crashes based on program semantics reconstructed from memory dumps. RETracer was designed to meet the requirements of large-scale crash reporting services. RETracer performs binarylevel backward taint analysis without a recorded execution trace to understand how functions on the stack contribute

-world network traffic is largely legitimate and that telltales manifested by exploits rarely appear in network streams lead us to the proposal of Fingerprinter. This framework integrates fingerprinting and PM methods to rapidly distinguish well-behaved from malicious traffic. Fingerprinter produces concise

Flash-based solid-state drives have revolutionized stor-age with their high performance. Their sophisticated in-ternal mechanisms have led to a plethora of research on how to optimize applications, file systems, and internal SSD designs. Due to the closed nature of commercial de-vices though, most research on the internals of an SSD, such as enhanced flash-translation layers, is performed using simulation or emulation. Without implementation in real devices, it can be difficult to judge the true benefit of the proposed designs. In this paper, we describe our efforts to implement two new SSD designs that change both the internal workings of the device and its interface to the host operating sys-tem. Using the OpenSSD Jasmine board, we develop a prototype of FlashTier’s Solid State Cache (SSC) and of the Nameless Write SSD. While the flash-translation layer changes were straightforward, we discovered un-expected complexities in implementing extensions to the storage interface. We describe our implementation process and extract a set of lessons applicable to other SSD prototypes. With our prototype we validate the performance claims of FlashTier and show a 45-52 % performance improvement over caching with an SSD and a 90 % reduction in erases. 1

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ii iv vTo my parents vi vii Acknowledgements I would first and foremost extend my whole-hearted gratitude to my advisors, An-drea Arpaci-Dusseau and Remzi Arpaci-Dusseau. Andrea and Remzi are the reason that I had the opportunity for this exceptional Ph.D. journey. To this day, I still re-member the moment when they took me as their student and the joy and hope in my heart. Andrea and Remzi have showed me what systems research is like and how much fun and challenging it can be. Before this journey with them, I had always liked and believed in the beauty of mathematics and theory. My initial interest in systems research happened when I took Remzi’s Advanced Operating Systems

[ A review of past and recent strategies for sub-Nyquist sampling] Signal processing methods have changed substantially over the last several decades. In modern applications, an increasing number of functions is being pushed forward to sophisticated software algorithms, leaving only delicate finely-tuned tasks for the circuit level. Sampling theory, the gate to the digital world, is the key enabling this revolution, encompassing all aspects related to the conversion of continuous-time signals to discrete streams of numbers. The famous Shannon-Nyquist theorem has become a landmark: a mathematical statement which has had one of the most profound impacts on industrial development of digital signal processing (DSP) systems. Over the years, theory and practice in the field of sampling have developed in parallel routes. Contributions by many research groups suggest a multitude of methods, other than uniform sampling, to acquire analog signals [1]–[6]. The math has deepened, leading to abstract signal spaces and innovative sampling techniques. Within generalized sampling theory, bandlimited signals have no special preference, other than historic. At the same time, the market adhered to the Nyquist paradigm; state-of-the-art analog to digital conversion (ADC) devices provide values of their input at equalispaced time points [7], [8]. The footprints of Shannon-Nyquist are evident

An approach based on Extreme Value Theory as a measure to quantify market risk of equity securities and portfolios