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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.
341

The (mis)use of adult age estimates in osteology.

Buckberry, Jo January 2015 (has links)
Yes / Context: Adult age-at-death is presented in a number of different ways by anthropologists. Ordinal categories predominate in osteoarchaeology, but do not reflect individual variation in ageing, with too many adults being classified as ‘middle adults’. In addition, mean ages (derived from reference samples) are overly-relied upon when developing and testing methods. In both cases, ‘age mimicry’ is not adequately accounted for. Objectives: To highlight the many inherent biases created when developing, testing and applying age-estimation methods without fully considering the impact of ‘age mimicry’ and individual variation. Methods: The paper draws on previously published research (Web of Science, Pub Med, Google Scholar) on age estimation methods and their use in anthropology. Results and Conclusions: There is a lack of consistency in the methods used to estimate age, and for the mode of combining them. Ordinal categories are frequently used in osteoarchaeology, whereas forensic anthropologists are more likely to produce case-specific age ranges. Mean ages reflect the age structure of reference samples, and should not be used to estimate age for individuals from populations with a different age-at-death structure. Individual-specific age ranges and/or probability densities should be used to report individual age. Further research should be undertaken on how to create unbiased, combined method age estimates.
342

Invariants numériques de catégories de fusion : calculs et applications / Numerical invariants of fusion categories : calculations and applications

Mignard, Michaël 14 December 2017 (has links)
Les catégories de fusion pointées sont des catégories de fusion pour lesquelles les objets simples sont inversibles. Nous développons des méthodes basés par ordinateur pour classifier les catégories pointées à équivalence de Morita près, et les appliquons aux catégories pointées de dimensions comprises entre 2 et 32. Nous prouvons qu'il existe 1126 classes de Morita pour de telles catégories. Aussi, nous prouvons que les indicateurs de Frobenius-Schur du centre d'une catégorie pointée de dimension inférieure à 32, accompagnés de structure enrubannée de ce centre, déterminent sa classe de Morita. Ceci est faux en général: les données modulaires, et donc a fortiori les indicateurs et structures enrubannées, ne distinguent pas les catégories modulaires. Nous donnons une famille d'exemples ; en réalité, il existe un nombre arbitrairement grand de catégories modulaires deux-à-deux non équivalentes qui peuvent partager les mêmes données modulaires. / Pointed fusion categories are fusion categories in which all simple objects are invertible. We develop computer-based methods to classify pointed categories up to Morita equivalence, and apply them to pointed fusion categories of dimension from 2 to 31. We prove that there are 1126 Morita classes of such categories. Also, we prove that the Frobenius-Schur indicators of the centers of a pointed category of dimension less than 32, along with its ribbon twist, determine its Morita class. This is not true in general: the modular data, and a fortiori the indicators and the ribbon twists, do not distinguish modular categories. We give a family of examples; in fact, arbitrarly many pairwise non-equivalent modular categories can share the same modular data.
343

