基于Alopex神经网络的旋转机械故障诊断专家系统

提出了一种可以减小网络规模的故障表示方法,并将Alopex算法引入神经网络模型的训练过程,将人工神经网络与规则推理相结合,建立了旋转机械故障诊断的神经网络专家系统。该系统充分利用了神经网络与规则推理的优点,采用正反向混合推理方式调用知识库中的各种知识进行诊断。采用二进制数码表示机械的各种故障,基于Alopex算法训练神经网络。建立的专家系统克服了基于规则专家系统的自学习困难问题和基于神经网络诊断系统的系统控制能力弱的缺点,具有较强的诊断能力。     

工程设计KBE系统(Ⅱ):知识处理技术

针对日益兴起的工程设计 KBE技术的研究和应用 ,本文对工程设计 KBE中的关键技术——知识处理技术 (知识表示和推理 ,知识获取 )进行了详细的论述 ,主要解决了基于框架 -规则的知识表示和推理 ,基于事例的推理以及神经网络的学习和推理在工程设计中的应用方法。该技术在应用中具有集成多种知识表示方法 ,能够充分利用工程领域知识的优势 ,并在注塑模模架设计中得到了有效的应用     

智能故障诊断研究的模型与方法

在机械设备故障诊断的研究中，神经网络诊断系统和符号推理诊断系统基本上是分开研究的。本文分析了这两种诊断系统同人的思维的联系与区别，指出了它们各自的优缺点，并且提出了一种适合故障诊断的基于神经网络、符号推理和人的智能的综合智能模型。     

基于规则的模糊神经网络故障诊断专家系统

提出了一种基于规则的模糊神经网络专家系统诊断方法,该方法采用了广义三层规则库结构及推理机制,把Ｒｕｌｅ型的模糊联想记忆器作为专家系统的分类和综合算法,使基于规则的知识处理方法与模糊神经网络有机地结合在一起。并讨论了模糊神经网络输入和输出模糊化的问题。为旋转机械故障诊断专家系统提供了一个易于实现的框架结构。     

汽轮发电机组故障智能诊断系统的研究

本文以汽轮发电机组为对象，研制了一个智能故障诊断系统，该系统将传统专家系统的符号推理与神经网络的并行计算相结合，采用并行推理为主，串行推理为辅的混合推理机制，并在推理过程中采用神经网络技术对机组的运行信息进行智能识加以自动获取诊断所需要的症状信息，且以人工神经网络技术为基础通过对诊断实例的自学习来实现专家系统的知识获取，实践表明通过以上方法可以提高诊断系统的智能化水平，自动化程度和诊断结果的准确性     

实例推理中基于ART算法的动态记忆模型的研究

提出了一种基于神经网络的工艺设计实例推理索引模型，与现存大多数实例推理系统不同，该方法用神经网络实现实例的动态分类和索引。实例层次分类的３层结构，为实现基于符号处理的实例推理求解模式向基于神经计算的模式识别求解模式映射提供了条件。神经网络的自适应，自学习能力将减少系统的日常维护工作，该方法的优点在于实例的高速，有效检索，知识获取的简化等。     

基于异构知识集成推理策略的研究

研究了基于异构知识处理的集成推理方法,提出了异构知识的概念,探讨了集成推理的结构模型和求解策略,论述了基于符号知识推理、基于实例推理的推理技术和人工神经网络的学习算法三者的有机结合实现集成推理,体现了知识工程技术与计算智能技术相结合的优势。     

薄板裂纹诊断的专家系统

将人工神经网络与规则推理相结合,建立了薄板裂纹诊断的专家系统,该系统充分利用神经网络与规则推理的优点,采用正反向混合推理方式调用知识库中的各种知识进行薄板结构的裂纹诊断,采用基于实验的计算机仿真技术建立裂纹诊断的标准谱,基于模拟退火算法训练神经网络,实例表明,本文建立的专家系统克服了基于规则专家系统的自学习困难问题和基于神经网络诊断系统系统控制能力弱的缺点,具有较强的诊断能力。     

