| 1. |
- Broberg Viklund, Sarah, 1983-
(författare)
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System studies of the use of industrial excess heat
- 2015
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Energy, materials, and by-products, can be exchanged between companies, having positive effects in the form of improved resource efficiency, environmental benefits, and economic gains. One such energy stream that can be exchanged is excess heat, that is, heat generated as a by-product during, for example, industrial production. Excess heat will continue to play an important role in efforts to reduce greenhouse gas (GHG) emissions and improve energy efficiency. Using excess heat is therefore currently emphasized in EU policy as a way to reach EU climate targets.This thesis examines the opportunities of manufacturing industries to use industrial excess heat, and how doing so can positively affect industry, society, and the climate. Since different parts of the energy system are entangled, there is an inherent complexity in studying these systems and introducing excess heat in one part of the energy system may influence other parts of the system. This analysis has accordingly been conducted by combining studies from various perspectives, by applying both quantitative and qualitative methods and covering a broad range of aspects, such as technical possibilities as well as climate, policy, economics, and resource aspects.The results identify several opportunities and benefits accruing from excess heat use. Although excess heat is currently partly used as a thermal resource in district heating in Sweden, this thesis demonstrates that significant untapped excess heat is still available. The mapping conducted in the appended studies identifies excess heat in different energy carriers, mainly low-temperature water. Analysis of excess heat use in different recovery options demonstrated greater output when using excess heat in district heating than electricity production. Optimizing the trade-offs in excess heat used in a district heating network, heat-driven cooling, and electricity production under different energy market conditions while minimizing the system cost, however, indicated that the attractiveness of excess heat in district heating depends on the type of heat production in the system. Viewing excess heat as a low-cost energy source also makes it economically interesting, and creates opportunities to invest in excess heat-recovery solutions. Excess heat is often viewed as CO2 neutral since unused excess heat may be regarded as wasted energy. The GHG mitigation potential of using excess heat, however, was found to be ambiguous. The appended studies demonstrate that using excess heat for electricity production or for applications that reduce the use of electricity reduces GHG emissions. The effects of using excess heat in district heating, on the other hand, depend on the energy market development, for example, the marginal electricity production and marginal use of biomass, and on the type of district heating system replaced. The interviews performed reveal that energy policy does influence excess heat use, being demonstrated both to promote and discourage excess heat use. Beyond national energy policies, internal goals and core values were identified as important for improved energy efficiency and increased excess heat use.
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| 2. |
- Ek, Staffan, et al.
(författare)
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Relative Age Effect of Sport Academy Adolescents, a Physiological Evaluation
- 2020
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Ingår i: Sports. - Basel : MDPI. - 2075-4663. ; 8:1
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Tidskriftsartikel (refereegranskat)abstract
- The relationship between birth quarter distribution and physiological characteristics related to athletic skills, in adolescent sport academy students has not been fully investigated. In a cross-sectional study, we recruited 86 boys and 52 girls aged 12-14 years during their first term at a sport academy school. We measured body size, cardiac size, pulmonary function, body composition, lower body power, cardiorespiratory fitness parameters, and running endurance by standard methods and analyzed these estimates in relation to birth quarter by ANOVA. Birth quarter distribution in our cohort was compared with birth quarter distribution in the same ages in the whole of Sweden and analyzed by logistic regression. The academy had an overrepresentation of students born in the first quartile of the year compared to those born in the last quartile (odds ratio 2.3 (95% CI: 1.1-4.7)). When comparing the physiological characteristics between birth quarters, uniformity is prominent since out of 26 performed physiological and anthropometric tests only four showed statistically significant group differences. We thus believe that the selection process to the sport academy favours athletes with higher chronological age, i.e., a so-called relative age effect is present. © 2020 MDPI (Basel, Switzerland).
