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1 – 9 of 9
Article
Publication date: 1 February 2013

Moêz Soltani and Abdelkader Chaari

The purpose of this paper is to present a new methodology for identification of the parameters of the local linear Takagi‐Sugeno fuzzy models using weighted recursive least…

Abstract

Purpose

The purpose of this paper is to present a new methodology for identification of the parameters of the local linear Takagi‐Sugeno fuzzy models using weighted recursive least squares. The weighted recursive least squares (WRLS) is sensitive to initialization which leads to no converge. In order to overcome this problem, Euclidean particle swarm optimization (EPSO) is employed to optimize the initial states of WRLS. Finally, validation results are given to demonstrate the effectiveness and accuracy of the proposed algorithm. A comparative study is presented. Validation results involving simulations of numerical examples and the liquid level process have demonstrated the practicality of the algorithm.

Design/methodology/approach

A new method for nonlinear system modelling. The proposed algorithm is employed to optimize the initial states of WRLS algorithm in two phases of learning algorithm.

Findings

The results obtained using this novel approach were comparable with other modeling approaches reported in the literature. The proposed algorithm is able to handle various types of modeling problems with high accuracy.

Originality/value

In this paper, a new method is employed to optimize the initial states of WRLS algorithm in two phases of the learning algorithm.

Article
Publication date: 3 November 2014

Adel Taeib, Moêz Soltani and Abdelkader Chaari

The purpose of this paper is to propose a new type of predictive fuzzy controller. The desired nonlinear system behavior is described by a set of Takagi-Sugeno (T-S) model

Abstract

Purpose

The purpose of this paper is to propose a new type of predictive fuzzy controller. The desired nonlinear system behavior is described by a set of Takagi-Sugeno (T-S) model. However, due to the complexity of the real processes, obtaining a high quality control with a short settle time, a periodical step response and zero steady-state error is often a difficult task. Indeed, conventional model predictive control (MPC) attempts to minimize a quadratic cost over an extended control horizon. Then, the MPC is insufficient to adapt to changes in system dynamics which have characteristics of complex constraints. In addition, it is shown that the clustering algorithm is sensitive to random initialization and may affect the quality of obtaining predictive fuzzy controller. In order to overcome these problems, chaos particle swarm optimization (CPSO) is used to perform model predictive controller for nonlinear process with constraints. The practicality and effectiveness of the identification and control scheme is demonstrated by simulation results involving simulations of a continuous stirred-tank reactor.

Design/methodology/approach

A new type of predictive fuzzy controller. The proposed algorithm based on CPSO is used to perform model predictive controller for nonlinear process with constraints.

Findings

The results obtained using this the approach were comparable with other modeling approaches reported in the literature. The proposed control scheme has been show favorable results either in the absence or in the presence of disturbance compared with the other techniques. It confirms the usefulness and robustness of the proposed controller.

Originality/value

This paper presents an intelligent model predictive controller MPC based on CPSO (MPC-CPSO) for T-S fuzzy modeling with constraints.

Details

Kybernetes, vol. 43 no. 9/10
Type: Research Article
ISSN: 0368-492X

Keywords

Article
Publication date: 12 June 2017

Shabia Shabir Khan and S.M.K. Quadri

As far as the treatment of most complex issues in the design is concerned, approaches based on classical artificial intelligence are inferior compared to the ones based on…

Abstract

Purpose

As far as the treatment of most complex issues in the design is concerned, approaches based on classical artificial intelligence are inferior compared to the ones based on computational intelligence, particularly this involves dealing with vagueness, multi-objectivity and good amount of possible solutions. In practical applications, computational techniques have given best results and the research in this field is continuously growing. The purpose of this paper is to search for a general and effective intelligent tool for prediction of patient survival after surgery. The present study involves the construction of such intelligent computational models using different configurations, including data partitioning techniques that have been experimentally evaluated by applying them over realistic medical data set for the prediction of survival in pancreatic cancer patients.

Design/methodology/approach

On the basis of the experiments and research performed over the data belonging to various fields using different intelligent tools, the authors infer that combining or integrating the qualification aspects of fuzzy inference system and quantification aspects of artificial neural network can prove an efficient and better model for prediction. The authors have constructed three soft computing-based adaptive neuro-fuzzy inference system (ANFIS) models with different configurations and data partitioning techniques with an aim to search capable predictive tools that could deal with nonlinear and complex data. After evaluating the models over three shuffles of data (training set, test set and full set), the performances were compared in order to find the best design for prediction of patient survival after surgery. The construction and implementation of models have been performed using MATLAB simulator.

