Forest Land Ownership Change in Europe. COST Action FP1201 FACESMAP Country Reports : Joint Volume

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Evaluation of Switching Characteristics, Switching Losses and Snubber Design for a Full SiC Half-Bridge Power Module

In this thesis, the performance of the full Silicon Carbide (SiC) half-bridge power module BSM120D12P2C005 from Rohm Semiconductor is investigated. A laboratory circuit enabling double-pulse tests of the half-bridge module is designed and built. Building such a laboratory circuit demands careful analysis of the challenges and dangerous aspects that might arise. Consequently, the first part of the thesis discusses relevant background theory on SiC material properties, SiC MOSFETs and SiC SBDs. This is followed by general theory on different power converters, as well as analysis of switching transients and power losses in MOSFETs and SBDs. A theoretical efficiency comparison of three-phase inverters consisting of eight different state-of-the-art SiC half-bridge modules and one state-of-the-art Si IGBT half-bridge module is provided. It is shown in this comparison that all the SiC modules achieve an efficiency of 98 %, while the Si IGBT module gives an efficiency of approximately 93 % at 50 kHz. Subsequently, general theory on important considerations when designing a converter circuit for hard-switching SiC modules is presented. This is followed by a detailed description of the laboratory setup, the measuring instruments and other important considerations in this thesis. The next part presents an analysis of the SiC module performance through simulations in LTspice IV. The simulation circuit design and decisions are justified. The simulations are used as basis to investigate the switching characteristics of the SiC module, in addition to testing the impact of changes in the laboratory circuit. It is found through simulations that the combination of a DC snubber and a turn-off snubber could help improve the switching characteristics. Finally, results from the laboratory experiments are presented. Firstly, it is shown that the bandwidth and stray inductance of the measuring instruments influence the switching characteristics. This is followed by a discussion on the selection of gate resistance and its influence on the switching speed. A short-circuit protection (SCP) is added to the gate driver of the SiC MOSFET, and its practical operation is proven successful. The switching characteristics and switching losses are obtained through double-pulse tests of the SiC MOSFET, and are presented for different drain-to-source voltages and drain currents. The switching characteristics show high switching stresses on the SiC module. Thus, snubber circuits are added to the laboratory circuit. The addition of a DC snubber and a turn-off snubber results in 40 % reduction in voltage overshoot and 85 % reduction in ringing duration. This improvement is achieved with an increase in total switching losses of 24 %. It is found that an Si IGBT switching at 600 V 120 A and a switching frequency of 50 kHz dissipates four times more energy than a SiC MOSFET including snubbers at equal conditions

Representations of linguistic variation in audiovisual translation : a study of American animated films and their Norwegian dubbed translations

This thesis examines how dialects and accents are represented in Norwegian dubbed translations of American animated films for children, and how this can be explained from a sociolinguistic perspective. Twelve films released between 2009 and 2013 were analyzed. An interdisciplinary approach to translation studies, involving theory and research on language attitudes and standard language ideology, form the theoretical backdrop for the analysis. A quantitative approach to the material found that standard varieties dominate in source and target texts and that standardization is a prevalent strategy. The qualitative analysis further indicates that translation by stereotypes is frequently resorted to, and that the translations tend to give priority to the negotiation of target culture linguistic stereotypes over fidelity to source text variety. The results are discussed in light of differences between sociolinguistic situations in source and target cultures, with a particular emphasis on the role of language attitudes in the process and product of dubbed texts, specifically texts aimed at children

Binary Classification, Logistic and Nominal Regression: Application to Bank Customer Loyalty Data

