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Multi-frequency non-reciprocal optical directional amplifier realized with non-Hermitian resonator arrays
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作者 Jin-Xiang Xue Chuan-Xun Du +2 位作者 Cheng-Chao Liu Liu Yang Yong-Long Wang 《Chinese Physics B》 2026年第2期423-432,共10页
For a multi-frequency non-reciprocal optical device,we first realize multi-frequency optical non-reciprocal transmission using a non-Hermitian multi-mode resonator array.Practically,multi-frequency operation can add c... For a multi-frequency non-reciprocal optical device,we first realize multi-frequency optical non-reciprocal transmission using a non-Hermitian multi-mode resonator array.Practically,multi-frequency operation can add channels to the non-reciprocal optical device and the non-reciprocity can route optical signals and prevent the reverse flow of noise.Using the Scully–Lamb model and gain saturation effect,we accomplish dual-frequency non-reciprocal transmission by introducing nonlinearity into a linear array of four-mode resonators.The accomplishment is directly demonstrated by the non-reciprocal transmission phenomena present in the non-divergent peaks.For example,a directional cyclic amplifier is constructed with non-reciprocal units.Regarding potential applications,non-reciprocal optical systems can be employed in dual-frequency control,parallel information processing,photonic integrated circuits,optical devices and so on. 展开更多
关键词 non-Hermitian systems PT-SYMMETRY multi-frequency of non-reciprocity optical directional amplifier
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Ultrastructure and key identification points of fossilized Os Draconis in traditional Chinese medicine
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作者 Dong-Han Bai Zi Xing +5 位作者 Zi-Hao Zhang Zhi-Jie Zhang Da-Jun Lu Nan-Xi Huang Qiao-Chu Wang Lu Luo 《Traditional Medicine Research》 2026年第1期39-46,共8页
Background:The medicinal material known as Os Draconis(Longgu)originates from fossilized remains of ancient mammals and is widely used in treating emotional and mental conditions.However,fossil resources are nonrenewa... Background:The medicinal material known as Os Draconis(Longgu)originates from fossilized remains of ancient mammals and is widely used in treating emotional and mental conditions.However,fossil resources are nonrenewable,and clinical demand is increasingly difficult to meet,leading to a proliferation of counterfeit products.During prolonged geological burial,static pressure from the surrounding strata severely compromises the microstructural integrity of osteons in Os Draconis,but Os Draconis still largely retains the structural features of mammalian bone.Methods:Using verified authentic Os Draconis samples over 10,000 years old as a baseline,this study summarizes the ultrastructural characteristics of genuine Os Draconis.Employing electron probe microanalysis and optical polarized light microscopy,we examined 28 batches of authentic Os Draconis and 31 batches of counterfeits to identify their ultrastructural differences.Key points for ultrastructural identification of Os Draconis were compiled,and a new identification approach was proposed based on these differences.Results:Authentic Os Draconis exhibited distinct ultrastructural markers:irregularly shaped osteons with traversing fissures,deformed/displaced Haversian canals,and secondary mineral infill(predominantly calcium carbonate).Counterfeits showed regular osteon arrangements,absent traversal fissures,and homogeneous hydroxyapatite composition.Lab-simulated samples lacked structural degradation features.EPMA confirmed calcium carbonate infill in fossilized Haversian canals,while elemental profiles differentiated lacunae types(void vs.mineral-packed).Conclusion:The study established ultrastructural criteria for authentic Os Draconis identification:osteon deformation,geological fissures penetrating bone units,and heterogenous mineral deposition.These features,unattainable in counterfeits or modern processed bones,provide a cost-effective,accurate identification method.This approach bridges gaps in TCM material standardization and supports quality control for clinical applications. 展开更多
