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The mixing of fuel and air plays a pivotal role in enhancing combustion in supersonic regime. Proper mixing stabilizes the flame and prevents blow-off. Blow-off is due to the shorter residence time of fuel and air in the combustor, as the flow is in supersonic regime. The flame is initiated in the local subsonic region created using a flameholder within the supersonic combustor. This study aims to design an effective flameholder which increases the residence time of fuel in the combustor allowing proper combustion preventing blow-off and other instabilities.

The geometry of the strut-based flameholder is altered in the present study to induce a streamwise motion of the fluid downstream of the strut. The streamwise motion of the fluid is initiated by the ramps and grooves of the strut geometry. The numerical simulations were carried out using ANSYS Fluent and are validated against the available experimental and numerical results of cold flow with hydrogen injection using plain strut as the flameholder. In the present study, numerical investigations are performed to analyse the effect on hydrogen injection in strut-based flameholders with ramps and converging grooves using Reynolds-averaged Navier–Stokes equation coupled with Menter’s shear stress transport k-ω turbulence model. The analysis is done to determine the effect of geometrical parameters and flow parameter on the flow structures near the base of the strut where thorough mixing takes place. The geometrical parameters under consideration include the ramp length, groove convergence angle, depth of the groove, groove compression angle and the Mach number. Two different strut configurations, namely, symmetric and asymmetric struts were also studied.

Higher turbulence and complex flow structures are visible in asymmetric strut configuration which develops better mixing of hydrogen and air compared to symmetric strut configuration. The variation in the geometric parameters develop changes in the fluid motion downstream of the strut. The fluid passing through the converging grooves gets decelerated thereby reducing the Mach number by 20% near the base of the strut compared to the straight grooved strut. The shorter ramps are found to be more effective, as the pressure variation in lateral direction is carried along the strut walls downstream of the strut increasing the streamwise motion of the fluid. The decrease in the depth of the groove increases the recirculation zone downstream of the strut. Moreover, the increase in the groove compression angle also increases the turbulence near the base of the strut where the fuel is injected. Variation in the injection port location increases the mixing performance of the combustor by 25%. The turbulence of the fuel jet stream is considerably changed by the increase in the injection velocity. However, the change in the flow field properties within the flow domain is marginal. The increase in fuel mass flow rate brings about considerable change in the flow field inducing stronger shock structures.

The present study identifies the optimum geometry of the strut-based flameholder with ramps and converging grooves. The reaction flow modelling may be performed on the strut geometry incorporating the design features obtained in the present study.

Decisions by construction contractors to bid (or not to bid) require the thorough assessment and evaluation of factors relevant to the decision, as well as the quantification of their combined impact, to produce successful bid/no-bid decisions. The purpose of this study is to present a fuzzy fault tree model to assist construction contractors to more efficiently bid for future projects.

The proposed model consist of two stages: first, identification of the factors that affect bidding decision using a questionnaire survey after an extensive literature review, and second, usage of the identified factors to build a fuzzy fault tree model to simulate the bidding decision.

A list of 15 factors that affect bid/no-bid decisions was identified. Analysis of factors revealed that the highest-ranking factors were related to financial aspects of the project. A case study is presented to demonstrate the capabilities of the model, and a fuzzy important analysis is performed on the basic events to demonstrate the differences between three contractors’ bid/no-bid decisions. The results reveal that there is variation between the decisions of each contractor based on their willingness to participate. Besides, the influence of evaluation factors on the final decision for each contractor is different.

The study contributes to the body of knowledge on tendering and bidding practices. The proposed model incorporated the fuzzy set theory, which suits human subjectivity. The proposed methodology overcomes the limitations of previous models as it can, using the linear pool opinion principle, combine and weigh the evaluations of multiple experts. In addition, the model is convenient for situations where historical data are not available.

This study aims to bring awareness to the developing of fault detection systems using the data collected from sensor devices/physical devices of various systems for predictive maintenance. Opportunities and challenges in developing anomaly detection algorithms for predictive maintenance and unexplored areas in this context are also discussed.

For conducting a systematic review on the state-of-the-art algorithms in fault detection for predictive maintenance, review papers from the years 2017–2021 available in the Scopus database were selected. A total of 93 papers were chosen. They are classified under electrical and electronics, civil and constructions, automobile, production and mechanical. In addition to this, the paper provides a detailed discussion of various fault-detection algorithms that can be categorised under supervised, semi-supervised, unsupervised learning and traditional statistical method along with an analysis of various forms of anomalies prevalent across different sectors of industry.

