The objective of this Master's thesis was to design and implement a low power Analog to Digital Converter (ADC) used for sensor measurements. In the complete measurement unit, in which the ADC is part of, different sensors will be measured. One set of these sensors are three strain gauges with weak output signals which are to be pre-amplified before being converted. The focus of the application for the ADC has been these sensors as they were considered a limiting factor. The report describes theory for the algorithmic and incremental converter as well as a hybrid converter utilizing both of the two converter structures. All converters are based on one operational amplifier and they operate in repetitive fashions to obtain power efficient designs on a small chip area although at low conversion rates. Two converters have been designed and implemented to different degrees of completeness. One is a 13 bit algorithmic (or cyclic) converter which uses a switching scheme to reduce the problem of capacitor mismatch. This converter was implemented at transistor level and evaluated separately and to some extent also with sub-components. The second converter is a hybrid converter using both the operation of the algorithmic and incremental converter to obtain 16 bits of resolution while still having a fairly high sample rate.

A simple model that includes energy and carbon dioxide (CO2) emissions in the economics of machining is proposed, which has been published in the highly respected and cited journal, Annals of CIRP (International Academy for Production Engineering). This is a timely analysis in current government discussions on a proposed carbon tax or a carbon cap and trade regime and greater energy efficiency. The new cost model is based on life cycle analysis methodology for the initial part production. An illustrative example is given showing that the cheapest electrical grid should not be chosen, if it also has the highest CO2 emissions. Accurate pricing is important, because the more expensive product was highly dependent on the carbon price. A comprehensive review of machining economic models is covered. However, there is a dearth of actual machining data in the literature. This work includes studies in milling and single point incremental forming (SPIF) which can be used by other manufacturing engineers in their machining economic model development. The first milling study involved simple straight cuts. In general, as feed rate (FD) increased (increasing the material removal rate, MRR), the energy consumed decreased as process time decreased. In contrast, as spindle speed (N) increased, energy consumed increased, since more power is drawn by the motor, without a process time reduction. Given the inverse power relationship observed for the time, energy, process CO2 and cost against MRR, the recommended parameters were the same at the highest FD and lowest N permissible. In the second milling study with constant N for a more complex part (sprocket), similar relationships were observed. However, for sprockets made at constant chip load (allowing FD and N to change together), there were varying prescribed MRRs for time, energy, process CO2 and cost minimization. The SPIF studies showed a similar relationship to the constant N milling, and, that results for a simple part can be extrapolated to improve efficiency in more complex parts. Finally, although the energy and carbon costs represented a small contribution to the final cost, their significance increased for higher efficiency parameters or user conditions, e.g. low labour rate. / Thesis (Master, Mechanical and Materials Engineering) -- Queen's University, 2011-12-03 19:58:07.76

Transformations play a central role in Model Based Software Engineering. Similar to the development of other types of software, a transformation's specification and implementation does not necessarily remain static over the course of a project's lifetime; the transformation may develop incrementally and evolve. The goal of this thesis is to propose metrics that can be used to characterize the evolution of model transformations. To perform an initial demonstration of the metrics, this thesis considers an incrementally defined model transformation task. The transformation is implemented using two model transformation languages, a textual language and a graphical language, and metrics are extracted from the historical artifacts. The thesis defines a set of change metrics based on an abstract syntax difference model. Language feature metrics are also defined for both transformation languages. A process for extracting model-based change metrics and language metrics from the abstract syntax of the transformation languages is introduced. The applicability of the metrics in characterizing changes is demonstrated using exploratory clustering analysis on a transformation task. We show how, for this transformation task using both languages, metrics derived from the difference model result in clusters that reflect characteristics of individual changes, in contrast to clusters obtained with language metrics. / Thesis (Master, Computing) -- Queen's University, 2012-09-28 10:47:10.999

