Design and optimization of fluid lubricated bearings operated with extreme working performances——a comprehensive review

Fluid lubricated bearings have been widely adopted as support components for high-end equipment in metrology,semiconductor devices,aviation,strategic defense,ultraprecision manufacturing,medical treatment,and power generation.In all these applications,the equipment must deliver extreme working performances such as ultraprecise movement,ultrahigh rotation speed,ultraheavy bearing loads,ultrahigh environmental temperatures,strong radiation resistance,and high vacuum operation,which have challenged the design and optimization of reliable fluid lubricated bearings.Breakthrough of any related bottlenecks will promote the development course of high-end equipment.To promote the advancement of high-end equipment,this paper reviews the design and optimization of fluid lubricated bearings operated at typical extreme working performances,targeting the realization of extreme working performances,current challenges and solutions,underlying deficiencies,and promising developmental directions.This paper can guide the selection of suitable fluid lubricated bearings and optimize their structures to meet their required working performances.

Application of the Industry-University-Research Education Model of“Works,Products,and Public Goods”in Design Majors Practical Courses in Colleges and Universities

One of the goals and requirements of China’s educational modernization includes prioritizing,guiding,and promoting the social service capabilities of universities.The teaching of practical courses in design majors in colleges and universities has long been plagued by problems such as being“out of touch with the market and social needs”and“ignoring the cultivation of creativity.”It fails to meet the goals and requirements of educational modernization.This article takes the“Fundamentals of Styling and Comprehensive Expression”course offered by the School of Design of Guangxi Normal University as an entry point to study the industry-university-research education method that combines“social service”with the teaching of design professional practical courses.It also attempts to improve“works,products,and public goods”through the establishment of the theoretical model of“product”and the analysis of practical application paths is carried out to solve the problems existing in the traditional teaching of the design major,enhance the social service capabilities of the design major,promote talent employment and industry and social development,and carry out teaching reform attempts.

基于SolidWorks二次开发的平面闸门工程图出图研究

文章以平面闸门工程图三维正向设计出图为研究目的,系统性地梳理了平面闸门三维建模和工程图出图流程及方法,提出建模原则和方式,利用SolidWorks API接口进行二次开发,解决了工程图中材料明细表和焊接切割清单统计问题,开发了金属结构专业工程图插件软件,显著提高了工程图出图效率和质量。

Flexible Fixture Design for the Top and End Surface Processing of NP2_NP4 Cylinder Heads

This paper focuses on the design of fixtures for NP2 and NP4 cylinder heads on a horizontal machining center of flexible machining automatic lines.It began with an analysis of the diagrams of part processing and working procedure which formed the basis for the design of the processing technology scheme,a selection of suitable machine tools,and the setting of processing parameters.Fixtures tailored to the chosen machine tools were then designed to meet the processing requirements.Additional aspects of the project included the design of part drawings,calculation of working time quota,design of auxiliary guides,support clamping,and hydraulic circuits,all aimed at fulfilling practical production requirements.

A Framework for Web-Based Mechanical Design and Analysis

In this paper, a Web-based Mechanical Design and A na lysis Framework (WMDAF) is proposed. This WMADF allows designers to develop web -based computer aided programs in a systematic way during the collaborative mec hanical system design and analysis process. This system is based on an emerg ing web-based Content Management System (CMS) called eXtended Object Oriented P ortal System (XOOPS). Due to the Open Source Status of the XOOPS CMS, programs d eveloped with this framework can be further customized to satisfy the demands of the user. To introduce the use of this framework, this paper exams three differ ent types of mechanical design and analysis problems. First, a repetitive design consideration and calculation process is transferred into WMADF programs to gai n efficiency for wired collaborative team. Second, the considered product solid model is created directly through the use of XOOPS program and Microsoft Compone nt Object Model (COM) instances. To the end of the paper, an example linked with ANSYS is used to indicate the possible application of this framework.

Multifunctional Perovskite Photodetectors: From Molecular-Scale Crystal Structure Design to Micro/Nano-scale Morphology Manipulation

Multifunctional photodetectors boost the development of traditional optical communication technology and emerging artificial intelligence fields, such as robotics and autonomous driving. However, the current implementation of multifunctional detectors is based on the physical combination of optical lenses, gratings, and multiple photodetectors, the large size and its complex structure hinder the miniaturization, lightweight, and integration of devices. In contrast, perovskite materials have achieved remarkable progress in the field of multifunctional photodetectors due to their diverse crystal structures, simple morphology manipulation, and excellent optoelectronic properties. In this review, we first overview the crystal structures and morphology manipulation techniques of perovskite materials and then summarize the working mechanism and performance parameters of multifunctional photodetectors. Furthermore, the fabrication strategies of multifunctional perovskite photodetectors and their advancements are highlighted, including polarized light detection, spectral detection, angle-sensing detection, and selfpowered detection. Finally, the existing problems of multifunctional detectors and the perspectives of their future development are presented.

