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The purpose of this paper is to develop a novel network and dynamic data envelopment analysis (DEA) model for evaluating sustainability of supply chains. In the proposed model, all links can be considered in calculation of efficiency score.

A dynamic DEA model to evaluate sustainable supply chains in which networks have series structure is proposed. Nature of free links is defined and subsequently applied in calculating relative efficiency of supply chains. An additive network DEA model is developed to evaluate sustainability of supply chains in several periods. A case study demonstrates applicability of proposed approach.

This paper assists managers to identify inefficient supply chains and take proper remedial actions for performance optimization. Besides, overall efficiency scores of supply chains have less fluctuation. By utilizing the proposed model and determining dual-role factors, managers can plan their supply chains properly and more accurately.

In real world, managers face with big data. Therefore, we need to develop an approach to deal with big data.

The proposed model offers useful managerial implications along with means for managers to monitor and measure efficiency of their production processes. The proposed model can be applied in real world problems in which decision makers are faced with multi-stage processes such as supply chains, production systems, etc.

For the first time, the authors present additive model of network-dynamic DEA. For the first time, the authors outline the links in a way that carry-overs of networks are connected in different periods and not in different stages.

This review aims to give a critical view of the wheel/rail high frequency vibration-induced vibration fatigue in railway bogie.

Vibration fatigue of railway bogie arising from the wheel/rail high frequency vibration has become the main concern of railway operators. Previous reviews usually focused on the formation mechanism of wheel/rail high frequency vibration. This paper thus gives a critical review of the vibration fatigue of railway bogie owing to the short-pitch irregularities-induced high frequency vibration, including a brief introduction of short-pitch irregularities, associated high frequency vibration in railway bogie, typical vibration fatigue failure cases of railway bogie and methodologies used for the assessment of vibration fatigue and research gaps.

The results showed that the resulting excitation frequencies of short-pitch irregularity vary substantially due to different track types and formation mechanisms. The axle box-mounted components are much more vulnerable to vibration fatigue compared with other components. The wheel polygonal wear and rail corrugation-induced high frequency vibration is the main driving force of fatigue failure, and the fatigue crack usually initiates from the defect of the weld seam. Vibration spectrum for attachments of railway bogie defined in the standard underestimates the vibration level arising from the short-pitch irregularities. The current investigations on vibration fatigue mainly focus on the methods to improve the accuracy of fatigue damage assessment, and a systematical design method for vibration fatigue remains a huge gap to improve the survival probability when the rail vehicle is subjected to vibration fatigue.

The research can facilitate the development of a new methodology to improve the fatigue life of railway vehicles when subjected to wheel/rail high frequency vibration.

According to the Association of Certified Fraud Examiners, financial statement fraud represents the smallest amount of fraud cases but results in the greatest monetary loss. The researcher previously investigated the characteristics of financial statement fraud and determined the presence of 16 fraud indicators. The purpose of this study is to establish whether investors and other stakeholders can detect and identify financial statement fraud using these characteristics in an analysis of a company’s annual report.

This study analyses a financial statement fraud case, using the same techniques that were previously applied, including horizontal, vertical and ratio analysis. These are preferred because stakeholders have relatively easy access to them.

The findings show several fraud characteristics, with a few additional ones not previously found prevalent. Financial statement fraud thus tends to differ between cases. It is also easier to detect and identify fraud indicators ex post facto.

This study is a practical case showing that financial statement fraud can be detected and identified in the financial statements of companies that commit fraud.

The safety and reliability of high-speed trains rely on the structural integrity of their components and the dynamic performance of the entire vehicle system. This paper aims to define and substantiate the assessment of the structural integrity and dynamical integrity of high-speed trains in both theory and practice. The key principles and approaches will be proposed, and their applications to high-speed trains in China will be presented.

