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Exoskeleton devices are being introduced across several industry sectors to augment, amplify, or reinforce the performance of a worker's existing body components—primarily the lower back and the upper extremity. Industrial exoskeletons may play a role in reducing work‐related musculoskeletal disorders arising from lifting and handling heavy materials or from supporting heavy tools in overhead work. However, wearing an exoskeleton may pose a number of risks that are currently not well‐studied. There are only a few studies about the safety and health implications of wearable exoskeletons and most of those studies involve only a small number of participants. Before the widespread implementation of industrial exoskeletons occurs, there is need for prospective interventional studies to evaluate the safety and health effectiveness of exoskeletons across various industry sectors. Developing a research strategy to fill current safety and health knowledge gaps, understanding the benefits, risks, and barriers to adoption of industrial exoskeletons, determining whether exoskeleton can be considered a type of personal protective equipment, and advancing consensus standards that address exoskeleton safety, should be major interests of both the occupational safety and health research and practice communities. [ABSTRACT FROM AUTHOR]

Molecular and Brownian dynamics simulations are used to investigate the frequency-dependent dielectric relaxation of ferrofluids, with the objective of identifying features characteristic of dipolar chain formation at low densities. It is shown that the presence of chains gives rise to a high frequency band associated with the vibrational motion of dipoles within the chains. This band serves as a “signature” of association and is not present in dipolar fluids at higher, liquid-like densities. A simple theory that traps the basic features of the relaxation behavior is also presented. © 2002 American Institute of Physics. [ABSTRACT FROM AUTHOR]

A new modified conductivity model was established to predict the shear yield stress of electrorheological fluids (ERF). By using a cell equivalent method, the present model can deal with the face-center square structure of ERF. Combining the scheme of the classical conductivity model for the single-chain structure, a new formula for the prediction of the shear yield stress of ERF was set up. The influences of the separation distance of the particles, the volume fraction of the particles and the applied electric field on the shear yield stress were investigated. [ABSTRACT FROM AUTHOR]

Presents an apparatus for thermal diffusivity measurement of particulate materials at subambient temperatures. Theory of modulated heat flow in a cylindrical cell; Description of the thermal conductivity apparatus; Applications of the instrument.

The influence of rotating fields on strongly interacting dipolar fluids is investigated using molecular dynamics and Brownian dynamics simulations. Both one-component and two-component systems are considered. It is shown that under certain conditions rotating fields can induce spatial layering in these systems. This behavior is similar to that recently observed in experimental studies of electrorheological and magnetorheological fluids. The binary mixture results are particularly interesting. It is shown that components that differ only in their moments of inertia can be separated by adjusting the frequency of the applied field. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]