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The aims of the research for this thesis were fourfold, all of which focused at reducing employee exposure to diesel particulate in underground coal mines. The four aims were to: a) Develop a method to test disposable diesel exhaust filters and if possible improve their performance b) Investigate the relationship between maintenance and diesel particulate generation c) Highlight the benefits of newer design engines in emission reduction d) Review the research of the Tower Colliery Research group as their findings have been the basis for the development of control technologies for diesel particulate in NSW underground coal mines. Methods used to achieve these aims involved: a) The construction of a test rig to measure the efficiency and backpressure of new and used disposable filters b) The testing of the in service fleet at four of BHP Billiton Illawarra Coal mines using an R&P Series 5100 diesel analysis system mounted in a trailer c) Comparison of a newer design engine with three current vehicles under mining conditions d) A detailed statistical review of all available data from the Tower Colliery Research group. Key outcomes from research conducted for this thesis are: a) The filtration efficiency and backpressure of disposable diesel exhaust filters used by BHP Billiton Illawarra Coal have been improved. These improvements, together with changes to work practices, generate potential cost savings of $395,000 per annum while affording increased protection to equipment operators. b) Seven engines with unacceptable raw exhaust elemental carbon emissions were identified in a fleet of 66 tested. Some faults identified as causing these elevated emission levels were- blocked exhaust flame traps (scrubber tanks), incorrectly set tappets and worn injectors. c) Testing of a prototype 4WD fire protected vehicle powered by an "over the road" engine as against three current vehicles, highlighted reductions in atmospheric elemental carbon concentrations of 67 90%. Significant reductions in raw exhaust elemental carbon levels were also observed. d) A statistical review of data produced by the Tower Colliery Diesel Research group identified elevated exposures within mine transportation roadways. This outcome is significant as much research within the mining industry has focused on other areas in the belief that high air quantities in transportation roadways would limit exposures. This does not appear to be the case. The project has had a number of positive outcomes, all of which have assisted in the reduction of equipment operators to excessive levels of diesel particulate.

Percutaneous intervention is a common type of minimally invasive procedure used to treat and diagnose many disorders. Typically, the needle used is rigid and straight and therefore requires a straight-line path to the target. Problems though arise in complex scenarios, where there is a narrow region the needle must travel through while avoiding critical tissue. As the tissue deforms, the needle may need to be reinserted to achieve the correct path, increasing the risk of tissue trauma. Needle steering aims to solve this, as well as enable procedures that would otherwise not be possible. Within this context, this thesis describes the development of less intrusive control schemes for a novel biologically inspired needle steering system codenamed STING. This thesis presents several research contributions to needle steering, which advance the STING needle towards clinical use. A characterisation of the steering behaviour in three dimensions was performed, which demonstrates the ability of the multi-segment design to follow curvilinear paths through planar movements in full three dimensions. A planar on-line path planning method and constrained closed-loop controller were proposed that allow the needle to be used in dynamic, multi-target environments. Experimental validation through one and two moving targets scenarios demonstrated the STING's multi-targeting capabilities, and a reduction in the placement error compared to the existing literature. Finally, a cyclic actuation control scheme was developed, with the aim of reducing tissue motion arising due to the insertion process. in vitro validation of the scheme within gelatine tissue phantoms demonstrated no increase in error over standard actuation methods, but a significant reduction in tissue deformation. A reduction of the outside diameter of the STING needle from 12mm to 2.5mm was also achieved within this work, culminating in a clinically viable prototype. The thesis concludes with a summary of the research and suggestions for future work.

Hands-on robotic surgery is where the surgeon controls the tool's motion by applying forces and torques to the robot holding the tool, allowing the robot-environment interaction to be felt though the tool itself. To further improve results, shared control strategies are used to combine the strengths of the surgeon with those of the robot. One such strategy is active constraints, which prevent motion into regions deemed unsafe or unnecessary. While research in active constraints on rigid anatomy has been well-established, limited work on dynamic active constraints (DACs) for deformable soft tissue has been performed, particularly on strategies which handle multiple sensing modalities. In addition, attaching the tool to the robot imposes the end effector dynamics onto the surgeon, reducing dexterity and increasing fatigue. Current control policies on these systems only compensate for gravity, ignoring other dynamic effects. This thesis presents several research contributions to shared control in hands-on robotic surgery, which create a more natural motion for the surgeon and expand the usage of DACs to point clouds. A novel null-space based optimization technique has been developed which minimizes the end effector friction, mass, and inertia of redundant robots, creating a more natural motion, one which is closer to the feeling of the tool unattached to the robot. By operating in the null-space, the surgeon is left in full control of the procedure. A novel DACs approach has also been developed, which operates on point clouds. This allows its application to various sensing technologies, such as 3D cameras or CT scans and, therefore, various surgeries. Experimental validation in point-to-point motion trials and a virtual reality ultrasound scenario demonstrate a reduction in work when maneuvering the tool and improvements in accuracy and speed when performing virtual ultrasound scans. Overall, the results suggest that these techniques could increase the ease of use for the surgeon and improve patient safety.

