Title : Analysis of motivational factors for sailors in the ship class Flying Dutchmen Introduction: This diploma thesis deals with posture problems of motivational factors for sailors in the ship class Flying Dutchmen. The aim of the work was to develop a preview of the motivational factors and at the end compare the identified facts in context with similar studies in other areas. The main experimental strategy we chose a qualitative approach. Methods: The research material was developed based on semistructured interview, narrative analysis, inquiry investigation and observation. Additionally quantitative approach was used, mainly in evaluating the inquiry investigation The processing of the results, we used statistical processing in Microsoft Excel. All the results were interpreted by means of comparison in Microsoft Office Word. Results: The results showed us that the principle factors of motivation are "Positive enjoyment ", "Cooperation" and "Beloging with natur". For most of our probands was the first motive to the beginnings of the yachting community boaters. Everyone devote most of their free time sailing, this means that sailing is important in their lives, we can described as their lifestyle is not for them mere sport or form of entertainment. Keywords: Sailing, Flying Dutchmen,...

Flight and drop tests of the Martin 270 (M270) seaplane were conducted in 1955. Theoretical and empirical pressures were determined by use of Wagner’s theory and also by the Code of Federal Regulations (CFR). The pressure results from the experimental tests on the hull were compared with pressures calculated from Wagner’s theory to determine how well the theory correlated with the measured pressures. The experimental pressure data was also compared with the CFR results to determine how the current industry standard of estimating impact loads compares with actual pressures a seaplane is subjected to. Using the structural design and geometry of the M270 the seaplane hull was modeled in Maestro with a coarse mesh finite element model. The pressures from Wagner’s theory and the CFR were applied to the model of the M270 hull. The structural reactions of the drop test section were compared with the reactions determined from Maestro.

A novel continuous low-thrust fuel-efficient model predictive control strategy for multi-satellite formations flying in low earth orbit is presented. State prediction relies on a full nonlinear relative motion model, based on quasi-nonsingular relative orbital elements, including earth oblateness effects and, through state augmentation, differential drag. The optimal control problem is specically designed to incorporate latest theoretical results concerning maneuver optimality in the state-space, yielding to a sensible total delta-V reduction, while assuring feasibility and stability though imposition of a Lyapunov constraint. The controller is particularly suitable for networked architectures since it exploits the predictive strategy and the dynamics knowledge to provide robustness against feedback losses and delays. The Networked MPC is validated through real missions simulation scenarios using a high-fidelity orbital propagator which accounts for high-order geopotential, solar radiation pressure, atmospheric drag and third-body effects.

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Small satellites are growing in popularity because they offer an effective option that enables missions otherwise too schedule or cost limited. However, many possible missions require improved platform capabilities without sacrificing the cost effective nature of small satellites before they become viable. Described is the development and validation of high performance attitude determination and control for nanosatellite missions. Considered are astronomy missions, requiring very fine pointing stability, and formation flying missions requiring rapid manoeuvring while maintaining antenna coverage towards secondary pointing targets. It will be shown that power and volume limited nanosatellites are capable of this level of attitude performance by leveraging the techniques normally reserved for larger spacecraft. Discussed are attitude state estimation techniques and control laws developed for the BRITE stellar photometry constellation and CanX-4 and CanX-5 formation flying mission, along with the challenges associated with implementing and validating these designs for real space missions.

Small satellites are growing in popularity because they offer an effective option that enables missions otherwise too schedule or cost limited. However, many possible missions require improved platform capabilities without sacrificing the cost effective nature of small satellites before they become viable. Described is the development and validation of high performance attitude determination and control for nanosatellite missions. Considered are astronomy missions, requiring very fine pointing stability, and formation flying missions requiring rapid manoeuvring while maintaining antenna coverage towards secondary pointing targets. It will be shown that power and volume limited nanosatellites are capable of this level of attitude performance by leveraging the techniques normally reserved for larger spacecraft. Discussed are attitude state estimation techniques and control laws developed for the BRITE stellar photometry constellation and CanX-4 and CanX-5 formation flying mission, along with the challenges associated with implementing and validating these designs for real space missions.

