检索结果-南通市图书馆

Energy and Built Environment 2024年第2期5卷 255-269页

作者： Ping Cui Weibo Yang Wenke Zhang Ke Zhu Jeffrey D.Spitler mingzhi yu School of Thermal Engineering Shandong Jianzhu UniversityJinanShandong 250101China College of Electrical Energy and Power EngineeringYangzhou UniversityYangzhouJiangsu 225127China Department of Mechanical Engineering Oklahoma State UniversityStillwaterOKUSA

As a renewable energy source,geothermal energy has been widely used to provide space heating and cooling for buildings.The thermal performance of ground heat exchanger(GHE)is significant for the operating efficiency of the ground source heat pump(GSHP)systems.This paper presents a comprehensive review of developments and advances of three kinds of GHE,including vertical borehole GHE(VBGHE),Pile GHE(PGHE),and deep borehole GHE(DBGHE)which are currently popular in larger GSHP systems.Firstly,analytical models proposed to ana-lyze heat transfer process of VBGHE with different geological conditions are summarized,such as homogenous or heterogeneous ground,with or without groundwater advection.Numerical and short-time step models and measures to improve GHE thermal performance are also reviewed.Secondly,a summary of research advances in PGHE is provided,which includes the heat transfer models of PGHE,the effects of geometric structure,oper-ation modes,pile spacing,use of phase change material(PCM),thermal properties of PCM,thermo-mechanical behavior and/or thermal performance of PGHE.The effects of groundwater flow direction and velocity on PGHE are also summarized in brief.Lastly,models of three kinds of DBGHEs,i.e.,deep coaxial GHE(DCGHE),deep U-bend GHE(DUGHE)and super-long gravity heat pipe(SLGHP),are reviewed.The physical bases of the dif-ferent analytical models are elaborated and also their advantages and disadvantages are described.Advances in numerical modelling and improving numerical model calculation speed of DCBHE,DCBHE array,and DUBHE are summarized.The review provides a meaningful reference for the further study of GHEs.

关键词： Vertical borehole ground heat exchanger Pile ground heat exchanger Deep borehole ground heat exchanger Modelling

来源：

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

基于创新性内侧壁成型工艺的多光学通道微型碱金属原子气室

引用

Engineering 2024年第4期35卷 46-55页

作者： mingzhi yu Yao Chen Yongliang Wang Xiangguang Han Guoxi Luo Libo Zhao Yanbin Wang Yintao Ma Shun Lu Ping Yang Qijing Lin Kaifei Wang Zhuangde Jiang International Joint Laboratory for Micro/Nano Manufacturing and Measurement Technologies Xi’an Jiaotong UniversityXi’an 710049China School of Mechanical Engineering Xi’an Jiaotong UniversityXi’an 710049China Shandong Laboratory of Yantai Advanced Materials and Green Manufacturing Yantai 265503China Moon Environment Technology Co. Ltd.Yantai 264000China Emergency Department The First Affiliated Hospital of Xi’an Jiaotong UniversityXi’an 710061China

Existing microfabricated atomic vapor cells have only one optical channel,which is insufficient for supporting the multiple orthogonal beams required by atomic devices.In this study,we present a novel wafer-level manufacturing process for fabricating multi-optical-channel atomic vapor cells and an innovative method for batch processing the inner sidewalls of millimeter glass holes to meet optical channel requirements.Surface characterization and transmittance tests demonstrate that the processed inner sidewalls satisfy the criteria for an optical channel.In addition,the construction of an integrated processing platform enables multilayer non-isothermal anode bonding,the filling of inert gases,and the recovery and recycling of noble gases.Measurements of the absorption spectra and free-induction decay signals of xenon-129(^(129)Xe)and xenon-131(^(131)Xe)under different pump-probe schemes demonstrate the suitability of our vapor cell for use in atomic devices including atomic gyroscopes,dual-beam atomic magnetometers,and other optical/atomic devices.The proposed micromolding technology has broad application prospects in the field of optical-device processing.

