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  • 1.
    Aaberg, Oddveig Reiersdal
    et al.
    Norwegian Univ Sci & Technol, Dept Hlth Sci, Fac Med & Hlth Sci, Teknologivegen 22, N-2815 Gjovik, Norway.;Univ Stavanger, Dept Qual & Hlth Technol, Fac Hlth Sci, Stavanger, Norway.;Univ Agder, Fac Hlth & Sport Sci, Dept Hlth & Nursing Sci, Norway..
    Ballangrud, Randi
    Norwegian Univ Sci & Technol, Dept Hlth Sci, Fac Med & Hlth Sci, Teknologivegen 22, N-2815 Gjovik, Norway..
    Husebo, Sissel Iren Eikeland
    Univ Stavanger, Dept Qual & Hlth Technol, Fac Hlth Sci, Stavanger, Norway.;Stavanger Univ Hosp, Gerd Ragna Bloch Thorsens Gate 8, N-4011 Stavanger, Norway..
    Hall-Lord, Marie Louise
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Health Sciences (from 2013).
    An interprofessional team training intervention with an implementation phase in a surgical ward: A controlled quasi-experimental study2019In: Journal of Interprofessional Care, ISSN 1356-1820, E-ISSN 1469-9567, p. 1-10Article in journal (Refereed)
    Abstract [en]

    Despite a growing awareness of the importance of interprofessional teamwork in relation to patient safety, many hospital units lack effective teamwork. The aim of this study was to explore if an interprofessional teamwork intervention in a surgical ward changed the healthcare personnel's perceptions of patient safety culture, perceptions of teamwork, and attitudes toward teamwork over 12 months. Healthcare personnel from surgical wards at two hospitals participated in a controlled quasi-experimental study. The intervention consisted of six hours of TeamSTEPPS team training and 12 months for the implementation of teamwork tools and strategies. The data collection was conducted among the healthcare personnel in the intervention group and the control group at baseline and at the end of the 12 month study period. The results within the intervention group showed that there were significantly improved scores in three of 12 patient safety culture dimensions and in three of five perceptions of teamwork dimensions after 12 months. When comparing between groups, significant differences were found in three patient safety culture measures in favor of the intervention group. The results of the study suggest that the teamwork intervention had a positive impact on patient safety culture and teamwork in the surgical ward.

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  • 2.
    Aaberg, Oddveig Reiersdal
    et al.
    University Agder, NOR;Norwegian University of Science & Technology, NOR ; University of Stavanger, NOR..
    Hall-Lord, Marie Louise
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Health Sciences (from 2013). Norwegian University of Science & Technology, NOR.
    Husebo, Sissel Iren Eikeland
    University Stavanger, NOR; Stavanger University Hospital, NOR .
    Ballangrud, Randi
    Norwegian University of Science & Technology, NOR.
    A human factors intervention in a hospital-evaluating the outcome of a TeamSTEPPS program in a surgical ward2021In: BMC Health Services Research, E-ISSN 1472-6963, Vol. 21, no 1, article id 114Article in journal (Refereed)
    Abstract [en]

    Background: Patient safety in hospitals is being jeopardized, since too many patients experience adverse events. Most of these adverse events arise from human factors, such as inefficient teamwork and communication failures, and the incidence of adverse events is greatest in the surgical area. Previous research has shown the effect of team training on patient safety culture and on different areas of teamwork. Limited research has investigated teamwork in surgical wards. The aim of this study was to evaluate the professional and organizational outcomes of a team training intervention among healthcare professionals in a surgical ward after 6 and 12 months. Systems Engineering Initiative for Patient Safety 2.0 was used as a conceptual framework for the study. Methods: This study had a pre-post design with measurements at baseline and after 6 and 12 months of intervention. The intervention was conducted in a urology and gastrointestinal surgery ward in Norway, and the study site was selected based on convenience and the leaders' willingness to participate in the project. Survey data from healthcare professionals were used to evaluate the intervention. The organizational outcomes were measured by the unit-based sections of the Hospital Survey of Patient Safety Culture Questionnaire, and professional outcomes were measured by the TeamSTEPPS Teamwork Perceptions Questionnaire and the Collaboration and Satisfaction about Care Decisions in Teams Questionnaire. A paired t-test, a Wilcoxon signed-rank test, a generalized linear mixed model and linear regression analysis were used to analyze the data. Results: After 6 months, improvements were found in organizational outcomes in two patient safety dimensions. After 12 months, improvements were found in both organizational and professional outcomes, and these improvements occurred in three patient safety culture dimensions and in three teamwork dimensions. Furthermore, the results showed that one of the significant improved teamwork dimensions "Mutual Support" was associated with the Patient Safety Grade, after 12 months of intervention. Conclusion: These results demonstrate that the team training program had effect after 12 months of intervention. Future studies with larger sample sizes and stronger study designs are necessary to examine the causal effect of a team training intervention in this context.

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  • 3.
    Aaberg, Oddveig Reiersdal
    et al.
    Norwegian University of Science and Technology, Norway; University of Stavanger, Norway.
    Hall-Lord, Marie Louise
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Health Sciences (from 2013). Norwegian University of Science and Technology, Norway.
    Husebo, Sissel Iren Eikeland
    University of Stavanger, Norway; Stavanger University Hospital, Norway.
    Ballangrud, Randi
    Norwegian University of Science and Technology, Norway.
    Collaboration and Satisfaction About Care Decisions in Team questionnaire: Psychometric testing of the Norwegian version, and hospital healthcare personnel perceptions across hospital units2019In: Nursing Open, E-ISSN 2054-1058, Vol. 6, no 2, p. 642-650Article in journal (Refereed)
    Abstract [en]

    Aim To translate "The Collaboration and Satisfaction About Care Decisions in Team" questionnaire (CSACD-T) into Norwegian and test it for psychometric properties. The further aim was to describe and compare healthcare personnel's collaboration and satisfaction about team decision-making (TDM) across hospital units. Design A cross-sectional study. Methods The questionnaire was translated into Norwegian. A total of 247 healthcare personnel at two hospitals responded to the questionnaire. An explorative factor analysis was performed to test the factor structure of the questionnaire, while a Cronbach's alpha analysis was used to test for internal consistency. A one-way ANOVA analysis and a Kruskal-Wallis test were applied to test for differences between hospital units. Results The results demonstrate that the Norwegian version of the CSACD-T has promising psychometric properties regarding construct validity and internal consistency. The mean score of the CSACD-T was significantly higher in the maternity ward group than in the emergency room group.

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  • 4.
    Aadalen, Sandra
    Karlstad University, Faculty of Arts and Social Sciences (starting 2013), Department of Educational Studies.
    Anpassning och differentiering av undervisning i ett klassrum för alla: Strategier för anpassning av undervisning i teori och praktik och dess effekter på elevers delaktighet2015Independent thesis Advanced level (degree of Master (One Year)), 40 credits / 60 HE creditsStudent thesis
    Abstract [en]

    This paper aims to investigate if and how instruction is adjusted or differentiated based on the conception that learners are diverse and how teacher practices are connected to contemporary research in the field. It further examines whether specific adjustments are connected to a higher rate of student participation.

    The method of the essay is an observation survey with a phenomenological approach. It includes the practices of 30 different teachers during thirty lessons at an upper secondary school in Sweden, where the majority of the students are diagnosed within the neuropsychiatric spectra. The outcome was quantitatively analyzed in SPSS.

    The study indicates that the connection between specific adjustments and student participation is a complex issue affected by several aspects and preconditions. It appears that teachers use certain forms of adjustments at a higher rate while some are less salient in instruction. More frequently used adjustments are; praise, providing alternatives for perception, activating previous knowledge and highlighting critical features. Less frequent are differentiation of tasks, visible agendas, formative feedback, collaborative peer-learning and self-assessment.

    This essay will furthermore be a basis for collaborative learning among the staff since a deeper knowledge of how instruction can be adjusted and differentiated will impact the outcome of student learning.

     

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  • 5.
    Aadalen, Sandra
    Karlstad University, Faculty of Arts and Social Sciences (starting 2013), Department of Educational Studies (from 2013).
    Arbetslagsledarens uppdrag - distribuerat ledarskap i gymnasieskolan2019Independent thesis Advanced level (degree of Master (Two Years)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This study explores the formation of the teacher team leaders´ role, using interviews and job descriptions at comprehensive upper secondary schools in a Swedish metropolitan municipality. The theoretical framework includes a social constructionist and critical perspective, through Foucault, based on analysis of power. Analysis of power illuminates contemporary practices and techniques through a historical lens, using questions that are related to the basis and logics of power.

    The job descriptions proclaim a diverse, extensive and somewhat scattered mission consisting of administrative duties as well as managing development and evaluation of processes. According to the job description, the teacher team leader is responsible for initiating learning processes as well as implementing decisions by principals, each advocating a different theory. Teacher team leaders describe a complex mission where a substantial amount of time is spent on tasks less prevalent or unmentioned in the job description. Acting as a messenger, yet a constant search for information and administrative duties are tasks that teacher team leaders emphasize.

