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New method of fault diagnosis of rotating machinery based on distance of information entropy

Houjun SU, Tielin SHI, Fei CHEN, Shuhong HUANG

《机械工程前沿（英文）》 2011年第6卷第2期页码 249-253 doi: 10.1007/s11465-011-0124-3

摘要：

This paper introduces the basic conception of information fusion and some fusion diagnosis methods commonly used nowadays in rotating machinery. From the thought of the information fusion, a new quantitative feature index monitoring and diagnosing the vibration fault of rotating machinery, which is called distance of information entropy, is put forward on the basis of the singular spectrum entropy in time domain, power spectrum entropy in frequency domain, wavelet energy spectrum entropy, and wavelet space feature entropy in time-frequency domain. The mathematic deduction suggests that the conception of distance of information entropy is accordant with the maximum subordination principle in the fuzzy theory. Through calculation it has been proved that this method can effectively distinguish different fault types. Then, the accuracy of rotor fault diagnosis can be improved through the curve chart of the distance of information entropy at multi-speed.

关键词： rotating machinery information fusion fault diagnosis Information entropy distance of the information entropy

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Application of entropy-based fuzzy matter-element analysis in seepage monitoring of RCC dam

Chongshi GU, Zhijun ZHANG, Xin CAI, Yue HOU

《结构与土木工程前沿（英文）》 2011年第5卷第1期页码 105-111 doi: 10.1007/s11709-010-0015-4

摘要： Taking account of the fuzzy results of the seepage monitoring analysis of roller compacted concrete (RCC) dam and uncertainties of the individual indicator evaluation, the fuzzy matter-element model of seepage monitoring of RCC dam analysis has been established with the use of the fuzzy matter-element analysis theory and the concept of euclid approach degree. The use of entropy theory can calculate the weighting factor through the disorder utility values of the information reflected by the data itself, which can effectively avoid the problems of weight distribution and uncertainties of subjective judgments of the seepage monitoring analysis of roller compacted concrete dam. And further the example shows that the analysis of entropy-based fuzzy matter-element analysis model of the seepage monitoring of roller compacted concrete dam is in accordance with the actual situation, which verifies the effectiveness of the method.

关键词： information entropy fuzzy matter-element roller compacted concrete (RCC) dam seepage analysis

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基于信息熵和深度置信网络的涡轮发动机在有限传感器下的故障诊断仿真研究 Article

De-long FENG,Ming-qing XIAO,Ying-xi LIU,Hai-fang SONG,Zhao YANG,Ze-wen HU

《信息与电子工程前沿（英文）》 2016年第17卷第12期页码 1287-1304 doi: 10.1631/FITEE.1601365

摘要：精确故障诊断是预测与健康管理的一个重要部分。它能避免事故的发生，延长设备使用寿命，还能降低设备维修保养费用。本文研究涡轮发动机的故障诊断。由于发动机工作在高温、高压、高转速的严峻环境中，不能安装过多传感器，因此我们无法获得足够多的传感器数据，以至于采用现有算法不能进行精确的潜在故障诊断。本文针对复杂环境下有限传感器数据的发动机故障诊断问题，提出了一种基于信息熵的深度置信网络方法。首先介绍了几种信息熵，并基于单信号熵提出了联合复杂信息熵。其次，分析了深度置信网络的构成，提出了基于信息熵的深度置信网络方法。验证实验表明，与现有的机器学习算法比较，该方法的诊断精度大大提高。

关键词：深度置信网络；信息熵；故障诊断；发动机

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Principle of maximum entropy for reliability analysis in the design of machine components

Yimin ZHANG

《机械工程前沿（英文）》 2019年第14卷第1期页码 21-32 doi: 10.1007/s11465-018-0512-z

摘要： We studied the reliability of machine components with parameters that follow an arbitrary statistical distribution using the principle of maximum entropy (PME). We used PME to select the statistical distribution that best fits the available information. We also established a probability density function (PDF) and a failure probability model for the parameters of mechanical components using the concept of entropy and the PME. We obtained the first four moments of the state function for reliability analysis and design. Furthermore, we attained an estimate of the PDF with the fewest human bias factors using the PME. This function was used to calculate the reliability of the machine components, including a connecting rod, a vehicle half-shaft, a front axle, a rear axle housing, and a leaf spring, which have parameters that typically follow a non-normal distribution. Simulations were conducted for comparison. This study provides a design methodology for the reliability of mechanical components for practical engineering projects.

