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Measurements of fluid film pressures were made on water-lubricated rubber journal bearings. The measurements indicated that the film pressure profiles are very different from those of conventional rigid bearings. The relatively low film pressures caused significant rubber deflections but were too low to produce lubricant viscosity changes. Integration of the pressure in the bearings showed that they operate in the regime of mixed lubrication. The behaviour of the bearings was theoretically investigated using computational fluid dynamics. There was reasonable agreement between computational fluid dynamics and experimental results.

Plesiosaurs are an enigmatic, diverse extinct group of Mesozoic marine reptiles well-known for their unique body plan with two pairs of flippers and usually an elongated neck. The long neck evolved several times within the clade, yet the evolutionary advantages are not well understood. Previous studies have mainly focused on swimming speeds or flipper locomotion. We evaluated the hydrodynamics of neck length and thickness in plesiosaurs using computational fluid dynamics (CFD) simulations based on the Reynolds-Averaged Navier-Stokes (RANS) approach. Simulations were performed of flow patterns forming around five distinctive plesiosaur models, three of different neck lengths (neck/body ratios of 0.2, 0.41, and 0.63) and two of different neck thicknesses (100% and 343% increase compared to cervical vertebrae width). By simulating water flow past the three-dimensional digital plesiosaur models, our results demonstrated that neck elongation does not noticeably affect the force of drag experienced by forward swimming plesiosaurs.Thicker necks did reduce drag compared with thinner necks, however. The consistent drag coefficient experienced by the three neck lengths used in this study indicates that, at least for forward motion at speeds from 1-10m/s, hydrodynamic implications were not a limiting selective pressure on the evolution of long necks in plesiosaurs. We also tested the effects of bending the long neck during forward motion. Bending a plesiosaur neck evenly in lateral flexion increased the surface area normal to flow, and subsequently increased drag force. This effect was most noticeable in the longest necked forms.

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The upper airway models closely simulated the in vivo deposition data. Optimizing the upper airway posture during inhalation via the nebulizers would be more efficient in increasing drug lung delivery than diluting their contents.

The grinding power is often used as a parameter for monitoring the grinding process. The power may also be used to monitor the effects of dressing. Empirical models are required to guide the selection of the dressing and grinding conditions. In this paper, the effects of dressing conditions and grinding conditions on grinding force and grinding power are reviewed. The effects of grinding conditions and dressing conditions on grinding force and grinding power are related to the shape of the idealized chip thickness. It is found that the grinding force and grinding power can be related to the dressing operation by considering the effective density of the cutting edges on the wheel surface. The semi-empirical model developed in this paper can be used to predict the variation of the grinding power during the wheel redress life cycle. Therefore the model can be used to guide the selection of dressing and grinding conditions. The potential use of the model for adaptive control of the grinding process is also described.

In modern competitive manufacturing industry, machining processes are expected to deliver products with high accuracy and assured surface integrity, using shorter cycle times with reduced operator intervention and increased flexibility. To meet such demands, the trend towards increased use of machine intelligence in machining systems and operations is clear and unlikely to be revised. This paper describes the structure, content and relations employed in a fully integrated intelligent grinding system for adaptive controlled cycle optimisation, thermal damage avoidance, dressing interval optimisation and data retention. This system, termed: 'Intelligent Grinding Assistant' (IGA©) is a unique, robust and versatile software system with embedded links and protocols for communication with the Computer Numerical Control (CNC) and instrumentation of a grinding machine. The IGA© was evaluated and implemented on a commercially available production machine and had its international launch in September 2005. The CNC, machine tool instrumentation, process monitoring and data analysis systems, Profibus link, and control strategies all constituted the IGA© system. Grinding performance was monitored and assessed in real time. An intelligent database was also developed to support the IGA© in the provision of optimised and/or safe starting cycle data to the operator/adaptive system and in the selective Design and implementation of an intelligent grinding assistant system 107 retention of data. Importantly, the IGA© has been designed and implemented in a way to ensure that an operator can readily use the system and achieve process improvement without recourse to extensive training.

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