| 3071. |
- Iriondo Pascual, Aitor, 1993-
(författare)
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Simulation-based multi-objective optimization of productivity and worker well-being
- 2023
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- In industry, simulation software is used to simulate production, making it possible to predict events in production, calculate times and plan production, even in the early phases of the production development process. Software known as digital human modelling (DHM) tools can also be used to simulate humans working in production. When simulating digital human models, ergonomics evaluations can be carried out to assess whether workstation designs offer appropriate ergonomic conditions for the workers. However, simulations performed to predict and plan production are usually done separately from the human simulations performed to evaluate ergonomics. This can lead to suboptimal solutions in which a factory is optimized to improve either productivity or ergonomics. This thesis outlines the hypothesis that more optimal solutions for workstation design, layout and line balancing can be obtained in simulations by optimizing productivity and ergonomic factors simultaneously instead of considering them separately. Hence, the aim is to carry out research on the development of a simulation-based multi-objective optimization method for productivity and ergonomic factors and to realize the method as a software tool in order to test and communicate it. From an application and societal-impact perspective, the overall objective is to offer a new approach for designing production systems that focuses on both over-all system performance and the well-being of workers, reduces the effort of engineers and helps industry create more productive and sustainable workspaces.
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| 3072. |
- Iriondo Pascual, Aitor, 1993-, et al.
(författare)
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Using time-based musculoskeletal risk assessment methods to assess worker well-being in optimizations in a welding station design
- 2022
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Ingår i: Proceedings of the 7th International Digital Human Modeling Symposium (DHM 2022), August 29–30, 2022, Iowa City, Iowa, USA. - : University of Iowa Press. - 9780984037841 ; , s. 1-13
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Konferensbidrag (refereegranskat)abstract
- Simulation using virtual models is used widely in industries because it enables efficient creation, testing, and optimization of the design of products and production systems in virtual worlds. Simulation is also used in the design of workstations to assess worker well-being by using digital human modeling (DHM) tools. DHM tools typically include musculoskeletal risk assessment methods, such as RULA, REBA, OWAS, and NIOSH Lifting Equation, that can be used to study, analyze, and evaluate the risk of work-related musculoskeletal disorders of different design solutions in a proactive manner. However, most musculoskeletal risk assessment methods implemented in DHM tools are in essence made to assess static instances only. Also, the methods are typically made to support manual observations of the work rather than by algorithms in a software. This means that, when simulating full work sequences to evaluate manikins’ well-being, using these methods become problematic in terms of the legitimacy of the evaluation results. In addition to that, to consider objectives in optimizations, they should be measurable with real numbers, which most of musculoskeletal risk assessment methods cannot provide when simulating full work sequences.In this study, we implemented the musculoskeletal risk assessment method OWAS in a digital tool connected to the DHM tool IPS IMMA. We applied the Lundqvist index on top of the OWAS whole body risk category score. This gave us an integer of the time-based ergonomic load for a specific simulation sequence, enabling us to qualitatively compare different design solutions. Using this approach, we performed an optimization in a welding gun workstation to improve the design of the workstation. The results show that using time-based musculoskeletal risk assessment methods as objective functions in optimizations in DHM tools can provide valuable decision support in finding solutions for workstation designs that consider worker well-being.
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| 3073. |
- Irisdotter Aldenmyr, Sara, 1976-, et al.
(författare)
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The inward turn in therapeutic education : an individual enterprise promoted in the name of the common good
- 2016
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Ingår i: Pedagogy, Culture & Society. - : Informa UK Limited. - 1468-1366 .- 1747-5104. ; 24:3, s. 387-400
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Tidskriftsartikel (refereegranskat)abstract
- In this paper, focus rests on the relatively new international phenomenon of therapeutic education. Taking in the fact that this phenomenon is part of the schools’ assigned task to see to the formation of young people, the aim of the paper is twofold: to highlight what rationales that emerge in the formation of young people’s emotions in school, and to discuss these rationales in terms of vital principles of public education for the common good in society. The results are based on an empirical case study of ten Swedish teachers involved in the so-called Life Competence Education, which serves as a contextualisation of this phenomenon. Two rationales of this formation stand out as key; the seriousness of the inward turn of the individual, and the crucial step of sharing one’s innermost. Although these rationales involve collective notions of the students’ emotional well-being, they are quite firmly anchored, we argue, in the single individuals’ well-being.
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| 3074. |
- Irisdotter Aldenmyr, Sara, et al.
(författare)
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Worries and possibilities in active citizenship : Three Swedish educational contexts
- 2012
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Ingår i: Education, Citizenship and Social Justice. - : Sage Publications. - 1746-1979 .- 1746-1987. ; 7:3, s. 255-270
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Tidskriftsartikel (refereegranskat)abstract
- This article examines how the concept of active citizenship has been given a neo-liberal character by examining practice in three different educational contexts in Sweden. The concept of active citizenship has become influential in educational policy and practice throughout the European Union. The aim of this article is to highlight concerns at how this concept has come to be re-shaped by neo-liberal principles in Swedish education. The analysis highlights three themes, based on voice, ethical awareness and complexity and mutuality of lived experience, and argues that they provide the basis for a shift away from the present neo-liberal colouring of the concept.
