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Conceptualising the antecedents of employee intentions to transfer training to the job : an application of the Theory of Planned Behaviour in health education institutions
Get PDFThe study explores training transfer by utilising a socio-cognitive psychological theory, the theory of planned behaviour (Ajzen, 1991), to provide an understanding of the antecedents of participants' training transfer intention and behaviour. This theory claims that predictors of transfer can impact employees' transfer intention and behaviour through directly influencing their attitudes towards transfer, perceptions of subjective norms and their perceived behavioural control.;The empirical study gathers data from the perspective of faculty members and their supervisors within health education institutions in Oman. Semi-structured interviews were conducted with a total of 95 faculty members and their supervisors in two Health Institutes. The analysis explored participants' perceptions of training transfer within their Institutions and the factors that shaped their perceptions of subjective norms, perceived behaviour control and their attitudes towards training transfer.;The findings show that participants perceived opportunity to use trained skills in the workplace as an important factor to influence their transfer. Supervisors are the main referent group perceived to influence participants' transfer behaviour. Findings also show that recognition and resistance contributed towards participants' attitudes towards training transfer.;The theoretical contribution of the study is bridging the gap of understanding the training transfer process at the individual level by offering a holistic insight on training transfer behaviour within a specific context utilising the theory of planned behaviour. The study also has practical implications for organisations to plan and manage their training and transfer interventions to positively influence trainees' intention to transfer.The study explores training transfer by utilising a socio-cognitive psychological theory, the theory of planned behaviour (Ajzen, 1991), to provide an understanding of the antecedents of participants' training transfer intention and behaviour. This theory claims that predictors of transfer can impact employees' transfer intention and behaviour through directly influencing their attitudes towards transfer, perceptions of subjective norms and their perceived behavioural control.;The empirical study gathers data from the perspective of faculty members and their supervisors within health education institutions in Oman. Semi-structured interviews were conducted with a total of 95 faculty members and their supervisors in two Health Institutes. The analysis explored participants' perceptions of training transfer within their Institutions and the factors that shaped their perceptions of subjective norms, perceived behaviour control and their attitudes towards training transfer.;The findings show that participants perceived opportunity to use trained skills in the workplace as an important factor to influence their transfer. Supervisors are the main referent group perceived to influence participants' transfer behaviour. Findings also show that recognition and resistance contributed towards participants' attitudes towards training transfer.;The theoretical contribution of the study is bridging the gap of understanding the training transfer process at the individual level by offering a holistic insight on training transfer behaviour within a specific context utilising the theory of planned behaviour. The study also has practical implications for organisations to plan and manage their training and transfer interventions to positively influence trainees' intention to transfer
Investigation into the relationship between blunt impacts and bruising
Get PDFIncludes Appendix O on cd-rom.Bruising is an injury commonly observed within suspect cases of assault or abuse, however their interpretation is purely visual. Although the biology of bruising is known, how a blunt impact initiates bruising and influences its severity is not understood. Furthermore, the standard method of documenting bruising with colour photography is known to have limitations which in turn influence the already subjective analysis of bruise age and severity.Following ethical approval, this research aimed to address these problems through characterisation of a standardised blunt impact which was delivered to 18 volunteers. The resulting bruise was then imaged using 3 different photography techniques (colour, cross polarised (CP) and infrared (IR)) to determine if colour photography could be improved upon, whilst colour patterns using the L*a*b* colour model were taken from both colour and CP images to determine whether a measured colour timeline could be created to aid bruise age determination.Results showed that although no photography technique held any significant advantage over any other, CP provided greater image contrast than colour photography whilst IR imaging produced a clearer image of bruising over the initial stages of bruise formation. Although a general trend was seen for the measured colour patterns, they could not be characteristically attributed to any group of people, thus no colour timeline could be produced. Impact results demonstrated a characteristic tissue response which was strongly influenced by anthropometric features. These features also appeared to influence the severity of resultant bruising observed.It was concluded that both the photography and colour pattern methods assessed may not be the most appropriate for future research, whilst the potential variability of bruise severity between individuals was successfully visualised Therefore to gain a complete understanding of bruising, a detailed approach which combines