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Gyroscope Fault Diagnosis Using Fuzzy SVM to Unbalanced Samples

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Transactions of Nanjing University of Aeronautics and Astronautics 2015年第1期32卷 16-21页

作者：罗秋凤张锐李勇杨忠清 UAV Research Institute Nanjing University of Aeronautics and Astronautics Department of Automation Nanjing University of Aeronautics and Astronautics

A novel fuzzy support vector machine based on unbalanced samples(FSVM-US)is proposed to solve the high false positive rate problem since the gyroscope output is susceptible to unmanned aerial vehicle(UAV)airborne electromagnetic environment and the gyroscope abnormal signal sample is rather ***,the standard deviation of samples projection to normal vector for SVM classifier hyper plane is *** imbalance feature expression reflecting the hyper plane shift for the number imbalance between samples and the dispersion imbalance within samples is *** the same time,the denoising factor is designed as the exponential decay function based on the Euclidean distance between each sample and the class ***,the imbalance feature expression and denoising factor are configured into the membership *** sample has its own weight denoted the importance to the ***,the classification simulation experiments on the gyroscope fault diagnosis system are conducted and FSVM-US is compared with the standard SVM,FSVM,and the four typical class imbalance learning(CIL)*** results show that FSVM-US classifier accuracy is 12% higher than that of the standard ***,FSVM-US is superior to the four CIL methods in total ***,the FSVMUS noise tolerance is also 17% higher than that of the standard SVM.

关键词： fault diagnosis gyroscope fuzzy support vector machine(FSVM) unbalanced samples membership function

A collocation reliability analysis method for probabilistic and fuzzy mixed variables

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Science China(Physics,Mechanics & Astronomy) 2014年第7期57卷 1318-1330页

作者： XU MengHui QIU ZhiPing Institute of Solid Mechanics Beihang University

The main bottleneck of the reliability analysis of structures with aleatory and epistemic uncertainties is the contradiction between the accuracy requirement and computational *** methods are either computationally unaffordable or with limited application ***,a new technique for capturing the minimal and maximal point vectors instead of the extremum of the function is developed and thus a novel reliability analysis method for probabilistic and fuzzy mixed variables is *** fuzziness propagation in the random reliability,which is the focus of the present study,is performed by the proposed method,in which the minimal and maximal point vectors of the structural random reliability with respect to fuzzy variables are calculated dimension by dimension based on the Chebyshev orthogonal polynomial ***-Order,Second-Moment(FOSM)method which can be replaced by its counterparts is utilized to calculate the structural random *** the accuracy and efficiency of the proposed method are validated by numerical examples and engineering applications introduced in the paper.

关键词： reliability membership function probabilistic variable fuzzy variable mixed uncertain variables FOSM

Application of fuzzy theory on earthquake damage rate estimation of buildings

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Journal of Central South University 2014年第6期21卷 2454-2459页

作者：邵扬威吴玉祥高士峰黄麒然张宽勇 Graduate Institute of Engineering Technology National Taipei University of Technology Department of Mechanical Engineering China University of Science and Technology Graduate Institute of Civil and Disaster Prevention Engineering National Taipei University of Technology

Variations between earthquakes result in many factors that influence post-earthquake building damage(e.g.,ground motion parameters,building structure,site information,and quality of construction).Consequently,it is necessary to develop an appropriate building damage-rate estimation *** building damage survey data were recorded and constructed into files by the Architecture and Building Research Institute(ABRI),Taiwan for the 1999 Chi-Chi earthquake in the Nantou region as a basis for developing a building damage rate estimation model by applying fuzzy theory to express the fragility curves of buildings as a membership *** verification was performed using post-earthquake building damage data in the Taichung city that suffered relatively severe *** indicate that fuzzy theory can be applied to predict building damage rates and that the estimated results are similar to actual disaster *** of disaster damage using building damage rates can provide a reference for immediate disaster response during earthquakes and for regular disaster prevention and rescue planning.

关键词： fuzzy theory membership function fragility curve earthquake damage rate

RPL Based on Triangle Module Operator for AMI Networks

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China Communications 2018年第5期15卷 162-172页

作者： Yanan Cao Muqing Wu Beijing Laboratory of Advanced Information Networks Beijing University of Posts and Telecommunications

the routing protocol for low-power and lossy networks(RPL) has been used in advanced metering infrastructure(AMI)which could provide two-way communication between smart meters and city *** improve the network performance of AMI networks, this paper proposed an improved algorithm of RPL based on triangle module operator(IAR-TMO). IAR-TMO proposes membership functions of the following five typical routing metrics: end-to-end delay, number of hops, expected transmission count(ETX),node remaining energy, and child node ***, IAR-TMO uses triangle module operator to fuse membership functions of these routing metrics. Then, IAR-TMO selects preferred parents(the next hop) based on the triangle module operator. Theoretical analysis and simulation results show that IAR-TMO has a great improvement when compared with two recent representative algorithms: ETXOF(ETX Objective function) and OF-FL(Objective function based on Fuzzy Logic), in terms of network lifetime, average end-to-end delay,etc. Consequently, the network performances of AMI networks can be improved effectively.

关键词： routing protocol RPL triangle module operator membership function objective function

Fuzzy working state evaluating function and its algorithm for analogue circuits

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The Journal of China Universities of Posts and Telecommunications 2015年第1期22卷 83-88页

作者： Huang Liang Song Wei School of Electronic and Information Engineering Beijing Jiaotong University School of Information Engineering Minzu University of China

The working state （WS） evaluation is a valuable task in the process of failure diagnosis in the analogue circuits. A fuzzy evaluating algorithm was proposed to quantify the working condition of analogue circuit regarded as fuzzy system. Several familiar WS evaluating functions based on fuzzy membership functions were also proposed to calculate the local working state indexes （WSI） of each node in an analogue circuit. The decision function combined with the WS evaluating functions is used to synthesize all the local WSI to the global WSI of the whole circuit. An example was presented to verify that the working status of the analogue circuits can be described by the new WS evaluating algorithm and the global WSI objectively and accurately.

