| 11. |
- Athanassiou, N., et al.
(författare)
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Simulation of thermal and mechanical performance of laser cladded disc brake rotors
- 2022
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Ingår i: Proceedings of the Institution of mechanical engineers. Part J, journal of engineering tribology. - London : SAGE Publications Ltd. - 1350-6501 .- 2041-305X. ; 236:1, s. 3-14
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Tidskriftsartikel (refereegranskat)abstract
- Disc brakes wear during braking events and release airborne particulates. These particle emissions are currently one of the highest contributors to non-exhaust particle emissions and introduce health hazards as well as environmental contamination. To reduce this problem, wear and corrosion-resistant disc coatings have been implemented on grey cast iron brake disc rotors by using various deposition techniques such as thermal spraying and overlay welding. High thermal gradients during braking introduce risks of flaking off and cracking of thermally sprayed coatings with adhesive bonding to the substrate. Overlay welding by laser cladding offers metallurgical bonding of the coating to the substrate and other benefits that motivate laser cladding as a candidate for the coating of the grey cast iron brake discs. This study aims to investigate the effect of laser cladding on the thermal and thermo-structural performance of the coated grey cast iron brake discs. Therefore, thermal and thermo-stress analysis with COMSOL Multiphysics 5.6 software is performed on braking events of grey cast iron brake discs as non-coated – reference and laser cladding coated with stainless steel welding consumables. The Results demonstrated that surface temperatures were more localised, overall higher in the laser cladded coating with over three times the stresses attained of reference grey cast iron discs. The output of the simulations has been compared by tests found in the literature. Laser cladding presented higher reliability and braking performance, nonetheless requiring the evaluation of its thermal impact on other system components.
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| 12. |
- Barker, Dean, 1977, et al.
(författare)
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Jacob and Martin: Developing digital technology competence in physical education teacher education
- 2016
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Ingår i: Digital Technologies and Learning in Physical Education. - Abingdon, Oxon ; New York, NY : Routledge, 2016. | : Routledge. - 9781315670164 - 9781138947283 - 9781138947290 ; , s. 231-246
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Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- This chapter provides an illustration of how digital technologies (DTs) are experienced by Physical Education Teacher Education (PETE) students. The illustration is based on the reflections of two students at the University of Gothenburg, Sweden. The students received an assignment that involved demonstrating how a specific DT could be implemented. Three perspectives of the practitioners' experiences are provided. A Deweyan perspective shows how the students and their situations are transformed by DTs. A Foucauldian perspective focuses on the regulating aspects of technology. An applied Information Technology perspective demonstrates how DTs become part of the social practices of physical education. © 2017 Ashley Casey, Victoria A. Goodyear and Kathleen M. Armour. All rights reserved.
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| 13. |
- Björ, Bodil, et al.
(författare)
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Cold health impacts in northern Sweden
- 2016
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Ingår i: International Journal of Circumpolar Health. - : Informa UK Limited. - 1239-9736 .- 2242-3982. ; 75:33200
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Tidskriftsartikel (refereegranskat)
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| 14. |
- Björ, Ove, et al.
(författare)
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Reduced mortality rates in a cohort of long-term underground iron-ore miners
- 2013
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Ingår i: American Journal of Industrial Medicine. - : Wiley. - 0271-3586 .- 1097-0274. ; 56:5, s. 531-540
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Tidskriftsartikel (refereegranskat)abstract
- Background Historically, working in iron-ore mines has been associated with an increased risk of lung cancer and silicosis. However, studies on other causes of mortality are inconsistent and in the case of cancer incidence, sparse. The aim of this study was to examine the association between iron-ore mining, mortality and cancer incidence.Methods A 54-year cohort study on iron-ore miners from mines in northern Sweden was carried out comprising 13,000 workers. Standardized rate ratios were calculated comparing the disease frequency, mortality, and cancer incidence with that of the general population of northern Sweden. Poisson regression was used to evaluate the association between the durations of employment and underground work, and outcome.Results Underground mining was associated with a significant decrease in adjusted mortality rate ratios for cerebrovascular and digestive system diseases, and stroke. For several outcomes, elevated standardized rate ratios were observed among blue-collar workers relative to the reference population. However, only the incidence of lung cancer increased with employment time underground (P<0.001).Conclusions Long-term iron-ore mining underground was associated with lower rates regarding several health outcomes. This is possibly explained by factors related to actual job activities, environmental exposure, or the selection of healthier workers for long-term underground employment.Am. J. Ind. Med. 56:531540, 2013. (c) 2013 Wiley Periodicals, Inc.
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| 15. |
- Burström, Lage, et al.
(författare)
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A follow-up study of welders’ exposure to vibration in a heavy engineering production workshop
- 2010
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Ingår i: Journal of Low Frequency Noise Vibration and Active Control. - : Sage Publications. - 0263-0923 .- 1461-3484 .- 2048-4046. ; 29:1, s. 33-39
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Tidskriftsartikel (refereegranskat)abstract
- Manual work involving vibrating power tools is associated with symptoms that include vascular, neurological and musculoskeletal disorders. This study examines the vibration exposure of welders to determine the change between 1987 and 2008. Vibration measurements on handheld tools were used to evaluate the acceleration and the daily exposure time was determined by subjective rating. From these data, the 8-hour equivalent vibration exposure A(8), has been calculated. During the period, the A(8) decreased from 3.9 m/s2 to 1.9 m/s2. It was concluded that this decrease is the result of fewer vibrating tools and a decrease in daily exposure time. Although the daily vibration exposure has decreased over the study time, for some welders the daily vibration exposure A(8) is still above the action value set by the EU directive on vibration. This means more effort should be spent to decrease vibration exposure.
