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Article
Publication date: 22 October 2021

Zhaoyu Ku, Qiwen Xue, Gaping Wang and Shuang Liu

Aiming at the problems of poor accuracy and limitation in strength assessment of spot welding vehicle body caused by uncertain factors, such as key component size and…

Abstract

Purpose

Aiming at the problems of poor accuracy and limitation in strength assessment of spot welding vehicle body caused by uncertain factors, such as key component size and nugget diameter, the numerical models of strength uncertainty analysis of spot-welded joints were constructed based on evidence theory and fuzzy theory.

Design/methodology/approach

Evidence theory and fuzzy theory are used to deal with the uncertainty of design parameter, and differential evolution algorithms are used to calculate the propagation process of uncertainty in this model. Furthermore, efficient relationship between the strength of welded joints and each design parameter is constructed by using response surface proxy model, which effectively avoids the problem of repeated complex finite element analysis in uncertainty analysis.

Findings

The results show that the constructed uncertainty numerical model is effective for the multiple uncertainties and give interval results under different probabilities and affiliations, which can more effectively evaluate the strength of the welded body structure to avoid overly conservative estimates for deterministic design.

Originality/value

The evidence theory is improved and combined with differential evolution algorithm and response surface method to effectively improve the computational efficiency. Based on the improved evidence theory and fuzzy algorithm, the numerical models for the uncertainty analysis of solder joint strength of welded structures are constructed and their feasibility is verified.

Details

International Journal of Structural Integrity, vol. 13 no. 1
Type: Research Article
ISSN: 1757-9864

Keywords

Article
Publication date: 22 June 2010

Ole Jonny Klakegg, Olav Torp and Kjell Austeng

The purpose of this paper is to describe the transfer of experiences to improve the basis for overcoming the dilemma of trying to achieve analyses and systems that are…

Abstract

Purpose

The purpose of this paper is to describe the transfer of experiences to improve the basis for overcoming the dilemma of trying to achieve analyses and systems that are both good and simple. The quality of decisions relating to projects depends on how well the assumed basis for the project actually fit the reality of the situation in which the consequences occur. Good value and cost estimations support good decisions about projects insofar as the assumptions on which they are based mirror the reality, and the decision makers can understand the analysis.

Design/methodology/approach

The paper uses a longitudinal case study and qualitative analysis. Data relating to a large number of cases have become available to the authors through many years of research and consulting activities. Through joint experience and discussion the patterns are analysed. This paper is descriptive with respect to the challenges and empirical examples. The analysis itself ends with a rather normative conclusion.

Findings

There is a dilemma embedded in the processes used to analyse uncertainty and risks associated with projects. On the one hand, an important task is to reduce the complexity of a given situation to render the issues sufficiently simple for them to be understood and assessed. On the other hand, the models and assumptions upon which an analysis is based have to be sufficiently precise and detailed in order to make sense. The same dilemma is found when considering actions to address risks and uncertainties, as well as in designing management systems. It is concluded that the dilemma is real. Solutions have to be found among both good and simple options.

Research limitations/implications

The paper does not answer questions on “how to” and does not dig deep into theoretical perspectives on the current dilemma. More research to understand all aspects of the issue is needed.

Practical implications

Uncertainty analysis and management systems have to be good (precise enough) and at the same time simple (practical). There is no value unless it is used. Practical examples in the paper are intended to help practitioners identify alternative options.

Originality/value

The dilemma of good and simple has not been explicitly addressed before in light of practical experience and theory. The value added is increased awareness of an important problem in analytical processes.

Details

International Journal of Managing Projects in Business, vol. 3 no. 3
Type: Research Article
ISSN: 1753-8378

Keywords

Article
Publication date: 13 August 2019

Hui Lü, Kun Yang, Wen-bin Shangguan, Hui Yin and DJ Yu

The purpose of this paper is to propose a unified optimization design method and apply it to handle the brake squeal instability involving various uncertainties in a…

Abstract

Purpose

The purpose of this paper is to propose a unified optimization design method and apply it to handle the brake squeal instability involving various uncertainties in a unified framework.

