Evolved auxiliary controller with applications to aerospace

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Tim Chen ◽  
N. Kapronand ◽  
C.Y. Hsieh ◽  
J. Cy Chen
Keyword(s):  
Asymptotic Stability ◽  
High Speed ◽  
Bat Algorithm ◽  
Parabolic Partial Differential Equation ◽  
Linear Matrix ◽  
Rule Base ◽  
Aerospace Vehicles ◽  
Content Type ◽  
Fuzzy Neural ◽  
Linear Differential

Purpose To guarantee the asymptotic stability of discrete-time nonlinear systems, this paper aims to propose an evolved bat algorithm fuzzy neural network (NN) controller algorithm. Design/methodology/approach In evolved fuzzy NN modeling, the NN model and linear differential inclusion representation are established for the arbitrary nonlinear dynamics. The control problems of the Fisher equation and a temperature cooling fin for high-speed aerospace vehicles will be described and demonstrated. The signal auxiliary controlled system is represented for the nonlinear parabolic partial differential equation (PDE) systems and the criterion of stability is derived via the Lyapunov function in terms of linear matrix inequalities. Findings This representation is constructed by sector nonlinearity, which converts the nonlinear model to a multiple rule base for the linear model and a new sufficient condition to guarantee the asymptotic stability. Originality/value This study also injects high frequency as an auxiliary and the control performance to stabilize the nonlinear high-speed aerospace vehicle system.

Evolved Fuzzy NN Control for Discrete-Time Nonlinear Systems

2019 ◽  
Vol 29 (01) ◽  
pp. 2050015 ◽  
Author(s):  
Tim Chen ◽  
A. Babanin ◽  
Assim Muhammad ◽  
B. Chapron ◽  
C. Y. J. Chen
Keyword(s):  
Nonlinear Systems ◽  
Asymptotic Stability ◽  
Discrete Time ◽  
Fuzzy Neural Network ◽  
Bat Algorithm ◽  
Linear Matrix ◽  
Rule Base ◽  
Sufficiency Condition ◽  
Fuzzy Neural ◽  
Linear Differential

To guarantee the asymptotic stability of discrete-time nonlinear systems, this paper proposes an Evolved Bat Algorithm (EBA) fuzzy neural network (NN) controller. In the evolved fuzzy NN modeling, an NN model and linear differential inclusion (LDI) representation are established for arbitrary nonlinear dynamics. This representation is constructed by the use of sector nonlinearity to convert a nonlinear model to the multiple rule base of the linear model, and a new sufficiency condition to guarantee asymptotic stability in the Lyapunov function is implemented in terms of linear matrix inequalities. The proposed method is an enhancement of existing methods which produces good results.

Intelligent fuzzy algorithm for nonlinear discrete-time systems

2019 ◽  
Vol 42 (7) ◽  
pp. 1358-1374
Author(s):  
Tim Chen ◽  
CYJ Chen
Keyword(s):  
Large Scale ◽  
Optimal Solution ◽  
Bat Algorithm ◽  
Linear Matrix ◽  
Neural Network Modeling ◽  
Rule Base ◽  
Large Scale System ◽  
Model Based ◽  
Linear Differential ◽  
The Stability

This paper is concerned with the stability analysis and the synthesis of model-based fuzzy controllers for a nonlinear large-scale system. In evolved fuzzy NN (neural network) modeling, the NN model and LDI (linear differential inclusion) representation are established for the arbitrary nonlinear dynamics. The evolved bat algorithm (EBA) is first incorporated in the controlled algorithm of stability conditions, which could rapidly find the optimal solution and raise the control performance. This representation is constructed by taking advantage of sector nonlinearity that converts the nonlinear model to a multiple rule base linear model. A new sufficient condition guaranteeing asymptotic stability is implemented via the Lyapunov function in terms of linear matrix inequalities. Subsequently, based on this criterion and the decentralized control scheme, an evolved model-based fuzzy H infinity set is synthesized to stabilize the nonlinear large-scale system. Finally, a numerical example and simulation is given to illustrate the results.

scholarly journals Stability Conditions for Fuzzy Neural Networks

2012 ◽  
Vol 2012 ◽  
pp. 1-4
Author(s):  
Choon Ki Ahn
Keyword(s):  
Neural Networks ◽  
Asymptotic Stability ◽  
Fuzzy Neural Networks ◽  
External Input ◽  
Linear Matrix ◽  
Stability Conditions ◽  
Matrix Inequality ◽  
Novel Approach ◽  
Fuzzy Neural ◽  
The Stability

This paper presents a novel approach to assess the stability of fuzzy neural networks. First, we propose a new condition for the stability of fuzzy neural networks. Second, a new stability condition based on linear matrix inequality (LMI) is presented for fuzzy neural networks. These conditions also ensure asymptotic stability without external input.

