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  • Public defence: 2018-06-12 13:15 Ada Lovelace, Hus B, Linköping
    Jonsson, Leif
    Linköping University, Department of Computer and Information Science. Linköping University, Faculty of Science & Engineering.
    Machine Learning-Based Bug Handling in Large-Scale Software Development2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    This thesis investigates the possibilities of automating parts of the bug handling process in large-scale software development organizations. The bug handling process is a large part of the mostly manual, and very costly, maintenance of software systems. Automating parts of this time consuming and very laborious process could save large amounts of time and effort wasted on dealing with bug reports. In this thesis we focus on two aspects of the bug handling process, bug assignment and fault localization. Bug assignment is the process of assigning a newly registered bug report to a design team or developer. Fault localization is the process of finding where in a software architecture the fault causing the bug report should be solved. The main reason these tasks are not automated is that they are considered hard to automate, requiring human expertise and creativity. This thesis examines the possi- bility of using machine learning techniques for automating at least parts of these processes. We call these automated techniques Automated Bug Assignment (ABA) and Automatic Fault Localization (AFL), respectively. We treat both of these problems as classification problems. In ABA, the classes are the design teams in the development organization. In AFL, the classes consist of the software components in the software architecture. We focus on a high level fault localization that it is suitable to integrate into the initial support flow of large software development organizations.

    The thesis consists of six papers that investigate different aspects of the AFL and ABA problems. The first two papers are empirical and exploratory in nature, examining the ABA problem using existing machine learning techniques but introducing ensembles into the ABA context. In the first paper we show that, like in many other contexts, ensembles such as the stacked generalizer (or stacking) improves classification accuracy compared to individual classifiers when evaluated using cross fold validation. The second paper thor- oughly explore many aspects such as training set size, age of bug reports and different types of evaluation of the ABA problem in the context of stacking. The second paper also expands upon the first paper in that the number of industry bug reports, roughly 50,000, from two large-scale industry software development contexts. It is still as far as we are aware, the largest study on real industry data on this topic to this date. The third and sixth papers, are theoretical, improving inference in a now classic machine learning tech- nique for topic modeling called Latent Dirichlet Allocation (LDA). We show that, unlike the currently dominating approximate approaches, we can do parallel inference in the LDA model with a mathematically correct algorithm, without sacrificing efficiency or speed. The approaches are evaluated on standard research datasets, measuring various aspects such as sampling efficiency and execution time. Paper four, also theoretical, then builds upon the LDA model and introduces a novel supervised Bayesian classification model that we call DOLDA. The DOLDA model deals with both textual content and, structured numeric, and nominal inputs in the same model. The approach is evaluated on a new data set extracted from IMDb which have the structure of containing both nominal and textual data. The model is evaluated using two approaches. First, by accuracy, using cross fold validation. Second, by comparing the simplicity of the final model with that of other approaches. In paper five we empirically study the performance, in terms of prediction accuracy, of the DOLDA model applied to the AFL problem. The DOLDA model was designed with the AFL problem in mind, since it has the exact structure of a mix of nominal and numeric inputs in combination with unstructured text. We show that our DOLDA model exhibits many nice properties, among others, interpretability, that the research community has iden- tified as missing in current models for AFL.

  • Karlsson, Olov
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Wood Science and Engineering.
    Myronycheva, Olena
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Wood Science and Engineering.
    Jones, Dennis
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Wood Science and Engineering.
    Elustondo, Diego
    Sandberg, Dick
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Wood Science and Engineering.
    Thermally modified wood treated with methacrylate2018In: Proceedings IRG Annual Meeting IRG49 Scientific Conference on Wood Protection Sandton, Johannesburg, South Africa 29 April-3 May, 2018Conference paper (Refereed)
    Abstract [en]

    Thermally modified timber (TMT)from Scots pine sapwood similar to Thermo-D quality was impregnated with methacrylate resin by the hot-and-cold method and subsequently cured at elevated temperatures. The results showedthat methacrylate resin could be used to reduce colouring of painted TMT wood during accelerated weathering probably by hindering the migration of extractives. The resin itself did not reduce greying of the unpainted wood. Hardness was only slightly improved by treatment with the resin probably due to a higher density of the material. Formation of blisters occurred but wasreduced by treatment with the resin. Resistance to mould growth by a mixture of Aureobasidium pullulans, Cladosporium cladosporioides, Aspergillus versicolor, Penicillium purpurogenumwas performed by applying EN-15457:2014. Treatment with methacrylic resin hindered the colonisation of the three last mouldfungi.

  • Kitek Kuzman, Manja
    et al.
    University of Ljubljana, Wood Science and Technology.
    Haviarova, Eva
    Purdue University, Department of Forestry and Natural Resources, West Lafayette, IN, USA.
    Sandberg, Dick
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Wood Science and Engineering.
    Collaborative housing for elderly: clever co-living concepts2018In: COST Action CA 16121 “From sharing to caring”: International interdisciplinary Seminar Socio-technical aspects of the circular and colaborative economy University Rovira i Virgili, Tarragona, 16th March, 2018, p. 51-54Conference paper (Refereed)
  • Jones, Dennis
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Wood Science and Engineering.
    Sandberg, Dick
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Wood Science and Engineering.
    Wood modification in Sweden2018In: Procedings of COST Action FP1407 WG1 and WG4 meeting.: Wood modification in Europe : processes, products, applications / [ed] Goli G and Todaro L., Florence, 2018Conference paper (Other academic)
  • Public defence: 2018-06-08 09:15 Häggsalen, Uppsala
    Helgesson, Petter
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Applied Nuclear Physics.
    Approaching well-founded comprehensive nuclear data uncertainties: Fitting imperfect models to imperfect data2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Nuclear physics has a wide range of applications; e.g., low-carbon energy production, medical treatments, and non-proliferation of nuclear weapons. Nuclear data (ND) constitute necessary input to computations needed within all these applications.

    This thesis considers uncertainties in ND and their propagation to applications such as ma- terial damage in nuclear reactors. TENDL is today the most comprehensive library of evaluated ND (a combination of experimental ND and physical models), and it contains uncertainty estimates for all nuclides it contains; however, TENDL relies on an automatized process which, so far, includes a few practical remedies which are not statistically well-founded. A longterm goal of the thesis is to provide methods which make these comprehensive uncertainties well-founded. One of the main topics of the thesis is an automatic construction of experimental covariances; at first by attempting to complete the available uncertainty information using a set of simple rules. The thesis also investigates using the distribution of the data; this yields promising results, and the two approaches may be combined in future work.

    In one of the papers underlying the thesis, there are also manual analyses of experiments, for the thermal cross sections of Ni-59 (important for material damage). Based on this, uncertainty components in the experiments are sampled, resulting in a distribution of thermal cross sections. After being combined with other types of ND in a novel way, the distribution is propagated both to an application, and to an evaluated ND file, now part of the ND library JEFF 3.3.

    The thesis also compares a set of different techniques used to fit models in ND evaluation. For example, it is quantified how sensitive different techniques are to a model defect, i.e., the inability of the model to reproduce the truth underlying the data. All techniques are affected, but techniques fitting model parameters directly (such as the primary method used for TENDL) are more sensitive to model defects. There are also advantages with these methods, such as physical consistency and the possibility to build up a framework such as that of TENDL.

    The treatment of these model defects is another main topic of the thesis. To this end, two ways of using Gaussian processes (GPs) are studied, applied to quite different situations. First, the addition of a GP to the model is used to enable the fitting of arbitrarily shaped peaks in a histogram of data. This is shown to give a substantial improvement compared to if the peaks are assumed to be Gaussian (when they are not), both using synthetic and authentic data.

    The other approach uses GPs to fit smoothly energy-dependent model parameters in an ND evaluation context. Such an approach would be relatively easy to incorporate into the TENDL framework, and ensures a certain level of physical consistency. It is used on a TALYS-like model with synthetic data, and clearly outperforms fits without the energy-dependent model parameters, showing that the method can provide a viable route to improved ND evaluation. As a proof of concept, it is also used with authentic TALYS, and with authentic data.

    To conclude, the thesis takes significant steps towards well-founded comprehensive ND un- certainties.

  • Aeby, Michael
    Graduate Institute Geneva.
    Peace and security challenges in Southern Africa: governance deficits and lacklustre regional conflict management2018Report (Other academic)
    Abstract [en]

    Armed insurgencies, social cleavages and governance deficits relating to authoritarian rule and abuse of state resources all imperil peace and stability in Southern Africa. The Southern African Development Community’s institutional framework for regional peace and security is proving ineffective because its leaders are unwilling to enforce democratic principles.

  • Public defence: 2018-06-08 09:15 Gustavianum, auditorium minus, Uppsala
    Bjersand, Kathrine
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Women's and Children's Health.
    Predictive and prognostic factors of epithelial ovarian cancer and pseudomyxoma peritonei2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The overall aim of my thesis was to investigate potential prognostic and predictive factors associated with the tumor cells of epithelial ovarian cancer (EOC) and the gastrointestinal tumor pseudomyxoma peritonei (PMP) to improve and individualize cancer therapy. Both PMP and EOC can develop into peritoneal carcinomatosis (PC), which is characterized by widespread metastasis of cancer tumors in the peritoneal cavity. Major improvements in the management of PC, such as cytoreductive surgery in combination with chemotherapy, have dramatically changed the prognosis.

    To further optimize and tailor treatment, increased knowledge on tumor biology and pathogenesis is needed. Today’s choice of treatment is mainly based on clinical trials and standard protocols that have not taken individual differences in drug sensitivity into consideration. With ex vivo testing of tumor drug sensitivity, individuals at risk of side effects only (and no treatment benefit) could potentially be identified prior to treatment.

    Napsin A is an anti-apoptotic protein that promotes platinum resistance by degradation of the cell cycle regulator and tumor suppressor TP53. Immunohistochemical stainings of 131 early EOC tumors in study I showed that expression of Napsin A was associated with expression of the apoptosis regulators p21 and p53 and with histological subtype. Positivity of Napsin A in an epithelial ovarian tumor strengthens the morphological diagnosis of clear cell carcinoma and should be useful in diagnostics. In study II, the relevance of the proteins HRNPM and SLC1A5 as prognostic factors for recurrent disease, survival and impact on clinical or pathological features was evaluated in 123 patients with early EOC. Our results support concomitant positivity of HRMPM and PUMA/p21 in ovarian cancer and indicate that HRNPM may trigger activity in systems of cell cycle regulation and apoptosis. In subgroup analyses of tumors from patients with non-serous EOC histology, expression of SLC1A5 was shown to be a prognostic factor in terms of prolonged disease-free survival. In studies III and VI, we investigated the ex vivo drug sensitivity of tumor cells from EOC and PMP with the 72-h cell viability assay fluorometric microculture cytotoxicity assay (FMCA). The two studies confirm that drug sensitivity varies considerably between tumor samples from patients within the same diagnostic group. In ovarian cancer, ex vivo results show that type I tumors were generally less sensitive to cytotoxic agents than type II tumors. Samples from patients previously exposed to cytotoxic drugs generally tended to be more resistant to most drugs than samples from unexposed patients in both EOC and PMP. This observation is in line with clinical experience and findings supporting that exposure to cytotoxic treatments contribute to development of chemo-resistance mechanisms. In ovarian cancer, resistance to the kinase inhibitors after exposure varied but was less pronounced than that for standard cytotoxic drugs. In PMP patients, ex vivo drug sensitivity provided prognostic information for progression-free survival, and this is in line with earlier findings.

