High tunnels are used to modify the crop environment by trapping solar energy, providing protection from unfavorable weather events, and extending the growing season in temperate regions. This project assessed yield and quality in three independent cultivar trials of warm-season crops tomato (Solanum lycopersicum L.), bell pepper (Capsicum annuum L.) and cucumber (Cucumis sativus L.) grown under high tunnel production compared with an outdoor field in eastern and western North Dakota. Tomato yields in the high tunnel were increased by 1.4 times over the field trial yields. Yields from the pepper cultivar trials both inside the high tunnel and outside field were comparable to one another at 1.24 kg plant-1 and 1.06 kg plant-1, respectively. Cucumber yields in the high tunnel were increased by 1.7 times over the field trial yields. Results indicate that in North Dakota, high tunnels extended the growing season, and increased production relative to field conditions.

Much research and experiments have gone into studying idealized wing-body junction flows and their impact on horseshoe vortex and wake formation.  The vortices have been found to generate regions of high surface pressure fluctuations and turbulence that are detrimental to structural components and acoustics.  With the focus in the military and commercial industry on reducing the acoustical impact of aircraft and their engines, very little research has been done to examine the potential impact wing-body junctions may have on acoustics, especially for high lifting bodies such as propellers.  Two similar tests were conducted in the Virginia Tech Open Jet Wind Tunnel where boundary layer measurements, oil flow visualizations, acoustic linear array and surface pressure fluctuation measurements of a baseline Rood airfoil model and two novel junction fairing designs were all taken.  Boundary layer measurements were taken at four locations along the front half of the flat plate and the profiles were shown to be all turbulent despite the low Reynolds number of the flow, (test 1: Re_"<1400, test 2: Re_"<550).  Oil flow visualizations were taken and compared to those of previous researchers and the location of separation and line of low shear along with the maximum width of the wake and width of wake at the trailing edge all scaled relatively well with the Momentum Deficit Factor, defined for wing-body junction flows [Fleming, J. L., Simpson, R. L., Cowling, J. E. & Devenport, W. J., 1993. An Experimental Study of a Turbulent Wing-Body Junction and Wake Flow. Experiments in Fluids, Volume 14, pp. 366-378. ].  A linear microphone array was used to estimate the directivity of the facility acoustic background noise to be used to improve background subtraction methods for surface pressure fluctuation measurements.  Surface pressure fluctuation spectra were taken ahead of the leading edge of the plate and along the surface of the models.  These showed that the fairings reduced pressure fluctuations along the plate upstream of the leading edge, with fairing 1 reducing them to clean tunnel flow levels.  On the surface of the models, the fairings tended to reduce low frequency (<1000Hz) pressure fluctuation peaks when compared to the baseline model and increase the pressure fluctuations in the high frequency range.  Simple scaling arguments indicate that this spectral change may be more beneficial than detrimental as low frequency acoustics especially those between 800 Hz and 1200 Hz are the frequencies that humans perceive as the loudest noise levels.  Scaling the frequencies measured to those of full scale applications using Strouhal numbers show that frequencies below 1000 Hz in this experiment result in frequencies at the upper limit of the human hearing frequency range.  Low frequency acoustic waves also tend to travel farther and high frequency acoustic waves are more apt to be absorbed by the surrounding atmosphere. / Master of Science

This project examined the effect of Gurney flaps on a 2D, 2-ft chord NACA 0036 airfoil in the Cal Poly 3’x4’ low speed wind tunnel at 25 m/s. It also covered the numerical simulation of the experiment in computational fluid dynamics (CFD). During the study, problems with the wind tunnel data were seen. After a careful diagnosis, the problem was traced to dirty flow conditioners which were subsequently replaced. Five Gurney flaps at 1, 2, 3, 4, and 5% of the chord were tested. The Gurney flaps had the effect of eliminating the lift reversal effect and lowering the profile drag at low angles of attack, ranging from 4-27%. The optimal Gurney flap appeared to be 2% of the chord. CFD modeling of the problem had limited success, with the best results coming from Mentor’s k-w SST turbulence model. This model reproduced the non-linear lift curve, and captured the trend in rising drag fairly well, but failed to predict the correct point of separation. Attempts to model the Gurney flap in CFD were unsuccessful.

