Man has always been fascinated by the flight of birds and insects. First attempts at flight involved flapping wings to mimic the birds and insects that had been observed in flight. Fixed wings proved to be a more practical approach and have been used for over 100 years for manned flight. Emphasis has been placed on flapping wing designs for micro air vehicles (MAVs) as research has shown that challenges arise in lift generation and stability in fixed wing flight as the scale decreases [1].This research explores the use of 3D, time-resolved, Synthetic Aperture PIV (SAPIV) in measuring flow velocities on the mechanical flapping wing of a MAV in tethered flight. The vortical structures on the MAV are measured using both SAPIV and 2DPIV to be able to analyze 2D and 3D velocity fields. The 3D vorticity plots and 2D slice vorticity plots show the three-dimensional nature of the Leading Edge Vortex (LEV) and Trailing Edge Vortex (TEV). 2DPIV plots and 2D slices from the 3D data show general agreement in the structure and behavior of the flow around the flapping wing. The lift and thrust generated by the MAV are measured using a force gauge. The wing tip is tracked in 2D and 3D for synchronization of the measured lift forces with the flow field measurements from the SAPIV. The positive and negative circulation are plotted against the measured lift and thrust forces. The measured lift and thrust forces from the force gauge are then compared to the calculated lift and thrust forces from the measured 3D circulation found through the SAPIV flow field measurements. A plane measured parallel to the LEV and TEV vortex cores allows the defining of a unit vector that is directed normal to the top of the wing and the LEV and TEV cores. The decomposition of the unit vector allows for the calculation of the lift and thrust generated by the circulation around the wing. The comparisons between the measured and calculated forces show good agreement in the case of the measured and calculated lift forces.

Summary  In the 1990s a new way of thinking about forestry started. One of the effects of the changing silvicultural practices was that the size of clearcuts became smaller. As the felling areas were reduced in size, the areas where young and older forest meet grew, with this also the occurrence of edge zones increased. An edge can be defined as an interface between different ecosystems, and a forest edge as an interface between forested and non-forested ecosystems, or between two forests of contrasting composition or structure. This edge results in a transition zone in which the adjacent contrasting ecosystems interact - the edge zone. In the edge zone - both abiotic and biotic - processes result in a detectable difference in composition, structure or function of the vegetation near the edge, as compared with the ecosystem on either side of the edge.  This study aimed to increase understanding of occurrence and types of edge zones and their composition on a property, their effect on tree growth, the species diversity of tree and field vegetation. The study was performed on a property of approximately 60 hectares located in southeastern Blekinge. The sampling procedure was based on four transects ranging from 527 to 860 meters in length, which were laid out in south-north direction over the property. Wherever the transect crossed a forest edge, a corridor perpendicular to the edge was laid out. In each corridor a measuring grid dividing the corridor in 10 distance classes of one meter, measured from the forest edge, was laid out. In each distance class tree species were determined, stems counted, and the following variables were measured per tree: height, distance from edge and the diameter at breast height. Data gathering on forest field vegetation was conducted in 1x1 meter plots laid out in the middle of the corridor. Within each sample area, the occurrence of species was noted according to field vegetation type index. For comparing the edge zones to the rest of the estate, reference plots were laid out along the transects between the forest edges. On the property of 60 hectares an estimated 4,2 hectares were influenced by edge effects. All edges were created by anthropogenic processes, there were forest edges with roads and edges created by forestry. Where thinning stands were bordering roads, growth was found to decrease closer to the road. In pre-commercial thinning stands bordering a road the opposite effect was visible. Where old and young productive forest stands bordered, on the young side there was an increase of both tree height as well as diameter further away from the edge. On the old side no edge effect on tree growth was seen. Herbaceous plants, mosses and lichens were more abundant close to the edge in both old and young stands. Borders with roads had the highest diversity of tree and plant species. The field vegetation was found to be more diverse and abundant closer to the edge. The edge zone showed to be of great importance for natural regeneration. In about half the corridors positive, negative or neutral edge effects were found on one or more of the variables: tree height, diameter, basal area, stems per hectare, plants per hectare. These effects were found up to eight meters into the stand. The inventory of tree species and field vegetation showed that different kinds of edge zones give rise to different species compositions. A higher diversity of tree species was found in the edge zone compared to the reference plots. One could use the edge zone for nature conservation purposes as these areas favor biological diversity and constitute interesting environments for species that would otherwise be at risk of being outcompeted in neighboring, more closed spruce forest stands. Keywords: tree growth, diversity, field vegetation, edge zones, edge effect

