Dissertations / Theses: 'Angle de tilt'

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Claudio, Gianfranco. "The effect of tilt angle on ion implanted profiles in silicon." Thesis, University of Surrey, 2004. http://epubs.surrey.ac.uk/843591/.

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This thesis reports a study, of the atomical and electrical properties, as function of tilt angle for VLSI technology in silicon. The ion species investigated have been arsenic, antimony and boron. Particular attention has been given to the dose loss and electrical activation as a function of the tilt angle in relation to the annealing conditions and the nature of the samples (crystalline or pre-amorphised). All the wafers have been implanted on the new SWIFT single wafer implanter realised by Applied Materials. Thermawave (TW) measurements performed on all samples implanted with As, B, and Sb show high uniformity of the dose implanted (less than 0.5%) on pre-amoiphised (a-Si) and crystalline silicon (c-Si). Rutherford backscattering spectrometry (RBS) has been performed in order to characterise the absolute dosimetry of the SWIFT implanter. Results obtained by RBS with an error of 1.4% have found no significant error in the implanter dosimetry. RBS measurements have also been performed to measure the retained dose for all samples before and after annealing for all the tilt angles investigated. Secondary Ion Mass Spectroscopy (SIMS) has been performed on antimony and boron implanted samples to measure the atomic profile as a function of depth in order to quantify the retained dose, the projected range, the straggle, the peak concentration and the junction depth. Hall measurements have been conducted to study the sheet resistance (Rs), Hall mobility (?H) and sheet earner concentration (Ns) as a function of the tilt angle for all the annealing conditions. Results show that Rs and Ns are functions of the tilt angle whilst ?H is independent of the tilt angle. Pre-amorphised wafers with germanium have also shown a better electrical activation (5%) and a lower junction depth (20-50 nm) compared to the crystalline ones for all the implanted samples. Differential Hall Measurements (DHM) have been performed on some samples for each ion species for particular tilt angles in order to evaluate any diffusion of the dopant for different annealing temperatures and compared with SIMS profiles. Comparison between simulated and experimental data has shown a good agreement only for the as implanted profiles. Computer simulation software is not able to give accurate annealed profiles due to the complex mechanism that involves defects and diffusion during annealing.

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Sano, Takahiro. "Biomechanics of Fixation of Distal Radius Fractures: Comparison between Volar Plate Fixator (VPF) and Non-Bridging External Fixator (NBX)." Scholarly Repository, 2008. http://scholarlyrepository.miami.edu/oa_theses/121.

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Fracture of the distal radius is one of the most frequent injuries, and it represents about 20% of all adults taken into emergency rooms. A number of studies suggest various methods to reduce the dislocation and to secure fragments of the distal radius. In this study, the Non-Bridging External Wrist Fixator System (NBX), a pre-market-released product manufactured by NUTEK Inc. was biomechanically assessed by comparing with the Universal Distal Radius System (Volar Plate Fixator: VPF), a market-released product manufactured by Stryker Co. The comparison was performed in several parameters, which were wrist motion, radial tilt angle, radial length, volar tilt angle, stiffness, and failure load. Five pairs of fresh human cadaver arms were used for this study. The wrists were tested to obtain x-ray images for 1 normal and 2 injury conditions (intact, fractured, and fixed), 2 load conditions (gravity only and torque applied), and 4 postural conditions (volar flexion, dorsiflexion, ulnar deviation, and radial deviation). These tests yielded 24 (3×2×4) x-ray images for each wrist, and the images were analyzed to obtain the data for each parameter. Although the results were not statistically significant in some conditions, NBX fixation limited wrist motion more than VPF fixation. This result can be explained not only by the difference in the ability of fixation, but also by the difference in the surgical trauma (NBX is less invasive than VPF). Furthermore, in the measurement of radial tilt angle, radial length, and volar tilt angle, NBX was more effective than VPF to reduce and secure the bone fragments of the distal radius. In destructive test, the NBX is less strong than VPF. However, NBX is strong enough to sustain the expected forces of daily activity.

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Dock, Melissa. "Influence of pedometer tilt angle on step counting validity during controlled treadmill walking trials." Thesis, Montana State University, 2008. http://etd.lib.montana.edu/etd/2008/dock/DockM0508.pdf.

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Pedometers are tools frequently used to monitor walking-related physical activity patterns of overweight and obese populations. However, there is a known association between increasing body mass index (BMI) and decreasing pedometer accuracy. The decrease in pedometer accuracy has been attributed to tilt angle, but the specific tilt angle where pedometers fail to maintain accuracy is unclear. PURPOSE: The purpose of this study was to test two popular pedometer mechanisms, accelerometry- and pendulum-based, to determine the specific tilt angle where the pedometers fail to maintain step counts accurately. METHODS: Twenty subjects (10 men, MeanÂ±SD: 25.4Â±4.2 yrs, 184.4Â±5.3 cm, 76.7Â±6.3 kg; 10 women: 21.6Â±3 yrs, 166.1Â±6.3 cm, 56.7Â±6.7 kg) walked two sets of 21 trials at a combination of treadmill speed (67.0, 80.4, 93.8 m/min) and tilt angle (-30,-20,-10, 0,+10,+20,+30Â°) while wearing two pedometers; the experimental pedometer attached to a custom-built pedometer gimbal for altering tilt angle, and the control pedometer in a neutral position (Â±2Â° of 0Â°). The pedometers were worn on each hip just anterior to the iliac crest in line with the mid-axillary line of the thigh. The first set of trials tested one pedometer mechanism, while the second set of trials tested the second pedometer mechanism in a counterbalanced order. Mean steps from the experimental pedometer were compared to the control pedometer for each trial (Î”Step=Experimental-Control) using a 3-factor RMANOVA at an alpha level of 0.05. RESULTS: Mean Î”steps for the accelerometry-based pedometer and the pendulum-based pedometer differed significantly (P<0.05) at tilt angles >Â±10Â° for treadmill speeds 0Â° (-30, -20, -10, +10, +20, +30Â°, respectively). CONCLUSIONS: Increasing tilt angle caused a decrease in pedometer accuracy for both pedometer mechanisms, although the accelerometry-based pedometers were less affected. Negative tilt angles had less effect on pedometer accuracy than positive tilt angles, and the combination of increasing positive tilt angle and slower speeds had the greatest impact on step count accuracy.

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Hopkins, Jonathan B. (Jonathan Brigham). "The effect of probe tilt angle on the quality of scanning tunneling microscope measurements." Thesis, Massachusetts Institute of Technology, 2005. http://hdl.handle.net/1721.1/32888.

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Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2005.
Includes bibliographical references (p. 39 ).
The effect of probe tilt angle on the quality of Scanning Tunneling Microscopy (STM) measurements was explored. A small but consistent improvement in slope accuracy was documented lending some support to the effort to develop a new, five-axis STM capable of tilting in a controlled manner while scanning. The objective of such a machine would be to allow its probe to trace the sample's contour with greater accuracy than the currently available three-axis STM can. It is postulated that an STM with a probe that can change its roll and pitch in addition to its position along the traditional x, y, and z axes would be capable of reducing imaging errors produced as a result of geometric constraints, lateral electron discharge effects, and the tendency for the tip to bend during scanning due to electrostatic surface forces. In order to quantify the effects of incorporating probe tilt into the scanning process, a traditional, three-axis STM was manipulated in a way that allowed a standard sample grid to be imaged using a probe that was placed at seven different angles of tilt ranging from -13 to +13 degrees. Twenty-five different cavities in a standard STM scanning sample were scanned at these seven angles to determine notable trends and effects in the images produced.
(cont.) It was determined that for each degree of angle change in the tilt of the probe, the slopes of the cavity walls imaged improved by an amount of slope equal to approximately 0.001 nm/nm, which corresponds to 0.0093% less imaging error. This seemingly trivial improvement in wall slope is significant in light of the fact that the change in slope per degree of probe tilt is on the same order of magnitude as the slopes of the cavity walls measured by the STM.
by Jonathan B. Hopkins.
S.B.

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TORRES, DIEGO FERNANDO CELIS. "NUMERICAL STUDY OF THE INFLUENCE OF TILT VALVE ANGLE ON BLOOD FLOW IN AN AORTIC MODEL." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2017. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=32320@1.

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PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO
COORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIOR
PROGRAMA DE EXCELENCIA ACADEMICA
A substituição de válvula aórtica por cateter (Transcatheter Aortic Valve Replacement, TAVR) tornou-se uma poderosa alternativa para pacientes com estenose aórtica e com alto risco de serem submetidos à cirurgia tradicional de peito aberto. O conhecimento da distribuição da pressão, bem como a tensão cisalhante na superfície da aorta podem ajudar a identificar regiões críticas, onde o processo de remodelamento da aorta pode ocorrer. O objetivo do presente trabalho é avaliar numericamente a influência do posicionamento do orifício da válvula protética no campo de escoamento. O estudo foi realizado com base em um paciente submetido a TAVR. Um modelo 3D foi gerado a partir de angiotomografia e de segmentação de imagens da aorta. Dados experimentais obtidos anteriormente na mesma geometria indicaram que o fluxo do jato através da válvula de entrada é de natureza turbulenta. O escoamento foi determinado numericamente com o software comercial FLUENT. A turbulência foi modelada com o modelo de dois equações k-omega SST. Para representar um fluxo pulsátil, foram impostos diferentes fluxo de massa na entrada da válvula. Para todas as vazões investigadas, obteve-se um padrão de escoamento semelhante. Mostrou-se que uma pequena variação dos ângulos de inclinação pode modificar a natureza do fluxo, deslocando a posição dos vórtices e alterando a localização das regiões de alta tensão de cisalhamento, assim como de alta pressão, na superfície interna da aorta. Mostrou-se também que um aumento da intensidade da turbulência na entrada diminui os valores de tensão cisalhante e de pressão nas paredes da aorta. Essas características hemodinâmicas podem ser relevantes no processo de remodelação aórtica e os estresses mecânicos podem influenciar na durabilidade da prótese valvular.
Transcatheter Aortic Valve Replacement (TAVR) has become a powerful alternative for patients with aortic stenosis and a high surgical risk to face a traditional open chest surgery. The knowledge of the pressure distribution as well as shear stress at the aortic surface may help identify critical regions, where aortic remodeling process may occur. The purpose of the present work is to evaluate numerically the influence of the positioning of the prosthetic valve orifice in the flow field. The study was carried out on the basis of a particular patient who had undergone a TAVR. A 3D model was generated from computed tomography angiography and image segmentation of the aorta. Experimental data previously obtained in the same geometry indicated that the jet flow through the inlet valve is turbulent flow. The flow field was numerically determined with the commercial software Fluent. The turbulence was modeled with the two-equation k-omega SST model. To represent a pulsatile flow, different mass flow rates were imposed at the inlet valve. Similar flow pattern was observed for all flow rates investigated. It was shown that small variations of the tilt angle can modify the nature of the flow, displacing the position of the vortices and altering the location of high shear stress, as well as high pressure, at the aortic inner wall. It was also shown that an increase of the turbulent intensity at the entrance decreases the values of shear stress and pressure on the walls. These hemodynamic features may be relevant in the aortic remodeling process and the mechanical stresses may influence the durability of the valve prosthesis.