Current trends in surgical intervention favour a minimally invasive (MI) approach, in which complex procedures are performed through increasingly small incisions. Specifically, in neurosurgery, there is a need for minimally invasive keyhole access, which conflicts with the lack of maneuverability of conventional rigid instruments. In an attempt to address this fundamental shortcoming, this thesis describes the concept design, implementation and experimental validation of a novel flexible and steerable probe, named “STING” (Soft Tissue Intervention and Neurosurgical Guide), which is able to steer along curvilinear trajectories within a compliant medium. The underlying mechanism of motion of the flexible probe, based on the reciprocal movement of interlocked probe segments, is biologically inspired and was designed around the unique features of the ovipositor of certain parasitic wasps. Such insects are able to lay eggs by penetrating different kinds of “host” (e.g. wood, larva) with a very thin and flexible multi-part channel, thanks to a micro-toothed surface topography, coupled with a reciprocating “push and pull” motion of each segment. This thesis starts by exploring these foundations, where the “microtexturing” of the surface of a rigid probe prototype is shown to facilitate probe insertion into soft tissue (porcine brain), while gaining tissue purchase when the probe is tensioned outwards. Based on these findings, forward motion into soft tissue via a reciprocating mechanism is then demonstrated through a focused set of experimental trials in gelatine and agar gel. A flexible probe prototype (10 mm diameter), composed of four interconnected segments, is then presented and shown to be able to steer in a brain-like material along multiple curvilinear trajectories on a plane. The geometry and certain key features of the probe are optimised through finite element models, and a suitable actuation strategy is proposed, where the approach vector of the tip is found to be a function of the offset between interlocked segments. This concept of a “programmable bevel”, which enables the steering angle to be chosen with virtually infinite resolution, represents a world-first in percutaneous soft tissue surgery. The thesis concludes with a description of the integration and validation of a fully functional prototype within a larger neurosurgical robotic suite (EU FP7 ROBOCAST), which is followed by a summary of the corresponding implications for future work.

Current legislation requires schools in England and Wales to promote the spiritual development of their pupils. The non-statutory guidance provided by various bodies has resulted in broad and inclusive definitions of the ‘spiritual’ and ‘spiritual development’ which combines both the religious and the secular and applies to all areas of the curriculum and school life. The world of academia has responded to this quasi-official guidance with varying degrees of approval to downright hostility, exposing the pretence that all agree with the current definitions and guidance. This thesis examines, by means of a cross-sectional survey, using qualitative and quantitative data gathered by means of questionnaire and interview, the perceptions of a sample of student teachers (428) on teacher training courses and qualified teachers (76) of the meanings of 'spirituality', 'spiritual experience' and 'spiritual development'. Although different viewpoints emerge, some underlying themes can be discerned. 'Spirituality' is conceived as the acquisition of a set of principles to guide everyday living, which may be derived from a religion, from a personal philosophy or from beliefs concerning morality, relationships with others, and an increased awareness of life and the world. The 'spiritual development' of pupils is seen to imply their freedom to search for and decide the principles they will adopt. The views of respondents on the extent to which 'spiritual development' should form part of the teacher's role are also reported, and it is suggested that current terminology associated with ‘spirituality’ be replaced with terms which students and teachers can more readily understand.

This thesis examines the relation between classical and quantum mechanics from philosophical, mathematical and physical standpoints. It first presents arguments in support of "conjectural realism" in scientific theories distinguished by explicit contextual structure and empirical testability; and it analyses intertheoretic reduction in terms of weakly equivalent theories over a domain of applicability. Familiar formulations of classical and quantum mechanics are shown to follow from a general theory of mechanics based on pure states with an intrinsic probability structure. This theory is developed to the stage where theorems from quantum logic enable expression of the state geometry in Hilbert space. Quantum and classical mechanics are then elaborated and applied to subsystems and the measurement process. Consideration is also given to spacetime geometry and the constraints this places on the dynamics. Physics and Mathematics, it is argued, are growing apart; the inadequate treatment of approximations in general and localization in quantum mechanics in particular are seen as contributing factors. In the description of systems, the link between localization and lack of knowledge shows that quantum mechanics should reflect the domain of applicability. Restricting the class of states provides a means of achieving this goal. Localisation is then shown to have a mathematical expression in terms of compactness, which in tum is applied to yield a topological theory of bound and scattering states: Finally, the thesis questions the validity of "classical limits" and "quantisations" in intertheoretic reduction, and demonstrates that a widely accepted classical limit does not constitute a proof of reduction. It proposes a procedure for determining whether classical and quantum mechanics are weakly equivalent over a domain of applicability, and concludes that, in this restricted sense, classical mechanics reduces to quantum mechanics.