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RRT Autonomous Detection Algorithm Based on Multiple Pilot Point Bias Strategy and Karto SLAM Algorithm

Computers, Materials & Continua 2024年第2期78卷 2111-2136页

作者： Lieping Zhang Xiaoxu shi Liu Tang Yilin Wang jiansheng Peng Jianchu Zou Key Laboratory of Advanced Manufacturing and Automation Technology(Guilin University of Technology) Education Department of Guangxi Zhuang Autonomous RegionGuilin541006China College of Mechanical and Control Engineering Guilin University of TechnologyGuilin541006China Guilin Mingfu Robot Technology Company Limited Guilin541199China Key Laboratory of AI and Information Processing(Hechi University) Education Department of Guangxi Zhuang Autonomous RegionYizhou546300China

A Rapid-exploration Random Tree(RRT)autonomous detection algorithm based on the multi-guide-node deflection strategy and Karto Simultaneous Localization and Mapping(SLAM)algorithm was proposed to solve the problems of low efficiency of detecting frontier boundary points and drift distortion in the process of map building in the traditional RRT algorithm in the autonomous detection strategy of mobile robot.Firstly,an RRT global frontier boundary point detection algorithm based on the multi-guide-node deflection strategy was put forward,which introduces the reference value of guide nodes’deflection probability into the random sampling function so that the global search tree can detect frontier boundary points towards the guide nodes according to random probability.After that,a new autonomous detection algorithm for mobile robots was proposed by combining the graph optimization-based Karto SLAM algorithm with the previously improved RRT algorithm.The algorithm simulation platform based on the Gazebo platform was built.The simulation results show that compared with the traditional RRT algorithm,the proposed RRT autonomous detection algorithm can effectively reduce the time of autonomous detection,plan the length of detection trajectory under the condition of high average detection coverage,and complete the task of autonomous detection mapping more efficiently.Finally,with the help of the ROS-based mobile robot experimental platform,the performance of the proposed algorithm was verified in the real environment of different obstacles.The experimental results show that in the actual environment of simple and complex obstacles,the proposed RRT autonomous detection algorithm was superior to the traditional RRT autonomous detection algorithm in the time of detection,length of detection trajectory,and average coverage,thus improving the efficiency and accuracy of autonomous detection.

关键词： Autonomous detection RRT algorithm mobile robot ROS Karto SLAM algorithm

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Multifunctional RGD coated a single-atom iron nanozyme:A highly selective approach to inducing ferroptosis and enhancing immunotherapy for pancreatic cancer

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Nano Research 2024年第6期17卷 5469-5478页

作者： Haoqi Pan Xu Chen Mingming Xiao He Xu jiansheng Guo Zhiyi Lu Dong Cen Xianjun Yu Si shi Department of Pancreatic Surgery Fudan University Shanghai Cancer CenterShanghai 200032China Department of Oncology Shanghai Medical CollegeFudan UniversityShanghai 200032China Shanghai Pancreatic Cancer Institute Shanghai 200032China Pancreatic Cancer Institute Fudan UniversityShanghai 200032China Key Laboratory of Advanced Fuel Cells and Electrolyzers Technology of Zhejiang Province Qianwan Institute of CNITECHNingbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo 315201China Department of Pathology of Sir Run Run Shaw Hospital Zhejiang University School of MedicineHangzhou 310016China Key Laboratory of Laparoscopic Technology of Zhejiang Province Department of General SurgerySir Run Run Shaw HospitalZhejiang University School of MedicineHangzhou 310016China

