检索结果-南通市图书馆

Influence of the Spudcan Angle on the Ultimate Bearing Capacity of Jack-up Platform

在线全文

学校读者我要写书评

暂无评论

China Ocean Engineering 2018年第4期32卷 476-481页

作者： ZHANG Qi-yi liu zhi-jie Department of Ocean Engineering College of EngineeringOcean University of ChinaQingdao 266100China Key Laboratory of Ocean Engineering of Shandong Province Qingdao 266100China

Jack-up platforms of the Ocean engineering structures always withstand the vertical gravity loads which are applied to the seabed by spudcan, so it is important to determine the bearing capacity and the penetration depth of the spudcan for its geometry. In fact, it is up to the deformation law and the failure modes of soil surrounding the spudcan which can calculate the ultimate bearing capacity of the spudcan foundation on the soil seabed. By using the finite element analysis software Abaqus, the deformation law of soil around the spudcan is analyzed in detail, and the failure modes of soil surrounding the spudcan foundation are achieved. At the same time, based on the limit equilibrium theory, by use of static permissible slip-line field, the ultimate bearing capacity of the spudcan foundation is analyzed and the lower limit solution is derived theoretically, and the effect of the spudcan angle on the ultimate bearing capacity is investigated. The numerical results are compared with those obtained by the theoretical formulas deduced in this paper. On the basis of the lower limit solutions in this paper, the effect of the spudcan angle on the ultimate bearing capacity is revealed, and a practical bearing capacity formula is given to take the effect of the spudcan angle into consideration.

关键词： spudcan lower limit analysis ultimate bearing capacity failure modes Abaqus

在线全文

学校读者我要写书评

暂无评论

郁闭果园图传遥控式割草机的设计与性能试验

吉林大学学报（工学版） 2024年第1期54卷 281-293页

作者：杨福增孙景彬李亚男张亚洲刘志杰西北农林科技大学机械与电子工程学院陕西杨凌712100 农业农村部苹果全程机械化科研基地陕西杨凌712100 农业农村部北方农业装备科学观测实验站陕西杨凌712100

针对传统郁闭果园内部空间狭窄密闭,现有割草机难以进入作业,面临无机可用的生产难题,设计了一种适用于郁闭果园环境、割茬高度可调且株间避障灵活便捷的小型图传遥控式割草机。在分析郁闭果园种植模式和割草农艺要求的基础上,确定了割... 详细信息

针对传统郁闭果园内部空间狭窄密闭,现有割草机难以进入作业,面临无机可用的生产难题,设计了一种适用于郁闭果园环境、割茬高度可调且株间避障灵活便捷的小型图传遥控式割草机。在分析郁闭果园种植模式和割草农艺要求的基础上,确定了割草机的总体设计方案,然后对割草机关键部件(刀盘高度调节机构、株间避障切割机构、遥控及图传系统等)进行了设计与匹配选型,最后完成了整机集成与性能试验。基本性能试验结果表明:割草机整机尺寸(长×宽×高)为1.9 m×1.7 m×0.7 m,割茬高度调节范围为30~110 mm,株间避障通过率为100%,遥控和图传距离均大于110 m。同时以前进速度、刀盘转速和割茬高度为试验因素,割茬稳定系数、割幅利用率和漏割率为试验性能指标开展正交试验,并对试验结果进行显著性分析。结果表明,各因素对割茬稳定系数、割幅利用率和漏割率性能指标影响的主次顺序均为前进速度、刀盘转速和割茬高度;确定的较优方案为前进速度0.6 m/s、刀盘转速3000 r/min、割茬高度70 mm,并对该较优方案进行了验证试验,结果表明:设计的新型割草机在该方案下割茬稳定系数为93.2%,割幅利用率为99.3%,漏割率为0.5%,能满足郁闭果园实际作业要求。

