Conventional drill and blast tunnelling consists of mainly seven elements which together makes a cycle. This cycle includes drilling and blasting which are crucial factors in tunnelling projects, as these have a major influence on how the project will progress. After blasting there can be occurrences of under-break with so called bootholes in it and a re-blast is needed. This is expensive and time-consuming, and is therefore indefensible due to causing extra costs as well as a delay in the completion of the whole project. A solution for this problem is needed to avoid blasting second times. Due to laws regulating the allowed fracture zone in tunnel-blasting, contour blasting is performed. The reason behind why bootlegs emerges after blasting is still unknown and depends on many varied factors, such as geology, blast pattern and the volume of explosives used. Different tests are done while blasting, thereafter the results are evaluated and documented. Each test was tried three times to get as a most reliable result as possible. Among others the amount of explosives ranged, double detonators in poor rock sections and a new drill plan was made. The main theory behind this project was that the problem with bootlegs mainly depended om poor geological situations in the rock. None of the test however have been successful enough to solve the problem and after almost every blast there where bootholes in the remaining rock. Recommendations for further testing are using a less amount of explosives as this was a successful method in Björkdalsgruvan in northern Sweden. Another thing worth giving a try is to remove the “helping-row” because it seems like it is breaking the contour-row and not doing any difference.

Boat-towed high-frequency, short source and receiver spacing, reflection seismic data, 16 profiles and in total 3884 m long, were acquired in 2008 for the planning of the Stockholm Bypass multilane (3 lanes in each direction in two different tubes) underground motorway tunnel designed to ease the ever increasing car traffic on the city and neighbouring regions. The planned bypass will be about 21 km long of which 18 km will be in the form of bedrock tunnel. The planned tunnel will intersect three water passages at where the tunnel will be at around 40-50 m depth. In this study, the seismic data along two of three water passages have been processed and interpreted. Due to the relatively shallow water depth (< 10 m), the main challenge for the reflection data processing was the interferences of strong multiples from lake sediments and bedrock. After a number of tests, it was found that conventional processing methods could not attenuate multiples effectively. Therefore, an optimized workflow based on predictive deconvolution de-multiple method was developed. The new workflow proved to be effective at suppressing multiple reflections, while primary reflections as well as diffraction signals could be well preserved. After carefully attenuating the multiples in the pre-stack and post-stack domains, processing continued with time-to-depth conversion for data interpretations. To reduce uncertainty with time-to-depth conversion errors, bathymetry data available from the study area were used to match the water-sediment interface that also generated a clear reflection in the data. Bedrock surface shows strong undulations, which is typical for the Scandinavian geology from steep valleys to sometimes sub-horizontal at some parts of the water passages. Nevertheless, a dominant bedrock valley-type direction can be recognized striking in the same direction as the water passages. The planned tunnel at the nearest point is estimated to locate approximately 19 m below bedrock surface, which is important factor for the excavation planning of the tunnel and its reinforcements. The steep valley-shaped bedrock may also imply a zone of weakness, fault and/or fracture zone, where the water passages were formed and the reflection seismic data clearly depict this shape under the overlying saucer-shaped unconsolidated sediments.