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Alsulaiman, Mohamad, and Najmeh Mohammadi. "Optimal Pitch Distance and Tilt Angleof PV Power Plant for Different Climate." Thesis, Högskolan Dalarna, Energiteknik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:du-35528.

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Finding the optimum inter-row spacing and installation tilt for tilted or ground mounted PV systems is a big issue in designing the large-scale PV systems. Increasing the array spacing leads to higher annual generated energy because of the reduced impact of row-shading, but on the other hand, it increases costs of land purchase/lease and wiring costs. Many compromises between performance and cost should be done to design an optimum large-scaled solar plant. One of the criteria in designing of solar power plants is reducing of LCOE, which reflects the cost of every unit of generated energy. Site locations have large impacts on the optimal design of pitch distance and title angles, but such impacts have not been studied extensively in the existing studies, so it is going to bridge this research gap in this thesis. The main purpose of this research is to investigate the impact of climate conditions on the pitch distance and tilt angle for large-scale PV plant and finding the optimal pitch distance and tilt according to the least cost of production. The impact of climate and meteorological data on the self-shading loss and yield of energy are investigated through a simulation tool, which is PVsyst software here, in different tilt angles and distances between rows. The different climates can be considered by choosing site locations in different latitudes to cover all climate zones. Six cities in temperate climate, three cities in tropic climate and one city in polar climate have been selected. LCOE minimizing is a measure in finding the optimum tilt and pitch distance for a 1 MW solar system installed in different latitudes. In this study the type, size and cost of components have been assumed constant in different climate conditions. There is a wide range of variability in some economic indicators like interest rate and discount rate as well as the cost of land in different climates or even countries in the same climate; then to highlight the impacts of climate conditions on the optimal tilt and pitch distance, these parameters were assumed to be constant in this study. The results show the optimal tilt of angles increases with getting far of equator in a range between 0° and 40° to capture more direct sunlight, and the optimal raw spacing grows in further locations to equator in a range between 4 m to 11 m to reduce self- shading loss. Moreover, the best module configuration for PV arrays (portrait or landscape) can be different in different climates.

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Pellegrene, Brittany Ann. "Optimization of Transition Temperatures and Tilt Angle in SmCP_A Phase Bent-Core Liquid Crystals." Kent State University Honors College / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=ksuhonors1430258781.

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Gugale, Gaurav Subhash. "Development of Analytical Equations for Optimum Tilt of Two-Axis and Single-Axis Rotating Solar Panels for Clear-Atmosphere Condition." Wright State University / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=wright148459939571045.

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Matsfelt, Johanna. "Study on the influence of the electrode tilt angle in GTAW doing CFD simulation of the heat source." Thesis, Högskolan Väst, Avd för maskinteknik, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:hv:diva-5801.

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Alhaidari, Salah. "A Look at the Optimum Slope of a Fixed Solar Panel for Maximum Energy Collection for a One Year Time Frame." Wright State University / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=wright1515545054060599.

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Yu, Xueyang. "FINITE ELEMENT ANALYSIS OF FACTORS INFLUENCING DISPLACEMENT MEASUREMENT USING PLANAR INDUCTIVE SENSORS." University of Akron / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=akron1586791378508492.

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Ben, Hamida Malek. "Analyse et validation du comportement directionnel des outils de forage couplés aux systèmes de forage dirigé." Thesis, Paris, ENMP, 2013. http://www.theses.fr/2013ENMP0054/document.

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Nous présentons dans ce mémoire un modèle d'interaction outil-roche qui calcule les efforts de forage en fonction du déplacement dans la roche d'un outil de forage de type PDC, et permet d'évaluer ses propriétés directionnelles, à savoir, son indice d'anisotropie (steerability) et son angle de walk. Le mouvement de l'outil est défini par une translation suivant trois axes et une rotation suivant deux axes. L'angle de tilt, qui définit l'inclinaison de l'outil par rapport à l'axe du trou en cours de forage, est pris en compte dans le calcul des surfaces d'interactions effectives entre les différentes composantes de l'outil (structure de coupe, garde active et garde passive) et la roche. Ce modèle outil est établi à partir d'une modélisation de la coupe de roche par un taillant. Ce modèle de coupe élémentaire est construit de manière à être applicable aux différentes parties de l'outil. Les efforts élémentaires de coupe sont intégrés sur toute la structure de l'outil de forage afin de calculer ses propriétés directionnelles. Le modèle d'interaction outil-roche est validé à partir d'essais de forage directionnel réalisés sur un banc spécialement conçu pour reproduire le comportement des systèmes de forage dirigé existants. Il constitue un outil d'aide à la décision pour la sélection de l'outil de forage en fonction du système au bout duquel il sera fixé. Ce modèle pourra aussi être intégré dans une boucle de régulation automatique ou semi-automatique de contrôle et de correction de la trajectoire en temps réel
This work deals with the formulation of global relationships between kinematic variables describing the penetration of a PDC bit into the rock and drilling forces acting on it. This allows us determine the bit directional properties in terms of steerability, which corresponds to the bit lateral aggressiveness, and walk, which describes the bit azimuth displacement with respect to the side force. The bit kinematic quantities are divided into a three-axis penetration vector and a two-axis angular penetration vector. The bit tilt, which describes the angle between the bit revolution axis and the borehole tangent, is used to compute the effective interaction surface between the bit's different components (cutting structure, active gauge and passive gauge) and the rock. A new cutter-rock interface law is set up and experimentally validated in order to compute elementary forces acting on all parts of a drill bit. Bit directional properties are computed after the integration of these elementary forces. The bit-rock interaction model is experimentally validated with directional drilling tests held on a full-scale drilling bench developed to reproduce Rotary Steerable Systems (RSS) directional behavior. Tests and theoretical results enabled us to fully understand the roles of tilt angle, bit design, operating parameters and rock properties in the deviation process of a PDC bit. The bit-rock interaction model is a decision support tool for optimal drill bit selection according to the RSS being used. It could also be embedded in a real-time Closed-Loop Guided Directional Drilling controller in order to correct the drilling direction or follow a planned borehole trajectory

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Grieshaber, Derrick. "Assessing the Reliability of Two Orthopedic Special Tests to Determine Hip Flexor Contracture with the Assessment of Pelvic Tilt Angle during a Back Squat." Thesis, North Dakota State University, 2018. https://hdl.handle.net/10365/28857.

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Orthopedic specialists use Special Tests to determine a pathology?s presence. Hip flexor contracture is linked to injury predisposition and postural anomalies. This research examined reliability for the Modified Thomas and Ely?s Special Tests when evaluating hip flexor contracture, and its effect on dynamic exercise. Twenty adults were randomized in a study and analyzed for hip flexor contracture. Dartfish Motion Analysis measured hip and knee flexion angles. Participants performed isometric squats to determine their maximal voluntary isometric contraction, which was later used to calculate exercise prescription for the eight-repetition dynamic back squat. Inter-rater reliability was slight to fair for iliopsoas contracture during the Modified Thomas Test. Overall analysis of pre-/post-test pelvic tilt and dynamic pelvic tilt between repetitions was not statistically significant (p<.05). Hip flexion between repetitions was statistically significant (p=.016). Clinicians should exert caution when defining pathology utilizing Special Tests and the effect of hip flexor contracture on dynamic movement.

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Stonytė, Jolita. "Atmosferinių veiksnių poveikis saulės fotovoltinių įrenginių charakteristikoms." Master's thesis, Lithuanian Academic Libraries Network (LABT), 2013. http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2013~D_20130619_130938-60126.

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Efektyvų saulės jėgainių veikimą labai lemia geografinė padėtis, nes Saulės spindulių srautas žemės paviršiuje pasiskirsto netolygiai. Lietuva yra vidutinio klimato juostos šiaurinėje dalyje, kur dažnas debesuotumas, rūkas, lietus, sniegas, įvairios kilmės dulkės, tai veiksniai lemiantys fotovoltinių sistemų efektyvumo sumažėjimą. Baigiamajame magistro darbe nagrinėjami saulės fotovoltiniai įrenginiai, gamybos technologijos, rūšys, pagrindinės charakteristikos, konstrukcijų montavimo ypatybės vidutinių platumų regionuose. Aptarta įvairių šalių patirtis eksploatuojant saulės jėgaines skirtingomis klimato sąlygomis. Išnagrinėti pagrindiniai veiksniai, lemiantys jėgainės našumą. Darbe analizuojamas sniego, dulkių, lietaus lašų poveikis fotovoltinių įrenginių charakteristikoms. Atlikus eksperimentinius tyrimus, vertinami patirti nuostoliai dėl atmosferinių veiksnių įtakos. Aprašyti tyrimų ir analizės metodai. Išnagrinėjus eksperimentinių tyrimų rezultatus, pateikiamos baigiamojo darbo išvados ir pasiūlymai. Darbą sudaro šešios dalys: įvadas, saulės energetikos srities literatūros apžvalga, tyrimams naudotos medžiagos, metodai ir aparatūra, tyrimų rezultatai ir jų aptarimas, išvados ir pasiūlymai, literatūros sąrašas. Darbo apimtis – 73 p. teksto be priedų, 63 pav., 4 lent., 41 bibliografinis šaltinis.
The efficiency of solar power plants is strongly influenced by geographic location, because the solar radiation flux on the surface is distributed very irregular. Lithuania is situated in a humid continental zone in the northern part, where is frequent cloud cover, fog, rain, snow, dust of various origins, these are the factors determining the efficiency of photovoltaic systems. The thesis deals with solar photovoltaic devices, manufacturing technology, types, main characteristics, structural features of mounting at medium latitude regions. Discussed the experience of different countries operating solar power plants in different climatic conditions. Analyzed the major factors affecting plant performance. This paper analyzes the impact of snow, dust, rain drops on the characteristics of solar photovoltaic equipment. After experimental study measured the efficiency and losses due to atmospheric factors. Described the research and analysis methods. After considering the experimental results, conclusions are presented. Structure: introduction, solar energy literature review, materials and methods used in research, results and discussion, conclusions, references. Thesis consist of: 73 p. text without appendixes, 63 pictures, 4 tables, 41 bibliographical entries.