关键词： Microfabricated atomic vapor cells Inner-sidewall molding Multiple optical channels Quantum sensing

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Osteogenic and antibacterial ability of micro-nano structures coated with ZnO on Ti-6Al-4V implant fabricated by two-step laser processing

引用

Journal of Materials Science & Technology 2022年第36期131卷 240-252页

作者： Yi Wan Zihe Zhao mingzhi yu Zhenbing Ji Teng Wang yukui Cai Chao Liu Zhanqiang Liu Key Laboratory of High Efficiency and Clean Manufacturing School of Mechanical EngineeringShandong UniversityJinan 250061China Department of Oral and Maxilofacial Surgery Qilu Hospital of Shandong UniversityJinan 250012China Centre of Micro/Nano Manufacturing Technology(MNMT-Dublin) School of Mechanical and Materials EngineeringUniversity College DublinDublin D04 KW52Ireland School of Engineering Sciences in Chemistry Biotechnology and HealthKTH RoyalInstitute of TechnologyStockholmStockholm S-10044Sweden Department of Oral Surgery Shanghai Ninth People’s HospitalShanghai Jiao Tong University School of MedicineCollege of StomatologyShanghai Jiao Tong UniversityNational Center for StomatologyNational Clinical Research Center for Oral DiseasesShanghai Key Laboratory of StomatologyShanghai 200011China

The biological performance of Ti-6Al-4V implant is primarily determined by their surface properties.However,traditional surface modification methods,such as acid etching,hardly make improvement in their osseointegration ability and antibacterial capacity.In this study,we prepared a multi-scale composite structure coated with zinc oxide(ZnO)on Ti-6Al-4V implant by an innovative technology of two-step laser processing combined with solution-assistant.Compared with the acid etching method,the physicochemical properties of surface significantly improved.The in vitro results showed that the particular dimension of micro-nano structure and the multifaceted nature of ZnO synergistically affected MC3T3-E1 osteogenesis and bacterial activities:(1)The surface morphology showed a‘contact guidance'effect on cell arrangement,which was conducive to the adhesion of filopodia and cell spreading,and the osteogenesis level of MC3T3-E1 was enhanced due to the release of zinc ions(Zn^(2+));(2)the characterization of bacterial response revealed that periodic nanostructures and Zn^(2+)released could cause damage to the cell wall of E.coli and reduce the adhesion and aggregation of S.aureus.In conclusion,the modified surface showed a synergistic effect of physical topography and chemical composition,making this a promising method and providing new insight into bone defect repairment.

关键词： Ti-6Al-4V implant Laser processing Micro-nano structure Zinc oxide Osseointegration ability Antibacterial capacity

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Multiscale design and biomechanical evaluation of porous spinal fusion cage to realize specified mechanical properties

引用

Bio-Design and Manufacturing 2022年第2期5卷 277-293页

作者： Hongwei Wang Yi Wan Quhao Li Xinyu Liu mingzhi yu Xiao Zhang Yan Xia Qidong Sun Zhanqiang Liu Key Laboratory of High Efficiency and Clean Manufacturing School of Mechanical EngineeringShandong UniversityJinan 250061China National Demonstration Center for Experimental Mechanical Engineering Education School of Mechanical EngineeringShandong UniversityJinan 250061China Department of Orthopedics Qilu Hospital of Shandong UniversityJinan 250012China

