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Petroleum 2024年第3期10卷 548-556页

作者： Liping Tang Jiaxin Zou kenan Song Yongheng Shi Li Liu School of Mechatronic Engineering Southwest Petroleum UniversityChengdu610500China School of Engineering University of AberdeenAberdeenAB243UEUK Oil&Gas Control Center National Petroleum and Natural Gas Pipeline Network Group Co.Ltd.Beijing100020China

Marine unbonded flexible pipes serve as the most essential equipment in offshore oil and gas exploration and *** compressive loads during installation or in service in the complex marine environment usually lead to buckling failure.A flexible pipe is a composite structure with multiple functional layers,of which the tensile armor layer plays a key role with regard to the response of the pipe subjected to axial *** this paper,a simplified three-dimensional finite element model is developed,focusing on the tensile layer and replacing the carcass layer,pressure sheath layer,and pressure armor layer by a cylindrical rigid body to reduce computational *** using this model,the buckling failure modes of the tensile armor layer(in particular the birdcaging phenomenon)are *** key parameters that affect the stability of the flexible pipe under axial compression and torsion are emphasized,and their effects on its axial and torsional stiffness are compared and *** results show that both the lay angle of the steel wires and the interlayer friction coefficient have a significant influence on the axial and torsional stiffness of the pipe,whereas the damaged length of the outer sheath has virtually no effect.

关键词： Flexible pipe Tensile armor Buckling failure Key parameters Stiffness

Dynamic Forecasting of Traffic Event Duration in Istanbul:A Classification Approach with Real-Time Data Integration

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Computers, Materials & Continua 2024年第8期80卷 2259-2281页

作者： Mesut Ulu Yusuf Sait Türkan kenan Menguc Ersin Namlı Tarık Kucukdeniz Occupational Health and Safety Department Bandirma Onyedi Eylul UniversityBalikesir10200Türkiye Department of Industrial Engineering Istanbul University-CerrahpasaIstanbul34320Türkiye Department of Industrial Engineering Istanbul Technical UniversityIstanbul34467Türkiye

Today,urban traffic,growing populations,and dense transportation networks are contributing to an increase in traffic *** incidents include traffic accidents,vehicle breakdowns,fires,and traffic disputes,resulting in long waiting times,high carbon emissions,and other undesirable *** is vital to estimate incident response times quickly and accurately after traffic incidents occur for the success of incident-related planning and response *** study presents a model for forecasting the traffic incident duration of traffic events with high *** proposed model goes through a 4-stage process using various features to predict the duration of four different traffic events and presents a feature reduction approach to enable real-time data collection and *** the first stage,the dataset consisting of 24,431 data points and 75 variables is prepared by data collection,merging,missing data processing and data *** the second stage,models such as Decision Trees(DT),K-Nearest Neighbour(KNN),Random Forest(RF)and Support Vector Machines(SVM)are used and hyperparameter optimisation is performed with *** the third stage,feature selection and reduction are performed and real-time data are *** the last stage,model performance with 14 variables is evaluated with metrics such as accuracy,precision,recall,F1-score,MCC,confusion matrix and *** RF model outperforms other models with an accuracy of 98.5%.The study’s prediction results demonstrate that the proposed dynamic prediction model can achieve a high level of success.

关键词： Traffic event duration forecasting machine learning feature reduction shapley additive explanations(SHAP)

Integrated Stratigraphy and Mineralogy of the Doushantuo Formation in Weng’an,South China,and Implications for Ediacaran Phosphogenesis

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Journal of Earth Science 2024年第2期35卷 476-503页

作者： Liangxuan Jiao Zhenbing She Dominic Papineau Yaguan Zhang Matthew S.Dodd kenan Cao Qun Chen Guoyong Chen State Key Laboratory of Biogeology and Environmental Geology China University of GeosciencesWuhan430078China School of Earth Sciences China University of GeosciencesWuhan430047China London Centre for Nanotechnology University College London17-19 Gordon StreetLondonWC1E 6BTUK Department of Earth Sciences University College LondonLondonWC1E 6BTUK Centre for Planetary Science University College London and Birkbeck CollegeLondonWC1E 7HXUK Innovation Center of Ore Resources Exploration Technology in the Region of Bedrock Ministry of Natural Resources of People’s Republic of China’Guiyang550000China Guizhou Bureau of Geology and Mineral Exploration and Development Guiyang550000China

