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- Aghanavesi, Somayeh, 1981-
(författare)
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Smartphone-based Parkinson’s disease symptom assessment
- 2017
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This thesis consists of four research papers presenting a microdata analysis approach to assess and evaluate the Parkinson’s disease (PD) motor symptoms using smartphone-based systems. PD is a progressive neurological disorder that is characterized by motor symptoms. It is a complex disease that requires continuous monitoring and multidimensional symptom analysis. Both patients’ perception regarding common symptom and their motor function need to be related to the repeated and time-stamped assessment; with this, the full extent of patient’s condition could be revealed. The smartphone enables and facilitates the remote, long-term and repeated assessment of PD symptoms. Two types of collected data from smartphone were used, one during a three year, and another during one-day clinical study. The data were collected from series of tests consisting of tapping and spiral motor tests. During the second time scale data collection, along smartphone-based measurements patients were video recorded while performing standardized motor tasks according to Unified Parkinson’s disease rating scales (UPDRS).At first, the objective of this thesis was to elaborate the state of the art, sensor systems, and measures that were used to detect, assess and quantify the four cardinal and dyskinetic motor symptoms. This was done through a review study. The review showed that smartphones as the new generation of sensing devices are preferred since they are considered as part of patients’ daily accessories, they are available and they include high-resolution activity data. Smartphones can capture important measures such as forces, acceleration and radial displacements that are useful for assessing PD motor symptoms.Through the obtained insights from the review study, the second objective of this thesis was to investigate whether a combination of tapping and spiral drawing tests could be useful to quantify dexterity in PD. More specifically, the aim was to develop data-driven methods to quantify and characterize dexterity in PD. The results from this study showed that tapping and spiral drawing tests that were collected by smartphone can detect movements reasonably well related to under- and over-medication.The thesis continued by developing an Approximate Entropy (ApEn)-based method, which aimed to measure the amount of temporal irregularity during spiral drawing tests. One of the disabilities associated with PD is the impaired ability to accurately time movements. The increase in timing variability among patients when compared to healthy subjects, suggests that the Basal Ganglia (BG) has a role in interval timing. ApEn method was used to measure temporal irregularity score (TIS) which could significantly differentiate the healthy subjects and patients at different stages of the disease. This method was compared to two other methods which were used to measure the overall drawing impairment and shakiness. TIS had better reliability and responsiveness compared to the other methods. However, in contrast to other methods, the mean scores of the ApEn-based method improved significantly during a 3-year clinical study, indicating a possible impact of pathological BG oscillations in temporal control during spiral drawing tasks. In addition, due to the data collection scheme, the study was limited to have no gold standard for validating the TIS. However, the study continued to further investigate the findings using another screen resolution, new dataset, new patient groups, and for shorter term measurements. The new dataset included the clinical assessments of patients while they performed tests according to UPDRS. The results of this study confirmed the findings in the previous study. Further investigation when assessing the correlation of TIS to clinical ratings showed the amount of temporal irregularity present in the spiral drawing cannot be detected during clinical assessment since TIS is an upper limb high frequency-based measure.
