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The purpose of this paper is to present the effect of the preload on the static characteristics of three-lobe bearings lubricated with a fluid blended with high polymer additives modeled as a couple stress fluid.

Based on the micro-continuum theory, the modified Reynolds equation for couple stress fluids is solved using a finite difference method to obtain the distribution of the pressure, the load-carrying capacity, the attitude angle, the friction coefficient and the side leakage for various values of the couple stress parameter and the preload factor.

The results show that the presence of a couple stress in the lubricants improves the static characteristics of this type of bearing compared to those lubricated with Newtonian fluids for any value of the preload factor. Thus, it is found that the preload significantly affects the performance of the three-lobe journal bearing lubricated with a couple stress fluid or a Newtonian fluid. Moreover, the investigation showed that increasing the preload factor exhibits an increase in the load carrying capacity and the attitude angle, but it decreases the friction coefficient and the side leakage especially at a lower preload factor. Furthermore, using a couple stress fluid and a higher preload factor led to a significant rise in the load carrying capacity and a significant reduction in the friction coefficient.

This study helped improve the performance characteristics of the three-lobe journal bearing.

The presence of couple stress in the lubricants improves the static characteristics of this type of bearing compared to those lubricated with Newtonian fluids for any value of the preload factor. The usage of the couple stress fluid and the higher preload factor led to a significant rise in the load carrying capacity and a significant reduction in the friction coefficient.

The purpose of this paper is to study the effect of liner surface texture on journal bearing performance. Modeling the profile curvature of the dimples or grooves is planned for different cases of texture surface under thermo-hydrodynamic condition (THD). The aim of this paper is to determine the effect the texture surface on the performance of journal bearing and specify the optimum shape for texture dimples.

The paper was opted for an exploratory study by applying finite difference method to solve the energy equation, the heat conduction equations and the Reynolds equation numerically. The lubricant film thickness is divided to a mesh of 640,000 points. The equations were solved for each point of the mesh by using a MATLAB code. For texture shape optimization, 24 cases of different texture shapes were selected which includes elliptical, triangle and square curvature shape.

The paper provides theoretical insights about the effect of texture shape on journal bearing performance. It was concluded that to get a high load-carrying capacity, the direction of curvature is preferably to be perpendicular to the sliding direction. The convex texture has higher load carrying capacity than concave texture. Finally, the surface with textures in channel form yields better overall performance than the surface with several dimples.

This paper fulfils an identified need to study how texture surface affects the performance of journal bearing under thermo-hydrodynamic conditions.

This paper aims to provide an assessment of the quality of management practices and implementation in hospitals operating in the West Bank of Palestine using the Malcolm Baldrige National Quality Award (MBNQA) Criteria.

Based on the MBNQA Criteria, a survey of 51 hospitals was conducted using questionnaires, interviews and focus groups to gather data. Data were analyzed and compared across all administrative types of hospitals using the MBNQA points system.

The results show that the performance of non-governmental organizations and private hospitals was superior with respect to all other administrative types. A closer look at the results show that all hospitals exhibit areas of concern such as human resource focus, information and analysis, as well as performance results.

Despite the exclusion of hospitals operating in the Gaza Strip, this research promotes critical management practices aimed at improving quality of management practices and their subsequent implementation in the surveyed hospitals.

The MBNQA Criteria, as well as other quality assessment tools, can be used to measure the various activities of hospitals and identify competencies and weaknesses in a tangible manner to improve hospital performance.

This paper presents a fresh perspective on the quality management issues in Palestinian hospitals to practitioners, administrators and academics using the MBNQA Criteria. Also, it serves as a foundation for future initiatives and programs aimed at improving quality in hospitals.