    In conclusion, it appears as if a comprehensive view of the mission at hand is deficient and that actual practice appears relatively different from the job description. The teacher team leaders operate as a link between school leaders, the Student Health Team and teachers where they contribute to continuity and stability in a school where school leaders more frequently are exchanged. A new and complex organization involving several distributed leadership roles requires thorough work in terms of co-ordination. Future studies may address how interplay and collaboration can work in a complex organization, where preconditions are continuously altered.

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  • 6.
    Aakerlund, Leo
    et al.
    Karlstad University, Faculty of Arts and Social Sciences (starting 2013), Karlstad Business School (from 2013).
    Sjöberg, Hanna
    Karlstad University, Faculty of Arts and Social Sciences (starting 2013), Karlstad Business School (from 2013).
    GRI – ett verktyg för företag att fabricera en hållbar verklighet?2023Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In society today, there is a great focus on sustainability and that companies should contribute to sustainable development. One way to do this is through transparency between the company and its stakeholders regarding how they work on these important issues. This is done through sustainability reports that can be designed in different ways, but this study focuses on those that follow the Global Reporting Initiative, which is the dominant framework globally.

     

    Prior research has shown mixed conclusions regarding GRI and its usefulness. In these, both positive and negative aspects of the framework have been highlighted. This study examines what and how high and low ranked businesses based on SBI report to study the usefulness of GRI. In addition, various theories will be used to examine what may be the reasons for the similarities and differences between the groups. This result is also related to prior research that studied sustainability reporting in connection with the selected theories.

     

    The study was conducted as a method where qualitative data was quantified through a quantitative content analysis. The sustainability reports of 32 companies were reviewed based on their GRI-index and data was then statistically tested using Chi-square-tests and a Fisher's exact test. The study shows that there is no significant difference in what the high and low ranked businesses report. This difference applies to the total number of indicators as well as within the different series, economic, environmental and social. Regarding how the companies report, the study shows that the low ranked businesses are more likely to report indicators for which they do not meet the requirements, this result is also statistically significant. The reasons for the similarities and differences that were identified can be discussed in relations to institutional theory, legitimacy theory and stakeholder theory.

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  • 7.
    Aal, Kotaiba Abdul
    et al.
    Karlstad University, Faculty of Arts and Social Sciences (starting 2013), Service Research Center (from 2013).
    Di Pietro, Laura
    Roma Tre University, Rome, Italy.
    Edvardsson, Bo
    Karlstad University, Faculty of Arts and Social Sciences (starting 2013), Service Research Center (from 2013).
    Renzi, Maria Francesca
    Roma Tre University, Rome, Italy.
    Guglielmetti Mugion, Roberta
    Roma Tre University, Rome, Italy.
    Innovation in service ecosystems: An empirical study of the integration of values, brands, service systems and experience rooms2016In: Journal of Service Management, ISSN 1757-5818, E-ISSN 1757-5826, Vol. 27, no 4, p. 619-651Article in journal (Refereed)
    Abstract [en]

    Purpose – The purpose of this paper is to extend the understanding of innovation in service ecosystems by focussing on the role of values resonance in relation to the integration of brands, service systems and experience rooms.

    Design/methodology/approach – An empirical, explorative case study of an innovative service system is carried out using a narrative approach and presented in the form of a saga.

    Findings – Insights gleaned from the empirical study are used for conceptual developments. Analysis of the empirical case study is presented as four lessons linked to values, brands, service systems and experience rooms.

    Originality/value – The paper extends a conceptual framework of innovative resource integration in service ecosystems. The paper also contributes four propositions to inform theory: values resonance is a basis for service innovation, the innovative integration of brands based on values resonance can foster innovation, the integration of resources across service system boundaries grounded in values resonance can enable innovation and the integration of experience rooms into a coherent servicescape based on values resonance can support novel forms of resource integration and value co-creation efforts in service ecosystems.

    Keywords Service-dominant logic, Brands, Service innovation, Resource integration, Service ecosystem, Values resonance

    Paper type Research paper

  • 8. Aalborg, T.
    et al.
    Strandmark, Margaretha
    Karlstad University, Faculty of Social and Life Sciences, Department of Health and Environmental Sciences.
    The baby was the focus of attention: First-time patients' experiences of their marital relationship2001In: Scandinavian Journal of Caring Sciences, ISSN 0283-9318, E-ISSN 1471-6712, Vol. 15, p. 318-325Article in journal (Refereed)
  • 9. Aalborg, T.
    et al.
    Strandmark, Margaretha
    Karlstad University, Faculty of Social and Life Sciences, Department of Health and Environmental Sciences.
    Dahlöf, LG
    First time parents' sexual relationschips2000In: Scandinavian Journal of Sexology 3; 127-139Article in journal (Refereed)
  • 10.
    Aalto, Irma
    Karlstad University, Faculty of Social and Life Sciences.
    Marknadsföring av religiös turism i Sverige2011Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
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  • 11.
    Aarflot, Johan
    Karlstad University, Faculty of Arts and Social Sciences (starting 2013), Karlstad Business School (from 2013).
    Är framtiden agilt för kommuner?: En studie som undersöker hur projekt bedrivs i kommuner och ställer det mot ett agilt arbetssätt.2019Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    More recently, there has been increased pressure on politically controlled organizations, including municipalities, to become more flexible and find new ways of working. With increased projectification and an increased efficiency as an endeavour for this, it has created organizational tensions in municipal projects. Here, the agile working method in projects has emerged and is seen as a potential solution and a new way of working in projects for a municipal activity.

    The purpose of this study has been to investigate how projects are conducted in a municipal activity and with the issues, how does the agile working method relate to projects at a municipal level and how does the project relate to political governance. In order to be able to answer these, semi-structured interviews were conducted with project managers from different municipalities, with a total of six respondents. The collected material has then been coded through a thematic analysis.

    It is stated that projects carried out in the municipal area need to relate to, among other things, political governance, laws and frameworks. Results also illustrate that there are changes during the course of the projects in municipal projects, which is a burden. The result also indicates that an agile way of working could improve with faster handling of changes in projects. The agile way of working would also work in smaller municipalities because the result indicates that the projects conducted in smaller municipalities are not of the same scope, budget and timeframe, which suits the agile working method.

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  • 12.
    Aarflot, Johan
    et al.
    Karlstad University, Faculty of Arts and Social Sciences (starting 2013), Department of Geography, Media and Communication (from 2013).
    Lundell, Max
    Karlstad University, Faculty of Arts and Social Sciences (starting 2013), Department of Geography, Media and Communication (from 2013).
    Självkörande fordon i stadsrummet?: En studie om självkörande fordons påverkan på individ, mobilitet och planering med fokus på Göteborg Stad2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Självkörande bilar betraktas ofta som nästa steg i utvecklingen av bilen och som en del av det autonoma samhället. Bilproducenter världen över menar att vi kan se självkörande fordon så snart som år 2020 och trycker på både forskning och utveckling av självkörande fordon. Beroende på vilken grad av automatisering och hur politiken tillåter självkörande fordon att inträda i samhället, väcker detta frågor som är viktiga att studera. Vem ska äga självkörande fordon? Vilka kommer att köra självkörande fordon? Kommer det att planeras självkörande fordon? Kommer individens rörelsemönster att ändras? I så fall, hur?

     

    I den här studien försöker vi svara på några av dessa frågor genom att undersöka vad bilen inneburit för individens mobilitet i historien och vad självkörande fordon skulle kunna förändra in i framtiden. Vi ställer oss även frågan om självkörande fordon kommer att påverka planeringen av stadsrummet. Studiens teoretiska referensram utgörs av tidigare forskning och teorier som berör mobiliteten, bilismen och planeringen. Metoden är kvalitativ och utgörs av semistrukturerade intervjuer och dokumentstudier. En intervju gjordes med en respondent från Göteborgs Stad och två stycken intervjuer gjordes Trafikverket. Dokumentstudien utgår ifrån VTI, Statens Väg- och Transportforskningsinstitut och SKL, Sveriges Kommuner och Landsting. Alla de olika myndigheterna har en betydelsefull roll i implementeringen av självkörande fordon och intervjuguiden utgår ifrån de teoretiska utgångspunkterna och den tidigare forskningen.    

     

    I studiens slutsats kommer vi fram till att självkörande fordon påverkar planeringen av stadsrummet, men inte i den stora mån vi först trodde. Planeringen av självkörande fordon kan troligtvis främst ske utanför redan etablerade områden och främst när det planeras nytt. Vi kom även fram till att självkörande fordon kan komma att ändra mobiliteteten hos den urbana individen eftersom självkörande fordon har potentialen att erbjuda fler val av rörelse av rörelse och därmed öka tillgängligheten i stadsrummet.