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| 3. |
- Andersen, Martin, 1985-
(författare)
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Solar District Heating for Low Energy Residential Areas : A Technical Analysis of Heat Distribution Concepts for a Solar Assisted District Heating System
- 2019
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The integration of a solar thermal system into a district heating network can be a cost-effective solution, especially for new low-energy residential areas. Because of this, many new small solar district heating systems are built at the same time as the buildings, allowing for a more holistic approach to the design and construction. In doing so, it is possible to optimise the integration of the solar thermal system with respect to both cost and technical layout. This thesis presents studies that aim to investigate the most energy efficient distribution concept for successful implementation of solar district heating technology. An existing solar assisted district heating system is modelled in simulation software and the distribution system is varied in order to find out whether there is a more energy efficient option. Three system concepts are investigated: 1. A Hybrid system using a combination of high-temperature, conventional steel pipe primary culvert, intermediate substations containing solar buffer stores and a low-temperature, EPSPEX secondary culvert with DHW-circulation (so-called GRUDIS).2. A Conventional distribution system with steel pipes, higher operating temperatures and centralized solar buffer stores.3. An All GRUDIS system, using only EPSPEX distribution with DHW-circulation, lower operating temperatures and centralized solar buffer stores.A sensitivity analysis is performed by simulating the three different distribution system for various linear heat densities, with the added objective of detecting any range-bound limitations of the different distribution systems. Results indicate that both the hybrid and All GRUDIS distribution concept is preferable to conventional DH distribution regardless of the network heat density. The hybrid concept seems preferable in denser district heating networks, but results are inconclusive regarding the best concept for sparser networks. Preliminary economic considerations show that the initial investment costs may be reduced by changing from a Hybrid to an All GRUDIS distribution concept, although a more detailed analysis is needed to draw conclusions about the most economical solution.Keywords: District heating, solar thermal, simulation, renewable energy, 4DH.
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| 5. |
- Azizoğlu, Yağız, 1986-
(författare)
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Modeling of Cold Pilgering of Tubes
- 2017
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Cold pilgering is a challenging tube forming process in terms of modeling due to the complexity in kinematic of tools, friction condition and material behavior. The process development has mostly been based on simple formulas and costly full-scale tryouts. The aim in this study is to develop validated Finite element models of cold pilgering to increase the understanding of influence of the process parameters on the produced tubes.In the course of this thesis, three-dimensional mechanical and thermo-mechanical Finite element models of cold pilgering were developed. The commercial code MSC.Marc was used in the simulations. General 3D models are needed to be able to capture asymmetric deformation in cold pilgering. It was found that tool deflections together with elastic deformation of roll dies have considerable influence on the rolling force. Furthermore, the strain rate and temperature effects on the response of the material and thereby on the rolling force were evaluated.
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| 6. |
- Balaile, Gunnel
(författare)
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The Meaning of Health and Sexuality as experienced by Tanzanian Men and Women living with HIV/AIDS
- 2007
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Background: Sub-Saharan Africa has for more than two decades been hit by Human immunodeficiency virus/ Acquired immune-deficiency Syndrome, HIV/AIDS pandemic with a few signs of decline. In Tanzania, the prevalence of HIV is estimated to 7 percent and about 1.8 million Tanzanians are living with HIV. Women are the hardest hit and most vulnerable are young women 15-24 years old, who are three times more likely to be infected than young men in the same age group and the prevalence is higher in urban than in rural areas. Aim: The overall aim of this thesis was to explore the meaning of health and sexuality among men and women living with HIV/AIDS. Methods: Two studies were conducted in Tanzania, Dar es Salaam during January and February in year 2004 (I, II). Twenty participants were recruited (10 men and 10 women) by the help from health staff and sampled purposely in order to get an equal variety of age, education, religion, sex, and marital status. The interviews took place at one district hospital, and at two different clinics run by Non Governmental Organizations (NGO) one located in a business area in central town, the other NGO clinic outside town in an industrial area. The interviews were transcribed and translated into English. A phenomenological – hermeneutic approach and in-depth interviews were used to collect data. The text was ana¬lysed following Ricoeur’s interpretation theory for text. Findings: The thesis presents aspects of men’s and women’s experiences of living with HIV/AIDS. Adjustment to living with the virus was different between men and women. Men often conceived a growing suspicion that they might be in¬fected by HIV, while women had to be asked by relatives or had to wait for others to be tested. The overwhelming fear of being tested was related to the fear of being stigmatized. Under¬standing the meaning of health and sexuality when living with HIV/AIDS, was for the men living life with a preserved sense of integrity and self-esteem, this meant not to be seen as victims. To the women, however, the reality was it meant being cast into poverty and created devastation of intimate relations. Men had learnt to perform safe sex and had chosen to live with one partner/wife giving them an opportunity to develop new aspects of their intimate life. Conversely, the women felt miserable and had not accepted their diagnosis in the same way. They lacked resources to maintain health and the ability to support their children. The women who lived in a single household had abandoned sex life, their worries and deep concerns were for their children who brought meaning and joy in their lives. Conclusion: For both men and women the meaning of health and sexuality had changed after knowing their sero-status. The men had accepted to live with an altered health and treated symptoms early. The were able to handle feelings, they felt optimistic and strived to live a normal life as possible health had for the women lost meaning in that sense it was not possible to maintain. The men viewed their sex life still important, and tried to be able live a normal life. The women had accepted a life there sexuality had no place. To prevent further HIV infection meant to be educated and fully understand how to prevent the spread of HIV, to act in a responsible way, to be faithful, and/or to accept abstinence. This new way of living meant to be a caring man or woman. The use of condoms had not been completely accepted as the knowledge on how to use the condoms properly was not entirely accomplished. Support from counselors and peers were proved invaluable adjust to a life of living with HIV/AIDS.
