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Deep-Learning-Coupled Numerical Optimization Method for Designing Geometric Structure and Insertion-Withdrawal Force of Press-Fit Connector
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作者 Mingzhi Wang Bingyu Hou Weidong Wang 《Acta Mechanica Solida Sinica》 2025年第1期78-90,共13页
The press-fit connector is a typical plug-and-play solderless connection,and it is widely used in signal transmission in fields such as communication and automotive devices.This paper focuses on inverse designing and ... The press-fit connector is a typical plug-and-play solderless connection,and it is widely used in signal transmission in fields such as communication and automotive devices.This paper focuses on inverse designing and optimization of geometric structure,as well as insertion-withdrawal forces of press-fit connector using artificial neural network(ANN)-assisted optimization method.The ANN model is established to approximate the relationship between geometric parameters and insertion-withdrawal forces,of which hyper-parameters of neural network are optimized to improve model performance.Two numerical methods are proposed for inverse designing structural parameters(Model-I)and multi-objective optimization of insertion-withdrawal forces(Model-II)of press-fit connector.In Model-I,a method for inverse designing structure parameters is established,of which an ANN model is coupled with single-objective optimization algorithm.The objective function is established,the inverse problem is solved,and effectiveness is verified.In Model-II,a multi-objective optimization method is proposed,of which an ANN model is coupled with genetic algorithm.The Pareto solution sets of insertion-withdrawal forces are obtained,and results are analyzed.The established ANN-coupled numerical optimization methods are beneficial for improving the design efficiency,and enhancing the connection reliability of the press-fit connector. 展开更多
关键词 Press-fit connector Compliant pin Insertion-withdrawal force Optimization design Neural network model
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Modeling and Analyzing Web Application with Aspect-Oriented Hierarchical Coloured Petri Nets 被引量:1
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作者 Xiaoxing Sun Huiqun Yu +1 位作者 Honghao Liang Nianhua Yang 《China Communications》 SCIE CSCD 2016年第5期89-102,共14页
Aspect-oriented modeling can uncover potential design faults,yet most existing work fails to achieve both separation and composition in a natural and succinct way.This study presents an aspect-oriented modeling and an... Aspect-oriented modeling can uncover potential design faults,yet most existing work fails to achieve both separation and composition in a natural and succinct way.This study presents an aspect-oriented modeling and analysis approach with hierarchical Coloured Petri Nets(HCPN).HCPN has sub-models and well-defined semantics combining a set of submodels.These