  • Harvey, Nicholas C.
    et al.
    Univ Southampton, MRC Lifecourse Epidemiol Unit, Southampton SO16 6YD, Hants, England.;Univ Southampton, NIHR Southampton Biomed Res Ctr, Southampton, Hants, England.;Univ Hosp Southampton NHS Fdn Trust, Southampton, Hants, England..
    Oden, Anders
    Univ Gothenburg, Sahlgrenska Acad, CBAR, Gothenburg, Sweden.;Univ Sheffield, Ctr Metab Bone Dis, Sheffield, S Yorkshire, England..
    Orwoll, Eric
    Oregon Hlth & Sci Univ, Portland, OR 97201 USA..
    Lapidus, Jodi
    Oregon Hlth & Sci Univ, Div Biostat, Dept Publ Hlth & Prevent Med, Portland, OR 97201 USA..
    Kwok, Timothy
    Chinese Univ Hong Kong, Dept Med & Therapeut, Hong Kong, Hong Kong, Peoples R China.;Chinese Univ Hong Kong, Sch Publ Hlth, Hong Kong, Hong Kong, Peoples R China..
    Karlsson, Magnus K.
    Lund Univ, Clin & Mol Osteoporosis Res Unit, Dept Clin Sci Malmo, Malmo, Sweden.;Skane Univ Hosp, Dept Orthoped, Malmo, Sweden..
    Rosengren, Björn E.
    Lund Univ, Clin & Mol Osteoporosis Res Unit, Dept Clin Sci Malmo, Malmo, Sweden.;Skane Univ Hosp, Dept Orthoped, Malmo, Sweden..
    Ljunggren, Östen
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Endocrinology and mineral metabolism.
    Cooper, Cyrus
    Univ Southampton, MRC Lifecourse Epidemiol Unit, Southampton SO16 6YD, Hants, England.;Univ Southampton, NIHR Southampton Biomed Res Ctr, Southampton, Hants, England.;Univ Hosp Southampton NHS Fdn Trust, Southampton, Hants, England.;Univ Oxford, NIHR Oxford Biomed Res Ctr, Oxford, England..
    McCloskey, Eugene
    Univ Sheffield, Ctr Metab Bone Dis, Sheffield, S Yorkshire, England.;Univ Sheffield, Ctr Integrated Res Musculoskeletal Ageing CIMA, Mellanby Ctr Bone Res, Sheffield, S Yorkshire, England..
    Kanis, John A.
    Univ Sheffield, Ctr Metab Bone Dis, Sheffield, S Yorkshire, England.;Catholic Univ Australia, Inst Hlth & Aging, Melbourne, Vic, Australia..
    Ohlsson, Claes
    Univ Gothenburg, Sahlgrenska Acad, CBAR, Gothenburg, Sweden..
    Mellström, Dan
    Univ Gothenburg, Sahlgrenska Acad, CBAR, Gothenburg, Sweden..
    Johansson, Helena
    Univ Gothenburg, Sahlgrenska Acad, CBAR, Gothenburg, Sweden.;Univ Sheffield, Ctr Metab Bone Dis, Sheffield, S Yorkshire, England.;Catholic Univ Australia, Inst Hlth & Aging, Melbourne, Vic, Australia..
    Falls Predict Fractures Independently of FRAX Probability: A Meta-Analysis of the Osteoporotic Fractures in Men (MrOS) Study2018In: Journal of Bone and Mineral Research, ISSN 0884-0431, E-ISSN 1523-4681, Vol. 33, no 3, p. 510-516Article in journal (Refereed)
    Abstract [en]

    Although prior falls are a well-established predictor of future fracture, there is currently limited evidence regarding the specific value of falls history in fracture risk assessment relative to that of other clinical risk factors and bone mineral density (BMD) measurement. We therefore investigated, across the three Osteoporotic Fractures in Men (MrOS) Study cohorts, whether past falls predicted future fracture independently of FRAX and whether these associations varied with age and follow-up time. Elderly men were recruited from MrOS Sweden, Hong Kong, and USA. Baseline data included falls history (over the preceding 12 months), clinical risk factors, BMD at femoral neck, and calculated FRAX probabilities. An extension of Poisson regression was used to investigate the associations between falls, FRAX probability, and incident fracture, adjusting for age, time since baseline, and cohort in base models; further models were used to investigate interactions with age and follow-up time. Random-effects meta-analysis was used to synthesize the individual country associations. Information on falls and FRAX probability was available for 4365 men in USA (mean age 73.5 years; mean follow-up 10.8 years), 1823 men in Sweden (mean age 75.4 years; mean follow-up 8.7 years), and 1669 men in Hong Kong (mean age 72.4 years; mean follow-up 9.8 years). Rates of past falls were similar at 20%, 16%, and 15%, respectively. Across all cohorts, past falls predicted incident fracture at any site (hazard ratio [HR]=1.69; 95% confidence interval [CI] 1.49, 1.90), major osteoporotic fracture (MOF) (HR=1.56; 95% CI 1.33, 1.83), and hip fracture (HR=1.61; 95% CI 1.27, 2.05). Relationships between past falls and incident fracture remained robust after adjustment for FRAX probability: adjusted HR (95% CI) any fracture: 1.63 (1.45, 1.83); MOF: 1.51 (1.32, 1.73); and hip: 1.54 (1.21, 1.95). In conclusion, past falls predicted incident fracture independently of FRAX probability, confirming the potential value of falls history in fracture risk assessment.

  • Public defence: 2018-06-08 13:15 Hörsal 2, Ekonomikum, Uppsala
    Andersson, Henrik
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Social Sciences, Department of Economics.
    Immigration and the Neighborhood: Essays on the Causes and Consequences of International Migration2018Doctoral thesis, monograph (Other academic)
    Abstract [en]

    Essay 1 (with Kristoffer Jutvik): This paper uses quasi-experimental evidence to understand how changes in migration policy affect the number of asylum seekers. We look specifically at a sudden, regulatory change in the Swedish reception of Syrian asylum seekers. The change took place in September 2013, and implied that all Syrian asylum seekers would be granted permanent, instead of temporary residence permits. Using high frequency data and an interrupted time series set-up, we study the extent to which this change caused more Syrian citizens to apply for asylum in Sweden, and how the change affected the distribution of asylum seekers in Europe. Results show that the change in policy almost doubled the number of asylum seekers from Syria within 2013, with a significant jump in numbers already within the first week after the implementation of the policy. While this also decreased the share of asylum seekers to other large recipient countries (Germany), the effects were highly temporary.

    Essay 2: In this paper I estimate the causal effect of ethnic enclaves on the probability of self-employment. To account for neighborhood selection I make use of a refugee dispersal program. Results indicate that larger ethnic enclaves, measured as the share of self-employed coethnics in the municipality immigrants first arrive into, affect the probability of self-employment positively, while the share of all other coethnics has a negative effect. Results however also indicate that there is a long term economic penalty to being placed with a larger share of self-employed coethnics, an effect which is partly mediated through the choice of self-employment.

    Essay 3 (with Heléne Berg and Matz Dahlberg): In this paper we investigate the migration behavior of the native population following foreign (refugee) immigration, with a particular focus on examining whether there is any support for an ethnically based migration response. If ethnicity is the mechanism driving the change in natives' migration behavior, our maintained hypothesis is that native-born individuals who are more ethnically similar to arriving refugees should not change their migration behavior to the same extent as native-born individuals with native-born parents (who are ethnically quite different from refugees). Using rich geo-coded register data from Sweden, spanning over 20 consecutive years, we account for possible endogeneity problems  with an improved so-called ``shift-share" instrumental variable approach; in particular, our strategy combines policy-induced initial immigrant settlements with exogenous contemporaneous immigration as captured by refugee shocks. We find no evidence of neither native flight nor native avoidance when studying the full population. We do, however, find native flight among individuals who are expected to be more mobile, and within this group, we find that all natives, irrespective of their parents' foreign background, react similarly to increased immigration. Our results therefore indicate that preferences for ethnically homogeneous neighborhoods may not be the dominant channel inducing flight. Instead our estimates indicate that immigration leads to more socio-economically segregated neighborhoods. This conclusion can have important implications for the ethnically based tipping point literature.

    Essay 4 (with Matz Dahlberg): In this paper we examine the short-run housing market effects of refugee immigration to Sweden. Given that Sweden is a major refugee receiving country, it constitutes an interesting and important case to study. To deal with the endogeneity resulting from the refugees' location choices, we use an econometric specification that includes neighborhood fixed effects and an instrumental variable that is based on a historical settlement pattern mainly determined by a refugee placement policy. We find that refugee immigration to small neighborhoods has no average effect on changes in housing prices in that neighborhood. We find a positive effect on increased housing supply, measured as the number of objects on sale. The zero effect of immigration on housing prices stands in contrast to the negative results found in earlier studies. We hypothesize that the reason is due to different preferences for homogeneity in Sweden, and/or to institutional features in the Swedish rental sector.

  • Yu, Young-Sang
    et al.
    Lawrence Berkeley Natl Lab, Adv Light Source, Berkeley, CA 94720 USA.;Univ Illinois, Dept Chem, Chicago, IL 60607 USA..
    Farmand, Maryam
    Lawrence Berkeley Natl Lab, Adv Light Source, Berkeley, CA 94720 USA..
    Kim, Chunjoong
    Univ Illinois, Dept Chem, Chicago, IL 60607 USA.;Chungnam Natl Univ, Dept Mat Sci & Engn, Taejon 305764, Chungnam, South Korea..
    Liu, Yijin
    SLAC Natl Accelerator Lab, Stanford Synchrotron Radiat Lightsource, Menlo Pk, CA 94025 USA..
    Grey, Clare P.
    Univ Cambridge, Dept Chem, Lensfield Rd, Cambridge CB2 1EW, England.;SUNY Stony Brook, Dept Chem, Stony Brook, NY 11794 USA..
    Strobridge, Fiona C.
    Univ Cambridge, Dept Chem, Lensfield Rd, Cambridge CB2 1EW, England..
    Tyliszczak, Tolek
    Lawrence Berkeley Natl Lab, Adv Light Source, Berkeley, CA 94720 USA..
    Celestre, Rich
    Lawrence Berkeley Natl Lab, Adv Light Source, Berkeley, CA 94720 USA..
    Denes, Peter
    Lawrence Berkeley Natl Lab, Adv Light Source, Berkeley, CA 94720 USA..
    Joseph, John
    Lawrence Berkeley Natl Lab, Div Engn, Berkeley, CA 94720 USA..
    Krishnan, Harinarayan
    Lawrence Berkeley Natl Lab, Computat Res Div, Berkeley, CA 94720 USA..
    Maia, Filipe R.N.C.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Cell and Molecular Biology, Molecular biophysics.
    Kilcoyne, A. L. David
    Lawrence Berkeley Natl Lab, Adv Light Source, Berkeley, CA 94720 USA..
    Marchesini, Stefano
    Lawrence Berkeley Natl Lab, Adv Light Source, Berkeley, CA 94720 USA..
    Leite, Talita Perciano Costa
    Lawrence Berkeley Natl Lab, Computat Res Div, Berkeley, CA 94720 USA..
    Warwick, Tony
    Lawrence Berkeley Natl Lab, Adv Light Source, Berkeley, CA 94720 USA..
    Padmore, Howard
    Lawrence Berkeley Natl Lab, Adv Light Source, Berkeley, CA 94720 USA..
    Cabana, Jordi
    Univ Illinois, Dept Chem, Chicago, IL 60607 USA..
    Shapiro, David A.
    Lawrence Berkeley Natl Lab, Adv Light Source, Berkeley, CA 94720 USA..
    Three-dimensional localization of nanoscale battery reactions using soft X-ray tomography2018In: Nature Communications, ISSN 2041-1723, E-ISSN 2041-1723, Vol. 9, article id 921Article in journal (Refereed)
    Abstract [en]

    Battery function is determined by the efficiency and reversibility of the electrochemical phase transformations at solid electrodes. The microscopic tools available to study the chemical states of matter with the required spatial resolution and chemical specificity are intrinsically limited when studying complex architectures by their reliance on two-dimensional projections of thick material. Here, we report the development of soft X-ray ptychographic tomography, which resolves chemical states in three dimensions at 11 nm spatial resolution. We study an ensemble of nano-plates of lithium iron phosphate extracted from a battery electrode at 50% state of charge. Using a set of nanoscale tomograms, we quantify the electrochemical state and resolve phase boundaries throughout the volume of individual nanoparticles. These observations reveal multiple reaction points, intra-particle heterogeneity, and size effects that highlight the importance of multi-dimensional analytical tools in providing novel insight to the design of the next generation of high-performance devices.