Nanozyme is a new promising approach to cancer therapy for its ability to induce ferroptosis by activating H_(2)O_(2)via a traditional radical pathway and enhance cancer immunotherapy.However,short half-life period of hydroxyl radical(·OH)results in unsatisfied effectiveness.Herein,we synthesized a single-atom iron nanozyme(Fe-SAzyme),which can activate H_(2)O_(2)via a non-radical pathway to generate Fe-based reactive oxygen species(ROS)(O=FeO_(3)=O)for promoting the ferroptosis of pancreatic cancer cells.This Fe-SAzyme could be specifically phagocytosed by pancreatic cancer cells,increasing ROS levels and inhibiting glutathione(GSH)synthesis,which activates ferroptosis.Tumor magnetic resonance imaging(MRI)showed decreased T2 signal after intravenous injection of RGD@Fe-AC(AC=activated carbon).Moreover,RGD@Fe-AC promoted dendritic cell(DC)maturation,overcame Treg-mediated immunosuppression,activated T cells to trigger adaptive immune responses,and enhanced the efficacy ofα-PD-L1 immunotherapy.Our research demonstrated that RGD@Fe-AC provided a straightforward,easily implemented,and selective approach for pancreatic cancer treatment and immunotherapy.

关键词： single-atom iron nanozyme pancreatic cancer immunotherapy ferroptosis

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Dealing with the Spatial Synthetic Heterogeneity of Aquifers in the North China Plain:A Case Study of Luancheng County in Hebei Province

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Acta Geologica Sinica(English Edition) 2012年第1期86卷 226-245页

作者： MA Rong shi jiansheng LIU Jichao The Institute of Hydrogeology and Environmental Geology ShijiazhuangHebei 050803

The complexity of alluvial-pluvial fan depositional systems makes the detailed characterization of their heterogeneity difficult, yet such a detailed characterization is commonly needed for construction of reliable groundwater models. Traditional models mainly focus on using a single aquifer property to qualitatively or semi-quantitatively characterize the heterogeneity of aquifer, so that they are unable to quantitatively reflect the synthetic heterogeneity of all aquifer properties. In this paper, we propose the heterogeneity synthetic index （HSI） for quantitative characterization of synthetic heterogeneity of an aquifer. The proposed calculation process involves four steps：（1） estimation of the hydraulic conductivity of a sediment sample using the cloud-Markov model, （2） establishment of the sedimentary microfacies distribution model through the Markov chain, （3） characterization of the distribution model of hydrogeological parameters using the improved sequential simulation method according to the ＂facies-controlled modeling＂ technique, and （4） application of the entropy weight method to calculate the weight coefficient of the above aquifer properties. The HSI of an aquifer is calculated by superposition of these models according to the corresponding weight coefficient. This approach was applied to the Luancheng aquifer deposit in the southeast Hutuo River alluvial-pluvial fan in the North China Plain （NCP）. The results have demonstrated that aquifer 3 which was formed in the middle Pleistocene has the strongest heterogeneity, with an HSI of 0.25-0.75. Aquifer 4 formed in the early Pleistocene shows an intermediate heterogeneity, with the HSI ranging 0.35-0.75. The weakest heterogeneity was found in aquifers 1 and 2 formed in the Holocene and late Pleistocene, with HSI values of 0.40-0.75 and 0.40- 0.80, respectively. The heterogeneity of all the four aquifers is relatively strong in the radial direction of the Huai River alluvial-pluvial fan due to the abrupt change of microfacies. In contrast, in the radia

关键词： aquifer heterogeneity hydraulic conductivity porosity Markov

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东海中南部澳洲鲐繁殖群体生物学特征

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中国水产科学 2024年第4期31卷 429-438页

作者：史雨楠严利平李建生中国水产科学研究院东海水产研究所农业农村部东海渔业资源开发利用重点实验室上海海洋大学海洋科学学院

为研究东海海域澳洲鲐(Scomberaustralasicus)繁殖群体的生物学特征,依据2016—2023年1—4月在东海中南部采集的227尾澳洲鲐样本,分析了澳洲鲐繁殖群体的叉长、体重、摄食等级、肥满度、性腺指数、性比及肌肉含量等生物学特征。结果显示... 详细信息