Research and Design of IPv6 Network Management and Operations Support System

IPv6 is the foundation of the development of Next Generation Internet (NGI). An IPv6 network management and operations support system is necessary for real operable NGI. Presently there are no approved standards yet and relevant equipment interfaces are not perfect. A Network Management System (NMS) at the network layer helps implement the integrated management of a network with equipment from multiple vendors, including the network resources and topology, end-to-end network performance, network failures and customer Service Level Agreement (SLA) management. Though the NMS will finally realize pure IPv6 network management, it must be accommodated to the management of relevant IPv4 equipment. Therefore, modularized and layered structure is adopted for the NMS in order to implement its smooth transition.

FY-2C Working Normally Beyond Design Lifetime

The FY-2C meteorological satellite had been working well for 8 years as of October 19, 2012. Though the satellite was originally designed to work for 3 years, it still operates steadily. As the nation's first operational first-generation geo- stationary meteorological satellite, FY-2C works together with the following satellites FY-2D, FY-2E and FY-2F, in a operational mode of two operational plus two backup ones. FY-2C, FY-2D and FY-2E were the second batch satellites of FY-2 series

基于Solid Works的转盘式沙漠种植机设计

针对当前市面上的沙漠种植机械品类少、设备笨重、工序单一、需要多人辅助作业且树苗的成活率难以保证,该文为直径为1~2 cm、高35~55 cm的树苗,设计一款自动化程度高、操作简单的转盘式沙漠种植机。该设备使用Solid Works2019软件对其机械结构进行设计,整体设备包括钻孔单元、旋转盘植树单元、覆土单元和设备车体;使用Adams 2016软件对其钻孔单元进行动态仿真分析,确保其尺寸设计的合理性。

运动解耦且大工作空间三平移机构拓扑设计

根据基于方位特征(POC)方程的并联机构拓扑设计方法和运动解耦设计原理,提出一个运动解耦性优异的单回路三平移子并联机构;设计一类4个具有正向位置符号化、部分运动解耦性且具有较大工作空间的三平移(3T)并联机构;对这类机构进行拓扑特性分析,得到相同的方位特征集(POC)、自由度(DOF)、耦合度(κ)、运动解耦性等主要拓扑特性;对其中一个机构进行运动学、动力学性能分析。根据基于拓扑特征运动学建模原理,求出其符号化位置正反解,以及速度、加速度曲线;基于推导出的位置逆解公式,分析机构的奇异位形及工作空间;根据基于序单开链的虚功原理,进行其动力学建模与分析,求解出机构的驱动力。

考虑多工况的甘蔗收割机回转台轻量化研究

甘蔗收割机回转台在工作过程中承受过双侧凹坑、转向过坑等工况载荷及扭矩的作用,受力复杂,优化时需要多工况综合考虑。ESO多工况优化方法由于未考虑不同工况间的重要程度,不易获得全局最优解。因此提出一种多目标拓扑优化函数,采用带权重的线性加权法协调多个目标函数,构建多工况拓扑优化数学模型,运用层次分析法确定各工况的权重系数,基于inspire软件对回转台进行多目标拓扑优化,从而获得材料的最优分布。优化结果表明:优化后回转台结构最大应力与最大位移均有所下降且满足强度与刚度要求,实现了多目标同时优化。

全国城乡规划专业城市设计课程作业竞赛的分析与思考

“城市设计课程作业评优”是全国城乡规划专业最高层次、最为规范、最受认可的一项设计竞赛。以2005年—2019年的竞赛获奖名单为样本,根据教学发展过程与城市设计发展的关键时间节点,将竞赛历程分为前期、中期、后期3个阶段,对竞赛的总体获奖情况、获奖院校的地域分布与院校类型特征、设计竞赛与获奖作品的主题特点进行了统计分析与交叉分析,从整体上把握其变化发展趋势。基于分析结果的思考,认为我国的城市设计课程教学应从以下四个方面做进一步的探索:坚持开放融合,共促共进的教学理念;构建“城市空间形态设计+”的教学内容;采用引入研究的设计教学方法;建立多元化的教学成果评估方式。

