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Cy-CNN: cylinder convolution based rotation-invariant neural network for point cloud registration

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Science China(Information Sciences) 2023年第5期66卷 73-87页

作者： hengwang ZHAO Zhidong LIANG yuesheng he Chunxiang WANG Ming YANG Department of Automation Shanghai Jiao Tong University Research Institute of Robotics Shanghai Jiao Tong University

Point cloud registration is a challenging problem in the condition of large initial misalignments and noises. A major problem encountered in the registration algorithms is the definition of correspondence between two point clouds. Point clouds contain rich geometric information and the same geometric structure implies the same feature even if they are in diferent poses, which motivates us to seek a rotation-invariant feature representation for calculating the correspondence. This work proposes a rotation-invariant neural network for point cloud registration. To acquire rotation-invariant features, we firstly propose a rotationinvariant point cloud representation(RIPR) at the input level. Instead of using the original coordinates,we propose to use point pair features(PPF) and the transformed coordinates in the local reference frame(LRF) to represent a point. Then, we design a new convolution operator named Cylinder-Conv which utilizes the symmetry of cylinder-shaped voxels and the hierarchical geometry information of the surface of3D shapes. By specifying the cylinder-shaped structures and directions, Cylinder-Conv can better capture the local neighborhood geometry of each point and maintain rotation-invariance. Finally, we combine RIPR and Cylinder-Conv to extract normalized rotation-invariant features to generate the correspondence and perform a diferentiable singular value decomposition(SVD) step to estimate the rigid transformation. The proposed network presents state-of-the-art performance on point cloud registration. Experiments show that our method is robust to initial misalignments and noises.

关键词： deep learning point cloud registration rotation invariant computer vision

Infrastructure-Based Vehicle Localization System for Indoor Parking Lots Using RGB-D Cameras

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Journal of Shanghai Jiaotong university(Science) 2023年第1期28卷 61-69页

作者：曹炳全贺越生庄瀚洋杨明 Department of Automation Shanghai Jiao Tong UniversityShanghai 200240China Key Laboratory of System Control and Information Processing of Ministry of Education Shanghai 200240China Shanghai Engineering Research Center of Intelligent Control and Management Shanghai 200240China University of Michigan-Shanghai Jiao Tong University Joint Institute Shanghai Jiao Tong UniversityShanghai 200240China

Accurate vehicle localization is a key technology for autonomous driving tasks in indoor parking lots,such as automated valet ***,infrastructure-based cooperative driving systems have become a means to realizing intelligent *** this paper,we propose a novel and practical vehicle localization system using infrastructure-based RGB-D cameras for indoor parking *** the proposed system,we design a depth data preprocessing method with both simplicity and efficiency to reduce the computational burden resulting from a large amount of ***,the hardware synchronization for all cameras in the sensor network is not implemented owing to the disadvantage that it is extremely cumbersome and would significantly reduce the scalability of our system in mass ***,to address the problem of data distortion accompanying vehicle motion,we propose a vehicle localization method by performing template point cloud registration in distributed depth ***,a complete hardware system was built to verify the feasibility of our solution in a real-world *** in an indoor parking lot demonstrated the effectiveness and accuracy of the proposed vehicle localization system,with a maximum root mean squared error of 5 cm at 15Hz compared with the ground truth.

关键词： infrastructure-based RGB-D camera vehicle localization point cloud registration

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一种面向固态激光雷达的简易标定与验证方法

上海交通大学学报 2021年第S2期55卷 98-102,109页

作者：杨逸文贺越生王春香杨明上海交通大学自动化系系统控制与信息处理教育部重点实验室上海工业智能管控工程技术研究中心上海200240

为了解决固态激光雷达外参标定繁琐与验证其标定结果较为困难的问题,提出了一种面向固态激光雷达的简易标定与验证方法.该方法设计了一种简易的标定场和标志物,随后利用标志物完成激光雷达的角度标定,再通过测绘方法完成激光雷达的距离... 详细信息

为了解决固态激光雷达外参标定繁琐与验证其标定结果较为困难的问题,提出了一种面向固态激光雷达的简易标定与验证方法.该方法设计了一种简易的标定场和标志物,随后利用标志物完成激光雷达的角度标定,再通过测绘方法完成激光雷达的距离标定,以此来减少角度外参与距离外参的相关性,并保证标定结果的精度.最后通过比较计算得出外参误差,验证激光雷达标定结果.实验结果表明该方法合理有效,且大幅减少了激光雷达标定和验证结果所需要的设备准备时间和成本,具有一定的应用价值.