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| 3. |
- Ekström, Veronica, 1975-
(författare)
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Det besvärliga våldet : Socialtjänstens stöd till kvinnor som utsatts för våld i nära relationer
- 2016
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- I avhandlingen analyseras hur våldsutsatta kvinnors behov tolkas, omförhandlas och anpassas för att kunna hanteras inom socialtjänstens organisation. Avhandlingens övergripande frågeställningar fokuserar på insatser och behov, betydelsen av socialtjänstens organisering och betydelsen av socialarbetarnas handlingsutrymme. Avhandlingen baseras på kvalitativa analyser av statliga propositioner, intervjuer med socialarbetare och med kvinnor som varit utsatta för våld i nära relationer. Det teoretiska ramverket bygger bland annat på Frasers (1989) teoretiska perspektiv som tar sin utgångspunkt i samhällets tolkningar av människors/gruppers behov av stöd, nyinstitutionell teori och teorier om gatubyråkrater. Avhandlingen visar att socialarbetares tolkningar är centrala aspekter av förhandlingen om hur våldsutsatta kvinnors behov och rätt till stöd ska förstås. Ett viktigt resultat i avhandlingen är att stödet till våldsutsatta kvinnor blir så pass olika. Avhandlingen ger inga svar i kvantitativa termer på hur olikheten är fördelad, men den ger exempel på hur olikheten tar sig uttryck. I kommuner där specialiseringen innebär att socialarbetarna på socialkontoret i första hand utreder behov och fattar beslut om insatser, måste det också finnas adekvata insatser att besluta om. Saknas det så erbjuds inte heller något stöd. Stödet till kvinnor som utsatts för våld i nära relationer blir också olika eftersom socialarbetare ställer olika krav eller sätter upp olika trösklar för att kvinnor ska få stöd. Avhandlingen visar att både gemensam kunskap och gemensam syn på sociala problem är centralt för att samarbetet inom den specialiserade socialtjänstens ska fungera och i längden också för vilket stöd människor kommer att erbjudas.
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| 4. |
- Eriksson, Kalle, 1991-
(författare)
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Politicising automation : ideas on work, technology, and agency in the Swedish political debate
- 2024
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Over the last decade, rapid advancements in artificial intelligence and other automation technologies have sparked extensive and sometimes heated debates over the wider societal impacts of ongoing technological shifts. Even if there is wide agreement that policymaking will play a crucial role for how the future of automation will unfold, these debates tend to emphasise the technical and economic aspects of labour automation while largely overlooking its inherently political dimensions. In recent years, critical scholars within the social sciences have sought to challenge this narrow focus by bringing attention to the various biased effects that automation processes give rise to in terms of justice and power, but automation of labour as a political issue in and of itself remains underexplored. Given the broad acknowledgement of the importance of policymaking, what is especially needed is an increased understanding of how policymakers themselves interpret this issue, as well as their own roles in relation to it. This thesis aims to narrow this knowledge gap by examining the manifest and latent political ideas that underpin the ways in which Swedish policymakers interpret and negotiate the issue of automation, to thereby gain a fuller understanding of what key values that are at stake in the Swedish automation debate. To do so, an ideational analysis has been conducted using parliamentary documents, media and party texts, as well as semi-structured interviews with policymakers as data.The analysis shows that while Swedish policymakers generally perceive automation of labour as a non-contentious issue in Swedish politics, their ideas on the matter are informed by underlying normative and empirical assumptions that lead to conflicting conclusions regarding both the desirability of increased automation and the roles of policymaking for governing the technologies in question. The analysis also finds that actors’ views on automation are tightly connected to their views on a range of related, more fundamental, political issues – such as the character and values of human labour, and the role of the state in relation to the market. Since these related issues are indeed quite ideologically polarising in the Swedish context, the findings indicate that also automation is a more polarising issue than many policymakers perceive it to be. In other words, while the issue has yet to cause any explicit political conflicts in the Swedish debate, the identified disparities and ideational tensions clearly suggest that automation is not merely a technological inevitability but a complex, politically charged arena where different, if often latent, visions of the future contend.Thus, the portrayal of automation as a politically neutral phenomenon risks obscuring its inherently contestable character and preventing the critical ideological debates that therefore ought to surround it. By bringing our attention to the different and sometimes conflicting political ideas that automation is subject to, the thesis aims to contribute to a more politicised automation debate in which said ideas are not shied away from but openly contested and deliberated over. Such a debate would not only be more democratic, but also more likely to realise some of the unprecedented opportunities that automation technologies grant us.
