• Journal of Energy Engineering
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• v.17 no.4
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• pp.189-197
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• 2008

In this study, a system to measure continuously the fuel concentration in a steady flow rig on the basis of Rayleigh scattering is presented. The system can be employed to measure both the temporal and the spatial distribution. Also, it is possible to calibrate the system for the measurement of accurate absolute concentration. Firstly, the system was tested at a calibration chamber for the determination of scattering cross section from propane, butane, acetylene, Freon-12 and Genetron 143a. After this, the system was adapted to a steady flow rig to measure the temporal and spatial fuel concentration. The rig is composed of cylinder head, intake manifold, injector, and transparent cylinder which can simulate internal combustion engine. To cope with the interference of Mie scattering, which is main obstacle of the measuring concentration with Rayleigh scattering, a hardware filter was installed for reducing the number density of particles. Furthermore a software filter was developed, which is based on the rise time and the time constant of the photomultiplier-amplifier system. In addition, background noisy was reduced by adjusting the optical array and applying the pin hall and beam trap. The results show that LRS can provide useful information about concentration field and the software filter is very effective method to remove Mie interference.

• Progress in Medical Physics
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• v.17 no.4
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• pp.238-245
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• 2006

To assess the ability of an extravasation defection accessory (EDA) to detect the clinically important extravascular Injection of iodinated contrast material that was delivered with an automated mechanical power injector. The purpose of this study was to assess the ability of this device during clinically important episodes of extravasation. The EDA system was composed of a strain gage, an amplifier and a computer-based system. In the rabbit experimental cases, there were seven true-positive cases (range of the extravasation volumes: $14{\sim}23 ml$). The algorithm results showed seven true-positive cases (range of the extravasation volumes: $7{\sim}16ml$), nineteen true-negative cases, two false-positive cases and no false-negative cases. The EDA system had a sensitivity of 100% and a specificity of 90% for the detection of clinically important extravasation. The EDA system had good sensitivity for the detection of clinically important extravasation and the EDA system has the clinical potential for the early detection of extravasation of the contrast medium that is administered with power injectors.