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Forslund, John. "Optimering och dimensionering av ett solcellssystem till ett flerbostadshus i Mellansverige : En beräknings- och simuleringsstudie." Thesis, Högskolan i Gävle, Avdelningen för bygg- energi- och miljöteknik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-26981.

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Solkraft kan täcka hela jordens energibehov många gånger utan att släppa ut växthusgaser eller andra giftiga ämnen vid drift och räknas därför till en hållbar och förnyelsebar energikälla. Solkraft är därför en lämplig kandidat till att ersätta dagens ej hållbara fossilbaserade energisystem. Priset för solceller har sjunkit mycket de senaste åren. Samtidigt som Sverige och EU har som mål att minska koldioxidutsläpp ges både skattereduktion för såld överskottsel från solkraft och ett investeringsstöd. Därför kan det eventuellt vara lönsamt att installera solceller i Sverige trots begränsad solinstrålning. Det krävs att återbetalningstiden är rimlig för att privatpersoner skall bestämma sig att investera i solceller. Miljövinster är inte alls motiverande för privatpersoner enligt undersökningar. Därför bör solcellsanläggningar optimera och dimensioneras för maximal ekonomisk lönsamhet för att öka chanserna att investeringen blir av. Det här arbetet undersöker hur ett optimalt solcellssystem ska se ut ur ett ekonomiskt perspektiv för en bostadsförening bestående av 25 lägenheter i Mellansverige under olika ekonomiska förutsättningar. Störst fokus ligger på att analysera hur lutningsvinkeln förändrar resultatet. Elproduktionen hos olika konfigurationer av solcellsanläggningar simulerades fram. Dessa resultat ställdes mot byggnadens elanvändning för att beräkna hur mycket el som används till för att spara inköpt el och hur mycket som säljs för att utifrån det beräkna lönsamheten. Mest el produceras vid lutningsvinkeln 40° vilket ger marginellt mer än 30° som taket lutar. Det visar sig att lutningsvinkeln kan justeras för att öka lönsamheten men det är endast ett fåtal procent som mest. Skillnaden är som störst för små anläggningar som precis täcker baslasten för fastigheten. Bästa vinkeln för dessa mindre system är 45°. Det är svårt att motivera det dyrare montaget för att vinkla upp modulerna då taket redan lutar nära optimalt. Skillnaden mellan köpt och sparad el är liten om skattereduktion ges. Det är dock oklart hur länge skattereduktionen varar så det är därför säkrare att dimensionera utifrån sitt eget elbehov. Ett solcellssystem dimensionerat för att sälja mycket överskottsel skulle kunna bli en stor förlustaffär. Om solkraft får större plats i Sveriges elproduktion kan den ge upphov till högre globala koldioxidutsläpp beroende på vilket energislag den ersätter. Samtidigt tar det längre tid i Sverige jämfört med andra länder innan en solcell kan beräknas koldioxidneutral då det redan är mycket låga koldioxidutsläpp i Sveriges elmix kombinerat med relativt låg solinstrålning. Det innebär att solkraft ur ett miljöperspektiv är tvivelaktigt i Sverige.
Solar power is estimated to be able to cover the whole earths energy demand many times without releasing greenhouse gases or other pollutants while they operate and is therefore considered a renewable energy source. Solar power is therefore a suitable replacement to today’s fossil based energy systems. The cost for solar cells have decreased a lot in recent years. At the same time Sweden and the European Union have goals set for reducing the amount of carbon dioxide released so a tax reduction is given to those who sells overproduced electricity from solar power to the grid. This means it could eventual be profitable even in Sweden for installing solar power even though the sun doesn’t shine as much that close to the poles. It is suitable to install solar panels at buildings since it is the building and service sector that uses the most electricity in Sweden. It must be profitable for private investors before they make the choice to invest in solar panels. Environmental benefits are not as attractive for private investors. Should the solar arrays be optimized in such way that the profit is maximized the investment is more likely to occur. This paper examines how an optimal solar cell system should look like from a profitable perspective for a building with 25 apartments in the middle of Sweden under different economic conditions. Most focus is directed towards how the tilt angle affects the results. The electricity production of different configurations of solar panels was simulated. These results were then compared to the electricity demand for the building so the amount used for self-consumption and how much is sold to the grid could be calculated and from that calculate how profitable that system is. Most electricity is produced at the tilt angle of 40°, but marginally more than 30° which the roof is tilted. The difference between tilt angles are just a few percent at most. The difference is most noticeable when the system is just big enough to cover the base electricity demand. The best tilt angle for those systems are 45°. It is hard to advocate for more expensive mounting for bigger systems since the roof already is close to the optimal tilt angle. The value for saved and sold electricity is very close to each other if tax reduction is given. It’s however uncertain for how long tax reduction will last. It is much safer to size a solar array to cover the building’s electricity demand. It could be very costly to size a solar array which relies upon selling electricity with today’s economic condition. However, solar power is questionable in Sweden in an environmental perspective.

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Ben, Hamida Malek. "Analyse et validation du comportement directionnel des outils de forage couplés aux systèmes de forage dirigé." Electronic Thesis or Diss., Paris, ENMP, 2013. http://www.theses.fr/2013ENMP0054.

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Nous présentons dans ce mémoire un modèle d'interaction outil-roche qui calcule les efforts de forage en fonction du déplacement dans la roche d'un outil de forage de type PDC, et permet d'évaluer ses propriétés directionnelles, à savoir, son indice d'anisotropie (steerability) et son angle de walk. Le mouvement de l'outil est défini par une translation suivant trois axes et une rotation suivant deux axes. L'angle de tilt, qui définit l'inclinaison de l'outil par rapport à l'axe du trou en cours de forage, est pris en compte dans le calcul des surfaces d'interactions effectives entre les différentes composantes de l'outil (structure de coupe, garde active et garde passive) et la roche. Ce modèle outil est établi à partir d'une modélisation de la coupe de roche par un taillant. Ce modèle de coupe élémentaire est construit de manière à être applicable aux différentes parties de l'outil. Les efforts élémentaires de coupe sont intégrés sur toute la structure de l'outil de forage afin de calculer ses propriétés directionnelles. Le modèle d'interaction outil-roche est validé à partir d'essais de forage directionnel réalisés sur un banc spécialement conçu pour reproduire le comportement des systèmes de forage dirigé existants. Il constitue un outil d'aide à la décision pour la sélection de l'outil de forage en fonction du système au bout duquel il sera fixé. Ce modèle pourra aussi être intégré dans une boucle de régulation automatique ou semi-automatique de contrôle et de correction de la trajectoire en temps réel
This work deals with the formulation of global relationships between kinematic variables describing the penetration of a PDC bit into the rock and drilling forces acting on it. This allows us determine the bit directional properties in terms of steerability, which corresponds to the bit lateral aggressiveness, and walk, which describes the bit azimuth displacement with respect to the side force. The bit kinematic quantities are divided into a three-axis penetration vector and a two-axis angular penetration vector. The bit tilt, which describes the angle between the bit revolution axis and the borehole tangent, is used to compute the effective interaction surface between the bit's different components (cutting structure, active gauge and passive gauge) and the rock. A new cutter-rock interface law is set up and experimentally validated in order to compute elementary forces acting on all parts of a drill bit. Bit directional properties are computed after the integration of these elementary forces. The bit-rock interaction model is experimentally validated with directional drilling tests held on a full-scale drilling bench developed to reproduce Rotary Steerable Systems (RSS) directional behavior. Tests and theoretical results enabled us to fully understand the roles of tilt angle, bit design, operating parameters and rock properties in the deviation process of a PDC bit. The bit-rock interaction model is a decision support tool for optimal drill bit selection according to the RSS being used. It could also be embedded in a real-time Closed-Loop Guided Directional Drilling controller in order to correct the drilling direction or follow a planned borehole trajectory

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17

Chanouian, Serg. "What If We Tilt the AOD? : Developing a numerical and physical model of a downscaled AOD converter to investigate flow behaviour when applying an inclination." Thesis, KTH, Materialvetenskap, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-254912.

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In a scrap based stainless steel plant the dominant process for carbon reduction is the Argon oxygen decarburisation process (AOD). The process goes through three steps: decarburisation, reduction and desulphurisation where the main challenge is to oxidise carbon to CO without oxidising the expensive chromium. The general practical approach is to inject a mixture of oxygen and an inert gas, like argon or nitrogen, through tuyeres at the converter side starting with a high amount of oxygen gas which followingly is reduced as the inert gas is increased during the decarburisation steps. This allows for a decrease in partial pressure for the CO bubbles which is thermodynamically favourable for carbon oxidation. Recent studies have shown that an aged AOD converter with a worn lining can decarburise the melt faster than a fresh vessel due to favourable thermodynamic conditions occurring since the bath height is lower in the aged converter. The studies show 8-10% savings of oxygen gas which have led to an interest to study the matter. One of two approaches are taken in the present work with the focus to develop a numerical model that simulates a downscaled AOD converter with applied inclinations that is to be validated through physical modelling. A 75-ton industrial converter was downscaled for water-air experiments where three inclination angles namely 0, 5.5 and 14° were studied with focus on mixing time and penetration length. The physical model was replicated for computational fluid dynamics (CFD) modelling using the Euler-Euler approach in ANSYS Fluent. The models show rather good similarities when comparing gas penetration length, flow structure and mixing time however needs some complementary work and final adjustments before upscaling as well as coupling with thermodynamic modelling can be done.
Den dominerande processen för kolfärskning vid skrot baserad rostfri ståltillverkning är AOD- processen (Argon Oxygen Decarburisation). Processen går igenom tre steg, kolfärskning, reducering av krom och svavelrening där de största utmaningarna ligger i att oxidera kol utan att oxidera krom. I praktiken gör detta genom att injicera en blandning av argon och syrgas från sidan av AOD-konvertern för att sänka partial trycket av den kolmonoxid som bildas när kol oxideras. Syftet är att göra det mer termodynamiskt fördelaktigt att oxidera kol i systemet. Den injicerade blandgasen har olika förhållanden under kolfärskning med en hög andel syrgas i början som sedan sänks genom processen tills bara argon injiceras. Tidigare studier har visat att kolfärskningen är en funktion av konverterns ålder där ju äldre en konverter är desto snabbare går kolfärskning. Enligt studierna har det visats att 8-10% mindre syrgas eller användning av reducerings medel kan uppnås i en gammal konverter vilket har väckt ett intresse för vidare studier. I detta arbete har en av två metoder prövats för att undersöka om man kan applicera det som sker i en gammal konverter till en ny. En numerisk modell av en nerskalad AOD-konverter har utvecklats och validerats mot en vattenmodell då konvertern vinklas. En 75-tons konverter nerskalades till en vattenmodell där vinklarna 0, 5.5 och 14° studerades med fokus på blandningstid och penetrations djup. Vattenmodellen gjordes om till en numerisk modell som använde Euler-Euler metoden i ANSYS Fluent. Modellerna visade likheter gällande penetrationsdjup, flödes struktur och blandnings tid men kräver en del justeringar innan en uppskalning samt koppling till termodynamisk modellering kan ske.

