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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
241

Patterns of regional disparity in health outcomes in India

Agnihotri, Anustubh 20 August 2012 (has links)
India has experienced a period of unprecedented economic growth over the past few decades, credited with lifting millions out of poverty. The high rates of economic growth, however, have not led to commensurate improvements in human development indicators. While health outcomes, an important dimension of human development, have improved in India, the rate of improvement has been slow. Moreover, health outcomes vary substantially across different regions of India. The disparity in health outcomes will play a crucial role in India’s future development and necessitates new ways for targeting and evaluating policy programs. This report analyses regional disparities in health outcomes using sub-national development indicators at state, district and demographic zone level. The first chapter of the report provides an overview of health systems in India and creates a framework for understanding health disparity in India. The second chapter uses spatial mapping techniques to identify regional patterns of health disparity. The analysis uses district level indicators from health surveys and census data. The third chapter uses sub-national data to analyze infant mortality rates in India according to state and demographic zones. Along with regional variation the report also explores gender differentials and rural-urban divide in health outcomes. The final section of the report concludes by highlighting the findings, delineating a course for future research and suggesting policy measures necessary for achieving improved health outcomes. / text
242

The detection of change in spatial processes with environmental applications

Martin, Elaine B. January 1992 (has links)
Ever since Halley (1686) superimposed onto a map of land forms. the direction of trade winds and monsoons between and near the tropics and attempted to assign them a physical cause. homo-sapiens has attempted to develop procedures which quantify the level of change in a spatial process. or assess the relationship between associated spatially measured variables. Most spatial data. whether it be originally point. linear or areal in nature. can be converted by a suitable procedure into a continuous form and plotted as an isarithmic map i.e. points of equal height are joined. Once in that form it may be regarded as a statistical surface in which height varies over area in much the same way as the terrain varies on topographic maps. Particularly in environmental statistics. the underlying shape of the surface is unknown. and hence the use of non-parametric techniques is wholly appropriate. For most applications. the location of data points is beyond the control of the map-maker hence the analyst must cope with irregularly spaced data points. A variety of possible techniques for describing a surface are given in chapter two, with attention focusing on the methodology surrounding kernel density estimation. Once a surface has been produced to describe a set of data. a decision concerning the number of contours and how they should be selected has to be taken. When comparing two sets of data. it is imperative that the contours selected are chosen using the same criteria. A data based procedure is developed in chapter three which ensures comparability of the surfaces and hence spurious conclusions are not reached as a result of inconsistencies between surfaces. Contained within this chapter is a discussion of issues which relate to other aspects of how a contour should be drawn to minimise the potential for inaccuracies in the swface fitting methodology. Chapter four focuses on a whole wealth of techniques which are currently available for comparing surfaces. These range from the simplest method of overlaying two maps and visually comparing them to more involved techniques which require intensive numerical computation. It is the formalisation of the former of these techniques which forms the basis of the methodology developed in the following two chapters to discern whether change/association has materialised between variables.One means of quantifying change between two surfaces, represented as a contoured surface, is in terms of the transformation which would be required for the two surfaces to be matched. Mathematically, transformations are described in terms of rotation, translation and scalar change. Chapter five provides a geometrical interpretation of the three transformations in terms of area, perimeter, orientation and the centre of gravity of the contour of interest and their associated properties. Although grid resolution is fundamentally a secondary level of smoothing, this aspect of surface fitting has generally been ignored. However to ensure consistency across surfaces, it is necessary to decide firstly, whether data sets of different sizes should be depicted using different mesh resolutions and secondly, how fine a resolution provides optimal results, both in terms of execution time and inherent surface variability. This aspect is examined with particular reference to the geometric descriptors used to quantify change. The question of random noise contained within a measurement process has been ignored in the analysis to this point. However in practice, some form of noise will always be contained within a process. Quantifying the level of noise attributable to a process can prove difficult since the scientist may be over optimistic in his evaluation of the noise level. In developing a suitable set of test statistics, four situations were examined, firstly when no noise was present and then for three levels of noise, the upper bounds of which were 5, 15 and 25%. Based on these statistics, a series of hypothesis tests were developed to look at the question of change for individual contour levels Le. local analysis. or alternatively for a whole surface by combining the statistics and effectively performing a multivariate test. A number of problems are associated with the methodology. These difficulties are discussed and various remedial measures are proposed. The theoretical derivation of the test statistic, both in the absence and presence of random noise, has proved mathematically to be extremely complex, with a number of stringent assumptions required to enable the theoretical distribution to be derived. A major simulation study was subsequently undertaken to develop the empirical probability distribution function for the various statistics defining change for the four levels of noise. Also for each of the statistics, the resultant power of the test was examined.The remaining chapter explicitly examines two case studies and how the methodology developed in the preceding two chapters may be implemented. The first example cited raises the question, 'Has a seasonal temperature change resulted during the fifty year span, 1930 to 1980, within the contiguous United States of America?' The data base was provided by the United States Historical Climatology Network (HCN) Serial Temperature and Precipitation Data, Quinlan et al (1987). The second problem examines whether there is an association between background radiation levels, within three regions of the south-west England, and the location of various fonns of leukaemia or whether case location is a product of the population distribution. Differences between this example and the previous illustration materialise in terms of the spatial resolution of the data; the leukaemia data are defined as punctual data points and are extremely sparse; the population distribution is defined as areal regions; with the radiation data being of a more continuous format. The methodology developed required modification, but aside of this a preliminary set of conclusions were reached.
243