关键词 Os Draconis ULTRASTRUCTURE identification points electron probe polarized light microscope
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An intelligent segmentation method for leakage points in central serous chorioretinopathy based on fluorescein angiography images
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作者 Jian-Guo Xu Yong-Chi Liu +4 位作者 Fen Zhou Jian-Xin Shen Zhi-Peng Yan Xin-Ya Hu Wei-Hua Yang 《International Journal of Ophthalmology(English edition)》 2026年第3期421-433,共13页
AIM:To construct an intelligent segmentation scheme for precise localization of central serous chorioretinopathy(CSC)leakage points,thereby enabling ophthalmologists to deliver accurate laser treatment without navigat... AIM:To construct an intelligent segmentation scheme for precise localization of central serous chorioretinopathy(CSC)leakage points,thereby enabling ophthalmologists to deliver accurate laser treatment without navigational laser equipment.METHODS:A dataset with dual labels(point-level and pixel-level)was first established based on fundus fluorescein angiography(FFA)images of CSC and subsequently divided into training(102 images),validation(40 images),and test(40 images)datasets.An intelligent segmentation method was then developed,based on the You Only Look Once version 8 Pose Estimation(YOLOv8-Pose)model and segment anything model(SAM),to segment CSC leakage points.Next,the YOLOv8-Pose model was trained for 200 epochs,and the best-performing model was selected to form the optimal combination with SAM.Additionally,the classic five types of U-Net series models[i.e.,U-Net,recurrent residual U-Net(R2U-Net),attention U-Net(AttU-Net),recurrent residual attention U-Net(R2AttUNet),and nested U-Net(UNet^(++))]were initialized with three random seeds and trained for 200 epochs,resulting in a total of 15 baseline models for comparison.Finally,based on the metrics including Dice similarity coefficient(DICE),intersection over union(IoU),precision,recall,precisionrecall(PR)curve,and receiver operating characteristic(ROC)curve,the proposed method was compared with baseline models through quantitative and qualitative experiments for leakage point segmentation,thereby demonstrating its effectiveness.RESULTS:With the increase of training epochs,the mAP50-95,Recall,and precision of the YOLOv8-Pose model showed a significant increase and tended to stabilize,and it achieved a preliminary localization success rate of 90%(i.e.,36 images)for CSC leakage points in 40 test images.Using manually expert-annotated pixel-level labels as the ground truth,the proposed method achieved outcomes with a DICE of 57.13%,an IoU of 45.31%,a precision of 45.91%,a recall of 93.57%,an area under the PR curve(AUC-PR)of 0.78 and an area under the ROC curve(AUC-ROC)of 0.97,which enables more accurate segmentation of CSC leakage points.CONCLUSION:By combining the precise localization capability of the YOLOv8-Pose model with the robust and flexible segmentation ability of SAM,the proposed method not only demonstrates the effectiveness of the YOLOv8-Pose model in detecting keypoint coordinates of CSC leakage points from the perspective of application innovation but also establishes a novel approach for accurate segmentation of CSC leakage points through the“detect-then-segment”strategy,thereby providing a potential auxiliary means for the automatic and precise realtime localization of leakage points during traditional laser photocoagulation for CSC. 展开更多
关键词 You Only Look Once version 8 Pose Estimation segment anything model central serous chorioretinopathy leakage point segmentation
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Nomenclature and location of acupuncture points for laboratory animals Part 3:Mouse 被引量:3
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作者 《World Journal of Acupuncture-Moxibustion》 2025年第2期160-162,共3页
