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| 2. |
- Abraham, Getahun Yacob
(författare)
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Education for Democracy? : Life Orientation: Lessons on Leadeship Qualities and Voting in South African Comprehensive Schools
- 2010
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This study takes as its starting point how teachers understand, interpret and teach social development aspects of Life Orientation in South African comprehensive schools. The specific focus is on lessons on leadership qualities and voting for third grade learners in four schools, each dominated by either Black, Coloured, White or mixed groups of learners. Field work with an ethnographic approach and a qualitative strategy was used to gain access to empirical data. Policy and curriculum documents, guidelines and textbooks were used. Classroom observations in four classes and interviews with 14 third grade teachers were conducted. Theoretical concepts of construction, deconstruction and reconstruction are applied. Ulf P Lundgren’s Frame Factor Theory is used to study school organization. Basil Bernstein’s Pedagogical Devices are considered when examining the different levels of pedagogical activities. To be a teacher in South Africa one needs to attend at least two years of teacher education after completing high school. Teachers in the classes studied underwent their teacher education during apartheid years. Due to limited in-service training, they sometimes experience problems of understanding and interpreting the learning area, which they usually tackle by consulting documents, colleagues or school authorities. The learners’ understanding varied based on their family background and type of school they attended. There were enormous differences in material, financial and organisational resources between classes and schools. The resources for teaching leadership qualities and voting were not, however, different between the classes. The lessons were teacher dominated and direct transmission was used as a method. The way teachers facilitated the lesson on leadership qualities and voting varied but all showed some democratic shortcomings. Apart from answering questions, learners were neither invited nor encouraged to participate to further their understanding of the theme. Limited aspects of leadership qualities were discussed, individual leaders’ roles were emphasised and the teachers picked candidates for class leaders in three of the classes. It was also evident that the class environments were not suitable for critical or creative thinking and democratic upbringing. The schools reproduced norms, values, languages and cultures of the different groups. Officially, teachers emphasised the common national South African identity. This emphasis on national identity could disguise the injustice some groups experience in society.
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| 3. |
- Adekunle, Kayode
(författare)
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Bio-based Composites from Soybean Oil Thermosets and Natural Fibers
- 2011
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- In order to reduce over-dependency on fossil fuels and to create an environment that is free of non-degradable plastics, and most importantly to reduce greenhouse gas emission, bio-based products are being developed from renewable resources through intense research to substitute conventional petrochemical-based plastics with renewable alternatives and to replace synthetic fibers with natural fibers. Many authors have done quite a lot of work on synthesizing polymers from renewable origin. Polylactic acid (PLA) has been developed and characterized, and it was found that it has enormous potential and can serve as an alternative to conventional thermoplastics in many applications. Modification of the plant oil triglycerides has been discussed by many authors, and research is still going on in this area. The challenge is how to make these renewable polymers more competitive in the market, and if possible to make them 100% bio-based. There is also a major disadvantage to using a bio-based polymer from plant oils because of the high viscosity, which makes impregnation of fibers difficult. Although natural fibers are hydrophilic in nature, the problem of compatibility with the hydrophobic matrix must be solved; however, the viscosity of the bio-based resin from plant oils will complicate the situation even more. This is why many authors have reported blending of the renewable thermoset resin with styrene. In the process of solving one problem, i.e reducing the viscosity of the renewable thermoset resin by blending with reactive diluents such as styrene, another problem which we intended to solve at the initial stage is invariably being created by using a volatile organic solvent like styrene. The solution to this cycle of problems is to synthesize a thermoset resin from plant oils which will have lower viscosity, and at the same time have higher levels of functionality. This will increase the crosslinking density, and they can be cured at room temperature or relatively low temperature. In view of the above considerations, the work included in this thesis has provided a reasonable solution to the compounded problems highlighted above. Three types of bio-based thermoset resins were synthesized and characterized using NMR, DSC, TGA, and FT-IR, and their processability was studied. The three resins were subsequently reinforced with natural fibers (woven and non-woven), glass fibers, and Lyocell fiber and the resulting natural fiber composites were characterized by mechanical, dynamic mechanical, impact, and SEM analyses. These composites can be used extensively in the automotive industry, particularly for the interior components, and also in the construction and furniture industries. Methacrylated soybean oil (MSO), methacrylic anhydride-modified soybean oil (MMSO), and acetic anhydride-modified soybean oil (AMSO) were found to be suitable for manufacture of composites because of their lower viscosity. The MMSO and MSO resins were found to be promising materials because composites manufactured by using them as a matrix showed very good mechanical properties. The MMSO resin can completely wet a fiber without the addition of styrene. It has the highest number of methacrylates per triglyceride and high crosslink density.