First, the structural integrity and dynamical integrity of high-speed trains are defined, and their relationship is introduced. Then, the principles for assessing the structural integrity of structural and dynamical components are presented and practical examples of gearboxes and dampers are provided. Finally, the principles and approaches for assessing the dynamical integrity of high-speed trains are presented and a novel operational assessment method is further presented.

Vehicle system dynamics is the core of the proposed framework that provides the loads and vibrations on train components and the dynamic performance of the entire vehicle system. For assessing the structural integrity of structural components, an open-loop analysis considering both normal and abnormal vehicle conditions is needed. For assessing the structural integrity of dynamical components, a closed-loop analysis involving the influence of wear and degradation on vehicle system dynamics is needed. The analysis of vehicle system dynamics should follow the principles of complete objects, conditions and indices. Numerical, experimental and operational approaches should be combined to achieve effective assessments.

The practical applications demonstrate that assessing the structural integrity and dynamical integrity of high-speed trains can support better control of critical defects, better lifespan management of train components and better maintenance decision-making for high-speed trains.

The study aims to investigate cultural aspects in supply chains, analysing the effect that local customs may have in the quality of buyer–supplier relationships. Building on the premisses of social exchange theory (SET), it concentrates on the impacts that suppliers’ use of local practices and informal networks may have in buyers’ attitudes and perceptions. The issues addressed and the empirical evidence provided represent initial, yet important steps in the fulfilment of the ‘cultural void’ within supply chain social sustainability (SCCS) literature.

Through a role-playing experiment applied to a total sample of 468 participants, the effects of Chinese guanxi, Russian blat, South Korean yongo and Brazilian jeitinho on buyers’ satisfaction, buyers’ commitment, trust and solution severity are measured by their use to access informal networks as solutions to both common (i.e. documentation irregularities) and extraordinary (i.e. modern slavery) supply chain problems.

Results show that, while the activation of informal networks may impact buyers’ perceptions, the use of some local practices by suppliers (i.e. Chinese guanxi and Brazilian jeitinho) cause greater variations in buyers’ attitudes and perceptions than others (i.e. South Korean yongo and Russian blat), with ethical offences (i.e. modern slavery) and higher levels of buyers’ dependency acting as catalysts of these processes.

The investigation of cultural practices typical of economically peripheral countries contributes to the understanding of new facets of buyer–supplier relationships, with the investigation of non-Northwestern practices being particularly important in this regard.

This study proposes a Bayesian approach to analyze structural breaks and examines whether structural changes have occurred, at the onset of civil war, with respect to economic development and population during the period from 1945 to 1999.

In the Bayesian logit regression changepoint model, parameters of covariates are allowed to shift individually, regime transitions can move back and forth, and the model is applicable to cross-sectional, time-series data.

Contrary to popular belief that the causal process of civil war changed with the end of the Cold War, the empirical analysis shows that the regression relationships between civil war and economic development, as well as between civil war and population, remain quite stable during the study period.

This is the first to develop a Bayesian logit regression changepoint model and to apply it to studies of economic development and civil war.

This study aims to explore how corporate discourses enact legitimation strategies aimed at repairing pragmatic, moral and cognitive legitimacy types (Suchman, 1995) after a scandal involving sustainability, namely, the Volkswagen’s 2015 diesel scandal.

By drawing on the discursive nature of legitimacy, this study conducts a critical discourse analysis to identify how the scandal is depicted and which semantic, grammatical and lexical features characterise discourses. It then relates discourses and their features to legitimation strategies that help repair diverse types of legitimacy.

To repair pragmatic legitimacy, discourses on a few actors and processes enact strategies of creating monitors and avoiding panic. Such discourses include grammatical features only. Discourses on the event, actors, processes and topics of apology, trust and integrity aim to repair moral legitimacy. Enriched with grammatical and lexical features, they mobilise disassociation, excuse, justify and restructure strategies. Discourses on the event, actors, processes and topics of corporate qualities, history and future strategy help repair cognitive legitimacy by enacting an avoiding panic strategy. Grammatical, lexical and semantic features characterise such discourses.

