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Article
Publication date: 29 July 2014

M.Q. Chau, X. Han, C. Jiang, Y.C. Bai, T.N. Tran and V.H. Truong

The performance measure approach (PMA) is widely adopted for reliability analysis and reliability-based design optimization because of its robustness and efficiency compared to…

335

Abstract

Purpose

The performance measure approach (PMA) is widely adopted for reliability analysis and reliability-based design optimization because of its robustness and efficiency compared to reliability index approach. However, it has been reported that PMA involves repeat evaluations of probabilistic constraints therefore it is prohibitively expensive for many large-scale applications. In order to overcome these disadvantages, the purpose of this paper is to propose an efficient PMA-based reliability analysis technique using radial basis function (RBF).

Design/methodology/approach

The RBF is adopted to approximate the implicit limit state functions in combination with latin hypercube sampling (LHS) strategy. The advanced mean value method is applied to obtain the most probable point (MPP) with the prescribed target reliability and corresponding probabilistic performance measure to improve analysis accuracy. A sequential framework is proposed to relocate the sampling center to the obtained MPP and reconstruct RBF until a criteria is satisfied.

Findings

The method is shown to be better in the computation time to the PMA based on the actual model. The analysis results of probabilistic performance measure are accurately close to the reference solution. Five numerical examples are presented to demonstrate the effectiveness of the proposed method.

Originality/value

The main contribution of this paper is to propose a new reliability analysis technique using reconstructed RBF approximate model. The originalities of this paper may lie in: investigating the PMA using metamodel techniques, using RBF instead of the other types of metamodels to deal with the low efficiency problem.

Details

Engineering Computations, vol. 31 no. 6
Type: Research Article
ISSN: 0264-4401

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Article
Publication date: 30 October 2023

Qiangqiang Zhai, Zhao Liu, Zhouzhou Song and Ping Zhu

Kriging surrogate model has demonstrated a powerful ability to be applied to a variety of engineering challenges by emulating time-consuming simulations. However, when it comes to…

111

Abstract

Purpose

Kriging surrogate model has demonstrated a powerful ability to be applied to a variety of engineering challenges by emulating time-consuming simulations. However, when it comes to problems with high-dimensional input variables, it may be difficult to obtain a model with high accuracy and efficiency due to the curse of dimensionality. To meet this challenge, an improved high-dimensional Kriging modeling method based on maximal information coefficient (MIC) is developed in this work.

Design/methodology/approach

The hyperparameter domain is first derived and the dataset of hyperparameter and likelihood function is collected by Latin Hypercube Sampling. MIC values are innovatively calculated from the dataset and used as prior knowledge for optimizing hyperparameters. Then, an auxiliary parameter is introduced to establish the relationship between MIC values and hyperparameters. Next, the hyperparameters are obtained by transforming the optimized auxiliary parameter. Finally, to further improve the modeling accuracy, a novel local optimization step is performed to discover more suitable hyperparameters.

Findings

The proposed method is then applied to five representative mathematical functions with dimensions ranging from 20 to 100 and an engineering case with 30 design variables.

Originality/value

The results show that the proposed high-dimensional Kriging modeling method can obtain more accurate results than the other three methods, and it has an acceptable modeling efficiency. Moreover, the proposed method is also suitable for high-dimensional problems with limited sample points.

Details

Engineering Computations, vol. 40 no. 9/10
Type: Research Article
ISSN: 0264-4401

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Article
Publication date: 16 April 2018

Naser Safaeian Hamzehkolaei, Mahmoud Miri and Mohsen Rashki

Reliability-based design optimizations (RBDOs) of engineering structures involve complex non-linear/non-differentiable performance functions, including both continuous and…

149

Abstract

Purpose

Reliability-based design optimizations (RBDOs) of engineering structures involve complex non-linear/non-differentiable performance functions, including both continuous and discrete variables. The gradient-based RBDO algorithms are less than satisfactory for these cases. The simulation-based approaches could also be computationally inefficient, especially when the double-loop strategy is used. This paper aims to present a pseudo-double loop flexible RBDO, which is efficient for solving problems, including both discrete/continuous variables.

Design/methodology/approach

The method is based on the hybrid improved binary bat algorithm (BBA) and weighed simulation method (WSM). According to this method, each BBA’s movement generates proper candidate solutions, and subsequently, WSM evaluates the reliability levels for design candidates to conduct swarm in a low-cost safe-region.