Design/methodology/approach

Fuzzy random variables are taken as equivalent variables of conventional uncertain variables, and a unified response analysis method is first derived based on level-cut technique, Taylor expansion and central difference scheme. Next, a unified reliability analysis method is developed by integrating the unified response analysis and fuzzy possibility theory. Finally, based on the unified reliability analysis method, a unified reliability-based optimization model is established, which is capable of optimizing uncertain responses in a unified way for different uncertainty cases.

Findings

The proposed method is extended to perform squeal instability analysis and optimization involving various uncertainties. Numerical examples under eight uncertainty cases are provided and the results demonstrate the effectiveness of the proposed method.

Originality/value

Most of the existing methods of uncertainty analysis and optimization are merely effective in tackling one uncertainty case. The proposed method is able to handle the uncertain problems involving various types of uncertainties in a unified way.

Details

Engineering Computations, vol. 37 no. 1
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 1 March 2006

Jan Emblemsvåg and Lars Endre Kjølstad

The article sets out to discuss and present a solution to the fact that various qualitative risk analyses of the same problem can reach significantly different conclusions.

4958

Abstract

Purpose

The article sets out to discuss and present a solution to the fact that various qualitative risk analyses of the same problem can reach significantly different conclusions.

Design/methodology/approach

By reviewing a common risk analysis approach and identifying where the possible problems arise, the authors propose ways to overcome the problems based on what they have found in the literature in general.

Findings

There are ways to greatly reduce the problems, but this requires a risk analysis approach in which information quality and consistency are the subject of greater focus.

Research limitations/implications

The definitions used, Monte Carlo methods and the analytical hierarchy process are well tested in countless applications. Hence, the authors believe that this work possesses no major limitations.

Practical implications

The approach has only been applied to theoretical situations; real‐life situations are needed to address possible practical limitations.

Originality/value

The paper illustrates the importance of distinguishing between “uncertainty”, “risk” and “capabilities” and the associated implications. It also shows how this can be done in a logically consistent way using the analytical hierarchy process so that the problem of inconsistency is reduced, and how the analysis can be used to systematically improve itself. The proposed risk analysis is a novel approach that has, to the authors' knowledge, never been thought of before.

Details

Management Decision, vol. 44 no. 3
Type: Research Article
ISSN: 0025-1747

Keywords

Article
Publication date: 26 February 2019

Shahab Shoar, Farnad Nasirzadeh and Hamid Reza Zarandi

The purpose of this paper is to present a fault tree (FT)-based approach for quantitative risk analysis in the construction industry that can take into account both…

Abstract

Purpose

The purpose of this paper is to present a fault tree (FT)-based approach for quantitative risk analysis in the construction industry that can take into account both objective and subjective uncertainties.

Design/methodology/approach

In this research, the identified basic events (BEs) are first categorized based on the availability of historical data into probabilistic and possibilistic. The probabilistic and possibilistic events are represented by probability distributions and fuzzy numbers, respectively. Hybrid uncertainty analysis is then performed through a combination of Monte Carlo simulation and fuzzy set theory. The probability of occurrence of the top event is finally calculated using the proposed FT-based hybrid uncertainty analysis method.

Findings

The efficiency of the proposed method is demonstrated by implementing in a real steel structure project. A quantitative risk assessment is performed for weld cracks, taking into account of both types of uncertainties. An importance analysis is finally performed to evaluate the contribution of each BE to the probability of occurrence of weld cracks and adopt appropriate response strategies.

Research limitations/implications

In this research, the impact of objective (aleatory) dependence between the occurrences of different BEs and subjective (epistemic) dependence between estimates of the epistemically uncertain probabilities of some BEs are not considered. Moreover, there exist limitations to the application of fuzzy set rules, which were used for aggregating experts’ opinions and ranking purposes of the BEs in the FT model. These limitations can be investigated through further research.

Originality/value

It is believed that the proposed hybrid uncertainty analysis method presents a robust and powerful tool for quantitative risk analysis, as both types of uncertainties are taken into account appropriately.