Image classification for a large number of object categories

Bosch Rué, Anna 25 September 2007 (has links)
L'increment de bases de dades que cada vegada contenen imatges més difícils i amb un nombre més elevat de categories, està forçant el desenvolupament de tècniques de representació d'imatges que siguin discriminatives quan es vol treballar amb múltiples classes i d'algorismes que siguin eficients en l'aprenentatge i classificació. Aquesta tesi explora el problema de classificar les imatges segons l'objecte que contenen quan es disposa d'un gran nombre de categories. Primerament s'investiga com un sistema híbrid format per un model generatiu i un model discriminatiu pot beneficiar la tasca de classificació d'imatges on el nivell d'anotació humà sigui mínim. Per aquesta tasca introduïm un nou vocabulari utilitzant una representació densa de descriptors color-SIFT, i desprès s'investiga com els diferents paràmetres afecten la classificació final. Tot seguit es proposa un mètode par tal d'incorporar informació espacial amb el sistema híbrid, mostrant que la informació de context es de gran ajuda per la classificació d'imatges. Desprès introduïm un nou descriptor de forma que representa la imatge segons la seva forma local i la seva forma espacial, tot junt amb un kernel que incorpora aquesta informació espacial en forma piramidal. La forma es representada per un vector compacte obtenint un descriptor molt adequat per ésser utilitzat amb algorismes d'aprenentatge amb kernels. Els experiments realitzats postren que aquesta informació de forma te uns resultats semblants (i a vegades millors) als descriptors basats en aparença. També s'investiga com diferents característiques es poden combinar per ésser utilitzades en la classificació d'imatges i es mostra com el descriptor de forma proposat juntament amb un descriptor d'aparença millora substancialment la classificació. Finalment es descriu un algoritme que detecta les regions d'interès automàticament durant l'entrenament i la classificació. Això proporciona un mètode per inhibir el fons de la imatge i afegeix invariança a la posició dels objectes dins les imatges. S'ensenya que la forma i l'aparença sobre aquesta regió d'interès i utilitzant els classificadors random forests millora la classificació i el temps computacional. Es comparen els postres resultats amb resultats de la literatura utilitzant les mateixes bases de dades que els autors Aixa com els mateixos protocols d'aprenentatge i classificació. Es veu com totes les innovacions introduïdes incrementen la classificació final de les imatges. / The release of challenging data sets with ever increasing numbers of object categories isforcing the development of image representations that can cope with multiple classes andof algorithms that are efficient in training and testing. This thesis explores the problem ofclassifying images by the object they contain in the case of a large number of categories. We first investigate weather the hybrid combination of a latent generative model with a discriminative classifier is beneficial for the task of weakly supervised image classification.We introduce a novel vocabulary using dense color SIFT descriptors, and then investigate classification performances by optimizing different parameters. A new way to incorporate spatial information within the hybrid system is also proposed showing that contextual information provides a strong support for image classification. We then introduce a new shape descriptor that represents local image shape and its spatial layout, together with a spatial pyramid kernel. Shape is represented as a compactvector descriptor suitable for use in standard learning algorithms with kernels. Experimentalresults show that shape information has similar classification performances and sometimes outperforms those methods using only appearance information. We also investigate how different cues of image information can be used together. Wewill see that shape and appearance kernels may be combined and that additional informationcues increase classification performance. Finally we provide an algorithm to automatically select the regions of interest in training. This provides a method of inhibiting background clutter and adding invariance to the object instance's position. We show that shape and appearance representation over the regions of interest together with a random forest classifier which automatically selects the best cues increases on performance and speed. We compare our classification performance to that of previous methods using the authors'own datasets and testing protocols. We will see that the set of innovations introduced here lead for an impressive increase on performance.
344