This paper introduces part of the content in the association standard,T/CAAM0002–2020 Nomenclature and Location of Acupuncture Points for Laboratory Animals Part 3:Mouse.This standard was released by the China Associ... This paper introduces part of the content in the association standard,T/CAAM0002–2020 Nomenclature and Location of Acupuncture Points for Laboratory Animals Part 3:Mouse.This standard was released by the China Association of Acupuncture and Moxibustion on May 15,2020,implemented on October 31,2020,and published by Standards Press of China.The standard was drafted by the Institute of Acupuncture and Moxibustion,China Academy of Chinese Medical Sciences,and the Nanjing University of Chinese Medicine.Principal draftsmen:Xiang-hong JING and Xing-bang HUA.Participating draftsmen:Wan-zhu BAI,Bin XU,Dong-sheng XU,Yi GUO,Tie-ming MA,Xin-jun WANG,and Sheng-feng LU. 展开更多
关键词 acupuncture points STANDARD MOUSE NOMENCLATURE location acupuncture points association standardt caam LOCATION acupuncture moxibustion
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Multi-frequency formation mechanism and modulation strategy of self-priming enhanced submerged pulsed waterjet 被引量:1
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作者 Haojie Jia Yanwei Liu +6 位作者 Weiqin Zuo Hongkai Han Ping Chang Mohammad Waqar Ali Asad Guozhong Hu Jian Miao Hani SMitri 《International Journal of Mining Science and Technology》 2025年第2期175-189,共15页
Under submerged conditions, compared with traditional self-excited oscillating pulsed waterjets(SOPWs), annular fluid-enhanced self-excited oscillating pulsed waterjets(AFESOPWs) exhibit a higher surge pressure throug... Under submerged conditions, compared with traditional self-excited oscillating pulsed waterjets(SOPWs), annular fluid-enhanced self-excited oscillating pulsed waterjets(AFESOPWs) exhibit a higher surge pressure through self-priming. However, their pressure frequency and cavitation characteristics remain unclear, resulting in an inability to fully utilize resonance and cavitation erosion to break coal and rock. In this study, high-frequency pressure testing, high-speed photography, and large eddy simulation(LES) are used to investigate the distribution of the pressure frequency band, evolution law of the cavitation cloud, and its regulation mechanism of a continuous waterjet, SOPW, and AFESOPW. The results indicated that the excitation of the plunger pump, shearing layer vortex, and bubble collapse corresponded to the three high-amplitude frequency bands of the waterjet pressure. AFESOPWs have an additional self-priming frequency that can produce a larger amplitude under a synergistic effect with the second high-amplitude frequency band. A better cavitation effect was produced after self-priming the annulus fluid, and the shedding frequency of the cavitation clouds of the three types of waterjets was linearly related to the cavitation number. The peak pressure of the waterjet and cavitation erosion effect can be improved by modulating the waterjet pressure oscillation frequency and cavitation shedding frequency. 展开更多
关键词 multi-frequency Modulation SELF-PRIMING Submerged waterjet CAVITATION
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Nomenclature and location of acupuncture points for laboratory animals Part 2 被引量:2
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作者 《World Journal of Acupuncture-Moxibustion》 2025年第2期163-165,共3页
This paper introduces part of the content in the association standard,T/CAAM0002–2020 Nomenclature and Location of Acupuncture Points for Laboratory Animals Part 2:Rat.This standard was released by the China Associat... This paper introduces part of the content in the association standard,T/CAAM0002–2020 Nomenclature and Location of Acupuncture Points for Laboratory Animals Part 2:Rat.This standard was released by the China Association of Acupuncture and Moxibustion on May 15,2020,implemented on October 31,2020,and published by Standards Press of China.The standard was drafted by the Institute of Acupuncture and Moxibustion,China Academy of Chinese Medical Sciences,and the Nanjing University of Chinese Medicine.Principal draftsmen:Xiang-hong JING and Xing-bang HUA.Participating draftsmen:Wan-Zhu BAI,Bin XU,Dong-sheng XU,Yi GUO,Tie-ming MA,Xin-jun WANG,and Sheng-feng LU. 展开更多
关键词 acupuncture points STANDARD NOMENCLATURE rat association standardt caam LOCATION acupuncture moxibustion
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Rapid springtime leaf osmotic adjustment,but low late-seasonal and interannual variation in leaf turgor loss points in three temperate tree species 被引量:1
