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Visual perception driven 3D building structure representa tion from airborne laser scanning point cloud

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Virtual Reality & Intelligent Hardware 2020年第3期2卷 261-275页

作者： pingbo hu Bisheng YANG School of Geomatics and Urban Spatial Beijing University of Civil Engineering and ArchitectureBeijing 102616China State Key Laboratory of Information Engineering in Surveying Mapping and Remote SensingWuhan UniversityWuhan 430079China

Background Three-dimensional(3D)building models with unambiguous roof plane geometry parameters,roof structure units,and linked topology provide essential data for many applications related to human activities in urban *** task of 3D reconstruction from point clouds is still in the development phase,especially the recognition and interpretation of roof topological *** This study proposes a novel visual perception-based approach to automatically decompose and reconstruct building point clouds into meaningful and simple parametric structures,while the associated mutual relationships between the roof plane geometry and roof structure units are expressed by a hierarchical topology ***,a roof plane extraction is performed by a multi-label graph cut energy optimization framework and a roof structure graph(RSG)model is then constructed to describe the roof topological geometry with common adjacency,symmetry,and convexity ***,a progressive roof decomposition and refinement are performed,generating a hierarchical representation of the 3D roof structure ***,a visual plane fitted residual or area constraint process is adopted to generate the RSG model with different levels of *** Two airborne laser scanning datasets with different point densities and roof styles were tested,and the performance evaluation metrics were obtained by International Society for Photogrammetry and Remote Sensing,achieving a correctness and accuracy of 97.7%and 0.29m,*** The standardized assessment results demonstrate the effectiveness and robustness of the proposed approach,showing its ability to generate a variety of structural models,even with missing data.

关键词： Point cloud Visual perception rules Building Structural 3D reconstruction

Investigation of mechanical and electrical characteristics of selfsensing pneumatic torsional actuators

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Science China(Technological Sciences) 2024年第1期67卷 130-142页

作者： XIAO Wei hu DeAn hu GuoLiang XIAO Yihua Key Laboratory of Conveyance and Equipment Ministry of EducationEast China Jiaotong UniversityNanchang 330013China Key Laboratory of Advanced Design and Simulation Techniques for Special Equipment Ministry of EducationHunan UniversityChangsha 410082China

Soft pneumatic actuators are one of the most promising actuation for soft robots,and great achievements have been *** it remains challenging to endow sensing capabilities to pneumatic actuators,especially for the sensing ability originating directly from the actuator ***,a self-sensing pneumatic torsional actuator(SPTA)is designed based on the electromagnetic induction effect and magnetically responsive *** SPTA can generate feedback voltage and current with the deformation,in which the sensing function comes from its inherent *** investigate the mechanical and electrical characteristics,an experimental platform and a finite element model are established,*** find that the torsion angle and output torque increase in nonlinear with the actuating *** maximum torsion angle is 66.35°,which is 84.34%of that for the actuator fabricated by pure *** maximum output torque(24.9 N mm)improves by 23.19%compared with the actuator made by pure *** regards the electrical characteristics,the maximum feedback voltage and current are 2.90μV and 29.50 nA when the SPTA is actuated by a pressure of−40 *** also demonstrate that the relationship between the torsion angle and the magnetic flux change is approximately ***,the number of turns of wires,magnetic powders contents,and magnetic direction on the feedback voltage and current are *** show that the feedback voltage and current can be enhanced by increasing the number of turns and magnetic powders *** envision that the SPTA would be promising for soft robots to realize their accuracy control and intelligentization.

关键词： pneumatic torsional actuators self-sensing feedback voltage finite element modeling soft robots

R-matrix for the 8-Dimensional Spin Representation of Uq(so7)

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Acta Mathematica Sinica,English Series 2024年第2期40卷 485-497页

作者： Hong Mei hu Nai Hong hu School of Mathematical Sciences Suzhou University of Science and TechnologySuzhou 215009P.R.China School of Mathematical Sciences MOE Key Laboratory of Mathematics and Engineering Applications&Shanghai Key Laboratory of PMMPEast China Normal UniversityShanghai 200241P.R.China

The purpose of the paper is to describe the solution to the quantum Yang-Baxter equation associated with the 8-dimensional spin representation Tsp of Uq(so7).The self-duality of Tsp and the symmetry of the corresponding braiding matrix are ***,the minimal polynomial of the braiding R-matrix of Tsp is presented explicitly in an ingenious method by taking advantage of nice features of the spin representation Tsp.