A Comparative examination of the use of metric information in spatial orientation and navigation

Batty, Emily Raewyn Unknown Date
No description available.
244

Redrawing Taiwanese spatial identities after martial law : text, space and hybridity in the post-colonial condition

Tseng, Ching-Pin January 2011 (has links)
Colonial powers exert dominance over their subject countries in multiple registers, for example, education and spatial constructions, which foster the colonised other‘s identification with the colonial power centre. Racial and local cultures of subject nations are thus systematically distorted and the transmission of memory through material culture is obscured. Focusing on contemporary Taiwan, this research examines how architectural and ideological strategies were employed by the dominant authorities to consolidate the power centre and explores possible means for shaping Taiwanese spatial subjectivity in the historical aftermath of such situations. The research examines the Formosans‘ ambiguous identification with local cultures and marginal spatial propositions, as well as discussing the inculcation of the 'great Chinese ideology‘ by analysing the teaching materials used in modern Taiwanese primary education. Reviewing aspects of contemporary post-colonial theory, the research explores the spatial implications of Taiwanese post-colonial textual narratives and argues for them as a potential source for the construction of contemporary spatial conditions, as these novels are shaped by an awareness of the importance of local cultures and the voices of marginalised people. The thesis thus suggests that a re-thinking of Taiwan‘s public spaces can be stimulated by spatial metaphors in textual narratives that associate peoples‘ memories of political and local events with spatial images that were previously suppressed. To explore the potential for the generation of space through reference to literary works, this research studies the ‗narrative architecture‘ experiments of the 1970s and 80s and goes on to propose a series of representational media for the construction of spatial narrations in Taiwan. Multiple spatial propositions concerning the island‘s post-colonial condition can be suggested by the visualisation of spatial metaphors that are embedded in Taiwanese textual narratives. At the end of the thesis, two proposals for post-colonial spatial narration are put forward, which transform the spatial propositions latent in the devices developed through a new juxtaposition with existing urban contexts. The intention of the research is to indicate a new urban spatial strategy for Taiwan, one that can allow its people to grasp the multiple layers of their conflicted spatial history while at the same time responding to the ongoing spatial confrontation between the power centre and the voices in the margins.
245

