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An evaluation of the specific activity concentrations associated with technologically enhanced naturally occurring radioactive materials (TENORM) and anthropogenic radionuclides has been undertaken, with particular focus on produced water from the Kuwait oil industry. This work is part of a systematic study to provide a radiological map of the outer boundary of the produced water lagoon located in the Minagish oil field in the south west region of the State of Kuwait. This particular lagoon contains material from the discharge of produced water which is a by-product of oil production in the region. The lagoon samples were prepared and placed into sealed, marinelli beakers for a full gamma-ray spectrometric analysis using a high-resolution, low-background, high-purity germanium detection systems at the University of Surrey Environmental Radioactivity Laboratory. Of particular interest are the calculation of the activity concentrations associated with members of the decay chains following decays of the primordial radionuclides of the 238U chain (226Ra, 214Pb, 214Bi) and the 232Th chain (228Ra, 228Ac, 212Pb, 212Bi, 208Tl), and the enhanced concentrations of radium isotopes. This thesis presents overview of the experimental samples which have been measured and the analysis techniques applied, including isotopic correlation plots across the sample region. The result shows the expected significant increase in 226Ra (and progeny) concentrations compared to the NORM values were taken from outside of the lagoon, with 226Ra activity concentrations ranging from approximately 10 Bq/kg to 2 kBq/kg from different samples. Radium equivalent and hazard indices are calculated for different regions of the pool boundary, with some regions have hardard indices greater than unity, and therefore constituting a potential radiological hazard. The analysis also investigates the correlations between members of the 232Th and 238U chain in these samples, and shows evidence for enhancement of radium isotopes (226Ra and 228Ra) in the lagoon produced water samples compared to the background levels.

We study the masses of the low-lying charm and bottom mesons within the framework of heavy-hadron chiral perturbation theory. We work to third order in the chiral expansion, where meson loops contribute. In contrast to previous approaches, we use physical meson masses in evaluating these loops. This ensures that their imaginary parts are consistent with the observed widths of the D-mesons. The lowest odd- and even-parity, strange and non-strange mesons provide enough constraints to determine only certain linear combinations of the low-energy constants (LECs) in the effective Lagrangian. We comment on how lattice QCD could provide further information to disentangle these constants. Then we use the results from the charm sector to predict the spectrum of odd- and even-parity of the bottom mesons. The predicted masses from our theory are in good agreement with experimentally measured masses for the case of the odd-parity sector. For the even-parity sector, the $B$-meson states have not yet been observed; thus, our results provide useful information for experimentalists investigating such states. The near degeneracy of nonstrange and strange scalar $B$ mesons is confirmed in our predictions using $\mathrm{HHChPT}$. Finally,we show why previous approaches of using $\mathrm{HHChPT}$ in studying the mass degeneracy in the scalar states of charm and bottom meson sectors gave unsatisfactory results. Interactions between these heavy mesons are treated using effective theories similar to those used to study nuclear forces. We first look at a strongly-interacting channel which produces a bound or virtual state and a dimer state which couples weakly to a weakly-interacting channel to produce a narrow resonance. We also look at the short-range interactions in two channels. We consider two cases: two channels where one has a strong $s$-wave interaction which produces bound or virtual states, and a dimer state which couples weakly to weakly-coupled channels which in turn can produce narrow resonances. For each of these systems, we use well-defined power-counting schemes. The results can be used to investigate resonances in the charmonium and bottomonium systems. We demonstrate how the method can be applied to the $X(3872)$. The widths of the $X(3872)$ for decay processes to $\bar{D}^0 D^{*0}$ and $\bar{D}^0D^0\pi$ are calculated. We use these results to obtain the line shapes of the $X(3872)$ under different assumptions about the nature of this state.