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| 4. |
- Agnhage, Tove
(författare)
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Eco-designed functionalization of polyester fabric
- 2017
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- There is an increased awareness of the textile dyeing and finishing sector’s high impact on the environment due to high water consumption, polluted wastewater, and inefficient use of energy. To reduce environmental impacts, researchers propose the use of dyes from natural sources. The purpose of using these is to impart new attributes to textiles without compromising on environmental sustainability. The attributes given to the textile can be color and/or other characteristics. A drawback however, is that the use of bio-sourced dyes is not free from environmental concerns. Thus, it becomes paramount to assess the environmental impacts from using them and improve the environmental profile, but studies on this topic are generally absent.The research presented in this thesis has included environmental impact assessment, using the life cycle assessment (LCA) tool, in the design process of a multifunctional polyester (PET) fabric using natural anthraquinones. By doing so an eco-design approach has been applied, with the intention to pave the way towards eco-sustainable bio-functionalization of textiles.The anthraquinones were obtained from the root extracts of the madder plant (Rubia tinctorum L.), referred to as madder dye. The research questions were therefore formulated related to the use of madder dye. Three research questions have been answered: (I) Can madder dye serve as a multifunctional species onto a PET woven fabric? (II) How does the environmental profile of the dyeing process of PET with madder dye look like, and how can it be improved? (III) What are the main challenges in using LCA to assess the environmental impacts of textile dyeing with plant-based dyes?It is concluded that there is a potential for the madder dye to serve as a multifunctional species onto PET. Based on the encouraging result, a recommendation for future work would be to focus on the durability of the functionalities presented and their improvement potential, both in exhaustion dyeing and pad-dyeing. LCA driven process optimization of the exhaustion dyeing enabled improvement in every impact category studied. However, several challenges have been identified which need to be overcome for the LCA to contribute to the sustainable use of multifunctional plant-based species in textile dyeing. The main challenges are the lack of available data at the research stage and the interdisciplinary nature of the research arena. It is envisaged that if these challenges are addressed, LCA can contribute towards sustainable bio-functionalization of textiles.
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| 5. |
- Agrawal, Tarun Kumar
(författare)
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Contribution to development of a secured traceability system for textile and clothing supply chain
- 2019
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Secured traceability implies not only the ability to identify, capture, and share required information on product transformation throughout the supply chain (SC), but also the ability to ensure the security of the traceability data. Due to information asymmetry and lack of transparency, textile and clothing (T&C) industries often face challenges in implementing and maintaining sufficient traceability. The SC actors find it difficult to identify and track the suppliers and sub-suppliers involved. Additionally, the opaque and largely untraceable structure of the SC has enabled the easy intrusion of counterfeits. Hence, a secured traceability system is imperative to ensure that the required traceability data are captured and shared among SC actors, thereby allowing the tracking and tracing of the products in the SC. Further, a secured traceability system helps organizations in various decision-making processes and protects customers from counterfeits. This thesis contributes to the development of a secured traceability system for the T&C sector. It examines traceability at product and information levels, based on the system-of systems approach. At the product level, the thesis introduces a secured traceability tag that can be printed on the textile surface. The secured tag is hard to copy and is durable enough to withstand normal textile use, thus providing sufficient security besides product tagging for traceability implementation. At the information level, the thesis explores and classifies traceability data that can be shared at business-to-business and business-to customer levels for the implementation of secured traceability. Subsequently, a block chain-based traceability framework is proposed for the T&C supply chain to systematically capture and share data in the supply chain network. The proposed framework demonstrates the applicability of shared data infrastructure to traceability without a central authority and develops technology-based trust among the supply chain actors. It relies on no central authority, and has customized data privacy and accessibility rules, thus providing a unique opportunity, flexibility, and authority to all supply chain actors to trace their supply chains and create transparent and sustainable supply chain networks.