Svenska studenters uppfattningar av tonerna i kinesiska tvåstaviga ord

Hu, Guohua January 2015 (has links)
Studenter med ett icke-tonspråk som modersmål brukar ha svårigheter att lära sig de kinesiskatonerna när de börjar sina studier. Å ena sidan brukar kursböckerna på denna nivån användabara enstaviga ord och det har ansetts vara god pedagogik att läraren visar tonkonturerna medsina händer. Å andra sidan har forskningen om kinesiska länge varit koncentrerad på vilkavärden som grundtonen (F0) uppvisar i enstaviga ord. Det är många faktorer som tvärspråksforskningeninte har uppmärksammat, bl.a. det inflytande som konsonanterna har på F0 (vilketinfödda talare inte alltid är medvetna om).Det finns ingen samsyn när det gäller att förklara tonförväxlingsmönstren. Tidigare teorierinom ämnet andraspråksinlärning (Second Language Acquisition, SLA), som Perception AssimilationModel (PAM) och Speech Learning Model (SLM) har visat sig otillräckliga förstudiet av tonperception. På senare tid har PAM-Suprasegment försökt förklara hur den lärandesmodersmål antas närma sig kinesiskans tonsystem men modellen tar inte upp ordprosodin.Eftersom den moderna kinesiskans ordförråd till majoriteten består av tvåstaviga ord börforskningen lämna gamla spår för att finna andra kriterier – som duration och betoning – föratt förklara hur man lär sig höra kinesiskans toner, t.ex. vad som händer när två toner återfinnsi ett ord.Denna studie har som mål att ta reda på hur svenskar som studerar kinesiska som andraspråk/främmande språk uppfattar tonerna i kinesiska tvåstaviga ord. Experimentet bygger intepå tillrättalagda testord. Resultaten visar att tonerna först och främst påverkas av den initialakonsonanten och sedan av de omgivande tonerna. Vidare visas att det svenska systemet medaccent I och II i sin tur kan åstadkomma tonförväxlingar eftersom kinesiska tvåstaviga orddelvis uppvisar samma mönster.Resultaten illustrerar att tonidentifiering är en dynamisk och komplex process. Det krävsfortsatt forskning om tonerna för att få grepp om dem men det kan inte stanna där: interaktionenmellan ljud och ordprosodi behöver belysas bättre för att uppnå god behärskning avprosodin i språkundervisningen. / Foreign adult students with atonal language usually have, in the beginning of their Chinesestudy, difficulties to identify the Chinese tones. On one side, only monosyllabic tones arementioned in course books during this earlier stage and to illustrate the tone contours withhands has been treated as an effective pedagogy. On the other side, research on Chinese hasfor long been solely concentrated upon the values of the fundamental frequency (F0) of thevowels in monosyllabic words. In cross-linguistic studies many factors, among others the effectsof consonants on F0 that native speakers are not aware of, have still not been paidspecial attention to.There is no consensus regarding the explanation to tone confusion patterns. Earlier theoriesof Second Language Acquisition (SLA) like Perception Assimilation Model (PAM) andSpeech Learning Model (SLM) are no longer suited for tone perception. Recently, PAMSuprasegmenthas tried to approach that the intonation of the learners’ native language is assumedto be assimilated to the Chinese tone system. However, this model ignores the wordprosody. Nowadays, when the modern Chinese vocabulary consists of a majority of disyllabicwords, research has to be re-directed to find other criteria e.g. temporal and stress for explainingthe complexity of Chinese tone perception, i.e. how two tones behave when they arecombined in one word.The purpose of this essay is to explore how native Swedish speakers learning Chinese assecond/foreign language perceive the Chinese tones of disyllabic words. The experiment isnot based on elaborated test words. The results show that tones are first of all affected by theinitial consonants and sequentially influenced by the surrounding tones with accordance toChinese. It further reveals that Swedish accent I/II patterns might be a reasonable explanationfor the Chinese tone confusion patterns since partially acoustic properties of Chinese disyllabicwords overlap the Swedish accents.These results mean that tone perception is a dynamic and complex process. Further researchon tone perception should explore profoundly and widen interaction between sounds andword prosody, which paves the way for more effective prosodic practice in language education.
345

Ecological factors associated with speciation in New Zealand triplefin fishes (Family Tripterygiidae)