Lateral Biases in Attention and Working Memory Systems

2014 April 1900 (has links)
Neurologically healthy individuals misbisect their visual space by erring towards the left. This misreprentation has been attributed to the right hemisphere dominance in processing of spatial information. Lateral biases are thought to emerge as behavioural outcomes of cognitive processing, mainly attention. Recently, attention mechanisms have been reported to be closely inter-related to memory systems, where attention directs what will be remembered and memory impacts where attention is directed. Although spatial biases attributed to attention have been widely accepted, the claim that memory exhibits similar biases has been more controversial. Recent research shows that recall of representations is biased towards the left side of space, indicating that lateral asymmetries may not necessarily be limited to perceptual and attentional mechanisms, but may extend to memory mechanisms as well. The purpose of this work is to understand better the relationship between lateral biases within working memory and attention interactions. Two approaches were considered. First, working memory, as defined by the representations and operations related to manipulate the representations, used time delay and visual load. Second, backward masking was used to control the relative formation of the working memory trace, which strengthens with recurrence of the visual stimuli and is through to progress from attention to working memory. To explore these two theoretical avenues, a novel task was constructed. Two circular arrays were presented at the top and bottom of the computer screen. These arrays were composed of six individual discs of varying shade. Hence, the overall array represented a greyscale gradient, where discs on one lateral side were darker compared to the middle discs and the other lateral side. For example, if two darkest discs were presented on the left side, the lightest discs were presented on the right side. Such array was presented with its left/right mirror reversed image. In this example, the second array was with the lightest discs on the left side and growing progressively darker, with darkest discs on the right side. Such presentation requires the participants to integrate the array of individual discs into an overall representation to perform a brightness judgement and select the array seemingly darker. A total of six behavioural studies addressed the two theoretical approaches. The first approach, to determine the impact of inter-stimulus time interval and visual load on lateral asymmetries, was addressed in four experiments. The findings indicated that participants were able to integrate the discrete disks into an overall array. Participants exhibited an overall leftward bias similar to that obtained in attention tasks, where they selected an array to be overall darker when the darkest disks were presented on the left side of the array. Furthermore, these biases increased the most when the stimuli were presented in the lower half of the computer screen, consistent with the lower visual field. Conversely, stimuli presented to the upper half of the screen elicited a rightward bias, which is consistent with the upper visual field. Stronger biases were observed when the stimulus noise, in the form of black, white and grey pixels, was relatively low and weaker biases were attained with a relatively high noise levels. In the second study, the findings showed that the magnitude of upper and lower visual field biases shows dependence on the vertical and lateral stimulus manipulation within these fields. Upper-left, lower-right interactions indicate that biases may not simply rely on the horizontal and vertical dimensions, as previously thought, but also on the relative spatial distribution of stimuli within these dimensions. The third study, which used the standard rectangular greyscale stimuli, revealed that visual load does not impact the lateral biases, but shows to impact the upper and lower visual field processing. Further, time interval between stimulus presentation and response, extended past 1 second eliminated lateral and vertical biases. The remaining two studies investigated lateral asymmetries within working memory by selectively manipulating the formation of working memory trace using backward masks. The presence of a mask, following a stimulus, inhibits the memory trace formation for that stimulus. Conversely, if no mask is presented following the stimuli, the memory trace is permitted to form within working memory. Again, using the circular array task, participants were required to select the overall darker array while retaining either a shade of position information from the array within their working memory. Findings showed increased rightward biases when memory trace was permitted to form with longer inter-stimulus (3 sec) time interval, as compared to shorter (0 to 1 sec) time interval. In the last study, the participants were required to make brightness judgement while maintaining either a position or shade information within working memory to determine whether previously acquired information, which does not serve as a cue, impact the brightness judgement task. Rightward biases were evident when participants were required to maintain either a position or shade information relating to the array, but did not provide any cue-type of information, which could facilitate performance. Rightward biases were stronger while retaining position information and completing the brightness task, hence indicating a spatial nature of the bias. As well, stronger rightward biases were obtained when the to-be-remembered position information was allowed to create a memory trace. Furthermore, recall accuracy of the position information was increased when the memory trace was permitted to form, indicating involvement of working memory processes. Overall, the data attained in this set of experiments can be interpreted using the activation-orientation model presented by Reuter-Lorenz (1990) indicating that this model may also be valuable when integrating working memory in addition to attentional processes.
246

Exploring the Feasibility of Achieving Energy Self-sufficiency ??? A Residential Electricity Case Study in Ontario

Li, Hang January 2013 (has links)
As energy security and climate issues are emerging as global concerns, it is commonly agreed that a transition from a conventional centralized energy system, which is largely based on combustion of fossil fuel, to a more sustainable decentralized energy system that includes mainly renewable energy sources is necessary and urgent. Due to the highly variable geographical qualities of renewable energy sources, spatial energy planning is becoming essential. This study aims to address the challenges in linking spatial modelling with assessment of regional energy consumption and renewable energy supply potential. A novel approach for exploring the feasibility of achieving energy self-sufficiency through matching energy deficit areas with energy surplus areas is proposed. A method for energy deficit and surplus area matching is developed and implemented in a VBA- based tool that serves as a decision-support tool by exploring possible future deployment of renewable energy in decentralized ways. Achieving Ontario residential electricity self-sufficiency through solar PV energy on an annual basis is explored as a case study. The results show that it is technically feasible for Ontario to be residential electricity self-sufficient through the development of solar PV energy with energy deficit areas within the region getting energy supply from nearby energy surplus areas. The case study implies that regional residential electricity self- sufficiency is achievable and it is useful for planners and policy makers to bear the regional energy deficit-surplus matching idea in mind when making urban and energy plans.
247

Individual differences and strategies for human reasoning

Bacon, Alison Margaret January 2003 (has links)
Theories of human reasoning have tended to assume cognitive universality, i.e. that all individuals reason in basically the same way. However, some research (e.g. that of Ford. 1995) has found evidence of individual differences in the strategies people use for syllogistic reasoning. This thesis presents a series of experiments which aimed to identify individual differences in strategies for human reasoning and investigate their nature and aetiology. Experiment 1 successfully replicated and extended Ford (1995) and provided further evidence that most individuals prefer to reason with either verbal-propositional or visuo-spatial representations. Data from verbal and written protocols showed that verbal reasoners tended to use a method of substitution whereby they obtain a value for the common term from one premise and then simply substitute it in the other premise to obtain a conclusion. Spatial reasoners, on the other hand, presented protocols which resembled Euler circles and described the syllogistic premises in terms of sets and subsets. Experiment 2 provided some further qualitative evidence about the nature of such strategies, especially the verbal reasoners, showing that within strategy variations occurred. Experiment 3 extended this line of research, identifying a strong association between verbal and spatial strategies for syllogistic reasoning and abstract and concrete strategies for transitive inference (the latter having originally been identified by Egan and Grimes- Farrow, 1982). Experiments 1-3 also showed that inter-strategic differences in accuracy are generally not observed, hence, reasoners present an outward appearance of ubiquity despite underlying differences in reasoning processes. Experiments 5 and 6 investigated individual differences in cognitive factors which may underpin strategy preference. Whilst no apparent effects of verbal and spatial ability or cognitive style were found, reasoners did appear to draw differentially on the verbal and spatial components of working memory. Confirmatory factor analysis showed that whilst verbal reasoners draw primarily on the verbal memory resource, spatial reasoners draw both on this and on spatial resource. Overall, these findings have important implications for theories of human reasoning, which need to take into account possible individual differences in strategies if they are to present a truly comprehensive account of how people reason.
248