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Healthcare practitioners, whom perform accurate sub-maximal exercise tests in healthy individuals, need to understand the physiological demands and normal cardiovascular (CV) responses with exercise. Exercise testing delivers valid information about the physiological systems of individuals that may identify healthy individuals at risk of developing future cardiovascular disease (CVD). Exercise is a common way to assess physiological stress experienced by an individual, because CV abnormalities that are not present at rest, can be elicited during exercise testing and be used to determine the adequacy of cardiac function. Cardiovascular markers like, resting heart rate (HR) and systolic blood pressure (SBP) have been used as simple non-invasive and useful biomarkers of the fundamental status of blood circulation and the CV system in healthy individuals. Studies have contributed to exercise under sub-maximal and maximal stress testing. Modern- day literature lacks information on the safe HR and SBP responses to an increase in workload during a sub-maximal exercise protocol in healthy individuals. Consequently, the first purpose of this study was to identify the current evidence in the literature on CV response during a sub-maximal incremental exercise protocol. Different protocols and modalities contribute to various CV responses over a wide age group and gender. Heart rate and SBP increases in a linear fashion with an increase in workload, irrespective of protocol and modality. The amount of this increase, or the response of these markers, is still a grey area in the literature, especially in healthy individuals. The second purpose of this study was to analyse the HR and SBP response in healthy adults during a sub-maximal incremental exercise test, with an increase in workload (watt). The systematic review found mean changes from baseline for HR and SBP to be 75.7% and 63.5% respectively, on bicycle protocols (N = 3). The treadmill protocols (N = 2) found similar mean changes from baseline of 113.3% for HR and 36.1% for SBP. Descriptive measures as well as Linear regression analyses were performed, using Generalised estimated equations (GEE). An independent t-test was used to compare the males with the female participants: HR and SBP response to an increase in workload (watt). GEE adjustments were made for age, body mass index (BMI) and workload (watt). Significant difference levels were set at p ≤ 0.05. The present once-off subject availability results revealed that male subjects were heavier and taller than their female counterparts (p ≤ 0.05). They also had a noteworthy higher SBPrest, as well as BMI (p ≤ 0.05). The results from the GEE analyses we presented prediction equation, with all variables significant, except for the BMI (p = 0.972 females; p = 0.169 males). In conclusion, the literature review indicated a lack of information on the HR and SBP response with workload in healthy adults. It is advised that further research is needed to test the prediction equations in healthy individuals to determine the validity and reliability. They need to be tested in a controlled clinical environment, where the participants are monitored more thoroughly. By putting these predicted equations to the test, healthcare practitioners will be able to identify an exaggerated HR and SBP response with an increase in workload. If the individual’s response is exaggerated, the healthcare practitioner can intervene to prevent future cardiovascular events. / Thesis (MSc (Biokinetics))--North-West University, Potchefstroom Campus, 2013

Healthcare practitioners, whom perform accurate sub-maximal exercise tests in healthy individuals, need to understand the physiological demands and normal cardiovascular (CV) responses with exercise. Exercise testing delivers valid information about the physiological systems of individuals that may identify healthy individuals at risk of developing future cardiovascular disease (CVD). Exercise is a common way to assess physiological stress experienced by an individual, because CV abnormalities that are not present at rest, can be elicited during exercise testing and be used to determine the adequacy of cardiac function. Cardiovascular markers like, resting heart rate (HR) and systolic blood pressure (SBP) have been used as simple non-invasive and useful biomarkers of the fundamental status of blood circulation and the CV system in healthy individuals. Studies have contributed to exercise under sub-maximal and maximal stress testing. Modern- day literature lacks information on the safe HR and SBP responses to an increase in workload during a sub-maximal exercise protocol in healthy individuals. Consequently, the first purpose of this study was to identify the current evidence in the literature on CV response during a sub-maximal incremental exercise protocol. Different protocols and modalities contribute to various CV responses over a wide age group and gender. Heart rate and SBP increases in a linear fashion with an increase in workload, irrespective of protocol and modality. The amount of this increase, or the response of these markers, is still a grey area in the literature, especially in healthy individuals. The second purpose of this study was to analyse the HR and SBP response in healthy adults during a sub-maximal incremental exercise test, with an increase in workload (watt). The systematic review found mean changes from baseline for HR and SBP to be 75.7% and 63.5% respectively, on bicycle protocols (N = 3). The treadmill protocols (N = 2) found similar mean changes from baseline of 113.3% for HR and 36.1% for SBP. Descriptive measures as well as Linear regression analyses were performed, using Generalised estimated equations (GEE). An independent t-test was used to compare the males with the female participants: HR and SBP response to an increase in workload (watt). GEE adjustments were made for age, body mass index (BMI) and workload (watt). Significant difference levels were set at p ≤ 0.05. The present once-off subject availability results revealed that male subjects were heavier and taller than their female counterparts (p ≤ 0.05). They also had a noteworthy higher SBPrest, as well as BMI (p ≤ 0.05). The results from the GEE analyses we presented prediction equation, with all variables significant, except for the BMI (p = 0.972 females; p = 0.169 males). In conclusion, the literature review indicated a lack of information on the HR and SBP response with workload in healthy adults. It is advised that further research is needed to test the prediction equations in healthy individuals to determine the validity and reliability. They need to be tested in a controlled clinical environment, where the participants are monitored more thoroughly. By putting these predicted equations to the test, healthcare practitioners will be able to identify an exaggerated HR and SBP response with an increase in workload. If the individual’s response is exaggerated, the healthcare practitioner can intervene to prevent future cardiovascular events. / Thesis (MSc (Biokinetics))--North-West University, Potchefstroom Campus, 2013

