| 1. |
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| 2. |
- Ahlberg, Carl, et al.
(författare)
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GIMME - A General Image Multiview Manipulation Engine
- 2011
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Ingår i: Proceedings of the International Conference on ReConFigurable Computing and FPGAs (ReConFig 2011). - Los Alamitos, Calif : IEEE Computer Society. - 9780769545516
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Konferensbidrag (refereegranskat)abstract
- This paper presents GIMME (General Image Multiview Manipulation Engine), a highly flexible reconfigurable stand-alone mobile two-camera vision platform with stereo-vision capability. GIMME relies on reconfigurable hardware (FPGA) to perform application-specific low to medium-level image-processing at video rate. The Qseven-extension enables additional processing power. Thanks to its compact design, low power consumption and standardized interfaces (power and communication), GIMME is an ideal vision platform for autonomous and mobile robot applications.
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| 3. |
- Ahlberg, Carl, et al.
(författare)
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GIMME2 - An embedded system for stereo vision and processing of megapixel images with FPGA-acceleration
- 2015
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Ingår i: 2015 International Conference on ReConFigurable Computing and FPGAs, ReConFig 2015. - 9781467394062
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Konferensbidrag (refereegranskat)abstract
- This paper presents GIMME2, an embedded stereovision system, designed to be compact, power efficient, cost effective, and high performing in the area of image processing. GIMME2 features two 10 megapixel image sensors and a Xilinx Zynq, which combines FPGA-fabric with a dual-core ARM CPU on a single chip. This enables GIMME2 to process video-rate megapixel image streams at real-time, exploiting the benefits of heterogeneous processing.
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| 4. |
- Ahlberg, Carl, et al.
(författare)
-
The Black Pearl: An Autonomous Underwater Vehicle
- 2013
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- The Black Pearl is a custom made autonomous underwater vehicle developed at Mälardalen University, Sweden. It is built in a modular fashion, including its mechanics, electronics and software. After a successful participation at the RoboSub competition in 2012 and winning the prize for best craftsmanship, this year we made minor improvements to the hardware, while the focus of the robot's evolution shifted to the software part. In this paper we give an overview of how the Black Pearl is built, both from the hardware and software point of view.
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| 5. |
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| 6. |
- Ahlberg, Carl, et al.
(författare)
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The genetic algorithm census transform : evaluation of census windows of different size and level of sparseness through hardware in-the-loop training
- 2021
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Ingår i: Journal of Real-Time Image Processing. - : SPRINGER HEIDELBERG. - 1861-8200 .- 1861-8219. ; :3, s. 539-559
-
Tidskriftsartikel (refereegranskat)abstract
- Stereo correspondence is a well-established research topic and has spawned categories of algorithms combining several processing steps and strategies. One core part to stereo correspondence is to determine matching cost between the two images, or patches from the two images. Over the years several different cost metrics have been proposed, one being the Census Transform (CT). The CT is well proven for its robust matching, especially along object boundaries, with respect to outliers and radiometric differences. The CT also comes at a low computational cost and is suitable for hardware implementation. Two key developments to the CT are non-centric and sparse comparison schemas, to increase matching performance and/or save computational resources. Recent CT algorithms share both traits but are handcrafted, bounded with respect to symmetry, edge lengths and defined for a specific window size. To overcome this, a Genetic Algorithm (GA) was applied to the CT, proposing the Genetic Algorithm Census Transform (GACT), to automatically derive comparison schemas from example data. In this paper, FPGA-based hardware acceleration of GACT, has enabled evaluation of census windows of different size and shape, by significantly reducing processing time associated with training. The experiments show that lateral GACT windows produce better matching accuracy and require less resources when compared to square windows.
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| 7. |
- Ahlberg, Carl, et al.
(författare)
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Unbounded Sparse Census Transform using Genetic Algorithm
- 2019
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Ingår i: 2019 IEEE WINTER CONFERENCE ON APPLICATIONS OF COMPUTER VISION (WACV). - : IEEE. - 9781728119755 ; , s. 1616-1625
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Konferensbidrag (refereegranskat)abstract
- The Census Transform (CT) is a well proven method for stereo vision that provides robust matching, with respect to object boundaries, outliers and radiometric distortion, at a low computational cost. Recent CT methods propose patterns for pixel comparison and sparsity, to increase matching accuracy and reduce resource requirements. However, these methods are bounded with respect to symmetry and/or edge length. In this paper, a Genetic algorithm (GA) is applied to find a new and powerful CT method. The proposed method, Genetic Algorithm Census Transform (GACT), is compared with the established CT methods, showing better results for benchmarking datasets. Additional experiments have been performed to study the search space and the correlation between training and evaluation data.