two characteristics of HCPN are nicely integrated into aspect oriented modeling.Submodels are used to model aspects while the combination mechanism contributes to aspects weaving.Furthermore,the woven aspect oriented HCPN model can be simulated and analyzed by the CPN Tools.A systematic web application case study is conducted.The results show the system original properties are satisfied after weaving aspects and all design flaws are revealed.As such,the approach can support web application design and analysis in an aspect-oriented fashion concisely and effectively. 展开更多
关键词 aspect-oriented modeling hierarchical coloured Petri net CPN Tools ASKCTL
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Context-aware BPEL workflow system using aspect-oriented programming
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作者 Minsuk Kim Donggyu Kuak +1 位作者 Jongsun Choi Jaeyoung Choi 《Journal of Measurement Science and Instrumentation》 CAS 2012年第2期119-122,共4页
Business process execution language(BPEL)is a most recognized standard workflow language.However,it is difficult to be used in the ubiquitous system computing environment because it is difficult to describe the contex... Business process execution language(BPEL)is a most recognized standard workflow language.However,it is difficult to be used in the ubiquitous system computing environment because it is difficult to describe the context information in the selection of the flow through the branch.To solve this problem,we propose a new BPEL workflow system with context-awareness by using aspect-oriented programming(AOP).This system is composed of a BPEL system module and a weaving module using AOP for context-aware.The BPEL system module generates a BPEL workflow program.And the weaving module converts a context-aware mark-up language(CAML)document to the aspect-oriented program that is applied to context-aware code without modification of the existing BPEL document.We also define a new document form that is called CAML,which provides a context-aware that is not available in BPEL.The system can generate a context-aware workflow program.It is developed in a way that inserts context information using AOP to provide context-aware services. 展开更多
关键词 aspect-oriented programming(AOP) business process execution language(BPEL) context-aware workflow
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An Embedded Software Modeling and Process by Using Aspect-Oriented Approach
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作者 Yong-Yi FanJiang Jong-Yih Kuo Shang-Pin Ma 《Journal of Software Engineering and Applications》 2011年第2期106-122,共17页