关键词：激光雷达外参标定验证方法

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一种面向泊车场景智能车辆轨迹规划方法

上海交通大学学报 2023年第3期57卷 345-353页

作者：林淳贺越生方兴其王春香上海交通大学自动化系上海200240

局部轨迹规划是自主代客泊车系统的关键技术之一,在该场景下,现有智能车辆的局部轨迹规划方法存在规划耗时长、曲率不连续、安全性不足等问题.针对该类问题,提出一种面向泊车场景的智能车辆轨迹规划方法.该方法通过改进混合A^(*)算法的... 详细信息

局部轨迹规划是自主代客泊车系统的关键技术之一,在该场景下,现有智能车辆的局部轨迹规划方法存在规划耗时长、曲率不连续、安全性不足等问题.针对该类问题,提出一种面向泊车场景的智能车辆轨迹规划方法.该方法通过改进混合A^(*)算法的解析扩展以及引入风险函数,提升了初始路径搜索的实时性和安全性.进一步,结合初始路径以及二次规划方法实现路径平滑和速度规划,最终完成轨迹生成.仿真实验表明,所提方法能够提升智能车辆轨迹规划实时性、平滑性以及安全性,并且在实车试验上验证所提方法在实际泊车场景的可行性.

关键词：智能车辆泊车场景轨迹规划混合A^(*)算法二次规划

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中草药免疫调节剂及抗肿瘤作用研究进展

职业与健康 2005年第10期21卷 1454-1456页

作者：何跃生天津市医药科学研究所 300020

中药免疫调节剂绝大多数是免疫促进剂,而其有效成分为多糖(polysaccharides)是由醛糖或酮糖通过糖苷相连接的一类天然大分子聚合物,它在自然界中来源广泛。上世纪50年代,由于多糖显著免疫活性的发现,使得多糖成为中药药理学尤其是免疫... 详细信息

中药免疫调节剂绝大多数是免疫促进剂,而其有效成分为多糖(polysaccharides)是由醛糖或酮糖通过糖苷相连接的一类天然大分子聚合物,它在自然界中来源广泛。上世纪50年代,由于多糖显著免疫活性的发现,使得多糖成为中药药理学尤其是免疫药理学研究的热点,中药多糖作为非特异性的免疫调节剂能在多条途径,多个层面对免疫系统发挥作用:诱生多种细胞因子,促进干扰素,白细胞介素等的生成;激活巨噬细胞,NK细胞和T、B淋巴细胞;激活网状内皮系统和补体系统;促进抗体产生等对免疫系统发挥多方面的调节作用。该文阐述了中药多糖免疫调节和抗肿瘤等功能。

关键词：中药多糖免疫调节抗肿瘤

HPLC法测定阿魏酸钠在Beagle犬体内血浆浓度及药动学研究

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天津医药 2007年第9期35卷 687-689页

作者：何跃生袁玲曲树明天津市医药科学研究所 300020

目的:建立测定血浆中阿魏酸钠浓度的HPLC法,并用于阿魏酸钠片剂在Beagle犬体内的药代动力学研究。方法:色谱柱为Diamonsil(TM)C18柱,250mm×4.6mm,5μm,流动相为乙腈-水-冰乙酸(25∶74.2∶0.8),流速为1.0mL/min,检测波长为320nm。以替... 详细信息

目的:建立测定血浆中阿魏酸钠浓度的HPLC法,并用于阿魏酸钠片剂在Beagle犬体内的药代动力学研究。方法:色谱柱为Diamonsil(TM)C18柱,250mm×4.6mm,5μm,流动相为乙腈-水-冰乙酸(25∶74.2∶0.8),流速为1.0mL/min,检测波长为320nm。以替硝唑为内标,用乙腈处理血浆样品,震荡离心分离上清液进样。结果:标准曲线线性范围0.025～1.80mg/L,r=0.9995。阿魏酸钠平均回收率99.6%,最低检测浓度为5.25μg/L,日内、日间RSD<5.3%。阿魏酸钠片剂在Beagle犬体内的血药浓度-时间过程符合一房室模型,T1/2(ka)为10.88min,T1/2(ke)为29.78min。结论:HPLC法方法简便、快速、重现性好,适用于阿魏酸钠血药浓度测定及药代动力学研究。

关键词：阿魏酸钠色谱法高效液相药代动力学狗血药浓度

Recent progress in constructing fluorinated solid-electrolyte interphases for stable lithium metal anodes

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 270-291页

作者： Di Zhang Pengfei Lv Wei Qin Xin he Yuanhua he Civil Aircraft Fire Science and Safety Engineering Key Laboratory of Sichuan Province College of Civil Aviation Safety EngineeringCivil Aviation Flight University of ChinaGuanghan 618307China School of Chemical Engineering Sichuan UniversityChengdu 610065China

