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A comprehensive comparison of different regression techniques and nature-inspired optimization algorithms to predict carbonation depth of recycled aggregate concrete

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Frontiers of Structural and Civil Engineering 2024年第1期18卷 30-50页

作者： bin XI ning ZHANG Enming LI Jiabin LI Jian ZHOU Pablo SEGARRA Department of Civil and Environmental Engineering Politecnico Di MilanoMilano 20133Italy Leibniz Institute of Ecological Urban and Regional Development(IOER) Dresden 01217Germany Universidad Politécnica de Madrid-ETSI Minas y Energía Madrid 28003Spain Department of Civil Engineering KU Leuven CampusBrugge 8200Belgium School of Resources and Safety Engineering Central South UniversityChangsha 410083China

The utilization of recycled aggregates(RA)for concrete production has the potential to offer substantial environmental and economic advantages.However,RA concrete is plagued with considerable durability concerns,particularly carbonation.To advance the application of RA concrete,the establishment of a reliable model for predicting the carbonation is needed.On the one hand,concrete carbonation is a long and slow process and thus consumes a lot of time and energy to monitor.On the other hand,carbonation is influenced by many factors and is hard to predict.Regarding this,this paper proposes the use of machine learning techniques to establish accurate prediction models for the carbonation depth(CD)of RA concrete.Three types of regression techniques and meta-heuristic algorithms were employed to provide more alternative predictive tools.It was found that the best prediction performance was obtained from extreme gradient boosting-multi-universe optimizer(XGB-MVO)with R^(2) value of 0.9949 and 0.9398 for training and testing sets,respectively.XGB-MVO was used for evaluating physical laws of carbonation and it was found that the developed XGB-MVO model could provide reasonable predictions when new data were investigated.It also showed better generalization capabilities when compared with different models in the literature.Overall,this paper emphasizes the need for sustainable solutions in the construction industry to reduce its environmental impact and contribute to sustainable and low-carbon economies.

关键词： recycled aggregate concrete carbonation depth nature-inspired optimization algorithms extreme gradient boosting technique parametric analysis

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Impacts of major volcanic eruptions over the past two millennia on both global and Chinese climates:A review

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Science China Earth Sciences 2024年第1期67卷 61-78页

作者： Weiyi SUN Deliang CHEN Guonian LÜ Liang ning Chaochao GAO Renhe ZHANG bin WANG Jian LIU Key Laboratory for Virtual Geographic Environment Ministry of EducationState Key Laboratory Cultivation Base of Geographical Environment Evolution of Jiangsu ProvinceJiangsu Center for Collaborative Innovation in Geographical Information Resource Development and ApplicationSchool of Geography ScienceNanjing Normal UniversityNanjing 210023China Regional Climate Group Department of Earth SciencesUniversity of GothenburgGothenburg 40530Sweden College of Environmental and Resource Science Zhejiang UniversityHangzhou 310058China Department of Atmospheric and Oceanic Sciences&Institute of Atmospheric Sciences Fudan UniversityShanghai 200437China Department of Atmospheric Sciences and Atmosphere-Ocean Research Center University of Hawaii at ManoaHonoluluHI 96825USA Jiangsu Provincial Key Laboratory for Numerical Simulation of Large Scale Complex Systems School of Mathematical ScienceNanjing Normal UniversityNanjing 210023China Open Studio for the Simulation of Ocean-Climate-Isotope Qingdao National Laboratory for Marine Science and TechnologyQingdao 266237China

