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Chinese Journal of Aeronautics 2018年第1期31卷 169-177页

作者： junhui zhang Qun CHAO Bing XU State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang University

Electro-hydrostatic actuator （EHA） pumps are usually characterized as high speed and small displacement. The tilting inertia moment on the cylinder block produced by the inertia forces of piston/slipper assemblies cannot be ignored when analyzing the cylinder block balance. A large tilting inertia moment will make the cylinder block tilt away from the valve plate, resulting in severe wear and significantly increased leakage. This paper presents an analytical expression for the tilting inertia moment on the cylinder block by means of vector analysis. In addition, a high-speed test rig was built up, and experiments on an EHA pump prototype were carried out at high speeds of up to 10,000 r/min. The predicted nature of the cylinder block tilt at high speeds corresponds closely to the witness marks on the dismantled EHA pump prototype, It is suggested that more attention should be given to the tilting inertia moment acting on the cylinder block of an EHA pump since both wear and leakage flow between the cylinder block and the valve plate are very much dependent on this tilting moment.

关键词： Aircraft pump Cylinder block High speed Inertia moment Leakage Wear

群体智能算法在路面参数反分析中的适用性及优选策略

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土木与环境工程学报（中英文） 2024年第5期46卷 191-203页

作者：杨森顺邓尚瑛范海山张军辉广西交通设计集团有限公司南宁530029 长沙理工大学交通运输工程学院长沙410114

随着群体智能算法在路面参数反演中的成功应用,复杂多元非线性优化难题得以解决,但算法的选择仍然是路面参数反分析问题中亟待解决的难题。针对路面参数反分析中模型复杂、反演参数众多、绝大多数运算时间消耗在正算程序上等问题,选择8... 详细信息

随着群体智能算法在路面参数反演中的成功应用,复杂多元非线性优化难题得以解决,但算法的选择仍然是路面参数反分析问题中亟待解决的难题。针对路面参数反分析中模型复杂、反演参数众多、绝大多数运算时间消耗在正算程序上等问题,选择8种常见的群体智能算法,开展限定正算调用次数下算法性能相关研究,并以考虑材料横观各向同性以及层间接触状态的路面结构参数反演问题为例,对群体智能算法进行实际测试。结果表明:不同算法各具特点,其中,粒子群算法、遗传算法、头脑风暴算法、人工蜂群算法以及烟花算法在多峰问题上具有较好的适用性;萤火虫算法在解决最优解附近存在平缓区域的问题时具有较快的收敛速度;对于遗传算法,实数编码方式后期收敛速度较二进制编码方式有所提高,但对于多峰问题的搜索能力有所下降;鱼群算法、混合蛙跳算法仅有在较大正算调用次数下才有较好的寻优能力。对于路面参数反演问题,从弯沉曲线匹配上看,粒子群算法、遗传算法、头脑风暴算法以及萤火虫算法均有较好的反演结果;而从相关系数上看,头脑风暴算法具有最佳反演结果。

关键词：路基路面参数反演群体智能算法头脑风暴算法遗传算法粒子群算法

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Investigation on the Radial Micro-motion about Piston of Axial Piston Pump

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Chinese Journal of Mechanical Engineering 2013年第2期26卷 325-333页

作者： XU Bing zhang junhui YANG Huayong zhang Bin State Key Laboratory of Fluid Power Transmission and Control Zhejiang University

The limit working parameters and service life of axial piston pump are determined by the carrying ability and lubrication characteristic of its key friction pairs. Therefore, the design and optimization of the key friction pairs are always a key and difficult problem in the research on axial piston pump. In the traditional research on piston/cylinder pair, the assembly relationship of piston and cylinder bore is simplified into ideal cylindrical pair, which can not be used to analyze the influences of radial micro-motion of piston on the distribution characteristics of oil-film thickness and pressure in details. In this paper, based on the lubrication theory of the oil film, a numerical simulation model is built, taking the influences of roughness, elastic deformation of piston and pressure-viscosity effect into consideration. With the simulation model, the dynamic characteristics of the radial micro-motion and pressure distribution are analyzed, and the relationships between radial micro-motion and carrying ability, lubrication condition, and abrasion are discussed. Furthermore, a model pump for pressure distribution measurement of oil film between piston and cylinder bore is designed. The comparison of simulation and experimental results of pressure distribution shows that the simulation model has high accuracy. The experiment and simulation results demonstrate that the pressure distribution has peak values that are much higher than the boundary pressure in the piston chamber due to the radial micro-motion, and the abrasion of piston takes place mainly on the hand close to piston ball. In addition, improvement of manufacturing roundness and straightness of piston and cylinder bore is helpful to improve the carrying ability of piston/cylinder pair. The proposed research provides references for designing piston/cylinder pair, and helps to prolong the service life of axial piston pump.

