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  • 101.
    Aikio Englund, Rebecca
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    A study of calculation models for fatigue life prediction: A thesis accomplished together with GKN Aerospace2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    GKN Aerospace in Trollhättan don’t use the latest ANSYS version and need to upgrade their life analysis models. The aim with this thesis is to do a study of the new models and investigate the times required for the calculations. A flight mission were chosen and this mission together with different life analysis models were run in the GKN in house program Life Analysis System. The results were analyzed and depending on the results additional runs were made or the problem were sent to the life management group at GKN Aerospace. Strain levels versus time were also plotted for the runs with the new models to get a perception where any problems occurs. The results from the model 4.10.149 had no variations between equal runs for the high pressure turbine and the low pressure turbine but there was a variation between the results when equal runs was made with the high pressure compressor. The results from model 4.10.157 and 4.10.124 and 4.10.160 and 4.10.173 had variations in the fatigue life for equal runs. The variations can depend on that the calculations converges to different solutions, the reason for this can depend on the non-linear contact elements. The variation in the results between equal runs occurs when the model uses two or more cores. The time required for the calculation becomes faster with the use of more cores. The longest duration had model 4.10.173 because of the many requirements for the calculations in this model. The problem with the variation in the results is sent to ANSYS.

  • 102.
    Aikio, Felix
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Andersson, Alvin
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Sjuksköterskestudenters upplevelser av att vårda patienter i livets slutskede: En empirisk studie2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
  • 103.
    Aimal, Pir
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics.
    Mohsin, Main
    Analyzing Voltage control and reactive power support from full power converter wind turbine2011Independent thesis Advanced level (degree of Master (Two Years)), 80 credits / 120 HE creditsStudent thesis
  • 104.
    Airola, Rasmus
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science.
    Hager, Kristoffer
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science.
    Image Classification, Deep Learning and Convolutional Neural Networks: A Comparative Study of Machine Learning Frameworks2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The use of machine learning and specifically neural networks is a growing trend in software development, and has grown immensely in the last couple of years in the light of an increasing need to handle big data and large information flows. Machine learning has a broad area of application, such as human-computer interaction, predicting stock prices, real-time translation, and self driving vehicles. Large companies such as Microsoft and Google have already implemented machine learning in some of their commercial products such as their search engines, and their intelligent personal assistants Cortana and Google Assistant.

    The main goal of this project was to evaluate the two deep learning frameworks Google TensorFlow and Microsoft CNTK, primarily based on their performance in the training time of neural networks. We chose to use the third-party API Keras instead of TensorFlow's own API when working with TensorFlow. CNTK was found to perform better in regards of training time compared to TensorFlow with Keras as frontend. Even though CNTK performed better on the benchmarking tests, we found Keras with TensorFlow as backend to be much easier and more intuitive to work with. In addition, CNTKs underlying implementation of the machine learning algorithms and functions differ from that of the literature and of other frameworks. Therefore, if we had to choose a framework to continue working in, we would choose Keras with TensorFlow as backend, even though the performance is less compared to CNTK.

  • 105.
    Aitman, Therese
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Health Sciences.
    Sjuksköterskans roll i omvårdnaden av patienter med terminal oro: en litteraturstudie2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Introduktion: Terminal oro är i denna litteraturstudie en beteckning för en samling av symtom som utgör en särskild form av lidande i livets slutskede, sprunget ur fysisk, emotionell och existentiell utsatthet. Reversibla orsaker endast kan påvisas i uppskattningsvis hälften av fallen, vilket gör terminal oro till ett renodlat omvårdnadsproblem där sjuksköterskans roll är central.

    Syfte: Att belysa sjuksköterskans roll i omvårdnaden av patienter med terminal oro.

    Metod: Polit och Becks (2017) niostegsmodell. Litteratursökningar i Cinahl och PubMed resulterade i elva artiklar som kvalitetsgranskades och analyserades enligt Colaizzis (1978 refererad i Polit & Beck 2017) fenomenologiska metod.

    Resultat: Under databearbetningen framkom fem underkategorier (Att stå utanför, Att känna sig otillräcklig, Att söka samförstånd, Att vårda i relationen, Att skydda patienten), två huvudkategorier (Avstånd, Närhet) samt en övergripande kategori (Strävan efter att trösta).

    Slutsats: Resultatet visar utmaningar i omvårdnaden samt strategier för att hantera dessa. Medvetenhet och kompetens om terminal oro, tydliga rutiner för uppföljning av dess symtom samt reflektion tillsammans med arbetskamrater gav sjuksköterskorna större möjligheter att utföra omvårdnaden på ett tillfredsställande sätt. Närvaro i den dagliga omvårdnaden och ett respektfullt bemötande etablerade en tillitsfull relation med patienterna. När sjuksköterskorna hade god kännedom om patienterna kunde multidimensionella behov mötas och välbefinnande uppnås.

  • 106.
    Akervall, Elin
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Health Sciences (from 2013).
    Engström, Alexandra
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Health Sciences (from 2013).
    Copingstrategier hos patienter med kolorektalcancer: en litteraturstudie2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
  • 107.
    Akil, Mahdi
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Mancini, L. V.
    Universita di Roma Sapienza, Rome, Italy.
    Venturi, D.
    Universita di Roma Sapienza, Rome, Italy.
    Multi-covert channel attack in the cloud2019In: 2019 6th International Conference on Software Defined Systems, SDS 2019, Institute of Electrical and Electronics Engineers Inc. , 2019, p. 160-165Conference paper (Refereed)
    Abstract [en]

    Frequently, it is believed that the adoption of encryption is adequate to ensure the safety of the message. However, encryption only restricts unapproved individuals from decoding the message. Whereas in many circumstances, the mere presence of communication or variations in communication patterns, such as an increase in message rate, is sufficient to raise doubt and initiate alerts. One of the best ways to bypass that is by using covert channels. In this paper, we create innovative protocols that use multiple covert channels working in parallel to exfiltrate data from a remote-controlled machine to our server. The provided protocols guarantee the completeness and unforgeability of the exfiltrated data. We analyze the difference in performance between the created protocols and provide mathematical equations to evaluate them.

  • 108.
    Akrin, Catrine
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Health Sciences (from 2013).
    Varför ökar förskrivningen av antidepressiva till barn och ungdomar?: En litteraturstudie om farmakologisk behandling för barn och ungdomar med psykisk ohälsa2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
  • 109.
    Aksoy, Can Aksoy
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Fuel consumption measurements and fuelconditioning in high-pressure fuel systemfor single cylinder test cell2019Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This master thesis is part of a bigger project issued by AVL with the purpose to design a high pressure compression ignition fuel system for their single cylinder test cell at their facility in Södertälje. Typically compression-ignition fuel tests are being run within an operating pressure range of 500-2400 bar, but this system has to be able to run with pressures up to 3500 bar. The project was intended to be carried out by two participants where this master thesis covers the evaluation of how fuel consumption rates shall be measured in the system described above as well as how the fuel shall be conditioned.

    The selected concept for measuring fuel consumption rate was based on measuring the mass flow on the low-pressure side of the system with a Coriolis flowmeter. The chosen temperature sensor for monitoring the temperature on the high-pressure side was a K-type thermocouple which would be directly connected to the fuel rail in the system. A bleeder was selected on the basis that it had been used in one of AVL's old test cells. A heat exchanger could not be chosen. However a rough estimation of the capacity needed for a heat exchanger was calculated for future reference.