Wellenreuther, Maren January 2007 (has links)
Theoretical research has demonstrated that ecological interactions in sympatry or parapatry can generate disruptive selection that in concert with assortative mating can lead to speciation. However, empirical examples are few and restricted to terrestrial and lacustrine systems. New Zealand triplefin fishes (Family Tripterygiidae) are an ideal model system to study speciation in the sea, as they conform to the criteria of an adaptive radiation, being philopatric, speciose and abundant, and having largely sympatric distributions. This thesis investigates two key aspects of the New Zealand triplefin radiation: 1) which ecological traits are under selection?; and 2) which traits are potentially available for the development of assortative mating? Habitat use was identified as a possible key trait for selection and investigated in detail in this thesis. Habitat use of the majority of New Zealand triplefin species was censused quantitatively throughout most of their latitudinal range and analysed using novel statistical methods. Analyses showed that habitat use was highly divergent between species and thus diversification in habitat may have been a major component in the evolution of this clade. The phylogenetic analysis of habitat characters confirmed that there has been rapid evolution in habitat use among species. Habitat selection at settlement was highly species-specific, indicating that interspecific differences in adult habitat use may be the outcome of active habitat choice established at settlement. These species-specific habitat associations showed no evidence for geographic variation in habitat use. Laboratory trials and field observations of the sister-species pair Ruanoho decemdigitatus and R. whero showed that competition was linked with body size, with R. decemdigitatus being the larger and consequently dominant species. The second part of this thesis investigated which traits may have contributed to prezygotic isolation, and thus to assortative mating. Little evidence was found for divergence in breeding season or male colour patterns. However, divergence in habitat affected breeding habitat choice, as triplefins court and mate in the same territory as that occupied year round. This suggests that assortative mating in New Zealand triplefin species could be the by-product of adaptation to habitat resources. Body size affected mate choice and time at first maturity in the Ruanoho sister-species pair, suggesting that size is important in the maintenance of reproductive isolation in these species. Differences in body size may have also lead to assortative mating in other New Zealand triplefin sister-species pairs, as all sister-species pairs differ in maximum body size. The findings of this thesis invoke a strong role for ecologically-based selection in speciation, and support the hypothesis that adaptation to habitat has been a major factor in speciation in this system. / This PhD was funded by the New Zealand Royal Society (Marsden Fund 02-UOA-005 to Kendall Clements), the Tertiary Education Commission (Top Achiever Doctoral Scholarship), and the University of Auckland (University of Auckland Doctoral Scholarship.
346

Ecological factors associated with speciation in New Zealand triplefin fishes (Family Tripterygiidae)

Wellenreuther, Maren January 2007 (has links)
Theoretical research has demonstrated that ecological interactions in sympatry or parapatry can generate disruptive selection that in concert with assortative mating can lead to speciation. However, empirical examples are few and restricted to terrestrial and lacustrine systems. New Zealand triplefin fishes (Family Tripterygiidae) are an ideal model system to study speciation in the sea, as they conform to the criteria of an adaptive radiation, being philopatric, speciose and abundant, and having largely sympatric distributions. This thesis investigates two key aspects of the New Zealand triplefin radiation: 1) which ecological traits are under selection?; and 2) which traits are potentially available for the development of assortative mating? Habitat use was identified as a possible key trait for selection and investigated in detail in this thesis. Habitat use of the majority of New Zealand triplefin species was censused quantitatively throughout most of their latitudinal range and analysed using novel statistical methods. Analyses showed that habitat use was highly divergent between species and thus diversification in habitat may have been a major component in the evolution of this clade. The phylogenetic analysis of habitat characters confirmed that there has been rapid evolution in habitat use among species. Habitat selection at settlement was highly species-specific, indicating that interspecific differences in adult habitat use may be the outcome of active habitat choice established at settlement. These species-specific habitat associations showed no evidence for geographic variation in habitat use. Laboratory trials and field observations of the sister-species pair Ruanoho decemdigitatus and R. whero showed that competition was linked with body size, with R. decemdigitatus being the larger and consequently dominant species. The second part of this thesis investigated which traits may have contributed to prezygotic isolation, and thus to assortative mating. Little evidence was found for divergence in breeding season or male colour patterns. However, divergence in habitat affected breeding habitat choice, as triplefins court and mate in the same territory as that occupied year round. This suggests that assortative mating in New Zealand triplefin species could be the by-product of adaptation to habitat resources. Body size affected mate choice and time at first maturity in the Ruanoho sister-species pair, suggesting that size is important in the maintenance of reproductive isolation in these species. Differences in body size may have also lead to assortative mating in other New Zealand triplefin sister-species pairs, as all sister-species pairs differ in maximum body size. The findings of this thesis invoke a strong role for ecologically-based selection in speciation, and support the hypothesis that adaptation to habitat has been a major factor in speciation in this system. / This PhD was funded by the New Zealand Royal Society (Marsden Fund 02-UOA-005 to Kendall Clements), the Tertiary Education Commission (Top Achiever Doctoral Scholarship), and the University of Auckland (University of Auckland Doctoral Scholarship.
347