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  • 13.
    Aarni, Josephine
    et al.
    Karlstad University.
    Hornström, Linda
    Karlstad University.
    Distriktssköterskans ledarskap i hemsjukvård - ett förtroendefullt samarbete: En litteraturstudie2024Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Introduction: Within the next few years more people will need home health care in Sweden, and it will become increasingly advanced. This places high demands on district nurses and nursing staff. The district nurse who is responsible for the patient´s healthcare at home delegates more than half of the healthcare tasks to nursing staff. For this to work, not least for the safety of the patient, the district nurse needs to have an effective leadership. Purpose: To describe district nurse´s experiences of leading nursing staff in home health care. Method: The literature review was carried out in a systematic way with the support of Polit and Beck´s key step and had an inductive design. A total of twelve articles were found which were searched in the databases CINAHL, PsycInfo and PubMed. The data was analyzed through a thematic analysis according to Braun and Clark´s description. Results:  The main theme Person-related factors was built up by the following subthemes: Trusting relationship, Cooperation, Communication and Stress and anxiety. The main theme Organization-related factors was built up by the following subthemes: Allocating nursing tasks, Education and competence and Work environment. Conclusion: Feeling trust and having a trusting relationship with the nursing staff, as well as a functioning collaboration, facilitated leadership for the district nurse. There is a need for trained nursing staff and more time need to be set aside for the district nurse for meetings with the nursing staff, this would facilitate the leadership.

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  • 14.
    Aarnseth, Erika
    Karlstad University, Faculty of Social and Life Sciences.
    Possible correlation between sustainability, wellbeing and traditional African values: Wellbeing factors among citizens in Eastern Cape Province, South Africa2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

     Present development path is based on the Western ideas, with focus on market, competition, capitalism and individualism. It has shown to create unsustainable patterns in terms of a growing ecological footprint, decreased wellbeing and growing inequities. This calls for new, alternative development paths. The traditional African values are based on a holistic and humanistic ideology which focuses on health and safety of common citizens; meeting all peoples basic needs, sharing, social connectedness, living in harmony with other species and nature, a healthy environment, to experience satisfaction when your basic needs are met, not wanting more than you need (luxurious cravings), and the concern for health of future generations. In this sense, traditional values are sustainability bearing, and are also suggested to influence human wellbeing in a positive way.   This study have explored to what extent sustainability-bearing values from the traditional African lifestyle are considered to be important for the wellbeing of young, black individuals, and analyzed whether the values of means to achieve wellbeing differs or corresponds between people living a traditionally influenced lifestyle and a Western influenced lifestyle. Generally, the respondents found all these values more important for their wellbeing than luxurious consumption.     This suggests that values that are sustainability bearing are important for peoples wellbeing, and is thereby important to include in the development debate. 

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  • 15. Aartsen, Marja
    et al.
    Béland, Daniel
    Edmondson, Ricca
    Ginn, Jay
    Komp, Kathrin
    Nilsson, Magnus
    Karlstad University, Faculty of Social and Life Sciences, Department of Social Studies.
    Perek-Bialas, Jolanta
    Sorensen, Penny
    Weicht, Bernard
    Ageing in the light of crises: Economic crisis, demographic change, and the search for meaning2012Report (Other academic)
  • 16.
    Aartsen, Marja
    et al.
    Oslo Metropolitan University, Norway.
    Vangen, Hanna
    Oslo Metropolitan University, Norway.
    Pavlidis, George
    Karlstad University, Faculty of Arts and Social Sciences (starting 2013), Department of Social and Psychological Studies (from 2013).
    Hansen, Thomas
    Norwegian Institute of Public Health, Norway.
    Precupetu, Iuliana
    Research Institute for Quality of Life, Romania; Research Institute of the University of Bucharest, Romania.
    The unique and synergistic effects of social isolation and loneliness on 20-years mortality risks in older men and women2024In: Frontiers in Public Health, E-ISSN 2296-2565, Vol. 12, article id 1432701Article in journal (Refereed)
    Abstract [en]

    Introduction: This study investigates the individual and combined impacts ofloneliness and social isolation on 20-year mortality risks among older men andwomen.Methods: Utilizing data from the Norwegian Life Course, Ageing, and Generationstudy (NorLAG) carried out in 2002, 2007 and 2017, we assessed loneliness viadirect and indirect questions, and social isolation through factors like partnershipstatus and contact frequency with family and friends. Yearly information onmortality was derived from the national registries and was available untilNovember 2022. Gender-stratified Cox regression models adjusted for age andother risk factors were employed.Results: Of the 11,028 unique respondents, 9,952 participants were includedin the study sample, 1,008 (19.8%) women and 1,295 (26.6%) men died. In thefully adjusted models including indirectly assessed loneliness, social isolationincreased the 20-year mortality risk by 16% (HR  =  1.16, 95% CI 1.09–1.24)for women and 15% (HR  =  1.15, 95% CI 1.09–1.21) for men. This effect wasprimarily driven by the absence of a partner and little contact with children forboth genders. Loneliness measured with indirect questions lost its significantassociation with mortality after adjusting for social isolation and other factorsin both genders. However, for men, reporting loneliness via a direct questionwas associated with a higher mortality risk, even in the fully controlled models(HR  =  1.20, 96% CI 1.06–1.36). Interactions between loneliness and socialisolation were not, or only borderline significantly, associated with mortalityrisks in the fully controlled models.Discussion: Social isolation, but not loneliness measured with indirect questionsare associated with a 15–16% higher mortality risk in both men and women.However, loneliness assessed with a direct question is associated with increasedmortality in men, even after controlling for social isolation and other relevantfactors, which might suggest that men may deny loneliness, unless it is (very)severe. These findings emphasize the importance of methodological precisionin the measurement of loneliness and social isolation.

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  • 17.
    Aarås, Andrea
    Karlstad University, Faculty of Arts and Social Sciences (starting 2013), Department of Social and Psychological Studies (from 2013).
    Genusnormers påverkan på den visuella framställningen av kvinnliga fitnesskroppar: En visuell innehållsanalys om genusnormers påverkan på och publikens delaktighet i kvinnliga fitness influencers visuella framställningar av kvinnokroppar2024Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
  • 18.
    Aas, Marit
    et al.
    Oslo universitet.
    Blom, Thomas
    Karlstad University, Faculty of Arts and Social Sciences (starting 2013), Department of Educational Studies (from 2013).
    Benchlearning as professional development of school leaders in Norway and Sweden2018In: Professional Development in Education, ISSN 1941-5257, E-ISSN 1941-5265, Vol. 44, no 1, p. 62-75Article in journal (Refereed)
    Abstract [en]

    In this paper, we investigate a new national collaborative Benchlearning program for principals in Norway and Sweden. Four process leaders have been running the program. The aim is to give the participants the knowledge to develop a leadership practice and school environment that are more innovative. The program includes theoretical inputs, sharing experiences, school visits, training, and trialing of new leadership practices. Drawing on data from surveys, participants’ reflections, and the leaders’ descriptions of new leadership practice, we examine and identify successful and critical aspects of the learning process. The findings show that principals’ motivation and willingness to start change processes can be created in a synergy between structured school visits, work in learning groups, and a theoretical foundation. Working in groups across schools in two countries seems to enhance principals’ sense of efficacy, which in turn is shown to have a positive effect on their willingness to trial new practices. Two implications of the study are suggested. First, in the design of principal programs, systematic and critical reflection about authentic practice should be the basis. Second, educators should be trained to be process leaders who can support principals’ learning during a critical and social construction of a new practice.

  • 19.
    Aas, T. H.
    et al.
    University of Agder, NOR ; NORCE Norwegian Research Centre, NOR.
    Hjemdahl, K. M.
    Norwegian Research Centre, NOR.
    Nordgård, D.
    University of Agder, NOR ; NORCE Norwegian Research Centre, NOR.
    Wästlund, Erik
    Karlstad University, Faculty of Arts and Social Sciences (starting 2013), Department of Social and Psychological Studies (from 2013).
    Outbound open innovation in tourism: Lessons from an innovation project in Norway2021In: Managing Open Service Innovation / [ed] A-L Mention ; Tor Helge Aas, World Scientific, 2021, p. 167-185Chapter in book (Other academic)
    Abstract [en]

    The concept of open innovation was introduced by Henry Chesbrough in 2003 and refers to firms' use of inflows and outflows of knowledge to improve innovation processes. The concept has received considerable scholarly attention, but most research has focused on how manufacturing firms can manage inflows of knowledge during their product innovation processes. How outflows of knowledge can be managed by service firms during their innovation processes has until now not received the same scholarly attention. In this chapter, we therefore aim to contribute in filling this knowledge gap by observing an innovation project in tourism during its implementation. The findings suggested that tourism firms reveal different types of knowledge to other tourism firms in non-pecuniary outbound open innovation processes. In this case the knowledge was revealed in joint workshops where several firms participated and in bi-lateral meetings between two firms, and sometimes the knowledge was transferred via consultants or researchers that acted as "knowledge mediators". The findings also suggested that tourism firms decided to reveal knowledge to other firms to improve their image, increase the market size and to sharpen up their own business. Implications for management as well as the need for further research are discussed in the chapter.