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作者 Norbert Kunert 《Journal of Forestry Research》 2025年第4期31-40,共10页
Leaf turgor loss point has been recognized as an important plant physiological trait explaining a species’drought tolerance( π_(tlp)).Less is known about the variation of π_(tlp) in time and how seasonal or interan... Leaf turgor loss point has been recognized as an important plant physiological trait explaining a species’drought tolerance( π_(tlp)).Less is known about the variation of π_(tlp) in time and how seasonal or interannual differences in water availability are affecting π_(tlp) as a static trait.I monitored the seasonal variation of π_(tlp) during a drought year starting in early spring with juvenile leaves and assessed the interannual variation in π_(tlp) of fully matured leaves among years with diverting water availability for three temperate broad-leaved tree species.The largest seasonal changes in π_(tlp) occurred during leaf unfolding until leaves were fully developed and matured.After leaves matured,no significant changes occurred for the rest of the vegetation period.Interannual variation that could be related to water availability was only present in one of the three tree species.The results suggest that the investigated species have a rapid period of osmotic adjustment early in the growing season followed by a period of relative stability,when π_(tlp) can be considered as a static trait. 展开更多
关键词 Drought Leaf drought tolerance traits Tree mortality Turgor loss point
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基于WSS-Pointnet的变电站点云弱监督语义分割方法
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作者 裴少通 孙海超 +2 位作者 胡晨龙 王玮琦 兰博 《电工技术学报》 北大核心 2026年第1期234-245,共12页
现有的变电站点云语义分割算法均采用完全监督学习,需要大量人工标注点云数据,导致分割任务耗时长且成本高昂。为解决这一问题,该文提出一种基于PointNet改进的弱监督语义分割PointNet(WSS-PointNet)算法。首先,通过构建多层降采样结构... 现有的变电站点云语义分割算法均采用完全监督学习,需要大量人工标注点云数据,导致分割任务耗时长且成本高昂。为解决这一问题,该文提出一种基于PointNet改进的弱监督语义分割PointNet(WSS-PointNet)算法。首先,通过构建多层降采样结构,结合采样层与分组层对输入点云数据进行多尺度特征提取,从而捕捉点云在不同尺度上的几何和拓扑信息。在此基础上,引入PointNet结构以进一步提取区域特征,优化局部特征整合与全局特征表示;针对粗粒度语义特征的优化,提出膨胀式语义信息嵌入与浸染式语义信息嵌入两种模块,分别采用“由内而外”和“由外而内”的信息传递策略对点云语义信息进行细致处理,两种嵌入机制均基于图卷积神经网络,通过捕捉局部连接模式与信息共享实现语义特征的高效传播。其次,构建变电站点云数据集,并对WSS-PointNet算法进行消融实验,同时与主流的完全监督学习算法和弱监督学习算法进行对比。经实验验证,WSS-PointNet相比于改进前将变电站点云分割的总体精度(OA)提高了10.3个百分点,平均交并比(mIoU)提高了10.1个百分点,平均准确率(mAcc)提高了10.5个百分点,同时在标注所需时间方面缩短了90%,接近完全监督算法中最好的分割效果。该模型可显著降低处理变电站点云数据的时间与成本,同时保持点云分割的高精度。 展开更多
关键词 点云语义分割 弱监督方法 膨胀式语义信息嵌入 浸染式语义信息嵌入 变电站
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Nonlinear Resonance Response of Suspended Cables Under Multi-Frequency Excitations and Time-Delayed Feedback
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作者 Jian Peng Hui Xia +2 位作者 Lianhua Wang Xiaoyu Zhang Xianzhong Xie 《Acta Mechanica Solida Sinica》 2025年第4期689-700,共12页
This study investigates the nonlinear resonance responses of suspended cables subjected to multi-frequency excitations and time-delayed feedback.Two specific combinations and simultaneous resonances are selected for d... This study investigates the nonlinear resonance responses of suspended cables subjected to multi-frequency excitations and time-delayed feedback.Two specific combinations and simultaneous resonances are selected for detailed examination.Initially,utilizing Hamilton’s variational principle,a nonlinear vibration control model of suspended cables under multi-frequency excitations and longitudinal time-delayed velocity feedback is developed,and the Galerkin method is employed to obtain the discrete model.Subsequently,focusing solely on single-mode discretization,analytical solutions for the two simultaneous resonances are derived using the method of multiple scales.The frequency response equations are derived,and the stability analysis is presented for two simultaneous resonance cases.The results demonstrate that suspended cables exhibit complex nonlinearity under multi-frequency excitations.Multiple solutions under multi-frequency excitation can be distinguished through the frequency–response and the detuning-phase curves.By adjusting the control gain and time delay,the resonance range,response amplitude,and phase of suspended cables can be modified. 展开更多