    The methodology used to develop a concept was based on the engineering project process taught to students at Karlstad University. First a project plan was made followed by a solution-independently expressed product specification including a specification of requirements and QFD-matrix. Several concepts were generated for measuring the fuel consumption by evaluating different measuring principles, available components, possible positions of the components within the system and combinations with different fuel supply concepts. Less extensive methods were used for the remaining tasks in the detailed engineering phase of the project. The concepts were compared using Pugh's analysis and a concept was selected in collaboration with AVL.

    The majority of the objectives for this master thesis could be successfully carried out. The documentation and drawings requested by the client, manufacturing of the system, implementation and validation into the test cell could not be done due to lack of time. This, along with the selection of a heat exchanger and low-pressure thermocouple was left for future work.

  • 110.
    Al- Askery, Akram
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Health Sciences (from 2013).
    Förskrivningen av antineoplastiska monoklonala antikroppar i Sverige: En registerstudie över förskrivningsskillnaden mellan de olika delarna av landet mellan åren 2000–20162018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
  • 111.
    Al Ubeidi, Dina
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Effekter av lignin och cellulosa som additiv vid pelletering av träpellets2018Independent thesis Basic level (professional degree), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    Using renewable energy sources, such as wood fuel pellets, can create conditions for sustainable development. Wood pellet production is increasing globally and the increase is expected to continue in the future. This means that the pellets industry must start to increase their raw material base, for an example by using by-products as bark. In order to improve the pellet properties and the pelleting process, additive can be used. The purpose of this study was to increase the knowledge of how lignin and cellulose as additives affect pelleting properties on pellets produced from spruce-and birch sawdust and aspen bark. The aim was to find out what effects lignin and cellulose have on the density of the pellets, hardness, moisture absorption, and energy for compression and friction.

    Lignin and cellulose were tested as additives in the amount of 0, 1, 2.5 and 4% for pelletizing spruce-and birch sawdust as well as aspen bark in a single pellet press. The pellets were produced at a die temperature of 120, 100oC and 100, and a moisture content of 12, 10 and 14%.

    For pellets produced by spurce sawdust and aspen bark, the addition of lignin resulted in improved pellets, without the compression and friction energy changing. In the case of pellets produced by birch sawdust, the addition of lignin and cellulose did not change the pellet properties, on the other hand, it increased the energy for compression and friction. Both lignin and cellulose reduced the moisture absorption capacity of pellets. 

  • 112.
    Alaqra, Ala Sarah
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    The Wicked Problem of Privacy: Design Challenge for Crypto-based Solutions2018Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Data privacy has been growing in importance in recent years, especially with the continuous increase of online activity. Researchers study, design, and develop solutions aimed at enhancing users’ data privacy. The wicked problem of data privacy is a continuous challenge that defies straightforward solutions. Since there are many factors involved in data privacy, such as technological, legal, and human aspects, we can only aim at mitigating rather than solving this wicked problem. Our aim was to focus on human aspects for designing usable crypto-based privacy-enhancing solutions.  In this thesis, we followed a user centered design method by using empirical qualitative means for investigating user’s perceptions and opinions of our solutions. Most of our work has focused on redactable signatures in the cloud context within the eHealth use-case. Redactable signatures are  a privacy enhancing scheme allowing to remove parts of a signed document by a specified party for achieving data minimization without invalidating the respective signature.

    We mainly used semi-structures interviews and focus groups in our investigations. Our results yielded key HCI considerations as well as guidelines of different means for supporting the design of future solutions.

  • 113.
    Alaqra, Ala Sarah
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Kane, Bridget
    Karlstad University, Faculty of Arts and Social Sciences (starting 2013), Karlstad Business School (from 2013).
    Fischer-Hübner, Simone
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science. Karlstad University, Faculty of Economic Sciences, Communication and IT, Centre for HumanIT. Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Analysis on Encrypted Medical Data In The Cloud, Should We Be Worried?: A Qualitative Study of Stakeholders' PerspectivesManuscript (preprint) (Other academic)
  • 114.
    Alaqra, Ala Sarah
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Wästlund, Erik
    Karlstad University, Faculty of Arts and Social Sciences (starting 2013), Service Research Center (from 2013). Karlstad University, Faculty of Arts and Social Sciences (starting 2013), Department of Social and Psychological Studies (from 2013).
    Reciprocities or Incentives?: Understanding Privacy Intrusion Perspectives and Sharing Behaviors2019In: HCI for Cybersecurity, Privacy and Trust: First International Conference, HCI-CPT 2019, Held as Part of the 21st HCI International Conference, HCII 2019, Orlando, FL, USA, July 26–31, 2019, Proceedings / [ed] Abbas Moallem, Cham, Switzerland: Springer, 2019, p. 355-370Conference paper (Refereed)
    Abstract [en]

    The importance and perception of privacy varies from one context to the other. However, everyone values his or her privacy to a certain extent. The subjectivity of that value, attitudes, and behaviors would depend on different entangling factors. It is important to understand the motivation that influences human behavior, whether to protect or share their information. In this paper, we aim at understanding the boundaries of privacy, factors influencing information sharing behavior including experiences (reciprocities of privacy), and efforts taken to protect one’s data. We collected data using quantitative (survey/quiz) and qualitative means (focus groups). In the survey/quiz, our results showed that intrusion experience and awareness have a significant correlation between sharing of data. Furthermore, our focus groups results yielded details on influencing factors for privacy reciprocities and tradeoffs. We discuss our results in terms of privacy incentives and factors influencing the sharing behavior of their information. Finally, we highlight the complexity of behavior where intrinsic and extrinsic motivations could clash and result in a dilemma such as the privacy paradox phenomenon. © 2019, Springer Nature Switzerland AG.

    The full text will be freely available from 2020-06-12 08:00
  • 115.
    Alaqra, Alaa
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Tinkering the Wicked Problem of Privacy: Design Challenges and Opportunities for Crypto-based Services2020Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Data privacy has been growing in importance in recent years, especially with the constant increase of online activity. Consequently, researchers study, design, and develop solutions aimed at enhancing users' data privacy. The wicked problem of data privacy is a dynamic challenge that defies straightforward solutions. Since there are many factors involved in data privacy, such as technological, legal, and human aspects, we can only aim at mitigating rather than solving this wicked problem.

    Our aim was to explore challenges and opportunities with a focus on human aspects for designing usable crypto-based privacy-enhancing technologies (PETs). Mainly, there were three PETs in the cloud context included in our studies: malleable signatures, secret sharing, and homomorphic encryption. Based on the three PETs, services were developed within European research projects that were the scope of our user studies. We followed a user-centered design approach by using empirical qualitative and quantitative means for collecting study data. Our results and tinkering conveyed (i) analysis of different categories of user's perspectives, mental models, and trade-offs, (ii) user requirements for PET services, and (iii) user interface design guidelines for PET services. In our contributions, we highlight considerations and guidelines for supporting the design of future solutions.