In recent years, mobile devices have become widespread and refined, and they have offered increased convenience in human life. For these reasons, a variety of embedded systems have been designed. Therefore, improving ... In recent years, mobile devices have become widespread and refined, and they have offered increased convenience in human life. For these reasons, a variety of embedded systems have been designed. Therefore, improving methods for developing of embedded software systematically has become an important issue. Platform-based design is one example of an embedded-system design method that can reduce the design cost via improving a design’s abstraction level. However, platform-based design lacks precise definitions for platforms and design processes. This paper provides an approach that combines the aspects and platform-based design methods for developing embedded software. The approach is built on platform-based design methodology and uses the separating of concerns (SoC) concept to define the aspects and to reduce the crosscutting concerns in embedded system modeling. For aspect issues, we use the extended UML notation with aspects to describe both the static structure and the dynamic structure of the embedded system. We used an example of a digital photo frame system to demonstrate our approach. 展开更多
关键词 Platform-Based Design aspect-oriented UNIFIED Modeling LANGUAGE EMBEDDED SOFTWARE
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Towards Semantic Mutation Testing of Aspect-Oriented Programs
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作者 Abdul Azim Abdul Ghani 《Journal of Software Engineering and Applications》 2013年第10期5-13,共9页
Aspect-oriented programs have received much attention from software testing researchers. Various testing techniques and approaches have been proposed to tackle issues and challenges when testing aspect-oriented progra... Aspect-oriented programs have received much attention from software testing researchers. Various testing techniques and approaches have been proposed to tackle issues and challenges when testing aspect-oriented programs including traditional mutation testing. In traditional mutation testing of aspect-oriented programs, mutants are generated by making small changes to the syntax of the aspect-oriented language. Recently, a new approach known as semantic mutation testing has been proposed. This approach mutates the semantics of the language in which the program is written. The mutants generated misunderstandings of the language which are different classes of faults. Aspect-oriented programming presents itself with different properties that can be further explored with respect to semantic mutation testing. This paper describes various possible scenarios that semantic mutation testing strategy might have particular value in testing aspect-oriented programs. 展开更多
关键词 aspect-oriented PROGRAM TESTING MUTATION TESTING SEMANTIC MUTATION TESTING
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Multi-Objective Optimization of Aluminum Alloy Electric Bus Frame Connectors for Enhanced Durability
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作者 Wenjun Zhou Mingzhi Yang +3 位作者 Qian Peng Yong Peng Kui Wang Qiang Xiao 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第7期735-755,共21页
