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Acupuncture at Back-Shu point improves insomnia by reducing inflammation and inhibiting the ERK/NF-κB signaling pathway 被引量:1
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作者 Ming-Ming Zhang Jing-Wei Zhao +2 位作者 Zhi-Qiang Li Jing Shao Xi-Yan Gao 《World Journal of Psychiatry》 SCIE 2023年第6期340-350,共11页
BACKGROUND Insomnia is a disease where individuals cannot maintain a steady and stable sleep state or fail to fall asleep.Western medicine mainly uses sedatives and hypnotic drugs to treat insomnia,and long-term use i... BACKGROUND Insomnia is a disease where individuals cannot maintain a steady and stable sleep state or fail to fall asleep.Western medicine mainly uses sedatives and hypnotic drugs to treat insomnia,and long-term use is prone to drug resistance and other adverse reactions.Acupuncture has a good curative effect and unique advantages in the treatment of insomnia.AIM To explore the molecular mechanism of acupuncture at Back-Shu point for the treatment of insomnia.METHODS We first prepared a rat model of insomnia,and then carried out acupuncture for 7 consecutive days.After treatment,the sleep time and general behavior of the rats were determined.The Morris water maze test was used to assess the learning ability and spatial memory ability of the rats.The expression levels of inflammatory cytokines in serum and the hippocampus were detected by ELISA.qRTPCR was used to detect the mRNA expression changes in the ERK/NF-κB signaling pathway.Western blot and immunohistochemistry were carried out to evaluate the protein expression levels of RAF-1,MEK-2,ERK1/2 and NF-κB.RESULTS Acupuncture can prolong sleep duration,and improve mental state,activity,diet volume,learning ability and spatial memory.In addition,acupuncture increased the release of 1L-1β,1L-6 and TNF-αin serum and the hippocampus and inhibited the mRNA and protein expression of the ERK/NF-κB signaling pathway.CONCLUSION These findings suggest that acupuncture at Back-Shu point can inhibit the ERK/NF-κB signaling pathway and treat insomnia by increasing the release of inflammatory cytokines in the hippocampus. 展开更多
关键词 ERK/NF-κB signaling pathway ACUPUNCTURE INSOMNIA INFLAMMATION Acupuncture at back-shu point Traditional Chinese medicine
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Effect of intradermal needle at five-zang Back-Shu points on treatment of chronic fatigue syndrome
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作者 Shi-Meng Li Jie Wang +3 位作者 Lu-Fan Xu Xian-Cheng Zheng Zhi-Yuan Hui Jun Wang 《Journal of Hainan Medical University》 2022年第1期30-35,共6页
Objective:To observe the effect of intradermal needle therapy on back-shu points of five zang organs in treating chronic fatigue syndrome(CFS)and provide evidence for the usage of unilateral back-shu point.Methods:Pat... Objective:To observe the effect of intradermal needle therapy on back-shu points of five zang organs in treating chronic fatigue syndrome(CFS)and provide evidence for the usage of unilateral back-shu point.Methods:Patients were randomly divided into bilateral back-shu point group,unilateral back-shu point group and non-acupoint group,remove shedding cases,each group remaining 30 patients.In bilateral back-shu point group,both sides of back-shu points of five zang organs were selected.In unilateral back-shu point group,only one side was selected,left or right alternately.The location where non-acupoint group inserted by intradermal needles were outward from the back-shu points,left or right alternately.Fatigue Scale-14(FS-14)was used to evaluate the fatigue level and the scores’improvement of physical fatigue and mental fatigue revealed the therapeutic effect on body constituents and spirits of CFS patient.Results:After the 8-week intradermal needle therapy,the total