Findings

The accuracy of the proposed enhanced BBA and also the hybrid WSM-BBA are examined for ten benchmark deterministic optimizations and also four RBDO problems of truss structures, respectively. The solved examples reveal computational efficiency and superiority of the method to conventional RBDO approaches for solving complex problems including discrete variables.

Originality/value

Unlike other RBDO approaches, the proposed method is such organized that only one simulation run suffices during the optimization process. The flexibility future of the proposed RBDO framework enables a designer to present multi-level design solutions for different arrangements of the problem by using the results of the only one simulation for WSM, which is very helpful to decrease computational burden of the RBDO. In addition, a new suitable transfer function that enhanced convergence rate and search ability of the original BBA is introduced.

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Article
Publication date: 10 March 2022

Nitika Sharma, Arminda Paço and Pradeep Kautish

This study intends to contribute to the literature of eco-innovation by examining the pro-environmental intentions and behaviour among consumers through their understanding of…

2823

Abstract

Purpose

This study intends to contribute to the literature of eco-innovation by examining the pro-environmental intentions and behaviour among consumers through their understanding of eco-innovation. Thus, the relationship among eco-innovation, general pro-social attitude, generativity, environmental concern, purchasing intentions and buying environmentally friendly products and the differences of the relationship between high and low emotional loyalty and Generation Y and Z were investigated via structural equation modelling (SEM).

Design/methodology/approach

Data were collected through an online questionnaire directed to Indian consumers, and analysis was done through partial least square structural equation modelling (PLS-SEM) in two stages, i.e. measurement model and structural model.

Findings

Results confirm the relationships established in the proposed model, and some differences were found between the levels of emotional loyalty and the Generations Y and Z. The research shows that individualistic norms and perceived marketplace influence play a purposeful role in transforming environmental concerns into buying behaviour towards eco-innovation-driven products.

Practical implications

From a policy and management perspective, the results not only imply the importance of continuous performance and environmental improvement but also those policies hindering diffusion and adoption need to be addressed. Green buying is an elusive task but can be opportunely attained by marketers by adding elements of eco-innovations and understanding mindsets of consumers to create win–win situations for themselves and consumers.

Originality/value

The results reinforced that emotional loyalty and Generations Y and Z vitally impact consumers' green buying decision within the framework of eco-innovation and cognitive factors.

Details

Management of Environmental Quality: An International Journal, vol. 33 no. 4
Type: Research Article
ISSN: 1477-7835

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Article
Publication date: 8 January 2020

Hailiang Su, Fengchong Lan, Yuyan He and Jiqing Chen

Because of the high computational efficiency, response surface method (RSM) has been widely used in structural reliability analysis. However, for a highly nonlinear limit state…

193

Abstract

Purpose

Because of the high computational efficiency, response surface method (RSM) has been widely used in structural reliability analysis. However, for a highly nonlinear limit state function (LSF), the approximate accuracy of the failure probability mainly depends on the design point, and the result is that the response surface function composed of initial experimental points rarely fits the LSF exactly. The inaccurate design points usually cause some errors in the traditional RSM. The purpose of this paper is to present a hybrid method combining adaptive moving experimental points strategy and RSM, describing a new response surface using downhill simplex algorithm (DSA-RSM).

Design/methodology/approach

In DSA-RSM, the operation mechanism principle of the basic DSA, in which local descending vectors are automatically generated, was studied. Then, the search strategy of the basic DSA was changed and the RSM approximate model was reconstructed by combining the direct search advantage of DSA with the reliability mechanism of response surface analysis.

Findings

The computational power of the proposed method is demonstrated by solving four structural reliability problems, including the actual engineering problem of a car collision. Compared to specific structural reliability analysis methods, the approach of modified DSA interpolation response surface for structural reliability has a good convergent capability and computational accuracy.

Originality/value

This paper proposes a new RSM technology based on proxy model to complete the reliability analysis. The originality of this paper is to present an improved RSM that adjusts the position of the experimental points judiciously by using the DSA principle to make the fitted response surface closer to the actual limit state surface.

