Transforming health professionals into population health change agents

Background. With the recognition that professional education has not kept pace with the challenges facing the health and human service system, there has been a move to transformative education and learning professional development designed to expand the number of enlightened and empowered change agents with the competence to implement changes at an individual, organisation and systems level. Design and Methods. Since 2010, the Department of Health and Human Services in Victoria, Australia, in collaboration with The University of Melbourne’s School of Population and Global Health, has delivered seven population health short courses aimed to catalyse participants’ transformation into population health change agents. This paper presents key learnings from a combination of evaluation data from six population health short courses using a transformative learning framework from a 2010 independent international commission for health professionals that was designed to support the goals of transformative and interdependent health professionals. Participatory realist evaluation approaches and qualitative methods were used. Results. Evaluation findings reveal that there were mixed outcomes in facilitating participants’ implementation of population health approaches, and their transformation into population health agents upon their return to their workplaces. Core enablers, barriers and requirements, at individual, organisational and system levels influence the capability of participants to implement population health approaches. The iterative and systemic evolution of the population health short courses, from a one off event to a program of inter-dependent modules, demonstrates sustained commitment by the short course developers and organisers to the promotion of transformative population health learning outcomes. Conclusions: To leverage this commitment, recognising that professional development is not an event but part of an ongoing transformative process, suggestions to further align recognition of population health professional development programs are presented

Single ion detection using FET based nano-sensors: a combined drift diffusion and Brownian dynamics 3D simulation study

There is an ever increasing requirement for rapid sensing mechanisms for a variety of purposes – from blood analysis to gas detection. In order to allow large throughput, these devices must also be available at low cost per unit. One method which meets these criteria is the interfacing of biological and nano-scale semiconductor elements. Using modern CMOS processing, alongside further post processing, such devices can be created for a variety of purposes. However, development of these devices is expensive and in order to investigate possible structures, a simulation system is ideal. This work details the development, testing and utilisation of such a system. By combining two widely understood simulation methods – Brownian dynamics and drift diffusion – a mix of efficiency and accuracy is achieved. The introduction begins with a section detailing background to the field in order to set the work in context. The development and strict testing regime employed is then described. Initial simulations of a bio-nano interface are then presented with detection of ions though alterations in the drain current of a nominal 35 nm FET. This shows that there is a 5 nA/µm increase in drain current when an ion is moved through a 3 nm lipid layer which is suspended 15 nm above the oxide allowing identification of the period of traversal of the lipid layer. The final chapter indicates the successful detection of individual ions traversing a nano-pore in the presence of biologically significant ionic concentrations. The rate of change of drain current in the FET indicates a 4 σ signal during traversal with a background concentration of ions of 1 mM which allows clear identification of this individual event