Backgrou nd Dense titanium(Ti)fusion cages have been commonly used in transforaminal lumbar interbody fusion.However,the stiffness mismatch between cages and adjacent bone endplates increases the risk of stress shielding and cage subsidence.Methods The current study presents a multiscale optimization approach for porous Ti fusion cage development,including microscale topology optimization based on homogenization theory that obtains a unit cell with prescribed mechanical properties,and macroscale topology optimization that determines the layout of framework structure over the porous cage while maintaining the desired stiffness.The biomechanical performance of the designed porous cage is assessed using numerical simulations of fusion surgery.Selective laser melting is employed to assists with fabricating the designed porous structure and porous cage.Results The simulations demonstrate that the designed porous cage increases the strain energy density of bone grafts and decreases the peak stress on bone endplates.The mechanical and morphological discrepancies between the as-designed and fabricated porous structures are also described.Conclusion From the perspective of biomechanics,it is demonstrated that the designed porous cage contributes to reducing the risk of stress shielding and cage subsidence.The optimization of processing parameters and post-treatments are required to fabricate the designed porous cage.The present multiscale optimization approach can be extended to the development of cages with other shapes or materials and further types of orthopedic implants.

关键词： Topology optimization Finite element method Porous fusion cage Lumbar spine Selective laser melting

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Monolithically integrated triaxial high-performance micro accelerometers with position-independent pure axial stressed piezoresistive beams

引用

Microsystems & Nanoengineering 2023年第1期9卷 91-102页

作者： mingzhi yu Libo Zhao Shanshan Chen Xiangguang Han Chen Jia Yong Xia Xiaozhang Wang Yonglu Wang Ping Yang Dejiang Lu Zhuangde Jiang State Key Laboratory for Manufacturing Systems Engineering International Joint Laboratory for Micro/Nano Manufacturing and Measurement TechnologiesXi’an Jiaotong University710049Xi’anChina Xi’an Jiaotong University(Yantai)Research Institute for Intelligent Sensing Technology and System Xi’an Jiaotong University710049Xi’anChina Shandong Laboratory of Yantai Advanced Materials and Green Manufacturing 265503YantaiChina

With the increasing demand for multidirectional vibration measurements,traditional triaxial accelerometers cannot achieve vibration measurements with high sensitivity,high natural frequency,and low cross-sensitivity simultaneously.Moreover,for piezoresistive accelerometers,achieving pure axial deformation of the piezoresistive beam can greatly improve performance,but it requires the piezoresistive beam to be located in a specific position,which inevitably makes the design more complex and limits the performance improvement.Here,a monolithically integrated triaxial high-performance accelerometer with pure axial stress piezoresistive beams was designed,fabricated,and tested.By controlling synchronous displacements at both piezoresistive beam ends,the pure axial stress states of the piezoresistive beams could be easily achieved with position independence without tedious calculations.The measurement unit for the z-axis acceleration was innovatively designed as an interlocking proof mass structure to ensure a full Wheatstone bridge for sensitivity improvement.The pure axial stress state of the piezoresistive beams and low cross-sensitivity of all three units were verified by the finite element method(FEM).The triaxial accelerometer was fabricated and tested.Results showing extremely high sensitivities(x axis:2.43 mV/g/5 V;y axis:2.44 mv/g/5 V;z axis:2.41 mV/g/5 V(without amplification by signal conditioning circuit))and high natural frequencies(x/y axes:11.4 kHz;z-axis:13.2 kHz)were obtained.The approach of this paper makes it simple to design and obtain high-performance piezoresistive accelerometers.

关键词： axial proof independence

来源：

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

基于新型元启发式BP神经网络的500kV覆冰输电线路力学响应预测研究

引用

应用基础与工程科学学报 2024年第1期32卷 100-122页

作者：苏仁斌熊卫红刘先珊张林于明智周庆曹明宇国家电网有限公司华中分部湖北武汉430072 重庆大学土木工程学院重庆400045 国网重庆市电力公司电力科学研究院重庆401121 重庆大学计算机学院重庆400045 国网湖南超高压输电公司湖南衡阳421002

覆冰高压输电线路塔体高、跨度大,断线、倒塔、舞动等事故频发,现有的监测设备量少,不足以及时反映其力学响应特征,提高覆冰线路的事前预警准确性是运维关键.以某500kV典型覆冰塔线体系为研究对象,结合在线监测信息验证该模型的合理性,... 详细信息