The Ediacaran–Cambrian Phosphogenic Episode is the Earth’s first true phosphogenic event and resulted in worldwide phosphate deposits,which occurred during the processes of the Neoproterozoic Oxygenation *** Ediacaran Doushantuo Formation(ca.635–551 Ma)of Weng’an area in central Guizhou,South China,contains two economic phosphorite beds(the Lower and Upper Phosphorite Beds).This paper presents a detailed stratigraphic,sedimentological and mineralogical study of multiple outcrop and drill core sections of the Doushantuo Formation across the Weng’an area,and identified 11 lithofacies and 4 types of phosphatic *** differences in lithofacies and grain types between the upper and lower phosphate deposits are observed,indicating that the two sets of phosphate deposits are the products of two distinct phosphogenic *** Lower Phosphorite Bed mainly consists of banded and laminated phosphorites,contains micro-oncoids formed by microbially-mediated precipitation and peloids formed by in-situ chemically oscillating reactions,indicating a biochemical and chemical enrichment of phosphorus to sediments during the Early Ediacaran *** Upper Phosphorite Bed is mainly composed of carbonaceous,massive,and stromatolitic phosphorites,contains bioclasts(phosphatized spheroidal fossils),and intraclasts formed by hydrodynamic agitation,suggesting that the major accesses of phosphorus to sediments were the remineralization of organic *** of the two economic phosphorite beds was controlled by two sea-level *** differences have also been documented in contemporaneous phosphate-bearing successions in Brazil and Mangolia,indicating a significant shift in global phosphogenic mechanism during the early and middle Ediacaran,which may be due to the changes in redox conditions in seawater,associated with the Neoproterozoic Oxygenation *** regional active P-cycle processes could produce more free oxygen,which may have contributed to the up

关键词： phosphorite lithofacies phosphatic grains phosphogenic paragenesis phosphorus cycle mineralogy

Operation and Management of Electrical Equipment in Iron and Steel Enterprises

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Frontiers of Metallurgical Industry

Frontiers of Metallurgical Industry 2024年第1期2卷 5-8页

作者： Wen Liao kenan Yang College of Metallurgy and Materials Engineering Chongqing University of Science and Technology

How to ensure the reliable operation of the complex and huge electrical system composed of a large number of electrical equipment in iron and steel enterprises?Combined with working experience,the author introduces four main factors affecting the normal operation of equipment,analyzes five main problems existing in the operation and management of electrical equipment,and puts forward corresponding improvement measures,so as to improve the management level of electrical equipment in iron and steel enterprises.

关键词： iron and steel enterprises electrical equipment operation management

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碲对硫化物轧制变形行为影响的研究

钢铁钒钛 2021年第3期42卷 180-186页

作者：沈平王冬张浩杨乾坤艾克南曾志崎付建勋上海大学材料科学与工程学院先进凝固技术中心省部共建高品质特殊钢冶金与制备国家重点实验室上海200444 鞍钢股份有限公司辽宁鞍山114000

采用扫描电镜对38MnVS6钢中Te的赋存状态进行了分析,采用Gleeble-3500模拟了轧制过程。对MnS夹杂和基体的硬度进行了检测,并对夹杂物进行了统计,由此对夹杂物的变形行为进行研究。结果表明,少量的Te首先固溶在MnS中,当Te含量超过130×10... 详细信息

采用扫描电镜对38MnVS6钢中Te的赋存状态进行了分析,采用Gleeble-3500模拟了轧制过程。对MnS夹杂和基体的硬度进行了检测,并对夹杂物进行了统计,由此对夹杂物的变形行为进行研究。结果表明,少量的Te首先固溶在MnS中,当Te含量超过130×10^(-6)时开始析出MnTe。经过热压缩后,随着Te含量的增加,夹杂物的长宽比从2.3逐渐降低至1.8左右。钢中Te含量增加,夹杂物与钢基体的硬度比H_(夹)/H_(钢)基本为一个常数,不能造成夹杂物的抗变形能力增加。经过热压缩后,较小的夹杂物其长宽比也较小。钢中加Te后可使夹杂物尺寸减小,进而减小了夹杂物的变形量,抑制了轧制过程中夹杂物的变形。

关键词： 38MnVS6 Te MnS夹杂 Gleeble

基于事件触发队形优化的多四旋翼无人机协同吊挂运输系统控制

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工程科学学报 2024年第9期46卷 1535-1543页

作者：花翔宇陈谋雍可南刘伟南京航空航天大学自动化学院南京210016

无人机吊挂运输系统控制是近年无人机飞行控制方法与工程应用的热点研究之一.本文提出了一种基于事件触发队形优化的多四旋翼吊挂运输系统控制方法,在实现负载运输的同时,通过动态调整无人机集群队形降低无人机功耗.根据负载的期望受力... 详细信息

无人机吊挂运输系统控制是近年无人机飞行控制方法与工程应用的热点研究之一.本文提出了一种基于事件触发队形优化的多四旋翼吊挂运输系统控制方法,在实现负载运输的同时,通过动态调整无人机集群队形降低无人机功耗.根据负载的期望受力,通过构建优化算法滚动求解四旋翼集群当前时刻下的最优队形,并利用事件触发机制降低优化问题求解计算量.进而,采用反步法设计协同飞行控制律,并通过李雅普诺夫方法证明了闭环系统的稳定性,以及有限时间内事件触发次数的有界性.最后,通过数值仿真验证了所提出控制方法的有效性.