关键词：割草机郁闭果园割茬高度调节株间避障遥控图传

维普期刊数据库博看期刊

在线全文

学校读者我要写书评

暂无评论

大数据时代高职院校课程质量诊断与改进研究

黑龙江教师发展学院学报 2024年第7期43卷 97-100页

作者：陈果刘霜霜刘志杰湖南工业职业技术学院长沙410001

随着大数据时代的不断发展,职业人才的教育培养环境得到了显著改善。数据决策、数据分析及数据整合逐渐成为高职院校课程体系建设的重要组成部分。通过运用大数据技术,教育培养环境更加智能化、个性化,为职业人才的培养提供了有力支持... 详细信息

随着大数据时代的不断发展,职业人才的教育培养环境得到了显著改善。数据决策、数据分析及数据整合逐渐成为高职院校课程体系建设的重要组成部分。通过运用大数据技术,教育培养环境更加智能化、个性化,为职业人才的培养提供了有力支持。高职院校课程质量的诊断,也要基于大数据技术的运用,增强课程质量诊断的科学性与针对性,通过对课程教学方法及教育模式的改进实现对教学有效性的提升,并利用统一质量诊断标准、加强数据信息筛选,以及深化教育信息反馈等多种策略,增强高职院校课程教学成果的转化能力。

关键词：高职院校课程质量诊断基础流程内在支撑诊断策略改进措施

北江水源自来水厂行走式板框压滤机污泥脱水研究

在线全文

学校读者我要写书评

暂无评论

中国给水排水 2024年第15期40卷 55-60页

作者：沈玉东李秋刘智皆陈伟雄李路野广东省建筑设计研究院有限公司广东广州510010 广州市花都自来水有限公司广东广州510000

通过分析北江水源自来水厂浓缩污泥的特性,探讨了行走式板框压滤机用于污泥脱水的效果。结果发现,使用阳离子、低离子度、粉剂型聚丙烯酰胺作为污泥调理药剂对板框压滤脱水效率具有显著的提升效果,同时针对进泥含固率为5%的浓缩污泥,当... 详细信息

通过分析北江水源自来水厂浓缩污泥的特性,探讨了行走式板框压滤机用于污泥脱水的效果。结果发现,使用阳离子、低离子度、粉剂型聚丙烯酰胺作为污泥调理药剂对板框压滤脱水效率具有显著的提升效果,同时针对进泥含固率为5%的浓缩污泥,当进料时间为10 min、进料压强为0.5 MPa、隔膜挤压压强为1.5 MPa时,建议挤压时间为35 min。

关键词：自来水厂行走式板框压滤机污泥脱水北江水源

基于土地利用结构的河流岸带生态系统服务簇识别

在线全文

学校读者我要写书评

暂无评论

水生态学杂志 2024年第3期45卷 52-59页

作者：徐慧高雨慧周强闫怀春蔡晨茵刘志杰河海大学水文水资源学院江苏南京210098 江苏省水土保持生态环境监测总站江苏南京210012

为识别河流岸带土地利用与生态服务价值的空间结构,从河流岸带保护角度选取水资源保护、净化环境、水文调节、土壤保持、维持养分循环、生物多样性6项生态服务功能,基于遥感影像解译的土地利用数据,运用修正的当量因子法估算得到生态服... 详细信息

为识别河流岸带土地利用与生态服务价值的空间结构,从河流岸带保护角度选取水资源保护、净化环境、水文调节、土壤保持、维持养分循环、生物多样性6项生态服务功能,基于遥感影像解译的土地利用数据,运用修正的当量因子法估算得到生态服务价值的空间分布规律,进而进行层次聚类分析识别河流岸带生态服务簇,并应用于太湖流域湖西区溧阳市县级河流——竹箦河作为实例研究。结果表明:(1)竹箦河河岸带6项生态服务价值呈现出显著的空间异质性和聚集性;(2)竹箦河河岸带可划分为5大类生态服务簇,分别为水源涵养型、绿色多元型、经济生态型、生态脆弱型以及耗水污染型;(3)各类服务簇的生态系统服务特点与空间布局分异明显,与岸带实际土地利用结构相协调,揭示了竹箦河河岸带生态服务功能普遍较薄弱的现状。研究结果可为竹箦河及类似平原地区骨干河流岸带功能区划分以及河岸带生态保护与修复方案的制定提供理论参考。

