The ability of waterborne coatings to adhere to polypropylene-based substrates is a challenge in the automotive industry. This thesis seeks to explore novel methods to improve the adhesion and provide coated substrates of an industrial standard. Two methods are explored, whereby a physical entanglement method is found to be unsuccessful but a chemical bonding method is found to give patentable results. It is found that the UV curing of carbene precursors as candidate adhesion promoters, gives an adhesive force which is comparable to the industrial state of the art method, flaming. Initially, the UV energy initiates CH insertion reactions, which covalently graft the adhesion promoter to the polypropylene surface. Secondly, the hydrophilic functional groups of the adhesion promoter adhere to the waterborne basecoat, thus optimal adhesion is achieved. Statistical modelling of the results reveals that the adhesive strength depends on the UV intensity, the adhesion promoter concentration and functional group type. To explore the industrial applicability, the safety and stability during storage and the aesthetics of the adhesion promoters were investigated. This research is the first step to developing a formulation that is able to replace the current flaming method.

Ti-5Al-5Mo-5V-3Cr (Ti-5553), a relatively new generation beta titanium alloy has the advantage of high strength. It is a current generation alloy used in landing gear. Currently, landing gear components are large scale and processed through forging, followed by complex heat treatments. HIPping (hot isostatic pressing) is an alternative way to process this alloy. In this project, work was carried out on investigating microstructures and mechanical properties of HIPped Ti-5553 alloy. During comparisons on fracture toughness of different types of specimens, specimens are first heat treated to a similar strength level. And fracture toughness values are calculated at the same strength level circumstance. Various microstructures are obtained through different heat treatments. Different microstructures can be achieved through specified treated temperature/ time and quenching methods. Results show that larger grain size and coarser intergranular lath-like grain boundary alpha can improve the fracture toughness. One shell-like microstructure is obtained through different heat treatment conditions. Mechanical test was carried out on this kind of microstructure and compared to normal beta annealed microstructures. To investigate the influence of microstructure on fracture toughness, techniques including optical microscope (OM), scanning electron microscope (SEM), and confocal laser scanning microscope have been used.

In this study, loss and loading characteristics of compressor tandem blades are evaluated. Whole study was focused on change of the total camber so called turning angle. Effects of camber change were investigated in terms of loss and loading characteristics. Methodology was increasing overall camber first by aligning angular positions of blades and second, if required, using more cambered airfoils. 2-dimensional cascade flow CFD analyses were performed to obtain loss-loading information of different tandem blade combinations. Acquired results were compared with the classical axial compressor blades&rsquo / loading and loss characteristics which were obtained from literature. Results showed that most of the time tandem blade configuration performed better than the single blade counterpart in 2-dimensional cascade flow. Lastly, to clarify the benefit of the study and present the gained performance in numbers, only one cascade flow CFD analysis was performed for a classical single compressor blade. Loss and loading results were compared with the tandem blade counterpart where single and tandem configurations both having the same degree of camber. It was clearly seen that tandem blade performed better again.

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The anti-torque mechanism of a NOTAR helicopter is a complex system including vertical tail and pressurized tail boom which provides air ejection used for both circulation control around the boom and creating directed jet air at the end of the boom. This thesis targets the modeling of this mechanism and integrating it to a helicopter simulation model. Flight tests are performed on the MD 600N helicopter to verify the results. Finally, the simulation is compared with flight test data.

Varying missile configurations may create uncertainty for a missile control algorithm developed with linear control theory, for instance the control system performance requirements may not be satisfied anymore. Missile configuration may change during the missile design period due to variations in subsystem locations, subsystem weights and missile geometry. Likewise, burning propellant, deployment of aerodynamic surfaces and wings with varying sweep angle can be considered as in-flight missile configuration changes. This thesis study addresses development and analysis of an adaptive missile control algorithm to account for the uncertain effects caused by varying missile configuration. Control algorithms, designed using pole placement, are augmented with adaptive neural networks. The resulting controller is a type of model reference adaptive controller. Adaptation characteristics of the augmented control algorithms are investigated to changing center of pressure location and missile geometry. Analyses are performed for three different missile configurations using simulation.