关键词 Suspended cables multi-frequency excitation Time-delayed feedback Nonlinear resonance response
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Therapeutic Effects of 35 kDa Hyaluronan Injection at Trigger Points in the Treatment of Myofascial Pain Syndrome
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作者 Enkhbat Purevsuren Dylan Treger +5 位作者 Zhaohui Ma Xiaoxiao Jia Taivanbat Ganbaatar Munkh-Amgalan Gantumur Mizhou Hui Davaajargal Nkhtuvshin 《International Journal of Clinical Medicine》 2025年第1期1-15,共15页
Objectives: This study aimed to evaluate the prolonged therapeutic effects of a 35 kDa molecular weight hyaluronan fragment (HA35) in alleviating pain associated with myofascial pain syndrome (MPS). Hyaluronan interac... Objectives: This study aimed to evaluate the prolonged therapeutic effects of a 35 kDa molecular weight hyaluronan fragment (HA35) in alleviating pain associated with myofascial pain syndrome (MPS). Hyaluronan interacts with various receptors in the human body, including CD44, LYVE-1, RHAMM, and TLR2, and is well-known for its analgesic effects when used in intra-articular or ultrasound-guided nerve trunk injections. Studies have shown that hyaluronidase cleaves high molecular weight HA to generate HA35, a low molecular weight fragment with enhanced tissue permeability, capable of binding to HA receptors on cell surfaces to produce broad-spectrum analgesic effects. Methods: Ten patients diagnosed with MPS were treated and assessed in this study. HA35 was administered through injection at a dosage of 100 mg daily for 15 days. Patients evaluated their MPS, overall pain levels, and treatment satisfaction using the Numerical Pain Rating Scale (NPRS), the Global Pain Scale (GPS), and the Treatment Satisfaction Questionnaire for Medication (TSQM 1.4). Follow-up evaluations were performed three months post-treatment to assess the duration of therapeutic effects. Results: Significant improvements were observed in NPRS, GPS, and TSQM scores both during and after the treatment period (P Conclusions: HA35 provides effective and sustained relief from pain associated with MPS, demonstrating a prolonged therapeutic benefit. 展开更多
关键词 35 kDa Hyaluronan Fragment HA35 PAIN Myofascial Pain Syndrome Myofascial Trigger points
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Multi-frequency Jitter Detection and Modeling for Remote Sensing Satellite Platforms Using Non-collinear TDI CCD
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作者 ZHU Ying LI Xiaoqian +3 位作者 DONG Yanling GUI Yuhao LIAO Xiangjun ZHANG Xin 《Transactions of Nanjing University of Aeronautics and Astronautics》 2025年第5期601-614,共14页
The advancement of imaging resolution has made the impact of multi-frequency composite jitter in satellite platforms on non-collinear time delay and integration(TDI)charge-coupled device(CCD)imaging systems increasing... The advancement of imaging resolution has made the impact of multi-frequency composite jitter in satellite platforms on non-collinear time delay and integration(TDI)charge-coupled device(CCD)imaging systems increasingly critical.Moreover,the accuracy of jitter detection is constrained by the limited inter-chip overlap region inherent to non-collinear TDI CCDs.To address these challenges,a multi-frequency jitter detection method is proposed,achieving sub-pixel level error extraction.Furthermore,a multi-frequency jitter fitting approach utilizing a scale-adjustable sliding window is introduced.For composite multi-frequency jitter,spectral analysis decomposes the relative jitter error curve,while the scale-adjustable sliding window enables frequency-division fitting and modeling.Validation experiments using Gaofen-8(GF-8)remote sensing satellite imagery detected jitter at 0.65,20,and 100 Hz in the cross-track direction and at 0.5,100,and 120 Hz in the along-track direction,demonstrating the method’s precision in detecting platform jitter at sub-pixel accuracy(<0.2 pixels)and its efficacy in fitting and modeling for non-collinear TDI CCD imaging systems subject to multi-frequency jitter. 展开更多
关键词 remote sensing image matching platform jitter non-collinear TDI CCD multi-frequency jitter fitting
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Observation of exceptional points and realization of high sensitivity sensing in electric circuits
