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  • Windmark, Marcus
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology.
    Evaluating Anomaly Detection Algorithms in Power Consumption Data2017Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The quality of data is an important aspect when performing data scientific tasks.Having a clean ground truth dataset is critical to be able to derive analytical resultsfrom experiments.

    In this thesis, an automated method of checking the correctness of new data against adefined ground truth dataset is evaluated. With the use of machine learningalgorithms, anomaly detection was applied to separate normal and abnormalmeasurements of power consumption data, collected as time series from real worldhousehold appliances. Due to high variance in the energy data, the problem ofdetecting anomalies was solved with generative models, using the reconstructionerror as anomaly score. Extensive experiments were performed using a range ofparameters with three different models, simple regression with Multilayer Perceptron(MLP), Long Short-Term Memory (LSTM) and Dilated Causal Convolutional NeuralNetwork (DC-CNN).

    The results of the experiments show promising performance of using generativemodels for anomaly detection. All three models managed to learn the general powersignature of the household appliance measurements, with a varying degree of successrelative to the complexity of the signature. Out of the three models, the experimentsidentified the DC-CNN to be the best performing. Compared with the other models,the DC-CNN had both a higher success rate at classifying anomalous sequences aswell as a faster computational speed.

    Finally, this thesis concludes that fine-tuning the parameters of the models to thespecific task is required to achieve good performance. Finding a good combination ofmodel and parameter values is especially important in the case of handlingmeasurements from household appliances, due to the complexity of the data.

  • Fornander, Victor
    et al.
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Social Sciences, Department of Business Studies.
    Lindquist, Oscar
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Social Sciences, Department of Business Studies.
    Morgonstjärnornas krig: Morningstar-betyg & fonders framtida avkastning2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Studien undersöker om Morningstars betygssystem för fonder, kan ses som en indikation på fondens riskjusterade avkastning tolv månader framåt i tiden. Hypotesen är att det finns ett positivt samband mellan Morningstar-betyg och framtida riskjusterad avkastning, mätt i Jensen’s Alpha och Sharpekvot. Med ett urval om 107 svenska aktiefonder, över en tidsperiod mellan 2007 och 2016, genomförs en regressionsanalys som sedan kopplas till teorin om marknadens effektivitet samt tidigare forskning om varaktighet i avkastning. Resultatet visar att det finns indikationer på att fonder med det högsta Morningstar-betyget (fem stjärnor) kommer prestera bättre än fonder med de lägre betygen (tre till en stjärnor). Dock finns litet stöd för att fem-stjärniga fonder skulle prestera bättre än fyra-stjärniga fonder. Förklaringsgraden är dessutom nära noll vilket gör det svårt att dra generella slutsatser över hela tidsperioden. Möjligen kan Morningstar-betyg användas som ett verktyg för att identifiera vilka fonder som bör undvikas, vilket kan underlätta för investerare.

  • Clegg, Mathew
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology.
    Scheduling Network PerformanceMonitoring in The Cloud2017Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    New trends in the market, adapted to service oriented consumption models, haveunfolded new opportunities in how we monitor network performance. This thesis,introduces a new containerized, decentralized and concurrent scheduler for activenetwork performance monitoring called Controlled Priority Scheduling (CPS). Thescheduler is implemented to suit the container monitoring platform, ConMon. Thescheduler is implemented to run inside distributed containers, where the purpose isto deploy the scheduling container on the same host as the running application.Performing the monitoring in such way gives a better understanding of the networkperformance an application can utilize, compared to the capacity the network canoffer. The CPS scheduler showed an improved monitoring time granularity whencompared too other distributed and decentralized schedulers. In addition, CPSmanages to perform a consistent, near-cyclic monitoring pattern, over a dynamicallyadaptable monitoring cluster, without causing any monitoring conflicts.

  • Färjsjö, Felix
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology.
    Stenberg, Eric
    Ensuring Continuous Security in the Cloud and Compliance with GDPR2017Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Scania is currently in the process of migrating from an on-premise infrastructure to a cloud environment. In parallel, General Data Protection Regulation (GDPR) will come into effect in 2018 and the combination of migrating infrastructure and a new regulation resulted in a need for guidance in how to progress. This thesis' goal is to establish guidelines for the Connected Services department on how to conduct development in a cloud environment whilst complying with GDPR. The finalized versions of these guidelines are the result of several interviews with experts in the field along with a proof of concept on how to secure an example application in a cloud environment.

  • Wijnbladh, Max
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology.
    Experimental Study: Link-QualityEstimations in a City-DeployedWireless Sensor Network2017Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    As the capabilities and scalability of the Internet grow largerand become more advanced, new opportunities arise that enableusers to make use of this enhanced manner in which to distributedata. One particular example of this is Wireless Sensor Networks -networks consisting of small sensors with wireless communicationcapabilities, which can monitor and record environmental phenomenawith the intention of forwarding the obtained information toindividual clients or centralized servers for data mining. Thesetypes of networks are often deployed in relatively hazardousenvironments, which may challenge the efficiency and performanceof the wireless connectivity between nodes.

