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Processing limit maps for the stable deformation of dieless drawing

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International Journal of Minerals,Metallurgy and Materials 2011年第3期18卷 330-337页

作者： yong he Xue-feng Liu Jian-xin Xie Hong-gang Zhang Key Laboratory for Advanced Materials Processing （MOE） University of Science and Technology Beijing Beijing 100083 China State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing Beijing 100083 China

Tin bronze wires were produced by dieless drawing. The effects of heating power, the distance between cooler and heater as well as feeding speed on the diameter, the temperature field, and the deformation region profile of the wires were investigated. The results indicated that each processing parameter exhibited both lower and upper limits of stable deformation based on the criterion of stable deformation with the diameter fluctuation of ±0.05 mm. Both the temperature and its gradient of the deformation region increased with increasing heating power under stable deformation, but decreased with an increase in feeding speed. As the distance between cooler and heater increased, the temperature of the deformation region increased and the slope of the deformation region profile decreased. The processing limit map of stable deformation exhibited a closed curve and the unstable deformation consisted of wire breakage and diameter fluctuations.

关键词： tin bronze wire dieless drawing processing parameters turning method

硫化钠体系中异极矿表面的硫化特性及硫化产物解析

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Transactions of Nonferrous Metals Society of China 2024年第2期34卷 629-642页

作者：张嘎王美丽和永新王涵丰奇成昆明理工大学国土资源工程学院省部共建复杂有色金属资源清洁利用国家重点实验室昆明650093 昆明理工大学云南省战略金属矿产资源绿色分离与富集重点实验室昆明650093 内蒙古兴业矿业股份有限公司赤峰024028

通过多种分析检测方法揭示硫化钠体系中异极矿表面的硫化特性和机理,并对异极矿表面硫化产物进行分析测试。研究结果表明,硫化钠浓度对异极矿表面的硫化效果具有显著影响,即提高硫化钠浓度能促进矿浆溶液中硫组分与矿物表面反应,从而提... 详细信息

通过多种分析检测方法揭示硫化钠体系中异极矿表面的硫化特性和机理,并对异极矿表面硫化产物进行分析测试。研究结果表明,硫化钠浓度对异极矿表面的硫化效果具有显著影响,即提高硫化钠浓度能促进矿浆溶液中硫组分与矿物表面反应,从而提高异极矿表面硫化产物的含量及矿物表面的疏水性。XPS和ToF-SIMS分析表明,异极矿表面的硫化产物并非单一的硫化物,而是由硫化物(S^(2−))和多硫化物(S_(n)^(2−))组成,且矿物表面多硫化物含量随硫化钠浓度的增加而增加,从而增强异极矿表面硫化产物的活性。

关键词：硫化特性异极矿硫化钠浓度硫化锌组分多硫化物

Timesharing-tracking Framework for Decentralized Reinforcement Learning in Fully Cooperative Multi-agent System

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IEEE/CAA Journal of Automatica Sinica 2014年第2期1卷 127-133页

作者： Xin Chen Bo Fu yong he Min Wu School of Automation China University of Geosciences School of Information Science and Engineering Central South University

Dimension-reduced and decentralized learning i always viewed as an efficient way to solve multi-agent cooperative learning in high dimension. However, the dynamic environmen brought by the concurrent learning makes the decentralized learning hard to converge and bad in performance. To tackle thi problem, a timesharing-tracking framework(TTF), stemming from the idea that alternative learning in microscopic view results in concurrent learning in macroscopic view, is proposed in this paper, in which the joint-state best-response Q-learning(BRQ-learning) serves as the primary algorithm to adapt to the companions policies. With the properly defined switching principle, TTF makes all agents learn the best responses to others at different joint states. Thus from the view of the whole joint-state space, agents learn the optimal cooperative policy simultaneously. The simulation results illustrate that the proposed algorithm can learn the optimal joint behavior with les computation and faster speed compared with other two classica learning algorithms.