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Fournier, Marc. "Influência do alinhamento sagital espinopélvico na espondilolistese lombar: revisão bibliográfica." Bachelor's thesis, [s.n.], 2018. http://hdl.handle.net/10284/7017.

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Projeto de Graduação apresentado à Universidade Fernando Pessoa como parte dos requisitos para obtenção do grau de Licenciado em Fisioterapia
Introdução: a espondilolistese degenerativa é uma patologia comum que pode atingir até 11,5% da população mundial, porém a sua patogénese ainda não é totalmente conhecida, tornando-se relevante investigar fatores de risco anatomofuncionais que possam influenciar a incidência, prevalência ou o agravamento desta patologia. Objetivo: analisar os parâmetros do alinhamento sagital espinopélvico e os seus impactos na espondilolistese lombar degenerativa. Metodologia: pesquiza computorizada na base de dados PubMed. Após a seleção dos estudos foi efetuada uma análise de qualidade metodológica com o Critical Appraisal Skills Programme (CASP). Resultados: nesta revisão foram integrados 9 artigos, com um total de 2445 pacientes de idades compreendidas entre 18 e 88 anos, dos quais se recolheram dados com o intuito de avaliar a correlação dos componentes biomecânicos da sacroilíaca com a presença de espondilolistese lombar. Conclusão: constata-se que a morfologia da sacroilíaca é influenciada pela incidência pélvica, a qual interfere com os outros parâmetros pélvicos e no equilíbrio sagital, levando, assim, à génese da patologia, ou seja, da espondilolistese.
Background: degenerative spondylolisthesis is a common disease which could affect 11,5% of mondial population, but we do not know exactly the reasons of her pathogenesis. Due to the importante incidence, many studies research risk factors and prevalence that could influence the apparition and complication of pathology. Authors now make a relationship between sagital spinopelvic alignment and degenerative spondylolisthesis. As reported in literature, sacroiliac's angles and morfology have a leading role in this pathology. Objectives: our objectif in this study is to evaluate sagital spinopelvic alignment parameters in order to determining their implication in lumbar degenerative spondylolisthesis. Methodology: computerized literature search in the databases PubMed to identify experimental articles. After the selection of the studies, an analysis of methodological quality was made with Critical Appraisal Skills Programme (CASP). Results: in this study we have been evaluating 9 articles with a total of 2445 patients aged 18 to 88, in each cas e, the parameters os sagital spinopelvic alignment has been calculated to be correlated with lumbar degenerative spondylolithesis. Conclusion: it is verified that the sacroiliac's morphology is influenced by the pelvic incidence, which interferes with the other pelvic parameters like the pelvic tilt, which modificate the sagital alignment, taking to the genesis of the spondylolistesis.
N/A

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19

Strömstedt, Erland. "Submerged Transmission in Wave Energy Converters : Full Scale In-Situ Experimental Measurements." Doctoral thesis, Uppsala universitet, Elektricitetslära, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-179740.

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Different wave power technologies are in development around the world in different stages of prototype testing. So far only a few devices have been deployed offshore at full scale for extended periods of time. Little data is published about how these different devices perform. This thesis presents results from experiments with the full-scale offshore wave energy converters at the Lysekil research site on the Swedish west coast. The theories, experiments, measurements, performance evaluations and developments of the submerged transmission in the direct driven permanent magnet linear generator are in focus. The reciprocating submerged transmission fulfills the purpose of transmitting the absorbed mechanical wave energy through the capsule wall into the generator, while preventing the seawater from entering the capsule and reducing the life time of the converter. A measuring system with seven laser triangulation sensors has been developed to measure small relative displacements between piston rod and seal housing in the submerged transmission with excellent accuracy for the purpose of evaluating both functional behavior and successive wear in-situ. A method for calculating relative tilt angles, azimuth angles, differential tilt angles, and successive wear in the submerged transmission has been developed. Additional sensors systems have been installed in the converter enabling correlation and a thorough investigation into the operating conditions of the transmission and the converter. The thesis presents unique results from the measurements. A data acquisition system transmits the signals from the converter on the seabed to an onshore measuring station. Results are presented in time-, frequency- and the time-frequency domain. The results have given important information for further development of the submerged transmission, which is important to the survivability of the system. The thesis describes the status of research, and is a step that may influence future designs of wave energy devices for reaching survivability and a cost-effective renewable energy system.

Published is a preprint version of the full text and should be combined by the errata.

The Lysekil Wave Power Project

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20

Paiva, Gabriel Mendonça de. "Dimensionamento de um sistema fotovoltaico conectado à rede a partir das características de inclinação e orientação dos módulos fotovoltaicos." Universidade Federal de Goiás, 2016. http://repositorio.bc.ufg.br/tede/handle/tede/6426.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES
This study aimed to evaluate the design of a grid-connected photovoltaic (PV) system according to the positioning of the modules which compose the generator depending on tilt and azimuth angles in Goiânia, Goiás. In that purpose, a review of the literature was carried out concerning the main methods of inverter sizing ratio analysis applied to grid-connected PV systems. Starting from an hourly average climate measurement database from Goiania, an algorithm was developed to search for the ideal local inverter sizing ratio, considering the use of polycrystalline module technology. The parameters used in the analysis were provided by the manufacturers of the componentes used in the grid-connected PV system in installation at the Electrical, Mechanical and Computational Engineering School (EMC) from Federal University of Goias (UFG), which nominal power is 33.84 kWp. An inverter sizing ratio band of 0.54 to 0.77 was obtained for a -90° to +90° azimuth angle variation and 0° to 90° tilt angle variation. The potential of financial indicators improvement was verified and it was estimated a potential reduction in the levelized cost of energy above 10% comparing the inverter sizing ratio improved system to an unitary inverter sizing ratio system.
Este estudo tem como objetivo avaliar o dimensionamento de um sistema fotovoltaico conectado à rede (SFCR) de acordo com o posicionamento dos módulos que compõem o gerador quanto ao ângulo de inclinação e ao ângulo azimutal em Goiânia, Goiás. Para isso foi realizada uma revisão da literatura quanto às principais metodologias de análise do fator de dimensionamento do inversor (FDI) aplicado a SFCRs. A partir de uma base de dados em intervalos horários de medições climáticas de Goiânia desenvolveu-se um algoritmo para busca do FDI ideal para a localidade, considerando o uso de módulos de silício policristalino (p-Si). Os parâmetros utilizados na análise foram os parâmetros fornecidos pelos fabricantes dos componentes utilizados no SFCR em instalação da Escola de Engenharia Elétrica, Mecânica e de Computação (EMC) da Universidade Federal de Goiás (UFG), cuja potência nominal é de 33,84 kWp. Os métodos de análise do FDI foram comparados e foi considerado mais adequado neste estudo o método das perdas máximas anuais por limitação de potência no inversor. A faixa de FDI obtida para uma variação de -90° a +90° no ângulo azimutal e de 0° a 90° no ângulo de inclinação foi da ordem de 0,54 a 0,77. O potencial de aprimoramento de indicadores financeiros por meio do FDI foi verificado e foi estimada uma potencial redução acima de 10% do custo da energia produzida comparando o aperfeiçoamento do FDI com um FDI unitário.

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Єріцян, Багіш Хачикович. "Синтез комбінованої системи нахилу кузова швидкісного електричного рухомого складу." Thesis, НТУ "ХПІ", 2016. http://repository.kpi.kharkov.ua/handle/KhPI-Press/22736.

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Дисертація на здобуття наукового ступеня кандидата технічних наук за спеціальністю 05.22.09 – електротранспорт; Національний технічний університет "Харківський політехнічний інститут", 2016 р. Вирішена науково-практична задача синтезу комбінованої електромеханічної та пневматичної системи нахилу кузова швидкісного електрорухомого складу для колії 1520 мм, яка дозволила встановити оптимальні параметри лінійного двигуна та вимоги до вибору елементної бази напівпровідникового перетворювача (типи ключів та діодів), параметрів та типів балонів пневморесор. Запропоновано для нахилу кузова застосовувати комбіновану систему, що складається з лінійного двигуна і регульованого пневмопідвішування другого ступеня. Нахил кузова на кут до 5 ° забезпечується за рахунок електромеханічного приводу, що має більшу швидкодію, при великих кутах нахил проводиться за рахунок спільної дії електромеханічного і пневматичного приводів.
The thesis for granting the Degree of Candidate of Technical sciences on specialty 05.22.09 – Electric Transport. – National Technical University "Kharkiv Polytechnical Institute", 2016 Scientific and practical problem of combined electromechanical and pneumatic body tilt system of high-speed rolling stock for railway gauge of 1520 mm is solved. At allowed to determine optimum parameters of linear motor and requirements to select elementary base for semiconductor transformer (variations of keys and diodes), parameters and types of air springs tanks is well is to define with the loads on rolling stock components of structure mounted on bodies. It is offered to use body tilt combined system which is made up of linear motor and controlled pneumatic hanging of the second the level. Body tilt by the angle up to 5° is achieved by means of electro-mechanical drive possessing joint action. At great angles tilt is realized at the expense of electromechanical and pneumatic drive joint action.

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Єріцян, Багіш Хачикович. "Синтез комбінованої системи нахилу кузова швидкісного електричного рухомого складу." Thesis, НТУ "ХПІ", 2016. http://repository.kpi.kharkov.ua/handle/KhPI-Press/22716.

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Дисертація на здобуття наукового ступеня кандидата технічних наук за спеціальністю 05.22.09 – електротранспорт; Національний технічний університет "Харківський політехнічний інститут", 2016 р. Вирішена науково-практична задача синтезу комбінованої електромеханічної та пневматичної системи нахилу кузова швидкісного електрорухомого складу для колії 1520 мм, яка дозволила встановити оптимальні параметри лінійного двигуна та вимоги до вибору елементної бази напівпровідникового перетворювача (типи ключів та діодів), параметрів та типів балонів пневморесор. Запропоновано для нахилу кузова застосовувати комбіновану систему, що складається з лінійного двигуна і регульованого пневмопідвішування другого ступеня. Нахил кузова на кут до 5 ° забезпечується за рахунок електромеханічного приводу, що має більшу швидкодію, при великих кутах нахил проводиться за рахунок спільної дії електромеханічного і пневматичного приводів.
The thesis for granting the Degree of Candidate of Technical sciences on specialty 05.22.09 – Electric Transport. – National Technical University "Kharkiv Polytechnical Institute", 2016 Scientific and practical problem of combined electromechanical and pneumatic body tilt system of high-speed rolling stock for railway gauge of 1520 mm is solved. At allowed to determine optimum parameters of linear motor and requirements to select elementary base for semiconductor transformer (variations of keys and diodes), parameters and types of air springs tanks is well is to define with the loads on rolling stock components of structure mounted on bodies. It is offered to use body tilt combined system which is made up of linear motor and controlled pneumatic hanging of the second the level. Body tilt by the angle up to 5° is achieved by means of electro-mechanical drive possessing joint action. At great angles tilt is realized at the expense of electromechanical and pneumatic drive joint action.