  • 20.
    Aas, Tor Helge
    et al.
    University of Agder, Norway.
    Hjemdahl, Kirsti
    University of Agder, Norway.
    Högberg, Johan
    Karlstad University, Faculty of Arts and Social Sciences (starting 2013), Service Research Center (from 2013).
    Nordgård, Daniel
    University of Agder, Norway.
    Olsson Ramberg, Marcus
    Karlstad University, Faculty of Arts and Social Sciences (starting 2013), Service Research Center (from 2013).
    Wästlund, Erik
    Karlstad University, Faculty of Arts and Social Sciences (starting 2013), Service Research Center (from 2013).
    Contextualizing mobile advertisement using location based services: A field experiment2019Conference paper (Other academic)
  • 21.
    Aasberg, Pål
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Energilager i en överdimensioneradvindkraftspark: En linjäroptimering av batterilager i kombination medintermittenta förnybara energikällor2022Independent thesis Basic level (degree of Bachelor), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    A linear optimization has been made to examine the economic viabilityof incorporating battery storage in a wind farm in Sweden. The studyexamines a future wind farm with 10 10 MW turbines. An orographicmapping with height differences and vegetation has been used incombination with measured wind data with IEC-rated anemometersand wind direction sensors between 1997 and 2017 to create asimulated production in the windPRO software. This effect, togetherwith hourly prices from 2021 from Nord pool in SE1, SE2, SE3, SE4and in Estonia, has been used in a linear optimization in Matlab to findthe battery capacity that generates the most revenue. 3 Scenarios areinvestigated where scenario 1 is a wind farm without battery storagewhere all electricity produced is sold directly at the current price.Scenario 2 also lacks battery storage and has a power limit of 75 MWat the transformer whilst the farm still produces 100 MW. Scenario 3has a power limit of 75 MW at the transformer and the possibility ofbattery storage.

  • 22.
    Aasen, Andreas
    Karlstad University, Faculty of Arts and Social Sciences (starting 2013), Department of Artistic Studies.
    Vi har sett och hört den, men var då?: En enkätundersökning om barns och vuxnas relation till instrumentet trumpet2014Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The study's purpose is to investigate whether children and parents know the instrument trumpet and the beliefs they have about this instrument.  

     

    My questions are:

     

    • What do 6 and 7-year-olds and their parents know of the instrument trumpet? 
    • What are their beliefs concerning the trumpet and what does the trumpet mean to them? 

     

    To find out about these questions, I have conducted a survey study in Arvika with children in first grade and their parents. 33 adults and 34 children from three schools took part in the survey.

     

    The results showed that knowledge of the trumpet are quite good among 6 and 7-year-olds and their parents. All the respondents in this survey know what the trumpet is, and over one-third of the 67 respondents know about someone who plays the trumpet. Among the children exist no big "celebrity" trumpet player. Instead they mention friends or acquaintances that play the instrument. There were some well-known musicians among adults but it was often aging jazz trumpeters. 6 and 7-year-olds are pretty open-minded about trumpet. They seem to consider both that young, old, men and women could be playing the trumpet. The parents, however, think that men dominate playing the trumpet. Otherwise are the parents also pretty open-minded. The music school appears to have a strong name in Arvika. Many respondents stated that it´s possible to contact the music school if you want to start playing the trumpet. The results also showed that the trumpet is not considered as boring. Most people put it midway between boring and fun to play.

     

    Based on the findings in this study, the trumpet seems to be a well-known and somewhat appreciated instrument among the respondents. At the same time it seems to be a bit out of range from a satisfying reputation.

     

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  • 23.
    Abadzhiev, Andrey
    Karlstad University, Faculty of Arts and Social Sciences (starting 2013), Karlstad Business School (from 2013). Karlstad University, Faculty of Arts and Social Sciences (starting 2013), Service Research Center (from 2013).
    Advancing circular thinking: strategies and practicesManuscript (preprint) (Other academic)
    Abstract [en]

    Research on circular economy (CE) provides insight into the different components of circularity transitions, but often falls short of offering a more holistic view of strategy implementation and managerial guidance. The aim of this study is twofold: first, to understand how firms implement specific CE strategies in practice and second, to identify specific dynamic capabilities related to these strategies. Our research was conducted on the Swedish wood construction industry, which draws attention with its circular technologies and practices. Our data consisted of open- and closed-ended questions from 35 senior managers and CEOs in the construction value chain regarding the relevance of implementing different CE principles to their perception of high circularity. The data were analyzed using fuzzy set qualitative comparative analysis (fsQCA) to uncover strategies (i.e. combinations of CE principles) for high circularity. Our findings reveal and explain four strategies towards circularity: a) The value chain steward, b) The circular product developer, c) The waste watcher, and d) The holistic resource organizer. The findings also identify specific organizational capabilities that enable innovation activities critical for the CE transition. Such innovations go beyond the mere integration of circular technologies, highlighting the importance of using sufficiency-based principles to develop circular business models. 

  • 24.
    Abadzhiev, Andrey
    Karlstad University, Faculty of Arts and Social Sciences (starting 2013), Karlstad Business School (from 2013). Karlstad University, Faculty of Arts and Social Sciences (starting 2013), Service Research Center (from 2013).
    Managing business model innovation for sustainability transitions: Towards a theory-based typology2024Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Business model innovation for sustainability (BMIfS) is a key driver for industry transformations in addressing grand challenges. While previous corporate sustainability literature has acknowledged that companies require different management approaches to innovate their business model for larger system changes, a more structured and nuanced understanding of such management has not often been applied. By developing a theory-based typology, this thesis explores how management and social theories can be used to advance BMIfS research. The typology accumulates and organizes existing knowledge of the important but fragmented BMIfS management research to capture the key dimensions and differentiate among various management approaches. From a management perspective, the thesis identifies three BMIfS management dimensions: values, knowledge, and agency. The thesis consists of four appended empirical papers that illustrate various facets of the BMIfS management typology. The empirical data from those papers is based on case studies of the Swedish wood construction industry, which has attracted international attention due to the development of innovative and sustainable building technologies and practices. This thesis makes three main contributions. First, it contributes to a growing discussion in the management researcher and practitioner communities on advancing the managerial perspectives of BMIfS. Second, it presents a theory-based typology of different BMIfS management approaches and their theoretical roots. Third, it illustrates various facets of these management approaches with empirical examples from the four appended papers.

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  • 25.
    Abadzhiev, Andrey
    Karlstad University, Faculty of Arts and Social Sciences (starting 2013), Karlstad Business School (from 2013). Karlstad University, Faculty of Arts and Social Sciences (starting 2013), Service Research Center (from 2013).
    [Manuscript] Advancing circular thinking: strategies and practicesManuscript (preprint) (Other academic)
  • 26.
    Abadzhiev, Andrey
    Karlstad University, Faculty of Arts and Social Sciences (starting 2013), Karlstad Business School (from 2013). Karlstad University, Faculty of Arts and Social Sciences (starting 2013), Service Research Center (from 2013).
    [Manuscript] Re-orientation of incumbents towards a circular economy: a perspective on creative accumulationManuscript (preprint) (Other academic)
  • 27.
    Abadzhiev, Andrey
    Karlstad University, Faculty of Arts and Social Sciences (starting 2013), Karlstad Business School (from 2013). Karlstad University, Faculty of Arts and Social Sciences (starting 2013), Service Research Center (from 2013).
    Re-orientation of incumbents towards a circular economy: a perspective on creative accumulationManuscript (preprint) (Other academic)
    Abstract [en]

    The growing challenges of climate change and resource depletion have exposed the limitations of the traditional 'take-make-dispose' production and consumption model. In response, the concept of the circular economy (CE) has gained prominence as an alternative approach that emphasizes reducing, reusing, recycling, and recovering materials. However, transitioning to a CE requires profound socio-technical changes, often disrupting linear business models and posing significant threats to established incumbent organizations. Incumbents, face difficulties in adapting to CE transitions due to misalignments between their existing competencies and the new demands of circularity. This paper examines the strategic challenges that incumbents encounter during these transitions, focusing on the tension between exploiting existing competencies and exploring new technological and business opportunities. Through a multiple-case study in the Swedish wood construction industry, the paper highlights the dual challenge of improving current practices while venturing into unknown territory. The empirical data is drawn from the Swedish wood construction industry, which has gained international attention for its development of innovative and sustainable building technologies and practices. The findings show how incumbents are responding to sustainability transitions through the process of creative accumulation, which integrate both new and existing knowledge to develop circular value propositions. The study argues that established players can be well-positioned to collaborate and capitalize on circular transitions if they adjust their business models to aligning around sustainable principles and balance between innovation and accumulated expertise. 