    A joint effort between multiple partners, called the GreenIoTproject, aims to deploy a Wireless Sensor Network in Uppsala,Sweden. The partners of the project seek to learn more about thelevel of performance that can be expected by the network invarious scenarios, such as when the distance between thetransmitting nodes is increased and when the line of sight betweenthem is disrupted. The insights gained from this research are tobe used for optimal configuration and deployment of the nodes, inorder to ensure a reliable and high-performance network. Using theknowledge obtained from previous work in the area, methods andexperiments were developed for assessing the effects that thesedemanding situations have on the performance of the wirelesslinks.

    The results showed that the observed metrics of the links, such asthe strength of the received signal and the packet receptionratio, differed greatly depending on the environment in which theexperiments were conducted. Based on the outcomes of theexperiments, a conclusion was made that field tests on planneddeployment sites before installation in the testbed will likely benecessary to ensure sufficient reliability in the network. Wheninvestigating potential areas of improvements to the existingtestbed architecture, it was found in related work that techniquessuch as adaptive power and channel control provide higherperformance in lossy and high-density networks. Since the nodesused in the project are compatible with existing solutionsproviding this functionality, these kinds of enhancements shouldprove to be beneficial for the future operation of the GreenIoTtestbed.

  • Jiang, Mengying
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Social Sciences, Department of Business Studies.
    Does the time Machine exist?: Nostalgic consumption of Chinese one-child generation2017Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Nostalgia in consumer behavior is shown to be effective. Every generation has their own views of nostalgia. Their ability, proneness and intensity to process nostalgia is different for each generation. The Chinese one-child generation in terms of their special growth environment and characteristics was chosen as the object of study. The thesis begins with the model of nostalgic consumption. The model includes the indirect factors towards nostalgia proneness, the direct factors towards nostalgia intensity and the consumption of nostalgic products. Two qualitative methods were used to collect data, which are the focus group and the individual interview. Two nostalgic brands, one Finnish brand Nokia and a Chinese brand Arctic Ocean Soda (AOS) were used to encourage the discussion of the focus group. There are some surprised results came from the focus group and the following individual interview. These results helped to refine the model. Finally, some suggestions were given to Nokia and AOS companies about how to attract Chinese one-child generation.

  • Nerbel, Jan Frederic
    et al.
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Social Sciences, Department of Business Studies.
    Hammarsten, Ellinor
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Social Sciences, Department of Business Studies.
    Hedlund, Tobias
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Social Sciences, Department of Business Studies.
    Advancing Towards Model-Based Decision-Making: A Qualitative Case Study at a Swedish Whisky Start-Up2017Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This study investigates decision-making processes in respect to the maturation time and the marketed quantities of single malt whisky in a Swedish distillery start-up. At first, the literature regarding decision-making in both start-ups and larger organisations has been reviewed. It can be concluded that decision-making in start-ups, compared to their established counterparts, is more based on heuristics and continuously exposed to several biases. In the following, a general resource exploitation model is presented in the context of deterministic decision-making and adjusted towards whisky casks as deposits of nonrenewable resources. The consecutive case study is conducted in a Swedish distillery start-up. Findings indicate that the start-up is exposed to a high market dynamic and expert-knowledge is of high importance. In the start-up, these experts make decisions regarding the maturation times and the quantities of the marketed whisky. Nevertheless, the optimal exploitation model can be implemented into daily operations and delivers additional data for decisions. Planning can evolve from a mainly cost-based towards a profit-maximising perspective. However, the quality of the model results are expected to be limited, due to the deterministic nature of the model in a highly dynamic environment. This effect may be even amplified by input parameters, which cannot be precisely determined.Therefore, the industry knowledge of the decision-maker appears to be the most important factor for decision-making processes in this industry.