关键词： machine components reliability arbitrary distribution parameter principle of maximum entropy

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High-order phase-field model with the local and second-order max-entropy approximants

Fatemeh AMIRI

《结构与土木工程前沿（英文）》 2019年第13卷第2期页码 406-416 doi: 10.1007/s11709-018-0475-5

摘要： We approximate the fracture surface energy functional based on phase-field method with smooth local maximum entropy (LME) and second-order maximum entropy (SME) approximants. The higher-order continuity of the meshfree methods such as LME and SME approximants allows to directly solve the fourth-order phase-field equations without splitting the fourth-order differential equation into two second-order differential equations. We will first show that the crack surface functional can be captured more accurately in the fourth-order model with smooth approximants such as LME, SME and B-spline. Furthermore, smaller length scale parameter is needed for the fourth-order model to approximate the energy functional. We also study SME approximants and drive the formulations. The proposed meshfree fourth-order phase-field formulation show more stable results for SME compared to LME meshfree methods.

关键词： second-order maximum entropy local maximum entropy second- and fourth-order phase-field models B-spline

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基于机械诊断信息的设备运行可靠性研究

何正嘉,蔡改改,申中杰,曹宏瑞,李兵

《中国工程科学》 2013年第15卷第1期页码 9-14

摘要：

针对传统可靠性分析方法必须依赖大样本统计数据、利用概率统计求解设备可靠性的不足，提出两种利用运行状态信息实现小样本条件下设备运行可靠性评估的方法：基于归一化小波信息熵的可靠性评估和基于损伤定量识别的可靠性评估。基于归一化小波信息熵的可靠性评估对设备运行过程中的振动信号采用第二代小波包进行分解与重构，获得多个分解频带信号，计算分解频带信号的相对能量和归一化信息熵，根据归一化信息熵获取反映设备运行状态可靠性的重要指标——可靠度；基于损伤定量识别的可靠性评估定义了新的运行可靠性评价指标——隶属可靠度，在故障定量诊断的基础上，建立了损伤程度与运行可靠性评价指标之间的联系。在制氧压缩机运行可靠性评估和机车轮对轴承运行可靠性评估的成功应用，表明所提出的方法合理、有效，为机械设备实现缺乏大样本、非概率统计模型的可靠性评估提供了新理论与新技术。

关键词：机械设备运行可靠性归一化信息熵隶属可靠度

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不完备模糊信息系统

杨习贝,杨静宇,吴陈,傅凡

《中国工程科学》 2006年第8卷第7期页码 47-53

摘要：

以不完备模糊信息系统为研究对象，建立了其中的模糊相容关系及模糊粗糙上、下近似集。在此基础上，探讨了论域上的模糊覆盖问题并提出了覆盖的3种运算形式；定义了2种新的模糊粗糙熵以讨论不完备模糊信息系统中的不确定性因素，证明了不确定因素的变化与度量强度之间的重要关系；建立了一种度量部分模糊知识依赖的新方法，获得了一些新的定理结果证明。

关键词：不完备模糊信息系统模糊相容关系模糊粗糙集模糊覆盖模糊粗糙熵模糊知识依赖

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Maximum entropy based finite element analysis of porous media

Emad NOROUZI, Hesam MOSLEMZADEH, Soheil MOHAMMADI

《结构与土木工程前沿（英文）》 2019年第13卷第2期页码 364-379 doi: 10.1007/s11709-018-0470-x

摘要： The maximum entropy theory has been used in a wide variety of physical, mathematical and engineering applications in the past few years. However, its application in numerical methods, especially in developing new shape functions, has attracted much interest in recent years. These shape functions possess the potential for performing better than the conventional basis functions in problems with randomly generated coarse meshes. In this paper, the maximum entropy theory is adopted to spatially discretize the deformation variable of the governing coupled equations of porous media. This is in line with the well-known fact that higher-order shape functions can provide more stable solutions in porous problems. Some of the benchmark problems in deformable porous media are solved with the developed approach and the results are compared with available references.

