Tesis sobre el tema "Mechanical stre"
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DE, ZIO Elena. "The responses of poplar plants to mechanical bending stress". Doctoral thesis, Università degli studi del Molise, 2017. http://hdl.handle.net/11695/82358.
Texto completoMechanical stress is a common environmental perturbation that can considerably affect plant stability. In the course of evolution, plants evolved different mechanisms for coping with and mitigating the negative effects of this disadvantageous abiotic stress. Study the impact of this stress on the woody plant means to provide a scientific basis in the knowledge of the root biology and complex dynamics of the reaction wood formation, important in the context of plant productivity and utilization. In this thesis, a controlled simulation of mechanical stress was performed in Populus nigra roots by using a simple experimental system. After giving an outline of the molecular mechanisms that regulate the responses to long-term bending stress between the two sides of the poplar root (the convex and the concave side), this thesis lays emphasis on the roles of main plant hormones in the stress-induced reaction wood formation. Using the method based on liquid chromatography coupled to tandem mass spectrometry analysis (LC-MS/MS) auxins, abscisic acid and cytokinins profiling was obtained for different sectors and sides of the bent root and stem, subjected to different intensities of tension and compression forces. Data obtained were then compared in order to verify similarities and differences between root and stem response to bending. In order to better understand the role of hormones in the induction of cambial zone of poplar root subjected to bending, a method for isolation of cambial tissue was developed and the analysis of auxins, abscisic acid and cytokinins profile was carried out. Taking together, data of this thesis showed as poplar root responds to bending producing in the concave zone a compression wood, rich in lignin content, with features similar to the compression wood produced at stem level by gymnosperms. A high level of auxin and abscisic acid seems to accompany this development process, even in the early phases of the treatment.
Lahoori, Mojdeh. "Thermo-hydro-mechanical behavior of an embankment to store thermal energy". Electronic Thesis or Diss., Université de Lorraine, 2020. http://www.theses.fr/2020LORR0252.
Texto completoNowadays, thermal energy storage in geostructures like embankments can be possible by installing the horizontal heat exchangers in different layers of compacted soil. In this system, the thermal energy is stored in summer via a fluid, circulating in the heat exchangers, to be extracted in the demand period. When the serviceability of embankment as a medium to store the thermal energy starts, the compacted soil will be subjected to the daily and seasonally temperature variations. These seasonal temperature variations could modify the thermo-hydro-mechanical performance of the compacted soil. Thus, the aim of this study is to investigate the thermal and mechanical performances of a compacted soil when it is subjected to monotonic and cyclic temperature variations. The studied soil is a sandy lean clay that is frequently used in embankment constructions in France. The thermal and mechanical behavior of the soil are investigated at a compaction state corresponding to the optimal thermal properties. However, this compacted soil is unsaturated and the estimation of its thermal properties is complex. In this study, an inverse analytical model is proposed to estimate the thermal properties of the soil using temperature monitoring in the range of 20 to 50 °C in a soil compacted in a large container. The estimated thermal parameters were compared to classical laboratory measurements (transient and steady-state methods). The comparison showed that the estimated values were close to the results obtained in transient laboratory method. Using this method, the thermal efficiency of the compacted soil can be verified in the lifetime of the storage system. To ensure the structure stability, long-term mechanical response of these systems subjected to monotonic and cyclic temperature variations should be investigated. To achieve this aim, using temperature-controlled oedometric and direct shear devices, consolidation and shear parameters of the studied soil at different monotonic (5, 20, and 50 °C) and cyclic (5 to 50 °C) temperatures were investigated. The results of temperature-controlled oedometric tests showed that the effect of the temperature variation is more pronounced under vertical pressures higher than the preconsolidation pressure. The compression and swelling indexes could be considered independent of temperature variations. Therefore, the overall settlement of the embankment due to thermal variation near the heat exchangers could be considered negligible. The results of temperature-controlled direct shear tests showed that the temperature variations (monotonic heating or cooling, or temperature cycles) increased the cohesion which is beneficial for the bearing capacity and slope stability of embankments. These results can be directly used in the design of embankments to store thermal energy exposed to similar thermo-mechanical paths. Finally, the thermal performance of the compacted soil is verified using a numerical simulation considering the soil atmosphere interaction. Different depths installation of heat exchanger loops and different heat storage scenarios were simulated. The results showed that the compacted soil increases 8.5% the systems performance compared to the horizontal loop installation in the local soil. The results of two different scenarios show that an inlet fluid temperature of 50 °C in summer increases highly the system performance (13.7% to 41.4%) while the improvement is less significant (0% to 4.8%) for the ambient inlet temperature. Moreover, a deeper installation of horizontal loops increases the system performance. From the numerical simulation results can be concealed that the embankment is in interaction with the atmosphere from its upper and lateral surfaces, the thermal efficiency of the structure could be affected due to heat losses. Therefore, it is preferable to place the heat exchangers away from the top and side surfaces
LIONETTI, MARIA CHIARA. "LAMINOPATHIES: PATHOLOGY, CELL MECHANICS ANDENVIRONMENTAL INDUCTION". Doctoral thesis, Università degli Studi di Milano, 2019. http://hdl.handle.net/2434/620532.
