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This paper addresses challenges with modelling of segmented power cable conductors using finite element analysis (FEA) for ampacity calculation. Segmented conductors improve current distribution by minimizing skin and proximity effects, thus reducing conductor losses. 2D FEA simulation offers high flexibility and accuracy beyond IEC 60287 for complex laying geometries, but the modelling of losses in segmented constructions using FEA has proven difficult due to the big difference in wire size and twisting pitch, requiring great amounts of computational power. In this paper a hybrid method is proposed, in which the IEC 60287 empirical formulae for segmented conductors are included in a 2D FEA model. The proposed method shows a good correspondence to IEC standard calculations, with deviations in conductor AC resistance of less than 1 %. Hybrid Method for Numerical Implementation of Segmented Power Cable Conductors in Finite-element Based Ampacity Calculation

Denne masteroppgaven utforsker muligheten for å bruke dyp forsterkende læring (eng. deep reinforcement learning, DRL) til å utvikle et autonomt dokkingsystem for en underaktuert overflatefarkost. Autonome marine fartøy er for tiden populære innen forskningsmiljøer og har vist potensiale til å både øke sikkerheten og redusere driftskostnader. Det har blitt presentert flere løsning for dokking av fullaktuerte overflatefarkoster. Problemet for dette prosjektet er at farkosten kun er drevet av to fastmonterte propeller i akter, noe som gjør den underakturert. Dette introduserer et interessant kontrolproblem siden dette dramatisk reduserer manøvrerbarheten og gjør dynamisk posisjonering nærmest umulig. For å løse dette ble et maskinlæringsmiljø som inneholder farkostens dynamikk utviklet. To DRL-algoritmer ble implementert og sammenlignet; deep deterministic policy gradient (DDPG) og proximal policy optimization (PPO). Begge algoritmene ble trent med den samme belønningsfunksjonen, en funksjon som belønner DRL-agenten etter hvor godt den tilfredstiller kravene for posisjon og orientering. Resultatene viste at PPO utførte dokkingen bedre og ble dermed brukt til videre forsøk. Realistisk målestøy og havstrømmer ble lagt til i maskinlæringsmiljøet for å forberede DRL-agenten for testing på en virkelig farkost. To modeller ble trent, en med ukjente havstrømmer og en med DVL-målte havstrømmer. Simuleringsresultatene viste at det er mulig å utvikle en dokkingkontroller ved å bruke maskinlæring. Begge modellene klarte å håndtere havstrømmer opp til 0.2 m/s, men etterhvert som havstrømmene nådde 0.5 m/s var dokkingkontrolleren avhengig av målinger av havstrømmene for å klare å dokke. Arbeidet i denne masteroppgaven har presentert en dokkingkontroller som er vellykket i et simulert mijø, men på grunn av forenklinger i oppgaven er det nødvendig med mer utvikling før det kan brukes på en virkelig farkost. This thesis aims to use deep reinforcement learning (DRL) to develop an autonomous docking system for an underactuated Unmanned Surface Vessel (USV). The field of autonomous marine vessels is currently a hot topic and has shown the potential to increase safety and reduce the costs of operation. Various solutions for autonomous docking have been presented for fully actuated ships. However, the USV of interest in this thesis is only controlled by two fixed propellers in the rear, making it underactuated. This introduces an interesting control problem since it dramatically reduces the maneuverability and makes dynamic positioning nearly impossible. To address this, a machine-learning environment with the USV's dynamics was developed. Two DRL algorithms were implemented and compared, namely deep deterministic policy gradient (DDPG) and proximal policy optimization (PPO). Both algorithms were trained with the same reward function, which rewards the reinforcement-learning agent based on how well it reaches the desired position and orientation. It was found that PPO performed better and was therefore used for further development. Realistic measurement noise and ocean current disturbance were added to the environment to prepare the DRL agent for a real-world application. Two models were trained, one with unknown ocean current and one with DVL measured ocean current. The results of the simulations show that a docking controller is feasible with the use of machine learning. Both the model with and without DVL measured ocean current could handle ocean currents up to 0.2 m/s. However, as the ocean currents reached 0.5 m/s, the control system was dependant on measured ocean currents to achieve a stable docking maneuver. The work of this thesis has presented a docking system that is successful in a simulated environment. However, due to simplifications in this thesis, a solution for real-world applications still needs further work.

