| 1. |
- Asplund, Maria. E., 1970, et al.
(author)
-
Dynamics and fate of blue carbon in a mangrove-seagrass seascape : influence of landscape configuration and land-use change
- 2021
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In: Landscape Ecology. - : Springer. - 0921-2973 .- 1572-9761. ; 36, s. 1489-1509
-
Journal article (peer-reviewed)abstract
- Context Seagrass meadows act as efficient natural carbon sinks by sequestering atmospheric CO2 and through trapping of allochthonous organic material, thereby preserving organic carbon (C-org) in their sediments. Less understood is the influence of landscape configuration and transformation (land-use change) on carbon sequestration dynamics in coastal seascapes across the land-sea interface. Objectives We explored the influence of landscape configuration and degradation of adjacent mangroves on the dynamics and fate of C-org in seagrass habitats. Methods Through predictive modelling, we assessed sedimentary C-org content, stocks and source composition in multiple seascapes (km-wide buffer zones) dominated by different seagrass communities in northwest Madagascar. The study area encompassed seagrass meadows adjacent to intact and deforested mangroves. Results The sedimentary C-org content was influenced by a combination of landscape metrics and inherent habitat plant- and sediment-properties. We found a strong land-to-sea gradient, likely driven by hydrodynamic forces, generating distinct patterns in sedimentary C-org levels in seagrass seascapes. There was higher C-org content and a mangrove signal in seagrass surface sediments closer to the deforested mangrove area, possibly due to an escalated export of C-org from deforested mangrove soils. Seascapes comprising large continuous seagrass meadows had higher sedimentary C-org levels in comparison to more diverse and patchy seascapes. Conclusion Our results emphasize the benefit to consider the influence of seascape configuration and connectivity to accurately assess C-org content in coastal habitats. Understanding spatial patterns of variability and what is driving the observed patterns is useful for identifying carbon sink hotspots and develop management prioritizations.
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| 2. |
- Asplund, Maria. E., 1970, et al.
(author)
-
Methane Emissions From Nordic Seagrass Meadow Sediments
- 2022
-
In: Frontiers in Marine Science. - : Frontiers Media S.A.. - 2296-7745. ; 8
-
Journal article (peer-reviewed)abstract
- Shallow coastal soft bottoms are important carbon sinks. Submerged vegetation has been shown to sequester carbon, increase sedimentary organic carbon (C-org) and thus suppress greenhouse gas (GHG) emissions. The ongoing regression of seagrass cover in many areas of the world can therefore lead to accelerated emission of GHGs. In Nordic waters, seagrass meadows have a high capacity for carbon storage, with some areas being recognized as blue carbon hotspots. To what extent these carbon stocks lead to emission of methane (CH4) is not yet known. We investigated benthic CH4 emission (i.e., net release from the sediment) in relation to seagrass (i.e. Zostera marina) cover and sedimentary C-org content (%) during the warm summer period (when emissions are likely to be highest). Methane exchange was measured in situ with benthic chambers at nine sites distributed in three regions along a salinity gradient from similar to 6 in the Baltic Sea (Finland) to similar to 20 in Kattegat (Denmark) and similar to 26 in Skagerrak (Sweden). The net release of CH4 from seagrass sediments and adjacent unvegetated areas was generally low compared to other coastal habitats in the region (such as mussel banks and wetlands) and to other seagrass areas worldwide. The lowest net release was found in Finland. We found a positive relationship between CH4 net release and sedimentary C-org content in both seagrass meadows and unvegetated areas, whereas no clear relationship between seagrass cover and CH4 net release was observed. Overall, the data suggest that Nordic Zostera marina meadows release average levels of CH4 ranging from 0.3 to 3.0 mu g CH4 m(-2) h(-1), which is at least 12-78 times lower (CO2 equivalents) than their carbon accumulation rates previously estimated from seagrass meadows in the region, thereby not hampering their role as carbon sinks. Thus, the relatively weak CH4 emissions from Nordic Z. marina meadows will not outweigh their importance as carbon sinks under present environmental conditions.
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| 3. |
- Dahl, Martin, 1984-, et al.
(author)
-
A 2,000-Year Record of Eelgrass (Zostera marina L.) : Colonization Shows Substantial Gains in Blue Carbon Storage and Nutrient Retention
- 2024
-
In: Global Biogeochemical Cycles. - : John Wiley & Sons. - 0886-6236 .- 1944-9224. ; 38:3
-
Journal article (peer-reviewed)abstract
- Assessing historical environmental conditions linked to habitat colonization is important for understanding long-term resilience and improving conservation and restoration efforts. Such information is lacking for the seagrass Zostera marina, an important foundation species across cold-temperate coastal areas of the Northern Hemisphere. Here, we reconstructed environmental conditions during the last 14,000 years from sediment cores in two eelgrass (Z. marina) meadows along the Swedish west coast, with the main aims to identify the time frame of seagrass colonization and describe subsequent biogeochemical changes following establishment. Based on vegetation proxies (lipid biomarkers), eelgrass colonization occurred about 2,000 years ago after geomorphological changes that resulted in a shallow, sheltered environment favoring seagrass growth. Seagrass establishment led to up to 20- and 24-fold increases in sedimentary carbon and nitrogen accumulation rates, respectively. This demonstrates the capacity of seagrasses as efficient ecosystem engineers and their role in global change mitigation and adaptation through CO2 removal, and nutrient and sediment retention. By combining regional climate projections and landscape models, we assessed potential climate change effects on seagrass growth, productivity and distribution until 2100. These predictions showed that seagrass meadows are mostly at risk from increased sedimentation and hydrodynamic changes, while the impact from sea level rise alone might be of less importance in the studied area. This study showcases the positive feedback between seagrass colonization and environmental conditions, which holds promise for successful conservation and restoration efforts aimed at supporting climate change mitigation and adaptation, and the provision of several other crucial ecosystem services. © 2024. The Authors.
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| 4. |
- Dahl, Martin, 1984-, et al.
