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v-Anomica: A Fast Support Vector-Based Novelty Detection Technique

Ames Research Center, Moffett Field, California Outlier or anomaly detection refers to the task of identifying abnormal or inconsistent patterns from a dataset. While they may seem to be undesirable entities, identifying them has many potential applications in fraud and intrusion detection, medical research, and safety-critical vehicle health management. Outliers can be detected using supervised, semi-supervised, or unsupervised techniques. Unsupervised techniques do not require labeled instances for detecting outliers. Supervised techniques require labeled instances of both normal and abnormal operation data for first building a model (e.g., a classifier), and then testing if an unknown data point is a normal one or an outlier. The model can be probabilistic such as Bayesian inference or deterministic such as decision trees, Support Vector Machines (SVMs), and neural networks. Semi-supervised techniques only require labeled instances of normal data. Hence, they are more widely applicable than the fully supervised ones. These techniques build models of normal data and then flag outliers that do not fit the model.

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Self-Stabilizing Distributed Clock Synch ronization Protocol for Arbitrary Digraphs

Langley Research Center, Hampton, Virginia A report describes a self-stabilizing distributed clock synchronization protocol in the absence of faults in the system. It is focused on the distributed clock synchronization of an arbitrary, non-partitioned digraph ranging from fully connected to 1-connected networks of nodes, while allowing for differences in the network elements. The protocol does not rely on assumptions about the initial state of the system, other than the presence of at least one node, and no central clock or a centrally generated signal, pulse, or message is used.

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Precision Navigation Strategies for Primitive Solar-System-Body Sample Return Missions

Goddard Space Flight Center, Greenbelt, Maryland This project investigated advanced navigation strategies required to approach, perform proximity operations, and return a sample from an asteroid or comet. An optimized navigation strategy for a notional mission to a near-Earth asteroid was developed to serve as a baseline for future missions and mission proposals. Essential simulation and analysis software enhancements were developed and implemented in the Orbit De ter mination Toolbox (ODTBX), an open-source, early mission navigation analysis tool suite built on a flexible architecture. The development efforts of this project resulted in the first fully open-source tool suite with the capabilities of performing primitive body navigation simulation and analyses.

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Orbit Determination Toolbox 2012a (v5.0)

Goddard Space Flight Center, Greenbelt, Maryland The Orbit Determination Toolbox (ODTBX) 2012a (v5.0) is an advanced mission simulation and analysis tool used for concept exploration, proposal, early design phase, or rapid design center environments: the emphasis is on flexibility, but it has enough fidelity to produce credible results. ODTBX v5.0 includes multiple feature additions, enhancements, and bug fixes from the prior release (v4.5). The primary user interface and supporting functions are written in Matlab and Java.

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Design and Construction of Protograph-Based LDPC Codes

This innovation can be used in magnetic tape recording and other channels with finite-state representation. NASA’s Jet Propulsion Laboratory, Pasadena, California Writing (recording) to a storage device and reading from it can be considered as a noisy channel. A storage device such as magnetic recoding and optical recording can be modeled as a partial response channel. Partial-response techniques are a special case of precoding technique where the intersymbol interference is forced to some known pattern. Thus, read-back data from storage devices may have intersymbol interference.

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Spitzer Integrated Resource Planning and Scheduling System (SIRPASS)

NASA’s Jet Propulsion Laboratory, Pasadena, California This decision support system provides an integrated platform for assessing the quality of Spitzer scheduling options. The application aids in scheduling instrument selection, assigns schedule times to specific observation requests, and generates stored sequence products destined for execution on the Spitzer Space Telescope.

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Tracking a Scene on Earth from Space Using the Adaptive Cross-Correlation Algorithm

NASA’s Jet Propulsion Laboratory, Pasadena, California A software program enables a user to track a scene or a spot on Earth from space (such as from the ISS) using an innovative algorithm. This robust and highly accurate software allows a scene to be tracked that can be not only the shifted version of a previous scene, but can also be a distorted one.

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