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| 3075. |
- Isaksson, Anna, 1970-, et al.
(författare)
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Influence of enclosed air on vibration modes of a shell structure
- 1995
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Ingår i: Journal of Sound and Vibration. - : Elsevier BV. - 0022-460X .- 1095-8568. ; 187:3, s. 451-466
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Tidskriftsartikel (refereegranskat)abstract
- Experiments show that enclosed air in a thin walled structure affects some modes of vibration significantly. Air coupling between vibrating sides of the structure cannot (always) be neglected and frequencies cannot be predicted if calculations are performed as if in a vacuum. As a first attempt to include the enclosed air in a FE model of a violin body, the elastic properties of the air are modelled as a set of one dimensional non-interacting elastic members (columns of air) connecting opposite sides of the orthotropic shell structure. This admittedly oversimplified (but easy to formulate) model must be used with great care, since it neglects the three-dimensional wave behaviour of the enclosed air. A lower limit of allowed frequencies is that which corresponds to a wavelength in air which is much greater than a characteristic length of the object. For the violin this lower limit is less than about 600 Hz. Optical modal analysis of the real, physical, violin model has been performed by using electronic holography. Calculated modes of vibration are compared with experimental ones. For the lowest eigenmodes a good agreement between measured and calculated frequencies is reached despite the simple air model used. Modal shapes remain surprisingly unaffected. For some engineering calculations the simple one-dimensional model might be used.
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| 3076. |
- Islam, Khairul, et al.
(författare)
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Dose-response relationship between arsenic exposure and the serum enzymes for liver function tests in the individuals exposed to arsenic : a cross sectional study in Bangladesh
- 2011
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Ingår i: Environmental Health. - : BioMed Central (BMC). - 1476-069X. ; 10
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Tidskriftsartikel (refereegranskat)abstract
- Background: Chronic arsenic exposure has been shown to cause liver damage. However, serum hepatic enzyme activity as recognized on liver function tests (LFTs) showing a dose-response relationship with arsenic exposure has not yet been clearly documented. The aim of our study was to investigate the dose-response relationship between arsenic exposure and major serum enzyme marker activity associated with LFTs in the population living in arsenic-endemic areas in Bangladesh. Methods: A total of 200 residents living in arsenic-endemic areas in Bangladesh were selected as study subjects. Arsenic concentrations in the drinking water, hair and nails were measured by Inductively Coupled Plasma Mass Spectroscopy (ICP-MS). The study subjects were stratified into quartile groups as follows, based on concentrations of arsenic in the drinking water, as well as in subjects' hair and nails: lowest, low, medium and high. The serum hepatic enzyme activities of alkaline phosphatase (ALP), aspartate transaminase (AST) and alanine transaminase (ALT) were then assayed. Results: Arsenic concentrations in the subjects' hair and nails were positively correlated with arsenic levels in the drinking water. As regards the exposure-response relationship with arsenic in the drinking water, the respective activities of ALP, AST and ALT were found to be significantly increased in the high-exposure groups compared to the lowest-exposure groups before and after adjustments were made for different covariates. With internal exposure markers (arsenic in hair and nails), the ALP, AST and ALT activity profiles assumed a similar shape of dose-response relationship, with very few differences seen in the higher groups compared to the lowest group, most likely due to the temporalities of exposure metrics. Conclusions: The present study demonstrated that arsenic concentrations in the drinking water were strongly correlated with arsenic concentrations in the subjects' hair and nails. Further, this study revealed a novel exposure- and dose- response relationship between arsenic exposure metrics and serum hepatic enzyme activity. Elevated serum hepatic enzyme activities in the higher exposure gradients provided new insights into arsenic-induced liver toxicity that might be helpful for the early prognosis of arsenic-induced liver diseases.
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| 3077. |
- Islam, Md Shofikul, et al.