impact, tissue response and the resulting bruise appearance is required.Bruising is an injury commonly observed within suspect cases of assault or abuse, however their interpretation is purely visual. Although the biology of bruising is known, how a blunt impact initiates bruising and influences its severity is not understood. Furthermore, the standard method of documenting bruising with colour photography is known to have limitations which in turn influence the already subjective analysis of bruise age and severity.Following ethical approval, this research aimed to address these problems through characterisation of a standardised blunt impact which was delivered to 18 volunteers. The resulting bruise was then imaged using 3 different photography techniques (colour, cross polarised (CP) and infrared (IR)) to determine if colour photography could be improved upon, whilst colour patterns using the L*a*b* colour model were taken from both colour and CP images to determine whether a measured colour timeline could be created to aid bruise age determination.Results showed that although no photography technique held any significant advantage over any other, CP provided greater image contrast than colour photography whilst IR imaging produced a clearer image of bruising over the initial stages of bruise formation. Although a general trend was seen for the measured colour patterns, they could not be characteristically attributed to any group of people, thus no colour timeline could be produced. Impact results demonstrated a characteristic tissue response which was strongly influenced by anthropometric features. These features also appeared to influence the severity of resultant bruising observed.It was concluded that both the photography and colour pattern methods assessed may not be the most appropriate for future research, whilst the potential variability of bruise severity between individuals was successfully visualised Therefore to gain a complete understanding of bruising, a detailed approach which combines impact, tissue response and the resulting bruise appearance is required
The 'crises in education' : children and counter-modernity in Hegel, Benjamin, Adorno, and Arendt
Get PDFThe trajectory of contemporary policy mandates and pedagogical practice demonstrates a strong inclination toward instrumental thinking. Troubling developments have met criticism from a variety of perspectives: psychological, empirical, and political. These are important challenges but an understanding of these diverse policies and practices as manifestations of the ways of thinking and being that characterise modernity allows for a fundamentally different type of critique, one which has the potential to transform those prejudices which support the continuing ascendency of instrumental reason. In the first half of the 20th Century German philosophers led the critique of modernity, which was rooted in the intellectual tradition of Hegel, Marx, Nietzsche, and Heidegger. The Frankfurt School of Critical Theory and its associates were preeminent. The published work included in this submission explores aspects of the individual theorists related to this school and considers the ways in which they challenge or illuminate current issues concerning the way we think about children and their education. The narrative is primarily a conceptual survey of the themes that connect these papers. It describes the salient features of modernity in relation to knowledge and subjectivity, and the counter-modern thinking that has existed concurrently with modern industrial capitalism. The aspect of counter-modernity that has particular potency for the various studies included in this submission is the notion of child as transgressive, avantgarde, irreverent, and enchanted. The idea of the enchanted child is neither romantic nor belittling, but instead allows for an understanding of childhood as a site of powerful oppositional enchantment that strikes at the modernist roots of instrumental thinking.The trajectory of contemporary policy mandates and pedagogical practice demonstrates a strong inclination toward instrumental thinking. Troubling developments have met criticism from a variety of perspectives: psychological, empirical, and political. These are important challenges but an understanding of these diverse policies and practices as manifestations of the ways of thinking and being that characterise modernity allows for a fundamentally different type of critique, one which has the potential to transform those prejudices which support the continuing ascendency of instrumental reason. In the first half of the 20th Century German philosophers led the critique of modernity, which was rooted in the intellectual tradition of Hegel, Marx, Nietzsche, and Heidegger. The Frankfurt School of Critical Theory and its associates were preeminent. The published work included in this submission explores aspects of the individual theorists related to this school and considers the ways in which they challenge or illuminate current issues concerning the way we think about children and their education. The narrative is primarily a conceptual survey of the themes that connect these papers. It describes the salient features of modernity in relation to knowledge and subjectivity, and the counter-modern thinking that has existed concurrently with modern industrial capitalism. The aspect of counter-modernity that has particular potency for the various studies included in this submission is the notion of child as transgressive, avantgarde, irreverent, and enchanted. The idea of the enchanted child is neither romantic nor belittling, but instead allows for an understanding of childhood as a site of powerful oppositional enchantment that strikes at the modernist roots of instrumental thinking
Essays on stock market openness, cost of capital and investment
