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机器人在骨科手术中应用的可靠性与提升空间 预览
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作者 曹旭含 白子兴 +2 位作者 孙承颐 李晏乐 孙卫东 《中国组织工程研究》 CAS 北大核心 2020年第9期1416-1421,共6页
背景:骨科手术机器人是一种集医学、电子信息学、机械物理学等多学科、多领域为一体的新型医疗器械,是当代医学信息化、程控化、智能化的一个重要发展方向,在骨科手术中有着安全可靠性与广泛的应用前景。目的:探讨机器人在骨科手术中的... 背景:骨科手术机器人是一种集医学、电子信息学、机械物理学等多学科、多领域为一体的新型医疗器械,是当代医学信息化、程控化、智能化的一个重要发展方向,在骨科手术中有着安全可靠性与广泛的应用前景。目的:探讨机器人在骨科手术中的应用可靠性及提升空间。方法:以中文检索词“机器人,骨科,手术,精准度”和英文检索词“Robot,Orthopedics,Surgery,Accuracy”分别检索CNKI数据库、维普数据库、万方数据库和PubMed数据库自建库至2049年6月的文献。根据入选标准保留49篇文献,对手术机器人应用于骨科手术的关键问题进行综述。结果与结论:①目前对骨科手术机器人的研究较多,方法较成熟,但是国内手术机器人的研究相对于发达国家还处于初级阶段;②骨科手术机器人技术正朝着人机智能化、图像精细化、形态精微化、手术无创化、远程可控流畅化等方向发展;③推动自主研发骨科手术机器人产品、全方位制定行业规范和临床标准,将是中国智能医疗器械及设备发展的重要导向。 展开更多
关键词 机器人 骨科 手术 人工智能 精准度 提升空间 可靠性 临床应用
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考虑性能依赖的元动作单元多态可靠性分析 预览
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作者 周伟 朱晓 +2 位作者 冉琰 杨欣 柯磊 《哈尔滨工业大学学报》 EI CAS CSCD 北大核心 2020年第1期62-68,共7页
为研究单元之间相互作用所引起的性能依赖给多态系统可靠性造成的影响.利用功能-运动-动作(FMA)分解理论将多态系统分解成多个元动作,以元动作单元为研究对象,运用非齐次马尔科夫模型描述元动作单元的多状态演变过程;通过设定状态转移... 为研究单元之间相互作用所引起的性能依赖给多态系统可靠性造成的影响.利用功能-运动-动作(FMA)分解理论将多态系统分解成多个元动作,以元动作单元为研究对象,运用非齐次马尔科夫模型描述元动作单元的多状态演变过程;通过设定状态转移系数将状态转移率与依赖特性相关联,构建新的状态转移矩阵,再运用Kolmogorov微分方程求得多态单元处于各状态的概率,并利用向量通用发生函数建立考虑单元性能依赖特性的多态系统可靠性分析模型,讨论了不同依赖情形下的模型特点;以国内某卧式加工中心的分度转台系统为例验证了单元依赖特性对系统可靠性的影响.结果表明:具有依赖特性单元的状态转移率会随着对应自立单元的性能退化而改变;与单元相互独立的多态系统相比,在单元处于高性能状态时,具有单元依赖特性的多态系统可靠度更高;在单元处于低性能状态时,具有单元依赖特性的多态系统可靠度更低.研究结果可为机械系统可靠性设计和产品维修周期设计提供相应的理论依据. 展开更多
关键词 可靠性 多态系统 元动作单元 马尔科夫模型 向量通用发生函数
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高温固体自润滑涂层的制备及可靠性的研究进展 预览
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作者 袁晓静 关宁 +2 位作者 侯根良 陈小虎 马爽 《材料导报》 EI CAS CSCD 北大核心 2020年第5期61-67,共7页
高温固体自润滑涂层能够在高温环境为摩擦副界面提供高性能的固体润滑膜,解决了高温环境下传统润滑油脂失效的问题,确保摩擦副在高温环境中可靠工作,并降低了能量损耗,近年来成为摩擦学领域研究的热点问题之一,并得到了快速发展。但是,... 高温固体自润滑涂层能够在高温环境为摩擦副界面提供高性能的固体润滑膜,解决了高温环境下传统润滑油脂失效的问题,确保摩擦副在高温环境中可靠工作,并降低了能量损耗,近年来成为摩擦学领域研究的热点问题之一,并得到了快速发展。但是,在30~400℃时,诸多高温固体自润滑剂的减摩性能弱,摩擦系数较高。因此,国内外该领域科学家期望获得在30~1000℃范围内摩擦学系数低、性能良好的高性能复合型固体自润滑涂层,其主要由基础相、润滑相和增强相组成,且它们的共同作用提供涂层在高温环境下的润滑能力。最近的研究显示,金属三元氧化物基高温自润滑涂层——主要以过渡族金属三元氧化物为基础相,由含有Magnéli同源相的二元和三元氧化物润滑材料发展而来的新型高温固体自润滑材料,逐渐成为解决高温域自润滑问题的首选材料。对此,围绕高温固体自润滑涂层的工程应用,发现其面临三个方面的挑战:(1)高性能复合固体自润滑涂层的体系设计;(2)适应复杂结构的可靠制备工艺;(3)服役期间的寿命可靠性评估。针对以上三个方面的问题,本文从高温自润滑涂层的设计体系、制备工艺发展、可靠性评估三个层面进行了综述,期望为高可靠性高温自润滑涂层的制备提供技术支持。首先是在设计体系方面,发现高温固体自润滑涂层不但要满足传统固体自润滑涂层包含基础相、润滑相和增强相及其共同作用提供自润滑的要求,还要满足高温环境的特殊要求。其次,科学家们期望获得制备高性能高温固体自润滑涂层的可靠工艺,但是均受到了工艺简便性与适应能力以及高温零部件结构表面复杂度等问题的限制,从而难以实现工程化。根据高温自润滑涂层的设计要求,在梳理介绍高温固体自润滑涂层的工艺中,发现高压高超音速喷涂技术在此领域具有一定的技� 展开更多
关键词 高温自润滑涂层 结构 可靠性
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Application of reliability technologies in civil aviation: Lessons learnt and perspectives
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作者 Enrico ZIO Mengfei FAN +1 位作者 Zhiguo ZENG Rui KANG 《中国航空学报:英文版》 SCIE EI CAS CSCD 2019年第1期143-158,共16页