Texto completoABSTRACT The nuclear lamina (NL) is a fibrillary protein network lining the inner surface of the nuclear envelope. It is mainly composed by type V intermediate filaments called lamins and lamin-associated proteins. Three lamin genes are present in Mammals: LMNA, which encodes lamin A and lamin C (Atype lamins), as well as, LMNB1 and LMNB2 that encode lamin B1 and B2 (B-type lamins) respectively. Lamins and LAPs associate to form a dense and dynamic three-dimensional matrix that establishes a huge number of stable and transient interactions with different classes of molecules: DNA, transcription factors, nuclear pore complexes and structural proteins of the cytoskeleton. All of these interactions are essential to provide nuclear structural stability and integrity, to physically and functionally link nuclear lamina to the cytoskeleton and to organizes chromatin. Thus NL, in addition to play a fundamental structural role, it is also a key player in cellular mechanotransduction processes and gene expression and epigenetic regulation. Mutations in genes encoding for lamins are associated with a wide a range of diseases, named laminopathies. Among these, the most interesting one is Hutchison-Gilford Progeria Syndrome (HGPS), a rare fatal genetic disorder due to do a point mutation in LMNA. This mutation results in the production of a truncated version of lamina A, lacking 50 amino acids, known as Progerin. HGPS is mainly characterized by morphological changes in the nucleus and premature aging. HGPS patients indeed, from their first years of life, develop pathological conditions typical of the elderly such as cataracts, diabetes and osteoporosis while preserving the normal cognitive functions. These patients typically die from cardiovascular complications around 14 years of age, on average. Considering Hutchinson-Guilford Progeria Syndrome as an extreme example of what nuclear lamina aberration entails, during my PhD I investigated many aspects of nuclear lamina biology with particular regard to the impact of nuclear lamina structural perturbations on cell functions, mechanics, gene expression regulation and the interconnection existing between nuclear lamina integrity, ageing process and oxidative stress. Indeed, to gain a comprehensive picture of nuclear lamina biology in health and disease, it has been adopted interdisciplinary and integrative research strategies able to take into account structural, mechanical and molecular aspects. Bioinformatics study has been performed: public available transcriptomic data of HGPS patients have been analysed with respect of those of healthy matched controls. This analysis allowed to delineate the typical global gene expression profile of HGPS patients and to identify all the deregulated pathways in the presence of the pathology. Moreover, impacts of lamina alterations on its physical and functional connections with extra-nuclear and nuclear elements have been studied in an inducible expression cellular model of the mutated form of Lamin A responsible for HGPS. This cellular model faithfully recapitulates the peculiar cellular phenotype of the HGPS patients resulting to be a valid alternative to primary cell lines deriving from the patients.Finally, the interdependence between oxidative stress, ageing and lamins has been investigated in a novel oxidative stress cellular model developed in our laboratory, that is also efficient in recapitulating typical ageing profile.
Ozyuksel, Alaettin Arda. "Development Of Sled Range Test Facility For Store Separation Model". Master's thesis, METU, 2007. http://etd.lib.metu.edu.tr/upload/3/12608508/index.pdf.
Texto completoKrishna, Jayanth. "Fatigue properties of Laser Powder Bed Fusion (LPBF) built 21-6-9 stainless stee". Thesis, Högskolan Väst, Avdelningen för avverkande och additativa tillverkningsprocesser (AAT), 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:hv:diva-16788.
Texto completoBankston, Susan D. "Improving the consumer demand forecast to generate more accurate suggested orders at the store-item level". Thesis, Massachusetts Institute of Technology, 2008. http://hdl.handle.net/1721.1/43829.
Texto completoIncludes bibliographical references (p. 57).
