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  • Public defence: 2016-12-08 09:00 9C203 Nyquistsalen
    Gustavsson, Christer
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Gustavsson, Christer
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Added value from biomass by broader utilization of fuels and CHP plants2016Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The present work, where additional value-creating processes in existing combined heat and power (CHP) structures have been examined, is motivated by a political- and consumer-driven strive towards a bioeconomy and a stagnation for the existing business models in large parts of the CHP sector.

    The research is based on cases where the integration of flash pyrolysis for co-production of bio-oil, co-gasification for production of fuel gas and synthetic biofuels as well as leaching of extractable fuel components in existing CHP plants have been simulated. In particular, this work has focused on the CHP plants that utilize boilers of fluidized bed (FB) type, where the concept of coupling a separate FB reactor to the FB of the boiler forms an important basis for the analyses. In such dual fluidized bed (DFB) technology, heat is transferred from the boiler to the new rector that is operating with other fluidization media than air, thereby enabling other thermochemical processes than combustion to take place. The result of this work shows that broader operations at existing CHP plants have the potential to enable production of significant volumes of chemicals and/or fuels with high efficiency, while maintaining heat supply to external customers.

    Based on the insight that the technical preconditions for a broader operation are favourable, the motivation and ability among the incumbents in the Swedish CHP sector to participate in a transition of their operation towards a biorefinery was examined. The result of this assessment showed that the incumbents believe that a broader operation can create significant values for their own operations, the society and the environment, but that they lack both a strong motivation as well as important abilities to move into the new technological fields.

    If the concepts of broader production are widely implemented in the Swedish FB based CHP sector, this can substantially contribute in the transition towards a bioeconomy.

  • Public defence: 2016-12-09 10:15 Nyquistsalen 9C 203, Karlstad
    Nyqvist, Daniel
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Environmental and Life Sciences.
    Nyqvist, Daniel
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Environmental and Life Sciences.
    Atlantic salmon in regulated rivers: Migration, dam passage, and fish behavior2016Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Hydropower dams block migration routes and disrupt longitudinal connectivity in rivers, thereby posing a threat to migratory fish species. Various fish passage solutions have been implemented to improve connectivity with varying success. A well-functioning passage solution must ensure safe and timely passage routes that are used by a substantial portion of the migrating fish. In this thesis, I report the results from telemetry studies where the behavior and survival of migrating Atlantic salmon spawners, post-spawners and smolts have been evaluated in relation to hydropower dam passage. I evaluate downstream passage performance at dams with no passage solutions in the River Klarälven, and with simple passage solutions in in the Winooski River. In the River Ätran, I study both upstream- and downstream passage performance at a dam with sophisticated passage solutions based on the best available technology. In addition, I have studied the survival and behavior of post-spawners and hatchery-released smolts.

    A substantial portion of the spawners survived spawning and initiated downstream migration. Most males migrated downstream in autumn following spawning, whereas females tended to stay in the river until spring. For hatchery-reared smolts, early release was associated with faster initiation of migration and higher survival compared to late release. Multiple dam passage resulted in high mortality for both smolts and kelts. For smolts, dam passage, even with simple passage solutions, was associated with substantial delay and mortality. High spill levels were linked to high survival and short delay for downstream migrating salmon. The best available passage solution, which consisted of a nature-like fishway and a low sloping intake rack to guide fish to a bypass, resulted in rapid passage of a large portion of the adult migrants.

  • Public defence: 2016-12-09 13:15 11 D 227, Karlstad
    Andersson K., Pernille
    Karlstad University, Faculty of Arts and Social Sciences (starting 2013), Department of Social and Psychological Studies.
    Andersson K., Pernille
    Karlstad University, Faculty of Arts and Social Sciences (starting 2013), Department of Social and Psychological Studies.
    Changing the servicescape: The influence of music, self-disclosure and eye gaze on service encounter experience and approach-avoidance behavior2016Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The purpose of this thesis is to investigate and understand the effect of a servicescape’s ambient and social conditions on consumers’ service encounter experience and their approach/avoidance behavior in a retail context. In three papers, with a total sample of over 1600 participants (including 550 actual consumers) and seven experiments, the author investigates the effect of music (ambient stimuli), employees’ self-disclosure (verbal social stimuli) and employees’ gazing behavior (nonverbal social stimuli) on consumers’ service encounter experience and approach/avoidance behavior in a retail store.