  • 116.
    Alaqra, Alaa
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Fischer-Hübner, Simone
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Framner, Erik
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Enhancing Privacy Controls for Patients via a Selective Authentic Electronic Health Record Exchange Service: Qualitative Study of Perspectives by Medical Professionals and Patients2018In: Journal of Medical Internet Research, ISSN 1438-8871, E-ISSN 1438-8871, Vol. 20, no 12, article id e10954Article in journal (Refereed)
    Abstract [en]

    Background: Patients' privacy is regarded as essential for the patient-doctor relationship. One example of a privacy-enhancing technology for user-controlled data minimization on content level is a redactable signature. It enables users to redact personal information from signed documents while preserving the validity of the signature, and thus the authenticity of the document. In this study, we present end users' evaluations of a Cloud-based selective authentic electronic health record (EHR) exchange service (SAE-service) in an electronic health use case. In the use case scenario, patients were given control to redact specified information fields in their EHR, which were signed by their doctors with a redactable signature and transferred to them into a Cloud platform. They can then selectively disclose the remaining information in the EHR, which still bears the valid digital signature, to third parties of their choice. Objective: This study aimed to explore the perceptions, attitudes, and mental models concerning the SAE-service of 2 user roles: signers (medical professionals) and redactors (patients with different technical knowledge) in Germany and Sweden. Another objective was to elicit usability requirements for this service based on the analysis of our investigation. Methods: We chose empirical qualitative methods to address our research objective. Designs of mock-ups for the service were used as part of our user-centered design approach in our studies with test participants from Germany and Sweden. A total of 13 individual walk-throughs or interviews were conducted with medical staff to investigate the EHR signers' perspectives. Moreover, 5 group walk-throughs in focus groups sessions with (N=32) prospective patients with different technical knowledge to investigate redactor's perspective of EHR data redaction control were used. Results: We found that our study participants had correct mental models with regard to the redaction process. Users with some technical models lacked trust in the validity of the doctor's signature on the redacted documents. Main results to be considered are the requirements concerning the accountability of the patients' redactions and the design of redaction templates for guidance and control. Conclusions: For the SAE-service to be means for enhancing patient control and privacy, the diverse usability and trust factors of different user groups should be considered.

  • 117.
    Alaqra, Ala(a)
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Fischer-Hübner, Simone
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Groß, Thomas
    Newcastle University, UK.
    Lorünser, Thomas
    Austrian Institute of Technology, Austria.
    Slamanig, Daniel
    Graz University of Technology, Austria.
    Signatures for Privacy, Trust and Accountability in the Cloud: Applications and Requirements2015In: Privacy and Identity Management. Time for a Revolution?: 10th IFIP WG 9.2, 9.5, 9.6/11.7, 11.4, 11.6/SIG 9.2.2 International Summer School, Edinburgh, UK, August 16-21, 2015, Revised Selected Papers / [ed] David Aspinall, Jan Camenisch, Marit Hansen, Simone Fischer-Hübner, Charles Raab, Springer Publishing Company, 2015, Vol. 476, p. 79-96Conference paper (Refereed)
    Abstract [en]

    This paper summarises the results of a workshop at the IFIP Summer School 2015 introducing the EU Horizon 2020 project PRISMACLOUD, that is, Privacy and Security Maintaining Services in the Cloud. The contributions of this summary are three-fold. Firstly, it provides an overview to the PRISMACLOUD cryptographic tools and use-case scenarios that were presented as part of this workshop. Secondly, it distills the discussion results of parallel focus groups. Thirdly, it summarises a ``Deep Dive on Crypto'' session that offered technical information on the new tools. Overall, the workshop aimed at outlining application scenarios and eliciting end-user requirements for PRISMACLOUD.

  • 118.
    Alaqra, Alaa
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Fischer-Hübner, Simone
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Pettersson, John
    Karlstad University, Faculty of Arts and Social Sciences (starting 2013), Centre for HumanIT (from 2013).
    Wästlund, Erik
    Karlstad University, Faculty of Arts and Social Sciences (starting 2013), Service Research Center (from 2013).
    Stakeholders’ Perspectives on Malleable Signatures in a Cloud-based eHealth Scenario2016In: Proceedings of the International Symposium on Human Aspects of Information Security & Assurance / [ed] Nathan Clarke & Steven Furnell, 2016, p. 220-230Conference paper (Refereed)
    Abstract [en]

    In this paper, we discuss end user requirements that we elicited for the use of malleable signatures in a Cloud-based eHealth scenario. The concept of a malleable signature, which is a privacy enhancing cryptographic scheme that enables the redaction of personal information from signed documents while preserving the validity of the signature, might be counter- intuitive to end users as its functionality does not correspond to the one of a traditional signature scheme. A qualitative study via a series of semi-structured interviews and focus groups has been conducted to understand stakeholders’ opinions and concerns in regards to the possible applications of malleable signatures in the eHealth area, where a medical record is first digitally signed by a doctor and later redacted by the patient in the cloud. Results from this study yielded user requirements such as the need for suitable metaphors and guidelines, usable templates, and clear redaction policies. 

  • 119.
    Alavian-Ghavanini, Ali
    et al.
    Karolinska Institutet.
    Lin, Ping-I
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Health Sciences (from 2013).
    Lind, P. Monica
    Uppsala University.
    Rimfors, Sabina Risen
    Karolinska Institutet.
    Lejonklou, Margareta Halin
    Uppsala University.
    Dunder, Linda
    Uppsala University.
    Tang, Mandy
    Karolinska Institutet.
    Lindh, Christian
    Lund University.
    Bornehag, Carl-Gustaf
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Health Sciences (from 2013). Icahn School of Medicine Mt Sinai, New York, USA.
    Rueegg, Joelle
    Karolinska Institutet.
    Prenatal Bisphenol A Exposure is Linked to Epigenetic Changes in Glutamate Receptor Subunit Gene Grin2b in Female Rats and Humans2018In: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 8, article id 11315Article in journal (Refereed)
    Abstract [en]

    Bisphenol A (BPA) exposure has been linked to neurodevelopmental disorders and to effects on epigenetic regulation, such as DNA methylation, at genes involved in brain function. High doses of BPA have been shown to change expression and regulation of one such gene, Grin2b, in mice. Yet, if such changes occur at relevant doses in animals and humans has not been addressed. We investigated if low-dose developmental BPA exposure affects DNA methylation and expression of Grin2b in brains of adult rats. Furthermore, we assessed associations between prenatal BPA exposure and Grin2b methylation in 7-year old children. We found that Grin2b mRNA expression was increased and DNA methylation decreased in female, but not in male rats. In humans, prenatal BPA exposure was associated with increased methylation levels in girls. Additionally, Iow APGAR scores, a predictor for increased risk for neurodevelopmental diseases, were associated with higher Grin2b methylation levels in girls. Thus, we could link developmental BPA exposure and Iow APGAR scores to changes in the epigenetic regulation of Grin2b, a gene important for neuronal function, in a sexual dimorphic fashion. Discrepancies in exact locations and directions of the DNA methylation change might reflect differences between species, analysed tissues, exposure level and/or timing.

