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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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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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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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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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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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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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On a Heuristic Point of View about the Generalization of Curie Law to Cosmic Higgs Fields with the Casimir Effect
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作者 Hung-Te Henry Su Po-Han Lee 《Journal of Applied Mathematics and Physics》 2024年第9期3135-3147,共13页
Condensed state physics demonstrates that the Curie temperature is the point at which spontaneous magnetization drops to zero, marking the critical transition where ferromagnetic or ferrimagnetic materials transform i... Condensed state physics demonstrates that the Curie temperature is the point at which spontaneous magnetization drops to zero, marking the critical transition where ferromagnetic or ferrimagnetic materials transform into paramagnetic substances. Below the Curie temperature, a material remains ferromagnetic;above it, the material becomes paramagnetic, with its magnetic field easily influenced by external magnetic fileds. For example, the Curie temperature of iron (Fe) is 1043 K, while that of neodymium magnets ranges from 583 to 673 K. From both physics and mathematics perspectives, examining the temperature properties of materials is essential, as it provides valuable insights into their electromagnetic and thermodynamic behaviors. This paper makes a bold assumption and, for the first time, carefully verifies the existence of a Casimir temperature at 0.00206 K under conditions of one-atomic spacing. 展开更多
关键词 Curie Temperature Curie point Casimir Temperature Critical point Fields Materials One-Atomic Spacing
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Qualitative Properties of Equilibrium Point in a Discrete Predator-Prey Model
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作者 Weijie Lin Minhong Yang +2 位作者 Chenhao Sun Kaiwen Guan Xiaoliang Zhou 《Journal of Applied Mathematics and Physics》 2024年第8期2920-2927,共8页
In this paper, the dynamic properties of a discrete predator-prey model are discussed. The properties of non-hyperbolic fixed points and hyperbolic fixed points of the model are analyzed. First, by using the classic S... In this paper, the dynamic properties of a discrete predator-prey model are discussed. The properties of non-hyperbolic fixed points and hyperbolic fixed points of the model are analyzed. First, by using the classic Shengjin formula, we find the existence conditions for fixed points of the model. Then, by using the qualitative theory of ordinary differential equations and matrix theory we indicate which points are hyperbolic and which are non-hyperbolic and the associated conditions. 展开更多
关键词 Discrete Predator-Prey Model Non-Hyperbolic Fixed point NODE Saddle point
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Efficacy comparison of multipoint and single point scanning panretinal laser photocoagulation in non-proliferative diabetic retinopathy treatment
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作者 Yang-Zhou Zhang Hua Gong +2 位作者 Juan Yang Ji-Pu Bu Hui-Ling Yang 《World Journal of Diabetes》 SCIE 2024年第8期1734-1741,共8页
BACKGROUND Non-proliferative diabetic retinopathy(NPDR)poses a significant challenge in diabetes management due to its microvascular changes in the retina.Laser photocoagulation,a conventional therapy,aims to mitigate... BACKGROUND Non-proliferative diabetic retinopathy(NPDR)poses a significant challenge in diabetes management due to its microvascular changes in the retina.Laser photocoagulation,a conventional therapy,aims to mitigate the risk of progressing to proliferative diabetic retinopathy(PDR).AIM To compare the efficacy and safety of multi-spot vs single-spot scanning panretinal laser photocoagulation in NPDR patients.METHODS Forty-nine NPDR patients(86 eyes)treated between September 2020 and July 2022 were included.They were randomly allocated into single-spot(n=23,40 eyes)and multi-spot(n=26,46 eyes)groups.Treatment outcomes,including