关键词： Braiding R-matrix spin module minimal polynomial

Mapping out the reaction network of humin formation at the initial stage of fructose dehydration in water

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Green Energy & Environment 2024年第6期9卷 1016-1026页

作者： Xing Fu Yexin hu Ping hu hui Li Shuguang Xu Liangfang Zhu Changwei hu Key Laboratory of Green Chemistry and Technology Ministry of EducationCollege of ChemistrySichuan UniversityChengduSichuan610064China State Key Laboratory of Southwestern Chinese Medicine Resources Innovative Institute of Chinese Medicine and PharmacyChengdu University of Traditional Chinese MedicineChengduSichuan611137China

The formation of humins hampers the large-scale production of 5-hydroxymethylfurfural(HMF)in ***,a detailed reaction network of humin formation at the initial stage of fructose-to-HMF dehydration in water is delineated by combined experimental,spectroscopic,and theoretical *** bimolecular reaction pathways to build up soluble humins are *** is,the intermolecular etherification of β-furanose at room temperature initiates the C12 path,whereas the C-C cleavage of a-furanose at 130-150℃ leads to C11 path,and that of open-chain fructose at 180℃ to C11' *** successive intramolecular dehydrations and condensations of the as-formed bimolecular intermediates lead to three types of soluble *** show that the C12 path could be restrained by using HCl or AlCl_(3) catalyst,and both the C12 and C110 paths could be effectively inhibited by adding THF as a co-solvent or accelerating heating rate via microwave heating.

关键词： Carbohydrates 5-hydroxymethylfurfural Reaction network Soluble humins Tautomer

A vertical track nonlinear energy sink

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Applied Mathematics and Mechanics(English Edition) 2024年第6期45卷 931-946页

作者： Meng LI hu DING Shanghai Key Laboratory of Mechanics in Energy Engineering School of Mechanics and Engineering ScienceShanghai Frontier Science Center of MechanoinformaticsShanghai UniversityShanghai 200444China

Eliminating the effects of gravity and designing nonlinear energy sinks(NESs)that suppress vibration in the vertical direction is a challenging task with numerous damping *** this paper,the dynamic design of a vertical track nonlinear energy sink(VTNES)with zero linear stiffness in the vertical direction is proposed and realized for the first *** motion differential equations of the VTNES coupled with a linear oscillator(LO)are *** the strong nonlinearity considered of the VTNES,the steady-state response of the system is analyzed with the harmonic balance method(HBM),and the accuracy of the HBM is verified *** this basis,the VTNES prototype is manufactured,and its nonlinear stiffness is *** damping effect and dynamic characteristics of the VTNES are studied theoretically and *** results show that the VTNES has better damping effects when strong modulation responses(SMRs)***,even for small-amplitude vibration,the VTNES also has a good vibration suppression *** sum up,in order to suppress the vertical vibration,an NES is designed and developed,which can suppress the vertical vibration within certain ranges of the resonance frequency and the vibration intensity.

关键词： track nonlinear energy sink(TNES) vertical direction gravity nonlinear stiffness harmonic balance method(HBM) vibration control

Effect of CO_(2) Opposing Multiple Jets on Thermoacoustic Instability and NO_(x) Emissions in a Lean-Premixed Model Combustor

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Journal of Thermal Science 2024年第1期33卷 207-221页

作者： ZHOU Hao hu Liubin Institute for Thermal Power Engineering State Key Laboratory of Clean Energy UtilizationZhejiang UniversityHangzhou 310027China

This paper experimentally studied the effect of CO_(2) opposing multiple jets on the thermoacoustic instability and NO_(x) emissions in a lean-premixed model *** feasibility was verified from three variables:the CO_(2) jet flow rate,hole numbers,and hole diameters of the *** indicate that the control effect of thermoacoustic instability and NO_x emissions show a reverse trend with the increase of open area ratio on the whole,and the optimal jet flow rate range is 1-4 L/min with CO_(2) opposing multiple *** this flow rate range,the amplitude and frequency of the dynamic pressure and heat release signals CH~* basically decrease as the CO_(2) flow rate increases,which avoids high-frequency and high-amplitude thermoacoustic *** amplitude-damped ratio of dynamic pressure and CH*can reach as high as 98.75% and 93.64% with an optimal open area ratio of 3.72%.NO_(x) emissions also decrease as the jet flow rate increases,and the maximum suppression ratio can reach 68.14%.Besides,the flame shape changes from a steep inverted "V" to a more flat "M",and the flame length will become shorter with CO_(2) opposing multiple *** research achieved the synchronous control of thermoacoustic instability and NO_(x) emissions,which could be a design reference for constructing a safer and cleaner combustor.

