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The work in this thesis is focused on the development and validation of an automotive battery monitoring system that estimates the health of a lead-acid battery during engine cranking and provides a low state of health (SOH) warning of potential battery failure. A reliable SOH estimation should assist users in preventing a sudden battery failure and planning for battery replacement in a timely manner. Most commercial battery health estimation systems use the impedance of a battery to estimate the SOH with battery voltage and current; however, using a current sensor increases the installation cost of a system due to parts and labor. The battery SOH estimation method with the battery terminal voltage during engine cranking was previously proposed. The proposed SOH estimation system intends to improve existing methods. The proposed method requires battery voltages and temperature for a reliable SOH estimation. Without the need for a costly current sensor, the proposed SOH monitoring system is cost-effective and useful for automotive applications. Measurement results presented in this thesis show that the proposed SOH monitoring system is more effective in evaluating the health of a lead-acid battery than existing methods. A low power microcontroller equipped prototype implements the proposed SOH algorithm on a high performance ARM Cortex-M4F based MCU, TM4C123GH6PM. The power dissipation of the final prototype is approximately 144 mW during an active state and 36 mW during a sleep state. With the reliability of the proposed method and low power dissipation of the prototype, the proposed system is suitable for an on-board battery monitoring as there is no on-board warning that estimates the health of a battery in modern cars. / Master of Science

This thesis describes the development of a system to continuously monitor the battery in a car and warn the user of an upcoming battery failure. An automotive battery endures enormous strain when it starts the engine, and when it supplies loads without the engine running. Note that the current during a cranking event often exceeds 500 Amperes. Despite the strains, a car battery still typically lasts 4-6 years before requiring replacement. There is often no warning of when a battery should be replaced and there is never a good time for a battery failure. All currently available lead-acid battery monitoring systems use voltage and current sensing to monitor battery impedance and estimate battery health. However, such a system is costly due to the current sensor and typically requires an expert to operate the system. This thesis describes a prototype system to monitor battery state of health and provide advance warning of an upcoming battery failure using only voltage sensing. The prototype measures the voltage during a cranking event and determines if the battery is healthy or not. The voltage of an unhealthy battery will drop lower than a healthy one, and it will not recover as quickly. The major contributions of the proposed research to the field are an algorithm to predict automotive battery state-of-health that is temperature-dependent and a prototype implementation of the algorithm on an ARM processor development board. / Master of Science

This thesis examines the numerical solution to Burgers' equation on a finite spatial domain with various boundary conditions. We first conduct experiments to confirm the numerical solutions observed by other researchers for Neumann boundary conditions. Then we consider the case where the non-homogeneous Robin boundary conditions approach non-homogeneous Neumann conditions. Finally we numerically approximate the steady state solutions to Burgers' equation with both the homogeneous and non-homogeneous Robin boundary conditions. / Master of Science

This thesis analyzes the impact of capital budget on capital spending in the U.S. states. The analysis is based on the James Poterba's 1995 study of the impact of a capital budget on capital spending using 1962 U.S. state-level data. I first replicate Poterba's model using the 1992-1996 data set that I had constructed for this study. I then extend Poterba's model to include a set of variables that allows exploration of the specific effects of the regulatory environment on spending outcomes in each state. These are mainly categorical variables that classify states in accordance with their definition of capital expenditure, organization of capital planning process, project selection and cost estimating techniques and capital financing practices. These were constructed using the data of the 1997 NASBO survey after reviewing the suggestions of practitioners and policy makers, as well as those engaged in research in this field. The introduction of a set of budget rule/budget composition variables into the analysis is an important contribution of this study. I also introduce additional control variables such as those controlling for the age of infrastructure. This study supports the claim that government spending is determined by a host of causal factors that can be grouped into four broad categories, (1) demographic-economic factors, representing both demand for public capital and source of its financing, (2) political decision-making factors that reflect electorate/party in power preferences for spending, (3) capital stock variables that relate to the age of infrastructure and control for spending culture in a state, and (4) budget composition/spending rules. The main finding of this study is the confirmation of Poterba's finding with respect to the positive effect of capital budget on capital spending using a recent data set and longer time frame of analysis. Another major contribution of this study is a statistically significant effect of sixteen spending rule/ budget composition variables. The results of this study support the basic premise found in the literature that budget process affects capital spending. / Master of Public and International Affairs

