| 1. |
- Afewerki, Samson, 1985-
(författare)
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Development of catalytic enantioselective C-C bond-forming and cascade transformations by merging homogeneous or heterogeneous transition metal catalysis with asymmetric aminocatalysis
- 2014
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Chiral molecules play a central role in our daily life and in nature, for instance the different enantiomers or diastereomers of a chiral molecule may show completely different biological activity. For this reason, it is a vital goal for synthetic chemists to design selective and efficient methodologies that allow the synthesis of the desired enantiomer. In this context, it is highly important that the concept of green chemistry is considered while designing new approaches that eventually will provide more environmental and sustainable chemical synthesis.The aim of this thesis is to develop the concept of combining transition metal catalysis and aminocatalysis in one process (dual catalysis). This strategy would give access to powerful tools to promote reactions that were not successful with either transition metal catalyst or the organocatalyst alone. The protocols presented in this thesis based on organocatalytic transformations via enamine or iminium intermediates or both, in combination with transition metal catalysis, describes new enantioselective organocatalytic procedures that afford valuable compounds with high chemo- and enantioselectivity from inexpensive commercial available starting materials. In paper I, we present a successful example of dual catalysis: the combination of transition metal activation of an electrophile and aminocatalyst activation of a nucleophile via enamine intermediate. In paper II, the opposite scenario is presented, here the transition metal activates the nucleophile and the aminocatalyst activates the electrophile via an iminium intermediate. In paper III,we present a domino Michael/carbocyclisation reaction that is catalysed by a chiral amine (via iminium/enamine activation) in combination with a transition metal catalysts activation of an electrophile. In paper IV, the concept of dual catalysis was further extended and applied for the highly enantioselective synthesis of valuable structural scaffolds, namely poly-substituted spirocyclic oxindoles. Finally, in paper V the concept of dual catalysis was expanded, by investigating more challenging and environmentally benign processes, such as the successful combination of a heterogeneous palladium and amine catalysts for the highly enantioselective synthesis of functionalised cyclopentenes, containing an all carbonquaternary stereocenter, dihydrofurans and dihydropyrrolidines.
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| 2. |
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| 3. |
- Ahonen, Mikko, PhD, post-doc researcher, 1968-
(författare)
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Designing an Information System for Open Innovation – Bridging the Gap between Individual and Organisational Creativity
- 2011
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- History shows that those companies that continue to invest in their innovative capabilities during tough economic times are often those that prosper when growth returns. Recently, information systems (IS) have been harnessed to support innovation. Even with IS support, innovation campaigns and suggestion management systems often end up in failure. Employees and customers are reluctant to share their best ideas. Individuals interests, motivation, creativity and life-long learning are seldom adequately supported by companies. In the information systems research area there is very little research on creativity and creativity has traditionally been studied mainly within the decision support systems (DSS) research area. This DSS area has focused on rather mechanistic idea-generation processes lacking a focus on individuals and their creativity. Even in the emerging open innovation paradigm, individual and group levels have come in for little research. From these starting points, we became interested in ways to improve existing information systems and innovation practices. The research question here is: How to design an artefact to support learning and creativity within the open innovation paradigm. Since we are interested in building new artefacts, we will utilise design research methods, particularly the Design Science Research Methodology (DSRM) process model. Our three artefacts are the results of our work. The first artefact, the Mobile Personal Development Plan, is focused on extending development talks between an employer and employees within human resource management to support innovation. Curiosity and emerging interests are seen here as idea seeds and future competences. The second artefact, the iPortfolio, extends this with a life-long learning and problem-solving focus. The third artefact, the Brokering Platform for Open Innovation, finally focuses on collaboration with customers and crowds. The software development was time consuming in our work and only the first artefact is demonstrated as a functional software prototype. Our pilot in an SME company illustrates practical requirements and usability issues related to the software. Additionally, a Delphi study with international open innovation experts served to identify future related requirements. Given the lack of creativity research in the IS field, we claim that our work makes an appropriate contribution. To the design research literature our input is new usage cases of the previously mentioned DSRM process model. Our results apply to organisations, where the employees work in dispersed teams and need an information system to communicate their emerging ideas and interests for more systematic problem-solving. The managers in our study reported that there are plenty of ideas available, but the challenge is to ensure the commitment of external resources to the actual innovation building. The integration of learning into the innovation and problem-solving activity should be motivational. We therefore discuss human resource management in relation to creativity and innovation. Surprisingly, in our pilots we noticed difficulties in time management in mobile settings and the current health risk debate gradually changed our artefact design, so this work also provides a critical view on mobility and on the access anytime, anywhere phenomenon. Finally, we suggest improvements to existing innovation practices in organisations.