effective rate was 83.33%in the bilateral back-shu point group,which was 76.67%in the unilateral back-shu point group and 50.00%in the non-acupoint group.The curative effects of the two groups whose back-shu points of five zang organs were inserted by intradermal needles were better than the non-acupoint group(P<0.05).There was no significant difference in clinical efficacy between the bilateral back-shu point group and the unilateral back-shu point group(P>0.05).There were statistical differences in FS-14 questionnaires including total,physical and mental scores between before and after the treatment in both the two back-shu point groups(P<0.05).Only the scores of total and physical fatigue in decreased in non-acupoint group(P<0.05),which means it couldn’t help to alleviate mental fatigue statistically(P>0.05).Conclusions:(1)The intradermal needle therapy on back-shu points of five zang organs for CFS has a satisfying clinical efficacy in curing tiredness.It can help to reduce both physical and mental fatigue for the patients.Hence,it can regulate both body constituents and spirits simultaneously.(2)Needling the unilateral acupoints can get similar clinical efficacy to the bilateral points.It reveals that we can cut cost by reducing the consumption of the amount of intradermal needles used on one side.(3)Both the groups of back-shu points get better clinical efficacy than the non-acupoint group dramatically.The reason of why the intradermal needle can treat CFS maybe that back-shu points of five zang organs can regulate the functions of five zang organs characteristically. 展开更多
关键词 back-shu point Chronic fatigue syndrome Intradermal needle Simultaneous regulation on both body constituents and spirits Clinical trial
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CLINICAL OBSERVATION ON TREATMENT OF ACUTE BRONCHITIS PRIMARILY WITH PRICKING-CUPPING ON BACK-SHU POINTS
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作者 徐蔚东 张永娟 +2 位作者 杨洁 陈晓香 刘永香 《World Journal of Acupuncture-Moxibustion》 2006年第2期15-18,共4页
To observe the clinical effect of treatment of acute bronchitis primarily with prickingcupping method on Back-shu points. Methods. The patients of acute bronchitis were randomly divided into 2 groups. In the observati... To observe the clinical effect of treatment of acute bronchitis primarily with prickingcupping method on Back-shu points. Methods. The patients of acute bronchitis were randomly divided into 2 groups. In the observation group, there were 36 cases, who were treated with the integrated traditional Chinese and western medicine, primarily the pricking-cupping method on Back-shu points; while in the control group, there were 29 cases who were given the conventinal treatment of western medicine. All the 2 groups were treated for 7 days as one treating course. Results: The total effective rate of the observation group was 97.2% while that of the control group was 82,8%, so there is a significant difference between them. On the first and third days the clinical manifestations were more satisfactorily improved in the treatment group than in the control group (P 〈 0.01) and on the fifth and seventh days, the comparison showed no significant difference (P〉0.05). Conclusion: The treatment of acute bronchitis by means of the integrated traditional Chinese and western medicine primarily with pricking-cupping method on Back-shu points is of marked therapeutic effect, simple manipulation, and little untoward effects, thus claiming the unique advantage. 展开更多
关键词 Acute bronchitis Integrated traditional Chinese and western medicine Pricking-cupping method back-shu point
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Treatment of Urticaria with Cupping at Back-Shu Points——A Report of 40 Cases
