| 1. |
- Blumenthal, Barbara, 1969-
(författare)
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Nederbördsintensitet och andra faktorer som påverkar skyfallsskador
- 2018
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- I Sverige inträffar många skyfall och intensiva regn under sommarmånaderna. Det finns inga uppenbara geografiska mönster, vilket är en skillnad gentemot älv- eller sjööversvämningar där det vanligtvis är känt vilka områden som kan komma att översvämmas vid en viss vattennivå eller ett visst vattenflöde. För individer och samhällsaktörer innebär en skyfallshändelse i många fall en stor överraskning då skyfall utvecklas snabbt och dagens meteorologiska prognossystem i stort inte lyckas att prognosticera extrema regn korrekt med avseende på mängd, tid och plats. Vädervarningar kommer med kort varsel eller uteblir helt. Konsekvenserna av intensiv nederbörd och skyfall är främst översvämningar och erosionsskador på byggnader och infrastruktur, men även störningar och avbrott i olika samhällsfunktioner som kan påverka samhället och individer utanför det drabbade området.I denna avhandling har 15 år av försäkringsskadedata använts för att undersöka samband mellan nederbördsintensitet och skyfallsskador. Även påverkan av andra faktorer som topografi, bebyggelse och socioekonomiska aspekter har undersökts. Resultaten visar att regnintensitet under ett 60 minuters intervall i kombination med korta perioder av extrem intensitet, tillsammans med topografiska faktorer spelar en betydande roll vid uppkomsten av skador.
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| 2. |
- Christenson, Nina, 1975-
(författare)
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Knowledge, Value and Personal experience : Upper secondary students' resources of supporting reasons when arguing socioscientific issues
- 2011
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This thesis focuses on upper secondary students’ use of resources in their supporting reasons when arguing socioscientific issues (SSIs). The skills of argumentation have been emphasized in science education during the past decades and SSIs are proven a good context for learners to enhance skills of argumentation and achieve the goal of scientific literacy. Research has shown that supporting reasons from various resources are embedded in students’ argumentation on SSIs, and also that multi-perspective involvement in reasoning is important for the quality of argumentation. To explore the reasons used by students in arguing about SSIs in this thesis, the SEE-SEP model was adopted as an analytical framework. The SEE-SEP model covers the six subject areas of sociology/culture, economy, environment/ecology, science, ethics/morality and policy, which are connected to the three aspects of knowledge, value and personal experience. Two studies covering four SSIs (global warming, GMO, nuclear power and consumption) explore how students construct arguments on one SSI topic chosen by them. In paper I, I investigated students’ use of resources in their informal argumentation and to what extent students made use of knowledge. The results showed that students used value to a larger extent (67%) than knowledge (27%). I also found that the distribution of supporting reasons generated by students varied from the different SSIs. In paper II, I explored students’ use of resources in relation to students’ study background (science majors and social-science majors) and gender. The results showed that social-science majors and females generated more numbers of reasons and also showed a larger amount of multi-disciplinary resources in their supporting reasons. From the findings of this thesis, the SEE-SEP model was established as a suitable model used to analyze students’ resources of supporting reasons while arguing about SSIs. Furthermore, the potential for applying the SEE-SEP model in teachers’ SSI-teaching and students’ SSI-learning is suggested. The implications to research and teaching are also discussed.
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| 3. |
- Eriksson, Johan
(författare)
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Neuroimaging Consciousness: What happens in the brain when we become aware of what we percieve?
- 2004
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Although consciousness has been studied since the beginning of the history of psychology, how the brain implements consciousness is seen as one of the last great mysteries. This thesis investigates neural correlates of consciousness by measuring brain activity while specific contents of consciousness are defined and maintained. Study 1 showed that distinct but similar brain regions are activated for the initial creation of a percept and for sustaining that percept over time. Specifically, frontal and parietal regions were activated during both temporal aspects of consciousness. Study 2 investigated the generality of this activation pattern for consciousness in different sensory modalities, and showed that frontal regions were commonly activated for visual and auditory awareness whereas posterior activity was modality specific. However, frontal andparietal regions were jointly activated for both modalities during sustained perception. These results indicate that frontal regions interact with posterior, sensory-specific regions to instantiate a conscious percept. The percept is then maintained by a more general network including frontal and parietal regions.