The widespread adoption of aluminumalloy electric buses,known for their energy efficiency and eco-friendliness,faces a challenge due to the aluminum frame’s susceptibility to deformation compared to steel.This issue ... The widespread adoption of aluminumalloy electric buses,known for their energy efficiency and eco-friendliness,faces a challenge due to the aluminum frame’s susceptibility to deformation compared to steel.This issue is further exacerbated by the stringent requirements imposed by the flammability and explosiveness of batteries,necessitating robust frame protection.Our study aims to optimize the connectors of aluminum alloy bus frames,emphasizing durability,energy efficiency,and safety.This research delves into Multi-Objective Coordinated Optimization(MCO)techniques for lightweight design in aluminum alloy bus body connectors.Our goal is to enhance lightweighting,reinforce energy absorption,and improve deformation resistance in connector components.Three typical aluminum alloy connectors were selected and a design optimization platform was built for their MCO using a variety of software and methods.Firstly,through three-point bending experiments and finite element analysis on three types of connector components,we identified optimized design parameters based on deformation patterns.Then,employing Optimal Latin hypercube design(OLHD),parametric modeling,and neural network approximation,we developed high-precision approximate models for the design parameters of each connector component,targeting energy absorption,mass,and logarithmic strain.Lastly,utilizing the Archive-based Micro Genetic Algorithm(AMGA),Multi-Objective Particle Swarm Optimization(MOPSO),and Non-dominated SortingGenetic Algorithm(NSGA2),we explored optimized design solutions for these joint components.Subsequently,we simulated joint assembly buckling during bus rollover crash scenarios to verify and analyze the optimized solutions in three-point bending simulations.Each joint component showcased a remarkable 30%–40%mass reduction while boosting energy absorption.Our design optimization method exhibits high efficiency and costeffectiveness.Leveraging contemporary automation technology,the design optimization platform developed in this study is poised to facilitate intelligent optimization of lightweight metal components in future applications. 展开更多
关键词 Aluminum connectors three-point bending simulation parametric design model multi-objective collaborative optimization
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Thermal stress simulation analysis of aerospace optical fibers and connectors and related extensions to high-speed railway area
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作者 Feng Zhou Siyuan Yu +3 位作者 Zeren Gao Jie Kan Hao Xu Mengjie Liu 《High-Speed Railway》 2024年第2期122-132,共11页
