Swedish Defence Research Agency

About: Swedish Defence Research Agency is a government organization based out in Stockholm, Sweden. It is known for research contribution in the topics: Radar & Laser. The organization has 1413 authors who have published 2731 publications receiving 56083 citations. The organization is also known as: Totalförsvarets forskningsinstitut.

Planning for future sea-level rise in Swedish municipalities

Abstract: A warmer climate leads to rising sea levels. Despite uncertainties about how rapid and substantial future sea-level rise (SLR) will be, society needs to prepare and adapt. This study examines the state of planning for future SLR in Sweden by surveying 33 coastal municipalities in southern Sweden and interviewing local, regional and national authorities with relevant accountability. The results reveal that there are considerable gaps in current planning for SLR. Almost one-third of municipalities lack guiding planning documents for SLR, and more than two-thirds do not discuss SLR beyond 2100. We argue that the prevailing uncertainty and ambiguity in assessments of future SLR is problematic within a traditional “predict-then-act” paradigm, and that robust approaches, such as scenario planning, can reduce many of these problems.

Evaluation of an Information System in an Information Seeking Process

Abstract: This paper presents a holistic evaluation of an operational information system that employs the Boolean search technique. An equal focus is laid on both the system (system perspective) and its users (user perspective) in the actual environment where the system and its users are functioning (contextuality). In addition to these research objectives, the study has a methodological objective to test an evaluation approach developed by Borlund [1] in a real life setting. Our evaluation methodology involves triangulation (pre-search questionnaires; search log; post-interviewing) as well as novel interactive performance measures, such as the Ranked Half-Life measure and the Satisfaction and Novelty perception by users supplementing the traditional Precision. The study confirms the finding of earlier research and reveals the discrepancy between the evaluation results according to the system and the user perspectives. More specifically, the system performed better when evaluated from the user perspective than from the system perspective.

Development of a fluorescence-based point detector for biological sensing

Abstract: This paper presents the status of an ongoing development of a point detector for biological warfare agent sensing based on ultraviolet laser-induced fluorescence from single particles in air. The detector will measure the fluorescence spectra of single particles in a sheath flow air beam. The spectral detection part of the system consists of a grating and a photomultiplier tube array with 32 channels, which measure fluorescence spectra in the wavelength band from 300 nm to 650 nm. The detector is designed to measure laser induced fluorescence from single laser pulses and has been tested by measuring fluorescence from simulants of biological warfare agents in aqueous solution. The solutions were excited with laser pulses at the wavelengths of 293 nm and 337 nm. The paper also presents preliminary results on the sheath flow particle injector and time-resolved measurements of fluorescence from biological warfare agent simulants in solution.

A new approach to derive emission requirements on APD in order to protect digital communication systems

Abstract: Amplitude probability distribution (APD) has been proposed within CISPR as a measure of the emitted electromagnetic energy from electrical equipment. APD describes the envelope statistics of a disturbance from the IF filter of the measurement receiver and is in many ways a suitable model of nonGaussian noise, when determining its impact on a digital communication system. In an earlier paper, the connection between the APD of a disturbance and its effect on a digital receiver was presented. However, to derive a maximum allowed APD out of a maximum allowed bit error probability is a non-trivial problem. Unfortunately, this is exactly the issue when emission requirements should be related to the APD. This paper presents a possible way to put requirements on the APD in order to protect digital communication systems. By letting a measured APD of a disturbance lay below the requirements, the impact on a variety of receivers are guaranteed to not exceed the maximum bit error probability

Detection of vehicles in shadow areas

Abstract: This paper presents a new method to automatically detect occluded vehicle in semi or deep shadow areas using combined very high resolution (VHR) 3D LIDAR and hyperspectral data The proposed shape/spectral integration (SSI) decision fusion algorithm was shown to outperform the spectral based anomaly algorithm mainly in deep shadow areas The fusion of LIDAR DSM data with spectral data is useful in the detection of vehicles in semi and deep shadow areas The utility of shape information was shown to be a way to enhance spectral target detection in complex urban scene