Major volcanic eruptions(MVEs)have attracted increasing attention from the scientific community.Previous studies have explored the climatic impact of MVEs over the past two millennia.However,proxy-based reconstructions and climate model simulations indicate divergent responses of global and China’s regional climates to MVEs.Here,we used multiple data from observations,reconstructions,simulations,and assimilations to summarize the historical facts of MVEs,the characteristics and mechanisms of their climatic impact,and directions for future research.We reviewed volcanic datasets and determined intensive MVE periods;these periods corresponded to the years 530–700,1200‒1460,and 1600‒1840 CE.After tropical MVEs,a substantial cooling effect is observed throughout the globe and China on the interannual-interdecadal time scales but an inconsistent cooling magnitude is detected between reconstructions and simulations.In the first summer after tropical MVEs,a decrease in global and monsoonal precipitation is observed.In reconstructions and simulations,an increased precipitation is seen for the Yangtze River Basin,while large uncertainties in precipitation changes are present for other regions of China.Decadal drought can be induced by frequent eruptions and volcanism superimposed on low solar irradiation and internal variability.MVEs affect climate directly through the radiative effect and indirectly by modulating internal variability,such as the El Niño‒Southern Oscillation(ENSO)and Atlantic Multidecadal Oscillation(AMO).However,changes in the phase,amplitude,and periodicity of ENSO and AMO after MVEs and the associated mechanisms remain controversial,which could account for model-reconstruction disagreements.Moreover,other internal variability,uncertainties in reconstruction methods and aerosol‒climate models,and climate background may also induce model-reconstruction disagreements.Knowledge gaps and directions for future research are also discussed.

关键词： Major volcanic eruption Climate variability Mechanism Past two millennia Internal variability

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Aerodynamic Features of High-Speed Maglev Trains with Different Marshaling Lengths Running on a Viaduct under Crosswinds

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Computer Modeling in Engineering & Sciences 2024年第7期140卷 975-996页

作者： Zun-Di Huang Zhen-bin Zhou ning Chang Zheng-Wei Chen Su-Mei Wang School of Rail Transportation Wuyi UniversityJiangmen529020China National Rail Transit Electrification and Automation Engineering Technology Research Center(Hong Kong Branch) The Hong Kong Polytechnic UniversityHong Kong999077China Department of Civil and Environmental Engineering The Hong Kong Polytechnic UniversityHong Kong999077China

The safety and stability of high-speed maglev trains traveling on viaducts in crosswinds critically depend on their aerodynamic characteristics.Therefore,this paper uses an improved delayed detached eddy simulation(IDDES)method to investigate the aerodynamic features of high-speed maglev trains with different marshaling lengths under crosswinds.The effects of marshaling lengths(varying from 3-car to 8-car groups)on the train’s aerodynamic performance,surface pressure,and the flow field surrounding the train were investigated using the three-dimensional unsteady compressible Navier-Stokes(N-S)equations.The results showed that the marshaling lengths had minimal influence on the aerodynamic performance of the head and middle cars.Conversely,the marshaling lengths are negatively correlated with the time-average side force coefficient(CS)and time-average lift force coefficient(Cl)of the tail car.Compared to the tail car of the 3-car groups,the CS and Cl fell by 27.77%and 18.29%,respectively,for the tail car of the 8-car groups.It is essential to pay more attention to the operational safety of the head car,as it exhibits the highest time average CS.Additionally,the mean pressure difference between the two sides of the tail car body increased with the marshaling lengths,and the side force direction on the tail car was opposite to that of the head and middle cars.Furthermore,the turbulent kinetic energy of the wake structure on the windward side quickly decreased as marshaling lengths increased.

关键词： High-speed maglev train marshaling lengths crosswinds aerodynamic features

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{1012}twin–twin intersection-induced lattice rotation and dynamic recrystallization in Mg–6Al–3Sn–2Zn alloy

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Journal of Magnesium and Alloys 2024年第4期12卷 1529-1539页

作者： bin-Jiang Lv Sen Wang Fu-Hao Gao ning Cui Yi-Nan Li Tie-Wei Xu Feng Guo School of Mechanical and Automotive Engineering Qingdao University of Technology266520China Key Lab of industrial Fluid Energy Conservation and Pollution Control Qingdao University of Technology266520China

This study investigated the formation mechanism of new grains due to twin–twin intersections in a coarse-grained Mg–6Al–3Sn–2Zn alloy during different strain rates of an isothermal compression.The results of electron backscattered diffraction investigations showed that the activated twins were primarily{1012}tension twins,and 60°boundaries formed due to twin–twin intersections under different strain rates.Isolated twin variants with 60°boundaries transformed into new grains through lattice rotations at a low strain rate(0.01 s^(−1)).At a high strain rate(10 s^(−1)),the regions surrounded by subgrain boundaries through high-density dislocation arrangement and the 60°boundaries transformed into new grains via dynamic recrystallization.