Les mémoires non-volatiles (MNV) sont l'objet d'un effort de recherche croissant du fait de leur capacité à limiter la consommation statique, qui obère habituellement la réduction des dimensions dans la technologie CMOS. Dans ce contexte, cette thèse aborde plus spécifiquement deux technologies de mémoires non volatiles : d'une part les jonctions tunnel ferroélectriques (JTF), dispositif non volatil émergent, et d'autre part les dispositifs à transfert de spin (TS) assisté par effet Hall de spin (EHS), approche alternative proposée récemment pour écrire les jonctions tunnel magnétiques (JTM). Mon objectif est de développer des modèles compacts pour ces deux technologies et d'explorer, par simulation, leur intégration dans les circuits non-volatiles.J'ai d'abord étudié les modèles physiques qui décrivent les comportements électriques des JTF : la résistance tunnel, la dynamique de la commutation ferroélectrique et leur comportement memristif. La précision de ces modèles physiques est validée par leur bonne adéquation avec les résultats expérimentaux. Afin de proposer un modèle compatible avec les simulateurs électriques standards, nous j'ai développé les modèles physiques mentionnés ci-dessus en langue Verilog-A, puis je les ai intégrés ensemble. Le modèle électrique que j'ai conçu peut être exploité sur la plate-forme Cadence (un outil standard pour la simulation de circuit). Il reproduit fidèlement les comportements de JTF. Ensuite, en utilisant ce modèle de JTF et le design-kit CMOS de STMicroelectronics, j'ai conçu et simulé trois types de circuits: i) une mémoire vive (RAM) basée sur les JTF, ii) deux systèmes neuromorphiques basés sur les JTF, l'un qui émule la règle d'apprentissage de la plasticité synaptique basée sur le décalage temporel des impulsions neuronale (STDP), l'autre mettant en œuvre l'apprentissage supervisé de fonctions logiques, iii) un bloc logique booléen basé sur les JTF, y compris la démonstration des fonctions logiques NAND et NOR. L'influence des paramètres de la JTF sur les performances de ces circuits a été analysée par simulation. Finalement, nous avons modélisé la dynamique de renversement de l'aimantation dans les dispositifs à anisotropie perpendiculaire à transfert de spin assisté par effet Hall de spin dans un JTM à trois terminaux. Dans ce schéma, deux courants d'écriture sont appliqués pour générer l'EHS et le TS. La simulation numérique basée sur l'équation de Landau-Lifshitz-Gilbert (LLG) démontre que le délai d'incubation de TS peut être éliminé par un fort EHS, conduisant à la commutation ultra-rapide de l'aimantation, sans pour autant requérir une augmentation excessive du TS. Nous avons appliqué cette nouvelle méthode d'écriture à la conception d'une bascule magnétique et d'un additionneur 1 bit magnétique. Les performances des circuits magnétiques assistés par l'EHS ont été comparés à ceux écrits par transfert de spin, par simulation et par une analyse fondée sur le modèle théorique. / Non-volatile memory (NVM) devices have been attracting intensive research interest since they promise to solve the increasing static power issue caused by CMOS technology scaling. This thesis focuses on two fields related to NVM: the one is the ferroelectric tunnel junction (FTJ), which is a recent emerging NVM device. The other is the spin-Hall-assisted spin-transfer torque (STT), which is a recent proposed write approach for the magnetic tunnel junction (MTJ). Our objective is to develop the compact models for these two technologies and to explore their application in the non-volatile circuits through simulation.First, we investigated physical models describing the electrical behaviors of the FTJ such as tunneling resistance, dynamic ferroelectric switching and memristive response. The accuracy of these physical models is validated by a good agreement with experimental results. In order to develop an electrical model available for the circuit simulation, we programmed the aforementioned physical models with Verilog-A language and integrated them together. The developed electrical model can run on Cadence platform (a standard circuit simulation tool) and faithfully reproduce the behaviors of the FTJ.Then, using the developed FTJ model and STMicroelectronics CMOS design kit, we designed and simulated three types of circuits: i) FTJ-based random access memory (FTRAM), ii) two FTJ-based neuromorphic systems, one of which emulates spike-timing dependent plasticity (STDP) learning rule, the other implements supervised learning of logic functions, iii) FTJ-based Boolean logic block, by which NAND and NOR logic are demonstrated. The influences of the FTJ parameters on the performance of these circuits were analyzed based on simulation results.Finally, we focused on the reversal of the perpendicular magnetization driven by spin-Hall-assisted STT in a three-terminal MTJ. In this scheme, two write currents are applied to generate spin-Hall effect (SHE) and STT. Numerical simulation based on Landau-Lifshitz-Gilbert (LLG) equation demonstrates that the incubation delay of the STT can be eliminated by the strong SHE, resulting in ultrafast magnetization switching without the need to strengthen the STT. We applied this novel write approach to the design of the magnetic flip-flop and full-adder. Performance comparison between the spin-Hall-assisted and the conventional STT magnetic circuits were discussed based on simulation results and theoretical models.