  • 28.
    Abadzhiev, Andrey
    Karlstad University, Faculty of Arts and Social Sciences (starting 2013), Karlstad Business School (from 2013).
    Scaling sustainable technology in a traditional industryManuscript (preprint) (Other academic)
  • 29.
    Abadzhiev, Andrey
    Karlstad University, Faculty of Arts and Social Sciences (starting 2013), Karlstad Business School (from 2013).
    Wood We Change?: Business Model Innovation Towards Sustainability Transitions: Studying the Wood Construction Industry2021Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Innovations based on sustainable technologies have been widely considered as a remedy for addressing societal and environmental problems in many industries. However, the large-scale adoption of such innovations goes beyond technology and requires organizing the business in a way that drive industrial transformations across actors and system layers, such as market structures, institutional frames, consumer behavior, and business values. 

    The aim of this dissertation is to understand how industrial firms organize for system change towards sustainability. The study is a compilation of two papers within the same research context: the development of sustainable technology in the construction industry. The overlapping unit of analysis for both papers is business model innovation. Paper I examines how industry firms combine and complement business models with different innovation types to accelerate sustainable technology. Paper II identifies how a change in the business model and value creation logic that occur on a firm level accelerate sustainable technology and shape the socio-technical system. Together, both papers help paint a more complete picture of the business model role in transitions towards sustainability. The theoretical frame of this dissertation spans several domains: business model, innovation management, and sustainability transitions. Building on a multi-disciplinary premise, the study takes into account the organizational and the systemic parts of the change process by linking the company perspective (business models) to the wider governance of sustainability transitions. 

    The findings underline the importance of business models that combine production efficiency with higher customer engagement and more collective value creation for driving larger-scale transitions toward sustainability. Moreover, business models in combination with different innovation types, such as product, process and positioning, act together and complement each other to achieve high sustainability and business outcomes. 

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  • 30.
    Abadzhiev, Andrey
    et al.
    Karlstad University, Faculty of Arts and Social Sciences (starting 2013), Karlstad Business School (from 2013). Karlstad University, Faculty of Arts and Social Sciences (starting 2013), Service Research Center (from 2013).
    Sukhov, Alexandre
    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), Karlstad Business School (from 2013).
    Johnson, Mikael
    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), Karlstad Business School (from 2013).
    Business model innovation for reducing uncertainty in sustainability transitions: A case study of the wood construction industry2024In: Creativity and Innovation Management, ISSN 0963-1690, E-ISSN 1467-8691Article in journal (Refereed)
    Abstract [en]

    Sustainability transitions are a significant challenge that requires established industries to adopt innovative ways of doing business. Research suggests that while this is possible through business model innovation (BMI), risk avoidance by regime actors and high levels of future uncertainty act as barriers to successful transitions. Specifically, we lack knowledge about how established companies innovate their business model (BM) to reduce uncertainty related to sustainability transitions. We explore the case of a large forest-based manufacturing company in the construction industry, Stora Enso. We find that, by pursuing transformative BMI and combining multiple value creation logics, a company can reduce different types of uncertainty while shaping its business ecosystem towards more sustainable opportunities. We show that the BM can serve as an organizational tool for collectively exploring new knowledge, reducing uncertainty and driving change in a business ecosystem.

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  • 31.
    Abadzhiev, Andrey
    et al.
    Karlstad University, Faculty of Arts and Social Sciences (starting 2013), Service Research Center (from 2013).
    Sukhov, Alexandre
    Karlstad University, Faculty of Arts and Social Sciences (starting 2013), Service Research Center (from 2013).
    Sihvonen, Antti
    Jyväskylä University, FIN.
    Johnson, Mikael
    Karlstad University, Faculty of Arts and Social Sciences (starting 2013), Service Research Center (from 2013).
    Managing the complexity of green innovation2022In: European Journal of Innovation Management, ISSN 1460-1060, E-ISSN 1758-7115, Vol. 25, no 6, p. 850-866Article in journal (Refereed)
    Abstract [en]

    Purpose Green innovation can promote both environmental sustainability and economic growth. However, its development and implementation can be complex due to the need to align innovation activities within and across companies. In this study, the authors examined how this complexity can be managed by analyzing how individual companies combine different innovation activities to develop green innovation, and how companies along the value chain align to implement these innovations. Design/methodology/approach The dataset comprises both interviews and a survey of senior executives from the Swedish wood construction industry. These data were first analyzed by using fuzzy set qualitative comparative analysis (fsQCA) to identify innovation activity configurations at the level of the individual company. The interviews were then analyzed to identify alignment mechanisms enabling the implementation of green innovation along the value chain. Findings At the company level, the authors found three innovation activity configurations with varying levels of complexity: (1) systemic innovation by proactive companies, (2) process innovation by reactive companies and (3) inaction by technology-independent companies. On the value chain level, the authors found three alignment mechanisms that facilitate the implementation of green innovation along the value chain. These mechanisms promote cooperation by increasing efficiency, opening up new market opportunities and increasing the level of servitization. Originality/value This paper analyzes the complexity of green innovation and provides novel insights into how complexity is managed at the level of both the individual company and the value chain.

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  • 32.
    Abas, Naeem
    et al.
    University of Gujrat, Hafiz Hayat Campus, Pakistan.
    Kalair, Ali Raza
    COMSATS University Islamabad, Pakistan.
    Seyedmahmoudian, Mehdi
    Swinburne University, Australia.
    Naqvi, Muhammad
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Campana, Pietro Elia
    Mälardalen University, Sweden.
    Khan, Nasrullah
    COMSATS University Islamabad, Pakistan.
    Dynamic simulation of solar water heating system using supercritical CO2 as mediating fluid under sub-zero temperature conditions2019In: Applied Thermal Engineering, ISSN 1359-4311, E-ISSN 1873-5606, Vol. 161, article id 114152Article in journal (Refereed)
    Abstract [en]

    CO2 is becoming increasingly important as a mediating fluid, and simulation studies are indispensable for corresponding developments. In this study, a simulation-based performance investigation of a solar water heating system using CO2 as a mediating fluid under sub-zero temperature condition is performed using the TRNSYS (R) software. The maximum performance is achieved at a solar savings fraction of 0.83 during July. The as lowest solar savingss fraction of 0.41 is obtained during December. The annual heat production of the proposed system under Fargo climate is estimated to be about 2545 kWh. An evacuated glass tube solar collector is designed, fabricated and tested for various climate conditions. Moreover, a detailed comparison of the system's performance at sub/supercritical and supercritical pressures shows that the annual heat transfer efficiency of the modeled system is 10% higher at supercritical pressure than at sub/supercritical pressures. This result can be attributd to the strong convection flow of CO2 caused by density inhomogeneities, especially in the near critical region. This condition resuls in high heat transfer rates.

  • 33.
    Abascal, Angela
    et al.
    University of Navarra, Spain; University of Twente, Netherlands.
    Georganos, Stefanos
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Environmental and Life Sciences (from 2013).
    Kuffer, Monika
    University of Twente, Netherlands.
    Vanhuysse, Sabine
    Université libre de Bruxelles (ULB), Belgium.
    Thomson, Dana
    University of Twente, Netherlands.
    Wang, Jon
    University of Twente, Netherlands.
    Manyasi, Lawrence
    Community Researcher Non-affiliated, Nairobi, Kenya.
    Otunga, Daniel Manyasi
    Community Researcher Single Mother Association of Kenya, Nairobi, Kenya.
    Ochieng, Brighton
    Community Researcher Non-affiliated, Nairobi, Kenya.
    Ochieng, Treva
    Community Researcher Non-affiliated, Nairobi, Kenya.
    Klinnert, Jorge
    University of Maryland, USA.
    Wolff, Eléonore
    Université libre de Bruxelles (ULB), Belgium.
    Making Urban Slum Population Visible: Citizens and Satellites to Reinforce Slum Censuses2024In: Urban Inequalities from Space: Earth Observation Applications in the Majority World / [ed] Monika Kuffer, Stefanos Georganos, Springer, 2024, Vol. 26, p. 287-302Chapter in book (Refereed)
    Abstract [en]

    In response to the “Leave No One Behind” principle (the central promise of the 2030 Agenda for Sustainable Development), reliable estimate of the total number of citizens living in slums is urgently needed but not available for some of the most vulnerable communities. Not having a reliable estimate of the number of poor urban dwellers limits evidence-based decision-making for proper resource allocation in the fight against urban inequalities. From a geographical perspective, urban population distribution maps in many low- and middle-income cities are most often derived from outdated or unreliable census data disaggregated by coarse administrative units. Moreover, slum populations are presented as aggregated within bigger administrative areas, leading to a large diffuse in the estimates. Existing global and open population databases provide homogeneously disaggregated information (i.e. in a spatial grid), but they mostly rely on census data to generate their estimates, so they do not provide additional information on the slum population. While a few studies have focused on bottom-up geospatial models for slum population mapping using survey data, geospatial covariates, and earth observation imagery, there is still a significant gap in methodological approaches for producing precise estimates within slums. To address this issue, we designed a pilot experiment to explore new avenues. We conducted this study in the slums of Nairobi, where we collected in situ data together with slum dwellers using a novel data collection protocol. Our results show that the combination of satellite imagery with in situ data collected by citizen science paves the way for generalisable, gridded estimates of slum populations. Furthermore, we find that the urban physiognomy of slums and population distribution patterns are related, which allows for highlighting the diversity of such patterns using earth observation within and between slums of the same city. 