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In machining, tool life is the chief determinant of cost, tool changing frequency, machining efficiency, and machining precision. Application of a proper cutting edge with optimized geometry and suitable edge properties is an effective way to improve tool performance and machining quality. The majority of the reported work is limited to the effect of edge geometry on tool life. In this thesis, cutting edges were prepared using three different methods which were evaluated in terms of tool edge geometry produced, tool surface quality and topographies, edge hardness and residual stresses. Furthermore, the influence of cutting edge preparation techniques on the tool performance of uncoated tungsten carbide cutting inserts with different average cutting edge rounding (S¯), different form factor (K), as well as the different edge preparation methods used underwent experimental investigation through the orthogonal turning of AISI 4140 alloy steel. Results show that the performance of the prepared edge depends on the combined effect of micro-geometry and edge properties. For symmetric edges (K=1), the preferable range for S¯ was found to be 20 µm to 30 µm. Drag finishing was determined to be the best edge preparation process which is able to produce cutting edges with the best performance. The experimental investigations provided guidelines and evidence for future study of the cutting tool life and wear behavior of prepared cutting inserts and PVD-coated carbide inserts. / Thesis / Master of Applied Science (MASc)

Event Detection is a process of identifying terrain flatness from which localized events such as potholes in the terrain surface can be found and is an important tool in pavement health monitoring and vehicle performance inspection. Repeated detection of terrain surfaces over an extended period of time can be used by highway engineers for long term road health monitoring. An accurate terrain map can allow maintenance personnel for identifying deterioration in road surface for immediate correction. Additionally, knowledge of the events in terrain surface can be used to predict the performance the vehicles would experience while traveling over it. Event detection is composed of two processes: event edging and stitching edges to events. Edge detection is a process of identifying significant localized changes in the terrain surface. Many edge detection methods have been designed capable of capturing edges in terrain surfaces. Gradient searches are frequently used in image processing to recover useful information from images. The issue with using a gradient search method is that it returns deterministic values resulting in edges which are less precise. In order to predict the precision of the terrain surface, the individual nodal probability densities must be quantified and finally combined for the precision of terrain surface. A Comparative Nodal Uncertainty Method is developed in this work to detect edges based on the probability distribution of the nodal heights within some local neighborhood. Edge stitching is developed to group edges to events in a correct sequence from which an event can be determined finally. / Master of Science

Pyroprocessing is an electrochemical method for recovering actinides from used nuclear fuel and recycling them into fresh nuclear fuel. It is posited herein that proposed safeguards approaches on pyroprocessing for nuclear material control and accountability face several challenges due to the unproven plutonium-curium inseparability argument and the limitations of neutron counters. Thus, the Hybrid K-Edge Densitometer is currently being investigated as an assay tool for the measurement of pyroprocessing materials in order to perform effective safeguards. This work details the development of a computational model created using the Monte Carlo N-Particle code to reproduce HKED assay of samples expected from the pyroprocesses. The model incorporates detailed geometrical dimensions of the Oak Ridge National Laboratory HKED system, realistic detector pulse height spectral responses, optimum computational efficiency, and optimization capabilities. The model has been validated on experimental data representative of samples from traditional reprocessing solutions and then extended to the sample matrices and actinide concentrations of pyroprocessing. Data analysis algorithms were created in order to account for unsimulated spectral characteristics and correct inaccuracies in the simulated results. The realistic assay results obtained with the model have provided insight into the extension of the HKED technique to pyroprocessing safeguards and reduced the calibration and validation efforts in support of that design study. Application of the model has allowed for a detailed determination of the volume of the sample being actively irradiated as well as provided a basis for determining the matrix effects from the pyroprocessing salts on the HKED assay spectra.

