Victor A. Skormin

SVD-Based Approach to Transparent Embedding Data into Digital Images

A new approach to transparent embedding of data into digital images is proposed. It provides a high rate of the embedded data and is robust to common and some intentional distortions. The developed technique employs properties of the singular value decomposition (SVD) of a digital image. According to these properties each singular value (SV) specifies the luminance of the SVD image layer, whereas the respective pair of singular vectors specifies image geometry. Therefore slight variations of SVs cannot affect the visual perception of the cover image. The proposed approach is based on embedding a bit of data through slight modifications of SVs of a small block of the segmented covers. The approach is robust because it supposes to embed extra data into low bands of covers in a distributed way. The size of small blocks is used as an attribute to achieve a tradeoff between the embedded data rate and robustness. An advantage of the approach is that it is blind. Simulation has proved its robustness to JPEG up to 40%. The approach can be used both for hidden communication and watermarking.

Information Assurance in Computer Networks

The paper describes the design of a genetic classifier-based intrusion detection system, which can provide active detection and automated responses during intrusions. It is designed to be a sense and response system that can monitor various activities on the network (i.e. looks for changes such as malfunctions, faults, abnormalities, misuse, deviations, intrusions, etc.). In particular, it simultaneously monitors networked computer’s activities at different levels (such as user level, system level, process level and packet level) and use a genetic classifier system in order to determine a specific action in case of any security violation. The objective is to find correlation among the deviated values (from normal) of monitored parameters to determine the type of intrusion and to generate an action accordingly. We performed some experiments to evolve set of decision rules based on the significance of monitored parameters in Unix environment, and tested for validation.

Data mining technology for failure prognostic of avionics

Adverse environmental conditions have combined cumulative effects leading to performance degradation and failures of avionics. Classical reliability addresses statistically-generic devices and is less suitable for the situations when failures are not traced to manufacturing but rather to unique operational conditions of particular hardware units. An approach aimed at the accurate assessment of the probability of failure of any avionics unit utilizing the known history-of-abuse from environmental and operational factors is presented herein. The suggested prognostic model utilizes information downloaded from dedicated monitoring systems of flight-critical hardware and stored in a database. Such a database can be established from the laboratory testing of hardware and supplemented with real operational data. This approach results in a novel knowledge discovery from data technology that can be efficiently used in a wide area of applications and provide a quantitative basis for the modern maintenance concept known as service-when-needed. An illustrative numerical example is provided.

Autonomous Intelligent Systems: Agents and Data Mining

This volume contains the papers presented at the International Workshop Autonomous Intelligent Systems: Agents and Data Mining (AIS-ADM 2005) held in St. Petersburg, Russia, during June 6 8, 2005. The workshop was - ganized by the St. Petersburg Institute for Informatics and Automation of the Russian Academy of Sciences (SPIIRAS) in cooperation with Binghamton U- versity (SUNY, USA) and the Web Intelligence Consortium. Autonomous Intelligent Systems (AIS) constitute an emerging class of int- ligent information systems integrating recent advances in various technologies of Arti?cial Intelligence. Modern AIS incorporate multi-agent and data mining systemsprovidinganewdimensionforfurtherprogressinintelligentinformation technology. AIS-ADM 2005 provided an international forum to multi-agent and data mining researchers. A total of 29 papers from 15 countries relating to various aspects of both theory and applications of multi-agent systems, data mining and their joint area were submitted to AIS-ADM 2005. Out of them 17 were selected as regular presentations. Three technical sessions were organized, namely: In- gration of Multi-agent and Data Mining Techniques; Ontology Issues and Web Mining; and Applications and Case Studies of the Integrated Technology. The panel discussion was devoted to the mutual enrichment and challenging pr- lems emerging in the joint area of research. The AIS-ADM 2005 program was enriched by six distinguished invited speakers: Nick Jennings, Chengqi Zhang, Mircea Negoita, Pericles Mitkas, Hai Zhuge and Leonid Perlovsky

Adaptive jitter rejection technique applicable to airborne laser communication systems

Satellite jitter adversely affects the pointing, acquisition, and tracking (PAT) functions of an intersatellite laser communication system. Reliable aircraft-based testing of PAT systems requires that the detrimental effects of aircraft jitter be controlled and a realistic satellite jitter environment be emulated. A novel jitter rejection technique, the self-tuning feed-forward compensation scheme, is developed to minimize the effects of aircraft vibration on the PAT terminal. The self-tuning results in the implicit characterization of the mechanical jitter propagation path, thus facilitating the injection of prerecorded satellite jitter in the control circuitry of steering mirrors.

On-line diagnostics of a self-contained flight actuator

A mathematical model describing the dynamics of a self-contained flight control actuator is established. Typical failures of the actuator are defined in the space of the model parameters in the form of a failure pattern library. A diagnostic model of the actuator, intentionally sensitive to particular failures, is defined. A diagnostic procedure, featuring on-line parameter estimation of the diagnostic model, failure detection, and isolation, is proposed. A failure prediction procedure, utilizing trends exhibited by parameter estimates, is formulated. The results are verified by computer simulation. >

Agent-Based Model of Computer Network Security System: A Case Study

The paper considers a multi-agent model of a computer networks security system, which is composed of particular autonomous knowledge-based agents, distributed over the hosts of the computer network to be protected and cooperating to make integrated consistent decisions. The paper is focused on an architecture, implementation and simulation of a case study aiming at exploration distinctions and potential advantages of using such an architecture for the computer network protection. The paper describes the conceptual model and architecture of the particular specialized agents and the system on a whole as well as implementation technology. Simulation scenario, input traffic model and peculiarities of the distributed security system operation are described. The major attention is paid to the intrusion detection task and agents interactions during detection of an attack against the computer network. The advantages of the proposed model of a computer networks security system are discussed.

Modeling of an acousto-optic laser beam steering system intended for satellite communication

High data rate of laser communication systems should be matched by wide operational bandwidth of beam positioning. This could be achieved by the application of nonmechanical beam steering technologies utilizing acousto-optic phenomena. Major components of acousto-optic beam steering systems, a Bragg cell, and a quadrant detector are subjected to comprehensive laboratory testing and characterization as components of a control system. A mathematical and computer simulation model of the entire steering system addressing system dynamics, cross coupling of azimuth and elevation channels, and nonlinearity, and facilitating synthesis of advanced control laws is developed.

On-line diagnostics of a variable displacement pump of a flight actuation system

An on-line diagnostic system for a variable displacement pump, serving as a part of a self-contained flight actuator, is presented. A mathematical model describing dynamics of the pump, driving a control surface of an aircraft, is established. Typical pump failures are defined through the model parameters in the form of a failure pattern library. A diagnostic model, intentionally sensitive to particular failures, is defined. A diagnostic procedure, featuring on-line parameter estimation of the mathematical model, failure detection and identification is developed. A failure prediction procedure, detecting and utilizing trends exhibited by parameter estimates is formulated. The results are verified by computer simulation.

Jitter rejection technique in a satellite-based laser communication system

A technique, resulting in the significant reduction of negative effects of satellite jitter on the accuracy of laser beam positioning in satellite communication systems, is presented. It implies application of vibration monitoring instrumentation for estimation of the motion components constituting jitter. A self-tuning feedforward jitter compensation scheme is introduced to the existing mirror-positioning control systems. The technique is verified by computer simulation and is in the process of experimental investigation.