案例推理在印刷机械故障诊断中的应用

借助于案例推理技术在知识获取、易于理解方面的优势,结合印刷机械设备的特点,将基于案例推理的方法引入到印刷设备的故障诊断领域,研究基于案例推理技术的原理和方法,详细论述了案例推理在设备故障诊断系统中的实现过程,最后给出了该方法在印刷机械设备故障诊断中的应用实例。     

智能设计集成推理技术的研究

本文研究集成推理方法处理异构知识。首先提出了集成推理的结构模型和求解策略,探讨了集成推理的关键技术,分别论述了基于符号知识推理、基于实例推理的推理技术和人工神经网络的学习算法,然后通过三者的有机结合,实现集成的推理,体现了知识工程技术与计算智能技术相结合,不仅提高了处理知识的能力,而且提高了问题求解的效率,刻划了智能设计的思维规律,为工程设计问题智能求解建立了灵活的集成机制,最后给出了应用实例。     

Minimal Realization of Linear Graph Models for Multi-physics Systems

An engineering system may consist of several different types of components,belonging to such physical"domains"as mechanical,electrical,fluid,and thermal.It is t...     

On the Relation of Load to Average Gap in the Contact Between Surfaces with Longitudinal Roughness

A computer simulation model for the contact between longitudinally-oriented rough surfaces has been formulated. This model closely duplicates the actual surf ace contact deformation behavior by taking into account the elastic interactions between the asperities. There were no assumptions made about the shapes, or any deformation behavior of the asperities, except for their obeying the laws of elasticity. The plastic deformations on the high asperity peaks were taken into account by setting a ceiling on their contact pressures at the material hardness value. The simulations used real surface profiles which were digitized from unworn circumferentially ground steel surfaces. Each pair of these profiles was mathematically combined to form an equivalent rough profile pressing against an infinitely rigid flat and having the appropriately adjusted elastic modulus. A total of 28 different pairs of profiles were used in the simulations. Each contacting pair was subjected to 30 different load levels and the local contact pressures and deformations were calculated. The contact simulations yielded some important mathematical relationships between parameters, such as the real area of contact, average gap, and average asperity load through statistical curve fitting. Two analytical functions were generated to relate the average load to average gap and the real area of contact to load.     

三绕组变压器的双绕组等效建模及在Matpower中的应用

针对实际电网存在着大量的三绕组变压器,但国际上一些著名商业软件,如BPA仿真软件、Matpower这一权威潮流计算开源软件,均只提供双绕组变压器模型,限制了其在具有三绕组变压器的电力系统中的应用的问题,潮流计算是自主开发的电力系统各种应用软件的核心模块,因此依托国际权威开源程序进行二次开发,是一种较好的选择。对Matpower要求的数据格式进行了归纳,对变压器的一般的等值电路及带理想变压器的等值电路和带标幺值的等值电路进行了分析研究,提出了三绕组变压器转换为双绕组等效模型的建模方法,使得原先只适应双绕组变压器的潮流计算软件可以适用于三绕组变压器电网的潮流计算;最后以Matpower软件为例进行了案例计算,并用PSASP仿真软件进行对比验证。研究结果证明,所提出的建模方法是有效的。     

Quantum Cooperative Robotics and Autonomy

The intersection of Quantum Technologies and Robotics Autonomy is explored in the present paper.The two areas are brought together in establishing an interdisci...     