Ultraviolet photoelectron spectroscopy measurements are presented from a variety of metals and alloys in the liquid state. For the metals, the optical density of states function is extracted from the photoemission data, by using an extended version of the three step model of Berglund and Spicer and compared to theoretical liquid density of states calculations based on a weak scattering approach which show only small deviations from the free electron parabola. The experimentally derived results for liquid lead and liquid tin reveal deviations from the simple picture with some of the solid state density of states features persisting into the liquid phase. By contrast, liquid lithium is shown to adhere more closely to the free electron model, showing a weaker deviation from the parabolic form for its experimentally derived density of states, while the same function for liquid silver is shown to be a smeared version of the solid state curve which, as explained, is not unexpected because of structural considerations. Photoemission data from liquid germanium is presented and discussed in comparison with published data for crystalline and amorphous germanium in terms of local atomic ordering. Data is presented from the liquid semiconducting lithium-lead alloy system and the similar lithium-tin alloy system which is shown incompatible with a simple ionic bonding model, and a stoichiometric structure is proposed where the unlike atom bonding is taken to be more covalent in character. Photoemission spectra are also presented from the silver- germanium alloy system which has a deep eutectic composition indicating enhanced glass forming qualities. Some change with composition can be seen in the valence band region but this cannot account for the above behaviour.

The purpose of this thesis is to examine how different news agencies around the world portray the Islamic State, using the beheading of journalist James Foley as a case study. Whether or not media outlets coverage and portrayal of the Islamic State and terrorism differs depending on region and state.  This to investigate or uncover how cultural heritage and political currents might be influencing news agencies portrayal of the Islamic State and its advances. How do different news agencies depict or picture the same events and the terror organizations advances. By using Norman Faircloug’s model for critical discourse analysis three prominent discourses are found. The conclusion is that political currents and cultural heritage does have an influence in media coverage and portrayal; news agencies belonging to different regions portray this terror organization differently but when condemning the event there is a global standardization.

It has been demonstrated that reactive magnetron sputtering can be controlled in low pumping speed vacuum system through observation of the spectral line emission by the plasma emission monitor (PEM). Confining the deposition process in an enclosed volume has provided the gettering-pumping action needed to deposit films with good quality reducing the active contamination that low pumping vacuum system suffers. TiN films of specular quality has been optimised by observing the emission line of the sputtered titanium. It was shown that optimum TiN film is formed when the consumption of nitrogen flow at the metal line set point is a maximum. This optimisation is characterised by a clear minima of ultimate resistivity and better selective optical properties. Films of TiN deposited using the balanced magnetron source had higher resistivity than the metal titanium in contrast to its bulk properties. That was explained by their lower densities. The lack of activation energy of the growing film during deposition resulted in a columnar structure separated by voids which is a normal microstructure of low film density. By adding activation energy, from an unbalanced magnetron source, a plasma beam was leaked to the substrate subjecting the growing film to energetic ions of sufficient energy to modify the structure of the film. Films were shown to have resistivities lower than the metal titanium. This characterisation was verified by examining their structure by SEM which showed dense films. The reactive gas consumption gave also a good indication of the process control and the optimisation of dielectric films of Ti02 and Zr02. Optimum films characterised by lowest absorption and high refractive index were shown to form when the consumption of oxygen is low at the lowest metalline set point within the limit of the plasma emission monitor. This shift occurred because the much tighter control of reactive gas pressure which is consequently higher for oxides than for nitrides. Films of TiN were also deposited at a low magnetTon potential. Increasing electron injection reduced the operating potential of the sputtered titanium resulting eventually in a reduction of sputtering rate and consequently a reduction in nitrogen consumption. Films made at lower target potentials had lower resistivities due to the enhanced reactivity and increasing ion current density bombarding the film.

The research presented in this thesis is on the application of the injection-locked oscillator technique to microwave balanced oscillators. The balanced oscillator design is primarily analysed using the extended resonance technique. A transmission line is connected between the two active devices, so that the active device resonate each other. The electrical length of the transmission line is also analysed for the balanced oscillation condition. The balanced oscillator can be viewed with the negative resistance model and the feedback model. The former model is characterised at a circuit plane where the feedback network is cut. By using both the negative-resistance oscillator model and the feedback model, the locking range of the oscillator is analysed by extending Kurokawa's theory. This analysis demonstrates the locking range of the injection phenomenon, where the injection frequency is either close to the free-running frequency, close to (lin) x freerunning frequency or close to n x the free-running frequency. It also reveals the effect of different injection power levels on the locking range. Injection-locked balanced oscillators for subharmonic and fundamental modes are constructed. When the balanced oscillator is in the locking state, it is clearly shown that the output signal is better stabilised and the phase noise is attenuated. The experimental results agree with the analysis. Furthermore, the spurious signal suppression in a cascaded oscillator is investigated. The other focus of this research is on the design of frequency doublers. A balanced douber is designed and integrated with a balanced injection-locked oscillator. The experimental result shows that the output signal is clean and stabilised. The other important frequency doubler design technique studied is the use of the feedforward technique to significantly eliminate the fundamental frequency component. The design and the experiment show that the fundamental component can be suppressed to better than 50 dBc.

