| 1. |
- Jönsson, Daniel, 1984-, et al.
(författare)
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Inviwo - A Visualization System with Usage Abstraction Levels
- 2020
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Ingår i: IEEE Transactions on Visualization and Computer Graphics. - : IEEE. - 1077-2626 .- 1941-0506. ; 26:11, s. 3241-3254
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Tidskriftsartikel (refereegranskat)abstract
- The complexity of todays visualization applications demands specific visualization systems tailored for the development of these applications. Frequently, such systems utilize levels of abstraction to improve the application development process, for insta
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| 2. |
- Compañero, Reinol Josef, et al.
(författare)
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A value of information approach to recycling
- 2024
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Ingår i: Resources, Conservation and Recycling. - : Elsevier BV. - 0921-3449 .- 1879-0658. ; 209
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Tidskriftsartikel (refereegranskat)abstract
- Uncertainties with respect to the chemical composition of scrap limit its suitability as an input to recycling. This study offers an alternative approach in dealing with this concern and explores the hypothetical case where this uncertainty is nonexistent. The effect of fully knowing the scrap composition is simulated using an optimization software adopted to scrap-based, stainless-steel production. Through the systematic implementation of this information-driven model in the studied cases, the results suggest that with access to perfect information, recycling incentives can be realized. Essentially, the steel scraps’ consumption increased since it was possible to select and combine scrap quantities with varying composition profiles to achieve the targeted product compositions. This also meant that elements already in the scrap were allocated in a manner that was less dependent on pure alloy additions. Being able to demonstrate the value of information on scrap composition could rationalize upgrades on current scrap management systems.
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| 3. |
- Compañero, Reinol Josef, et al.
(författare)
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Appraising the value of compositional information and its implications to scrap-based production of steel
- 2023
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Ingår i: Mineral Economics. - : Springer Nature. - 2191-2203 .- 2191-2211.
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Tidskriftsartikel (refereegranskat)abstract
- The current nature of steel design and production is a response to meet increasingly demanding applications but without much consideration of end-of-life scenarios. The scrap handling infrastructure, particularly the characterization and sorting, is unable to match the complexity of scrapped products. This is manifested in problems of intermixing and contamination in the scrap flows, especially for obsolete scrap. Also, the segmentation of scrap classes in standards with respect to chemical compositions is based on tolerance ranges. Thus, variation in scrap composition exists even within the same scrap type. This study applies the concept of expected value of perfect information (EPVI) to the context of steel recycling. More specifically, it sets out to examine the difference between having partial and full information on scrap composition by using a raw material optimization software. Three different scenarios with different constraints were used to appraise this difference in terms of production and excess costs. With access to perfect information, production costs decreased by 8–10%, and excess costs became negligible. Overall, comparing the respective results gave meaningful insights on the value of reestablishing the compositional information of scrap at the end of its use phase. Furthermore, the results provided relevant findings and contribute to the ongoing discussions on the seemingly disparate prioritization of economic and environmental incentives with respect to the recycling of steel.