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作者 Jiaxi Cai Xinyi Wang +2 位作者 Xiaomin Zhang Taoran Yue Jijun Wang 《Chinese Physics B》 2025年第12期502-510,共9页
We explore the parity-time(PT)-symmetry breaking transition in a dimer circuit composed of two RLC resonators that are weakly coupled via an inductor.The energy behavior of this dimer circuit is reflected in the split... We explore the parity-time(PT)-symmetry breaking transition in a dimer circuit composed of two RLC resonators that are weakly coupled via an inductor.The energy behavior of this dimer circuit is reflected in the splitting or degeneracy of the systems eigenfrequencies as the gain–loss strength varies.Its dynamical properties can be described by a non-Hermitian Hamiltonian.The eigenfrequency spectrum of the system is divided by two critical points into three distinct regions:the symmetric region,the oscillatory growth region,and the fully exponential growth region.Building upon previous work on implementing the exceptional point(EP)in circuit systems,our study focuses on further exploring the variation patterns of circuit eigenfrequencies near the EP under weak coupling conditions.In addition,we construct a corresponding Dirac point(DP)circuit system for comparison.By leveraging the unique physical properties near both the EP and the DP,we further propose potential practical applications.Using perturbation theory and system simulations,we demonstrate that the square-root eigenfrequency splitting near the EP significantly enhances the sensitivity to small external perturbations,compared to the linear splitting behavior near the DP.This study presents promising prospects for next-generation sensing technologies. 展开更多
关键词 parity-time symmetry exceptional point Dirac point high sensitivity sensor
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PT-MFR:一种基于Point Transformer的CAD模型加工特征识别方法
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作者 何皓辰 方正 +2 位作者 卢政达 肖俊 王颖 《中国科学院大学学报(中英文)》 北大核心 2026年第1期115-124,共10页
加工特征识别在计算机辅助设计(CAD)和制造(CAM)中至关重要,是连接CAD和CAM系统的重要环节。研究者们提出了基于规则和基于学习的2类加工特征识别方法,其中基于学习的方法表现更出色且备受关注。然而,现有识别方法面临着几何信息利用不... 加工特征识别在计算机辅助设计(CAD)和制造(CAM)中至关重要,是连接CAD和CAM系统的重要环节。研究者们提出了基于规则和基于学习的2类加工特征识别方法,其中基于学习的方法表现更出色且备受关注。然而,现有识别方法面临着几何信息利用不足、加工特征定位不精准、实例分割过程复杂等挑战。针对这些问题,提出PT-MFR,一种基于Point Transformer的CAD模型加工特征识别方法,它执行语义分割和实例分割2个任务,分别预测模型每个面的加工特征语义类别并计算面相似度以分割加工特征实例,综合2个任务得到加工特征识别结果。实验结果表明,提出的方法性能优于现有的其他方法。 展开更多
关键词 加工特征识别 点云 神经网络 point Transformer
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A Method for Automatic Feature Points Extraction of Pelvic Surface Based on PointMLP_RegNet
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作者 Wei Kou Rui Zhou +5 位作者 Hongmiao Zhang Jianwen Cheng Chi Zhu Shaolong Kuang Lihai Zhang Lining Sun 《CAAI Transactions on Intelligence Technology》 2025年第3期716-727,共12页
The success of robot-assisted pelvic fracture reduction surgery heavily relies on the accuracy of 3D/3D feature-based registration.This process involves extracting anatomical feature points from pre-operative 3D image... The success of robot-assisted pelvic fracture reduction surgery heavily relies on the accuracy of 3D/3D feature-based registration.This process involves extracting anatomical feature points from pre-operative 3D images which can be challenging because of the complex and variable structure of the pelvis.PointMLP_RegNet,a modified PointMLP,was introduced to address this issue.It retains the feature extraction module of PointMLP but replaces the classification layer with a regression layer to predict the coordinates of feature points instead of conducting regular classification.A flowchart for an automatic feature points extraction method was presented,and a series of experiments was conducted on a clinical pelvic dataset to confirm the accuracy and effectiveness of the method.PointMLP_RegNet extracted feature points more accurately,with 8 out of 10 points showing less than 4 mm errors and the remaining two less than 5 mm.Compared to PointNettt and PointNet,it exhibited higher accuracy,robustness and space efficiency.The proposed method will improve the accuracy of anatomical feature points extraction,enhance intra-operative registration precision and facilitate the widespread clinical application of robot-assisted pelvic fracture reduction. 展开更多
