AbstractThis thesis discuss how United Parcel Service (UPS) develop its aircraft maintenanceprogram after import of McDonnell Douglas MD-11aircraft and the process of exporting newMD-11 aircraft from manufacturer in USA to European operator as passenger aircraft. It alsodiscusses the process of importing the same types of aircraft as freight carrier. The aircraftundergo, through different modifications at Singapore Technologies Aerospace (STA)conversion from passenger to freight carrier, a program specially designed for UPS airlinesbefore import to USA.The thesis work was carried out in close communication with the maintenance department atUPS in California and Kentucky, McDonnell Douglas manufacturing plant in Missouri and atBoeing in Washington.The aim of this thesis was to examine and discuss the rules and regulation of import andexports of aircraft in U.S. based on UPS import of MD-11 aircraft. Furthermore, to discussthe transformation of maintenance program from one airline to another, with emphasis onhow U.S. operator develop their maintenance program.McDonnell Douglas manufactures MD-11 aircraft, and as aircraft manufacturing companythey must comply with the United States of America Federal aviation regulation part 21requirements. Besides that, the company has bilateral agreement with the buying countrySwitzerland, facilitating the reciprocal airworthiness certification of civil aeronauticalproducts exported between the two parties. Bilateral airworthiness agreement or aviationsafety agreement with implementation procedure for airworthiness facilitate the airworthinesstechnical cooperation between the Federal Aviation Administration (FAA) and its counterpartSwitzerland Civil Aviation Authorities (SCAA).UPS buy MD-11 aircraft after being modified as freight carriers. In order to obtainairworthiness certification from FAA UPS and Boeing secures that the aircraft is airworthyand have got appropriate overall maintenance service through a careful investigation processof the technical history and background of the aircraft. After receiving the FAA certificateUPS in cooperation with Boeing develop the maintenance program, before the aircraft isassigned for service in the UPS fleet.During my work it has been difficult to find information about the technical history of theaircraft, mainly because the first operator Swissair became bankrupt and all documentationwas transferred to Boeing and then to UPS. There were also many companies involved in theprocess of converting passenger aircraft to freight carrier, like ST Aero Subsidiary, Sasco inSingapore and Boeing.The work can be used as a reference to check what part of FAA deals and documents areneeded for import and export of aircraft, and what should be done to start the import andexport process. It guides the reader to an immediate understanding of regulatory organizationand their particular departments or part numbers.

Thesis (Ph.D.) -- University of Texas at Arlington, 2008.

No description available.

Thesis (M.S.)--Rutgers University, 2008. / "Graduate Program in Mechanical and Aerospace Engineering." Includes bibliographical references (p. 80-81).

No description available.

The objective of this dissertation is to provide, for a fiber reinforced MMC, an understanding of the evolution of strains as a result of thermo-mechanical loadings and the relationship of the deformation evolution to microstructural factors. Both analytical and finite element approaches were used to predict global and local properties. The analytical approach involved rigorous modifications to the shear-lag model to account for fiber end effects. It was demonstrated that the modification not only results in a correct prediction of the modulus increases in the small aspect ratio regime, but is also able to correctly predict the values of local stress variations in the matrix and whisker. The elasto-plastic behavior of the composite including fiber/fiber interactions was investigated in detail. Cyclic stress-strain hysteresis and Bauschinger effect due to the presence of fibers was also analyzed. It was found that plastic constraint generates a triaxiality in the matrix and so gives a substantial increase of fiber axial stress and an elevation of composite flow stress. Detailed deformation evolution was evaluated both under monotonic and fatigue conditions. Role of thermal residual stresses due to thermal mismatch in MMCs were investigated using the thermo-elasto-plastic FEA with temperature dependent matrix properties. It was found that the spatial distribution of the residual stresses during cooling is sensitive to constraint effects. The evolution of the "caging" plasticity surrounding fibers during cooling including the shape and size of the plastic zones were determined. While FEA solutions give good results, the application of FEA to composites requires careful attention to the geometry of the optimum mesh used in the analysis. The optimization strategy was based on an error energy norm calculation for global convergence and traction differential approach for local convergence at the fiber/matrix interface. It was shown that this optimization approach provides the optimum mesh with a much more rapid convergence than conventional automatic codes. The mesh patterns generated are also shown to be significantly different from using this approach. A converged local property values can be obtained using a significantly lower degree of freedom than by conventional methods.

This dissertation presents the analytical and numerical investigation of the response of a slab-supported liquid storage tank taking into account soil-structure interaction and nonlinear uplift effect. The dissertation consists of two parts. In the first part, a generalized approach based on the variational principle is developed to analyze the dynamic response of liquid storage tanks taking into account soil-structure interaction. Two types of tank movements are studied: (i) a liquid storage tank on a deformable soil undergoing lateral and rocking motion; (ii) a liquid storage tank on a deformable soil subjected to a vertical excitation. Also in this part of the analysis, governing equations for the liquid sloshing motion in a flexible tank are derived in a concise form. Examples with various properties are presented for the two types of tank movements to illustrate the significant effects of soil-structure interaction. Comprehensive numerical data are also presented which may be used readily in design applications. The second part studies the nonlinear uplift behavior of a liquid storage tank from its rigid supporting slab under static loadings. In this part of the study, the nonlinear large deflexion plate theory is used to model the tank bottom plate while, for simplicity, the linear shell theory is used for describing the tank shell. To describe the uplift behavior of the bottom plate, a set of nonlinear differential equations and the corresponding boundary conditions for the plate are derived using the variational principle. According to the interface conditions between the tank shell and the bottom plate, a complete nonlinear boundary value problem is defined for the uplifting tank system. An approximate solution procedure based on the Ritz method is developed for such an uplifting tank system. An example is also provided to show the tank performance during its uplifting.