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| 8. |
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| 9. |
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| 10. |
- Ekstrand, Eva-Maria, et al.
(författare)
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Methane potentials of the Swedish pulp and paper industry - A screening of wastewater effluents
- 2013
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Ingår i: Applied Energy. - : Elsevier. - 0306-2619 .- 1872-9118. ; 112, s. 507-517
-
Tidskriftsartikel (refereegranskat)abstract
- With the final aim of reducing the energy consumption and increase the methane production at Swedish pulp and paper mills, the methane potential of 62 wastewater effluents from 10 processes at seven pulp and/or paper mills (A-G) was determined in anaerobic batch digestion assays. This mapping is a first step towards an energy efficient and more sustainable utilization of the effluents by anaerobic digestion, and will be followed up by tests in lab-scale and pilot-scale reactors. Five of the mills produce kraft pulp (KP), one thermo-mechanical pulp (TMP), two chemical thermo-mechanical pulp (CTMP) and two neutral sulfite semi-chemical (NSSC) pulp. Both elementary and total chlorine free (ECF and TCF, respectively) bleaching processes were included. The effluents included material from wood rooms, cooking and oxygen delignification, bleaching (often both acid- and alkali effluents), drying and paper/board machinery as well as total effluents before and after sedimentation. The results from the screening showed a large variation in methane yields (percent of theoretical methane potential assuming 940 NmL CH4 per g TOC) among the effluents. For the KP-mills, methane yields above 50% were obtained for the cooking effluents from mills D and F, paper machine wastewater from mill D, condensate streams from mills B, E and F and the composite pre-sedimentation effluent from mill D. The acidic ECF-effluents were shown to be the most toxic to the AD-flora and also seemed to have a negative effect on the yields of composite effluents downstream while three of the alkaline ECF-bleaching effluents gave positive methane yields. ECF bleaching streams gave higher methane yields when hardwood was processed. All TCF-bleaching effluents at the KP mills gave similar degradation patterns with final yields of 10-15% of the theoretical methane potential for four of the five effluents. The composite effluents from the two NSSC-processes gave methane yields of 60% of the theoretical potential. The TMP mill (A) gave the best average yield with all six effluents ranging 40-65% of the theoretical potential. The three samples from the CTMP process at mill B showed potentials around 40% while three of the six effluents at mill G (CTMP) yielded 45-50%.
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| 11. |
- Ekstrand, Fredrik, et al.
(författare)
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High-speed segmentation-driven high-resolution matching
- 2015
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Ingår i: Proceedings of SPIE - The International Society for Optical Engineering, vol. 9445. - : SPIE. - 9781628415605 ; , s. Article number 94451Y-
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Konferensbidrag (refereegranskat)abstract
- This paper proposes a segmentation-based approach for matching of high-resolution stereo images in real time. The approach employs direct region matching in a raster scan fashion influenced by scanline approaches, but with pixel decoupling. To enable real-time performance it is implemented as a heterogeneous system of an FPGA and a sequential processor. Additionally, the approach is designed for low resource usage in order to qualify as part of unified image processing in an embedded system.
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| 12. |
- Ekstrand, Fredrik, et al.
(författare)
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Resource Limited Hardware-based Stereo Matching for High-Speed Vision System
- 2011
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Ingår i: ICARA 2011 - Proceedings of the 5th International Conference on Automation, Robotics and Applications. - 9781457703287 ; , s. 465-469
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Konferensbidrag (refereegranskat)abstract
- This paper proposes a limited implementation of areabasedstereo matching for minimal resource utilization. It shows that it is possible to achieve an acceptable disparity map without the use of expensive resources. The matching accuracy for the single-row SAD can even outperform that of its full-row counterpart. Additionally, it excels in terms of frame rate and resource utilization, and is highly suitable for real-time stereo-vision systems.