    Paper I comprised two experiments, and the aim was to investigate the influence of music on emotions, approach/avoidance behavior. Paper II comprised two experiments, and the aim was to investigate the effect of frontline employees’ personal self-disclosure on consumers’ reciprocal behavior. Paper III comprised three experiments, and the aim was to investigate the influence of employee’s direct eye gaze/ averted eye gaze on consumer emotions, social impression of the frontline employee and encounter satisfaction in different purchase situations.

    The results in this thesis show that music affects consumers in both positive and negative ways (Paper I). Self-disclosure affects consumers negatively, in such a way that it decreases encounter satisfaction  (Paper II) and, finally, eye gaze affects consumers by regulating both positively – and in some cases also negatively – consumers’ social impression of the frontline employee and their encounter satisfaction (Paper III).

    The conclusions of this thesis are that both ambient and social stimuli in a servicescape affect consumers’ internal responses, which in turn affect their behavior. Depending on the purchase situation, type of retail, and stimuli, the internal and behavioral responses are different.

  • Public defence: 2016-12-15 13:00 Rejmersalen, 9C204, Karlstad, Sweden
    Deshpande, Raghu
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Deshpande, Raghu
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    The initial phase of sodium sulfite pulping of softwood: A comparison of different pulping options2016Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Single stage and two-stage sodium sulfite cooking were carried out on either spruce, pine or pure pine heartwood chips to investigate the influence of several process parameters on the initial phase of such a cook down to about 60 % pulp yield. The cooking experiments were carried out in the laboratory with either a lab-prepared or a mill-prepared cooking acid and the temperature and time were varied. The influences of dissolved organic and inorganic components in the cooking liquor on the final pulp composition and on the extent of side reactions were investigated. Kinetic equations were developed and the activation energies for delignification and carbohydrate dissolution were calculated using the Arrhenius equation. A better understanding of the delignification mechanisms during bisulfite and acid sulfite cooking was obtained by analyzing the lignin carbohydrate complexes (LCC) present in the pulp when different cooking conditions were used. It was found that using a mill-prepared cooking acid beneficial effect with respect to side reactions, extractives removal and higher stability in pH during the cook were observed compared to a lab-prepared cooking acid. However, no significant difference in degrees of delignification or carbohydrate degradation was seen.

     The cellulose yield was not affected in the initial phase of the cook however; temperature had an influence on the rates of both delignification and hemicellulose removal. It was also found that the  corresponding activation energies increased in the order:  xylan, glucomannan, lignin and cellulose. The cooking temperature could thus be used to control the cook to a given carbohydrate composition in the final pulp. Lignin condensation reactions were observed during acid sulfite cooking, especially at higher temperatures. The LCC studies indicated the existence of covalent bonds between lignin and hemicellulose components with respect to xylan and glucomannan. LCC in native wood showed the presence of phenyl glycosides, ϒ-esters and α-ethers; whereas the α-ethers  were affected during sulfite pulping. The existence of covalent bonds between lignin and wood polysaccharides might be the rate-limiting factor in sulfite pulping.

  • Public defence: 2016-12-16 10:00 1A305 Lagerlöfsalen
    Sandsdalen, Tuva
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Health Sciences. Högskolan i Hedmark.
    Sandsdalen, Tuva
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Health Sciences. Högskolan i Hedmark.
    Quality in palliative care from the patient perspective: Instrument development, perceptions of care received and the importance of care2016Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The overall aim was to investigate the quality of palliative care from the patient perspective, to adapt and psychometrically evaluate the Quality from Patients’ Perspective instrument specific to palliative care (QPP-PC) and investigate the relationship between the combination of person- and organization-related conditions and patients’ perceptions of care quality.

    Methods: In the systematic literature review (I), 23 studies from 6 databases and reference lists in 2014 were synthesized by integrative thematic analysis. The quantitative studies (II–IV) had cross-sectional designs including 191 patients (73% RR) from hospice inpatient care, hospice day care, palliative units in nursing homes and home care in 2013–2014. A modified version of QPP was used. Additionally, person- and organization-related conditions were assessed. Psychometric evaluation, descriptive and inferential statistics were used.

    Main findings: Patients’ preferences for palliative care included living a meaningful life and responsive healthcare personnel, care environment and organization of care (I). The QPP-PC was developed, comprising 12 factors (49 items), 3 single items and 4 dimensions: medical–technical competence, physical–technical conditions, identity–oriented approach, and socio-cultural atmosphere (II). QPP-PC measured patients’ perceived reality (PR) and subjective importance (SI) of care quality. PR differed across settings, but SI did not (III). All settings exhibited areas of strength and for improvement (II, III). Person-related conditions seemed to be related to SI, and person- and organization-related conditions to PR, explaining 18–30 and 22-29% respectively of the variance (IV).

