Survey of Error Concealment techniques: Research directions and open issues

© 2015 IEEE. Error Concealment (EC) techniques use either spatial, temporal or a combination of both types of information to recover the data lost in transmitted video. In this paper, existing EC techniques are reviewed, which are divided into three categories, namely Intra-frame EC, Inter-frame EC, and Hybrid EC techniques. We first focus on the EC techniques developed for the H.264/AVC standard. The advantages and disadvantages of these EC techniques are summarized with respect to the features in H.264. Then, the EC algorithms are also analyzed. These EC algorithms have been recently adopted in the newly introduced H.265/HEVC standard. A performance comparison between the classic EC techniques developed for H.264 and H.265 is performed in terms of the average PSNR. Lastly, open issues in the EC domain are addressed for future research consideration

Resilient Secure Aggregation for Vehicular Networks

Innovative ways to use ad hoc networking between vehicles are an active research topic and numerous proposals have been made for applications that make use of it. Due to the bandwidth-limited wireless communication medium, scalability is one crucial factor for the success of these future protocols. Data aggregation is one solution to accomplish such scalability. The goal of aggregation is to semantically combine information and only disseminate this combined information in larger regions. However, the integrity of aggregated information cannot be easily verified anymore. Thus, attacks are possible resulting in lower user acceptance of applications using aggregation or, even worse, in accidents due to false information crafted by a malicious user. Therefore, it is necessary to design novel mechanisms to protect aggregation techniques. However, high vehicle mobility, as well as tight bandwidth constraints, pose strong requirements on the efficiency of such mechanisms. We present new security mechanisms for semantic data aggregation that are suitable for use in vehicular ad hoc networks. Resilience against both malicious users of the system and wrong information due to faulty sensors are taken into consideration. The presented mechanisms are evaluated with respect to their bandwidth overhead and their effectiveness against possible attacks

Untangling a Web of Lies: Exploring Automated Detection of Deception in Computer-Mediated Communication

Safeguarding organizations against opportunism and severe deception in computer-mediated communication (CMC) presents a major challenge to CIOs and IT managers. New insights into linguistic cues of deception derive from the speech acts innate to CMC. Applying automated text analysis to archival email exchanges in a CMC system as part of a reward program, we assess the ability of word use (micro-level), message development (macro-level), and intertextual exchange cues (meta-level) to detect severe deception by business partners. We empirically assess the predictive ability of our framework using an ordinal multilevel regression model. Results indicate that deceivers minimize the use of referencing and self-deprecation but include more superfluous descriptions and flattery. Deceitful channel partners also over structure their arguments and rapidly mimic the linguistic style of the account manager across dyadic e-mail exchanges. Thanks to its diagnostic value, the proposed framework can support firms’ decision-making and guide compliance monitoring system development

Semantic correlation of behavior for the interoperability of heterogeneous simulations

A desirable goal of military simulation training is to provide large scale or joint exercises to train personnel at higher echelons. To help meet this goal, many of the lower echelon combatants must consist of computer generated forces with some of these echelons composed of units from different simulations. The object of the research described is to correlate the behaviors of entities in different simulations so that they can interoperate with one another to support simulation training. Specific source behaviors can be translated to a form in terms of general behaviors which can then be correlated to any desired specific destination simulation behavior without prior knowledge of the pairing. The correlation, however, does not result in 100% effectiveness because most simulations have different semantics and were designed for different training needs. An ontology of general behaviors and behavior parameters, a database of source behaviors written in terms of these general behaviors with a database of destination behaviors. This comparison is based upon the similarity of sub-behaviors and the behavior parameters. Source behaviors/parameters may be deemed similar based upon their sub-behaviors or sub-parameters and their relationship (more specific or more general) to destination behaviors/parameters. As an additional constraint for correlation, a conversion path from all required destination parameters to a source parameter must be found in order for the behavior to be correlated and thus executed. The length of this conversion path often determines the similarity for behavior parameters, both source and destination. This research has shown, through a set of experiments, that heuristic metrics, in conjunction with a corresponding behavior and parameter ontology, are sufficient for the correlation of heterogeneous simulation behavior. These metrics successfully correlated known pairings provided by experts and provided reasonable correlations for behaviors that have no corresponding destination behavior. For different simulations, these metrics serve as a foundation for more complex methods of behavior correlation

A technique for determining viable military logistics support alternatives

A look at today's US military will see them operating much beyond the scope of protecting and defending the United States. These operations now consist of, but are not limited to humanitarian aid, disaster relief, and conflict resolution. This broad spectrum of operational environments has necessitated a transformation of the individual military services into a hybrid force that can leverage the inherent and emerging capabilities from the strengths of those under the umbrella of the Department of Defense (DOD), this concept has been coined Joint Operations. Supporting Joint Operations requires a new approach to determining a viable military logistics support system. The logistics architecture for these operations has to accommodate scale, time, varied mission objectives, and imperfect information. Compounding the problem is the human in the loop (HITL) decision maker (DM) who is a necessary component for quickly assessing and planning logistics support activities. Past outcomes are not necessarily good indicators of future results, but they can provide a reasonable starting point for planning and prediction of specific needs for future requirements. Adequately forecasting the necessary logistical support structure and commodities needed for any resource intensive environment has progressed well beyond stable demand assumptions to one in which dynamic and nonlinear environments can be captured with some degree of fidelity and accuracy. While these advances are important, a holistic approach that allows exploration of the operational environment or design space does not exist to guide the military logistician in a methodical way to support military forecasting activities. To bridge this capability gap, a method called A Technique for Logistics Architecture Selection (ATLAS) has been developed. This thesis describes and applies the ATLAS method to a notional military scenario that involves the Navy concept of Seabasing and the Marine Corps concept of Distributed Operations applied to a platoon sized element. This work uses modeling and simulation to incorporate expert opinion and knowledge of military operations, dynamic reasoning methods, and certainty analysis to create a decisions support system (DSS) that can be used to provide the DM an enhanced view of the logistics environment and variables that impact specific measures of effectiveness.Ph.D.Committee Chair: Mavris, Dimitri; Committee Member: Fahringer, Philip; Committee Member: Nixon, Janel; Committee Member: Schrage, Daniel; Committee Member: Soban, Danielle; Committee Member: Vachtsevanos, Georg