(författare)
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Elevated concentrations of serum matrix metalloproteinase-2 and -9 and their associations with circulating markers of cardiovascular diseases in chronic arsenic-exposed individuals
- 2015
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Ingår i: Environmental Health. - : BioMed Central (BMC). - 1476-069X. ; 14:1
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Tidskriftsartikel (refereegranskat)abstract
- Background: Cardiovascular diseases (CVDs) and cancers are the major causes of chronic arsenic exposure-related morbidity and mortality. Matrix metalloproteinase-2 (MMP-2) and −9 (MMP-9) are deeply involved in the pathogenesis of CVDs and cancers. This study has been designed to evaluate the interactions of arsenic exposure with serum MMP-2 and MMP-9 concentrations especially in relation to the circulating biomarkers of CVDs.Methods: A total of 373 human subjects, 265 from arsenic-endemic and 108 from non-endemic areas in Bangladesh were recruited for this study. Arsenic concentrations in the specimens were measured by inductively coupled plasma mass spectroscopy (ICP-MS) and serum MMPs were quantified by immunoassay kits.Results: Serum MMP-2 and MMP-9 concentrations in arsenic-endemic population were significantly (p < 0.001) higher than those in non-endemic population. Both MMPs showed significant positive interactions with drinking water (rs = 0.208, p < 0.001 for MMP-2; rs = 0.163, p <0.01 for MMP-9), hair (rs= 0.163, p < 0.01 for MMP-2; rs = 0.173, p < 0.01 for MMP-9) and nail (rs= 0.160, p < 0.01 for MMP-2; rs = 0.182, p < 0.001 for MMP-9) arsenic of the study subjects. MMP-2 concentrations were 1.02, 1.03 and 1.05 times, and MMP-9 concentrations were 1.03, 1.06 and 1.07 times greater for 1 unit increase in log-transformed water, hair and nail arsenic concentrations, respectively, after adjusting for covariates (age, sex, BMI, smoking habit and hypertension). Furthermore, both MMPs were increased dose-dependently when the study subjects were split into three (≤10, 10.1-50 and > 50 μg/L) groups based on the regulatory upper limit of water arsenic concentration set by WHO and Bangladesh Government. MMPs were also found to be significantly (p < 0.05) associated with each other. Finally, the concentrations of both MMPs were correlated with several circulating markers related to CVDs.Conclusions: This study showed the significant positive associations and dose–response relationships of arsenic exposure with serum MMP-2 and MMP-9 concentrations. This study also showed the interactions of MMP-2 and MMP-9 concentrations with the circulating markers of CVDs suggesting the MMP-2 and MMP-9 -mediated mechanism of arsenic-induced CVDs.
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| 3078. |
- Islam, Md Shafiqul, 1984-, et al.
(författare)
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Peeling of metal foil from a compliant substrate
- 2021
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Ingår i: The journal of adhesion. - : Taylor & Francis. - 0021-8464 .- 1563-518X .- 1545-5823. ; 97:7, s. 672-703
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Tidskriftsartikel (refereegranskat)abstract
- Large displacement peel was studied for cases where a compliant substrate leads to a large value of the root rotation. An existing simplified beam model to calculate the peel fracture energy was modified to allow for a kinematic hardening beam model of the foil. The steady-state peel force and the root rotation were used as input data to the resulting analytical beam model. Test results from the literature were analysed. A more elaborate finite element model was also studied, using cohesive elements for the interface layer between the foil and the substrate. The cohesive zone parameters used were the fracture energy, the cohesive strength and a shape parameter. An optimization scheme for the cohesive zone parameters was developed and optimized against experimental steady-state peel force and root rotation. The optimization scheme was effective to characterize the cohesive parameters. The method yields similar values of fracture energy for the two peel angles, with the one for being slightly higher than for . The difference in fracture energies for different peel angles suggests that the fracture energy can be mode dependent.
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| 3079. |
- Islind, Anna Sigridur, 1985-, et al.
(författare)
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Individualized blended care for patients with colorectal cancer: the patient's view on informational support
- 2021
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Ingår i: Supportive Care in Cancer. - : Springer Science and Business Media LLC. - 0941-4355 .- 1433-7339. ; 29:6, s. 3061-3067
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Tidskriftsartikel (refereegranskat)abstract
- Purpose The number of colorectal cancer patient survivors is increasing. Information and support during and after treatment are requested by patients, but questions remain on what to provide. The aim of this study was to understand what informational needs colorectal cancer patients and survivors have, with a focus on the potential support given by patient peers and the use of blended care. Methods A qualitative study using focus groups was conducted with patients diagnosed at the same hospital at least one year prior to the initiation of the study. The focus group interviews were transcribed verbatim and analyzed using deductive content analysis. Results The need for informational support varied over time and depended on individual patient characteristics. Timing was crucial and patients requested options of blended care and informational support after treatment cessation. The patients felt alone after treatment and requested assistance in communication with their next-of-kin. They also identified the value of peer support, especially to contextualize knowledge provided by healthcare. Conclusion This study showed a need for focus on individualized informational support. Blended care through integrating communication with peers online could be one way to support patients, both to enable shared decision-making as well as to provide person-centered care.
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| 3080. |
- Islind, Anna Sigridur, et al.
(författare)
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Invisible Work Meets Visible Work : Infrastructuring from the Perspective of Patients and Healthcare Professionals
- 2021
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Ingår i: Proceedings of the 54th Hawaii International Conference on System Sciences. - : Hawaii International Conference on System Sciences. - 9780998133140 ; , s. 3556-3565
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Konferensbidrag (refereegranskat)abstract
- Increased patient engagement and the use of new types of data, such as patient-generated health data (PGHD) is shifting how work is performed in relation to healthcare. This change enables healthcare professionals to delegate parts of work previously conducted by them to patients. There is a consensus regarding the need for nurses and physicians to work seamlessly together to make healthcare flow, but the role and responsibility of patients are less researched. In this paper, we aim to fill that gap by focusing on the shift of work from healthcare professionals to patients from the perspective of i) patients and ii) healthcare professionals. We use infrastructuring as a lens to understand the design of everyday work and actions from both perspectives. The main contribution is an analysis of, and insights into, how the work of patients can support healthcare professionals along with a conceptualization of how infrastructuring processes within and outside of healthcare are interconnected.
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