Generation, Renderingand Animation of Polygon Tree Models

This thesis contains a set of contributions that focuses on challenges in visualization of polygon models of trees, in particular models of tree stems and branches. These challenges cover a wide range of the visualization research field, including generation of polygon models of trees, hardware accelerated visualization and animation of trees from parametric systems, and surface modelling and tessellation for tree stems. To generate polygon models of trees, an existing approach for automatically generating polygon models of branching vascular transportation systems, typically blood vessels, is extended to handle tree stems. The approach allowed for automation of the generation process, while maintaining smoothness at branching areas. The approach is used to generate polygon models of trees. For hardware accelerated visualization and animation of trees from parametric systems, methods for visualization of trees described by parametric descriptions are adapted and extended to run on dedicated graphic processing hardware. To allow for animation of trees visualized in such a manner, an animation process that is hardware accelerated is developed using knowledge gained from work on hardware acceleration approaches in the field of image processing. For surface modelling and tessellation for visualization of trees, concepts, ideas and early work are presented. The basic concept is that by working with a coarse polygon model of a tree during animation (or by generating a coarse polygon model of a tree after animation is done); one can tessellate this coarse model in hardware in real-time to a much higher degree then earlier approaches. This will then enable one to visualize trees stems of a higher Level of Detail (LOD) and at higher speeds than were previously achievable. Although the contributions in this thesis cover a wide range of challenges from the visualization research field, the main focus has been on generation, animation and visualization of tree stems and branches for use in real-time applications. Especially the concept of hardware acceleration has become more of a focus, as graphic processing hardware has become more and more powerful both in speed and especially in functionality. The contributions will hopefully help in future development of even better methods for visualizing trees and plants.PhD i informasjons- og kommunikasjonsteknologiPhD in Information and Communications Technolog

En sammenligning av to arkivdepotinstitusjoner IKA Trøndelag og Statsarkivet i Trondheim

Denne oppgaven tar for seg likheter og forskjeller i to forskjellige arkivdepotinstitusjoner. Problemstillingen som blir undersøkt er: Med hensyn til konkrete arbeidsoppgaver, hvilke likheter og forskjeller er det i arbeidet de gjør på arkivdepotinstitusjonene IKA Trøndelag og Statsarkivet i Trondheim? Det er en sammenligning mellom deres arbeidsoppgaver og rutiner, og programmer og systemer de bruker i depotet. Dette var noe som interesserte meg, og jeg ville få mer innsikt og lære mer om det de gjør til daglig på arkivdepot. Det ble gjennomført intervju, og fikk gode svar tilbake. Gjennom å utføre en empirisk studie av kvalitativ karakter, har det altså blitt sammenlignet to ulike arkivdepotinstitusjoner, og det ble funnet ut at både likhetene og forskjellene stikker seg ut. Institusjonene er arkivdepotinstitusjoner og arbeider med å ta vare på arkivmateriale, men de arbeider på ulikt vis innen de mange arbeidsoppgavene. I denne besvarelsen blir det også forklart hvordan de forskjellige arbeidsoppgavene blir utført. Jeg har ikke funnet noe som tilsier at det er forsket på dette tidligere. Det er en del statistikk, men ingenting om selve arbeidsoppgaver og sammenligninger

Identifisering og karakterisering av bakteriocinet amylocyclicin fra Bacillus velezensis, og dets potensial mot Listeria monocytogenes

