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The journal bearings subjected to heavy load and slow speed operate in mixed lubrication regime causing contact between the interacting surfaces and resulting in wear. Complexity of wear behavior and lack of unifying theory/model make wear-control very challenging.

In the present research work, theoretical and experimental investigations have been conducted to explore the effect of grooving arrangements on the wear behavior of journal bearing operating in mixed lubrication regime. The theoretical model of Hirani (2005) that uses mass conserving cavitation algorithm has been used to determine the bearing eccentricity for different groove arrangements (with varying groove location and extent) for identifying a groove arrangement that minimizes the wear. The wear tests on the grooved bearings were conducted after suitable running-in of the new bearings on a fully automated journal bearing test set-up. A load and speed combination required to operate the bearing in mixed lubrication was used. The performance of different arrangement of bearing was evaluated by measuring their weight loss after the test.

Wear was significantly reduced with the use of proper groove arrangement for a bearing operating in mixed lubrication regime.

The improvement in bearing performance by providing grooves has been the subject matter of several studies in the past, but these studies were confined to the hydrodynamic operative regime of the bearing. In the present work, seven different combinations of axial and radial groove arrangement were tried, which has not been reported in any other work.

This paper aims to revise the ideal ratio for selecting new products based on their qualitative analysis of desired/undesired functions.

The Kano model has been integrated with the ideal ratio to select and prioritize the design of new products. First, the functional analysis method in value engineering was used to determine the attributes and functions of each product design. Then, the Kano model was used to determine the type of each product attribute and to use the desirable functions of attractive attributes, one-dimensional, must-be and undesirable functions of reverse attributes in the ideal ratio to select and prioritize the design of the product. To examine the application of the proposed approach, a gas instruments manufacturing company was investigated, and five new products were selected for the study.

Based on the results, the product design of industrial regulator GS 77/22 was selected as the superior product and the digital diaphragm gas meter, ultrasonic gas meter, axial regulator and turbine gas meter had the second to fifth priority, respectively.

The proposed method can help product designers determine product designs suitable for customers' expectations and provide a desirable prioritization of the product design in terms of their ideal ratio according to the customers.

The proposed approach provides a more desirable prioritization compared with other prioritization methods based on customers' viewpoints. In the proposed method, the Kano model results in respecting customers, understanding community needs, respecting consumers' rights and increasing the organization's social responsibility, which will significantly increase the chance of product success in the market.

The edge of diesel engine crankshaft main bearing is more likely to fail in its real working condition. This paper aims to study the bearing failure mechanism by finding the relationship between bearing lubrication characteristics and its working condition.

This work builds the mixed lubrication model of crankshaft bearing to analyze the cause of bearing abnormal wear, and the finite difference method was used to solving the average Reynolds equation. During the analysis, journal misaligned angle, external load and roughness are considered.

The result shows that the wear of the diesel engine crankshaft bearing happens in engine startup phase and the bottom of the bearing are more prone to be excessively worn. Under the influence of journal misalignment, bearing asperity contact load and speed range of mixed lubrication will increase markedly. The edge of the bearing will be excessively worn. The effect of misalignment on bearing lubrication performance varies under different shaft rotation speed.

The former research studies on crankshaft bearing either just focused on its lubrication characteristics or interested in its failure types (wear, adhere, cavitation). This paper studies the relationship between bearing failure mechanism and lubrication performance.

The regular occurrence of natural disasters elevates the need for an effective method to measure organizational preparedness in responding to the adverse impact of disasters. In this context, this paper presents a new decision support model to assess organizational disaster preparedness using both subjective and objective disaster preparedness criteria in a multi-criteria decision-making context.

The statistical variance method is integrated with the proximity value index (PVI) technique to determine priority scores in order to rank organizational disaster readiness.

The results of applying the integrated model developed herein enable decision-makers to make informed decisions for assigning priority ranking of organizational disaster preparedness in a simpler and more efficient way.

Human resource is the most impacting criterion affecting hospital preparedness in undertaking action to cure disaster victims.

This paper offers an exemplar of a simple and efficient decision-making process considering the subjectivity associated with decision-making as well as the objectivity of data used for determining the priority ranking of organizational disaster preparedness.

Integrating statistical variance method with the PVI technique is novel and it has not been presented in previous studies. In fact, this study is the first to integrate both methods for selecting the priority ranking of organizational disaster preparedness.

This paper aims to present a numerical model to investigate the mixed lubrication performances of journal-thrust coupled bearings (or coupled bearings).

The coupled hydrodynamic effect (or coupled effect) between the journal and the thrust bearing is considered by ensuring the continuity of the hydrodynamic pressure and the flow field at the common boundary. The mixed lubrication performances of the coupled bearing are comparatively studied for the cases of considering and not considering coupled effect.

The simulated results show that the hydrodynamic pressure distributions for both the journal and thrust bearing are modified due to the coupled effect. The decreased load capacity of the journal bearing and the increased load capacity of the thrust bearing can be observed when the coupled effect is considered. And the coupled effect can facilitate in reducing the asperity contact load for both the journal and thrust bearing. Additionally, the interaction between the mixed lubrication behaviors, especially for the friction coefficient, of the journal and the thrust bearing is significant in the elastohydrodynamic lubrication regime, while it becomes weak in the mixed lubrication regime.

The developed model can reveal the mutual effects of the mixed lubrication behavior between the journal and the thrust bearing.

The current study aimed to develop and validate a scale to model factors affecting digital technology access for instructional use. The scale was mainly used to assess the structural model. Besides, tests of difference were addressed regarding digital technology access for instructional use based on gender, teaching experience and school location.