Get PDFThis thesis examines the effects of stock market openness on the cost of equity capital and investment. Whilst theoretical models and extant empirical evidence suggest that emerging markets integration with global markets promotes risk sharing between domestic and foreign investors, reducing the cost of capital and increasing investments, other strands of research take a more critical stance, counter-arguing that integration is rather an imperfect process, with cost of capital benefits restricted to subsets of firms only, and that agency costs and weak levels of institutional development partially or fully impede gains from integration to be channeled to real investments. Motivated by this setup, this thesis contributes to the financial integration literature,in particular to the debate on the pros and cons of financial openness.;The first essay studies the relationship between stock market integration and the cost of equity capital, using Brazil as a case study. The paper also places particular emphasis on the role played by asset characteristics in the process of integration. Taking imperfect integration as theoretical underpinning, international asset pricing models are estimated for stocks' portfolios sorted by characteristics of size, book-to-market ratios, illiquidity, momentum, corporate governance and investability. Results show that stock market integration, as proxied by foreign stock ownership, reduces cost of equity capital, with larger benefits reaped by large caps, highly liquid stocks and strong governance firms. Results corroborate theoretical models of imperfectintegration, suggesting that integration brings beneficial effects on firms' funding costs.;In the second essay, the attention shifts to real economic effects of integration, with an investigationof the effects of stock market openness on corporate investment. Using a large sample offirms from 45 emerging and frontier markets, empirical investment models are estimated, employingdynamic panel data techniques. The analysis utilises two measures of stock openness, bothat country-level and at firm-level. At country-level, De Jure current-account openness indices,calculated by the International Monetary Fund are employed, whereas firm-specific De Factointegration is captured by foreign institutional stock ownership. Results suggest positive effectsof stock market openness on corporate investment, with findings remaining consistent across3both country and firm-level integration measures, and robust to endogeneity concerns. Strongereffects are found in countries with lower institutional development and higher expropriationrisks, consistent with the idea that the influx of foreign investors brings about improvements inmonitoring and governance standards. Results contribute important evidence that stock marketopenness, additionally to exerting positive effect on funding costs, also stimulates real economicactivity, by increasing firm-level investment.;The third and last essay escalates the analysis to the macroeconomic level. The relationship between foreign portfolio equity capital flows and domestic aggregate investment is investigated,paying attention again to the role of institutional quality in this relationship. Cross-country static and dynamic panel data models are estimated, for a sample of 44 emerging and frontier markets.Results at the macro level corroborate the findings obtained at micro level, with equity inflows associated to increases in domestic investment, measured both as gross capital formation and as the growth rate of domestic capital stock per capita. Again, effects are stronger in countries with lower institutional development, consistent with firm-level evidence. In summary, results show that integration effects spillover from micro to macro level, benefiting the whole domestic economy by expanding countries' capital stock.This thesis examines the effects of stock market openness on the cost of equity capital and investment. Whilst theoretical models and extant empirical evidence suggest that emerging markets integration with global markets promotes risk sharing between domestic and foreign investors, reducing the cost of capital and increasing investments, other strands of research take a more critical stance, counter-arguing that integration is rather an imperfect process, with cost of capital benefits restricted to subsets of firms only, and that agency costs and weak levels of institutional development partially or fully impede gains from integration to be channeled to real investments. Motivated by this setup, this thesis contributes to the financial integration literature,in particular to the debate on the pros and cons of financial openness.;The first essay studies the relationship between stock market integration and the cost of equity capital, using Brazil as a case study. The paper also places particular emphasis on the role played by asset characteristics in the process of integration. Taking imperfect integration as theoretical underpinning, international asset pricing models are estimated for stocks' portfolios sorted by characteristics of size, book-to-market ratios, illiquidity, momentum, corporate governance and investability. Results show that stock market integration, as proxied by foreign stock ownership, reduces cost of equity capital, with larger benefits reaped by large caps, highly liquid stocks and strong governance firms. Results corroborate theoretical models of imperfectintegration, suggesting that integration brings beneficial effects on firms' funding costs.;In the second essay, the attention shifts to real economic effects of integration, with an investigationof the effects of stock market openness on corporate investment. Using a large sample offirms from 45 emerging and frontier markets, empirical investment models are estimated, employingdynamic panel data