Norsk Hydro ASA er en global produsent og leverandør av aluminiumsprodukter og -løsninger. Hydro har en verdensomspennende og kompleks verdikjede preget av mange aktører og flere forretningsområder, der bauksitt og alumina, energi, primærmetall og valsede og ekstruderte aluminiumprodukter står sentralt. Dagens logistikksituasjon ved norsk virksomhet er preget av fem store smelteverk med totalt 3,7 millioner tonn inn- og utgående materialer. 95\% av produktene skal fraktes på sjø og gir ca. 1400 ordre til havner til ca. 400 kunder fordelt på 25 ulike land, med om lag 119 millioner dollar i fraktkostnader. Hydro har det siste året jobbet med et større forbedringsprosjekt knyttet til logistikk og verdikjedestyring, der målsettingen er å redesigne hele metoden for logistikk og vareflyt, fra fabrikk til kunde. Sentralt her er implementering av lastebærere for aluminiumsproduktene, også kalt kassetter. Alle produkter, både inngående og utgående flyt, distribueres på slike lastbærere og benyttes for både intern og ekstern distribusjon. Årlig distribusjonsvolum er estimert til å ligge mellom 1,35 –1,65 millioner tonn, og kapasiteten til kassettene varierer ut ifra hvilket produkt som fraktes. Det er vesentlig for Hydro at det er en 100\% tilgjengelighet på slike kassetter. På bakgrunn av dette har studenter ved NTNU fått i oppgave å utvikle en simuleringsmodell som skal gi et estimat på et nødvendig antall kassetter i drift, som tilfredsstiller krav til blant annet kapasitet, tilgjengelighet, vareflyt, servicegrad og forventet rotasjon av kassetter i systemet. Det antas å være et behov på mellom 1000 og 1500 kassetter. Det har også blitt utført en sensitivitetsanalyse som skal studere sammenhengen mellom parametre, og i hvilken grad det vil påvirke flyten av kassetter i systemet. Resultatetene fra simuleringsmodellen som er utviklet i denne bacheloroppgaven kan benyttes av Norsk Hydro som en indikasjon på antallet kassetter som bør investeres i. En storskala simulering av operasjonsprosessene skal legge til rette for en veloverveid beslutning. Norsk Hydro ASA is a global manufacturer and supplier of aluminium products and solutions. Hydro has a worldwide and complex value chain characterised by many players and several business areas, such as bauxite and alumina, energy production, primary metal and rolled and extruded aluminium products. Today's logistics situation for Norwegian operations is characterised by five large smelters with a total of 3.7 million tonnes of incoming supplies and outgoing materials. 95\% of the products are to be transported at sea with approximately 1400 orders for ports including 400 customers across 25 different countries, with about \$119 million in shipping costs. The past year, Hydro has been working on an improvement project related to logistics and supply chain management, where the goal is to redesign the logistics operations and flow of goods, from factory to customer. An important aspect to the improvement is the implementation of load carriers for the aluminium products, called cassettes. All products, both inbound and outbound, are to be distributed on cassettes and are used for both internal and external distribution. The annual distribution volume is estimated to be between 1.35 - 1.65 million tonnes, and the capacity of the cassettes varies based on the product being shipped. It is essential for Hydro that there is a 100\% availability on such cassettes. Therefore, students at NTNU have been tasked with developing a simulation model that will provide an estimate of the required number of cassettes in operation, which meet requirements for capacity, availability, flow of goods, service level and expected rotation of cassettes in the system. The need for cassettes is estimated to be between 1000 and 1500 cassettes. A sensitivity analysis has also been performed to study the relationship between parameters and the extent to which it will affect the flow of cassettes in the system. The results from the simulation model developed in this bachelor thesis can be used by Norsk Hydro as an indication of the number of cassettes that should be invested in to fully operate the system. A large-scale simulation of the operation processes should facilitate a well-considered decision.