Content available
Article
Publication date: 14 April 2022

Son Nguyen, Peggy Shu-Ling Chen and Yuquan Du

Container shipping is a crucial component of the global supply chain that is affected by a large range of operational risks with high uncertainty, threatening the…

Abstract

Purpose

Container shipping is a crucial component of the global supply chain that is affected by a large range of operational risks with high uncertainty, threatening the stability of service, manufacture, distribution and profitability of involved parties. However, quantitative risk analysis (QRA) of container shipping operational risk (CSOR) is being obstructed by the lack of a well-established theoretical structure to guide deeper research efforts. This paper proposes a methodological framework to strengthen the quality and reliability of CSOR analysis (CSORA).

Design/methodology/approach

Focusing on addressing uncertainties, the framework establishes a solid, overarching and updated basis for quantitative CSOR analysis. The framework consists of clearly defined elements and processes, including knowledge establishing, information gathering, aggregating multiple sources of data (social/deliberative and mathematical/statistical), calculating risk and uncertainty level, and presenting and interpreting quantified results. The framework is applied in a case study of three container shipping companies in Vietnam.

Findings

Various methodological contributions were rendered regarding CSOR characteristics, settings of analysis models, handling of uncertainties and result interpretation. The empirical study also generated valuable managerial implications regarding CSOR management policies.

Originality/value

This paper fills the gap of an updated framework for CSOR analysis considering the recent advancements of container shipping operations and risk management. The framework can be used by both practitioners as a tool for CSOR analysis and scholars as a test bench to facilitate the comparison and development of QRA models.

Details

Maritime Business Review, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 2397-3757

Keywords

Content available
Article
Publication date: 24 September 2019

Farman Afzal, Shao Yunfei, Mubasher Nazir and Saad Mahmood Bhatti

In the past decades, artificial intelligence (AI)-based hybrid methods have been increasingly applied in construction risk management practices. The purpose of this paper…

2160

Abstract

Purpose

In the past decades, artificial intelligence (AI)-based hybrid methods have been increasingly applied in construction risk management practices. The purpose of this paper is to review and compile the current AI methods used for cost-risk assessment in the construction management domain in order to capture complexity and risk interdependencies under high uncertainty.

Design/methodology/approach

This paper makes a content analysis, based on a comprehensive literature review of articles published in high-quality journals from the years 2008 to 2018. Fuzzy hybrid methods, such as fuzzy-analytical network processing, fuzzy-artificial neural network and fuzzy-simulation, have been widely used and dominated in the literature due to their ability to measure the complexity and uncertainty of the system.

Findings

The findings of this review article suggest that due to the limitation of subjective risk data and complex computation, the applications of these AI methods are limited in order to address cost overrun issues under high uncertainty. It is suggested that a hybrid approach of fuzzy logic and extended form of Bayesian belief network (BBN) can be applied in cost-risk assessment to better capture complexity-risk interdependencies under uncertainty.

Research limitations/implications

This study only focuses on the subjective risk assessment methods applied in construction management to overcome cost overrun problem. Therefore, future research can be extended to interpret the input data required to deal with uncertainties, rather than relying solely on subjective judgments in risk assessment analysis.

Practical implications

These results may assist in the management of cost overrun while addressing complexity and uncertainty to avoid chaos in a project. In addition, project managers, experts and practitioners should address the interrelationship between key complexity and risk factors in order to plan risk impact on project cost. The proposed hybrid method of fuzzy logic and BBN can better support the management implications in recent construction risk management practice.

Originality/value

This study addresses the applications of AI-based methods in complex construction projects. A proposed hybrid approach could better address the complexity-risk interdependencies which increase cost uncertainty in project.

Details

International Journal of Managing Projects in Business, vol. 14 no. 2
Type: Research Article
ISSN: 1753-8378

Keywords

Article
Publication date: 21 September 2022

Sifeng Liu and Wei Tang

The purpose of this paper is to explore new ways and lay a solid foundation to solve the problem of reliability growth analysis of major aerospace equipment with various…

Abstract

Purpose

The purpose of this paper is to explore new ways and lay a solid foundation to solve the problem of reliability growth analysis of major aerospace equipment with various uncertainty data through propose new concepts of general uncertainty data (GUD) and general uncertainty variable (GUV) and build the operation system of GUVs.

