A solution is proposed to the estimation of upper-limb orientation using miniature accelerometers and gyroscopes. This type of measurement device has many different possible applications, ranging from clinical use with patients presenting a number of conditions such as upper motor neuron syndrome and pathologies that give rise to loss of dexterity, to competitive sports training and virtual reality. Here we focus on a design that minimizes the number of sensors whilst delivering estimates of known accuracy over a defined frequency range. Minimizing the sensor count can make the measurement system less obtrusive, as well as minimising cost and reducing the required bandwidth if using a wireless solution. Accurate measurement of movement amplitude up to 15 Hz is required in our immediate application, namely to quantify tremor in multiple sclerosis patients. The drive for low numbers of sensors and good accuracy at higher frequencies leads to a novel design based on composite filters. The simple estimator structure also gives good insight into the fundamental accuracy limitations based on the sensors chosen. This paper defines the underlying mathematics, and quantifies performance for an estimator for shoulder, upper arm, lower arm and hand orientations. Good estimation accuracy up to 15 Hz is indicated, and this with a reduced total sensor count of 18 compared to 24 that would be required for more conventional estimator architectures.

The aim of this study was to compare the measured effectiveness of an air curtain device at different jet velocities against a three-dimensional (3-D) computational fluid dynamics (CFD) model. The air curtain device was not as wide as the entrance and had a geometry that encouraged 3-D flow. By carefully setting up the air curtain an effectiveness of 0.71 was achieved compared to the initial value of only 0.31 as set by the air curtain device installer. The 3-D CFD model predicted the infiltration through the entrance with no air curtain to an accuracy of within 20-32%. The predicted effectiveness, E, of the air curtain at different jet velocities was 0.10-0.15 lower than measured. The shape of the effectiveness curve against jet velocity was well predicted. CFD has shown that the flow from this air curtain cannot be considered as 2-D. The central part of the jet is deflected away from the cold store by the Coanda effect caused by the air curtain device's fan body. The edges of the jet are deflected into the cold store by the stack pressures and turn into the void caused by the deflected central jet. (c) 2006 Elsevier Inc. All rights reserved

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11The majority of data relating heat treatments to thermal death kinetics has previously been obtained by carrying out in vitro tests 12 on small samples of microorganisms in growth medium or food slurries. However, strong evidence exists that suggests microbial 13 death on heat-treated food surfaces cannot be predicted accurately from such systems. An apparatus was therefore designed to 14 enable microbial death on food surfaces to be quantified. 15The apparatus uses hot air to provide a ÔdryÕ heat treatment to raise the surface of a food sample to a given temperature, up to 16 100°C, hold and then cool it. The surface temperature was measured using an infra-red (IR) thermometer and the air heater was 17 controlled to give a specified surface temperature history. Steam was also used to provide a ÔwetÕ, but less controlled heating cycle. 18

This paper reports on work carried out to date, and future directions for, a project that intends to measure and control tremor in individuals with multiple sclerosis (MS). The project will use computer modelling to simulate the movements involved in upper limb intention tremor, as exhibited by individuals with MS.The models will be incorporated into a final system that will interpret measurements from sets of microelectromechanical systems (MEMS) sensors positioned over the surfaces of the upper limb to provide position, orientation and movement information. These data will be combined with gross muscle activity data, extracted from surface electromyogram (EMG) measurements, to create a fully dynamic model of the arm movements in real time. This model will be used to develop methods of attenuating the tremor, firstly at the elbow joint, without adversely affecting the underlying intended movement, by providing real-time feedback control of appropriate force input devices. The estimates of movement and the forces involved will also provide clinicians with a useful tool in the quantification of upper limb tremor.