Aerospace optical cables and fiber-optic connectors have numerous advantages(e.g.,low loss,wide transmission frequency band,large capacity,light weight,and excellent resistance to electromagnetic interference).They ca... Aerospace optical cables and fiber-optic connectors have numerous advantages(e.g.,low loss,wide transmission frequency band,large capacity,light weight,and excellent resistance to electromagnetic interference).They can achieve optical communication interconnections and high-speed bidirectional data transmission between optical terminals and photodetectors in space,ensuring the stability and reliability of data transmission during spacecraft operations in orbit.They have become essential components in high-speed networking and optically interconnected communications for spacecrafts.Thermal stress simulation analysis is important for evaluating the temperature stress concentration phenomenon resulting from temperature fluctuations,temperature gradients,and other factors in aerospace optical cables and connectors under the combined effects of extreme temperatures and vacuum environments.Considering this,advanced optical communication technology has been widely used in high-speed railway communication networks to transmit safe,stable and reliable signals,as high-speed railway optical communication in special areas with extreme climates,such as cold and high-temperature regions,requires high-reliability optical cables and connectors.Therefore,based on the finite element method,comprehensive comparisons were made between the thermal distributions of aerospace optical cables and J599III fiber optic connectors under different conditions,providing a theoretical basis for evaluating the performance of aerospace optical cables and connectors in space environments and meanwhile building a technical foundation for potential optical communication applications in the field of high-speed railways. 展开更多
关键词 Aerospace optical fiber Aerospace optic connector Simulation analysis
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高温电连接器绝缘件失效分析 被引量:2
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作者 钟立强 李齐备 +2 位作者 郭鸿杰 钱萍 陈文华 《工程设计学报》 北大核心 2025年第3期367-372,共6页
针对高温环境下绝缘材料易老化裂解乃至碳化,导致高温电连接器绝缘性能下降而不能满足型号装备工作要求的问题,以某型号装备用J58型高温电连接器为研究对象,分析并验证了其聚酰亚胺(polyimide, PI)绝缘件的失效机理。同时,通过高温劣化... 针对高温环境下绝缘材料易老化裂解乃至碳化,导致高温电连接器绝缘性能下降而不能满足型号装备工作要求的问题,以某型号装备用J58型高温电连接器为研究对象,分析并验证了其聚酰亚胺(polyimide, PI)绝缘件的失效机理。同时,通过高温劣化实验研究了其绝缘性能的变化情况。实验结果表明:PI绝缘件在450℃下持续工作30 min后出现了碳化趋势,其绝缘电阻显著下降,但大于5 GΩ,仍可满足某型高超导弹的工作要求。研究结果为高温电连接器的可靠性设计、选用及后期维护决策提供了依据,并有助于提升高超导弹等型号装备的可靠性。 展开更多
关键词 高温电连接器 绝缘性能 失效机理
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The Design of Multi-Connector IoT Central Gateway Based on Raspberry Pi and Docker
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作者 Jie Wang 《Journal of Electronic Research and Application》 2024年第5期66-71,共6页