Ecological factors associated with speciation in New Zealand triplefin fishes (Family Tripterygiidae)

Wellenreuther, Maren January 2007 (has links)
Theoretical research has demonstrated that ecological interactions in sympatry or parapatry can generate disruptive selection that in concert with assortative mating can lead to speciation. However, empirical examples are few and restricted to terrestrial and lacustrine systems. New Zealand triplefin fishes (Family Tripterygiidae) are an ideal model system to study speciation in the sea, as they conform to the criteria of an adaptive radiation, being philopatric, speciose and abundant, and having largely sympatric distributions. This thesis investigates two key aspects of the New Zealand triplefin radiation: 1) which ecological traits are under selection?; and 2) which traits are potentially available for the development of assortative mating? Habitat use was identified as a possible key trait for selection and investigated in detail in this thesis. Habitat use of the majority of New Zealand triplefin species was censused quantitatively throughout most of their latitudinal range and analysed using novel statistical methods. Analyses showed that habitat use was highly divergent between species and thus diversification in habitat may have been a major component in the evolution of this clade. The phylogenetic analysis of habitat characters confirmed that there has been rapid evolution in habitat use among species. Habitat selection at settlement was highly species-specific, indicating that interspecific differences in adult habitat use may be the outcome of active habitat choice established at settlement. These species-specific habitat associations showed no evidence for geographic variation in habitat use. Laboratory trials and field observations of the sister-species pair Ruanoho decemdigitatus and R. whero showed that competition was linked with body size, with R. decemdigitatus being the larger and consequently dominant species. The second part of this thesis investigated which traits may have contributed to prezygotic isolation, and thus to assortative mating. Little evidence was found for divergence in breeding season or male colour patterns. However, divergence in habitat affected breeding habitat choice, as triplefins court and mate in the same territory as that occupied year round. This suggests that assortative mating in New Zealand triplefin species could be the by-product of adaptation to habitat resources. Body size affected mate choice and time at first maturity in the Ruanoho sister-species pair, suggesting that size is important in the maintenance of reproductive isolation in these species. Differences in body size may have also lead to assortative mating in other New Zealand triplefin sister-species pairs, as all sister-species pairs differ in maximum body size. The findings of this thesis invoke a strong role for ecologically-based selection in speciation, and support the hypothesis that adaptation to habitat has been a major factor in speciation in this system. / This PhD was funded by the New Zealand Royal Society (Marsden Fund 02-UOA-005 to Kendall Clements), the Tertiary Education Commission (Top Achiever Doctoral Scholarship), and the University of Auckland (University of Auckland Doctoral Scholarship.
348

Ecological factors associated with speciation in New Zealand triplefin fishes (Family Tripterygiidae)