关键词 automatic feature points extraction feature points intra-operative registration pointMLP_RegNet robot-assisted pelvic fracture reduction surgery
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Comparison between the effects of Hamiltonian and Liouvillian exceptional points on the Leggett–Garg inequality and no-signaling-in-time conditions
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作者 Kun-Jie Zhou Jian Zou +1 位作者 Bao-Ming Xu Bin Shao 《Communications in Theoretical Physics》 2025年第8期35-48,共14页
In this paper, we investigate the effect of exceptional points(EPs) on the violation of Leggett–Garg inequality(LGI) and no-signaling-in-time(NSIT) conditions and compare the different effects between the Hamiltonian... In this paper, we investigate the effect of exceptional points(EPs) on the violation of Leggett–Garg inequality(LGI) and no-signaling-in-time(NSIT) conditions and compare the different effects between the Hamiltonian EP(HEP) and Liouvillian EP(LEP) on those violations. We consider an open system consisting of two coupled qubits and each qubit is contacted with a thermal bath at a different temperature. In the case of omitting quantum jumps, we find that the system exhibits a second-order HEP, which separates the parameter space into an overdamped regime and an underdamped regime. In this situation, the LGI and NSIT conditions can be violated in both regimes and not violated at the HEP. In the case of without omitting quantum jumps, we find that the system exhibits a third-order LEP, which also separates the parameter space into an overdamped regime and an underdamped regime. In this situation, the LGI can only be violated in the underdamped regime with large coupling strength between the qubits.Conversely, the NSIT conditions can be violated in both regimes, as well as at the LEP, except in the overdamped regime with small coupling strength between the qubits. Comparing the violations of the LGI and NSIT conditions with HEP and LEP, we find that the quantum jumps would reduce the generation of coherence, enhance the decoherence, and lead to narrower parameter regimes that the LGI and NSIT conditions can be violated. Furthermore, in both cases,the NSIT conditions can be violated in a wider parameter regime than the LGI. 展开更多
关键词 exceptional points Leggett–Garg inequality no-signaling-in-time conditions
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Thermal stress concentration points and stress mutations in nano-multilayer film structures
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作者 Ying Zheng Zhi You Wang +6 位作者 Qianju Song Zao Yi Shubo Cheng Can Ma Chaojun Tang Qingdong Zeng Sohail Ahmad 《Communications in Theoretical Physics》 2025年第1期179-189,共11页
In the multilayer film-substrate system,thermal stress concentration and stress mutations cause film buckling,delamination and cracking,leading to device failure.In this paper,we investigated a multilayer film system ... In the multilayer film-substrate system,thermal stress concentration and stress mutations cause film buckling,delamination and cracking,leading to device failure.In this paper,we investigated a multilayer film system composed of a substrate and three film layers.The thermal stress distribution inside the structure was calculated by the finite element method,revealing significant thermal stress differences between the layers.This is mainly due to the mismatch of the coefficient of thermal expansion between materials.Different materials respond differently to changes in external temperature,leading to compression between layers.There are obvious thermal stress concentration points at the corners of the base layer and the transition layer,which is due to the sudden change of the shape at the geometric section of the structure,resulting in a sudden increase in local stress.To address this issue,we chamfered the substrate and added an intermediate layer between the substrate and the transition layer to assess whether these modifications could reduce or eliminate the thermal stress concentration points and extend the service life of the multilayer structure.The results indicate that chamfering and adding the intermediate layer effectively reduce stress discontinuities and mitigate thermal stress concentration points,thereby improving interlayer bonding strength. 展开更多