Influence of ageing treatment on microstructure, mechanical properties and adhesive wear behaviour of 6063 aluminium alloy

2014 ◽  
Vol 66 (4) ◽  
pp. 520-524 ◽  
Author(s):  
Serkan Büyükdoğan ◽  
Süleyman Gündüz ◽  
Mustafa Türkmen
Keyword(s):  
Mechanical Properties ◽  
Wear Resistance ◽  
High Speed ◽  
Al Alloys ◽  
Wear Behaviour ◽  
Al Alloy ◽  
Strain Ageing ◽  
Content Type ◽  
Static Strain ◽  
Structural Applications

Purpose – The paper aims to provide new observations about static strain ageing in aluminium (Al) alloys which are widely used in structural applications. Design/methodology/approach – The present work aims to provide theoretical and practical information to industries or researchers who may be interested in the effect of static strain ageing on mechanical properties of Al alloys. The data are sorted into the following sections: introduction, materials and experimental procedure, results and discussion and conclusions. Findings – Tensile strength, proof strength (0.2 per cent) and percentage elongation measurement were used to investigate the effect of strain ageing on the mechanical properties. Wear tests were performed by sliding the pin specimens, which were prepared from as-received, solution heat-treated, deformed and undeformed specimens after ageing, on high-speed tool steel (64 HRC). It is concluded that the variations in ageing time improved the strength and wear resistance of the 6063 Al alloy; however, a plastically deformed solution-treated alloy has higher strength and wear resistance than undeformed specimens for different ageing times at 180°C. Practical implications – A very useful source of information for industries using or planning to produce Al alloys. Originality/value – This paper fulfils an identified resource need and offers practical help to the industries.

Impacts of high-speed railway on the industrial pollution emissions in China

Kybernetes ◽  
2020 ◽  
Vol 49 (11) ◽  
pp. 2713-2735 ◽  
Author(s):  
Xiaomin Fan ◽  
Yingzhi Xu ◽  
Yongqing Nan ◽  
Baoli Li ◽  
Haiya Cai
Keyword(s):  
Environmental Effects ◽  
Industrial Pollution ◽  
High Speed ◽  
Assessment Method ◽  
Economic Effects ◽  
High Speed Railway ◽  
Central Cities ◽  
Content Type ◽  
Pollution Emissions ◽  
The Impact

Purpose The purpose of this paper is to analyse the impact of high-speed railway (HSR) on industrial pollution emissions using the data for 285 prefecture-level cities in China from 2004 to 2016. Design/methodology/approach The research method used in this paper is the multi-period difference-in-differences (DID) model, which is an effective policy effect assessment method. To further address the issue of endogeneity, the DID integrated with the propensity score matching (PSM-DID) approach is employed to eliminate the potential self-selection bias. Findings The results show that the HSR has significantly reduced industrial pollution emissions, which is validated by several robustness tests. Compared with peripheral cities, HSR exerts a greater impact on industrial pollution emissions in central cities. In addition, the mechanism test reveals that the optimised allocation of inter-city industries is an important channel for HSR to mitigate industrial pollution emissions, and this is closely related to the location of HSR stations. Originality/value Previous studies have paid more attention to evaluating the economic effects of HSR, however, most of these studies overlook its environmental effects. Consequently, the impact of HSR on industrial pollution emissions is led by using multi-period DID models in this paper, in which the environmental effects are measured. The results of this paper can provide a reference for the pollution reduction policies and also the coordinated development of economic growth and environmental quality.

Comparison of the reluctance laminated and solid rotor synchronous machine operating at high temperatures

2019 ◽  
Vol 38 (4) ◽  
pp. 1111-1119 ◽  
Author(s):  
Marcin Lefik ◽  
Krzysztof Komeza ◽  
Ewa Napieralska-Juszczak ◽  
Daniel Roger ◽  
Piotr Andrzej Napieralski
Keyword(s):  
High Speed ◽  
Design Methodology ◽  
Three Dimensional ◽  
Synchronous Machine ◽  
Point Of View ◽  
Heat Sources ◽  
Model Calculations ◽  
Content Type ◽  
Thermal Phenomenon ◽  
Practical Implications

Purpose The purpose of this paper is to present a comparison between reluctance synchronous machine-enabling work at high internal temperature (HT° machine) with laminated and solid rotor. Design/methodology/approach To obtain heat sources for the thermal model, calculations of the electromagnetic field were made using the Opera 3D program including effect of rotation and the resulting eddy current losses. To analyse the thermal phenomenon, the 3D coupled thermal-fluid (CFD) model is used. Findings The presented results show clearly that laminated construction is much better from a point of view of efficiency and temperature. However, solid construction can be interesting for high speed machines due to their mechanical robustness. Research limitations/implications The main problem, despite the use of parallel calculations, is the long calculation time. Practical implications The obtained simulation and experimental results show the possibility of building a machine operating at a much higher ambient temperature than it was previously produced for example in the vicinity of the aircraft turbines. Originality/value The paper presents the application of fully three-dimensional coupled electromagnetic and thermal analysis of new machine constructions designed for elevated temperature.