  • Morell Bonin, Tyra
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Prestationsanalys av granulerataktivt kol (GAC) – en jämförelse mellan två etablerade GAC-typer2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    There are multiple steps to be done in the drinking water treatment process. The product must obtain high quality and to do so, it must reach certain requirements. One of the treatment steps in Görväln water treatment plant, Stockholm, is to use granular active carbon (GAC). The GAC function is to filter away taste and odor in addition to acting as a chemical barrier, although the latter does not work properly in the water treatment plant today.The project´s aim is comparing the performance of two types of GAC, Norit® 830 W and FiltraSorb® 400, together with the effect of longer (21 minutes) and shorter (7 minutes) contact time (EBCT). The contact time (EBCT) is the time, in minutes, that a body of water is in contact with the GAC-filter. A longer EBCT, means lower flow, which leads to longer time for the GAC to adsorb contaminants from the water.To evaluate the difference between the GAC-types a column-test was constructed. The test allows a direct comparison to full scale operations. The water used during this study was taken directly after the sand filtration process in Görväln. The water is clear and particles visible to the naked eye are eliminated during the sand filtration. However, the small dissolved organic components (carbon) are hard to remove, which makes the GAC-filter important.The performance of the GAC was evaluated by the removal efficiency of TOC, DOC and evaluation of fluorescence and absorbance capacity. The result indicated a better performance for both GAC using a longer contact time. Best effect of the long contact time was seen during the fluorescence measurement, where calculated indexes and removal of specific compounds were distinguished.The difference between longer, 21 minutes, and shorter, 7 minutes, contact time was not as significant as the difference between the two types of GAC. FiltraSorb® 400 had a significant higher adsorbance capacity for DOC and TOC, 30 % better than Norit® 830 W, at the same bed volume. Norit® 830 W reached breakthrough much faster (~80 %) than FiltraSorb® 400 (~50%) at around 4700 bed volumes.

  • Nordlund, Michael
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - BMC, Organic Chemistry.
    Carbon Nanostructures – from Molecules to Functionalised Materials: Fullerene-Ferrocene Oligomers, Graphene Modification and Deposition2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The work described in this thesis concerns development, synthesis and characterisation of new molecular compounds and materials based on the carbon allotropes fullerene (C60) and graphene.

    A stepwise strategy to a symmetric ferrocene-linked dumbbell of fulleropyrrolidines was developed. The versatility of this approach was demonstrated in the synthesis of a non-symmetric fulleropyrrolidine-ferrocene-tryptophan triad. A new tethered bis-aldehyde, capable of regiospecific bis-pyrrolidination of a C60-fullerene in predominantly trans fashion, was designed, synthesised and reacted with glycine and C60 to yield the desired N-unfunctionalised bis(pyrrolidine)fullerene. A catenane dimer composed of two bis(pyrrolidine)fullerenes was obtained as a minor co-product. From the synthesis of the N-methyl analogue, the catenane dimer could be separated from the monomeric main product and fully characterised by NMR spectroscopy. Working towards organometallic fullerene-based molecular wires, the N-unfunctionalised bis(pyrrolidine)fullerene was coupled to an activated carboxyferrocene-fullerene fragment by amide links to yield a ferrocene-linked fullerene trimer, as indicated by mass spectrometry from reactions carried out at small scale

    A small library of conjugated diarylacetylene linkers, to be coupled to C60 via metal-mediated hydroarylation, was developed. Selected linker precursors were prepared and characterised, and the hydroarylation has been adapted using simple arylboronic acids.

    Few-layer graphene was prepared and dip-deposited from suspension onto a piezoelectric polymer substrate. Spontaneous side-selective deposition was observed and, from the perspective of non-covalent interaction, rationalised as being driven by the inbuilt polarization of the polymer.

    Aiming for selectively edge-oxidized graphene, a number of graphitic materials were treated with a combination of ozone and hydrogen peroxide under sonication. This mild, metal-free procedure led to edge-oxidation and exfoliation with very simple isolation of clean materials indicated by microscopy, spectroscopy, and thermogravimetric analysis.

    List of papers
    1. Mono- and diamides of 1,1’-dicarboxyferrocene: a stepwise approach to ferrocene-linked triads
    Open this publication in new window or tab >>Mono- and diamides of 1,1’-dicarboxyferrocene: a stepwise approach to ferrocene-linked triads
    (English)Manuscript (preprint) (Other academic)
    Abstract [en]

    An improved route to the monomethyl ester of 1,1´-dicarboxyferrocene is described. The compound is a key intermediate for the assembly of ferrocene-bridged triads by stepwise amidation. This renders possible symmetric as well as non-symmetric diamides, exemplified by the preparaton of a symmetric ferrocene-linked fulleropyrrolidine dumbbell and a non-symmetric fulleropyrrolidine-ferrocene-tryptophan triad.

    Keyword
    Fullerene, Ferrocene, Dumbbell, Triad
    National Category
    Organic Chemistry Inorganic Chemistry
    Identifiers
    urn:nbn:se:uu:diva-327167 (URN)
    Available from: 2017-08-06 Created: 2017-08-06 Last updated: 2017-08-06
    2. Catenane dimer formation in tether-assisted trans-bis-pyrrolidination of [60]fullerene
    Open this publication in new window or tab >>Catenane dimer formation in tether-assisted trans-bis-pyrrolidination of [60]fullerene
    (English)Manuscript (preprint) (Other academic)
    Abstract [en]

    Trans-bis-pyrrolidination of [60]fullerene employing a new bis-aldehyde tether with appended octadecyloxy substituents proceeded to give the desired product as well as catenane dimers. For pyrrolidinations employing sarcosine, the products were separable, and characterisation by NMR spectroscopy, including diffusion-ordered spectroscopy (DOSY), provided unambiguous proof that the high-mass product was a symmetric non-covalent catenane. No catenane or other high-mass products were observed for reactions employing a tether without the octadecyloxy substituents.