Stadig flere bakterier blir resistente mot antibiotika som brukes for å behandle bakterielle infeksjoner. Verdens helseorganisasjon har erklært antimikrobiell resistens som et av verdens største globale helseutfordringer som menneskeheten står ovenfor. For å kunne løse problemet er det avgjørende å finne alternativer til dagens bruk av antibiotika. En del av løsningen kan være å benytte bakteriers egenproduserte antimikrobielle peptider, også kalt bakteriociner. Bakteriociner er små ribosomalt syntetiserte peptider med stor variasjon i både struktur, aktivitet og målorganismer. Bakteriociner produseres av en rekke ulike bakterier, og syntesen av bakteriociner krever som regel minst to ekstra gener som koder for dedikerte transport- og immunitetsproteiner. Immunitet gjør at produsenten ikke blir hemmet av sitt eget bakteriocin, og på den måten utnyttes bakteriociner i konkurranse om næring og nisjer. Målet for denne oppgaven var å identifisere og karakterisere et antimikrobielt stoff produsert av en Bacillus velezensis stamme. Ved bruk av helgenomsekvensering, revers-fase kromatografi og massespektrometri ble dette stoffet identifisert til å være det sirkulære bakteriocinet amylocyclicin. Amylocyclicin var allerede beskrevet, men det var mye som ikke var kjent om peptidets antimikrobielle aktivitet, virkemåte og immunitet. Dette bakteriocinet ble derfor undersøkt videre. Amylocyclicin viste seg å være et poredannende bakteriocin med høy stabilitet mot varme- og pH-forandringer, og hadde et bredt inhiberingsspekter mot nesten alle Gram-positive bakterier. Det ble observert spesielt god aktivitet mot den patogene bakterien Listeria monocytogenes, en robust bakterie som kan forårsake den alvorlige sykdommen listeriose. L. monocytogenes kan også danne biofilm, som er et problem i mat- og helseindustrien. Flere ulike matprodukter, som røkt laks, har tidligere vært smittekilde for denne bakterien. Amylocyclicin var effektiv mot biofilm produsert av L. monocytogenes, og konfokal mikroskopi viste at bakteriocinet reduserte både celletettheten og levende celler i biofilmen. I tillegg var amylocyclicin effektiv som preventiv behandling for å hemme vekst av L. monocytogenes inokulert på røkt laks. Denne oppgaven viser at amylocyclicin har flere egenskaper som gjør at det kan være egnet for videre utvikling til bruk i mat- og helseindustrien. Videre forskning anbefales derfor på amylocyclicin og bakteriociner generelt, spesielt med hensyn til deres virkemåte og toksisitet, før de eventuelt kan utnyttes i kampen mot antibiotikaresistens.An increasingly number of bacteria are becoming resistant to antibiotics commonly used to treat infections. The World Health Organization has declared antimicrobial resistance as one of the greatest public threats facing humanity. To solve this problem, it is crucial to find alternatives to how antibiotics are presently used. A part of the solution could be the use of the antimicrobial peptides produced by the bacteria themselves, molecules also known as bacteriocins. Bacteriocins are small ribosomally synthesized peptides that vary considerably in structures, activity, and target organisms. Bacteriocins are produced by many different bacteria, and their biosynthesis most often requires two extra genes encoding dedicated transport and immunity proteins. Immunity enables the producing organisms to inhibit other bacteria in competition for nutrients and niches. The aim of this thesis was to identify and characterize an antimicrobial substance produced by a Bacillus velezensis strains. By the use of whole-genome sequencing, reversed-phase chromatography and mass spectrometry, the antimicrobial substance was identified as the circular bacteriocin amylocyclicin. Amylocyclicin have been previously described, but little is known about its antimicrobial activity, mode of action, and immunity. Amylocyclicin was shown to have a mode of action involving pore-formation and to have high thermal and pH-stability. Additionally, amylocyclicin exhibited broad-spectrum activity towards most Gram-positive bacteria. The activity was particularly potent against Listeria monocytogenes, a robust pathogen that causes the serious illness listeriosis. L. monocytogenes is also a strong biofilm producer, which is a problem in the food and health industry. Several ready-to-eat food products, such as smoked salmon, have been the source of numerous listeriosis outbreaks. Amylocyclicin was effective at disrupting biofilms produced by L. monocytogenes, and confocal microscopy revealed that the amylocyclicin treatment reduced the cell density and living cells in the biofilm. Additionally, pre-treatment of smoked salmon with amylocyclicin was shown to effectively inhibit the growth of L. monocytogenes. This thesis demonstrates that amylocyclicin has potential for applied use in the food and health industry. Further research on amylocyclicin and bacteriocins in general is thus needed, particularly regarding their mode of action and toxicity, prior to their effective use as a supplement or alternative to antibiotics

Dietary b-glucan (MacroGard®) enhances survival of first feeding turbot (Scophthalmus maximus) larvae by altering immunity, metabolism and microbiota

Reflecting the natural biology of mass spawning fish aquaculture production of fish larvae is often hampered by high and unpredictable mortality rates. The present study aimed to enhance larval performance and immunity via the oral administration of an immunomodulator, β-glucan (MacroGard®) in turbot (Scophthalmus maximus). Rotifers (Brachionus plicatilis) were incubated with or without yeast β-1,3/1,6-glucan in form of MacroGard® at a concentration of 0.5 g/L. Rotifers were fed to first feeding turbot larvae once a day. From day 13 dph onwards all tanks were additionally fed untreated Artemia sp. nauplii (1 nauplius ml/L). Daily mortality was monitored and larvae were sampled at 11 and 24 dph for expression of 30 genes, microbiota analysis, trypsin activity and size measurements. Along with the feeding of β-glucan daily mortality was significantly reduced by ca. 15% and an alteration of the larval microbiota was observed. At 11 dph gene expression of trypsin and chymotrypsin was elevated in the MacroGard® fed fish, which resulted in heightened tryptic enzyme activity. No effect on genes encoding antioxidative proteins was observed, whilst the immune response was clearly modulated by β-glucan. At 11 dph complement component c3 was elevated whilst cytokines, antimicrobial peptides, toll like receptor 3 and heat shock protein 70 were not affected. At the later time point (24 dph) an anti-inflammatory effect in form of a down-regulation of hsp 70, tnf-α and il-1β was observed. We conclude that the administration of MacroGard® induced an immunomodulatory response and could be used as an effective measure to increase survival in rearing of turbot

Towards a Simple Augmented Reality Museum Guide

Modelling knowledge for agents and virtual entities can be hard. Often the domain knowledge needed increases as the complexity of the agent increases. What is worse is that for increasingly complex agents the needed knowledge of the underlying reasoning methods may also increase for the domain experts. In light of this we present early work and thoughts on a virtual museum guide system that should be easy to configure and maintain by domain experts.This is the authors' accepted and refereed manuscript to the article