关键词： Multi-agent systems Learning (artificial intelligence) Switches Reinforcement learning Optimization Robots Games

Influence of UAV flight speed on droplet deposition characteristics with the application of infrared thermal imaging

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International Journal of Agricultural and Biological Engineering 2019年第3期12卷 10-17页

作者： Meiqiao Lv Shupei Xiao Yu Tang yong he Jinhua Polytechnic College Jinhua 321017ZhejiangChina College of Biosystems Engineering and Food Science Zhejiang UniversityHangzhou 310058China College of Automation Zhongkai University of Agriculture and EngineeringGuangzhou 510225China

A plant protection unmanned aerial vehicle(UAV)applied for spraying pesticide has the advantages of low cost,high efficiency and environmental protection.However,the complex and changeable farmland environment is not conductive to perform spray test effectively.It is therefore necessary to carry out spray test under controlled conditions.The current study aimed to illuminate the variation law of droplet deposition characteristics under different UAV flight speeds,and to verify the feasibility for applying infrared thermal imaging in detection of droplet deposition effects.A UAV simulation platform with an airborne spray system was established and an analysis program Droplet Analysis for dealing with water-sensitive paper was developed.The results showed that,when the flight speed was set at 0.3 m/s,0.5 m/s,0.7 m/s,0.9 m/s and 1 m/s,respectively,the droplet deposition density,droplet deposition coverage and arithmetic mean of droplet size D0 decreased as the UAV flight speed increased.On the contrary,the droplet diameter variation coefficient CV increased with the increase of UAV flight speed,resulting in the worse uniformity of sprayed droplet distribution as well.The results can provide a theoretical support for optimizing the spraying parameters of plant protection UAV,and demonstrate the practicability of infrared thermal imaging in evaluating the droplet deposition in the field of aerial spraying.

关键词： spray test UAV flight speed droplet deposition characteristics droplet analysis image processing infrared thermal imaging

Improved potential energy-shaping for port-controlled Hamiltonian systems

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控制理论与应用（英文版） 2012年第3期10卷 385-390页

作者： Liangcheng CAI yong he Min WU Jinhua She School of Information Science and Engineering Central South UniversityChangsha Hunan 410083China Hunan Engineering Laboratory for Advanced Control and Intelligent Automation Changsha Hunan 410083China School of the Computer Science Tokyo University of TechnologyTokyo 192-0982Japan

This paper investigates the asymptotical stabilization of port-controlled Hamiltonian （PCH） systems via the improved potential energy-shaping （IPES） method. First, a desired potential energy introduced by a transitive Hamiltonian function is added to the original kinetic energy to yield a desired Hamiltonian function. Second, an asymptotically stabilized controller is designed based on a new matching equation with the obtained Hamiltonian function. Finally, a numerical example is given to show the effectiveness of the proposed method.

关键词： Port-controlled Hamiltonian （PCH） systems Improved potential energy-shaping （IPES） Asymptoticalstabilization

The structural connectome in ADHD

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Psychoradiology 2021年第4期1卷 257-271页

作者： Xuan Bu Miao Cao Xiaoqi Huang yong he State Key Laboratory of Cognitive Neuroscience and Learning Beijing Normal UniversityBeijing 100875China Beijing Key Laboratory of Brain Imaging and Connectomics Beijing Normal UniversityBeijing 100875China IDG/McGovern Institute for Brain Research Beijing Normal UniversityBeijing 100875China Institute of Science and Technology for Brain-Inspired Intelligence Fudan UniversityShanghai 200433China Key Laboratory of Computational Neuroscience and Brain-Inspired Intelligence(Fudan University) Ministry of EducationShanghai 200433China Huaxi MR Research Center West China Hospital of Sichuan UniversityChengdu 610041China Chinese Institute for Brain Research Beijing 102206China

Attention-deficit/hyperactivity disorder(ADHD)has been conceptualized as a brain dysconnectivity disorder.In the past decade,noninvasive diffusion magnetic resonance imaging(dMRI)studies have demonstrated that individuals with ADHD have alterations in the white matter structural connectome,and that these alterations are associated with core symptoms and cognitive deficits in patients.This review aims to summarize recent dMRI-based structural connectome studies in ADHD from voxel-,tractography-,and network-based perspectives.Voxel-and tractography-based studies have demonstrated disrupted microstructural properties predominantly located in the frontostriatal tracts,the corpus callosum,the corticospinal tracts,and the cingulum bundle in patients with ADHD.Network-based studies have suggested abnormal global and local efficiency as well as nodal properties in the prefrontal and parietal regions in the ADHD structural connectomes.The altered structural connectomes in those with ADHD provide significant signatures for prediction of symptoms and diagnostic classification.These studies suggest that abnormalities in the structural connectome may be one of the neural underpinnings of ADHD psychopathology and show potential for establishing imaging biomarkers in clinical evaluation.However,given that there are inconsistent findings across studies due to sample heterogeneity and analysis method variations,these ADHD-related white matter alterations are still far from informing clinical practice.Future studies with larger and more homogeneous samples are needed to validate the consistency of current results;advanced dMRI techniques can help to generatemuchmore precise estimation of whitematter pathways and assure specific fiber configurations;and finally,dimensional analysis frameworks can deepen our understanding of the neurobiology underlying ADHD.