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| 16. |
- Burström, Lage, et al.
(författare)
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Back and neck pain due to working in a cold environment : a cross-sectional study of male construction workers
- 2013
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Ingår i: International Archives of Occupational and Environmental Health. - : Springer Science and Business Media LLC. - 0340-0131 .- 1432-1246. ; 86:7, s. 809-813
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: To study whether work in a cold environment increased the risk of musculoskeletal symptoms in the neck and low back among construction workers. METHODS: This cross-sectional study is based on a cohort of male workers in the Swedish construction industry that participated in regular health examinations through a nationwide occupational health service. The analysis is based on workers examined from 1971 to 1974, who answered a questionnaire including questions about neck and back pain. The cohort consists of 134,754 male workers, including 16,496 office workers and foremen. The health examinations of the workers were conducted in provinces covering Sweden from the south to the north, and temperature data were collected for the provinces. In the analyses, the results were adjusted for age, BMI and use of nicotine. RESULTS: The prevalence's of neck and low back pain were higher among manual construction workers than among foremen and office workers (24.3 vs. 8.6 % and 16.5 vs. 6.2 %, respectively); the corresponding adjusted ORs for low back and neck pain were 1.59 (95 % CI 1.52-1.66) and 1.39 (95 % CI 1.30-1.49), respectively. Workers in the northern and central provinces had higher ORs for low back and neck pain compared to workers in the southern province. The test for trends showed an increased risk of developing low back and neck pain with decreased outdoor temperature. CONCLUSIONS: Outdoor work in a cold environment may increase the risk of low back and neck pain.
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| 17. |
- Burström, Lage, et al.
(författare)
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Daily text messages used as a method for assessing low back pain among workers
- 2016
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Ingår i: Journal of Clinical Epidemiology. - : Elsevier BV. - 0895-4356 .- 1878-5921. ; :70, s. 45-51
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVES: To evaluate a method for collecting data concerning low back pain (LBP) using daily text messages and to characterize the reported LBP in terms of intensity, variability, and episodes.STUDY DESIGN AND SETTING: We conducted a cohort study of LBP among workers used by a mining company. The participants were asked to answer the question "How much pain have you had in your lower back in the last 24 hours on a scale from 0 to 10, where 0 = no pain and 10 = the worst pain imaginable" once a day for 5 weeks, with this process being repeated 6 months later.RESULTS: A total of 121 workers participated in the first period of data collection, and 108 participated in the second period. The daily response rate was 93% for both periods, and cluster analysis was shown to be a feasible statistical method for clustering LBP into subgroups of low, medium, and high pain. The daily text messages method also worked well for assessing the episodic nature of LBP.CONCLUSION: We have demonstrated a method for repeatedly measuring of LBP using daily text messages. The data permitted clustering into subgroups and could be used to define episodes of LBP.
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| 18. |
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| 19. |
- Burström, Lage, et al.
(författare)
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Musculoskeletal symptoms and exposure to whole-body vibration among open-pit mine workers in the arctic
- 2017
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Ingår i: International Journal of Occupational Medicine and Environmental Health. - : Nofer Institute of Occupational Medicine. - 1232-1087 .- 1896-494X. ; 30:4, s. 553-564
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Tidskriftsartikel (refereegranskat)abstract
- Objectives: This cross-sectional questionnaire study was carried out at 4 open-pit mines in Finland, Norway, Russia and Sweden as part of the MineHealth project. The aim has been to compare the prevalence of musculoskeletal symptoms between drivers of mining vehicles and non-drivers. Material and Methods: The mine workers were asked whether they had suffered from any musculoskeletal symptoms during the previous 12 months in specified body regions, and to grade the severity of these symptoms during the past month. They were also asked about their daily driving of mining vehicles. Results: The questionnaire was completed by 1323 workers (757 vehicle drivers) and the reported prevalence and severity of symptoms were highest for the lower back, followed by pain in the neck, shoulder and upper back. Drivers in the Nordic mines reported fewer symptoms than non-drivers, while for Russian mine workers the results were the opposite of that. The daily driving of mining vehicles had no significant association with the risk of symptoms. Female drivers indicated a higher prevalence of symptoms as compared to male drivers. Conclusions: The study provided only weak support for the hypothesis that drivers of vehicles reported a higher prevalence of musculoskeletal symptoms than non-vehicle drivers. There were marked differences in the prevalence of symptoms among workers in various enterprises, even though the nature of the job tasks was similar.
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| 20. |
- Burström, Lage, et al.
(författare)
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Thermal perception thresholds among workers in a cold climate
- 2017
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Ingår i: International Archives of Occupational and Environmental Health. - : Springer. - 0340-0131 .- 1432-1246. ; 90:7, s. 645-652
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Tidskriftsartikel (refereegranskat)abstract
- PURPOSE: To investigate whether exposure to cold could influence the thermal perception thresholds in a working population.METHODS: This cross-sectional study was comprised of 251 males and females and was carried out at two mines in the northern part of Norway and Sweden. The testing included a baseline questionnaire, a clinical examination and measurements of thermal perception thresholds, on both hands, the index (Digit 2) and little (Digit 5) fingers, for heat and cold.RESULTS: The thermal perception thresholds were affected by age, gender and test site. The thresholds were impaired by experiences of frostbite in the fingers and the use of medication that potentially could affect neurosensory functions. No differences were found between the calculated normative values for these workers and those in other comparative investigations conducted in warmer climates.CONCLUSIONS: The study provided no support for the hypothesis that living and working in cold climate will lead to impaired thermal perception thresholds. Exposure to cold that had caused localized damage in the form of frostbite was shown to lead to impaired thermal perception.
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