Wellenreuther, Maren January 2007 (has links)
Theoretical research has demonstrated that ecological interactions in sympatry or parapatry can generate disruptive selection that in concert with assortative mating can lead to speciation. However, empirical examples are few and restricted to terrestrial and lacustrine systems. New Zealand triplefin fishes (Family Tripterygiidae) are an ideal model system to study speciation in the sea, as they conform to the criteria of an adaptive radiation, being philopatric, speciose and abundant, and having largely sympatric distributions. This thesis investigates two key aspects of the New Zealand triplefin radiation: 1) which ecological traits are under selection?; and 2) which traits are potentially available for the development of assortative mating? Habitat use was identified as a possible key trait for selection and investigated in detail in this thesis. Habitat use of the majority of New Zealand triplefin species was censused quantitatively throughout most of their latitudinal range and analysed using novel statistical methods. Analyses showed that habitat use was highly divergent between species and thus diversification in habitat may have been a major component in the evolution of this clade. The phylogenetic analysis of habitat characters confirmed that there has been rapid evolution in habitat use among species. Habitat selection at settlement was highly species-specific, indicating that interspecific differences in adult habitat use may be the outcome of active habitat choice established at settlement. These species-specific habitat associations showed no evidence for geographic variation in habitat use. Laboratory trials and field observations of the sister-species pair Ruanoho decemdigitatus and R. whero showed that competition was linked with body size, with R. decemdigitatus being the larger and consequently dominant species. The second part of this thesis investigated which traits may have contributed to prezygotic isolation, and thus to assortative mating. Little evidence was found for divergence in breeding season or male colour patterns. However, divergence in habitat affected breeding habitat choice, as triplefins court and mate in the same territory as that occupied year round. This suggests that assortative mating in New Zealand triplefin species could be the by-product of adaptation to habitat resources. Body size affected mate choice and time at first maturity in the Ruanoho sister-species pair, suggesting that size is important in the maintenance of reproductive isolation in these species. Differences in body size may have also lead to assortative mating in other New Zealand triplefin sister-species pairs, as all sister-species pairs differ in maximum body size. The findings of this thesis invoke a strong role for ecologically-based selection in speciation, and support the hypothesis that adaptation to habitat has been a major factor in speciation in this system. / This PhD was funded by the New Zealand Royal Society (Marsden Fund 02-UOA-005 to Kendall Clements), the Tertiary Education Commission (Top Achiever Doctoral Scholarship), and the University of Auckland (University of Auckland Doctoral Scholarship.
349

Uma contribui??o ao estudo das categorias internas e de sua prolifera??o em redes ARTMAP

Alves, Robinson Luis de Souza 05 November 2012 (has links)
Made available in DSpace on 2014-12-17T14:55:06Z (GMT). No. of bitstreams: 1 RobinsonLSA_TESE.pdf: 3429587 bytes, checksum: 6e34f5d59ebeb449eb13310ec5ff1eae (MD5) Previous issue date: 2012-11-05 / ART networks present some advantages: online learning; convergence in a few epochs of training; incremental learning, etc. Even though, some problems exist, such as: categories proliferation, sensitivity to the presentation order of training patterns, the choice of a good vigilance parameter, etc. Among the problems, the most important is the category proliferation that is probably the most critical. This problem makes the network create too many categories, consuming resources to store unnecessarily a large number of categories, impacting negatively or even making the processing time unfeasible, without contributing to the quality of the representation problem, i. e., in many cases, the excessive amount of categories generated by ART networks makes the quality of generation inferior to the one it could reach. Another factor that leads to the category proliferation of ART networks is the difficulty of approximating regions that have non-rectangular geometry, causing a generalization inferior to the one obtained by other methods of classification. From the observation of these problems, three methodologies were proposed, being two of them focused on using a most flexible geometry than the one used by traditional ART networks, which minimize the problem of categories proliferation. The third methodology minimizes the problem of the presentation order of training patterns. To validate these new approaches, many tests were performed, where these results demonstrate that these new methodologies can improve the quality of generalization for ART networks / As redes do tipo ART apresentam algumas vantagens: aprendizado online; converg?ncia em poucas ?pocas de treinamento; aprendizado incremental, etc. Contudo, alguns problemas existem: prolifera??o de categorias, sensibilidade a ordem de apresenta??o dos padr?es, escolha de um bom valor para o par?metro de vigil?ncia. O mais importante deles ? o problema da prolifera??o de categorias e ? provavelmente o mais cr?tico. Esse problema faz com que a rede crie v?rias categorias consumindo recursos (recursos para armazenar uma grande quantidade de categorias desnecess?rias impactando negativamente ou at? mesmo inviabilizando o tempo de processamento da rede) sem contribuir para a qualidade da representa??o do problema, ou seja, em muitos casos a quantidade excessiva de categorias geradas pelas redes ART faz com que a qualidade da generaliza??o da rede seja inferior. Outro fator que leva a prolifera??o de categorias das redes do tipo ART ? a dificuldade de aproximar regi?es de classes que tem geometria n?o retangular, ocasionando uma generaliza??o inferior a outros m?todos de classifica??o. A partir da observa??o desses problemas, foi desenvolvido esse trabalho que prop?e tr?s metodologias. Duas dessas metodologias utilizam uma geometria mais flex?vel do que a geometria regular retangular presente nas redes ART tradicionais e minimizam o problema da prolifera??o de categorias. A terceira metodologia minimiza o problema da ordem de apresenta??o dos padr?es e a prolifera??o de categorias. Com o objetivo de validar as novas abordagens, v?rios testes foram realizados. Os resultados obtidos nesses testes demonstram a viabilidade das metodologias propostas em reduzir o n?mero de categorias e melhorar a qualidade da generaliza??o. Em muitos desses testes a quantidade m?nima de categorias necess?rias para classificar corretamente as classes foi atingida ap?s o treinamento, o que demonstra uma significativa melhora em rela??o aos m?todos j? existentes. Al?m disso, devido a nova geometria das categorias, utilizando politopos convexos, a qualidade da generaliza??o melhorou em rala??o ao estado da arte
350