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| 13. |
- Ekstrand, Fredrik, 1974-
(författare)
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Resource Optimized Stereo Matching in Reconfigurable Hardware for Autonomous Systems
- 2011
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- There is a need for compact, high-speed, and low-power vision systems for enabling real-time mobile autonomous applications. The best approach to achieve this is to implement the bulk of the application in hardware. Reconfigurable hardware meet these requirements without the limitation of fixed functionality that accompanies application-specific circuits. Resource constraints of reconfigurable hardware calls for optimized implementations i terms of resource usage with maintained performance. The research group in Robotics at Mälardalen University is moving toward the completion of a reconfigurable hardware-platform for stereo vision, coupled with a compact embedded computer. This system will incorporate hardware-based preprocessing components enabling visual perception for autonomous machines. This thesis covers the reconfigurable hardware section of the vision system concerning the realization of scene depth extraction. It shows the advantages of image preprocessing in hardware and propose a resource optimized approach to stereo matching. The work quantifies the impact of reduced resource utilization and a desire for increased accuracy in disparity estimation. The implemented stereo matching approach performs on par with recent similar implementations in terms of accuracy, but excels in terms of resource utilization and resource sharing, as the external memory requirement is removed for larger images. Future work aims to further include processes for navigation, and structure and object recognition. Furthermore, the system will be adapted to real world scenarios, both indoors and outdoors.
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| 14. |
- Ekstrand, Fredrik, et al.
(författare)
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ROBOTICS FOR SMEs - 3D VISION IN REAL-TIME FOR NAVIGATION AND OBJECT RECOGNITION
- 2008
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Ingår i: 39th International Symposium on Robotics, ISR 2008. ; , s. 70-75
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Konferensbidrag (refereegranskat)abstract
- By utilizing the power of hardware we can make a versatile, real-time system capable of both navigation and object gripping, based on basic feature detectors. By using an FPGA together with two cameras we can remove the need for descriptors for navigation by performing what we call spurious matching and the use of 3D landmarks. The approach bypasses the problem of outliers and reduces the time consuming task of data association, which slows many matching algorithms. We also present an approach to object gripping by taking advantage of the full capability of the feature detector.
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| 15. |
- Ekstrand, Fredrik, et al.
(författare)
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Towards an Embedded Real-Time High Resolution Vision System
- 2014
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Ingår i: ADVANCES IN VISUAL COMPUTING (ISVC 2014), PT II. - : SPRINGER-VERLAG BERLIN. - 9783319143644 ; , s. 541-550
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Konferensbidrag (refereegranskat)abstract
- This paper proposes an approach to image processing for high performance vision systems. Focus is on achieving a scalable method for real-time disparity estimation which can support high resolution images and large disparity ranges. The presented implementation is a non-local matching approach building on the innate qualities of the processing platform which, through utilization of a heterogeneous system, combines low-complexity approaches into performing a high-complexity task. The complementary platform composition allows for the FPGA to reduce the amount of data to the CPU while at the same time promoting the available informational content, thus both reducing the workload as well as raising the level of abstraction. Together with the low resource utilization, this allows for the approach to be designed to support advanced functionality in order to qualify as part of unified image processing in an embedded system.
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| 16. |
- Ekstrand, Fredrik, et al.
(författare)
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Utilization and Performance Considerations in Resource Optimized Stereo Matching for Real-Time Reconfigurable Hardware
- 2012
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Ingår i: VISAPP 2012 - Proceedings of the International Conference on Computer Vision Theory and Application, vol. 2. - 9789898565044 ; , s. 415-418
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- This paper presents a set of approaches for increasing the accuracy of basic area-based stereo matching methods. It is targeting real-time FPGA systems for dense disparity map estimation. The methods are focused on low resource usage and maximized improvement per cost unit to enable the inclusion of an autonomous system in an FPGA. The approach performs on par with other area-matching implementations, but at substantially lower resource usage. Additionally, the solution removes the requirement for external memory for reconfigurable hardware together with the limitation in image size accompanying standard methods. As a fully piped complete on-chip solution, it is highly suitable for real-time stereo-vision systems, with a frame rate over 100 fps for Megapixel images.
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| 17. |
- Forsberg, Håkan, et al.
(författare)
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Early Results and Ideas for Enhancements of the Master of Engineering Programme in Dependable Aerospace Systems
- 2017
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Ingår i: The 6th Development Conference for Swedish Engineering USIU2017.
-
Konferensbidrag (refereegranskat)abstract
- The five-year Master of Engineering Programme in Dependable Aerospace Systems, with dependability as its silver thread, started at Mälardalen University (MDH) in 2015. This paper presents selected ideas behind the creation of the programme, together with some preliminary analysis of current results and suggested enhancements for the programme’s fourth and fifth years.
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| 18. |
- Gasser, Fredrik, et al.