Introduction: Carpal tunnel syndrome (CTS) is the most common peripheral nerve entrapment seen within the outpatient orthopaedic clinic; therefore assessment and management of this common condition is of significant importance. Traditionally diagnosis has been made through detailed questioning; clinical examination and nerve conduction studies (NCS). There is however no true consensus as to the gold standard assessment of CTS and the use of NCS can confer additional costs and delay treatment. Previous studies have explored methods of predicting the presence of CTS including the clinician-administered Carpal Tunnel Questionnaire (CTQ) (Kamath and Stothard, 2003). The aim of the present studies is therefore to explore the versatility of the CTQ to see how a novel Patient-completed Version of the CTQ compares to the original Clinican-completed version. Psychometric properties of the questionnaire will be explored together the economic impact of integrating both versions within an orthopaedic care pathway. A further aim is to answer whether the CTQ more effective and cost-effective than NCS for patients referred to an orthopaedic clinic with suspected CTS. Method: 100 patients referred for further investigation of suspected CTS were assessed using parallel patient and clinician-completed versions of the CTQ and results were subsequently compared with those obtained from NCS. Item analysis explored each of the nine constructs of the questionnaire and the original scoring algorithm was validated using binary logistic regression and compared with alternative algorithms. Sensitivity and specificity of the questionnaire when compared to results of NCS was explored using Receiver Operating Characteristic (ROC) analyses. Inter-rater reliability was explored through Pearson’s correlation coefficient. Economic analysis and modelling was carried out to explore potential cost savings of use of the questionnaire rather than NCS for those with suspected CTS. Results demonstrated sensitivity of 92% and specificity of 54.67% (positive predictive value 95.35%) for the patient-completed questionnaire and 96% sensitivity with 70.67% specificity (98.15 positive predictive value) for the clinician-completed questionnaire when used to predict the outcome of NCS. Binary logistic regression confirmed the original scoring algorithm and a revised algorithm did not significantly improve sensitivity. Adoption of the clinician-completed CTQ would have screen out 54% of referrals for NCS, which in the case of the study site would have conferred cost savings of £73,305 per annum (base upon a referral rate of 750 per annum). The patient-completed CTQ in the current sample resulted in 43% of referrals with suspected CTS not requiring NCS to assist in diagnosis with a potential saving of £58,372.5 per annum. There are further considerations of the reduction in waiting times, which are explored further within the analysis. Conclusion: Economic evaluation is complex due to the variety of pathways adopted by different orthopaedic departments. While the results of the Patient-complete version of the CTQ may not be as convincing as the clinician completed the study does provide validation for its use and expands the versatility of this useful adjunct to the assessment of CTS. Both versions could potentially confer significant cost savings and reduce demands on investigative services, reducing waiting times and improving the patient journey in suspected CTS.

For over a decade now there has been much research into the use of superconductors in X-ray, gamma ray and other particle detectors. Detectors based on superconductor-insulator-superconductor(SIS) and superconductor-insulator-normal metal(SIN) tunnel junctions have been widely developed. To date, the predicted excellent energy resolving ability of such detectors has not been realised. Various energy loss processes have been suggested as possible causes for the failure to obtain energy resolutions close to the thermodynamic and quantum limits predicted. In my experiments, I have used both SIS and SIN tunnel junctions to investigate the transport of quasiparticles and phonons in structures similar to the proposed detector designs. I have used multiple distributed junction geometries to perform injection-detection type experiments. One junction is used to inject quasiparticles and/or phonons into the device structure, whilst the current-voltage characteristic of a second junction is monitored for a response to the injected quasiparticles/phonons. Using this type of experimental set-up, I have measured the transport of non-thermal equilibrium quasiparticles in an epitaxial niobium film. Using a simple random walk model, I have calculated an effective lifetime for quasiparticles. I have not observed the process of quasiparticle mulitiplication that has been observed by other researchers - I attribute this to differences in the microstructure of my devices and comment on the implications of this to possible quasiparticle loss mechanisms. I have investigated the energy transport in a device with a number of SIN tunnel junctions connected to a common normal metal electrode. Phonon transport via the substrate is found to be the dominant coupling process between the tunnel junctions, although the device design can result in some junctions being effectively shielded from the substrate phonons by the common electrode. Finally, the possibilities of using a superconducting heterostructure to control the rate at which quasiparticles recombine and emit phonons have been explored. Excessive recombination is believed to limit the effectiveness of large areas SIN tunnel junctions as thermometers for particle detecting bolometers.

