Many types of techniques for metering the mass flow rate of bulk solids in a pneumatic pipeline have been proposed and developed during the past 20 years. This paper presents a detailed and comprehensive review of the techniques and the current state of knowledge and experience. The techniques are classified under three main categories: direct measurement of solids mass flow rates, measurement of volumetric concentrations of solids and measurement of solids velocity. Future developments and possible trends in this field are also included.

Theoretica and expermental studies of cross conelation techniqJes appliea io non-resrrictive velocity measuement of pneumatically conveyed solids using ringshaped electrodynamic flow sensors are presentea. In-deptn studies of the electrodynamic sensing mechanism, and also of the spat al sensitivity and spatial filtering propenies of the sensor are incldded, together with heir relationships to measurement accuracy and the effects of solids' velocity prof:les. The experimental evaluation of a 53 mm bore sensing head is descr bed, ncluding tnals us.ng a calibrated pneumatic conveyor circLlat ng pulverized fuel and cement. Comparisons of test results with the mathematcal moaels of the sensor are used to identify important aspects of the instrLment design. OH-line test results obtained using gravity-fed solids flow show that the system repeatab lily :s w.thin -LO.S% over the velocity range of 2-4 m s-' for volumetric concentrations of solids no greater than 0.2%. Results obiained in the pilot-plant tr.als demonstrate that t h e system is capable 01 achieving repeatab.lity better than &2% and linearity wi1h.n 12% over the veloc.ty range 20-40 m s-' for volJmetric concentrations of solids in the range 0.01-0.44%.

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The flicker of a flame is an important physical parameter associated with the characteristics of a combustion process. This paper presents a novel instrumentation system developed for on-line continuous flicker measurements of combustion flames. The system comprises a high-speed CCD camera, a frame grabber and associated image processing software. The flicker signal was obtained by processing the radiation intensity of individual pixels within the luminous region of a flame image. Power spectral density analysis was performed to obtain the frequency components of the flicker signal. The quantitative flicker of a flame is defined in terms of weighted spectral components in the frequency domain and this definition has been proven to be well suited to quantification of the flickering characteristics of a flame. A tungsten lamp driven by a frequency-varying power supply was employed to calibrate the measurement system. The calibration results show that the system is capable of measung the flicker of an unknown light source with a relative error no greater than 3% . The system developed has been utilized to investigate the relationship between the flicker of a diffusion flame and the burner diameter, and to study the effect of the equivalence ratio on the flicker of a premixed flame under a range of combustion conditions. The experimental results obtained by both motion image analysis and spectral analysis have demonstrated that the flicker of a diffusion flame depends predominantly on the burner diameter. It has also been found that the flicker of a premixed flame varies with the equivalence ratio and a peak flicker exists for a given air flow rate.

Abstract-Two inertial sensor systems were developed for 3D tracking of upper limb movement. One utilizes four sensors and a Kinematic model to track the positions of all four upper limb segments/joints and the other uses one sensor and a Dead Reckoning algorithm to track a single upper limb segment/joint. Initial evaluation indicates that the system using the Kinematic Model is able to track orientation to 1 degree and position to within 0.1 cm over a distance of 10 cm. The dead reckoning system combined with the 'Zero Velocity Update' correction can reduce errors introduced through double integration of errors in the estimate in offsets of the acceleration from several meters to 0.8% of the total movement distance. Preliminary evaluation of the systems has been carried out on ten healthy volunteers and the Kinematic System has also been evaluated on one patient undergoing neurorehabilitation over a period of ten weeks. The initial evaluation of the two systems also shows that they can monitor dynamic information of joint rotation and position and assess rehabilitation process in an objective way, providing additional clinical insight into the rehabilitation process.

This paper presents an experimental investigation, visualization and validation in the three-dimensional (3D) reconstruction of flame temperature and emissivity distributions by using optical tomographic and two-colour pyrometric techniques. A multi-camera digital imaging system comprising eight optical imaging fibres and two RGB charged-couple device (CCD) cameras are used to acquire two-dimensional (2D) images of the flame simultaneously from eight equiangular directions. A combined logical filtered back-projection (LFBP) and simultaneous iterative reconstruction and algebraic reconstruction technique (SART) algorithm is utilized to reconstruct the grey-level intensity of the flame for the two primary colour (red and green) images. The temperature distribution of the flame is then determined from the ratio of the reconstructed grey-level intensities and the emissivity is estimated from the ratio of the grey level of a primary colour image to that of a blackbody source at the same temperature. The temperature measurement of the system was calibrated using a blackbody furnace as a standard temperature source. Experimental work was undertaken to validate the flame temperature obtained by the imaging system against that obtained using high-precision thermocouples. The difference between the two measurements is found no greater than ±9%. Experimental results obtained on a laboratory-scale propane fired combustion test rig demonstrate that the imaging system and applied technical approach perform well in the reconstruction of the 3D temperature and emissivity distributions of the sooty flame.

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