(author)
-
First assessment of seagrass carbon accumulation rates in Sweden: A field study from a fjord system at the Skagerrak coast
- 2023
-
In: PLoS Climate. - : Public Library of Science (PLoS). - 2767-3200. ; 2:1
-
Journal article (peer-reviewed)abstract
- Seagrass meadows are globally important blue carbon sinks. In northern cold-temperate regions, eelgrass (Zostera marina) is the dominant seagrass species, and although their sedimentary carbon stocks have been quantified across regions, information regarding the CO2 withdrawal capacity as carbon sinks remains scarce. Here we assessed the carbon (Corg) accumulation rates (CARs) and stocks as well as the organic matter sources in five seagrass meadows in the Gullmar Fjord area on the Swedish Skagerrak coast. We found that the mean (±SD) CAR was 14 ± 3 g Corg m-2 yr-1 over the last ~120–140 years (corresponding to a yearly uptake of 52.4 ± 12.6 g CO2 m-2). The carbon sink capacity is in line with other Z. marina areas but relatively low compared to other seagrass species and regions globally. About half of the sedimentary carbon accumulation (7.1 ± 3.3 g Corg m-2 yr-1) originated from macroalgae biomass, which highlights the importance of non-seagrass derived material for the carbon sink function of seagrass meadows in the area. The Corg stocks were similar among sites when comparing at a standardized depth of 50 cm (4.6–5.9 kg Corg m-2), but showed large variation when assessed for the total extent of the cores (ranging from 0.7 to 20.6 kg Corg m-2 for sediment depths of 11 to at least 149 cm). The low sediment accretion rates (1.18–1.86 mm yr-1) and the relatively thick sediment deposits (with a maximum of >150 cm of sediment depth) suggests that the carbon stocks have likely been accumulated for an extended period of time, and that the documented loss of seagrass meadows in the Swedish Skagerrak region and associated erosion of the sediment could potentially have offset centuries of carbon sequestration.
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| 5. |
- Dahl, Martin, et al.
(author)
-
High Seasonal Variability in Sediment Carbon Stocks of Cold-Temperate Seagrass Meadows
- 2020
-
In: Journal of Geophysical Research: Biogeosciences. - 2169-8953 .- 2169-8961. ; 125:1
-
Journal article (peer-reviewed)abstract
- ©2020. American Geophysical Union. All Rights Reserved. Seagrass meadows have a high ability to capture and store atmospheric CO2 in the plant biomass and underlying sediment and thereby function as efficient carbon sinks. The seagrass Zostera marina is a common species in the temperate Northern Hemisphere, a region with strong seasonal variations in climate. How seasonality affects carbon storage capacity in seagrass meadows is largely unknown, and therefore, in this study, we aimed to assess variations in sedimentary total organic carbon (TOC) content over a 1-year cycle in seagrass meadows on the Swedish west coast. The TOC was measured in two Z. marina sites, one wave exposed and one sheltered, and at two depths (1.5 and 4 m) within each site, every second month from August 2015 to June 2016. We found a strong seasonal variation in carbon density, with a peak in early summer (June), and that the TOC was negatively correlated to the net community production of the meadows, presumably related to organic matter degradation. There was seasonal variation in TOC content at all sediment sections, indicating that the carbon content down to 30 cm is unstable on a seasonal scale and therefore likely not a long-term carbon sink. The yearly mean carbon stocks were substantially higher in the sheltered meadow (3,965 and 3,465 g m−2) compared to the exposed one (2,712 and 1,054 g m−2) with similar seasonal variation. Due to the large intra-annual variability in TOC content, seasonal variation should be considered in carbon stock assessments and management for cold-temperate seagrass meadows.
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| 6. |
- Dahl, Martin, 1984-, et al.
(author)
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Impacts of land-use change and urban development on carbon sequestration in tropical seagrass meadow sediments
- 2022
-
In: Marine Environmental Research. - : Elsevier BV. - 0141-1136 .- 1879-0291. ; 176
-
Journal article (peer-reviewed)abstract
- Seagrass meadows store significant carbon stocks at a global scale, but land-use change and other anthropogenic activities can alter the natural process of organic carbon (Corg) accumulation. Here, we assessed the carbon accumulation history of two seagrass meadows in Zanzibar (Tanzania) that have experienced different degrees of disturbance. The meadow at Stone Town has been highly exposed to urban development during the 20th century, while the Mbweni meadow is located in an area with relatively low impacts but historical clearing of adjacent mangroves. The results showed that the two sites had similar sedimentary Corg accumulation rates (22–25 g m−2 yr−1) since the 1940s, while during the last two decades (∼1998 until 2018) they exhibited 24–30% higher accumulation of Corg, which was linked to shifts in Corg sources. The increase in the δ13C isotopic signature of sedimentary Corg (towards a higher seagrass contribution) at the Stone Town site since 1998 points to improved seagrass meadow conditions and Corg accumulation capacity of the meadow after the relocation of a major sewage outlet in the mid–1990s. In contrast, the decrease in the δ13C signatures of sedimentary Corg in the Mbweni meadow since the early 2010s was likely linked to increased Corg run-off of mangrove/terrestrial material following mangrove deforestation. This study exemplifies two different pathways by which land-based human activities can alter the carbon storage capacity of seagrass meadows (i.e. sewage waste management and mangrove deforestation) and showcases opportunities for management of vegetated coastal Corg sinks.
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| 7. |
- Dahl, Martin, et al.
(author)
-
Impacts of land-use change and urban development on tropical seagrass carbon sinks
-
Other publication (other academic/artistic)abstract
- Seagrass meadows store significant carbon stocks at a global scale, but land-use change and anthropogenic activities can alter the natural process of organic carbon (Corg) accumulation. Here, we assessed the carbon accumulation history of two seagrass meadows in Zanzibar (Tanzania) that experienced different degrees of disturbance. The meadow at Stone Town has been highly exposed to urban development during the 20th century, while the Mbweni meadow is located in an area with relatively low impacts but historical clearing of adjacent mangroves. The results showed that the two sites had similar sedimentary Corg accumulation rates (22–25 g m-2 yr-1) since the 1940s, while during the last two decades (~1998 until 2018) they exhibited 24–30% higher accumulation of Corg, which was linked to shifts in Corg sources. The increase in the δ13C isotopic signature of sedimentary Corg (towards a higher seagrass contribution) at the Stone Town site since 1998 points to improved seagrass meadow conditions and Corg accumulation capacity of the meadow after the relocation of a major sewage outlet in the mid–1990s. In contrast, the decrease in the δ13C signatures of sediment Corg in the Mbweni meadow since the early 2010s was likely linked to Corg transport from mangrove/terrestrial material run-off following the mangrove deforestation. This study exemplifies two different pathways by which land-based human activities can alter the carbon storage capacity of seagrass meadows (i.e. sewage waste management and mangrove deforestation) and showcases opportunities for management of vegetated coastal Corg sinks
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| 8. |
- Dahl, Martin, et al.