Evaluating methods for fire protection and related fire risk categories in rural towns of the Western Cape, South Africa

Myburgh, Erena 03 1900 (has links)
Thesis (MScEng)--Stellenbosch University, 2012. / ENGLISH ABSTRACT: Water flows required for fire protection (fire flows) from water distribution systems (WDS) in rural towns in the Western Cape Province, South Africa, were evaluated as part of this research project. The fire flow requirements specified in different South African guidelines, as well as a number of international standards, were compared. Various guidelines and codes used in South Africa, including the South African National Standards, specify fire flow requirements according to the risk category of the area concerned. Alternative methods of firefighting and new firefighting technologies that can reduce the reliance on potable water resources for firefighting were evaluated. The traditional method of designing a WDS to provide potable water for firefighting, commonly employed in South African municipal areas formed the focus of the study. The potential fire risk costs (potential costs of damages if a fire was to occur) should also be considered, in addition to the network construction costs, when designing a WDS, in order to determine the most economically feasible option. Data obtained from the fire departments of three municipalities in rural towns of the Western Cape, was analysed to determine the actual flow rates that were required to extinguish fires in these towns. The records considered covered approximately one year in each case and included a total of 564 fire incident reports suitable for this study. According to the data, a small fraction (11%) of the fires was extinguished using water from the WDS by connecting firefighting equipment directly to a fire hydrant. The majority of the fires were extinguished by means of water ejected from a firefighting vehicle. This method implies the use of water drawn from the potable network at a certain location; the water is shuttled by firefighting vehicles, from either the fire station or from a central abstraction point in the WDS. The location of the said abstraction point was found to have a notable impact on the WDS and this received attention in this study. The data showed that 99.8% of the flows required in rural towns were lower than the flows recommended for moderate risk areas in typical South African guidelines. Hydraulic modelling of a hypothetical WDS model was conducted to illustrate that the provision of fire flows according to commonly used South African fire flow standards leads to higher costs. The latter hypothetical case study illustrates that designing a network to provide fire flows according to the referred standards resulted in 15% higher costs, compared to designing a network that would have provided for the actual recorded fire flows according to the data set obtained from the selected rural towns compiled for this study. The hypothetical case study also showed that the cost for a WDS, where sufficient pressure is required at all hydrants during peak fire flows, is 2.4% higher than the cost for a distribution system where water is supplied via predetermined hydrants for refilling firefighting vehicles. A WDS with central, predetermined abstraction points for refilling firefighting vehicles offers a solution to providing fire flows in areas where the distribution systems may be inadequate. The revision of the current fire flow standards of South Africa would, therefore, be a logical next step