Findings

On applying the hybrid intelligent neuro-fuzzy models with different configurations, the authors were able to find its advantage in predicting the survival of patients with pancreatic cancer. Experimental results and comparison between the constructed models conclude that ANFIS with Fuzzy C-means (FCM) partitioning model provides better accuracy in predicting the class with lowest mean square error (MSE) value. Apart from MSE value, other evaluation measure values for FCM partitioning prove to be better than the rest of the models. Therefore, the results demonstrate that the model can be applied to other biomedicine and engineering fields dealing with different complex issues related to imprecision and uncertainty.

Originality/value

The originality of paper includes framework showing two-way flow for fuzzy system construction which is further used by the authors in designing the three simulation models with different configurations, including the partitioning methods for prediction of patient survival after surgery. Several experiments were carried out using different shuffles of data to validate the parameters of the model. The performances of the models were compared using various evaluation measures such as MSE.

Details

International Journal of Intelligent Computing and Cybernetics, vol. 10 no. 2
Type: Research Article
ISSN: 1756-378X

Keywords

Article
Publication date: 12 June 2017

Amira Aydi, Mohamed Djemel and Mohamed Chtourou

The purpose of this paper is to use the internal model control to deal with nonlinear stable systems affected by parametric uncertainties.

Abstract

Purpose

The purpose of this paper is to use the internal model control to deal with nonlinear stable systems affected by parametric uncertainties.

Design/methodology/approach

The dynamics of a considered system are approximated by a Takagi-Sugeno fuzzy model. The parameters of the fuzzy rules premises are determined manually. However, the parameters of the fuzzy rules conclusions are updated using the descent gradient method under inequality constraints in order to ensure the stability of each local model. In fact, without making these constraints the training algorithm can procure one or several unstable local models even if the desired accuracy in the training step is achieved. The considered robust control approach is the internal model. It is synthesized based on the Takagi-Sugeno fuzzy model. Two control strategies are considered. The first one is based on the parallel distribution compensation principle. It consists in associating an internal model control for each local model. However, for the second strategy, the control law is computed based on the global Takagi-Sugeno fuzzy model.

Findings

According to the simulation results, the stability of all local models is obtained and the proposed fuzzy internal model control approaches ensure robustness against parametric uncertainties.

Originality/value

This paper introduces a method for the identification of fuzzy model parameters ensuring the stability of all local models. Using the resulting fuzzy model, two fuzzy internal model control designs are presented.

Details

International Journal of Intelligent Computing and Cybernetics, vol. 10 no. 2
Type: Research Article
ISSN: 1756-378X

Keywords

Article
Publication date: 26 June 2019

Nguyen Ngoc Son, Cao Van Kien and Ho Pham Huy Anh

This paper aims to propose an advanced tracking control of the uncertain nonlinear dynamic system using a novel hybrid fuzzy linear quadratic regulator…

151

Abstract

Purpose

This paper aims to propose an advanced tracking control of the uncertain nonlinear dynamic system using a novel hybrid fuzzy linear quadratic regulator (LQR)-proportional-integral-derivative (PID) sliding mode control (SMC) optimized by differential evolution (DE) algorithm.

Design/methodology/approach

First, a swing-up and balancing control is presented for an experimental uncertain nonlinear Pendubot system perturbed with friction. The DE-based optimal SMC scheme is used to optimally swing up the Pendubot system to the top equilibrium position. Then the novel hybrid fuzzy-based on LQR fusion function and PID controller optimized by DE algorithm is innovatively applied for balancing and control the position of the first link of the Pendubot in the down-right position with tracking sinusoidal signal reference.

Findings

Experimental results demonstrate the robustness and effectiveness of the proposed approach in balancing control for an uncertain nonlinear Pendubot system perturbed with internal friction.

Originality/value

This manuscript is an original research paper and has never been submitted to any other journal.

Book part
Publication date: 1 October 2015

Ikseon Suh and Joseph Ugrin

This study investigates how disclosure of the board of directors’ leadership and role in risk oversight (BODs oversight disclosure) influences investors’ judgments when…

Abstract

This study investigates how disclosure of the board of directors’ leadership and role in risk oversight (BODs oversight disclosure) influences investors’ judgments when information on risk exposures is disclosed. The theoretical lens through which we examine this issue involves negativity bias. Sixty-two stock market investors who engage in the evaluation and/or investment of stocks on a regular or professional basis participated in our study. Our results reveal that the addition of BODs oversight disclosure (positive information) does not carry significant weight on investor judgments (i.e., attractiveness and investment) when financial statement disclosures indicate a high level of operational and financial risk exposures (negative information). In contrast, under the condition of a low level of risk exposures, BODs oversight disclosure causes investors to assess higher risk in terms of worry, catastrophic potentials and unfamiliarity about risk information and, in turn, make less favorable investor judgments. Our findings add to the literature on negativity bias and contribute to the debate on the usefulness of disclosures about risk.