In the past two decades, the interest in materials with strong spin-orbit coupling has attracted substantial attention because of the novel physical mechanisms they display and their potential for applications. The interface displaying large spin-orbit coupling has been recognized as a powerful platform to investigate the spin transport in ferromagnetic, antiferromagnetic, and non-magnetic materials, as well as their interfaces. Besides its rich physics, the related applications are also worth studying. The current-induced spin-orbit-torque arising from angular momentum transfer from the lattice to the spin system has substantial potential in recent state-of-art spin-orbit torque magnetic random access memory. In this dissertation, we have been interested in better understanding and characterizing the spin-orbit torque and spin Hall transport in various heterostructures of interest. We used the second harmonic method to determine the magnitude of the spin currents generation and transmission in Cu-Au alloy and Ir-Mn compound, respectively. We also characterized the device performance in selected heterostructures displaying either perpendicular MgO-based tunnel magnetoresistance or unusual surface states. Finally, we used these properties to approach spin-orbit torque magnetic random access memory through designing, fabricating, and characterizing the devices that focused on current-induced spin-orbit-torque magnetization switching.

Shallow Tunneling through highly populated areas of big cities is a challenging task. Almost in all the tunneling projects of shallow tunnel some or the other types of tunneling problems have been encountered and are still being faced. The stability of shallow tunnel is also influenced by many factors, primarily the in situ stress, geological structures, groundwater, rock mass quality, shape of tunnel etc. The design of shallow tunnel in past was almost purely a matter of experience. During last decays computational methods have been introduced as powerful design aids tool to arrive at safe and economical shallow tunnel structure. The purpose of this thesis work is to provide technical criteria and guidance for the design, and stability of Norra Länken shallow tunnel in rock for civil works projects. The design of shallow tunnels in highly dense areas is an iterative process. A good starting point is essential to the process and facilitates safe and economic design. Currently there are many practical two and three-dimensional software tools available for carrying out the task. This master thesis provides an overview of a methodology being used by tunneling experts, which captures the three-dimensional essentials of tunnel behaviour with two-dimensional analysis tools, PLAXIS. Though it is not a full and final situation and conclusion, but there is a lot to learn from such conditions .

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På senare år har samhället ställt allt högre miljökrav, när nya tunnlar ska anläggas. Ett område där kraven har höjts, är dräneringen av grundvatten på grund av inläckage till tunneln. Detta kan ge upphov till bland annat sinande brunnar, sättningsskador på byggnader samt påverkan på vegetation och naturmiljö. För att minimera problemen genomförs ett omfattande tät­ningsarbete i tunneln. Fullständig täthet uppnås dock sällan. Därför måste mätningar och kontroller utföras, både av grundvattennivåerna i närområdet och av det inläckande grund­vattenflödet i tunneln. Eftersom hanteringen av grundvattenfrågan länge varit nedprioriterad i branschen, behöver både planeringen och utförandet av mätningarna utvecklas, för att kunna möta samhällets allt hårdare miljökrav på området. Syftet med det här examensarbetet var att undersöka hur ramverket till den så kallade obser­vationsmetoden, kan användas till hanteringen av grundvatteninläckage vid tunnelbyggnad i berg. I denna metod förbereder man i projekteringen en preliminär design av konstruktionen. Samtidigt planerar man för åtgärder att sätta in, om mätningar (observationer) under bygg­tiden indikerar att designen behöver förändras. Därmed kan konstruktionen under projektets utförande anpassas till de faktiska förhållandena i marken. För att undersöka om observa­tionsmetoden är tillämpbar på hanteringen av inläckande grundvatten, studerades tunnel­projektet Norra länken i Stockholm. En jämförelse gjordes mellan hur grundvattenfrågan löstes i detta projekt och hur observationsmetoden definieras i Eurokoden samt i det till­hörande svenska tillämpningsdokumentet för geoteknik. Resultatet av den jämförande studien visade att utförandet i Norra länken till stor del överensstämde med hur observationsmetoden definieras i Eurokoden och med skrivningarna i tillämpningsdokumentet. Den ena skillnaden gällde mätanordningarnas tillförlitlighet. Den andra låg i hur det visas att det är tillräckligt hög sannolikhet, att den preliminära designen kommer att klara uppsatta krav. Med utveckling av dessa områden, borde det vara möjligt att fullt ut tillämpa observationsmetodens ramverk på hanteringen av grundvatteninläckage. Det visades dock att Eurokodens observationsmetod inte nödvändigtvis erbjuder den bästa lös­ningen, utan att varianter på denna också kan utgöra fullgoda alternativ. Examensarbetet visade också på några områden där förändringar kan göras, för att ge en bättre hantering av grundvattenfrågan i framtiden. Exempelvis borde bergtekniker komma in tidigt i projekteringen, för att göra kunskapsbilden mer komplett när de hydrogeologiska modellerna tas fram. Det borde också utredas om det finns bättre alternativ till injektering, när det är stor risk att detta inte är tillräckligt för att ge en tät konstruktion. Slutligen konstaterades det att det vore gynnsamt för alla inblandade parter om grundvatten­frågan hanterades på ett mer konsekvent sätt, eftersom detta skulle bidra till en ökad förut­sägbarhet och överskådlighet. Att följa det ramverk som Eurokodens observationsmetod erbjuder, är ett sätt att göra detta.