We consider reliability engineering in modern civil aviation industry, and the related engineering activities and methods. We consider reliability in a broad sense, referring to other system characteristics that are r... We consider reliability engineering in modern civil aviation industry, and the related engineering activities and methods. We consider reliability in a broad sense, referring to other system characteristics that are related to it, like availability, maintainability, safety and durability. We covered the entire lifecycle of the equipment, including reliability requirement identification, reliability analysis and design, verification and validation of reliability requirements(typically involved in the equipment design and development phase), quality assurance(which typically enters in the manufacturing phase), and fault diagnosis and prognosis and maintenance(which are connected to the operation phase). Lessons learnt from reliability engineering practices in civil aviation industry are given, which might serve as reference for reliability managers and engineers, also from other industries with high reliability requirements. 展开更多
关键词 CIVIL AVIATION Commercial aircraft FAULT diagnosis and PROGNOSIS Human RELIABILITY analysis Maintenance Quality control RELIABILITY design RELIABILITY engineering
无砟轨道板精调车结构可靠性分析及优化 预览 被引量:1
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作者 雷聪 于兰峰 邓星 《铁道标准设计》 北大核心 2019年第7期157-161,共5页
为提高无砟轨道板精调车结构的设计水平,考虑精调车荷载、几何尺寸和材料弹性模量等设计变量的随机性,对精调车结构进行可靠性分析、可靠性灵敏度分析和可靠性优化。首先,分析并得到精调车结构在串联失效模式下的结构功能函数;然后,运... 为提高无砟轨道板精调车结构的设计水平,考虑精调车荷载、几何尺寸和材料弹性模量等设计变量的随机性,对精调车结构进行可靠性分析、可靠性灵敏度分析和可靠性优化。首先,分析并得到精调车结构在串联失效模式下的结构功能函数;然后,运用响应面法和重要抽样方法,分析得到基于确定性优化的精调车结构的失效概率和可靠性灵敏度结果。最后,根据可靠性灵敏度分析结果,对该结构进行可靠性优化。分析精调车结构在可靠性优化前后的差异,结果表明,与确定性优化结果相比,可靠性优化使精调车结构自重增加了3.55%,但可靠度提高为0.999 999 987 7,说明设计变量的随机性对结构性能的干扰大幅减小。 展开更多
关键词 精调车 可靠性 重要抽样 可靠性灵敏度 可靠性优化
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Research on Reliability of Relaying Protection in Smart Substation 预览
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作者 Kai Wang Wanqing Li 《世界工程和技术(英文)》 2019年第2期333-338,共6页
Research on reliability of relaying protection in smart substation not only has a positive effect on the rational configuration scheme of relaying protection in smart substation, but also can promote the stability and... Research on reliability of relaying protection in smart substation not only has a positive effect on the rational configuration scheme of relaying protection in smart substation, but also can promote the stability and safety of the overall operation of power system. There are many reliability strategies for relaying protection in smart substation. In practice, the key points of relaying protection should be clarified. Based on the reality, the protection configuration should be strengthened;the voltage limited delay should be used for protection, and the protection configuration scheme of actual lines should be paid attention to, so as to improve the reliability of relaying protection in smart substation and promote the realization of stable and sustainable development of power system and smart substation. 展开更多
关键词 SMART SUBSTATION RELAYING PROTECTION RELIABILITY
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Forecasting of Software Reliability Using Neighborhood Fuzzy Particle Swarm Optimization Based Novel Neural Network 预览
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作者 Pratik Roy Ghanshaym Singha Mahapatra Kashi Nath Dey 《自动化学报:英文版》 CSCD 2019年第6期1365-1383,共19页