With the vigorous development of Internet of Things(IoT)technology,the demand for communication and data exchange between different types of IoT devices is increasing day by day.To solve the problems of diversity and ... With the vigorous development of Internet of Things(IoT)technology,the demand for communication and data exchange between different types of IoT devices is increasing day by day.To solve the problems of diversity and complexity of communication protocols between devices,this paper proposes a design scheme of a multi-connector IoT central gateway based on Raspberry Pi and Docker.Through the research and application of related technologies,by integrating multiple communication interfaces and utilizing containerization technology,an efficient,flexible,and scalable IoT central gateway has been realized,which can support the connection and data interaction of multiple communication protocols and provide strong support for the stable operation and development of the IoT system. 展开更多
关键词 Internet of Things Raspberry Pi DOCKER connector Central Gateway
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耐候高强螺栓连接锈后抗滑移性能及有限元模拟方法 被引量:1
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作者 王涛 袁阳光 +3 位作者 许家溶 袁卓亚 翟晓亮 杨飞 《中国公路学报》 北大核心 2025年第5期101-111,共11页
为研究耐候高强螺栓连接锈蚀后的抗滑移性能并建立其有限元模拟方法,首先针对Q345qDNH钢材开展锈后拉伸性能试验,并校准其拉伸本构关系;其次,设计Q345qDNH钢材四栓高强螺栓连接件,开展拉伸性能测试,分析滑移荷载、局部滑移行为特征及抗... 为研究耐候高强螺栓连接锈蚀后的抗滑移性能并建立其有限元模拟方法,首先针对Q345qDNH钢材开展锈后拉伸性能试验,并校准其拉伸本构关系;其次,设计Q345qDNH钢材四栓高强螺栓连接件,开展拉伸性能测试,分析滑移荷载、局部滑移行为特征及抗滑移系数;最后,基于所校准的材料本构关系,建立了连接件拉伸性能的有限元模拟方法,并验证其适用性。研究结果发现:锈蚀程度较低时,Q345qDNH钢材抗变形能力变化较小,抗变形能力随失重率增大而减小;稳定锈层形成时,Q345qDNH钢材的上屈服强度、平均抗拉强度较初始状态分别下降4.6%、4.5%,材料未锈蚀时,断后伸长率及最大力塑性延伸率分别为44.1%、14.4%,形成稳定锈层时,2个指标分别下降35.1%、15.1%;Q345qDNH钢材四栓连接件的局部滑移行为具有随机性,通常在第1排、第3排螺栓处产生相对滑移,连接件无锈蚀时,滑移位置多伴随2个摩擦面同时滑移,连接件锈蚀后,滑移位置可能为2个摩擦面同时滑移或1个摩擦面滑移;Q345qDNH钢材高强螺栓连接件在无锈蚀状态的抗滑移系数约为0.5503,暴露部位稳定锈层形成时约为0.5291,但数值水平有进一步的增长空间,采用现行规范建议值进行相关设计计算时,能够保证足够的安全冗余;所建立的有限元模拟方法得到的滑移荷载与实测值的误差为11.32%,能够支撑后续大批量的数值模拟工作。 展开更多
关键词 桥梁工程 耐候钢高强螺栓连接件 拉伸试验 抗滑移性能 有限元模拟
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摩擦型自复位梁柱节点的滞回与损伤性能研究 被引量:1
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作者 卢啸 徐航 张雪敏 《工程力学》 北大核心 2025年第8期187-196,共10页
为减小传统钢筋混凝土节点(reinforced concrete joint,RCJ)的残余变形和塑性损伤,便于震后快速修复,提出了一种新型的摩擦型自复位现浇梁柱节点(self-centering frictional cast-in-situ beam-column joint,SCFJ),通过在梁端两个削弱... 为减小传统钢筋混凝土节点(reinforced concrete joint,RCJ)的残余变形和塑性损伤,便于震后快速修复,提出了一种新型的摩擦型自复位现浇梁柱节点(self-centering frictional cast-in-situ beam-column joint,SCFJ),通过在梁端两个削弱区域增设兼具自复位能力和耗能能力的摩擦型自复位连接件(friction self-centering connectors,FC),从而减小结构的残余变形,同时将损伤集中在削弱梁段。该文对一SCFJ试件和一RCJ试件进行了低周往复加载试验,对两者的滞回性能、复位能力、耗能能力、损伤演化进行对比分析。并建立了SCFJ的精细有限元模型,对其滞回性能进行模拟。研究结果表明:SCFJ的损伤主要集中在削弱梁段,实现了损伤可控,SCFJ的混凝土剥落和纵筋屈服均晚于RCJ,损伤程度明显降低;SCFJ的承载力及耗能能力与RCJ相比略低,但残余位移明显减小,在层间位移角为2.5%时,残余位移仍小于0.5%,仅为RCJ残余位移的32%,具有良好的自复位能力。 展开更多
关键词 自复位节点 摩擦型自复位连接件 低周往复荷载试验 抗震性能 损伤演化
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基于RANSAC改进算法的连接器位姿检测
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作者 张硕 史玲玲 +2 位作者 王威威 金鑫 李忠新 《电子测量技术》 北大核心 2025年第12期137-145,共9页