(author)
-
Sediment Properties as Important Predictors of Carbon Storage in Zostera marina Meadows : A Comparison of Four European Areas
- 2016
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In: PLOS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 11:12
-
Journal article (peer-reviewed)abstract
- Seagrass ecosystems are important natural carbon sinks but their efficiency varies greatly depending on species composition and environmental conditions. What causes this variation is not fully known and could have important implications for management and protection of the seagrass habitat to continue to act as a natural carbon sink. Here, we assessed sedimentary organic carbon in Zostera marina meadows (and adjacent unvegetated sediment) in four distinct areas of Europe (Gullmar Fjord on the Swedish Skagerrak coast, Asko in the Baltic Sea, Sozopol in the Black Sea and Ria Formosa in southern Portugal) down to similar to 35 cm depth. We also tested how sedimentary organic carbon in Z. marina meadows relates to different sediment characteristics, a range of seagrass-associated variables and water depth. The seagrass carbon storage varied greatly among areas, with an average organic carbon content ranging from 2.79 +/- 0.50% in the Gullmar Fjord to 0.17 +/- 0.02% in the area of Sozopol. We found that a high proportion of fine grain size, high porosity and low density of the sediment is strongly related to high carbon content in Z. marina sediment. We suggest that sediment properties should be included as an important factor when evaluating high priority areas in management of Z. marina generated carbon sinks.
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| 9. |
- Dahl, Martin, et al.
(author)
-
The influence of hydrodynamic exposure on carbon storage and nutrient retention in eelgrass (Zostera marina L.) meadows on the Swedish Skagerrak coast
- 2020
-
In: Scientific Reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 10:1
-
Journal article (peer-reviewed)abstract
- Cold-temperate seagrass (Zostera marina) meadows provide several important ecosystem services, including trapping and storage of sedimentary organic carbon and nutrients. However, seagrass meadows are rapidly decreasing worldwide and there is a pressing need for protective management of the meadows and the organic matter sinks they create. Their carbon and nutrient storage potential must be properly evaluated, both at present situation and under future climate change impacts. In this study, we assessed the effect of wave exposure on sedimentary carbon and nitrogen accumulation using existing data from 53 Z. marina meadows at the Swedish west coast. We found that meadows with higher hydrodynamic exposure had larger absolute organic carbon and nitrogen stocks (at 0-25 cm depth). This can be explained by a hydrodynamically induced sediment compaction in more exposed sites, resulting in increased sediment density and higher accumulation (per unit volume) of sedimentary organic carbon and nitrogen. With higher sediment density, the erosion threshold is assumed to increase, and as climate change-induced storms are predicted to be more common, we suggest that wave exposed meadows can be more resilient toward storms and might therefore be even more important as carbon- and nutrient sinks in the future.
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| 10. |
- Deyanova, Diana, et al.
(author)
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Plant- and habitat productivity in a temperate seagrass system
-
Other publication (other academic/artistic)abstract
- Seagrass meadows are highly productive coastal habitats. Yet, little is known about the contribution of seagrass plants to the total seagrass habitat. To clarify the particular role of the seagrass plants for carbon capture in temperate environments, a one-year study was performed in seagrass meadows on the Swedish west coast. We aimed to assess the link between the net primary productivity of seagrass plants per se, the net production of the seagrass community and the net production of the entire system. To be able to predict effects of environmental changes on seagrass productivity, results were related to changes in water temperature, oxygen levels, light conditions and ice cover. Results showed large variations in net plant productivity across seasons, generally following light- and temperature variability, and ranging from very high (20.03 g C m-2 24h-1 ) in the summer to negative rates (-1.60 g C m-2 24h-1 ) in the least productive winter month. The patterns of variability in seagrass productivity were also influenced by depth- and site-specific dynamics in biomass. The high respiration of the benthic community did largely outbalance the productivity of the seagrass plants, probably as an effect of fast turnover rates. This resulted in an overall yearly low positive carbon balance of the entire seagrass system. Overall, the findings show that seagrass plants contribute substantially to the carbon capture in temperate seagrass habitats, but also that the rate of community respiration appears to be highly dependent on the degree of how much detritus material that is retained within the system. Thus, even though these seagrass systems are highly productive and may contain a large carbon stock, seagrass productivity per se seems not to be the most important determining factor for their carbon sink function.
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| 11. |
- Ismail, Rashid O., 1986-, et al.
(author)
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Effects of calcification on air-water CO2 fluxes in tropical seagrass meadows : A mesocosm experiment
- 2023
-
In: Journal of Experimental Marine Biology and Ecology. - : Elsevier BV. - 0022-0981 .- 1879-1697. ; 561
-
Journal article (peer-reviewed)abstract
- Seagrass meadows deliver a range of ecosystem services, where one of the more important is the capacity to store carbon and serve as sinks for atmospheric carbon dioxide. The capacity of seagrass meadows for carbon storage might, however, be modified and complicated by several factors; one important factor is the possible effects of calcification within the meadows. In tropical areas, seagrass meadows can contain high proportions of calcareous organisms, which through their calcification may cause release of CO2. To study this aspect of the CO2 balance within tropical seagrass systems, we investigated the air-water CO2 flux in seagrass mesocosms with different plant community compositions, i.e. mixtures of seagrass and calcifying macroalgae, having similar overall photosynthetic oxygen evolution rates. The measured CO2 fluxes changed both in rate and direction over the day and were significantly related to plant community composition. Downward fluxes of CO2 were found only over vegetation with high proportion of seagrass and in the afternoon, whereas occurrence of calcifying algae appeared to reverse the flow. A partial least squares (PLS) regression model indicated that pH, pCO2 and dissolved inorganic carbon (DIC) were the primary environmental variables predicting the CO2 fluxes. Our findings show that algal calcification might partly counteract the carbon sequestration in seagrass meadows.
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| 12. |
- Ismail, Rashid O., 1986-, et al.
