大学学报(自然科学)》 北大核心 2025年第9期240-248,共9页
定义C_(g)∪S_(t)为将一个圈C_(g)中的某个顶点与一个星图S_(t)中的某个顶点相连后构造出的具有n个顶点的单圈图。图G的sum-connectivity矩阵S(G)=(s_(ij))_(n×n)是一n阶矩阵,其中,若顶点v_(i)与顶点v_(j)邻接,则s_(ij)=1/√d_(G)(... 定义C_(g)∪S_(t)为将一个圈C_(g)中的某个顶点与一个星图S_(t)中的某个顶点相连后构造出的具有n个顶点的单圈图。图G的sum-connectivity矩阵S(G)=(s_(ij))_(n×n)是一n阶矩阵,其中,若顶点v_(i)与顶点v_(j)邻接,则s_(ij)=1/√d_(G)(v_(i))+d_(G)(v_(j)),若v_(i)与点v_(j)不邻接,或i=j,则s_(ij)=0。图G的sum-connectivity能量定义为sum-connectivity矩阵特征值的绝对值之和。考虑了该类单圈图中的sum-connectivity能量的极小值问题。根据sum-connectivity能量的定义及其性质得到4种图变换,同时得到该类单圈图sum-connectivity能量的变化规律,最后得到S_(n)^(3)在该类单圈图中具有最小的sum-connectivity能量,其中S_(n)^(3)表示圈C_(3)上某个顶点连接n-3条悬挂边的单圈图。 展开更多
关键词 单圈图 特征多项式 特征值 sum-connectivity能量
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融合改进RRT–Connect与APF的路径规划算法
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作者 赵卫东 刘立磊 吕红兵 《安徽工业大学学报(自然科学版)》 2025年第4期401-409,417,共10页
为提高无人驾驶车辆路径规划的实时性与安全性,提出一种融合改进双向快速扩展随机树(RRT–Connect)和人工势场(APF)的协同优化算法。首先采用动态步长策略,根据节点与障碍物间距自适应调整扩展步长,显著提高路径搜索效率;其次融合APF特... 为提高无人驾驶车辆路径规划的实时性与安全性,提出一种融合改进双向快速扩展随机树(RRT–Connect)和人工势场(APF)的协同优化算法。首先采用动态步长策略,根据节点与障碍物间距自适应调整扩展步长,显著提高路径搜索效率;其次融合APF特性,利用其引力分量引导随机树向目标点方向偏置采样以加快收敛速度,同时借助APF斥力分量实现障碍物规避以增强路径安全性;进而引入双向剪枝策略结合三次B样条曲线优化,有效缩短路径长度并提升轨迹平滑度;特别地,通过改进APF斥力函数增加目标点间距离分量,解决目标点不可达问题,又确保车辆在动态环境中能稳定抵达目标位置。为验证算法有效性,基于机器人操作系统(ROS)搭建仿真平台,在多种复杂障碍物场景下进行测试。结果表明:与基准RRT和RRT–Connect算法,本文提出的融合优化算法通过动态步长策略和采样函数改进,使路径节点数量分别减少约30%和12%,路径长度分别缩短约30%和13%,搜索时间分别降低约50%和3%;经双向剪枝策略和三次B样条曲线的联合优化处理,路径平滑度进一步提升、长度进一步缩短;改进后的斥力函数不仅有效解决了目标点不可达问题,同时提升了算法在动态复杂环境中的实时避障能力。 展开更多
关键词 RRT–connect 人工势场法 动态步长 自适应采样 无人驾驶 实时避障 运动平滑 路径规划
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From Silk Road to Global Gateway Rooted in tradition and thriving on creativity, Chengdu is building a global image through culture and connection
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作者 Tan Ping Hu Haoge 《China Report ASEAN》 2025年第6期74-75,共2页
Chengdu,a city rich in history and culture,is a beacon of China’s storied past embracing a distinct postmodern vibe.As an important hub along the ancient Silk Road,it has long been a meeting point for di!erent civili... Chengdu,a city rich in history and culture,is a beacon of China’s storied past embracing a distinct postmodern vibe.As an important hub along the ancient Silk Road,it has long been a meeting point for di!erent civilizations,where ideas and cultures have exchanged and thrived.Driven by the vision of a community with a shared future for mankind in recent years,Chengdu scholars and media have opened their arms to the world,engaging in multilingual storytelling.These efforts share the warmth and goodwill of a city consistently ranked one of the happiest in China.Through consistent efforts,new insights have emerged—ideas and aspirations intended to be shared with readers both at home and abroad. 展开更多
关键词 history shared future silk road global gateway CREATIVITY CULTURE connectION CIVILIZATIONS
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Partner 2 Connect Annual Meeting 2024
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《China Standardization》 2025年第1期53-53,共1页
January 30,Geneva,Switzerland&online As we step into a pivotal moment in the journey toward universal and meaningful connectivity,the Partner2Connect(P2C)Annual Meeting promises to be a transformative gathering of... January 30,Geneva,Switzerland&online As we step into a pivotal moment in the journey toward universal and meaningful connectivity,the Partner2Connect(P2C)Annual Meeting promises to be a transformative gathering of global leaders,innovators,and changemakers.This year’s programme reflects the dynamic and evolving spirit of P2C,offering engaging discussions,interactive sessions,and valuable networking opportunities.Together,we will not only celebrate our collective achievements but also confront the challenges that remain—ensuring that progress toward digital inclusion is sustainable and equitable. 展开更多
关键词 connect COLLECTIVE GATHERING
原文传递
Propofol-Induced Moderate-Deep Sedation Modulates Pediatric Neural Activity:A Functional Connectivity Study
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作者 Qiang Zheng Yiyu Zhang +2 位作者 Lin Zhang Jian Wang Jungang Liu 《iRADIOLOGY》 2025年第1期61-71,共11页