Based on the literature reviewed, seven propositions with a focus on the following areas are presented: need for a uniform framework while scaling the number of sensors; the need for identification of erroneous parameters; why there is a need for new algorithms based on unsupervised and semi-supervised learning; the importance of ensemble learning and data fusion algorithms; the necessity of automatic fault diagnostic systems; concerns about multiple fault detection; and cost-effective fault detection. These propositions shed light on the unsolved issues of predictive maintenance using fault detection algorithms. A novel architecture based on the methodologies and propositions gives more clarity for the reader to further explore in this area.

Papers for this study were selected from the Scopus database for predictive maintenance in the field of fault detection. Review papers published in this area deal only with methods used to detect anomalies, whereas this paper attempts to establish a link between different industrial domains and the methods used in each industry that uses fault detection for predictive maintenance.

The statistical report published by the Iranian Social Security Organization in 2012 showed that, of all industries, the construction industry is associated with the highest number of work-related accidents. Furthermore, as this sector contains a large human workforce, identification of the factors contributing to the occurrence of such accidents is vital. The paper aims to discuss these issues.

Furthermore, as this sector contains a large human workforce, identification of the factors contributing to the occurrence of such accidents is vital. In the present study, such factors were initially identified, after which the most important of these, managerial factors, were selected. Subsequently, the identification of the causes of the managerial factors was carried out with the use of the fault tree analysis (FTA) method and application of OR and AND entries.

Since it is difficult to determine the probability of occurrence of events in this industry with certainty, and because gray numbers (numbers of which the exact value is unknown, and which represent uncertain information) have a strong relationship with human expressions, the probability of occurrence of the main undesired events was also evaluated using the gray numbers as input entries, in addition to ranking the probability of occurrence of intermediate events.

The findings revealed that FTA using gray numbers is a useful and effective tool in risk assessment.

This paper aims to investigate the effect of mining supervisor behaviour, safety motivation and perceived job insecurity on Ghanaian underground miner’s safety citizenship behaviour.

The authors proposed a conceptual framework that tested supervisor behaviour as an independent variable, safety motivation as a mediator variable, perceived job insecurity as a moderator variable and safety citizenship behaviour as a dependent variable. The authors tested the hypothesized relationships using 351 valid responses collected through a structured questionnaire using hierarchical regression analysis.

Results revealed that both components of supervisor behaviour significantly influenced safety motivation and safety citizenship behaviour. Furthermore, safety motivation could mediate the relationships between both components of supervisor behaviour and safety citizenship behaviour. Also, perceived job insecurity failed to moderate the relationship between safety motivation and safety citizenship behaviour.

This current study is vital for managerial practices. The complex conceptual framework also contributes to offering different ways of understanding how supervisors’ behaviours can catalyze improvement or worsen safety outcomes.

The purpose of this paper is to examine the role of safety participation as a mediator in the relationship between the six facets of safety management practices (i.e. management commitment, safety training, worker’s involvement, safety communication and feedback, safety rules and procedures, and safety promotion policies) and safety compliance.

A survey of 74 employees of small and medium enterprises (SMEs) in the northern region of Peninsular Malaysia was carried out. Self-reported measures were used to obtain data on workplace safety dimensions and safety behavior. The partial least square structural model analysis was used to ascertain the proposed relationships.

The present study found that only three dimensions of safety management practices (management commitment, safety training, and safety rules and procedures) were significantly related to safety compliance. Of these, safety participation mediated the link between management commitment and safety training and safety compliance.

The small sample size may limit the generalizability of the findings. Second, the correlational nature of the study did not permit causation to be implied. However, despite these limitations, while safety performance can be theorized to trigger the establishment of safety management practices, such theoretical perspective tends to connote reactivity rather than proactivity of the decision-making process.

The study highlights the role of the voluntary behavior of employees in promoting a safe work environment. Business owners are recommended to provide safety training in which the employees are stressed on their crucial role in safety and use this knowledge to educate and convince their co-workers to work safely.

Literature indicates the lack of studies on safety research in SMEs. Furthermore, such studies are justified because SMEs are likely to have more risks of occupational accidents and injuries. More importantly, this research highlights the importance of the voluntary behaviors of employees (i.e. safety participation) in promoting a safe work environment. As SMEs tend to have limited resources to implement a comprehensive OSH management system, using the employees as the safety agents at work can be an effective way toward accomplishing safety performance.