Kunder er grunnlaget for enhver forretning sin suksess, og en forretning kan aldri være for takknemlig for sine trofaste kunder. I denne masteroppgaven skal vi finne signifikante forskjeller mellom ulike typer kunder. Ved å gjøre dette kan vi få nyttig kundeinnsikt av passive kunder, og forstå hvorfor kunder velger å gå fra å være aktive til å bli inaktive kunder. Analysene er gjort på kundedatabasen til banken som denne oppgaven er skrevet for. Bankkundene er delt inn i seks grupper, eller kategorier, basert på kundeaktivitet og antall bankprodukter tatt i bruk. Vi betegner kategoriene som A-F, hvor kategori A står for kundene som er mest aktive og kategori F står for kundene som er minst aktive. Vi bruker nominal regresjon til å finne forskjeller i hver av disse kategoriene. Vi fant ut at kunder som har vært i en søkeprosess for lån eller kredittkort hadde en større sannsynlighet for å være en kunde av kategoriene A og B. Vi fant også ut at sannssynligheten for å være kategorisert i F er sterkt redusert hvis kunden er medlem eller ikke-medlem med medlemsbetingelser. I tillegg, sannsynligheten for å være en kunde av kategori A økes kraftig dersom kunden har aktivert eFaktura. La kategoriene A-D være kategoriene med aktive kunder, og kategoriene E-F være kategoriene med inaktive kunder. Vi lager en indikatormodell som forutser hvilke kunder som går fra å være aktive til å bli inaktive i fremtiden. Vi utfører statistiske modellerings- og læringsmetoder, som binær logistisk regresjon, "random forests" og XGBoost, for å oppdage disse kundene. Vi tester også forskjellige modeller basert på modellseleksjonsmetoder som bruker Akaike informasjonskriterium (AIC), lasso regularisering og viktighet av variabler. Modellkvaliteten er evaluert på AUC-verdien på test data. Modellen som presterte best var XGBoost-modellen med alle variablene inkludert. Dermed vil denne modellen bli brukt som indikatormodellen, m.a.o. modellen som skal forutse om en aktiv bankkunde holder seg aktiv eller blir inaktiv i løpet av det kommende året. Vi erfarte at innskuddssaldoen til kunden var den mest signifikante variabelen i denne analysen. Den logistiske regresjonskoeffisienten for denne variabelen er negativ, som betyr at jo høyere innskuddsaldoen er, desto lavere sannsynlighet er det for å bli inaktiv i fremtiden. Antall transaksjoner av kunden og om kunden har lån, er også svært viktige faktorer som spiller inn.Customers are the foundation of any business's success, and a business can never be too grateful for loyal customers. Customer insight is therefore an important key to help sustain loyal and active customers. In this thesis we are going to detect significant differences between different customer types, as well as indicating future inactive customers. Doing so, we will get useful insight about the inactive customers, and perhaps understand why they choose to go from being active to being inactive. The analyses are done on a bank customer database, provided by the bank itself. The bank customers are divided into six groups, or categories, based on customer activity and the number products used. The categories are denoted by A-F, where A contains the most active customers and F contains the least active customers with no products used. We perform nominal regression in order to detect differences between these groups. We experienced that customers that have applied for loan/credit card are more likely to be customers from the categories A and B. Furthermore, we experienced that probability for being in category F is strongly decreased if the customer is a member or a non-member with member benefits. Also, the probability for being in category A is significantly increased if the customers have activated electronical billing. Let the categories A-D relate to the active customers, and the categories E-F relate to the inactive customers. To indicate customers that are going to be inactive in the future, we create an indicator model. We perform statistical modelling and learning methods, such as binary logistic regression, random forests and XGBoost, in order to create this model. We use model selection methods, such as the Akaike Information Criterion (AIC), lasso regularization and variable importance. The performance of a model is evaluated on the AUC value on test data. The model that performed best was the XGBoost model with all the variables included. Thus, this will be used as the indicator for detecting bank customers that are going to be inactive within the next year. We experienced that balance of the customer was clearly the most significant variable, when it comes to being active or inactive in the future. The binary logistic regression coefficient for this variable is negative. Hence, the higher the balance on the deposit account of a customer, the lower is the probability for being inactive in the future. The number of transactions of the customer and if the customer has a loan, are both also very important factors when it comes to being active/inactive in the future

A methodology for optimal placement of energy hubs with electric vehicle charging stations and renewable generation

The use of electric vehicles and renewable energy sources can significantly contribute to the reduction of pollution levels, fostering a cleaner and more sustainable environment. In addition to their positive environmental impact, electric vehicles can also serve as energy storage units, enabling a bidirectional energy flow between the vehicles and the grid. Despite these promising prospects, a disjointed approach to charging infrastructure planning overlooks the synergies between the energy and transportation ecosystem. This calls for a holistic and coordinated approach to infrastructure development that harnesses the benefits emerging from the convergence of electric vehicles, renewable energy, and transport planning. This paper presents a methodology for the optimal placement of future Energy Hubs for electric vehicle charging and renewable generation. The methodology uses data from open-source datasets involving renewable energy sources, traffic density, charging patterns, road topology, and land use. The optimization problem is formulated as a multi-objective linear programming problem, with the objectives of minimizing the number of Energy Hub units, minimizing electric vehicles charging radius coverage and distance from power substations, and maximizing energy generation. The methodology is demonstrated through an application in Trondheim, Norway, which produces a Pareto front for decision-makers to evaluate the best trade-offs between objectives.A methodology for optimal placement of energy hubs with electric vehicle charging stations and renewable generationpublishedVersio

