| 1. |
- Nilsson, Mikael, et al.
(författare)
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Learning Based Image Segmentation of Pigs in a Pen
- 2014
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Ingår i: ; , s. 1-4
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Konferensbidrag (refereegranskat)abstract
- As farms are getting bigger with more animals, less manual supervision and attention can be given the animals on both group and individual level. In order not to jeopardize animal welfare, automated supervision is in some way already in use. Function and control of ventilation is already in use in modern pig stables, e.g. by the use of sensors for temperature, relative humidity and malfunction connected to alarm. However, by measuring continuously directly on the pigs, more information and more possibilities to adjust production inputs would be possible. In this work, the focus is on a key image processing algorithm aiding such a continuous system - segmentation of pigs in images from video. The proposed solution utilizes extended state-of-the-art features in combination with a structured prediction framework based on a logistic regression solver using elastic net regularization. Objective results on manually segmented images indicate that the proposed solution, based on learning, performs better than approaches suggested in recent publications addressing pig segmentation in video.
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| 2. |
- Piikki, Kristin, et al.
(författare)
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Digital soil mapping of arable land in Sweden – Validation of performance at multiple scales
- 2019
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Ingår i: Geoderma. - : Elsevier BV. - 0016-7061 .- 1872-6259. ; 352, s. 342-350
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Tidskriftsartikel (refereegranskat)abstract
- In this study, we produced a detailed digital soil map of topsoil texture and soil organic matter (SOM) content for 2.4 million ha of arable land in Sweden (DSMS). Three spatially exhaustive datasets (a laser-scanned digital elevation model, airborne gamma radiation scanning data and a legacy Quaternary deposit map) were calibrated against topsoil texture and SOM content in around 13,500 soil samples, using multivariate adaptive regression splines (MARSplines) modelling. We then deployed the MARSplines models to produce raster maps (50 m x 50 m) of clay, sand and SOM content. The modelling procedure was validated by an independent dataset of about 24,000 samples clustered on 544 farms (with a local sample density of one per 3 ha). The error in clay content was < 8% in 75% of the validation samples, while for sand content and SOM content it was 13% and 2%, respectively. Corresponding values for the farm-average level were 6%, 11% and 2%, respectively. Modelling efficiency values revealed that the clay content map was a considerable improvement over the mean of the reference values at national level, regional level and, in many cases, also farm level. However, SOM content predictions showed little or no improvement over the mean of the reference samples (at any scale), due to poor correlation with the exhaustive predictor variables at all three scales investigated. The DSMS soil geodatabase will continue to be improved and have more layers added, e.g. derived layers calculated from the primary clay, sand and SOM layers by use of pedotransfer functions. Practical use of DSMS is exemplified here in an internet application for deriving prescription files for precision agriculture.
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| 3. |
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| 4. |
- Hosseini, Ahmad, et al.
(författare)
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A holistic optimization framework for forest machine trail network design accounting for multiple objectives and machines
- 2019
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Ingår i: Canadian Journal of Forest Research. - : Canadian Science Publishing. - 0045-5067 .- 1208-6037. ; 49:2, s. 111-120
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Tidskriftsartikel (refereegranskat)abstract
- Ground-based mechanized forestry requires the traversal of terrain by heavy machines. The routes they take are often called machine trails, and are created by removing trees from the trail and placing the logs outside it. Designing an optimal machine trail network is a complex locational problem that requires understanding how forestry machines can operate on the terrain as well as the trade-offs between various economic and ecological aspects. Machine trail designs are currently created manually based on intuitive decisions about the importance, correlations, and effects of many potentially conflicting aspects. Badly designed machine trail networks could result in costly operations and adverse environmental impacts. Therefore, this study was conducted to develop a holistic optimization framework for machine trail network design. Key economic and ecological objectives involved in designing machine trail networks for mechanized cut-to-length operations are presented, along with strategies for simultaneously addressing multiple objectives while accounting for the physical capabilities of forestry machines, the impact of slope, and operating costs. Ways of quantitatively formulating and combining these different aspects are demonstrated, together with examples showing how the optimal network design changes in response to various inputs.
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| 5. |
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| 6. |
- Nilsson, Mikael, et al.
(författare)
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Development of automatic surveillance of animal behaviour and welfare using image analysis and machine learned segmentation technique.