为研究东海海域澳洲鲐(Scomberaustralasicus)繁殖群体的生物学特征,依据2016—2023年1—4月在东海中南部采集的227尾澳洲鲐样本,分析了澳洲鲐繁殖群体的叉长、体重、摄食等级、肥满度、性腺指数、性比及肌肉含量等生物学特征。结果显示,澳洲鲐繁殖群体性别间的叉长和体重关系无显著差异(P>0.05),雌雄个体合并拟合的叉长和体重关系式为:W=3×10–6FL3.2558。1月为澳洲鲐的越冬期, 2—4月为繁殖期。澳洲鲐的产卵高峰期集中在3月,到4月下旬,已经产卵的澳洲鲐数量比例增大。在性腺发育同等情况下,雌性澳洲鲐在繁殖期间性腺指数始终高于雄性澳洲鲐,而肌肉含量却小于雄性澳洲鲐。摄食强度在越冬期到繁殖期前后是先下降后上升的状态,肥满度则是先上升后下降,最后恢复到与繁殖期前相近的水平。2月繁殖初期雄性多于雌性,到3—4月繁殖中后期雌性数量多于雄性。这种繁殖期间性比的变化符合最大限度实现世代补充和繁殖收益最大化的繁殖策略。综上,东海中南部澳洲鲐的繁殖高峰期集中在3月,在进入繁殖期后,性腺发育过程中会减少摄食,生长缓慢,机体的部分肌肉组织会转化为性腺以满足生殖所需。

关键词：澳洲鲐繁殖群体生物学特征东海

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Suitability assessment of deep groundwater for drinking, irrigation and industrial purposes in Jiaozuo City, Henan Province, north China

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Chinese Science Bulletin 2013年第25期58卷 3098-3110页

作者： shi jiansheng MA Rong LIU JiChao ZHANG YiLong Institute of Hydrogeology and Environmental Geology

Groundwater has been a major natural resource for human consumption in north China. It is necessary to appreciate the suitability of deep groundwater for drinking, agricultural irrigation, and industrial uses in this region. To this end, a total of 47 groundwater samples were collected from the study area; by comparing the concentrations of different hydrochemical variables with quality standard values, the variable fuzzy set (VFS) was applied to calculate the groundwater quality index (GQI) for various purposes, respectively. Afterward GQI spatial distribution maps were constructed using a geographic information system (GIS) tool to delineate spatial variations of groundwater quality. In this case study, the GQI spatial distribution maps reveal that the areas covered by "Maximum Permissible" groundwater for varying purposes (drinking, irrigation, and industrial) is 1377.2; 2354.7; and 3854.8 km2, respectively. The groundwater in the eastern part of the study area is suitable for drinking, with the southwestern region as the irrigation water source; the entire study area is acceptable for use in industrial, except the western part of Jiaozuo City. Therefore, the GQI spatial distribution maps can provide useful information for non-technical decision makers for better sustainable groundwater resources management.

关键词：工业用途农业灌溉中国北方水饮用焦作市适宜性评价河南省地下水水质

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应用改进RRT_Connect算法的移动机器人路径规划

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科技导报 2024年第8期42卷 111-119页

作者：史小旭张烈平唐柳董路熙彭建盛广西高校先进制造与自动化技术重点实验室桂林541006 贺州学院人工智能学院贺州542899 广西高校人工智能与信息处理重点实验室河池546300

针对复杂未知环境下的移动机器人路径规划问题,提出一种优化已搜索节点和已规划部分路径的改进RRT_Connect算法。算法引入了终点和已搜索节点目标偏向策略,该策略在随机采样函数中引入终点和已搜索节点偏向概率基准值,使随机采样点按随... 详细信息

针对复杂未知环境下的移动机器人路径规划问题,提出一种优化已搜索节点和已规划部分路径的改进RRT_Connect算法。算法引入了终点和已搜索节点目标偏向策略,该策略在随机采样函数中引入终点和已搜索节点偏向概率基准值,使随机采样点按随机概率设定为终点或已搜索节点;通过筛选有效新节点和一定范围内邻节点的父节点,优化路径规划成本,使规划路径趋于平滑。仿真结果表明,提出的改进RRT_Connect算法所规划的路径在平均转弯次数、平均规划路径长度和平均规划成功率等指标较改进前更优。