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| 4. |
- Ainegren, Mats
(författare)
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Roller skis' rolling resistance and grip characteristics : influences on physiological and performance measures in cross-country skiers
- 2012
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The aim of this thesis was to investigate roller ski characteristics; classical and freestyle roller skis’ rolling resistance coefficients (μR) and classical style roller skis’ static friction coefficients (μS), and to study the influence of different μR and μS on cross-country skiers’ performance and both physiological and biomechanical indices. The aim was also to study differences in skiing economy and efficiency between recreational skiers, female and male junior and senior elite cross-country skiers.The experiments showed that during a time period of 30 minutes of rolling on a treadmill (warm-up), μR decreased significantly (p<0.05) to about 60-65 % and 70-75 % of its initial value for freestyle and classical roller skis respectively. Also, there was a significant influence of normal force on μR, while different velocities and inclinations of the treadmill only resulted in small changes in μR.The study of the influence on physiological variables of a ~50 % change in μR showed that during submaximal steady rate exercise, external power, oxygen uptake, heart rate and blood lactate were significantly changed, while there were non-significant or only small changes to cycle rate, cycle length and ratings of perceived exertion. Incremental maximal tests showed that time to exhaustion was significantly changed and this occurred without a change in maximal power, maximal oxygen uptake, maximal heart rate and blood lactate, and that the influence on ratings of perceived exertion was non-significant or small.The study of classical style roller skis μS showed values that were five to eight times more than the values of μS reported from on-snow skiing with grip-waxed cross-country skis.The subsequent physiological and biomechanical experiments with different μS showed a significantly lower skiing economy (~14 % higher v̇O2), higher heart rate, lower propulsive forces coming from the legs and shorter time to exhaustion (~30 %) when using a different type of roller ski with a μS similar to on-snow skiing, while there was no difference between tests when using different pairs of roller skis with a (similar) higher μS.The part of the thesis which focused on skiing economy and efficiency as a function of skill, age and gender, showed that the elite cross-country skiers had better skiing economy and higher gross efficiency (5-18 %) compared with the recreational skiers, and the senior elite had better economy and higher efficiency (4-5 %) than their junior counterparts, while no differences could be found between the genders.
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| 5. |
- Alam, Mohammad Anzar
(författare)
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Online optical method for real-time surface measurement using line-of-light triangulation
- 2013
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Real time paper surface-web measurement is one of the challenging research fields. The traditional laboratory method has many limitations and is unable to measure the entire tambour during the manufacturing process. It has been necessary to develop an online technique that could measure the surface topography in real time. An optical technique was developed, based on laser triangulation, and is applied to develop a new prototype device, which characterizes high speed paper-web surfaces over a wide scale of spatial wavelengths spectrum and computes the surface roughness in real time. The used multi channel pulsed laser diode, source of illumination onto the paper-web, is of benefit due to its low coherence length and is capable to deliver a powerful burst of light beam over a 1 µs duration, which delivers energy of 100 µJ per pulse. The short exposure time avoids blurriness in the acquired images which could possible due to the high speed and vibrations on the paper-web.The laser beam is shaped into a narrow line-of-light using cylindrical lenses and is projected onto a paper-web surface, which covers a physical length of about 210 mm. The created line-of-light cross section full width at half maximum, FWHM Gaussian distribution, is 2-3 pixels on the image. The line-of-light is projected onto the paper-web perpendicular to the plane of the surface. The low angled, low specular, reduced coherence length, scattered reflected laser line is captured by the 3 CCD sensors, which are synchronized with the laser source. The low specular light ensures to avoid saturation of the imaging sensors if the surface is very smooth, and obliquely captures the z-directional fine feature of the surface.The scattered phenomenon of the reflected light is responsible for the surface irregularity measurements. The basic image processing algorithm is applied in order to remove noise and cropped the images widthwise so that only pixels above a preset threshold gray level can be processed, which