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作者 李丽梅 丁杰 周永生 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 2001年第1期37-38,共2页
Urticaria is a common and frequently encountered disease, which is mainly manifested by extreme pruritus and lumpish eruption of the skin. Acute urticaria with a short disease course can be cured, while the chronic on... Urticaria is a common and frequently encountered disease, which is mainly manifested by extreme pruritus and lumpish eruption of the skin. Acute urticaria with a short disease course can be cured, while the chronic one with repeated attacks is a lingering disorder. In the past few years, 40 cases of urticaria were treated by cupping at the back-shu points of the five zang-organs and Geshu (BL 17). Another 20 cases in the control group were treated with Fang Feng Tong Sheng Wan (防风通圣丸Miraculous Pills of Ledebouriella) and chlorpheniramine maleate. The therapeutic effect in the treatment group was significantly superior to that in the control group. The results are reported as follows. 展开更多
关键词 Acupuncture points ADOLESCENT ADULT FEMALE Humans MALE Middle Aged URTICARIA
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基于轻量化PointNet网络的林果园喷雾作业靶标实时识别方法 被引量:1
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作者 刘慧 杜志鹏 +2 位作者 杨锋 张钰 沈跃 《农业工程学报》 EI CAS CSCD 北大核心 2024年第8期144-151,共8页
为了进一步提高喷雾机器人靶标检测的精准性、实时性和应用部署的实用性,该研究提出一种基于轻量化PointNet网络的林果园喷雾作业靶标实时识别方法。首先通过区域提取降采样、地面分割和改进DBSCAN聚类等点云预处理方法提取原始点云中... 为了进一步提高喷雾机器人靶标检测的精准性、实时性和应用部署的实用性,该研究提出一种基于轻量化PointNet网络的林果园喷雾作业靶标实时识别方法。首先通过区域提取降采样、地面分割和改进DBSCAN聚类等点云预处理方法提取原始点云中的靶标;然后通过移动最小二乘上采样将靶标点云转化为满足点云识别网络输入要求的点云数据;最终通过在PointNet网络中引入残差模块和改进循环剪枝算法轻量化PointNet网络,完成林果树靶标的实时识别。试验结果表明,在ModelNet40数据集上,轻量化PointNet网络可达89.7%的准确率;在实际苗圃环境的试验中,该研究方法对靶标的识别准确率可达92.49%,同时误识率与拒识率分别为13.4%和6.47%,相较PointNet网络识别准确率提升了4.38个百分点,误识率和拒识率分别降低了7.2和4.07个百分点;轻量化PointNet网络识别准确率仅比PointNet++网络低1.14个百分点,误识率和拒识率分别高了0.9和1.12个百分点。但是轻量化PointNet网络的模型参数量较PointNet网络和PointNet++网络的模型参数量显著减少,仅为PointNet网络的11.5%,PointNet++网络的27.02%;运算量相较PointNet网络、PointNet++网络分别减少13.3和76.79个百分点。该研究提出的轻量化PointNet网络具有较高的实时性、精确性和鲁棒性,能够满足林果园喷雾作业的靶标识别需求,可为林果园喷雾作业靶标实时识别提供参考。 展开更多
关键词 喷雾 机器人 林果园 点云预处理 轻量化pointNet网络 循环剪枝
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基于PointNet++的邻域特征增强点云语义分割方法
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作者 李松 张安思 +1 位作者 伍婕 张保 《激光杂志》 CAS 北大核心 2024年第7期174-179,共6页
随着智能驾驶、机器人导航等以点云为基础的应用蓬勃发展,点云语义分割逐渐成为研究热点。然而,现有的点云语义分割方法存在局部特征提取不充分、特征融合不完整的缺陷。针对这些不足,提出了对应的解决方案。对于局部特征提取不充分的现... 随着智能驾驶、机器人导航等以点云为基础的应用蓬勃发展,点云语义分割逐渐成为研究热点。然而,现有的点云语义分割方法存在局部特征提取不充分、特征融合不完整的缺陷。针对这些不足,提出了对应的解决方案。对于局部特征提取不充分的现象,通过嵌入邻域点的坐标、方向、距离等相关信息去关联邻域点的显式特征。对于特征融合不完整的现象,提出了一种最大池化与自注意力池化相结合的混合池化方法。网络架构基于PointNet++,并结合提出的局部特征提取和融合方法,在S3DIS数据集上的实验结果表明,与基线方法PointNet++相比,各评价指标都有不同程度的提高,证实了新方法的有效性和优越性。 展开更多
关键词 三维点云 语义分割 特征提取 深度学习
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Clinical research on insomnia treated by acupuncture at back-shu points 被引量:3
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作者 高希言 徐翠香 +4 位作者 陈新旺 王培育 高崚 任珊 马巧琳 《World Journal of Acupuncture-Moxibustion》 2014年第2期36-41,共6页
Objective To observe the clinical therapeutic effect on insomnia treated with acupuncture at back-shu points. Methods Sixty-four cases of insomnia were selected and divided randomly into a back-shu points group (grou... Objective To observe the clinical therapeutic effect on insomnia treated with acupuncture at back-shu points. Methods Sixty-four cases of insomnia were selected and divided randomly into a back-shu points group (group A) and a conventional acupoints group (group B) by a computer generated allocation list, 32 cases in each one. In the trial group, acupuncture was applied at xinshu (心俞 15), Ganshu (刊俞 18), Pishu (脾俞 BL 20) and Geshu (膈俞 BL 17). In the control group, acupuncture was applied conventionally to Neiguan (内关 PC 6), Shenmen (神门 HT 7), Sanyinjiao (三阴交 SP 6), Baihui (百会 GV 20) and Sishencong (四神聪 EX-HN 2). Ten treatments made a session. The efficacy was analyzed statistically after 3 sessions of treatment. Results There were significant differences between the two groups in the relief of sleep disorders after the treatment (P〈0.O2). The improvement in sleep efficiency was different significantly (P〈0.05). The difference in sleep difficulty was significant in Chinese medicine (TCM) symptom score (P〈0.05). Conclusion The clinical efficacy is achieved by either acupuncture at back-shu points or by acupuncture at conventional acupoints. The improvements of sleep efficiency and sleep disorder scores in PSO.I, and sleep difficulty in TCM as well as the long-term efficacy are superior in group A as compared with those in group B. 展开更多
关键词 INSOMNIA acupuncture therapy back-shu points BL 15 BL 18 BL 20 BL 17 randomized controlled trial
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基于Point Transformer v2的点云枝叶分离方法研究
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作者 马津 陈一平 +3 位作者 韩汀 王朝磊 张小海 张吴明 《航天返回与遥感》 CSCD 北大核心 2024年第3期62-72,共11页
准确高效的点云枝叶分离对精确计算森林树木的垂直参数至关重要。然而,当前的研究方法计算成本高,且依赖先验知识导致泛化能力不足。针对以上问题,文章提出利用基于点特征的Transformer网络进行自动化的森林场景三维点云的枝叶分离研究... 准确高效的点云枝叶分离对精确计算森林树木的垂直参数至关重要。然而,当前的研究方法计算成本高,且依赖先验知识导致泛化能力不足。针对以上问题,文章提出利用基于点特征的Transformer网络进行自动化的森林场景三维点云的枝叶分离研究。该方法使用Point Transformer v2网络,首先利用网格编码模块提取可学习的局部结构关系,保留点云的几何拓扑结构;其次使用分组注意力实现多通道联合学习,降低特征的冗余度,提高计算的效率;最后构建了基于点的Transformer网络实现高精度森林树木三维点云语义分割,降低了对于先验知识的需求。使用地基激光扫描仪获取的加拿大和芬兰7个不同树种样地的三维点云数据,进行枝叶分离实验和精度评价。实验结果表明,网络整体精度(OA)为94.42%,mIoU为78.89%,能够适应不同树种、不同点云密度的森林场景的枝叶分离。 展开更多
关键词 三维点云 深度学习 枝叶分离 point TRANSFORMER V2
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Point Cloud Classification Using Content-Based Transformer via Clustering in Feature Space 被引量:2
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作者 Yahui Liu Bin Tian +2 位作者 Yisheng Lv Lingxi Li Fei-Yue Wang 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第1期231-239,共9页
Recently, there have been some attempts of Transformer in 3D point cloud classification. In order to reduce computations, most existing methods focus on local spatial attention,but ignore their content and fail to est... Recently, there have been some attempts of Transformer in 3D point cloud classification. In order to reduce computations, most existing methods focus on local spatial attention,but ignore their content and fail to establish relationships between distant but relevant points. To overcome the limitation of local spatial attention, we propose a point content-based Transformer architecture, called PointConT for short. It exploits the locality of points in the feature space(content-based), which clusters the sampled points with similar features into the same class and computes the self-attention within each class, thus enabling an effective trade-off between capturing long-range dependencies and computational complexity. We further introduce an inception feature aggregator for point cloud classification, which uses parallel structures to aggregate high-frequency and low-frequency information in each branch separately. Extensive experiments show that our PointConT model achieves a remarkable performance on point cloud shape classification. Especially, our method exhibits 90.3% Top-1 accuracy on the hardest setting of ScanObjectN N. Source code of this paper is available at https://github.com/yahuiliu99/PointC onT. 展开更多
关键词 Content-based Transformer deep learning feature aggregator local attention point cloud classification
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Material point method simulation of hydro-mechanical behaviour in twophase porous geomaterials: A state-of-the-art review 被引量:2
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作者 Xiangcou Zheng Shuying Wang +1 位作者 Feng Yang Junsheng Yang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第6期2341-2350,共10页