关键词： RRT_Connect算法移动机器人路径规划目标偏向策略

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Fabrication and luminescence of highly transparent C12A7:Tb^(3+)glass-ceramics via in-situ crystallization from aerodynamic levitation processed glasses

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Journal of Rare Earths 2023年第11期41卷 1696-1702,I0002页

作者： Yaling Zhang Lingcong Fan Xuefeng Wang jiansheng Xie Ying shi School of Materials Science and Engineering Shanghai UniversityShanghai200444China

Rare earth doped 12CaO·7Al_(2)O_(3)(C12A7)glass-ceramics are one of attractive photonic materials due to their high transparency,high luminescent efficiency and eco-friendly nature.A series of C12A7 glasses with different Tb^(3+)doping concentrations was prepared by aerodynamic levitation method.The C12A7:Tb glass-ceramics were obtained via in-situ growth from the glasses with the identical chemical composition at 800℃.The microstructure observation demonstrates that the elemental distributions of Ca and Al are homogeneous in the glass-ceramics and the grain size of C12A7 is 4-70 nm.The in-line transmittance of glass-ceramics reaches as high as 82%at 1500 nm.The emission spectra of the C12A7:Tb glass-ceramics present characteristic Tb^(3+)emission peaks at 486 nm(^(5)D_(4)→^(7)F_6),541 nm(^(5)D_(4)→^(7)F_(5)),585 nm(^(5)D_(4)→^(7)F_(4))and 621 nm(^(5)D_(4)→^(7)F_(3)).The photolumine scence lifetime of C12A7:0.3%Tb glass-ceramic is 1.9 ms.Compared with the emission intensity of the glasses,that of the glass-ceramics increases due to the reducing in concentration of oxygen vacancy associated with network forming(NWF)cations.The highly transparent C12A7:Tb glass-ceramics may be a promising candidate for green light source in solid state lighting.

关键词： C12A7:Tb Aerodynamic levitation method Glass-ceramics Crystallization Luminescence Rare earths

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基于健康与恢复力的生态系统退化风险研究——以坝上高原察汗淖尔流域为例

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中国地质 2024年第3期51卷 1034-1045页

作者：陈鹏张冰马荣石建省司乐天吴俊赵乐凡中国地质科学院水文地质环境地质研究所河北石家庄050061 中国地质调查局第四纪年代学与水文环境演变重点实验室河北石家庄050061 中国地质调查局自然资源航空物探遥感中心北京100083 河北地质大学河北石家庄050031 河北工程大学河北邯郸056038 中国地质大学(北京) 北京100083

【研究目的】基于生态系统的健康状况与恢复力,构建湖泊流域生态系统退化风险评估体系,从流域尺度为生态环境保护及可持续发展提供科学依据。【研究方法】以坝上高原察汗淖尔流域为例,创建生态系统健康与恢复力交互风险评估矩阵,建立生... 详细信息

【研究目的】基于生态系统的健康状况与恢复力,构建湖泊流域生态系统退化风险评估体系,从流域尺度为生态环境保护及可持续发展提供科学依据。【研究方法】以坝上高原察汗淖尔流域为例,创建生态系统健康与恢复力交互风险评估矩阵,建立生态退化风险评估体系,开展察汗淖尔流域生态系统退化风险评估。【研究结果】察汗淖尔流域内91.10%的区域生态健康状态处于良好,6.66%为优秀;流域22.76%的区域生态恢复力等级为1~2级,75.00%处于3~4级。交互评估结果表明流域27.51%的区域为低生态退化风险较状态,70.25%的区域处于中等状态。【结论】察汗淖尔流域生态系统总体较好,但局部地区由于恢复力较差,导致生态退化风险处于中等。本次研究所提出的评估方法可精准划分流域尺度生态退化风险等级,为科学制定精准生态保护与退化控制措施提供决策依据。