(author)
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Plant productivity, community composition and carbon import are key drivers of air-water CO2 fluxes in a tropical seagrass meadow : implications for blue carbon science
-
Other publication (other academic/artistic)abstract
- Seagrass meadows are considered efficient sinks of Blue Carbon. They capture CO2 by an effective photosynthetic uptake as well as by trapping large amounts of carbon originating from adjacent systems, which in turn can be stored in the sediments. Such import of allochthonous carbon will be partly degraded in the system, increasing the overall community respiration and thus CO2 production and at the same time add to sediment carbon accumulation. Additionally, tropical seagrass meadows can contain a high proportion of calcareous organisms, which (by the pH suppressing the effect of calcification) can further increase the CO2 partial pressure of the seawater if resulting CO2 is not internally used. The scarce literature on actual CO2 fluxes over submerged vegetation in coastal marine areas is reporting partly contrasting data over how coastal areas in general shall be counted in carbon budgets. To better understand the CO2 cycle within a tropical seagrass system, we constructed a simple carbon flux simulation model in which we evaluated the possible fluxes of carbon within the meadow and with regards to the surrounding seascape. We measured air-water CO2 fluxes in seagrass meadows with different plant community compositions (i.e. mixtures of seagrass and calcifying macroalgae) using field measurements, estimated water column productivity, and extracted data for primary productivity, plant composition, and calcification from previous studies in the same area and, traced organic carbon (Corg) sources in seagrass sediment by measuring bulk stable isotope signals of carbon (δ13C) in order to feed the model with the best available data. When needed we supplemented with published data from other regions. The measured fluxes indicated a net efflux of CO2 over the meadows, from sea to air. The fluxes changed both in rate and direction over the day, and were significantly related to plant community composition and environmental conditions, where pH had the strongest influence on CO2 fluxes. Downward fluxes were found only over vegetation in the afternoon. The isotope signals of carbon revealed a strong input of carbon from other habitats. The outcome of the simulation model suggests that highly productive seagrass meadows can generate a net CO2 flux from the water column to the atmosphere since the plants’ demand for CO2 to a large extent is covered by a major internal cycling of CO2, which is from degradation of autochthonous and allochthonous material as well as from CO2 released from calcification. The calculated accumulation3of sedimentary carbon is however larger than the flow to the atmosphere, indicating that these systems can still be carbon sinks.
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| 13. |
- Krause-Jensen, D, et al.
(author)
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Nordic Blue Carbon Ecosystems: Status and Outlook
- 2022
-
In: Frontiers in Marine Science. - : Frontiers Media SA. - 2296-7745. ; 9
-
Research review (peer-reviewed)abstract
- Vegetated coastal and marine habitats in the Nordic region include salt marshes, eelgrass meadows and, in particular, brown macroalgae (kelp forests and rockweed beds). Such habitats contribute to storage of organic carbon (Blue Carbon – BC) and support coastal protection, biodiversity and water quality. Protection and restoration of these habitats therefore have the potential to deliver climate change mitigation and co-benefits. Here we present the existing knowledge on Nordic BC habitats in terms of habitat area, C-stocks and sequestration rates, co-benefits, policies and management status to inspire a coherent Nordic BC roadmap. The area extent of BC habitats in the region is incompletely assessed, but available information sums up to 1,440 km2 salt marshes, 1,861 (potentially 2,735) km2 seagrass meadows, and 16,532 km2 (potentially 130,735 km2, including coarse Greenland estimates) brown macroalgae, yielding a total of 19,833 (potentially 134,910) km2. Saltmarshes and seagrass meadows have experienced major declines over the past century, while macroalgal trends are more diverse. Based on limited salt marsh data, sediment C-stocks average 3,311 g Corg m-2 (top 40-100 cm) and sequestration rates average 142 g Corg m-2 yr-1. Eelgrass C-stocks average 2,414 g Corg m-2 (top 25 cm) and initial data for sequestration rates range 5-33 g Corg m-2, quantified for one Greenland site and one short term restoration. For Nordic brown macroalgae, peer-reviewed estimates of sediment C-stock and sequestration are lacking. Overall, the review reveals substantial Nordic BC-stocks, but highlights that evidence is still insufficient to provide a robust estimate of all Nordic BC-stocks and sequestration rates. Needed are better quantification of habitat area, C-stocks and fluxes, particularly for macroalgae, as well as identification of target areas for BC management. The review also points to directives and regulations protecting Nordic marine vegetation, and local restoration initiatives with potential to increase C-sequestration but underlines that increased coordination at national and Nordic scales and across sectors is needed. We propose a Nordic BC roadmap for science and management to maximize the potential of BC habitats to mitigate climate change and support coastal protection, biodiversity and additional ecosystem functions.
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| 14. |
- Thul, Peter J., et al.
(author)
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A subcellular map of the human proteome
- 2017
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In: Science. - : American Association for the Advancement of Science. - 0036-8075 .- 1095-9203. ; 356:6340
-
Journal article (peer-reviewed)abstract
- Resolving the spatial distribution of the human proteome at a subcellular level can greatly increase our understanding of human biology and disease. Here we present a comprehensive image-based map of subcellular protein distribution, the Cell Atlas, built by integrating transcriptomics and antibody-based immunofluorescence microscopy with validation by mass spectrometry. Mapping the in situ localization of 12,003 human proteins at a single-cell level to 30 subcellular structures enabled the definition of the proteomes of 13 major organelles. Exploration of the proteomes revealed single-cell variations in abundance or spatial distribution and localization of about half of the proteins to multiple compartments. This subcellular map can be used to refine existing protein-protein interaction networks and provides an important resource to deconvolute the highly complex architecture of the human cell.
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| 15. |
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| 16. |
- Andersson, Mathias H, 1976-, et al.
(author)
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Importance of Using Multiple Sampling Methodologies for Estimating of Fish Community Composition in Offshore Wind Power Construction Areas of the Baltic Sea
- 2007
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In: Ambio. - 0044-7447 .- 1654-7209. ; 36:8, s. 634-636
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Journal article (peer-reviewed)abstract
- It is standard procedure that an Environmental Impact Assessment (EIA) is conducted before larger constructions are built. To adequately describe the impact, methods used in an EIA should be carefully adapted considering both the character of the constructions under development and the environment that will be affected. Various sampling techniques are applied to estimate fish abundances and species composition. Methods used, including trawling, seine and gill netting, angling, echo-sound sampling, fishery data, video recordings, dredging, and visual counts using SCUBA, will all give different estimates of fish community composition.
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| 17. |
- Asplund, Fredrik, et al.
(author)
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Qualifying Software Tools, a Systems Approach
- 2012
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In: Computer Safety, Reliability, and Security. - Berlin, Heidelberg : Springer Berlin/Heidelberg. ; , s. 340-351
-
Conference paper (peer-reviewed)abstract
- Modern safety standards designed to ensure safety in embedded system products often take a descriptive approach, focusing on describing appropriate requirements on management, processes, methods and environments during development. While the qualification of software tools has been included in several such standards, how to handle the safety implications of tools integrated into tool chains has been largely ignored. This problem is aggravated by an increase both in automation of tool integration and the size of development environments.In this paper we define nine safety goals for tool chains and suggest a qualification method that takes a systems approach on certifying software tools as parts of tool chains. With this method, software tools are developed and pre-qualified under the assumption that certain properties will be supported by the development environment they are to be deployed in. The proposed method is intended to (1) achieve a stronger focus on the relevant parts of tool chains in regard to safety and (2) separate the extra effort these parts imply from the effort already stipulated by safety standards.
