Office of Naval Intelligence

Exploration and localization are two of the capabilities necessary for mobile robots to navigate robustly in unknown environments. A robot needs to explore in order to learn the structure of the world, and a robot needs to know its own location in order to make use of its acquired spatial information. However, a problem arises with the integration of exploration and localization. A robot needs to know its own location in order to add new information to its map, but a robot may also need a map to determine its own location. We have addressed this problem with ARIEL, a mobile robot system that combines frontier-based exploration with continuous localization. ARIEL is capable of exploring and mapping an unknown environment while maintaining an accurate estimate of its position at all times. In this paper, we describe frontier-based exploration and continuous localization, and we explain how ARIEL integrates these techniques. Then we show results from experiments performed in the exploration of a real-world office hallway environ ment. These results demonstrate that maps learned using exploration without localization suffer from substantial dead reckoning errors, while maps learned by ARIEL avoid these errors and can be used for reliable exploration and navigation.

Washington's so-called Maritime Strategy, which sought to apply US naval might against Soviet vulnerabilities on its maritime flanks, came to full fruition during the 1980s. The strategy, which witnessed a major buildup of US naval forces and aggressive exercising in seas proximate to the USSR, also explicitly targeted Moscow”s strategic missile submarines with the aim of pressuring the Kremlin during crises or the early phases of global war. Relying on a variety of interviews and newly declassified documents, the authors assert that the Maritime Strategy represents one of the rare instances in history when intelligence helped lead a nation to completely revise its concept of military operations.

Methods of text compression in Navy messages are not limited to sentence fragments and the omissions of function words such as the copula be. Text compression is also exhibited within "grammatical" sentences and is identified within noun phrases in Navy messages. Mechanisms of text compression include increased frequency of complex noun sequences and also increased usage of nominalizations. Semantic relationships among elements of a complex noun sequence can be used to derive a correct bracketing of syntactic constructions.

An investigation into the applicability and accuracy of Pritchard's approximation for closely packed transducer arrays is undertaken. A new, "modal" Pritchard approximation is developed, based upon normal modes of the acoustic medium, and is tested for arrays of acoustically hard spheres to ascertain its accuracy in determining the mutual acoustic radiation impedance between array elements. For ka approximately 1, it is found that the modal Pritchard approximation works quite well in approximating the mutual radiation impedance of a two-element array, even for relatively close spacing; but for arrays of three or more scatterers in close proximity the approximation may have relatively large errors. The effect of neglecting inter-element scattering is analyzed for the monopole-to-monopole scattering of various configurations of a three-element array and a sixteen-element double line array.

This study demonstrates that the human-operator transfer function approach may be generalized; from a variety of published experimental data, "capability bounds" upon the transfer function parameters are formed. With such ranges defined, these parameters, forming a type of variable structure, can be used as a mapping function to display in the complex plane the boundaries of human adaptive capacity. These boundaries contain a collection of "critical points" which, used in conjunction with the plant Nyquist contour, permit interpretation of system stability characteristics. Experimental verification of the theory is obtained from previously published empirical studies. A man-monitored system configuration also appears to be susceptible to such stability analysis.

Methods of text compression in Navy messages are not limited to sentence fragments and the omissions of function words such as the copula be. Text compression is also exhibited within "grammatical" sentences and is identified within noun phrases in Navy messages. Mechanisms of text compression include increased frequency of complex noun sequences and also increased usage of nominalizations. Semantic relationships among elements of a complex noun sequence can be used to derive a correct bracketing of syntactic constructions.

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This paper conducts an operational analysis of legacy and future mine warfare systems using discrete event simulation. The research focuses on a comparative analysis of the MCM-1 Avenger ship, supported by the MH-53E helicopter, and the Littoral Combat Ship, supported by external unmanned systems, in active, defense mine countermeasures operations. The paper develops architectural representations of the functional activities associated with mine countermeasures operations, as well as architectural representations of past, current, and potential future physical entities involved in minehunting and mine neutralization. Those architectural representations are used as the basis for the development of two distinct discrete event simulation models, one corresponding to legacy (MCM-1 Avenger) operations and another corresponding to future (Littoral Combat Ship) operations. The results of the simulation are analyzed using statistical regression. The regression results indicate that the key performance drivers for both the legacy and future systems show considerable overlap, and also suggest that the legacy assets meet or exceed the performance of future assets in several measures of effectiveness. The simulation model for the future assets is reconsidered to develop recommendations regarding alterations to the future force that enable the future force to exceed the operational performance of the legacy force.

The Association for the Advancement of Artificial Intelligence was pleased to present the 2010 Fall Symposium Series, held Thursday through Saturday, November 11–13, at the Westin Arlington Gateway in Arlington, Virginia. The titles of the eight symposia are as follows: (1) Cognitive and Metacognitive Educational Systems; (2) Commonsense Knowledge; (3) Complex Adaptive Systems: Resilience, Robustness, and Evolvability; (4) Computational Models of Narrative; (5) Dialog with Robots; (6) Manifold Learning and Its Applications; (7) Proactive Assistant Agents; and (8) Quantum Informatics for Cognitive, Social, and Semantic Processes. The highlights of each symposium are presented in this report.

An investigation into the applicability and accuracy of Pritchard’s approximation for closely packed transducer arrays is undertaken. A new, ‘‘modal’’ Pritchard approximation is developed, based upon normal modes of the acoustic medium, and is tested for arrays of acoustically hard spheres to ascertain its accuracy in determining the mutual acoustic radiation impedance between array elements. For ka≊1, it is found that the modal Pritchard approximation works quite well in approximating the mutual radiation impedance of a two-element array, even for relatively close spacing, but for arrays of three or more scatterers in close proximity, the approximation may have relatively large errors. The effect of neglecting interelement scattering is analyzed for the monopole-to-monopole scattering of various configurations of a three-element array and a 16-element double-line array. [Work supported by ONR.]

This paper highlights the approach taken by the Maritime Domain Awareness (MDA) Community of Interest (COI) in establishing an approach to data sharing that seeks to overcome many of the obstacles to sharing both within the federal government and with international and private sector partners. The approach uses the DOD Net Centric Data Strategy employed through Net Centric Enterprise Services (NCES) Service Oriented Architecture (SOA) foundation provided by Defense Information Systems Agency (DISA), but is unique in that the community is made up of more than just Defense agencies. For the first pilot project, the MDA COI demonstrated how four agencies from DOD, the Intelligence Community, Department of Homeland Security (DHS), and Department of Transportation (DOT) could share Automatic Identification System (AIS) data in a common format using shared enterprise service components.

The purpose of Global TRADER (GT) is not only to gather and query supply-chain transactional data for facts but also to analyze that data for hidden knowledge for the purpose of useful and meaningful pattern prediction. The application of advanced analytics provides benefits beyond simple information retrieval from GT, including computer-aided detection of useful patterns and associations. Knowledge discovery, offering a breadth and depth of analysis unattainable by manual processes, involves three components: repository structures, analytical engines, and user tools and reports. For a large and complex domain like supply-chains, there are many stages to developing the most advanced analytic capabilities; however, significant benefits accrue as components are incrementally added. These benefits include detecting emerging patterns; identifying new patterns; fusing data; creating models that can learn and predict behavior; and identifying new features for future tools. The GT Analyst Toolset was designed to overcome a variety of constraints, including lack of third party data, partial data loads, non-cleansed data (non-disambiguation of parties, misspellings, transpositions, etc.), and varying levels of analyst experience and expertise. The end result was a set of analytical tools that are flexible, extensible, tunable, and able to support a wide range of analyst demands.