• Journal of Korea Multimedia Society
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• v.10 no.5
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• pp.583-593
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• 2007

We study the page replacement algorithms for demand paging, called CFLRU/C, CFLRU/E and DL-CFLRU/E, that reduce the number of erase operations and improve the wear-leveling degree of flash memory. Under the CFLRU/C and CFLRU/E algorithms, the victim page is the least recently used dean page within the pre-specified window. However, when there is not any dean page within the window, the CFLRU/C evicts the dirty page with the lowest frequency while the CFLRU/E evicts the dirty page with the highest number of erase operations. The DL-CFLRU/E algorithm maintains two page lists called the dean page list and the dirty page list, and first finds the page within the dean page list when it selects a victim. However, when it can not find any dean page within the dean page list, it evicts the dirty page with the highest number of erase operations within the window of the dirty page list. In this thesis, we show through simulation that the proposed schemes reduce the number of erase operations and improve the wear-leveling than the existing schemes like LRU.

• Journal of radiological science and technology
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• v.43 no.1
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• pp.1-7
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• 2020

In this study, the contamination level was measured using an ATP meter using adenosine triphosphate bioluminescent material to find effective infection control to compensate for the disadvantages of the microbial culture method used for hygiene control of ultrasound probe. The convex probes were selected from six ultrasound probe in the hospital, and the samples were taken in real time before and after cleaning to check the contamination of the probe. In order to classify the pollution degree using the APT meter was classified by category. A total of 78 samples were collected from the ultrasound probe. When the pollution levels before and after cleaning were classified by category, 76.6% of the samples were classified into category 3·4 before cleaning, but they decreased to 23.3% after cleaning. 13.3% before cleaning was in category 1, but increased to 43.3% after cleaning. By classifying the pollution level, it was confirmed that the pollution level was significantly reduced by category. Until now, there was no suitable criterion for determining the contamination level by using ATP meter in medical machines where sample area is small and reused. In this study, criteria for each category were set to measure the contamination level of ATP meter suitable for small sample area such as ultrasound probe, so that contamination level could be determined in real time at the site. Therefore, it is considered that hygiene management for ultrasound probe can be more actively performed.