连接器的多针对接装配过程中,如果不能准确获得零件的位置和姿态,将很可能导致连接器对接任务失败,甚至造成插针弯曲或零件结构损坏。然而受图像噪声、孔内加工痕迹、孔深导致失焦以及孔壁阴影等因素的干扰,在进行孔的检测工作时难以精... 连接器的多针对接装配过程中,如果不能准确获得零件的位置和姿态,将很可能导致连接器对接任务失败,甚至造成插针弯曲或零件结构损坏。然而受图像噪声、孔内加工痕迹、孔深导致失焦以及孔壁阴影等因素的干扰,在进行孔的检测工作时难以精准地获取完整精确的圆形轮廓,从而对连接器位姿检测精度产生较为显著的负面影响。针对上述问题,本文提出了一种基于RANSAC的圆拟合改进算法。首先,通过霍夫梯度法进行粗定位,然后通过RANSAC算法获得待拟合圆的内点集;最后,提出了依据邻域内点相对数量确定权重的WLS,重新对内点集进行圆拟合,进而计算得到连接器精确位姿。本文还进行了精度测试实验,测得姿态平均误差为0.051°,位置平均误差为0.567 pixel,并与其他常见算法进行对比,最终验证本文算法具有较高的精确度与稳定性,检测效果优于其他算法。 展开更多
关键词 连接器 圆拟合 随机抽样一致性 最小二乘法
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双向荷载下组合剪力键的剪切机理及抗剪强度计算模型
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作者 马亚飞 胡涛 +3 位作者 章拔超 周彪 王磊 张建仁 《土木与环境工程学报(中英文)》 北大核心 2025年第3期171-179,共9页
为研究双向荷载作用下组合剪力键的剪切性能,建立组合剪力键有限元模型,并结合试验进行验证;对比双向和单向推出荷载作用下组合剪力键的破坏形态,研究双向荷载与组合剪力键抗剪强度比的关系,量化混凝土强度和贯穿钢筋直径对组合剪力键... 为研究双向荷载作用下组合剪力键的剪切性能,建立组合剪力键有限元模型,并结合试验进行验证;对比双向和单向推出荷载作用下组合剪力键的破坏形态,研究双向荷载与组合剪力键抗剪强度比的关系,量化混凝土强度和贯穿钢筋直径对组合剪力键抗剪强度的影响;揭示组合剪力键的剪切破坏机理,通过多变量回归分析,建立双向荷载作用下组合剪力键抗剪强度计算模型。结果表明:侧压荷载有效抑制了混凝土横向膨胀,混凝土板出现一条纵向主裂缝和少量横向微裂纹,单向推出荷载作用下,组合剪力键因混凝土板劈裂裂缝贯通而失效;侧压荷载能增加组合剪力键抗剪强度,但混凝土强度较高且贯穿钢筋直径较大时,双向荷载效应较小,抗剪强度比仅为1.05;双向荷载作用下,抗剪强度随混凝土强度和贯穿钢筋直径的增加而显著增加。 展开更多
关键词 钢-混组合梁 剪力键 双向荷载 剪切机理 荷载-滑移
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某典型低温连接器箭地接口解锁部位防结冰研究
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作者 张振华 李文翰 +2 位作者 贺建华 常新 王宇亮 《导弹与航天运载技术(中英文)》 北大核心 2025年第2期55-59,共5页
低温连接器作为运载火箭箭地接口关键设备,用于低温推进剂的加注、泄出及排气,射前脱落或者零秒脱落。受海南发射场高温高湿环境影响,长时间加注后箭地接口的低温表面更易结霜、结冰,阻碍分离机构动作,增加了连接器脱落阻力,历史任务中... 低温连接器作为运载火箭箭地接口关键设备,用于低温推进剂的加注、泄出及排气,射前脱落或者零秒脱落。受海南发射场高温高湿环境影响,长时间加注后箭地接口的低温表面更易结霜、结冰,阻碍分离机构动作,增加了连接器脱落阻力,历史任务中曾出现影响发射流程的质量问题。针对箭上接口提出改进方案,通过热设计优化减少或避免箭地接口解锁部位结冰,降低解锁阻力。 展开更多
关键词 低温连接器 箭上接口 运载火箭 脱落 结冰
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盾构隧道快速连接件管片接缝平底密封垫防水性能 被引量:1
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作者 丁文其 李睿佳 +3 位作者 乔亚飞 吴昱东 于勇 黄继辉 《长安大学学报(自然科学版)》 北大核心 2025年第4期53-67,共15页
为探索新型平底密封垫的防水性能,对三元乙丙橡胶平底密封垫进行了数值计算,使用万能试验机进行了压缩试验,制作了混凝土管片试块,进行了足尺防水试验,设计并进行了不同张开量下三元乙丙橡胶密封垫压缩热氧老化试验,并使用阿伦尼乌斯方... 为探索新型平底密封垫的防水性能,对三元乙丙橡胶平底密封垫进行了数值计算,使用万能试验机进行了压缩试验,制作了混凝土管片试块,进行了足尺防水试验,设计并进行了不同张开量下三元乙丙橡胶密封垫压缩热氧老化试验,并使用阿伦尼乌斯方程预测了密封垫的长期防水性能。研究结果表明:错台分别为0、3、5 mm时密封垫拼装所需的闭合压力分别为24.85、21.87、24.59 kN/m,平底面设计有效减小了密封垫闭合所需的拼装力;不同错台下的闭合压力接近,说明取消柱脚结构减小了错台对密封垫压缩性能的影响;在管片张开3 mm与错台5 mm的最不利工况下,平底密封垫的防水能力达到了0.8 MPa,满足短期设计防水要求的0.7 MPa;混凝土试具试验得到的极限防水能力小于钢制试具,混凝土的粗糙表面降低了密封垫的防水能力,平底密封垫与混凝土之间的界面可能成为潜在的防水薄弱环节;将密封垫底面纳入渗水路径考虑后,大部分工况下试验与数值模拟得到的耐水压差在80 kPa以内,数值模拟方法可靠;与传统带柱脚结构的密封垫不同,取消柱脚结构后底面不再产生应力集中,其防水性能可能小于密封垫顶面;平底密封垫在管片张开0、3 mm时,常温下老化系数分别为0.45和0.72,老化性能优于传统密封垫与圆柱体试件;密封垫受到的压力越大,性能衰减越快,且对温度变化更敏感。 展开更多
关键词 盾构隧道 快速连接件 三元乙丙橡胶 平底密封垫 接缝防水性能 热氧老化 长期性能预测
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搭接长度等对Ⅱ型APC接头拉伸性能的影响
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作者 余琼 敖晟瑞 +4 位作者 唐子鸣 郭霖 谢青海 张志 陈振海 《哈尔滨工业大学学报》 EI CAS 北大核心 2025年第1期128-139,共12页
为研究搭接长度和钢筋直径对Ⅱ型APC接头力学性能的影响,对63个该接头进行单向拉伸试验,分析了接头破坏模式、极限承载力、延性和黏结应力等。结果表明:钢筋直径相同时,随搭接长度增加,平均黏结应力降低,试件强度、延性、最大力总伸长... 为研究搭接长度和钢筋直径对Ⅱ型APC接头力学性能的影响,对63个该接头进行单向拉伸试验,分析了接头破坏模式、极限承载力、延性和黏结应力等。结果表明:钢筋直径相同时,随搭接长度增加,平均黏结应力降低,试件强度、延性、最大力总伸长率明显提高,残余变形整体呈下降趋势;钢筋拉断破坏试件强度、延性、最大力总伸长率和残余变形满足规范要求;加载过程中,套筒中部截面短边纵向和长边环向始终受拉;极限荷载下,随搭接长度增加,套筒中部截面短边侧环向压应变先转变为拉应变再向压应变发展,长边侧纵向压应变转变为拉应变;相对搭接长度相同时,极限承载力随钢筋直径增加而提高;提出的极限黏结强度及临界搭接长度计算公式与试验值吻合较好,可为实际工程应用提供参考。单拉工况下,钢筋直径不大于18 mm时,建议接头搭接长度大于12 d。 展开更多
