Fusing uncertain knowledge and evidence for maritime situational awareness via Markov Logic Networks

The concepts of event and anomaly are important building blocks for developing a situational picture of the observed environment. We here relate these concepts to the JDL fusion model and demonstrate the power of Markov Logic Networks (MLNs) for encoding uncertain knowledge and compute inferences according to observed evidence. MLNs combine the expressive power of first-order logic and the probabilistic uncertainty management of Markov networks. Within this framework, different types of knowledge (e.g. a priori, contextual) with associated uncertainty can be fused together for situation assessment by expressing unobservable complex events as a logical combination of simpler evidences. We also develop a mechanism to evaluate the level of completion of complex events and show how, along with event probability, it could provide additional useful information to the operator. Examples are demonstrated on two maritime scenarios of rules for event and anomaly detection

Context-based Information Fusion: A survey and discussion

This survey aims to provide a comprehensive status of recent and current research on context-based Information Fusion (IF) systems, tracing back the roots of the original thinking behind the development of the concept of \u201ccontext\u201d. It shows how its fortune in the distributed computing world eventually permeated in the world of IF, discussing the current strategies and techniques, and hinting possible future trends. IF processes can represent context at different levels (structural and physical constraints of the scenario, a priori known operational rules between entities and environment, dynamic relationships modelled to interpret the system output, etc.). In addition to the survey, several novel context exploitation dynamics and architectural aspects peculiar to the fusion domain are presented and discussed

Multi-level fusion of hard and soft information

Proceedings of: 17th International Conference on Information Fusion (FUSION 2014): Salamanca, Spain 7-10 July 2014.Driven by the underlying need for a yet to be developed framework for fusing heterogeneous data and information at different semantic levels coming from both sensory and human sources, we present some results of the research being conducted within the NATO Research Task Group IST-106/RTG-051 on "Information Filtering and Multi Source Information Fusion". As part of this on-going effort, we discuss here a first outcome of our investigation on multi-level fusion. It deals with removing the first hurdle between data/information sources and processes being at different levels: representation. Our contention here is that a common representation and description framework is the premise for enabling processing overarching different semantic levels. To this end we discuss here the use of the Battle Management Language (BML) as a way ("lingua franca") to encode sensory data, a priori and contextual knowledge, both as hard and soft data.Publicad

Overview of contextual tracking approaches in information fusion

Proceedings of: Geospatial InfoFusion III. 2-3 May 2013 Baltimore, Maryland, United States.Many information fusion solutions work well in the intended scenarios; but the applications, supporting data, and capabilities change over varying contexts. One example is weather data for electro-optical target trackers of which standards have evolved over decades. The operating conditions of: technology changes, sensor/target variations, and the contextual environment can inhibit performance if not included in the initial systems design. In this paper, we seek to define and categorize different types of contextual information. We describe five contextual information categories that support target tracking: (1) domain knowledge from a user to aid the information fusion process through selection, cueing, and analysis, (2) environment-to-hardware processing for sensor management, (3) known distribution of entities for situation/threat assessment, (4) historical traffic behavior for situation awareness patterns of life (POL), and (5) road information for target tracking and identification. Appropriate characterization and representation of contextual information is needed for future high-level information fusion systems design to take advantage of the large data content available for a priori knowledge target tracking algorithm construction, implementation, and application.Publicad

Sensor Fusion for Video Surveillance

In this paper, a multisensor data fusion system for object tracking is presented. It is able to track in real-time multiple targets in outdoor environments. The system can take advantage of the redundant information coming from different sensors monitoring the same scene. The measurements (positions of the targets) obtained from the available sources are fused together to obtain a more accurate estimate. Data fusion is performed considering sensor reliability at every time instant. A confidence measure has been employed to weight sensor data in the fusion process. Compared to single camera systems, the adopted approach has produced more accurate and continuous trajectories, reducing calibration and segmentation errors

Context-based Information Fusion: A survey and discussion

This survey aims to provide a comprehensive status of recent and current research on context-based Information Fusion (IF) systems, tracing back the roots of the original thinking behind the development of the concept of "context". It shows how its fortune in the distributed computing world eventually permeated in the world of IF, discussing the current strategies and techniques, and hinting possible future trends. IF processes can represent context at different levels (structural and physical constraints of the scenario, a priori known operational rules between entities and environment, dynamic relationships modelled to interpret the system output, etc.). In addition to the survey, several novel context exploitation dynamics and architectural aspects peculiar to the fusion domain are presented and discussed.This work was partially supported by ONRG Grant N62909-14-1-N061, by Projects MINECO TEC2012-37832-C02-01 and CICYT TEC2011-28626-C02-02, and by Mobility Grants Program of Fundación Caja Madrid 2011.Publicad

Network methods and plan recognition for fusion in crisis management

Building and updating a situational picture of the scenario under consideration is the goal of the Situation Assessment (SA) Information Fusion (IF) process. The scenario generally involves multiple entities and actors where possibly only a few under direct control of the decision maker. SA aims at explaining the observed events (mainly) by establishing the entities and actors involved, inferring their goals, understanding the relations existing (whether permanently or temporarily) between them, the surrounding environment, and past and present events. It is therefore apparent how the SA process inherently hinges on understanding and reasoning about relations. SA is a necessary preparatory step to the following phase of Impact Assessment (IA) where the decision maker is interested in estimating the evolution of the situation and the possible outcomes, dangers and threats. SA and IA processes are particularly complex and critical for large-scale scenarios with nearly chaotic dynamics such as those affected by natural or man-made disasters. This chapter will discuss recent developments in information fusion methods for representing and reasoning about relational information and knowledge for event detection in the context of crisis management. In particular, network methods will be analysed as a means for representing and reasoning about relational knowledge with the purpose of detecting complex events or discovering the causes of observed evidence

Levels?

This paper challenges the familiar hierarchical partitioning of data fusion problems into 'levels'. The JDL data fusion model and its variants are seen as a method to partition a problem space in a way that tends to support different types of solutions. The layered view of fusion presented in these models is a rough engineering-based representation of a domain that has been addressed in analytically- and empirically-based models developed over centuries by philosophers and cognitive scientists. These ontological and cognitive models involve distinctions that are not all necessarily hierarchical or sequential. A hierarchical partitioning - while often convenient in characterizing fusion problems - should not be an impediment to fusion solutions that span the levels. A more flexible and comprehensive partitioning scheme is suggeste

Fusion of sentence embeddings for news retrieval

The availability of a vast quantity of information from news channels and social media, make it often difficult to find and follow specific events. This applies to both casual readers and to intelligence and emergency response analysts. In particular, the latter need to find and process relevant information within sense-making, situation and impact assessment processes. The automatic retrieval and tracking of news has been addressed by a good number of works in the information retrieval literature. However, there is a strong potential for introducing automatic systems employing information fusion methods and techniques to assist decision makers. In the field of deep learning, several techniques for text encoding have been proposed, which have allowed significant progress also in the field of news retrieval and ranking. The objective of this paper is to explore the usage and combination of different pre-trained sentence embeddings, including multimodal ones, obtained from different parts of text that compose a news story. This in order to understand which type of technique is best for encoding the different information available in online news