  • Public defence: 2018-06-13 13:00 L111, Sundsvall
    Gustavsson, Klas
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Stochastic Modeling and Management of an Emergency Call Center: A Case Study at the Swedish Emergency CallCenter Provider, SOS Alarm Sverige AB2018Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    A key task of managing an inbound call center is in estimating its performance and consequently plan its capacity, which can be considered a complex task since several system variables are stochastic. These issues are highly crucial for certain time-sensitive services, such as emergency call services. Waiting times affect the service quality of call centers in general, but various customers may place different waiting time expectancies depending on the need. Call center managers struggle to find the relationship between these expectations to their strategical, tactical and operational issues. They are assisted by queueing models that approximate the outcome. Simple setups use analytical approximations while a network of multi-skilled agents serving several customer classes is dependent on computer simulations. Regardless of simple or complex setups, models assume that the system components are homogenous, that the components have some parametric distribution, and that they remain the same regardless of the setup. Human resource and marketing research show that such status quo assumptions are not highly reliable. As an example, customer experience is often affected by the skill of the agent, and agents themselves are affected by their workload and duties, which inter alia affect their efficiency. This thesis aim to assist the Swedish emergency call center with a strategical issue, which require detection of some causalities in the set of system components. The overall aim is to design a simulation model, but such model requires a lot of detailed system knowledge, which itself adds to the knowledge gap in the research field. Findings that contribute to the scientific knowledge body include the burst model that addresses some of the non-stationarity of call arrivals, since some rapid rate increments derives from a latent emergency event. Other contributions are the introduction of stochastic agent behavior, which increases the uncertainty in queueing models; and the service time relationship to geographical distance. The latter may involve general evidence on how area-specific understanding and cultural differences affect the quality of service. This is important for organizations that consider off-shoring or outsourcing their call center service. These findings, along with several undiscovered and unknown influencers, are needed in order to design a reliable simulation model. However, the proposed model in this study cannot be rejected, in terms of waiting time replication. This robust model allowed traffic routing strategies to be evaluated and also assisted managers of the emergency call center into a strategical shift in the late 2015.

  • Public defence: 2018-06-15 13:00 FB53, Stockholm
    Stensson, Katarina
    KTH, School of Engineering Sciences (SCI), Applied Physics.
    Generation and detection of non-classical photon states2018Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    This thesis intends to familiarize the reader with the concepts of photon statistics and correlations in quantum optics. Developing light sources that emit quantum states is central for the realization of quantum technologies. One important step in characterizing these sources is the measurement of field fluctuations and correlations, by coincidence measurements. The expectation value of a coincidence measurement, a simultaneous measurement of two intensities (or, more general, four fields), is represented by the fourth-order correlation function. The value of the correlation function, at zero delay between the detection of two photons, reveals important properties of the state to which they belonged, for example the fluctuations of the photon number. Since predictability is important for many applications, light sources emitting single photons are also characterized by the indistinguishability of consecutively emitted photons, or of two photons from separate emitters. In paper I we investigate blinking behaviour in quantum emitters, and its effect on the interference pattern and photon statistics with photons from two separate emitters. Blinking refers to an emitters transition into a non-emitting state, and subsequent transition back to an emitting state. We show that blinking can not be treated as linear loss, when measuring the fourth-order correlation function for two emitters in a Hong-Ou-Mandel setup. In general, a measurement of the fourth-order correlation function is robust to loss, which makes it a very practical tool. However, the relation between recorded coincidence counts and the correlation function is only direct in the limit of zero detection efficiency, and depends on the detection system. In paper II, we show that by adding a variable attenuation in the beam path, we can trace back to the ''true'' value of the correlation function at zero quantum efficiency. This method improves accuracy in correlation measurements by decreasing a systematic error at the expense of an increased statistical error, which is easier to handle, extending the use of coincidence methods to classical and non-classical multi-photon states.

  • Huda, Anna
    et al.
    Landeg, Fred
    Westergaard, Jørgen M.
    Exercise Pegasus 2017: Report on an African horse sickness simulation exercise conducted in 2017 and involving Denmark, Estonia, Finland, Iceland, Latvia, Lithuania, Norway and Sweden2018Book (Other academic)
    Abstract [en]

    African horse sickness (AHS) is an acute insect-borne viral disease of horses and other equines causing depression, respiratory and circulatory impairment. The mortality rate may approach 100%. The disease is transmitted by midges. In 2007–2009 midges caused the spread of bluetongue in cattle and sheep in Northern Europe. The midges are also the main vector and transmitter of AHS and the disease may occur in horses in the Nordic Baltic region during summer or early autumn. Contingency plans covering AHS have been adopted by the Nordic Baltic countries. This report provides information on the preparatory work and the conduct of a simulation exercise. The aim of the exercise included testing of National AHS contingency plans and of the communication systems established between veterinary authorities in the Nordic and Baltic countries for animal disease emergencies.

  • K. Nilsson, Annika
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Law, Department of Law.
    Hänsynsreglerna i tillsynen: Analys av hur myndigheter tillämpar och motiverar beslut gällande nyetablering av miljöfarliga verksamheter utifrån hänsynsreglerna i MB 2 kap.2018Report (Other academic)
    Abstract [sv]

    2017 utformade Naturvårdsverket detta forskningsprojekt med den övergripande frågeställningen: I vilken utsträckning bedömer och motiverar tillsynsmyndigheten sina beslut utifrån hänsynsreglerna i miljöbalken? Undersökningen avgränsades till analys av ärenden om anmälning av s.k. C-verksamheter.

    Syftet med analysen var att öka kunskaperna om hur operativa tillsynsmyndigheter tillämpar och motiverar sina beslut utifrån hänsynsreglerna, med målet att kunna använda resultaten bl. a. som underlag för att utveckla Naturvårdsverkets tillsynsvägledning.

    Undersökningen visar att tillsynsmyndigheterna ser hänsynsreglerna som centrala i deras verksamhet. Ofta men inte alltid hänvisas också till hänsynsreglerna i anmälningsärenden. I praktiken anses dock inte alltid hänsynsreglerna ändamålsenliga när tillsynsmyndigheten i sin kommunikation med verksamhetsutövarna behöver uttrycka sig konkret och tydligt. Den vägledning som efterfrågas är vägledning genom exempel på när och hur hänsynsreglerna kan tillämpas, samt gällande skälighetsavvägningar.

  • Lidin, Matthias
    et al.
    Karolinska institutet.
    Hellénius, Mai-Lis
    Karolinska institutet.
    Rydell-Karlsson, Monica
    Karolinska institutet.
    Ekblom Bak, Elin
    Swedish School of Sport and Health Sciences, GIH, Department of Sport and Health Sciences, Åstrand Laboratory of Work Physiology.
    Long-term effects on cardiovascular risk of a structured multidisciplinary lifestyle program in clinical practice.2018In: BMC Cardiovascular Disorders, ISSN 1471-2261, E-ISSN 1471-2261, Vol. 18, no 1, article id 59Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: Cardiovascular disease is still the leading cause of premature death world-wide with factors like abdominal obesity, hypertension and dyslipidemia being central risk factors in the etiology. The aim of the present study was to investigate the effects on cardiovascular risk factors and cardiovascular risk after 6 months and 1 year, in individuals with increased cardiovascular risk enrolled in a lifestyle multidisciplinary program in a clinical setting.

    METHOD: Individuals with increased cardiovascular risk were referred from primary health care and hospitals to a program at an outpatient clinic at a department of cardiology. The program consisted of three individual visits including a health check-up with a physical examination and blood sampling, and a person-centered dialogue for support in behavioural change of unhealthy lifestyle habits (at baseline, 6 months and 1 year). Furthermore, five educational group sessions were given at baseline. Cardiovascular risk was assessed according to Framingham cardiovascular risk predicting model.

    RESULTS: One hundred individuals (mean age 59 years, 64% women) enrolled between 2008 and 2014 were included in the study. Waist circumference, systolic and diastolic blood pressure and total cholesterol decreased significantly over 1 year. In parallel, cardiovascular risk according to the cardiovascular risk profile based on Framingham 10-year risk prediction model, decreased with 15%. The risk reduction was seen in both men and women, and in participants with or without previous cardiovascular disease.

    CONCLUSION: Participating in a structured lifestyle program over a year was associated with significant improvement in multiple cardiovascular risk factors and decreased overall cardiovascular risk.

    TRIAL REGISTRATION: The study is registered at www.clinicaltrials.gov (ClinicalTrial.gov ID: NCT02744157 ).

  • Halila, Leena
    et al.
    Lankinen, Veronica
    K. Nilsson, Annika
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Law, Department of Law.
    Administrativa sanktionsavgifter: En nordisk komparativ studie2018Book (Other academic)
    Abstract [sv]

    Administrativa avgiftspåföljder av straffkaraktär har under de senaste åren stått föremål för ett växande intresse och debatt i de nordiska länderna. Förevarande forskning kartlägger rättsläget gällande sanktionsavgifter i Finland samt Sverige, Norge och Danmark. I forskningen undersöks hur garantier för god förvaltning och rättvis rättegång kan säkerställas i förfaranden som gäller påförande av sanktionsavgift, samt överklagandet av dessa ärenden. I studien jämförs och analyseras dessa europarättsliga krav med de nationellrättsliga, nordiska undersökningar som utförts. Dessutom diskuteras principiella utgångspunkter som ska beaktas vid reglering av sanktionsavgifter. Forskningen har utförts av professor Leena Halila och doktorand Veronica Lankinen vid Juridiska fakulteten, Helsingfors universitet, samt universitetslektor Annika K. Nilsson, vid Juridiska fakulteten, Uppsala universitet.

  • Public defence: 2018-06-12 10:00 Kollegiesalen, stockholm
    Sui, Fangfei
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering. KTH Royal Institute of Technology.
    Fundamental models and testing of creep in copper2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Many sustainable technologies for energy production, for example, generation IV nuclear system, demand the use of materials operating at elevated temperatures for long duration of up to 60 years. Requirements that are even more stringent are found for creep exposed copper canisters for disposal of spent nuclear waste. The canisters should stay intact for thousands of years. Traditional design procedures that involve empirical extrapolation of creep data are no longer reliable for such extended times. Instead physically based material models have to be used.

    The final stage of creep before rupture, tertiary creep has been handled with empirical methods with adjustable parameters in the past, which makes it difficult to safely identify the controlling mechanisms. A physically based model has been developed for copper taking the substructure, cavitation and necking into account.

    To improve the understanding of the important contribution from particles to the creep strength an earlier formulated model has analyzed and further developed. The model has successfully been able to describe the temperature and stress dependence of precipitation hardening for copper-cobalt alloys, where this contribution totally dominates the creep strength.