关键词： axial piston pump piston/cylinder pair micro motion carrying ability

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面向数字孪生工程的水利知识图谱构建及应用

人民黄河 2024年第4期46卷 121-124,130页

作者：张军珲黄希扬桂明宇昝红英张坤丽黄河勘测规划设计研究院有限公司河南郑州450003 云河(河南)信息科技有限公司河南郑州450003 郑州大学计算机与人工智能学院河南郑州450001

构建水利领域的知识图谱可为数字孪生水利工程建设提供结构化的知识支持。基于黄河小浪底、万家寨水利枢纽预报调度、工程安全、业务规则数据,使用实体识别和关系抽取模型构建面向数字孪生工程的水利知识图谱(KG4DT),并对图谱进行可视... 详细信息

构建水利领域的知识图谱可为数字孪生水利工程建设提供结构化的知识支持。基于黄河小浪底、万家寨水利枢纽预报调度、工程安全、业务规则数据,使用实体识别和关系抽取模型构建面向数字孪生工程的水利知识图谱(KG4DT),并对图谱进行可视化展示。以水利枢纽为核心确定实体分类体系及关系分类体系,构建KG4DT的模式层。使用二次开发的标注平台对非结构化文本进行半自动标注和人工校对,构建KG4DT的数据层。以黄河小浪底和万家寨水利枢纽防洪、减淤、供水、发电业务为主线,结合AC自动机等技术设计知识检索、预案自动生成应用,可为工程运行提供智能决策支撑。

关键词：水利知识图谱数字孪生知识描述体系应用

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岩石破坏前兆的k-均值聚类识别方法

矿业研究与开发 2024年第1期44卷 112-117页

作者：李国墙张军徽杨金诺宋义敏北方工业大学土木工程学院北京100144

为研究岩石在外力扰动下发生突发性破坏时,与岩石破坏前兆密切相关的声发射信号,基于k-均值聚类方法的特征,开展了红砂岩单轴压缩声发射试验,以声发射信号的能量、幅度、上升时间、持续时间和振铃计数5个参数作为特征向量,进行k-均值聚... 详细信息

为研究岩石在外力扰动下发生突发性破坏时,与岩石破坏前兆密切相关的声发射信号,基于k-均值聚类方法的特征,开展了红砂岩单轴压缩声发射试验,以声发射信号的能量、幅度、上升时间、持续时间和振铃计数5个参数作为特征向量,进行k-均值聚类分析,获得了3种不同类型的声发射信号,并开展了时序演化分析。结果表明,第一类和第二类声发射信号自弹性阶段开始便持续密集出现,直至试验结束,无明显演化异常的阶段性变化;第三类信号在弹性变形阶段零星出现,在变形局部化阶段突变为持续密集出现,有明显的演化异常,与岩石的破坏机理相符,且异常时间点与散斑云图突变时间点相同,该类信号还具有能量占比大、信号数量占比小的特征,能够反映岩石破坏前兆信息,适用于岩石破坏预警。

关键词：聚类分析 k-均值聚类岩石破坏前兆声发射时序演化

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不良孕产史与胎儿染色体异常的相关性分析

内蒙古医学杂志 2024年第3期56卷 276-280页

作者：薛丹丹张俊绘内蒙古科技大学包头医学院内蒙古包头014040 内蒙古自治区妇幼保健院产科呼和浩特010020

目的分析不良孕产史与胎儿染色体异常的相关性。方法选取2021年1月至2022年12月因不良孕产史就诊于内蒙古自治区妇幼保健院产前诊断中心行羊水穿刺的孕妇209例,观察不良孕产史合并夫妻染色体异常以及高龄时的染色体异常核型发生频率、... 详细信息

