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Bearings are critical components used to support loads and facilitate motion for rotating and sliding parts of the machinery. Bearing malfunctions can cause catastrophic failures. Hence, failure analysis and endeavors to improve bearing performance are essential discussions for worldwide designers, manufacturers and end users of vital machinery. This study aims to investigate a type of roller bearing from the railway industry with premature failures. The task arises because locomotives’ maintenance and service life quality are vital to railway operations while providing transportation services for the nation. To assist in maintaining the designated locomotives, the present study scrutinizes the causes of failure of heavy-duty roller bearings from locomotive bogie axleboxes.

It is intended to inspect this bearing service life and statistically scrutinize its design parameters to reveal the failures’ shortcomings and origins. The significant measures include examinations of their failures’ primary and vital factors by comparing them with a real-life service history of 16 roller bearings of the same type. The bearings come from the axleboxes of a locomotive bogie with an axle load of 20 tons. The bearing loads are estimated using the EN13104 standard document and confirmed by the finite element method using ABAQUS engineering software. To validate the finite element modeling results, the bearings’ stress analysis is performed using the Hertzian contact theory that demonstrated perfect conformity. The said methods are also used to search for the areas susceptible to failures in these bearings. With the inclusion and exploitation of the bearing maintenance conditions and the logbook recordings of the locomotives for the past seven years, the critical cause for this type of bearing’s failures is surveyed and discussed.

With the inclusion and exploitation of the bearing maintenance conditions and the logbook recordings of the locomotives for the past seven years, the critical cause for this type of bearing’s failures is surveyed and discussed. As a crucial result, it is found that deprived maintenance and inadequate lubrication are the root causes of the loss of the selected bearings.

For the designated locomotives, the origins of the heavy-duty roller bearing failures and its design shortcomings are revealed by examining and comparing them with a real-life service history of many of the same types of bearings. The novelty of the research is in using the combination of the methods mentioned above and its decent outcome.

Although online social networks (SNs) (e.g. Facebook, LinkedIn and Instagram) have been used by employees for various work- or non-work-related motives, there has been lack of research on the use of such networks in the workplace. The purpose of this paper is to draw on commitment theory and the tricomponent attitude model to explain the role organisational commitment plays in predicting the work-related use of online SNs and the mediating role a constructive employee voice may have in this relationship.

The research was conducted among the employees of seven different companies within seven different industries. The validity of the measures and structural models was evaluated using partial least squares structural equation modelling (PLS-SEM).

The results indicated that organisational commitment promotes employees’ work-related use of online SNs directly and also indirectly via the mediating role of a constructive voice.

This study is among the few studies which have used the tricomponent attitude model to investigate employees’ behaviour in the workplace, in particular work-related use of online SNs. In terms of theory, this study contributes to expanding the boundaries of knowledge as SNs are considered a challenge in contemporary organisations. Organisations can convert this challenge from a potential threat to an actual opportunity by reinforcing “organisational commitment”.

This study, based on the cognitive dissonance and commitment theories, aims to show that employees with high organizational commitment take more advantage of enterprise social networks (ESNs) due to work-related motivations. Furthermore, this study used the tricomponent attitude model to show that the employees' organizational concern and prosocial values mediate the impact of the organizational commitment on the work-related use of an ESN.

In all, 361 employees from seven Iranian companies using different ESN software packages were surveyed. The validity of the hypotheses was evaluated using partial least square–structural equation modeling (PLS-SEM).

The results of this study confirm that the employees' organizational commitment has a positive impact on their work-related use of the relevant ESN directly and through the mediating roles of their organizational concern and prosocial values.

Previous studies have carefully addressed the role of organizational commitment in the implementation of conventional information systems. However, this is among the few studies addressing the role of commitment in the work-related implementation of ESNs. The results of this study shed light on how employees with a high level of commitment toward the organizations for which they work take advantage of ESNs due to a work-related motivation for the accomplishment of their duties, for bringing benefits into the organization and for helping their coworkers.

The purpose of the study is to ascertain the role of servant leadership in causing innovative work behavior. The study also examines the mediating role of job crafting and sequential mediating role of trust and job crafting between servant leadership and innovative work behavior.

