SCIENTIFIC AND TECHNICAL AEROSPACE REPORTS
A Biweekly Publication of the National Aeronautics and Space Administration
VOLUME 43, ISSUE 26 - DECEMBER 30, 2005
63 CYBERNETICS, ARTIFICIAL INTELLIGENCE AND ROBOTICS
Includes feedback and control theory, information theory, machine learning, and expert systems.
For related information see also 54 Man/System Technology and Life Support.
20050243563Maryland Univ., Baltimore, MD USA
Intelligent Agents Meet Semantic Web in a Smart Meeting Room
Chen, Harry; Perich, Filip; Chakraborty, Dipanjan; Finin, Tim; Joshi, Anupam; Jan. 1, 2005; 9 pp.; In EnglishContract(s)/Grant(s): F30602-97-1-0215; NSF 98-75433Report No.(s): AD-A439732; No Copyright; Avail.: CASI: A02, Hardcopy
We describe a new smart meeting room system called EasyMeeting that explores the use of FIPA agent technologies,Semantic Web ontologies, logic reasoning, and security and privacy policies. Building on a pervasive computing system thatwe have developed previously, Easy Meeting can provide relevant services and information to meeting participants based ontheir situational needs. Our system exploits the context-aware support provided by the Context Broker Architecture (CoBrA).Central to CoBrA is an intelligent broker agent that maintains a shared model of context for all computing entities in the spaceand enforces the privacy policies defined by the users. We also describe the use of CoBrA ontologies, logic reasoning, andprivacy protection mechanisms, and evaluate our initial user experience studies.DTIC
Semantics; Architecture (Computers); Artificial Intelligence
20050244560 Maryland Univ., College Park, MD USA
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The Performance of a Deformable-Membrane Tactile Sensor: Basic Results on Geometrically-Defined Tasks
Hristu, Dimitris; Ferrier, Nicola J.; Brockett, Roger W.; Jan. 1, 1999; 8 pp.; In EnglishContract(s)/Grant(s): DAAG55-97-1-0114; DAAL03-92-G-0115Report No.(s): AD-A439988; CDCSS-TR-99-4; ISR-TR-99-53; No Copyright; Avail.: Defense Technical Information Center(DTIC)
The limitations of rigid fingertips in the precise and algorithmic study of manipulation have been discussed in manyworks, some dating back more than a decade. Despite that fact, much of the work in dexterous manipulation has continuedto use the ‘point-contact’ model for finger-object interactions. In fact, most of the existing tactile sensing technologies are notadaptable to deformable fingertips. The authors present the results of tactile sensing experiments with a new, deformable,gel-filled tactile sensor. Previous work (Shimoga & Goldenberg) has shown the superiority of gel fingertips for forcedissipation and conformability. This sensor reconstructs the shape of an elastic membrane using image data, thus providinga rich set of tactile information. The experiments presented here demonstrated the performance of this sensor in simple tasksinvolving contact localization, spatial resolution, contact depth, and curvature discrimination. For small deformations of themembrane, the contact localization error was less than 0:1mm over a 4 sq cmarea, while the spatial resolution was better than2mm. The sensor can accurately determine deformation depth for small deformations. Curvature estimation is monotonic,however the estimates suffer from the low resolution of the numerical data used to compute derivatives.DTIC
Deformation; Detectors; Fingers; Images; Membranes; Robots; Tactile Sensors (Robotics); Touch
20050244565 Altarum Inst., Ann Arbor, MI USA
Expert Assessment of Human-Human Stigmergy
Parunak, H. V.; Oct. 1, 2005; 38 pp.; In English; Original contains color illustrationsReport No.(s): AD-A440006; DRDC-CR-2005-003; No Copyright; Avail.: Defense Technical Information Center (DTIC)
Human-Human Stigmergy is pervasive. A wide range of pre-computer social systems fit the pattern of stigmergiccoordination, and have provided a rich set of metaphors on which a diverse set of computer-enabled systems for enablinghuman stigmergy have been constructed. It would be more difficult to show a functioning human institution that is notstigmergic, than it is to find examples of human stigmergy. The reason that human-human stigmergy is so common can beunderstood from the growing body of experience in constructing large-scale distributed computing systems with resourceconstrainedelements. It has become clear that central control of such systems is not feasible, since resource-constrainedcomponents cannot cope with the large-scale, distributed aspects of such systems. The central insight of stigmergy is thatcoordination can be achieved by resource-constrained agents interacting locally in an environment. Two fundamentalprinciples govern the success of this strategy: 1. No matter how large the environment grows, because agents interact onlylocally, their limited processing capabilities are not overwhelmed; 2. Through the dynamics of self-organization, localinteractions can yield a coherent system-level outcome that provides the required control.DTIC
Military Technology; Self Organizing Systems
20050244603 Maryland Univ. Baltimore County, Catonsville, MD USA
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Automated System for Text Detection Individual Video Images
Du, Yingzi; Chang, Chein-I; Thouin, Paul D.; Jul. 1, 2003; 14 pp.; In English Contract(s)/Grant(s): MDA-904-00-C2120 Report No.(s): AD-A440110; No Copyright; Avail.: Defense Technical Information Center (DTIC)
Text detection in video images is a challenging research problem because of the poor spatial resolution and complex background, which may contain a variety of colors. An automated system for text detection in video images is presented. It makes use of four modules to implement a series of processes to extract text regions from video images. The first module, called the multistage pulse code modulation (MPCM) module, is used to locate potential text regions in color video images. It converts a video image to a coded image, with each pixel encoded by a priority code ranging from 7 down to 0 in accordance with its priority, and further produces a binary thresholded image, which segments potential text regions from the background. The second module, called the text region detection module, applies a sequence of spatial filters to remove noisy regions and eliminate regions that are unlikely to contain text. The third module, called the text box finding module, merges text regions and produces boxes that are likely to contain text. Finally, the fourth module, called the optical character recognition (OCR) module, eliminates the text boxes that produce no OCR output. An extensive set of experiments is conducted and demonstrates that the proposed system is effective in detecting text in a wide variety of video images. DTIC
Data Processing; Detection; Texts
20050244960 California Univ., Santa Barbara, CA, USA
Designing and Implementing a Family of Intrusion Detection Systems
Kemmerer, Richard A.; Adaptive Defence in Unclassified Networks; November 2004; 55 pp.; In English; RTO IST Symposium on ‘Adaptive Defence in Unclassified Networks’, April 19-20, 2005, Toulouse, France; See also 20050244938; Original contains color illustrations; Copyright; Avail.: CASI: A04, Hardcopy; Available from CASI on CD-ROM only as part of the entire parent document)
Intrusion detection systems (IDSs) analyze information about the activities performed in a computer system or network, looking for evidence of malicious behavior.