Background:Previous studies have demonstrated the underlying neurophysiologic mechanism during general anesthesia in adults.However,the mechanism of propofol-induced moderate-deep sedation(PMDS)in modulating pediatric... Background:Previous studies have demonstrated the underlying neurophysiologic mechanism during general anesthesia in adults.However,the mechanism of propofol-induced moderate-deep sedation(PMDS)in modulating pediatric neural activity remains unknown,which therefore was investigated in the present study based on functional magnetic resonance imaging(fMRI).Methods:A total of 41 children(5.10�1.14 years,male/female 21/20)with fMRI were employed to construct the functional connectivity network(FCN).The network communication,graph-theoretic properties,and network hub identification were statistically analyzed(t test and Bonferroni correction)between sedation(21 children)and awake(20 children)groups.All involved analyses were established on the whole-brain FCN and seven sub-networks,which included the default mode network(DMN),dorsal attentional network(DAN),salience network(SAN),auditory network(AUD),visual network(VIS),subcortical network(SUB),and other networks(Other).Results:Under PMDS,significant decreases in network communication were observed between SUB-VIS,SUB-DAN,and VIS-DAN,and between brain regions from the temporal lobe,limbic system,and subcortical tissues.However,no significant decrease in thalamus-related communication was observed.Most graph-theoretic properties were significantly decreased in the sedation group,and all graphical features of the DMN showed significant group differences.The superior parietal cortex with different neurological functions was identified as a network hub that was not greatly affected.Conclusions:Although the children had a depressed level of neural activity under PMDS,the crucial thalamus-related communication was maintained,and the network hub superior parietal cortex stayed active,which highlighted clinical prac-tices that the human body under PMDS is still perceptible to external stimuli and can be awakened by sound or touch. 展开更多
关键词 functional connectivity network moderate-deep sedation neural activity PEDIATRIC PROPOFOL
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Biological processes involved in mechanical force transmission in connective tissue:Linking bridges for new therapeutic applications in the rehabilitative field
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作者 AUGUSTO FUSCO STEFANO BONOMI LUCA PADUA 《BIOCELL》 2025年第1期1-5,共5页
Connective tissue is a dynamic structure that reacts to environmental cues to maintain homeostasis,including mechanical properties.Mechanical load influences extracellular matrix(ECM)—cell interactions and modulates ... Connective tissue is a dynamic structure that reacts to environmental cues to maintain homeostasis,including mechanical properties.Mechanical load influences extracellular matrix(ECM)—cell interactions and modulates cellular behavior.Mechano-regulation processes involve matrix modification and cell activation to preserve tissue function.The ECM remodeling is crucial for force transmission.Cytoskeleton components are involved in force sensing and transmission,affecting cellular adhesion,motility,and gene expression.Proper mechanical loading helps to maintain tissue health,while imbalances may lead to pathological processes.Active and passive movement,including manual mobilization,improves connective tissue elasticity,promotes ECM-cell homeostasis,and reduces fibrosis.In rehabilitation,understanding mechanical-regulation processes is necessary for ameliorating and developing treatments aimed at preserving tissue elasticity and preventing fibrosis.In this commentary,we aim to globally describe the biological processes involved in mechanical force transmission in connective tissue as support for translational studies and clinical applications in the rehabilitation field. 展开更多
关键词 connective tissue Cellular mechanotransduction INTEGRINS Translational science
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