This paper proposes an artificial neural network(ANN) based software reliability model trained by novel particle swarm optimization(PSO) algorithm for enhanced forecasting of the reliability of software. The proposed ... This paper proposes an artificial neural network(ANN) based software reliability model trained by novel particle swarm optimization(PSO) algorithm for enhanced forecasting of the reliability of software. The proposed ANN is developed considering the fault generation phenomenon during software testing with the fault complexity of different levels. We demonstrate the proposed model considering three types of faults residing in the software. We propose a neighborhood based fuzzy PSO algorithm for competent learning of the proposed ANN using software failure data. Fitting and prediction performances of the neighborhood fuzzy PSO based proposed neural network model are compared with the standard PSO based proposed neural network model and existing ANN based software reliability models in the literature through three real software failure data sets. We also compare the performance of the proposed PSO algorithm with the standard PSO algorithm through learning of the proposed ANN. Statistical analysis shows that the neighborhood fuzzy PSO based proposed neural network model has comparatively better fitting and predictive ability than the standard PSO based proposed neural network model and other ANN based software reliability models. Faster release of software is achievable by applying the proposed PSO based neural network model during the testing period. 展开更多
关键词 Artificial neural network(ANN) FUZZY particle swarm optimization(PSO) reliability prediction software reliability
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舰空导弹舰面设备可靠性评定方法研究 预览
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作者 颜世刚 王悦 《舰船电子工程》 2019年第8期149-153,共5页
针对舰空导弹武器系统舰面设备组成结构复杂,受诸多条件限制,全系统整体参与可靠性试验鉴定困难重重,提出了如何通过简配参试系统科学分析和评估标准被试系统可靠性的方法。文章详细讨论了可靠性建模的基本概念和数学模型,简要分析了舰... 针对舰空导弹武器系统舰面设备组成结构复杂,受诸多条件限制,全系统整体参与可靠性试验鉴定困难重重,提出了如何通过简配参试系统科学分析和评估标准被试系统可靠性的方法。文章详细讨论了可靠性建模的基本概念和数学模型,简要分析了舰面设备可靠性考核的要求及特点,重点讨论了舰面设备串、并联建模、指标折算和可靠性评估方法模型,最后给出了舰空弹道舰面设备可靠性考核评估的实例应用。 展开更多
关键词 舰面设备 导弹 可靠性 任务可靠性
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An efficient algorithm for calculating Profust failure probability
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作者 Xiaobo ZHANG Zhenzhou LYU +1 位作者 Kaixuan FENG Chunyan LING 《中国航空学报:英文版》 SCIE EI CAS CSCD 2019年第7期1657-1666,共10页
For efficiently estimating the Profust failure probability based on probability input variables and fuzzy-state assumption, a General Performance Function(GPF) expression is established under the strict mathematical d... For efficiently estimating the Profust failure probability based on probability input variables and fuzzy-state assumption, a General Performance Function(GPF) expression is established under the strict mathematical derivation for the Profust reliability model. By constructing the GPF,the calculation of the Profust failure probability can be transformed into the calculation of the traditional failure probability. Then various existing methods for the traditional failure probability can be used to estimate the Profust failure probability. Due to the high efficiency of the Adaptive Kriging(AK) model and the universality of the Monte Carlo Simulation(MCS), AK inserted MCS(abbreviated as AK-MCS) has been proven to be an efficient method for estimating the failure probability. Therefore, the AK-MCS combined with the GPF(abbreviated as AK-MCS + GPF)is proposed for estimating Profust failure probability. The proposed method greatly reduces the computational cost while ensuring the accuracy. Finally, four examples are given to validate the proposed AK-MCS + GPF. The results of the examples show the rationality and the efficiency of the proposed AK-MCS + GPF. 展开更多
