| 1. |
- Andersson, Fredrik, et al.
(author)
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Informell coachning på nätet
- 2011. - 1
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In: Mer om nätbaserad utbildnig. - Lund : Studentlitteratur. - 9789144068060 ; , s. 113-126
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Book chapter (peer-reviewed)
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| 2. |
- Andersson, Fredrik, et al.
(author)
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Informell coachning på nätet
- 2011. - 1
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In: Mer om nätbabaserad utbildning. - Lund : Studentlitteratur. - 9789144068060 ; , s. 113-126
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Book chapter (other academic/artistic)abstract
- I detta kapitel beskriver vi hur instant messaging (IM) kan användas för informell coachning. Kapitlet beskriver resultat från två projekt där äldre studenter på kvällstid "coachar" yngre elever, vilket vi benämner "informell coachning". Vi börjar med att beskriva IM och hur det kan användas i utbildningssammanhang. Därefter beskriver vi hur informell coachning går till, pedagogiska utmaningar, hur coachning kan organiseras och vilka verktyg som kan användas. Avslutningsvis reflekterar vi över hur coachning kan bidra till lärande.
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| 3. |
- Carlsson, Fredrik, et al.
(author)
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Effect of heat on interspecific competition in saprotrophic wood fungi
- 2014
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In: Fungal ecology. - : Elsevier BV. - 1754-5048 .- 1878-0083. ; 11, s. 100-106
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Journal article (peer-reviewed)abstract
- Some boreal wood fungi that are associated with forest fire or open dry habitats have an increased resistance to heat in comparison to species associated with a less specific distribution or species found in mesic forests. We hypothesize that extreme temperature-stress experienced during fires will favor species adapted to heat and, ultimately, the composition of species inhabiting logs in such habitats will change. Competitiveness after temperature stress was examined in three fire-associated species – Dichomitus squalens, Gloeophyllum sepiarium and Phlebiopsis gigantea – and three non fire-associated species – Ischnoderma benzoinum, Phellinus pini and Fomitopsis pinicola. There was a difference between the fire-associated species and the non fire-associated species with respect to competitive strength after heat stress. All fire-associated species had an advantage after heat treatment, colonizing a larger volume of wood than any non-fire-associated competitor. Our findings suggest that increased heat tolerance of mycelia can exert a competitive balance shift after forest fire. It shows that a system governed by forest fire will be dominance controlled under certain conditions. Furthermore, from a management perspective, during a prescribed burning, certain species already present in the ecosystem will be favored if the fire is not allowed to totally consume the substrates.
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| 4. |
- Carlsson, Fredrik, 1974-, et al.
(author)
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Increased heat resistance in mycelia from wood fungi prevalent in forests characterized by fire : a possible adaptation to forest fire.
- 2012
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In: Fungal Biology. - : Elsevier BV. - 1878-6146 .- 1878-6162. ; 116:10, s. 1025-1031
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Journal article (peer-reviewed)abstract
- AbstractForest fire has for a long time been the major stand replacing/modifying disturbance in boreal forests. For organisms to adopt to this phenomenon different strategies for protective measurements has evolved. This study focuses on the organism group of wood fungi, and one of several possibilities for adaptation to forest fire - increased heat resistance in the mycelia. 16 species of wood fungi where selected and sorted a priori according to their prevalence for fire affected substrate. These were isolated and re-inoculated on pine wood before testing. Experiments where done in a series where the mycelia was exposed to 100, 140, 180, 220°C for 5, 10, 15, 20, 15 min. A very clear difference was found, the group containing species with a prevalence for a fire affected substrate had a much higher survival rate over all combinations of time and temperature compared to species with a more general ecology. This data suggests that increased heat resistance in mycelia could be a possible adaptation to forest fire. This in turn has major impacts on the ecology and population dynamics of wood fungi. An increase in temperature could shift the population structure in a log, allowing minor non fruiting mycelia content to expand on the expense of earlier dominant colonizers. Furthermore this study has implications on how to control prescribed restoration burning events. When burning areas where the dead wood content is dominated by early decay stages, loss of species can be avoided by proper management.
