SwePub
Sök i SwePub databas

  Utökad sökning

Träfflista för sökning "WFRF:(Gustafsson Mats) "

Sökning: WFRF:(Gustafsson Mats)

  • Resultat 651-660 av 982
Sortera/gruppera träfflistan
   
NumreringReferensOmslagsbildHitta
651.
  • Larsson, Bertil, et al. (författare)
  • Nondestructive detection of decay in living trees
  • 2004
  • Ingår i: Tree Physiology. - : Oxford University Press (OUP). - 1758-4469 .- 0829-318X. ; 24:7, s. 853-858
  • Tidskriftsartikel (refereegranskat)abstract
    • We used a four-point resistivity method to detect wood decay in living trees. A low-frequency alternating current was applied to the stem and the induced voltage measured between two points along the stem. The effective resistivity of the stem was estimated based on stem cross-sectional area. A comparison within a group of trees showed that trees with butt rot had an effective resistivity that was at least a factor of two lower than that of healthy trees. In tests on several groups of Norway spruce (Picea abies (L.) Karst.) comprising more than 300 trees in total, the method detected butt rot with high accuracy. We validated the method both by measurements and by finite element modeling and simulations.
  •  
652.
  •  
653.
  • Larsson, Christer, et al. (författare)
  • Calibration methods for wideband forward RCS measurements
  • 2010
  • Ingår i: Proceedings of the Fourth European Conference on Antennas and Propagation. - 9781424464319 - 9788476534724 ; , s. 1-5
  • Konferensbidrag (refereegranskat)abstract
    • Calibration is an important part in all radar cross section measurements. Two different approaches to the calibration of forward and extinction cross section measurements are therefore evaluated and discussed in this paper. The first method is the commonly used calibration method employing a calibration target with a known cross section while the second calibration method does not require a calibration target. It is concluded that the method utilizing a calibration target is the most accurate method of the two.
  •  
654.
  •  
655.
  • Larsson, Christer, et al. (författare)
  • Measuring the extinction cross section
  • 2009
  • Ingår i: [Host publication title missing]. - 9781424447534 ; , s. 3510-3513
  • Konferensbidrag (refereegranskat)abstract
    • This paper describes a method to determine the extinction cross section for a very large bandwidth in the microwave region. The method is based on measurements of the radar cross section in the forward direction to calculate the extinction cross section. The method is applicable to samples of arbitrary shape and composition. Coherent background subtraction and time domain gating is used for the frequency range [2.5, 38] GHz to increase the sensitivity. The efficiency of the background subtraction and the accuracy of the measurements are estimated.
  •  
656.
  •  
657.
  •  
658.
  •  
659.
  • Larsson, Christer, et al. (författare)
  • Wideband Measurements of the Forward RCS and the Extinction Cross Section
  • 2013
  • Ingår i: Applied Computational Electromagnetics Society Journal. - 1054-4887. ; 28:12, s. 1145-1152
  • Tidskriftsartikel (refereegranskat)abstract
    • This paper describes the development of a method based on measurements of the radar cross section (RCS) amplitude and phase in the forward direction to determine the extinction cross section for the 2.5 GHz - 38 GHz frequency range using the optical theorem. Forward RCS measurements are technically complicated due to that the direct signal has to be subtracted from the total signal at the receiving antenna in order to extract the forward RCS. The efficiency of this subtraction as a function of time is evaluated. A traditional calibration method using a calibration target and a second method that does not require a calibration target are investigated and compared. The accuracy of the forward RCS measurements is determined using small spheres of different sizes. The spheres have a forward RCS that is straight forward to calculate with good accuracy. The method is also extended to polarimetric measurements on a small helix that are compared with method-of-moments calculations to validate the method.
  •  
660.
  • Larsson, Christer, et al. (författare)
  • Wideband Measurements of the Forward RCS and the Extinction Cross Section
  • 2012
  • Ingår i: [Host publication title missing]. ; , s. 1-6
  • Konferensbidrag (refereegranskat)abstract