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| 6. |
- Ahlgren, Per
(författare)
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The effects of indexing strategy-query term combination on retrieval effectiveness in a Swedish full text database
- 2004
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This thesis deals with Swedish full text retrieval and the problem of morphological variation of query terms in the document database. The study is an information retrieval experiment with a test collection. While no Swedish test collection was available, such a collection was constructed. It consists of a document database containing 161,336 news articles, and 52 topics with four-graded (0, 1, 2, 3) relevance assessments. The effects of indexing strategy-query term combination on retrieval effectiveness were studied. Three of five tested methods involved indexing strategies that used conflation, in the form of normalization. Further, two of these three combinations used indexing strategies that employed compound splitting. Normalization and compound splitting were performed by SWETWOL, a morphological analyzer for the Swedish language. A fourth combination attempted to group related terms by right hand truncation of query terms. A search expert performed the truncation. The four combinations were compared to each other and to a baseline combination, where no attempt was made to counteract the problem of morphological variation of query terms in the document database. Two situations were examined in the evaluation: the binary relevance situation and the multiple degree relevance situation. With regard to the binary relevance situation, where the three (positive) relevance degrees (1, 2, 3) were merged into one, and where precision was used as evaluation measure, the four alternative combinations outperformed the baseline. The best performing combination was the combination that used truncation. This combination performed better than or equal to a median precision value for 41 of the 52 topics. One reason for the relatively good performance of the truncation combination was the capacity of its queries to retrieve different parts of speech. In the multiple degree relevance situation, where the three (positive) relevance degrees were retained, retrieval effectiveness was taken to be the accumulated gain the user receives by examining the retrieval result up to given positions. The evaluation measure used was nDCG (normalized cumulated gain with discount). This measure credits retrieval methods that (1) rank highly relevant documents higher than less relevant ones, and (2) rank relevant (of any degree) documents high. With respect to (2), nDCG involves a discount component: a discount with regard to the relevance score of a relevant (of any degree) document is performed, and this discount is greater and greater, the higher position the document has in the ranked list of retrieved documents. In the multiple degree relevance situation, the five combinations were evaluated under four different user scenarios, where each scenario simulated a certain user type. Again, the four alternative combinations outperformed the baseline, for each user scenario. The truncation combination had the best performance under each user scenario. This outcome agreed with the performance result in the binary relevance situation. However, there were also differences between the two relevance situations. For 25 percent of the topics and with regard to one of the four user scenarios, the set of best performing combinations in the binary relevance situation was disjunct from the set of best performing combinations in the multiple degree relevance situation. The user scenario in question was such that almost all importance was placed on highly relevant documents, and the discount was sharp. The main conclusion of the thesis is that normalization and right hand truncation (performed by a search expert) enhanced retrieval effectiveness in comparison to the baseline, irrespective of which of the two relevance situations we consider. Further, the three indexing strategy-query term combinations based on normalization were almost as good as the combination that involves truncation. This holds for both relevance situations.