Reinforcement learning of visually guided spatial goal directed movement

Toombs, Paul January 1997 (has links)
A range of visually guided, spatial goal directed tasks are investigated, using a computational neuroethology approach. Animats are embedded within a bounded, 2-D environment, and map a 1-D visual array, through a convolution network, to a topography preserving motor array that stochastically determines the direction of movement. Temporal difference reinforcement learning modifies the convolution network in response to a reinforcement signal received only at the goal location. Three forms of visual coding are compared: multiscale coding, where the visual array is convolved by Laplacian of Gaussian filters at a range of spatial scales before convolution to determine the motor array; rectified multiscale coding, where the multiscale array is split into positive and negative components; and intensity coding, where the unfiltered visual array is convolved to determine the motor array. After learning, animats are examined in terms of performance, behaviour and internal structure. When animats learn to approach a solitary circle, of randomly varying contrast, rectified multiscale coding animats learn to outperform multiscale and intensity coding animats in both independent and coarse scale noise conditions. Analysis of the learned internal structure shows that rectified multiscale filtering facilitates learning by enabling detection of the circle at scales least affected by noise. Cartwright and Collett (1983) showed that honeybees learn the angle subtended by a featureless landmark to guide movement to a food source at a fixed distance from the landmark, and furthermore, when tested with only the edges of the landmark, still search in the same location. In a simulation of this experiment, animats are reinforced for moving to where the angle subtended by a solitary circle falls within a certain range. Rectified multiscale filtering leads to better performing animats, with fewer hidden units, in both independent and coarse scale visual noise conditions, though for different reasons in each case. Only those animats with rectified multiscale filtering, that learn in the presence of coarse scale noise, show similar generalisation to the honeybees. Collett, Cartwright and Smith (1986) trained gerbils to search at locations relative to arrangemments of landmarks and tested their search patterns in modifications of the training arrangements. These experiments are simulated with landmark distance coded as either a 1-D intensity array, or a 2-D vector array, plus a simple compass sense. Vector coding animats significantly outperform those using intensity coding and do so with fewer hidden units. Furthermore, vector coding animats show a close match to gerbil behaviour in tests with modified landmark arrangements.
249

Optimal Siting of Distributed Wind Farms in Ontario, Canada

Binnington, Taylor 18 March 2013 (has links)
Increasing wind penetration adds to the importance of enhancing the reliability of wind, to mitigate the magnitude and frequency of changes in electricity generation. This work addresses how improvements can be made to reliability through the geographic dispersal of wind farms in Ontario, Canada, using modeled North American Regional Reanalysis data. Optimal configurations of wind farm locations are determined according to two criteria. The first selects combinations of wind farms that follow temporal demand patterns, by maximizing the difference between the energy price and the cost of electricity. The second attempts to select combinations of wind farms that minimize the coefficient of variation in the aggregate output. It is found that there are no wind regimes in Ontario that match demand sufficiently for a viable development strategy, but that combinations of as few as three locations can reduce the coefficient of variation by over 30%, compared to a single region.
250

Optimal Siting of Distributed Wind Farms in Ontario, Canada

Binnington, Taylor 18 March 2013 (has links)
Increasing wind penetration adds to the importance of enhancing the reliability of wind, to mitigate the magnitude and frequency of changes in electricity generation. This work addresses how improvements can be made to reliability through the geographic dispersal of wind farms in Ontario, Canada, using modeled North American Regional Reanalysis data. Optimal configurations of wind farm locations are determined according to two criteria. The first selects combinations of wind farms that follow temporal demand patterns, by maximizing the difference between the energy price and the cost of electricity. The second attempts to select combinations of wind farms that minimize the coefficient of variation in the aggregate output. It is found that there are no wind regimes in Ontario that match demand sufficiently for a viable development strategy, but that combinations of as few as three locations can reduce the coefficient of variation by over 30%, compared to a single region.

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