The material point method(MPM)has been gaining increasing popularity as an appropriate approach to the solution of coupled hydro-mechanical problems involving large deformation.In this paper,we survey the current stat... The material point method(MPM)has been gaining increasing popularity as an appropriate approach to the solution of coupled hydro-mechanical problems involving large deformation.In this paper,we survey the current state-of-the-art in the MPM simulation of hydro-mechanical behaviour in two-phase porous geomaterials.The review covers the recent advances and developments in the MPM and their extensions to capture the coupled hydro-mechanical problems involving large deformations.The focus of this review is aiming at providing a clear picture of what has or has not been developed or implemented for simulating two-phase coupled large deformation problems,which will provide some direct reference for both practitioners and researchers. 展开更多
关键词 Coupled problems Hydro-mechanical behaviour Large deformation Material point Method(MPM)
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Two-Staged Method for Ice Channel Identification Based on Image Segmentation and Corner Point Regression 被引量:1
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作者 DONG Wen-bo ZHOU Li +2 位作者 DING Shi-feng WANG Ai-ming CAI Jin-yan 《China Ocean Engineering》 SCIE EI CSCD 2024年第2期313-325,共13页
Identification of the ice channel is the basic technology for developing intelligent ships in ice-covered waters,which is important to ensure the safety and economy of navigation.In the Arctic,merchant ships with low ... Identification of the ice channel is the basic technology for developing intelligent ships in ice-covered waters,which is important to ensure the safety and economy of navigation.In the Arctic,merchant ships with low ice class often navigate in channels opened up by icebreakers.Navigation in the ice channel often depends on good maneuverability skills and abundant experience from the captain to a large extent.The ship may get stuck if steered into ice fields off the channel.Under this circumstance,it is very important to study how to identify the boundary lines of ice channels with a reliable method.In this paper,a two-staged ice channel identification method is developed based on image segmentation and corner point regression.The first stage employs the image segmentation method to extract channel regions.In the second stage,an intelligent corner regression network is proposed to extract the channel boundary lines from the channel region.A non-intelligent angle-based filtering and clustering method is proposed and compared with corner point regression network.The training and evaluation of the segmentation method and corner regression network are carried out on the synthetic and real ice channel dataset.The evaluation results show that the accuracy of the method using the corner point regression network in the second stage is achieved as high as 73.33%on the synthetic ice channel dataset and 70.66%on the real ice channel dataset,and the processing speed can reach up to 14.58frames per second. 展开更多
关键词 ice channel ship navigation IDENTIFICATION image segmentation corner point regression
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Automatic Extraction Method of 3D Feature Guidelines for Complex Cultural Relic Surfaces Based on Point Cloud 被引量:1
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作者 GENG Yuxin ZHONG Ruofei +1 位作者 HUANG Yuqin SUN Haili 《Journal of Geodesy and Geoinformation Science》 CSCD 2024年第1期16-41,共26页