    Multiaxial stress states are crucial for practically all high temperature applications. Fundamental material models have been extended for such conditions. These models have been compared with strain and stress controlled tests for notched specimens that have been performed.

  • Public defence: 2018-06-13 13:00 Hörsalen, by 117, Södertälje
    Öberg, Christian
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering. 8912104273.
    Thermal Cycling, Creep- and Tensile Testing of Cast Exhaust Materials at Elevated Temperatures2018Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    An exhaust manifold of a truck engine is subjected to tough conditions. As the truck is started, operated and shut down, it becomes subjected to thermal cycling up to around 800°C. At such high temperatures, corrosion, fatigue and creep are active degradation mechanisms. As can be imagined, the interplay between the three complicates materials selection. It is desired to have a versatile grade of high durability which is not too expensive. At the moment, a ferritic, ductile cast iron designated SiMo51 is used for the application. However, due to the rough conditions, it is considered to be on the verge of its operational limit. As a consequence, there is an ongoing search for candidate materials. In this study, the ductile cast irons SiMo51, SiMo1000, D5S and the cast steel HK30 have been included.

    In the past, there have been several studies describing corrosion and fatigue of the cast materials used for exhaust manifolds. However, on the subject of creep of cast materials, little is known. The present study aims to reveal creep tendencies of cast materials and to do it in several ways. More precisely, three creep-testing methods were employed: the conventional constant-load creep-test, the “Sequential tensile test (STT)” and “Stress relaxations with thermal cycling (SRTC)”. The first one is the traditional one. It is tedious, usually lasting months or years. The second one is a tensile test in which the strain rate is changed in sequences as specimen deformation proceeds. Here, the idea is that a slow tensile test is not different from a conventional creep test. In the third one, stress relaxations are provoked as a specimen is thermally cycled in a locked state. Since stress relaxations are a consequence of creep deformation, the relaxation data gathered from isothermal holds can be directly compared to results from the isothermal constant-load creep-test and STT. When thermally cycled in a locked state, the materials display a loop character in σ, ε and T which provides extensive information about the mechanical properties over the selected temperature interval.

    In a logarithmic Norton plot, the creep strain rate is plotted as a function of stress. By plotting STT-data in such Norton plots, it was shown that the creep behaviour of the included materials is well represented by Norton’s law. Furthermore, it was found that the creep strain rates and stress relaxations, measured during isothermal holds in SRTC, in several cases show perfect coincidence with tensile test data obtained through STT. At 700°C, data from all three tests were inserted in the same Norton plot. At higher stress levels, the SRTC-curve follows the STT-curve and at lower stresses, when the creep regime is entered, it bends down and unites with data obtained by the constant-load creep tests. Additionally, it was seen that a relatively high degree of pre-deformation can give a critical stress below which creep deformation stops completely.

  • Public defence: 2018-06-11 10:00 Ahlmannsalen, Geovetenskapens hus, Stockholm
    Mercer, Andrew
    Stockholm University, Faculty of Science, Department of Physical Geography.
    Studies in Glacier Mass Balance: Measurement and its errors2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The study of the surface mass balance of valley glaciers has a long history but one that is dogged by uncertainty and errors, and uncertainty about those errors. These problems are acknowledged by the glaciological community and have been examined and formalised in several publications. The latest of these stems from a workshop organised by the World Glacier Monitoring Service, the results of which are presented in the first paper of this thesis. The paper examines two common methods and some of their associated errors, with the aim of unifying them and providing more robust data sets. New methodologies, such as ground penetrating radar (GPR), are used in the second paper herein to provide richer and alternative data sources for approaching measurement problems related to snow depth and, to some degree, snow density. The third paper is concerned with both technical survey issues and glaciological definitions when surveys of glacier surfaces are performed for use in mass balance calculation. Many of these issues are common to remote sensing methods and ground based surveys but the paper attempts to make this commonality more explicit. Whilst the first three papers concern themselves with the act of measurement and calculation the fourth paper considers errors brought about by logistical constraints restricting the timing of surveys. Such errors are technically avoidable to a large degree but inevitable in practice. In the case presented here the error is one of unobserved accumulation, falling late in the season, after the last survey. By modelling expected ablation from minimal data, such as temperature, and comparing this with measured mass balance an estimate of unobserved accumulation is made.

    Also contained in this work is an assessment of glacier front surveys, specifically those performed by the Tarfala Research Station. Such surveys are assumed to act as a monitor of glacier response to climate change and are assumed to be a large scale proxy of mass balance but the resolution of the response as well as the resolution of survey methods indicates that the frequency of such surveys should be reduced and that remote sensing methods may be more effective.

    Common to all glaciological field surveys is the relative sparsity of data rendering error analysis and many statistical methods ineffective but new technologies such as Lidar, Global Navigation Satellite System, GPR and remote sensing indicate a way forward and the potential for future work to deliver detailed and reliable data.

  • Public defence: 2018-06-11 10:00 Gröjersalen, hus 3, Kräftriket, Stockholm
    Markowski, Peter
    Stockholm University, Faculty of Social Sciences, Stockholm Business School.
    Collaboration Routines: A Study of Interdisciplinary Healthcare2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    This thesis deals with routines for collaboration among specialists from different domains in healthcare. Healthcare policy is increasingly directed at transforming clinical healthcare into an interdisciplinary organization where diverse medical specialists collaborate in delivering complete treatments to the patient. However, as both practice and research repeatedly reports, achieving interdisciplinary collaboration is difficult. Due to the divides in knowledge and practice which exist between the medical disciplines, multidisciplinary clinics do not automatically lead to collaboration involving integration of disciplinary knowledge. Based on recent conceptualizations of organizational routines as sources of both stability and flexibility, this thesis concentrates on the type of routines that enable collaboration across domain boundaries. Collaboration routines, as they are called here, are suggested to support the interdisciplinary clinic in making use of its diversity in knowledge and practice. The thesis is comprised of four papers, including three empirical case studies of clinical healthcare. The combined findings indicate that collaboration routines support idea generation, testing of new joint practices and trial-and-error learning. Contrary to the common underlying conception of routines as blueprints, these findings bring to the surface an underlying logic of shared learning. Collaboration routines continuously support the formation and maintenance of shared cognition and shared motivation among different domain specialists, thereby assuming a function of continuous routinizing. The thesis contributes to the literature on routines by advancing research on how routines can support collaboration across domain boundaries within an organization.

  • Public defence: 2018-06-11 13:00 David Magnussonsalen (U31), Stockholm
    Dwyer, Helen
    Stockholm University, Faculty of Social Sciences, Department of Special Education.
    Children at risk Securitization theory and special education reforms2018Doctoral thesis, monograph (Other academic)
    Abstract [en]

    Special education is to a significant extent based on special education programmes and support to children who are identified as children at risk. These programmes and support are often framed in educational reforms that aim to reduce risk and barriers to equal opportunities for learning and wellbeing. This thesis sets out to explore processes of special education reforms, with a special focus on the implementation of certain reforms. Here, a theoretical framework almost unknown in special education – securitization theory – is introduced, drawing on a tradition of securitization studies within the fields of Political Science and International Relations. The Copenhagen School’s theory of securitization referred to in the thesis describes the handling of vulnerabilities, insecurities and perceived threats through the initiation and implementation of securitization processes, such as, for example, education reforms. In short, securitization theory helps us understand processes of educational reforms in terms of identified threats, such as, for example, those against equal education for a specific group of pupils. Firstly, the reforms themselves are understood as securitization projects aimed at reducing threats to the young generation and as a consequence for society.  Policies that concern children who are at risk by not receiving equal education, are handled differently among various securitization actors depending on how they perceive threats and education reform as a way to handle the perceived threat.  Secondly, I introduce a new term into the examination of securitization processes – extended securitization actor. This assists the comprehension of additional implementation procedures and turns of securitization processes in the analytical procedure. Thirdly – and here I also add to the existing securitization theory – I show how a specific reform might itself be experienced as a threat to the goals and interests of actors at the lower levels of the implementation chain, which as a consequence, produces counter securitization processes that seem to influence the implementation of the education reform. The empirical parts of the thesis consist of empirical studies from South Africa and Sweden. Discussed are those education reform policies between the mid 1940s and 1970s in South Africa and Sweden that were directed towards the indigenous populations.  Children “at risk” here concern educational issues linked to identity- and ethnic belonging and access to equal education for all children.  Another study brings up the perception of environmental threats and international claims of incorporating Education for sustainable development (ESD) into national education. Children at risk can here be understood as those exposed to environmental hazards and in exposed land areas. Still another study deals with threats concerning political and societal exclusion of ethnic and vulnerable groups. Education reform should here be seen against the historic background of former Apartheid policies and the need for democratic development with a special emphasis on teachers’ attitudes towards inclusion and perceived threats by teachers in connection with implementing inclusive education. 

  • Public defence: 2018-06-14 10:00 Kollegiesalen, Stockholm
    Tian, Ye
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering. KTH Royal institute of technology.
    Martensitic Transformation in Stainless Steels2018Doctoral thesis, comprehensive summary (Other academic)
  • Stage, Jesper
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Social Sciences.
    The Impact of Climate Policy on Environmental and Economic Performance: Evidence from Swe-den, by Rolf Färe, Shawna Grosskopf, Tommy Lundgren, Per-Olov Marklund, and Wenchao Zhou (Abingdon: Routledge, 2017), 145 pages, Hardback. ISBN 978-1-138-84747-7; eISBN 978-1-315-72680-92018In: Energy Journal, ISSN 0195-6574, E-ISSN 1944-9089, Vol. 39, no 3, p. 270-272Article, book review (Other (popular science, discussion, etc.))
  • Public defence: 2018-06-08 13:15 Häggsalen, Ångströmlaboratoriet, Uppsala
    Edwards, Samuel Charles
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Mathematics, Analysis and Probability Theory.
    Some applications of representation theory in homogeneous dynamics and automorphic functions2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    This thesis consists of an introduction and five papers in the general area of dynamics and functions on homogeneous spaces. A common feature is that representation theory plays a key role in all articles.

    Papers I-IV are concerned with the effective equidistribution of translates of pieces of subgroup orbits in quotient spaces of semisimple Lie groups by discrete subgroups. In Paper I we focus on finite-volume quotients of SL(2,C) and study the speed of equdistribution for expanding translates orbits of horospherical subgroups. Paper II also studies the effective equidistribution of translates of horospherical orbits, though now in the setting of a quotient of a general semisimple Lie group by a lattice subgroup. Like Paper II, Paper III considers effective equidistribution in quotients of general semisimple Lie groups, but now studies translates of orbits of symmetric subgroups. In all these papers we show that the translates equidistribute with the same exponential rate as for the decay of the corresponding matrix coefficients of the translating subgroup. In Paper IV we consider the effective equidistribution of translates of pieces of horospheres in infinite-volume quotients of groups SO(n,1) by geometrically finite subgroups, and improve the dependency on the spectral gap for certain known effective equidistribution results.

    In Paper V we study the Fourier coefficients of Eisenstein series for generic non-cocompact cofinite Fuchsian groups. We use Zagier's renormalization of certain divergent integrals to enable use of the so-called triple product method, and then combine this with the analytic continuation of irreducible representations of SL(2,R) due to Bernstein and Reznikov.