To accommodate the expected growth of the air transport industry, the Air Traffic Management (ATM) system is required to increase its performance in terms of capacity, efficiency and security whilst maintaining adequate levels of safety and reducing the environmental impact of aircraft operations. In addition, there is a urgent need to allow the different actors in the ATM system the flexibility to accommodate their preferences,so that they can better pursue their respective business objectives. To deal effectively with all these challenges, the current trend is to increase the levels of automation and integration in the system. Different ATM modernisation initiatives pursuit the shift towards a Trajectory Base Operations (TBO) environment, where different ATM users (e.g., Air Navigation Service Providers (ANSP), Airlines Operations Center (AOC), pi- lots, controllers, airport authorities) will exchange trajectory-related information in order to collaboratively make decisions in an e±ficient and fair way. An increasing number of Decision Support Tools (DSTs) are being developed and implemented to enhance both airborne and ground-based automation systems to support the human in TBO. Since these DSTs have to help humans to make decisions in TBO, they must contain the capability to predict trajectories. However, different DSTs will in principle rely on different trajectory predictors (TP), which may produce different, inconsistent trajectories for the same flight. This lack of consistency among predictions is seen as a key issue for the integration of current and future DSTs. Coordination between TPs is the key to ensure coordination between air-ground, ground -ground and air-air DSTs and hence the successful evolution and application of the TBO concept. This thesis proposes a standard method to describe trajectories that can allow different DSTs to express and exchange their views of the predicted trajectory of an aircraft. This method, called the Aircraft Intent Description Language (AIDL), provides the necessary mechanisms to formulate the aircraft intent. The aircraft intent is defined as the unambiguous description of how the aircraft is to be operated within a certain time frame. Since the mathematical formulation of this concept is needed for the computation of a trajectory, each TP has their own format of aircraft intent. However, the uncoordinated research in trajectory prediction has driven to different models of this aircraft intent,which has precluded its use to coordinate trajectory predictions of different TPs. The use of the AIDL as an standard mean to describe trajectories permits an easy construction and manipulation of trajectories between different TPs. The scope of this thesis is limited to an AIDL that describes airborne operations of civil aircraft, in particular turbofan and turbojet aircraft. However, the methodology exposed in this thesis to obtain the AIDL can be easily applied to ground operations and other type of aircraft and air vehicles (e.g., propellers, helicopters) to extend the scope and applicability of the AIDL. The AIDL is characterised by an alphabet and a grammar. The AIDL grammar contains both lexical and syntactical rules. These rules ensure that the aircraft intent contains the necessary and sufficient information that is needed to compute a trajectory. The development of these rules is based on a rigourous mathematical analysis using Differential Algebraic Equations (DAE) theory. The lexical rules in the AIDL's grammar govern the formulation of the words of the language by combining elements from the AIDL's alphabet. This alphabet contains a set of atomic primitives, equivalent to the letters in the English alphabet, called instructions, which capture basic commands and guidance modes at the disposal of the pilot/FMS to direct the operation of the aircraft in the ATM context. Instructions can be seen as minimal indivisible pieces of information describing distinct ways of closing one of the aircraft motion's degrees of freedom. Mathematically, an instruction is characterised by an equation that is to be satisfied simultaneously with the equations of motion during a certain time interval, denoted as the execution interval of the instructions. The words of the AIDL are called operations. An operation represents an elemental aircraft behaviour that determines its motion unambiguously during a specific time interval denoted as the operation interval. An operation is the result of a set of compatible instructions simultaneously active during the corresponding operation interval. The syntactical rules in the AIDL govern the definition of sentences, which are formed by sequences of operations. These rules allow expressing any possible behaviour that can be elicited from an aircraft in the ATM context. While each DST may have a different input format to describe aircraft intent, the AIDL is designed in such a way that these different inputs can be seen as 'dialects' of the AIDL. Thus, the AIDL can be used as a lingua franca by different the DSTs, which would use it as the common standard to communicate aircraft intent with each other. The possible applications of the AIDL in a TBO environment are manifold. For instance, aircraft intent information expressed using the AIDL could be exchanged as part of a negotiation process between airborne and ground-based automation systems. Air-air synchronisation based on aircraft intent could permit the coordinated operation of Unmanned aerial vehicles (UAVs) by means of exchanging their future behaviour expressed as aircraft intent. Ground-ground aircraft intent sharing would enable a common and efficient treatment of aircraft trajectories in such a way that any amendment could be easily shared between different automation tools.

The outsourcing of IT services is a significant and well-established business activity in service management for many companies worldwide. IT outsourcing has gradually increased in recent times but, although much has been written about this phenomenon, there is little in existing literature that studies the IT outsourcing process in its entirety in the German automotive industry. The objective of this research is to develop a new process model for IT outsourcing in the German automotive industry. The research is exploratory in nature and is based on a qualitative case study methodology. An overarching process model based on nine sub-processes is constructed, reflecting the main stages in IT outsourcing operations, and a number of aspects of each sub-process are researched. Through interview analysis that complements a detailed literature review, the main stakeholders and success factors are established, and key steps and activities are identified. A range of different practical applications in each sub-process are also developed. The outcome of this research provides the basis for a range of analytical materials to complement the existing literature, and these also provide the basis for further research and development. The results and associated applications will also of value to practitioners working in this field.