techniques. The analysis utilises two measures of stock openness, bothat country-level and at firm-level. At country-level, De Jure current-account openness indices,calculated by the International Monetary Fund are employed, whereas firm-specific De Factointegration is captured by foreign institutional stock ownership. Results suggest positive effectsof stock market openness on corporate investment, with findings remaining consistent across3both country and firm-level integration measures, and robust to endogeneity concerns. Strongereffects are found in countries with lower institutional development and higher expropriationrisks, consistent with the idea that the influx of foreign investors brings about improvements inmonitoring and governance standards. Results contribute important evidence that stock marketopenness, additionally to exerting positive effect on funding costs, also stimulates real economicactivity, by increasing firm-level investment.;The third and last essay escalates the analysis to the macroeconomic level. The relationship between foreign portfolio equity capital flows and domestic aggregate investment is investigated,paying attention again to the role of institutional quality in this relationship. Cross-country static and dynamic panel data models are estimated, for a sample of 44 emerging and frontier markets.Results at the macro level corroborate the findings obtained at micro level, with equity inflows associated to increases in domestic investment, measured both as gross capital formation and as the growth rate of domestic capital stock per capita. Again, effects are stronger in countries with lower institutional development, consistent with firm-level evidence. In summary, results show that integration effects spillover from micro to macro level, benefiting the whole domestic economy by expanding countries' capital stock
Essays on global value chains
Get PDFThe past four decades have seen a large increase in trade via Global Value Chains (GVCs) as well as the relative demand for skilled labour. This thesis centres around the question how the former influences the latter. It firstly describes the large theoretical and empirical ambiguity that exists in the literature before proposing a novel graphical exposition of the channels by which GVCs affect the relative demand for skilled labour. This graph can synthesize the literature and show how small changes in microeconomic foundations can crucially alter predicted outcomes, greatly reducing theoretical ambiguity. It can also serve as a conceptual framework for empirical analysis which should remain the key method to analyse the research question.;Therefore, Chapters 2 and 3 employ micro and macro level data, respectively, and condition their results on the conclusions drawn from this conceptual framework. In line with that framework, this thesis finds that the relative skill abundance of the countries engaged in the GVC, which is used as a proxy for the factor bias of the GVC activity, crucially determines the results. On the other hand, the skill intensity of the sector that engages in GVCs does not seem to affect the results. This can best be interpreted in that GVCs allow (firms within) countries to specialise in their comparative advantage at an even more granular level than before, i.e. in the production of intermediate goods or tasks, rather than final goods.;Finally, Chapter 4, rather than looking at the effects of GVCs, looks at some of the causes. While formal tariffs have been going down, allowing the expansion of GVCs, non-tariff measures (NTMs) have increased. Chapter 4, however, finds that these NTMs do not significantly affect the export values of goods within that same value chain.The past four decades have seen a large increase in trade via Global Value Chains (GVCs) as well as the relative demand for skilled labour. This thesis centres around the question how the former influences the latter. It firstly describes the large theoretical and empirical ambiguity that exists in the literature before proposing a novel graphical exposition of the channels by which GVCs affect the relative demand for skilled labour. This graph can synthesize the literature and show how small changes in microeconomic foundations can crucially alter predicted outcomes, greatly reducing theoretical ambiguity. It can also serve as a conceptual framework for empirical analysis which should remain the key method to analyse the research question.;Therefore, Chapters 2 and 3 employ micro and macro level data, respectively, and condition their results on the conclusions drawn from this conceptual framework. In line with that framework, this thesis finds that the relative skill abundance of the countries engaged in the GVC, which is used as a proxy for the factor bias of the GVC activity, crucially determines the results. On the other hand, the skill intensity of the sector that engages in GVCs does not seem to affect the results. This can best be interpreted in that GVCs allow (firms within) countries to specialise in their comparative advantage at an even more granular level than before, i.e. in the production of intermediate goods or tasks, rather than final goods.;Finally, Chapter 4, rather than looking at the effects of GVCs, looks at some of the causes. While formal tariffs have been going down, allowing the expansion of GVCs, non-tariff measures (NTMs) have increased. Chapter 4, however, finds that these NTMs do not significantly affect the export values of goods within that same value chain
Exploring the utility of the ICF-CY (international classification functioning disability and health children and youth version) framework as a clinical reasoning tool for physiotherapists who treat children with Cerebal Palsy