enables efficient real time measurement. The image is transformed into a 1D array using the center of gravity, COG. The accuracy and precision of the COG depends on the line-of-light FWHM, which, in turn, is responsible for the accuracy, noise and the resolution of the developed technique. The image subpixel resolution achieved is 0.01 times a pixel and uuncertainty in the raw data is 0.43 µm while it is 0.05 µm in the rms roughness.The signal processing steps combining the B-Spline filter and the filter in the spatial frequency domain were employed in order to separate roughness, waviness, and form and position error in the raw profile. The prototype is designed to measure online surface roughness and to characterize surface in a spatial wavelength spectrum from 0.09 to 30 mm, which is extendable to any required spatial range in order to cover a wide scale surface feature such as micro roughness, macro roughness and waviness. It is proven that exploitation of a simple laser triangulation technique could lead to an improvement in the overall quality and efficiency in the paper and paperboard industries and it can also be of potential interest for the other surface characterization problems.
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| 6. |
- Ambatipudi, Radhika, 1982-
(författare)
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High Frequency (MHz) Planar Transformers for Next Generation Switch Mode Power Supplies
- 2013
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Increasing the power density of power electronic converters while reducing or maintaining the same cost, offers a higher potential to meet the current trend inrelation to various power electronic applications. High power density converters can be achieved by increasing the switching frequency, due to which the bulkiest parts, such as transformer, inductors and the capacitor's size in the convertercircuit can be drastically reduced. In this regard, highly integrated planar magnetics are considered as an effective approach compared to the conventional wire wound transformers in modern switch mode power supplies (SMPS). However, as the operating frequency of the transformers increase from several hundred kHz to MHz, numerous problems arise such as skin and proximity effects due to the induced eddy currents in the windings, leakage inductance and unbalanced magnetic flux distribution. In addition to this, the core losses whichare functional dependent on frequency gets elevated as the operating frequency increases. Therefore, this thesis provides an insight towards the problems related to the high frequency magnetics and proposes a solution with regards to different aspects in relation to designing high power density, energy efficient transformers.The first part of the thesis concentrates on the investigation of high power density and highly energy efficient coreless printed circuit board (PCB) step-down transformers useful for stringent height DC-DC converter applications, where the core losses are being completely eliminated. These transformers also maintain the advantages offered by existing core based transformers such as, high coupling coefficient, sufficient input impedance, high energy efficiency and wide frequencyband width with the assistance of a resonant technique. In this regard, several coreless PCB step down transformers of different turn’s ratio for power transfer applications have been designed and evaluated. The designed multilayered coreless PCB transformers for telecom and PoE applications of 8,15 and 30W show that the volume reduction of approximately 40 - 90% is possible when compared to its existing core based counterparts while maintaining the energy efficiency of the transformers in the range of 90 - 97%. The estimation of EMI emissions from the designed transformers for the given power transfer application proves that the amount of radiated EMI from a multilayered transformer is lessthan that of the two layered transformer because of the decreased radius for thesame amount of inductance.The design guidelines for the multilayered coreless PCB step-down transformer for the given power transfer application has been proposed. The designed transformer of 10mm radius has been characterized up to the power level of 50Wand possesses a record power density of 107W/cm3 with a peak energy efficiency of 96%. In addition to this, the design guidelines of the signal transformer fordriving the high side MOSFET in double ended converter topologies have been proposed. The measured power consumption of the high side gate drive circuitvitogether with the designed signal transformer is 0.37W. Both these signal andpower transformers have been successfully implemented in a resonant converter topology in the switching frequency range of 2.4 – 2.75MHz for the maximum load power of 34.5W resulting in the peak energy efficiency of converter as 86.5%.This thesis also investigates the indirect effect of the dielectric laminate on the magnetic field intensity and current density distribution in the planar power transformers with the assistance of finite element analysis (FEA). The significanceof the high frequency