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| 4. |
- Compañero, Reinol Josef, 1987-
(författare)
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Recirculation of scrapped resources : The role of material information in enhancing the sustainability of recycling
- 2024
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Industries have responded to the climate change problem by positioning their activities as compatible with concepts such as the Circular Economy. Conveying the idea of maximizing and keeping the resources in a manner that aligns with the principles of sustainable development, the endorsements for implementing circularity measures has arguably become a boon for businesses. Firms that have traditionally consumed both primary and anthropogenic resources in the production of materials used in infrastructure, transportation, and other technological requirements are in a special position. On the one hand, their products are needed for societal development. But on the other hand, their activities emit considerable amounts of greenhouse gases.The steel industry is a classic example where material and energy resource savings are achieved when the End-of-Life (EoL) products are recycled. However, these assumed efficiencies are provisional to scrap being a suitable replacement for ore-based resources. The replacement of primary (i.e. purer) - with secondary (i.e. contaminated) as feedstock for production depends heavily on a recycling system’s capability to deal with the complexity of the ferrous scrap streams that society is generating. More specifically, in reference to recovering the material identity through characterization and sorting that lessens or avoids the current practice of either diluting contaminants or compensating for insufficient alloying through addition of primary resources.This present thesis takes a critical look at the use of scrap with the view that recycling is a technical process that is carried out by enterprises. The impression that recycling consequently replaces the use of primary resources is scrutinized, with consideration of scrap as a characteristically appropriate, but innately challenging feedstock to use. Case studies focusing on the Swedish scrap-based production context revealed that the recycling system actors operate and transact on the basis ofscrap’s quality, which in turn was interpreted as being multidimensional and dependent on each actor’s preferences. The alignment of economic and environmental interests connected with scrap utilization was found to be limited, with companies preferring the use of primary resources when scrap is no longer suitable.The idea of suitability was then ascribed to compositional information regarding scrap and tested at two levels: having access to partial or full information. The former is what is achieved through the current scrap handling in the reverse loop while the latter is an idealized situation where the exact chemistry of the scrap is known. An optimization program was then used to simulate steel recycling where the scenarios tested were designed to focus on the response of the production model to the scrap chemistry of the input materials. The results obtained showed an overall decrease in production costs and an increase in the proportion of scrap used in production. In most cases, this was attributed to the flexibility to allocate scrap based on its composition to the closest matching target products.Finally, additional interviews with industry practitioners further clarified established, company-based protocols for dealing with the lack of information and provided insights with regard to opportunities for increasing scrap utilization. An analysis of the responses suggested that there are contextual differences when it comes to practices by each company, and even attitudes, towards anthropogenic resources. Ultimately, the insights from this thesis lend support to the need of enterprises to address the trade-offs related to scrap utilization and lead to enhanced sustainability in steel recycling.
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| 5. |
- Sayols-Baixeras, Sergi, et al.
(författare)
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Streptococcus Species Abundance in the Gut Is Linked to Subclinical Coronary Atherosclerosis in 8973 Participants From the SCAPIS Cohort
- 2023
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Ingår i: Circulation. - : Lippincott Williams & Wilkins. - 0009-7322 .- 1524-4539. ; 148:6, s. 459-472
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Tidskriftsartikel (refereegranskat)abstract
- Background: Gut microbiota have been implicated in atherosclerotic disease, but their relation with subclinical coronary atherosclerosis is unclear. This study aimed to identify associations between the gut microbiome and computed tomography-based measures of coronary atherosclerosis and to explore relevant clinical correlates.Methods: We conducted a cross-sectional study of 8973 participants (50 to 65 years of age) without overt atherosclerotic disease from the population-based SCAPIS (Swedish Cardiopulmonary Bioimage Study). Coronary atherosclerosis was measured using coronary artery calcium score and coronary computed tomography angiography. Gut microbiota species abundance and functional potential were assessed with shotgun metagenomics sequencing of stool, and associations with coronary atherosclerosis were evaluated with multivariable regression models adjusted for cardiovascular risk factors. Associated species were evaluated for association with inflammatory markers, metabolites, and corresponding species in saliva.Results: The mean age of the study sample was 57.4 years, and 53.7% were female. Coronary artery calcification was detected in 40.3%, and 5.4% had at least 1 stenosis with >50% occlusion. Sixty-four species were associated with coronary artery calcium score independent of cardiovascular risk factors, with the strongest associations observed for Streptococcus anginosus and Streptococcus oralis subsp oralis (P<1×10-5). Associations were largely similar across coronary computed tomography angiography-based measurements. Out of the 64 species, 19 species, including streptococci and other species commonly found in the oral cavity, were associated with high-sensitivity C-reactive protein plasma concentrations, and 16 with neutrophil counts. Gut microbial species that are commonly found in the oral cavity were negatively associated with plasma indole propionate and positively associated with plasma secondary bile acids and imidazole propionate. Five species, including 3 streptococci, correlated with the same species in saliva and were associated with worse dental health in the Malmö Offspring Dental Study. Microbial functional potential of dissimilatory nitrate reduction, anaerobic fatty acid β-oxidation, and amino acid degradation were associated with coronary artery calcium score.Conclusions: This study provides evidence of an association of a gut microbiota composition characterized by increased abundance of Streptococcus spp and other species commonly found in the oral cavity with coronary atherosclerosis and systemic inflammation markers. Further longitudinal and experimental studies are warranted to explore the potential implications of a bacterial component in atherogenesis.
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