覆冰高压输电线路塔体高、跨度大,断线、倒塔、舞动等事故频发,现有的监测设备量少,不足以及时反映其力学响应特征,提高覆冰线路的事前预警准确性是运维关键.以某500kV典型覆冰塔线体系为研究对象,结合在线监测信息验证该模型的合理性,基于三维有限元提出计算杆塔力学响应的代理模型,快速获得了不同覆冰工况的杆塔位移及应力值,形成力学响应数据库,并提出基于新型元启发式即浣熊优化算法(COA)BP神经网络的覆冰线路力学响应预测方法.对比了4种优化算法在23个测试函数中的进化能力、收敛速度及收敛精度,说明浣熊优化算法对复杂问题全局最优求解的高效性,并开展了不同训练样本数的正弦函数和余弦函数的仿真研究,阐明了COA进化神经网络计算更准确,且更快收敛于最优解.进一步,以覆冰输电线路力学响应的主控因子及塔顶位移为网络输入,以杆塔最大位移、最大拉应力及最大压应力为网络输出,基于风向角45°的监测数据集验证预测模型的学习泛化能力,并对比其他4种进化神经网络模型的预测值,再次阐明了该预测模型的优势.最后将该模型应用于风向角180°的塔线体系力学响应预测,其预测值均与实际覆冰工况的杆塔位移及应力值吻合,特别是不同覆冰工况的力学响应变化曲线再次验证了上述预测模型的可行性.可见,基于新型元启发式BP神经网络模型可实现覆冰高压塔线体系力学响应预测的实时性、高效性和准确性,为输电线路实时健康评估及事前预测预警提供了技术支持.

关键词：覆冰塔线体系新型元启发算法浣熊优化算法进化神经网络模型力学响应预测模型

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

尺寸效应下超快激光加热硅薄膜二维传热研究

引用

光电子．激光 2024年第5期35卷 552-560页

作者：毛煜东赵国晨杨开敏张其龙吕慧丽于明志山东建筑大学热能工程学院山东济南250101 华电电力科学研究院有限公司浙江杭州310030

超快激光技术目前较为广泛地应用于微纳米结构的加工,极小的尺寸产生了不同于宏观条件的传热特性,也逐渐成为人们研究的热点。文章采用改进双相滞导热(dual-phase-lagging,DPL)模型对超快激光照射纳米硅薄膜的二维传热过程展开了理论研... 详细信息

超快激光技术目前较为广泛地应用于微纳米结构的加工,极小的尺寸产生了不同于宏观条件的传热特性,也逐渐成为人们研究的热点。文章采用改进双相滞导热(dual-phase-lagging,DPL)模型对超快激光照射纳米硅薄膜的二维传热过程展开了理论研究。通过应用积分变化法求解了反映尺寸效应的改进DPL方程,分析了薄膜内部温度沿薄膜厚度方向和径向的变化规律。结果显示薄膜加热区域的温度迅速升高,随后能量会以波的形式逐渐向薄膜内部传递。在采用改进DPL模型得到的结果中热量的波状传递现象与DPL模型的结果相比更为平缓,将二维改进模型的结果同一维结果进行对比,发现在相同克努森数下,二维模型得到的温度要高于一维模型;且两者的差距会随着时间的推移愈发明显,表明二维传热过程中热量的径向传递对薄膜内部的温度分布具有重要影响。

关键词：超快激光加热尺寸效应双相滞导热(DPL)模型积分变换法

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

基于中医时间医学探讨昼夜节律对双相情感障碍的影响

引用

中国中医基础医学杂志 2024年第6期30卷 1037-1041页

作者：于明直钱越李宇盾刘玥芸陈家旭北京中医药大学中医学院北京100029

双相情感障碍是一种常见的精神障碍类疾病,其典型表现为生物节律紊乱。研究发现,双相情感障碍与生物节律紊乱二者互为因果,其中以严重的昼夜节律紊乱最为突出。中医时间医学以“天人相应”和“阴阳盛衰变化”为理论核心,强调四季昼夜变... 详细信息

