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Analysis and Optimization of a Spatial Parallel Mechanism for a New 5-DOF Hybrid Serial-Parallel Manipulator

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Chinese Journal of Mechanical Engineering 2018年第3期31卷 60-68页

作者： Dong-Sheng Zhang Yun-Dou Xu jian-tao yao Yong-Sheng Zhao Parallel Robot and Mechatronic System Laboratory of Hebei Province Yanshan University Key Laboratory of Advanced Forging & Stamping Technology and Science of Ministry of National Education Yanshan University

Hybrid manipulators have potentially application in machining industries and attract extensive attention from many researchers on the basis of high sti ness and high dexterity. Therefore,in order to expand the application prospects of hybrid manipulator,a novel 5?degree?of?freedom(DOF) hybrid serial?parallel manipulator(HSPM) is proposed. Firstly,the design plan of this manipulator is introduced. Secondly,the analysis of this manipulator is carried out in detail,including kinematics analysis,statics analysis,and workspace analysis. Especially,an amplitude equivalent method of disposing the over?constrained force/couple to the non?overconstrained force/couple is used in the statics analysis. Then,three performance indices are used to optimize the PM. Two of them have been widely used,and the third one is a new index which considers the characteristics of the actuated force. Based on the performance indices,the performance atlas is drawn and the optimal design of the PM is investigated. In order to satisfy the anticipant kinetic characteristics of the PM,the verification of the optimized physical dimension is done and the workspace based on the optimized physical dimension is carried out. This paper will lay good theoretical foundations for application of this novel HSPM and also can be applied to other hybrid manipulators.

关键词： Parallel mechanism Performance indices Optimal design Performance atlas

Design and motion analysis of reconfigurable wheel-legged mobile robot

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Defence Technology（防务技术） 2022年第6期18卷 1023-1040页

作者： Shuo Zhang jian-tao yao Ying-bin Wang Zi-sheng Liu Yun-dou Xu Yong-sheng Zhao School of Mechanical Engineering Yanshan UniversityHebeiChina

An adaptive wheel-legged shape reconfigurable mobile robot,based on a scissor-like mechanism,is proposed for an obstacle detecting and surmounting robot,moving on complex *** robot can dynamically adjust its own shape,according to the environment,realizing a transformation of wheel shape into leg shape and vice *** wheel-legged mechanism has one degree of freedom,which means that only the relative motion of the inner and outer discs is needed to achieve the transformation of the shape into a wheel or a ***,the force analysis of the conversion process of the wheel-legged mechanism is carried out,while the relationship between the driving torque and the friction factor in the non-conversion trigger stage and in the conversion trigger stage is *** results showed that the shape conversion can be better realized by increasing the friction factor of the trigger ***,the kinematics analysis of the robot,including climbing the obstacles,stairs and gully,is carried *** motion of the spokes tip is obtained,in order to derive the folding ratio and the surmountable obstacle height of the wheel-legged *** parameters of the wheel-legged structure are optimized,to obtain better stability and obstacle climbing ***,a dynamic simulation model is established by ADAMS,to verify the obstacle climbing performance and gait rationality of the robot,in addition to a prototype *** results showed that the surmountable obstacle height of the robot is about3.05 times the spoke *** robot has the stability of a traditional wheel mechanism and the obstacle surmount performance of a leg mechanism,making it more suitable for field reconnaissance and exploration missions.

关键词： Mobile robots Scissor mechanism Kinematics ADAMS simulation Obstacle surmounting

Müller cells are activated in response to retinal outer nuclear layer degeneration in rats subjected to simulated weightlessness conditions

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Neural Regeneration Research 2025年第7期20卷 2116-2128页

作者： Yuxue Mu Ning Zhang Dongyu Wei Guoqing Yang Lilingxuan yao Xinyue Xu Yang Li Junhui Xue Zuoming Zhang tao Chen Aerospace Clinical Medical Center School of Aerospace MedicineAir Force Medical UniversityXi’anShaanxi ProvinceChina Department of Aviation Medicine Xijing HospitalAir Force Medical UniversityXi’anShaanxi ProvinceChina Department of Emergency Medicine Wuhan No.1 HospitalWuhanHubei ProvinceChina Third Regiment School of Basic MedicineAir Force Medical UniversityXi’anShaanxi ProvinceChina Fourth Regiment School of Basic MedicineAir Force Medical UniversityXi’anShaanxi ProvinceChina