关键词：河岸带土地利用结构生态系统服务簇层次聚类分析

同方期刊数据库博看期刊评论

在线全文

学校读者我要写书评

暂无评论

产教融合背景下教师企业实践的理念研究

教育教学论坛 2024年第30期 59-62页

作者：刘志杰张梅丽李颖石家庄邮电职业技术学院人事处河北石家庄050021

教师企业实践是高职院校“双师型”教师队伍建设的基础,高水平“双师型”教师队伍是推动职业教育高质量发展的重要保障。从研究教师企业实践政策入手,系统分析了教师企业实践中政策体系不健全、教师实践意愿不强等问题,基于教师成长发... 详细信息

教师企业实践是高职院校“双师型”教师队伍建设的基础,高水平“双师型”教师队伍是推动职业教育高质量发展的重要保障。从研究教师企业实践政策入手,系统分析了教师企业实践中政策体系不健全、教师实践意愿不强等问题,基于教师成长发展理论创新性提出了构建“政—行—企—校”四方联动产教生态思维,构建基于校企利益诉求的耦合共赢模型等教师企业实践新理念,为教育行政部门和高职院校推进教师企业实践工作提供参考。

关键词：企业实践政策研究新理念新内涵

Green synthesis of luminescent La-MOF nanoparticle from waste poly(ethylene terephthalate) for high-performance in Fe(Ⅲ) detection

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2024年第8期43卷 3833-3843页

作者： zhi Gong zhi-Kui Dai zhi-Yue Dong Qiu-Xuan liu Valentin A.Milichko Hua-Jian liu jie liu Ran Niu Jiang Gong Key Laboratory of Material Chemistry for Energy Conversion and Storage Hubei Key Laboratory of Material Chemistry and Service FailureHubei Engineering Research Center for Biomaterials and Medical Protective MaterialsSemiconductor Chemistry CenterSchool of Chemistry and Chemical EngineeringMinistry of EducationHuazhong University of Science and TechnologyWuhan 430074China School of Chemical Engineering and Pharmacy Wuhan Institute of TechnologyWuhan 430073China Collaborative Innovation Center for Advanced Organic Chemical Materials Co-constructed by the Province and Ministry Ministry of Education Key Laboratory for the Synthesis and Application of Organic Functional Molecules and College of Chemistry and Chemical EngineeringHubei UniversityWuhan 430062China School of Physics and Engineering ITMO UniversitySt.Petersburg197101Russia School of Materials Science and Engineering Hubei UniversityWuhan430062China Guangdong Provincial Key Laboratory of Technique and Equipment for Macromolecular Advanced Manufacturing School of Mechanical and Automotive EngineeringKey Laboratory of Polymer Processing EngineeringMinistry of EducationSouth China University of TechnologyGuangzhou 510641China

Developing luminescent metal-organic frameworks(MOFs) capable of high-efficiency Fe^(3+)sensing has aroused great attraction in the fields of biology,chemistry,***,previous solvothermal methods are limited by organic solvent usage,time consuming,high pressure,and high-energy ***,we propose the waste-toMOF strategy towards the scale-up production of La-MOF nanoparticles through the ball milling of recycled poly(-ethylene terephthalate)(PET) bottles and La(NO_(3))_(3)·_(6)H_(2)*** goes on alkaline hydrolysis to form 1,4-benzenedicarboxylic acid sodium salt(Na_(2)BDC) and ethylene glycol by ball ***,BDC reacts with La^(3+)to form *** as-prepared La-MOF crystal nanoparticles possess a rod-like morphology with the size of few hundred ***,La-MOF nanoparticles display high selectivity and sensitivity for Fe^(3+)*** quenching constant and limit of detection are 5.29×10^(3)(mol·L^(-1))^(-1) and 0.147 μmol·L^(-1),respectively,thus surpassing many advanced Fe^(3+) *** to the result of density functional theory,the high Fe^(3+) detection performance of La-MOF is related to the complexing of Fe^(3+)with La-MOF,which leads to the gradual dissociation of the coordination bond between terephthalic acid and La^(3+).It is anticipated that the mechanochemistry milling-based wasteto-MOF strategy provides a new platform for the massive production of functional MOFs in a green manner.