Get PDFThree studies were conducted to explore the utility of the WHO taxonomy of health outcomes, namely the International Classification of Functioning Disability and Health, Children and Youth version (ICF-CY), as a Clinical Reasoning tool for Paediatric Physiotherapists (PPTs) treating children with Cerebral Palsy (CP) in Saudi Arabia. The first study was a systematic review to examine the integration of ICF knowledge into the clinical-thinking process in physiotherapy practice. All included articles utilised the ICF to identify ICF domains and apply it to the decision making process. However, only one paper examined the use of the ICF as a clinical-reasoning tool in physiotherapy practice. Contextual factors were often neglected in physiotherapist‟s decision making process. The second was a cross-sectional study that utilised a questionnaire based on psychological theory to explore the use of the ICF by PPTs in their clinical reasoning in relation to the management of children with CP. Results indicated PPTs with ICF knowledge consider environmental and personal factors in their decision-making when developing treatment plans. However, none of the cognitive constructs from the Theory of Planned Behaviour correlated with PPTs decision-making behaviour in the application of contextual factors.The third was a longitudinal Quasi-Experimental study that evaluated the impact of a two-day ICF-CY in-service training on PPTs‟ clinical reasoning and parental experience of the physiotherapy management of their child. The impact of training was significant on PPTs‟ knowledge of the ICF, performance and cognition including intention, attitude toward application and perceived control of the application of contextual factors. Parents were more satisfied with the treatment provided by ICF-trained group. However, there were no differences between the two groups of parents in their perceptions about the use of the ICF by PPTs. Findings from this dissertation inform the development of ICF-CY training as clinical reasoning tool for future studies to investigate ICF-CY implementation.Three studies were conducted to explore the utility of the WHO taxonomy of health outcomes, namely the International Classification of Functioning Disability and Health, Children and Youth version (ICF-CY), as a Clinical Reasoning tool for Paediatric Physiotherapists (PPTs) treating children with Cerebral Palsy (CP) in Saudi Arabia. The first study was a systematic review to examine the integration of ICF knowledge into the clinical-thinking process in physiotherapy practice. All included articles utilised the ICF to identify ICF domains and apply it to the decision making process. However, only one paper examined the use of the ICF as a clinical-reasoning tool in physiotherapy practice. Contextual factors were often neglected in physiotherapist‟s decision making process. The second was a cross-sectional study that utilised a questionnaire based on psychological theory to explore the use of the ICF by PPTs in their clinical reasoning in relation to the management of children with CP. Results indicated PPTs with ICF knowledge consider environmental and personal factors in their decision-making when developing treatment plans. However, none of the cognitive constructs from the Theory of Planned Behaviour correlated with PPTs decision-making behaviour in the application of contextual factors.The third was a longitudinal Quasi-Experimental study that evaluated the impact of a two-day ICF-CY in-service training on PPTs‟ clinical reasoning and parental experience of the physiotherapy management of their child. The impact of training was significant on PPTs‟ knowledge of the ICF, performance and cognition including intention, attitude toward application and perceived control of the application of contextual factors. Parents were more satisfied with the treatment provided by ICF-trained group. However, there were no differences between the two groups of parents in their perceptions about the use of the ICF by PPTs. Findings from this dissertation inform the development of ICF-CY training as clinical reasoning tool for future studies to investigate ICF-CY implementation
A blade design methodology for overspeed power regulation of horizontal axis tidal turbines
Get PDFEmployed in tidal turbines, overspeed power regulation (OSPR) can improve the structural robustness and decrease the complexity associated with active pitch methods, while removing the diffculties of operating in stalled flow. This may be a method by which the cost of tidal energy can be brought down. The aim of this research was to investigate the OSPR method, increase understanding of associated benefits and constraints, and develop a methodology for the design of suitable blades. It is identified that: the challenges to OSPR are higher rotational velocities, leading to increased voltage levels, an increased chance of cavitation on the rotor, and potentially detrimental thrust forces; these challenges may be best overcome with blade design alterations limiting the maximum rotational velocity.;The blade design methodology uses a design platform to set boundary conditions, an existing blade design as the base case, and a blade element momentum theory (BEMT) tool as the modelling method. Blade root pitch setting, twist and chord length distribution are the variable parameters investigated. A set of ospr performance metrics and a design space sensitivity analysis, with whole-blade cavitation analyses and diagnostic plots of torque and angle of attack, are used to ascertain how function-based and then precise blade design alterations affect rotor performance.;Tow tank tests defined base case rotor performance and verified the BEMT tool.Tests on the new blades allowed comparison to the base case test performance and to the BEMT prediction. Simulations showed that the new blade design regulated power without cavitation inception, without an increase in the thrust forces and with only