Det svenska skogsbruket har med fokus på beståndsvis avverkning och återbeskogning genererat ett mosaikartat landskap med en mängd väl avgränsande kantzoner mellan yngre och äldre bestånd, och att uppkomna förändringar hos växtmiljön i anslutning till dessa beståndsgränser kan påverka såväl tillväxt som artsammansättning har konstaterats i ett flertal tidigare studier. Men även om dessa studier påvisat förekomsten av kanteffekter har resultaten varierat utifrån geografiskt undersökningsområde och studerade trädslag. Tidigare studier har utifrån ett nordiskt perspektiv dessutom främst fokuserat på tillväxtförändringar hos tall i Finland och norra Sverige, vilket föranlett att denna studie valt att undersöka förekomst och omfattning av tillväxteffekter inom kantzoner belägna mellan angränsande äldre och yngre granbestånd i västra Götaland. Studien har genomförts genom att inom ett antal representativa objekt samla in data utifrån utlagda provyor i terrängen och undersökningen har avgränsats till att omfatta trädens höjd- och diametertillväxt samt markvegetationens artsammansättning. Vidare jämförelser har därefter gjorts utifrån avstånd från aktuell beståndsgräns, kantzonernas väderstreck i nordlig respektive sydlig riktning samt de yngre beståndens skötselhistorik i form av röjt eller oröjt. För att undersöka förekomsten av signifikanta skillnader mellan grupperna har insamlad data analyserats med hjälp av variansanalys (ANOVA) samt Tukey’s test för skillnader mellan medelvärden. Resultatet visade på signifikanta kanteffekter hos yngre granbestånd där tillväxtnedsättningarna var som tydligast närmast beståndsgränsen, oavsett väderstreck och tidigare skötselhistorik. Dessa tillväxtnedsättningar var dock mindre än de som tidigare konstaterats hos tall, och till skillnad från tidigare studier kunde inga tillväxteffekter konstateras hos angränsande äldre bestånd. Inga tydliga skillnader kunde heller konstateras utifrån kantzonernas väderstreck eller de yngre beståndens skötselhistorik. Markvegetationens artsammansättning uppvisade i sin tur en ökad förekomst av lavar och bärris intill beståndsgränserna. Bärris, lavar och ljung förekommer frekvent inom sydligt exponerade kantzoner medan smal- och bredbladigt gräs i sin tur uppvisade en ökad förekomst inom nordligt exponerade kantzoner. Utifrån dessa resultat skulle en tänkbar rekommendation inför kommande skogsbruksåtgärder och återbeskogning kunna vara att utifrån konstaterade tillväxtnedsättningar ej prioritera plantering av gran inom ett avstånd av 0-2,5 m från beståndsgräns angränsande mot äldre granbestånd. Därmed skulle kantzonen kunna nyttjas för naturvårdande ändamål då dessa områden gynnar den biologiska mångfalden och utgör intressanta miljöer för arter som annars skulle riskera att bli utkonkurrerade i angränsande mer slutna granskogsbestånd. / The aim of this study was to evaluate edge effects along forest edges between young and old Norway spruce stands in south-western Sweden, and examine its influence on tree growth and field vegetation. Comparison between distance from stand edge, exposure (north or south facing) and young forest clearing (cleared or not cleared) showed a reduced growth among young trees near the stand edge, mainly at a distance of 0-2,5 m. This edge effect occurred regardless of exposure or forest clearing history. On the other hand, in contrary to earlier studies, no positive growth effect was found in older stands adjacent to younger stands. Regarding edge effects found on field vegetation, blueberries, lingonberries and lichens showed an increased incidence adjacent to stand edges. Berries, lichens and heather showed an increased incidence at south facing edges while grass showed an increased incidence at north facing edges.