关键词： maximum entropy FEM fully coupled multi-phase system porous media

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High-entropy catalysts for electrochemical water-electrolysis of hydrogen evolution and oxygen evolution

《能源前沿（英文）》 2024年第18卷第3期页码 265-290 doi: 10.1007/s11708-023-0892-6

摘要： High entropy materials (HEMs) have developed rapidly in the field of electrocatalytic water-electrolysis for oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) due to their unique properties. In particular, HEM catalysts are composed of many elements. Therefore, they have rich active sites and enhanced entropy stability relative to single atoms. In this paper, the preparation strategies and applications of HEM catalysts in electrochemical water-electrolysis are reviewed to explore the stabilization of HEMs and their catalytic mechanisms as well as their application in support green hydrogen production. First, the concept and four characteristics of HEMs are introduced based on entropy and composition. Then, synthetic strategies of HEM catalysts are systematically reviewed in terms of the categories of bottom-up and top-down. The application of HEMs as catalysts for electrochemical water-electrolysis in recent years is emphatically discussed, and the mechanisms of improving the performance of electrocatalysis is expounded by combining theoretical calculation technology and ex-situ/in situ characterization experiments. Finally, the application prospect of HEMs is proposed to conquer the challenges in HEM catalyst fabrications and applications.

关键词： high-entropy electrocatalysis synthetic methods water-electrolysis hydrogen and oxygen evolutions

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Optimization of cold-end system of thermal power plants based on entropy generation minimization

《能源前沿（英文）》 2022年第16卷第6期页码 956-972 doi: 10.1007/s11708-021-0785-5

摘要： Cold-end systems are heat sinks of thermal power cycles, which have an essential effect on the overall performance of thermal power plants. To enhance the efficiency of thermal power plants, multi-pressure condensers have been applied in some large-capacity thermal power plants. However, little attention has been paid to the optimization of the cold-end system with multi-pressure condensers which have multiple parameters to be identified. Therefore, the design optimization methods of cold-end systems with single- and multi-pressure condensers are developed based on the entropy generation rate, and the genetic algorithm (GA) is used to optimize multiple parameters. Multiple parameters, including heat transfer area of multi-pressure condensers, steam distribution in condensers, and cooling water mass flow rate, are optimized while considering detailed entropy generation rate of the cold-end systems. The results show that the entropy generation rate of the multi-pressure cold-end system is less than that of the single-pressure cold-end system when the total condenser area is constant. Moreover, the economic performance can be improved with the adoption of the multi-pressure cold-end system. When compared with the single-pressure cold-end system, the excess revenues gained by using dual- and quadruple-pressure cold-end systems are 575 and 580 k$/a, respectively.

关键词： cold-end system entropy generation minimization optimization economic analysis genetic algorithm (GA)

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区间值信息系统中基于信息熵的属性约简 Article

Jian-hua DAI,Hu HU,Guo-jie ZHENG,Qing-hua HU,Hui-feng HAN,Hong SHI

《信息与电子工程前沿（英文）》 2016年第17卷第9期页码 919-928 doi: 10.1631/FITEE.1500447

摘要：概要：区间值数据用来表示包含观察值的不确定性。区间值信息系统的处理有助于拓展粗糙集理论的应用范畴。属性约简是区间值数据分析的一个关键问题。现有针对传统单值数据的方法不适用于区间值数据。目前，关注区间值数据约简的研究还相对较少。本文从信息论的角度提出了一个区间值数据的属性约简框架，定义了区间值信息系统中的熵、条件熵以及联合熵等概念，继而构造了属性约简算法。实验结果表明所构造的方法是有效的。

关键词：粗糙集理论；区间值数据；属性约简；熵

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Entropy flow, entropy generation, exergy flux, and optimal absorbing temperature in radiative transfer

Zeshao CHEN, Songping MO, Peng HU, Shouli JIANG, Gang WANG, Xiaofang CHENG,

《能源前沿（英文）》 2010年第4卷第3期页码 301-305 doi: 10.1007/s11708-010-0006-0

摘要： Taking nonequilibrium radiative heat transfer between two surfaces as an example, the nonequilibrium thermodynamics of radiation is studied and discussed. The formulas of entropy flow, entropy generation, exergy flux, and optimal temperature of absorbing surface for maximum exergy output are derived. The result is a contribution to the thermodynamic analysis and optimization of solar energy utilization and can be applied in more complex radiative heat transfer cases.

关键词： radiative heat transfer entropy generation exergy thermodynamics