关键词： Mg alloy Twin-twin intersection Lattice rotation Dynamic recrystallization

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Scavenging and release of REE and HFSE by Na-metasomatism in magmatic-hydrothermal systems

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Fundamental Research 2024年第2期4卷 315-323页

作者： Wu-bin Yang He-Cai Niu ning-Bo Li Pete Hollings Shannon Zurevinski Roger H.Mitchell Key Laboratory of Mineralogy and Metallogeny/Guangdong Provincial Key Laboratory of Mineral Physics and Materials Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China CAS Center for Excellence in Deep Earth Science Guangzhou 510640China Department of Geology Lakehead UniversityThunder BayON P7B 5E1Canada

Exploitable or potentially exploitable deposits of critical metals,such as rare-earth(REE)and high-field-strength elements(HFSE),are commonly associated with alkaline or peralkaline igneous rocks.However,the origin,transport and concentration of these metals in peralkaline systems remains poorly understood.This study presents the results of a mineralogical and geochemical investigation of the Na-metasomatism of alkali amphiboles and clinopyroxenes from a barren peralkaline granite pluton in NE China,to assess the remobilization and redistribution of REE and HFSE during magmatic-hydrothermal evolution.Alkali amphiboles and aegirine-augites from the peralkaline granites show evolutionary trends from sodic-calcic to sodic compositions,with increasing REE and HFSE concentrations as a function of increasing Na-index[Na^(#),defined as molar Na/(Na+Ca)ratios].The Na-amphiboles(i.e.,arfvedsonite)and aegirine-augites can be subsequently altered,or breakdown,to form hydrothermal aegirine during late-or post-magmatic alteration.Representative compositions analyzed by insitu LA-ICPMS show that the primary aegirine-augites have high and variable REE(2194-3627 ppm)and HFSE(4194-16,862 ppm)contents,suggesting that these critical metals can be scavenged by alkali amphiboles and aegirine-augites.Compared to the primary aegirine-augites,the presentative early replacement aegirine(Aeg-I,Na^(#)=0.91-0.94)has notably lower REE(1484-1972)and HFSE(4351-5621)contents.In contrast,the late hydrothermal aegirine(Aeg-II,Na^(#)=0.92-0.96)has significantly lower REE(317-456 ppm)and HFSE(6.44-72.2 ppm)contents.Given that the increasing Na^(#)from aegirine-augites to hydrothermal aegirines likely resulted from Na-metasomatism,a scavenging-release model can explain the remobilization of REE and HFSE in peralkaline granitic systems.The scavenging and release of REE and HFSE by Na-metasomatism provides key insights into the genesis of globally significant REE and HFSE deposits.The high Na-index of the hydrothermal aegirine might be useful as a geo

关键词： Critical metals Alkali amphiboles Na-metasomatism REE and HFSE Na-index(Na^(#))

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Down-regulating Circular RNA Prkcsh suppresses the inflammatory response after spinal cord injury

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Neural Regeneration Research 2022年第1期17卷 144-151页

作者： Jia-Nan Chen Yi-ning Zhang Li-Ge Tian Ying Zhang Xin-Yu Li bin ning Department of Orthopedics Jinan Central HospitalCheeloo College of MedicineShandong UniversityJinanShandong ProvinceChina Department of Orthopedics Central Hospital Affiliated to Shandong First Medical UniversityJinanShandong ProvinceChina

Circular RNAs(circRNAs)are a class of conserved,endogenous non-coding RNAs that are involved in transcriptional and post-transcriptional gene regulation and are highly enriched in the nervous system.They participate in the survival and differentiation of multiple nerve cells,and may even promote the recovery of neurological function after stroke.However,their role in the inflammatory response after spinal cord injury remains unclear.In the present study,we established a mouse model of T9 spinal cord injury using the modified Allen’s impact method,and identified 16,013 circRNAs and 960 miRNAs that were differentially expressed after spinal cord injury.Of these,the expression levels of circPrkcsh were significantly different between injured and sham-treated mice.We then treated astrocytes with tumor necrosis factor-αin vitro to simulate the inflammatory response after spinal cord injury.Our results revealed an elevated expression of circPrkcsh with a concurrent decrease in miR-488 expression in injured cells.We also found that circPrkcsh regulated the expression of the inflammationrelated gene Ccl2.Furthermore,in tumor necrosis factor-α-treated astrocytes,circPrkcsh knockdown decreased the expression of Ccl2 by upregulating miR-488 expression,and reduced the secretion of inflammatory cytokines in vitro.These findings suggest that differentially expressed circRNAs participate in the inflammatory response after spinal cord injury and act as the regulators of certain microRNAs.Furthermore,circPrkcsh may be used as an miR-488 sponge to regulate Ccl2 expression,which might provide a new potential therapy for SCI.The study was approved by the Animal Ethics Committee of Shandong University of China(approval No.KYLL-20170303)on March 3,2017.

