| 1. |
- Bull, Peter, et al.
(författare)
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Förstudie obemannade farkoster
- 2012
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Rapport (populärvet., debatt m.m.)abstract
- Obemannade farkoster används allt oftare, och i allt fler roller, i dagens kon- flikter. Denna rapport ger en bred överblick över området militära obemannade farkoster, samt rekommendationer för inriktningen av framtida FoU-satsningar inom området.Överblicken över området har fokus på både system, förmågor och verksam- heter som är relevanta för Försvarsmakten. Genom att låta de insatsförmågor som definieras i FMUP (Försvarsmaktens utvecklingsplan) gå som en röd tråd genom rapporten, både när specifika system diskuteras och när möjliga scena- rier där obemannade farkoster kan vara till nytta beskrivs, har vi försökt hålla både bredd och relevans i dokumentet.Rekommendationerna vilar på en genomgång av de inriktningsdokument som producerats i Försvarsmakten, t.ex. Perspektivplanneringen och FMUP, besök vid de enheter som dagligen använder obemannade farkoster, UAV-enheten i Karlsborg och Swedec i Eksjö, samt den områdesöverblick som nämns ovan. Slutsatserna är att den effektivaste kompetensuppbyggnaden och kunskapsöver- föringen fås om man skapar breda tvärvetenskapliga projekt inom respektive systemkategori (UAV, UGV, etc) med nära kontakter till materielförsörjnings- processen och perspektivplaneringen. Dessa kan samla kompetensen inom FHS och FOI, övervaka forskningsfronten genom att bevaka tävlingar, konferenser samt delta i internationella samarbeten, samt överföra det samlade resultaten till Försvarsmakten genom demonstrationer av verkliga eller simulerade delsy- stem och interaktiva simuleringar av hela system. Just systemsimuleringar kan göras särskilt realistiska, eftersom interaktionen med de riktiga obemannade systemen till stor del sker igenom kontrollstationernas datorer. På så sätt ska- pas en känsla för både hot och möjligheter med de nya systemen, vilket gagnar både taktikutveckling och materielprocesser.
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| 2. |
- Feldmann, M., et al.
(författare)
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Economic and durable design of composite bridges with integral abutments
- 2010
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Rapport (refereegranskat)abstract
- In the design and construction of bridges, questions of sustainability, maintenance and durability are becoming more and more important for European road administrations, in addition to safety and serviceability issues. Therefore integral abutment bridges are becoming highly attractive to designers, constructors and road administrations, as they tend to be less expensive to build, easier to maintain and more economical to own over their life time. Bearings and joints are main sources of maintenance costs during a lifetime. These costs vanish because the bridges are joint- and bearing-free. However, this very advantage complicates the design compared to conventional bridges in some crucial respects. Combined with the fact that most European countries have only limited experience with integral bridges to date, this leads to a reluctance of road administrations to use this bridge type. Thus the main objective of the project is to experimentally and theoretically investigate the behaviour of critical points of integral abutment bridges. Regarding the soil-structure interaction, recommendations are elaborated based on monitoring results as well as previous research and monitoring campaigns. Conventional HP piles and sheet piles are investigated as a foundation. Furthermore a hinged HP connection is developed to decrease the stresses in the pile system. An investigation of the design and construction of the slab to pavement approach is also carried out to avoid major damages to the structure. Finally the most important information is condensed into the essential features in form of a 'Design guide for composite bridges with integral abutments'
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| 3. |
- Nilsson, Annika M. K., et al.
(författare)
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T-matrix computations of light scattering by red blood cells
- 1998
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- The electromagnetic far field, as well as near field, originating from light interaction with a red blood cell (RBC) volume equivalent spheroid, were analyzed utilizing T-matrix theory. This method is a powerful tool which enables the influence of cell shape on the angular distribution of scattered light to be studied. General observations were that the three-dimensional shape, as well as optical thickness apparent to the incident field, affect the forward scattering. The back scattering was influenced by the shape of the surface facing the incident beam. Furthermore, sphering as well as elongation of an oblate shaped RBC into a volume equivalent sphere or prolate shaped spheroid, respectively, were theoretically modeled in order to imitate physiological phenomena caused, e.g., by sphering agents, heat or increased shear stress of flowing blood. Both sphering and elongation were shown to decrease the intensity of the forward directed scattering, thus yielding lower g-factors. The sphering made the scattering pattern independent of the azimuthal scattering angle φs, while the elongation induced more apparent φs-dependent patterns. The light scattering by an RBC volume equivalent spheroid, was thus found to be highly influenced by the shape of the scattering object. A near-field radius, rnf, was evaluated as the distance to which the maximum intensity of the total near field had decreased to 2.5 times that of the incident field. It was estimated to 2-24.5 times the maximum radius of the scattering spheroid, corresponding to 12-69 µm. When the absorption properties of a red blood cell were incorporated in the computations, the near-field radius was only slightly reduced by 0.2-0.6 times the maximum radius. As the near-field radius was shown to be larger than a simple estimation of the distance between the RBCs in whole blood, the assumption of independent scattering, frequently employed in optical measurements on whole blood, seems inappropriate. This also indicates that results obtained from diluted blood, cannot be extrapolated to whole blood, by multiplying with a simple concentration factor.
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