  • 120.
    Alay, Özgü
    et al.
    Simula Research Laboratory, Norway.
    Lutu, Andra
    Simula Research Laboratory, Norway.
    García, Rafael
    IMDEA Networks Institute, Spain.
    Peón Quirós, Miguel
    IMDEA Networks Institute, Spain.
    Mancuso, Vincenzo
    IMDEA Networks Institute, Spain.
    Hirsch, Thomas
    Celerway AS, Norway.
    Dely, Tobias
    Celerway AS, Norway.
    Werme, Jonas
    Celerway AS, Norway.
    Evensen, Kristian
    Celerway AS, Norway.
    Hansen, Audun
    Celerway AS, Norway.
    Alfredsson, Stefan
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Karlsson, Jonas
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Brunström, Anna
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Safari Khatouni, Ali
    Politecnico di Torino.
    Mellia, Marco
    Politecnico di Torino.
    Ajmone Marsan, Marco
    Politecnico di Torino.
    Monno, Roberto
    Nextworks, Italy.
    Lønsethagen, Håkon
    Telenor R&D, Norway.
    MONROE, a distributed platform to measure and assess mobile broadband networks: demo2016In: Proceedings of the Tenth ACM International Workshop on Wireless Network Testbeds, Experimental Evaluation, and Characterization, New York, NY, USA: Association for Computing Machinery (ACM), 2016, p. 85-86Conference paper (Refereed)
    Abstract [en]

    This demo presents the MONROE distributed platform and how it can be used to implement measurement and assessment experiments with operational mobile broadband networks (MBBs). MONROE provides registered experimenters with open access to hundreds of nodes, distributed over several European countries and equipped with multiple MBB connections, and a backend system that collects the measurement results. Experiments are scheduled through a user-friendly web client, with no need to directly access the nodes. The platform further embeds tools for real-time traffic flow analysis and a powerful visualization tool.

  • 121.
    Alay, Özgü
    et al.
    Simula Research Laboratory, Norway.
    Lutu, Andra
    Simula Research Laboratory, Norway.
    Peón-Quirós, Miguel
    IMDEA Networks Institute, Spain.
    Mancuso, Vincenzo
    IMDEA Networks Institute, Spain.
    Hirsch, Thomas
    Celerway Communications, Norway.
    Evensen, Kristian
    Celerway Communications, Norway.
    Hansen, Audun
    Celerway Communications, Norway.
    Alfredsson, Stefan
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Karlsson, Jonas
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Brunström, Anna
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Safari Khatouni, Ali
    Politecnico di Torino, Italy.
    Mellia, Marco
    Politecnico di Torino, Italy.
    Ajmone Marsan, Marco
    IMDEA Networks Institute, Spain and Politecnico di Torino, Italy.
    Experience: An open platform for experimentation with commercial mobile broadband networks2017In: MobiCom '17 Proceedings of the 23rd Annual International Conference on Mobile Computing and Networking, New York: Association for Computing Machinery (ACM), 2017, p. 70-78Conference paper (Refereed)
    Abstract [en]

    Open experimentation with operational Mobile Broadband (MBB) networks in the wild is currently a fundamental requirement of the research community in its endeavor to address the need of innovative solutions for mobile communications. Even more, there is a strong need for objective data about stability and performance of MBB (e.g., 3G/4G) networks, and for tools that rigorously and scientifically assess their status. In this paper, we introduce the MONROE measurement platform: an open access and flexible hardware-based platform for measurements and custom experimentation on operational MBB networks. The MONROE platform enables accurate, realistic and meaningful assessment of the performance and reliability of 11 MBB networks in Europe. We report on our experience designing, implementing and testing the solution we propose for the platform. We detail the challenges we overcame while building and testing the MONROE testbed and argue our design and implementation choices accordingly. We describe and exemplify the capabilities of the platform and the wide variety of experiments that external users already perform using the system

  • 122.
    Alay, Özgü
    et al.
    Simula Research Laboratory, Norway.
    Lutu, Andra
    Simula Research Laboratory, Norway.
    Rafael, García
    IMDEA Networks Institute, Spain.
    Peón Quirós, Miguel
    IMDEA Networks Institute, Spain.
    Mancuso, Vincenzo
    IMDEA Networks Institute, Spain.
    Hirsch, Thomas
    Celerway AS, Norway.
    Tobias, Dély
    Celerway AS, Norway.
    Werme, Jonas
    Celerway AS, Norway.
    Evensen, Kristian
    Celerway AS, Norway.
    Fosselie Hansen, Audun
    Celerway AS, Norway.
    Alfredsson, Stefan
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Karlsson, Jonas
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Brunström, Anna
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Safari Khatouni, Ali
    Politecnico di Torino, Italy.
    Mellia, Marco
    Politecnico di Torino, Italy.
    Ajmone Marsan, Marco
    Politecnico di Torino & IMDEA Networks, Italy.
    Monno, Roberto
    Nextworks, Italy.
    Lønsethagen, Håkon
    Telenor R&D, Norway.
    Measuring and Assessing Mobile Broadband Networks with MONROE2016In: 2016 IEEE International Symposium on a World of Wireless, Mobile, and Multimedia Networks (WoWMoM), Red Hook: IEEE, 2016Conference paper (Refereed)
    Abstract [en]

    Mobile broadband (MBB) networks underpin numerous vital operations of the society and are arguably becoming the most important piece of the communications infrastructure. In this demo paper, our goal is to showcase the potential of a novel multi-homed MBB platform for measuring, monitoring and assessing the performance of MBB services in an objective manner. Our platform, MONROE, is composed of hundreds of nodes scattered over four European countries and a backend system that collects the measurement results. Through a user-friendly web client, the experimenters can schedule and deploy their experiments. The platform further embeds traffic analysis tools for real-time traffic flow analysis and a powerful visualization tool.

  • 123.
    Al-Azzawi, Tahreer
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Health Sciences.
    En undersökning av antibiotikaförskrivning till patienter med okomplicerad faryngotonsillit inom primärvården.: En enkätundersökning på en vårdcentral i Värmland.2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
  • 124.
    Albertsson, Hanna
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Health Sciences (from 2013).
    Guttke, Ida
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Health Sciences (from 2013).
    Faktorer som påverkardistriktssköterskans hälsosamtal med barn: En systematisk litteraturstudie2019Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
  • 125.
    Aldaz, J. M.
    et al.
    Univ Autonoma Madrid, ICMAT, E-28049 Madrid, Spain.;Univ Autonoma Madrid, Dept Matemat, E-28049 Madrid, Spain..
    Barza, Sorina
    Karlstad University, Faculty of Technology and Science, Department of Mathematics.
    Fujii, M.
    Osaka Kyoiku Univ, Dept Math, Kashiwara, Osaka 5828582, Japan..
    Moslehian, Mohammad Sal
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science.
    Advances in Operator Cauchy-Schwarz Inequalities and their Reverses2015In: Annals of Functional Analysis, ISSN 2008-8752, E-ISSN 2008-8752, Vol. 6, no 3, p. 275-295Article in journal (Refereed)
    Abstract [en]

    The Cauchy-Schwarz (C-S) inequality is one of the most famous inequalities in mathematics. In this survey article, we first give a brief history of the inequality. Afterward, we present the C-S inequality for inner product spaces. Focusing on operator inequalities, we then review some significant recent developments of the C-S inequality and its reverses for Hilbert space operators and elements of Hilbert C*-modules. In particular, we pay special attention to an operator Wielandt inequality.