关键词 Failure PROBABILITY Fuzzy-state ASSUMPTION General performance function KRIGING model Profust RELIABILITY RELIABILITY
基于可靠性分析的GFRP锚杆的应用研究 预览
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作者 安瑞廷 《机械管理开发》 2019年第11期64-66,共3页
通过对巷道围岩地质条件及现场支护现状分析,得出影响锚杆可靠性的主要影响因素,建立锚杆支护事故树模型,分析得到影响支护效果的主要因素并建立极限方程和可靠度计算公式。采用验算点法计算可靠度,通过蒙特卡罗法编程计算出的玻璃钢锚... 通过对巷道围岩地质条件及现场支护现状分析,得出影响锚杆可靠性的主要影响因素,建立锚杆支护事故树模型,分析得到影响支护效果的主要因素并建立极限方程和可靠度计算公式。采用验算点法计算可靠度,通过蒙特卡罗法编程计算出的玻璃钢锚杆的可靠度表明锚杆满足现场支护需求。该研究结果可为玻璃钢(GFRP)锚杆在巷道支护中的推广应用提供科学依据,对减少支护安全事故保证巷道正常安全生产具有重要的意义。 展开更多
关键词 玻璃钢锚杆 锚杆支护 可靠度 可靠性分析 事故树
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无延时可修系统的可靠性分析与计算 预览
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作者 刘亚春 王盈 张娜 《南华大学学报:自然科学版》 2019年第1期44-46,共3页
针对无延时可修系统,在假设失效时间服从指数分布、而维修时间服从一般分布的前提下,利用补充变量法,建立了系统的可靠性模型,通过拉普拉斯变换,推导出了系统的瞬时可用度、瞬时故障频度、稳态可用度、稳态故障频度、平均开工时间、平... 针对无延时可修系统,在假设失效时间服从指数分布、而维修时间服从一般分布的前提下,利用补充变量法,建立了系统的可靠性模型,通过拉普拉斯变换,推导出了系统的瞬时可用度、瞬时故障频度、稳态可用度、稳态故障频度、平均开工时间、平均停工时间和平均周期等可靠性指标的解析表达式,并验证结论的正确性,纠正了某些参考文献的瑕疵或错误,推广了有关结果。 展开更多
关键词 可修系统 可靠性 模型 稳态可靠性指标
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A Locating Method for Reliability-Critical Gates with a Parallel-Structured Genetic Algorithm
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作者 Jie Xiao Zhan-Hui Shi +3 位作者 Jian-Hui Jiang Xu-Hua Yang Yu-Jiao Huang Hai-Gen Hu 《计算机科学技术学报:英文版》 SCIE EI CSCD 2019年第5期1136-1151,共16页
The reliability allowance of circuits tends to decrease with the increase of circuit integration and the application of new technology and materials, and the hardening strategy oriented toward gates is an effective te... The reliability allowance of circuits tends to decrease with the increase of circuit integration and the application of new technology and materials, and the hardening strategy oriented toward gates is an effective technology for improving the circuit reliability of the current situations. Therefore, a parallel-structured genetic algorithm (GA), PGA, is proposed in this paper to locate reliability-critical gates to successfully perform targeted hardening. Firstly, we design a binary coding method for reliability-critical gates and build an ordered initial population consisting of dominant individuals to improve the quality of the initial population. Secondly, we construct an embedded parallel operation loop for directional crossover and directional mutation to compensate for the deficiency of the poor local search of the GA. Thirdly, for combination with a diversity protection strategy for the population, we design an elitism retention based selection method to boost the convergence speed and avoid being trapped by a local optimum. Finally, we present an ordered identification method oriented toward reliability-critical gates using a scoring mechanism to retain the potential optimal solutions in each round to improve the robustness of the proposed locating method. The simulation results on benchmark circuits show that the proposed method PGA is an efficient locating method for reliability-critical gates in terms of accuracy and convergence speed. 展开更多