Hexaferrites are still a very important component of the permanent magnets market because of their low price combined with reasonably attractive magnetic properties. In such a context, any improvement of the magnet data would be of great importance. In recent years, work has been carried out on improving the magnetic properties by a combined substitution of La and Co into the Sr-ferrite composition. This improvement was largely associated with an increase of coercivity and the underlying magneto-crystalline anisotropy. The possibility of replacing Sr by La and the subsequent improvement of the magnetic properties of the M-type ferrite stimulated our interest in studying other rare-earth ion substitutions. This thesis focuses on the effects of rare-earth element substitutions on the magnetic properties of strontium hexaferrite, SrM (SrFe12O19b)y chemical co-precipitation and by hydrothermal synthesis,a s well as on the properties-microstructure relationship. In order to produce the nanosized SrM powder, chemical co-precipitation was employed and subsequently proved to be an effective route for producing nanosized single domain SrM powder, where the SrM phase crystallises from the mainly amorphous co-precipitates through an exothermic reaction after calcination at >650°C. A very high intrinsic coercivity of 518. OkA/m (6509 Oe) with magnetisation at I IOOkA/m of 67 J/T. kg was obtained for the sample calcined at 850°C for 2h in air. The coercivity is close to the theoretical limit and is one of the highest values reported so far for isotropic SrM particles. Nanosized SrM powders with Sm and La-Zn additives were also studied. It was found that Sm doping increased slightly the coercivity of SrM and exhibited higher values than those of the corresponding samples with La additives. However, the values of magnetisation decreased slightly with the increase of the Sm/Sr ratio, which can be correlated with the increased proportion of weakly magnetic SrFeO3_pxh ase in the Sm doped SrM. Sm doping slightly increasedt he ferritization temperatureo f SrM. In the case of the La-Zn substitution, single phase Sri_,(,L aZn),,F e12_XO19 nanosized powders were produced successfully for all x, where x varied from 0 to 0.4. La-Zn substitution caused a decrease of the Curie temperature. The values of magnetization, remanence and coercivity decreased with La-Zn content. Unlike the results of La-Zn doped SrM particles prepared by conventional ceramic methods and the results of La-Zn doped SrM film prepared by rf sputtering, no improvement of the magnetisation was observed, which suggested that the properties of these materials are strongly processing-dependent and that the site preference of the Zn 2+ cation is not identical in all cases but would be affected by the processing route. Mainly single phase RE (RE=Sm, Nd, Pr and La) substituted SrM plate-like particles with the magnetoplumbite structure could be produced by hydrothermal synthesis and subsequent calcination. Under the particular hydrothermal conditions, RE elements did not substitute totally into the SrM structure and this resulted in incomplete reactions between Fe 3+ and Sr2+, indicated by traces of a-Fe2O3 and RE203 in all the RE substituted SrM samples. The presence of a-Fe2O3 and RE203 increased with the increase of the RE/Sr ratio. High temperature calcination homogenizes the materials and promotes the substitution of RE elements, resulting generally in the disappearance of a-Fe2O3 and RE203 after calcinations at >_ 1100°C. A higher calcination temperature was required to obtain the SrM single phase for a high RE/Sr ratio. The SrFe03_xp hase was found to be present in most of the RE substituted samples after calcination above 1100°C. Except for the La substitution, the other RE elements reduced the rate of grain growth during the calcination. Generally, the magnetization values of the RE substituted samples were almost the same as that of SrM. On the other hand, their intrinsic coercivities generally increased upon RE doping. Thus, an appropriate amount of RE substitution resulted in a useful increase in the intrinsic coercivity (18% for Sm, 14% for Pr, 11 % for Nd and 5% for La) without causing any significant deterioration in the saturation magnetisation or in the remanence. The improvement in the coercivity as a result of the RE substitutions is discussed in terms of the extrinsic effect associated with the microstructure and the intrinsic effect associated with an increase in the magnetocrystalline anisotropy. Finally, anisotropic SrM magnets with Sm substitution, which is observed to have the largest enhancement of coercivity among the other elements, were studied. All the magnets with Sm additions exhibit a bigger coercivity and remanence than those of the SrM magnet and the coercivity of the magnets increases with increasing Sm/Sr ratio. The average grain size of the samples decreases with increasing Sm/Sr ratio. EDX quantitative analysis suggests that the solubility of Sm 3+ in the SrM-type structure is very small and that the Sm3+ preferably goes into SrFe03_Xw, hich is probably located around the SrM grain boundaries. The coercivity mechanism of the magnets is nucleation controlled. The formation and the distribution of the SrFe03_x phase around the SrM grain boundraies probably provides the inhibition of SrM grain growth, the reduction of the reverse domain nucleation at the grain surface and the isolation of the SrM grains. All these factors would contribute to the improvements of the coercivity of the magnets with Sm additions.