The paper provides an overview of research published in the innovation and operations management (IOM) literature on 15 methods for cost management in new product development, and it provides a comparison to an earlier review of the management accounting (MA) literature (Wouters & Morales, 2014).

This structured literature search covers papers published in 23 journals in IOM in the period 1990–2014.

The search yielded a sample of 208 unique papers with 275 results (one paper could refer to multiple cost management methods). The top 3 methods are modular design, component commonality, and product platforms, with 115 results (42%) together. In the MA literature, these three methods accounted for 29%, but target costing was the most researched cost management method by far (26%). Simulation is the most frequently used research method in the IOM literature, whereas this was averagely used in the MA literature; qualitative studies were the most frequently used research method in the MA literature, whereas this was averagely used in the IOM literature. We found a lot of papers presenting practical approaches or decision models as a further development of a particular cost management method, which is a clear difference from the MA literature.

This review focused on the same cost management methods, and future research could also consider other cost management methods which are likely to be more important in the IOM literature compared to the MA literature. Future research could also investigate innovative cost management practices in more detail through longitudinal case studies.

This review of research on methods for cost management published outside the MA literature provides an overview for MA researchers. It highlights key differences between both literatures in their research of the same cost management methods.

Designing and developing safe systems has been a persistent challenge in health care, and in surgical settings in particular. In efforts to promote safety, safety culture, i.e., shared values regarding safety management, is considered a key driver of high-quality, safe healthcare delivery. However, changing organizational culture so that it emphasizes and promotes safety is often an elusive goal. The Safe Surgery Checklist is an innovative tool for improving safety culture and surgical care safety, but evidence about Safe Surgery Checklist effectiveness is mixed. We examined the relationship between changes in management practices and changes in perceived safety culture during implementation of safe surgery checklists. Using a pre-posttest design and survey methods, we evaluated Safe Surgery Checklist implementation in a national sample of 42 general acute care hospitals in a leading hospital network. We measured perceived management practices among managers (n = 99) using the World Management Survey. We measured perceived preoperative safety and safety culture among clinical operating room personnel (N = 2,380 (2016); N = 1,433 (2017)) using the Safe Surgical Practice Survey. We collected data in two consecutive years. Multivariable linear regression analysis demonstrated a significant relationship between changes in management practices and overall safety culture and perceived teamwork following Safe Surgery Checklist implementation.

The aim of this research is to analyze empirical evidence of the effect of governance structure (GS) on perceived success of the succession process. It is also reported that in India, family firms have a more informal organization structure and governance and have an informal and unplanned approach to bringing the successors into family business. Previous studies have reported that GS is an important factor for a successful succession process. This study examines the role of management succession planning as an intervening variable to achieve perceived success of the succession process.

Data have been collected using a questionnaire schedule with 113 respondents who are successors from family business firms in Kerala, India. The study uses snowball sampling technique. Partial least square-structural equation modeling has been used to do data analysis.

The results of the study showed that GS has a significant positive effect on the success of the succession process. GS has a significant positive effect on management succession planning. Management succession planning partially mediates the relationship between GS and perceived success of the succession process.

The results of the study indicate the effect of GS on the relationship between, perceived success of the succession process and management succession planning. The mediating role of management succession planning in the above relationship is also confirmed. Therefore, before starting the succession process a good GS should be put in place for ensuring the success of the succession process. Family firms must implement the succession plan well to make the succession process successful.

The main contribution of the study is to empirically investigate the effect of GS and management succession planning to enhance the success of the succession process.

This study aims to explore the factors influencing electrical accidents. Here, the authors aim to understand and model the causes of electrical accidents at multiple levels.

In the study, the authors have tried to put causes of accidents in the electricity distribution segment, in the framework of the Swiss Cheese model. Delphi kind of expert survey was conducted to find the Cheese Slice (level) and the causes (holes) for electrical accidents. Inputs from a hundred experts having more than five years of experience in electrical utility companies have been used to find Cheese Slice and holes, to explain the occurrence of an electrical accident.

Effective training for safe work practices, safe knowledge and closer supervision would go a long way to plug the holes in the Cheese Slice in human factors. The difference in perception of managers, supervisors and workers on the importance of various causes of electrical accidents are also presented and discussed.

This research is based on expert opinion and survey where respondent perception is reported. Actual accident data has not been used here.

The holes or causes of accidents at different levels (Cheese Slice) have been identified for plugging or removal for better safety.

Electrical energy is widely used, and therefore, electrical safety is a social concern and also improving it is a social need.

The study contributes to electrical safety issues in the electrical utility sector.