Design and optimisation of solar sail orbits in proximity of asteroids

A solar sail is a large reflective membrane which is capable of producing thrust for a spacecraft by the reflection of sunlight. Such a propellant-less propulsion system can offer solutions to high-energy missions which would be impossible for conventional propulsion systems. As a result, this technology has been proposed by many authors as the ideal candidate for a multiple asteroid rendezvous mission. At the time of writing, there are more than 30,000 known near-Earth asteroids (NEAs) alone. Adding to this those contained in the main belt and elsewhere in the solar system, the abundance of these small rocky worlds becomes apparent. Focusing only on the NEAs, there are many reasons for interest in missions to these bodies. In the first instance, they represent the earliest building blocks of the rocky worlds of the solar system, and are often still in pristine condition, similar to how they would have been since these earliest moments. As such, there is massive scientific interest in visiting and extracting samples of their constituent materials. There is another community which is also interested in the extraction of these materials: the future asteroid miners. This mining could provide propellant for deep space missions, materials for in-space infrastructure and potentially also in the return of minerals which are rare on Earth, and so of great value. However, although these bodies provide many opportunities, they are not without threat. Although the frequency of impacts of large bodies capable of causing considerable damage to Earth-based infrastructure is relatively low, there are still recent examples of just such events. With the potential for large scale loss of life due to an asteroid impacting populated areas, the science of planetary defence requires greater knowledge of the make-up of these bodies. Yet another reason for mission designers to examine further options in achieving efficient missions to these bodies. It would be beneficial, in terms of cost, for a single spacecraft to be able to carry out a mission to multiple asteroids. Such a high-energy mission is ideally suited to the solar sail. Although the literature has provided many works on orbital transfers to multiple bodies, the operation of the sail when in proximity of the asteroid has not received quite as much attention. It is in this phase of the mission, where the science objectives would be carried out, that this thesis focuses. There are numerous challenges which the sail faces in the near-asteroid environment. These include the irregular gravity field, the strength of the acceleration provided by the sail in a relatively weak gravitational field, the often fast rotational velocities of the asteroid and higher demands on slew rates for the sail due to the shorter period of low-altitude orbits. The work will consider three main proximity phases. The first operation is in the control of an orbit using the solar sail in an irregular gravity field. In this operation, the sail must counter the perturbative effects of a non-spherical body. This manifests in the rotation of the orbit node line, referred to as nodal regression. A new tool, referred to as the Control Transition Matrix (CTM), which aids in forcing a periodic orbit solution over multiple orbits is then presented. The second operation deals with the control of a sail at the point of and subsequent to the deployment of a lander and during the deployment of a series of small ChipSat probes. The landing conditions for deployments from various locations around the asteroid are analysed before the deployment is presented from a low-asteroid orbit. The control of the sail along a nominal orbit while the lander is still on-board is presented before the sail control subsequent to the lander deployment is considered. Given the high velocity impacts for a ballistic lander deployed at large distances from the surface, an alternative mission scenario of the deployment of small ChipSat probes is presented. These probes are envisaged to carry out their science goals during the descent and so the landing conditions are less important. The final operation is in the gravitational capture of the sail around the asteroid. This work provides a preliminary analysis of the capability of the sail in achieving this by using a simple on/off control law. Following this, a more detailed two-phase approach is presented. In the first “initial capture” phase, the sail uses the value of Jacobi constant in the 3 body system as a guide to reduce the orbit radius to within a defined region. After this, the “orbit shaping” phase aims to circularise the orbit at this radius. Subsequently, preliminary investigations into an optimal approach are presented. In controlling the effects due to the non-spherical asteroid shape, an optimally controlled solution, where a minimum effort control law is sought, is presented. Following this, a novel method of updating a control law was successfully applied to force a periodic orbit. In the work carried out on lander deployment, it was found that the sail was capable of maintaining a periodic orbit after the point of lander separation by application of time-delay feedback control. For the deployment of a series of small probes, it was found that maintaining a fixed attitude for the sail during the deployment was not considerably different in station-keeping performance compared with LQR control, and performed this with no effort required of the sail. Finally, in the work on capture, the two-phase approach provided successful capture trajectories down to the desired orbit radius. The work showed that, for reducing size of asteroid, there was a reduction in the time to capture. This is due to the fact that the same size of sail is used in the weakening gravity field of each asteroid. This makes the sail relatively more powerful and so able to affect quicker capture. It was also seen that long period capture trajectories are compounded by the need for the sail to spend periods of time waiting for the position of the Sun relative to the orbit to be in such a way as to permit the capture operations to proceed. There was also the successful demonstration of an optimally controlled capture which minimised the orbit semi-parameter over one orbit revolution. The work contained in this thesis provides preliminary analysis for the consideration of future solar sail mission designers in the proximity operations of a sail near an asteroid. The findings presented here have shown that the sail can be of considerable utility in these proximity operations. They also present challenges to the mission designer given the continuous thrust that they may provide. Where a powerful sail may benefit the interplanetary phase of a mission in reaching many more asteroids further from the Earth, this can also present a challenge in the relatively weak asteroid gravitational field. However, these challenges are not insurmountable and so the sail remains a promising option for these high-energy missions