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| 4. |
- Grahn, Tonje
(författare)
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A Nordic Perspective on Data Availability for Quantification of Losses due to Natural Hazards
- 2016
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Natural hazards cause enormous amounts of damage worldwide every year. Since 1994 more than 1.35 billion people have lost their lives and more than 116 million homes have been damaged. Understanding of disaster risk implies knowledge about vulnerability, capacity, exposure of persons and assets, hazard characteristics and the environment. Quantitative damage assessments are a fundamental part of disaster risk management. There are, however, substantial challenges when quantifying damage which depends on the diversity of hazards and the fact that one hazardous event can negatively impact a society in multiple ways. The overall aim of the thesis is to analyze the relationship between climate-related natural hazards and subsequent damage for the purpose of improving the prerequisite for quantitative risk assessments in the future. The thesis concentrates on two specific types of consequences due to two types of hazards, 1) damage to buildings caused by lake floods, and 2) loss of lives caused by quick clay landslides. Several causal relationships were established between risk factors and the extent of damages. Lake water levels increased the probability of structural building damage. Private damage reducing measures decreased the probability of structural building damage. Extent of damage decreased with distance to waterfront but increased with longer flood duration while prewar houses suffered lower flood damage compared to others. Concerning landslides, the number of fatalities increased when the number of humans in the exposed population increased. The main challenges to further damage estimation are data scarcity, insufficient detail level and the fact that the data are rarely systematically collected for scientific purposes. More efforts are needed to create structured, homogeneous and detailed damage databases with corresponding risk factors in order to further develop quantitative damage assessment of natural hazards in a Nordic perspective.
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| 5. |
- Marklund, Petter, 1968-
(författare)
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Shared component processes in working memory and long-term memory : Insights from functional brain imaging
- 2004
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Marklund, P. (2004). Shared component processes in working memory and long-term memory: Insights from functional brain imaging. Department of Psychology, Umeå University, S-901 87 Umeå SwedenRecent findings from functional neuroimaging studies have shown pronounced similarities in the functional brain activity patterns associated with tests of various cognitive functions. This thesis investigates shared component processes in working memory and declarative long-term memory. Study 1 showed a common pattern of increased activity in four anatomically distinct regions in prefrontal cortex during three tests each of working memory, episodic memory, and semantic memory. Such similarities may reflect shared demands on working-memory processes across all tests or increased demands on attentional mechanisms. Study 2 was designed to dissociate these possibilities by measuring sustained and transient brain activity during tests of working memory, long-term memory and sustained attention. The results provided support for the notion that one basis for overlapping activations is increased attentional demands, but some activity seems to reflect cognitive control related to mnemonic processes. Taken together, the results indicate that it is critical for taxonomies of cognitive functions to consider similarities in underlying cognitive and associated neurobiological component processes.
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| 6. |
- Nyberg, Peter, 1983-
(författare)
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Evaluation, Transformation, and Extraction of Driving Cycles and Vehicle Operations
- 2013
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- A driving cycle is a representation of how vehicles are driven and is usually represented by a set of data points of vehicle speed versus time. Driving cycles have been used to evaluate vehicles for a long time. A traditional usage of driving cycles have been in certification test procedures where the exhaust gas emissions from the vehicles need to comply with legislation. Driving cycles are now also used in product development for example to size components or to evaluate different technologies. Driving cycles can be just a repetition of measured data, be synthetically designed from engineering standpoints, be a statistically equivalent transformation of either of the two previous, or be obtained as an inverse problem e.g. obtaining driving/operation patterns. New methods that generate driving cycles and extract typical behavior from large amounts of operational data have recently been proposed. Other methods can be used for comparison of driving cycles, or to get realistic operations from measured data. This work addresses evaluation, transformation and extraction of driving cycles and vehicle operations. To be able to test a vehicle in a controlled environment, a chassis dynamometer is an option. When the vehicle is mounted, the chassis dynamometer simulates the road forces that the vehicle would experience if it would be driven on a real road. A moving base simulator is a well-established technique to evaluate driver perception of e.g. the powertrain in a vehicle, and by connecting these two simulators the fidelity can be enhanced in the moving base simulator and at the same time the mounted vehicle in the chassis dynamometer is experiencing more realistic loads. This is due to the driver's perception in the moving base simulator is close to reality. If only a driving cycle is considered in the optimization of a controller there is a risk that the controllers of vehicles are tailored to perform well in that specific driving cycle and not during real-world driving. To avoid the sub-optimization issues, the operating regions of the engine need to be excited differently. This can be attained by using a novel algorithm, which is proposed in this thesis, that alters the driving cycle while maintaining that the driving cycle tests vehicles in a similar way. This is achieved by keeping the mean tractive force constant during the process. From a manufacturers standpoint it is vital to understand how your vehicles are being used by the customers. Knowledge about the usage can be used for design of driving cycles, component sizing and configuration, during the product development process, and in control algorithms. To get a clearer picture of the usage of wheel loaders, a novel algorithm that automatically, using existing sensors only, extracts information of the customers usage, is suggested. The approach is found to be robust when evaluated on measured data from wheel loaders loading gravel and shot rock.
