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Over the past years, researchers have touched each wave successfully and significant advancement have been introduced in the field of ball bearing. But yet some major aspects of ball bearings need to be divulged like operating radial clearance. The performance and life of the ball bearing significantly depend on its operating clearance. To explore this interest 6206 single row deep groove ball bearing with variable radial clearance is considered in this article. The article basically pacts with the load deformation relationship of variable clearance ball bearing subjected to pure axial load. A closed form solution for load shared by balls is developed using mechanics of solids approach of Hertz contact theory. The acquired result show that under pure axial loading the ball with minimum radial clearance will support maximum axial load. Further, the load shared by 0th ball for variable clearance ball and constant clearance ball bearings is compared. The results and other excerpts from the recommended work will help in unveiling the behavior of ball bearings with variable clearance for combined radial, axial, and moment load. [ABSTRACT FROM AUTHOR]

The post‐earthquake recovery of a community depends on the ability of important buildings to perform their functions. Lifeline and other critical buildings that meet a predictable enhanced seismic performance increase the community's disaster risk management capacity. In prescriptive force‐based design standards, the seismic design force for these buildings is typically enhanced using an importance factor depending on the risk category. The present paper proposes an innovative framework based on performance‐based seismic design (PBSD) principles using risk‐targeted importance factors suitable for use with prescriptive standards. The framework decouples probabilistic assessments of building typologies to experts, while the structural designers can continue the conventional design approach. The framework explicitly considers probabilistic seismic demand, uncertainty in the performance of the building, and the inter‐building variation within a particular building typology in seismic performance. Six special reinforced concrete (RC) frame buildings conforming to Indian standards are selected to illustrate the framework. Sensitivity studies on parameter selection are used to establish the framework's robustness. An expression for the importance factors is also proposed. The use of the proposed importance factor expression is shown to meet a wide range of risk targets corresponding to different performance levels. The paper also proposes design factors for enhanced performance objectives suitable for the risk‐targeted prescriptive design. Further, the framework is implemented to estimate the seismic risk associated with existing building typology conforming to prevalent design standards. The assembly‐ and critical‐category RC buildings are found to require higher importance factors for achieving enhanced performance objectives than currently prescribed. [ABSTRACT FROM AUTHOR]

Built infrastructure systems must be resilient to disasters. After a disaster, its functionality has to evolve with significant uncertainties to restore pre-event condition. Innovative infrastructure design and management pathways can aid in sequencing possible pre- and post-disaster actions, incorporating flexibility into planning and decision-making to enhance resilience. Adoption of disaster risk reduction policies can benefit from accurate, comprehensive, and systematic probabilistic risk and resilience assessments. Such assessments, though not widely prevalent, help to understand the root causes of vulnerabilities and quantify their uncertainties. Therefore, they are prerequisites to identify and implement adaptation pathways for enhancing infrastructure resilience. To support identification and implementation of pathways approach, this study presents seismic resilience assessment incorporating functionality loss and pathways for subsequent recovery. An archetypical reinforced-concrete building, representing typical behavior of the building group used for critical functions, is considered under pre- and post-disaster preparedness, planning, and risk reduction options to develop deeper understanding of risks and selection of pathways. Resilience assessments are conducted based on performance-based earthquake engineering approach and considering uncertainties through Monte Carlo simulations. Both engineering and management interventions, such as improving non-structural component performance, eliminating post-disaster impedances, reducing repair delays, other management activities, and their combinations, are simulated under a common framework. The study quantifies how these measures can reduce losses, improve response, and enhance infrastructure resilience. Options for technical and management decision-making by various stakeholders to enhance resilience are also presented. The study advocates embracing the resiliency mindset and illustrates the benefits of multiple stakeholders for risk-informed decision-making. [ABSTRACT FROM AUTHOR]

Clearance in ball bearing influences the startup torque and stiffness of bearing and affects the load distribution, load carrying capacity, and life of bearing. The present work is related to deep groove single row ball bearing with their rings groove are in a radial plane and the outer ringway track is made elliptical. During this event clearance along the bearing's circumference, rings are no longer constant and vary along with the major to the minor axis. A detailed mathematical model is developed to analyze the performance characteristics of a deep groove single row 6206 ball bearing with variable clearance. Based on Hertz elastic contact theory and contact mechanics, the radial load distribution by balls is calculated. The obtained results and other excerpts of this proposed work open the ground to study ball bearing behavior with variable clearance and its suitability in the field of bearing. The results are further compared with conventional ball bearings and found that the load shared by most loaded ball with variable clearance reduced significantly under the particular angular movement of the outer elliptical ring. Therefore the radial load carrying capacity of ball bearing can be enhanced with variable clearance. [ABSTRACT FROM AUTHOR]

The aim of the present study was to establish the influence of organic selenium and a yeast, Saccharomyces cerevisiae, in combination on animal performance, physiological status, milk production and blood metabolites in indigenous and crossbred dairy cows during hot-humid climatic conditions in tropics. A total of 18 indigenous dairy cows and 18 crossbred dairy cows were divided into two groups(control and treatment) containing 9 cows each based on parity and milk yield for a period of 45 days. The control group were fed on a basal diet comprising a concentrate mix, wheat straw, and multi-cut sorghum greens, while the treatment group were offered basal rations supplemented with organic selenium (4 g/d) along with Saccharomyces cerevisiae (1010 CFU/g; 4 g/d). There were no significant changes found in feed intake, body weight and animal physiology; however, better feed efficiency was recorded in both of the treatment groups, irrespective of breed variation. There was a non-significant increase in milk yield recorded in both treatment groups in comparison with the control. Similarly, no significant effects were observed on the haemato-biochemical profile in both animal types. Hence, it can be concluded that the supplementation of organic selenium and probiotics in combination to indigenous and crossbred dairy cattle moderately improved feed efficiency and overall performance without affecting metabolic status under heat stress conditions in the tropics. [ABSTRACT FROM AUTHOR]