(författare)
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Conceptual and empirical item hierarchies of person-centred outpatient care
- 2024
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Konferensbidrag (populärvet., debatt m.m.)abstract
- Introduction : The Person-Centred Care instrument for outpatient care (PCCoc) is a 36-item patient-reported experience measure with 4 ordered response categories, that aims to capture the degree of perceived person-centred care (PCC) from a patient perspective among persons with long-term conditions. The PCCoc is based on a framework that conceptualises outpatient PCC from lower to higher levels of perceived PCC, from personalization via shared decision-making to empowerment, where 35 of the PCCoc items are a part of the framework´s hierarchy. This study investigates to what extent empirical item responses are consistent with the hierarchical PCCoc conceptual framework among persons with long-term conditions in outpatient care. Methods : PCCoc data (322 responses) from persons with long-term psychiatric, cardiological, rheumatological or neurological conditions were analysed. The Rasch measurement model (RMM) was used to evaluate model fit and the empirical item ordering. Correspondence between the empirical and conceptually expected item hierarchies was assessed graphically and using the polyserial correlation between RMM derived item locations and their a-priori expected rank order. Result : Two items showed clear misfit to the RMM (fit residuals >4.9). The polyserial correlation between empirical item locations and the expected rank order using all 35 PCCoc items was 0.64; after removing the 2 misfitting items it was 0.71. In addition, subtests (i.e., testlets consisting of a combination of all items belonging to the respective hierarchical domain) were created to account for any local dependency. Subtest locations on the hierarchical continuum indicated good correspondence between empirical data and the conceptual hierarchy, when based on 35 as well as 33 items. Both subtests had a polyserial correlation of 0.99 between testlet locations and the expected rank order. Conclusion : The observed correspondence between empirical data and the conceptual framework indicates that the PCCoc reflects the underlying framework, and therefore can be a valuable instrument to support targeted PCC-promoting interventions.
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| 19. |
- Gasser, Fredrik, et al.
(författare)
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Further development and evaluation of a questionnaire targeting person-centred outpatient care for persons with long-term conditions
- 2023
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Ingår i: Journal of Patient-Reported Outcomes. - : Springer International Publishing AG. - 2509-8020. ; 7:1, s. 1-10
-
Tidskriftsartikel (refereegranskat)abstract
- AIM: To further develop the Person-Centred Care instrument for outpatient care (PCCoc), evaluate its user-friendliness and content validity, and to explore its basic psychometric properties in various outpatient settings for adults with long-term conditions. BACKGROUND: Person-centred care (PCC) has been identified as a key factor to provide high-quality care. However, there is still a lack of instruments that are based on a clearly defined framework for PCC for persons with long-term conditions in an outpatient context. The PCCoc is a patient-reported experience measure under development aiming to fill this gap. METHODS: First, the 35-item PCCoc was reviewed and further developed in collaboration with a user-council. Second, the revised 36-item PCCoc was tested among persons receiving outpatient care for various long-term conditions. A total of 179 persons with long-term conditions from four different specialties participated in the study. User-friendliness and content validity were assessed through structured interviews and relevance ratings of each item. Content validity index (CVI) for individual items (I-CVI) and for the overall scale (S-CVI) were calculated, and basic psychometric properties of the PCCoc using classical test theory were explored. RESULTS: It took a median of 8 min for participants to complete the PCCoc. The majority found items easy to understand, response categories distinct and that no important areas were missing. Results from the CVI analyses suggested that participants found the content of the PCCoc relevant (I-CVI range 0.82-1, S-CVI = 0.95). All psychometric properties examined were satisfactory (e.g., item-total correlations, 0.45-0.75; Cronbach's alpha, 0.96; test-retest stability, 0.83). CONCLUSION: The PCCoc was considered user-friendly and relevant by the intended users, and its psychometric properties were satisfactory. This implies that the PCCoc can be a valuable instrument for evaluating and developing PCC in outpatient care for persons with long-term conditions. However, further studies of the PCCoc are needed to establish its measurement properties in various outpatient settings.
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| 20. |
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| 21. |
- Ghaderi, Adnan, et al.
(författare)
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FP-SLIC : A Fully-Pipelined FPGA Implementation of Superpixel ImageSegmentation
- 2022
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Ingår i: Proceedings. ; , s. 109-117
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Konferensbidrag (refereegranskat)abstract
- A superpixel segment is a group of pixels that carry similar information. The Simple Linear Iterative Clustering (SLIC) is a well-known algorithm for generating superpixels that offers a good balance between accuracy and efficiency. Nevertheless, due to its high computational requirements, the algorithm does not meet the demands of real-time embedded applications in terms of speed and resources. This paper proposes a fully-pipelined FPGA architecture of SLIC, dubbed FP-SLIC, that exhibits 1) a simplified and efficient algorithm of reduced computational complexity that facilitates algorithm development for FPGAs, 2) a fully pipelined FPGA design operating at 40MHz with a throughput of one pixel per cycle, and 3) a memory-efficient architecture that eliminates the requirement for external memory. Implementation results achieve 259 fps on the BSDS500 dataset, which is ≈ 8.6× more than the requirement for real-time performance (30 frames per second).
