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驱控一体的旋拧式果实采摘执行器设计与试验

农机化研究 2025年第3期47卷 48-55页

作者：严童杰冯青春郭鑫杨宁江苏大学电气信息工程学院江苏镇江212000 北京市农林科学院智能装备技术研究中心北京100097 国家农业智能装备工程技术研究中心北京100097 农业智能装备技术北京市重点实验室北京100097

针对果园智能化采收作业需要,设计了支持总线扩展的驱控一体旋拧采摘末端执行器,旨在为多臂并行采摘机器人研发提供支撑。在对标准苹果树果实物理形态统计分析基础上,结合人工采摘方法,提出了“吸附-夹持-旋拧”的采摘机械操作方法,并... 详细信息

针对果园智能化采收作业需要,设计了支持总线扩展的驱控一体旋拧采摘末端执行器,旨在为多臂并行采摘机器人研发提供支撑。在对标准苹果树果实物理形态统计分析基础上,结合人工采摘方法,提出了“吸附-夹持-旋拧”的采摘机械操作方法,并设计了基于双舵机驱动的紧凑型采摘执行机构,对其吸盘、夹持和旋拧电机的关键参数进行了优化设计。面向多执行并行采摘需要,设计了基于CANopen通讯的采摘操作驱动器,实现了多执行器的总线扩展。通过现场试验对执行器作业性能进行了测试,结果表明:果实大小在60~100 mm之间,采摘成功率可达到90%,吸盘最优停留时间为1.00 s,吸盘最优接近距离为1.0 mm,最优旋拧角度为360°。

关键词：采摘机器人驱控一体旋拧采摘 CANopen

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工科专业课课程思政的学理自洽与建构理路

林区教学 2025年第1期 24-28页

作者：闫泽陆郭燚上海海事大学物流工程学院上海201306

思政价值的隐匿属性为工科专业核心课“三全育人”的实施带来较大难度。教师对课程思政学理性的认知差异和实践差距让潜隐价值的具象化难以合理消解。为此,以“电力系统分析基础”课程为例,通过理念辩误,明确知识与价值同向同频的逻辑... 详细信息

思政价值的隐匿属性为工科专业核心课“三全育人”的实施带来较大难度。教师对课程思政学理性的认知差异和实践差距让潜隐价值的具象化难以合理消解。为此,以“电力系统分析基础”课程为例,通过理念辩误,明确知识与价值同向同频的逻辑自洽。阐释工科思政“关键在教师,核心在内容,成效在学生”的基本方略。从师资培训、元素共议、学生评价角度探索课程思政的实施路径。

关键词：课程思政学理思政元素工科专业课

SEMI-IMPLICIT SPECTRAL DEFERRED CORRECTION METHODS BASED ON SECOND-ORDER TIME INTEGRATION SCHEMES FOR NONLINEAR PDES

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Journal of Computational Mathematics 2024年第1期42卷 111-133页

作者： Ruihan guo yan Xu School of Mathematics and Statistics Zhengzhou UniversityZhengzhou 450001China School of Mathematical Sciences University of Science and Technology of ChinaHefei 230026China

In[20],a semi-implicit spectral deferred correction(SDC)method was proposed,which is efficient for highly nonlinear partial differential equations(PDEs).The semi-implicit SDC method in[20]is based on first-order time integration methods,which are corrected iteratively,with the order of accuracy increased by one for each additional *** this paper,we will develop a class of semi-implicit SDC methods,which are based on second-order time integration methods and the order of accuracy are increased by two for each additional *** spatial discretization,we employ the local discontinuous Galerkin(LDG)method to arrive at fully-discrete schemes,which are high-order accurate in both space and *** experiments are presented to demonstrate the accuracy,efficiency and robustness of the proposed semi-implicit SDC methods for solving complex nonlinear PDEs.

关键词： Spectral deferred correction method Nonlinear PDEs Local discontinuous Galerkin method Second-order scheme

Circulating circRNA expression profile and its potential role in late recurrence of paroxysmal atrial fibrillation post catheter ablation

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Journal of Geriatric Cardiology 2023年第11期20卷 788-800页

作者： Shan-Shan LIU Hong-yang guo Jian ZHU Jin-Ling MA Sai-Zhe LIU Kun-lun HE Su-yan BIAN Department of Cardiology the Second Medical CenterNational Clinical Research Center of Geriatric DiseaseBeijing Key Laboratory of Chronic Heart Failure Precision MedicineChinese PLA General HospitalBeijingChina Department of Cardiology the Six Medical CenterChinese PLA General HospitalBeijingChina Medical Big Data Research Center Medical Innovation Research DepartmentBeijing Key Laboratory of Chronic Heart Failure Precision MedicineChinese PLA General HospitalBeijingChina