This thesis contains the specific description of Group Design Project (GDP) and Individual Research Project (IRP) that are undertaken by the author and form part of the degree of Master of Science. The target of GDP is to develop a novel and unique commercial flying wing aircraft titled FW-11. FW-11 is a three-year collaborative civil aircraft project between Aviation Industry Corporation of China (AVIC) and Cranfield University. According to the market analysis result conducted by the author, 250 seats capacity and 7500 nautical miles were chosen as the design targets. The IRP is the further study of GDP, which is to enhance the competitive capability by deploying prognostics and health management (PHM) technology to the fuel system of FW-11. As a novel and brand-new technology, PHM enables the real-time transformation of system status data into alert and maintenance information during all ground or flight operating phases to improve the aircraft reliability and operating costs. Aircraft fuel system has a great impact on flight safety. Therefore, the development of fuel system PHM concept is necessary. This thesis began with an investigation of PHM, then a safety and reliability analysis of fuel system was conducted by using FHA, FMEA and FTA. According to these analyses, fuel temperature diagnosis and prognosis were chosen as a case study to improve the reliability and safety of FW-11. The PHM architecture of fuel temperature had been established. A fuel temperature prediction model was also introduced in this thesis.

The precise control of spacecraft with flexible appendages is extremely difficult. The complexity of this task is magnified many times when several flexible spacecraft must be controlled precisely and collaboratively, as in formation flying. Formation flying requires a group of spacecraft to fly in a desired trajectory while maintaining both relative positions and velocities with respect to each other. This work enhances two current state-of-the-art formation flying algorithms, specifically leader-follower and virtual-structure architectures. First, a flexible satellite model is integrated into each of these architectures. Second, input shaping is used to generate the satellites desired trajectories, thereby enhancing the performance of the system. This dissertation addresses key issues regarding the application of command generation techniques to flexible satellites controlled with formation flying control architectures. The temporal tracking and the trajectory tracking of each architecture are examined as well as the vibration characteristics of the formation satellites. Design procedures for applying trajectory shaping for the leader-follower and virtual-structure architecture are developed. Experiments performed on a flexible satellite testbed verify key simulated results.

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Environmental issues are manifest throughout our lives. Sport is no exception. The concern for sustainable sport management has precipitated efforts to reduce the ecological footprint of sport, and to use sport to raise environmental awareness. This dissertation examines the challenges of reducing the ecological footprint of an urban recreational sport: disc golf. The project consists of four studies. The ecological degradation associated with the sport of disc golf is reported in the first study. It is shown that disc golf increases soil compaction, which yields greater soil erosion and a decrease in vegetation cover. The second study examines player behaviors, and identifies two behaviors that are clearly related to the environmental degradation, and that could be reduced without interfering with the game: (1) dragging bags with disc golf equipment along the ground, and (2) using tress as practice targets. The subculture of disc golfers is explored in the third study in order to identify characteristics of the subculture that could be leveraged to foster the desired behavioral changes. Disc golfers felt a strong sense of ownership and attachment to the park in which they played, and placed a high value on the sport and the park in which they played. However, disc golfers were unaware of the environmental effects of their behaviors. In the final study, a brochure was distributed to players that informed them about the environmental damage caused by dragging bags and using trees for target practice, and that appealed to their sense of ownership and attachment to the park in which they played. A multiple baseline study of disc golfer behaviors in three parks demonstrated that the brochure reduced the target behaviors so significantly that they were virtually extinguished. It is concluded that behavioral management strategies can be useful tools for environmental management of urban sport settings. It is suggested that appeals to supportive subcultural values enable self-policing of target behaviors. It is also noted that education can be an effective intervention when the values are supportive but player ignorance of their impact has allowed environmentally damaging behaviors to be tolerated. / text