One of the biggest opportunities for this consumer goods company today is reducing retail stockouts at its Direct Store Delivery (DSD) customers via pre-selling, which represents approximately 70% of the company's total sales volume. But reducing retail stock-outs is becoming constantly more challenging with an ever-burgeoning number of SKUs due to new product introductions and packaging innovations. The main tool this consumer goods company uses to combat retail stock-outs is the pre-sell handheld, which the company provides to all field sales reps. The handheld runs proprietary software developed by this consumer goods company that creates suggested orders based on a number of factors including: * Baseline forecast (specific to store-item combination) * Seasonality effects (i.e., higher demand for products during particular seasons) * Promotional effects (i.e., lift created from sale prices) * Presence of in-store displays (i.e., more space for product than just shelf space) * Weekday effects (i.e., selling more on weekends when most people shop) * Holiday effects (i.e., higher demand for products at holidays) * Inventory levels on the shelves and in the back room * In-transit orders (i.e., orders that may already be on their way to the customer) The more accurate that the suggested orders are, the fewer retail stock-outs will occur. This project seeks to increase the accuracy of the consumer demand forecast, and ultimately the suggested orders, by improving the baseline forecast and accounting for the effect of cannibalization on demand.
by Susan D. Bankston.
S.M.
M.B.A.
Almehmadi, Fahad. "Technology to Address Food Deserts: Hybrid Application of Combined Heat And Power Assisted by Solar Dehumidification for Corner Store Groceries". University of Dayton / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1605543916479185.
Texto completoSpjutare, Christian. "Aerodynamic Loads on External Stores - Saab 39 Gripen : Evaluation of CFD methods for estimating loads on external stores". Thesis, Linköping University, Applied Thermodynamics and Fluid Mechanics, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-54127.
Texto completoExternal stores mounted on aircraft generate loads which need to be estimated before first takeoff. These loads can be measured in a wind tunnel but since the possible store configurations are basically endless, testing them all is neither economically feasible nor time efficient. Thus, scaling based on geometrical similarity is used. This can, however, be a crude method. Stores with similar geometrical properties can still behave in different ways due to aerodynamic interference caused by adjacent surfaces.
To improve the scaling performance, this work focuses on investigating two CFD codes, ADAPDT and Edge. The CFD simulations are used to derive the difference in aerodynamic coefficients, or the Δ-effect, between a reference store and the new untested store. The Δ-effect is then applied to an existing wind tunnel measurement of the reference store, yielding an estimation of the aerodynamic properties for the new store.
The results show that ADAPDT, using a coarse geometry representation, has large difficulties predicting the new store properties, even for a very simple store configuration on the aircraft. Therefore it is not suited to use as a scaling tool in its present condition. Edge on the other hand uses a more precise geometry representation and proves to deliver good estimations of the new store load behavior. Results are well balanced and mainly conservative. Some further work is needed to verify the performance but Edge is the recommended tool for scaling.
Martins, Neto Jos? Ant?nio. "Desempenho mec?nico de comp?sitos h?bridos de fibras naturais e poli?ster n?o saturado". Universidade Federal do Rio Grande do Norte, 2010. http://repositorio.ufrn.br:8080/jspui/handle/123456789/15630.