Bakgrund: Offentlig sektor har under de senaste decennierna genomgått omfattande omorganiseringar och reformer som syftat till att göra den allmänna välfärden mer effektiv. Enligt tidigare forskning har dock dessa reformer inte varit tillräckligt bra anpassade för offentlig sektor. Influenser hämtade från det privata näringslivet har medfört konsekvenser för såväl arbetssätt, de samhälleliga intressena och inte minst medarbetarnas arbetssituation. Med utgångspunkt i denna bakgrund har studien följande problemformulering: Vad anser medarbetare inom offentlig sektor är ett hållbart syn- och arbetssätt och kan det innebära en förening av den offentliga traditionen och influenser från den privata sektorn? Syfte: Syftet med denna studie är att ur ett medarbetarperspektiv utforska innebörden av ett hållbart syn- och arbetssätt inom offentlig sektor samt vart detta tar sin utgångspunkt. Metod: Studien har utgått från en kvalitativ metod för insamling av empiriskt material. Detta har skett genom 10 semistrukturerade intervjuer med medarbetare som är verksamma inom kommuner och region, geografiskt avgränsat till Västra Götalands län. Resultat och analys: Studiens resultat presenteras genom en tematisering efter fem övergripande områden som författarna identifierat som återkommande i samtalen. Dessa är: effektivisering, styrning, tillit, vikten av att värna om medarbetaren samt förskjutning av arbetsuppgifter. I analysen bekräftas och dementeras studiens resultat av tidigare forskning och här synliggörs därtill förslag till förbättringar ur ett medarbetarperspektiv. Slutsatser: Studien visar att ett hållbart syn- och arbetssätt bland annat inkluderar tillit till medarbetaren, likabehandling och rättvisa med en hög grad av autonomi och professionell logik i arbetssättet. Medarbetare inom offentlig sektor är öppna för arbetssätt som influerats av dess omvärld. Background: The public sector has during the last decades been transformed by reorganizations and reforms which purpose has been to make the public welfare more efficient. According to earlier research these reforms has not been sufficiently adopted for the public sector. Influences derived from the private sector have had consequences for both the working methods, the social interests and, in particular, the employees' work situation. With that as a starting point, this study will attempt to answer: What does employees within the public sector consider to be a sustainable approach and working methods and can the traditional public sector uniting with influences from the private sector? Purpose: The purpose of this study is to discuss the meaning of a sustainable approach and working methods within the public sector with an employee point of view and where this is based. Method: The study is based on a qualitative method for collecting empirical material. This included 10 semi-structured interviews with employees working in municipalities and regions, geographically bound to Västra Götalands län. Results and analysis: The result of the study will be presented in five headings based on reoccurring themes identified by the authors during the interviews. These are: efficiency, control, trust, value of employees and the shift of assigned working tasks. The analysis both confirms and denies previous research and submits suggestions for improvements from an employee point of view. Conclusions: The study shows that a sustainable approach and working methods include trust in the employee, equal treatment and justice with a high degree of autonomy and professional logic in the working methods. Public sector employees are open to working practices influenced by their outside world.