  • 34.
    Abascal, Angela
    et al.
    University of Navarra, Spain.
    Vanhuysse, Sabine
    Université libre de Bruxelles, Belgium.
    Grippa, Taïs
    Université libre de Bruxelles, Belgium.
    Rodriguez-Carreño, Ignacio
    University of Navarra, Spain.
    Georganos, Stefanos
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Environmental and Life Sciences (from 2013).
    Wang, Jiong
    University of Twente, Netherlands.
    Kuffer, Monika
    University of Twente, Netherlands.
    Martinez-Diez, Pablo
    300.000 Km/s, Barcelona, Spain.
    Santamaria-Varas, Mar
    300.000 Km/s, Barcelona, Spain.
    Wolff, Eleonore
    Université libre de Bruxelles, Belgium.
    AI perceives like a local: predicting citizen deprivation perception using satellite imagery2024In: npj Urban Sustainability, E-ISSN 2661-8001, Vol. 4, no 1, article id 20Article in journal (Refereed)
    Abstract [en]

    Deprived urban areas, commonly referred to as ‘slums,’ are the consequence of unprecedented urbanisation. Previous studies have highlighted the potential of Artificial Intelligence (AI) and Earth Observation (EO) in capturing physical aspects of urban deprivation. However, little research has explored AI’s ability to predict how locals perceive deprivation. This research aims to develop a method to predict citizens’ perception of deprivation using satellite imagery, citizen science, and AI. A deprivation perception score was computed from slum-citizens’ votes. Then, AI was used to model this score, and results indicate that it can effectively predict perception, with deep learning outperforming conventional machine learning. By leveraging AI and EO, policymakers can comprehend the underlying patterns of urban deprivation, enabling targeted interventions based on citizens’ needs. As over a quarter of the global urban population resides in slums, this tool can help prioritise citizens’ requirements, providing evidence for implementing urban upgrading policies aligned with SDG-11.

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  • 35.
    Abascal, Angela
    et al.
    Public University of Navarre, Spain.
    Wang, Jon
    University of Twente, Netherlands.
    Kuffer, Monika
    University of Twente, Netherlands.
    Georganos, Stefanos
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Environmental and Life Sciences (from 2013).
    Vanhuysse, Sabine
    Université Libre de Bruxelles (ULB), Belgium.
    Heat Exposure of Deprivation Through Air Temperature Modelling2024In: Proceedings-International Geoscience and Remote Sensing Symposium (IGARSS), Institute of Electrical and Electronics Engineers (IEEE), 2024, p. 1156-1159Conference paper (Refereed)
    Abstract [en]

    Many studies are pointing to the fact that cities are experiencing higher temperatures than non-built-up areas. Yet limited can be found on thermal inequalities in the context of vulnerable groups, specifically linked to people living in deprivation. Here, we study heat patterns across vulnerable groups living in deprivation as an important effort that should be paralleled to the other urban climate studies and aim at answering two primary questions: (1) how temperature varies within and across deprived areas, and (2) what the key driving factors are for such variation. We conduct intensive in-situ measurements by involving local residents in air temperature traverse across deprived neighbourhoods and modelling the pattern of air temperature with spatial covariates. We also compare different modelling techniques while securing the interpretability of the air temperature pattern by using understandable spatial covariates, which is especially informative for mitigation and adaptation, and linking scientific exploration and practical solutions. 

  • 36.
    Abbas, Asad
    Karlstad University, Faculty of Technology and Science.
    Flow sheeting software as a tool when teaching Chemical Engineering2011Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The aim of this thesis is to design different chemical processes by using flow sheeting software and to show the usefulness of flow sheeting software as an educational tool. The industries studied are hydrogen, sulfur, nitric acid and ethylene glycol production and a model of drying technique is also included. Firstly, there is an introduction of chemcad as a tool when teaching chemical processes and explanation of each industry which is selected to design. Various production methods for each product are explained and the advantages of the method which is selected to design the chemical flow sheet are discussed. There is also an introduction of the industrial uses of these products formed in Pakistan. The models are designed by using different reactors, heat exchangers, pumps, mixers, boilers and distillation column. The models are designed based upon data taken from literature. The temperature and pressure values are in good agreement with data mentioned in literature. The material balance shown by Chemcad is quite different from data mentioned in literature. Some changes in thermodynamic properties of components in Chemcad software might lead to better agreement between the Chemcad models and literature data. It is not possible to use catalyst in Chemcad to increase the rate of reaction. One possibility is to introduce new components. It is good to use equilibrium reactor when it is required to convert the given component into respective products provided that either conversion of the equilibrium constant are known. It is difficult to study the hidden critical assumptions built in the model when using Gibb’s reactor, as a result there is a deviation in behavior from the system described in the literature. Gibb’s reactor is useful when neither conversion ratio nor equilibrium constant is known.

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  • 37.
    Abbas, Azhar
    Karlstad University, Faculty of Technology and Science.
    GPIB- kommunikation och PID reglering med LabVIEW2009Independent thesis Basic level (university diploma), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [sv]

    LabVIEW ger en snabb och enkel tillgång till att styra instrument och en mycket stor databas med drivrutiner för DAQ-kort och olika datorgränssnitt (GPIB, serie, osv.).

    Många instrument och datorer kan anslutas till GPIB-bussen.  Detta kan ge en praktisk modell för utveckling av instrumentets styrprogram i LabVIEW med hjälp av GPIB-gränssnittet.

    Ett program i LabVIEW 8.2 med hjälp av GPIB-bussen kan kopplas till t.ex. multimetern (HP-34401A) för att mäta och visa multimeters noggrannhet. Men på grund av fel i drivrutiner för GPIB-gränssnittet kunde jag inte köra programmet med GPIB-bussen.

    Genom att använda LabVIEW 8.2 med hjälp av DAQ-kort kan en PID-regleringsalgoritm simuleras. PID konstrueras med virtuella instrument som innehåller alla nödvändiga komponenter och utrustning som krävs för att reglera någon linjär eller olinjär process exempelvis att nivåreglera två tankar i serie. Här stöter vi på alla de grundläggande regulatorer och får möjlighet att bygga PID med LabVIEW på ett enkelt sätt. Det finns två metoder för att bygga PID. Den första är med matematiska funktioner och den andra är med ’’Simulations functions control’’. Arbetet visar att bägge metoderna fungerar bra för att lösa uppgiften jämfört med färdiga PID-controls på LabVIEW.

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  • 38.
    Abbas, Husam
    Karlstad University.
    Comparative analysis of different pyrolysis techniques by using kraft lignin: Jämförelse mellan olika pyrolys metoder2020Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This thesis presents a comparison analysis between various pyrolysis techniques performed on kraft lignin. Numerous literature studies of pyrolysis techniques performed on kraft lignin are reviewed and analysed where different operation temperatures, catalysts and different heating methods are used to pyrolyze kraft lignin. Based on the collected data from the reviewed literature, calculations are performed to determine energy efficiency of each pyrolysis technique. The energy efficiencies are used to establish a comparison between various pyrolysis techniques. Energy efficiencies of all pyrolysis techniques are determined by using series of equations.

    Dissimilarities of products composition are investigated between various pyrolysis techniques. Environmental impacts caused by lignin pyrolysis are reviewed and discussed. Uses of products produced from lignin pyrolysis are discussed to highlight the potential of using lignin as an energy resource to produce biooil, biochar and non-condensable gases (NCG).

    Results show that energy efficiencies differ significantly between various pyrolysis techniques, where microwave-assisted pyrolysis (MAP) shows the highest energy efficiency. Products produced from pyrolysis show a wide range of uses in many industrial applications. Lignin based products have the potential to replace many petroleum-based products which may contribute significantly to decrease pollutants in nature and gas emissions caused by combusting fossil fuels.

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  • 39.
    Abbas, Mhd Yazan
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013). Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science.
    Ferzali, Ali
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013). Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science.
    A mobile Application development in the Android Studio platform for leave applications2022Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Nowadays, there is a mobile application for almost every need, for instance, training, games, and news applications. Almost all the companies have also their own mobile applications that facilitate the daily communication between their employees and supervisors. In this thesis, the development process of an Android application for the company Askås is created, where the employees can for example send a Flex application or sick leave application, see their registered personal information and edit them. The final result of the project is almost what Askås asked for, An Android application that facilitates their employees’ daily needs. The development process, the results, and the encountered problems are also represented in a more detailed manner in the thesis. 