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| 5. |
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| 6. |
- Jonsson, Joakim, 1984-
(författare)
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Integration of MRI into the radiotherapy workflow
- 2013
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The modern day radiotherapy treatments are almost exclusively based on computed tomography (CT) images. The CT images are acquired using x-rays, and therefore reflect the radiation interaction properties of the material. This information is used to perform accurate dose calculation by the treatment planning system, and the data is also well suited for creating digitally reconstructed radiographs for comparing patient set up at the treatment machine where x-ray images are routinely acquired for this purpose.The magnetic resonance (MR) scanner has many attractive features for radiotherapy purposes. The soft tissue contrast as compared to CT is far superior, and it is possible to vary the sequences in order to visualize different anatomical and physiological properties of an organ. Both of these properties may contribute to an increase in accuracy of radiotherapy treatment.Using the MR images by themselves for treatment planning is, however, problematic. MR data reflects the magnetic properties of protons, and thus have no connection to the radiointeraction properties of the material. MRI also has inherent difficulty in imaging bone, which will appear in images as areas of no signal similar to air. This makes both dose calculation and patient positioning at the treatment machine troublesome.There are several clinics that use MR images together with CT images to perform treatment planning. The images are registered to a common coordinate system, a process often described as image fusion. In these cases, the MR images are primarily used for target definition and the CT images are used for dose calculations. This method is now not ideal, however, since the image fusion may introduce systematic uncertainties into the treatment due to the fact that the tumor is often able to move relatively freely with respect to the patients’ bony anatomy and outer contour, especially when the image registration algorithms take the entire patient anatomy in the volume of interest into account.The work presented in the thesis “Integration of MRI into the radiotherapy workflow” aim towards investigating the possibilities of workflows based entirely on MRI without using image registration, as well as workflows using image registration methods that are better suited for targets that can move with respect to surrounding bony anatomy, such as the prostate.
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| 7. |
- Olofsson, Lennart, 1952-
(författare)
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Energy and intensity modulated radiation therapy with electrons
- 2005
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- In recent years intensity modulated radiation therapy with photons (xIMRT) has gained attention due to its ability to reduce the dose in the tissues close to the tumour volume. However, this technique also results in a large low dose volume. Electron IMRT (eIMRT) has the potential to reduce the integral dose to the patient due to the dose fall off in the electron depth dose curves. This dose fall off makes it possible to modulate the dose distribution in the direction of the beam by selecting appropriate electron energies. The use of a computer based energy selection method was examined in combination with the IMRT technique to optimise the electron dose distribution. It is clearly illustrated that the energy optimisation procedure reduces the dose to lung and heart in a breast cancer treatment. To shape the multiple electron subfields (beamlets) that are used in eIMRT, an electron multi leaf collimator (eMLC) is needed. However, photons produced in a conventional electron treatment head could penetrate such an added eMLC, thus producing an undesirable dose contribution. The leakage levels normally achieved are acceptable for standard single electron field treatments but could become unacceptably high in eIMRT treatments where a lot of small subfields are combined. To limit this photon contribution, the photon MLC (xMLC) was used to shield off large parts of the photon leakage. The effect of this xMLC shielding on the reduction of photon leakage, the electron beam penumbras, and electron output (dose level), was studied using Monte Carlo methods for different electron treatment head designs. The use of helium as a mean to reduce the electron scatter in the treatment head, and thus the perturbating effect of the xMLC on electron beam penumbra and output, was also investigated. This thesis shows that the effect of the xMLC shielding on the electron beam penumbra and output can be made negligible while still obtaining a significantly reduced x-ray leakage dose contribution. The result is a large gain in radiation protection of the patient and a better dynamic range for the eIMRT dose optimisation. For this optimisation a computer based electron energy selection method was developed and tested on two clinical cases.
