Ahmed Elmagarmid

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ii ACKNOWLEDGMENTS First of all I would like to thank my advisor, Rich DeMillo, who gave me the initial impetus to look into the problem of software debugging and helped me develop many ideas presented in this dissertation. I am also grateful to my co-advisor, Gene Spaord, whose expert advise, particularly on implementation issues, was always indispensable.(More)
ii To my family iii ACKNOWLEDGMENTS I would rst like to thank my advisor, Rich DeMillo, for his patience, guidance, and friendship throughout my graduate career. A special thanks goes to Aditya Mathur, whose encouragement, wisdom, and advice have sustained my progress, especially during the past two years. To Gene Spaord goes my gratitude for a(More)
UNLABELLED Healthcare can be enhanced by the effective use of information technology to improve the quality and safety of care and many healthcare providers are adopting advanced health information technology to improve their healthcare delivery process. Qatar is a relatively young Middle Eastern country with an ambitious and progressive national strategy(More)
The concept of Negative Tuples (or delete tuples) has been adopted widely in data stream management systems to evaluate continuous sliding-window queries incrementally. The main idea is to produce a negative tuple for each expired tuple from the sliding window. Thus, various query operators can update their state based on the expired tuples. Negative tuples(More)
BACKGROUND The importance of sleep is paramount to health. Insufficient sleep can reduce physical, emotional, and mental well-being and can lead to a multitude of health complications among people with chronic conditions. Physical activity and sleep are highly interrelated health behaviors. Our physical activity during the day (ie, awake time) influences(More)
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