The data were collected from 258 knowledge workers employed in software houses in Pakistan through survey design. The data analysis was done through structural equation modeling.

The results of the analysis of 258 respondents show that servant leadership is related with trust, job crafting and innovative work behavior. The mediation analysis revealed that job crafting mediates the relation between servant leadership and innovative work behavior. Finally, the relation between servant leadership and innovative work behavior was found to be sequentially mediated by trust and job crafting.

The current study contributes to delineating the linking mechanism between servant leadership and innovative work behavior. The main contributions of the study are exploring the mediating role of job crafting along with the sequential mediating role of trust and job crafting.

Public–private partnerships (PPPs) are notoriously prone to disputes among stakeholders, some of which may unduly jeopardize contract performance. Contract disputes arising in Iran are often due to inefficiency of PPP concession agreements and practice. This study presents a causal-predictive model of the root causes and preventive measures for inter-organization disputes to enhance the likelihood of achieving desirable performance in PPP projects.

A theoretical “causal-predictive” model was developed with fourteen hypotheses based on extant literature and contractual agency theory, which resulted in the creation of a pool of 110 published items. Data were obtained from a questionnaire survey with 75 valid responses, completed by 4 stratified groups of Iranian PPP experts. Partial least square structural equation modeling (PLS-SEM) was used for validating the proposed model via a case study.

Results reveal that the main three factors of PPP desirable performance are as follows: on-time project completion, high quality of activities/products and services for public satisfaction. Further, the most influential factors of the lifecycle problems, construction stage, and preferred risk allocation included risk misallocation, improper payment mechanism and failure to facilitate a timely approval process.

For researchers, the findings contribute to the theory of contractual agency; specifically, how different influences among the model's elements lead to better PPP performance. In practical terms, proposed outcome-based strategies will inform PPP stakeholders to avoid dispute occurrence and thus improve the time, quality and services of projects.

The purpose of this paper is to empirically demonstrate how knowledge management, particularly knowledge integration (KI), acts as a mediator in enterprise systems (ES) post-implementation stage and how transactional and transformational leadership styles are impacted toward ES success.

Drawing on the insights of 508 valid respondents from various business backgrounds that used ES in Malaysia, structural equation modeling was employed and the path modeling approach was used to investigate the underlying relationships between variables. The mediating effects were tested using the bootstrapping procedures presented by Preacher and Hayes.

The results support the mediating effects of KI mechanisms and both leadership styles toward ES success. The analysis revealed the importance of KI in an organization, especially by the leaders who manage the complexity of the ES in the post-implementation stage.

The study can be extended by analyzing other leadership styles in-detail.

This paper is useful for practitioners as it acts as a guide to conduct management practice for business managers.

The results demonstrate the importance of leaders’ adoption of KI mechanisms in various business domains. This study approach can be used to investigate which sub-items of the leadership styles are more likely to promote KI mechanisms.

The quality of people life and efficiency of banks can be improved by mobile banking (m-banking). The long-term success of m-banking depends on its constant use. The purpose of this paper is to investigate the determinants of m-banking continuance intention to use, using the technology continuance theory (TCT) by including the self-efficacy and channel preference.

Empirical data from 369 Malaysian users who had prior experience with mobile banking were analysed, using partial least squares technique.

The results confirmed that the TCT model had a high exploratory power in explaining users’ perceived usefulness (PU), satisfaction, attitude and intentions to continue to use m-banking. Furthermore, self-efficacy and channel importance were important drivers of continuance intention in the context of m-banking. According to the results, perceived ease of use has no effect on PU and attitude in the post-adoption stage.

The findings help bank managers to understand the importance of meeting customers’ needs and expectations as a prerequisite in enhancing their satisfaction and favourable attitude towards m-banking and consequently their continuance intention.

Based on the TCT model, this study contributes to the limited body of research on continuance intention to use m-banking. Furthermore, self-efficacy and channel preferences were added to the TCT model and the results confirmed the importance of enriching the TCT model to explain continuance intention to use information systems by adding contextual factors.

The purpose of this paper is to provide an overview of the antimicrobial and antioxidant properties of postbiotics and the use of postbiotics to increase the shelf life and quality of food.