This thesis consists of two closely related parts: Microstructure characterization and homogenization. Homogenization is a procedure to determine the effective properties of a material on macroscopic scale based on its heterogeneity on microscopic scale. The effective properties of a material are dependent on the spacial distribution of heterogeneity such as the distributions of material phases, the shapes of the continents, the distribution of microcracks, etc. The determination of the distribution of this geometrical heterogeneity is the task of microstructure characterization. The originality of the following work is claimed by the author: (1) Microstructure characterization: (a) Revealed a simple and useful relationship between volume fraction and mean chord-length. Volume fraction is the most important statistical property in homogenization and many other fields. Mean chord-length of a phase is mean size of the continents of that phase, which is easy to measure from the profile of material cross-sections. (b) Developed a method to obtain the two-point probability function for general anisotropic random material based on chord-length distribution and chord-center distribution. The two-point probability is the probability of finding the g-th phase at point P and finding the h-th phase at point Q simultaneously. Two-point probability has been identified as the basic function for characterizing the microstructures of random materials for the purpose of homogenization. (c) Introduced the concept of subphase which enables us to characterize the microstructure as detailed as one wishes without lazy higher order probabilities but more and more subphases. Materials are conventionally considered as multi-phase in terms of the difference of the mechanical properties of the continents such as elastic moduli and permeabilities. These multi-phase materials can be subdivided into more phases in terms of the geometrical differences (size, orientation of continents neighbor continents). Generally, to characterize the microstructure with n-point probabilities, higher-point probabilities are necessary in order to determine the microstructures in detailed. However, this will cause difficulties in two aspects. Firstly, for n $>$ 3, the n-point probabilities are usually very complex and difficult to obtain. Secondly, the complexity of the n-point probabilities will further cause difficulties in homogenization. These difficulties are overcome at a large degree by making subphases and combining the linear model of two-point probability. (2) Homogenization: (a) Developed a homogenization method for general anisotropic random materials with a probability approach. With this method, the effective moduli of n-phase anisotropic random elastic materials can be found. (b) Developed a homogenization method for conductivity problems for general anisotropic random materials with approach. The method can be used to calculate the effective permeabilities of n-phase anisotropic random materials. (c) Developed a homogenization method for randomly microcracking materials. With this method, the effective moduli of randomly cracking materials can found. The cracks under consideration can be any shape, any orientation distribution and dry or fluid-filled. It should be emphasized that the interaction between phases or cracks is fully considered in all these three methods. The effects of microstructures on effective properties are brought to the lights. In particular, the following effects are demonstrated: effects of microstructures on effective Young's moduli, effects of microcrack distributions on effective Young moduli, and effects of microstructures on effective permeabilities.

<p>Detta examensarbete på C-nivå behandlar design av en snöskoter. Uppdragsgivaren är företaget SnoWolverine som vill utveckla en snöskoter med tre drivband varav två placerade i fronten.</p><p>Den omfattande informationsinsamling som har skett under arbetets gång har visat att en trebandad skoter, som har utmärkt framkomlighet, har en stor marknad. De lösningar som finns på marknaden, främst fyrhjuling med bandsats, har alla kompromisser.</p><p>Produktutvecklingsverktyg som funktionsanalys och QFD har använts i processen. Stort fokus har legat på utveckling av formspråket för snöskoter och utvecklingen av smarta funktioner som efterfrågas av målgruppen.</p><p>Resultatet är en kraftfull snöskoter med ett kompakt utseende. Främre boggin är gjord så utrymmessparande som möjligt och designad för att vara robust. Unika funktioner är bland annat en vindtunnel som fungerar som vindruta, frontbåge med vinschfäste, utfällbar sadel och förvaringslösningar.</p>

<p>Examensarbetet är utfört i samarbete med företaget Mil Tech i Västerås. Arbetet har gått ut på att konvertera en redan existerande turbojetmotor med dragkraft på 110 Newton till en turboaxelmotor där effekten tas ut via en axel. Konverteringen av turbojetmotorn till en turboaxelmotor sker genom att konstruera en modul bestående av ett friturbinsteg som fästes på turbojetmotorn. Arbetets fokus har legat på att få en lättillverkad och enkel moduluppbyggt friturbinsteg som med få medel kan fästas direkt på turbojetmotorns utloppsdel utan att behöva modifiera turbojetmotorn. Det moduluppbyggda friturbinsteget innehåller alla de mekaniska detaljer som gör en konvertering från turbojetdrift till turboaxeldrift möjlig. Arbetet har inletts med att ta fram termodynamiska beräkningar för att avgöra motorns prestanda och motorns fysikaliska krav på design, konstruktion, material och hållfasthet. Examensarbetet innehåller solidmodeller samt konstruktionsritningar som gör det möjligt att utifrån detta bygga en fungerande friturbinmodul.</p>