The 2005 AMI system for the transcription of speech in meetings

In this paper we describe the 2005 AMI system for the transcription\ud of speech in meetings used for participation in the 2005 NIST\ud RT evaluations. The system was designed for participation in the speech\ud to text part of the evaluations, in particular for transcription of speech\ud recorded with multiple distant microphones and independent headset\ud microphones. System performance was tested on both conference room\ud and lecture style meetings. Although input sources are processed using\ud different front-ends, the recognition process is based on a unified system\ud architecture. The system operates in multiple passes and makes use\ud of state of the art technologies such as discriminative training, vocal\ud tract length normalisation, heteroscedastic linear discriminant analysis,\ud speaker adaptation with maximum likelihood linear regression and minimum\ud word error rate decoding. In this paper we describe the system performance\ud on the official development and test sets for the NIST RT05s\ud evaluations. The system was jointly developed in less than 10 months\ud by a multi-site team and was shown to achieve very competitive performance

Small Microphone Array: Algorithms and Hardware

This report describes the processing algorithms and gives an overview of the hardware for the small microphone array unit in the IM2.RTMAP (Real-time Microphone Array Processing) project. The algorithms include techniques for speech enhancement, speaker localisation and speaker segmentation. The hardware consists of a DSP platform with 8 audio inputs and outputs, as well as a Fireware interface for communication with a PC or other modules

Microphone Array Speech Recognition : Experiments on Overlapping Speech in Meetings

This paper investigates the use of microphone arrays to acquire and recognise speech in meetings. Meetings pose several interesting problems for speech processing, as they consist of multiple competing speakers within a small space, typically around a table. Due to their ability to provide hands-free acquisition and directional discrimination, microphone arrays present a potential alternative to close-talking microphones in such an application. We first propose an appropriate microphone array geometry and improved processing technique for this scenario, paying particular attention to speaker separation during possible overlap segments. Data collection of a small vocabulary speech recognition corpus (Numbers) was performed in a real meeting room for a single speaker, and several overlapping speech scenarios. In speech recognition experiments on the acquired database, the performance of the microphone array system is compared to that of a close-talking lapel microphone, and a single table-top microphone

Practical teaching in secondary level certificated physics : a view from Scotland

This study reports on a survey conducted in the Scottish physics education context focusing on practical work within National 5 certificated classes. The online survey was open to all practising educators and technicians in Scotland's secondary schools and further education colleges. Descriptive statistics were used to analyse the results, alongside basic thematic analysis of text responses. The results indicate a decline in practical work in the classroom but suggests this is not due to the COVID-19 pandemic. Instead, cost and availability of equipment alongside a perceived lack of time for experimental work are cited as the major difficulties. The resulting recommendations are improvements to the curriculum and support for educators to develop best practice

Asteroid Landing With a Solar Sail: Lander Deployment and Sail Descent to Surface

A critical phase of any mission which aims to interact with the surface of an asteroid is in landing. This can be done via landing of the main spacecraft, or by the deployment of separate landers. In this work, the spacecraft will be propelled by a solar sail. The solar sail is capable of delivering high energy missions, given the unlimited momentum available from the Sun. The performance of the sail is dependent on the area to mass ratio of the sail/spacecraft combination. The separation of a significant mass from the main spacecraft will result in a change in performance of the solar sail. This changing performance will affect the dynamics of the solar sail in the near-asteroid environment. This work will investigate the effects of the solar sail in the dynamics of the near asteroid space, as well as the instantaneous change of dynamics at lander separation. Then, work will show the deployment of a lander from various regions of the problem, providing a probability analysis of the success of the lander reaching the surface with a ballistic deployment from each region. Deployment from the region interior to the potential ridge line is found to have the greatest success