关键词： astrocyte Ccl2 ceRNA circRNA inflammation miR-488 ncRNA Prkcsh RNA sequencing spinal cord injury

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基于模型预测控制与改进人工势场法的多无人机路径规划

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控制与决策 2024年第7期39卷 2133-2141页

作者：鲜斌宋宁天津大学电气自动化与信息工程学院

模型预测控制(model predictive control, MPC)已成功地应用于无人机集群的路径规划.但其存在计算量大及单步运算时间长等不足,在实时运行中往往难以获得较高的控制频率.而离线的MPC需要准确的地图信息,难以处理地图中无法预测的动态障... 详细信息

模型预测控制(model predictive control, MPC)已成功地应用于无人机集群的路径规划.但其存在计算量大及单步运算时间长等不足,在实时运行中往往难以获得较高的控制频率.而离线的MPC需要准确的地图信息,难以处理地图中无法预测的动态障碍物.对此,提出一种结合离线MPC全局规划与在线改进人工势场法局部规划的方法.在利用MPC方法生成安全、平滑轨迹的同时,提高无人机在动态障碍物影响下的避障能力.通过引入调节力来处理传统人工势场法的局部极小值问题,并将目标与无人机的相对距离引入斥力函数,同时改进引力函数,以改善无人机在目标点处低速徘徊的问题.此外,设计一种事件触发的无人机轨迹变更与轨迹恢复策略,使无人机仅在必要时实施动态避障行为.在此基础上,最大化利用原来的规划轨迹.仿真验证结果表明,所提出的路径规划方法能够使无人机集群安全飞行至目标点,并且具有良好的动态避障能力.

关键词：多无人机模型预测控制人工势场路径规划动态障碍物事件触发

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A Review of Intelligent Configuration and Its Security for Complex Networks

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Chinese Journal of Electronics 2024年第4期33卷 920-947页

作者： Yue ZHAO bin YANG Fei TENG Xianhua NIU ning HU Bo TIAN Science and Technology on Communication Security Laboratory School of Computer and Information Engineering Chuzhou University School of Computing and Artificial Intelligence Southwest Jiaotong University School of Computer and Software Engineering Xihua University Cyberspace Institute of Advanced Technology Guangzhou University

Complex networks are becoming more complex because of the use of many components with diverse technologies. In fact, manual configuration that makes each component interoperable has breed latent danger to system security. There is still no comprehensive review of these studies and prospects for further research. According to the complexity of component configuration and difficulty of security assurance in typical complex networks, this paper systematically reviews the abstract models and formal analysis methods required for intelligent configuration of complex networks, specifically analyzes, and compares the current key technologies such as configuration semantic awareness, automatic generation of security configuration, dynamic deployment, and verification evaluation. These technologies can effectively improve the security of complex networks intelligent configuration and reduce the complexity of operation and maintenance. This paper also summarizes the mainstream construction methods of complex networks configuration and its security test environment and detection index system, which lays a theoretical foundation for the formation of the comprehensive effectiveness verification capability of configuration security. The whole lifecycle management system of configuration security process proposed in this paper provides an important technical reference for reducing the complexity of network operation and maintenance and improving network security.