  • 40.
    Abbas, Muhammad Tahir
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Improving the Energy Efficiency of Cellular IoT Device2023Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Cellular Internet of Things (CIoT) has emerged as a promising technology to support applications that generate infrequent data. One requirement on these applications, often battery-powered devices, is low energy consumption to enable extended battery life. Narrowband IoT (NB-IoT) is a promising technology for IoT due to its low power consumption, which is essential for devices that need to run on battery power for extended periods. However, the current battery life of NB-IoT devices is only a few years, which is insufficient for many applications. This thesis investigates the impact of energy-saving mechanisms standardized by 3GPP on battery life of NB-IoT devices. The main research objective is to classify and analyze existing energy-saving solutions for CIoT and examine their limitations, to study the impact of standardized energy-saving mechanisms on the battery life of NB-IoT devices, both in isolation and combined, and to provide guidelines on how to configure NB-IoT devices to reduce energy consumption efficiently. The research aims to provide a deeper understanding of the effect of energy-saving mechanisms and best practices to balance energy efficiency and performance of NB-IoT devices. Applying the proposed solutions makes it possible to achieve a battery life of 10~years or more for CIoT devices.

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  • 41.
    Abbas, Muhammad Tahir
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Eklund, Johan
    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).
    Alfredsson, Stefan
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Rajiullah, Mohammad
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Grinnemo, Karl-Johan
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Caso, Giuseppe
    Ericsson Research.
    Kousias, Konstantinos
    Simula Research Laboratory, Norway.
    Alay, Özgü
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013). University of Oslo, Norway.
    On the Energy-efficient Use of Discontinuous Reception and Release Assistance in NB-IoT2022Conference paper (Refereed)
    Abstract [en]

    Cellular Internet of Things (CIoT) is a Low-Power Wide-Area Network (LPWAN) technology. It aims for cheap, lowcomplexity IoT devices that enable large-scale deployments and wide-area coverage. Moreover, to make large-scale deployments of CIoT devices in remote and hard-to-access locations possible, a long device battery life is one of the main objectives of these devices. To this end, 3GPP has defined several energysaving mechanisms for CIoT technologies, not least for the Narrow-Band Internet of Things (NB-IoT) technology, one of the major CIoT technologies. Examples of mechanisms defined include CONNECTED-mode DRX (cDRX), Release Assistance Indicator (RAI), and Power Saving Mode (PSM). This paper considers the impact of the essential energy-saving mechanisms on minimizing the energy consumption of NB-IoT devices, especially the cDRX and RAI mechanisms. The paper uses a purpose-built NB-IoT simulator that has been tested in terms of its built-in energy-saving mechanisms and validated with realworld NB-IoT measurements. The simulated results show that it is possible to save 70%-90% in energy consumption by enabling the cDRX and RAI. In fact, the results suggest that a battery life of 10 years is only achievable provided the cDRX, RAI, and PSM energy-saving mechanisms are correctly configured and used

  • 42.
    Abbas, Muhammad Tahir
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Eklund, Johan
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Grinnemo, Karl-Johan
    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).
    Impact of Tunable Parameters in NB-IoT Stack onthe Energy Consumption2019In: Proceedings of Fifteenth Swedish National Computer Networking Workshop (SNCNW), 2019Conference paper (Refereed)
    Abstract [en]

    This paper studies the impact of tunable parametersin the NB-IoT stack on the energy consumption of a user equipment(UE), e.g., a wireless sensor. NB-IoT is designed to enablemassive machine-type communications for UE while providing abattery lifetime of up to 10 years. To save battery power, most oftime the UE is in dormant state and unreachable. Still, duringthe CONNECTED and IDLE state, correct tuning of criticalparameters, like Discontinuous reception (DRX), and extendedDiscontinuous reception (eDRX), respectively, are essential to savebattery power. Moreover, the DRX and eDRX actions relate tovarious parameters which are needed to be tuned in order toachieve a required UE battery lifetime. The objective of thispaper is to observe the influence of an appropriate tuning ofthese parameters to reduce the risk of an early battery drainage

  • 43.
    Abbas, Muhammad Tahir
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Eklund, Johan
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Grinnemo, Karl-Johan
    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). Karlstad University, Faculty of Health, Science and Technology (starting 2013), Science, Mathematics and Engineering Education Research.
    Alfredsson, Stefan
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Science, Mathematics and Engineering Education Research. Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Alay, Özgü
    University of Oslo and Simula Metropolitan, NOR.
    Katona, Sándor
    Ericsson AB.
    Seres, Gergely
    Ericsson AB.
    Rathonyi, Bela
    Ericsson AB.
    Guidelines for an Energy Efficient Tuning of the NB-IoT Stack2020In: 45th IEEE Conference on Local Computer Networks (LCN), IEEE Communications Society, 2020, p. 60-69, article id 9363265Conference paper (Refereed)
    Abstract [en]

    In this paper, we study the energy consumptionof Narrowband IoT devices. The paper suggests that key tosaving energy for NB-IoT devices is the usage of full Discontinuous Reception (DRX), including the use of connected-mode DRX (cDRX): In some cases, cDRX reduced the energy consumption over a 10-year period with as much as 50%. However, the paper also suggests that tunable parameters, such as the inactivity timer, do have a significant impact. On the basis of our findings, guidelines are provided on how to tune the NB-IoT device so that it meets the target of the 3GPP, i.e., a 5-Wh battery should last for at least 10 years. It is further evident from our results that the energy consumption is largely dependent on the intensity and burstiness of the traffic, and thus could be significantly reduced if data is sent in bursts with less intensity,irrespective of cDRX support.

  • 44.
    Abbas, Muhammad Tahir
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Grinnemo, Karl-Johan
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Brunstrom, Anna
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Jörke, Pascal
    TU Dortmund University, Germany.
    Eklund, Johan
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Alfredsson, Stefan
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Rajiullah, Mohammad
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Wietfeld, Christian
    TU Dortmund University, Germany.
    Evaluating the Impact of Pre-Configured Uplink Resources in Narrowband IoT2024In: Sensors, E-ISSN 1424-8220, Vol. 24, no 17, article id 5706Article in journal (Refereed)
    Abstract [en]

    Deploying Cellular Internet of Things (CIoT) devices in urban and remote areas faces significant energy efficiency challenges. This is especially true for Narrowband IoT (NB-IoT) devices, which are expected to function on a single charge for up to 10 years while transmitting small amounts of data daily. The 3rd Generation Partnership Project (3GPP) has introduced energy-saving mechanisms in Releases 13 to 16, including Early Data Transmission (EDT) and Preconfigured Uplink Resources (PURs). These mechanisms extend battery life and reduce latency by enabling data transmission without an active Radio Resource Control (RRC) connection or Random Access Procedure (RAP). This paper examines these mechanisms using the LENA-NB simulator in the ns-3 environment, which is a comprehensive framework for studying various aspects of NB-IoT. The LENA-NB has been extended with PURs, and our analysis shows that PURs significantly enhance battery life and latency efficiency, particularly in high-density environments. Compared to the default RAP method, PURs reduce energy consumption by more than 2.5 times and increases battery life by 1.6 times. Additionally, PURs achieve latency reductions of 2.5 - 3.5 times. The improvements with PURs are most notable for packets up to 125 bytes. Our findings highlight PURs' potential to enable more efficient and effective CIoT deployments across various scenarios. This study represents a detailed analysis of latency and energy consumption in a simulated environment, advancing the understanding of PURs' benefits.

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  • 45.
    Abbas, Muhammad Tahir
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Grinnemo, Karl-Johan
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Eklund, Johan
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Alfredsson, Stefan
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Rajiullah, Mohammad
    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).
    Caso, Giuseppe
    Ericsson Research, Sweden.
    Kousias, Konstantinos
    Simula Research Laboratory, Norway.
    Alay, Özgü
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013). University of Oslo, Norway.
    Energy-Saving Solutions for Cellular Internet of Things - A Survey2022In: IEEE Access, E-ISSN 2169-3536, Vol. 10, p. 62096-62096Article in journal (Refereed)
    Abstract [en]

    The Cellular Internet of Things (CIoT), a new paradigm, paves the way for a large-scale deployment of IoT devices. CIoT promises enhanced coverage and massive deployment of low-cost IoT devices with an expected battery life of up to 10 years. However, such a long battery life can only be achieved provided the CIoT device is configured with energy efficiency in mind. This paper conducts a comprehensive survey on energy-saving solutions in 3GPP-based CIoT networks. In comparison to current studies, the contribution of this paper is the classification and an extensive analysis of existing energy-saving solutions for CIoT, e.g., the configuration of particular parameter values and software modifications of transport- or radio-layer protocols, while also stressing key parameters impacting the energy consumption such as the frequency of data reporting, discontinuous reception cycles (DRX), and Radio Resource Control (RRC) timers. In addition, we discuss shortcomings, limitations, and possible opportunities which can be investigated in the future to reduce the energy consumption of CIoT devices.