Design/methodology/approach

The characteristics of reliability growth data of major aerospace equipment and the limitations of current reliability growth models have been analyzed at first. The most commonly used uncertainty system analysis methods of probability statistics, fuzzy mathematics, grey system theory and rough set theory have been introduced. The concepts of GUD and GUV for reliability growth data analysis of major aerospace equipment are proposed. The simplified form of GUV based on the “kernel” and the degree of uncertainty of GUV is defined. Then an operation system of GUVs is built.

Findings

(1) The concept of GUD; (2) the concept of GUV; (3) The novel operation rules of GUVs with simplified form.

Practical implications

The method exposed in this paper can be used to integrate complex reliability growth data of major aerospace equipment. The reliability growth models based on GUV can be built for reliability growth evaluation and forecasting of major aerospace equipment in practice. The reliability evaluation example of a solid rocket motor shows that the concept and idea proposed in this paper are feasible. The research of this paper opens up a new way for the analysis of complex uncertainty data of reliability growth of major aerospace equipment. Moreover, the operation of GUVs could be extended to the case of algebraic equation, differential equation and matrix which including GUVs.

Originality/value

The new concepts of GUD and GUV are given for the first time. The novel operation rules of GUVs with simplified form were constructed.

Article
Publication date: 18 July 2008

Elizabeth Atherton, Nick French and Laura Gabrielli

Real estate development appraisal is a quantification of future expectations. The appraisal model relies upon the valuer/developer having an understanding of the future in…

2160

Abstract

Purpose

Real estate development appraisal is a quantification of future expectations. The appraisal model relies upon the valuer/developer having an understanding of the future in terms of the future marketability of the completed development and the future cost of development. In some cases the developer has some degree of control over the possible variation in the variables. However, other variables are totally dependent upon the vagaries of the market at the completion date. To try to address the risk of a different outcome to the one expected the developer will often carry out a sensitivity analysis on the development. This paper aims to look at the processes for so doing and the role of the decision maker in the analysis.

Design/methodology/approach

Traditional sensitivity analysis has generally only looked at the best and worst scenarios and has focused on the anticipated or expected outcomes. This does not take into account uncertainty and the range of outcomes that can happen. A fuller analysis should include examination of the uncertainties in each of the components of the appraisal and account for the appropriate distributions of the variables. This requires a standardised approach and the use of a generic forecasting software package.

Findings

There are numerous risks involved in the development of real estate. By allowing the decision maker to contribute to the assessment of these risks, the analysis provides the decision maker with a greater understanding of the critical variables and their impact upon the viability of the final scheme.

Originality/value

This analysis shows that developers can get a better understanding of the upside and downside risks associated with their project.

Details

Journal of European Real Estate Research, vol. 1 no. 2
Type: Research Article
ISSN: 1753-9269

Keywords

Article
Publication date: 28 June 2022

Ana María García-Pérez and Vanessa Yanes-Estévez

This work develops a longitudinal analysis of perceived environmental uncertainty applying the Rasch methodology (1960). The environmental uncertainty is defined as an…

Abstract

Purpose

This work develops a longitudinal analysis of perceived environmental uncertainty applying the Rasch methodology (1960). The environmental uncertainty is defined as an individual's perceived inability to predict the environment accurately (Milliken, 1987). The study focuses on analysing the state uncertainty from the perspective of the information and under the cognitive approach to the business reality.

Design/methodology/approach

Rasch measurement theory (1960) is applied, specifically the differential item functioning analysis based on the responses to a survey of SMEs.

Findings

The main sources of uncertainty for all the SMEs in the sample are two sectors in their general environment: economic and political-legal ones. These segments are the only ones in the environment that generate uncertainty that in 2016 is significantly different from that in 2019, being lower in the latter year.

Originality/value

This is a pioneering analysis of uncertainty both for its longitudinal nature and the methodology applied.

Details

Journal of Advances in Management Research, vol. 19 no. 5
Type: Research Article
ISSN: 0972-7981

Keywords

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