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Providing commanders with advanced decision aids requires a good understanding of the processes involved, their information requirements, and the development of formal domain models upon which reasoning processes can be based. Ontologies, as formal domain models, constitute a key component to provide a shared understanding of a domain, and have received increasing interest for the building of advanced...
This article provides a suboptimal approach to the measurement update of the state vector and the associated state error covariance in the data assimilation process of airborne material dispersion systems, in which the state vector consists of Gaussian puffs and the sensor measurements of the local material concentrations are bar readings. Based on the Bayes rule and numerical quadrature techniques,...
In the context of public place surveillance, the evaluation of available technologies shows that the security bottleneck isn't the surveillance hardware, but rather the real-time analysis and correlation of data provided by various sensors. Also, there is an evident lack of global threat management policy. In this paper, we present an implementation of an event based inference technology called complex...
Defence R&D Canada has been studying the military applications of hyperspectral imagery for a number of years. In other unrelated efforts, the Canadian remote sensing community has also been active in developing hyperspectral algorithms for civilian use. This civilian technology has many potential military applications. In an effort to demonstrate the potential of these defence and civilian technologies...
Today due to the importance and necessity of implementing security systems in homes and buildings with the capability of higher certainty and lower cost, sensor fusion methods as applicable and high performance methods are attracting the researchers' attention. In this paper, the application of Dempster-Shafer evidential theory and the more general and newer one Dezert-Smarandache theory for implementing...
In this paper, we present the challenges that will be faced in maintaining Arctic domain awareness and the Arctic C4ISR issues that will result from these challenges. We have discussed the characteristics of the legacy client-server system and how it limits the exploitation of all available data. The characteristics of a Service-oriented Architecture that could address some of these issues are presented...
This paper describes a novel technique to obtain radar biases estimates that can effectively reduce mismatches in track association algorithms. This is accomplished by matching ship-borne radar images to geo-referenced satellite images. The matching is performed through the minimization of the averaged partial Hausdorff distance between data points in each image. The minimization rapidly yields robust...
Recently, several approaches have been proposed to merge possibly contradictory belief bases. This paper focuses on max-based merging operators applied to incommensurable ranked belief bases. We first propose a characterization of a result of merging using Pareto-like ordering on a set of possible solutions. Then we propose two equivalent ways to recover the result of merging. The first one is based...
High tempo battlefield requirements, rapidly evolving communications/information technologies and the need to include legacy components, call for a system-of- systems engineering approach in the development of data fusion enabled networks (DFEN). System-of- systems engineers are concerned with large scale interdisciplinary issues combining multiple, heterogeneous, distributed systems that are embedded...
The construction of belief networks is a widely used methodology for high level fusion modeling. While some of the components of a belief network deal with ambiguous (probabilistic) data, others may deal with vague (possibilistic) data. Given the need to represent both probabilistic and possibilistic components in a single belief network, a framework and toolset for building Hybrid networks, utilizing...
In this paper, we address the problem of representing domain knowledge for situation awareness in a security application. While ontologies are appropriate for describing taxonomical knowledge, they cannot express more complex knowledge such as entailments. In this paper, we describe how domain knowledge can be encoded through OWL ontologies and SWRL rules in order to reason about the entities and...
Video target tracking is a complex task, specially when the tracking system is expected to work well in different scenarios. For this reason, this paper proposes an architecture based on a two layer image-processing modules: general tracking layer (GTL) and context layer (CL). GTL describes a generic multipurpose tracking process for video surveillance systems. CL is designed as a symbolic reasoning...
In order to manage situations efficiently, commanders need to be aware of possible future events that might occur. They also need to be aware of the relative probabilities of different events, so that they know which events to take into account when making plans of their own. In this paper, we describe a concept prototype that was developed at FOI during 2006 that helps commanders do these tasks....
Data assimilation in the context of puff based dispersion models is studied. A representative two dimensional Gaussian puff atmospheric dispersion model is used for the purpose of testing and comparing several data assimilation techniques. A continuous nonlinear observation model, and a quantized probabilistic nonlinear observation model, are used to simulate the measurements. The quantized model...
The proposed new fusion algorithm is based on the finite Ridgelet transform(FRIT) and PCA. FRIT could capture two and higher dimensional singularity is analyzed. FRIT is used to decompose the image into low and high frequency components. The PCA method is used to fuse the low frequency coefficients. And for the high frequency coefficients, the maximum-method and the region consistency check are adopted...
In multi-sensor multi-target bearings-only tracking we often see false intersections of bearings known as ghosts. When the bearing measurements from each sensor have been associated to form sequences termed threads, the problem is to associate pairs of threads to identify the true target intersections. In this paper we present two algorithms: (i) classical bayesian thread association (CBTA) and (ii)...
An alternating directions method is presented for joint maximum a posteriori estimation of target track and sensor field using bistatic range data. The algorithm cycles over two sub-algorithms: one improves the target state estimate conditioned on sensor field state, and the other improves the sensor field state estimate conditioned on target state. Nonlinearities in the sub-algorithms are mitigated...
Multi-sensor systems in automotive safety applications and sensor data fusion have become very popular in recent years. Sensors on board cars and active safety applications are increasing in number and the need to define a common method for object extraction and serving these applications has been recognized. Authors propose a high level fusion approach suitable for automotive sensor networks with...
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