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23

Allgeuer, Philipp [Verfasser]. "Analytic Bipedal Walking with Fused Angles and Corrective Actions in the Tilt Phase Space / Philipp Allgeuer." Bonn : Universitäts- und Landesbibliothek Bonn, 2020. http://d-nb.info/1224966252/34.

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24

Liu, Mingyi. "Energy Harvesting from the Human Body for Wearable and Mobile Devices." Diss., Virginia Tech, 2020. http://hdl.handle.net/10919/99305.

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Wearable and mobile devices are an important part of our daily life. Most of those devices are powered by batteries. The limited life span of batteries constitutes a limitation, especially in a multiple-day expedition, where electrical power can not access conveniently. At the same time, there is a huge amount of energy stored in the human body. While walking, there is a large amount of power dissipated in the human body as negative muscle work and the energy loss by impact. By sourcing locally and using locally, human body energy harvesting is a promising solution. This dissertation focuses on harvesting energy from the human body to power wearable and mobile devices while poses a minimum burden on the human body. Three topics related to the human body energy harvesting are explored, i.e, energy harvesting backpack, negative muscle work harvester, and energy harvesting tile/paver. The energy harvesting backpack was invented in 2006. Extensive work was done to improve the performance of backpack energy harvester. The backpack is modeled as a spring-mass-damper system. Mechanical Motion Rectifier was added to the spring-mass-damper system to increase the frequency bandwidth. A spring is added to the spring-mass-damper system, between the harvester and the backpack mass, and a inerter-based 2DOF (degree-of-freedom) backpack is created. The inerter-based 2DOF backpack improves the power output, frequency bandwidth, and power stroke ratio performance. MMR was added to the inerter-based 2DOF backpack to reduce the peak stroke. Compared with the conventional spring-mass-damper backpack, the MMR and inerter-based 2DOF backpack can harvest more power with large bandwidth at a small sacrifice of stroke. The electric damping was also tuned to increase the power output and bandwidth for the energy harvesting backpack. The negative work harvester mounts on the human ankle and harvests energy in the terminal stance phase in human walking, when the calf muscle is doing negative muscle work. This harvester is an analogy to regenerative brake in vehicles. The energy harvesting paver/tile harvests energy when the heel contacts with ground and energy are dissipated by impact.
Doctor of Philosophy
Wearable and mobile devices are an important part of our daily life. Most of those devices are powered by batteries. The limited life span of batteries constitutes a limitation, especially in a multiple-day expedition, where electrical power can not access conveniently. At the same time, there is a huge amount of energy stored in the human body. While walking, there is a large amount of power dissipated in the human body as negative muscle work and the energy loss by impact. By sourcing locally and using locally, human body energy harvesting is a promising solution. This dissertation focuses on harvesting energy from the human body to power wearable and mobile devices while poses a minimum burden on the human body. Three topics related to the human body energy harvesting are explored, i.e, energy harvesting backpack, negative muscle work harvester, and energy harvesting tile/paver. The energy harvesting backpack was invented in 2006. Extensive work was done to improve the performance of backpack energy harvester. The backpack is modeled as a spring-mass-damper system. Extensive work have been done to make the energy harvesting backpack broad frequency bandwidth. The negative work harvester mounts on the human ankle and harvests energy in the terminal stance phase in human walking. This harvester is an analogy to regenerative brake in vehicles. The energy harvesting paver/tile harvests energy when the heel contacts with ground and energy are dissipated by impact.

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Gautrey, Charlotte. "The biomechanics of the dynamic defence mechanism." Thesis, University of Hertfordshire, 2013. http://hdl.handle.net/2299/13905.

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Context: It has been suggested that muscle fatigue can lead to injury, however, research investigating this phenomenon in functional ankle instability (FAI) subjects is lacking. Aim: The purpose of this thesis was to research postural sway and muscular latency in FAI subjects and healthy controls, both before and immediately after localised and globalised fatigue protocols. Subjects: All subjects used in this project were males, between the ages of 18 and 25 years, and participated in regular (>2 x week) aerobic exercise. Subjects were categorised into healthy subjects, or subjects with a history of FAI using the FAI questionnaire. Methods: Neuromuscular control was analysed in FAI subjects and healthy controls through measures of muscular latency and postural sway. These measures were repeated both before and immediately after localised and globalised fatigue protocols. Results: The induction of localised and globalised fatigue had no effect on muscle latency in the FAI or healthy subjects. However, postural sway was significantly increased in the FAI subjects, following localised and globalised fatigue, with globalised fatigue also significantly increasing postural sway in the healthy subjects. The globalised football-specific fatigue protocol caused the greatest deficits in the FAI subjects, but also the healthy controls. Conclusions: In terms of muscle latency individuals that participate in sports, as well as sports clinicians and coaches, should not be concerned about the theorised relationship between the onset of fatigue and an increased injury risk at the ankle. However, in terms of postural sway the globalised football-specific fatigue protocol caused the greatest deficits. This highlights that the fatigued individual may be at greater risk of musculoskeletal injury during prolonged exercise that involves multiple joints, such as a football match.

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26

Abdallah, Wissam. "Det sistakorståget: Operation Barbarossa : En historiografisk studie om orsakerna till den tyska invasionen av Sovjetunionen." Thesis, Umeå universitet, Institutionen för idé- och samhällsstudier, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-136104.

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Eriksson, Emil, and Jakob Geholm. "Fotledskinematik vid enbenslängdhopp efter främre korsbandsskada : En jämförelse med knäfriska kontroller." Thesis, Umeå universitet, Avdelningen för fysioterapi, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-178715.

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IntroduktionFrämre korsbandsskador (ACL-skador) leder till nedsatt knäfunktion och är en stor bidragande orsak till att de ACL-skadade slutar med sin idrott. Detta kan delvis förklaras av nya rörelsestrategiser som används för att minska belastning på den skadade knäleden. Få studier har dock undersökt fotisättningens betydelse för rörelsestrategier vid hopptester. Syftet med denna studie var att undersöka fotisättning vid enbenslängdhopp efter ACL-skada i jämförelse med elitatleter och kontroller. Sekundärt syfte var att undersöka samband mellan fotisättning och självskattad knäfunktion samt rörelserädsla. MetodStudipopulationen bestod av kvinnliga deltagare i åldrarna 17-34år (medel 22.8, SD 3.87) uppdelat i tre grupper, ACL-grupp (n=28), knäfriska elitatleter (n=19) samt knäfriska kontroller (n=19). Data bestod av kinematik för fotleden, knäleden och bålen under landningsfasen vid ett enbenslängdhopp samt svar från Tampa scale for kinesiophobia och Lysholm knee scoring scale. Rörelser registrerades med ett 3D-motion capture system med åtta kameror (Oqus 300, Qualisys AB, Göteborg, Sverige). Data processerades och kalkylerades med programvaran Qualisys Track Manager (v.2.2, Qualisys AB, Göteborg, Sverige) och Visual3D. ResultatStudien fann inga signifikanta skillnader mellan grupperna i fotisättningens gradantal (p=0.653). Däremot sågs en signifikant skillnad i frekvens av hälisättning, helfot eller framfot där användning av framfot som landningsstrategi var dominerande hos samtliga grupper (p<0.001). Ett signifikant samband fanns mellan längre hopplängd och en mer dorsalflekterad fotisättning. (p=0.005, r=0.327). Inget samband sågs mellan självskattad rörelserädsla/knäfunktion och fotisättning efter ett enbenslängdhopp. KonklusionStudien fann inga kompensatoriska rörelsestrategier hos personer med skadat ACL i jämförelse med elitatleter och kontroller med friska knän. Framfot var dominerande landningsstrategi hos alla grupper vid enbenslängdhopp med en tendens till mindre vinkel i plantarflexion hos ACL-skadade. Rörelserädsla och knäfunktion verkar inte påverka fotisättning vid enbenslängdhopp.

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Jansson, Maria, Angelica Todoran, and Malm Maria Saleh. "En jämförelse mellan regelverken K2 och K3 : Vilka orsaker ligger till grund för valet av regelverk hos företag?" Thesis, Högskolan i Borås, Akademin för textil, teknik och ekonomi, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-21617.