目的分析不良孕产史与胎儿染色体异常的相关性。方法选取2021年1月至2022年12月因不良孕产史就诊于内蒙古自治区妇幼保健院产前诊断中心行羊水穿刺的孕妇209例,观察不良孕产史合并夫妻染色体异常以及高龄时的染色体异常核型发生频率、分布和统计特征。结果仅以不良孕产史为指征的孕妇中染色体核型分析结果异常检出率为0.96%,检出结果均为染色体结构异常;多项指征的异常核型发生率均显著高于单项指征,检出率差异具有统计学意义(P<0.05);不良孕产史合并夫妻染色体异常的染色体核型结果异常检出率为3.83%(8/209),占总染色体核型异常的26.67%(8/30),检出染色体核型均为结构异常,当不良孕产史合并夫妻一方染色体异常时可存活的子代染色体1/2的概率会与其父或其母异常的染色体核型相同;不良孕产合并高龄的染色体核型结果异常检出率为5.74%(12/209),占总染色体核型异常的40.00%(12/30),检出染色体核型异常以数目异常为主(8/12),其中又以21-三体占比最高(5/8)。说明不良孕产史合并高龄的孕妇中胎儿染色体异常的主要类型依旧是21-三体综合征。结论具有不良孕产史的孕妇在产前行染色体核型分析可有效预防缺陷儿的出生。

关键词：不良孕产史染色体异常核型分析

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隐私计算环境下的公共数据授权运营法治路径

网络空间安全 2024年第3期15卷 17-21页

作者：韩文蕾张军辉西北工业大学

[目的/意义]应用隐私计算技术，可以实现数据使用过程的“可用不可见”，有效地保障公共数据授权运营的安全，同时也带来运营各主体的身份转换和权利义务的重新配置，因此需要构建相应的法治解决方案。[方法/过程]阐明隐私计算保障数据... 详细信息

[目的/意义]应用隐私计算技术，可以实现数据使用过程的“可用不可见”，有效地保障公共数据授权运营的安全，同时也带来运营各主体的身份转换和权利义务的重新配置，因此需要构建相应的法治解决方案。[方法/过程]阐明隐私计算保障数据安全的机理以及公共数据授权运营过程，分析在主体、行为、对象三个层面的法治新要求。[结果/结论]提出包括设定“可用不可见”的适用范围、规范授权运营平台的定位和数据加工行为，构建规范数据产品和服务制度等方面的法治应对方案。

关键词：隐私计算数据安全公共数据授权运营法治数据安全治理

Influence of Piston Number on Churning Losses in Axial Piston Pumps

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Chinese Journal of Mechanical Engineering 2022年第5期35卷 194-207页

作者： Ying Li Xing Chen Hao Luo junhui zhang Jin zhang School of Mechanical Engineering Yanshan UniversityQinhuangdao 066004China State Key Laboratory of Fluid Power Transmission and Control Zhejiang UniversityHangzhou 310027China

Raising the rotational speed of an axial piston pump is useful for improving its power density;however,the churning losses of the piston increase significantly with increasing speed,and this reduces the performance and efficiency of the axial piston ***,there has been some research on the churning losses of pistons;however,it has rarely been analyzed from the perspective of the piston *** improve the performance and efficiency of the axial piston pump,a computational fluid dynamics(CFD)simulation model of the churning loss was established,and the effect of piston number on the churning loss was studied in *** simulation analysis results revealed that the churning losses initially increased as the number of pistons increased;however,when the number of pistons increased from six to nine,the torque of the churning losses decreased because of the hydrodynamic shadowing *** addition,in the analysis of cavitation results,it was determined that the cavitation area of the axial piston pump was mainly concentrated around the piston,and the cavitation became increasingly severe as the speed *** comparing the simulation results with and without the cavitation model,it was observed that the cavitation phenomenon is beneficial for the reduction of churning *** this study,a piston churning loss test rig that can eliminate other friction losses was established to verify the accuracy of the simulation results.A comparative analysis indicated that the simulation results were consistent with the actual *** addition,this study also conducted a simulation study on seven and nine piston pumps with the same *** simulation results revealed that churning losses of the seven pistons were generally greater than those of the nine pistons under the same *** addition,regarding the same piston number and displacement,reducing the pitch circle radius of piston bores is effective in reducing the churning *** resea