Le contexte général de ce travail est le développement et l'intégration de nouveaux matériaux magnétiques ayant des propriétés originales et d'intérêt potentiel pour la spintronique. En tant que matériau ferromagnétique d’aimantation nulle, le composé Sm1-xGdxAl2 (SGA) suscite un intérêt particulier, puisqu’il est capable, dans son état magnétique compensé, de polariser en spin un courant d’électrons. Dans un premier temps, des expériences de photoémission résolues en angle et en spin sur synchrotron ont permis d’effectuer une analyse précise de la structure électronique selon diverses directions de la zone de Brillouin et d’estimer de manière directe la polarisation de spin au niveau de Fermi du composé SGA. Dans un second temps, une attention particulière a été portée aux multicouches [Co/Pt] et aux JTMs à base de [Co/Pt]. Les multicouches [Co/Pt] constituent la seconde électrode des JTMs à base de SGA. Leurs propriétés magnétiques (en particulier l'anisotropie perpendiculaire et l'aimantation à saturation) ont été soigneusement étudiées en fonction de l'épaisseur de Pt et de la nature de la couche tampon (Pt, MgO ou Al2O3), et en liaison avec leurs caractéristiques structurales. Leur intégration dans des JTMs à base de [Co/Pt] a permis ensuite de remonter d’une part à la polarisation tunnel effective des multicouches [Co/Pt] et d’autre part aux configurations magnétiques des différentes électrodes, configurations parfaitement expliquées et reproduites par des simulations micro-magnétiques. Dans un troisième temps, les résultats de magnéto-transport au sein des JTMs SGA/MgO/[Co/Pt] sont présentés et discutés / The general context of this work is the development and integration of new magnetic materials with original properties of potential interest for spintronic applications. In this field, the Sm1-xGdxAl2 (SGA) compound drives a particular attention, as a zero-magnetization ferromagnet that can exhibit a spin polarization in its magnetic compensated state. In a first step, synchrotron-based angle and spin resolved photoemission spectroscopy experiments have permitted to perform an accurate analysis of the electronic structure along various directions of the Brillouin Zone and to get a direct estimation of the spin polarization at the Fermi level. In a second step, a special attention has been the paid to [Co/Pt] multilayers and to [Co/Pt]-based MTJs. The [Co/Pt] multilayers would constitute the second electrode in SGA-based MTJs. Their magnetic properties (especially the perpendicular anisotropy and the saturation magnetization) have been carefully investigated as a function of Pt thickness and nature of the buffer layer (Pt, MgO or Al2O3), and in close connection with structural characteristics. Their integration in [Co/Pt]-based MTJs has permitted to determine the [Co/Pt] effective tunnel polarization and to unravel the magnetic configurations of both electrodes which are perfectly explained and reproduced by micromagnetic simulations. In a third step, the results concerning the magneto-transport experiments in SGA/MgO/[Co/Pt] MTJs are presented and discussed

