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A comparative study is carried out to investigate the most promising route towardsthe lightweight construction of a retractable mast for a sailing cargo vessel.Four design families are developed and compared. The primary criteria forjudgment are the structural mass, strength, and stiffness in relation to a providedbenchmark design. Additional evaluation criteria are the capital costsfor raw materials and manufacturing.The design space includes isotropic materials as well as fiber-reinforced polymer(FRP) solutions and is navigated by employing analytical evaluation methodssupported by finite element analysis (FEA). Restrictions to the designspace are given by a general arrangement of the benchmark design. This includesthe limitation to the ULS loads and the overall mast geometry.A review of relevant Det Norske Veritas (DNV) rules for classification is performedand the guidelines for wind turbine blades and wind-powered units(WPU) are judged most suitable to the design challenge. Relevant design principlesare implemented in the structural analysis.It is concluded that pure metal constructions imply an unreasonably large weightpenalty. Local buckling is found to disqualify FRP single-skin solutions as successfulcandidates. Secondary to that, strength concerns are the major driversfor the structural mass.The report presents two designs that are judged fit for the purpose, one is ahybrid truss structure from high strength low alloy steel (HSLA steel) and carbonfiber-reinforced polymer (CFRP). The second design is a sandwich constructionwith CFRP face sheets, a PVC foam core, and additional stiffeningmembers in steel.

The telescoping cantilever beam structure is applied in many different engineering sectors to achieve weight/space optimisation for structural integrity. There has been limited theory and analysis in the public domain of the stresses and deflections involved when applying a load to such a structure. This thesis proposes (a) The Tip Reaction Model, which adapts classical mechanics to predict deflection of a two and a three section steel telescoping cantilever beam; (b) An equation to determine the Critical buckling loads for a given configuration of the two section steel telescoping cantilever beam assembly derived from first principles, in particular the energy methods; and finally (c) the derivation of a design optimization methodology, to tackle localised buckling induced by shear, torsion and a combination of both, in the individual, constituent, hollow rectangular beam sections of the telescopic assembly. Bending stress and shear stress is numerically calculated for the same structure whilst subjected to inline and offset loading. An FEA model of the structure is solved to verify the previous deflection, stress and buckling predictions made numerically. Finally an experimental setup is conducted where deflections and stresses are measured whilst a two section assembly is subjected to various loading and boundary conditions. The results between the predicted theory, FEA and experimental setup are compared and discussed. The overall conclusion is that there is good correlation between the three sets of data.

This master's thesis makes a brief comparison of design variants of belt conveyors with variable length including examples of use. The thesis is also deals with design of travel drive of movable head, witch is a part of propel station of belt conveyor for long distance belt conveyor systems. The thesis perform static analysis of steel structure of movable head. This thesis can serve as guidance for handling similar projects. Contains basic drawings of movable head steel structure and components of the movable head travel drive.

This master’s thesis deals with a design of a telescopic axle and evaluation of the tandem suspension frame mounted on silage wagons Pöttinger Primo and Faro while they are operating a slope. Thesis describes the whole design as well as a hydraulic system and a braking system. This part also consists of maintenance and adjusting instructions. The second part of the thesis is dedicated to a slope capacity calculation based on ISO 16231-2. Strength analysis for all the parts is done, using finite element method for various working modes.

Cement penetrability is a key factor in multifilament cement composites. However, the modes of action and the concepts vary because of brittle and ductile fibers. In the case of brittle fibers such as glass, high penetrability of cement products in between the bundle filaments can lead to brittle composite behavior, and therefore addition in ductility is required. In order to have efficient bundle action and high bonding, fillers can be introduced in between the glass filaments, keeping the telescopic mode of failure but at the same time improving the bond and stress transfer within the filaments of the bundle, even at late ages, resulting in a ductile and high strength composite. On the other hand, ductile fibers such as polypropylene (PP), which also developing low bonding with the cement matrix, result in ductile cement composite but with relatively low strength. Therefore, in this case good penetrability of the cement in between the filaments of the bundle is essential in order to maximize the reinforcing efficiency of the bundle by improving bond. The penetrability of the matrix into a fabric structure and especially in between the bundle filaments made up the fabric is a result of fiber- matrix compatibility, which depends on: level of opening and spaces between the filaments, bundle surface properties including wetting and chemical affinity to the cement matrix, matrix viscosity, processing of the composite, and the nature of the fabric junctions and the resulting tightening effects of the bundle, i.e., influenced by the fabric structure itself.