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| 7. |
- Persson, Erik, 1985-
(författare)
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Flood Warnings in a Risk Management Context : A Case of Swedish Municipalities
- 2015
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- As a result of the United Nations’ International Decade for Natural Disaster Reduction (1990-2000), and recent high profile disasters, disaster risk reduction has climbed high on the international political agenda. There has been a paradigm shift from reacting to disasters towards preparing for and mitigating effects of disasters. Among the measures that have been highlighted on the disaster risk reduction agenda are early warning systems. In a Swedish context, there are needs for early warnings for various flood risk types. Municipalities carry big responsibilities for managing flood risks, and early warnings have a potential to facilitate decision-making and ultimately reduce flood losses.The aim of this thesis is to describe how a variety of flood warning signals are used in the risk management process of Swedish municipalities, how they can contribute to the flood risk reducing process, and which factors influence the success of this. The thesis is based on two papers.Paper I is based on interviews with three respondents from Swedish municipalities that have invested in and established local early warning systems. The paper shows that the possible effects from a local early warning system are not only reduced flood losses but also potential spinoff, the occurrence of which is dependent on the well-being of the organisation and its risk management processes.Paper II is based on interviews with 23 respondents at 18 Swedish municipalities, who have responsibilities related to flood risk management, and one respondent who works at SMHI with hydrological warning. The paper shows that municipalities can use a variety of complementary flood warning signals to facilitate decision-making for a proactive flood response. This is however not systematically the case, and is dependent on available resources.The theoretical contribution of this thesis is a development of existing conceptual models of early warning systems with respect to risk management and system contexts, and the use of complementary warning signals.
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| 8. |
- Rydstedt Nyman, Monika, 1961-
(författare)
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Managing knowledge sharing of extreme weather induced impacts on land transport infrastructure : Case study of the Swedish Transport Administration
- 2016
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Extreme weather events and effects of climate change are threats to the transport sector’s functionality and safety. Risk management in this context implies a necessity to focus on the connection between near-term experiences and coping strategies on one hand, and long-term adaptation analyses on the other. How learning from past events and subsequent knowledge sharing can be adopted is a question that needs to be explored, discussed and tested. A systematic approach to lessons learned calls for measures of investigation, reporting, planning, implementation and evaluation. A qualitative case study approach was used in this thesis. In the first paper the practices of accident investigation in operation and maintenance were inventoried within the Swedish Transport Administration (STA). Three accident investigation methods were applied and tested on a cloudburst event, causing flooding in a railway tunnel in Sweden. In the second paper, semi-structured interviews, documents, and archival records were used as means for penetrating deeper into the attitudes and understanding of lessons learned concerning extreme weather events within a procured public-private partnership. The results of the two studies showed weak signals of feedback on lessons learned. Partly, these weak signals could be traced back to weak steering signals. Various obstacles impeded learning curves from lessons learned. The obstacles were of both hard and soft values, e.g. resources in time and equipment, systematic investigation methods, incentives for lessons learned, education and knowledge, values, norms and attitudes towards how and why identified problems should be solved. Successful knowledge sharing requires that close attention is paid to such obstacles and that an adaptive approach is adopted.
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