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Evaluation and optimization analysis of high-speed rail network structure in Northeast China under the background of northeast revitalization

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Regional Sustainability 2021年第4期2卷 349-362页

作者： XU Shaojie wang fuyuan wang Kaiyong Key Laboratory of Regional Sustainable Development Modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing100101China University of Chinese Academy of Sciences Beijing100049China

The construction of high-speed rail(HSR)network has promoted the social-economic ties of cities,accelerated the compression of time and space,and changed the pattern of regional development.In this paper,with the adoption of the operation frequency data of HSR from 12306 website,and based on the HSR connection strength model and social network analysis model,as well as according to the HSR connection strength,HSR network density,centrality,agglomeration subgroup,and other indicators,we analyzed the characteristics of HSR network structure in Northeast China.Results show that the number of HSR cities in Northeast China is small,cities in HSR network generally exhibit weak connectivity,and the existence of HSR network marginalizes cities such as Ulanhot,Baicheng,and Songyuan,which significantly reduce the overall network connectivity of Northeast China.The overall centrality of HSR network in Northeast China is characterized by“one axis,four edges”;specifically,the one axis is located in Harbin-Dalian transportation line and the four edges are located on both sides of the main axis of Harbin-Dalian transportation line.Eight agglomeration subgroups(four double city subgroups and four multi city subgroups)have formed in Northeast China.The core status of Shenyang in HSR network is improved significantly,and“one axis and two wings”HSR network in Liaoning Province is improved significantly.With the gradual expansion of Chaoyang-Fuxin,Dandong-Benxi,and Jilin-Yanji branch networks,the“point axis”HSR network mode in Northeast China has gradually developed and matured.In the future,it is recommended to rely on eight agglomerating subgroups to encrypt HSR network structure,create secondary node central cities,and gradually build a new pattern of opening up in Northeast China.

关键词： Social network analysis High-speed rail network structure Operation frequency Intercity connection intensity Network density analysis Northeast China

Behavior of Pile Groups under Lateral Load

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China Ocean Engineering 1991年第2期6卷 235-244页

作者： Yang, Keji Li, Qixin wang, fuyuan Hehai Univ Nanjing China

Based on investigation and model tests, and in combination with the research work on group effect for pile groups under lateral loads relating to the code of fixed offshore platforms, a series of studies have been performed on the behavior and failure mechanism of laterally loaded pile groups, critical pile spacing inducing group effect, lateral bearing capacity of pile groups and its main influence factors, the stress-strain relationship for single piles and pile groups and so on. Some new laws about non-uniformity of load distribution in the longitudinal direction of pile groups and load-deflection (p-y) curves for pile groups have been discovered, and an empirical formula is presented in order to remedy the defect of current calculating methods at home and abroad. These results can be used for reference in the design of pile foundation under lateral loads.

关键词： Load Distribution Marine Platforms Stresses Stresses Analysis

民宿关系营销对顾客公民行为的影响——关系质量的中介效应与动机归因的调节效应

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热带地理 2024年第4期44卷 662-672页

作者：蒋亚军蔡逸伟郭玉王甫园周慧玲桂林理工大学旅游与风景园林学院广西桂林541004 广西旅游产业研究院广西桂林541004 中国科学院地理科学与资源研究所北京100101 中国科学院区域可持续发展分析与模拟重点实验室北京100101

如何通过关系营销激发顾客公民行为,是民宿高质量发展中需要解决的科学问题。基于社会交换理论和归因理论,以关系质量(信任和互惠)为中介变量,动机归因(利己与利他)为调节变量,探索民宿关系营销(信息沟通、人情投资)对顾客公民行为的影... 详细信息

如何通过关系营销激发顾客公民行为,是民宿高质量发展中需要解决的科学问题。基于社会交换理论和归因理论,以关系质量(信任和互惠)为中介变量,动机归因(利己与利他)为调节变量,探索民宿关系营销(信息沟通、人情投资)对顾客公民行为的影响机制。通过Credamo平台收集322名民宿顾客的数据,结果表明,1)民宿情境中的顾客公民行为由帮助行为和容忍行为2个维度构成;2)民宿的关系营销对关系质量和顾客公民行为产生显著正向影响;关系质量对顾客公民行为产生显著正向影响;3)关系质量在关系营销和帮助行为的关系中具有中介效应;4)动机归因在关系营销对容忍行为的影响中发挥调节效应。研究在实践上拓宽了关系营销理论的旅游应用场景,有助于民宿维护好主客关系并激发顾客公民行为,为民宿旅游服务及产品开发提供参考。

关键词：民宿关系营销关系质量顾客公民行为动机归因

Power Allocation for SE Maximization in Uplink Massive MIMO System Under Minimum Rate Constraint

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China Communications 2024年第3期21卷 104-117页

作者： wang Hui Yu Xiangbin Liu fuyuan Bai Jiawei College of Electronic and Information Engineering Nanjing University of Aeronautics and AstronauticsNanjing 211106China Key Laboratory of Wireless Sensor Network and Communication Shanghai Institute of Microsystem and Information TechnologyChinese Academy of SciencesShanghai 200050China