O sistema de osseointegração desenvolvido por Branemark revolucionou o campo das reabilitações protéticas, incentivando os profissionais a indicar e realizar próteses do tipo overdentures. Estes dispositivos representam uma ótima alternativa para solucionar os problemas dos pacientes desdentados, insatisfeitos por diversos fatores. Várias são as associações entre os implantes e os sistemas de conexões empregados em overdentures. A literatura e a prática clínica fazem observar que na dependência do sistema de conexão empregado, há uma diferença no comportamento biomecânico, realizado por este conjunto: prótese/implante/conexão. Desta forma, é importante analisar como as tensões se distribuem sobre as estruturas que suportam estas cargas, uma vez que não existe o ligamento periodontal ao redor dos implantes que promove o mecanismo fisiológico, natural nos dentes. Assim, o objetivo desta investigação foi de avaliar, com o auxílio do método fotoelástico, o comportamento da distribuição das tensões em sobredentaduras (overdentures), suportadas por quatro implantes Ankylos®/ Dentsply®, utilizando-se o sistema protético de conexão de coroas cônicas Syncone®/ Dentsply®, onde se comparou duas formas de distribuição dos implantes, na primeira (CPM1) os implantes foram posicionados nas regiões de incisivos centrais e pré-molares e o segundo (CPM2) os implantes estavam posicionados nas regiões de caninos e pré-molares. Os modelos receberam cargas de forma crescente de 0,0 a 9,0 kg e, as tensões resultantes nas estruturas de suporte, foram analisadas fotoelasticamente. De acordo com a metodologia empregada nesta pesquisa, somos levados a concluir que: 1) Quando se associa o sistema Syncone® com overdenture ou sobredentadura, apoiada e retida sobre quatro implantes, sendo 2 localizados na região de incisivos centrais e 2 situados, diametralmente opostos, na região de segundos pré-molares na mandíbula - CPM1 - o rebordo residual é quem recebe a maior quantidade de tensões em relação aos implantes; 2) Quando se associa o sistema Syncone® com overdenture ou sobredentadura, apoiada e retida sobre 4 implantes, dispostos 2 a 2, bilateralmente e diametralmente opostos, nas regiões de caninos e pré-molares, na mandíbula (CPM2), as maiores tensões são transmitidas ao rebordo residual, sendo que os implantes suportes resultam mais preservados; 3) Comparativamente, o CPM2, aparenta ter transmitido menores tensões aos implantes que o CPM1; 4) Os implantes são preservados quanto à ocorrência de uma sobrecarga, durante a máxima intercuspidação dos arcos dentários, quando se emprega o sistema Syncone® associado à overdenture ou sobredentadura. / The osseo-integrated system develop by Branemark has revolutionized the prosthetic rehabilitation field, encourage the professionals to indicate and perform prostheses like overdentures. These devices represent an optimal alternative to solve the full dentures patient?s problems, dissatisfied for diverse factors. There are several associations between implants and prosthetic connectors employees for overdentures. The literature and the clinic practice may observe that according of the connection system employed, there is a difference into the biomechanical behavior, realized for this set: prostheses/implant/connection. From this forms, it is important to analyze how the tensions are distributing on the structures subject that support these loads, since it doesn\'t exist the periodontal ligament around the implants, what promotes the physiological mechanism of the natural teeth. Such, the purpose from this investigation was appraising, with the aid of the photoelastic method, the distribution way from the tensions at the overdentures, supported by four implants Ankylos®/ Dentsply, by using the prosthetic system of connection of conic crowns ? Syncone®/ Dentsply, were applied loads from 0,0 to 9,0kg, in crescent forms and, the tensions resulting on the support structures, have been analyzed by the photoelasthic method. Where two forms of distribution of the implantations were compared, first (CPM1) the implants were located at the regions of the central incisors and pre-molar, and as (CPM2) the implants were located at the regions of canines and pre-molar. The models had received loads of increasing form, from 0,0 to 9,0 kg and, the resultant tensions in the support structures, had been analyzed by the photoelastic method. In agreement with the methodology used in this research, we are led to conclude that: 1) When the overdenture is associated with Syncone® system, supported and retained by 4 implants, being 2 located in the region of central incisors and 2, diametrical opposing ones, in the region of the second pre-molar (CPM1) the residual alveolar ridge is who receives the biggest amount of tensions in relation to the implants; 2) When the overdenture is associated with Syncone® system, supported and retained by 4 implants, bilaterally and diametrical opposing ones, in the regions of canine and pre molar (CPM2), the biggest tensions were transmitted to the residual alveolar ridge, being the implants supports resulted more preserved; 3) Comparatively, the CPM2, seems to have transmitted less tensions to the implants than the CPM1; 4) The implants were preserved as the occurrence of an overload, during the maximum intercuspidação of the dental arcs, when the overdenture associated with Syncone® system has been used.