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A brokerless edge service marketplace could play a significant role in enabling an eco- system where a large number of edge providers and Communication Service Providers (CSPs) offer Mobile Edge Infrastructure Services (EISs) to providers of edge-based applications and services. The marketplace would be the bridge between EIS providers and their customers, managing the relations between actors in the mobile edge eco- system. One of the key services of the marketplace is service selection where not only a list of EISs matching the customers’ demands is provided but also enables service selection based on the customers’ requirements to fully automate the process.We firstly consider different selection scenarios and investigate essential parameters for service selection in such a marketplace, including (i) important attributes of EISs such as coverage area, latency, pricing, etc, and (ii) the requirements of edge-based applications such as latency and reliability. We formulate how these application requirements can be fulfilled by choosing the right set of EISs among available services in the marketplace as two different optimization problems considering average latency and cost as separate objectives to minimize. First, we relax the objective function in average delay minimization problem, which is a linear-fractional programming problem. We solve the relaxed version of the problem by Branch and bound (BnB) and Bound and Branch with Priority Queue (BnBPQ) algorithms. Additionally, we relax the objective function in total monetary cost minimization problem which is an integer linear programming problem. We propose Best Fit (BF) and Improved Best Fit (IBF) algorithms to solve the problem. Furthermore, the IBM CPLEX Optimizer [1] is also implemented to solve the two problems. The evaluation shows that the algorithms we implemented can solve the problems with results close to optimal as compared to the results of exhaustive search and shorter run time than exhaustive search. Meanwhile, the CPLEX can solve the problem well, but it’s not scalable for huge problem instances since the problems are NP-complete and not solvable in polynomial time. / En marknadslös marknadsföring på kanten av tjänster kan spela en viktig roll för att möjliggöra ett ekosystem där ett stort antal kantleverantörer och acp CSP erbjuder Mobile acp EIS till leverantörer av kantbaserade applikationer och tjänster. Marknadsplatsen skulle vara bron mellan ac EIS leverantörer och deras kunder och hantera relationerna mellan aktörer i det mobila ekosystemet. En av marknadens viktigaste tjänster är val av tjänster där inte bara en lista över acp EIS som matchar kundernas krav tillhandahålls utan också möjliggör serviceval baserat på kundernas krav för att automatisera processen helt.Vi överväger för det första olika urvalsscenarier och undersöker väsentliga parametrar för val av tjänster på en sådan marknadsplats, inklusive (i) viktiga attribut för acp EIS som täckningsområde, latens, prissättning osv. Och (ii) kraven på kant- baserade applikationer som latens och tillförlitlighet. Vi formulerar hur dessa applikationskrav kan uppfyllas genom att välja rätt uppsättning acp EIS bland tillgängliga tjänster på marknaden som två olika optimeringsproblem med tanke på genomsnittlig latens och kostnad som separata mål för att minimera. Först slappnar vi av objektivfunktionen i ett genomsnittligt förseningsminimeringsproblem, vilket är ett linjärt-fraktionellt programmeringsproblem. Vi löser den avslappnade versionen av problemet med ac BnB och ac BnBPQ algoritmer. Dessutom slappnar vi av objektivfunktionen i totala monetära kostnadsminimeringsproblem som är ett heltal linjärt programmeringsproblem. Vi föreslår ac BF och ac IBF algoritmer för att lösa problemet. Dessutom implementeras IBM CPLEX Optimizer cite cplex för att lösa de två problemen. Utvärderingen visar att algoritmerna vi implementerade kan lösa problemen med resultat som är nära optimala jämfört med resultaten av uttömmande sökning och kortare körtid än uttömmande sökning. Under tiden kan CPLEX lösa problemet väl, men det är inte skalbart för stora problemstillfällen eftersom problemen är NP-kompletta och inte lösbara under polynom tid.