关键词： attention-deficit/hyperactivity disorder white matter diffusion MRI connectomics

能源费用托管型合同下嵌入视角的供应链合作减排决策研究

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中国管理科学 2024年第5期32卷 113-121页

作者：廖诺梁佩仪贺勇罗雪韵广东工业大学管理学院广东广州510520

研究能源费用托管型合同下节能服务公司(ESCO)提供嵌入式低碳服务的供应链合作减排决策问题。首先,分别建立无节能服务公司参与,以及基于能源费用托管型合同有节能服务公司参与的供应链合作减排博弈模型;其次,讨论两种情形下的减排效果... 详细信息

研究能源费用托管型合同下节能服务公司(ESCO)提供嵌入式低碳服务的供应链合作减排决策问题。首先,分别建立无节能服务公司参与,以及基于能源费用托管型合同有节能服务公司参与的供应链合作减排博弈模型;其次,讨论两种情形下的减排效果,分析供应链与节能服务公司合作减排的条件;最后,基于能源费用托管型合同,探讨嵌入式低碳服务对供应链减排决策的影响,具体分析相关参数对供应链最优决策的影响。结果表明:满足一定条件下,供应链才会选择与ESCO进行合作减排;当嵌入度(合同期内的等额现值系数与项目经济寿命期内的等额现值系数之比)达到某一既定值时,二者碳减排项目价值的关注开始趋于一致;高水平的嵌入度可实现较好的减排效果,且嵌入度与供应链的期望利润呈U型变动关系,与ESCO的期望利润呈正相关关系。

关键词：供应链合作减排嵌入式低碳服务嵌入度能源费用托管型

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基于RF-BiLSTM模型的河流水质预测

长江科学院院报 2024年第7期41卷 57-63,71页

作者：兰小机贺永兰武帅文江西理工大学土木与测绘工程学院江西赣州341000

水环境中过量的氮、磷和高锰酸盐会对流域造成严重污染,准确预测这三类指标的含量对流域污染治理具有重要意义。然而,现有的模型预测精度低,输入因子的选择缺乏数理依据。基于此,以邕江为研究区域,提出一种RF-BiLSTM的混合网络模型。该... 详细信息

水环境中过量的氮、磷和高锰酸盐会对流域造成严重污染,准确预测这三类指标的含量对流域污染治理具有重要意义。然而,现有的模型预测精度低,输入因子的选择缺乏数理依据。基于此,以邕江为研究区域,提出一种RF-BiLSTM的混合网络模型。该模型具有利用RF算法提取水质指标最优特征和利用BiLSTM模型提取输入数据的时间特征的优势,采用先降维后预测的方式对TN、TP和COD Mn进行预测,并将深度学习中的CNN、LSTM、BiLSTM和RF-LSTM作为基准模型与本研究所提模型作对比研究。研究结果表明,本研究模型预测TN、TP和COD Mn的平均绝对百分比误差(MAPE)分别达到了4.330%、6.781%和7.384%,均低于其他基准模型,预测结果具有较高的准确性和实用性,可为水环境的污染治理提供有效的技术支持。

关键词：水质预测特征选择随机森林双向长短时记忆神经网络深度学习

Why choose 3D bioprinting?Part II:methods and bioprinters

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Bio-Design and Manufacturing 2020年第1期3卷 1-4页

作者： yong he Zeming Gu Mingjun Xie Jianzhong Fu Hui Lin State Key Laboratory of Fluid Power and Mechatronic Systems School of Mechanical EngineeringZhejiang UniversityHangzhou 310027China Department of General Surgery Sir Run Run Shaw HospitalSchool of MedicineZhejiang UniversityHangzhou 310058China

Classification of 3D bioprinting As we mentioned in the last editorial,3D printing,also known as additive manufacturing,could be considered as the reverse process of potato cutting,automatically assembling sliced potato,shredded potato,diced potato to integrity[1].Generally speaking,cell-laden 3D bioprinting can be classified into three types:extrusion-based,droplet-based and photocuring-based bioprinting according to different printing principles.Extrusion-based bioprinting squeezes out continuous hydrogel fibers to set up structures;dropletbased bioprinting generates droplets as the basic unit for biofabrication;and photocuring-based bioprinting utilizes the characteristics of light-sensitive materials,to stack 3D models layer-by-layer.Different bioprinting approaches own diverse characteristics facing various scenarios and have specific requirements for bioinks.

关键词： printing utilize printer