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A feminist analysis of the 1996 South African population census with specific focus on the questions pertaining to the household : implications for development policy and practice.Khan, Zohra. January 2001 (has links)
This study analyses the 1996 South African population census from a feminist
perspective by focusing on the questions pertaining to the household. It considers the
issue of gender power relations operating at the level of the household and challenges the
underlying patriarchal ideology embedded in the census itself. The study into households
is situated within the context of current development discourse and practice, and is
premised on the role of the census as a key national resource providing information on all
sectors of society. Individual structured interviews were carried out with members of the
census task team who provided valuable insight into the process of census making.
Interviews with academics and activists working on gender issues were also conducted. A
semi-structured focus group discussion was conducted with five women living in the
Molweni district in KwaZulu-Natal in August 1998 to gather information on productive,
reproductive and community managing work and activities. The study makes an
argument about the importance of including unpaid reproductive work in our national
statistics. The census questionnaire is analysed and a few adjustments are recommended
that may allow for the inclusion of unpaid, reproductive labour in the national statistical
system. / Thesis (M.A.)-University of Natal, Durban, 2001.
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Investigation into the Origin and Nature of Variability in Quantitative Measurements of Tumour Blood Flow with Contrast-enhanced UltrasoundSureshkumar, Ahthavan R. 27 November 2012 (has links)
Microbubble ultrasound (US) contrast agents have been used to monitor the progression of anti-angiogenic chemotherapies. However, US backscatter measurements used in contrast imaging are inherently variable, given the presence of many microbubbles of random position and size. A model was developed to investigate the influence of US scanner and microbubble characteristics on these variable measurements. The Coefficient of Variation was used to measure variability. It was found that an optimum excitation frequency exists that minimizes this variability. In the case of DefinityTM, a 2.25 MHz centre-frequency pulse yielded a less variable measurement than at 5 MHz. Conversely, decreasing microbubbble concentration was found to significantly increase variability. Evidence suggests that microbubbles are no longer Rayleigh scatterers at sufficient low concentrations. Post-processing was found to aid in reducing measurement variability by averaging samples where microbubble positions are uncorrelated. As well, reduction can be achieved by averaging about a region-of-interest of uniform perfusion.
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Visualising attribute and spatial uncertainty in choropleth maps using hierachical spatial data modelsKardos, Julian, n/a January 2006 (has links)
This thesis defines a novel and intuitive method to visually represent attribute uncertainty, and spatial boundary uncertainty generated from choropleth maps. Like all data, it is not possible to know exactly how far from the truth spatial data used for choropleth mapping is. When spatial data is used in a decision-making context a visual representation of data correctness may become a valuable addition. As an example, the visualisation of uncertainty is illustrated using choropleth mapping techniques superimposed on New Zealand 2001 census data, but other spatial datasets could have been employed. Both attribute and spatial uncertainty are considered, with Monte Carlo statistical simulations being used to model attribute uncertainty.
A visualisation technique to manage certain choropleth spatial boundary issues (i.e. the modifiable areal unit problem - MAUP) and uncertainty in attribute data is introduced, especially catering for attribute and choropleth spatial boundary uncertainty simultaneously. The new uncertainty visualisation method uses the quadtree spatial data model (SDM) in a novel manner. It is shown that by adapting the quadtree SDM to divide according to uncertainty levels possessed by attributes (associated with areal units), rather than divide on the basis of homogeneous regions (as the original quadtree design was intended), a measure of attribute and choropleth spatial boundary uncertainty can be exhibited. The variable cell size of the structure expresses uncertainty, with larger cell size indicating large uncertainty, and vice versa. The new quadtree SDM was termed the trustree. A software suite called TRUST v1.0 (The Representation of Uncertainty using Scale-unspecific Tessellations) was developed to create square trustree visualisations.
The visual appeal and representational accuracy of the trustree was investigated. Representative accuracy and visual appeal increased when using hexagonal tessellations instead of the quadtree�s traditional square tessellation. In particular, the Hexagonal or Rhombus (HoR) quadtree designed by Bell et al. (1989) was used to programme TRUST v1.1. Using the HoR quadtree in rhombic mode (TRUST v1.1.1) produced Orbison�s optical illusion, so it was disregarded. However, the HoR trustree (the hexagonal tessellation produced by TRUST v1.1.2) was adopted for further research and user assessment. When assessed using an Internet survey, the HoR trustree adequately displayed choropleth spatial boundary uncertainty, but not attribute uncertainty. New trustree visualisations, the value-by-area (VBA) trustree and adjacent HoR trustree were developed to help increase the expression of attribute uncertainty. Upon reassessment, the new trustree visualisations were deemed usable to express attribute uncertainty and choropleth spatial boundary uncertainty at a modest 58% usable (HoR trustree), 80% usable (VBA trustree) and 85% usable (adjacent HoR trustree). A usability test (where participants were asked to spot different levels of uncertainty) validated these results, whereby the HoR trustree achieved a 65% accuracy level and the VBA trustree achieved an 80% accuracy level. The user assessments helped to highlight that the trustree could be used in two ways, to express detail within or clutter over areal units. The HoR trustree showed (1) a level of detail (or resolution) metaphor, where more detail represented more accuracy and/or the reverse, (2) a metaphor of clutter, where the data structure output was sufficiently dense as to cover spatial information, in effect hiding uncertain areas. Further Internet survey testing showed the trustree tessellation works better when representing a metaphor of detail. Attribute and spatial uncertainty can be effectively expressed depending on the tessellation level used.
