| 1. |
|
|
| 2. |
- Forssén, Jens, et al.
(författare)
-
Auralization of traffic noise within the LISTEN project : Preliminary results for passenger car pass-by
- 2009
-
Ingår i: Euronoise 2009. - Edinburgh : Institute of Acoustics.
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Auralization of future traffic noise scenarios would be a valuable tool for city planners, noise consultants and decision makers, since it would make it possible to evaluate various noise mitigation solutions already at the planning stage. The main goal of the Swedish multidisciplinary research project LISTEN is to develop such a tool. In the present paper, auralizations of a single pass-by of a passenger car are investigated with respect to different simulation approaches, and the methodologies behind the approaches are described. Three listening experiments were conducted in order to perceptually evaluate the auralizations. The results showed a high degree of perceptual agreement between real and auralized sounds. However, slight differences between real and auralized sounds were found for perceived realism, annoyance and speed of vehicles, which calls for further improvements of the auralizations.
|
|
| 3. |
- Hanson, Maj, 1939, et al.
(författare)
-
Magnetic properties of epitaxial Ni(001) films and sub-micron particles
- 2001
-
Ingår i: Journal of Magnetism and Magnetic Materials. - 0304-8853 .- 1873-4766. ; 236, s. 139-50
-
Tidskriftsartikel (refereegranskat)abstract
- The magnetic properties of Ni particles with well-defined geometry, prepared by electron lithography from epitaxial Ni(001) films of thickness 50 and 60 nm were studied. The particles were circles with diameters 0.6 m and rectangles with sides 0.9 m and 0.3 m, that were positioned in square and rectangular lattices, having lattice constants about twice the particle dimensions. Reference samples and particles with the lattices oriented along the [100] and [110] directions were prepared. Hysteresis curves were obtained for particles and reference samples, in the field range 2T at temperatures between 50 and 300 K. The particles were further imaged by magnetic force microscopy. The coercivities of the particles are about the same as that of the reference samples, being of the order of 10 mT at room temperature and increasing with decreasing temperature. This may be explained by the temperature dependence of the magnetic anisotropy of the Ni film, estimated to K1=-12.5, -12.8 and -87.6 kJ m-3 at 295, 250 and 50 K, respectively. Whereas the hysteresis curves of the particles are governed by the intrinsic properties of the starting film in low fields, the decreased lateral size influences the behaviour in higher fields as demagnetization effects and features characteristic for annihilation and nucleation of domain walls. One of the samples, rectangles with the long axis alone the [110] direction, has a significantly higher remanence and coercivity than the others. The magnetic images show that the demagnetized state of this sample comprises both single-domain and multidomain particles. Corresponding images showed only multidomain particles in all other samples. Thus it was concluded that the actual size (0.9 m0.3 m50 nm) is close to the critical size for single domains in Ni
|
|
| 4. |
|
|
| 5. |
- Hellsing, M, et al.
(författare)
-
ToF-SIMS imaging of dopant diffusion in optical fibers
- 2003
-
Ingår i: Applied Surface Science. - 0169-4332 .- 1873-5584. ; 203, s. 648-651
-
Tidskriftsartikel (refereegranskat)abstract
- Applications of optical fibers in telecommunication and sensing are rapidly emerging where the fiber properties are related to the controlled addition of dopants such as germanium, phosphorous, fluorine and erbium. The modern ToF-SIMS instrument, with its high sensitivity and high lateral resolution, has shown to be an excellent tool to directly analyze cross-sections of as-manufactured fibers. The present work describes ToF-SIMS imaging of the dopant distribution in fluorine, germanium and rare-earth doped fibers where dopants are confined to a few mum in the core. The increased fluorine diffusion in the fluorine doped fibers due to chemical reactions with hydroxyl groups was examined. This process is utilized in the manufacture of thermally stable chemical composition fiber Bragg gratings. We were able to produce ToF-SIMS elemental images with a lateral resolution around 0.5 mum showing the detailed distribution of the dopants.
|
|
| 6. |
|
|
| 7. |
- Myren, N, et al.
(författare)
-
In-fiber electrode lithography
- 2004
-
Ingår i: Journal of the Optical Society of America B (Optical Physics. ; 21:12, s. 2085-88
-
Tidskriftsartikel (refereegranskat)
|
|
| 8. |
- Nilsson, L. -E, et al.
(författare)
-
Specialty Single-Mode Fibers
- 2007
-
Ingår i: Specialty Optical Fibers Handbook. - : Elsevier. - 9780123694065 ; , s. 165-193
-
Bokkapitel (refereegranskat)abstract
- This chapter provides an overview of unusual multifunctional, specialty single-mode fibers-macrohole fibers, multicore fibers, fibers with internal electrodes, and fibers for high-temperature resistant fiber Bragg gratings. Macrohole fibers belong to the group of microstructured fibers, which encompass a wide variety of fibers with air holes or other structures extending in the axial direction. Functions performed using macrostructured fibers include supercontinuum generation in tapered hole fibers, dispersion management, fibers with decreased bend loss for compact optical fiber wiring, and fibers for polarimetric sensing, and lasers. The introduction of materials in the holes adds the possibility of manipulating the guiding properties of the fiber. This can be achieved by interaction of the guided mode with actively controllable materials in the holes or by using the inserted materials for other active functions, such as a metal electrode to implement electro-optic control of the fiber. The proposed applications for multicore fibers span over lasers and amplifiers, transport fibers for broadband communications, passive, and active fiber optic components such as filters, multiplexers, and various kinds of sensors. The ultimate multicore fiber is the image fiber used in endoscopes and other such devices.
|
|
| 9. |
- Nilsson, Mats E., et al.
(författare)
-
Perceptual evaluation of a real time auralization tool
- 2009
-
Ingår i: Euronoise 2009. - Edinburgh : Institute of Acoustics.
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- This paper illustrates the use of psychoacoustic methods and multivariate statistics for perceptual evaluation of auralizations. In four experiments, listeners assessed binaural recordings and auralizations of the same sound sources, using a newly developed tool for real time auralization of room acoustics. The recorded signals were music and speech reproduced by a loudspeaker in a classroom and an auditorium. Listeners assessed (a) perceived realism of recorded versus auralized sounds, (b) perceived similarity of pair wise presented sounds, (c) perceived intelligibility of spoken words, and (d) a set of perceptual attributes of sounds, using eight semantic differential scales. The results showed that listeners could discriminate between recorded and auralized sounds, although they were perceived as equally realistic. Analysis showed that auralized sounds were perceived as less full and more metallic than recorded sounds, and auralized speech were easier to catch (hear, understand) than the recorded speech. The next step of this ongoing research is to conduct psychoacoustic analysis in order to identify acoustic differences between recorded and auralized sounds that may explain their perceptual differences.
|
|
| 10. |
|
|