Cultural relics line graphic serves as a crucial form of traditional artifact information documentation,which is a simple and intuitive product with low cost of displaying compared with 3D models.Dimensionality reduct... Cultural relics line graphic serves as a crucial form of traditional artifact information documentation,which is a simple and intuitive product with low cost of displaying compared with 3D models.Dimensionality reduction is undoubtedly necessary for line drawings.However,most existing methods for artifact drawing rely on the principles of orthographic projection that always cannot avoid angle occlusion and data overlapping while the surface of cultural relics is complex.Therefore,conformal mapping was introduced as a dimensionality reduction way to compensate for the limitation of orthographic projection.Based on the given criteria for assessing surface complexity,this paper proposed a three-dimensional feature guideline extraction method for complex cultural relic surfaces.A 2D and 3D combined factor that measured the importance of points on describing surface features,vertex weight,was designed.Then the selection threshold for feature guideline extraction was determined based on the differences between vertex weight and shape index distributions.The feasibility and stability were verified through experiments conducted on real cultural relic surface data.Results demonstrated the ability of the method to address the challenges associated with the automatic generation of line drawings for complex surfaces.The extraction method and the obtained results will be useful for line graphic drawing,displaying and propaganda of cultural relics. 展开更多
关键词 point cloud conformal parameterization vertex weight surface mesh cultural relics feature extraction
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基于改进PointNet++的输电线路关键部位点云语义分割研究
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作者 杨文杰 裴少通 +3 位作者 刘云鹏 胡晨龙 杨瑞 张行远 《高电压技术》 EI CAS CSCD 北大核心 2024年第5期1943-1953,I0009,共12页
输电线路的关键部位包括塔身、导线、绝缘子、避雷线以及引流线,无人机精细化导航的首要任务是构造输电线路的点云地图并从中分割出上述部位。为解决现有算法在输电线路的绝缘子、引流线等精细结构分割时精度低的问题,通过改进PointNet+... 输电线路的关键部位包括塔身、导线、绝缘子、避雷线以及引流线,无人机精细化导航的首要任务是构造输电线路的点云地图并从中分割出上述部位。为解决现有算法在输电线路的绝缘子、引流线等精细结构分割时精度低的问题,通过改进PointNet++算法,提出了一种面向输电线路精细结构的点云分割方法。首先,基于无人机机载激光雷达在现场采集的点云数据,构造了输电线路点云分割数据集;其次,通过对比实验,筛选出在本输电线路场景下合理的数据增强方法,并对数据集进行了数据增强;最后,将自注意力机制以及倒置残差结构和PointNet++相结合,设计了输电线路关键部位点云语义分割算法。实验结果表明:该改进PointNet++算法在全场景输电线路现场点云数据作为输入的前提下,首次实现了对引流线、绝缘子等输电线路中精细结构和导线、杆塔塔身以及输电线路无关背景点的同时分割,平均交并比(mean intersection over union,mIoU)达80.79%,所有类别分割的平均F_(1)值(F1 score)达88.99%。 展开更多
关键词 点云深度学习 点云语义分割 数据增强 自注意力 倒置残差
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基于PointNet++进行附属设施语义分割的隧道收敛变形分析
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作者 卞政 石波 +3 位作者 吴凡 王静 赵凯 杨兴宜 《铁道科学与工程学报》 EI CAS CSCD 北大核心 2024年第11期4827-4839,共13页
随着城市轨道交通日趋广泛,隧道结构变形引起的地铁安全事故凸显,亟需对运营期隧道进行变形检测。隧道衬砌作为隧道变形分析的研究对象,衬砌内表面存在的大量附属设施影响隧道收敛变形分析精度。为了提高变形分析精度,解决点云处理环节... 随着城市轨道交通日趋广泛,隧道结构变形引起的地铁安全事故凸显,亟需对运营期隧道进行变形检测。隧道衬砌作为隧道变形分析的研究对象,衬砌内表面存在的大量附属设施影响隧道收敛变形分析精度。为了提高变形分析精度,解决点云处理环节中存在的自动化程度低的问题,提出基于PointNet++点云语义分割的隧道收敛变形分析方法。首先利用深度学习方法进行点云语义分割,对隧道衬砌附属设施进行自动滤除。然后对隧道衬砌进行断面提取,利用随机抽样一致性算法(Random Sample Consensus,RANSAC)对隧道断面点云进行采样,分析隧道收敛变形程度,从Z+F PROFILER 9012A激光断面扫描仪获取山东省济南市地铁盾构隧道点云实测数据上并进行应用。研究结果表明:所提出的处理方法可以有效地将大规模隧道衬砌与连接紧密的附属设施分离出来,隧道附属设施总体分类精度达到96%,滤波结果较好地保留了隧道衬砌原始形态特征。在对隧道整体和局部收敛变形分析的重复性验证中,测试区间内隧道整体变形精度往返测长半轴平均偏差为1.04 mm,短半轴平均偏差为0.9 mm,测试区间内隧道局部收敛变形往返测标准差最小为0.773 mm,最大为0.938 mm,可以满足隧道收敛变形分析的精度需求。研究结果可以有效提升处理大规模隧道数据的自动化程度,具有良好的有效性与可靠性,对运营期地铁隧道收敛变形检测或监测有较好的实践应用意义。 展开更多
关键词 轨道交通隧道 激光点云 收敛变形分析 点云深度学习 随机抽样一致性
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Coexistence of Dirac and Weyl points in non-centrosymmetric semimetal NbIrTe_(4)
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作者 刘清馨 付阳 +4 位作者 丁鹏飞 马欢 郭朋杰 雷和畅 王善才 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期146-151,共6页