Overall, the new TRUST suite visualisations compare favourably with existing uncertainty visualisation techniques. Some uncertainty visualisation methods consistently performed better than the TRUST visualisations such as blinking areas, adjacent value and non-continuous cartograms. Other methods like colour saturation, image sharpness and a three-dimensional surface frequently performed with less usability. Therefore, the TRUST visualisations have found their place amongst other uncertainty visualisation methods. However, survey results showed that TRUST is a viable option for visualising two forms of uncertainty - attribute and spatial uncertainty. No other visualisation method has these capabilities. Further research could include a laboratory assessment of TRUST and also incorporating vagueness and temporal uncertainty concepts. Additionally, end-user testing could provide a valuable insight into uncertainty visualisation for everyday use. Adopting uncertainty methods to uncertainty, such as the technique presented here, into the mainstream decision making environment could be considered a fundamental objective for future investigation in spatial studies.
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Simulation of suicide tendency by using machine learningCalderon-Vilca, Hugo D., Wun-Rafael, William I., Miranda-Loarte, Roberto 07 1900 (has links)
El texto completo de este trabajo no está disponible en el Repositorio Académico UPC por restricciones de la casa editorial donde ha sido publicado. / Suicide is one of the most distinguished causes of death on the news worldwide. There are several factors and variables that can lead a person to commit this act, for example, stress, self-esteem, depression, among others. The causes and profiles of suicide cases are not revealed in detail by the competent institutions. We propose a simulation with a systematically generated dataset; such data reflect the adolescent population with suicidal tendency in Peru. We will evaluate three algorithms of supervised machine learning as a result of the algorithm C4.5 which is based on the trees to classify in a better way the suicidal tendency of adolescents. We finally propose a desktop tool that determines the suicidal tendency level of the adolescent. / Revisión por pares
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Analyse régionale des causes démographiques du vieillissement de la population portugaiseNazaret, J. Manuel January 1978 (has links)
Doctorat en sciences sociales, politiques et économiques / info:eu-repo/semantics/nonPublished
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The Physics of Mergers: Theoretical and Statistical Techniques Applied to Stellar Mergers in Dense Star ClustersLeigh, William Nathan 10 1900 (has links)
<p>In this thesis, we present theoretical and statistical techniques broadly related to systems of dynamically-interacting particles. We apply these techniques to observations of dense star clusters in order to study gravitational interactions between stars. These include both long- and short-range interactions, as well as encounters leading to direct collisions and mergers. The latter have long been suspected to be an important formation channel for several curious types of stars whose origins are unknown. The former drive the structural evolution of star clusters and, by leading to their eventual dissolution and the subsequent dispersal of their stars throughout the Milky Way Galaxy, have played an important role in shaping its history. Within the last few decades, theoretical work has painted a comprehensive picture for the evolution of star clusters. And yet, we are still lacking direct observational confirmation that many of the processes thought to be driving this evolution are actually occuring. The results presented in this thesis have connected several of these processes to real observations of star clusters, in many cases for the first time. This has allowed us to directly link the observed properties of several stellar populations to the physical processes responsible for their origins.</p> <p>We present a new method of quantifying the frequency of encounters involving single, binary and triple stars using an adaptation of the classical mean free path approximation. With this technique, we have shown that dynamical encounters involving triple stars occur commonly in star clusters, and that they are likely to be an important dynamical channel for stellar mergers to occur. This is a new result that has important implications for the origins of several peculiar types of stars (and binary stars), in particular blue stragglers. We further present several new statistical techniques that are broadly applicable to systems of dynamically-interacting particles composed of several different types of populations. These are applied to observations of star clusters in order to obtain quantitative constraints for the degree to which dynamical interactions affect the relative sizes and spatial distributions of their different stellar populations. To this end, we perform an extensive analysis of a large sample of colour-magnitude diagrams taken from the ACS Survey for Globular Clusters. The results of this analysis can be summarized as follows: (1) We have compiled a homogeneous catalogue of stellar populations, including main-sequence, main-sequence turn-off, red giant branch, horizontal branch and blue straggler stars. (2) With this catalogue, we have quantified the effects of