The on-going data revolution demands storage systems that can store very large quantities of data while being fast, reliable and cheap. Emerging storage technologies such as flash and granular media offer improved densities, faster access times, and are more power-efficient than conventional hard disk drives. The primary drawback associated with these new devices is their high error rate, caused by difficulties in programming, voltage drift, and wear-out. Coding methods used in existing storage applications are based on symmetric, Hamming-type metrics. However, when used in new memory devices, these traditional approaches result in costly overprovisioning. In this work, we present advanced coding-theoretic techniques applicable to modern storage devices that exploit the asymmetries in the underlying physical operations for improved performance. In many cases of interest, the results in this thesis represent the state of the art. Taken collectively, our results can help enable all modern, data-intensive technologies that require reliably storing large quantities of data.

As the number of units in underwater sensor arrays grow, low-cost localization becomes increasingly important to maintain network scalability. Methods using ambient ocean noise are promising solutions because they do not require external infrastructure, nor expensive on-board sensors. Here we extend past work in stationary array element localization from correlations of ambient noise to a mobile sensor array. After obtaining inter-node distance estimates using ambient noise correlations, these distances can be used to determine a relative localization of an array of mobile underwater sensor platforms without introducing any external infrastructure or on-board localization sensors.

In this work we explore the effects of receiver mobility on inter-node distance estimation via correlations of ambient acoustic noise. Through analysis and simulation, we develop an exact solution along with a more tractable approximation to the peak amplitude of the time-domain Green's function between the two mobile receivers, which provides an estimate of their spatial separation. Here we demonstrate that the mobile noise correlation amplitude at the average time delay between the receivers can be modeled with the wideband ambiguity function of a single sound source. We then use this approximation to discuss selection of design parameters and their effects on the noise correlation function.

This work acts as a piece in the larger problem of infrastructure-free localization for mobile underwater sensor networks. Combining a relative localization from this method with the absolute positions of several units could provide an absolute localization of an entire array, without the need for external infrastructure.

The fifteenth-century Buddhist monk and paṇḍita Vanaratna lived a remarkable life that unfolded across the length and breadth of South Asia and crossed the Himalayan range. As a teacher, author, and pilgrim, Vanaratna traveled through and lived among many of the diverse Buddhist communities of his time and witnessed a tumultuous yet vibrant period in the regions’ history. Vanaratna’s life is particularly compelling for the fact that he counts among the last of the Buddhist paṇḍitas of Indic descent to leave an impression in the historical record. Active in eastern India, Sri Lanka, southern and northern India, Nepal, and Tibet, Vanaratna’s life is accessible to us through a rich and extensive body of Sanskrit and Tibetan literature, as well as art-historical and material sources. This study is not the first to give Vanaratna the attention he merits, but it does aim to be the first to take into consideration this large body of material available on his life that has previously been underutilized or not considered at all. The primary witnesses for Vanaratna’s life examined closely here include the Tibetan biographies (rnam thar) of Vanaratna composed by his immediate disciples, the Tibetan biographies of his students and colleagues, his extant works preserved in Sanskrit and Tibetan translation, and art-historical materials that record his life and deeds. These materials will be coordinated with the broader historical record in order to remedy both the dearth of comprehensive studies of Vanaratna’s life and the scarcity of primary sources on the political and religious history of fifteenth-century South Asia, Nepal, and Tibet.