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Bokföringsnämnden (BFN), som ansvarar för utvecklingen av god redovisningssed, startade år 2004 K-projektet som innefattar allmänna råd indelade i fyra kategorier av regelverk; K1, K2, K3 och K4. Regelverken syftar till att tillhandahålla företag ett enhetligt regelverk att följa. K3 är huvudregelverket, men mindre företag, vilka inte uppfyller gränsvärdena för att klassificeras som ett större företag, kan välja att tillämpa K2 för sin redovisning (BFN 2017d). K3 är utformat ur ett användarperspektiv, vilket innebär att det innehåller fler redovisningsalternativ för att ge användare ett relevant underlag inför finansiella beslut. K2, vars syfte är att förenkla upprättandet av redovisningen, är istället tänkt att ge en tillförlitlig bild av företagets ekonomi. Enkelheten i K2 kommer från att det är regelbaserat och därmed har klara direktiv att följa, vilket skiljer sig från K3 som är ett principbaserat regelverk och på så vis kräver en mer professionell bedömning hos upprättaren (Norberg 2014; SRF konsulterna 2019). Med detta som utgångspunkt är syftet med studien att undersöka vilka orsaker som ligger bakom företags val mellan regelverken K2 och K3. För att uppnå detta syfte har vi med tillämpning av flerfallsstudier genomfört kvalitativa semistrukturerade intervjuer med fyra mindre företag samt en revisor. Vi mottog även mailsvar på intervjufrågorna från ett företag och en revisor. Vi har haft en induktiv ansats och insamlat data för att generera resultat som kan bidra till teoretisk förståelse i ämnet. Studiens resultat visar att det finns redovisningsskillnader som i viss mån påverkar företags val mellan K2 och K3, men det har även framkommit att krav från moderbolag har ett inflytande i valet. Företag har överlag inte tillräckliga kunskaper för att själva avgöra vilket regelverk som passar dem bäst och därmed förlitar de sig i hög grad på revisorer. Utifrån studiens resultat har vi därför fått skifta vårt fokus till att istället diskutera hur den kontinentala och anglosaxiska traditionen har påverkat utformningen av K-regelverken.
The Swedish Standards Accounting Board, which is responsible for the development of generally accepted accounting principles, started the K-project in 2004, which includes general advice divided into four categories of regulatory framework; K1, K2, K3 and K4. The regulations aim to provide companies with a uniform set of rules to comply with. K3 is the main regulation, but smaller companies, which do not meet the limit values for being classified as a larger company, can choose to apply K2 for their accounting (BFN 2017d).K3 is designed from a user perspective, which means that it contains more accounting options to provide users with a relevant basis for financial decisions. K2, whose purpose is to simplify the preparation of the accounts, is, on the other hand, intended to provide a reliable picture of the company's finances. The simplicity of K2 comes from the fact that it is rule-based and thus have clear directives to follow, unlike K3 which is a principle-based regulatory framework and in some cases requires a more professional assessment by the author (Norberg 2014; SRF konsulterna 2019).With this as a starting point, the purpose of the study is to investigate the causes behind companies' choice between these regulations. With the help of multiple case studies, we have carried out qualitative semi-structured interviews with four small companies and one auditor, in order to achieve our goal. We also received mail responses to the interview questions from one company and one auditor. We have had an inductive approach and collected data to generate results that can contribute to theoretical understanding of the subject. The results of the study show that there are accounting differences that to a certain extent affect companies' choice between K2 and K3, but it has also appeared that claims from the parent company have an influence in the choice. Companies generally do not have sufficient knowledge to decide for themselves which regulation is best suited to them and thus rely heavily on the auditors. Based on the study's results, therefore, we have shifted our focus to instead touching on how the Continental and Anglo-Saxon tradition have influenced the design of the K-regulations. This study is written in Swedish.

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Persson, Eva. "Färgkodning för ett självständigt liv : Wayshowing för personer med demenssjukdom." Thesis, Mälardalens högskola, Akademin för innovation, design och teknik, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-12972.

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I denna rapport beskriver jag hur jag tagit mig an ett rumslig informationsproblem som grundar sig i personer med demenssjukdoms mentala förmåga att orientera sig. Min bakgrund som undersköterska i kombination med min kunskap i hur rum påverkar människans beteende gör att jag reagerat på de miljöer där dessa personer vistas. Studien är genomförd på Marielunds äldreboende och seniorboende i Eskilstuna kommun och syftar till att främja de boendes självständighet.Resultatet visar arkitekturens komplexitet och observationen av boendet avslöjar en mängd rumsliga hinder som påverkar orienterbarheten negativt för personer med demenssjukdom. Utifrån teorier om hur vi människor orienterar oss och hur demenssjukdom påverkar den kognitiva förmågan har ett gestaltningsförslag på ett vägledningssystem tagits fram. Forskningen visar på behovet av anpassning av boendemiljöer för personer med demenssjukdom och att en medveten färgsättning kan hjälpa dessa personer till ett mer självständigt liv. Vägledningssystemet är designat för att leda betraktaren med hjälp av referenspunkter i form av färgkodade väggmoduler och ledtrådar i form av linjer i golvet. Slutsatserna av studien visar att en tydligare översikt av miljön och visuella hjälpmedel kan göra så att de boende klarar sig bättre själv vilket i sin tur gör att de kan bo kvar hemma längre.
This report describes how I have engaged a spatial information problem based in the cognitive ability of people with dementia and their ability to orient themselves. My academic knowledge of how space affects people’s behavior in combination with my experience as a secondary nurse have made me react to the environments in which these people reside. The study was conducted at Marielunds nursing home and senior housing in the city of Eskilstuna and aims to encourage residents independence. The result shows the architecture’s complexity and the observation of the housing reveals a variety of spatial barriers that affect the ease of orientation negatively for people with dementia. Based on theories of how we orient ourselves and how dementia affects the cognitive ability I have developed a design proposal for a guidance system. The research demonstrates the need for adaptation of living environments for people with dementia and that a deliberate color scheme can help these people to a more independent life. The guidance system is designed to lead the viewer with reference points in the form of color-coded wall modules and visual clues in the form oflines in the floor. The findings of this study show that a more clear overview of the environmental and visual aids can help the residents to a more independent life witch will allow them to stay in their own home longer.

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Castanheiro, Dino Santos. "Tilt angle optimization for different solar models." Master's thesis, 2017. http://hdl.handle.net/10316/82956.

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Dissertação de Mestrado Integrado em Engenharia Electrotécnica e de Computadores apresentada à Faculdade de Ciências e Tecnologia
A energia solar é uma fonte de energia sustentável que pode ser usada para alimentar edifícios e indústria, sendo também benéfica para o ambiente. O fator mais importante no desempenho de um painel solar é a quantidade de radiação solar que intercepta. Portanto, é determinado o ângulo de inclinação ideal de forma a maximizar esta radiação solar intercetada.Para efetuar esta determinação, são usados vários modelos solares.Esta dissertação tem como objetivo principal calcular, para um painel solar na cidade de Coimbra, ângulos de inclinação ótimos e a energia solar máxima, o mais aproximado da realidade, usando o melhor modelo solar testado.Para isso, inicialmente, é efetuada a explicação de todos os dados solares referentes aos ângulos provenientes do sol e aos diferentes tipos de radiação. De seguida, são apresentados os modelos solares usados para calcular, através do Visual Basic for Applications, o ângulo de inclinação ideal e a energia solar máxima.São assim apresentados os resultados do ângulo de inclinação diário, mensal e anual ideais e também a energia solar mensal e anual máxima para cada modelo solar, para a cidade de Coimbra. De seguida, é realizada a comparação de resultados obtidos de forma a determinar o melhor modelo solar para calcular o ângulo de inclinação ideal e a máxima energia solar incidente mais próximos da realidade e também para determinar o melhor ajuste para um painel solar, se com um ângulo de inclinação ideal diário, mensal ou anual, tendo em conta a energia máxima intercetada e os custos com um mecanismo de seguimento.O tema desta dissertação é um assunto importante para quem quer que utilize ou que queira investir em painéis solares na cidade de Coimbra, no interesse de melhorar a relação custo-benefício do investimento realizado ou por realizar.
Solar energy is a sustainable source of energy that can be used to power building and industry while also being beneficial to the environment. The most important factor in the performance of a solar panel is the amount of solar radiation that reaches it. Thus, optimum tilt angle is determined in order to maximize this incident solar radiation. To achieve this, several solar models can be used. The objective of this dissertation is to provide, for the city of Coimbra, real-world approximate values of optimum tilt angles and maximum solar energy for a collector panel, by using the ideal solar model.For this purpose, initially, the explanation of all solar data regarding the solar angles and the different types of radiation is done. Thereafter, the solar models, which are calculated using Visual Basic for Applications regarding optimum tilt angle and maximum solar energy, are presented. Therefore, it is introduced the results of the optimum daily, monthly and annual tilt angle and also maximum monthly and annual solar radiation for each solar model, for the city of Coimbra. Thereafter, the comparison of results is done in order to determine the best model to calculate approximate real-word values of optimum tilt angle and maximum solar energy and also to determine which is the better adjustment for a collector panel, if either daily, monthly or annual, taking into account the intercepted solar energy and costs such as a tracking mechanism.The theme of this dissertation is an important issue for whoever utilizes or wants to invest in solar panels in the city of Coimbra, in the interest of improving the cost-effectiveness of the investment made or to be made.

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Yan, Chao Ping Iris. "A new angle on the tilt illusions /." 2003. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&res_dat=xri:pqdiss&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft_dat=xri:pqdiss:3108128.

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"Photovoltaic Modules: Effect of Tilt Angle on Soiling." Master's thesis, 2011. http://hdl.handle.net/2286/R.I.9511.

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abstract: Photovoltaic (PV) systems are one of the next generation's renewable energy sources for our world energy demand. PV modules are highly reliable. However, in polluted environments, over time, they will collect grime and dust. There are also limited field data studies about soiling losses on PV modules. The study showed how important it is to investigate the effect of tilt angle on soiling. The study includes two sets of mini-modules. Each set has 9 PV modules tilted at 0, 5, 10, 15, 20, 23, 30, 33 and 40°. The first set called "Cleaned" was cleaned every other day. The second set called "Soiled" was never cleaned after the first day. The short circuit current, a measure of irradiance, and module temperature was monitored and recorded every two minutes over three months (January-March 2011). The data were analyzed to investigate the effect of tilt angle on daily and monthly soiling, and hence transmitted solar insolation and energy production by PV modules. The study shows that during the period of January through March 2011 there was an average loss due to soiling of approximately 2.02% for 0° tilt angle. Modules at tilt anlges 23° and 33° also have some insolation losses but do not come close to the module at 0° tilt angle. Tilt anlge 23° has approximately 1.05% monthly insolation loss, and 33° tilt angle has an insolation loss of approximately 0.96%. The soiling effect is present at any tilt angle, but the magnitude is evident: the flatter the solar module is placed the more energy it will lose.
Dissertation/Thesis
M.S.Tech Engineering 2011

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鄭惟任. "Study on Tilt Angle Inspection with 3-Axis Accelerometer." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/vnp2wq.

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碩士
國立彰化師範大學
車輛科技研究所
106
This study aims at accomplish intelligent and high precision of the tilt angle inspection. The tilt angle inspection aims at realizing a micro-control-unit (MCU)-based tilt angle inspection system with a 3-axis accelerometer. The tilt angle conversions from 3-axis acceleration data input for micro-control-unit (MCU) with trigonometric functions and complicated mathematic calculations. The results display that on TFT-LCD can be easy for use inspection. The tilt angle inspection has automatic correction function, which it can avoid measurement error caused by incorrect employing. Use deviation method to confirm the accuracy of the measure. In addition, the measured results of tilt angles can be transmitted via the medium such as TTL.

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Yu, Hsiu-Wei, and 余修瑋. "A Tilt Angle Measurement System using RCNN Computer Vision Technique." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/35972935325899780035.