    • This paper describes the development of a method based on measurements of the radar cross section (RCS) in the forward direction to determine the extinction cross section for the 2.5 – 38 GHz frequency range. A conventional anechoic chamber designed for monostatic measurements is used for forward RCS measurements. The extinction cross section is then calculated from the measured forward RCS using the optical theorem. The motivation for this study is to develop an experimental method that can be used to verify recent theoretical work which shows that the extinction cross section integrated over all frequencies is related to the static properties of the scatterer. Forward RCS measurements are technically complicated due to the large direct contribution from the transmitting antenna to the received signal. The direct signal has to be subtracted from the total signal at the receiving antenna in order to extract the forward RCS. The efficiency of this subtraction is evaluated in this study by performing long time measurements leading to an estimation of subtraction accuracy as a function of the time between the two measurements. Two calibration methods are investigated. The first method is the traditional calibration method used in most RCS measurements. It uses a target with known RCS as a calibration target to calibrate the target measurement. The second method that is described here does not require a calibration target. It uses a direct path measurement of the signal to calibrate the target measurement. To the best of our knowledge, the latter method is not in frequent use in the RCS community. The accuracy of the method is determined using small spheres of different sizes which have a forward RCS that is straightforward to calculate using the Mie series. The method described here is also extended to polarimetric measurements of the forward RCS and hence the possibility to determine the extinction cross section for arbitrarily polarized incident radiation. This is tested using measurements on a small helix coil and comparing with method of moments calculations.
  •  
Skapa referenser, mejla, bekava och länka
  • Resultat 651-660 av 982
Typ av publikation
tidskriftsartikel (430)
konferensbidrag (245)
rapport (191)
doktorsavhandling (33)
bokkapitel (28)
annan publikation (25)
visa fler...
bok (11)
licentiatavhandling (9)
forskningsöversikt (7)
samlingsverk (redaktörskap) (1)
proceedings (redaktörskap) (1)
patent (1)
visa färre...
Typ av innehåll
refereegranskat (628)
övrigt vetenskapligt/konstnärligt (332)
populärvet., debatt m.m. (22)
Författare/redaktör
Gustafsson, Mats (532)
Nordebo, Sven (91)
Gustafsson, Mats, 19 ... (79)
Kristensson, Gerhard (60)
Gustafsson, Mats G. (57)
Sohl, Christian (52)
visa fler...
Blomqvist, Göran (50)
Sjöberg, Daniel (47)
Capek, Miloslav (39)
Larsson, Rolf (33)
Blomqvist, Göran, 19 ... (32)
Jelinek, Lukas (30)
Gudmundsson, Anders (28)
Järlskog, Ida, 1991 (28)
Larsson, Christer (26)
Fryknäs, Mårten (25)
Swietlicki, Erik (23)
Janhäll, Sara, 1965- (22)
Schab, Kurt (22)
Hammerling, Ulf (21)
Nygren, Peter (21)
Jonsson, B. Lars G. (20)
Nilsson, Börje (20)
Dahl, Andreas (19)
Bernland, Anders (19)
Cismasu, Marius (19)
Tayli, Doruk (19)
Ehrenborg, Casimir (19)
Johansson, Christer (18)
Persson, Kristin (16)
Isaksson, Anders (16)
Gustafsson, Anders (16)
Andersson-Sköld, Yvo ... (16)
Inganäs, Olle (13)
Lundgren, Johan (13)
Gustafsson, Stefan (13)
He, Sailing (13)
Pistol, Mats Erik (12)
Hagberg, Mats, 1951 (12)
Gustafsson, Ewa, 195 ... (12)
Andersson, Claes (12)
Ivanenko, Yevhen (12)
Tufvesson, Fredrik (11)
Berggren, Magnus (11)
Karlsson, Anders (11)
Gustafsson, Göran (11)
Gustafsson, Jon-Pett ... (11)
Gustafsson, Thomas (11)
Gustafsson, Jonas (11)
Lundberg, Joacim, 19 ... (11)
visa färre...
Lärosäte
Lunds universitet (430)
Uppsala universitet (172)
VTI - Statens väg- och transportforskningsinstitut (128)
Linnéuniversitetet (79)
Kungliga Tekniska Högskolan (64)
Linköpings universitet (58)
visa fler...
Karolinska Institutet (54)
Chalmers tekniska högskola (53)
Göteborgs universitet (51)
RISE (39)
Stockholms universitet (37)
Umeå universitet (23)
Luleå tekniska universitet (14)
Högskolan Dalarna (10)
Sveriges Lantbruksuniversitet (10)
Jönköping University (7)
Södertörns högskola (7)
Högskolan i Skövde (7)
Örebro universitet (6)
Mälardalens universitet (5)
Naturvårdsverket (5)
Gymnastik- och idrottshögskolan (5)
Högskolan i Halmstad (4)
Karlstads universitet (4)
Högskolan i Gävle (3)
Malmö universitet (3)
Mittuniversitetet (3)
Högskolan i Borås (3)
IVL Svenska Miljöinstitutet (3)
Blekinge Tekniska Högskola (1)
visa färre...
Språk
Engelska (848)
Svenska (122)
Odefinierat språk (9)
Spanska (3)
Forskningsämne (UKÄ/SCB)
Teknik (525)
Naturvetenskap (216)
Medicin och hälsovetenskap (128)
Samhällsvetenskap (47)
Humaniora (25)
Lantbruksvetenskap (16)

År

Kungliga biblioteket hanterar dina personuppgifter i enlighet med EU:s dataskyddsförordning (2018), GDPR. Läs mer om hur det funkar här.
Så här hanterar KB dina uppgifter vid användning av denna tjänst.

 
pil uppåt Stäng

Kopiera och spara länken för att återkomma till aktuell vy