  • 126.
    Aldrin-Kirk, Fredrick
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    The Choice: An examination of young peoples commuting habits2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
  • 127.
    Aldzic, Almir
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Läraren får gärna också visa mer hur man ska göra": En studie av årskurs nio elevers inställning till idrott samt idrott och hälsa och deras uppfattning kring ämnets innehåll och arbetssätt.2014Independent thesis Advanced level (professional degree), 10 credits / 15 HE creditsStudent thesis
  • 128.
    Alex, Alexeev
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Katrin, Johansson
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Riskfaktorer som kan påverka patientsäkerheten när sjuksköterskor upplever arbetsrelaterad stress: En litteraturstudie2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Introduktion: Patientsäkerhet har en betydande roll i omvårdnaden och baseras på att skydda patienten från vårdskador. Årligen drabbas upp till 100 000 personer i Sverige av vårdskador, och vårdskador drabbar patienter dagligen. I den moderna omvårdnaden hanterar sköterskorna dagligen stress, som orsakas av stressfaktorer som påverkar sjuksköterskornas utförande av patientsäker vård. Syfte: Litteraturstudiens syfte var att beskriva riskfaktorer som kan påverka patientsäkerheten när sjuksköterskor upplever arbetsrelaterad stress. Metod: Litteraturstudiens grundades på Polit och Becks (2012) niostegsmodell med ett induktivt arbetssätt. Efter urval framkom det 13 artiklar som var relevanta för studien. Efter granskningen av artiklar skapades tre huvudkategorier och en underkategori. Resultat: Litteraturstudiens resultat visas i tre huvudkategorier och en underkategori av riskfaktorer som kan påverka patientsäkerheten negativt. Dessa kategorier var Arbetsbelastning, med underkategorin Tidsbrist, Avbrott i arbetet samt Kommunikation och samarbete. Resultatet visade att många sjuksköterskor upplever höga nivåer av utmattning och utbrändhet, vilket kan påverka patientsäkerheten negativt. Slutsats: När sjuksköterskor upplever arbetsrelaterad stress finns det flera riskfaktorer som kan leda till misstag och vårdskador. Dessa riskfaktorer kan leda till att den arbetsrelaterade stressen ökar, vilket kan leda till ökad utmattning, missnöje samt att sjuksköterskorna slutar på sitt arbete. Arbetsrelaterad stress och riskfaktorer som upplevs av sjuksköterskor på arbetsplatsen ökar även risker för att begå flera misstag och orsakar flera vårdskador som egentligen kunde undvikas.

  • 129.
    Alexandersson, Jenny
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Förändring av layout och produktionsflöde: Med fokus på förbättringar och struktur i produktionen2018Independent thesis Basic level (degree of Bachelor), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    This project has been implemented as a degree of Bachelor of Science in Innovation and Design at the Faculty of Health, Science and Technology at the University of Karlstad. The project started in November 2017 and continued to May 2018.

    The most of the work has been performed on the company KD: Solskydd AB in Degerfors. The main task of this project was to develop a new flow-oriented factory layout, to one of the departments in the company. The work included many observations and interviews, it was a big part of the specification and preliminary study. The analysis part of the project was to investigate the possibilities to a better flow in the production and opportunities for improvement in the factory. The methods that were used in this project were establish in Lean.

    From the product development process strategy have a project can be formed and performed. The process has been adapted to this project.

    Ten separate ideas of layouts were made. Each idea fulfilled the specification different. A group of selected co-workers from the compony and some of the persons in the board of the company, got a presentation of the ten ideas. The group discussed the separate ideas from the information they have of the ideas, from that they select one of the layout ideas. To be the one!

    A simulation of the new layout was performed in Karlstad Lean Factory. Nine employees from the company participated in the simulation. The simulation helped the co-workers to see improvements in the production flow.

    In the end of the project investigated the possibilities to more improvement areas in the company, with help from Lean.

  • 130.
    Alfredsson, Elin
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Health Sciences.
    Axelsson, Emma
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Health Sciences.
    Att leva med fatigue vid cancersjukdom- ur ett patientperspektiv: En litteraturstudie2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

     Introduktion: Cancer är den andra vanligaste dödsorsaken i Sverige. Cancer drabbar alla åldersgrupper men är vanligare bland äldre. De tre vanligaste behandlingsmetoderna för cancer är strålning, cytostatika och kirurgi. Den vanligaste biverkningen är cancerrelaterad fatigue. Livskvalitet som påverkas definieras som en individs inställning till livet i relation till deras mål, förväntningar, normer och bekymmer. Syfte: Syftet med studien var att belysa patienters upplevelser av cancerrelaterad fatigue och hur den påverkar deras livssituation samt livskvalitet. Metod: Litteraturstudien genomfördes enligt Polit och Becks (2017) nio steg. Tio vetenskapliga artiklar valdes ut efter sökningar gjorda i databaserna CINAHL och PubMed, dessa artiklar presenteras i en artikelmatris (bilaga 1). Artiklarna som användes till studiens resultatdel var fem stycken kvantitativa, fyra stycken kvalitativa och en med mixad metod. Resultat: Utifrån det insamlade materialet utarbetades fem teman som svarade på patienternas upplevelser av cancerrelaterad fatigue och hur livssituationen påverkas samt livskvalitet. Dessa fem teman var värdelöshet/hopplöshet, ensamhet/inte känna sig förstådd, orkeslöshet/kroppslig svaghet, irritation/frustration, och förståelse/acceptans. Slutats: Cancerrelaterad fatigue påverkar patienternas hela tillvaro och hur det upplever olika aspekter i livet. De upplever en förändrad livssituation och att livskvaliteten påverkas negativt. Cancerrelaterad fatigue är ett symtom som påverkar alla patienter på något vis men alla drabbas inte lika hårt. Cancerrelaterad fatigue kan ses som ett holistiskt fenomen med mycket stor komplexitet. 

  • 131.
    Alfredsson, Stefan
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science.
    A Case Study of Recent Mifare Classic Field Deployments From an (In-)Security Perspective2013In: Proceedings of the 21st International Conference on Software, Telecommunications and Computer Networks (SoftCOM 2013), Split, Croatia: FESB, University of Split , 2013Conference paper (Refereed)
    Abstract [en]

    Mifare Classic is a very popular near-field communication technology that provides a shared-key, access-controlled, storage. Although the authentication protocol of Mifare Classic is compromised since half a decade, systems are still being deployed based on this technology, e.g. for access control systems and for public transport ticketing. By using commodity hardware, such as NFC enabled smartphones, by passing the security measures in some cases only require the installation and operation of a smartphone app. To this end, we present case studies of a number of recent Mifare Classic systems deployed during the last year, to serve as an illustration of practical security problems and to raise awareness thereof among NFC technology buyers and system implementors.

  • 132.
    Alfredsson, Stefan
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science.
    Del Giudice, Giacomo
    Politecnico di Bari, Italy.
    Garcia, Johan
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science.
    Brunstrom, Anna
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science.
    De Cicco, Luca
    Ecole superieure d'Electricite, France; Politecnico di Bari, Italy.
    Mascolo, Saverio
    Politecnico di Bari, Italy.
    Impact of TCP Congestion Control on Bufferbloat in Cellular Networks2013In: Proceedings of the 14th IEEE International Symposium on a World of Wireless, Mobile and Multimedia Networks (WoWMoM 2013) / [ed] Angelos Lazaris, Balaji Rengarajan, IEEE Press, 2013Conference paper (Refereed)
    Abstract [en]

    The existence of excessively large and too filled network buffers, known as bufferbloat, has recently gained attention as a major performance problem for delay-sensitive applications. One important network scenario where bufferbloat may occur is cellular networks.