a 3.6% drop in efficiency - as per the set boundary conditions and design requirements.The blade design methodology can be used to overcome challenges associated with overspeed and produce blades which give significant performance improvements for use in OSPR.Employed in tidal turbines, overspeed power regulation (OSPR) can improve the structural robustness and decrease the complexity associated with active pitch methods, while removing the diffculties of operating in stalled flow. This may be a method by which the cost of tidal energy can be brought down. The aim of this research was to investigate the OSPR method, increase understanding of associated benefits and constraints, and develop a methodology for the design of suitable blades. It is identified that: the challenges to OSPR are higher rotational velocities, leading to increased voltage levels, an increased chance of cavitation on the rotor, and potentially detrimental thrust forces; these challenges may be best overcome with blade design alterations limiting the maximum rotational velocity.;The blade design methodology uses a design platform to set boundary conditions, an existing blade design as the base case, and a blade element momentum theory (BEMT) tool as the modelling method. Blade root pitch setting, twist and chord length distribution are the variable parameters investigated. A set of ospr performance metrics and a design space sensitivity analysis, with whole-blade cavitation analyses and diagnostic plots of torque and angle of attack, are used to ascertain how function-based and then precise blade design alterations affect rotor performance.;Tow tank tests defined base case rotor performance and verified the BEMT tool.Tests on the new blades allowed comparison to the base case test performance and to the BEMT prediction. Simulations showed that the new blade design regulated power without cavitation inception, without an increase in the thrust forces and with only a 3.6% drop in efficiency - as per the set boundary conditions and design requirements.The blade design methodology can be used to overcome challenges associated with overspeed and produce blades which give significant performance improvements for use in OSPR
Atmospheric correction and anomaly detection of remotely sensed hyperspectral imagery
Get PDFThe work presented in this thesis focuses on improving the anomaly detection process for remotely sensed hyperspectral imagery. This process is split up into three main sections; data reduction, atmospheric correction and anomaly detection. The final stage of this anomaly detection process is the actual anomaly detection algorithm. The initial contribution looks at developing a new type of anomaly detection algorithm based on the Percentage Occupancy Hit-or-Miss Transform. Also, a process for trying to improve the existing Mahalanobis Distance technique for hyperspectral data is explained. Both techniques are then tested on two aerial hyperspectral images, and the results are compared with an established technique the Sequential Maximum Angle Convex Cone algorithm. One of the preprocessing steps of the anomaly detection process is the atmospheric correction phase. In this thesis an interface is developed in MATLAB for the atmospheric modelling software MODTRAN, this interface is then used to find the key parameters that have the most effect on the atmospheric models produced. Having determined the key parameters of a MODTRAN atmospheric model, the models are then used to atmospherically correct eight hyperspectral images; four visible to near-infrared and four short wave infrared hyperspectral images. Two scene based approaches for atmospheric correction are also proposed that use known spectra extracted from the scene to produce an atmospheric transform. All three techniques are then evaluated against existing scene-based approaches, namely Internal Average Relative Reflectance and Dark Object Subtraction. The final contribution focuses on the data reduction phase, images of a wind turbine blade with simulated erosion were taken using a near-infrared hyperspectral camera. By analysing the images produced it was possible to determine the optimal bands necessary to detect each type of erosion. The greyscale images produced for the optimal bands were then compared with standard RGB camera imaging to determine if any more detail was shown in the hyperspectral images. Also by imaging the blade at varying light levels, it was possible to determine when this technique breaks down, however by performing some post-processing of the new data using a polynomial surface subtraction to flatten the images it was again possible to extract additional information from the hyperspectral images.The work presented in this thesis focuses on improving the anomaly detection process for remotely sensed hyperspectral imagery. This process is split up into three main sections; data reduction, atmospheric correction and anomaly detection. The final stage of this anomaly detection process is the actual anomaly detection algorithm. The initial contribution looks at developing a new type of anomaly detection algorithm based on the Percentage Occupancy Hit-or-Miss Transform. Also, a process for trying to improve the existing Mahalanobis Distance technique for hyperspectral data is explained. Both techniques are then tested on two aerial hyperspectral images, and the results are compared with an established technique the Sequential Maximum Angle Convex Cone algorithm. One of the preprocessing steps of the anomaly detection process is the atmospheric correction phase. In this thesis an interface is developed in MATLAB for the atmospheric modelling software MODTRAN, this interface is then used to find the key parameters that have the most effect on the atmospheric models produced. Having determined the key parameters of a MODTRAN atmospheric