BACKGROUND Catheter-based pulmonary vein isolation(PVI) is an effective and well-established intervention for symptomatic paroxysmal atrial fibrillation(PAF). Nevertheless, late recurrences of atrial fibrillation(LRAF) occurring during 3 to 12months are common, and the underlying mechanisms remain elusive. Circular RNAs(circ RNAs) in atrial tissue have been linked to the pathophysiological mechanisms and progression of PAF in a few studies. However, their expression patterns in peripheral blood and regulatory function in LRAF are not *** In the present study, the expression profile of circulating circ RNAs in three paired nonvalvular PAF patients with or without LRAF was investigated by high-throughput sequencing and validated by quantitative real-time polymerase chain reaction(q RT-PCR). Bioinformatics analyses, including Gene Ontology(GO), Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway analysis, and circ RNA/mi RNA regulatory network, were performed to predict the functions and potential regulatory roles of differentially expressed(DE) circ *** A total of 12,834 circ RNAs, comprising 5,491 down-regulated and 7,343 up-regulated circ RNAs, were found to be DE in blood smaples from the two groups in peripheral blood between LRAF and non-recurrence control individuals. The most enriched GO categories in terms of molecular function, biological process, and cellular component features were catalytic activity,cellular metabolic process, and intracellular part, respectively. The KEGG enrichment study revealed that the most important metabolic process controlled by DE circ RNAs is endocytosis. In the circ RNA/micro RNAs interaction network, four up-regulated circ RNAs(hsa_circ_0002665, hsa_circ_0001953, hsa_circ_0003831, and hsa_circ_0040533) and one down-regulated circ RNA(hsa_circ_0041103) were predicted to play potential regulatory roles in the pathogenesis of *** This investigation discovered the expression pattern of circulating c

关键词： atrial fibrillation paroxysmal

Fabrication of supported acid catalytic composite fibers by a simple and low-cost method and their application on the synthesis of liquid biofuel 5-ethoxymethylfurfural

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Green Energy & Environment 2022年第1期7卷 165-171页

作者： Yinhua yan Huiqin guo Kexin Li Liushui yan Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle NanChang Hangkong UniversityNanChang330063China National-Local Joint Engineering Research Center of Heavy Metals Polluants Control and Resource Utilization NanChang Hangkong UniversityNanChang330063China

In this paper,sulfonic groups functionalized annealed bio-based carbon microspheres loaded polytetrafluoroethylene(A-BCMSs-SO_(3)H@PTFE)fibers with high activity,high stability,and easy regeneration were successfully fabricated by a simple method using low-cost raw *** characterization results showed that the annealed biomass carbon microspheres derived from waste Camellia oleifera shells were evenly distributed on the polytetrafluoroethylene fibers and the sulfonic groups can be successfully loaded on the surface of annealed biomass carbon microspheres by room temperature ***,the as-prepared A-BCMSs-SO_(3)H@PTFE fibers were applied to the acidcatalyzed synthesis of liquid biofuel *** catalytic experiment results indicated that the annealing temperature and time during catalyst preparation have a significant effect on the activity and selectivity of A-BCMSs-SO_(3)H@PTFE *** results of catalytic reaction kinetics showed that the yield of 5-ethoxymethylfurfural can reach more than 60%after 72 h of acid-catalyzed *** stability test showed that the as-prepared A-BCMSs-SO_(3)H@PTFE fibers still maintained a stable acid catalytic activity after four recycles.

关键词： Acid catalysis Waste Camellia oleifera shells Sulfonic groups Polytetrafluoroethylene fibers 5-Ethoxymethylfurfural

Forecasting Method of Stock Market Volatility in Time Series Data Based on Mixed Model of ARIMA and XGBoost

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China Communications 2020年第3期17卷 205-221页

作者： yan Wang Yuankai guo College of Computer and Communication LanZhou University of TechnologyLanzhou 730050China

Stock price forecasting is an important issue and interesting topic in financial *** reasonable and accurate forecasts have the potential to generate high economic benefits,many researchers have been involved in the study of stock price *** this paper,the DWT-ARIMAGSXGB hybrid model is ***,the discrete wavelet transform is used to split the data set into approximation and error *** the ARIMA(0,1,1),ARIMA(1,1,0),ARIMA(2,1,1)and ARIMA(3,1,0)models respectively process approximate partial data and the improved xgboost model(GSXGB)handles error partial ***,the prediction results are combined using wavelet *** to the experimental comparison of 10 stock data sets,it is found that the errors of DWT-ARIMA-GSXGB model are less than the four prediction models of ARIMA,XGBoost,GSXGB and *** simulation results show that the DWT-ARIMA-GSXGB stock price prediction model has good approximation ability and generalization ability,and can fit the stock index opening price *** the proposed model is considered to greatly improve the predictive performance of a single ARIMA model or a single XGBoost model in predicting stock prices.