桃源漆艺木雕瑞兽模件化特征及设计应用研究

桃源漆艺木雕中瑞兽较多,但已有研究中未见缘由。通过文献查阅、比较研究发现“八蛮进宝”是其文化根源,在历史进程中瑞兽演化成为桃源典型的模件化装饰母题,其中具表情欢愉模件化造型特征的被普称为“欢兽”,以狮子、独角兽、麒麟为最。在提倡文化活态传承的背景下,以极具特色的欢兽头部为原型,以通用化、系列化、模块化“三化法”为设计原则,运用扁平化及解构设计方法,设计欢兽IP形象及其欢兽IP鬃毛、耳、五官构件,并通过材料转换、结构可变、功能可收纳的设计,实现用户自由创意欢兽造型的交互体验价值,以达到桃源漆艺木雕瑞兽文化在当代生活中活化的目的。

《营造法式》大木作“缝”内涵考释(一):综述与文本

《营造法式》大木作各卷文本及图样皆有“缝”的记述与标记,对其进行归纳与分析,发现“缝”具有重要的构造设计内涵。本文首先整理学界已有相关注释与专述,归纳出关于“缝”的多类观点。通过对《营造法式》文本记述内容的考释,揭示出大木作“缝”的两类基本内涵,着重关注“缝”对空间形态与空间尺度的构造控制作用,及其构造设计性质。

智能手指关节功能康复训练器创新结构设计

因运动、年龄老化等因素导致手指功能损伤患者数量不断增加。针对这类人群进行手指康复器的设计,与传统康复产品相比,具有控制简单、方便、成本相对较低特点。通过分析仿手指运动的自由度,建立了曲柄摇杆机构,可以应用于手指康复器的结构设计;以主要机械构件和手指关节转动角度为参考因素,得出了机构的运动轨迹,在此基础上,得到各机械构件的合理尺寸,从而完成对机械构件的结构设计。通过模拟手指拉伸、弯曲来实现手指的康复功能。通过分析运动的角位移、角速度使得所得的机构更加符合手指的合理运动范围。运动仿真实验表明,该机构能带动手指在一定角度范围进行弯曲拉伸运动,可以满足手指损伤患者的康复训练需求。

一种新型振弦式土压力盒的结构设计分析

在我国,岩土工程领域十分广阔,工程的应力检测、监测显得尤为重要。检测岩土基础的应力变化所用的土压力盒、土压力计种类繁多,有些土压力盒原理相同但结构多样,还有些土压力盒标定方法与实际应用完全不符。基于此,提出一种能够符合现场埋设应用的振弦式土压力盒。该设计是轮辐式工作膜在无盒状态下只接受压力传递片的压力和校准方法。

基于工作过程的“机械制造工艺与夹具”课程线上线下混合式教学设计研究

文章结合国内现有的“机械制造工艺与夹具”课程教学研究成果和教学经验,基于课情和学情分析,从总体思路、课程思政、教学内容、教学模式及组织形式、教学方法手段及重难点突破、技能训练项目任务书、教学评价等7个维度,探讨了一种基于工作过程、岗课赛证一体融通的“机械制造工艺与夹具”课程线上线下混合式教学设计。经三年的教学实践证明,效果明显优于以往的教学设计。

基于文艺作品的黑龙江红色旅游资源开发

黑龙江地域文艺作品展现的红色文旅资源丰富。分析基于文艺作品开发黑龙江红色旅游路线的可行性,提出文学作品红色资源“情景再现”设计,开发文学作品专线旅游版图构建,可为其他地域的红色旅游提供参考。

中江气田井间气举优化研究

中江气田自建产投入开发以来,采取衰竭式开发模式,同时部分单井产量、地层能量较低,而产液量大,井底积液严重。井间气举工艺简单、原理简明,利用了井间生产差异的特点,充分利用现有地质资源,对积液气井进行辅助排水采气作业效果较好,具有效益好、投资小的特点。对于地层持续出液气井,气举原则为适当补压,少量多次,辅助排液,确保气井平稳生产,不波动。通过软件模拟、数据计算与现场试验相结合,更改工作制度逐渐找到最适气举参数(流量、压力、频率、时长),从而提高举升效率。并根据气举时压力、流量变化可将气举阶段划分为注气阶段、增压阶段、排液阶段、余压气举阶段、正常生产阶段,对此后井间气举工作开展起到一定指导作用。

安百拓液压凿岩机活塞受力面积分析与三段法述评

搜集了11个安百拓双控式凿岩机和4个后控式凿岩机冲击活塞的直径数据,计算得到在凿岩机冲击运动周期中,回程与冲程活塞受力面积的比值范围。根据比值数据的分析,指出基于三段法理论的设计变量作为凿岩机性能评价指标的普适性较差。据此,本文强调了数据分析在凿岩机研究中的重要作用。文中还介绍了改进的三段法理论及其计算实例,论述了改进的三段法的优点与缺点。