In this review paper, all articles from five electronic databases containing Google Scholar, Web of Science, PubMed, Scopus and Science Direct were considered and selected according to the purpose of the study.

In addition to improving food safety and increasing its shelf life, natural food preservation using biological preservatives also has a positive effect on improving consumer health. As a result, protection using natural antioxidants and antimicrobial agents seems essential. Postbiotics, having favorable characteristics such as nontoxicity, long shelf life and ease of standardization and transportation, are known as suitable antioxidant and antimicrobial, and there is an interest in making antioxidant and antimicrobial active films containing postbiotics to delay spoilage, increase the shelf life of perishable foods without changing their sensory characteristics.

Postbiotic refers to all soluble factors that are either secreted from living probiotic cells or released after cell lysis. These compounds include enzymes, peptides, polysaccharides, organic acids, teichoic acids and cell surface proteins, and their effects have been proven to improve some human and animal diseases. Probiotic bacteria must survive unfavorable conditions such as processing, storage, distribution, preparation and the digestive system to exert their health-giving effects, whereas their metabolites (postbiotics) have overcome these adverse conditions well and may be a good substitute for probiotics.

In traditional Bayesian belief networks (BBNs), a large amount of data are required to complete network parameters, which makes it impractical. In addition, no systematic method has been used to create the structure of the BBN. The aims of this study are to: (1) decrease the number of questions and time and effort required for completing the parameters of the BBN and (2) present a simple and apprehensible method for creating the BBN structure based on the expert knowledge.

In this study, by combining the decision-making trial and evaluation laboratory (DEMATEL), interpretive structural modeling (ISM) and BBN, a model is introduced that can form the project risk network and analyze the impact of risk factors on project cost quantitatively based on the expert knowledge. The ranked node method (RNM) is then used to complete the parametric part of the BBN using the same data obtained from the experts to analyze DEMATEL.

Compared to the traditional BBN, the proposed method will significantly reduce the time and effort required to elicit network parameters and makes it easy to create a BBN structure. The results obtained from the implementation of the model on a mass housing project showed that considering the identified risk factors, the cost overruns relating to material, equipment, workforce and overhead cost were 37.6, 39.5, 42 and 40.1%, respectively.

Compared to the traditional BBN, the proposed method will significantly reduce the time and effort required to elicit network parameters and makes it easy to create a BBN structure. The results obtained from the implementation of the model on a mass housing project showed that considering the identified risk factors, the cost overruns relating to material, equipment, workforce and overhead cost were 37.6, 39.5, 42 and 40.1%, respectively. The obtained results are based on a single case study project and may not be readily generalizable.

The presented framework makes the BBN more practical for quantitatively assessing the impact of risk on project costs. This helps to manage financial issues, which is one of the main reasons for project bankruptcy.

The purpose of this paper is to introduce an integrated approach using failure modes and effects analysis (FMEA), multiple-criteria decision making (MCDM), mathematical modeling and quality function deployment (QFD) techniques, for risk assessment and service quality enhancement in coronary artery bypass grafting (CABG) as a treatment for cardiovascular diseases (CVDs).

First, the disruptions in the CABG process are identified and prioritized following FMEA instructions, using two MCDM techniques, called analytic hierarchy process (AHP) and TOPSIS. Consequently, several corrective activities are identified and weighted on the basis of QFD. Finally, a mathematical model is established to determine the most cost-effective activities for implementation. The approach is developed in a fuzzy environment to reflect the uncertainty and ambiguity of human reasoning.

Regarding the CABG process disruption, a total of 30 failure modes in four main categories were identified and prioritized. Moreover, eight corrective activities were devised and ranked according to their impact on the failure modes. Finally, considering a limited amount of budget, a sensitivity analysis on the mathematical model’s objective function indicated that using 30 percent of the total budget, required to implement all corrective activities, was enough to cover more than 70 percent of the effects of corrective activities on the failure modes.

This paper contributes to the quality risk assessment knowledge by introducing an integrated approach to evaluate and improve healthcare services quality. Also, the case study conducted on the CABG process has not been done by other related studies in the literature.