The study reveals the potentials of critical discourse analysis to bring out from texts practical modes of communicating, and specifically those discourses and features of discourses that serve legitimacy purposes.

This study offers insights into the connection among discourses, relegitimation strategies and legitimacy types by combining the discursive nature of legitimacy with critical discourse analysis. It also contributes to the growing literature on how organisations face the legitimacy challenges raised by scandals involving sustainability.

This paper aims to examine the association between the working relationship between internal and external auditors and the moral courage of internal auditors to report management fraud in the Tunisian setting.

Data are gathered from 163 internal auditors working in Tunisian companies and a partial least squares–structural equation model (PLS-SEM) is used to test the hypothesis regarding the effect of the cooperation between internal and external auditors on internal auditors’ moral courage.

The results of this study provide strong empirical support for the positive impact of the working relationship between internal and external auditors on internal auditors’ moral courage to report management fraud and unethical behaviors.

The reported results increase the awareness of Tunisian regulators to enact regulations that strengthen the collaboration between internal and external auditors to promote internal auditors’ moral courage and then limit fraud and improve organizational performance in the Tunisian setting.

This paper fills one of the major research gaps in internal audit and moral courage research streams by revealing that the courageous behavior of internal auditors can be fostered by specific means efficacy such as the working relationship between internal and external auditors.

This study aims to analyze the factors, evaluation techniques of the durability of existing railway engineering.

China has built a railway network of over 150,000 km. Ensuring the safety of the existing railway engineering is of great significance for maintaining normal railway operation order. However, railway engineering is a strip structure that crosses multiple complex environments. And railway engineering will withstand high-frequency impact loads from trains. The above factors have led to differences in the deterioration characteristics and maintenance strategies of railway engineering compared to conventional concrete structures. Therefore, it is very important to analyze the key factors that affect the durability of railway structures and propose technologies for durability evaluation.

The factors that affect the durability and reliability of railway engineering are mainly divided into three categories: material factors, environmental factors and load factors. Among them, material factors also include influencing factors, such as raw materials, mix proportions and so on. Environmental factors vary depending on the service environment of railway engineering, and the durability and deterioration of concrete have different failure mechanisms. Load factors include static load and train dynamic load. The on-site rapid detection methods for five common diseases in railway engineering are also proposed in this paper. These methods can quickly evaluate the durability of existing railway engineering concrete.

The research can provide some new evaluation techniques and methods for the durability of existing railway engineering.

Laser sintering of polyamide lattice-based lightweight fairing components for subsequent racetrack testing requires a high quality and a reliable design. Hence, the purpose of this study was to develop a design methodology for such additively manufactured prototypes, considering efficient generation and structural simulation of boundary conformal non-periodic lattices, optimization of production parameters as well as experimental validation.

Multi-curved, sandwich structure-based demonstrators were designed, simulated and experimentally tested with boundary conformal lattice cells. The demonstrator’s non-periodic lattice cells were simplified by forward homogenization processes. To represent the stiffness of the top and bottom face sheet, constant isotropic and mapped transversely isotropic simulation approaches were compared. The dimensional accuracy of lattice cells and demonstrators were measured with a gauge caliper and a three-dimensional scanning system. The optimized process parameters for lattice structures were transferred onto a large volume laser sintering system. The stiffness of each finite element analysis was verified by an experimental test setup including a digital image correlation system.

The stiffness prediction of the mapped was superior to the constant approach and underestimated the test results with −6.5%. Using a full scale fairing the applicability of the development process was successfully demonstrated.

The design approach elaborated in this research covers aspects from efficient geometry generation over structural simulation to experimental testing of produced parts. This methodology is not only relevant in the context of motor sports but is transferrable for all additively manufactured large scale components featuring a complex lattice sub-structure and is, therefore, relevant across industries.