关键词： hybrid model discrete wavelet transform ARIMA XGBoost,grid search stock price forecast

Urban Resilience in Post-Disaster Reconstruction: Towards a Resilient Development in Sichuan,China

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International Journal of Disaster Risk Science 2012年第1期3卷 45-55页

作者： yan guo School of Doctorate Studies University IUAV of Venice(Istituto Universitàdi Architettura di Venezia)30125 VeniceItaly

This article discusses the post-disaster urban resilience design framework in the case of post-disaster urban reconstruction in Sichuan after the Great Sichuan Earthquake(also known as the Wenchuan Earthquake) in May 2008 in China. The focus is on three main aspects of post-disaster urban reconstruction: sociospatial coherence,temporal continuity,and multistakeholder integration and communication. Critical interpretation of the government-guided reconstruction reveals that reconstruction was limited to the generic production and implementation of top-down planning. From the perspective of urban resilience,and through an alternative design scenario developed in this research,this article highlights an urban resilience design framework based on postdisaster development in the Sichuan city of Dujiangyan. By identifying the deficiencies of the governmental reconstruction where in many aspects resilience has not been considered,and by proposing the alternative where resilience has been considered to develop a better living,this research seeks to integrate urban resilience as a key aspect in the Sichuan reconstruction and as essential for developing the postdisaster city towards a more coherent,sustainable,and integral urban future.

关键词： China. disaster urban

Formation and evolution of supercritical geofluid

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Science China Earth Sciences 2025年第1期68卷 39-51页

作者： Huaiwei NI Yilin XIAO Xiaolin XIONG Xiandong LIU Chunxiao GAO Yi-Xiang CHEN Yunguo LI Wan-Cai LI Xuan guo yang-yang WANG Dong-Bo TAN Li ZHANG State Key Laboratory of Lithospheric and Environmental Coevolution University of Science and Technology of China Deep Space Exploration Laboratory/School of Earth and Space Sciences University of Science and Technology of China Guangzhou Institute of Geochemistry Chinese Academy of Sciences School of Earth Sciences and Engineering Nanjing University State Key Lab of Superhard Materials Jilin University

In this work, we provide a comprehensive review on the formation, evolution, properties, and effects of supercritical geofluid. In Earth's interior, enhanced miscibility between H2O and silicate by the addition of special components or by the increase of pressure and temperature gives rise to supercritical geofluid with a significant amount of both H2O and silicate *** formation of supercritical geofluid in magmatic-hydrothermal systems, typified by pegmatite system, is governed by meltfluid critical curve. The formation of supercritical geofluid in metamorphic systems, typified by subducted slab, is governed by the second critical end point. Experimental results suggest that the presence of boron and fluorine in pegmatite system makes it possible to form supercritical geofluid at crustal depths, but the release of supercritical geofluid from subducted slab is withheld until almost 100 km depth. A major presence of both H2O and depolymerized structural units（monomers, dimers, etc.） endows supercritical geofluid with unique physical properties including low density, low elastic moduli, low viscosity, high diffusivity,and high electrical conductivity. Supercritical geofluid can effectively mobilize a variety of elements even including high field strength elements and heavy rare earth elements. The chemical signatures of supercritical geofluid can be inherited by metasomatized mantle and mantle-derived melts, and this could give an explanation of the oxidation of arc magmas. Phase separation of supercritical geofluid through the mechanism of spinodal decomposition leads to formation of a melt network. Multiphase fluid inclusions recovered from subduction zone rocks and pegmatites are possible relics of supercritical geofluid. Supercritical geofluid can cause electrical anomaly and low seismic velocity near the top of subducted slab, and can be linked with intermediate-focus earthquakes. Supercritical geofluid may have played a crucial role in the formation of pe

关键词： Supercritical geofluid Miscibility Subduction zone Pegmatite

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Dynamic Response Study of Steel Catenary Riser Based on Slender Rod Model

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China Ocean Engineering 2019年第1期33卷 57-64页

作者： LIU Zhen guo Hai-yan College of Engineering Ocean University of China

A numerical model of the steel catenary riser(SCR) is built based on the slender rod model. The slender rod model,which describes the behavior of the slender riser in terms of the center line position, can solve the geometrical nonlinearity effectively. In a marine environment, the SCR is under the combined internal flow and external loads,such as wave and current. A general analysis considers only the inertial force and the drag force caused by the wave and current. However, the internal flow has an effect on the SCR; it is essential to explore the dynamic response of the SCR with the internal flow. The SCR also suffers the lift force and the fluctuating drag force because of the current. Finite element method is utilized to solve the motion equations. The effects of the internal flow, wave and current on the dynamic response of the SCR are considered. The results indicate that the increase of the internal flow density leads to the decrease of the displacement of the SCR, while the internal flow velocity has little effect on the SCR. The displacement of the SCR increases with the increase of the wave height and period. And the increasing wave period results in an increase in the vibration period of the SCR. The current velocity changes the displacements of the SCR in x-and z-directions. The vibration frequency of the SCR in y-direction increases with the increase of the current velocity.

关键词： steel catenary riser slender rod model internal flow dynamic response