För små företag utan rekryteringsansvarig person kan det var svårt att hitta rätt personal. Brist på sådana resurser är en påfrestning som leder till stress och mindre lyckade rekryteringar. Målet med arbetet var att hitta en lösning för att automatisera matchning i en rekryteringsprocess genom att ge förslag på relevanta personer som tidigare sökt jobb hos företag via Cheffle:s tjänst. Det finns flera olika sätt att matcha uppsättningar av data. I det här fallet användes maskininlärning som lösningsmetod. Detta implementerades tillsammans med en prototyp som hämtade in data om jobbet och den arbetssökande. Maskininlärningsmodellerna Supportvektormaskin och Artificiella Neural Nätverk använde sig av denna data för att betygsätta de arbetssökande. Detta utifrån hur väl de matchade jobbannonsen. Arbetets slutsats är att ingen modell hade tillräckligt hög precision i sina klassificeringar för att användas i en verklig implementation, detta då endast små mängder testdata fanns tillgänglig. Resultatet visade att maskininlärningsmodellerna Supportvektormaskin och Artificiella Neurala Nätverk visade potential för att kunna användas vid denna typ av matchning, men för att fastställa detta krävs mer träningsdata It can be hard for a small company with no dedicated HR-role to find suiting recruits. A lack of resources takes a toll on the existing employees and increase stress that further harms recruiting. The goal of this work was to find a solution to automate matching in a recruitment process by suggesting relevant applicants that have previously used Cheffle. There are multiple ways of matching data. In the case of this study, machine learning was used. A prototype was developed. It collected data about a job and its related applicants. The data was then used by the machine learning models Support vector machine and Artificial Neural Network to classify the applicants by how closely they match the job position. The conclusion made in this work is that no model had a precision high enough in its classification to be used in a final implementation. The low precision in classification is likely a result of the small amount of test data available. The result showed that the machine learning models Support vector machine and Artificial Neural Network had potential in this type of matching. To firmly determine this the models would need to be tested with more test data.

Problem background and problem discussion: The increased demands on companies and their ability to operate sustainably has made corporate social responsibility (CSR) a very hot topic in modern society. The academic debate has yet to put a definite answer on whether the engagement in CSR activities has a positive effect on a company financially. Previous research on stock listed in Sweden indicate that there is a positive relationship between environmental performance and that there is an asymmetry in how it is valued across company sizes. However, there has not yet been any research made into what impact size has on the value relevance of social CSR ratings. This will be tested by drawing from resource-based theory and legitimacy theory. Research question: How is the value relevance of social ratings affected by accounting for company size? Purpose: The purpose is to examine what effect the inclusion of corporation size has on the value relevance of social CSR ratings. Theory: The study primarily utilizes Stakeholder theory, the resource-based theory and legitimacy theory. Method: This is a quantitative study in a panel data setting with a deductive research approach. The practical method is a regression analysis that assesses the value relevance of CSR measures at the OMX Stockholm for the years of 2006, 2007, 2008, 2009, 2011 and 2013. The study encompasses 349 Small-, medium- and large-sized companies and has a total of 1429 observations, which have been subject to statistical significance tests. Results and analysis: The results show that social, environmental and overall CSR ratings are value relevant and associated with lower market values. There also seems to be little impact on results by including company size as a variable. Furthermore the results of this study differ from previous research, implying that results are very sensitive to changes in the regression model. Conclusion: The results of the study lead us to believe that size has little impact on how value relevant social ratings are. This implies that regardless theory such as the resource-based and legitimacy theory these cannot be supported in practice among Swedish firms listed at OMX Stockholm. Furthermore, our method gives different results with regard to previous research done on the Swedish market and indicates that there is a negative relationship between CSR ratings and market value.

Utviklingen innen fagfeltene Informasjonsteknologi (IT) og Geografiske Informasjonssystemer (GIS) er stor og med dette åpnes mange muligheter for MilGeo i Hæren. HVS ser muligheten til å automatisere en del av arbeidsprosessene til de som jobber i fagfeltet. Spesifikt er det ønskelig med en fullstendig automatisering av Etterretningsvurdering trinn 2 (E-vurdering trinn 2) og dette vil bidra til å frigjøre tid slik at analytikerne kan støtte med vurderinger i enda større grad. GIS består av en teknisk og en menneskelig del. I denne oppgaven har vi valgt å se på den tekniske delen og muligheter for å automatisere den. Vi har kommet frem til følgende problemstilling: Hvordan kan Etterretningsvurdering trinn 2 automatiseres for MilGeo i Hæren? Det empiriske grunnlaget kommer primært fra intervjuer med fagpersonell i Ingeniørbataljonen (INGBN), i tillegg har vi hatt samtaler med HVS for å kartlegge behov. En kombinasjon av faglig standpunkt og tilegning av relevant kunnskap har hjulpet oss til å produsere et teknisk forslag som danner grunnlaget for automatisering av E-vurdering trinn 2. Det konkluderes med at en E-vurdering trinn 2 kan automatiseres med et produkt som er en kombinasjon av tilrettelagt data og ren teknisk automasjon. Produktet er vedlagt oppgaven med en forklaring til oppbygning, bruk og hvordan skriptverktøyet kan endres.