Texto completoWith the objective to promote sustainable development, the fibres found in nature in abundance, which are biodegradable, of low cost in comparison to synthetic fibres are being used in the manufacture of composites. The mechanical behavior of the curau? and pineapple leaf fibre (PALF) composites in different proportions, 25% x 75% (P1), 50% x 50% (P2) e 75% x 25% (P3) were respectively studied, being initially treated with a 2% aqueous solution of sodium hydroxide. Mechanical analyses indicated that with respect to studies of traction, for the combination of P1 and P3, better results of 22.17 MPa and 16.98 MPa, were obtained respectively, which are higher than that of the combination P2. The results of the same pattern were obtained for analysis of bending resistance where P1 is 1.21% and P3 represents 0.96%. In the case of resistance to bending, best results were obtained for the combination P1 at 49.07 MPa. However, when Young's modulus values were calculated, the values were different to the pattern of the results of other tests, where the combination P2 with the value of 4.06 GPa is greater than the other combinations. This shows that the PALF had a greater influence in relation to curau? fibre. The analysis of the results generally shows that in combinations of two vegetable fibers of cellulosic origin, the fiber which shows higher percentage (75%) is the best option than to the composition of 50%/50%. In the meantime, according to the results obtained in this study, in the case where the application should withstand bending loads, the better composition would be 50%/50%
Com o objetivo de promover o desenvolvimento sustent?vel, as fibras encontradas em abund?ncia na natureza, que s?o biodegrad?veis e de baixo custo quando comparado com as fibras sint?ticas, vem sendo utilizadas na aplica??o de produ??o de comp?sitos. Neste trabalho foi analisado o comportamento mec?nico ? partir do ensaio de tra??o e flex?o, em um comp?sito h?brido tendo como matriz uma resina sint?tica ortoft?lica refor?ada com fibras de curau? e fibras da folha de abacaxizeiro (PALF), nas propor??es de 25% x 75% (P1), 50% x 50% (P2) e 75% x 25% (P3), respectivamente, com as fibras de curau? e as fibras da folha do abacaxizeiro sendo tratadas quimicamente por uma solu??o aquosa de hidr?xido de s?dio (NaOH) com 8% de concentra??o. As an?lises mec?nicas indicaram que com rela??o aos estudos de tra??o, para a combina??o P1 e P3, foram obtidas melhores resultados de 22,17 MPa e 16,98 MPa, respectivamente, que ? maior que da outra combina??o de P2. Os resultados do mesmo padr?o foram obtidos para an?lise de flex?o onde P1 ? 1,21% e P3 de 0,96% que s?o maiores do que o resultado obtido da combina??o P2. No caso de resist?ncia ? flex?o, melhores resultados foram obtidos para a combina??o P1 de 49,07 MPa. Mas, quando foi calculado o m?dulo de Young, os valores foram diferentes do padr?o dos resultados dos outros testes realizados, com a combina??o P2 com o valor de 4,06 GPa que ? maior que das outras combina??es. Isto mostra que as fibras PALF tiveram uma influ?ncia maior com rela??o ? fibra de curau?. A an?lise dos resultados em geral demonstra que nas combina??es de duas fibras vegetais celul?sicas, uma ou a outra fibra com porcentagem maior (75%) ? a melhor op??o do que na composi??o de 50%/50%, entretanto no caso onde a aplica??o ser? para suportar cargas de flex?o, a melhor composi??o seria 50%/50%
Bahman, Ammar. "Modeling of Solar-Powered Single-Effect Absorption Cooling System and Supermarket Refrigeration/HVAC System". Scholar Commons, 2011. http://scholarcommons.usf.edu/etd/2993.
Texto completoGalv?o, Alcione Olinto. "Desenvolvimento e an?lise de material comp?sito a base de penas de frango (fibras de queratina-KF) e matriz de poli?ster insaturado". Universidade Federal do Rio Grande do Norte, 2011. http://repositorio.ufrn.br:8080/jspui/handle/123456789/15670.
Texto completoUse of natural fibres as a reinforcement material in the manufacture of composites show a series of advantages: availability, biodegradability, low weight and regeneration in relation to synthetic fibres, thus justifying its utilization. In the present research work, composites were developed with chicken feathers (KF), using unsaturated polyester resin as matrix, for diversified applications, mainly in the furniture/timber industry.At present, in Brazil the chicken feathers are used as part of the animal feed, even though this material possesses low aggregated value. The chicken feathers are hollow, light and resistant. After washing with water at room temperature, a part of the chicken feathers were treated with 2% NaOH. Composites were manufactured using treated and untreated chicken feathers with unsaturated orthothalic polyester resin and 1% peroxide as catalyser, obtained in the commerce. Samples with size 150x25x3 mm for mechanical tests were cut by laser in the composite plate. Mechanical analyses were carried out in the Laborat?rio de Metais e Ensaios Mec?nicos UFRN. All the analyses were in accordance with ASTM standards. SEM analyses were also carried out on the samples.In the analyses of the results obtained, it was observed that the composites made with untreated chicken feathers showed better results (Traction 11.406 MPa and 9.107 MPa Bending 34.947 and 20.918 MPa for samples with and without treatment respectively) compared to the composite with treated feathers. Very low values of the water absorption results, evidenced the impermeability characteristic of the feathers. From the SEM images, the structure, fracture and the fibre/matrix adsorption can be evidenced. In the flammability test, it was observed that despite the feathers having sulfur as a constituent, natural inhibitor of flame, no burning support of the composites, because the manufacturing process of the composite
