| 1. |
- Andersson, Karin, et al.
(författare)
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Ammonia emissions from untreated, separated and digested cattle slurry-Effects of slurry type and application strategy on a Swedish clay soil
- 2023
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Ingår i: Biosystems Engineering. - : Elsevier BV. - 1537-5110 .- 1537-5129. ; 226, s. 194-208
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Tidskriftsartikel (refereegranskat)abstract
- Animal slurry contains plant nutrients such as nitrogen (N) that are essential for crop production. Inorganic slurry N is easily volatilised as ammonia after field application, reducing slurry fertiliser value and causing environmental problems. Ammonia emissions can be reduced by lowering slurry pH, rapid infiltration or incorporation of slurry into soil. This study investigated the effect of different combinations of slurry types and application strategies on ammonia emissions. The slurry types tested were untreated cattle slurry (CS), the liquid fraction from mechanical solid-liquid separation of cattle slurry (LF) and biogas digestate based mainly on cattle slurry (BD). The application strategies tested were trailing hoses, trailing shoes, trailing hose application of acidified slurry and slurry injection. Ammonia emissions after slurry application were measured using wind tunnels, with continuous measurements of ammonia concentrations in outgoing air. Comparisons were also made between measured ammonia emissions and emissions predicted by the ALFAM2 model. Cumulative ammonia emissions after 70 h from LF, CS and BD represented 23%, 29% and 32% of total ammoniacal nitrogen (TAN) applied. Trailing shoes and 50 mm deep injection slots reduced ammonia emissions by on average 17% and 37%, respectively, compared with trailing hoses. Slurry acidification resulted in an average reduction in ammonia emissions of 83%. The ALFAM2 model was reasonably accurate in predicting cumulative emissions (70 h). Accuracy in predicting emission dynamics was low in some cases, likely due to differences between wind tunnel measurements and open-air emis-sions and to model error.(c) 2023 The Authors. Published by Elsevier Ltd on behalf of IAgrE. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).
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| 2. |
- Andersson, Karin, et al.
(författare)
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Effect of exposed surface area on ammonia emissions from untreated, separated, and digested cattle manure
- 2021
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Ingår i: Biosystems Engineering. - : Elsevier BV. - 1537-5110 .- 1537-5129. ; 202, s. 66-78
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Tidskriftsartikel (refereegranskat)abstract
- Ammonia (NH3) emissions from land-applied liquid manure (slurry) contribute to nitrogen deposition, acidification, and formation of fine particles in the atmosphere. Optimal management and field application techniques can reduce emission. A reduction in contact area between the slurry and the atmosphere is expected to reduce NH3 emission. The objectives of this study were to develop a method for quantifying the exposed surface area (ESA) of field-applied slurry over time, and determine the degree to which ESA explains differences in NH3 emission. Two experiments were conducted in which untreated, separated, and digested slurry was applied in bands on two different soils with spring oats stubble. Emission data were obtained from online wind tunnel measurements and slurry characteristics such as surface pH, viscosity, and particle size distribution were measured. The new ESA method relies on fluorescent dye added to the slurry prior to field application, followed by imaging. The results show that the ESA measurements can give new insight into the soil-slurry interactions after manure application, and this may help explain why some types of slurry and application techniques lead to successful abatement under some circumstances, but not under others. Furthermore, a pH-, TAN-, temperature-, and ESA normalised NH3 emission were estimated, helping idetify the effects of infiltration. (c) 2020 IAgrE. Published by Elsevier Ltd. All rights reserved.
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| 3. |
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| 4. |
- Delin, Mattias, et al.
(författare)
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Ascending evacuation - Walking speed in stairs as a function of height
- 2015
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Ingår i: Human Behaviour in fire : 6th International Symposium - 6th International Symposium. - 9780993393303 ; , s. 155-160
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Konferensbidrag (refereegranskat)abstract
- During ascending evacuation in long stairs, there is reason to believe that factors such as fatigue, and change in human behaviour will influence the possibility of satisfactory evacuation and affect the ascending walking speed. Based on these assumption, a 2-year research project was initiated at Lund University. This paper gives a brief description of the project and highlight some initial findings according ascending walking speed and effects of fatigue.
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| 5. |
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| 6. |
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| 7. |
- Högfeldt, Anna-Karin, et al.
(författare)
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Pedagogisk meritering på KTH - Samarbete, excellens och utbildningsinnovation
- 2019
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Ingår i: Bidrag från 7:e Utvecklingskonferensen för Sveriges ingenjörsutbildningar. - Luleå : Luleå University of Technology. ; , s. 76-81
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Konferensbidrag (refereegranskat)abstract
- Detta bidrag beskriver och analyserar förberedelsefasen inför implementeringen av ett högskolepedagogiskt excellensprogram vid Kungliga Tekniska Högskolan, KTH. Programmet syftar till att ytterligare stärka värdet av pedagogiska meriter och samtidigt bidra till lärosätets fortsatta och fördjupade utveckling av utbildningarna och organisationen. De tydligaste riskerna som har identifierats med befintliga pedagogiska meriteringsmodeller är att de kan skapa ett A- och B-lag (mellan en karriär som forskare och en karriär som lärare). Dessutom är det ofta oklart hur personer som har utnämnts till excellenta lärare ska kunna bidra till organisationens och utbildningens utveckling ur ett kortsiktigt såväl som ett långsiktigt perspektiv. En tydlig svaghet med befintliga pedagogiska meriteringsmodeller är att de inte explicit nog ger emfas till aktivt och relevant utvecklingsarbete, utan fokuserar på egenhändigt skrivna pedagogiska portföljer som sällan är framtidsinriktade. KTH:s högskolepedagogiska excellensprogram siktar på att försöka möta dessa risker och svagheter. KTH har, alltjämt sedan det nationella obligatoriet om 15 hp Högskolepedagogik infördes, kvarhållit detta obligatorium. Stora satsningar har gjorts på den högskolepedagogiska verksamheten. Ett gediget utbud av fortbildningsmöjligheter samt arenor för nätverkande har utvecklats. Samtidigt råder svagheter i systemet gällande prövande och tillvaratagande av pedagogisk skicklighet, och det är tydligt att KTH behöver ytterligare utveckling i området. Författarna menar också att i och med att de utmaningar vi står inför gällande pedagogisk meritering ser relativt lika ut vid landets lärosäten, bör ett stärkt nationellt samarbete och nätverkande inom landets ingenjörsutbildningar främjas inom området. Artikelförfattarna representerar KTH:s övergripande ledning, utbildningsledning samt ledningen för den högskolepedagogiska verksamheten.
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| 8. |
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| 9. |
- Norén, Johan, et al.
(författare)
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Ascending Stair Evacuation – effects of fatigue, walking speed & human behaviour
- 2015
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Ingår i: Human Behaviour in fire : 6th International Symposium - 6th International Symposium. - 9780993393303 ; , s. 161-172
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Konferensbidrag (refereegranskat)abstract
- Field study of evacuation upwards long stairs, ascending evacuation, in two different buildings, 48 meters and 109 meters high. Measuring walking speed along the stair slope and vertical speed. Presenting values for different percentiles of the studied population. The importance of not using the same value for walking speed for different stairs since the design of the stairs has a strong impact, and that the vertical speed ought to be considered as well.
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| 10. |
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