¡@Since the Soviet Union launched its first satellite in 1957, the progress in space technology has drastically changed mankind's modus vivendi. As when nations grew more and more dependant upon the benefits brought about by the satellite technologies, space, however, became a new strategic realm where nations sought to master; consequently, contentions for national interests over this terra incognita between major global powers have evolved into a significant international security issue. Hence, as the previous military doctrines¡Xsuch as eighteenth century land power doctrine, nineteenth century sea power doctrine, and air power doctrine of the twentieth century¡Xserving as precedents, the emerging space power doctrine will undoubtedly dominate the twenty-first century global power contenders' primary national interests as well as security concerns. ¡@Over the course of the past half century, the People's Republic of China has endeavored the developments of it indigenous space technologies, and successfully positioned itself to be the third nation to have ever launched a manned space program; this manifestation also demonstrated the growing maturity and sophistication of People's Republic's space technologies. Currently, in line with America's as well as Russia's ever-expanding budget dedicated to their respective space goals, China has thus far demonstrated its political will of not falling behind the trend. Aside from the military objectives attached to the developments of China's space programs, the socio-political gains accrued to Beijing as a result of its space programs' current and future success will ensure the Communist Party's long lasting goal of glorifying the Chinese civilization as well as elevating nation's international prestige. ¡@This present treatise inquires into firstly, the surrounding circumstances and strategic environments within which China's determination for developing its indigenous space program was fermented; secondly, the crucial role play of leaderships in Beijing in formulating the successful development of the nation's space programs. Furthermore, this paper will present an in-depth analysis of the critical elements that were imperative in China's quest to achieve its space objectives, the history behind the program, as well as its present day capabilities and geo-political implications. In sum, the research findings will demonstrate the growing and ever more significant role the space technologies are playing within the conclave of the modern day Chinese strategic making apparatus.

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Stirling engines are promising candidates for applications where air breathing engines cannot be used. Self contained engines capable of operating independently of the environment are required to convert thermal energy into electric power, or to perform other necessary functions. These are ideally suited for power generation onboard spacecrafts with radioisotope heat source. These engines can power interplanetary missions to Mars and beyond. The problem of parametric analysis, sensitivity and numerical optimization of Stirling cycle engine is discussed and applied to a specific example of a 2kWe free piston Stirling engine. Stirling cycle simulation programs are generated with emphasis and adaptations peculiar to free piston design for space use. Design algorithms are generated in MatLab and optimization toolbox is used for the parametric analysis adopted in this thesis. A free piston beta Stirling engine with a linear alternator configuration has been studied for the interdependency and performance effects of various important operational parameters. The analysis has been carried out in order to optimize the primary parameters, weight vis a vis envelope (length and diameter) and stroke of the engine, to make it suitable for space use. The major cycle parameters considered are operating pressure, linear speed, dead space ratio and swept volume ratio, classified as secondary parameters. The whole analysis has been carried out at a cycle temperature ratio of 0.4 for a heat source temperature of 873 K, typical of a radioisotope heat source. The optimization is carried out for the defined design requirements viz. envelope of 50 × 50 cm , stroke of less than 10 cm, and heat source temperature of 873 K. The process of parametric optimization of the primary parameters viz engine envelope and stroke are carried out with respect to the secondary parameters. Iterations are carried out on the design programs in MatLab. The results indicate that the three primary parameters have a different set each, of the secondary parameter values when optimized to the design requirement. The fmincon solver of MatLab in the optimization tool box is selected in order to validate the optimization results. The solver is used to find a minimum of a constrained nonlinear multivariable function defining the primary parameters. The results obtained concur with the optimization results generated by the design algorithm. Further, the interdependency amongst the primary and secondary parameters is studied by generating MatLab plots for all possible combinations among the various parameters. The effect of variations in the pressure and linear speed on the system envelope and stroke are more pronounced at lower range values of the pressure and speed and the variations of the primary parameter values are constant at higher ranges. The effect of dead space ratio and swept volume ratio (>1.0) is not pronounced. The requirements in the environment of space place a number of constraints upon a Stirling engine/alternator design that are not present in terrestrial applications. High specific power is achieved by designing the engine for higher pressure and frequency operation than a terrestrial Stirling engine, and by using light weight materials where appropriate. Cylinder is the heart of the engine and it forms a major proportion of the total system mass. Mass and heat loss estimates and analysis have been carried out on the cylinder for various materials of construction. Based on the analysis feasibility exists for a Cu-Ni combination. The system would have a mass of 7kg with a specific power estimate of 0.28kW/kg and a conduction heat loss to mass ratio of 159W/kg. The system obtained by numerical analysis is modeled in system simulation software SIMULATIONX. The simulation of the system is studied and a sensitivity analysis performed in order to assess the parametric interdependency of the whole free piston Stirling engine system. The system sensitivity to piston and displacer mass is studied using the simulation model. Sensitivity results indicate that there is a range of mass values within which the system is operational, mass values outside the range makes the system non-functional. Also the range is a function of various parameters and detailed analysis is required in this direction in order to further optimize all the functional parameters. Engineering approximation is carried out using the curve fitting toolbox in MatLab to generate design equations in order to provide preliminary design data for the designer, further a scaling study is carried out at various power levels in order to assess the sensitivity of system geometry at various power levels.