O uso de fibras naturais como refor?o em comp?sitos apresenta uma s?rie de vantagens: abund?ncia, biodegradabilidade, baixo peso e regenerabilidade em rela??o ?s fibras sint?ticas, justificando sua utiliza??o. Na presente pesquisa foram desenvolvidos comp?sitos com penas de frango (KF), utilizando resina de poli?ster n?o-saturado como matriz. Atualmente, no Brasil, as penas de frango s?o utilizadas como parte de ra??o animal, por?m este produto possui um baixo valor agregado. As penas s?o um material oco, leve e resistente. Ap?s a lavagem com ?gua em temperatura ambiente uma parte das penas foi tratada com 2% de NaOH. Foram fabricados dois comp?sitos, um com as penas tratadas e outro sem tratamento, usando o processo de molde fechado por compress?o, utilizando a resina de poli?ster ortoft?lica e 1% de per?xido MEK (per?xido de metil etil cetona) como iniciador, adquiridos no com?rcio local. As amostras com 150x25x3 mm de tamanho para os ensaios mec?nicos foram cortadas a laser na placa do comp?sito. Os ensaios de tra??o e flex?o em tr?s pontos foram realizados no Laborat?rio de Metais e Ensaios Mec?nicos - UFRN. Todas as an?lises estavam de acordo com as normas da ASTM. As amostras resultantes dos ensaios mec?nicas foram avaliadas no MEV. Com base nas observa??es dos resultados nos ensaios mec?nicos, (Tra??o 11,2 Mpa e 8,3 Mpa; Flex?o 34,9 Mpa e 22,9 MPa para as amostras sem e com tratamento respectivamente) observou-se que os comp?sitos refor?ados com as penas sem tratamento apresentaram um melhor comportamento quando foram expostos a carregamentos tanto de tra??o quanto de flex?o. O ensaio de absor??o evidenciou nos valores de absor??o de ?gua, uma das caracter?sticas da prote?na existente nas penas, a queratina, a sua capaciade de impermiabiliza??o a ?gua. Nas imagens do MEV foi poss?vel verificar a estrutura da pena, as regi?es de ruptura do comp?sito e a ades?o fibra/matriz. No ensaio de inflamabilidade, observou-se que apesar das penas terem como constituinte o enxofre, inibidor natural de chama, n?o houve a susten??o da queima nos comp?sitos, devido o processo de fabrica??o do comp?sito
Silva, Jo?o Paulo Melo da. "Estudo comparativo das propriedades mec?nicas em comp?sitos da fibra modal e poliester". Universidade Federal do Rio Grande do Norte, 2012. http://repositorio.ufrn.br:8080/jspui/handle/123456789/15681.
Texto completoIn the present work, three composites with distinct reinforcements (polyester, modal e polyester + modal), all if a unsaturated orthophthalic polyester resin as matrix were used, in order to conduct a comparative study by mechanical tests and water absorption. The fibre mats were prepared in a mat preparatory by immersion developed in the Textile Engineering Laboratory. The composites were manufactured using a closed mould process by compression using an unsaturated orthophthalic polyester resin as matrix and 1% MEK (methyl ethyl ketone peroxide) as an initiator. In each composite twelve samples with the dimensions of 150x25x3 mm were cut randomly for the mechanical analysis (tension x extension, three points bending and water absorption and Scanning Electron Micsroscopy). The mechanical tests were carried out in the Laborat?rio de Metais e Ensaios Mec?nicos UFRN . All the analyses were carried out according to the ASTM norms. The resultant samples from the mechanical analysis were subjected for the Scanning Electron Microscopy analysis. Based on the results obtained, it was observed that the reinforced composite with two fibres (modal + polyester) presented better results in comparison to the other two composites both in the tension/extension as well on the three point bending tests. In the water absorption test, it was possible to observe an equilibrium in the water absorption by the modal and polyester composite, due to the union of the two fibres. In the SEM images, the regions of rupture in the composites as well as the adsorption between the fiber and the matrix could be observed