Planning mobilities in contemporary cities, particularly in developing countries, increasingly focuses on promoting motorised transport (MT) at the expense – side-lined if not banned – of non-motorised transport (NMT). As NMT serves the needs of a range of users, decisions of this kind are highly politicised favouring some forms of mobility, and interest, over others; this raises concerns about justice in access to transport. To planners and decision-makers the question of just mobilities - a concept developed in this research combining literature mainly on social justice and mobilities - poses a range of challenges: equitable distribution of direct/indirect benefits and burdens, fair process of decision making and execution in introduction or restriction/ban of any given transport mode or infrastructure, justification of motivations in political terms. Apart from redressing weakness in sustainability studies on mobility and transport, the proposition provides a broader framework to look into the distribution of existing and potential human mobilities, process and associated motivations (politics). The framework is used to explore the impact of a planning intervention – rickshaw bans/restrictions in Dhaka, Bangladesh - on the users at household level. Around one million rickshaws – a human pedalled tri-cycle usually carrying two persons – shared more than one-third of the total of 19.58 million trips in Dhaka in 2009. The volume of passengers transported (7.6 million person-trips/day in 2009), is equally astonishing; close to double the highest number of passengers (4.4 million) carried by London Tube in a single day during the 2012 Olympics. Yet in the name of increasing mobility rickshaws are being restricted/banned in Dhaka roads, particularly since 2002. The study hypothesis is that the withdrawal of rickshaws from the roads is a manifestation of unjust mobilities in the (transport) planning; devised by biased studies and plans, and fuelled by vested motivations. While short and medium distance travellers, women, school going children and their guardians, aged and sick members of the household and non-work activities are adversely affected by the decision; long distance activities, work trips and car-users are benefitted. This research also reveals a cross-sectoral, informal and productive global to local coalition against NMT in an uneven geography of power relations and multiple interests; which is also contextual and relevant to cities in developing countries in Asia and elsewhere in the globe. Apart from reviewing a broad range of theoretical and empirical literature, the research collected information on individual and household mobility patterns, on the effects of the ban/restriction and on potential modal options and preferences using a combination of questionnaire surveys, semi-structured interviews and focus group discussions.

This thesis describes an investigation into use of interactive computer simulations software in primary science education. The research questions are what effects teaching with interactive computer simulations have on students’ achievement, their conceptual change in particular science topics and on their attitudes. The question was investigated in an intervention study that tested use of simulations in two different pedagogical environments. The first environment used simulations in a computer laboratory, with students using blended learning (combining computer-based learning with non-computer learning). In this environment students worked independently on the computer. The second environment is class teaching. In this environment, the simulation was used on one computer, controlled by the teacher, in front of the class. The study also investigated ease of use and looked into practical consideration of computer-based teaching expressed by students and teachers. Three science topics were studied. The novelty of the research is using computer simulations in an Arabic nation, which has widespread use of traditional didactic-oriented pedagogy. Recent educational reforms have made demand for more student-oriented teaching, with use of practical experiments in primary science. This major change is difficult to implement for practical reasons, and the study therefore asks if computer simulations may work as an alternative approach to reach the same aims. The theoretical frameworks for the study are constructivism, conceptual change and cognitive multi-media theory. The first of these looks at the role of the student in learning, the second takes into consideration that students enter school with intuitive knowledge about natural phenomena and the last explains learning with use of computers. The theoretical frameworks were used to guide development of the simulation software and the intervention. The participants were 365 students in year five (10-11 year olds) and eight science teachers in Kuwait, located at eight different primary schools. All schools were single sex, with half the schools of each gender. All teachers were female. The study used a quasi-experimental design and separated the students into two experimental groups and two control groups. The first experimental group, which used simulations in computer labs, had 91 students in four primary schools (two boys’ and two girls’ schools). A matching control group with the same number of students was established in the same schools. The other experiment group had 92 students using simulations in the classroom. This group was also matched with an appropriate control group. The eight teachers taught both experimental and control group students. The control groups used traditional teaching. The experiment was carried out in the academic year 2010-2011. The study measured effects of the interventions with pre- and post achievement tests and attitude questionnaires. Students in the experimental groups also answered a usability questionnaire. A sub-sample of students and all teachers were interviewed for triangulation of the questionnaire data and to learn more about experiences with using the simulation software. The results of the study revealed no statistically significant difference (at the 0.05 level) in achievement or attitude between the students who used computer simulations in the computer laboratory. Students, however, who were taught with simulations in the classroom scored significantly higher on both achievement tests and attitude questionnaires. This benefit applied also to conceptual change of specific topics. In general, the interviews revealed that science teachers and students were satisfied with the simulation program used in science teaching and learning. However, the interviews indicated that there were some problems related to infrastructure and use of computers in the teaching that might have influenced the outcome of the study. These problems are relevant also to use of computer simulations in science teaching more widely.