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circRNAs deregulation in exosomes derived from BEAS-2B cells is associated with vascular stiffness induced by PM_(2.5)

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Journal of Environmental Sciences 2024年第3期137卷 527-539页

作者： Qingping Liu Yaling Zhang bin Han Mengruo Wang Huaifang Hu Jie ning Wentao Hu Meiyu Chen Yaxian Pang Yuanyuan Chen Lei Bao Yujie Niu Rong Zhang Department of Toxicology Hebei Medical UniversityShijiazhuang 050017China State Key Laboratory of Environment Health(Incubation) Key Laboratory of Environment and HealthMinistry of EducationKey Laboratory of Environment and Health(Wuhan)Ministry of Environmental ProtectionSchool of Public HealthTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China China CDC Key Laboratory of Environment and Population Health National Institute of Environmental HealthChinese Center for Disease Control and PreventionBeijing 100021China Occupational Health and Environmental Health Hebei Medical UniversityShijiazhuang 050017China Hebei Key Laboratory of Environment and Human Health Hebei Medical UniversityShijiazhuang 050017China

As an environmental pollutant,ambient fine particulate matter (PM_(2.5)) was linked to cardiovascular diseases.The molecular mechanisms underlying PM_(2.5)-induced extrapulmonary disease has not been elucidated clearly.In this study the ambient PM_(2.5)exposure mice model we established was to explore adverse effects of vessel and potential mechanisms.Long-term PM_(2.5)exposure caused reduced lung function and vascular stiffness in mice.And chronic PM_(2.5)induced migration and epithelial-mesenchymal transition (EMT) phenotype in BEAS-2B cells.After PM_(2.5)treatment,the circRNAs and mRNAs levels of exosomes released by BEAS-2B cells were detected by competing endogenous RNA (ceRNA) array,which contained 1664 differentially expressed circRNAs (DE-circRNAs) and 308 differentially expressed m RNAs (DE-mRNAs).By bioinformatics analysis on host genes of DE-circRNAs,vascular diseases and some pathways related to vascular diseases including focal adhesion,tight junction and adherens junction were enriched.Then,ceRNA network was constructed,and DE-mRNAs in ceRNA network were conducted functional enrichment analysis by Ingenuity Pathway Analysis,which indicated that hsa_circ_0012627,hsa_circ_0053261and hsa_circ_0052810 were related to vascular endothelial dysfunction.Furthermore,it was verified experimentally that Exo^(PM2.5)could induce endothelial dysfunction by increased endothelial permeability and decreased relaxation in vitro.In present study,we investigated in-depth knowledge into the molecule events related to PM_(2.5) toxicity and pathogenesis of vascular diseases.

关键词： Fine particulate matter Vascular stiffness Exosome ceRNA microarray Endothelial dysfunction

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Distal-scanning common path probe for optical coherence tomography

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Journal of Innovative Optical Health Sciences 2024年第3期17卷 84-92页

作者： Zhengyu Chen bin He Zichen Yin Zhangwei Hu Yejiong Shi Chengming Wang Xiao Zhang ning Zhang Linkai Jing Guihuai Wang Ping Xue State Key Laboratory of Low-dimensional Quantum Physics and Department of Physics Tsinghua UniversityBeijingChina Frontier Science Center for Quantum Information BeijingChina Jinsp Company Limited BeijingChina Beijing Institute of Technology BeijingChina Institute of Forensic Science Ministry of Public Security BeijingChina Department of Neurosurgery Beijing Tsinghua Changgung HospitalSchool of Clinical Medicine and Institute of Precision MedicineTsinghua UniversityBeijingChina

In this paper,we present a distal-scanning common path probe for optical coherence tomography(OCT)equipped with a hollow ultrasonic motor and a simple and specially designed beam-splitter.This novel probe proves to be able to effectively circumvent polarization and dispersion mismatch caused by fiber motion and is more robust to a variety of interfering factors during the imaging process,experimentally compared to a conventional noncommon path probe.Furthermore,our design counteracts the attenuation of backscattering with depth and the fall-off of the signal,resulting in a more balanced signal range and greater imaging depth.Spectral-domain OCT imaging of phantom and biological tissue is also demonstrated with a sensitivity of∼100dB and a lateral resolution of∼3μm.This low-cost probe offers simplified system configuration and excellent robustness,and is therefore particularly suitable for clinical diagnosis as one-off medical apparatus.

关键词： Common path optical coherence tomography endoscopic probe

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