关键词 multilayer structure thermal stress concentration point stress mutation CHAMFER intermediate layer
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基于改进PointNet++的服装点云分割与边界优化
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作者 徐诗琦 马玲 +2 位作者 林熹妍 潘怡婷 邹奉元 《现代纺织技术》 北大核心 2026年第2期90-98,共9页
人体与服装及服装不同部位之间的边界区域常包含复杂几何特征与变化,使得三维点云场景分割方法在进行服装提取时边界分割效果较差,进而影响整体精度。为了提高服装点云分割精度,提出一种融合边界识别的改进PointNet++模型,以提高边界区... 人体与服装及服装不同部位之间的边界区域常包含复杂几何特征与变化,使得三维点云场景分割方法在进行服装提取时边界分割效果较差,进而影响整体精度。为了提高服装点云分割精度,提出一种融合边界识别的改进PointNet++模型,以提高边界区域的分割性能。首先,对输入三维服装点云数据进行初步分割。接着,在初始部件分割结果的基础上,设计基于K邻近算法的边界识别模块并嵌入PointNet++模型,以对初步分割边界进行针对性训练。最后,利用优化后的局部区域提高三维服装的整体分割精度。结果表明:改进PointNet++模型方法在边界区域的总体精度与平均交并比分别为87.37%与86.68%,比基线方法分别提升了32.74%、34.25%。整体区域的总体精度与平均交并比分别为93.53%与92.84%,比基线方法分别提升了1.19%、0.89%。研究方法可显著提升三维服装边界分割精度,为三维服装提取提供技术参考。 展开更多
关键词 三维服装提取 三维点云 pointNet++ 点云分割 边界优化
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Research on the Treatment of Dysphagia Caused by True Bulbar Paralysis after Stroke with Electroacupuncture at Swallowing Points
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作者 Shiting Zhu 《Journal of Clinical and Nursing Research》 2025年第3期179-184,共6页
Dysphagia caused by true bulbar paralysis after stroke is a common and serious complication that severely affects patients’eating ability and quality of life,and significantly increases the risk of complications such... Dysphagia caused by true bulbar paralysis after stroke is a common and serious complication that severely affects patients’eating ability and quality of life,and significantly increases the risk of complications such as pneumonia and malnutrition.Electroacupuncture at swallowing points stimulates Swallowing 1 and Swallowing 2 acupoints,acting on key areas such as the glossopharyngeal nerve and vagus nerve,stimulating the reconstruction of nerve reflex arcs and the recovery of swallowing function.Therefore,this article analyzes the mechanism and clinical efficacy of electroacupuncture at swallowing points for the treatment of dysphagia caused by true bulbar paralysis after stroke,aiming to provide theoretical support and practical basis for clinical application. 展开更多
关键词 Electroacupuncture at swallowing points STROKE Dysphagia caused by true bulbar paralysis Clinical progress
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Establishment of normal operating zone models by boundary points for CSTR-DC-recycle chemical processes
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作者 Poku Gyasi Jiandong Wang +1 位作者 Mengyao Wei Hao Jing 《Chinese Journal of Chemical Engineering》 2025年第9期140-157,共18页
Integrated continuous stirred-tank reactors and distillation columns with recycle(CSTR-DC-recycle)are essential components in chemical processes.This paper proposes a method to establish a normal operating zone(NOZ)mo... Integrated continuous stirred-tank reactors and distillation columns with recycle(CSTR-DC-recycle)are essential components in chemical processes.This paper proposes a method to establish a normal operating zone(NOZ)model to represent allowable variations of the CSTR-DC-recycle chemical processes.The NOZ is a geometric space containing all safe operating points of the CSTR-DC-recycle chemical processes,so that it is an effective model for process monitoring.The novelty of the proposed method is to establish the NOZ model based on boundary points.The boundary points make it possible to capture the actual geometric space irrespective of the space shape.In contrast,existing methods represent the NOZ of processes by fixed mathematical models such as ellipsoidal and convex-hull models;they are not suitable for the CSTR-DC-recycle chemical processes whose NOZs cannot be exactly defined by fixed mathematical structures.Simulated case studies based on Aspen Hysys software are given to illustrate the proposed method. 展开更多
关键词 Chemical processes Grey-box model Normal operating zone Bayesian estimation Model uncertainty measurement Boundary points
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