model, the models are then used to atmospherically correct eight hyperspectral images; four visible to near-infrared and four short wave infrared hyperspectral images. Two scene based approaches for atmospheric correction are also proposed that use known spectra extracted from the scene to produce an atmospheric transform. All three techniques are then evaluated against existing scene-based approaches, namely Internal Average Relative Reflectance and Dark Object Subtraction. The final contribution focuses on the data reduction phase, images of a wind turbine blade with simulated erosion were taken using a near-infrared hyperspectral camera. By analysing the images produced it was possible to determine the optimal bands necessary to detect each type of erosion. The greyscale images produced for the optimal bands were then compared with standard RGB camera imaging to determine if any more detail was shown in the hyperspectral images. Also by imaging the blade at varying light levels, it was possible to determine when this technique breaks down, however by performing some post-processing of the new data using a polynomial surface subtraction to flatten the images it was again possible to extract additional information from the hyperspectral images
Directional hearing at the micro-scale : bio-inspired sound localization
Get PDFMiniaturization of sound localization sensors arrays is heavily constrained by the limited directional cues in intensity difference and phase difference available at the microscale. Micro-Electro Mechanical System (MEMS) sound localization sensors inspired by the auditory system of Ormia ochracea offer a potential solution to this problem by the apparent amplification of the available intensity and phase difference between the measurement points. An inherent limitation of these systems is that significant amplification of these cues is only available on or near one of the resonant frequencies of the device, severely limiting it [sic] application as a directional microphone. A lower amplification of directional cues can be achieved across a wide frequency range, forcing designers to compromise the goal of high amplification of directional cues to operate across the audio range. Here we present an alternative approach, namely a system optimized for the maximum amplification of directional cues across a narrow bandwidth operating purely as a sound localization sensor for wide-band noise. In the devices presented in chapter four we present sound-localization sensors where the directional sensitivity is enhanced by increasing the coupling strength beyond the 'dual optimization' point, which represents the collocation of a local maximum in directional sensitivity and a local minimum in non-linearity, compensating for the loss of the desirable linearity of the system by restricting the angular range of operation. Intensity gain achieved is 16.3 dB at 10° sound source azimuth with a linear directional sensitivity of 1.6 dB per degree, while linear directional sensitivity in phase difference gain shows a seven fold increase over the 'dual optimization' point of 8 degrees per degree. In addition, during the course of this work it was discovered that the methods used to calculate the amplified intensity difference between the measurement points introduce unwelcome Cauchy noise which is difficult to reduce. Later iterations of the device demonstrate the process of optimization of a sound localization sensor for the maximum amplification of directional cues across a narrow bandwidth can be used to overcome that error, as well as describing mathematically what appears to have been a commonly encountered but unpublished problem with Ormia inspired directional sensors. In the second part of the thesis, beginning in Chapter 5 the sound localization strategies of another acoustic insect, the lesser wax moth Achroia grisella, is examined. Moths differ somewhat because their ears generally function as simple bat detectors with relatively little directional ability. Those moths that use sound signals for mating communication represent a yet more special case, as these species can localize sound sources but singing and the ability to localize conspecific song evolved well after the origin of hearing. The analyses revealed a novel localization mechanism wherein the geometry and structure of the tympanal membrane of each ear afford sharp sensitivity to sound arriving from a distinct angle. Females can thereby track singing males, but they only do so by following an indirect, curvilinear trajectory regularly interrupted by wide deviations.Miniaturization of sound localization sensors arrays is heavily constrained by the limited directional cues in intensity difference and phase difference available at the microscale. Micro-Electro Mechanical System (MEMS) sound localization sensors inspired by the auditory system of Ormia ochracea offer a potential solution to this problem by the apparent amplification of the available intensity and phase difference between the measurement points. An inherent limitation of these systems is that significant amplification of these cues is only available on or near one of the resonant frequencies of the device, severely limiting it [sic] application as a directional microphone. A lower amplification of directional cues can be achieved across a wide frequency range, forcing designers to compromise the goal of high amplification of directional cues to operate across the audio range. Here we present an alternative approach, namely a system optimized for the maximum amplification of directional cues across a narrow bandwidth operating purely as a sound localization sensor for wide-band noise. In the devices presented in chapter four we present sound-localization sensors where the directional sensitivity is enhanced by increasing the coupling strength beyond the 