A microgravity environment has been shown to cause ocular damage and affect visual acuity,but the underlying mechanisms remain ***,we established an animal model of weightlessness via tail suspension to examine the pathological changes and molecular mechanisms of retinal damage under *** 4 weeks of tail suspension,there were no notable alterations in retinal function and morphology,while after 8 weeks of tail suspension,significant reductions in retinal function were observed,and the outer nuclear layer was thinner,with abundant apoptotic *** investigate the mechanism underlying the degenerative changes that occurred in the outer nuclear layer of the retina,proteomics was used to analyze differentially expressed proteins in rat retinas after 8 weeks of tail *** results showed that the expression levels of fibroblast growth factor 2(also known as basic fibroblast growth factor)and glial fibrillary acidic protein,which are closely related to Müller cell activation,were significantly *** addition,Müller cell regeneration and Müller cell gliosis were observed after 4 and 8 weeks,respectively,of simulated *** findings indicate that Müller cells play an important regulatory role in retinal outer nuclear layer degeneration during weightlessness.

关键词： glial fibrous acidic protein gliosis Müller cells nerve growth factor neural differentiation neurodegeneration proteomic retinal degeneration retinal outer nuclear layer simulated weightlessness

Recent progress in the applications of presynaptic dopaminergic positron emission tomography imaging in parkinsonism

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Neural Regeneration Research 2025年第1期20卷 93-106页

作者： Yujie Yang Xinyi Li Jiaying Lu Jingjie Ge Mingjia Chen Ruixin yao Mei Tian jian Wang Fengtao Liu Chuantao Zuo Key Laboratory of Arrhythmias Ministry of EducationDepartment of Medical GeneticsShanghai East HospitalSchool of MedicineTongji UniversityShanghaiChina Department of Neurology National Research Center for Aging and MedicineNational Center for Neurological Disordersand State Key Laboratory of Medical NeurobiologyHuashan HospitalFudan UniversityShanghaiChina Department of Nuclear Medicine&PET Center National Center for Neurological Disordersand National Clinical Research Center for Aging and MedicineHuashan HospitalFudan UniversityShanghaiChina International Human Phenome Institutes(Shanghai) ShanghaiChina Human Phenome Institute Fudan UniversityShanghaiChina

Nowadays,presynaptic dopaminergic positron emission tomography,which assesses deficiencies in dopamine synthesis,storage,and transport,is widely utilized for early diagnosis and differential diagnosis of *** review provides a comprehensive summary of the latest developments in the application of presynaptic dopaminergic positron emission tomography imaging in disorders that manifest *** conducted a thorough literature search using reputable databases such as PubMed and Web of *** criteria involved identifying peer-reviewed articles published within the last 5 years,with emphasis on their relevance to clinical *** findings from these studies highlight that presynaptic dopaminergic positron emission tomography has demonstrated potential not only in diagnosing and differentiating various Parkinsonian conditions but also in assessing disease severity and predicting ***,when employed in conjunction with other imaging modalities and advanced analytical methods,presynaptic dopaminergic positron emission tomography has been validated as a reliable in vivo *** validation extends to screening and exploring potential neuropathological mechanisms associated with dopaminergic *** summary,the insights gained from interpreting these studies are crucial for enhancing the effectiveness of preclinical investigations and clinical trials,ultimately advancing toward the goals of neuroregeneration in parkinsonian disorders.