关键词 gate-level circuit RELIABILITY locating reliability-critical GATE parallel-structured genetic algorithm directing strategy SCORING mechanism
A Reliability-Based Strategy for the Analysis of Single Proton Exchange Membrane Fuel Cells 预览
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作者 Patricia da Silva Pagetti de Oliveira Vinicius Andrea +3 位作者 Elisabete Inacio Santiago Thiago Lopes Delvonei Alves de Andrade Marcelo Linardi 《能源与动力工程(英文)》 2019年第8期303-319,共17页
The development of power conversion systems based on fuel cells has been demanding reliability studies since the requirements associated with cost and durability of these technological products have become fundamental... The development of power conversion systems based on fuel cells has been demanding reliability studies since the requirements associated with cost and durability of these technological products have become fundamental to their acceptance by the energy market. The experimental part of the reliability study presented in this work consisted of performing life tests with single proton exchange membrane fuel cells (PEMFCs). The proposed reliability analysis methodology covered the application of qualitative and quantitative techniques. In the qualitative approach, a Failure Mode and Effect Analysis was developed in order to identify and evaluate all potential failures associated with the operation of fuel cells. In the quantitative approach, a statistical analysis was applied to the sample data generated in long-term steady-state tests of these devices. A two-parameter exponential distribution was fitted to data and the maximum likelihood estimate for the mean time to failure (MTTF) of the fuel cells was calculated. It is important to point out that the tests performed under the scope of this study were the first long-term experiments performed with the fuel cells produced in the laboratories of IPEN-CNEN/SP, Brazil. Although the results indicated that fuel cell performance and durability were still at a level below the targets normally established for similar commercial devices, the improvement of the main components of PEMFCs has been the objective of several projects developed at the institute. Thus, the main benefit brought by this study is the proposed methodology, which can be implemented as part of a reliability growth analysis of the fuel cells and can be integrated into the design process of these devices. 展开更多
关键词 FUEL Cells RELIABILITY DURABILITY Performance LIFE Tests LIFETIME Failure-Time
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基于PSA技术的核电厂数字化仪控系统可靠性设计及应用 被引量:1
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作者 江国进 李富 +2 位作者 孙伟 孙永滨 莫昌瑜 《核动力工程》 EI CAS CSCD 北大核心 2019年第2期99-104,共6页
传统意义上核电厂数字化仪控系统主要依靠提升设备的可靠性来满足电厂安全目标。随着监管要求的逐步提高,在提升设备可靠性基础上,基于概率论技术的设计手段逐步成为核电厂安全设计新的研究方向。本文应用概率安全评价(PSA)技术,对典型... 传统意义上核电厂数字化仪控系统主要依靠提升设备的可靠性来满足电厂安全目标。随着监管要求的逐步提高,在提升设备可靠性基础上,基于概率论技术的设计手段逐步成为核电厂安全设计新的研究方向。本文应用概率安全评价(PSA)技术,对典型电厂始发事件进行分析及研究,之后对仪控设计方案整体进行PSA建模,再将其置于电厂PSA模型中,通过定量评估分析,识别薄弱环节,给出优化改进措施。在此基础上提出了一套确保核电厂仪控系统满足整体安全目标的可靠性设计流程。 展开更多
关键词 概率安全评价(PSA) 可靠性 始发事件 可靠性模型
RCFA在某家电制造企业TSQ中的应用 预览
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作者 张来平 杜旭东 +1 位作者 范忠辉 徐新兵 《电子产品可靠性与环境试验》 2019年第A01期46-50,共5页