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| 18. |
- Asplund, Fredrik, 1977-, et al.
(author)
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Reinforcing Learning in an Engineering Master’s Degree Program : The Relevance of Research Training
- 2019
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In: International journal of engineering education. - 0949-149X. ; 35:2, s. 598-616
-
Journal article (peer-reviewed)abstract
- Master students at our institute were graduating without acceptable research proficiency. We intervened by shifting our research training from teaching-centred to student-centred, and from research-related subject content to research-related processes. We performed a mixed methods study aimed to confirm there was improved research proficiency without a negative trade-off for our students’ engineering skills. Results indicated improvements to research proficiency, which our students were able to transfer to engineering-related learning activities to increase their ability to achieve engineering synthesis. This outcome was potentially supported by our courses including several perspectives on scientific knowledge production. This implies that research training, rather than having a negative effect on engineering skills, can be helpful in learning diametrically opposing aspects of thinking required by current engineering. As engineering education evolves towards more cross-disciplinary cooperation, this implies the need to pursue the increased opportunities for students to learn about different perspectives on knowledge production.
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| 19. |
- Asplund, Fredrik
(author)
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Risks Related to the Use of Software Tools when Developing Cyber-Physical Systems : A Critical Perspective on the Future of Developing Complex, Safety-Critical Systems
- 2014
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Doctoral thesis (other academic/artistic)abstract
- The increasing complexity and size of modern Cyber-Physical Systems (CPS) has led to a sharp decline in productivity among CPS designers. Requirements on safety aggravate this problem further, both by being difficult to ensure and due to their high importance to the public.Tools, or rather efforts to facilitate the automation of development processes, are a central ingredient in many of the proposed innovations to mitigate this problem. Even though the safety-related implications of introducing automation in development processes have not been extensively studied, it is known that automation has already had a large impact on operational systems. If tools are to play a part in mitigating the increase in safety-critical CPS complexity, then their actual impact on CPS development, and thereby the safety of the corresponding end products, must be sufficiently understood.An survey of relevant research fields, such as system safety, software engineering and tool integration, is provided to facilitate the discussion on safety-related implications of tool usage. Based on the identification of industrial safety standards as an important source of information and considering that the risks posed by separate tools have been given considerable attention in the transportation domain, several high-profile safety standards in this domain have been surveyed. According to the surveyed standards, automation should primarily be evaluated on its reliable execution of separate process steps independent of human operators. Automation that only supports the actions of operators during CPS development is viewed as relatively inconsequential.A conceptual model and a reference model have been created based on the surveyed research fields. The former defines the entities and relationships most relevant to safety-related risks associated with tool usage. The latter describes aspects of tool integration and how these relate to each other. By combining these models, a risk analysis could be performed and properties of tool chains which need to be ensured to mitigate risk identified. Ten such safety-related characteristics of tool chains are described.These safety-related characteristics provide a systematic way to narrow down what to look for with regard to tool usage and risk. The hypothesis that a large set of factors related to tool usage may introduce risk could thus be tested through an empirical study, which identified safety-related weaknesses in support environments tied both to high and low levels of automation. The conclusion is that a broader perspective, which includes more factors related to tool usage than those considered by the surveyed standards, will be needed.Three possible reasons to disregard such a broad perspective have been refuted, namely requirements on development processes enforced by the domain of CPS itself, certain characteristics of safety-critical CPS and the possibility to place trust in a proven, manual development process. After finding no strong reason to keep a narrow perspective on tool usage, arguments are put forward as to why the future evolution of support environments may actually increase the importance of such a broad perspective.Suggestions for how to update the mental models of the surveyed safety standards, and other standards like them, are put forward based on this identified need for a broader perspective.
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| 20. |
- Asplund, Fredrik, et al.
(author)
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Safety-Guided Design through System-Theoretic Process Analysis, Benefits and Difficulties
- 2012
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In: 30th International System Safety Conference Proceedings.
-
Conference paper (peer-reviewed)abstract
- Development environments for embedded systems are moving towards increased automation between Commercial Of The Shelf (COTS) engineering tools. While automation provides new opportunities for e.g. verification, it also to some extent decreases the possibility of identifying and acting on safety issues that arise during development. To investigate the relationship between tool integration and safety we performed a System-Theoretic Process Analysis (STPA) of a tool chain from an industrial case study. This tool chain was then reanalyzed and redesigned twice, in part motivated by identified hazards.This paper presents our experiences from applying STPA to safety-guided design in the context of integrating COTS engineering tools into tool chains. We discuss the benefits of and difficulties with applying STPA. We also suggest improvements that complement STPA with support methods and tools.The primary benefit was the support in categorizing risks and causes. The three difficulties we encountered were identifying context-specific causal factors, defining control structures across several domains (management, user, technical, etc.) and limiting the domains taken into account. The use of STPA during safety-guided design would be facilitated by the use of expert systems and simulation, especially in regard to relating different domains.
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| 21. |
- Asplund, Fredrik, et al.
(author)
-
The Discourse on Tool Integration Beyond Technology, A Literature Survey
- 2015
-
In: Journal of Systems and Software. - : Elsevier. - 0164-1212 .- 1873-1228. ; 106, s. 117-131
-
Journal article (peer-reviewed)abstract
- The tool integration research area emerged in the 1980s. This survey focuses on those strands of tool integration research that discuss issues beyond technology. We reveal a discourse centered around six frequently mentioned non-functional properties. These properties have been discussed in relation to technology and high level issues. However, while technical details have been covered, high level issues and, by extension, the contexts in which tool integration can be found, are treated indifferently. We conclude that this indifference needs to be challenged, and research on a larger set of stakeholders and contexts initiated. An inventory of the use of classification schemes underlines the difficulty of evolving the classical classification scheme published by Wasserman. Two frequently mentioned redefinitions are highlighted to facilitate their wider use. A closer look at the limited number of research methods and the poor attention to research design indicates a need for a changed set of research methods. We propose more critical case studies and method diversification through theory triangulation. Additionally, among disparate discourses we highlight several focusing on standardization which are likely to contain relevant findings. This suggests that open communities employed in the context of (pre-)standardization could be especially important in furthering the targeted discourse.