关键词： Metal-organic framework Waste polyester Mechanochemistry milling Fluorescence sensor

Prediction for permeability index of blast furnace based on VMD-PSO-BP model

在线全文

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2024年第3期31卷 573-583页

作者： Xiao-jie liu Yu-jie Zhang Xin Li zhi-feng Zhang Hong-yang Li Ran liu Shu-jun Chen School of Metallurgy and Energy North China University of Science and TechnologyTangshan 063210HebeiChina Chengde Branch HBIS Group Co.Ltd.Chengde 067000HebeiChina

The permeability index is one of the important production indicators to monitor the operation of blast *** is crucial to grasp the trends of changes in the new permeability index in *** the complex vibration spectrum of the permeability index,a prediction model of the permeability index based on the VMD-PSO-BP(variational mode decomposition-particle swarm optimization-back propagation)method was ***,the key factors that affect the permeability index of blast furnace were studied from multiple ***,the permeability index was divided into multiple sub-modes based on the difference of frequency bands by the VMD algorithm,and a PSO-BP prediction model was established for each ***,the prediction results of each sub-mode were summed to obtain the final *** results show that the composite prediction accuracy by using the VMD algorithm is 3%higher than that of the traditional prediction method,which has better applicability.

关键词： Big data-Blast furnace Air permeability Variational mode decomposition Particle swarm optimization Back propagation Model prediction

Magnetic emission intensity enhancement for amorphous alloys by constructing a multi-phase structure withα-Fe nanocrystals

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nano Research 2024年第7期17卷 6630-6637页

作者： Ke liu zhi Qin jie Shen zhi Cheng Shiyue You Liang Ma Jing Zhou Wen Chen State Key Laboratory of Advanced Technology for Materials Synthesis and Processing School of Materials Science and EngineeringWuhan University of TechnologyWuhan 430070China Sanya Science and Education Innovation Park Wuhan University of TechnologySanya 572024China Hubei Longzhong Laboratory Wuhan University of Technology Xiangyang Demonstration ZoneXiangyang 441000China

The perturbation in the magnetic field generated by the rotation or oscillation of magnetic domains in magnetic materials can emit low-frequency electromagnetic waves,which are expected to be used in low-frequency ***,the magnetic emission intensity,defined by the perturbation ability,of current commercially applied amorphous alloys,such as Metglas,cannot meet the application requirements for low-frequency antennas due to the domain motion energy ***,a multi-phase Metglas amorphous alloy was constructed by incorporatingα-Fe nanocrystals using rapid annealing to manipulate the domain *** was found that 3.89 times higher magnetic emission intensity is obtained compared to the pristine due to the synergism of the deformation and displacement ***,the low-frequency magnetic emission performance verification was carried out by preparing magnetoelectric composites as the antenna vibrator by assembling the alloy and macro piezoelectric fiber composites(MFC).Enhancements of magnetic emission intensity are found at 93.3%and 49.2%at the first and second harmonic frequencies compared with the unmodified alloy ***,the approach leads to the development of high-performance communication with a novel standard for evaluation.

关键词： multi-phase amorphous alloys magnetic emission intensity enhancing mechanism magnetic domain pinning theory Jiles-Atherton model analysis