In this paper,we optimize the spectrum efficiency(SE)of uplink massive multiple-input multiple-output(MIMO)system with imperfect channel state information(CSI)over Rayleigh fading channel.The SE optimization problem is formulated under the constraints of maximum power and minimum rate of each user.Then,we develop a near-optimal power allocation(PA)scheme by using the successive convex approximation(SCA)method,Lagrange multiplier method,and block coordinate descent(BCD)method,and it can obtain almost the same SE as the benchmark scheme with lower complexity.Since this scheme needs three-layer iteration,a suboptimal PA scheme is developed to further reduce the complexity,where the characteristic of massive MIMO(i.e.,numerous receive antennas)is utilized for convex reformulation,and the rate constraint is converted to linear constraints.This suboptimal scheme only needs single-layer iteration,thus has lower complexity than the near-optimal scheme.Finally,we joint design the pilot power and data power to further improve the performance,and propose an two-stage algorithm to obtain joint PA.Simulation results verify the effectiveness of the proposed schemes,and superior SE performance is achieved.

关键词： imperfect CSI massive MIMO minimum rate constraint power allocation spectral efficiency

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刚果(金)某氧化铜钴矿还原浸出试验

现代矿业 2024年第5期40卷 157-160页

作者：王福元余浔王立刚陈少学张帆周峰中国瑞林工程技术股份有限公司矿冶科技集团有限公司中钢集团马鞍山矿山研究总院股份有限公司金属矿山安全与健康国家重点实验室华唯金属矿产资源高效循环利用国家工程研究中心有限公司

刚果(金)某氧化铜钴矿铜、钴品位分别为3.93%和1.52%,矿石氧化率高,含碳酸盐脉石矿物少,磨矿解离效果好,适宜采用原矿直接酸性搅拌浸出工艺回收铜、钴。为了经济高效地回收该矿石中的铜、钴资源,从影响酸耗和浸出率多因素开展了还原浸... 详细信息

刚果(金)某氧化铜钴矿铜、钴品位分别为3.93%和1.52%,矿石氧化率高,含碳酸盐脉石矿物少,磨矿解离效果好,适宜采用原矿直接酸性搅拌浸出工艺回收铜、钴。为了经济高效地回收该矿石中的铜、钴资源,从影响酸耗和浸出率多因素开展了还原浸出试验研究。试验结果表明:在磨矿细度-0.074 mm70%、亚硫酸钠用量32 kg/t、七水硫酸亚铁用量15 kg/t、液固比3∶1、浸出时间5 h、pH值1.3~1.5的优化条件下,可获得铜浸出率97.84%、钴浸出率95.37%、脉石酸耗35.80 kg/t、总酸耗119.54 kg/t的技术经济指标,还原酸浸工艺有效地回收了该矿石中的铜、钴资源。

关键词：氧化铜钴矿孔雀石水钴矿还原浸出

Research and Experience Reference on London’s Response to Climate Change in the Twenty-first Century

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Journal of Geographical Research 2023年第1期6卷 54-68页

作者： Renrui wang fuyuan wang University College London WC1E 6BTU.K Institute of Geographic Sciences and Natural Resources Research Chinese Academy of SciencesBeijing100101China

London’s approaches to tackling climate change after the 21st century are multifaceted and relatively systematic.The aim of this research paper is to analyse London’s actions in response to climate change and to draw out what valuable lessons London has for the world in terms of its response to climate change.This paper provides an in-depth analysis of London’s policies and actions on climate mitigation in the areas of“greenhouse gas emissions”and“energy infrastructure”,and climate adaptation actions in the areas of“city green belt and urban afforestation”,“UHI and thermal crisis management”and“water supply infrastructure and sustainable drainage”.It then examines the positive aspects of these actions to determine what London has to say about climate change to the rest of the world and other cities.This paper also discovers that to effectively mitigate and adapt to climate change,London has not only established carbon reduction targets,but also created a large academic research network,represented by the LCCP.At the same time,London has developed a scientific climate change adaptation planning framework(P2R2)that focuses on four key areas:Economic,environmental,health,and infrastructure sectors,and three types of risks:Flooding,heat,and water supply,and emphasizes the dynamics and flexibility of each adaptation strategy.

关键词： Greenhouse gas reduction Urban green belts Urban heat island effect Water supply Sustainable drainage

Radar Signal Intra-Pulse Modulation Recognition Based on Deep Residual Network

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Journal of Beijing Institute of Technology 2024年第2期33卷 155-162页

作者： fuyuan Xu Guangqing Shao Jiazhan Lu Zhiyin wang Zhipeng Wu Shuhang Xia No.8511 Research Institute of China Aerospace Science&Industry Corp(CASIC) Nanjing 210007China

In view of low recognition rate of complex radar intra-pulse modulation signal type by traditional methods under low signal-to-noise ratio(SNR),the paper proposes an automatic recog-nition method of complex radar intra-pulse modulation signal type based on deep residual network.The basic principle of the recognition method is to obtain the transformation relationship between the time and frequency of complex radar intra-pulse modulation signal through short-time Fourier transform(STFT),and then design an appropriate deep residual network to extract the features of the time-frequency map and complete a variety of complex intra-pulse modulation signal type recognition.In addition,in order to improve the generalization ability of the proposed method,label smoothing and L2 regularization are introduced.The simulation results show that the proposed method has a recognition accuracy of more than 95%for complex radar intra-pulse modulation sig-nal types under low SNR(2 dB).