The escalating technological advancements within the space sector creates new national security threats as both military and commercial actors now inhibit the space domain. By developing a separate branch within a nation's military, these kinds of new threats can be handled. However, not all countries develop a space branch. This study describes two separate cases, Sweden who has the possibility yet does not have a space force and France who has both the possibility and a military branch focused on the space domain. The findings show that Sweden's political leaders approach militarisation of space differently than France who has a historically strong political vision of space power. In order to achieve space power, this study indicates that a nation needs both vision as well as possibilities. As a result of these findings, and for future studies within the same area, a proto theoretical framework has been designed to categorize a nation based on its visions and possibilities for space power.

Space technologies and the tools of space warfare are proliferating across Earth. The use of spacepower in conflict necessitates strategic thinking. Strategic theory can guide and improve strategic thought about outer space. Drawing on strategic theory, this thesis develops a spacepower theory in the next step of a collective theory-making effort about warfare in the Space Age. This spacepower theory is based on seven distinct, complementary, and interacting propositions that aim to shift the debate of spacepower away from space weaponisation and the Revolution in Military Affairs (RMA), and towards a more holistic view of the vast possibilities granted by spacepower. This spacepower theory proposes that space warfare only has meaning in so far it works towards the command of space; that the command of space is about manipulating celestial lines of communication; that spacepower in Earth orbit is a place to conduct strategic manoeuvres to influence the wider war and grand strategic goals; and that the command of space can have direct meaning for battlefield success through its dispersing effects. The theory is based on three major strategic analogies from terrestrial strategic theory and experience. First, space warfare is a continuation of terrestrial politics. Second, space is like the sea in its most basic concepts. Third, Earth orbit is like a coastal region. The contributions of this work are a theory that assists the individual’s education on warfare in the Space Age that takes emphasis away from space-based weaponry and the RMA, and a treatise that demonstrates and encourages a pedagogical method of analysis in strategic studies. This has tentative implications for wider discussions of astropolitics in International Relations (IR) as well. IR will continue in its usefulness in the cosmos, while Terran IR today must account for the realities of the Space Age.

This dissertation evaluates the possibility of wireless power transfer (WPT) systems for space applications, with an emphasis in launch vehicles (rockets). After performing literature review for WPT systems, it was identified that magnetic resonance provides the more suited set of characteristics for this application. Advanced analysis, simulation and testing were performed to magnetic resonance WPT systems to acquire system performance insight. This was accomplished by evaluating/varying coupling configuration, load effects and magnetic element physical characteristics (i.e. wire material, loop radius, etc.). It was identified by analysis, circuit simulation and testing that the best coupling configuration for this application was series-series and series-shunt with Litz wire loop inductors. The main concern identified for the implementation of these systems for space applications was radiated emissions that could potentially generate electromagnetic interference (EMI). To address this EMI concern, we developed the Electromagnetic Compatibility Radiated Emissions Compliance Design Evaluation Approach for WPT Space Systems. This approach systematically allocates key analyses, simulations and tests procedures to predict WPT EMC compliance to NASA’s EMC standard Mil-Std-461E/F. Three prototype/magnetic elements were successfully assessed by implementing the WPT EMC design approach. The electric fields intensity generated by the WPT prototypes/magnetic elements tested were: 30.02 dBµV/m, 28.90 dBµV/m and 82.13 dBµV/m (requirement limit: 140 dBµV/m). All three prototypes successfully transferred power wirelessly and successfully met the NASA EMC requirements.