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| 8. |
- Bastholm, Caroline, 1981-
(författare)
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Micro-grids supplied by renewable energy : Improving technical and social feasibility
- 2019
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Universal access to electricity stands high on the global agenda and is regarded as essential for positive development in sectors such as health care, education, poverty reduction, food production and climate change. Decentralized, off-grid electrification is deemed an important complement to centralized grid extension. By utilizing a renewable energy source, solar technology for the generation of electricity, photovoltaics (PV) is being considered as a way forward to minimize the environmental problems related to energy use.This thesis aims to contribute to improving the technical and social feasibility of PV and PV-diesel hybrid micro-grids for the purpose of providing access to electricity to people in rural areas of countries with low level access to electricity. In line with these general aims, the focus has been to address three questions related to challenges in three phases of rural electrification. The work has a multi-disciplinary approach, addressing mainly technical and social aspects of long-term sustainability of micro-grids, in a local context, and the changes these are intended to generate. One specific micro-grid in Tanzania has been used as a major case study.The thesis is developed through three papers, all presenting methodologies or aspects for investigation in rural electrification projects and studies in general, and for PV-diesel hybrid micro-grids in particular. Paper I puts forward a methodology to facilitate non-social scientific researchers to take social aspects increasingly into consideration. Paper II is a guideline to support system users to increasingly apply an evaluation based system operation. Paper III specifically highlights the importance to consider blackouts when investigating how an existing off-grid PV-diesel hybrid system shall be utilized when a national grid becomes available.
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| 9. |
- Berg, Mikael, 1970-
(författare)
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Historielärares historier : Ämnesbiografi och ämnesförståelse hos gymnasielärare i historia
- 2010
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The overall aim of this study is to analyse history teachers’ understanding of the school subject history. The aim have also been to uncover what factors the history teachers say have affected their understanding of the school subject. Based on survey and interview methods, the question that this study deals with is: in the light of which general understanding of the school subject history, do the teachers make didactic choices on a daily basis?The first theme is biographical. The teachers’ life-history is taken into consideration and several factors in the teachers’ background and the school environment have been identified. It also seems as if the teachers’ understanding of the school subject goes from an elementary and searching approach to one that is more complex and convinced.The second theme is a more structural approach. The results shows three major orientations among the teachers’ general understanding namely, educational (bildung) orientation, critical orientation and identity orientation. Even though a main orientation can be seen among the teachers, an important result is also that the orientation is overall complex.At the most general level some patterns can be seen. First the connection between the teachers’ biography and their general understanding of the school subject. In the understanding of the school subject, it is also notable that teachers relate in different ways to history as science, history as identity and history from an ideological viewpoint. It is also possible to note some signs of change in the school subject history that follows a lager historiographical context.
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