La découverte du graphène a récemment ouvert de nouvelles opportunités en termes de fonctionnalités et de performances pour les dispositifs de spintronique. Ce travail comporte deux études sur l’utilisation du graphène en spintronique.C’est en premier lieu pour ses propriétés de transport de spin que le graphène a suscité un fort intérêt en spintronique. En effet, de par sa forte mobilité et son faible couplage spin-orbite, il est rapidement apparu comme ayant un fort potentiel pour le transport de l’information de spin avec des longueurs de diffusion de spin attendues de l’ordre de la centaine de microns.Dans une première étude, je m'intéresse au graphène en tant que plateforme pour propager un courant polarisé en spin. Je décris tout d'abord les principales techniques de mesure de vannes de spin latérales, en insistant sur l'importance de la barrière tunnel pour se placer dans les conditions appropriées à la mesure des propriétés intrinsèques au graphène. Je présente ensuite les résultats que j’ai obtenus. Je commence par ceux sur graphène épitaxié sur SiC dans lequel nous avons réussi à injecter, propager et détecter un courant polarisé en spin créé soit grâce à un injecteur ferromagnétique (Co/Al2O3), soit par effet Hall de spin (à partir du platine). Je présente ensuite les résultats obtenus sur un autre type de graphène grande surface, le graphène CVD monocouche, pour lequel j'ai pu expérimenter une nouvelle barrière tunnel: le nitrure de bore hexagonal.Par-delà ses propriétés de transport latéral, le graphène pourrait avoir un autre intérêt pour la spintronique, par exemple dans le cadre de la passivation des couches ferromagnétiques dans les jonctions tunnel magnétiques.Dans une seconde étude, je m'intéresse au graphène comme membrane pour protéger une électrode ferromagnétique de l'oxydation tout en autorisant l’extraction d’un courant polarisé en spin. Aujourd’hui, dû à la propension naturelle des matériaux ferromagnétiques à s’oxyder, les procédés humides/oxydants sont souvent exclus de la fabrication de dispositifs de spintronique. Après avoir introduit les enjeux, je présente mes résultats expérimentaux. Je montre tout d'abord qu’une monocouche de graphène suffit à empêcher l'oxydation d'une électrode de nickel et qu’un filtrage de spin intéressant apparaît à l'interface Ni/Graphène. Je valide ensuite l'ensemble de ce potentiel en montrant qu'on peut utiliser une technique oxydative de dépôt tel que l'Atomic Layer Deposition (ALD) sans endommager les propriétés de l'électrode ferromagnétique Ni+Graphène. Le procédé d’ALD, bien qu'utilisé partout en électronique (cette technique sert aujourd’hui à réaliser les grilles des transistors d’Intel), était jusqu’ici proscrit car il met en jeu des molécules telles que l'ozone ou l'eau et est donc par nature oxydant. Enfin, je montre que le filtrage de spin à l’interface Ni/Graphène aboutit alors à une inversion quasi-totale de la polarisation en spin du Ni.Ce travail de thèse montre que le graphène peut être utilisé comme canal de transport d’un courant polarisé en spin, comme membrane protectrice imperméable à l’oxydation ou encore comme filtre à spin. L’ensemble de ces travaux illustre la richesse des applications du graphène pour la spintronique. / Graphene discovery has opened new opportunities in terms of functionality and performance for spintronics devices. This work presents two examples of what graphene can bring to the spintronics field.Graphene first aroused interest amongst the community because of its excellent properties for transporting spin information. Indeed, thanks to its high reported mobilities and its weak spin-orbit coupling, graphene quickly became a high-potential candidate to transport spin information with expected spin diffusion length in the hundreds of microns range.In the first part of this thesis, I study graphene as a platform to propagate a spin polarized current. I first describe the main techniques to measure lateral spin valves, emphasizing the importance of the tunnel barrier being under the right conditions to permit measurement of the intrinsic properties of graphene. I then present my results. I begin with the results obtained on epitaxial graphene on SiC, in which I was able to inject, propagate and detect a spin current created either by a ferromagnetic injector (Co/Al2O3), or through the spin Hall effect (from Pt). Then, I present the results obtained on another large-area graphene, a single layer of graphene grown by CVD on which I tested a new unnel barrier : hexagonal boron-nitrideBeyond its potential as a platform to transport spin information, other opportunities for graphene in spintronics exist, for example its use in the passivation of ferromagnetic layers in magnetic tunnel junctions.In the second part of this thesis, I am interested in graphene’s potential as a membrane that could protect ferromagnets from oxidation while simultaneously allowing the extraction of a spin current. Indeed, because of the natural propensity of the ferromagnetic material to be oxidized, humid and oxidative processes are excluded from the fabrication of spintronic devices. After introducing the background motivation, I present my experimental results. I first show that a single layer of grapheneis enough to prevent the oxidation of a Ni electrode and that an interesting spin filtering effect happens at the interface Ni/Graphene. I then confirm this by showing that it is possible to use an oxidative technique like Atomic Layer Deposition (ALD) without damaging the properties of the ferromagnetic electrode Ni+Graphene. ALD is widely used in electronics (Intel uses it to make its transistor gates) but was up to now prohibited in spintronics because it involves oxidative molecules like water or ozone. Finally, I show that the spin-filtering effect at the interface Ni/Graphene leads to a quasi-total reversal of the spin polarisation of the Ni.This thesis shows that graphene can be used as a channel to transport spin information, as a protective membrane to protect against oxidation, or as a spin filter. All this work illustrates the richness of graphene applications for spintronics.