Evaluation of Road Safety Education Program with Virtual Reality Eye Tracking

Traffic rules are essential and part of today’s road safety education programs at school. However, learning how to properly use attention in complex traffic situations has never before been a focus when teaching pupils. A new road safety education program based on latest findings in Neuro-Education has been developed. In the program, pupil learned three new concepts: risk, orientation and attention. This to stimulate the pupil’s reflection about own behavior on school roads, before attended a session at a traffic center, where teachers encouraged pupil’s reflection about how to practically use their new knowledge about the three concepts. This new program design was evaluated in a Virtual Reality laboratory. This paper presents the approach for evaluation using VR and eye-tracking, including scenario building, measurement approach, and procedure for measurements in addition to a look at the actual evaluation results. The results showed that pupils managed to cycle in a safer way by putting their attention at the right places after the course compared to student following existing curriculum. As such the selected validation approach utilizing VR gave clear support for the proposed education program.publishedVersio

Feasibility of Biochar from Seaweed for Ferroalloy Production

Biochar from seaweed, specifcally sugar kelp, cultivated on the Norwegian coastline has been investigated as a possible biocarbon source for the metal industry to reduce the dependency on terrestrial biomass. Pre-processing of the biomass prior to pyrolysis is needed to reduce the water and ash content and was performed by water and acid washing followed by drying. The three types of biochar were obtained after pyrolysis at a temperature of 550 °C. Characterization of the three batches of biochars showed that pre-processing of the seaweed as was done during the water and acid washing, plays an important role on the removal of ash content. Due to the enormous amount of woody biomass needed for example in the ferroalloy industry to replace fossil coal, replacing only parts of the woody biomass with kelp biochar could have a signifcant impact. Water washing combined with acid washing had the best results considering the ash and fxed carbon contents. Microstructural analysis of the seaweed biochars showed a very porous material with the crystal structure resembling that of charcoal, albeit a lower degree of crystallinity.publishedVersio

Iodine content in bulk biomass of wild-harvested and cultivated edible seaweeds: Inherent variations determine species-specific daily allowable consumption

This study represents a large-scale investigation into iodine contents in three commercially important and edible seaweed species from the North Atlantic: the brown algae Saccharina latissima and Alaria esculenta, and the red alga Palmaria palmata. Variability among and within species were explored in terms of temporal and spatial variations in addition to biomass source. Mean iodine concentration in bulk seaweed biomass was speciesspecific: Saccharina > Alaria > Palmaria. Iodine contents of Saccharina biomass were similar between years and seasons, but varied significantly between sampling locations and biomass sources. In Alaria and Palmaria, none of the independent variables examined contributed significantly to the small variations observed. Our data suggest that all three species are rich sources of iodine, and only 32, 283, or 2149 mg dry weight of unprocessed dry biomass of Saccharina, Alaria, or Palmaria, respectively, meets the recommended daily intake levels for most healthy humans.publishedVersio

Standardized messages in C-ITS - The CAN and DENM standards

This memo summarizes the Cooperative Awareness Message (CAM) and Decentralized Environmental Notification Message (DENM) message format for C-ITS. CAM and DENM are standardized by ETSI in ETSI EN 302 637-2 (v.1.3.2 used here) and ETSI EN 302 637-3 (v.1.2.1 used here) respectively. The memo also describes some of the intended use cases for these message types. The memo focuses on the content of the messages, and does not describe or take into account the network of the data communication other than in an overall view where this is required to explain critical aspects. Parties interested in the network and data communication is referenced to standards such as ETSI EN 302 636-4-1 and ETSI EN 302 636-4-2 (Geo-Networking), ETSI EN 302 636-5-1 (BTP) and ETSI EN 302 636-6-1 (IPv6 over GN) for a starting point. An overview off all the standards that entails the CEN/ISO Release 1 for cooperative ITS can be seen at http://release1.its-standards.eu.Statens vegvesenpublishedVersio

Analysis of visual and acoustic measures for self-evacuations in road tunnels using virtual reality

Emergency fire situations in tunnels can be especially dangerous when occurring in long underground or subsea tunnels, particularly when evacuation on foot is the only alternative. This paper presents the results from a study comparing different visual and acoustic measures to facilitate efficient and safe emergency evacuation and their effect on people's self-rescue behaviour in response to a tunnel fire. Eighty-one participants evaluated seven different scenarios in virtual reality with or without visual and acoustic supporting measures (i.e. signs, lights, acoustic beacons) to find their way to emergency doors. Objective behavioural data, such as orientation, and walking speed, were collected. The results suggest that the distance between the emergency doors increases uncertainty and affects the time to self-rescue significantly, with four times longer times for 500 m than 250 m between doors. Additionally, the use of continuous guiding lights positively supported orientation and walking speed, with 97 % of the participants finding their way and showing a reduction of time to reach the emergency door of 10–20 s. The study underscores the importance in the proper visual and acoustic evacuation measures for the wayfinding of emergency exits, improving self-rescue of people.publishedVersio