The emerging and competitive environment in the space technology requires the improvements in the capability of aerodynamic vehicles. This leads to the analysis in drag reduction of the vehicle along with the minimized heat transfer rate. Using forward facing solid aerospike is the simplest way among the existing drag reduction methodologies for hypersonic blunt cone bodies. But the flow oscillations associated with this aerospike makes it difficult to implement. When analyzing this flow, it can be understood that this oscillating flow can be compared to conical cavity flow. Therefore in the spiked flows, it is decided to implement the technique used in reducing the flow oscillation of the cavities. Based on this method the shallow conical cavity flow generated by the aerospike fixed ahead of a 120o blunt cone body is fissured as multiple cavities by so many disks formed from 10o cone. Now the deep conical cavities had the length to mean depth ratio of unity; this suppresses the unnecessary oscillations of the shallow cavity. The total length of the telescopic aerospike is fixed as 100mm. And one another conical tip plain aerospike of same length is designed for comparing the telescopic spike’s performance at hypersonic flow Mach numbers of 5.75 and 7.9. A three component force balance system capable of measuring drag, lift and pitching moment is designed and mounted internally into the skirt of the model. Drag measurement is done for without spike, conical tip plain spiked and telescopic spiked blunt cone body. The three configurations are tested at different angles of attack from 0 to 10 degree with a step of 2. A discrete iterative deconvolution methodology is implemented in this research work for obtaining the clean drag history from the noisy drag accelerometer signal. The drag results showed the drag reduction when compared to the without spike blunt cone body. When comparing to the plain spiked, the telescopic spiked blunt cone body has lesser drag at higher angles of attack. Heat transfer measurements are done over the blunt cone surface using the Platinum thin film gauges formed over the Macor substrate. These results and the flow visualization give better understanding of the flow and the heat flux rate caused by the flow. The enhancement in the heat flux rate over the blunt cone surface is due to the shock interaction. And in recirculation region the heat flux rate is very much lesser when compared to without spike blunt cone body. It is observed that the shock interaction in the windward side is coming closer towards the nose of the blunt cone as the angle of attack increases and the oscillation of the oblique shock also decreases. Schlieren visualization showed that there is dispersion in the oblique shock, particularly in the leeward side. In the telescopic spike there are multiple shocks generated from each and every disk which coalesces together to form a single oblique shock. And the effect of the shock generated by the telescopic spike is stronger than the effect of the shock generated by the conical tip plain spike.