Using angle-resolved photoemission spectroscopy and density functional theory calculations methods,we investigate the electronic structures and topological properties of ternary tellurides NbIrTe_(4),a candidate for t... Using angle-resolved photoemission spectroscopy and density functional theory calculations methods,we investigate the electronic structures and topological properties of ternary tellurides NbIrTe_(4),a candidate for type-II Weyl semimetal.We demonstrate the presence of several Fermi arcs connecting their corresponding Weyl points on both termination surfaces of the topological material.Our analysis reveals the existence of Dirac points,in addition to Weyl points,giving both theoretical and experimental evidences of the coexistence of Dirac and Weyl points in a single material.These findings not only confirm NbIrTe_(4) as a unique topological semimetal but also open avenues for exploring novel electronic devices based on its coexisting Dirac and Weyl fermions. 展开更多
关键词 Fermi arc Weyl point Dirac point angle-resolved photoemission spectroscopy
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基于知识蒸馏和定位引导的Pointpillars点云检测网络 被引量:1
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作者 赵晶 李少博 +3 位作者 郭杰龙 俞辉 张剑锋 李杰 《液晶与显示》 CSCD 北大核心 2024年第1期79-88,共10页
激光雷达数据由于其几何特性,被广泛应用于三维目标检测任务中。由于点云数据的稀疏性和不规则性,难以实现特征提取的质量和推理速度间的平衡。本文提出一种基于体柱特征编码的三维目标检测算法,以Pointpillars网络为基础,设计Teacher-S... 激光雷达数据由于其几何特性,被广泛应用于三维目标检测任务中。由于点云数据的稀疏性和不规则性,难以实现特征提取的质量和推理速度间的平衡。本文提出一种基于体柱特征编码的三维目标检测算法,以Pointpillars网络为基础,设计Teacher-Student模型框架对回归框尺度进行蒸馏,增加蒸馏损失,优化训练网络模型,提升特征提取的质量。为进一步提高模型检测效果,设计定位引导分类项,增加分类预测和回归预测之间的相关性,提高物体识别准确率。本网络所做改进没有引入额外的网络嵌入。算法在KITTI数据集上的实验结果表明,相比于基准网络,在三维模式下的平均精度值从60.65%提升到了64.69%,鸟瞰图模式下的平均精度值从67.74%提升到70.24%。模型推理速度为45 FPS,在提升检测精度的同时满足了实时性要求。 展开更多
关键词 激光点云 三维目标检测 知识蒸馏 分类置信度
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PCT和PointMLP融合的三维点云分类算法研究
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作者 赵晓柯 汤勃 +1 位作者 孙伟 朱发汛 《组合机床与自动化加工技术》 北大核心 2024年第10期68-71,共4页
为了提高三维点云数据的分类准确率,对注意力机制的PCT与残差点MLP的PointMLP的融合算法进行研究。首先,加入几何仿射模块对输入点云进行正态分布以解决点云的密度不均匀和几何结构不确定性;其次,在编码模块首先使用注意力机制对上层特... 为了提高三维点云数据的分类准确率,对注意力机制的PCT与残差点MLP的PointMLP的融合算法进行研究。首先,加入几何仿射模块对输入点云进行正态分布以解决点云的密度不均匀和几何结构不确定性;其次,在编码模块首先使用注意力机制对上层特征进行全局表达,之后加入残差点MLP模块对注意力模块的输出特征进行深度特征表示以充分提取点云特征;最后是分类模块,完成下游点云分类任务。实验结果表明,改进后的算法在ModelNet40数据集上的分类准确率达到95.6%,相比PCT模型准确率提高了2.4%,且对点云数量的变化具有鲁棒性。 展开更多
关键词 三维点云 注意力 残差点MLP 点云分类
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Enhanced Mechanism for Link Failure Rerouting in Software-Defined Exchange Point Networks
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作者 Abdijalil Abdullahi Selvakumar Manickam 《Computers, Materials & Continua》 SCIE EI 2024年第9期4361-4385,共25页
Internet Exchange Point(IXP)is a system that increases network bandwidth performance.Internet exchange points facilitate interconnection among network providers,including Internet Service Providers(ISPs)andContent Del... Internet Exchange Point(IXP)is a system that increases network bandwidth performance.Internet exchange points facilitate interconnection among network providers,including Internet Service Providers(ISPs)andContent Delivery Providers(CDNs).To improve service management,Internet exchange point providers have adopted the Software Defined Network(SDN)paradigm.This implementation is known as a Software-Defined Exchange Point(SDX).It improves network providers’operations and management.However,performance issues still exist,particularly with multi-hop topologies.These issues include switch memory costs,packet processing latency,and link failure recovery delays.The paper proposes Enhanced Link Failure Rerouting(ELFR),an improved mechanism for rerouting link failures in software-defined exchange point networks.The proposed mechanism aims to minimize packet processing time for fast link failure recovery and enhance path calculation efficiency while reducing switch storage overhead by exploiting the Programming Protocol-independent Packet Processors(P4)features.The