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| 22. |
- Kaderland, Annelie, et al.
(författare)
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Att utveckla förmågor genom att prestera sitt yttersta
- 2017. - 1:1
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Ingår i: Undersöka och utveckla undervisning. - Lund : Studentlitteratur AB. - 9789144114170 ; , s. 101-118
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Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- Elevers förmåga att resonera ska genomsyra alla ämnen i grundskolan. Man kan se förmågan som en demokratisk aspekt i ett flerstämmigt klassrum och som oerhört väsentlig ur ett samhällsperspektiv. Vårt fall visar att elevers förmåga att resonera kan utvecklas på relativt kort tid när lärare samtidigt studerar sin egen praktik. I kapitlet diskuteras fallet ur perspektiv som: bedömning, kommunikation, ämnesdidaktik och skolutveckling.
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| 23. |
- Larsson, Madeleine, et al.
(författare)
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The biomethane potential of chemical thermo-mechanical pulp wastewaters in relation to their chemical composition
- 2015
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- This study evaluates the biomethane potential of composite pulping and bleaching chemical thermo-mechanical pulp (CTMP) wastewaters in relation to their composition of organic compounds, as well as to their sulphur contents. The biomethane potential was determined in batch experiments and the CTMP wastewaters from production of bleached spruce-, birch- and aspen pulp and unbleached spruce pulp were analysed for dissolved lignin, carbohydrates, wood extractives, acetic acid and total sulphur content. The biomethane potential obtained for the wastewaters ranged from 350 to 670 NmL g TOC-1 with the highest yield for wastewater from the production of bleached birch CTMP followed by bleached aspen-, bleached spruce- and unbleached spruce CTMP. The main differences in wastewater composition were related to the raw material used for the pulp production, i.e. softwood vs. hardwood. The compounds mainly promoting the biomethane production were acetic acid, xylose, wood extractives, triglycerides and steryl esters, whereas dissolved lignin, sulphur, arabinose, mannose, lignans and free fatty-/resin acids lowered the potential. However, the individual contribution of each variable was not possible to evaluate due to covariations among them.
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| 24. |
- Lidholm, Jörgen, et al.
(författare)
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Two Camera System for Robot Applications; Navigation
- 2008
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Ingår i: 13th IEEE International Conference on Emerging Technologies and Factory Automation, 2008. (ETFA 2008). - 1424415063 ; , s. 345-352
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Konferensbidrag (refereegranskat)abstract
- Current approaches to feature detection and matchingin images strive to increase the repeatability of the detectorand minimize the degree of outliers in the matching.In this paper we present a conflicting approach; we suggestthat a lower performance feature detector can producea result more than adequate for robot navigation irrespectivelyof the amount of outliers. By using an FPGAtogether with two cameras we can remove the need fordescriptors by performing what we call spurious matchingand the use of 3D landmarks. The approach bypassesthe problem of outliers and reduces the time consumingtask of data association, which slows many matching algorithms.
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| 25. |
- Spampinato, Giacomo, et al.
(författare)
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An Embedded Stereo Vision Module for 6D Pose Estimation and Mapping
- 2011
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Ingår i: Proceedings of the IEEE international conference on Intelligent Robots and Systems IROS2011. - New York : IEEE Press. - 9781612844558 ; , s. 1626-1631
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Konferensbidrag (refereegranskat)abstract
- This paper presents an embedded vision system based on reconfigurable hardware (FPGA) and two CMOS cameras to perform stereo image processing and 3D mapping for autonomous navigation. We propose an EKF based visual SLAM and sparse feature detectors to achieve 6D localization of the vehicle in non flat scenarios. The system can operate regardless of the odometry information from the vehicle since visual odometry is used. As a result, the final system is compact and easy to install and configure.
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| 26. |
- Spampinato, Giacomo, et al.