dielectric laminate compared to FR-4 laminate in terms of energy efficiency of planar power transformers in MHz frequency region is also explored.The investigations were also conducted on different winding strategies such as conventional solid winding and the parallel winding strategies, which play an important role in the design and development of a high frequency transformer and suggested a better choice in the case of transformers operating in the MHz frequency region.In the second part of the thesis, a novel planar power transformer with hybrid core structure has been designed and evaluated in the MHz frequency region. The design guidelines of the energy efficient high frequency planar power transformerfor the given power transfer application have been proposed. The designed corebased planar transformer has been characterized up to the power level of 50W and possess a power density of 47W/cm3 with maximum energy efficiency of 97%. This transformer has been evaluated successfully in the resonant converter topology within the switching frequency range of 3 – 4.5MHz. The peak energy efficiency ofthe converter is reported to be 92% and the converter has been tested for the maximum power level of 45W, which is suitable for consumer applications such as laptop adapters. In addition to this, a record power density transformer has been designed with a custom made pot core and has been characterized in thefrequency range of 1 - 10MHz. The power density of this custom core transformer operating at 6.78MHz frequency is 67W/cm3 and with the peak energy efficiency of 98%.In conclusion, the research in this dissertation proposed a solution for obtaining high power density converters by designing the highly integrated, high frequency(1 - 10MHz) coreless and core based planar magnetics with energy efficiencies inthe range of 92 - 97%. This solution together with the latest semiconductor GaN/SiC switching devices provides an excellent choice to meet the requirements of the next generation ultra flat low profile switch mode power supplies (SMPS).
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| 7. |
- Andersson, Ewa, 1980-
(författare)
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Oberoendets praktik
- 2013
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The Independent PracticeDuring the last hundred years, the music industry has evolved with the record labels playing a central role. However, many argue that this situation is about to change as record sales have decreased during the last ten years. This imminent change in the music industry will not only affect the multinational record labels, but also the independent record labels. As record sales have decreased during the last ten years, the number of members in the Swedish Independent Music Producers Association (SOM) has increased and the association now includes 300 independent record labels which are responsible for around 30 percent of the music being produced in Sweden. However, they can be considered a dominated group within the music industry, since they only have around 10 percent of the total market shares when it comes to selling figures. Considering the changes in record sales, the domination of the major record labels and the somewhat fascinating growth of independent actors during turbulent times, this thesis will study how the Swedish independent actors relate to the practices and ideals relevant in the daily work of running an independent record label. The practices studied in this thesis are the practice of work, the practice of recognition and the practice of content production.The purpose of this thesis is to analyse how independence is constructed among the members of SOM. The thesis is based on material collected in a web survey as well as seven interviews with representatives of indie labels. The web survey was distributed to all members of SOM, and the interviewed informants were selected by snowball sampling, using a locator to find informants. The survey material was analysed with cluster and variance analysis, while the interview material was analysed using content analysis – searching for themes connected to the practices. All material is understood through the theoretical frame of the field theory.The main results of the study are that there are different ways of relating to practices among the Swedish independent actors, and that these ways of relating are closely connected to their position within the field. There are common ways of relating to practices such as always promoting DIY, the importance of music and the need to resist the dominance of the major labels. However, the independent actors are not consistent in how these commonalities work in practice. For example, DIY is not applied if it is not economically necessary, and the need to resist the major labels is only apparent when the independent actor has a weaker position within the field. The more established an independent actor is within the field, the lesser resistant he is against the dominating structures of the music industry. As a result of a weakening resistance against the major labels, the independent actors turn to struggle each other.