电子产品的可靠性是目前广大消费者和制造商的重要关注点,然而,由于很多企业的技术水平有限或分析手段欠缺,很多质量问题无法从根本上得到解决。基于此,工信部电子五所首创了质量可靠性整体解决方案(TSQ),通过诊断、分析、方案、实施和... 电子产品的可靠性是目前广大消费者和制造商的重要关注点,然而,由于很多企业的技术水平有限或分析手段欠缺,很多质量问题无法从根本上得到解决。基于此,工信部电子五所首创了质量可靠性整体解决方案(TSQ),通过诊断、分析、方案、实施和固化等5个关键流程,实现了企业质量可靠性的提升与改进。故障根本原因分析(RCFA)作为质量可靠性整体解决关键流程分析的主要工具之一,应用得非常广泛。列举了故障根本原因分析在某家电制造公司质量可靠性整体解决过程中的应用,供广大业内人员参考。 展开更多
关键词 故障根本原因分析 可靠性 质量问题整体解决
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铣削加工表面位置误差的可靠性灵敏度分析 预览
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作者 宋相强 李庆伟 +1 位作者 高娓 黄贤振 《机械设计与制造》 北大核心 2019年第9期86-88,92共4页
铣削加工表面位置误差对工件的加工精度起决定性作用,而在铣削过程中的切削参数是随机的,传统铣削加工位置误差预测方法忽略了随机因素的影响,容易产生较大的分析误差。首先建立铣削加工过程动态模型,而后采用全离散法获取铣削加工位置... 铣削加工表面位置误差对工件的加工精度起决定性作用,而在铣削过程中的切削参数是随机的,传统铣削加工位置误差预测方法忽略了随机因素的影响,容易产生较大的分析误差。首先建立铣削加工过程动态模型,而后采用全离散法获取铣削加工位置误差随主轴转速的变化规律,最后推导了一种基于Kriging拟合的蒙特卡罗分析方法,开展铣削加工过程可靠性和可靠性灵敏度分析。数值算例表明,所述方法具有较高的精度和效率,且可靠性和可靠性灵敏度分析结果对于评价铣削加工过程的可靠性以及铣削加工参数的灵敏度具有重要的指导意义。 展开更多
关键词 铣削 表面位置误差 KRIGING 可靠性 可靠性灵敏度
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考虑Kriging模型的击针疲劳强度可靠性分析 预览
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作者 张雅 方峻 《机械设计与制造》 北大核心 2019年第7期172-176,共5页
击针是枪械的重要部分,随着射击次数的增加,击针可能产生断裂,影响正常使用。疲劳断裂是击针失效的主要因素,而采用随机有限元模型的击针疲劳可靠性分析计算量大,为此提出了一种考虑疲劳损伤退化过程的Kriging模型分析方法。首先利用有... 击针是枪械的重要部分,随着射击次数的增加,击针可能产生断裂,影响正常使用。疲劳断裂是击针失效的主要因素,而采用随机有限元模型的击针疲劳可靠性分析计算量大,为此提出了一种考虑疲劳损伤退化过程的Kriging模型分析方法。首先利用有限元对部件进行应力应变分析,产生了计算疲劳损伤所需的数据,再由Kriging模型模拟结构应力函数,利用Neuber局部应力应变分析法求出击针的疲劳损伤,最后由Kriging模型结合蒙特卡洛方法模拟抽样随机因素下的单发射击时的损伤大小,拟合了击针疲劳损伤退化量的分布函数,并由此退化数据分析评估了击针的可靠性。结果表明:该方法较为准确且计算量小,更适用于疲劳可靠性问题的快速评估。 展开更多
关键词 击针 可靠性 KRIGING模型 局部应力应变 可靠寿命
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长处和困难问卷中文版的信度概化分析
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作者 许文兵 王孟成 +3 位作者 邓嘉欣 刘惠华 曾红 杨文登 《中国临床心理学杂志》 CSSCI CSCD 北大核心 2019年第1期67-72,共6页
目的:检验中文版长处与困难问卷信度系数(α系数、重测信度系数和分半信度)的稳定性,以及探讨α系数的影响因素。方法:根据预先设定的文献纳入标准,本研究共纳入46篇论文的60个样本(N=114576),采用信度概化元分析技术对中文版长处与困... 目的:检验中文版长处与困难问卷信度系数(α系数、重测信度系数和分半信度)的稳定性,以及探讨α系数的影响因素。方法:根据预先设定的文献纳入标准,本研究共纳入46篇论文的60个样本(N=114576),采用信度概化元分析技术对中文版长处与困难问卷的信度系数进行分析。结果:(1)三种信度的异质性显著,随机效应模型估计的α均值分别为:困难分量表0.749、情绪症状分量表0.686、品行问题分量表0.593、多动与注意不能分量表0.741、同伴关系分量表0.397和亲社会行为分量表0.743。(2)通过混合效应模型的调节分析发现:出版年份、使用版本、文献来源、出版物类型这4类研究特征对各分量表分数的α系数有不同程度的调节作用。在样本特征方面,东部沿海地区和儿童群体α系数都较低。结论:品行问题和同伴关系分量表可靠性低,题项异质程度大,建议修订题项。同时应注意样本特征和研究特征对α系数的影响,特别是用于东部沿海地区及儿童样本时需要谨慎。 展开更多
关键词 长处和困难问卷 信度 信度概化 元分析
A frequency domain reliability analysis method for electromagnetic problems based on univariate dimension reduction method
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作者 PING MengHao HAN Xu +4 位作者 JIANG Chao ZHONG JianFeng XIAO XiaoYa HUANG ZhiLiang &WANG ZhongHua 《中国科学:技术科学英文版》 SCIE EI CAS CSCD 2019年第5期787-798,共12页
In this paper, a class of electromagnetic field frequency domain reliability problem is first defined. The frequency domain reliability refers to the probability that an electromagnetic performance indicator can meet ... In this paper, a class of electromagnetic field frequency domain reliability problem is first defined. The frequency domain reliability refers to the probability that an electromagnetic performance indicator can meet the intended requirements within a specific frequency band, considering the uncertainty of structural parameters and frequency-variant electromagnetic parameters.And then a frequency domain reliability analysis method based on univariate dimension reduction method is proposed, which provides an effective