关键词： Axial piston pumps Churning losses Pistons CFD simulations Experimental study

Investigation on structural optimization of anti-overturning slipper of axial piston pump

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Science China(Technological Sciences) 2012年第11期55卷 3010-3018页

作者： XU Bing zhang junhui YANG HuaYong State Key Laboratory of Fluid Power Transmission and Control Zhejiang UniversityHangzhou 310027China

Improving the carrying ability of oil film between slipper and swash plate and reducing the partial abrasion of slipper are important to improve the service life and reliability of axial piston *** this paper,a numerical simulation model was developed for slipper/swash-plate friction pair based on the elastohydrodynamic *** dynamic micro-motion and pressure distribution of slipper were analyzed and it was pointed out that the tilt of slipper was the main reason for its partial *** simulations about the slippers with different slopes on the outer edge of the sealing belt showed that the partial abrasion could reduce the carrying ability and increase the leakage of the slipper/swash-plate *** proper slope on the inner edge helped to improve the carrying ability and reduce the leakage of *** experimental tests were in accord with the simulation results to a great extent,showing that the simulation model had a high accuracy and could be applied to the design and optimization of slipper,and that the slipper with optimal inner slope provided an encouraging method to improve the efficiency and reliability of axial piston pump.

关键词： axial piston pump slipper anti-overturning partial abrasion

制造企业智能化转型绩效影响因素的组态效应——基于“动机-能力-机会”(AMO)理论分析框架

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科技管理研究 2024年第10期44卷 143-152页

作者：李潭张均辉陈伟哈尔滨工程大学经济管理学院黑龙江哈尔滨150001 广东海洋大学管理学院广东湛江524088 黑龙江东方学院管理学院黑龙江哈尔滨150076

制造企业智能化转型是多种要素协同作用的结果,而如何提升转型绩效是当前中国制造企业面临的主要难题。但学界针对此议题的深入研究尚较为缺乏。对此,首先对制造企业智能化转型概念作出定义并分析其内涵要素;其次,鉴于组织、团队或个体... 详细信息

制造企业智能化转型是多种要素协同作用的结果,而如何提升转型绩效是当前中国制造企业面临的主要难题。但学界针对此议题的深入研究尚较为缺乏。对此,首先对制造企业智能化转型概念作出定义并分析其内涵要素;其次,鉴于组织、团队或个体的绩效水平会受到其能力(ability)、动机(motivation)和机会(opportunity)等多方面因素的影响,基于“动机-能力-机会”(AMO)理论框架构建制造企业智能化转型绩效影响因素的组态模型;最后,采用面向全国制造企业的103份有效调查问卷数据,并结合典型案例,运用模糊集定性比较分析方法(fsQCA)分析企业转型能力(企业动态能力、企业知识禀赋)、转型动机(内在转型需求、外部竞争压力)以及转型机会(政府政策支持、数字基础设施)对于样本企业智能化转型绩效的组态效应。结果表明:能力、动机和机会均无法单独构成制造企业高智能化转型绩效的必要条件;存在8种会导致企业高智能化转型绩效的条件组态并可归纳为能力主导机会支持型、动机主导能力支持型、动机主导机会支持型、机会主导能力支持型和能力、动机、机会兼备型五大组态类型;有1种条件组态会导致企业非高智能化转型绩效,可归纳为能力、动机、机会兼不具备型。由此得到启示:制造企业在向智能制造转型升级的过程中须重视对自身能力、动机和机会三者情况进行综合性考量,结合实际选择合理的转型升级路径。

关键词：制造企业智能化转型转型绩效要素协同 “能力-动机-机会”(AMO)理论模糊集定性比较分析方法(fsQCA) 组态分析智能制造