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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.

Under the high-speed operating conditions, the effects of wheelset elastic deformation on the wheel rail dynamic forces will become more notable compared to the low-speed condition. In order to meet different analysis requirements and selecting appropriate models to analyzing the wheel rail interaction, it is crucial to understand the influence of wheelset flexibility on the wheel-rail dynamics under different speeds and track excitations condition.

The wheel rail contact points solving method and vehicle dynamics equations considering wheelset flexibility in the trajectory body coordinate system were investigated in this paper. As for the wheel-rail contact forces, which is a particular force element in vehicle multibody system, a method for calculating the Jacobian matrix of the wheel-rail contact force is proposed to better couple the wheel-rail contact force calculation with the vehicle dynamics response calculation. Based on the flexible wheelset modeling approach in this paper, two vehicle dynamic models considering the wheelset as both elastic and rigid bodies are established, two kinds of track excitations, namely normal measured track irregularities and short-wave irregularities are used, wheel-rail geometric contact characteristic and wheel-rail contact forces in both time and frequency domains are compared with the two models in order to study the influence of flexible wheelset rotation effect on wheel rail contact force.

Under normal track irregularity excitations, the amplitudes of vertical, longitudinal and lateral forces computed by the flexible wheelset model are smaller than those of the rigid wheelset model, and the virtual penetration and equivalent contact patch are also slightly smaller. For the flexible wheelset model, the wheel rail longitudinal and lateral creepages will also decrease. The higher the vehicle speed, the larger the differences in wheel-rail forces computed by the flexible and rigid wheelset model. Under track short-wave irregularity excitations, the vertical force amplitude computed by the flexible wheelset is also smaller than that of the rigid wheelset. However, unlike the excitation case of measured track irregularity, under short-wave excitations, for the speed within the range of 200 to 350 km/h, the difference in the amplitude of the vertical force between the flexible and rigid wheelset models gradually decreases as the speed increase. This is partly due to the contribution of wheelset’s elastic vibration under short-wave excitations. For low-frequency wheel-rail force analysis problems at speeds of 350 km/h and above, as well as high-frequency wheel-rail interaction analysis problems under various speed conditions, the flexible wheelset model will give results agrees better with the reality.

This study provides reference for the modeling method of the flexible wheelset and the coupling method of wheel-rail contact force to the vehicle multibody dynamics system. Furthermore, by comparative research, the influence of wheelset flexibility and rotation on wheel-rail dynamic behavior are obtained, which is useful to the application scope of rigid and flexible wheelset models.

Realistic composite vehicles with 2, 3, 5 and 9 axles, consisting of a truck with one or two trailers, are addressed in this paper by computational models for vehicle–bridge interaction analysis.

The vehicle–bridge interaction (VBI) models are formed by sets of 2-D rigid blocks interconnected by mass, damping and stiffness elements to simulate their suspension system. The passage of the vehicles is performed at different speeds. Several rolling surface profiles are admitted, considering the maintenance grade of the pavement. The spectral density functions are generated from an experimental database to form the longitudinal surface irregularity profiles. A computational code written in Phyton based on the finite element method was developed considering the Euler–Bernoulli beam model.

Several models of composite heavy vehicles are presented as manufactured and currently travel on major roads. Dynamic amplification factors are presented for each type of composite vehicle.

The VBI models for compound heavy vehicles are 2-D.

This work contributes to improving the safety and lifetime of the bridges, as well as the stability and comfort of the vehicles when passing over a bridge.

The structural response of the bridge is affected by the type and size of the compound vehicles, their speed and the conservative grade of the pavement. Moreover, one axle produces vibrations that can be superposed by the vibrations of the other axles. This effect can generate not usual dynamic responses.

The aim of this study is to question the relationship between architectural ethical codes and faults in earthquakes. Earthquakes have devastating effects on all societies in history and today. And the relationship and importance of the architect and building, one of the most important roles of these destructive effects, is once again revealed in every earthquake. Although there are some restrictions or warnings for architects and the architectural profession to reduce this destructive effect in many regulations and ethical codes, it is possible to see the defects caused by architectural design and the destruction caused by these defects in every new earthquake.