    Conclusions: The patient perspective of care quality (SI and PR) should be integrated into daily care and improvement initiatives in palliative care. The QPP-PC can measure patients’ perceptions of care quality. Registered nurses and other healthcare personnel need awareness of person- and organization-related conditions to provide high-quality person-centred care.

  • Public defence: 2016-12-16 13:15 Fryxellsalen, 1B306
    Lindh, Magnus
    Karlstad University, Faculty of Arts and Social Sciences (starting 2013), Department of Political, Historical, Religious and Cultural Studies.
    Lindh, Magnus
    Karlstad University, Faculty of Arts and Social Sciences (starting 2013), Department of Political, Historical, Religious and Cultural Studies.
    Regionen och EU?: Uppfattningar och attityder till EU-relaterade frågor i Västsverige2016Doctoral thesis, monograph (Other academic)
    Abstract [en]

    This thesis explores perceptions and preferences on regional action in EU-related frameworks among regional actors in Western Sweden. Building upon the literature on Europeanisation and the Fusion approach, three dimensions of Europeanisation are clarified and explored– download, upload and crossload – and together with a set of five variables that constitute the Micro Fusion Framework; a comprehensive analytical tool is developed. The thesis analyses the intense debate among the members of West Sweden that took place from 2011 to 2013 that focused on how to functionally organise the regional office in Brussels in order to meet future challenges. Surprisingly, the members eventually decided to terminate their cooperation and close the jointly owned office in Brussels in spite of the fact that it has been widely regarded as successful and effective. Diverging perceptions and preferences is understood in terms of three positions on regional action; a download-, upload- and a coherent oriented position. Finally, the thesis presents the empirical findings and discusses in relation to three fusion scenarios, infusion, defusion and clustered fusion.

    In terms of Micro Fusion Framework, the dynamics shaping why West Sweden was finally regarded as a dysfunctional arena for regional action are explained by a shift of attention and action among regional actors in Western Sweden that led to pressure for further institutional adaptation in order to meet the demand of how ‘to get the best out of the EU’. Further, this redefinition of how to handle EU-affairs within the upload-oriented position was accompanied by positive attitudes towards the potential to bypass the state and thereby pursue regional priorities directly in Brussels given the compound nature of the EU. In contrast, those regional actors that are found to be more download-oriented often question the benefits of uploading activities in practice and advocate close relations to the state. A coherent oriented position recognises the importance of activities related to both of the vertical dimensions of Europeanisation.

  • Public defence: 2016-12-19 10:15 Eva Erikssonsalen, 21A342, Karlstad
    Tofique, Muhammad Waqas
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics.
    Tofique, Muhammad Waqas
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics.
    Initiation and early crack growth in VHCF of stainless steels: Experimental and theoretical analysis2016Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Mechanical fatigue is a failure phenomenon that occurs due to repeated application of mechanical loads. Very High Cycle Fatigue (VHCF) is considered as the domain of fatigue life greater than 10 million load cycles. Increasing numbers of structural components have service life in the VHCF regime, for instance in automotive and high speed train transportation, gas turbine disks, and components of paper production machinery. Safe and reliable operation of these components depends on the knowledge of their VHCF properties. In this thesis both experimental tools and theoretical modelling were utilized to develop better understanding of the VHCF phenomena.

    In the experimental part, ultrasonic fatigue testing at 20 kHz of cold rolled and hot rolled stainless steel grades was conducted and fatigue strengths in the VHCF regime were obtained. The mechanisms for fatigue crack initiation and short crack growth were investigated using electron microscopes. For the cold rolled stainless steels crack initiation and early growth occurred through the formation of the Fine Granular Area (FGA) observed on the fracture surface and in TEM observations of cross-sections. The crack growth in the FGA seems to control more than 90% of the total fatigue life. For the hot rolled duplex stainless steels fatigue crack initiation occurred due to accumulation of plastic fatigue damage at the external surface, and early crack growth proceeded through a crystallographic growth mechanism.

    Theoretical modelling of complex cracks involving kinks and branches in an elastic half-plane under static loading was carried out by using the Distributed Dislocation Dipole Technique (DDDT). The technique was implemented for 2D crack problems. Both fully open and partially closed crack cases were analyzed. The main aim of the development of the DDDT was to compute the stress intensity factors. Accuracy of 2% in the computations was attainable compared to the solutions obtained by the Finite Element Method.