“Ingen har kalt meg eldre arbeidstaker før”: En kvalitativ studie av hvordan eldre arbeidstakere opplever de siste årene i arbeidslivet

Målet med denne studien er å belyse hvordan eldre arbeidstakere opplever sine siste år i arbeidslivet og hva som fortsatt holder dem i arbeid, til tross for muligheten til å trå inn i pensjonisttilværelsen. Selv om myndighetene satte inn tiltak mot tidligpensjonering fra starten av 2000-tallet, bærer arbeidslivet fortsatt preg av utfordringer rundt holdninger til eldre arbeidstakere. Dersom den gjennomsnittlige avgangsalderen synker vil det gi store samfunnsøkonomiske konsekvenser. Med denne studien ønsker jeg å gi et bidrag til en mer opplyst offentlig debatt som dernest kan gi bedre tiltak for å holde eldre lenger i arbeid. Dette er essensielt for å opprettholde velferdsstaten slik vi kjenner den i dag. Tidligere kvantitativ forskning på eldre arbeidstakere fokuserer blant annet på miljøfaktorer i ulike yrker og sektorer. Med dette prosjektet forsøker jeg med bruk av kvalitative intervju å gå dypere i forskningsfeltet og belyse nye sider av saken.  Analysen tar utgangspunkt i åtte dybdeintervjuer av arbeidstakere mellom 60 og 70 år i ulike yrker og sektorer. I analysen benyttes sosialkonstruktivisme som et overordnet rammeverk og utgangspunkt for forståelsen av eldre arbeidstakeres opplevelse av arbeidslivet. Eldre arbeidstakere opplever for det første omstilling, egenutvikling og oppdatering som muligheter i arbeidslivet. Videre identifiserer jeg fleksibel arbeidstid både som en mulighet og begrensning for arbeidstakerne. Andre utfordringer som de eldre arbeidstakerne skisserer er slitenhet, digitale utfordringer og forekomst av stigmatisering på grunn av alder. Mine funn indikerer at å være en bidragsyter, oppleve mestringsfølelse, være ønsket av ledelsen og ha autonomi er avgjørende faktorer for at de eldre arbeidstakerne fortsatt er i arbeid. Oppsummert belyser denne studien hvordan de eldre arbeidstakeres opplevelse av sine siste år i arbeidslivet varierer ut fra kontekst og arbeidsvilkår.The aim of this study is to illustrate how senior workers experience their last years as workers and why they still work despite of having the option to retire. Regardless of numerous efforts to combat early retirement since the early 2000s, the working life is still affected by prejudices and attitudes towards this employee group. A lower retirement age will cause severe socio-economic losses. In this thesis I contribute to an enlightened public debate that can provide better measures to keep the elderly in work, which is essential maintaining the welfare system as we know it. Previous quantitative research on senior workers focus on environmental factors in various professions and sectors. In this study, with help of qualitative interviews, I try to go deeper into this research field and examine aspects that have not received much academic attention yet.  The analysis is based on eight in-depth interviews with workers between the ages of 60 and 70 in various professions and sectors. In the analysis, social constructivism is the overall theoretical framework for understanding senior workers´ experiences in working life. Senior worker perceive adaption, self-development and refreshing of knowledge as opportunities in their working life. Furthermore, I identify flexible working hours as both an opportunity and a limitation for the senior workers. Other challenges the senior workers outline are fatigue, digital challenges and the occurrence of stigma due to their age. My findings suggest that being a contributor, being desired by the employer, sense of achievement and autonomy are elements that are crucial for the senior workers still being working. To summarise, this study illustrates how the senior workers’ experiences of their last years in working life varies based on context and working conditions.