Bakgrund: Karpaltunnelsyndrom är den vanligaste typen av perifera nervinklämningar och orsakas av att medianusnerven blir klämd i karpaltunneln. De symtom som kännetecknar karpaltunnelsyndrom är nattliga domningar och smärta i hand och fingrar.  Syfte: Att undersöka effekt och evidens för nervmobilisering som behandling vid karpaltunnelsyndrom.  Metod: Sökningar genomfördes i databaserna PudMed, PEDro, CINAHL, AMED och Scopus med målet att identifiera randomiserade kontrollerade studier där nervmobilisering som behandling vid karpaltunnelsyndrom undersökts. Inkluderade artiklar kvalitetsgranskades enligt PEDro och de med hög kvalitet evidensgraderades enligt GRADEstud.  Resultat: Nio studier inkluderades i översikten. I alla studier observerades en positiv effekt av nervmobilisering avseende symtom och/eller funktion och en signifikant skillnad sågs mellan grupperna i 7 av 9 studier. Sex av nio studier hade hög kvalitet och tre hade låg kvalitet enligt PEDro-skalan. Evidensgraderingen visade att nervmobilisering som behandling vid karpaltunnelsyndrom har måttligt hög tillförlitlighet (+++). Små studier med få deltagare resulterade i ett poängs avdrag för bristande precision. Slutsats: Nervmobilisering tycks ge positiva effekter på funktion och symtom vid karpaltunnelsyndrom och har enligt GRADEstud måttligt hög tillförlitlighet. Nervmobilisering kan ge effekt även på lång sikt och kan minska behovet av operation men fler större studier med god kvalitet behövs för att kunna bekräfta detta. Nyckelord: Carpal tunnel syndrome, CTS, neural mobilization, nerve gliding / Background: Carpal tunnel syndrome is the most common type of peripheral neuropathy caused by compression of the median nerve in the carpal tunnel. The condition is characterized by night time tingling and pain in the hand and fingers.  Objective: The purpose of this study was to investigate the effects and evidence of neural mobilization as a treatment for carpal tunnel syndrome.  Methods: Searches were made in the databases PubMed, PEDro, CINAHL, AMED and Scopus to try and find randomized controlled trials that investigated neural mobilization as treatment for carpal tunnel syndrome. All of the included articles were appraised by the PEDro-scale and the level of evidence was graded using GRADEstud.  Results: Nine studies were included in this review. In all of the included studies a positive effect could be seen by neural mobilization on symptoms and/or function with a significant difference between groups in seven out of the nine studies. Six out of the nine studies had high quality and three had low quality according to the PEDro-scale. The grading of evidence showed that neural mobilization as treatment for carpal tunnel syndrome has a moderately high level of evidence (+++). Few studies with few participants resulted in one point deduction for lack of precision. Conclusion: Neural mobilization could have positive effects on symptoms and function in patients with carpal tunnel syndrome and has a moderately high level of evidence according to GRADEstud. Neural mobilization may have positive effects long term and could reduce need for surgery but more high quality research is needed to confirm this. Key words: Carpal tunnel syndrome, CTS, neural mobilization, nerve gliding.

The issue of the thesis is a construction of the Radejčín highway tunnel. Project contains all of the stages of construction. The total budget and time schedule were made for complete structure. The technological instruction was made for secondary lining of the tunnel. There is also a plan of security instruction, the list of risks on construction site, suggestion of fixed job contract, the plan of controlls and exams for making invert and upper vault of secondary lining. Another part is the project of construction site with three different drawing of construction sites and text part. The list of machines and devices is for the complete construction. It was added also a chosen construction details and evaluation of geotechnical monitoring.