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| 22. |
- Asplund, Fredrik, et al.
(author)
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The Need for a Confidence View of CPS Support Environments (Fast Abstract)
- 2015
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In: Proceedings of HASE 2015, The 16th IEEE International Symposium on High Assurance Systems Engineering. - : IEEE Computer Society. - 9781479981113 ; , s. 273-274
-
Conference paper (peer-reviewed)abstract
- Multi-View Modelling Integration Frameworks (MVMIFs) may help mitigate complexity associated with the development of CPS, but may also have implications on safety. Safety-related standards do not provide guidance to mitigate this problem. We therefore suggest that MVMIFs are extended with a confidence view to support the creation of an assurance case that covers issues related to risks in the support environment.
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| 23. |
- Asplund, Fredrik, 1977-
(author)
-
Tool Integration and Safety : A Foundation for Analysing the Impact of Tool Integrationon Non-functional Properties
- 2012
-
Licentiate thesis (other academic/artistic)abstract
- The increasing complexity of embedded systems development is becoming difficult to handle with development environments based on disjoint engineering tools. Support for interactions between various engineering tools, especially through automated means, has therefore received an increased amount of attention during the last few years. The subsequent increase in the amount of tool integration is leading to an increased impact of tool integration on non-functional properties of development efforts, development environments and end products. At the same time there is a lack of methods and tools for analysing the relationship between these properties and tool integration. To establish a foundation for analysing this generic relationship, the specific relationship between tool integration and the safety of end products is analysed in this thesis.A survey was conducted to analyze the State of the Art of tool integration as related to safety. This survey specifically identified the lack of an efficient handling of tool integration by modern safety standards as an important concern. In relation to this survey, three theories were identified as of specific importance. These are the school of thought known as Systems Thinking, the Systems-Theoretic Accident Model and Processes (STAMP) causality model and the System-Theoretic Process Analysis (STPA) hazard analysis technique.Building on these theories, this thesis provides original contributions intended to (1) describe concepts and models related to tool integration and safety (the first and second contribution), (2) link tool integration to safety in a way that reduces complexity during analysis (the third contribution) and (3) propose how to interpret and make use of the implications of the presented theories and the first three contributions (the fourth and fifth contribution).• The first contribution is a new conceptual model of a development effort that emphasizes tool integration.• The second contribution is a new reference model for tool integration in highly heterogeneous environments.• The third contribution consists of nine safety-related tool chain properties, i.e. properties of tool chains that could mitigate at least part of the risks introduced by tool integration.• The fourth contribution is a proposition on how to identify safety implications due to a high level of automation of tool integration.• The fifth contribution is a proposition for a new software tool qualification process.
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| 24. |
- Asplund, Fredrik, et al.
(author)
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Tool Integration Beyond Wasserman
- 2011
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In: Advanced Information Systems Engineering Workshops. - Berlin : Springer-Verlag. - 9783642220555 ; , s. 270-281
-
Conference paper (peer-reviewed)abstract
- The typical development environment today consists of many specialized development tools, which are partially integrated, forming a complex tool landscape with partial integration. Traditional approaches for reasoning about tool integration are insufficient to measure the degree of integration and integration optimality in today’s complex tool landscape. This paper presents a reference model that introduces dependencies between, and metrics for, integration aspects to overcome this problem. This model is used to conceive a method for reasoning about tool integration and identify improvements in an industrial case study. Based on this we are able to conclude that our reference model does not detract value from the principles that it is based on, instead it highlights improvements that were not well visible earlier. We conclude the paper by discussing open issues for our reference model, namely if it is suitable to use during the creation of new systems, if the used integration aspects can be subdivided further to support the analysis of secondary issues related to integration, difficulties related to the state dependency between the data and process aspects within the context of developing embedded systems and the analysis of non-functional requirements to support tool integration.
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| 25. |
- Asplund, Fredrik, et al.
(author)
-
Tool Integration, from Tool to Tool Chain with ISO 26262
- 2012
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In: SAE Technical Paper Series. - 400 Commonwealth Drive, Warrendale, PA, United States : SAE International. - 0148-7191.
-
Conference paper (peer-reviewed)abstract
- The use of innovative power sources in future cars has long-ranging implications on vehicle safety. We studied these implications in the context of the guidance on software tool qualification in the then current ISO 26262 draft, when building an urban concept vehicle to participate in the 2011 Shell Eco-Marathon. While the guidance on tool qualification is detailed, the guidance in regard to tools integrated into tool chains is limited. It only points out that the environment that tools execute in needs to be taken into consideration.In this paper we clarify the implications of tool chains on tool qualification in the context of ISO 26262 by focusing on answering two questions; first, are there parts of the development environment related to tool integration that are likely to fall outside of tool qualification efforts as currently defined by ISO 26262; secondly, can we define if, and -if so- how, tool integration is affected by ensuring functional safety.We conclude by identifying two areas related to tool integration that are likely to fall outside the tool qualification efforts (data integrity and process logic) and describing how different constraints imposed by ISO 26262 in relation to tool qualification conflict when tool integration is improved (improvements aimed at supporting completeness, consistency and the safety lifecycle vs. tool qualification cost).We are able to make additional conclusions in relation to the State of the Art discussion on software tool qualification according to ISO 26262. First, reference tool chains and guidelines on which characteristics tool qualification should ensure for tool chains are needed to complement ISO 26262. Secondly, guidance on tool integration can be found in the completeness characteristic, the consistency characteristic and the ISO 26262 safety lifecycle process. Finally, qualification efforts should ideally target tool chains rather than individual tools.
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| 26. |
- Asplund, Henrik, et al.
(author)
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The COST 259 Directional Channel Model-Part II : Macrocells
- 2006
-
In: IEEE Transactions on Wireless Communications. - 1536-1276 .- 1558-2248. ; 5:12, s. 3434-3450
-
Journal article (peer-reviewed)abstract
- This paper describes the attributes of the COST 259 directional channel model that are applicable for use in the design and implementation of macrocellular mobile and portable radio systems and associated technology. Special care has been taken to model all propagation mechanisms that are currently understood to contribute to the characteristics of practical macrocellular channels and confirm that large scale, small scale, anddirectional characteristics of implemented models are realistic through their comparison with available measured data. The model that is described makes full use of previously published work, as well as incorporating some new results. It is considered that its implementation should contribute to a tool that can be used for simulations and comparison of different aspects of a large variety of wireless communication systems, including those that exploit the spatial aspects of radio channels, as, for example, throughthe use of adaptive antenna systems.