关键词： aromatic amino acid decarboxylase brain imaging dopamine transporter Parkinson’s disease parkinsonism positron emission tomography presynaptic dopaminergic function vesicle monoamine transporter type 2

EBD-YOLO：a lightweight auxiliary driving detection algorithm based on YOLOv5

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Optoelectronics Letters 2025年

作者： SUN Lianshuai SHI tao DING yao LI Song Tianjin Key Laboratory for Control Theory and Applications in Complicated Systems， School of Electrical Engineer-ing and Automation， Tianjin University of Technology College of Electrical Engineering， North China University of Science and Technology

A lightweight road-assistant detection algorithm， EBD-YOLO， based on YOLOv5s is proposed to address the problems of high model complexity， computation cost， and difficulty in deployment on resource-limited embedded terminals in existing assisted driving detection algorithms. First， lightweight Transformer model EfficientViT was used as the backbone feature extraction network of YOLOv5s model to reduce network parameters and calculation costs. Secondly， a Focal-GIoU Loss function is proposed for bounding box regression to accelerate model convergence and reduce loss. Thirdly， the feature pyramid structure is improved to a weighted bi-directional feature pyramid network (BiFPN) to enhance localization and semantic features. Then， a dynamic head framework is added to unify the attention mechanism with the object detection head to improve its performance. Finally， a Soft-CIoU＿NMS algorithm is proposed in the post-processing stage to enhance occluded targets' localization and detection ability and reduce the missed detection rate. We conducted experiments on the KITTI and BDD100K datasets for autonomous driving， and the results showed that the EBD-YOLO model reduced in size by 38.4% and 37.2%， respectively. In comparison， the computational cost was reduced by 48.1%. As measured by mAP@0.5， the detection accuracy improved by 0.5% and 5.8%， respectively， and mAP@0.5:0.95 improved by 2.8% and 7%， respectively. These improvements satisfied the requirements for deployment on embedded terminals in cars.

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含源项非定常非线性对流扩散方程的三次样条四阶差分格式

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水动力学研究与进展（A辑） 1994年第5期9卷 599-602页

作者：林建国许维德陶尧森上海交通大学船舶及海洋工程系上海200030 华南理工大学海洋工程系广州510641

本文提出一种新的求解含源项,非定常、非线性对流扩散方程的数值方法。首先,将方程在网格域内线性化,再利用变换将对流扩散方程转化为扩散方程,结合具有四阶精度的三次样条公式,最终将方程离散为二层三节点的无条件稳定差分格式,其推导... 详细信息

本文提出一种新的求解含源项,非定常、非线性对流扩散方程的数值方法。首先,将方程在网格域内线性化,再利用变换将对流扩散方程转化为扩散方程,结合具有四阶精度的三次样条公式,最终将方程离散为二层三节点的无条件稳定差分格式,其推导过程简便,精度为时间二阶,空间四阶。

关键词：非线性非定常对流扩散方程样条差分水力学

Clinicopathological differences between patients with schistosomal appendicitis and non schistosomal appendicitis:A retrospectively study of past ten years

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World Journal of Clinical Cases 2025年第2期13卷 24-32页

作者： Xiao-Yi Wang yao Hao Zi-jian Wang Xiu-Liang Xu jiang-Hua Yang Department of Infectious Diseases The First Affiliated of Wannan Medical CollegeWuhu 241001Anhui ProvinceChina

BACKGROUND Chronic schistosomiasis causes multiple organ and multiple system diseases,especially the digestive *** eggs are mainly deposited in the stomach,liver and colorectal,but a few eggs are deposited in the appendix and cause *** present,there are few studies on schistosomal *** To explore the differences in epidemiological,clinical and pathological characteristics between schistosomal appendicitis and non-schistosomal appendicitis over the past decade in order to assess the impact of schistosomiasis on *** The differences of general data,clinical data and laboratory examination data of patients with appendicitis from October 2013 to October 2023 were retrospectively *** patients were divided into two groups for *** were 136 patients in schistosomal appendicitis group and 5418 patients in non-schistosomal appendicitis *** Schistosomal appendicitis accounted for 2.45%of all patients with appendicitis,and the annual proportion in the past decade was 2.2%,2.9%,1.8%,1.9%,3.4%,3.1%,1.9%,1.6%,3%,2.6%,*** prevalence of schistosomal appendicitis was middle-aged and elderly males,with an average age of 61.73±15.335 *** main population of non-schistosomal appendicitis was middle-aged men,with an average age of 35.8±24.013 years(P<0.001).The distribution of pathological types of appendicitis was different between the two groups(P<0.001).The incidence of acute suppurative appendicitis in non-schistosomal appendicitis was higher than that in schistosomal appendicitis[odds ratio(OR)=0.504;95%confidence interval(CI):0.349-0.728;P<0.001].The proportion of acute attack of chronic appendicitis in schistosomal appendicitis was higher than that in non-schistosomal appendicitis(OR=2.614;95%CI:1.815-3.763;P<0.001).The proportion of schistosomal appendicitis patients complicated with colorectal cancer was higher than that of nonschistosomal appendicitis patients(OR=5.087;95%CI:1.427-

