En sjanse til en åpen fremtid: Foreldres forpliktelser overfor mulige barn

Filosofi mastergradsoppgaveFILO350MAHF-FIL

A Study of Wind-Wave Interactions using Offshore High-Frequency Wind and Wave Measurements

Masteroppgave i energiENERGI399MAMN-ENER

Interaksjon mellom Bombus terrestris og honningbier i rødkløveråkre reduserer tettheten av andre humler og fører til redusert rødkløveravling

Pollinator dependent crops have increased by 300% the last 50 years. At the same time many pollinator species are declining, including honeybees and bumblebees. Red clover is one of the crops dependent on bees for seed set. It is the single most important leguminous crop for milk and meat production in Norway, but over the last years crops have declined, and insufficient pollination is a likely hypothesis to explain this. Long tongued bumblebees are the most efficient pollinators of this crop, and are simultaneously the bumblebee species declining the most. To improve yields, honeybees and another bumblebee, B. terrestris, is added to fields. Evidence on how this affects the other bumblebee species, especially long tongued species, and yield is conflicting. However, honeybees are considered poorer pollinators of red clover than bumblebees, and B. terrestris is a known nectar robber. The aim of this study was to identify whether competition occurs between honeybees, B. terrestris and other bumblebee species in red clover fields, and how these interactions may affect red clover yield. To that objective the composition of pollinator communities in 40 red clover fields over two years were examined, and estimates for red clover yield were obtained. B. terrestris abundance was manipulated in five fields. The results suggest that B. terrestris act as nectar robbers, facilitating honeybees and other short tongued bumblebees acting as secondary robbers. Honeybees negatively affects abundance of both long and short tongued bumblebees, indicating that competition occurs. Interaction between increased abundance of honeybees and B. terrestris seems to reduces long tongued bumblebee abundance and red clover yield.Avlinger avhengige av pollinatorer har økt med 300% de siste 50 årene. Samtidig er mange av pollinatorene i tilbakegang, blant annet honningbier og humler. Rødkløver er en av avlingene som er avhengig av insektpollinering for å sette frø, og er den viktigste belgveksten for melk- og kjøttproduksjon i Norge. De siste 10-15 årene har det vært nedgang i frøproduksjonen, og mangelfull pollinering er en av de mest sannsynlige årsakene til dette. Langtungede humler er de mest effektive pollinatorene av rødkløver, men er også den humlegruppen i sterkest tilbakegang. For å øke avlingene settes det tidvis ut bikuber og kolonier av B. terrestris. Det Hvordan dette påvirker andre humlearter og avling er noe usikkert, men honningbier antas å være dårligere pollinatorer enn humler generelt, og B. terrestris opptrer ofte som nektarrobber. Målet med denne studien var å finne ut om det finnes et konkurranseforhold mellom honningbier og humler og B. terrestris og andre humlearter, og hvorvidt dette påvirker rødkløveravlingene. Sammensetningen av pollinatorer og rødkløveravling ble derfor undersøkt i 40 rødkløveråkre i to år. Tettheten av B. terrestris ble manipulert ved å sette ut bol i fem åkre. Resultatene antyder at B. terrestris fungerer som primære nektarrobbere i rødkløver åkrene, og at honningbier og andre korttungede humler fasiliteres av denne adferden ved å benytte seg av hullene allerede laget av B. terrestris. Honningbier påvirker tettheten av både langtungede- og korttungede humler negativt, noe som indikerer er konkurranseforhold. Samtidig økt tetthet av honningbier og B. terrestris ser ut til å ha negativ effekt på antall langtungede humler og rødkløveravling.M-ECO