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| 8. |
- Andresen, Edith
(författare)
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Dressed for success : designing and managing regional strategic networks
- 2011
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Inter-organizational network initiatives such as regional strategic networks (RSNs) are often used by firms and public agencies to support regional development and competitiveness. RSNs are designed networks managed by a hub and financed by public or private means. RSN management is complex as members are autonomous and initially often loosely connected. The effects of RSNs on regional development are disputed as engineered relationship development may interfere with ongoing business relationships. Despite this, vast public funds are being invested in collaborative initiatives. Identifying factors affecting RSN performance will provide a better basis for evaluating and managing such initiatives.Based on concepts such as actors, resources, and activities findings are reported from longitudinal case-studies built on interviews with 68 members and hubs in four RSNs. Data were also collected through participant observation, conversations, archival data and emails. Findings indicate that factors such as evaluation criteria, member composition, relationships, location, goals, the hub, physical and human resources, knowledge sharing and development, resources, policies and norms, social activities, and communication exert an impact on entrepreneurship and cooperation.The first paper focuses on factors such as actor composition, actor goals, number of actors, and activities facilitating relationship development and commitment. The second paper identifies a framework of seven tasks to be performed by the hub. The effects on development of preferences and atmosphere are dealt with in the third paper. Effects of cooperation between public/private sector and universities are addressed in the fourth paper, and entrepreneurial processes in network contexts are analyzed in the fifth one.The important management role of the hub is emphasized as is carefully considered member composition. Relationships and commitment are found to be crucial. These factors are not covered by national and regional performance criteria. They merit a place of their own.
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| 9. |
- Arvidson, Catarina, 1959-
(författare)
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Genuspedagogers berättelser om makt och kontroll
- 2014
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- In this thesis 14 gender pedagogues’ stories about power and control are described and analysed. Here the term gender pedagogue refers to educators who have participated in further training in gender and gender equality studies. The training programme was the result of an initiative taken by the former Social Democratic government. The intention of the government was that those who participated in the training programme would then work as resource persons in the work for gender equality in preschools and schools (Frånberg, 2010; Regeringen, 2001a, 2001b; Wahlgren, 2009). The purpose of this study is to describe and analyse the gender pedagogues’ access to power and control in work for change. The theoretical framework chosen for the study consists of Basil Bernsteins concepts classification and framing (Bernstein, 1977, 2000) and Hildur Ve’s (1999a, 1999b) use of the concepts technical limited rationality and care work rationality. The empirical evidence is based on observations in a seminar series on gender issues and semi-structured interviews. The results of the interviews are presented as stories which have been created in the interplay between the gender pedagogues and the interviewer. One conclusion that can be drawn from the stories is that power relations and gender patterns on many different levels influenced the possibilities of the gender pedagogues for power and control. Power and control in the relation between technical limited rationality and care work rationality is expressed in different ways. It is seen in the possibilities and descriptions of resistance and difficulties. Resistance and difficulties depended, according to the gender pedagogues, on the differences between their own view of knowledge and that of others. If gender and gender equality was not considered to be an important area of knowledge, possibilities for power and control decreased.
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| 10. |
- Audulv, Åsa, 1980-
(författare)
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Being creative and resourceful : Individuals’ abilities and possibilities for self-management of chronic illness
- 2011
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Individuals’ self-management styles are crucial for how they manage to live with illness. Commonly investigated factors include social support, self-efficacy, health beliefs, and demographics. There is a gap in the literature with regard to in-depth studies of how those factors actually influence an individual’s self-management. The aim of this thesis was to investigate the underlying mechanisms of self-management from the perspective of individuals living with chronic illness. Interviews were conducted with 47 individuals with various chronic illnesses, some of them repeatedly over two and a half years (a total of 107 interviews). The material was analysed with; constructive grounded theory, content analysis, phenomenography, and interpretive description. The Self-management Support Model identified aspects that influenced participants’ self-management: economic and social situation, social support, views and perspectives on illness, attribution of responsibility, and ability to integrate self-management into an overall life situation. For example, individuals with a life-oriented or disease-oriented perspective on illness prioritized different aspects of self-management. People who attributed internal responsibility performed a more complex self-management regimen than individuals who attributed external responsibility. In conclusion, individuals who were creative and resourceful had a better chance of tailoring a self-management regimen that suited them well. People in more disadvantaged positions (e.g., financial strain, limited support, or severe intrusive illness) experienced difficulty in finding a method of self-management that fit their life situation. These findings can inspire healthcare providers to initiate a reflective dialogue about self-management with their patients.
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