Forsvarets Forskningsinstitutt FFI

Kjeller, Norway

Forsvarets Forskningsinstitutt FFI

Kjeller, Norway
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Aardal O.,Forsvarets Forskningsinstitutt FFI | Hamran S.-E.,Forsvarets Forskningsinstitutt FFI | Berger T.,Forsvarets Forskningsinstitutt FFI | Paichard Y.,Forsvarets Forskningsinstitutt FFI
2011 IEEE Biomedical Circuits and Systems Conference, BioCAS 2011 | Year: 2011

Heartbeats can be measured at a distance using radar to record the chest movements. The physiological motion appear as modulations in both phase and amplitude in the radar recording. In this paper, a single reflector model of the heartbeat is used to estimate the chest motion and find the movement in millimeters. Experimental results from 10-18GHz measurements are presented, and the validity of the estimation discussed. © 2011 IEEE.

Ronning H.T.,Norwegian University of Life Sciences | Madslien E.H.,Forsvarets forskningsinstitutt FFI | Asp T.N.,Norwegian University of Life Sciences | Granum P.E.,Norwegian University of Life Sciences
Food Additives and Contaminants - Part A Chemistry, Analysis, Control, Exposure and Risk Assessment | Year: 2015

Lichenysin produced by 53 different Bacillus licheniformis strains has been structurally examined with a qualitative liquid chromatography-tandem mass spectrometry (LC-MS/MS) method using quadrupole-time-of-flight mass spectrometry. The same lichenysin isoforms are produced from all strains, indicating that the growth conditions have a stronger influence on the lipopeptide production than the genotype. A rapid method for the quantification of lichenysin from bacterial cell cultures with LC-MS/MS after a simple methanol extraction has been refined. For the first time commercially available lichenysin has been used as calibrant, making quantification more accurate. The trueness for C15-lichenysin has been improved to 94% using matrix-matched calibration with lichenysin compared with 30% using solvent calibration with surfactin. The quantitative method was fully validated based on Commission Decision 2002/657/EC. The LOD of the method was below 1 µg g– 1 and the repeatability ranged from 10% to 16%. © 2015 Taylor & Francis.

Madslien E.H.,Forsvarets Forskningsinstitutt FFI | Olsen J.S.,Forsvarets Forskningsinstitutt FFI | Granum P.E.,Section for Food Safety | Blatny J.M.,Forsvarets Forskningsinstitutt FFI
BMC Microbiology | Year: 2012

Background: Bacillus licheniformis has for many years been used in the industrial production of enzymes, antibiotics and detergents. However, as a producer of dormant heat-resistant endospores B. licheniformis might contaminate semi-preserved foods. The aim of this study was to establish a robust and novel genotyping scheme for B. licheniformis in order to reveal the evolutionary history of 53 strains of this species. Furthermore, the genotyping scheme was also investigated for its use to detect food-contaminating strains. Results: A multi-locus sequence typing (MLST) scheme, based on the sequence of six house-keeping genes (adk, ccpA, recF, rpoB, spo0A and sucC) of 53 B. licheniformis strains from different sources was established. The result of the MLST analysis supported previous findings of two different subgroups (lineages) within this species, named A and B Statistical analysis of the MLST data indicated a higher rate of recombination within group A. Food isolates were widely dispersed in the MLST tree and could not be distinguished from the other strains. However, the food contaminating strain B. licheniformis NVH1032, represented by a unique sequence type (ST8), was distantly related to all other strains. Conclusions: In this study, a novel and robust genotyping scheme for B. licheniformis was established, separating the species into two subgroups. This scheme could be used for further studies of evolution and population genetics in B. licheniformis. © 2012 Madslien et al.; licensee BioMed Central Ltd.

Wiig M.S.,Forsvarets Forskningsinstitutt FFI | Krogstad T.R.,Forsvarets Forskningsinstitutt FFI | Midtgaard O.,Forsvarets Forskningsinstitutt FFI
2012 IEEE/OES Autonomous Underwater Vehicles, AUV 2012 | Year: 2012

This paper presents a concept and algorithms to detect, classify and identify mine-like objects within a single mission with an autonomous underwater vehicle. The autonomous mine hunting concept has been developed for the HUGIN series of vehicles. First, the operation area is surveyed either with a synthetic aperture sonar or a side-scanning sonar. During the survey, mine-like objects are detected and classified in the data using algorithms for automatic target recognition. When the survey is complete, a framework for autonomy initiates a fusion of the targets and starts the automatic planning of a mission plan for target identification. The autonomous mine hunting concept is a part of the development of a framework for advanced autonomy on HUGIN, the HUGIN autonomy layer. Implementation of this framework will reduce the risk of long-term AUV missions, and will provide intelligent vehicle behavior not only to re-inspect interesting objects and areas, but also to preserve vehicle safety, navigational accuracy and mission goals. © 2012 IEEE.