This study is an investigation of the correlation between Grade 9 students’ self-theories of their intelligence and their tendency for intellectual engagement. Individuals have been shown to self-identify, with respect to their self-theories of intelligence as either entity theorists (who think of their own intelligence as fixed and fairly unchangeable), or incremental theorists (who think of their intelligence as malleable and able to be increased over time). Previous research has shown that individuals have a strong tendency to self-select one or the other of these theoretical frameworks. This study examined the correlation of this identification with individuals’ tendency to become intellectually engaged in their learning. Other demographic factors were also explored. A moderate correlation between students’ self-theory of their intelligence and their tendency for intellectual engagement was demonstrated. In this study, female students showed a higher proportion of an incremental self-theory of intelligence than males. Implications for educational leadership and classroom planning and instruction were explored

Changing artifacts is intrinsic to the development and maintenance of software projects. The changes made to one artifact, however, do not come about in isolation. Software models are often vastly entangled. As such, a minuscule modification in one ripples in- consistency through several others. The primary goal of the this thesis is to investigate techniques and processes for the synchronization of artifacts in model driven development environments in which projects comprise manifold interdependent models, each being a live document that is continuously altered and evolved. The co-evolution of these artifacts demands an efficient mechanism to keep them consistent in such dynamic environments. To achieve this consistency, we intend to explore methods and algorithms for impact anal- ysis and the propagation of modifications across heterogenous interdependent models. In particular, we consider large scale models that are generated from other models by complex artifact generators. After creation, both the generated artifacts, and also the ones they are generated from, are subject to evolutionary changes throughout which their mutual consistency should be maintained. In such situations, the model transformation is the pri- mary benchmark of consistency rules between source and target models. But the rules are often implanted inside the implementation of artifact generators and hence unavailable. Trivially, the artifacts can be synchronized by regeneration. More often than not however, regeneration of such artifacts from scratch tends to be unwieldy due to their massive size. This thesis is a summary of research on effective change management methodologies in the context of model driven development. In particular, it presents two methods of in- crementally synchronizing software models related by existing model transformations, so that the synchronization time is proportional to the magnitude of change and not to the size of models. The first approach treats model transformations as black-boxes and adds to it incremental synchronization by a technique called conceptualization. The black-box is distinguished from other undertakings in that it does not require the extraction, re- engineering and re-implementation of consistency rules embedded inside transformations. The second approach is a white-box approach that uses static analysis to automatically transform the source code of the transformation into an incremental one. In particular it uses partial evaluation to derive a specialized, incremental transformation from the exist- ing one. These two approaches are complementary and together support a comprehensive range of model transformations.

Online algorithms are characterized by operating on an input sequence revealed over time versus a single static input. Instead of generating a single solution, they produce a sequence of incremental solutions corresponding to the input seen so far. An online algorithm's ignorance of future inputs limits its ability to produce optimal solutions. The incremental nature of its solutions is also an obstacle. The two factors can be differentiated by examining the corresponding incremental algorithm, which has knowledge of future inputs, but must still provide a competitive solution at each step. In this thesis, the lower bound of the incremental constraint of k-server is shown to be to 2.

A class of migrant workers in China that have left their official rural residence in search of work and wealth in the more developed coastal cities have created a new process of urbanization. The ‘floating population’ numbering 150 million has created immense demand for low-cost housing. Village enterprises within the city region of expanding metropolises have self-organized to supply affordable housing. However, economic incentives and ownership constraints on rural land deter long-term considerations and favour rapid development. The building (and destruction) of a country cannot be recklessly left to coincidental solutions of profit opportunities in remnant policies. An understanding of the systemic political, economic and social properties that generate the built fabric of today and of traditional villages can allow us to manipulate the current process of development. The village of Zhangpeng in Dongguan city of the Pearl River Delta region is on the brink of explosive growth. Major infrastructural developments have been constructed and planned on its expropriated lands. Without proper guidance, the status quo process of urbanization will destroy the village overnight. The proposed alternative is to manipulate market-demand through village-led investment in its public space network in order to spur private development of village properties. The method is through strategic and incremental investment on village public space and property and monitoring the catalytic effect of these changes on private redevelopment. Adjustments in land development is made to steer the built fabric into a form between what the village wants it to become and what it has the propensity to be. The aim is to create a system of land development that will preserve, adapt and extend traditional village fabric and its way of life.