No presente trabalho foram fabricados tr?s comp?sitos com refor?os distintos (poli?ster, modal e poli?ster + modal), todos com uma matriz de resina de poli?ster ortofit?lico n?o saturado, com o objetivo de realizar um estudo comparativo atrav?s de ensaios mec?nicos e absor??o d ?gua. As mantas de fibras foram preparadas num preparador de manta por imers?o desenvolvido no Laborat?rio de Engenharia T?xtil da UFRN. Os comp?sitos foram fabricados usando o processo de molde fechado por compress?o, utilizando a resina de poli?ster ortoft?lica e 1% de per?xido MEK (per?xido de metil etil cetona) como iniciador. Em cada comp?sito foram cortadas doze amostras aleatoriamente, com as dimens?es 150x25x3 mm, para avalia??o atrav?s de ensaios mec?nicos (resist?ncia ? tra??o e ? flex?o, absor??o d agua e microscopia eletr?nica de varredura). Os ensaios de tra??o e flex?o em tr?s pontos foram realizados no Laborat?rio de Metais e Ensaios Mec?nicos - UFRN. Todas as an?lises estavam de acordo com as normas da ASTM. As amostras resultantes dos ensaios mec?nicas foram avaliadas no MEV. Com base nos resultados dos ensaios mec?nicos, observou-se que o comp?sito refor?ado com as duas fibras em conjunto (poli?ster+modal) apresentou um melhor comportamento quando foram expostos a carregamentos tanto de tra??o quanto de flex?o. No ensaio de absor??o d agua foi poss?vel observar um equilibribio na absor??o de umidade do comp?sito com modal e poli?ster, devido a uni?o das duas fibras. Nas imagens do MEV foi poss?vel ver as regi?es de ruptura do comp?sito e a ades?o entre a fibra e a matriz
Roux-Langlois, Clément. "Simulation de fissures courbes en trois dimensions avec extraction directe des facteurs d'intensité des contraintes : En vue de l'identification de lois de propagation de fatigue". Thesis, Lyon, INSA, 2014. http://www.theses.fr/2014ISAL0112/document.
Texto completoIt is necessary to understand the behavior of structures up to their failure to enhance their design. The mechanisms and phenomena undergoing failure vary according to the considered material and boundary conditions. We consider homogeneous materials for which cracks propagate in a context where behavior nonlinearities are not dominants. These conditions are matched for brittle and quasi-brittle materials and for some fatigue cracks. For the former, the main source of dissipation is the crack propagation which can be seen as the generation of a new free-surface. For the later, there is many applications where, in one loading cycle, the nonlinearities remains confined around the crack tip. The linear elastic fracture mechanics theory is then a pertinent model to approximate the structure behavior. Under such hypotheses, a singularity appears in the crack tip vicinity. The Williams' series expansion is computed from the asymptotic study of plane and anti-plane states. The stress is singular at the crack tip and the order of this singularity is one out of two. The singularity amplitude is quantified by the stress intensity factors (SIF), one for each of the three loading modes. In 3D, the crack shape is potentially complex (front curvature and non-planar crack), and no general asymptotic series expansion exists. In this PhD thesis, the 2D Williams' series in displacements are used and regularized with a finite element evolution along the front. From this 3D definition of the asymptotic fields in the crack tip vicinity, a numerical method for direct estimation of the SIF (DEK-FEM) is extended to 3D. This method is based on domain decomposition, the two domains are bounded in a weak sense on their interface. In the crack tip vicinity, the mechanical fields are approximated by a truncation of the asymptotic series expansion. Therefore, appropriate fields are used to deal with the singularity, and the associated degrees of freedom are directly the asymptotic coefficients. Among these coefficients are the SIF and the T-stresses. To bridge the scales between the structure and the crack front singularity and to increase the numerical efficiency, this method is embedded in a localized X-FEM multigrids approach. The proposed method is shown to provide an accurate evaluation of the SIF and T-stresses evolution. This approach has been developed in combination of an experimental post-processing method (full field displacement measurement through image correlation) based on the same asymptotic series expansion. The 3D images can be obtained for in situ fatigue experiments by X-ray microtomography and reconstruction. The crack geometry and the SIF are then provided by image correlation and regularization based on Williams series expansion. These data can be used for identifying a 3D fatigue crack growth law. The efficiency of the method is illustrated in 2D
Hakala, Tim. "Settling-Time Improvements in Positioning Machines Subject to Nonlinear Friction Using Adaptive Impulse Control". BYU ScholarsArchive, 2006. https://scholarsarchive.byu.edu/etd/1061.
Texto completo"Fluid Production Induced Stress Analysis Surrounding an Elliptic Fracture". Master's thesis, 2014. http://hdl.handle.net/2286/R.I.27382.
Texto completoDissertation/Thesis
Masters Thesis Mechanical Engineering 2014
MIKULOVÁ, Magda. "Psychrotrofní lipolytické bakterie a obsah volných mastných kyselin v bazénových vzorcích syrového kravského mléka". Doctoral thesis, 2012. http://www.nusl.cz/ntk/nusl-115843.
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