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Article
Publication date: 17 March 2022

Thi Phuong Linh Nguyen

The purpose of this paper is to investigate factors affecting Vietnamese consumers’ intention and behavior toward “bringing your own shopping bags” (BYOB) instead of using plastic…

1049

Abstract

Purpose

The purpose of this paper is to investigate factors affecting Vietnamese consumers’ intention and behavior toward “bringing your own shopping bags” (BYOB) instead of using plastic bags based on integrating theories: theory of planned behavior (TPB) and norm activation model (NAM).

Design/methodology/approach

The study used a combination of in-depth interviews and large-scale surveys. Data were collected from 536 Vietnamese consumers to explore the relationship among eight factors in the research model, including behavior, intention, attitude (AT), subjective norms (SN), perceived behavioral control, the ascription of responsibility, awareness of consequences and personal norm (PN). The data collected went through quantitative analysis steps, including Cronbach’s alpha reliability test, exploratory factor analysis, confirmatory factor analysis and structural equation modeling for scales and hypotheses testing by using SPSS and AMOS data analysis tools.

Findings

The results show that in a developing country like Vietnam, attitude and PNs have a stronger impact on intention toward BYOB than other factors, and the study also reveals the moderate relationship between intention with actual behavior toward BYOB. The proposed hypotheses are all accepted except the hypothesis about the relationship between SN and PNs.

Research limitations/implications

The main limitation of this paper is that the integrative model of TPB and NAM only explains 57% of the variance of the intention toward BYOB.

Practical implications

Based on the results of the study, the author makes some suggestions for Vietnamese state management agencies to promote BYOB.

Originality/value

To the best of the authors’ knowledge, this study represents for the first time the application of an integrated model of TPB and NAM to learn about the intention and behavior toward BYOB.

Details

Journal of Social Marketing, vol. 12 no. 4
Type: Research Article
ISSN: 2042-6763

Keywords

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Article
Publication date: 14 March 2019

Hailiang Su, Fengchong Lan, Yuyan He and Jiqing Chen

Meta-model method has been widely used in structural reliability optimization design. The main limitation of this method is that it is difficult to quantify the error caused by…

237

Abstract

Purpose

Meta-model method has been widely used in structural reliability optimization design. The main limitation of this method is that it is difficult to quantify the error caused by the meta-model approximation, which leads to the inaccuracy of the optimization results of the reliability evaluation. Taking the local high efficiency of the proxy model, this paper aims to propose a local effective constrained response surface method (LEC-RSM) based on a meta-model.

Design/methodology/approach

The operating mechanisms of LEC-RSM is to calculate the index of the local relative importance based on numerical theory and capture the most effective area in the entire design space, as well as selecting important analysis domains for sample changes. To improve the efficiency of the algorithm, the constrained efficient set algorithm (ESA) is introduced, in which the sample point validity is identified based on the reliability information obtained in the previous cycle and then the boundary sampling points that violate the constraint conditions are ignored or eliminated.

Findings

The computational power of the proposed method is demonstrated by solving two mathematical problems and the actual engineering optimization problem of a car collision. LEC-RSM makes it easier to achieve the optimal performance, less feature evaluation and fewer algorithm iterations.

Originality/value

This paper proposes a new RSM technology based on proxy model to complete the reliability design. The originality of this paper is to increase the sampling points by identifying the local importance of the analysis domain and introduce the constrained ESA to improve the efficiency of the algorithm.

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Article
Publication date: 28 April 2022

Thi Phuong Linh Nguyen, Nhat Minh Tran, Thi Thanh Hoa Phan, Trong Nghia Vu, Manh Linh Tran and Thi Dao Nguyen

The purpose of this paper is to investigate the factors affecting Vietnamese consumers' intention and behavior towards “bringing your own shopping bags” (BYOB) instead of using…

715

Abstract

Purpose

The purpose of this paper is to investigate the factors affecting Vietnamese consumers' intention and behavior towards “bringing your own shopping bags” (BYOB) instead of using plastic bags based on the theory of interpersonal behavior (TIB).

Design/methodology/approach

We used a combination of in-depth interview and large-scale survey methods with the official research sample of 536 Vietnamese consumers to explore the relationship among factors in the research model including: attitude, affect, social factor, facilitating conditions, intention and behavior towards BYOB instead of using plastic bags. The collected data went through quantitative analysis steps including Cronbach's Alpha reliability test, exploratory factor analysis (EFA), confirmatory factor analysis (CFA) and structural equation modeling (SEM) for scales and hypotheses testing.