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| 8. |
- Angelov, Angel G., 1983-
(författare)
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Methods for interval-censored data and testing for stochastic dominance
- 2018
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This thesis includes four papers: the first three of them are concerned with methods for interval-censored data, while the forth paper is devoted to testing for stochastic dominance.In many studies, the variable of interest is observed to lie within an interval instead of being observed exactly, i.e., each observation is an interval and not a single value. This type of data is known as interval-censored. It may arise in questionnaire-based studies when the respondent gives an answer in the form of an interval without having pre-specified ranges. Such data are called self-selected interval data. In this context, the assumption of noninformative censoring is not fulfilled, and therefore the existing methods for interval-censored data are not necessarily applicable.A problem of interest is to estimate the underlying distribution function. There are two main approaches to this problem: (i) parametric estimation, which assumes a particular functional form of the distribution, and (ii) nonparametric estimation, which does not rely on any distributional assumptions. In Paper A, a nonparametric maximum likelihood estimator for self-selected interval data is proposed and its consistency is shown. Paper B suggests a parametric maximum likelihood estimator. The consistency and asymptotic normality of the estimator are proven.Another interesting problem is to infer whether two samples arise from identical distributions. In Paper C, nonparametric two-sample tests suitable for self-selected interval data are suggested and their properties are investigated through simulations.Paper D concerns testing for stochastic dominance with uncensored data. The paper explores a testing problem which involves four hypotheses, that is, based on observations of two random variables X and Y, one wants to discriminate between four possibilities: identical survival functions, stochastic dominance of X over Y, stochastic dominance of Y over X, or crossing survival functions. Permutation-based tests suitable for two independent samples and for paired samples are proposed. The tests are applied to data from an experiment concerning the individual's willingness to pay for a given environmental improvement.
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| 9. |
- Boström, Magnus, 1972-, et al.
(författare)
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IKEA and the Responsible Governance of Supply Chains : IKEA’s work on chemicals in textiles
- 2013
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- This report focuses on IKEA’s management and communication surrounding sustainability in general and chemical risks specifically. IKEA’s work is analysed in relation to theoretical concepts around responsibility, supply chain, and governance . The report focuses on IKEA’s visions and organizational structures, its policy instruments to deal with chemical risks, supplier-relations and communication and learning. The study is based on previous scholarly literature, analyses of relevant documents, a field visit at a few of IKEA’s suppliers in southern India, as well as interviews with staff working at IKEA in Sweden. The report focuses on IKEA’s systems and processes for dealing with chemical risks, and not on the implementation of such measures in quantitative terms.
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| 10. |
- Braunerhielm, Lotta
(författare)
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Plats för kulturarv och turism : Grythyttan - en fallstudie av upplevelser, värderingar och intressen
- 2006
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This thesis focuses on the tension between cultural heritage and tourism development. A case study was carried out in Grythyttan, a cultural-historical place, located in the municipality of Hällefors in Bergslagen. The central aim of the study is to explore, understand and interpret the tensions between cultural heritage and tourism. The ambition has been to focus upon the consequences of the increased interest from the tourism industry in cultural heritage and the increased interest from the cultural heritage sector in tourism and on creating heritage-based experiences. Grythyttan represents the place where the complex of problems is illustrated. The aim involves a description of characteristics of cultural heritage and tourism and how they are experienced with regards to a historical-geographical perspective. This is considered in contrast to the increased commercialization in society. The method has been to study how the place, cultural heritage and tourism are experienced by different actors, those who live, work and visit the place. The three actor groups who were studied were producers, consumers/visitors and locals. The producers were representatives of both the tourism and cultural heritage sector and from the municipality.What has happened at the place is characteristic of our time, i.e. the commercialization of places and an adjustment to the tourism market. Grythyttan has been transformed into a tourism destination with a profile of meal. The whole municipality has purposely erased an old identity associated with the history of coalmining and ironworks. This has contributed to a clear distinction between a ‘place’ and a ‘destination’. This also highlights two different perspectives of the actors, those who bring out the importance of the heritage and those who look upon the heritage and the place from a commercial perspective. Visitors are offered a commercial place and an experience of the meal destination but are not offered the story of ‘the place’.The concluding remarks are that the ‘place’ Grythyttan is associated with a strong identity anchored in its historical-geographical context and strongly associated with locals and the heritage sector. The cultural heritage gives way to tourism and meal. Heritage is not a part of and not ‘given place’ in the tourism destination of meal.
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