    This paper investigates the interaction between TCP congestion control and buffering in cellular networks. Extensive measurements have been performed in commercial 3G, 3.5G and 4G cellular networks, with a mix of long and short TCP flows using the CUBIC, NewReno and Westwood+ congestion control algorithms. The results show that the completion times of short flows increase significantly when concurrent long flow traffic is introduced. This is caused by increased buffer occupancy from the long flows. In addition, for 3G and 3.5G the completion times are shown to depend significantly on the congestion control algorithms used for the background flows, with CUBIC leading to significantly larger completion times.

  • 133.
    Alfredsson, Stefan
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science.
    Del Giudice, Giacomo
    Politecnico di Bari, Italy.
    Garcia, Johan
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science.
    Brunstrom, Anna
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science.
    De Cicco, Luca
    Ecole superieure d'Electricite, France; Politecnico di Bari, Italy.
    Mascolo, Saverio
    Politecnico di Bari, Italy.
    Observations of Bufferbloat in Swedish Cellular Networks2013In: Proceedings of the 9th Swedish National Computer Networking Workshop (SNCNW 2013) / [ed] Bengt Ahlgren, 2013Conference paper (Refereed)
  • 134.
    Alfredsson, Svante
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Konceptutveckling av transportlösning för kaffeutrustning till event2016Independent thesis Basic level (university diploma), 180 HE creditsStudent thesis
    Abstract [en]

    This thesis is done during the spring semester 2016 for the Bachelor of Science in Innovation and Design programme at Karlstad University. The mission of the thesis was provided by the company 3TEMP AB in Arvika.

    In order to serve large quantities of coffee at big events, festivals and fairs a powerful coffee machine is required. Due to its size the machine is difficult handle during transport. This project is about finding a solution that makes the transport of the coffee machine and its related equipment safer and easier to handle during transportation between events.

    The goal of the project was to find a possible solution that makes the transportation of the equipment more efficient and ergonomic. In order to find as many ideas as possible the design process has been used. This includes a research followed by an ideation, concept development and concept evaluation. The project ended with one concept presented in the form of a layout design in CAD together with assembly drawings, sketches and a model.

    In this project interviews and observations has been done together with the people who transport coffee equipment on a daily basis. The results of the observations were later compared with the recommended lifting weight for manual lifting tasks using NOISH lifting equation. In the event business different types of vehicles are used to transport equipment at the event areas. Everything from ATVs and snowmobiles to tractors and caterpillar vehicles are used. In the project there has been a search for a common denominator between those vehicles.

    During the project benchmarking of similar products has also been done to find inspiration for new ideas. To further evaluate the concepts an examination of laws and regulations for transportation of equipment in traffic and off-road has been done.

    The equipment also has to withstand long distance transport by rail, road, sea and air. To meet these requirements interviews were made with the company MariTerm AB who works with educating in cargo securing of goods for worldwide shipment.

  • 135.
    AL-Gerty, Asra
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Distriktssköterskan och telefonrådgivningen: En litteraturstudie2018Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Introduction : The district nurse makes assessment, refers and provides advice, support and information to the public in telephone consulting. Telephone counseling is a growing part of healthcare and is a complex area of health care, where district nurses encounter many new situations and challenges. District nurses offer self-care to the public in telephone counseling.

    Aim: To identify which factors create opportunities and provide limitations, there is a district nurse's task in telephone counseling in primary care.

    Method: A systematic literature study with descriptive synthesis based on nine scientific articles published 2008-2018. The articles were searched in databases PubMed and Cinahl. The articles were processed with qualitative content analysis.

    Result: Nurses thought it was exhaustive to assess and handle conversations appropriately. Communication skills should be highly developed in the telephone-based meetings. The cognitive fatigue caused the nurse to fail to listen to the caller and led to the nurse asking too few questions. Nurses perceived that computerized decision support was both positive and negative.

    Conclusion: Nurses thought the decision support system was complementary support, it was perceived as a valuable source of information. Communication skills are a very important tool in telephone consulting. Cognitive fatigue due to long workouts had a major impact on the nurses' assessment.

  • 136.
    Al-Grety, Sheima
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Tid och klockan i läromedel: En läromedelsanalys med fokus på de matematiska förmågorna och representationsformer2019Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The purpose of the study was to analyse time and clock and its progression in textbooks, for grades 4–6. The study also aimed, based on tasks linked to clock and time, to analyse which representation forms and mathematical competencies are trained in the selected textbooks. To studying as well as analysing different mathematics teaching textbooks, a document and textbook analysis was used to build up the approach for the study.

    The results of the study showed that in the selected teaching materials, a mixture of the forms of representation, however, often lacked a concrete model. Concrete model existed in a few single tasks. The study's results also show that students are given the opportunity to practice the five mathematical skills but to varying extents. Communication and reasoning ability are the skills that are least trained in teaching materials.

    The conclusion that can be drawn is that the role of teachers in the use of teaching materials in mathematics is of great im-portance because certain abilities are highlighted more in the workbook. The use of different representations might help the student to get good knowledge about time and the clock. Another conclusion is that the reasoning ability and communication skills need to be lifted more, so that students can learn to reason and communicate with each other.

  • 137.
    Alho, Artur
    et al.
    Univ Lisbon, Ctr Math Anal Geometry & Dynam Syst, Inst Super Tecn, Av Rovisco Pais, P-1049001 Lisbon, Portugal..
    Carloni, Sante
    Univ Lisbon, Ctr Multidisciplinar Astrofis CENTRA, Inst Super Tecn, Av Rovisco Pais, P-1049001 Lisbon, Portugal..
    Uggla, Claes
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics (from 2013).
    On dynamical systems approaches and methods in f (R) cosmology2016In: Journal of Cosmology and Astroparticle Physics, ISSN 1475-7516, E-ISSN 1475-7516, no 8, article id 064Article in journal (Refereed)
    Abstract [en]

    We discuss dynamical systems approaches and methods applied to flat Robertson Walker models in f(R)-gravity. We argue that a complete description of the solution space of a model requires a global state space analysis that motivates globally covering state space adapted variables. This is shown explicitly by an illustrative example, f(R) = R + alpha R-2, alpha > 0, for which we introduce new regular dynamical systems on global compactly extended state spaces for the Jordan and Einstein frames. This example also allows us to illustrate several local and global dynamical systems techniques involving, e.g., blow ups of nilpotent fixed points, center manifold analysis, averaging, and use of monotone functions. As a result of applying dynamical systems methods to globally state space adapted dynamical systems formulations, we obtain pictures of the entire solution spaces in both the Jordan and the Einstein frames. This shows, e.g., that due to the domain of the conformal transformation between the Jordan and Einstein frames, not all the solutions in the Jordan frame are completely contained in the Einstein frame. We also make comparisons with previous dynamical systems approaches to f (R) cosmology and discuss their advantages and disadvantages.

  • 138.
    Alho, Artur
    et al.
    University of Lisbon, Portugal.
    Hell, Juliette
    Free University Berlin, Germany.
    Uggla, Claes
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics (from 2013).
    Global dynamics and asymptotics for monomial scalar field potentials and perfect fluids2015In: Classical and quantum gravity, ISSN 0264-9381, E-ISSN 1361-6382, Vol. 32, no 14, article id 145005Article in journal (Refereed)
    Abstract [en]

    We consider a minimally coupled scalar field with a monomial potential and a perfect fluid in flat Friedmann-Lemaitre-Robertson-Walker cosmology. We apply local and global dynamical systems techniques to a new three-dimensional dynamical systems reformulation of the field equations on a compact state space. This leads to a visual global description of the solution space and asymptotic behavior. At late times we employ averaging techniques to prove statements about how the relationship between the equation of state of the fluid and the monomial exponent of the scalar field affects asymptotic source dominance and asymptotic manifest self-similarity breaking. We also situate the ’attractor’ solution in the three-dimensional state space and show that it corresponds to the one-dimensional unstable center manifold of a de Sitter fixed point, located on an unphysical boundary associated with the dynamics at early times. By deriving a center manifold expansion we obtain approximate expressions for the attractor solution. We subsequently improve the accuracy and range of the approximation by means of Pade approximants and compare with the slow-roll approximation. 