Findings

The results show that intention towards BYOB has a positive effect on consumers' behavior towards BYOB. Facilitating conditions have a stronger and more positive influence than attitude and affect intention towards BYOB. Meanwhile, the hypothesis about the relationship between social factors and intention towards BYOB was rejected by this study.

Research limitations/implications

The main limitation of this paper is that the findings of the present study are limited to elements of the TIB.

Practical implications

Based on the results of the study, we made some suggestions for state management agencies and retailers to promote intention and behavior towards BYOB instead of using plastic bags.

Originality/value

This study applies the TIB to understand the relationship between factors such as attitude, affect, social factors and facilitating conditions on intention and behavior towards BYOB instead of using plastic bags.

Details

Management of Environmental Quality: An International Journal, vol. 33 no. 6
Type: Research Article
ISSN: 1477-7835

Keywords

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Article
Publication date: 5 October 2015

Xiaoke Li, Haobo Qiu, Zhenzhong Chen, Liang Gao and Xinyu Shao

Kriging model has been widely adopted to reduce the high computational costs of simulations in Reliability-based design optimization (RBDO). To construct the Kriging model…

506

Abstract

Purpose

Kriging model has been widely adopted to reduce the high computational costs of simulations in Reliability-based design optimization (RBDO). To construct the Kriging model accurately and efficiently in the region of significance, a local sampling method with variable radius (LSVR) is proposed. The paper aims to discuss these issues.

Design/methodology/approach

In LSVR, the sequential sampling points are mainly selected within the local region around the current design point. The size of the local region is adaptively defined according to the target reliability and the nonlinearity of the probabilistic constraint. Every probabilistic constraint has its own local region instead of all constraints sharing one local region. In the local sampling region, the points located on the constraint boundary and the points with high uncertainty are considered simultaneously.

Findings

The computational capability of the proposed method is demonstrated using two mathematical problems, a reducer design and a box girder design of a super heavy machine tool. The comparison results show that the proposed method is very efficient and accurate.

Originality/value

The main contribution of this paper lies in: a new local sampling region computational criterion is proposed for Kriging. The originality of this paper is using expected feasible function (EFF) criterion and the shortest distance to the existing sample points instead of the other types of sequential sampling criterion to deal with the low efficiency problem.

Details

Engineering Computations, vol. 32 no. 7
Type: Research Article
ISSN: 0264-4401

Keywords

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Article
Publication date: 28 September 2023

Moein Beheshti, Hannan Amoozad Mahdiraji and Luis Rocha-Lona

Various publications have extensively documented the advantages of a circular economy in ensuring sustainability and limiting climate change. Despite academic records emphasising…

651

Abstract

Purpose

Various publications have extensively documented the advantages of a circular economy in ensuring sustainability and limiting climate change. Despite academic records emphasising the need to adopt this business strategy, entrepreneurs in developing countries prefer linear economies. This reluctance is attributable to several factors, including insufficient infrastructure and technology, limited financial access, inadequate education systems and the prevalence of informal enterprises. Therefore, a thorough analysis of the underlying economic, political and social conditions is required to identify the drivers of circular economies (CEs) and their contribution to entrepreneurship in developing countries.

Design/methodology/approach

In this study, the authors first conducted a comprehensive quantitative literature review based on LangChain to identify the critical CE drivers from the social, technological and organisational perspectives. Based on the input from the expert panel of Iranian academic and industry professionals, the authors applied an integrated fuzzy interpretive structural modelling and cross-impact matrix multiplication approach to classification (Fuzzy-ISM-MICMAC) to investigate the chronology of entrepreneurial drivers.

Findings

Level-based model results reveal entrepreneurial drivers in developing nations and their interrelationships, specifically underlining the importance of supply chain factors and stakeholder preferences. Thus, the differences between the perception of the main drivers in developed and developing economies can be identified, with the former paying particular attention to legislative and financial factors. The study's findings contribute to conserving resources, reducing waste and adopting more sustainable corporate practices, thereby assisting developing countries in achieving development goals.

Originality/value

This study employs an innovative quantitative systematic literature review approach that relies on a large language model to identify the drivers of the CE. Furthermore, it adopts a systematic approach to examine the enablers of the CE rather than a narrow and individual perspective of the entrepreneurial drivers. The study employs the fuzzy ISM MICMAC technique to showcase the prioritisation of entrepreneurial prospects in emerging economies.

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