Madslien E.H.,Forsvarets Forskningsinstitutt FFI | Ronning H.T.,Section for Food Safety | Lindback T.,Section for Food Safety | Hassel B.,Forsvarets Forskningsinstitutt FFI | And 2 more authors.
Journal of Applied Microbiology | Year: 2013

Aims: The aim of this study was to elucidate the prevalence of lichenysin production in Bacillus licheniformis and to see whether this feature was restricted to certain genotypes. Secondly, we wanted to see whether cytotoxicity reflected the measured levels of lichenysin. Methods and Results: Fifty-three genotyped strains of B. licheniformis, representing a wide variety of sources, were included. lchAA gene fragments were detected in all strains by polymerase chain reaction (PCR). All 53 strains produced lichenysins with four molecular masses as confirmed by LC-MS/MS (liquid chromatography-tandem mass spectrometry) analysis. The amounts of lichenysin varied more than two orders of magnitude between strains and were irrespective of genotype. Finally, there was a strong association between lichenysin concentrations and toxicity towards boar spermatozoa, erythrocytes and Vero cells. Conclusions: Lichenysin synthesis was universal among the 53 B. licheniformis strains examined. The quantities varied considerably between strains, but were not specifically associated with genotype. Cytotoxicity was evident at lichenysin concentrations above 10 μg ml-1, which is in accordance with previous studies. Significance and Impact of Study: This study might be of interest to those working on B. licheniformis for commercial use as well as for authorities who make risk assessments of B. licheniformis when used as a food and feed additive. © 2013 The Society for Applied Microbiology.

Madslien E.H.,Forsvarets Forskningsinstitutt FFI | Madslien E.H.,Norwegian University of Life Sciences | Granum P.E.,Norwegian University of Life Sciences | Blatny J.M.,Forsvarets Forskningsinstitutt FFI | Lindback T.,Norwegian University of Life Sciences
BMC Microbiology | Year: 2014

Background: L-alanine, acting through the GerA receptor, was recently found to be an efficient germinant in Bacillus licheniformis ATCC14580/DSM13. Results: In this study, we show that several of 46 examined B. licheniformis strains germinate remarkably slower than the type strain when exposed to L-alanine. These strains are not necessarily closely related, as determined by MLST (multi-locus sequence typing). Three of the slow-germinating strains were further examined in order to see whether nucleotide substitutions in the gerA sequences were responsible for the slow L-alanine germination. This was performed by complementing the transformable type strain derivate MW3ΔgerAA with gerA variants from the three slow-germinating strains; NVH1032, NVH1112 and NVH800. Conclusions: A wide selection of B. licheniformis strains was evaluated for L-alanine-induced germination efficiency. Our results show that gerA substitutions could only partially explain why spores of some B. licheniformis strains responded slower than others in the presence of L-alanine. © 2014 Madslien et al.; licensee BioMed Central Ltd.

Dullum O.S.,Forsvarets Forskningsinstitutt FFI
Proceedings - 29th International Symposium on Ballistics, BALLISTICS 2016 | Year: 2016

When at bullet moves along a rifled barrel, the engraving of the jacket or the driving band will cause some degree of abrasion which is emitted as metallic dust. This effect is especially prominent in small caliber guns. For small arms bullets, the jacket surface is exclusively made of tombac for which the emitted dust will consist of copper and some zinc. Inhalation of these metals may cause severe health problems among the users. Although the illness is temporary, the soldiers may be unfit to maintain his task for several hours after exposure. This paper documents a series of measurements for which the amount of emitted dust has been measured. Steel-cored projectiles may have more than 100% more dust emission than lead-cored ones. However, the amount does not depend solely on the ammunition, but the shape of the barrel is also a significant factor.

Aardal O.,Forsvarets Forskningsinstitutt FFI | Hamran S.-E.,Forsvarets Forskningsinstitutt FFI | Berger T.,Forsvarets Forskningsinstitutt FFI | Hammerstad J.,Forsvarets Forskningsinstitutt FFI | Lande T.S.,P.O. Box 1080
2011 IEEE Radio and Wireless Week, RWW 2011 - 2011 IEEE Radio and Wireless Symposium, RWS 2011 | Year: 2011

Cardiopulmonary motion can be detected from a distance using radar. Which frequencies that are best suited for detecting heartbeats or respiration is connected to the radar cross section (RCS) of the physiological motion. In this paper, we investigate the RCS of human heartbeats and respiration in the frequency range 500MHz to 3GHz through calibrated radar recordings of two persons. © 2010 IEEE.

Berger T.,Forsvarets Forskningsinstitutt FFI | Hamran S.-E.,Forsvarets Forskningsinstitutt FFI
IEEE National Radar Conference - Proceedings | Year: 2012

In this paper we compare the resulting images using three autofocusing techniques and navigation data from measurements performed from a rooftop rail system with a C-band radar developed at FFI. We describe the system and its characteristics, and we apply the autofocusing techniques to images of a scene containing a corner reflector and other targets. The results show that all autofocusing techniques improve the quality of the images, and the methods using a single prominent point give better results than the more general phase gradient autofocus method. The experiments also show that the measured data can be used to reliably estimate the range displacements of the aperture over the flight path when a fixed point in the scene is used a reference. © 2012 IEEE.

Maseng T.,Forsvarets Forskningsinstitutt FFI
IFIP Wireless Days | Year: 2011

By applying information theory to the analysis of a cellular system, it has been shown that it is a useful idea to reuse all the frequency bands in the adjacent cell (frequency reuse factor 1) and use the most robust modulation scheme at the cell boundary. This is not a surprising result since this is done in LTE and other systems like WIMAX and DTT. How this was derived by means of simple formulas is hopefully original and should provide some useful insights. The analysis has been done for the up link which is normally more critical than down link. As expected, the capacity of the cell increases as the propagation exponent increases since there is less interference between the cells using the same frequency and only the interference from other cells using the same frequency limits the capacity - not the thermal noise. The analysis presented is not limited to a particular system like LTE. © 2011 IEEE.

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