Knot theory and 3-manifold topology are closely intertwined, and few invariants stand so firmly in the intersection of these two subjects as the tunnel number of a knot, denoted t(K). We describe two very general constructions that result in knot and link pairs which are subbaditive with respect to tunnel number under connect sum. Our constructions encompass all previously known examples and introduce many new ones. As an application we describe a class of knots K in the 3-sphere such that, for every manifold M obtained from an integral Dehn filling of E(K), g(E(K))>g(M).

Magnetic sensors are deployed in many applications such as automotive, consumer electronics, navigation and data storage devices. Their market’s growth is driven by demands of higher performance; primarily to assist in the advancement of the Internet of Things (IoT) and smart systems. Challenging obstacles of miniaturization and power consumptions must be overcome. A leading sensor that has the potential to accelerate the development is the magnetic tunnel junction (MTJ) devices. Corrosion causes catastrophic consequences for industries. Preventive measures could save up to 35% of annual corrosion-related costs. An advanced corrosion sensing technique is developed based on iron nanowires. The iron nanowires are magnets which lose their magnetization when corroded. Their magnetization loss is monitored using sensitive MTJ sensor. Combined, the nanowires and the MTJ sensor realize a highly integrated sensor concept that enables corrosion sensing with an ultra-low power consumption of less than 1 nW, a sensitivity of 0.1 %/min, a response time of 30 minutes and an area of 128 μm2. Surgical tool development is accelerating in the healthcare sector. Cardiac catheterization specifically is a minimally invasive surgery that relies heavily on x-ray imaging and contrast dyes. A flexible tri-axis MTJ sensor is developed to help minimizing the need for x-ray imaging during the procedure. The flexible sensor can bend to a diameter of 500 μm without compromising the performance and can endure over 1000 bending cycles without fatigue. Three flexible sensors are mounted onto the tip of a 3 mm cardiac catheter, realizing a novel sensor-on-tube (SOT) tri-axis sensor concept. The sensor has a high sensitivity of 9 Ω/° and an MR ratio of 29%. It weighs 16 μg only, adds 5 μm to the catheter’s diameter and a total size 300 μm2. The prototype system estimated the heading angle with an RMS error value of 7° and tracked the orientation of the sensor with an acceptable accuracy. However, the sensor has a misalignment issue caused by the manual placement of the sensors. A high precision tool is needed for the assembly, and any further misplacement -within a reasonable margin of error- could be corrected by calibration algorithms.

This thesis focuses on problem with detection of cavitation in hydraulic systems and devices. Thesis works with data from cavitation tunnel experiment, where cavitation appeared on blade. It founds out if time records and their frequency spectrum is dependent on operating conditions. Data are examined by various statistic methods. All of that is then used in method called neural network.

The demand for local sustainably grown produce and flowers has increased (Low et al., 2015), and stimulated a growing interest in high tunnel production. The goal of this research project was to evaluate the production of cut flowers in high tunnel structures and in the field in the Northern Great Plains (NGP) region. The NGP offers unique climatic and environmental challenges based on its continental climate. Specialty cut flower cultivars Karma Irene and Chocolate dahlia (Dahlia x hybrida), Potomac White and Rocket Mix snapdragon (Antirrhinum majus), and Mariachi Misty Blue, Echo Blue and ABC2 lisianthus (Eustoma grandiflorum) were planted in both field and high tunnel environments at two soil temperature setpoints in the NGP to determine which of the selected crops are best suited for cut flower production. Our results indicate higher yields and more consistent quality in the high tunnel; however, the field was suitable for all species investigated.