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| 7. |
- Ahlryd, Sara
(författare)
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På gränsen till en ny värld : studenters informationspraktiker på väg mot arbetslivet
- 2019
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- With the increasing academisation of vocational educations the need for higher education to prove to students the relevance of theoretical domain knowledge to professional experience is growing. One way of doing so is to provide students with opportunities for professional training during the course of their studies. The aim of this thesis is to explore the ways in which professional training help students to connect education with working life. The study is carried out through a practice theoretical lens on students’ information practices. It also entails exploring how their information activities contribute to their socialization within workplace communities and to their construction of professional identities. Through qualitative semi-structured interviews, the empirically driven analysis shows that students’ appropriation of information practices during professional training support learning, socialization into a workplace as well as identification with their future professional roles. Students’ information practices can be viewed as significant tools in the process of transition between education and profession where they function as facilitators for learning and participation in workplace activities.
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| 8. |
- Ahlstrom, Linda
(författare)
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Improving Work Ability and Return to Work among Women on Long-term Sick Leave
- 2014
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The overall aim of this thesis was to gain new knowledge of factors and interventions that improve work ability and return to work (RTW) among women on long-term sick leave from human service organizations (HSOs). The specific aims of the studies were: to evaluate the associations between the self-rated Work Ability Index (WAI) and Work Ability Score (WAS), and the relationship with prospective sick leave, symptoms, and health (Paper I); to investigate whether intervention with myofeedback training or intensive muscular strength training could decrease pain and increase work ability among women with neck pain (Paper II); to examine the associations between workplace rehabilitation and the combination of supportive conditions at work with work ability and RTW over time (Paper III); and to explore experiences, views, and strategies in the rehabilitation process for RTW (Paper IV). This thesis is based on a prospective cohort study (n=324) and a randomized controlled study (RCT) (n=60, participants with neck pain). Both quantitative and qualitative methods were used. The data collection consisted of questionnaires, laboratory-observed data, register-based data, and interviews. The results showed a very strong association between WAI and WAS, and results predicted future sick leave degree, health-related quality of life, vitality, neck pain, self-rated general health, self-rated mental health, behavioral stress, and current stress (Paper I). In the RCT (Paper II), individuals in the myofeedback intervention group increased their vitality and work ability over time and individuals in the intensive musculoskeletal strength training group increased their WAI, WAS, and mental health over time. WAI, WAS, and RTW increased over time among individuals provided with workplace rehabilitation and supportive conditions at work (Paper III) such as a sense of feeling welcome back at work, influence at work, possibilities for development, degree of freedom at work, meaning of work, quality of leadership, social support, sense of community, and work satisfaction. Women described (Paper IV) how they were striving to work and how they had different views, strategies, and approaches in the rehabilitation process for RTW. They expressed a desire to work, their goals for work, and their wishes for work. In the rehabilitation process for RTW they described their interaction with stakeholders as either controlling the interaction or struggling in the interaction. They described strategies to cope with RTW in terms of yo-yo (fluctuating) working: yo-yo working as a strategy or yo-yo working as a consequence. This thesis identifies factors of importance in improving work ability and RTW among women on long-term sick leave from HSOs. For women with neck pain, the intervention study showed feasibility of the intervention and demonstrated improved work ability and decreased pain (Paper II). The intensive muscular strength training program, which is easy for the individual to learn and perform at home, was associated with increased work ability. The results regarding rehabilitation highlight the importance of integrating workplace rehabilitation with supportive conditions at work to increase work ability and improve RTW (Paper III). Women expressed that they were striving to work and that they wanted to work (Paper IV). These women were “going in and out” of work participation (yo-yo working) as a way to handle the rehabilitation process. For assessing the status and progress of work ability among women on long-term sick leave, the single-question WAS may be used as a compliment to the full WAI as a simple indicator (Paper I).