MPC-based Voltage Control with Reactive Power from High-Power Charging Stations for EVs

The recent development of EVs with high-capacity batteries and high charging power capabilities leads to an increased demand for fast-charging stations (FCS). However, FCS can cause power quality issues such as voltage drops in distribution grids with limited power capacity. Grid reinforcements are a standard solution for solving power quality issues. However, these can be costly. An alternative approach is to install bi-directional chargers at FCS and use this flexibility source to provide voltage support in peak-load periods by injecting reactive power to the grid. This paper proposes a model predictive controller (MPC) to control and coordinate such high-power chargers. The MPC maximizes the charging rate for the EVs while ensuring that the voltage level stays within the allowable limits. The control system has been evaluated through simulations on a realistic grid model, and the results show that both the FCS and the grid can benefit from utilizing the reactive power.acceptedVersio

«Tilværelsen har aldri besvart mine spørsmål»: En intratekstuell lesning av Dag Solstads Ellevte roman, bok atten

Denne oppgaven presenterer en lesning av Dag Solstads Ellevte roman, bok atten. Et overordnet mål er å arbeide meg frem til en dypere innsikt i det som fremstår som romanens største gåte. Hvordan kan man forstå den bemerkelsesverdige hovedpersonen Bjørn Hansen? Hypotesen er at det ikke er mulig å gripe den fulle forståelsen av romanen ut i fra en tekstimmanent tilnærming. Det er av den grunn jeg argumenterer for en intratekstuell metode, der Solstads romanunivers danner kontekst for lesningen. I praksis betyr det at oppgavens teoretiske grunnlag består av tekster av og om forfatteren. Argumentasjonen for å anvende dette jeg kaller en intratekstuell metode, knytter seg til observasjonen av at det eksisterer en del interne forbindelseslinjer i Solstads forfatterskap. Dette står i kontrast til måten man vanligvis befatter seg med hans produksjon på. Innledningsvis presenterer jeg forfatterskapet slik det er vanlig å gjøre det, før jeg viser at det forekommer en del mønstre som går igjen. Av de konkrete motivene jeg har valgt som fokusområder i hoveddelen er rollespill, kvinnebilder og kulturkritikk. Ut i fra disse forsøker jeg å argumentere for besvarelser på romanens gåte og i tråd med metoden benytter jeg meg av tekster i Solstads produksjon. Annen litteratur skrevet om forfatteren blir også anvendt for å utvide perspektivet og forståelsen

“Why do we need Munch when we have multiplication?”

Bacheloroppgave, grunnskolelærerutdanning, 2013Sammendrag: Innenfor pedagogisk sosialiseringsteori har det lenge vært kjent at kultur spiller en avgjørende rolle for barnets identitetsutvikling. Kultur henviser her til et sett av normer og verdier som gjenspeiler tendenser og tradisjoner etablert i et samfunn. I dagens skole er også et estetisk kulturbegrep gjeldene, blant annet ved et samarbeid med Den kulturelle skolesekken hvor estetiske opplevelser og kulturuttrykk er i fokus. Dessverre har den estetiske dimensjonen av Kunnskapsløftet mistet sitt fokus til fordel for et ytterligere fokus på teoretiske fag, da i håp om å forbedre resultater på nasjonale prøver. Til tross for en slik utvikling er det viktig at det estetiske fokuset ikke forsvinner da dette kan ha en betydning for barnets identitetsutvikling. En velutviklet følelse av identitet hos barnet kan vise seg å ha en stor betydning for barnets motivasjon for læring, og dermed også for barnets læringsutbytte.Summary: Within educational theory, describing a child’s socialization process, it is well known that culture plays an important part in a child’s identity development. The term culture here represents the norms and values established in a society. In today’s school system, an aesthetic concept of culture is current by the collaboration with Den kulturelle skolesekken, where the focus is on aesthetic experiences and cultural expressions. Unfortunately the aesthetic dimension of the curricula has lost its attention in favor of theoretical subjects. This in hope of approving results on national tests. In spite of this development, it is important that the aesthetic dimension of the education stays in focus, because of its impact on a child’s identity development. A well developed sense of identity turns out to have a big impact on a child’s motivation for learning, and therefore also the child’s learning outcome

"Talking through the ball gag": women navigating empowerment and vulnerability in the pursuit of sexual pleasure

Women's sexual pleasure has been traditionally misunderstood and understudied, and studies of women's sexuality often relate to violence and danger, sexually transmitted infections, or unwanted pregnancies. By interviewing eight women, this qualitative interview study explores how women who have sex with men experience sexual pleasure. Two main themes emerged from their narratives: Women experience feelings of empowerment and women experience feelings of vulnerability connected to their pleasure. I found that a pleasure gap exists between the pleasure that the participants talk about and the actual sexual pleasure they are accessing. The women view themselves as sexually empowered and explore pleasure with sex toys, kink, and BDSM play, but do not always access pleasure or communicate their desires to a partner. To close the pleasure gap, my research suggests that women adopt a critical view of sexual empowerment and build ongoing partner communication