关键词：协同吊挂运输系统队形优化事件触发四旋翼飞行控制

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我国竞技体育财政支持效率及影响因素分析

北京体育大学学报 2024年第2期47卷 10-24页

作者：韩松周克男刘思语中国人民大学经济学院运筹学与数量经济研究所北京100872 中国人民大学经济学院北京100872

研究财政对竞技体育的支持效率和影响因素分析,对提高我国竞技体育水平,建设现代化体育强国具有重要意义。构建了两阶段网络DEA模型,将我国竞技体育财政支持系统细化为体育财政阶段和竞技体育绩效阶段,通过2016—2019年数据计算整体及... 详细信息

研究财政对竞技体育的支持效率和影响因素分析,对提高我国竞技体育水平,建设现代化体育强国具有重要意义。构建了两阶段网络DEA模型,将我国竞技体育财政支持系统细化为体育财政阶段和竞技体育绩效阶段,通过2016—2019年数据计算整体及子阶段效率,并结合随机效应模型对我国竞技体育效率进行影响因素分析。研究表明,我国各省竞技体育财政支持系统效率处于波浪式变化趋势,且体育财政阶段效率明显高于竞技体育绩效阶段;从动态演进的角度来看,各省份财政支持系统间的效率差距在缩小,但竞技体育绩效阶段出现两极分化现象,且效率较低的省份出现效率值进一步降低的趋势。此外,我国东北地区的竞技体育绩效阶段效率值高于其他地区,并且优势明显,西部地区效率水平最低。进一步研究发现,加强体育交流与合作会提升我国高水平竞技体育的表现,且西部地区提升幅度最大;高质量的人才水平及科技创新对竞技体育的发展具有正向影响,其中人才水平的影响最为显著,反映了全社会劳动力水平对竞技体育绩效阶段效率的重要作用。

关键词：竞技体育财政支持系统两阶段网络DEA模型随机效应模型交流与合作劳动力水平

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都是“乡”建——于在地建造网络中

建筑技艺（中英文） 2024年第3期30卷 6-15页

作者：刘可南上海旭可建筑设计有限公司

以存在于工业体系性建造和民间在地建造的交锋面的“在地建造网络”为线索,回溯旭可建筑在三组具体建造过程中的思考与操作。作为在地建造网络中有作者身份的行动者或协调者,建筑师能够通过调配在地资源的组合关系、寻找在地建造网络同... 详细信息

以存在于工业体系性建造和民间在地建造的交锋面的“在地建造网络”为线索,回溯旭可建筑在三组具体建造过程中的思考与操作。作为在地建造网络中有作者身份的行动者或协调者,建筑师能够通过调配在地资源的组合关系、寻找在地建造网络同盟等方式,回应当代复杂的城乡建造现实。

关键词：乡建在地建造网络回收修补地域主义半工业化

基于融合改进K-means聚类算法的数据检测技术

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电子设计工程 2024年第5期32卷 41-45页

作者：郭克难河北北方学院附属第一医院河北张家口075000

针对现有医疗财务数据分析系统平台老旧,采用传统K-means算法进行数据处理时性能较差的问题,文中设计了一种财务异常数据检测算法。对于传统K-means算法存在的分类效果不佳、运行效率偏低等不足,该算法结合密度峰值法对样本点的局部密... 详细信息

针对现有医疗财务数据分析系统平台老旧,采用传统K-means算法进行数据处理时性能较差的问题,文中设计了一种财务异常数据检测算法。对于传统K-means算法存在的分类效果不佳、运行效率偏低等不足,该算法结合密度峰值法对样本点的局部密度和高密度距离进行计算,进而优化簇中心的选择。同时融合PCA降维算法减少了数据的冗余信息,进一步提高了运行效率。通过引入LOF离群检测算法对分簇后的数据进行检测,从而得到异常数据结果。实验测试中,所提算法在人工数据集上的平均ARI指标为0.844,真实数据集的准确率则达到了79.2%,在所有对比算法中均为最优,表明该算法具有良好的性能,可以对财务异常数据进行准确地检测。

关键词： K-means聚类密度峰值检测主成分分析法离群检测算法异常数据检测