paper presents the proposed mechanisms’efficiency by utilizing advanced algorithms and demonstrating improved performance in packet processing speed,path calculation effectiveness,and switch storage management compared to current mechanisms.The proposed mechanism shows significant improvements,leading to a 37.5%decrease in Recovery Time(RT)and a 33.33%decrease in both Calculation Time(CT)and Computational Overhead(CO)when compared to current mechanisms.The study highlights the effectiveness and resource efficiency of the proposed mechanism in effectively resolving crucial issues inmulti-hop software-defined exchange point networks. 展开更多
关键词 Link failure recovery Internet exchange point software-defined exchange point software-defined network multihop topologies
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Diagnosis of indirectly driven double shell targets with point-projection hard x-ray radiography
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作者 Chao Tian Minghai Yu +17 位作者 Lianqiang Shan Fengjuan Wu Bi Bi Qiangqiang Zhang Yuchi Wu Tiankui Zhang Feng Zhang Dongxiao Liu Weiwu Wang Zongqiang Yuan Siqian Yang Lei Yang Zhigang Deng Jian Teng Weimin Zhou Zongqing Zhao Yuqiu Gu Baohan Zhang 《Matter and Radiation at Extremes》 SCIE EI CSCD 2024年第2期50-62,共13页
We present an application of short-pulse laser-generated hard x rays for the diagnosis of indirectly driven double shell targets. Coneinserted double shell targets were imploded through an indirect drive approach on t... We present an application of short-pulse laser-generated hard x rays for the diagnosis of indirectly driven double shell targets. Coneinserted double shell targets were imploded through an indirect drive approach on the upgraded SG-II laser facility. Then, based on thepoint-projection hard x-ray radiography technique, time-resolved radiography of the double shell targets, including that of their near-peakcompression, were obtained. The backlighter source was created by the interactions of a high-intensity short pulsed laser with a metalmicrowire target. Images of the target near peak compression were obtained with an Au microwire. In addition, radiation hydrodynamicsimulations were performed, and the target evolution obtained agrees well with the experimental results. Using the radiographic images, arealdensities of the targets were evaluated. 展开更多
关键词 double PROJECTION point
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Exceptional points and quantum dynamics in a non-Hermitian two-qubit system
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作者 张益玺 张振涛 +2 位作者 杨震山 魏晓志 梁宝龙 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第6期212-218,共7页
We study the exceptional-point(EP) structure and the associated quantum dynamics in a system consisting of a non-Hermitian qubit and a Hermitian qubit. We find that the system possesses two sets of EPs, which divide t... We study the exceptional-point(EP) structure and the associated quantum dynamics in a system consisting of a non-Hermitian qubit and a Hermitian qubit. We find that the system possesses two sets of EPs, which divide the systemparameter space into PT-symmetry unbroken, partially broken and fully broken regimes, each with distinct quantumdynamics characteristics. Particularly, in the partially broken regime, while the PT-symmetry is generally broken in the whole four-dimensional Hilbert space, it is preserved in a two-dimensional subspace such that the quantum dynamics in the subspace are similar to those in the PT-symmetry unbroken regime. In addition, we reveal that the competition between the inter-qubit coupling and the intra-qubit driving gives rise to a complex pattern in the EP variation with system parameters. 展开更多
关键词 non-Hermitian system exceptional point PT-SYMMETRY
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