关键词： intra-pulse modulation low signal-to-noise deep residual network automatic recognition

Tailoring the Microstructure and Mechanical Property of Mg-Zn Matrix Composite via the Addition of Al Element

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Acta Metallurgica Sinica(English Letters) 2024年第3期37卷 438-452页

作者： Chong wang fuyuan Liu Xuejian wang Enyu Guo Zelong Du Kunkun Deng Zongning Chen Huijun Kang Guohao Du Tongmin wang Key Laboratory of Solidification Control and Digital Preparation Technology(Liaoning Province) School of Materials Science and EngineeringDalian University of TechnologyDalian 116024China School of Mechanical Engineering Guizhou UniversityGuiyang 550025China Ningbo Institute of Dalian University of Technology Ningbo 315000China Shanxi Key Laboratory of Advanced Magnesium-Based Materials College of Materials Science and EngineeringTaiyuan University of TechnologyTaiyuan 030024China Shanghai Synchrotron Radiation Facility Shanghai Advanced Research Institute CASShanghai 201204China

The semi-solid stir casting method is adopted to prepare 10 wt%SiC_(p)/Mg-6Zn-0.5Ca-xAl(x=0,1,3 and 5 wt%)composites,and the microstructure evolution and mechanical property of composites with various Al content are investigated.The results show that the addition of 3 wt%Al improves the distribution of SiC_(p),whereas the SiC_(p) cluster occurs again with Al content greater than 3%.An abnormal phenomenon of twinning is observed in the cast composites in this work.The SiC_(p)/Mg-6Zn-0.5Ca composite possesses the highest twin content of~23%,for which tension twins(TTW)and compression twins(CTW)account for~19%and~3%,respectively.The CTW is only observed in ZXA600 composite.The addition of Al has an inhibiting effect for the generation and growth of twins.The content of twin decreases firstly and then increases with increase of Al content.The lowest twin content is obtained as Al increases to 3 wt%.It is found the existence of twin is detrimental to the mechanical property of composites.As-cast SiC_(p)/Mg-6Zn-0.5Ca-3Al composite with the lowest twin content exhibits the optimal mechanical property of yield strength,ultimate tensile strength and elongation for 100 MPa,188 MPa and 4.4%,respectively.The outstanding mechanical property is attributed to the uniform distribution of SiC_(p),the low twin content and the well-distributed fine second phases.

关键词： Mg matrix composite Synchrotron tomography Twinning Liquid melt processing Mechanical property

Direct generation of Zn metal using laser-induced ZnS to eradicate carbon emissions from electrolysis Zn production

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Frontiers of Environmental Science & Engineering 2024年第1期18卷 83-95页

作者： Ying Chen Ning Duan Linhua Jiang fuyuan Xu Guangbin Zhu Yao wang Yong Liu Wen Cheng Yanli Xu State Key Laboratory of Pollution Control and Resources Reuse College of Environmental Science and EngineeringTongji UniversityShanghai 200092China Shanghai Institute of Pollution Control and Ecological Security Shanghai 200092China School of Environmental Science and Engineering Tianjin UniversityTianjin 300350China School of Materials Science and Engineering Anhui University of Science&TechnologyHuainan 232001China

In response to the goal of net-zero emissions proposed by Intergovernmental Panel on Climate Change, Chinese government has pledged that carbon emissions will peak by 2030, and achieve carbon neutrality by 2060. However, the high carbon energy structure of traditional industries has aggravated environmental problems, such as greenhouse effect and air pollution. The goal of carbon neutrality will be difficult to achieve without the development of disruptive theories and technologies. The electrolytic zinc industry requires high-temperature roasting at ~1000 ℃, generating large amounts of greenhouse gases and SO_(2). High concentrations of sulfuric acid (200 g/L) are subsequently used for electrolysis, and each ton of zinc produced generates 50 kg of anode slime with lead content of up to 16%, as well as 0.35 m3 of wastewater containing zinc and lead. To solve these problems, an optical metallurgy method is proposed in this study. The proposed method uses laser-induced photoreduction to decompose ZnS and reduce metal ions to metal. Results indicate that Zn0 and S8 can be detected on the surface of ZnS at a specific wavelength and laser fluence. The generation mechanism of Zn0 is such that laser induces an electronic transition that breaks ionic bond in ZnS, resulting in its decomposition and photoreduction to Zn0 under an inert argon gas atmosphere. This method does not reduce other metals in the mineral since it does not use high-temperature roasting, providing a new way of producing high-purity metal without greenhouse gas emissions and heavy metal pollution caused by traditional zinc electrolysis.

关键词： Laser metallurgy ZnS Photochemical reduction Zinc