A non-invasive, on-line method for detection of mechanical (rotor, bearings eccentricity) and stator winding faults in a 3-phase induction motors from observation of motor line current supply input. The main aim is to avoid the consequence of unexpected failure of critical equipment which results in extended process shutdown, costly machinery repair, and health and safety problems. This thesis looks into the possibility of utilizing machine learning techniques in the field of condition monitoring of electromechanical systems. Induction motors are chosen as an example for such application. Electrical motors play a vital role in our everyday life. Induction motors are kept in operation through monitoring its condition in a continuous manner in order to minimise their off times. The author proposes a model free sensor-less monitoring system, where the only monitored signal is the input to the induction motor. The thesis considers different methods available in literature for condition monitoring of induction motors and adopts a simple solution that is based on monitoring of the motor current. The method proposed use the feature extraction and Support Vector Machines (SVM) to set the limits for healthy and faulty data based on the statistical methods. After an extensive overview of the related literature and studies, the motor which is the virtual sensor in the drive system is analysed by considering its construction and principle of operation. The mathematical model of the motor is used for analysing the system. This is followed by laboratory testing of healthy motors and comparing their output signals with those of the same motors after being intentionally failed, concluding with the development of a full monitoring system. Finally, a monitoring system is proposed that can detect the presence of a fault in the monitored machine and diagnose the fault type and severity

This work has been carried out to extend on the interpretation of the Upper Crustal structure under the Eskdalemuir Seismic Array and the surrounding area. A study of the dispersion of short period (about 1 sec.) surface waves from local events at different distances and azimuths was considered, but the lack of events showing such waves turned attention to the study of first P-arrivals from the same sort of events. The thesis is in six chapters. Chapter I was given with an Introduction. In Chapter III the general aspects of the geology of the area were discussed very briefly. Previous seismic work around EKA was summarised with special reference to LOWNET and LISPB models. Seismic array technique, its advantages and methods of array data processing were discussed in Chapter III which also included a brief description of EKA and LOWNET and a detailed description of Broughton Array which was set up temporarily during the course of this work. Chapter IV gives detailed information about the data sources, origin time recording and play-back facilities. Preliminary results of the analysis of some EKA local events showed some systematic velocity and azimuth variations and this revealed the need for detailed information about the shallow structure under the array itself. Six shots were fired in the vicinity of EKA. Chapter V has been devoted for the presentation of the results of these shots, their discussion and interpretation. These demonstrated an anisotropy effect in the area of the array. Chapter VI presents the results of all local events, received at the three arrays, their discussion, comparison and interpretation. A velocity structure around EKA is proposed which involves (1) a rapid increase of velocity (0.8 km/sec./km) to about 1.6 km depth followed by a slow rate (< 0.003 km/sec./km) to an undefined depth (2) a variation in the initial (zero depth) velocity with azimuth ranging from 5.0 to 4.4 km/sec. parallel and normal to the Lower Palaeozoic strike respectively. The Broughton data were consistent with this model if the Lower Palaeozoic structure under the Midland Valley is essentially flat-lying. The extent to which these conclusions are consistent with previous work is discussed. Some of the methods of analysis are described in the Appendices (1 - 7), which also include two computer programs with their output results which form the basis for the interpretation and the above conclusions.