Kayak Drone – a silent acoustic unmanned surface vehicle for marine research

Advancements in technologies have led to a rapid development of unmanned surface vehicles (USV) for marine ecosystem monitoring. The design, size, and scientific payload of the USVs differ as they are built for different purposes. Here, we present the design criteria and detailed technical solutions of a prototype USV which has been built to fulfill the following experimental and operational needs; the USV should be used for inshore and shallow water acoustic monitoring, offshore comparison of echo sounder recordings from the USV and research vessels, monitor natural fish schooling behavior and seabird-fish behavioral interactions. The prototype has been built over a period of 5 years with steadily quality improvements. As the hull is based on an expedition double kayak, the USV is named Kayak Drone, and we aimed at building the Kayak Drone using of-the-shelf hardware and existing open-source software. This allowed for the development of a modular and well-functioning USV at a relatively low cost. The Kayak Drone produces very little noise and in situ experiments show that the Kayak Drone can record echo sounder data of fish near the surface without disturbing their natural distribution and behavior. One in situ study shows that the Kayak Drone could navigate within a couple of meters from swimming puffin and other seabirds without triggering escape. These results demonstrate that the Kayak Drone can be utilized to produce unbiased survey estimates for fish distributed in shallow waters and near the surface, which is very important for many fish stock assessments and managements. Furthermore, it can also be used as a tool to observe the predation by seabirds on fish schools without interfering with their natural interspecific behavior, which traditionally has been very difficult. The use of the Kayak Drone is not restricted to these tasks, and we foresee that the Kayak Drone can be utilized in many different experiments where a silent platform is needed.publishedVersio

Banana Distributions Based on Stochastic Polar Coordinates

A tracking algorithm may employ a probability distribution for object locations at a given time after the last observation. In the two-dimensional case, such a distribution on geographical locations typically takes a curved, oblong shape, a so-called “banana distribution.” One recently proposed version of the banana distribution assigns probabilities to the possible future locations of a moving object for which the original location, speed and direction are known, while subsequent movement is determined by a constant, unknown acceleration and a constant, unknown turn rate with independent, zero-mean Gaussian distributions. Finding the probabilities of locations in such a distribution can be computationally demanding, since there are no functional, closed forms to recover the acceleration and turn rate that would have taken the object to a particular geographical location. In this paper we propose an approximation to the banana distributions above based on polar coordinates, where the angle out to the next observation is normally distri buted with expectation zero, while the distance out to the next observation is also normally distributed, but with parameters given by two functions on the angle. This framework is computationally far more tractable, and we show that remarkably good approximations to the original banana distributions can be achieved by fine-tuning of the two functions on the angle. Finally, we show how to incorporate the additional assumption of an unknown initial direction with a Gaussian distribution. We believe that the framework proposed here, which is closely related to the shape of the distribution, may serve as a suitable framework in which to compare the various other banana-like distributions obtained from different types of assumptions

Impact of Resource Rent Tax on Norwegian Salmon Farming Companies

This thesis investigates the impact of the resource rent tax announcement and its implementation in Norway. The dataset consists of daily returns for eight salmon farming companies. Half of these companies are affected by the tax, while the other half are not affected. Our sample period ranges from August 2, 2022, to February 1, 2023, which covers the announcement and implementation day. By applying a difference-in-differences approach, we measure the causal effect that the resource rent tax had on the returns of the affected companies (companies that operate in Norway), relative to the non-affected companies (those that operate outside of Norway). Our findings reveal a statistically significant, large negative return in the affected companies on the announcement day. Return on implementation day was close to zero. This result is consistent with efficient markets, where only new information should move stock prices

Concept study of modification alternatives for the High Pressure Cap Running Tool

