• The Transactions of the Korea Information Processing Society
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• v.6 no.2
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• pp.274-281
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• 1999

Many popularly used recent high-sped and high-capacity disks use the Zone-Structured in which a disk consists of multiple zones. A zone-structured disk has multiple zones, and the bandwidth and the number of sectors in each zone are different from each other. When the previous studies that modeled disks based on the assumption that the number of sectors in all tracks are same are applied to the zone-structured disk and the video data stored in a round-robin manner are read out with the SCAN technique, the transfer rate of the disk is fixed with that of the innermost zone. And excessive disk space is wasted either. To resolve the problem, this paper proposes a method for reconstructing the physical zones into logical zones by split and merge operations and develops a method for determining optimum transfer block size.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.25 no.9
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• pp.506-515
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• 2013

The PFT (PerFluorocarbon Tracergas Technique) is of advantage to field surveys for evaluating the ventilation condition, due to its simplicity and convenience. On the other hand, it requires researchers to make some additional considerations that include uncertainties, such as the substance concentration distribution in indoor air, representativeness of a sampler, deviation of emission sources, and analysis error. In this study, the PFT and $CO_2$ tracer gas methods were applied simultaneously, to evaluate the accuracy of PFT on six ventilation conditions in the three-storied detached house. The air exchange and the outdoor air introduction a between and into zones were measured. As the results, deviations of PFT concentration distributions were observed at a sufficiently low level for an accurate determination for a house where the interior height was large, and there were relatively many partition walls. However, when a uniform airflow appeared in the indoor air, it was also validated that the indoor air would be exhausted without sufficient mixing, and consequently the measurement error of the PFT would be large.