电站锅炉模糊风险评价方法研究与应用

针对电站锅炉风险等级评价问题,将模糊综合评价技术应用到电站锅炉风险等级评价中。开展了电站锅炉失效影响因素及模糊评价因素的重要程度分析,建立了一套科学合理适于在线评价的电站锅炉风险评价体系,提出了模糊综合评价技术与改进的模糊层次分析法相结合的模糊风险评价方法,利用改进的模糊层次分析法计算了指标体系中各层指标权重。对某一台电站锅炉的实际运行工况影响子因素进行了模糊风险评价,采用模糊合成算子进行模糊综合运算得到电了站锅炉运行工况影响子因素的评价向量。研究结果表明:电站锅炉的运行工况影响子因素的风险评价等级为第6级,失效可能性等级为小,该电站锅炉运行工况良好。     

考虑进油孔有限长滑动轴承油膜力的近似解析解

针对具有进油孔的有限长滑动轴承油膜力求解问题,采用变分原理和分离变量法,求得了有限长滑动轴承油膜压力分布的近似解析表达式。将油膜压力分布的近似解析表达式在油膜存在区域上进行积分,即得到了油膜力。将提出的计算有限长滑动轴承油膜力方法与无限长轴承模型、有限元方法的计算结果进行了比较,发现了提出的方法与有限元方法的计算结果很接近。最后,研究了进油孔位置和进油压力对油膜存在区域、油膜力等的影响,研究结果表明进油孔位置和进油压力对油膜存在区域和油膜力有较大的影响。     

Fifth International Summer School on Screw-Theory Based Methods in Robotics

正3-11 September,2014University of Bologna,Bologna,Italy www.summerscrews.org summerscrews2014.ing.unibo.it SUMMER 20SCREWS 14In 2014,our screw-theory school comes to the world's oldest university.In early September,Summer Screws'14 will gather six experts in the application of screw theory in robotics and up to 40 participants at the University of Bologna,Bologna,Italy.The school will teach attendees how to apply existing methods and empower them to develop new ones in their own research.The basic theoretical notions will be introduced in a rigorous manner,emphasizing examples,applications,and exercises.Scholarships are available.     

交通荷载作用下桥梁结构参数识别方法

应用动力节点加载法,将作用在桥梁上的交通荷载转化为等效节点荷载,再用两步构造法识别结构物理参数.第1步,用Newmark-β方法变换结构运动方程,并用结构的加速度响应求得变换空间内的位移、速度和加速度响应;第2步,基于最小二乘原理,构造出变换空间内求解结构参数的递推式,进行结构物理参数识别.数值模拟结果表明,在交通荷载作用下,该方法能够快速、准确地进行桥梁结构参数识别.     

INDUSTRIAL ENGINEERING AND VISUALISATION-A PRODUCT DEVELOPMENT PERSPECTIVE

Taking the actual project of teaching and researching process for example, the relationship between the industrial engineering and product development is discussed. And use the novel visualization technology to support the industrial engineering and product development. How to use the new computer modeling and simulating technologies to support the product development and industrial engineering, is introduced especially. The support includes both domestic products and industrial systems. The visualization and computer technologies take a very important role in some system or multi-direction modeling, those technologies mentioned above can help the industrial engineers study the effect of design on the whole life circle, including the producing steps. So the engineers can avoid making the wrong decision which may cause bad effects on the whole industrial engineering.     

Non-monotonic material contrast in scanning ion and scanning electron images

30 keV Ga⁺ focused ion beam induced secondary electron (iSE) imaging was used to determine the relative contrast between several materials. The iSE signal compared from C, Si, Al, Ti, Cr, Ni, Cu, Mo, Ag, and W metal layers does not decrease with an increase in target atomic number Z₂, and shows a non-monotonic relationship between contrast and Z₂. The non-monotonic relationship is attributed to periodic fluctuations of the stopping power and sputter yield inherent to the ion–solid interactions. In addition, material contrast from electron-induced secondary electron (eSE) and backscattered electron (BSE) images using scanning electron microscopy (SEM) also shows non-monotonic contrast as a function of Z₂, following the periodic behavior of the stopping power for electron–solid interactions. A comparison of the iSE and eSE results shows similar relative contrast between the metal layers, and not complementary contrast as conventionally understood. These similarities in the contrast behavior can be attributed to similarities in the periodic and non-monotonic function defined by incident particle–solid interaction theory.