Master's thesis in Industrial economicsThis thesis is a result of a request from Aker Solutions regarding a modification project of a high pressure cap running tool. This tool is used to set and retrieve the high pressure cap from the flow line mandrel when the xmas tree is not installed. Aker Solutions has identified challenges concerning the complexity, costs and time associated with the operation of the tool, and come up with four concepts that may solve these challenges. The task of this thesis is to look into the engineering challenges and the life cycle costs of each of the concepts. The goal is to provide a recommendation for which concept Aker Solutions should pursue through the research question: What is the best-suited modification solution for the Aker Solutions high pressure cap running tool? The four identified concepts that have been analysed and evaluated, seek to solve complexity, cost and time issues concerning the current method of operation, which utilises an umbilical for hydraulic power supply for the tool. The first is a pre-charged accumulator concept, which uses an internal hydraulic reservoir to supply the tool. Concept number two uses a topside hotline to provide the hydraulics. Concept number three uses a subsea hotline from an ROV. Concept number four uses a hotline from a subsea powerpack. The different concepts are analysed and evaluated against the current method on nine different scored and weighted criteria, based on 36 interviews. The criteria reflect the identified issues and are as follows: feasibility, physical parameters, maintainability, reliability, complexity in use, economic impact, development cost and time, degree of risk reduction and environmental impact. These unbiased and weighted criteria scores, reflect the impression of how each criterion’s criticality are perceived in Aker Solutions as an organisation. The analysis and evaluation utilises a Pugh matrix for pairwise comparison as a decision-making tool and delivers a best-suited concept suggestion. Based on this analysis and evaluation the Pugh matrix suggests that the pre-charged accumulator concept is the best alternative, with a significantly better result than the opposed concepts. The Pugh matrix does however not consider which of the “+” rated concepts perform best on each criterion in relation to the other concepts in the matrix. This is addressed in a qualitative evaluation where the pre-charged accumulator concept is compared to the other concepts on each criterion and the nuances are highlighted. It further shows that the pre-charged accumulator concept has a lower life cycle cost that mitigates the slightly lower performance on maintainability and development cost and time. The only innuendo is that it does not reduce risk as much as the hotline subsea concepts. This can however be accounted for with a thorough operational procedure. The conclusion is that the best-suited modification solution for Aker Solutions Subsea high pressure cap running tool is the pre-charged accumulator concept. This contributes with potential savings for Statoil of 72.7 MNOK, increased rig time efficiency of 57.9%, increased redundancy, reduced operational risk and a more eco-friendly solution.Aker Solution

Impact of Resource Rent Tax on Norwegian Salmon Farming Companies

This thesis investigates the impact of the resource rent tax announcement and its implementation in Norway. The dataset consists of daily returns for eight salmon farming companies. Half of these companies are affected by the tax, while the other half are not affected. Our sample period ranges from August 2, 2022, to February 1, 2023, which covers the announcement and implementation day. By applying a difference-in-differences approach, we measure the causal effect that the resource rent tax had on the returns of the affected companies (companies that operate in Norway), relative to the non-affected companies (those that operate outside of Norway). Our findings reveal a statistically significant, large negative return in the affected companies on the announcement day. Return on implementation day was close to zero. This result is consistent with efficient markets, where only new information should move stock prices

En analyse av en institusjonell investor opp mot Markowitz Frontier : prestasjonsvurdering og analyse av en sparebanks plasseringer i perioden 1.1.2007-31.12.2011

Oppgaven anvender porteføljeteori med det formål å evaluere en sparebanks (av hensyn til sparebankens plasseringer i finansmarkedene er identiteten anonymisert) aksjeforvaltning fra 2007 til 2011. Porteføljen evalueres i hovedsak i forhold til Markowitz’ forventning-varians-modell. Dette betyr mer konkret at vi har satt resultatene fra sparebankens forvaltning opp mot teoretisk optimal forvaltning etter Markowitz’ modell. I dette rammeverket inngår også ulike faktormodeller som forsøker å forklare forholdet mellom risiko og avkastning på aksje- eller porteføljenivå. Oppgaven starter med å gi en inngående beskrivelse av dette rammeverket og hvordan akademia og praksis ser på Markowitz’ modell. I tillegg belyses generell portefølje- og finansteori. Videre vurderes sparebankens portefølje opp mot de optimale porteføljene i perioden fra 2007 til 2011. I tillegg til å se hele perioden under ett, har vi også delt den opp i tre deler for å se utviklingen underveis i perioden. I arbeidet med å konstruere en optimal portefølje har vi også kartlagt risikoaversjonen hos de som er eller har vært ansvarlige for aksjeforvaltningen i banken. Målingen av risikojustert avkastning gjøres ved hjelp av ulike prestasjonsmål som på hver sine måte reflekterer resultatene av aksjeforvaltningen til sparebanken. Som referanseindeks har vi benyttet Oslo Børs All Share Index (OSEAX) siden banken er eksponert mot de fleste sektorer på Oslo Børs. Resultatet av prestasjonsmålingene viser at sparebanken stort sett ikke har klart å slå markedet. OSEAX leverer for de fleste periodene bedre risikojustert avkastning enn sparebanken