双相情感障碍是一种常见的精神障碍类疾病,其典型表现为生物节律紊乱。研究发现,双相情感障碍与生物节律紊乱二者互为因果,其中以严重的昼夜节律紊乱最为突出。中医时间医学以“天人相应”和“阴阳盛衰变化”为理论核心,强调四季昼夜变化对人体生理及病理的影响,故昼夜节律紊乱对双相情感障碍的发生、治疗及转归具有重要意义。本文将“昼夜节律”理论与现代医学生物节律中的褪黑素分泌水平、下丘脑-垂体-肾上腺轴相结合,探讨“昼夜节律”在双相情感障碍中的生理作用及其在不同疾病阶段的病理变化,旨在为临床治疗双相情感障碍提供新的诊疗思路。

关键词：双相情感障碍中医时间医学昼夜节律褪黑素下丘脑-垂体-肾上腺轴

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

基于多数据源融合的电网故障判别与告警技术研究

引用

电气自动化 2024年第2期46卷 32-35,39页

作者：朱轶伦俞一峰虞明智杜晟炜姚高许杰浙江华云信息科技有限公司浙江杭州310007 国网浙江省电力有限公司浙江杭州310007 国网金华供电公司浙江金华321000

针对国家电网故障判别误差率较高的问题,设计一种基于多数据源融合的电网故障判别与告警方案。利用最大离散小波变换技术和长短期记忆网络算法结合的方法提高电网故障判别与告警能力;利用最大重叠离散小波变换技术具有的扩充冗余自成正... 详细信息

针对国家电网故障判别误差率较高的问题,设计一种基于多数据源融合的电网故障判别与告警方案。利用最大离散小波变换技术和长短期记忆网络算法结合的方法提高电网故障判别与告警能力;利用最大重叠离散小波变换技术具有的扩充冗余自成正交特性对故障类型进行划分;将长短期记忆网络算法由单向进程转为双向网络,避免了反馈传输过程中的网络层无法得到合适的偏导数等梯度消失情况。试验结果表明,通过所提算法进行数据质量核查的准确度高达九成以上,表明所提研究系统对解决提升故障判别准确度的提升具有较强的实用性、优越性。

关键词：故障判别最大重叠离散小波变换技术长短期记忆网络算法类型划分双向网络

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Development of a deviation package method for low-cost robust optimization in compressor blade design

引用

Chinese Journal of Aeronautics 2024年第4期37卷 166-180页

作者： mingzhi LI Xianjun yu Dejun MENG Guangfeng AN Baojie LIU Research Institute of Aero-Engine Beihang UniversityBeijing 100191China National Key Laboratory of Science&Technology on Aero-Engine Aero-Thermodynamics Beihang UniversityBeijing 100191China AECC Shenyang Engine Research Institute Shenyang 110015China

Manufacture variations can greatly increase the performance variability of compressor blades. Current robust design optimization methods have a critical role in reducing the adverse impact of the variations, but can be affected by errors if the assumptions of the deviation models and distribution parameters are inaccurate. A new approach for robust design optimization without the employment of the deviation models is proposed. The deviation package method and the interval estimation method are exploited in this new approach. Simultaneously, a stratified strategy is used to reduce the computational cost and assure the optimization accuracy. The test case employed for this study is a typical transonic compressor blade profile, which resembles most of the manufacture features of modern compressor blades. A set of 96 newly manufactured blades was measured using a coordinate measurement machine to obtain the manufacture variations and produce a deviation package. The optimization results show that the scatter of the aerodynamic performance for the optimal robust design is 20% less than the baseline value. By comparing the optimization results obtained from the deviation package method with those obtained from widely-used methods employing the deviation model, the efficiency and accuracy of the deviation package method are demonstrated. Finally, the physical mechanisms that control the robustness of different designs were further investigated, and some statistical laws of robust design were extracted.

关键词： Manufacture variations Robust design optimization Compressor leading edge Aerodynamics Physical mechanism

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：