    Keyword
    Fullerene, Tether, Catenane, NMR
    National Category
    Organic Chemistry Inorganic Chemistry
    Identifiers
    urn:nbn:se:uu:diva-327166 (URN)
    Available from: 2017-08-06 Created: 2017-08-06 Last updated: 2017-08-09
    3. Towards [60]fullerene-based molecular wires: amide-interlinked ferrocene-[60]fullerene oligomers
    Open this publication in new window or tab >>Towards [60]fullerene-based molecular wires: amide-interlinked ferrocene-[60]fullerene oligomers
    (English)Manuscript (preprint) (Other academic)
    Abstract [en]

    Design and synthesis of amide-linked ferrocene-fulleropyrrolidine oligomers is presented, with initial characterisation that confirms products containing three or four ferrocene-bridged fullerene units. Side-products have been identified; the encountered issues concerning their formation and general solubility motivated modifications of the synthesis strategy.

    Keyword
    Fullerene, Ferrocene, Trimer, Oligomers
    National Category
    Organic Chemistry Inorganic Chemistry
    Identifiers
    urn:nbn:se:uu:diva-327168 (URN)
    Available from: 2017-08-06 Created: 2017-08-06 Last updated: 2017-08-06
    4. Diarylacetyene-linked [60]fullerene dumbbells via metal-catalyzed couplings
    Open this publication in new window or tab >>Diarylacetyene-linked [60]fullerene dumbbells via metal-catalyzed couplings
    (English)Manuscript (preprint) (Other academic)
    Abstract [en]

    This preliminary manuscript describes the synthesis and characterization of new di(4-bromoaryl)acetylenes by Sonogashira cross-coupling, initial attempts to transform model aryl bromides to aryl boronic acids as well as a model study of Rh-catalysed hydroarylation of [60]fullerene with aryl boronic acids, aiming towards “all carbon”-linked [60]fullerene dumbbells.

    Keyword
    Fullerene, Metal-catalyzed addition, Sonogashira, Hydroarylation
    National Category
    Organic Chemistry
    Identifiers
    urn:nbn:se:uu:diva-327164 (URN)
    Available from: 2017-08-04 Created: 2017-08-04 Last updated: 2017-08-06
    5. Side-selective self-assembly of graphene and FLG on piezoelectric PVDF from suspension
    Open this publication in new window or tab >>Side-selective self-assembly of graphene and FLG on piezoelectric PVDF from suspension
    Show others...
    2016 (English)In: Journal of Physics D: Applied Physics, ISSN 0022-3727, E-ISSN 1361-6463, Vol. 49, no 7, 07LT01Article in journal (Refereed) Published
    Abstract [en]

    The deposition of few-layer graphene by self-assembly from suspension onto a piezoelectric polymer substrate is presented. The graphene self-assembles with negligible overlap between flakes, and with high selectivity for one of the faces of the substrate, an observation which is discussed and rationalized. A computational study on a model system further confirms the theory and supports the experimental results. The highest obtained degree of surface coverage was estimated to 77%.

    Keyword
    graphene, PVDF, self-assembly, selective, deposition
    National Category
    Organic Chemistry Other Physics Topics Inorganic Chemistry
    Identifiers
    urn:nbn:se:uu:diva-276051 (URN)10.1088/0022-3727/49/7/07LT01 (DOI)000369403700001 ()
    Funder
    Swedish Research CouncilKnut and Alice Wallenberg FoundationThe Kempe Foundations
    Available from: 2016-02-09 Created: 2016-02-09 Last updated: 2017-08-06Bibliographically approved
    6. Edge oxidation of graphite using a combined hydrogen peroxide - ozone treatment under sonication conditions
    Open this publication in new window or tab >>Edge oxidation of graphite using a combined hydrogen peroxide - ozone treatment under sonication conditions
    (English)Manuscript (preprint) (Other academic)
    Abstract [en]

    A mild method for edge oxidation of graphite using ultrasonication in the presence of ozone and hydrogen peroxide is described. The method benefits from sustainable reagents - no metals or oxidising mineral acids are involved; and easy purification of the resulting material. Initial characterisation of the material and its dispersibility by spectroscopic methods and thermogravimetric analysis is presented.

    Keyword
    Edge oxidation, Graphite, Graphene, Hydrogen peroxide, Ozone
    National Category
    Materials Chemistry Organic Chemistry
    Identifiers
    urn:nbn:se:uu:diva-327165 (URN)
    Available from: 2017-08-06 Created: 2017-08-06 Last updated: 2017-08-09