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| 27. |
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| 28. |
- Asplund, Isabel, et al.
(author)
-
Samverkan inom socialtjänsten kring våld i nära relationer : Erfarenheter, utmaningar och möjligheter
- 2022
-
Conference paper (pop. science, debate, etc.)abstract
- Panelsamtal om socialtjänstens insatser för att hantera våld i nära relationer, särskilt de olika former av våld som berör barn. Samtalet kommer att kretsa kring frågan om hur ett mer samordnat och barncentrerat system av insatser mot våld kan åstadkommas, ett system där våldsutsatta barn både kan få det skydd och stöd de behöver, och vara delaktiga i alla processer som berör dem. Utgångspunkten är de olika medverkandes erfarenheter av problematiken kring våld, barn och samordning inom socialtjänsten och mellan socialtjänst och andra aktörer. Utifrån dessa erfarenheter reflekterar paneldeltagarna tillsammans reflektera över de utmaningar respektive utvecklingsmöjligheter när det gäller att utveckla mer samordnade interventioner kring våld i nära relationer.Deltar i panelsamtalet gör: Isabel Asplund, projektledare Islandsprojektet Stockholm, Maria Eriksson, professor Marie Cederschiöld högskola, Anna Friberg, biträdande enhetschef i Enheten för stöd och skydd och chef över Barnahus Stockholm, Frida Malm, biträdande enhetschef, Relationsvåldscentrum RVC Innerstad, Liselotte Tronders, biträdande enhetschef Stockholm stads SocialjourPanelsamtalet modereras av Martin Börjeson.
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| 29. |
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| 30. |
- Asplund, Linnea, et al.
(author)
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Functional traits associated with nitrogen use efficiency in wheat
- 2016
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In: Acta Agriculturae Scandinavica, Section B - Soil and Plant Science. - : Informa UK Limited. - 0906-4710 .- 1651-1913. ; 66, s. 153-169
-
Journal article (peer-reviewed)abstract
- The association between functional traits and nitrogen use efficiency (NUE) was investigated to assist the breeding of nitrogen (N) use-efficient bread wheat (Triticum aestivum ssp. aestivum) varieties. This study combined results from a climate chamber experiment involving 41 spring wheat varieties and a field experiment involving six winter and six spring wheat varieties grown with and without the application of mineral N fertiliser. The climate chamber experiment was analysed by partial least squares (PLS) regression, with several predictors and NUE as response, to identify traits related to NUE. Specific hypotheses were then tested in the field experiment. The PLS indicated six traits of particular importance for overall NUE: leaf chlorophyll (SPAD value) of the top leaf at stem elongation, grains ear(-1), ears pot(-1), straw biomass pot(-1), days between emergence and anthesis, and days between emergence and completed senescence. In the field experiment, the SPAD value of flag leaves of winter wheat around anthesis was positively correlated with NUE and total grain N, at both N levels. Fast development was positively correlated with high NUE and N uptake efficiency in spring wheat. Early senescence of the flag leaf was positively correlated with grain N concentration and negatively correlated with grain-specific N efficiency in winter wheat at low N fertilisation levels. The results indicate that high SPAD value of the top leaf might be a candidate trait that could be used in wheat breeding for improved NUE, while genetic variation in senescence could possibly be used to tailor varieties for different end-use quality when grown at low N. More studies are needed to validate these findings in other environments and for other genotypes.
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| 31. |
- Asplund, Linnea, et al.
(author)
-
Proof of concept: Nitrogen use efficiency of contrasting spring wheat varieties grown in greenhouse and field
- 2014
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In: Plant and Soil. - : Springer Science and Business Media LLC. - 0032-079X .- 1573-5036. ; 374, s. 829-842
-
Journal article (peer-reviewed)abstract
- Major aims were to test and evaluate a new concept for assessment of nitrogen use efficiency (NUE) of crops by growing six spring wheat varieties in greenhouse and field environments. NUE was calculated with a plant based concept integrating the entire crop life history and separating plant characteristics from environmental factors affecting NUE. Specific hypotheses were tested related to the varieties' drought and nutrient fertilisation responses for NUE components, and coherence of those responses in field and greenhouse.The wheat (Triticum aestivum L.) cultivated varieties 'Diskett', 'Granary', 'Quarna', 'Stilett', 'Vinjett', and a Swedish landrace ('Dala') were grown in field and greenhouse environments in Central Sweden. Two fertilisation treatments were included in a field and greenhouse experiment, and in the greenhouse also drought. The NUE components N uptake efficiency (U-N), grain-specific N efficiency (E-N,E-g) and grain N concentration (C-N,C-g) were assessed.Drought reduced yield and NUE through E-N,E-g, and more so when drought occurred prior to anthesis than after anthesis. Effect of fertilisation treatment on NUE components was similar in the two set-ups, but there were fewer variety x fertilisation interactions in the field. U-N was higher in the field and E-N,E-g was higher in the greenhouse, while C-N,C-g and overall NUE were similar in the two environments. Ranking of varieties regarding NUE and U-N was similar in the greenhouse and field, but different regarding E-N,E-g and C-N,C-g.The NUE concept is a useful tool to describe and integrate important NUE components for crops grown in different treatments (nutrient fertilisation, drought) and experimental set-ups, i.e. greenhouse and field. Similar variety ranking in overall NUE across experimental set-ups indicates stable results in different environments.
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| 32. |
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| 33. |
- Asplund, Linnea, et al.