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碩士
國立中興大學
電機工程學系所
105
Taiwan is located on the circum-Pacific seismic zone and earthquakes occur quite frequently. As a result, buildings, street lights, and piles are prone to tilt because of the earthquakes. If they tilt to a certain extent, there is a high risk of collapsing. To measure the tilt angle, devices like theodolites or posting plumbs are commonly used and the process is generally expensive, time-consuming, dangerous and even stringent in mountainous terrain. Therefore, this paper introduces a relatively simple, flexible, non-contact measurement method – using devices like a smart phone with a camera and a geomagnetic sensor to estimate the tilt angle and tilt azimuth of a target so as to automatically detect potential crisis for subsequent maintenance. First, according to the projection theory, we derive formulas to estimate the tilt angle and tile azimuth by using two shootings at different positions. Specifically, we capture an image as well as the shooting azimuth at each shooting and use image processing technique to calculate the projected tilt angle in each photo. Then, we apply our formula to compute the estimated tilt angle and tilt azimuth. Moreover, we apply the Faster R-CNN target detection algorithm to identify the target and then use the HSV feature and Hough Transform to obtain projected tilt angle of the target in a complicated photo. Since the sensors are easy to be interfered with the external magnetic field, we derive a selection rule empirically and further design a rapid reinforcement method to fuse multiple estimated tilt angles and azimuths to improve the estimation accuracy.

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HE, LIAN-ZE, and 何濂澤. "Investigations of gate/n�� overlapped LDD large-tilt-angle implantation." Thesis, 1992. http://ndltd.ncl.edu.tw/handle/53459317294831429875.

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Li, Tzu-Yang. "A Visual Monitoring System Using Wide-Angle Cameras and Pan-Tilt Camera." 2004. http://www.cetd.com.tw/ec/thesisdetail.aspx?etdun=U0001-1307200409434800.

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Li, Tzu-Yang, and 李子洋. "A Visual Monitoring System Using Wide-Angle Cameras and Pan-Tilt Camera." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/86070699060278502538.

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碩士
國立臺灣大學
資訊工程學研究所
92
Visual monitoring systems will play a more and more important role in our daily life. Traditional Close Circuit Television System (CCTV) sets cameras in many key positions, and need a guard to keep an eye on the videos of those cameras. In this work, we developed a fully automatic visual monitoring system that can be set up with a simple method. Utilize the properties of the wide-angle cameras and of the pan-tilt camera (PT-camera), i.e., large view field of wide-angle cameras and high-resolution images of PT-cameras, we can design a real-time visual monitoring system having high detection rate and clear target images. Important methods used in this system include the following: (1) Camera calibration: First, we estimate the intrinsic camera parameters using a camera calibration method that require simply placing a 2D calibration plane at different positions. Then, we use a cross rig having calibration markers, each marker with known 3D position, to estimate the extrinsic parameters between cameras. (2) Moving object detection: For the wide-angle cameras, Gaussian mixture is used to update the background model in real-time, which is then used to detect objects different from the background. (3) Object tracking: For the PT-camera, we use the mean-shift algorithm to keep track of the target. (4) Face detection: A cascade of boosted classifiers, working with Haar-like features, is used to obtain fast and accurate face detection. In the experiments, we combine the detection and tracking methods together to reliably fixate the PT-camera on the object. One single person can easily set up the whole system and calibrate all cameras. Our experiments showed that, when there is only one moving object in the monitoring area, our system could track the object successfully.

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Liang, Jia-Shiung, and 梁家雄. "The research of 5-axis machining error and tool''s tilt angle." Thesis, 1997. http://ndltd.ncl.edu.tw/handle/65803884180666770328.

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Cheng, Tse-Yu, and 鄭哲宇. "Three-dimensional infrared spectrometer study the tilt angle of liquid crystal molecules." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/a29ep4.

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碩士
國立虎尾科技大學
光電與材料科技研究所
97
In recent years, liquid crystal displays (LCDs) have becoming one of the most widely used flat panel displays. Some critical parameters of the LCD, such as cell gap and molecule pretilt angle, are significantly affecting their optical properties. Therefore, it’s most important key point for measuring the tilt angle of LCDs. In this study, we provided a simple method, three-dimensional Fourier transform infrared spectroscopy (3-D FTIR), to measure the tilt angle of the liquid crystal molecules in a nematic liquid crystal (E7) cell as power applied. From the infrared spectra analysis, we found that the nitrile band for 5CB of NLC molecules array was strongly affected by external voltage. Moreover, the pretilt angles of the LC cells can be predicted by 3-D FTIR without voltage supplied. Infrared absorption in the LC cell thickness direction was enhanced but the peak in the rubbing direction was reduced after applied voltage rising. Furthermore, the tilt angles of the liquid crystal cell under different voltages possess same tendency for both Heterodyne Interferometric method and 3-D FTIR method predictions.

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CHOU, YU-HSUAN, and 周裕軒. "Study on double phase tilt plane angle multiplexing for optical image encryption." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/6rtzv9.

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碩士
國立雲林科技大學
電機工程系
107
In this thesis, we propose an optical multiplexing and encryption method, which use double phase only functions (POFs) and is based on the Fresnel transform (FrT). The target images are encrypted into two POFs are retrieved by using the Double-Random-phase retrieval algorithm. In conventional FrTs, both the POF and image reconstruction planes are parallel to each other and are perpendicular to the optical axis. We here propose a tilt Fresnel transform (TFrT), in which all the planes can be rotated. The rotation mechanism is basically divided into three types: (1) image reconstruction plane rotation, (2) POF plane rotation, and (3) image reconstruction plane rotating simultaneously with the POF plane. In our simulation results, the correlation coefficients between the reconstructed and original images fall between 0.9 and 0.96 (0.93 in average). Consider the angle sensitivity of the various plane rotation in the proposed system. Regardless of the imaging plane or the phase plane, the correlation coefficient decreases greatly when the angle is only shifted by 1°. Thus the angle sensitivity is high enough and the proposed image multiplexing and encryption system is secure as well.

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WANG, YAO-TING, and 王耀庭. "Study on single phase tilt plane angle multiplexing for optical image encryption." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/5zqf6m.

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碩士
國立雲林科技大學
電機工程系
107
This thesis proposes an angle multiplexing method for optical image reconstruction using the phase-only computer-generated hologram (POCGH) in the tilt Fresnel transform (TFrT) domain. The modified Gerchberg-Saxton algorithms based on the three types of rotation manipulation in both the hologram and reconstruction planes are used, with their corresponding TFrT parameters, to extract the phase-only functions (POFs) of the target images. All the extracted POFs are then phase-modulated and summed to obtain the final POCGH, which is capable of multiplexing and avoiding overlap of reconstructed images. The computer simulation results show that the images corresponding to the various rotation manipulations at the hologram and image reconstruction planes can be successfully restored with high correlation coefficients. Due to the encrypted nature of multiplexed images, higher system security level can be achieved as images can only be correctly displayed when all the required parameters in the TFrT are available. Finally,the angle sensitivity on the image quality for each manipulation is investigated as well.

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"Thermal Interface Material Characterization Under Thermo-mechanical Stress of Induced Angle of Tilt." Master's thesis, 2011. http://hdl.handle.net/2286/R.I.14293.

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abstract: Thermal interface materials (TIMs) are extensively used in thermal management applications especially in the microelectronics industry. With the advancement in microprocessors design and speed, the thermal management is becoming more complex. With these advancements in microelectronics, there have been parallel advancements in thermal interface materials. Given the vast number of available TIM types, selection of the material for each specific application is crucial. Most of the metrologies currently available on the market are designed to qualify TIMs between two perfectly flat surfaces, mimicking an ideal scenario. However, in realistic applications parallel surfaces may not be the case. In this study, a unique characterization method is proposed to address the need for TIMs characterization between non-parallel surfaces. Two different metrologies are custom-designed and built to measure the impact of tilt angle on the performance of TIMs. The first metrology, Angular TIM Tester, is based on the ASTM D5470 standard with flexibility to perform characterization of the sample under induced tilt angle of the rods. The second metrology, Bare Die Tilting Metrology, is designed to validate the performance of TIM under induced tilt angle between the bare die and the cooling solution in an "in-situ" package testing format. Several types of off-the-shelf thermal interface materials were tested and the results are outlined in the study. Data were collected using both metrologies for all selected materials. It was found that small tilt angles, up to 0.6°, have an impact on thermal resistance of all materials especially for in-situ testing. In addition, resistance change between 0° and the selected tilt angle was found to be in close agreement between the two metrologies for paste-based materials and phase-change material. However, a clear difference in the thermal performance of the tested materials was observed between the two metrologies for the gap filler materials.
Dissertation/Thesis
M.S. Mechanical Engineering 2011

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周鵬程. "Characterization and design guidelines of submicron LATID (LArge Tilt-angle Implanted Drain) MOS devices." Thesis, 1993. http://ndltd.ncl.edu.tw/handle/15526742661171195197.

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Chen, Yen-ming, and 陳彥名. "Study of poly-Si thin-film-transistors with large angle tilt implanted drain region." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/7k7jqk.

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碩士
國立臺灣科技大學
電子工程系
100
Polycrystalline silicon thin-film-transistors (Poly-Si TFTs) have been widely used in various applications, such as static random memories (SRAMs), photodetector amplifier, scanner, and active matrix liquid crystal displays (AMLCDs). The electron field mobility of the ploy-Si TFT is larger than that of the amorphous-Si (a-Si) TFT, allowing the integration of both active matrix and driving circuitry on the same substrate. However, the conventional self-aligned poly-si TFT induces several undesired effects in the electrical characteristics, including short-channel effect、GIDL、DIBL、kink effect and hot-carrier effect. These effects are related to the presence of high electric fields at the drain junction. Hence, the relief of the electric field near the drain region is essential. In this study, in order to improve the electrical properties of devices and process simplification, the design of new device structure and the analysis of device relative parameters are carried out via process and device simulation. Four types of TFTs with different drain structures have been examined, including the conventional single source/drain TFT, the lightly-doped- drain (LDD) TFT, the large-angle-tilt-implantation-drain (LATID) TFT, and the large-angle-tilt-implantation-after-spacer (LATIAS) TFT. For a channel length of 1.0 μm, the LATID TFT devices may suffer from source/drain punch-through, due to encroachment of dopant into the channel region. However, the LATID structure can help to reduce the electric field due to a gradual dopant distribution. Accordingly, for the TFT devices with LATID structure, a proper channel doping may be employed to suppress the punch-through without considerably enhancing the electric field near the drain region. As a result, for a channel length of 1.0 μm, the LATID TFT devices with channel doping may cause a much smaller off-state leakage current than the LDD TFT and the concentional TFT devices. On the other hand, while the device is further scaled down to 0.5 μm, the LATID TFT devices may suffer from serious source/drain punch-through. Even with the usage of channel doping, the off-state leakage is still large. By using an oxide spacer prior to LATID implantation, the dopant encroachment into the channel region may be reduced. As a result, for a channel length of 0.5 μm, the LATIAS TFT device may cause a relatively smaller off-state leakage current than the LDD TFT and the conventional TFT devices.