O sistema de osseointegração desenvolvido por Branemark revolucionou o campo das reabilitações protéticas, incentivando os profissionais a indicar e realizar próteses do tipo overdentures. Estes dispositivos representam uma ótima alternativa para solucionar os problemas dos pacientes desdentados, insatisfeitos por diversos fatores. Várias são as associações entre os implantes e os sistemas de conexões empregados em overdentures. A literatura e a prática clínica fazem observar que na dependência do sistema de conexão empregado, há uma diferença no comportamento biomecânico, realizado por este conjunto: prótese/implante/conexão. Desta forma, é importante analisar como as tensões se distribuem sobre as estruturas que suportam estas cargas, uma vez que não existe o ligamento periodontal ao redor dos implantes que promove o mecanismo fisiológico, natural nos dentes. Assim, o objetivo desta investigação foi de avaliar, com o auxílio do método fotoelástico, o comportamento da distribuição das tensões em sobredentaduras (overdentures), suportadas por quatro implantes Ankylos®/ Dentsply®, utilizando-se o sistema protético de conexão de coroas cônicas Syncone®/ Dentsply®, onde se comparou duas formas de distribuição dos implantes, na primeira (CPM1) os implantes foram posicionados nas regiões de incisivos centrais e pré-molares e o segundo (CPM2) os implantes estavam posicionados nas regiões de caninos e pré-molares. Os modelos receberam cargas de forma crescente de 0,0 a 9,0 kg e, as tensões resultantes nas estruturas de suporte, foram analisadas fotoelasticamente. De acordo com a metodologia empregada nesta pesquisa, somos levados a concluir que: 1) Quando se associa o sistema Syncone® com overdenture ou sobredentadura, apoiada e retida sobre quatro implantes, sendo 2 localizados na região de incisivos centrais e 2 situados, diametralmente opostos, na região de segundos pré-molares na mandíbula - CPM1 - o rebordo residual é quem recebe a maior quantidade de tensões em relação aos implantes; 2) Quando se associa o sistema Syncone® com overdenture ou sobredentadura, apoiada e retida sobre 4 implantes, dispostos 2 a 2, bilateralmente e diametralmente opostos, nas regiões de caninos e pré-molares, na mandíbula (CPM2), as maiores tensões são transmitidas ao rebordo residual, sendo que os implantes suportes resultam mais preservados; 3) Comparativamente, o CPM2, aparenta ter transmitido menores tensões aos implantes que o CPM1; 4) Os implantes são preservados quanto à ocorrência de uma sobrecarga, durante a máxima intercuspidação dos arcos dentários, quando se emprega o sistema Syncone® associado à overdenture ou sobredentadura. / The osseo-integrated system develop by Branemark has revolutionized the prosthetic rehabilitation field, encourage the professionals to indicate and perform prostheses like overdentures. These devices represent an optimal alternative to solve the full dentures patient?s problems, dissatisfied for diverse factors. There are several associations between implants and prosthetic connectors employees for overdentures. The literature and the clinic practice may observe that according of the connection system employed, there is a difference into the biomechanical behavior, realized for this set: prostheses/implant/connection. From this forms, it is important to analyze how the tensions are distributing on the structures subject that support these loads, since it doesn\'t exist the periodontal ligament around the implants, what promotes the physiological mechanism of the natural teeth. Such, the purpose from this investigation was appraising, with the aid of the photoelastic method, the distribution way from the tensions at the overdentures, supported by four implants Ankylos®/ Dentsply, by using the prosthetic system of connection of conic crowns ? Syncone®/ Dentsply, were applied loads from 0,0 to 9,0kg, in crescent forms and, the tensions resulting on the support structures, have been analyzed by the photoelasthic method. Where two forms of distribution of the implantations were compared, first (CPM1) the implants were located at the regions of the central incisors and pre-molar, and as (CPM2) the implants were located at the regions of canines and pre-molar. The models had received loads of increasing form, from 0,0 to 9,0 kg and, the resultant tensions in the support structures, had been analyzed by the photoelastic method. In agreement with the methodology used in this research, we are led to conclude that: 1) When the overdenture is associated with Syncone® system, supported and retained by 4 implants, being 2 located in the region of central incisors and 2, diametrical opposing ones, in the region of the second pre-molar (CPM1) the residual alveolar ridge is who receives the biggest amount of tensions in relation to the implants; 2) When the overdenture is associated with Syncone® system, supported and retained by 4 implants, bilaterally and diametrical opposing ones, in the regions of canine and pre molar (CPM2), the biggest tensions were transmitted to the residual alveolar ridge, being the implants supports resulted more preserved; 3) Comparatively, the CPM2, seems to have transmitted less tensions to the implants than the CPM1; 4) The implants were preserved as the occurrence of an overload, during the maximum intercuspidação of the dental arcs, when the overdenture associated with Syncone® system has been used.

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