  • 139.
    Alho, Artur
    et al.
    Technical University of Lisbon, Portugal.
    Uggla, Claes
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics (from 2013).
    Global dynamics and inflationary center manifold and slow-roll approximants2015In: Journal of Mathematical Physics, ISSN 0022-2488, E-ISSN 1089-7658, Vol. 56, no 1, article id 012502Article in journal (Refereed)
    Abstract [en]

    We consider the familiar problem of a minimally coupled scalar field with quadratic potential in flat Friedmann-Lemaître-Robertson-Walker cosmology to illustrate a number of techniques and tools, which can be applied to a wide range of scalar field potentials and problems in, e.g., modified gravity. We present a global and regular dynamical systems description that yields a global understanding of the solution space, including asymptotic features. We introduce dynamical systems techniques such as center manifold expansions and use Padé approximants to obtain improved approximations for the “attractor solution” at early times. We also show that future asymptotic behavior is associated with a limit cycle, which shows that manifest self-similarity is asymptotically broken toward the future and gives approximate expressions for this behavior. We then combine these results to obtain global approximations for the attractor solution, which, e.g., might be used in the context of global measures. In addition, we elucidate the connection between slow-roll based approximations and the attractor solution, and compare these approximations with the center manifold based approximants.

  • 140.
    Alho, Artur
    et al.
    Center for Mathematical Analysis, Geometry and Dynamical Systems, Instituto Superior Técnico, Universidade de Lisboa, Portugal.
    Uggla, Claes
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics (from 2013).
    Inflationary alpha-attractor cosmology: A global dynamical systems perspective2017In: Physical Review D: covering particles, fields, gravitation, and cosmology, ISSN 2470-0010, E-ISSN 2470-0029, Vol. 95, no 8, article id 083517Article in journal (Refereed)
    Abstract [en]

    We study flat Friedmann-Lemaitre-Robertson-Walker alpha-attractor E- and T-models by introducing a dynamical systems framework that yields regularized unconstrained field equations on two-dimensional compact state spaces. This results in both illustrative figures and a complete description of the entire solution spaces of these models, including asymptotics. In particular, it is shown that observational viability, which requires a sufficient number of e-folds, is associated with a particular solution given by a one-dimensional center manifold of a past asymptotic de Sitter state, where the center manifold structure also explains why nearby solutions are attracted to this "inflationary attractor solution." A center manifold expansion yields a description of the inflationary regime with arbitrary analytic accuracy, where the slow-roll approximation asymptotically describes the tangency condition of the center manifold at the asymptotic de Sitter state.

  • 141.
    Alho, Artur
    et al.
    Univ Lisbon, Inst Super Tecn, Ctr Math Anal Geometry & Dynam Syst, P-1049001 Lisbon, Portugal..
    Uggla, Claes
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics.
    Scalar field deformations of Lambda CDM cosmology2015In: Physical Review D, ISSN 1550-7998, E-ISSN 1550-2368, Vol. 92, no 10, article id 103502Article in journal (Refereed)
    Abstract [en]

    This paper treats nonrelativistic matter and a scalar field phi with a monotonically decreasing potential minimally coupled to gravity in flat Friedmann-Lemaitre-Robertson-Walker cosmology. The field equations are reformulated as a three-dimensional dynamical system on an extended compact state space, complemented with cosmographic diagrams. A dynamical systems analysis provides global dynamical results describing possible asymptotic behavior. It is shown that one should impose global and asymptotic bounds on lambda = -V-1 dV/d phi to obtain viable cosmological models that continuously deform Lambda CDM cosmology. In particular we introduce a regularized inverse power-law potential as a simple specific example.

  • 142.
    Alho, Artur
    et al.
    Univ Lisbon, Portugal..
    Uggla, Claes
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics (from 2013).
    Wainwright, John
    Univ Waterloo, Canada..
    Perturbations of the Lambda-CDM model in a dynamical systems perspective2019In: Journal of Cosmology and Astroparticle Physics, ISSN 1475-7516, E-ISSN 1475-7516, no 9, article id 045Article in journal (Refereed)
    Abstract [en]

    The observational success and simplicity of the ACDM model, and the explicit analytic perturbations thereof, set the standard for any alternative cosmology. It therefore serves as a comparison ground and as a test case for methods which can be extended and applied to other cosmological models. In this paper we introduce dynamical systems and methods to describe linear scalar and tensor perturbations of the ACDM model, which serve as pedagogical examples that show the global illustrative powers of dynamical systems in the context of cosmological perturbations. We also study the asymptotic properties of the shear and Weyl tensors and discuss the validity of the perturbations as approximations to the Einstein field equations. Furthermore, we give a new approximation for the linear growth 5 rate, f (z) = d ln delta/d ln a = Omega(6/11)(m) - 1/70(1-Omega(m))(5/2), where z is the cosmological redshift, Omega(m) = Omega(m)(z), while a is the background scale factor, and show that it is much more accurate than the previous ones in the literature.

  • 143.
    Ali, Asad A.
    et al.
    Univ Michigan, Dept Aerosp Engn, Ann Arbor, MI 48109 USA..
    Hoagg, Jesse B.
    Univ Kentucky, Dept Mech Engn, 151 Ralph G Anderson Bldg, Lexington, KY 40507 USA..
    Mossberg, Magnus
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics.
    Bernstein, Dennis S.
    Univ Michigan, Dept Aerosp Engn, Ann Arbor, MI 48109 USA..
    On the stability and convergence of a sliding-window variable-regularization recursive-least-squares algorithm2016In: International journal of adaptive control and signal processing (Print), ISSN 0890-6327, E-ISSN 1099-1115, Vol. 30, no 5, p. 715-735Article in journal (Refereed)
    Abstract [en]

    A sliding-window variable-regularization recursive-least-squares algorithm is derived, and its convergence properties, computational complexity, and numerical stability are analyzed. The algorithm operates on a finite data window and allows for time-varying regularization in the weighting and the difference between estimates. Numerical examples are provided to compare the performance of this technique with the least mean squares and affine projection algorithms. Copyright (c) 2015 John Wiley & Sons, Ltd.