The authors implemented a survey design in this study. A scale based on prior studies was developed, validated and piloted. The pilot study data were computed for an exploratory factor analysis. Further, partial least squares structural equation modeling (PLS-SEM) and t-test procedures were used for the main data analysis (n.2677). The authors also included the importance-performance map analysis to extend of the results of the PLS-SEM.

The findings of the study successfully assessed the validity and reliability of the scale. All hypothetical relationships in the structural model were positively significant. The t-test results show that teaching experience and school location were significantly different regarding instructional use access; however, an insignificant difference emerged based on gender.

Failure in technology integration is possible if policies have not been carefully prepared. Therefore, users' perception is an essential factor in determining technology integration, including access to digital technology.

This research has the potential to enhance the understanding of access to digital technology in the context of developing countries by the elaboration of the proposed model's instrument development and validation, path analysis assessment and difference test examination with a large sample size. Also, the current study emphasizes the importance of raising awareness about digital technology access that the model can facilitate a valid and reliable foundation for future researchers interested in conducting similar types of research.

The purpose of this paper is to report on the development of magnetorheological (MR) fluids, having high on-state shear stress/viscosity, low off-state shear stress/viscosity, good redispersibility and stable suspension of carbonyl iron particles, using tetramethyl ammonium hydroxide (TAH) and oleic acid.

MR fluids for use in brakes are synthesized using different weight percentages of silicone oil, TAH, oleic acid and iron particles. The effects of TAH and oleic acid are studied. Shear stress is measured as a function of magnetic field on a magneto-rheometer. The images of MR particles settling with time are presented. The test set-up used to evaluate the performance of the MR fluids synthesized for brake application is detailed. Finally, a significant improvement in the MR performance of brakes is reported.

The MR fluid having 0.25 Wt.% oleic acid showed low off-state viscosity/shear stress and high on-state viscosity/shear stress. A higher weight percentage of TAH in the MR fluid further reduced the low off-shear stress and increased the high on-state shear stress with better stability.

Improvement of MR brake performance by adding surfactants like TAH and oleic acid has been the subject matter of several studies in the past, but these studies used a fixed percentage of surfactants in MR fluids. In the present work, the optimum percentage of TAH and oleic acid for an improved braking performance is determined by varying their content in the MR fluid, which has not been reported in any other work thus far.

The purpose of this study is to construct a gray relational model based on information diffusion to avoid rank reversal when the available decision information is insufficient, or the decision objects vary.

Considering that the sample dependence of the ideal sequence selection in gray relational decision-making is based on case sampling, which causes the phenomenon of rank reversal, this study designs an ideal point diffusion method based on the development trend and distribution skewness of the sample information. In this method, a gray relational model for sample classification is constructed using a virtual-ideal sequence. Subsequently, an optimization model is established to obtain the criteria weights and classification radius values that minimize the deviation between the comprehensive relational degree of the classification object and the critical value.

The rank-reversal problem in gray relational models could drive decision-makers away from using this method. The results of this study demonstrate that the proposed gray relational model based on information diffusion and virtual-ideal sequencing can effectively avoid rank reversal. The method is applied to classify 31 brownfield redevelopment projects based on available interval gray information. The case analysis verifies the rationality and feasibility of the model.

This study proposes a robust method for ideal point choice when the decision information is limited or dynamic. This method can reduce the influence of ideal sequence changes in gray relational models on decision-making results considerably better than other approaches.

The purposes of the present study are to ensure higher sustainability of journal bearings under different applied loads and to observe bearing performances such as elastic strain, total deformation and stress formation.

A journal bearing test rig was used to determine the effect of the applied load on the bearing friction, film thickness, lubricant film pressure, etc. A steady-state analysis was performed to obtain the bearing performance.

An efficient aspect ratio (L/D) range was obtained to increase the durability or the stability of the bearing while the bearing is in the working condition by using SAE 5W-30 oil. The results from the study were compared with previous studies in which different types of oil and water, such as Newtonian fluid (NF), magnetorheological fluid (MRF) and nonmagnetorheological fluid (NMRF), were used as the lubricant. To ensure a preferable aspect ratio range (0.25-0.50), a computational fluid dynamics (CFD) analysis was conducted by ANSYS; the results show a lower elastic strain and deformation within the preferable aspect ratio (0.25-0.50) rather than a higher aspect ratio using the SAE 5W-30 oil.

It is expected that the findings of this study will contribute to the improvement of the bearing design and the bearing lubricating system.

This paper aims to explore different forms and models of integration between Islamic commercial finance and social finance including the problem that arise as well as the solution of each of the models to promote inclusive economic growth. At the end of the paper, the authors have identified the strategy to execute and validate by the decision-makers.

This approach uses two methods which are Delphi and analytical network process (ANP). The authors conduct literature review and four rounds Delphi to construct the integration model, the problem and solution of each model, as well as the questionnaire of ANP. Moreover, using an ANP method, the authors conducted interviews with decision-makers in the areas of Islamic commercial finance as well as social finance, and analyzed the results to identify key models that would create inclusivity and quality of economic growth. To ensure credibility of the results, the authors selected the respondents based on their experience in the fields, as well as their unique perspectives that will complement the group as a whole.

After conducting the four rounds Delphi, the authors found five types of Islamic social and commercial integration which are the ownership, institutional, operational, bottom line and mandatory integration. Based on the analysis of the ANP result, the authors argue that all integration can help the country in attaining with the support of government in terms of making the integration as a vision as well as to push the education of social finance more to the stakeholders.

This study is among the emerging studies that explore operational aspects of integration of social and commercial finance within the context of inclusive growth strategy.