关键词： analogue circuit working state fuzzy theory membership function

A New Approach for Solving Fuzzy Linear Multi-Criterion Problems: An Approach Based on Minimization of the Errors functions

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American Journal of Operations Research 2023年第1期13卷 1-17页

作者： Joél Lema Makubikua Amani Wema Yves Tinda Mangongo Joseph-Désiré Kyemba Bukweli Justin Dupar Busili Kampempe Département des Mathématiques et Informatique Université de Kinshasa Kinshasa The Democratic Republic of the Congo Conférence Congolaise de Recherche en Informatique et en Mathématiques Appliquées COCORIMA Kinshasa The Democratic Republic of the Congo

The main purpose of this paper is to build a new approach for solving a fuzzy linear multi-criterion problem by defining a function called “error function”. For this end, the concept of level set is used to construct the error function. In addition, we introduce the concept of deviation variable in the definition of the error function. The algorithm of the new approach is summarized in three main steps: first, we transform the original fuzzy problem into a deterministic one by choosing a specific level . second, we solve separately each uni-criteria problem and we compute the error function for each criteria. Finally, we minimize the sum of error functions in order to obtain the desired compromise solution. A numerical example is done for a comparative study with some existing approaches to show the effectiveness of the new approach.

关键词： Deviation Variable Compromise Solution membership function Error function Decision-Making function

Optimum path planning of mobile robot in unknown static and dynamic environments using Fuzzy-Wind Driven Optimization algorithm

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Defence Technology（防务技术） 2017年第1期13卷 47-58页

作者： Anish Pandey Dayal R.Parhi Mechanical Engineering Department N.I.T.RourkelaOrissaIndia

This article introduces a singleton type-1 fuzzy logic system(T1-SFLS) controller and Fuzzy-WDO hybrid for the autonomous mobile robot navigation and collision avoidance in an unknown static and dynamic environment. The WDO(Wind Driven Optimization) algorithm is used to optimize and tune the input/output membership function parameters of the fuzzy controller. The WDO algorithm is working based on the atmospheric motion of infinitesimal small air parcels navigates over an N-dimensional search domain. The performance of this proposed technique has compared through many computer simulations and real-time experiments by using Khepera-Ⅲ mobile robot. As compared to the T1-SFLS controller the Fuzzy-WDO algorithm is found good agreement for mobile robot navigation.

关键词： Singleton type-1 fuzzy Navigation Wind driven optimization membership function Atmospheric motion

New Time-varying Fuzzy Sets Based on a PSO Midpoint of the Universe of Discourse

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International Journal of Automation and computing 2016年第4期13卷 392-400页

作者： Salim Ziani Automatic and Robotics Laboratory Department of Electronics University of Constantine 1 Constantine 25000 Algeria

The paper presents a robust parallel distributed compensation （PDC） fuzzy controller for a nonlinear and certain system in continuous time described by the Tal^gi-Sugeno （T-S） fuzzy model. This controller is based on a new type of time-varying fuzzy sets （TVFS）. These fuzzy sets are characterized by displacement of the kernels to the right or left of the universe of discourse, and they are directed by a well-defined criterion. In this work, we only focused on the movement of midpoint of the universe. The movements of this midpoint are optimized by particle swarm optimization （PSO） approach.

关键词： Fuzzy sets fuzzy system membership function parallel distributed compensation (PDC) fuzzy controller particle swarmoptimization (PSO) approach linear matrix inequality (LMI).

A Modification to the Fuzzy Regression Discontinuity Model to Settings with Fuzzy Variables

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Open Journal of Statistics 2022年第5期12卷 676-690页

作者： Portia Kuzivakwashe Mafukidze Samuel Musili Mwalili Thomas Mageto Department of Mathematics The Pan African University Institute for Basic Sciences Technology and Innovation (PAUSTI) Nairobi Kenya Department of Statistics and Actuarial Sciences Jomo Kenyatta University of Agriculture and Technology Nairobi Kenya

Despite the fact that fuzzy regression discontinuity designs are growing in popularity, a lot of research takes into account treatment non-compliance difficulties, specifically the fuzziness of the treatment impact. This paper took into account independent and dependent fuzzy factors when creating these designs. Additionally we took into account treatment non-compliance difficulties, specifically the fuzziness of the treatment impact, as other research does. The modified Fuzzy Regression Discontinuity model is preferable for modeling fuzzy data. It enables us to draw improved causal effects accommodating fuzzy variables, not just the fuzziness of the treatment effect as in Fuzzy Regression Discontinuity models. A fuzzy dataset is converted into crisp data by the Centroid method of defuzzification. Once the data is crisp, the traditional least squares methods of approximation are used to estimate the parameters in the model since these parameters are considered crisp whilst the error terms are fuzzy. The Alcohol Use Disorders Identification Test score(AUDIT score) can be used as a cutoff to initiate treatment in this case and can be used to predict the progression of HIV disease and/or AIDS. Counseling helps to lower the use of alcohol in people living with HIV/AIDS (PLWHA) as a result, improving the participants’ CD4 counts.

关键词： Fuzzy Regression Discontinuity Fuzzification Centroid Method of Defuzzification membership function