  • 144.
    Ali, Nour
    et al.
    Brunel University, London, UK.
    Baker, Sean
    University of Limerick, Ireland.
    O’Crowley, Ross
    Red Orkid Limited, Dublin, Ireland.
    Herold, Sebastian
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Buckley, Jim
    University of Limerick, Ireland.
    Architecture consistency: State of the practice, challenges and requirements2018In: Journal of Empirical Software Engineering, ISSN 1382-3256, E-ISSN 1573-7616, Vol. 23, no 1, p. 224-258Article in journal (Refereed)
    Abstract [en]

    Architecture Consistency (AC) aims to align implemented systems with their intended architectures. Several AC approaches and tools have been proposed and empirically evaluated, suggesting favourable results. In this paper, we empirically examine the state of practice with respect to Architecture Consistency, through interviews with nineteen experienced software engineers. Our goal is to identify 1) any practises that the companies these architects work for, currently undertake to achieve AC; 2) any barriers to undertaking explicit AC approaches in these companies; 3) software development situations where practitioners perceive AC approaches would be useful, and 4) AC tool needs, as perceived by practitioners. We also assess current commercial AC tool offerings in terms of these perceived needs. The study reveals that many practitioners apply informal AC approaches as there are barriers for adopting more formal and explicit approaches. These barriers are: 1) Difficulty in quantifying architectural inconsistency effects, and thus justifying the allocation of resources to fix them to senior management, 2) The near invisibility of architectural inconsistency to customers, 3) Practitioners’ reluctance towards fixing architectural inconsistencies, and 4) Practitioners perception that huge effort is required to map the system to the architecture when using more formal AC approaches and tools. Practitioners still believe that AC would be useful in supporting several of the software development activities such as auditing, evolution and ensuring quality attributes. After reviewing several commercial tools, we posit that AC tool vendors need to work on their ability to support analysis of systems made up of different technologies, that AC tools need to enhance their capabilities with respect to artefacts such as services and meta-data, and to focus more on non-maintainability architectural concerns.

  • 145.
    Ali, Nour
    et al.
    Brunel University, London, UK.
    Baker, Sean
    University of Limerick, Ireland.
    O'Crowley, Ross
    Red Orkid Limited, Dublin, Ireland.
    Herold, Sebastian
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Buckley, Jim
    University of Limerick, Ireland.
    Architecture consistency: State of the practice, challenges and requirements (vol 23, pg 224, 2018)2018In: Journal of Empirical Software Engineering, ISSN 1382-3256, E-ISSN 1573-7616, Vol. 23, no 3, p. 1868-1869Article in journal (Refereed)
  • 146.
    Ali, Susan
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Health Sciences (from 2013).
    Får män dyrare och nyare läkemedel än kvinnor?: En intervjustudie om läkemedelsskillnader mellan män och kvinnor och mellan socioekonomiska grupper i samhället2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
  • 147.
    Alipour, Farah
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Health Sciences.
    Studier av effekter av epigallokatekingallat och extrakt av grönt te och kråkbär på enzymer involverade i prostaglandin bildning i humana monocyter och makrofager2014Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
  • 148.
    Alizadeh Noghani, Kyoomars
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Service Migration in Virtualized Data Centers2020Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Modern virtualized Data Centers (DCs) require efficient management techniques to guarantee high quality services while reducing their economical cost. The ability to live migrate virtual instances, e.g., Virtual Machines (VMs), both inside and among DCs is a key operation for the majority of DC management tasks that brings significant flexibility into the DC infrastructure. However, live migration introduces new challenges as it ought to be fast and seamless while at the same time imposing a minimum overhead on the network. In this thesis, we study the networking problems of live service migration in modern DCs when services are deployed in virtualized environments, e.g., VMs and containers. In particular, this thesis has the following main objectives: (1) improving the live VM migration in Software-Defined Network (SDN) enabled DCs by addressing networking challenges of live VM migration, and (2) investigating the trade-off between the reconfiguration cost and optimality of the Service Function Chains (SFCs) placement after the reconfiguration has been applied when SFCs are composed of stateful Virtual Network Functions (VNFs).

    To achieve the first objective, in this thesis, we use distinctive characteristics of SDN architectures such as their centralized control over the network to accelerate the network convergence time and address suboptimal routing problem. Consequently, we enhance the quality of intra- and inter-DC live migrations. Furthermore, we develop an SDN-based framework to improve the inter-DC live VM migration by automating the deployment, improving the management, enhancing the performance, and increasing the scalability of interconnections among DCs.

    To accomplish the second objective, we investigate the overhead of dynamic reconfiguration of stateful VNFs. Dynamic reconfiguration of VNFs is frequently required in various circumstances, and live migration of VNFs is an integral part of this operation. By mathematically formulating the reconfiguration costs of stateful VNFs and developing a multi-objective heuristic solution, we explore the trade-off between the reconfiguration cost required to improve a given placement and the degree of optimality achieved after the reconfiguration is performed. Results show that the cost of performing the reconfiguration operations required to realize an optimal VNF placement might hamper the gain that could be achieved.

  • 149.
    Alizadeh Noghani, Kyoomars
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Towards Seamless Live Migration in SDN-Based Data Centers2018Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Live migration of Virtual Machines (VMs) has significantly improved the flexibility of modern Data Centers (DCs). Ideally, live migration ought to be seamless which in turn raises challenges on how to minimize service disruption and avoid performance degradation. To address these challenges, a comprehensive support from the underlying network is required. However, legacy DC networks fall short to help as they take a reactive approach to live migration procedure. Moreover, the complexity and inflexibility of legacy DC networks make it difficult to deploy, manage, and improve network technologies that DC providers may need to use for migration.

    In this thesis, we explore the application of Software Defined Networking (SDN) paradigm for making live VM migration more seamless. Exploiting the characteristics of SDN such as its centralized view on network states, we contribute to the body of knowledge by enhancing the quality of intra- and inter-DC live migration. Firstly, for intra-DC migration, we provide an SDN-based solution which minimizes the service disruption by employing OpenFlow-based resiliency mechanisms to prepare a DC network for migration proactively. Secondly, we improve the inter-DC live migration by accelerating the network convergence through announcing the migration in the control plane using MP-BGP protocol. Further, our proposed framework resolves the sub-optimal routing problem by conducting the gateway functionality at the SDN controller. Finally, with the ultimate goal of improving the inter-DC migration, we develop an SDN-based framework which automates the deployment, improves the management, enhances the performance, and increases the scalability of interconnections among DCs.

  • 150.
    Alizadeh Noghani, Kyoomars
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Ghazzai, Hakim
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Kassler, Andreas
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    A Generic Framework for Task Offloading in mmWave MEC Backhaul Networks2018In: 2018 IEEE Global Communications Conference (GLOBECOM), IEEE, 2018, p. 1-7Conference paper (Refereed)
    Abstract [en]

    With the emergence of millimeter-Wave (mmWave) communication technology, the capacity of mobile backhaul networks can be significantly increased. On the other hand, Mobile Edge Computing (MEC) provides an appropriate infrastructure to offload latency-sensitive tasks. However, the amount of resources in MEC servers is typically limited. Therefore, it is important to intelligently manage the MEC task offloading by optimizing the backhaul bandwidth and edge server resource allocation in order to decrease the overall latency of the offloaded tasks. This paper investigates the task allocation problem in MEC environment, where the mmWave technology is used in the backhaul network. We formulate a Mixed Integer NonLinear Programming (MINLP) problem with the goal to minimize the total task serving time. Its objective is to determine an optimized network topology, identify which server is used to process a given offloaded task, find the path of each user task, and determine the allocated bandwidth to each task on mmWave backhaul links. Because the problem is difficult to solve, we develop a two-step approach. First, a Mixed Integer Linear Program (MILP) determining the network topology and the routing paths is optimally solved. Then, the fractions of bandwidth allocated to each user task are optimized by solving a quasi-convex problem. Numerical results illustrate the obtained topology and routing paths for selected scenarios and show that optimizing the bandwidth allocation significantly improves the total serving time, particularly for bandwidth-intensive tasks.

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