In this study, the most destructive earthquakes in Turkey in the past 20 years (Bingöl, Van, Elazig and Izmir) and the 1999 Marmara earthquake, which was the most destructive earthquake in Turkey’s recent history, and the damages occurred in these earthquakes and their causes were examined. Although the scope of the study is “destructive earthquakes that have occurred in the past 20 years in Turkey”, the Marmara Earthquake, which occurred in 1999, when the destructive effect of the earthquake was seen the most and architectural design errors were intense, was also included in the scope of the study. And to have a more comprehensive understanding of how these defects are examined in terms of ethical codes and to make a more comprehensive comparison, ethical codes from different countries in the world have been researched and a review has been made on topics such as public welfare, human rights and raising the standard of the profession.

This study concludes by reviewing the key factors learned from the examined ethical codes of different countries. Finding ethical codes of different countries was challenging to gain approval. In addition, the study ends with recommendations in terms of questioning the regulations and education curriculum relations on a country basis.

This study, which targets architect candidates who carry out the profession of architecture and continue their architectural education, evaluates the architectural design flaws seen in earthquakes through ethical codes and forms a basis for further studies.

The case study is designed to help students understand how the “growth at all costs” attitude can lead to compromised corporate governance in a start-up leading to disastrous implications for all the stakeholders. This case study aims to make students understand the components of the fraud triangle, the impact of financial fraud on various stakeholders, the role of venture capitalist (VC) investors and the importance of good corporate governance in start-ups. The case study presents an excellent opportunity for students to discuss the consequences of ignoring good governance in the pursuit of growth in a start-up. After analyzing the case study, the students shall be able to explain the concept of the fraud triangle and to be able to identify the motivation, opportunity and rationalization of financial irregularities in a start-up; analyze the impact of financial irregularities on various stakeholders; comprehend the business model of VCs and evaluate its influence on VC-funded start-ups; and appraise the importance of good corporate governance in start-ups.

The case study revolves around the confession of financial irregularities made by one of the cofounders of GoMechanic, a start-up headquartered in Gurugram, India. On January 18, 2023, Amit Bhasin confessed to financial irregularities in the company’s financial statements, leading to laying off 70% of the workforce of the company. GoMechanic had earlier raised close to US$62m [1] from maverick global investors including Sequoia Capital, Tiger Global, Orios Venture Partners and Chiratae Ventures, and was negotiating to raise Series D financing from the Japanese multinational SoftBank with aspirations to be a unicorn (start-up with a valuation of over $1bn). The confession led to a debate about the consequences of the “growth at all cost” culture being followed by start-ups as well as VCs. GoMechanic was not an isolated instance of a lack of governance in the start-ups. The confession had consequences not only for the GoMechanic but for the entire start-up ecosystem of India, which was the third largest in the world. Bhasin stated that the founders take full responsibility for the situation, and they were working on a plan which was most viable under the circumstances. However, it was not going to be easy to regain the confidence of the investors.

The case study is best suited for senior undergraduate- and graduate-level business school students and in executive education programs in courses such as corporate governance and ethics, private equity and entrepreneurial finance.

Teaching notes are available for educators only.

CSS 1: Accounting and finance

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.

Straightness measurement of rail weld joint is of essential importance to railway maintenance. Due to the lack of efficient measurement equipment, there has been limited in-depth research on rail weld joint with a 5-m wavelength range, leaving a significant knowledge gap in this field.

In this study, the authors used the well-established inertial reference method (IR-method), and the state-of-the-art multi-point chord reference method (MCR-method). Two methods have been applied in different types of rail straightness measurement trollies, respectively. These instruments were tested in a high-speed rail section within a certain region of China. The test results were ultimately validated through using traditional straightedge and feeler gauge methods as reference data to evaluate the rail weld joint straightness within the 5-m wavelength range.