(author)
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Swedish Spring Wheat Varieties with the Rare High Grain Protein Allele of NAM-B1 Differ in Leaf Senescence and Grain Mineral Content
- 2013
-
In: PLoS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 8
-
Journal article (peer-reviewed)abstract
- Some Swedish spring wheat varieties have recently been shown to carry a rare wildtype (wt) allele of the gene NAM-B1, known to affect leaf senescence and nutrient retranslocation to the grain. The wt allele is believed to increase grain protein concentration and has attracted interest from breeders since it could contribute to higher grain quality and more nitrogen-efficient varieties. This study investigated whether Swedish varieties with the wt allele differ from varieties with one of the more common, non-functional alleles in order to examine the effect of the gene in a wide genetic background, and possibly explain why the allele has been retained in Swedish varieties. Forty varieties of spring wheat differing in NAM-B1 allele type were cultivated under controlled conditions. Senescence was monitored and grains were harvested and analyzed for mineral nutrient concentration. Varieties with the wt allele reached anthesis earlier and completed senescence faster than varieties with the non-functional allele. The wt varieties also had more ears, lighter grains and higher yields of P and K. Contrary to previous information on effects of the wt allele, our wt varieties did not have increased grain N concentration or grain N yield. In addition, temporal studies showed that straw length has decreased but grain N yield has remained unaffected over a century of Swedish spring wheat breeding. The faster development of wt varieties supports the hypothesis of NAM-B1 being preserved in Fennoscandia, with its short growing season, because of accelerated development conferred by the NAM-B1 wt allele. Although the possible effects of other gene actions were impossible to distinguish, the genetic resource of Fennoscandian spring wheats with the wt NAM-B1 allele is interesting to investigate further for breeding purposes.
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| 34. |
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| 35. |
- Asplund, Martin, et al.
(author)
-
A stellar endgame - The born-again Sakurai's object
- 1997
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In: ASTRONOMY AND ASTROPHYSICS. - : SPRINGER VERLAG. - 0004-6361. ; 321:2, s. L17-L20
-
Journal article (peer-reviewed)abstract
- The surface chemical composition of this remarkable star shows that it is hydrogen-deficient, carbon-rich and enriched in the light s-process elements. Spectra taken in May and October 1996 indicate a decrease in the surface hydrogen abundance by 0.7 dex
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| 36. |
- Asplund, Martin, et al.
(author)
-
Abundance similarities between the R CrB star V854 Cen and the born-again Sakurai's object
- 1998
-
In: ASTRONOMY AND ASTROPHYSICS. - : SPRINGER VERLAG. - 0004-6361. ; 332:2, s. 651-660
-
Journal article (peer-reviewed)abstract
- The elemental abundances of the mildly hydrogen-deficient R Coronae Borealis (R CrB) star V854 Cen have been estimated. The R CrB stars have been divided into majority and minority classes judging by their abundance patterns. Class assignment has previous
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| 37. |
- Asplund, Matthias, et al.
(author)
-
Combating curve squeal noise
- 2016
-
In: Combating curve squeal noise.
-
Conference paper (peer-reviewed)abstract
- Society demand for more sustainable transports is increasing, starting a modal shift from road to railway. The resulting increase in railway traffic intensity is leading to more activities on the track, even during the night time. For many years continuous urbanization has been resulting in a higher density of residents in areas close to railway tracks. The combination of these factors is raising the issue of noise disturbances from railway transports, which is forcing infrastructure managers to take action to combat noise from railway traffic systematically. There are different types of noise emanating from railways and one of the most annoying is curve squeal noise. This paper deals with the curve squeal phenomenon, the places where it occurs, and different methods for reducing it. The curving behaviour of a vehicle plays an important role in the generation of curve squeals, and therefore the way in which different rail profiles affect the capability to steer in a sharp curve is dealt within this paper. The paper is based on two case studies with investigated curves in urban regions that suffer from squeal noise, and in which comparisons between measurements and simulations were performed. The outcome of these studies is a workflow for combating squeal noise, results concerning the effects of a top-of-rail friction modifier on noise mitigation, and a proposed rail profiles for improving the steering capability of vehicles.
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| 38. |
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| 39. |
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| 40. |
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| 41. |
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| 42. |
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| 43. |
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| 44. |
- Asplund, Martin, et al.
(author)
-
Radiative Transfer in 3D Model Stellar Atmospheres
- 2003
-
In: ASP Conference Proceedings. - 1583811400 ; , s. 197-
-
Conference paper (pop. science, debate, etc.)abstract
- Recently 3D hydrodynamical simulations of stellar surface convection have become feasible thanks to advances in computer technology and efficient numerical algorithms. Available observational diagnostics indicate that these models are highly realistic in describing the topology of stellar granulation and for spectral line formation purposes. The traditional free parameters (mixing length parameters, micro- and macroturbulence) always inherent in standard 1D analyses have thus finally become obsolete. These 3D models can therefore both shed light on the elusive nature of stellar convection as well as be employed in element abundance analyses. In the present contribution we will describe some aspects of the models and possible applications of them in terms of radiative transfer.
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| 45. |
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| 46. |
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| 47. |
- Asplund, Martin, et al.
(author)
-
The Chemical Composition of the Sun
- 2009
-
In: Annual Review of Astronomy and Astrophysics. - : Annual Reviews. - 0066-4146 .- 1545-4282. ; 47, s. 481-522
-
Research review (peer-reviewed)abstract
- The solar chemical composition is an important ingredient in our understanding of the formation, structure, and evolution of both the Sun and our Solar System. Furthermore, it is an essential reference standard against which the elemental contents of other astronomical objects are compared. In this review, we evaluate the current understanding of the solar photospheric composition. In particular, we present a redetermination of the abundances of nearly all available elements, using a realistic new three-dimensional (3D), time-dependent hydrodynamical model of the solar atmosphere. We have carefully considered the atomic input data and selection of spectral lines, and accounted for departures from local thermodynamic equilibrium (LTE) whenever possible. The end result is a comprehensive and homogeneous compilation of the solar elemental abundances. Particularly noteworthy findings are significantly lower abundances of C, N, O, and Ne compared to the widely used values of a decade ago. The new solar chemical composition is supported by a high degree of internal consistency between available abundance indicators, and by agreement with values obtained in the Solar Neighborhood and from the most pristine meteorites. There is, however, a stark conflict with standard models of the solar interior according to helio-seismology, a discrepancy that has yet to find a satisfactory resolution.
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| 48. |
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| 49. |
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| 50. |
- Asplund, Simon, et al.
(author)
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SWAY - designing for balance and posture awareness
- 2018
-
In: TEI 2018 - Proceedings of the 12th International Conference on Tangible, Embedded, and Embodied Interaction. - New York : Association for Computing Machinery (ACM). - 9781450355681 ; , s. 470-475
-
Conference paper (peer-reviewed)abstract
- This paper presents the SWAY prototype that encourages people to explore aspects around balance and posture in a playful way. The prototype senses small movements and shifts in posture using a Kinect sensor, and translates these movements to the tilting of a platform holding a set of marbles, and to haptic feedback in the form of vibrations. The prototype provides an interactive experience focusing on building body awareness with a particular focus on balance and posture. The design inquiry provided new insights with respect to reinforcement of bodily experiences and how different modalities affect the guiding of attention.
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