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  • 46.
    Abbas, Muhammad Tahir
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Grinnemo, Karl-Johan
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Ferré, G.
    University of Bordeaux, Bordeaux, France.
    Laurent, P.
    University of Liège, Liège, Belgium.
    Alfredsson, Stefan
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Rajiullah, Mohammad
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Eklund, Johan
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Towards zero-energy: Navigating the future with 6G in Cellular Internet of Things2024In: Journal of Network and Computer Applications, ISSN 1084-8045, E-ISSN 1095-8592, Vol. 230, article id 103945Article in journal (Refereed)
    Abstract [en]

    The Cellular Internet of Things (CIoT) has seen significant growth in recent years. With the deployment of 5G, it has become essential to reduce the power consumption of these devices for long-term sustainability. The upcoming 6G cellular network introduces the concept of zero-energy CIoT devices, which do not require batteries or manual charging. This paper focuses on these devices, providing insight into their feasibility and practical implementation. The paper examines how CIoT devices use simultaneous wireless information and power transfer, beamforming, and backscatter communication techniques. It also analyzes the potential use of energy harvesting and power management in zero-energy CIoT devices. Furthermore, the paper explores how low-power transceivers can lower energy usage while maintaining dependable communication functions.

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    Download full text (pdf)
    Accepted version
  • 47.
    Abbas, Muhammad Tahir
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Jibran, Muhammad Ali
    Jeju Natl Univ, Dept Comp Engn, Jeju 63243, South Korea..
    Afaq, Muhammad
    Sarhad Univ Sci & Informat Technol, Pakistan..
    Song, Wang-Cheol
    Jeju Natl Univ, South Korea..
    An adaptive approach to vehicle trajectory prediction using multimodel Kalman filter2020In: European transactions on telecommunications, ISSN 1124-318X, E-ISSN 2161-3915, article id e3734Article in journal (Refereed)
    Abstract [en]

    With the aim to improve road safety services in critical situations, vehicle trajectory and future location prediction are important tasks. An infinite set of possible future trajectories can exit depending on the current state of vehicle motion. In this paper, we present a multimodel-based Extended Kalman Filter (EKF), which is able to predict a set of possible scenarios for vehicle future location. Five different EKF models are proposed in which the current state of a vehicle exists, particularly, a vehicle at intersection or on a curve path. EKF with Interacting Multiple Model framework is explored combinedly for mathematical model creation and probability calculation for that model to be selected for prediction. Three different parameters are considered to create a state vector matrix, which includes vehicle position, velocity, and distance of the vehicle from the intersection. Future location of a vehicle is then used by the software-defined networking controller to further enhance the safety and packet delivery services by the process of flow rule installation intelligently to that specific area only. This way of flow rule installation keeps the controller away from irrelevant areas to install rules, hence, reduces the network overhead exponentially. Proposed models are created and tested in MATLAB with real-time global positioning system logs from Jeju, South Korea.

  • 48.
    Abbas, Muhammad Tahir
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Muhammad, Afaq
    Sarhad Univ Sci & Informat Technol, Dept Comp Sci & IT, Peshawar, Pakistan.
    Song, Wang-Cheol
    Jeju Natl Univ, Dept Comp Engn, Jeju, South Korea.
    Road-Aware Estimation Model for Path Duration in Internet of Vehicles (IoV)2019In: Wireless personal communications, ISSN 0929-6212, E-ISSN 1572-834X, Vol. 109, no 2, p. 715-738Article in journal (Refereed)
    Abstract [en]

    In Internet of Vehicles (IoV), numerous routing metrics have been used to assess the performance of routing protocols such as, packet delivery ratio, throughput, end-to-end delay and path duration. Path duration is an influential design parameter, among these routing metrics, that determines the performance of vehicular networks. For instance, in highly dynamic scenarios, it can be used to predict link life time in on-demand routing protocols. In this paper, we propose an infrastructure-assisted hybrid road-aware routing protocol which is capable of enhanced vehicle-to-vehicle and vehicle-to-infrastructure communication. A remarkable aspect of the proposed protocol is that it establishes a link between path duration and fundamental design parameters like vehicular velocity, density, hop count and transmission range. Although, a lot of research has been previously performed, a well defined analytical model for IoV is not available in the literature. Precisely, a relation between path duration and vehicular velocity has not been validated in the previous studies. Experimental results show that the increased packet delivery ratio with reduced end-to-end delay can be achieved by the prediction of path duration. Proposed model for path duration is validated by getting experimental results from network simulator 3 (NS3) and analytical results from MATLAB. In addition, SUMO simulator was used to generate real time traffic on the roads of Gangnam district, South Korea.

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  • 49.
    Abbas, Muhammad Tahir
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Muhammad, Afaq
    Sarhad Univ Sci & Informat Technol, Pakistan.
    Song, Wang-Cheol
    Jeju Natl Univ, South Korea.
    SD-IoV: SDN enabled routing for internet of vehicles in road-aware approach2019In: Journal of Ambient Intelligence and Humanized Computing, ISSN 1868-5137, E-ISSN 1868-5145, Vol. 11, no 3, p. 1265-1280Article in journal (Refereed)
    Abstract [en]

    Proposing an optimal routing protocol for internet of vehicles with reduced overhead has endured to be a challenge owing to the incompetence of the current architecture to manage flexibility and scalability. The proposed architecture, therefore, consolidates an evolving network standard named as software defined networking in internet of vehicles. Which enables it to handle highly dynamic networks in an abstract way by dividing the data plane from the control plane. Firstly, road-aware routing strategy is introduced: a performance-enhanced routing protocol designed specifically for infrastructure-assisted vehicular networks. In which roads are divided into road segments, with road side units for multi-hop communication. A unique property of the proposed protocol is that it explores the cellular network to relay control messages to and from the controller with low latency. The concept of edge controller is introduced as an operational backbone of the vehicle grid in internet of vehicles, to have a real-time vehicle topology. Last but not least, a novel mathematical model is estimated which assists primary controller in a way to find not only a shortest but a durable path. The results illustrate the significant performance of the proposed protocol in terms of availability with limited routing overhead. In addition, we also found that edge controller contributes mainly to minimizes the path failure in the network.

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  • 50.
    Abbas, Shahrukh
    et al.
    National University of Sciences & Technology, PAK.
    Kazmi, Syed Ali
    National University of Sciences & Technology, PAK.
    Naqvi, Muhammad
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Javed, Adeel
    National University of Sciences & Technology, PAK.
    Naqvi, SR
    National University of Sciences & Technology, PAK.
    Ullah, Kafait
    National University of Sciences & Technology, PAK.
    Khan, Tauseef
    Natl Transmiss & Dispatch Co NTDC, PAK.
    Shin, Dong
    SungKyunKwan Univ SKKU, KOR.
    Impact Analysis of Large-Scale Wind Farms Integration in Weak Transmission Grid from Technical Perspectives2020In: Energies, E-ISSN 1996-1073, Vol. 13, no 20, article id 5513Article in journal (Refereed)
    Abstract [en]

    The integration of commercial onshore large-scale wind farms into a national grid comes with several technical issues that predominately ensure power quality in accordance with respective grid codes. The resulting impacts are complemented with the absorption of larger amounts of reactive power by wind generators. In addition, seasonal variations and inter-farm wake effects further deteriorate the overall system performance and restrict the optimal use of available wind resources. This paper presented an assessment framework to address the power quality issues that have arisen after integrating large-scale wind farms into weak transmission grids, especially considering inter-farm wake effect, seasonal variations, reactive power depletion, and compensation with a variety of voltage-ampere reactive (Var) devices. Herein, we also proposed a recovery of significant active power deficits caused by the wake effect via increasing hub height of wind turbines. For large-scale wind energy penetration, a real case study was considered for three wind farms with a cumulative capacity of 154.4 MW integrated at a Nooriabad Grid in Pakistan to analyze their overall impacts. An actual test system was modeled in MATLAB Simulink for a composite analysis. Simulations were performed for various scenarios to consider wind intermittency, seasonal variations across four seasons, and wake effect. The capacitor banks and various flexible alternating current transmission systems (FACTS) devices were employed for a comparative analysis with and without considering the inter-farm wake effect. The power system parameters along with active and reactive power deficits were considered for comprehensive analysis. Unified power flow controller (UPFC) was found to be the best compensation device through comparative analysis, as it maintained voltage at nearly 1.002 pu, suppressed frequency transient in a range of 49.88-50.17 Hz, and avoided any resonance while maintaining power factors in an allowable range. Moreover, it also enhanced the power handling capability of the power system. The 20 m increase in hub height assisted the recovery of the active power deficit to 48%, which thus minimized the influence of the wake effect.

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