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| 5. |
- Carlsson, Fredrik, 1974-
(author)
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Wood Fungi and Forest Fire
- 2014
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Doctoral thesis (other academic/artistic)abstract
- Forest fires have been the major stand-replacing/modifying disturbance in boreal forests. To adapt to fire disturbance, different strategies have evolved. This thesis focuses on wood fungi, and the effect of forest fire on this organism group. In many ways it is a study on adaptation to forest fire, in concurrence with adaptation to dry open habitats. In Paper I we study increased heat resistance in mycelia from species prevalent in fire prone environments. Fungi were cultivated on fresh wood and exposed to different temperatures. Species prevalent in fire affected habitats had a much higher survival rate over all combinations of time and temperature compared to species associated with other environments. Based on this results the competitiveness was tested after temperature stress (paper II), three fire associated species, were tested against three non fire associated species. All fire associated species had a clear advantage after heat treatment, conquering a larger volume of wood than its competitor. In paper III we studied the effect of heat shock on decomposition rate, 18 species was tested. Species were cultivated and monitored for CO2 accumulation for 8 weeks and then heat shocked. All species including non fire associated species seemed to up-regulate decomposition after heat shock, this response was more pronounced in fire associated species. To look at the possible effect of forest fire on population structure (Paper IV), we developed 29 SNP/INDELs for Phlebiopsis. gigantea. We amplified the marker containing fragments in 132 individuals of P. gigantea in 6 populations, 3 which were found in areas affected by forest fire and 3 in unaffected areas. We found no genetic structure in accordance to forest fire. However we detected geographic structure, which stands in contrast to earlier studies. This might be due to the method, using SNP´s and number of individuals in the study. Finally we collected cross-sections of decayed logs to evaluate the number of fungal species domains that are likely to be hit when drilling a saw-dust sample in a log. We used these estimates to simulate how many species that will be found by a certain number of samples. We found that in 99% of the
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| 6. |
- Edman, Viktor, et al.
(author)
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Pedestrian Group Tracking Using the GM-PHD Filter
- 2013
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In: Proceedings of the 21st European Signal Processing Conference.
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Conference paper (other academic/artistic)abstract
- A GM-PHD filter is used for pedestrian tracking in a crowdsurveillance application. The purpose is to keep track of thedifferent groups over time as well as to represent the shape ofthe groups and the number of people within the groups. In-put data to the GM-PHD filter are detections using a state ofthe art algorithm applied to video frames from the PETS 2012benchmark data. In a first step, the detections in the framesare converted from image coordinates to world coordinates.This implies that groups can be defined in physical units interms of distance in meters and speed differences in metersper second. The GM-PHD filter is a Bayesian framework thatdoes not form tracks of individuals. Its output is well suitedfor clustering of individuals into groups. The results demon-strate that the GM-PHD filter has the capability of estimatingthe correct number of groups with an accurate representationof their sizes and shapes.
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| 7. |
- Fu, Siyuan, et al.
(author)
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Generalized lock-in amplifier for precision measurement of high frequency signals
- 2013
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In: Review of Scientific Instruments. - : AIP Publishing. - 1089-7623 .- 0034-6748. ; 84:11
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Journal article (peer-reviewed)abstract
- We herein formulate the concept of a generalized lock-in amplifier for the precision measurement of high frequency signals based on digital cavities. Accurate measurement of signals higher than 200 MHz using the generalized lock-in is demonstrated. The technique is compared with a traditional lock-in and its advantages and limitations are discussed. We also briefly point out how the generalized lock-in can be used for precision measurement of giga-hertz signals by using parallel processing of the digitized signals.
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| 8. |
- Jin, Aohan, et al.
(author)
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High precision measurements using high frequency gigahertz signals
- 2014
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In: Review of Scientific Instruments. - : AIP Publishing. - 1089-7623 .- 0034-6748. ; 85:12
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Journal article (peer-reviewed)abstract
- Generalized lock-in amplifiers use digital cavities with Q-factors as high as 5 × 108 to measure signals with very high precision. In this Note, we show that generalized lock-in amplifiers can be used to analyze microwave (giga-hertz) signals with a precision of few tens of hertz. We propose that the physical changes in the medium of propagation can be measured precisely by the ultra-high precision measurement of the signal. We provide evidence to our proposition by verifying the Newton's law of cooling by measuring the effect of change in temperature on the phase and amplitude of the signals propagating through two calibrated cables. The technique could be used to precisely measure different physical properties of the propagation medium, for example, the change in length, resistance, etc. Real time implementation of the technique can open up new methodologies of in situ virtual metrology in material design.
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