Attacks against a system manifest themselves in terms of events. These events can be of a different nature and level of granularity. For example, they may be represented by network packets, operating system calls, audit records produced by the operating system auditing facilities, or log messages produced by applications.
The goal of intrusion detection systems is to analyze one or more event streams and identify manifestations of attacks. The intrusion detection community has developed a number of different tools that perform intrusion detection in particular domains (e.g., hosts or networks), in specific environments (e.g., Windows NT or Solaris), and at different levels of abstraction (e.g., kernel-level tools and alert correlation systems).
These tools suffer from two main limitations: they are developed ad hoc for certain types of domains and/or environments, and they are difficult to configure, extend, and control remotely. In the specific case of signature-based intrusion detection systems the sensors are equipped with a number of attack models that are matched against a stream of incoming events.
The attack models are described using an ad hoc, domain-specific language (e.g., N-code, which is the language used by the Network Flight Recorder intrusion detection system). Therefore, performing intrusion detection in a new environment requires the development of both a new system and a new attack modeling language. As intrusion detection is applied to new and previously unforeseen domains, this approach results in increased development effort.
Today’s networks are not only heterogeneous, but also dynamic. Therefore, intrusion detection systems need to support mechanisms to dynamically change their configuration as the security state of the protected system evolves.
Most existing intrusion detection systems are initialized with a set of signatures at startup time. Updating the signature set requires stopping the IDS, adding new signatures, and then restarting execution. Some of these systems provide a way to enable/disable some of the available signatures, but few systems allow for the dynamic inclusion of new signatures at execution time. In addition, the ad hoc nature of existing IDSs does not allow one to dynamically configure a running sensor so that a new event stream can be used as input for the security analysis. Another limitation of existing IDSs is the relatively static configuration of responses.
Normally it is possible to choose only from a specific subset of possible responses. In addition, to our knowledge, none of the systems allows one to associate a response with intermediate steps of an attack. This is a severe limitation, especially in the case of distributed attacks carried out over a long time span. Finally, the configuration of existing IDSs is mostly performed manually and at a very low level. This task is particularly error-prone, especially if the intrusion detection systems are deployed across a very heterogeneous environment and with very different configurations. This talk describes a framework for the development of intrusion detection systems, called STAT, that overcomes these limitations.
The STAT framework includes a domain-independent attack modeling language and adomain-independent event processing analysis engine. The framework can be extended in a well-defined way to match new domains, new event sources, and new responses. The resulting set of applications is a software family whose members share a number of features, including dynamic reconfigurability and a fine-grained control over a wide range of characteristics. The main advantage of this approach is the limited development effort and the increased reuse that result from using an object-oriented framework and a component-based approach.
STAT is both unique and novel. FirstTAT is the only known framework-based approach to the development of intrusion detection systems. Second, even though the use of frameworks to develop families of systems is a well-known approach, the STAT framework is novel in the fact that the framework extension process includes, as a by-product, the generation of an attack modeling language closely tailored to the target environment. This talk focuses primarily on the STAT framework. Author
Detection; Security; Warning Systems
20050245168 Organisatie voor Toegepast Natuurwetenschappelijk Onderzoek, The Hague, Netherlands
Intelligent Diagnostiek: Reasons with Causal Connections
Gillis, M. P. W.; September 2005; 51 pp.; In English; Original contains color illustrations Contract(s)/Grant(s): TNO Proj. 015.34263 Report No.(s): TD2005-0311; TNO-DVI-2005-A048; Copyright; Avail.: Other Sources
Due to the increasing complexity and integration of modern ship systems, diagnosis of system failures becomes increasingly difficult. To this end, tools must be developed to assist the maintainers of the systems in diagnosis and repair tasks. This report outlines the development and evaluation of an autonomous tool to localize defects based on system messages. The modelling technique is based Bayesian networks. Author
Autonomy; Bayes Theorem; Ships
Source: NASA
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