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Zhou, Zhi Wen, and 周志文. "An investigation of large-angle-tilt implanted drain process for improving hot carrier reliability." Thesis, 1994. http://ndltd.ncl.edu.tw/handle/74489151085029016363.

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46

Chen, Sheng-Chuan, and 陳昇權. "The calculation of object's tilt angle by using depth image and application for fall detection." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/9rg789.

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碩士
國立交通大學
電控工程研究所
105
In the recent years, with the advances in medical technology, the elderly population have grown up substantially. How to provide a safety environments for the elderly has become an important issue. And according to the statics, the injuries caused by fall is one of the main reason in the accidental injuries. In addition, some elderly people would lose the mobility and even the conscious after the fall happened, which might delay the rescue time or lead to more serious damages. Therefore, in order to provide the immediately rescue when the accident fall occurs, so we proposed a novel method for pedestrian fall detection. In our research, we adopt the depth-camera to capture the data of depth, and use the least-square method to calculate the tilt angle of pedestrian. Then, we could implement the method to the fall detection system. Finally, the effectiveness of the fall detection have been verified.

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Wang, Chen-Chen, and 王珍珍. "Control of liquid crystal pre-tilt angle using mixed polyimide alignment layer and its application." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/00734457308891935852.

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碩士
國立成功大學
光電科學與工程研究所
96
Three approaches to control liquid crystal (LC) pre-tilt angle in a cell are demonstrated using a polyimide (PI) alignment layer coated on substrates, which is a mixture of horizontal (H) and vertical alignment (V) polyimides. The concentration ratio of H- to V-PI, baking temperature, and rubbing strength are found to affect the pre-tilt angle, and provide us the parameters to control the pre-tilt angle of a LC cell. Experimentally, the pre-tilt angles ranging from ~ 15o to 85o are achieved. Using the developed technique, we then fabricate a polarization converter, which allows us to change the polarization of an incident polarized light continuously depending on the beam position in the cell. Finally, optically compensated birefringence (OCB) cells with various pre-tilt angles are fabricated. Their electro-optical characteristics are measured. We demonstrate an un-biased OCB cell having a high pre-tilt angle (~50o) achieved using the technique developed in the present work; i.e. its initial state is stable in the bend I state without applying a bias voltage. In addition, we observe that a transient state forms during suddenly turning on the voltage applied to a low-pretilt-angle OCB cell at the splay state. It is found that the OCB cell does not transit from the splay state to the bend I state directly. Notably, the technique developed in this thesis utilizes a conventional rubbing machine and mixture of commercial PIs. Thus, it is compatible with the existing manufacturing processes, and possesses high potential for practical application.

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48

Chang, Yu-Chiao, and 張宥喬. "Investigating human performance on large Touchscreen :The effect of tilt angle, icon location and icon size." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/41073103366038098879.

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碩士
實踐大學
產品與建築設計研究所碩士在職專班
100
Touch manipulation became a core trend of next technology generation. It is beneficial to user if better touch interface was presented. To discuss this latest trend, this research reviewed literature from technology, industry, and user behavior. In order to understand manipulate performance, there were two experiments conducted in this research. Investigating how the tile angle, icon location, and icon size could affect the human performance in large touch screen. Questionnaire was used to value the user perspective. Statistical analysis was applied to provide a suitable standard to evaluate touch manipulate and adjust the user interface. There were two experiments in this research, using 27” touch display to investigate how display tile angle, icon location, and icon size affect the human manipulate performance. Experiment A was focused on three independent variables: (1) the icon location in the center and corner of screen. (2) Tile angle. (3) Icon size, to observe the user performance. By experiment and the questionnaire, there are three results: (1) The display tile angle is significantly affected the manipulation performance. The mean finished time of 200 tile angle was 35.36 ms fewer than 600 tile angle. (2) Finished time is shorter when the icon is bigger in the screen. When designing the icon, 69-92 pixels were suggested. Between these ranges, user could achieve the best performance, and also the interface was not over occupied. (3) User touch point variation was fewer when the target was in the middle of the screen, while variation was larger when target is in the corner area. Depend on the icon location; touch point variation showed some degree of the direction. Experiment 2 further discussed location touch test in certain scenario such as the 4 corners, icon size and the tilt angle. Basically, this experiment was attempted to find the best performance and make the guideline for designer. By experiment and the questionnaire, there are two results: (1) Observing the corner of screen, participants’ finished tine is shorter when the icon is bigger, but this phenomeono become obscure since 69* 69 pixels. (2) Comparing the corner area of screen, for the right side of screen, the average performance is better than the left side. No matter the finished time, the hallo effect, and the touch point variation are all performance better in right side of scrren. However the finished time decrease more slower when the icon size become bigger. This situation is not obvious for the right side of screen. (3) The pointing difficulty would increase when the icon is at the corner of screen. The finished time and the point variation would all affected by these location, but not the correct rate. The main results of the research are as below: (1) For touch display, the suitable icon size is between 69-92 pixels for different tile angle usage situation. Between these ranges, user could achieve the best performance, and also the interface was not over occupied. (2) No matter under which kind of manipulate situation, touch point variation was towered the center of screen. In order to enhance the user performance, the active area of touch display and the hallo effect area should be corrected tower the center of screen, (3) When the user manipulate the touch display, although the icon size is small, the finished time in the center of screen (350 mm * 120mm) is still better than the finished time of corner area. In order to achieve cost effective, target size in the center of screen can be reduced without side effect. (4) Target around 4 corners required longer response time; however, it would not affect operation correctness and click variation. Important message was suggested to place in the corner. In sum, this research provides the guideline for designing suitable icon in the big touch screen.

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Lin, Yan-Nan, and 林彥男. "Optical design of new pickup head and applied in the measurement of tilt angle and displacement." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/94129030783294723725.

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博士
國立中央大學
光電科學研究所
100
This thesis investigates the optical design of a new pickup head and its application for the measurements of tilt angle and displacement. The main content of this study can be separated into three parts. Part I describes the optical design for a unitary photo detector and single-path combo optical pickup head. Part II discusses the optical design and evaluation of the optical pickup head with a laser expander for determining tilt angle and displacement. Part III discusses further research related to the evaluation of multi-directional azimuth and tilt angles by a DVD OPH with a CMOS sensor. In the part I, we presented a compact design for a unitary photo detector and single-path combo optical pickup head (called the combo-OPH) which can be used for Blu-ray Disc (BD), digital versatile disc (DVD) and compact disc (CD) systems. The number of components in the OPH design can be reduced by focusing three discrete wavelength laser beams on a photo detector. The three laser diode chips and a photo detector can be encapsulated within an integrated optical unit (IOU), which is then combined with a compensator and rhomboid beam-splitter prism. The blazed holographic optical elements are designed so as to concentrate the diffracted light power to the 0th-order and the 1st-order and to improve the round-trip efficiency. The simulation results, including the S-curve and optical efficiency, are compared for this combo-OPH with three IOUs. The optical efficiency of the proposed OPH for BD/ DVD/ CD systems as detected by the photo detector are 5.545 %, 3.889 %, and 3.517 %, respectively. Our design results show that the combo-OPH with one IOU performs better than the combo-OPH with three IOUs. In part II, an optical design is developed for a Blu-ray OPH with a laser expander that can synchronously detect the linear vertical displacement and tilt angle of the test plane. To improve the signal accuracy of the photo detector, a laser expander is used to transform the shape of the laser beam from elliptical to circular. A quadrant photo detector as used to detect the relative relationship between the VA, VB, VC, VD signals, and can be used to measure the tilt angle and displacement at the test plane. Measurement detection and analysis is based on one normalized focusing error signal (NFES) and two angular signals. The optical efficiency of the Blu-ray OPH with laser expander is 59.29 %. The optical efficiency of the currently used commercial OPH is only 8.08 %. The higher optical efficiency of an OPH makes it easier to distinguish between signal and noise at the photo detector. In part III, we present a new detection method for an improved DVD OPH system capable of measuring multi-directional azimuth and small tilt angles. A complementary metal-oxide semiconductor (CMOS) sensor is used to capture images and analyze the slight shift of the central position of the beam shape when the test plane rotates at a tilt angle to produce an angular signal. The proposed detection method can determine the azimuth angle of the test plane from 0° to 360° at intervals of 5°. The elevation angle measurements vary from 0° to 4.2° at intervals of 0.3°. The simulation results show that the improved DVD pickup head system can recognize multi-directional azimuth angles of the test plane under a small tilt. Finally, we determine that the resolutions for the elevation and azimuth angles in the proposed system are 0.28° and 4.60°, respectively. Using a smaller pixel size for the CMOS sensor or smaller numerical aperture of the focusing lens (NAf) would help to improve the resolution for 2D angular measurement.

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"Seasonal and Tilt Angle Dependence of Soiling Loss Factor and Development of Artificial Soil Deposition Chamber Replicating Natural Dew Cycle." Master's thesis, 2017. http://hdl.handle.net/2286/R.I.45024.

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abstract: This is a two-part thesis. Part 1 presents the seasonal and tilt angle dependence of soiling loss factor of photovoltaic (PV) modules over two years for Mesa, Arizona (a desert climatic condition). Part 2 presents the development of an indoor artificial soil deposition chamber replicating natural dew cycle. Several environmental factors affect the performance of PV systems including soiling. Soiling on PV modules results in a decrease of sunlight reaching the solar cell, thereby reducing the current and power output. Dust particles, air pollution particles, pollen, bird droppings and other industrial airborne particles are some natural sources that cause soiling. The dust particles vary from one location to the other in terms of particle size, color, and chemical composition. The thickness and properties of the soil layer determine the optical path of light through the soil/glass interface. Soil accumulation on the glass surface is also influenced by environmental factors such as dew, wind speeds and rainfall. Studies have shown that soil deposition is closely related to tilt angle and exposure period before a rain event. The first part of this thesis analyzes the reduction in irradiance transmitted to a solar cell through the air/soil/glass in comparison to a clean cell (air/glass interface). A time series representation is used to compare seasonal soiling loss factors for two consecutive years (2014-2016). The effect of tilt angle and rain events on these losses are extensively analyzed. Since soiling is a significant field issue, there is a growing need to address the problem, and several companies have come up with solutions such as anti-soiling coatings, automated cleaning systems etc. To test and validate the effectiveness of these anti-soiling coating technologies, various research institutes around the world are working on the design and development of artificial indoor soiling chambers to replicate the natural process in the field. The second part of this thesis work deals with the design and development of an indoor artificial soiling chamber that replicates natural soil deposition process in the field.
Dissertation/Thesis
Masters Thesis Engineering 2017

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Dissertations / Theses on the topic 'Angle de tilt'

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