'dual optimization' point, which represents the collocation of a local maximum in directional sensitivity and a local minimum in non-linearity, compensating for the loss of the desirable linearity of the system by restricting the angular range of operation. Intensity gain achieved is 16.3 dB at 10° sound source azimuth with a linear directional sensitivity of 1.6 dB per degree, while linear directional sensitivity in phase difference gain shows a seven fold increase over the 'dual optimization' point of 8 degrees per degree. In addition, during the course of this work it was discovered that the methods used to calculate the amplified intensity difference between the measurement points introduce unwelcome Cauchy noise which is difficult to reduce. Later iterations of the device demonstrate the process of optimization of a sound localization sensor for the maximum amplification of directional cues across a narrow bandwidth can be used to overcome that error, as well as describing mathematically what appears to have been a commonly encountered but unpublished problem with Ormia inspired directional sensors. In the second part of the thesis, beginning in Chapter 5 the sound localization strategies of another acoustic insect, the lesser wax moth Achroia grisella, is examined. Moths differ somewhat because their ears generally function as simple bat detectors with relatively little directional ability. Those moths that use sound signals for mating communication represent a yet more special case, as these species can localize sound sources but singing and the ability to localize conspecific song evolved well after the origin of hearing. The analyses revealed a novel localization mechanism wherein the geometry and structure of the tympanal membrane of each ear afford sharp sensitivity to sound arriving from a distinct angle. Females can thereby track singing males, but they only do so by following an indirect, curvilinear trajectory regularly interrupted by wide deviations
The effects of JNK isoform knockdown on cell growth and death in HUVECs and MCF-7 cells
Get PDFCardiovascular disease (CVD) and cancer are two of the leading causes of mortality worldwide. The JNK pathway has been shown to play key roles at various stages of both of these diseases and therefore is an important protein to try and understand. In animal models of atherosclerosis and breast cancer, inhibition of JNK has been demonstrated to reduce pathogenesis and therefore targeting this protein may be key for developing treatments. JNK exists as three individual proteins, JNK1, JNK2 and JNK3 and studies are now showing that not only can these proteins work independently but also opposingly in some instances and therefore understanding the function of the individual isoforms is becoming critical to fully understanding this pathway. Although more research is focusing on JNK isoform function, characterisation of each JNK protein has not yet been carried out in human primary vascular cells or a human breast cancer cell line, an investigation which must be carried out to understand the role of this pathway in the pathogenesis of these diseases. In the current study lentiviral shRNA was used to target and knockdown JNK1 and JNK2 in both human umbilical vein endothelial cells (HUVECs) and MCF-7 breast cancer cells and the effects of knockdown on cell growth and cell death processes were analysed. In HUVECs knockdown of JNK2 caused an increase in pc-Jun levels and an increase in the percentage of multinucleated cells was observed, suggesting JNK2 may play a role in HUVEC cell growth. Unfortunately, the lentiviral infection itself caused detrimental effects which made it difficult to continue experiments and explore these findings further. In MCF-7 cells JNK knockdown did not produce any changes in cell growth or induced cell death when compared to non-target controls, suggesting that JNK does not play a key role in this breast cancer cell line.Cardiovascular disease (CVD) and cancer are two of the leading causes of mortality worldwide. The JNK pathway has been shown to play key roles at various stages of both of these diseases and therefore is an important protein to try and understand. In animal models of atherosclerosis and breast cancer, inhibition of JNK has been demonstrated to reduce pathogenesis and therefore targeting this protein may be key for developing treatments. JNK exists as three individual proteins, JNK1, JNK2 and JNK3 and studies are now showing that not only can these proteins work independently but also opposingly in some instances and therefore understanding the function of the individual isoforms is becoming critical to fully understanding this pathway. Although more research is focusing on JNK isoform function, characterisation of each JNK protein has not yet been carried out in human primary vascular cells or a human breast cancer cell line, an investigation which must be carried out to understand the role of this pathway in the pathogenesis of these diseases. In the current study lentiviral shRNA was used to target and knockdown JNK1 and JNK2 in both human umbilical vein endothelial cells (HUVECs) and MCF-7 breast cancer cells and the effects of knockdown on cell growth and cell death processes were analysed. In HUVECs knockdown of JNK2 caused an increase in pc-Jun levels and an increase in the percentage of multinucleated cells was observed, suggesting JNK2 may play a role in HUVEC cell growth. Unfortunately, the lentiviral infection itself caused detrimental effects which made it difficult to continue experiments and explore these findings further. In MCF-7 cells JNK knockdown did not produce any changes in cell growth or induced cell death when compared to non-target controls, suggesting that JNK does not play a key role in this breast cancer cell line
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