Yeongju Lee

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As the storage requirements of a video server increase, disks of different types are often added. This makes it essential to manage the energy requirements of heterogeneous disk arrays. We examine how seek operations affect disk energy consumption, and then analyze the relationship between the amount of prefetched data and the number of seeks, and the(More)
We propose adaptive power control of obstacle avoidance system for visually impaired person. It utilizes multiple ultrasonic sensors to avoid obstacles lying in the path. We evaluate complex structure in front of the user with predefined patterns and determine avoidance direction by analysing those patterns. It controls the number of active ultrasonic(More)
Maintenance and upgrades to the significant storage infrastructure in a video server often create a heterogenous disk array. We show how to manage the energy consumption of such an array by combining caching and prefetching techniques. We first examine how seek operations affect disk energy consumption, and then analyze the relationship between the amount(More)
We develop a scheme to analyze problem behaviors of children with developmental disabilities by making use of 3-axis accelerometer, gyroscope, and microphone sensors in a smartwatch. It consists of four phases: classification of behaviors, feature collection, classifier construction and behavior recognition. Real measurements show that the recognition(More)
Skp2 is frequently overexpressed in many human cancers and plays a key role in tumorigenesis. As a component of the SCFSkp2ubiquitin E3 ligase complex, Skp2 is responsible for recruiting substrate proteins for their ubiquitination and subsequent degradation by the 26S proteasome. Thus, Skp2 promotes the cell cycle by down-regulating cell cycle proteins such(More)
Video files contain large amount of data, which can be stored cost-effectively on a hard disk drive, but this consumes a significant energy when it is spinning and ready to read data. The energy used by a disk can be reduced by prefetching video frames into buffer to allow the disk to spin down. But frequent spindowns compromise disk life, so it is(More)