Characteristic properties of AlTiN and TiN coated HSS materials

2015 ◽  
Vol 67 (2) ◽  
pp. 172-180 ◽  
Author(s):  
Mumin Sahin ◽  
Cenk Misirli ◽  
Dervis Özkan
Keyword(s):  
Surface Roughness ◽  
Tensile Strength ◽  
High Speed ◽  
Cutting Tools ◽  
High Speed Steel ◽  
Wear Properties ◽  
Content Type ◽  
X Ray ◽  
Number Of Cycles ◽  
Future Work

Purpose – The purpose of this paper is to examine mechanical and metallurgical properties of AlTiN- and TiN-coates high-speed steel (HSS) materials in detail. Design/methodology/approach – In this study, HSS steel parts have been processed through machining and have been coated with AlTiN and TiN on physical vapour deposition workbench at approximately 6,500°C for 4 hours. Tensile strength, fatigue strength, hardness tests for AlTiN- and TiN-coated HSS samples have been performed; moreover, energy dispersive X-ray spectroscopy and X-ray diffraction analysis and microstructure analysis have been made by scanning electron microscopy. The obtained results have been compared with uncoated HSS components. Findings – It was found that tensile strength of TiAlN- and TiN-coated HSS parts is higher than that of uncoated HSS parts. Highest tensile strength has been obtained from TiN-coated HSS parts. Number of cycles for failure of TiAlN- and TiN-coated HSS parts is higher than that for HSS parts. Particularly TiN-coated HSS parts have the most valuable fatigue results. However, surface roughness of fatigue samples may cause notch effect. For this reason, surface roughness of coated HSS parts is compared with that of uncoated ones. While the average surface roughness (Ra) of the uncoated samples was in the range of 0.40 μm, that of the AlTiN- and TiN-coated samples was in the range of 0.60 and 0.80 μm, respectively. Research limitations/implications – It would be interesting to search different coatings for cutting tools. It could be the good idea for future work to concentrate on wear properties of tool materials. Practical implications – The detailed mechanical and metallurgical results can be used to assess the AlTiN and TiN coating applications in HSS materials. Originality/value – This paper provides information on mechanical and metallurgical behaviour of AlTiN- and TiN-coated HSS materials and offers practical help for researchers and scientists working in the coating area.

scholarly journals Knowledge-based Lean Six Sigma maintenance system for sustainable buildings

2017 ◽  
Vol 8 (1) ◽  
pp. 109-130 ◽  
Author(s):  
Jasim Aldairi ◽  
M.K. Khan ◽  
J. Eduardo Munive-Hernandez
Keyword(s):  
Conceptual Framework ◽  
Six Sigma ◽  
Research Work ◽  
Lean Six Sigma ◽  
Rule Base ◽  
Sustainable Buildings ◽  
Sustainable Building ◽  
Content Type ◽  
Environmentally Sustainable ◽  
Knowledge Based

Purpose This paper aims to develop a knowledge-based (KB) system for Lean Six Sigma (LSS) maintenance in environmentally sustainable buildings (Lean6-SBM). Design/methodology/approach The Lean6-SBM conceptual framework has been developed using the rule base approach of KB system and joint integration with gauge absence prerequisites (GAP) technique. A comprehensive literature review is given for the main pillars of the framework with a typical output of GAP analysis. Findings Implementation of LSS in the sustainable building maintenance context requires a pre-assessment of the organisation’s capabilities. A conceptual framework with a design structure is proposed to tackle this issue with the provision of an enhancing strategic and operational decision-making hierarchy. Research limitations/implications Future research work might consider validating this framework in other type of industries. Practical implications Maintenance activities in environmentally sustainable buildings must take prodigious standards into consideration, and, therefore, a robust quality assurance measure has to be integrated. Originality/value The significance of this research is to present a novel use of hybrid KB/GAP methodologies to develop a Lean6-SBM system. The originality and novelty of this approach will assist in identifying quality perspectives while implementing different maintenance strategies in the sustainable building context.

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