Christoffer Brax

Learn More
We extend the State-Based Anomaly Detection approach by introducing precise and imprecise anomaly detectors using the Bayesian and credal combination operators, where evidences over time are combined into a joint evidence. We use imprecision in order to represent the sensitivity of the classification regarding an object being normal or anomalous. We(More)
The Network Coordinating Council (NCC) #4 continuous ambulatory peritoneal dialysis (CAPD) study was designed to gather basic demographic information and analyze selected outcome parameters on all patients started on CAPD in Southern California/Southern Nevada. Between early 1979 and Dec 31, 1983, 775 patients were enrolled in the study for a total(More)
In this paper we propose an approach for detecting anomalies in data from visual surveillance sensors. The approach includes creating a structure for representing data, building ldquonormal modelsrdquo by filling the structure with data for the situation at hand, and finally detecting deviations in the data. The approach allows detections based on the(More)
The maritime industry is experiencing one of its longest and fastest periods of growth. Hence, the global maritime surveillance capacity is in a great need of growth as well. The detection of vessel activity is an important objective of the civil security domain. Detecting vessel activity may become problematic if audit data is uncertain. This paper aims to(More)
The use of technology to assist human decision making has been around for quite some time now. In the literature, models of both technological and human aspects of this support can be identified. However, we argue that there is a need for a unified model which synthesizes and extends existing models. In this paper, we give two perspectives on situation(More)
The increased societal need for surveillance and the decrease in cost of sensors have led to a number of new challenges. The problem is not to collect data but to use it effectively for decision support. Manual interpretation of huge amounts of data in real-time is not feasible; the operator of a surveillance system needs support to analyze and understand(More)
The use of technology to assist human decision making is not a novel idea. However, we argue that there is a need for a unified model which synthesizes and extends existing models. In this paper, we give two perspectives on situation analysis: a technological perspective and a human perspective. These two perspectives are merged into a unified situation(More)
In the presentation the five-year experiences from the yearly 24 hours software engineering competition held at University of Skövde is presented. The outline for the competition is briefed and architectural and design issues are in focus. The competition is divided into two phases where the first is to develop the software the second is too compete(More)