Wingtip vortices are extremely important phenomena in fluid dynamics for their negative effects in many applications. Despite the many studies on this particular flow, the current understanding is still poor in providing a form base for the design of effective tip geometry modifications and vortex control devices. A rectangular wing with squared and rounded wingtips was tested in order to identify the main mechanisms involved in the formation of the vortex on the wing and in its early development in the wake. The complementarity of a number of experimental techniques adopted, such as surface flow visualizations, wall pressure measurements, smoke visualizations and stereoscopic particle image velocimetry (SPIV), gave a richer insight of the physics and the basic mechanisms of the vortex development. Furthermore, a large number of configurations were tested exploring the effects of several parameters such as wing chord, aspect ratio, wingtip geometry, angle of attack and Reynolds number. The development of the vortex along the wing showed the formation of several secondary vortices which interacted with the primary vortex generating low frequency fluctuations. The structure of the flow at this stage was analysed introducing a compact description through characteristic lines of the vortex system defined from the velocity vector field in the vicinity of the wing surface. The high spatial resolution achieved by the SPIV arrangement allowed a deeper understanding of the vortex structure in the early wake and the turbulence production and dissipation within the vortex core. The relaminarization process of the vortex core promoted by centrifugal motion was observed. The relation between vortex meandering, turbulence, secondary vortices and wake sheet was discussed. A comparison of different methods for the averaging of instantaneous planar vector fields was performed showing the effects and importance of the meandering. An axial acceleration of the flow within the vortex was observed and the formation of different axial flow distributions was discussed. A minimum wake-like flow of 0.62 and a maximum jet-like flow of 1.7 times the freestream velocity were measured and a linear relation between a vortex circulation parameter and the axial velocity peak was found.

The main purpose of this research is the analysis, development and implementation of a precise autonomous orbit control system for a spacecraft in low Earth orbit. This thesis work represents a step forward in the theoretical formalization and implementation of an on-board orbit maintenance system. Two main approaches are identified for the realization of an on-board orbit control system. The first is the reconsideration and further development of state-of-the-art orbit control methods from the perspective of autonomy. A step forward is then taken in the direction of the definition of a general and rigorous formalization of the autonomous orbit control problem. The problem of the autonomous absolute orbit control is considered as a specific case of two spacecraft in formation in which one, the reference, is virtual and affected only by the Earth's gravitational field. A new parametrization, the relative Earth-Fixed elements, analogous to the relative orbital elements used for formation control, is introduced to describe the relative motion of the real and reference sub-satellite points on the Earth surface. An extensive discussion is dedicated to the reference orbit selection and generation process and the analysis of the free motion of a spacecraft in low Earth orbit. The reference orbit defines the spacecraft's nominal trajectory designed to satisfy the mission requirements. The actual orbit is kept within certain bounds defined with respect to the reference orbit. The generation process of the reference orbit is dealt in detail as it is the fundamental starting point of the orbit control chain. The free motion analysis is essential to understand the orbit perturbation environment which causes the deviation of the actual from the nominal trajectory. The use of the precise orbit determination data of the missions PRISMA and TerraSAR-X guarantee the reliability of the results of this analysis and the understanding of the orbit's perturbation environments at an altitude of 700 and 500 km. This study helps the definition of a proper control strategy. The control algorithms developed in the thesis can be divided into the two broad categories of analytical and numerical. An analytical algorithm for the maintenance of a repeat-track orbit is developed from the state-of-the-art methods and new analytical formulations for the reference orbit acquisition under different constraints and requirements are presented. The virtual formation method for the absolute orbit control is formalized by means of the relative Earth-fixed elements described previously. The state-space representation is used for the mathematical formulation of the problem. A linear and a quadratic optimal regulators, based on this model, are designed for the in-plane and out-of-plane absolute orbit control. Numerical simulations are performed for the validation of the control methods. The test platform includes a very accurate orbit propagator, the flight software and allows the simulation of actuators and navigation errors. The simulation results are evaluated from a performance and operational point of view in order to formulate a first conclusion about the advantages and disadvantages of the different control techniques. The main differences between the considered analytical and numerical control methods are outlined. The practical implementation of a precise autonomous orbit control system for a spacecraft in low Earth orbit is then described in detail. The on-board guidance, navigation and control software development, implementation and testing of the PRISMA mission, to which the author of this thesis contributed, is described. The attention is focused on the technological aspects implied by the realization of the autonomous orbit control system tested in-flight with the autonomous orbit keeping experiment on PRISMA. Among the several innovative aspects of the flight software development, some space is dedicated to the advanced software validation and testing realized on the formation flying test-bed at DLR, the German Aerospace Center, which played a fundamental role in the realization of the PRISMA mission and its experiments. Finally, the flight results of the autonomous orbit keeping experiment on the PRISMA mission, a fundamental milestone of this research work, are presented. This in-flight experiment took place in the summer of 2011 and demonstrated the capability of autonomous precise absolute orbit control using the analytical control method developed in this thesis.