关键词 Ⅱ型APC接头 拉伸性能 搭接长度 黏结强度
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汽车软管接头复合弯管抽芯机构模具设计
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作者 郑子军 刘晓彬 +3 位作者 张涛 陈燕红 李亚峰 肖国华 《塑料工业》 北大核心 2025年第6期71-77,共7页
针对汽车软管接头塑件的弯管特征成型难点,设计了一种复合弯管抽芯机构和两板冷流道模具用于塑件的自动化注塑生产。该塑件的弯管包含2个分段,一段为直管,一段为90°弯管。直管分段需要针对内、外壁的脱模设计抽芯机构,弯管段需要... 针对汽车软管接头塑件的弯管特征成型难点,设计了一种复合弯管抽芯机构和两板冷流道模具用于塑件的自动化注塑生产。该塑件的弯管包含2个分段,一段为直管,一段为90°弯管。直管分段需要针对内、外壁的脱模设计抽芯机构,弯管段需要对弯管内壁设计旋转抽芯机构。因而限于塑件弯管外壁周边局部特征的特点,针对直管段设计了一个内、外壁同步抽芯子机构,外壁的局部特征采用一个下降成型块成型,并由内壁的抽芯滑块驱动而实施二次抽芯动作。针对弯管段则设计一个油缸驱动扇形齿轮抽芯的旋转抽芯子机构,机构的扇形齿轮直接安装在型芯镶件的圆弧槽内,并由油缸驱动齿条进行驱动。闭模时扇形齿轮由第一个子机构的内壁抽芯滑块锁紧。复合机构在设计空间狭窄的条件下,巧妙地解决了塑件弯管的自动脱模难题。模具中,基于分区脱模方法还设计了2个斜导柱滑块用于塑件一个直管和一个安装板局部特征的成型与脱模。模具结构布置合理,机构结构设计恰当,能有效降低模具制造成本,模具中复合机构的设计能为同类塑件的模具结构设计提供有益参考。 展开更多
关键词 注塑 软管接头 复合机构 插锁机构 模具设计 弯管抽芯
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基于两相流理论的水下法兰连接器透镜垫强度及寿命
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作者 秦建国 孙志 +3 位作者 弓海霞 崔朝霞 巩勇智 郭思佳 《机械设计》 北大核心 2025年第S1期55-60,共6页
在水下油气生产系统中,针对水下采油井口的突然开启和关闭、油气输送的非连续性造成管道内油气输送速度剧烈变化,从而在管道中形成压力波动,对水下法兰连接器透镜垫造成压力冲击的问题,通过分层流模型确定气液参数,借助Fluent中的VOF模... 在水下油气生产系统中,针对水下采油井口的突然开启和关闭、油气输送的非连续性造成管道内油气输送速度剧烈变化,从而在管道中形成压力波动,对水下法兰连接器透镜垫造成压力冲击的问题,通过分层流模型确定气液参数,借助Fluent中的VOF模型对水下法兰连接器部分内的气液两相流介质进行模拟,选用RNG k-ε湍流模型对水下法兰连接器部分油气流动参数进行分析计算及模拟求解,分析了不同输送速度连接器部分内油气对外压力的分布。结果显示,最大压力冲击的增量与油气输送速度平方的增量近似成正比关系,在考虑油气输送速度对水下法兰连接器透镜垫内壁最大压力冲击后,透镜垫最大等效应力增大9.36%,疲劳寿命下降51.33%。 展开更多
关键词 水下法兰连接器 气液两相流 VOF模型 流体压力 疲劳寿命
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长贮环境下高频电连接器接触性能退化规律的研究
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作者 陈文华 杨定 +2 位作者 陈哲文 方英春 钟立强 《机械工程学报》 北大核心 2025年第14期344-351,共8页
高频电连接器是型号系统中用于实现高频信号传输的基础元件,其接触性能的退化会造成信号衰减和反射等问题。以J599型高频电连接器为研究对象,分析接触件表面接触状态,建立插入损耗计算方法。考虑温度的影响,分析高频电连接器在贮存环境... 高频电连接器是型号系统中用于实现高频信号传输的基础元件,其接触性能的退化会造成信号衰减和反射等问题。以J599型高频电连接器为研究对象,分析接触件表面接触状态,建立插入损耗计算方法。考虑温度的影响,分析高频电连接器在贮存环境条件下的接触件表面氧化腐蚀物的增长规律,建立接触对的插入损耗退化轨迹模型。以温度为加速应力开展J599型高频电连接器的加速退化试验,结果表明,提高温度可加快接触性能退化,不同应力水平下的接触退化趋势与轨迹模型预测结果一致。建立基于阿伦尼斯模型的双加速方程,外推得到正常贮存环境下的接触性能退化趋势,可用于指导高频电连接器的可靠性设计、评估和使用维护。 展开更多
关键词 高频电连接器 贮存环境 性能退化模型 插入损耗
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电连接器用G100硅橡胶绝缘件贮存可靠性建模与验证
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作者 钱萍 施佳煜 +2 位作者 陈文华 杨帆 王友维 《工程设计学报》 北大核心 2025年第4期514-522,共9页
针对电连接器用G100硅橡胶绝缘件在长期贮存条件下的可靠性建模问题,从微观层面分析并揭示了其绝缘电阻下降的主要原因是环境温度和湿度引起了材料基体大分子基团发生氧化和水解反应;基于分子动力学和质量作用定律,分析了在温度和湿度... 针对电连接器用G100硅橡胶绝缘件在长期贮存条件下的可靠性建模问题,从微观层面分析并揭示了其绝缘电阻下降的主要原因是环境温度和湿度引起了材料基体大分子基团发生氧化和水解反应;基于分子动力学和质量作用定律,分析了在温度和湿度影响下G100硅橡胶载流子浓度的变化,建立了G100硅橡胶失效物理模型;结合中心极限定理,构建了G100硅橡胶绝缘件贮存可靠性模型;利用A-D(Anderson-Darling)检验法和拟合优度检验法,结合扫描电镜和傅里叶变换红外光谱仪,验证了所构建模型的正确性和合理性。研究结果为电连接器用G100硅橡胶在长贮条件下的绝缘可靠性评估提供了理论基础。 展开更多
关键词 电连接器绝缘件 G100硅橡胶 失效物理模型 可靠性评估
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