the cluster dynamics in determining the relative sizes and spatial distributions of these stellar populations. (3) These results are particularly interesting for blue stragglers since they provide compelling evidence that they are descended from binary stars. (4) Our analysis of the main-sequence populations is consistent with a remarkably universal initial stellar mass function in old massive star clusters in the Milky Way. This is a new result with important implications for our understanding of star formation in the early Universe and, more generally, the history of our Galaxy. Finally, we describe how the techniques presented in this thesis are ideally suited for application to a number of other outstanding puzzles of modern astrophysics, including chemical reactions in the interstellar medium and mergers between galaxies in galaxy clusters and groups.</p> / Doctor of Philosophy (PhD)
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國際速食業在台競爭態勢之檢視視及其市場區隔分析-AID之應用研究陳玉君, CHEM, YU-JUN Unknown Date (has links)
本論文共分七章,探討速食業者在消費者心目中之優劣地位,並以一般生活型態變數
、特殊生活型態變數、以及人口統計變量為基準,應用AID 方法將市場分隔,希望據
此描述市場特質以供業者作策略的參考。
第一章:緒論,共分三節,包括研究動機、目的、研究對象、範圍、研究架構及概述
。
第二章:台灣速食產業概況介紹,共分三節,包括餐飲業之產業結構介紹、國內速食
產業之現況。
第三章:理論基礎及文獻探討,共分四節。
第四章:研究方法,共分九節,包括研究流程、假設、工具、限制、操作性定義、抽
樣與樣本結構,以及資料分析步驟和方法。
第五章:當前台灣速食業者競爭態勢分析,共分三節,包括中、西式速食業者在消費
者之各評估屬性的優劣比較、業者整體態勢之分析,以及消費者產品相關行為之差異
分析。
第六章:速食業之市場區隔分析-AID 之應用,共分三節,包括一般生活型態因素之
萃取、速食市場之區隔及描述。
第七章:結論及建議,共分三節,包括研究結論、政策涵義以及後續研究。
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OPTICAL PROPERTIES AND POPULATION STATISTICS OF ERBIUM IN OPTICALLY-PUMPED ERBIUM-DOPED ZINC SILICATE GERMANATE WAVEGUIDE AMPLIFIERSBANERJEE, SIDDHARTHA January 2004 (has links)
No description available.
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Demographic change and economic development at the local level in BrazilAmaral, Ernesto F. L. (Ernesto Friedrich de Lima), 1977- 28 August 2008 (has links)
In this analysis, I estimate the impact of the changing relative size of the adult male population, classified by age and education groups, on the earnings of employed males living in 502 Brazilian local labor markets during four time periods between 1970 and 2000. The effects of shifts in the age distribution of the working age population have been studied in relation to the effect of the baby-boom generation on the earnings of different cohorts in the United States. However, the question has received little attention in the context of the countries in Asia and Latin America, which are now experiencing substantial shifts in their age-education distributions. Taking advantage of the huge variation across Brazilian local labor markets, the models in this research suggest that age-education groups are not perfect substitutes, so that own-cohort-education size depresses earnings, as expected by the theory. Compositional shifts are influential, attesting that this approach represents a fruitful way of studying this central problem in economic development, going beyond the effects normally analyzed by formal labor market equations. / text
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The socio-spatial boundaries of an 'invisible' minority : a quantitative (re)appraisal of Britain's Jewish populationGraham, David J. January 2009 (has links)
This study, located in the disciplines of human geography and demography, explores the socio-spatial boundaries encapsulating Britain’s Jewish population, particularly at micro-scales. It highlights and challenges key narratives of both Jewish and general interest relating to residential segregation, assimilation, partnership formation, exogamy and household living arrangements. It presents a critical exploration of the dual ethnic and religious components of Jewish identity, arguing that this ‘White’ group has become ethnically ‘invisible’ in British identity politics and, as a consequence, is largely overlooked. In addition, the key socio-demographic processes relating to Jewish partnership formation are addressed and a critical assessment of data pertaining to the decline of marriage, the rise of cohabitation and the vexed topic of Jewish exogamy, is presented. The analysis culminates by linking each of these issues to the micro-geographical scale of the household and develops a critical assessment of this key unit of Jewish (re)production. Jewish population change is contextualised within the framework of the second demographic transition. This deliberately quantitative study is designed to exploit a recent glut of data relating to Jews in Britain. It interrogates specially commissioned tables from Britain’s 2001 Census as well as four separate communal survey data sources. It highlights and challenges recent geographical critiques of quantitative methodologies by presenting a rigorous defence of quantification in post-‘cultural turn’ human geography. It emphasises the importance and relevance of this fruitful shift in geographical thought to quantitative methods and describes the role quantification can now play in the discipline. Above all, it synthesises two disparate sets of literature: one relating to geographical work on identity and segregation, and the other to work on the identity, demography and cultural practices of Jews. As a result, this thesis inserts the largely neglected ethno-religious Jewish case into the broader geographical literature whilst developing a critical quantitative spatial agenda for the study of Jews.
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