calculation tool for electromagnetic frequency domain reliability. In electromagnetic problems, performance indicators usually vary with frequency. The method firstly discretizes the frequency-variant performance indicator function into a series of frequency points’ functions, and then transforms the frequency domain reliability problem into a series system reliability problem of discrete frequency points’ functions. Secondly, the univariate dimension reduction method is introduced to solve the probability distribution functions and correlation coefficients of discrete frequency points’ functions in the system. Finally, according to the above calculation results, the series system reliability can be solved to obtain the frequency domain reliability, and the cumulative distribution function of the performance indicator can also be obtained. In this study,Monte Carlo simulation is adopted to demonstrate the validity of the frequency domain reliability analysis method. Three examples are investigated to demonstrate the accuracy and efficiency of the proposed method. 展开更多
关键词 electromagnetic field frequency DOMAIN RELIABILITY system RELIABILITY RANDOM process DISCRETIZATION univariate DIMENSION reduction METHOD
Comparative Reliability of Berg Balance Scale and MAS Tests in People with Neurological Disorders 预览
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作者 Thomas Besios Aggeloussis Nikolaos +1 位作者 Gourgoulis Vassilios Mauromatis Giorgos 《神经系统科学与医药(英文)》 2019年第3期224-231,共8页
Background: In recent years, many tests have been developed to evaluate the mobility and functional capacity of people with neurological disorders (Hemiplegia, MS). The purpose of this study was to test the reliabilit... Background: In recent years, many tests have been developed to evaluate the mobility and functional capacity of people with neurological disorders (Hemiplegia, MS). The purpose of this study was to test the reliability and additionally to determine the measurement error of Modified Ashworth Scale and BBS in adults with neurological disorders (hemiplegia, MS). Methods: In the study of tests 20 adults (11 with multiple sclerosis and 9 with hemiplegia) who were retrospectively registered, participated. The average age of adults was 38.7 ± 13.9 years old and their average body mass was 65.1 ± 13.1 kgr. The Greek version of the tests and a Nikon 5300 digital camera for video recording were used for data collection. ICC was calculated, by means of a two-way ANOVA model. Results: The results showed that there were no statistically significant differences between the two independent evaluators and that the BBS (ICC > 0.989) had strong reliability. The reliability of Modified Ashworth Scale has been found to be average: K = 0.502, (p Conclusions: Overall, the results of the present investigation provided considerable evidence suggesting that the test BBS and MAS are reliable and can be used to evaluate kinetic and balance disorders. Therefore, it was concluded that the tests should be applied in order to reliably estimate the mobility and functional ability of adults with neurological disorders. More research shall be carried out in the future on other patients in order to evaluate the reliability of the above tests. 展开更多
关键词 RELIABILITY BBS-MAS HEMIPLEGIA MS
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