| 1. |
|
|
| 2. |
- Bengtsson, Magnus, et al.
(author)
-
Fluorescence lidar imaging of fungal growth on high-voltage outdoor composite insulators
- 2005
-
In: Optics and Lasers in Engineering. - : Elsevier BV. - 0143-8166 .- 1873-0302. ; 43:6, s. 624-632
-
Journal article (peer-reviewed)abstract
- Remote fluorescence imaging of fungal growth on polymeric high-voltage insulators was performed using a mobile lidar system with a laser wavelength of 355 nm. Insulator areas contaminated by fungal growth could be distinguished from clean surfaces and readily be imaged. The experiments were supported by detailed spectral studies performed in laboratory using a fibre-optic fluorosensor incorporating an optical multi-channel analyser system (OMA) and a nitrogen laser emitting radiation at 33 7 nm.
|
|
| 3. |
- Bengtsson, Magnus, et al.
(author)
-
Fungus covered insulator materials studied with laser-induced fluorescence and principal component analysis
- 2005
-
In: Applied Spectroscopy. - : SAGE Publications. - 0003-7028 .- 1943-3530. ; 59:8, s. 1037-1041
-
Journal article (peer-reviewed)abstract
- A method combining laser-induced fluorescence and principal component analysis to detect and discriminate between algal and fungal growth on insulator materials has been studied. Eight fungal cultures and four insulator materials have been analyzed. Multivariate classifications were utilized to characterize the insulator material, and fungal growth could readily be distinguished from a clean surface. The results of the principal component analyses make it possible to distinguish between algae infected, fungi infected, and clean silicone rubber materials. The experiments were performed in the laboratory using a fiber-optic fluorosensor that consisted of a nitrogen laser and an optical multi-channel analyzer system.
|
|
| 4. |
- Bengtsson, Magnus, et al.
(author)
-
Lidar fluorescence measurements of algal growth on electrical insulators
- 2003
-
In: 2003 Conference on Lasers and Electro-Optics Europe (CLEO/Europe 2003) (IEEE Cat. No.03TH8666). - 0780377346 ; , s. 473-473
-
Conference paper (peer-reviewed)abstract
- Fluorescence measurements using lidar techniques have been shown to be useful for monitoring of algal growth on e.g. historical monuments. In this experiment similar measurements were performed on electrical insulators to examine the correlation between algal growth and the quality of the insulator, a factor of importance in the high-voltage grid management
|
|
| 5. |
- Bengtsson, Magnus, et al.
(author)
-
Remote laser-induced breakdown spectroscopy for the detection and removal of salt on metal and polymeric surfaces
- 2006
-
In: Applied Spectroscopy. - : SAGE Publications. - 1943-3530 .- 0003-7028. ; 60:10, s. 1188-1191
-
Journal article (peer-reviewed)abstract
- The detection of contamination such as salt in outdoor high-voltage insulator systems and its subsequent removal are vital for a reliable transmission of electric power. Remote detection of salt on a copper metal surface was carried out by using a mobile laser-induced breakdown spectroscopy (LIBS) Lidar system with a laser wavelength of 355 nm. Detection of salt on a polymeric high-voltage insulator was obtained when an additional lens was inserted into the beam path, and the number of photons that was detected could be calculated by using a calibrated white light source. Ablative cleaning could readily be carried out with LIBS and was verified by observing the disappearance of the sodium D-line emission.
|
|
| 6. |
|
|
| 7. |
- Dernfalk, Andreas, 1975, et al.
(author)
-
Laser-induced fluorescence spectroscopy for detection of biological contamination on composite insulators
- 2003
-
In: In Proc. 13th International Symposium on High Voltage Engineering, Delft, Netherlands.
-
Conference paper (peer-reviewed)abstract
- A new technique for remote detection of biological contamination on high-voltage outdoor insulators has been investigated. The technique, which is based on laser-induced fluorescence (LIF) spectroscopy, has been applied to study surfaces of real silicon rubber insulators from a distance of approximately 60 m. Measurements were performed outdoors on a number of clean, as well as, biologically contaminated insulators. Several types of biological contamination were included, as five of the studied insulators had become covered when installed in Sweden, and another three had been contaminated by fungal growth in laboratory. Fluorescence spectra obtained from the surfaces of the described insulators are presented and the applicability of the technique is discussed and compared with photographic methods.
|
|
| 8. |
|
|
| 9. |
- Grönlund, Rasmus, et al.
(author)
-
Remote LIBS and Raman imaging for assessment of cultural heritage
- 2005
-
In: 2005 Conference on Lasers and Electro-Optics Europe. - 0780389743 ; , s. 684-684
-
Conference paper (peer-reviewed)abstract
- In this paper, we propose to perform remote laser-induced breakdown spectroscopy (LIBS) and Raman imaging of historical monuments to assess the state of a building. The lidar system is equipped with a Nd:YAG pumped optical parametrical oscillator (OPO) system, allowing laser radiation in the wavelength range 220 nm-4 μm. The laser radiation can be sent through a roof-top dome which can steer the radiation onto the point of interest
|
|