  • Public defence: 2018-06-14 13:15 Munin, Stockholm
    Karis, Tomas
    KTH, School of Engineering Sciences (SCI), Aeronautical and Vehicle Engineering.
    Correlation between Track Irregularities and Vehicle Dynamic Response Based on Measurements and Simulations2018Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Deviations from the design track geometry are called track irregularities, which are a main excitation mechanism in the track–vehicle dynamic system, and very important to monitor and maintain to have trac on a line run safely and comfortably. Especially during vehicle acceptance testing, it is important that a new vehicle behaves close to design predictions and within limit values, thus it is important to be able to describe track irregularities in a consistent way.

    There are several methods which quantify the eects track irregularities have on a vehicle while running along the track. Most common is analyse standard deviations and percentiles and maximum values over sections with pre-defined length. However, these quantities do not correlate well with the vehicle dynamic response, e.g. two track sections with similar maxima and standard deviations can result in very dierent response of the vehicle.

    To improve the correlation between track irregularities and vehicle re- sponse measures, it is recommended by past research to use multiple regres- sion analysis to take e.g. vehicle speed and track curvature into account as well. Other methods range from derivatives of track irregularities, via trans- fer functions and vehicle filters to neural networks. Common for all these methods are that there is either still slight inconsistencies in the results or that they are tailored for certain vehicle types on specific lines. As a result, the preferred method to evaluate track irregularities is still to use standard deviations.

    In this thesis, data from three vehicles in two measurement campaigns is evaluated using a single degree of freedom model as inspiration to break down the path from track to vehicle into several steps. A weak link in these steps is identified, which shows significantly lower correlation coecients than the other steps. The weak link is the step from vertical track irregularity second spatial derivative to vertical axle box acceleration divided by the squared vehicle speed. A variable wavelength range Dx is introduced, as an alternative to the common D1 (3–25 m), D2 (25–70 m) and D3 (70–150 m) wavelength ranges. Its wavelength range corresponds to the vehicle response band-pass filter frequencies and is thus speed dependent.

    Simulations are also carried out to investigate the weak link and for the possibility to vary parameters that cannot be changed during on-track mea- surements. A multi-body system model of the passenger coach Bim 547.5 is used, together with recorded track data and vehicle speed from the on-track measurements. The varied parameters have rather low sensitivity and aect results to a small extent. Most impact has the randomly varying vertical track stiness which aects the vertical wheel–rail forces and axle box accelerations.

    In future work, it should be explored if it is possible – and in such case how – to separate the eects of varying track stiness from the track irreg- ularities. This to better understand when a vehicle response is linked more to the track irregularities or to the track flexibility. The weak link identified in the steps from track to vehicle should also be further explored, perhaps by extending the underlying model or evaluate a dierent set of measurements.

  • Public defence: 2018-06-14 10:00 Oskar Kleins Auditorium, Stockholm
    Liu, Hao
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Protein Science, Protein Technology.
    Tumor targeted delivery of cytotoxic payloads using affibody molecules and ABD-derived affinity proteins2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Cancer treatment cost billions of dollars every year, but the mortality rate is still high. An ideal treatment is the so-called “magic bullets” that recognize and kill tumor cells while leaving normal cells untouched. In recent years, some nonimmunoglobulin alternative scaffold affinity proteins, such as affibody molecules and ADAPTs, have emerged and been used to specifically recognize different tumor antigens. In this thesis, I studied the properties and anti-tumor activities of affibody and ADAPT fusion toxins and affibody drug conjugates. In the first two papers, I studied a panel of recombinant affitoxins (affibody toxin fusion proteins) consisting of an anti-HER2 affibody molecule (ZHER2), an albumin binding domain (ABD) and a truncated version of Pseudomonas Exotoxin A(PE38X8). The affitoxins demonstrated specific anti-tumor activity on HER2-overexpressing tumor cells in vitro. A biodistribution experiment showed that addition of an ABD increased the blood retention by 28-fold and a (HE)3 N-terminal purification tag decreased hepatic uptake of the affitoxin compared with a His6 tag. In paper III, I studied immunotoxins consisting of an anti-HER2 ABD-derived affinity protein (ADAPT), an ABD and a minimized and deimmunized version of Pseudomonas exotoxin A (PE25). These immunotoxins demonstrated potent and specific cytotoxicity toward HER2 overexpressing tumor cells in vitro similar to affitoxins. In paper IV, I produced a panel of affibody drug conjugates consisting of ZHER2, ABD and malemidocaproylmertansine (mc-DM1). The conjugates had selective toxic activity on HER2-overexpressing tumor cells in vitro comparable with the approved drug trastuzumab emtansine. The conjugate, ZHER2-ZHER2-ABD-mc-DM1 was found to prolong the life span of tumor bearing mice and delayed the growth ofxenografted SKOV-3 tumors. In conclusion, affibody molecules and ADAPTs are promising alternatives to antibodies for targeted tumor therapy.

  • Public defence: 2018-06-08 10:00 Lilla hörsalen, KB.E3.01, Umeå
    Chrobok, Daria
    Umeå University, Faculty of Science and Technology, Department of Plant Physiology. Umeå University, Faculty of Science and Technology, Umeå Plant Science Centre (UPSC).
    To “leaf” or not to “leaf”: Understanding the metabolic adjustments associated with leaf senescence2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The adequate execution of the final developmental stage of a leaf, leaf senescence, is crucial to the long-term survival of the plant. During senescence cellular structures like membranes, proteins, lipids and macromolecules are degraded and released nutrients are relocated to developing parts of the plant, such as young leaves, stems, flowers, siliques and ultimately seeds that are dependent on this nutrient remobilization. The first visible sign of senescence is the yellowing of leaves indicating the degradation of chlorophyll and the dismantling of chloroplasts. As a consequence, senescing leaves cannot perform photosynthesis anymore and the delivery of energy from the chloroplast is compromised. As chloroplasts lose their function, the course of the senescence program requires a stable alternative energy sources that support nutrient remobilization while simultaneously ensuring a basic metabolism.

    To study leaf senescence I used the model plant Arabidopsis thaliana and applied different experimental approaches: Developmental Leaf Senescence (DLS), individual darkened leaves (IDL), completely darkened plants (DP) and a stay-green mutant which displays a delayed senescence phenotype during IDL. Using a combination of physiological, microscopic, transcriptomic and metabolomic analyses similarities and differences between these experimental setups were investigated with focus on the functions of mitochondria during leaf senescence.

    The catabolism of amino acids and the subsequent release of glutamate into the mitochondrial matrix seem to play an important role for nitrogen remobilization during DLS and IDL. Glutamate is then transported to the cytoplasm and transformed into glutamine, which can serve as long distance nitrogen export metabolite in the plant. Furthermore, senescing leaves in IDL are not only source tissues for nutrient remobilization in the plant, but we also detected labelled carbon in the darkened leaves, indicating a communication between the IDL and leaves in light. In contrary to the senescence inducing systems of DLS and IDL, in DP and the stay-green mutant investigated here, senescence is not induced by dark treatment. In both experimental setups we measured an accumulation of amino acids in the darkened leaves, in particular those with high N content. This could make reduced carbon available as alternative energy source during darkness. In this thesis we observed that mitochondria play an important role in nutrient reallocation processes during leaf senescence. The overall energy status of senescing tissues depends on mitochondria and especially amino acid metabolism seems to have a vital role during the senescence processes both for energy supply and nutrient reallocation.

  • Abbas, Nahla
    et al.
    School of Engineering & Technology, Central Queensland University, Melbourne.
    Wasimi, Saleh
    School of Engineering & Technology, Central Queensland University, Melbourne.
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Sultana, Nasrin
    RMIT University, Melbourne.
    Water resources problems of Iraq: Climate change adaptation and mitigation2018In: Journal of Environmental Hydrology, ISSN 1058-3912, E-ISSN 1996-7918, Vol. 26, article id 6Article in journal (Refereed)
    Abstract [en]

    Iraq is suffering from water scarcity, and future predictions indicate that it could get worse due to changing climate. Arguably, climate change is one of the greatest challenges onfronting this region it could have significant adverse effects on water resources and hence the environment and economy, particularly in the agricultural sector. This study considers possible adaptation and mitigation measures that could be undertaken in response to climate change. To overcome this problem,adaptation measures at farm and government level were conferred. Farm-level adaptation comprises adopting crop modification, soil conservation, irrigation, changing crop calendar and planting of trees. The government role is to ensure success of these adaptation measures. The government should get involved and support the farmers financially and technologically.

  • Eklund, Patrik
    et al.
    Umeå University, Faculty of Science and Technology, Department of Computing Science.
    Kortelainen, Jari
    Two approaches to System-of-Systems from Lative Logic point of view2017In: 6TH INTERNATIONAL YOUNG SCIENTIST CONFERENCE ON COMPUTATIONAL SCIENCE, YSC 2017 / [ed] Klimova, A Bilyatdinova, A Kortelainen, J Boukhanovsky, A, Elsevier, 2017, Vol. 119, p. 16-21Conference paper (Refereed)
    Abstract [en]

    The paper presents two approaches to model System-of-Systems on lative logic point of view. Lative logic is a general framework to construct building blocks of logic using Category Theory as its metalanguage. This approach reveals avenues to describe System of -Systems themselves, and to model information and processes they posers, using some reasonable modelling languages in a computational manner, thus, touching foundations of computational science. After presenting some preliminary notes, the paper explains the main steps to construct lative logics, and then give two approaches to System-of-System modelling. Finally, the paper presents a survey to some applications.

  • Public defence: 2018-06-08 13:15 B1014, Jönköping
    Kaneberg, Elvira
    Jönköping University, Jönköping International Business School, JIBS, Business Administration. Jönköping University, Jönköping International Business School, JIBS, Centre of Logistics and Supply Chain Management (CeLS).
    Emergency preparedness management and civil defence in Sweden: An all-hazards approach for developed countries' supply chains2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    This thesis addresses the evolving role of supply chain networks in the structures of the emergency preparedness planning. The thesis focuses on the management of planning in emergency preparedness and civil defence in Sweden. Various levels of planning are combined with insights from business and network theories to understand how the civil society actors involved meet demands imposed by complex emergencies and changing threats to civil society. Empirically, the study is based on five case studies that primarily use interviews and secondary materials from observations, documents and research. The combined findings and analyses of the embedded case studies are integrated into a conceptual whole (called kappa) that explains how the roles and relations of actors in emergency planning need to develop over time. The most important finding of this study is that civil society in developed countries must be organised in a completely different way than today to meet the changing demands. The all-hazards approach to planning offers civil society actors a rationale for entering into different networks. The supply chain networks can provide structure to the different types of planning. Moreover, this study shows that civil society actors have strategic capabilities for meeting threats, but these should be addressed in roles and tasks for the safety and security readiness. This capability can be achieved at different levels of planning (tactical, operational, strategic) and in different relations (civil, commercial, military, voluntary), which explains the significant differences between the emergency preparedness management in different response operations. It is suggested that a lack of political willingness or policy readiness to all-hazards planning provides substantial choices in interpreting the role and task of the emergency preparedness management system, through which supply chains networks mainly become a contextualized condition. Two underlying preparedness views are identified that contribute to the planning of actors and their relations when involved in the Swedish safety and security readiness. The civil defence planning for developing civil military relations is considered in networks for structuring, managing and coordinating these relations, on the one hand. The emergency preparedness and all-hazards approach planning, for managing the commercial, voluntary and individual relations, and for delimiting the networks into manageable nets, on the other hand. This thesis contributes to the current understanding of emergency preparedness management and civil defence planning using an all-hazards-planning strategy as objective instead of a fragmented planning objective (in separated systems). This understanding is linked to the evolving role of the supply chain network as the solution to the urgent need of structure of the fragmented preparedness planning to meet the increasingly changing demands. An all-hazards-planning approach helps to describe the managing and planning structures and how supply chain networks need to develop into the preparedness systems as delimited structures over time. Moreover, this thesis contributes to the emergency planning literature by paying attention to a different type of planning for safety and security in two ways: first, by specifying what essential capabilities of civil society actors are linked to the operationalisation of planning; second, by providing insights into civil military coordination along networks over time. Rather than defining the essential differences between actors in the networks, including the military and civil actors (which refers to public authorities and the commercial and voluntary sectors in Sweden), this thesis suggests that civil-military relations public-private collaboration and voluntary involvement in the supply chain network are essential capabilities for any developed country to deal with the risky availability of essential resources. By showing how this different preparedness planning is described and located over time, this thesis discusses emergency preparedness and network theory, all-hazards planning, applicability to other developed countries, safety and security strategies, and the relations among civil society actors to examine the dimensions in supply chain network structures that can support the planning.