关键词： thermoacoustic instability lean-premixed model combustor CO_(2)opposing multiple jets open area ratio NO_(x)emissions

Outlier-resistant distributed fusion filtering for nonlinear discrete-time singular systems under a dynamic event-triggered scheme

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Frontiers of Information Technology & Electronic Engineering 2024年第2期25卷 237-249页

作者： Zhibin hu Jun hu Cai CHEN Hongjian LIU Xiaojian YI Department of Applied Mathematics Harbin University of Science and TechnologyHarbin150080China Heilongjiang Provincial Key Laboratory of Optimization Control and Intelligent Analysis for Complex Systems Harbin University of Science and TechnologyHarbin150080China School of Automation Harbin University of Science and TechnologyHarbin150080China School of Mathematics and Physics Anhui Polytechnic UniversityWuhu241000China School of Mechatronical Engineering Beijing Institute of TechnologyBeijing100081China Yangtze Delta Region Academy of Beijing Institute of Technology Jiaxing314003China Tangshan Research Institute Beijing Institute of TechnologyTangshan063099China

This paper investigates the problem of outlier-resistant distributed fusion filtering(DFF)for a class of multi-sensor nonlinear singular systems(MSNSSs)under a dynamic event-triggered scheme(DETS).To relieve the effect of measurement outliers in data transmission,a self-adaptive saturation function is ***,to further reduce the energy consumption of each sensor node and improve the efficiency of resource utilization,a DETS is adopted to regulate the frequency of data *** the addressed MSNSSs,our purpose is to construct the local outlier-resistant filter under the effects of the measurement outliers and the DETS;the local upper bound(UB)on the filtering error covariance(FEC)is derived by solving the difference equations and minimized by designing proper filter ***,according to the local filters and their UBs,a DFF algorithm is presented in terms of the inverse covariance intersection fusion *** such,the proposed DFF algorithm has the advantages of reducing the frequency of data transmission and the impact of measurement outliers,thereby improving the estimation ***,the uniform boundedness of the filtering error is discussed and a corresponding sufficient condition is ***,the validity of the developed algorithm is checked using a simulation example.

关键词： Distributed fusion filtering Multi-sensor nonlinear singular systems Dynamic event-triggered scheme Outlier-resistant filter Uniform boundedness

农村人力资源开发影响因素的维度结构及测量——基于中部省份实地调查的研究

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农业经济问题 2009年第7期30卷 73-79页

作者：胡平波江西财经大学信息管理学院南昌330013

通过文献回顾,本文概括出农村人力资源开发影响因素的维度结构,并在质化研究基础上利用两套独立样本数据分别进行探索性和验证性因素分析。研究表明,农村人力资源开发影响因素由四个维度构成,验证了本研究提出的理论框架。同时,本文还... 详细信息

通过文献回顾,本文概括出农村人力资源开发影响因素的维度结构,并在质化研究基础上利用两套独立样本数据分别进行探索性和验证性因素分析。研究表明,农村人力资源开发影响因素由四个维度构成,验证了本研究提出的理论框架。同时,本文还通过质化研究与指标的数据分析,开发出一套信度、效度良好的农村人力资源开发影响因素的维度测量指标体系。

关键词：农村人力资源开发影响因素维度结构结构方程

支持合作社生态化建设的区域生态农业创新体系构建研究

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农业经济问题 2018年第12期39卷 94-106页

作者：胡平波江西财经大学规制与竞争研究中心

合作社生态化建设有利于农村环保和农业可持续发展。通过区域生态农业创新体系构建,可以促使农民树立生态观念,推动生态农产品开发与组织生态文化建设,从而支持合作社生态化建设。政府主导是推动区域生态农业创新体系构建的关键,科研院... 详细信息

合作社生态化建设有利于农村环保和农业可持续发展。通过区域生态农业创新体系构建,可以促使农民树立生态观念,推动生态农产品开发与组织生态文化建设,从而支持合作社生态化建设。政府主导是推动区域生态农业创新体系构建的关键,科研院所与服务机构是促使生态技术创新与扩散的基础,企业与农村精英创新是支持合作社生态化建设的关键。有效的区域生态农业创新体系需要实现观念、技术与制度的协同创新,需要推动生态创新单元有效运行、创新成果实现与推广。以江西省芦溪县建设"国家现代农业示范区"分析为例发现,芦溪县域生态农业创新体系能够有效支持本地的生态农业创新活动,不断推动合作社生态化建设,实现芦溪县生态农业持续健康发展。

关键词：合作社生态化建设区域生态农业创新体系构建