Lithium metal batteries(LMBs)are emerging as a promising energy storage solution owing to their high energy density and specific ***,the non-uniform plating of lithium and the potential rupture of the solid-electrolyte interphase(SEI)during extended cycling use may result in dendrite growth,which can penetrate the separator and pose significant short-circuit *** a stable SEI is essential for the long-term operation of the ***-rich SEI has garnered significant attention for its ability to effectively passivate electrodes,regulate lithium deposition,and inhibit electrolyte *** the structural components and preparation methods of existing fluorinated SEI is crucial for optimizing lithium metal anode *** paper reviews the research on optimizing LiF passivation interfaces to protect lithium metal *** focuses on four types of compositions in fluorinated SEI that work synergistically to enhance SEI *** instance,combining compounds with LiF can further enhance the mechanical strength and ionic conductivity of the *** metals with LiF significantly improves electrochemical performance at the SEI/anode interface,with a necessary focus on reducing electron tunneling ***,incorporating polymers with LiF offers balanced improvements in interfacial toughness and ionic conductivity,though maintaining structural stability over long cycles remains a critical area for future *** alloys combined with LiF increase surface energy and lithium affinity,challenges such as dendrite growth and volume expansion *** summary,this paper emphasizes the crucial role of interfacial structures in LMBs and offers comprehensive guidance for future design and development efforts in battery technology.

关键词： LiF lithium metal anodes solid-electrolyte interphase interface cycling stability

Constraints on holographic QCD phase transitions from PTA observations

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 71-78页

作者： Song he Li Li Sai Wang Shao-Jiang Wang Center for Theoretical Physics and College of Physics Jilin University School of Physical Science and Technology Ningbo University Max Planck Institute for Gravitational Physics (Albert Einstein Institute) CAS Key Laboratory of Theoretical Physics Institute of Theoretical Physics Chinese Academy of Sciences School of Fundamental Physics and Mathematical Sciences Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of Sciences (UCAS) School of Physical Sciences University of Chinese Academy of Sciences (UCAS) Theoretical Physics Division Institute of High Energy Physics Chinese Academy of Sciences

The underlying physics of QCD phase transition in the early Universe remains largely unknown due to its strong-coupling nature during the quark-gluon plasma/hadron gas transition, yet a holographic model has been proposed to quantitatively fit the lattice QCD data while with its duration of the first-order phase transition(FoPT) left undetermined. At specific baryon chemical potential, the first-order QCD phase transition agrees with the observational constraint of baryon asymmetry. It, therefore, provides a scenario for phase transition gravitational waves(GWs) within the standard model of particle physics. If these background GWs could contribute dominantly to the recently claimed common-spectrum red noise from pulsar timing array(PTA) observations, the duration of this FoPT can be well constrained, and the associated primordial black holes are still allowed by current observations.

关键词： pulsar timing array QCD phase transition gravitational waves primordial black holes

Impact of ocean data assimilation on the seasonal forecast of the 2014/15 marine heatwave in the Northeast Pacific Ocean

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Atmospheric and Oceanic Science Letters 2025年第1期18卷 24-31页

作者： Tiantian Tang Jiaying he Huihang Sun Jingjia Luo Institute for Climate and Application Research(ICAR)/Key Laboratory of Meteorological Disaster Nanjing University of Information Science and TechnologyNanjingChina

A remarkable marine heatwave,known as the“Blob”,occurred in the Northeast Pacific Ocean from late 2013 to early 2016,which displayed strong warm anomalies extending from the surface to a depth of 300 *** study employed two assimilation schemes based on the global Climate Forecast System of Nanjing University of Information Science(NUIST-CFS 1.0)to investigate the impact of ocean data assimilation on the seasonal prediction of this extreme marine *** sea surface temperature(SST)nudging scheme assimilates SST only,while the deterministic ensemble Kalman filter(EnKF)scheme assimilates observations from the surface to the deep *** latter notably improves the forecasting skill for subsurface temperature anomalies,especially at the depth of 100-300 m(the lower layer),outperforming the SST nudging *** excels in predicting both horizontal and vertical heat transport in the lower layer,contributing to improved forecasts of the lower-layer warming during the *** improvements stem from the assimilation of subsurface observational data,which are important in predicting the upper-ocean *** results suggest that assimilating ocean data with the EnKF scheme significantly enhances the accuracy in predicting subsurface temperature anomalies during the Blob and offers better understanding of its underlying mechanisms.

关键词： Seasonal forecast Ocean data assimilation Marine heatwave Subsurface temperature