     

  • Beckman, Claes
    et al.
    KTH, School of Information and Communication Technology (ICT), Centres, Center for Wireless Systems, Wireless@kth. KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS.
    Lindmark, Björn
    Ahl´berg, Mikael
    Dual Band Base Station Antenna Systems1998In: Broad Band Radio Access, Linköping, 1998, p. 69-74, article id 9Conference paper (Other academic)
    Abstract [en]

    An analysis of the possibilities of using dualband antennas in cellular radio is presented. Results from simultaneous measurements at 900 MHz and 1800 MHz are presented and analyzed. Based on the measured results, a dual polarized, dual band base station antenna has been designed. Such an antenna proveides the opportunity to replace a 4 antenna space diversity installation with a single antenna, thereby reducing costs and tower space.

  • Mejtoft, Thomas
    et al.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Söderström, Ulrik
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Intressentfokuserade oberoende longitudinella utvärderingar2018In: Proceedings från 6:e Utvecklingskonferensen för Sveriges ingenjörsutbildningar / [ed] Lena Peterson, Kristina Edström, Oskar Gedda, Fredrik Georgsson, Liselott Lycke och Marie Arehag, Göteborg: Chalmers tekniska högskola , 2018, p. 94-96Conference paper (Refereed)
    Abstract [sv]

    Utbildningskvalité är en mycket viktig fråga som diskuteras frekvent inom universitetsvärlden. Såväl kontroll som förbättring av utbildningskvalité är i många lägen starkt kopplat till olika former av utvärderingar. Denna artikel syftar till att illustrera och analysera en utvärderingsmodell som har använts på ett civilingenjörsprogram vid Umeå universitet. Målsättningen med utvärderingsmodellen är att skapa mer holistiska utvärderingar med ett starkare fokus på de intressenter som finns för kvalitetsutveckling - studenter och lärare.

  • Public defence: 2018-06-13 10:00 B1014, Jönköping
    Habimana, Olivier
    Jönköping University, Jönköping International Business School, JIBS, Economics.
    Asymmetry and multiscale dynamics in macroeconomic time series analysis2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    This thesis consists of three independent articles preceded by an introductory chapter. The first two articles focus on exchange rate dynamics in emerging market and developing economies, taking into account nonlinearities and asymmetries which are relevant for these countries and are potentially due to (i) transaction costs and other market frictions, and (ii) official intervention in the foreign exchange market. The third article is devoted to the analysis of the effects of monetary policy at different time horizons.

    The first article evaluates the purchasing power parity (PPP) theory in a panel of Sub-Saharan African countries. Unit root tests that are based on exponential smooth transition autoregressive (ESTAR) models are applied to account for nonlinearities and asymmetries in real exchange rate adjustment towards its equilibrium (mean) value. The results indicate empirical support for the PPP theory.

    The second article examines the relationship between current account adjustment and exchange rate flexibility in a panel of emerging market and developing economies. The purpose of this article is to (i) obtain a measure of exchange rate flexibility that considers autoregressive conditional heteroscedasticity and possible asymmetric responses of the exchange rate to shocks, and (ii) apply suitable dynamic panel data estimators to investigate this relationship. The results indicate that more flexible exchange rates are associated with faster current account adjustment.

    By means of wavelets the third article investigates the liquidity effect and the long-run neutrality of money at detailed timescales using time series data for Sweden and the US. The results indicate a significant liquidity effect at horizons of one to four years, but there is no evidence of monetary neutrality.

  • Östling, Robert
    et al.
    Stockholm University, Faculty of Humanities, Department of Linguistics, Computational Linguistics.
    Börstell, Carl
    Stockholm University, Faculty of Humanities, Department of Linguistics, General Linguistics. Radboud University, Netherlands.
    Courtaux, Servane
    École Nationale Supérieure de Techniques Avancées, ParisTech, Paris, France.
    Visual Iconicity Across Sign Languages: Large-Scale Automated Video Analysis of Iconic Articulators and Locations2018In: Frontiers in Psychology, ISSN 1664-1078, E-ISSN 1664-1078, Vol. 9, article id 725Article in journal (Refereed)
    Abstract [en]

    We use automatic processing of 120,000 sign videos in 31 different sign languages to show a cross-linguistic pattern for two types of iconic form–meaning relationships in the visual modality. First, we demonstrate that the degree of inherent plurality of concepts, based on individual ratings by non-signers, strongly correlates with the number of hands used in the sign forms encoding the same concepts across sign languages. Second, we show that certain concepts are iconically articulated around specific parts of the body, as predicted by the associational intuitions by non-signers. The implications of our results are both theoretical and methodological. With regard to theoretical implications, we corroborate previous research by demonstrating and quantifying, using a much larger material than previously available, the iconic nature of languages in the visual modality. As for the methodological implications, we show how automatic methods are, in fact, useful for performing large-scale analysis of sign language data, to a high level of accuracy, as indicated by our manual error analysis.

  • Public defence: 2018-06-09 09:15 Auditorium Minus, Uppsala
    Cocco, Arianna
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Neuroscience, Physiology.
    The γ-aminobutyric acid and proton signaling systems in the zebrafish brain: Characterization and effect of stress2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The central nervous system of vertebrates is continuously processing sensory information relayed from the periphery, integrating it and producing outputs transmitted to efferents. In the brain, neurons employ an array of messenger molecules to filter afferent information and finely regulate synaptic transmission. The γ-aminobutyric acid (GABA) is the major inhibitory neurotransmitter in the adult vertebrate central nervous system, synthesized from α, L-glutamate by the glutamate decarboxylases (GADs). GABA promotes fast hyperpolarization of target cells mediated by the ionotropic, chloride-conducting type A GABA (GABAA) receptors. Those channels are homo- or heteropentamers and, in the zebrafish, at least twenty-three genes encode for putative GABAA receptor subunits.

    The present PhD thesis presents the expression levels of the almost complete panel of the GABA signaling machinery in the adult zebrafish brain and retinas. The results point toward GABA signaling modalities in zebrafish strikingly similar to those observed in mammals. The most common GABAA receptor subunit combinations in the whole brain were proposed to be α1β2γ2 and α1β2δ, and region-specific GABAA channels were also inferred. Those included telencephalic α2bβ3γ2, α2bβ3δ, α5β2γ2, α5β3γ2 and cerebellar α4β2γ2 and α4β2δ. A tissue specific expression was documented for the paralogues α6a and α6b; the former was abundantly transcribed in the retinas, the latter in the cerebellum. Proposed retinal GABAA receptors were α1βxγ2, α1βxδ, α6aβxγ2 and α6aβxδ, with either β2 or β3.

    Focus was also placed on functional aspects of the GABA signaling system in the adult zebrafish brain, and specifically on the effects of stress on GABAA receptor subunits expression. Treated animals experienced social isolation and repeated confinement, and depicted increased mRNA levels of several GABAA receptor monomers. It was deduced that a higher number of extrasynaptic, tonic-current-mediating GABAA channels was synthesized in the brain following stress. As synaptic transmission promotes extracellular acidification, interest was also placed on the acid-sensing ion channel (ASIC) subunits. The overall results presented in this PhD thesis point toward GABA and proton signaling systems in the zebrafish brain that have many common points with those of mammals. Thus, fundamental signaling pathways appear to be conserved across vertebrates.

  • Public defence: 2018-06-09 10:15 Humanistiska teatern, Uppsala
    Shao, Yan
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Languages, Department of Linguistics and Philology.
    Segmenting and Tagging Text with Neural Networks2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Segmentation and tagging of text are important preprocessing steps for higher-level natural language processing tasks. In this thesis, we apply a sequence labelling framework based on neural networks to various segmentation and tagging tasks, including sentence segmentation, word segmentation, morpheme segmentation, joint word segmentation and part-of-speech tagging, and named entity transliteration. We apply a general neural CRF model to different tasks by designing specific tag sets. In addition, we explore effective ways of representing input characters, such as utilising concatenated n-grams and sub-character features, and use ensemble decoding to mitigate the effects of random parameter initialisation.

    The segmentation and tagging models are evaluated in a truly multilingual setup with more than 70 datasets. The experimental results indicate that the proposed neural CRF model is effective for segmentation and tagging in general as state-of-the-art accuracies are achieved on datasets in different languages, genres, and annotation schemes for various tasks. For word segmentation, we propose several typological factors to statistically characterise the difficulties posed by different languages and writing systems. Based on this analysis, we apply language-specific settings to the segmentation system for higher accuracy. Our system achieves substantially better results on languages that are more difficult to segment when compared to previous work. Moreover, we investigate conventionally adopted evaluation metrics for segmentation tasks. We propose that precision should be excluded and using recall alone is more adequate for sentence segmentation and word segmentation. The segmentation and tagging tools implemented along with this thesis are publicly available as experimental frameworks for future development as well as preprocessing tools for higher-level NLP tasks.

  • Chandolias, Konstantinos
    et al.
    University of Borås, Faculty of Textiles, Engineering and Business.
    Wainaina, Steven
    Niklasson, Claes
    Chalmers Technical University.
    Taherzadeh, Mohammad J
    University of Borås, Faculty of Textiles, Engineering and Business.
    Effects of Heavy Metals and pH on the Conversion of Biomass to Hydrogen via Syngas Fermentation2018In: BioResources, ISSN 1930-2126, E-ISSN 1930-2126Article in journal (Refereed)
    Abstract [en]

    The effects of three heavy metals on hydrogen production via syngas fermentation were investigated within a metal concentration range of 0-1.5 mg Cu/L, 0-9 mg Zn/L, 0-42 mg Mn/L, in media with initial pH of 5, 6 and 7, at 55 °C. The results showed that at lower metal concentration, pH 6 was optimum while at higher metal concentrations, pH 5 stimulated the process. More specifically, the highest hydrogen production activity recorded was 155.28% ± 12.02% at a metal concentration of 0.04 mg Cu/L, 0.25 mg Zn/L, and 1.06 mg Mn/L and an initial medium pH of 6. At higher metal concentration (0.625 mg Cu/L, 3.75 mg Zn/L, and 17.5 mg Mn/L), only pH 5 was stimulating for the cells. The results show that the addition of heavy metals, contained in gasification-derived ash, can improve the production rate and yield of fermentative hydrogen. This could lead in lower costs in gasification process and fermentative hydrogen production and less demand for syngas cleaning before syngas fermentation.