关键词： Schistosomal appendicitis Schistosomiasis Appendix Colorectal cancer Clinicopathological characteristics

基于消费者介入理论的在线购买行为影响要素及预测研究

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管理工程学报 2025年第2期39卷 144-161页

作者：陶婉琼王子卓王健浙江工商大学统计数据工程技术与应用协同创新中心浙江大学管理学院浙江吉利控股集团有限公司浙江工商大学管理工程与电子商务学院浙江工商大学现代商贸研究中心

本文主要研究消费者在线购买行为的影响。本文首先从参与强度、消费者类型、购物流程类型和广告点击次数四个维度定义了表征消费者在线购买决策心理特征的消费者介入水平,然后基于消费者介入理论分别从群体水平和个体水平的视角分析消... 详细信息

本文主要研究消费者在线购买行为的影响。本文首先从参与强度、消费者类型、购物流程类型和广告点击次数四个维度定义了表征消费者在线购买决策心理特征的消费者介入水平,然后基于消费者介入理论分别从群体水平和个体水平的视角分析消费者介入水平维度对其购物数量和购物时间间隔等行为的影响。以此为基础,本文采用多种机器学习方法构建了消费者在线购买行为预测模型。通过对不同预测模型的比较发现,神经网络回归模型对购物数量预测的误差性最小和拟合度最高,而梯度提升回归模型对购物时间间隔预测的性能最好。同时,通过特征变量的重组设置对比实验,本文验证了在购买行为预测模型中引入介入水平维度的有效性和合理性。研究结果揭示了消费者介入水平对在线购买行为的影响规律,不仅丰富了相关理论,而且对网购平台和商家精确预测消费者购买行为、优化服务策略等方面具有重要的指导意义。

关键词：决策科学电子商务消费者介入在线购买行为预测模型

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Metastable seed-crystals: epitaxial growth of branched-array organic heterostructure nanowires

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Science China Chemistry 2025年

作者： Jin Feng Zhen-Yu Geng Ting-yao Song Ying-Xin Ma Chuan-Zeng Wang Wei Zhang Hong-tao Lin Jin Zhou Shu-Ping Zhuo Shu-Hai Chen Xue-Dong Wang School of Chemistry and Chemical Engineering Shandong University of Technology Institute of Functional Nano & Soft Materials (FUNSOM) Jiangsu Key Laboratory for Carbon-Based Functional Materials & DevicesSoochow University College of Chemistry and Chemical Engineering Hunan Normal University

Tunable light–matter interactions are exhibited by organic low-dimensional crystals, making these crystals a promising platform for organic photonics. However, the precise synthesis of organic low-dimensional crystals remains challenging due to the stochastic nature of molecular nucleation processes. Herein, the directed nucleation process is driven by the introduction of metastable seed-crystals as the trunk, which ultimately leads to branched-array organic heterostructures. The successful formation of organic heterostructures with high-density branched arrays is attributed to the highest attachment energy (Eatt（023）=-104.25 kcal mol-1) of the exposed （023） crystal plane during the seed-crystal growth route. Significantly, these as-prepared heterostructures inherently have an ultralow lattice mismatch ratio η of 0.7%between trunk and branch, which contributes to the multi-channel photon transportation. Therefore, this work provides valuable insights into a versatile synthetic strategy for accessing low-dimensional heterostructures for integrated optoelectronics.

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