Wear of starved oil-lubricated heavily loaded, oscillating journal bearings, which operates at low sliding speed and under dynamic load, was studied. These bearings were normally intermittently lubricated by grease or oil. No distinct difference in wear rate could be discerned between the CuSn12 reference and CuSn8Ni15 sample bushings. Since the oil flow and pressure were low, most of the oil escaped from the contact, resulting in metal-to-metal contact between pin and bushing, and yielding initial adhesive wear that quickly evolved into abrasive wear. Due to the relative high surface roughness and hardness of the pin, the system did not perform well as bearing.

Denne avhandlingen omhandler segregasjon blant rike i Oslo. Oppgaven vil prøve å svare på om det har funnet sted en økt segregasjon av denne gruppen i tidsrommet 1989-2003, og hvilke bydeler som i så fall er mest berørt av disse endringene. Avhandlingen er en kvantitativ oppgave som bygger på sekundære kilder. Rent konkret handler det om inntektsklasser fordelt på bydeler, utarbeidet av SSB for Utviklings- og kompetanseetaten, Oslo kommune. Problemstillingene blir besvart gjennom bruk av segregasjonsindeksen og lokaliseringskvotienten. Mine funn er ikke entydige. Hvis man ser på den rikeste tidelen av inntektstakerne for perioden finner jeg en økt segregasjon i Oslo. Jeg finner også at andelene av den rikeste tidelen vokser i alle byområder, med unntak av ytre øst som minsker sine andeler. Hvis man derimot ser på gruppene i forhold til reell kjøpekraft har det ikke funnet sted en økt segregasjon. Jeg finner en økning i andeler rike i de indre byområdene, mens de ytre bydelene minsker sine andeler. Byen er sosialt delt. I begge tilfeller finner jeg en overrepresentasjon i de vestlige bydelene, og en underrepresentasjon i de østlige. Utviklingen for den rikeste andelen går i retning av økte forskjeller mellom øst og vest. Hvis man derimot ser på kjøpekrafts- gruppene viser den at ytre vest har en negativ tilvekst, mens indre øst har en positiv tilvekst.

Grease-lubricated journal bearings present a common challenge for construction equipment manufacturers in the world. The common design methodology is based on empirical data and has worked very well historically because the market and governments have accepted that bearings in construction equipment need frequent lubrication and exchange of worn parts. Legal and market requirements will soon demand lower environmental impact and increased machine efficiency. These requirements call for better methods of designing grease lubricated journal bearings. The goal of the outlined work was to develop better design methods for grease lubricated journal-bearing design used in heavy-duty construction equipment machines, in order to prolong life and lubrication intervals. The research approach of the project can roughly be divided into three phases: 1. Development of test apparatus and test methods for journal bearing studies. 2. Bench tests of grease lubricated journal bearing design. 3. Verification between bench tests and computer simulations. In the thesis the current state of the art in bearing design for construction equipment is discussed and summarized in the form of design guidelines. The suggested design steps are just a mean to get to the starting point of design. The simple guidelines do however serve a purpose when collected since most published bearing design guidelines are aimed at the bushing material or at continuously rotating bearings. The influence of housing, environment and load cases can not be ignored when designing a bearing. Long term field-testing and experience can not be replaced until better design criteria have been established. Paper A deals with the design of the bearing test apparatus that was built and evaluated. Comparisons between theoretical contact and contact elements in Finite Element program have been made and discussed in paper B. In paper C a replica technique for measuring wear of large field specimens was evaluated. A case study of bearing housing design was performed in paper D utilizing Finite Element program and then validated in paper E in the bearing test apparatus. The influence of grease groove design on bushing life was tested and evaluated in paper F. Wear simulation of a plain bushing has been performed with a Finite Element program and presented in paper G. QC 20100930