  • Public defence: 2018-06-05 10:15 F104, Trollhättan
    Mahade, Satyapal
    University West, Department of Engineering Science, Division of Subtractive and Additive Manufacturing.
    Functional Performance of Gadolinium Zirconate/Yttria Stabilized Zirconia Multi-Layered Thermal Barrier Coatings2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Yttria stabilized zirconia (YSZ) is the state-of-the-art ceramic top coat material used for thermal barrier coating (TBC) applications. Demand for higher efficiency in gas turbine engines has led to a continuous increase in the gas in let temperature. However, this increase in temperature has pushed YSZ to its upper limit. Above1200 °C, issues such as poor phase stability, high sintering rate, and susceptibility to CMAS (Calcium Magnesium Alumino Silicates) degradation limit the durability of YSZ based TBCs. Among the new top coat materials suggested for high temperature TBC applications, gadolinium zirconate (GZ) is an interesting alternative to YSZ since it has shown attractive properties which include a better resistance to CMAS attack. However, GZ has poor thermo-chemical compatibility with the thermally grown oxide (alumina), leading to poor thermalcyclic fatigue performance of single layered GZ TBCs. Therefore, a multi-layered GZ/YSZ based TBC design seems promising. This work presents a new approach of depositing multi-layered (double and triple layered) GZ/YSZ TBCs using the recently developed suspension plasma spray(SPS) process. SPS was employed in this work because of its capability to mimic the electron beam physical vapour deposition (EB-PVD) process in terms of producing columnar microstructured TBCs. Single layer YSZ TBCs were also deposited by SPS process and used as a reference for comparing the functional performance of multi-layered GZ based TBCs. The primary aim of this work was to improve the durability of GZ based multilayered TBCs at high temperatures. Durability tests were performed in the temperature range 1100 °C - 1400 °C under different thermal cyclic test conditions (with and without thermal gradient). The results indicate that multilayered GZ based TBCs improve durability compared to the single layer YSZTBCs at all the test temperatures. Failure analysis of the multi-layered GZ/YSZTBCs revealed spallation within the GZ layer close to GZ/YSZ interface and the reason was believed to be the inferior fracture toughness of GZ. In order to improve the fracture toughness in the region of failure, a composite approach comprising multi-layered GZ+YSZ based TBC was considered. It was shown that the composite GZ+YSZ based TBCs did not improve the thermal cyclic lifetime, although improvement in fracture toughness was observed. As a further extension of this work, the influence of YSZ layer thickness on the durability of GZ/YSZTBCs was investigated. It was shown that an increase in YSZ layer thickness in the GZ/YSZ TBC led to poor durability. Additionally, the other important performance criteria for TBCs, i.e. thermal conductivity, was measured experimentally and compared with the single layer YSZ TBC. It was shown that the GZ based TBCs had lower thermal conductivity than YSZ. The second aim was to investigate and compare the erosion performance of multi-layered GZ based TBCs and single layered YSZ TBCs. In the erosion testconducted at room temperature, the GZ based TBCs showed lower erosion resistance compared to the single layer YSZ TBC. The main reason for this difference was attributed to the inferior fracture toughness of GZ. In case of the composite multi-layered GZ+YSZ based TBC, an improvement in erosion resistance was observed compared to the multi-layered GZ based TBC. Based on the results obtained, this work has demonstrated that SPS is a promising processing technique to produce columnar microstructured TBCs irrespective of the composition (GZ, YSZ, GZ+YSZ). It was also shown that GZ/YSZ multilayered TBCs are promising for high temperature TBC applications due to theirl ow thermal conductivity and high thermal cyclic fatigue lifetime. However, low erosion resistance for certain applications might be an issue for the GZ basedTBCs.

  • Public defence: 2018-06-07 09:15 Auditorium Minus, Uppsala
    Löscher, Andreas
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Computer Systems. Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Division of Computing Science.
    Targeted Property-Based Testing with Applications in Sensor Networks2018Doctoral thesis, monograph (Other academic)
    Abstract [en]

    Testing is a fundamental part of modern software development, as it unveils bugs in the system under test and gives confidence in their correctness. Testing is often a laborious task as it typically requires to write by hand a plethora of test cases to test a system thoroughly. This task can be aided by high-level testing techniques such as random property-based testing (PBT) where the testing task is reduced to specifying properties that the system under test is expected to satisfy, and generators that produce well-distributed random inputs to these properties. However, as with all random testing techniques, the confidence in the system and the chances of finding a bug is proportional to the number of tests. If the set of possible inputs is large, even a high number of tests does not yield a satisfactory result. One example is testing sensor networks, where one not only needs to produce the inputs for the software system but also needs to consider the network topology and the systems environment.

    This dissertation presents targeted property-based testing, an enhanced form of PBT where the input generation is guided by a search strategy instead of being random, thereby combining the strengths of QuickCheck-like and search-based testing techniques. It furthermore presents an automation for the simulated annealing search strategy that reduces the manual task of using targeted PBT. We present concrete implementations for all presented techniques and a framework for PBT of sensor networks.

    Applying PBT to testing sensor networks has allowed us to test relatively complex software and uncover subtle and hard-to-find bugs. We evaluate targeted PBT by comparing it to its random counterpart on a series of case studies. We show that its testing performance is significantly higher than that of random PBT. Furthermore, we demonstrate that the extra effort required to use targeted PBT is limited to specifying a test goal. With these results, we argue that targeted PBT improves the state-of-the-art of software testing and ultimately leads to higher confidence in complex software systems.

  • Public defence: 2018-06-07 10:15 Room 13:026, Uppsala
    Guath, Mona
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Social Sciences, Department of Psychology.
    Feedback learning and multiple goal pursuit in an electricity consumption task2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The overall aim with the thesis was to investigate how learning to pursue two conflicting goals (cost and utility) in an electricity consumption task is affected by different forms of feedback, goal phrasing, and task environment. Applied research investigating the efficiency of outcome feedback on electricity consumption via in-home displays points at modest reductions (2-4%). Further, a wealth of cognitive psychological research shows that learning with outcome feedback is not unproblematic. A new experimental paradigm, the simulated household, that captures the cognitive task that confronts people when trying to regulate their electricity consumption, was developed. In three studies, different aspects of the problem of regulating one’s consumption was investigated. Study I, investigated how different feedback in terms of frequency, detail, and presence of random noise or not affect performance. It also investigated if participants pursued the goals sequentially or simultaneously and if they were able to derive a model of the task. Results showed that frequent feedback was beneficial only in a deterministic system and, surprisingly, random noise improved performance by highlighting the most costly appliances. Modelling results indicated that participants pursued goals sequentially and did not have a mental model of the task. Study II, investigated if a short feedforward training could replace or complement outcome feedback. Results indicated that the performance with one of the feedforward training schemes lead to comparable performance to outcome feedback only. The best performance was obtained when this feedforward scheme was combined with outcome feedback. Study III, investigated if the sequential goal pursuit observed in Study I was related to interpretation of the task or cognitive limitations by specifying goals for cost and/or utility. Further, it investigated the reason for the cost prioritisation. Results indicated that the sequential goal pursuit derives from cognitive constraints. Together, the results from the studies suggest that people pursue the goals sequentially and that instant outcome feedback may harm performance by distracting people from the most important and costly appliances to the appliances that allow large variability in use.

  • Public defence: 2018-06-01 10:00 Kalmar
    Davidsson, Marita
    Linnaeus University, Faculty of Social Sciences, Department of pedagogy.
    Värdeladdade utvärderingar: en diskursanalys av förskolors systematiska kvalitetsarbete2018Licentiate thesis, monograph (Other academic)
    Abstract [en]

    The overarching interest of this licentiate thesis is directed towards values as they are discursively constructed in systematic quality work in preschool. The aim of the study is to contribute with knowledge about the values discursively expressed in systematic quality work in preschool and how these can, in turn, be understood in relation to current quality work contexts. Values, as understood in the study, are assumptions about something good, desirable and worth aiming at and are seen as socially constructed in a specific societal, cultural and historical context. Discourse can be interpreted as a certain way of talking about and understanding values where language represents a specific meaning context.

    Fairclough’s critical discourse analysis has been applied to critically examine and make visible what values and discourses are expressed in the systematic quality work in preschool, as well as their mutual relations. In addition, Ball’s performativity concept has been used. The empirical material consists of 17 preschools’ documented systematic quality work in the form of evaluations conducted during the 2014-2015 school year.

    The value practice emerging from the analysis of the evaluations carries a complexity in that values appear to overlap and may thus be hard to separate. Values are both explicitly and implicitly expressed. What is highlighted as desirable can be categorized within five areas: competence, democracy, ethics, disciplination and efficiency.

    The result shows that a goal rational, a market-oriented, a relational, a morally oriented and a development psychology discourse are included in the order of discourse that exercises power over the values that are expressible and over the way this is done. The analysis clearly demonstrates the predominance of the goal rational discourse, while the influence of the development psychology discourse seems to be limited with regard to what is considered desirable in the organization. It also emerges that there is a power structure where the goal rational and the market-oriented discourses seem to include and articulate the other discourses within the order of discourse.

    In a long-time perspective, preschool activities appear to have passed from development psychology rationality to goal rationality. For preschool children this transformation may have entailed that currently the strongly emphasized welfare aspect of the organization tends towards a strong emphasis on competence. These values stand out in the evaluations as two opposite poles, which may indicate a swing of the pendulum from one side to the other.

  • Public defence: 2018-06-13 10:00 Q2, Stockholm
    Gaborit, Mathieu
    KTH, School of Engineering Sciences (SCI), Aeronautical and Vehicle Engineering, Marcus Wallenberg Laboratory MWL. LAUM UMR CNRS 6613, Le Mans Université, Le Mans, France.
    Modelling of thin and imperfect interfaces: Tools and preliminary study2018Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    For quite some time, the strive for more efficient acoustic absorbers keepsincreasing, driven by a number of psycho-physiological studies on health re-lated dangers of noise exposure. As the global wealth increases and with itthe global expectation of quieter living and working environments, manifestedin both politics and research, an important market for sound absorbing andnoise control systems develops in all industrialised countries. In the acousticcommunity, the main endeavours of the two last decades have been orientedtowards a better understanding of the dissipation phenomena in absorbers(and especially in poroelastic media) as well as proposing new topologies andstructures for these elements. These efforts have resulted in an abundant lit-erature and numerous improvements of the characterisation, modelling anddesign methodologies for a wide range of media and many different systems.The chosen research direction for the present thesis slightly deviates fromthis usual path of modelling absorbing materials as bulk media. Here theaim is to investigate the interfaces between the different components of typ-ical absorbers. Indeed, these interface regions are known to be difficult tocharacterise and controlling their properties is challenging for a number ofreasons. Interfaces in sound packages for instance are inherently by-productsof the assembly process and, even if they surely have an important impact onthe acoustic performance, they remain mostly overlooked in the establishedmodelling practices. Therefore, the overall objective of the current doctoralproject is to identify strategies and methods to simulate the effect(s) of un-certainties on the interface physical or geometrical parameters.The present licentiate thesis compiles three works which together form adiscussion about techniques and tools designed in an attempt to efficientlymodel thin layers and small details in rather large systems. As part of thework a section of physical model simplifications is discussed which will laythe ground for the next stages of the research. Two publications on the firsttopic are included, presenting Finite-Element-based hybrid methods that al-low for coating elements in meta-poroelastic systems to be taken into accountand reduce the computational cost of modelling small geometric features em-bedded in large domains. The third included contribution is an anticipation,to a certain extent, of the remainder of the doctoral project, discussing theuse of physical heuristics to simplify porous thin film models. Here a steptowards the modelling of interface zones is taken, departing from numericalsimulations and reflecting instead on the physical description and modellingof thin poroelastic layers.