- 2015
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Ingår i: Animal. - 1751-7311 .- 1751-732X. ; 9:11, s. 1859-1865
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Tidskriftsartikel (refereegranskat)abstract
- In this paper the feasibility to extract the proportion of pigs located in different areas of a pig pen by advanced image analysis technique is explored and discussed for possible applications. For example, pigs generally locate themselves in the wet dunging area at high ambient temperatures in order to avoid heat stress, as wetting the body surface is the major path to dissipate the heat by evaporation. Thus, the portion of pigs in the dunging area and resting area, respectively, could be used as an indicator of failure of controlling the climate in the pig environment as pigs are not supposed to rest in the dunging area. The computer vision methodology utilizes a learning based segmentation approach using several features extracted from the image. The learning based approach applied is based on extended state-of-the-art features in combination with a structured prediction framework based on a logistic regression solver using elastic net regularization. In addition, the method is able to produce a probability per pixel rather than form a hard decision. This overcomes some of the limitations found in a setup using grey-scale information only. The pig pen is a difficult imaging environment because of challenging lighting conditions like shadows, poor lighting and poor contrast between pig and background. In order to test practical conditions, a pen containing nine young pigs was filmed from a top view perspective by an Axis M3006 camera with a resolution of 640×480 in three, 10-min sessions under different lighting conditions. The results indicate that a learning based method improves, in comparison with greyscale methods, the possibility to reliable identify proportions of pigs in different areas of the pen. Pigs with a changed behaviour (location) in the pen may indicate changed climate conditions. Changed individual behaviour may also indicate inferior health or acute illness.
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| 7. |
- Nordström, Eva-Maria
(författare)
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A Multiple Criteria Approach for Negotiating Ecosystem Services Supply Targets and Forest Owners' Programs
- 2017
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Ingår i: Forest Science. - 0015-749X. ; 63, s. 49-61
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Tidskriftsartikel (refereegranskat)abstract
- Land tenure heterogeneity may be an obstacle to forested landscape-level management planning and the provision of ecosystem services. This research focused on the potential of combining participatory workshops and multiple criteria decision methods (MCDMs) to support the development and negotiation of targets for the supply of ecosystem services and help design the management plan needed to meet those targets. We describe an application to two forested landscapes with several ownership types in Portugal. The approach encompassed the design of two workshops involving more than 40 stakeholders (forests owners, the forest service, the forest industry, local municipalities and other nongovernmental organizations). The list of ecosystem services included carbon stocks, cork, pine cones, and forest inventory at the end of the planning horizon as well as volume flows from a range of forest species. Results demonstrated the potential of MOM tools to help individual forest stakeholders set and adjust ecosystem services target levels. They further demonstrated the potential of MCDMs to facilitate the negotiation of these targets by the stakeholders and the reaching of meaningful solutions. Finally, they demonstrated that these tools provide valuable information to combine the negotiations of both targets and behaviors and programs needed to attain them.
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| 8. |
- Schnitzer, Barbara Maria, 1992, et al.
(författare)
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The synergy of damage repair and retention promotes rejuvenation and prolongs healthy lifespans in cell lineages
- 2020
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Ingår i: PLoS Computational Biology. - : Public Library of Science (PLoS). - 1553-734X .- 1553-7358. ; 16:10
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Tidskriftsartikel (refereegranskat)abstract
- Damaged proteins are inherited asymmetrically during cell division in the yeast Saccharomyces cerevisiae, such that most damage is retained within the mother cell. The consequence is an ageing mother and a rejuvenated daughter cell with full replicative potential. Daughters of old and damaged mothers are however born with increasing levels of damage resulting in lowered replicative lifespans. Remarkably, these prematurely old daughters can give rise to rejuvenated cells with low damage levels and recovered lifespans, called second-degree rejuvenation. We aimed to investigate how damage repair and retention together can promote rejuvenation and at the same time ensure low damage levels in mother cells, reflected in longer health spans. We developed a dynamic model for damage accumulation over successive divisions in individual cells as part of a dynamically growing cell lineage. With detailed knowledge about single-cell dynamics and relationships between all cells in the lineage, we can infer how individual damage repair and retention strategies affect the propagation of damage in the population. We show that damage retention lowers damage levels in the population by reducing the variability across the lineage, and results in larger population sizes. Repairing damage efficiently in early life, as opposed to investing in repair when damage has already accumulated, counteracts accelerated ageing caused by damage retention. It prolongs the health span of individual cells which are moreover less prone to stress. In combination, damage retention and early investment in repair are beneficial for healthy ageing in yeast cell populations.
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| 9. |
- Öhman, Karin, et al.
(författare)
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Using uncertain preferential information from stakeholders to assess the acceptability of alternative forest management plans
- 2018
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Ingår i: Journal of Multi-Criteria Decision Analysis. - : Wiley. - 1057-9214. ; 25, s. 43-52
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Tidskriftsartikel (refereegranskat)abstract
- In forest management planning, participatory planning processes are often encouraged as a means to acquire relevant information and to enhance the stakeholders' acceptability of alternative plans. This requires the aggregation of the stakeholders' preferences that can be done in a wide variety of manners. The aggregation process strives to reduce the information into a single set of preferences that simplifies the information and allows for the use of discrete decision support tools. Depending on how the preferences are aggregated, a wide range of plan rankings can emerge. Although this range of ranking complicates the issue of plan selection, it does highlight the uncertainty involved in aggregating stakeholder preferences. In this study, we suggest an alternative method of deriving rankings for a set of alternative management options. Our proposed method suggests treating acquired preferences as the uncertain elements of a stochastic programming problem and the results provide the decision maker with the acceptability probability for each plan. The method is illustrated with a case of pairwise comparisons from a set of stakeholders representing preferences from different interest groups in a community planning process.
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