(författare)
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An embedded stereo vision module for industrial vehicles automation
- 2013
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Ingår i: Proceedings of the IEEE International Conference on Industrial Technology. - : IEEE. - 9781467345699 ; , s. 52-57
-
Konferensbidrag (refereegranskat)abstract
- This paper presents an embedded vision system based on reconfigurable hardware (FPGA) to perform stereo image processing and 3D mapping of sparse features for autonomous navigation and obstacle detection in industrial settings. We propose an EKF based visual SLAM to achieve a 6D localization of the vehicle even in non flat scenarios. The system uses vision as the only source of information. As a consequence, it operates regardless of the odometry from the vehicle since visual odometry is used. © 2013 IEEE.
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| 27. |
- Spampinato, Giacomo, et al.
(författare)
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Navigation in a box : Stereovision for industry automation
- 2010
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Ingår i: Advances in Theory and Applications of Stereo Vision. - : InTech. - 9789533075167
-
Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- The research presented addresses the emerging topic of AGVs (Automated Guided Vehicles) specifically related to industrial sites. The work presented has been carried out in the frame of the MALTA project (Multiple Autonomous forklifts for Loading and Transportation Applications), a joint research project between industry and university, funded by the European Regional Development and Robotdalen, in partnership with theSwedish Knowledge Foundation. The project objective is to create fully autonomous forklift trucks for paper reel handling. The result is expected to be of general benefit for industries that use forklift trucks in their material handling through higher operating efficiency and better flexibility with reduced risk for accidents and handling damages than if only manual forklift trucks are used. A brief overview of the state of the art in AGVs will be reported in order to better understand the new challenges and technologies. Among the emerging technologies used for vehicle automation, vision is one of the most promising in terms of versatility and efficiency, with a high potential to drastically reduce the costs.
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| 28. |
- Spampinato, Giacomo, et al.
(författare)
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Stereo Vision Based Navigation for Automated Vehicles in Industry
- 2009
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Ingår i: 14th IEEE International Conference on emerging Technologies and Factory Automation ETFA 2009. - Mallorca, Spain. - 9781424427284
-
Konferensbidrag (refereegranskat)abstract
- This paper proposes a stereo vision based localization and mapping strategy for vehicular navigation within industrial environments using natural landmarks. The work proposed is strictly related to factory automation, since focus is on industrial vehicle autonomous navigation for material handling, in order to increase the operating efficiency with reduced risk for accidents. The stereovision system, proposed as the main sensor, provides the necessary feedback to navigate and simultaneously calibrate the stereocamera parameters (like the camera separation, focal length, camera placement with respect to the robot, etc.). It uses the natural landmarks already present in the environment without additional infrastructures. Some simulation and experimental results are presented in order to explain the proposed method and current status.
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| 29. |
- Toss, Fredrik, 1984-
(författare)
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Body fat distribution, inflammation and cardiovascular disease
- 2011
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Cardiovascular disease (CVD) is one of the major health issues of our time. The prevalence of CVD is increasing, both in industrialized and in developing countries, and causes suffering and a decreased quality of life for millions of people worldwide. CVD can have multiple etiologies, but the main underlying cause is atherosclerosis, which causes blood clot formation and obstructs vital arteries. Multiple risk factors of atherosclerosis have been identified, and body fatness is one of the most important ones. The main aims of this thesis were to investigate the relation between body fatness and: CVD risk factors (paper I), incident stroke (paper II), and overall mortality (paper III). The results showed that abdominal obesity is strongly associated with both CVD risk factors and stroke incidence (papers I-II). The results also suggested that a substantial part of the association between increased body fat and stroke can be explained by an increase in traditional stroke risk factors associated with increased body fat (paper II). A gynoid fat distribution, with a high share of fat located around the hip, is, on the other hand, associated with lower risk factor levels in both men and women, and with a decreased risk of stroke in women (papers I-II). This illustrates the importance of assessing the overall distribution of body fat rather, than solely focusing on total body fatness. In elderly women, total body fat was found to be associated with increased survival, while abdominal fat moderately increased mortality risk (paper III). Lean mass (fat-free mass) was strongly associated with increased survival among elderly men and women (paper III). Erythrocyte sedimentation rate (ESR) is an indicator of inflammation and, possibly, an indicator of atherosclerotic disease. In paper IV, the relationship between ESR in young adulthood and the later risk of myocardial infarction (MI) was studied. Results showed that higher levels of ESR were associated with a higher MI risk, in a dose-responsive manner, and was independent of other well-established risk factors. In summary, both total and regional fat distribution are associated with CVD risk factors and stroke, but do not seem to correspond to an increase in mortality risk among the elderly. Also, inflammation, detected as an increase in ESR, is associated with long term MI risk in young men.
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