关键词：生态系统健康生态恢复力风险评估察汗淖尔流域水文地质调查工程坝上高原内蒙古

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Perfluoroalkyl acids(PFAAs) in urban surface water of shijiazhuang, China: Occurrence, distribution,sources and ecological risks

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Journal of Environmental Sciences 2023年第3期125卷 185-193页

作者： Xiaotong Li Yuan Wang Chengjing Qian Zhixin Zheng Yali shi jiansheng Cui Yaqi Cai College of Environmental Science and Engineering Hebei University of Science and TechnologyShijiazhuang 050018China State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental ScienceUniversity of Chinese Academy of SciencesBeijing 100085China Nutrition&Health Research Institute COFCO CorporationBeijing 102209China School of Environment Hangzhou Institute for Advanced StudyUCASHangzhou 310024China

It is extremely important to analyze the contaminative behaviors of Perfluoroalkyl acids(PFAAs) due to their serious threats to urban environments which are closely related to humans. Current study aimed to explore the distribution, source apportionment and ecological risk assessment of PFAAs in surface water from shijiazhuang, China. The concentrations of ΣPFAAs ranged from 19.5 to 125.9 ng/L in the investigation area. Perfluorobutanesulfonic acid(PFBS) and perfluoropentanoic acid(PFPeA) were the predominant contaminants(mean value: 14.3 ng/L and 16.6 ng/L, respectively). The distribution of PFAAs according to geospatial analysis and hierarchical clustering analysis(HCA) showed that higher levels of ΣPFAAs were detected in the southern surface water of shijiazhuang and there was a stepwise decrease from the wet season to the dry season. Furthermore, based on source apportionment,the dominant potential sources were found to be wastewater treatment plant(WWTP) effluents and industrial discharge. The risk quotients(RQs) revealed low ecological risks of all PFAAs for aquatic organisms in shijiazhuang surface water. Collectively, this study provided basic data for regulatory strategies for controlling PFAA pollutions in urban surface water.

关键词： Perfluoroalkyl acids Distribution Source apportionment Risk assessment Urban surface water

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聚乙烯/碳纤维复合材料的制备及其各向异性传导行为

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复合材料学报 2024年第6期41卷 3053-3059页

作者：石素宇吕建胜张晨辉任智琳许乾坤郑国强河南工程学院材料工程学院郑州大学化工学院

各向异性传导高分子复合材料(ACPC)因其独特的各向异性导电、导热等特性在集成电路、传感器件、热管理等领域具有巨大的应用潜力。本文以碳纤维(CF)和高密度聚乙烯(HDPE)膜为原料，碳纤维经高温预处理后，通过超声分散和真空抽滤工艺制... 详细信息

各向异性传导高分子复合材料(ACPC)因其独特的各向异性导电、导热等特性在集成电路、传感器件、热管理等领域具有巨大的应用潜力。本文以碳纤维(CF)和高密度聚乙烯(HDPE)膜为原料，碳纤维经高温预处理后，通过超声分散和真空抽滤工艺制备三维碳纤维网络，再采用热压成型技术将其与聚乙烯膜复合制备具有各向异性传导行为的HDPE/CF复合材料。通过DSC、SEM、TG及导电性能测试研究了复合材料的微结构、热性质和电性能，采用集成电路和红外热像仪对复合材料的各向异性传导行为进行监测。聚乙烯层与碳纤维网层交替排列且结合紧密；这种交替多层结构赋予了HDPE/CF复合材料层内导电、层间绝缘特性，呈现典型的各向异性传导行为。HDPE/CF复合材料在X方向和Y方向具有优异的导电性能(电导率高达85.71 S/m)，高出Z方向5～7个数量级。交替多层结构和碳纤维网的引入显著提高了HDPE/CF复合材料的热稳定性能，其初始热分解温度相对HDPE膜提高了约35℃。该复合材料具有优异的电子载流能力和定向传导能力，在电路连接、定向导电、热管理等领域具有巨大的应用潜力。

关键词：碳纤维高密度聚乙烯各向异性传导导电导热热压成型交替多层结构

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