M.S. - Information and Computer Sciences

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    The Cipher Mail Transport Protocol (CMTP)
    ([Honolulu] : [University of Hawaii at Manoa], [August 2016], 2016-08) Moroney, Jonathan
    The Cipher Mail Transport Protocol (CMTP) is a new mail transport system designed to make encryption the default option for email. This thesis lays out what a modern email system is, how it works, the shortcomings of the current system and will propose CMTP as a solution. CMTP provides a solution to these problems in an effort to secure email transmission and storage. In- spired by the Pretty Good Privacy (PGP) email security system, CMTP implements public key cryptography, hidden from users, while maintaining the broad usability of email. This is in contrast to secure protocols that pre-date CMTP and generally provide good security, but reduce usability. After an initial, unauthenticated key exchange, CMTP encrypts and authenticates all messages. In this way, CMTP provides security without compromising usability.
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    Automated cinematography and editing for 3D computer graphics scenes
    ([Honolulu] : [University of Hawaii at Manoa], [December 2010], 2010-12) Kardan, Kaveh
    We present an approach to generate cinematic sequences from event-based descriptions of 3D computer graphics scenes of conversations between groups of actors. We break the problem into two parts: cinematography and editing. Our cinematography approach creates camera setups using a combination of geometric constraints and aesthetic parameters, while ensuring that the resulting cinematic sequence obeys the heuristics of traditional cinematography. More specifically, our main contributions are a method for defining hierarchical lines of action and the identification and use of relevant first principles of cinematography for using these lines of actions. Our approach is more flexible and powerful than those proposed in previous work, mainly because it naturally generalizes to any number of actors in a scene. On the editing side, we present a set of heuristics for editing shots into a coherent movie clip which obeys the conventions of continuity editing. Our approach mimics the decision processes of an editor assembling a clip out of filmed footage involving multiple camera setups. Given a set of stylistic rules, our software applies a number of heuristics to produce a final result satisfying those rules, as well as the fundamental rules of continuity editing. The main contribution of this work is in the formulation of editing heuristics which take into account stylistic rules, enabling different edits of the same scene into cinematic clips of various styles. We demonstrate the use of these heuristics on three scenes taken from actual film clips.
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    The Lusus Protocol
    ( 2005-08) Morton, Daniel H.
    Wireless sensor networks are groups of nodes which sample data from one or more attached sensors and cooperate via wireless links to transmit this data to a destination. This document introduces Lusus, a new protocol designed to operate wireless sensor networks for ecological monitoring. Unlike other protocols with a more general design focus, Lusus assumes that the vast majority of information travels towards a central point. This allows Lusus to use specific routes in an efficient manner since the only route a node need know is the next hop towards the center of the network. Lusus uses a limited form of route discovery transmitted periodically from the center of the network and relayed by each node in the network. This periodic route discovery flood is done on the order of hours to save bandwidth. The routing overhead in Lusus is significantly less than in other protocols. Lusus assumes that data items are small (several bytes) in size. Furthermore Lusus is designed to optimize transferring small units of data. Individual pieces of data in a Lusus network are packaged within self-contained units. Because of this, nodes are allowed to combine the data from multiple separate packets into a single outgoing packet. This allows Lusus networks to save on overhead and thus increase their efficiency. This combining of data results in an overhead of 27% per piece of data whereas without combining the overhead is 85%. To help ensure data reception, Lusus uses hop-by-hop acknowledgments. This type of acknowledgment is necessary to support the data combining feature of Lusus. This document describes the operation of Lusus and offers an analysis of its performance for large and for dense networks.
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