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| 9. |
- Akinbomi, Julius
(författare)
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Fermentative hydrogen and methane productions using membrane bioreactors
- 2015
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The role of energy as a stimulant for economic growth and environmental sustainabilityof any nation has made the focus on green fuels, including fermentative hydrogen (bioH2) andmethane (bioCH4), to be a priority for the World’s policy makers. Nigeria, as the most populousAfrican country, with worsening energy crisis, can benefit from the introduction of the bioH2 andbioCH4 technologies into the country’s energy mix, since such technologies have the potential ofgenerating energy from organic wastes such as fruit waste.Fruit waste was studied in detail in this work because of its great economic andenvironmental potential, as large quantities of the wastes (10–65% of raw fruit) are generatedfrom fruit consumption and processing. Meanwhile, bioH2 and bioCH4 productions involvinganaerobic microorganisms in direct contact with organic wastes have been observed to result insubstrate and product inhibitions, which reduce the gas yields and limit the application of thetechnologies on an industrial scale. For example, in this study, the first experimental work todetermine the effects of hydraulic retention times and fruit mixing on bioH2 production fromsingle and mixed fruits revealed the highest cumulative bioH2 yield to be equivalent to 30% ofthe theoretical yield. However, combining the fermentation process with the application ofmembrane encapsulated cells and membrane separation techniques, respectively, could reducesubstrate and product inhibitions of the microorganisms. This study, therefore, focused on theapplication of membrane techniques to enhance the yields of bioH2 and bioCH4 productions fromthe organic wastes.The second experimental work which focused on reduction of substrate inhibition,involved the investigation of the effects of the PVDF membrane encapsulation techniques on thebioH2 and bioCH4 productions from nutrient media with limonene, myrcene, octanol and hexanalas fruit flavours. The results showed that membrane encapsulated cells produced bioCH4 fasterand lasted longer, compared to free cells in limonene. Also, about 60% membrane protectiveeffect against myrcene, octanol and hexanal inhibitions was obtained. Regarding bioH2production, membrane encapsulated cells, compared to free cells, produced higher average dailyyields of 94, 30 and 77% with hexanal, myrcene and octanol as flavours, respectively. The finalpart of the study, which was aimed at reducing product inhibition, involved the study of theeffects of membrane permeation of volatile fatty acids (VFAs) on the bioreactor hydrodynamicsin relation to bioH2 production. The investigation revealed that low transmembrane pressure of104Pa was required to achieve a 3L h-1m-2 critical flux with reversible fouling mainly due to cakelayer formation, and bioH2 production was also observed to restart after VFAs removal.The results from this study suggest that membrane-based techniques could improve bioH2and bioCH4 productions from fermentation media with substrate and product inhibitions.
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| 10. |
- Aldrin, Viktor, 1980-
(författare)
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Prayer in Peasant Communities : Ideals and Practices of Prayer in the Late Medieval Ecclesiastical Province of Uppsala, Sweden
- 2010
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The aim of this study has been to identify, explain and delineate praying among peasant communities in the ecclesiastical province of Uppsala, Sweden. Four aspects have been examined through the perspectives of ideals and practices, namely the standards of prayer, devotional prayer, prayer in times of need and prayer cultures. The standards of prayer considered the physical and mental behaviour of the praying peasant woman or man. The most ordinary way to act during prayer was to stand with hands together, palm against palm, and to pray in the vernacular often using mental themes to enhance the devotion. Devotional prayers were foremost the three ‘standard’ prayers Paternoster, Hail Mary and Apostolic Creed, and could be used separately or combined. Prayer in times of need was possibly considered a matter of praying to saints, something that cannot be proven to have been either practiced or recommended on other, ordinary occasions where God and the Virgin Mary were considered the proper recipients of prayer. A few authentic prayers exist that were possibly said by peasant women and men in connection with miracles and these show the ability to construct elaborate prayers and to propose businesslike agreements with saints. These three prayers were required knowledge for a peasant woman or man and were put to the test in order to become a godparent, and were therefore made available in the vernacular by the parish priests. Ways to maintain the prayer cultures were through mnemonic techniques, and indulgences stipulating and confirming prayers used or to be used in connection with certain churches, days and places within the churches. Name saints could also be used, since the person and the name saint were considered to have a special bond. Prayer could also be used as protection for the living; since a prayer was considered to generate either merits or favours from a celestial patron to his or her client. The prayer life of those belonging to peasant communities was both elaborate and full of nuances.
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