along with the reassessment of methods used for supplying fire flows. / AFRIKAANSE OPSOMMING: Water vloei vir brandbestryding (brandvloei) uit waterverspreidingstelsels (WVS) in plattelandse dorpe in die Wes-Kaap, Suid Afrika, is as deel van hierdie navorsingsprojek geëvalueer. Die brandvloei soos gespesifiseer in verskillende Suid-Afrikaanse riglyne, asook ʼn aantal internasionale standaarde is vergelyk. Verskeie riglyne en kodes wat in Suid-Afrika gebruik word, insluitende die Suid-Afrikaanse Nasionale Standaarde, spesifiseer brandvloei-vereistes op grond van die risiko-kategorie van ʼn spesifieke gebied. ʼn Verskeidenheid alternatiewe metodes vir brandbestryding en nuwe brandbestrydings-tegnologieë is ondersoek, om sodoende die afhanklikheid van ons beperkte drinkbare waterbronne vir brandbestryding te verminder. Die tradisionele metode om water aan munisipale areas te voorsien, die gebruik van ʼn WVS, is ook geassesseer. Hierdie metodes dui daarop dat die potensiële brandgevaar-kostes (potensiële koste van skade indien ʼn brand sou plaas vind) ook in ag geneem moet word, tesame met die konstruksie kostes van ʼn WVS, om sodoende die mees ekonomies haalbare netwerk te bepaal. Data wat verkry is vanaf die brandweer departement van drie plattelandse munisipaliteite in die Wes-Kaap is ontleed om die werklike vloei-tempos vas te stel wat nodig was om brande te blus in hierdie dorpe. Die data is verkry vir ʼn tydperk van een jaar en 564 brandverslae was bruikbaar vir die doeleindes van hierdie studie. Volgens die data was ʼn lae aantal (11%) van die brande geblus vanuit die WVS deur die koppeling van brandbestrydingstoerusting direk aan ʼn brandkraan. Die meeste van die brande is geblus met behulp van water wat voorsien is deur ʼn brandbestrydingsvoertuig. Met hierdie metode word water deur die brandbestrydings-voertuie aangery vanaf die brandweerstasie of onttrek vanuit ʼn sentrale ontrekkingspunt in die WVS. Daar is gevind dat die ligging van laasgenoemde ontrekkingspunt ʼn beduidende impak op die WVS het – hierdie aspek is daarom verder ondersoek. Die data het getoon dat 99.8% van die vloei-tempo’s wat nodig is om brande te blus in plattelandse dorpe, laer is as die brandvloei riglyne vir matige risiko-areas volgens tipes Suid-Afrikaanse standaarde. Hidrouliese modellering van ʼn hipotetiese WVS is uitgevoer om te illustreer dat die verskaffing van brandvloei volgens die standaarde wat algemeen gebruik word, hoër kostes tot gevolg het. Die laasgenoemde hipotetiese gevallestudie illustreer dat ʼn netwerk ontwerp om brandvloei te verskaf volgens die huidige standaarde 15% duurder is as vir netwerke wat ontwerp is om die werklike aangetekende brandvloei te voorsien soos getoon deur die veld-data wat vir hierdie studie verkry is. Die hipotetiese gevallestudie het ook getoon dat die koste vir ʼn WVS, waar voldoende drukke gehandhaaf moet word by alle brandkrane terwyl piek brand vloeie voorsien word, 2.4% duurder is as vir ʼn WVS waar die brandvloei verskaf word by voorafbepaalde brandkrane vir die hervulling van brandbestrydingsvoertuie. ʼn WVS met sentrale onttrekkingspunte vir die hervulling van brandbestrydingsvoertuie, bied ʼn metode om brandvloei te voorsien in gebiede waar die WVS onvoldoende is, bv. informele nedersettings. Die hersiening van die huidige brandvloei standaarde van Suid Afrika sou dus ʼn logiese volgende stap wees, tesame met die herevaluering van die metodes wat gebruik word vir die verskaffing van brandvloei.

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