Details

Advances in Accounting Behavioral Research
Type: Book
ISBN: 978-1-78441-635-5

Keywords

Article
Publication date: 3 September 2021

Majid Kalantary and Reza Farzipoor Saen

This paper discusses how learning-by-doing (LBD) criterion can be used to evaluate the sustainability of supply chains. This paper assesses the impacts of teamwork on the LBD…

Abstract

Purpose

This paper discusses how learning-by-doing (LBD) criterion can be used to evaluate the sustainability of supply chains. This paper assesses the impacts of teamwork on the LBD criterion. Besides, the effect of the internship of new labors on the LBD criterion is discussed.

Design/methodology/approach

The repeat of a task leads to a gradual improvement in the efficiency of production systems. LBD occurs by accumulating knowledge and skills in multiple periods. LBD can be used to study changes in the efficiency. Efficiency can be improved by accumulating knowledge and skills. In this paper, the LBD criterion is projected on learning curve (LC) models. Furthermore, the LC models are fitted to the supply chains. Each supply chain may have a unique LC model. A minimum difference is set between the current performance of decision making unit (DMU) and the estimated performance of DMU based on DMU's LC. Hence, a point in which the LBD occurs is determined.

Findings

This paper develops an inverse network dynamic data envelopment analysis (DEA) model to assess the sustainability of supply chains DMUs. Findings imply that the LBD criterion plays an important role in assessing the sustainability of supply chains. Furthermore, managers should increase the internships and teamwork to get more benefit from the LBD criterion.

Originality/value

For the first time, this paper uses the LBD criterion to assess the sustainability of supply chains given the LC equations.

Article
Publication date: 19 August 2019

Kuo-Ping Lin, Chun-Min Yu and Kuen-Suan Chen

The purpose of this paper is to establish mechanisms for process improvement so that production efficiency and product quality can be expected, and create a sustainable…

Abstract

Purpose

The purpose of this paper is to establish mechanisms for process improvement so that production efficiency and product quality can be expected, and create a sustainable development in terms of circular economy.

Design/methodology/approach

The authors obtain a critical value from statistical hypothesis testing, and thereby construct a process capability indices chart, which both lowers the chance of quality level misjudgment caused by sampling error and provides reference for the processes improvement in poor quality levels. The authors used the bottom bracket of bicycles as an example to demonstrate the model and methods proposed in this study.

Findings

This approach enables us to plot multiple quality characteristics, despite varying attributes and specifications, onto the same process capability analysis chart. And it therefore increases accuracy and precision to reduce rework and scrap rates (reduce), increase product availability, reduce maintenance frequency and increase reuse (reuse), increase the recycle rates of components (recycle) and lengthen service life, which will delay recovery time (recovery).

Originality/value

Parts manufacturers in the industry chain can upload their production data to the cloud platform. The quality control center of the bicycle manufacturer can utilized the production data analysis model to identify critical-to-quality characteristics. The platform also offers reference for improvement and adds the improvement achievements and experience to its knowledge management to provide the entire industry chain. Feedback is also given to the R&D department of the bicycle manufacturer as reference for more robust product designs, more reasonable tolerance designs, and selection criteria for better parts suppliers, thereby forming an intelligent manufacturing loop system.

Details

Industrial Management & Data Systems, vol. 119 no. 8
Type: Research Article
ISSN: 0263-5577

Keywords

Article
Publication date: 13 August 2024

Md Jahidur Rahman, Hongtao Zhu and Li Yue

This study aims to examine whether the adoption of artificial intelligence (AI) by audit firms and their clients affects audit efficiency and audit quality.

Abstract

Purpose

This study aims to examine whether the adoption of artificial intelligence (AI) by audit firms and their clients affects audit efficiency and audit quality.

Design/methodology/approach

This study empirically examines the abovementioned research question based on data from China for the years 2011 to 2020. It uses audit report lag as a proxy for audit efficiency and the likelihood of annual report restatement as a proxy for audit quality. It adopts the propensity score matching and the two-stage OLS regression model to address the endogeneity issue led by firms’ innate complicated functions.

Findings

The findings show that when audit firms and their clients use AI separately, there's a positive link between AI use and audit report lag. However, when audit firms and clients use AI together, there's a negative link between AI use and audit report delays that enhance overall audit efficiency. Next, the authors observe a negative link between AI use and the likelihood of a restatement. Finally, the authors find that the association between AI adoption and audit quality is driven by increased audit effort lag. Results are consistent and robust to endogeneity tests and sensitivity analyses.

Originality/value

Findings can complement the audit quality and corporate governance literature by clarifying that external audit must evolve through digitalization and the incorporation of newly developed digital tools, such as AI.

Details

Managerial Auditing Journal, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0268-6902

Keywords

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