A Framework for Harmonizing Forensic Science Practices and Digital/Multimedia Evidence

Like many other specializations within forensic science, the digital/multimedia discipline has been challenged with respect to demonstrating that the processes, activities, and techniques used are sufficiently scientific. To address this issue, in April 2015, the Organization of Scientific Area Committees for Forensic Science (OSAC) Digital/Multimedia Scientific Area Committee (SAC) established a Task Group (TG). This document summarizes the work of the TG that grew into establishing a harmonizing framework for forensic science practices and digital/multimedia evidence. The TG researched and deliberated on the essential elements of digital/multimedia science, the nature of evidence examined, the overarching scientific principles and reasoning processes, the questions addressed by core forensic processes, and the activities and techniques which support the core forensic processes. It reviewed a large volume of pertinent literature, conducted interviews of practitioners, academics, and other interested parties. Over a three-year period and many hours of debate, more than 40 discussion drafts were produced. The TG determined that digital/multimedia evidence, and other forensic disciplines, would be in a much stronger position to demonstrate their scientific basis as a harmonized forensic science rather than as mere disciplines at the intersection of forensic specialties and other sciences. The value of forensic science as a whole is that it uses scientific reasoning and processes within the framework articulated in this document to address questions – specific to an event or a case – for legal contexts, to provide decision-makers with trustworthy understanding of the traces in order to help them make decisions. The TG considered how the definitions and framework developed in the context of digital/multimedia evidence mesh with forensic science as a whole. The present document describes the concept of traces as the core nature of forensic evidence and the fundamental object of study in forensic science. It proposes a broad definition of forensic science, not limited to legal problems in civil and criminal justice systems (courtroom contexts), and describes the different types of reasoning that play a significant role in forensic science. Then it defines five core forensic processes, seven forensic activities, and three operational techniques. The formalization of forensic science reasoning processes and outcomes in this work leads to increased reliability, repeatability, and validation in forensic results. This, in turn, gives decision-makers increased confidence in and understanding of forensic results. The resulting definitions and framework can be used to harmonize concepts and practices within digital/multimedia science, and are likely applicable to most forensic disciplines. As such, this work may be useful in articulating their scientific basis, and promoting forensic science as one science, which is more than the union of a patchwork of forensic disciplines. The new paradigm created by the digital realm brings a unique opportunity to revisit fundamental definitions in forensic science and to strengthen the identity of forensic science as a whole, unified by common principles and processes that can address questions for legal contexts. This document represents the conclusions and recommendations of the TG as of the date of its writing. The work continues and future versions of this document can be expected to contain new observations and updated conclusions

Approximate Decoding Approaches for Network Coded Correlated Data

This paper considers a framework where data from correlated sources are transmitted with help of network coding in ad-hoc network topologies. The correlated data are encoded independently at sensors and network coding is employed in the intermediate nodes in order to improve the data delivery performance. In such settings, we focus on the problem of reconstructing the sources at decoder when perfect decoding is not possible due to losses or bandwidth bottlenecks. We first show that the source data similarity can be used at decoder to permit decoding based on a novel and simple approximate decoding scheme. We analyze the influence of the network coding parameters and in particular the size of finite coding fields on the decoding performance. We further determine the optimal field size that maximizes the expected decoding performance as a trade-off between information loss incurred by limiting the resolution of the source data and the error probability in the reconstructed data. Moreover, we show that the performance of the approximate decoding improves when the accuracy of the source model increases even with simple approximate decoding techniques. We provide illustrative examples about the possible of our algorithms that can be deployed in sensor networks and distributed imaging applications. In both cases, the experimental results confirm the validity of our analysis and demonstrate the benefits of our low complexity solution for delivery of correlated data sources

Terrain Representation And Reasoning In Computer Generated Forces : A Survey Of Computer Generated Forces Systems And How They Represent And Reason About Terrain

Report on a survey of computer systems used to produce realistic or intelligent behavior by autonomous entities in simulation systems. In particular, it is concerned with the data structures used by computer generated forces systems to represent terrain and the algorithmic approaches used by those systems to reason about terrain

Mobile Ad-Hoc Networks

Being infrastructure-less and without central administration control, wireless ad-hoc networking is playing a more and more important role in extending the coverage of traditional wireless infrastructure (cellular networks, wireless LAN, etc). This book includes state-of-the-art techniques and solutions for wireless ad-hoc networks. It focuses on the following topics in ad-hoc networks: quality-of-service and video communication, routing protocol and cross-layer design. A few interesting problems about security and delay-tolerant networks are also discussed. This book is targeted to provide network engineers and researchers with design guidelines for large scale wireless ad hoc networks