The research reveals that IR-method and MCR-method produce reasonably similar measurement results for wavelengths below 1 m. However, MCR-method outperforms IR-method in terms of accuracy for wavelengths exceeding 3 m. Furthermore, it was observed that IR-method, while operating at a slower speed, carries the risk of derailing and is incapable of detecting rail weld joints and low joints within the track.

The research compare two methods’ measurement effects in a longer wavelength range and demonstrate the superiority of MCR-method.

This paper aims to examine the influence of procurement physiognomies on the creative accounting (CA) of listed health-care firms in Nigeria from 2016 to 2020.

This paper used positivist paradigm. Annual reports and accounts, questionnaire and e-mails were used to obtained and extract quantitative data. The data were analyzed using OLS regression.

The study found that, procurement planning, e-procurement and procurement legislation compliance possessed negative weighty consequence on CA of quoted Nigerian health-care corporations while outsourcing, procurement staff competency and strategic supplier partnership possess positive substantial impact on the firms’ CA. The article concluded that procurement physiognomies play an important role in managing CA of health-care firms.

This study findings are only applicable to listed health-care firms in Nigeria. It only used six procurement attributes. The research implication is that researchers are to use the findings in conducting further studies on procurement physiognomies and CA to help in coming up with ways of curbing irregularities in the organizations.

The health-care firms are to use the findings to come up with policies that ensure malpractices in procurement are curbed and CA is minimized to its barest level. Its societal implication is that the public is to use the findings in changing societal attitudes toward earnings manipulation.

Its societal implication is that the public is to use the findings in changing societal attitudes toward earnings manipulation.

To the best of the authors’ knowledge, this article is the first to evaluate the influence of procurement physiognomies on CA in Nigerian-listed health-care companies. Many researchers neglect how procurement is used to carry out a lot of CA and this study focuses on a mechanism for curtailing corruption.

This study aims to investigate cases of fraudulent financial statements that have occurred in Indonesia and explore the similarities of cases that existed in the period before and after the establishment of the Financial Services Authority.

This paper provides a descriptive examination of financial misstatements issued by different regimes by listed companies of the capital market and financial institution supervisory agency and the introduction of new financial service authority; among 93 listed companies that were subject to an official investigation arising from the publication of financial misstatements, these assessments were facilitated by mean of content analysis of annual reports following the announcement of an investigation.

The findings indicate that each regime has a specific pattern of financial statement fraud. It is found that senior management is responsible for most fraud, and recording a fictitious sale is the most common method of falsifying financial statements. Under the new regime, the publication of cases is limited since the introduction of risk-based supervision. Financial Services Authority is likely to fine and prosecute the director of a company as a perpetrator rather than a corporation as a legal entity.

This study contributes to the literature on the incidence of financial statement fraud in public companies and provides a detailed descriptive comparison of cases scrutinized by securities exchange commission in an emerging country.

This paper examines the relationship between indigenous cultures and employee efficiency and how cronyism strengthens or weakens the relationship in the Ghanaian state-owned enterprises (SOEs) in response to the employee efficiency.

This study employs a quantitative approach by a cross-sectional survey to collect data from 400 workers in ten SOEs in Ghana. The analysis is done by using descriptive statistics and hierarchical regression techniques.

The findings indicate that showing gratitude is the predominant indigenous culture in the SOEs of Ghana while irregularity (absenteeism) is not dominant. Moreover, the practice of cronyism is high. It reveals that the indigenous cultures, except for respect for the elderly, relate negatively to employee efficiency, and cronyism strengthens the relationship between indigenous cultures and employee efficiency.

The paper contributes to the literature by providing empirical evidence that cronyism effectively strengthens the relationship between indigenous cultures and employee efficiency in a developing country. Strategies to discourage cronyism should be the key focus of public administrators, as well as mechanisms to limit the practice of adverse indigenous cultures.