  • Public defence: 2018-06-13 10:00 Nash/Wardrop, Stockholm
    Johansson, Ingrid
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport Planning, Economics and Engineering.
    Simulation Studies of Impact of Heavy-Duty Vehicle Platoons on Road Traffic and Fuel Consumption2018Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    The demand for road freight transport continues to grow with the growing economy, resulting in increased fossil fuel consumption and emissions. At the same time, the fossil fuel use needs to decrease substantially to counteract the ongoing global warming. One way to reduce fuel consumption is to utilize emerging intelligent transport system (ITS) technologies and introduce heavy-duty vehicle (HDV) platooning, i.e. HDVs driving with small inter-vehicle gaps enabled by the use of sensors and controllers. It is of importance for transport authorities and industries to investigate the effects of introducing HDV platooning. Previous studies have investigated the potential benefits, but the effects in real traffic, both for the platoons and for the surrounding vehicles, have barely been explored. To further utilize ITS and optimize the platoons, information about the traffic situation ahead can be used to optimize the vehicle trajectories for the platoons. Paper I presents a dynamic programming-based optimal speed control including information of the traffic situation ahead. The optimal control is applied to HDV platoons in a deceleration case and the potential fuel consumption reduction is evaluated by a microscopic traffic simulation study with HDV platoons driving in real traffic conditions. The effects for the surrounding traffic are also analysed. Paper II and Paper III present a simulation platform to assess the effects of HDV platooning in real traffic conditions. Through simulation studies, the potential fuel consumption reduction by adopting HDV platooning on a real highway stretch is evaluated, and the effects for the other vehicles in the network are investigated.

  • Nordling, Sofia
    et al.
    Brännström, Johan
    Carlsson, Fredrik
    Lu, Bo
    Salvaris, Evelyn
    Wanders, Alkwin
    Umeå University, Faculty of Medicine, Department of Medical Biosciences.
    Buijs, Jos
    Estrada, Sergio
    Tolmachev, Vladimir
    Cowan, Peter J.
    Lorant, Tomas
    Magnusson, Peetra U.
    Enhanced protection of the renal vascular endothelium improves early outcome in kidney transplantation: peclinical investigations in pig and mouse2018In: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 8, article id 5220Article in journal (Refereed)
    Abstract [en]

    Ischemia reperfusion injury is one of the major complications responsible for delayed graft function in kidney transplantation. Applications to reduce reperfusion injury are essential due to the widespread use of kidneys from deceased organ donors where the risk for delayed graft function is especially prominent. We have recently shown that coating of inflamed or damaged endothelial cells with a unique heparin conjugate reduces thrombosis and leukocyte recruitment. In this study we evaluated the binding capacity of the heparin conjugate to cultured human endothelial cells, to kidneys from brain-dead porcine donors, and to murine kidneys during static cold storage. The heparin conjugate was able to stably bind cultured endothelial cells with high avidity, and to the renal vasculature of explanted kidneys from pigs and mice. Treatment of murine kidneys prior to transplantation reduced platelet deposition and leukocyte infiltration 24 hours post-transplantation, and significantly improved graft function. The present study thus shows the benefits of enhanced protection of the renal vasculature during cold storage, whereby increasing the antithrombotic and anti-adhesive properties of the vascular endothelium yields improved renal function early after transplantation.

  • Bågander, Linnea
    University of Borås, Faculty of Textiles, Engineering and Business.
    BODY OF MOVEMENT - (IN)forming movement2017Conference paper (Refereed)
    Abstract [en]

    This work aims to suggest materialized expressions based the moving body. As a principle of design, it treats the body as a whole and focuses on the in-betweens that the body creates in movement as aesthetics, not looking at its surface or the traditional ways of dividing the body (e.g. sweater, pants).

    In conclusion, the results suggest that the body movement has a spatial continuation as dynamic space that can be materialized. It is a suggestion a principle of design that can be applied in fashion design, choreography, architecture, furniture design. 

  • Chen, Chen
    et al.
    Middleware System Research Group, University of Toronto.
    Tock, Yoav
    IBM Research - Haifa.
    Girdzijauskas, Sarunas
    KTH, School of Electrical Engineering and Computer Science (EECS).
    BeaConvey: Co-Design of Overlay and Routing for Topic-basedPublish/Subscribe on Small-World Networks2018Conference paper (Refereed)
  • Skoog, Therese
    et al.
    Kimber, Birgitta
    Umeå University, Faculty of Medicine, Department of Clinical Sciences.
    Special issue: Social and Emotional Learning and Diversity2017In: The International Journal of Emotional Education, ISSN 2073-7629, E-ISSN 2073-7629, Vol. 9, no 2, p. 1-3Article in journal (Other academic)
  • Public defence: 2018-06-08 12:40 Room 19, Torino, Italia
    Samavati, Mahrokh
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Design and analysis of solid oxide electrolysis-based systems for synthetic liquid fuels production2018Doctoral thesis, monograph (Other academic)
    Abstract [en]

    During the past decades, considerable attention has been dedicated to renewable energy systems. This is due to the increased awareness regarding greenhouse gas emissions as well as limits of the future availability and reliability of conventional energy and power systems. Renewable energy can be considered as free, nearly infinite, and clean; however, such resources have their own drawbacks. Renewables face challenges in meeting instantaneous electricity demand and for utilization as transportation fuels. One of the main challenges of renewable energy sources like solar and wind is due to their variability, making them incapable of meeting the required energy demands at all the time. Therefore it is beneficial to add energy storage for handling supply and demand.

    The current study is dedicated to the design and analysis of an integrated system for production of synthetic fuels as a way of renewable energy storage. The proposed system integrates solid oxide electrolysis, entrained gasification, and Fischer-Tropsch process. The main product of system is Fischer-Tropsch diesel which is produced from steam, CO2, and different renewables, namely: lignocellulosic biomass, solar PV electricity, and wind electricity. This approach has the benefit of storing the excess electrical energy from renewables in the form of chemical energy of the hydrocarbon fuels for further usage during peak hours. Also, using these synthetic fuels results in an increase of the renewable energy share in the transportation system while utilizing existing distribution and conversion technologies.

    The proposed system is analyzed from thermodynamic, economic, and environment perspectives. This study addresses several different research questions, from finding the optimum operating condition of precursor syngas producing subsystems to evaluating the theoretical potential of integrated systems in different locations.

  • Public defence: 2018-06-13 13:00 A3: 1077, Stockholm
    Banerjee, Saikat
    KTH, School of Engineering Sciences (SCI), Physics, Condensed Matter Theory.
    Interacting Dirac Matter2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The discovery of graphene in 2004 has led to a surge of activities focused on the theoretical and experimental studies of materials hosting linearly dispersive quasiparticles during the last decade. Rapid expansion in the list of materials having similar properties to graphene has led to the emergence of a new class of materials known as the Dirac materials. The low energy quasiparticles in this class of materials are described by a Dirac-like equation in contrast to the Schrödinger equation which governs the low energy dynamics in any conventional materials such as metals. The Dirac fermions, as we call these low-energy quasiparticles, in a wide range of materials ranging from the d-wave superconductors, graphene to the surface states of topological insulators share the common property. The particles move around as if they have lost their mass. This feature results in a completely new set of physical effects consisting of various transport and thermodynamic quantities, that are absent in conventional metals.

    This thesis is devoted to studying the properties of bosonic analogs of the commonly known Dirac materials where the quasiparticle are fermionic. In chapter one, we discuss the microscopic origin of the Dirac equation in several fermionic and bosonic systems. We observe identical features of the Dirac materials with quasiparticles of either statistics when the interparticle interaction is absent. Dirac materials with both types of quasiparticles possess the nodal excitations that are described by an effective Dirac-like equation. The possible physical effects due to the linear dispersions in fermionic and bosonic Dirac materials are also outlined.

    In chapter two, we propose a system of superconducting grains arranged in honeycomb lattice as a realization for Bosonic Dirac Materials (BDM). The underlying microscopic dynamics, which give rise to the emergence of Dirac structure in the spectrum of the collective phase oscillations, is discussed in detail. Similarities and differences of BDM systems to the conventional Dirac materials with fermionic quasiparticles are also mentioned. Chapter three is dedicated to the detailed analysis of the interaction effects on the stability and renormalization of the conical Dirac band structure. We find that the type of interaction dictates the possible fate of renormalized Dirac cone in both fermionic and bosonic Dirac materials. We study interaction effects in four different individual systems : (a) Dirac fermions in graphene interacting via Coulomb interactions, (b) Dirac fermions subjected to an onsite Hubbard repulsion, (c) Coulomb repulsion in charged Cooper pairs in honeycomb lattice and (d) Dirac magnons interacting via Heisenberg exchange interaction. The possibility of interaction induced gap opening at the Dirac nodal point described is also discussed in these cases.

    Chapter four mainly concerns the study of a related topic of the synthetic gauge fields. We discuss the possibility of Landau quantization in neutral particles. Possible experimental evidence in toroidal cold atomic traps is also mentioned. A connection to Landau levels in case of magnons is also described. We finally conclude our thesis in chapter five and discuss the possible future directions that can be taken as an extension for our works in interacting Dirac materials.

  • Gnanapragasam, V. J.
    et al.
    Bratt, O.
    Muir, K.
    Lees, L. S.
    Huang, H. H.
    Stattin, Pär
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Urology and Andrology. Department of Surgical Sciences, Uppsala University, Uppsala, Sweden.
    Lophatananon, A.
    The Cambridge Prognostic Groups for improved prediction of disease mortality at diagnosis in primary non-metastatic prostate cancer: a validation study2018In: BMC Medicine, ISSN 1741-7015, E-ISSN 1741-7015, Vol. 16, article id 31Article in journal (Refereed)
    Abstract [en]

    Background: The purpose of this study is to validate a new five-tiered prognostic classification system to better discriminate cancer-specific mortality in men diagnosed with primary non-metastatic prostate cancer.

    Methods: We applied a recently described five-strata model, the Cambridge Prognostic Groups (CPGs 1-5), in two international cohorts and tested prognostic performance against the current standard three-strata classification of low-, intermediate- or high-risk disease. Diagnostic clinico-pathological data for men obtained from the Prostate Cancer data Base Sweden (PCBaSe) and the Singapore Health Study were used. The main outcome measure was prostate cancer mortality (PCM) stratified by age group and treatment modality.

    Results: The PCBaSe cohort included 72,337 men, of whom 7162 died of prostate cancer. The CPG model successfully classified men with different risks of PCM with competing risk regression confirming significant intergroup distinction (p < 0.0001). The CPGs were significantly better at stratified prediction of PCM compared to the current three-tiered system (concordance index (C-index) 0.81 vs. 0.77, p < 0.0001). This superiority was maintained for every age group division (p < 0.0001). Also in the ethnically different Singapore cohort of 2550 men with 142 prostate cancer deaths, the CPG model outperformed the three strata categories (C-index 0.79 vs. 0.76, p < 0.0001). The model also retained superior prognostic discrimination in the treatment sub-groups: radical prostatectomy (n =3D 20,586), C-index 0.77 vs. 074; radiotherapy (n =3D 11,872), C-index 0.73 vs. 0.69; and conservative management (n =3D 14,950), C-index 0.74 vs. 0.73. The CPG groups that sub-divided the old intermediate-risk (CPG2 vs. CPG3) and high-risk categories (CPG4 vs. CPG5) significantly discriminated PCM outcomes after radical therapy or conservative management (p < 0.0001).

    Conclusions: This validation study of nearly 75,000 men confirms that the CPG five-tiered prognostic model has superior discrimination compared to the three-tiered model in predicting prostate cancer death across different age and treatment groups. Crucially, it identifies distinct sub-groups of men within the old intermediate-risk and high-risk criteria who have very different prognostic outcomes. We therefore propose adoption of the CPG model as a simple-to-use but more accurate prognostic stratification tool to help guide management for men with newly diagnosed prostate cancer.

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