bestcorrected visual acuity(BCVA),central macular thickness(CMT),and mean threshold sensitivity,were assessed at predetermined intervals over 12 months.Adverse reactions were also recorded.RESULTS Energy levels did not significantly differ between groups(P>0.05),but the multi-spot group exhibited lower energy density(P<0.05).BCVA and CMT improvements were noted in the multi-spot group at one-month posttreatment(P<0.05).Adverse reaction incidence was similar between groups(P>0.05).CONCLUSION While energy intensity and safety were comparable between modalities,multi-spot scanning demonstrated lower energy density and showed superior short-term improvements in BCVA and CMT for NPDR patients,with reduced laser-induced damage. 展开更多
关键词 Panretinal laser photocoagulation Non-proliferative diabetic retinopathy Efficacy comparison Multipoint Single point Treatment assessment
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Building Facade Point Clouds Segmentation Based on Optimal Dual-Scale Feature Descriptors
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作者 Zijian Zhang Jicang Wu 《Journal of Computer and Communications》 2024年第6期226-245,共20页
To address the current issues of inaccurate segmentation and the limited applicability of segmentation methods for building facades in point clouds, we propose a facade segmentation algorithm based on optimal dual-sca... To address the current issues of inaccurate segmentation and the limited applicability of segmentation methods for building facades in point clouds, we propose a facade segmentation algorithm based on optimal dual-scale feature descriptors. First, we select the optimal dual-scale descriptors from a range of feature descriptors. Next, we segment the facade according to the threshold value of the chosen optimal dual-scale descriptors. Finally, we use RANSAC (Random Sample Consensus) to fit the segmented surface and optimize the fitting result. Experimental results show that, compared to commonly used facade segmentation algorithms, the proposed method yields more accurate segmentation results, providing a robust data foundation for subsequent 3D model reconstruction of buildings. 展开更多
关键词 3D Laser Scanning point Clouds Building Facade Segmentation point Cloud Processing Feature Descriptors
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Existence of Monotone Positive Solution for a Fourth-Order Three-Point BVP with Sign-Changing Green’s Function
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作者 Junrui Yue Yun Zhang Qingyue Bai 《Open Journal of Applied Sciences》 2024年第1期63-69,共7页
This paper is concerned with the following fourth-order three-point boundary value problem , where , we discuss the existence of positive solutions to the above problem by applying to the fixed point theory in cones a... This paper is concerned with the following fourth-order three-point boundary value problem , where , we discuss the existence of positive solutions to the above problem by applying to the fixed point theory in cones and iterative technique. 展开更多
关键词 Fourth-Order Three-point Boundary Value Problem Sign-Changing Green’s Function Fixed point Index Iterative Technique Monotone Positive Solution EXISTENCE
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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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基于DenseNet与PointNet融合算法的三维点云分割
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作者 吴烈权 周志峰 +1 位作者 时云 任朴林 《应用光学》 CAS 北大核心 2024年第5期982-991,共10页
点云分割对于智能驾驶、物体检测和识别、逆向工程等任务非常重要。PointNet是一种能够直接处理点云数据的方法,近年来在点云分割任务中得到广泛应用,但其分割精度较低,而PointNet++的计算成本又较高。针对以上问题,提出一种融合DenseNe... 点云分割对于智能驾驶、物体检测和识别、逆向工程等任务非常重要。PointNet是一种能够直接处理点云数据的方法,近年来在点云分割任务中得到广泛应用,但其分割精度较低,而PointNet++的计算成本又较高。针对以上问题,提出一种融合DenseNet和PointNet的算法,用于点云分割,并引入三分支混合注意力机制,以提高PointNet在提取局部特征方面的能力。基于密集连接卷积网络(DenseNet)思想,提出用DenseNet-STN和DenseNet-MLP结构来替代PointNet中的空间变换网络(STN)和多层感知机(MLP);同时,使用Add连接代替密集块(DenseBlock)中的Concat连接,以提高对点特征间相关性的准确性,同时不显著增加模型复杂度。DenseNet-PointNet能够提高复杂分类问题的泛化能力,实现对复杂函数更好的逼近,从而提高点云分割的准确率。有效性和消融实验结果表明,本文算法具有良好的性能。点云分割实验结果表明,DenseNet-PointNet在大多数类别中的交并比(IoU)都高于PointNet的IoU,并在部分类别中也高于PointNet++,参数量是PointNet++的47.6%,浮点运算量(FLOPs)是PointNet++的49.1%。实验结果验证了DenseNet-PointNet的可行性和有效性。 展开更多
关键词 点云分割 密集连接卷积网络 pointNet DenseNet-pointNet
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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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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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