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Espinoza, David Nicolas. "Carbon geological storage - underlying phenomena and implications." Diss., Georgia Institute of Technology, 2011. http://hdl.handle.net/1853/42701.
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The dependency on fossil fuels faces resource limitations and sustainability concerns. This situation requires new strategies for greenhouse gas emission management and the development of new sources of energy. This thesis explores fundamental concepts related to carbon geological storage, including CO2-CH4 replacement in hydrate-bearing sediments. In particular it addresses the following phenomena:
- Interfacial tension and contact angle in CO2-water-mineral and CH4-water-mineral systems. These data are needed to upscale pore phenomena through the sediment porous network, to define multiphase flow characteristics in enhanced gas recovery operations, and to optimize the injection and storage CO2 in geological formations.
- Coupled processes and potential geomechanical implications associated to CH4-CO2 replacement in hydrate bearing sediments. Results include physical monitoring data gathered for CH4 hydrate-bearing sediments during and after CO2 injection.
- Performance of cap rocks as trapping structures for CO2 injection sites. This study focuses on clay-CO2-water systems and CO2 breakthrough through highly compacted fine-grained sediments. Long term experiments help evaluate different sediments according to their vulnerability to CO2, predict the likelihood and time-scale of breakthrough, and estimate consequent CO2 leaks.
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Karlsson, Emil, and Pettersson Anja. "Modifierad konstruktion av plastkapsyl för förbättrad tätning." Thesis, Linnéuniversitetet, Institutionen för maskinteknik (MT), 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-104879.
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För att motverka att innehållet i en behållare läcker ut krävs det att förslutningen är tät. För att förhindra läckage används någon form av tätning. På kapsyler i plast integreras ofta tätande element direkt i kapsylen i form av läppar eller kanter som pressar mot flaskan.Studien berör den inbyggda tätningen på en ”push-on”-kapsyl i Polypropencopolymer. Kapsylen tillverkas av Emballator Växjöplast AB och kallas DLM (dropless medicine) då den i de flesta fall monteras på glas- eller plastflaska som innehåller medicin. Kapsylens underdel pressas på flaskan permanent och den tvådelade kapsylen fungerar genom att en separat överdel skruvas på underdelen.Studien innehåller produktutvecklingssteg för att ta fram en uppdaterad konstruktion som ska klara av de problem som flaskans profil medför. Studien är upplagd som en DRM-studie och försöker svara på vad som påverkar tätningsförmågan hos en kapsyl och hur de tätande elementen kan konstrueras för att neutralisera flaskans form. Problemen uppstår främst när kapsylen är monterad på glasflaskan och roteras, då flaskan i vissa fall har en något oval profil. Det är när flaskan roteras som tätningen inte anpassar sig tillräckligt fort för att bli tät igen. Genom arbetets gång har man insett att i stället för att forma tätningen så att den följer behållarens form fortare, och riskera plastisk deformation på grund av relaxation hos materialet, väljer man att placera ytterligare en tätning på toppen. Ytan på toppen av flaskan utnyttjas, eftersom det är en ledig yta på både kapsyl och flaska,för att tätningarna ska komplettera varandra. Det görs för att kunna ha kvar den nuvarande tätningen och endast addera en topptätning som är mindre känslig för ovalitet hos flaskan. Studiens resultat bör ses som underlag för framtagning av prototyper och testning, då det inte går att garantera konstruktionens duglighet utan fortsatt testningTo prevent the contents of a container from leakage the closure of the container mustbe sealed. Some kind of seal is used to prevent leakage. The sealing part of plastic caps is usually integrated in the design of the cap in form of lips or edges that areputting pressure against the bottle.The study refers to the integrated seal on a “push-on” cap that is made of Polypropylene copolymer. The cap is manufactured by Emballator Växjöplast AB and is called DLM (dropless medicine) since it is mounted to a glass or plastic bottle containing medicine in most cases. The bottom part of the cap is pressed onto the bottle permanently and the two-part design works through a separate top part that is screwed onto the bottom part.The study contains product development steps to create an updated design that manages the problems caused by the profile of the bottle. The study is laid out as a DRM-study that is trying to answer what is affecting a cap´s ability to seal and how the sealing elements can be designed to neutralize the shape of the bottle. The problems are appearing mostly when the cap is mounted to the glass bottle and is rotated, since the bottle in some cases has an oval profile. It is when the bottle is rotated that the seal is not adapting fast enough to become sealed again.Through the process of the study, it has been realized that it is better to place a second seal on top of the bottle instead of designing a seal that follows the shape of the container. This is done to reduce the risk of plastic deformation due to relaxation of the material. The surface at the top of the bottle is utilized, since it is an unoccupied space at both the cap and the bottle, to have the seals complete each other. This is done to be able to keep the current seal and just add a top-seal that is less sensitive for ovality of the bottle. The results of the study should be seen as a basis for production of prototypes and testing since it not possible to guarantee the capability of the design without continued testing.
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Engström, Joel. "A lone SEAL : What Failure can tell us." Thesis, Försvarshögskolan, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:fhs:diva-9965.
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Special operations are conducted more than ever in modern warfare. Since the 1980s they have developed and grown in numbers. But with more attempts of operations and bigger numbers, comes failures. One of these failures is operation Red Wings where a unit of US Navy SEALs attempted a recognisance and raid operation in the Hindu Kush. The purpose of this paper was to see how that failure could be analysed from an existing theory of Special operations. This was to ensure that other failures can be avoided but mainly to understand what really happened on that mountain in 2005. The method used was a case study of a single case to give an answer with quality and depth. The study found that Mcravens theory and principles of how to succeed a special operation were not applied during the operation. The case of operation Red Wings showed remarkable valour and motivation, but also lacked severely when it came to simplicity, surprise, and speed.
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Fernández, Cranz Matías, and Hampus Olsson. "Design and development of a power seat structure for a sports car." Thesis, Högskolan i Halmstad, Akademin för företagande, innovation och hållbarhet, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-44880.
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The purpose of this thesis is to develop a power seat structure that can serve as an alternativeto the one developed by Koenigsegg for their upcoming model Gemera and potentially others.The power seat structure will be designed around an existing chassis and will use it as areference to create an accommodating power seat structure. It will be designed to be used witha fixed-back seat that is used in the development process of the Gemera.Koenigsegg requires that the power seat structure allows for horizontal and lifting motion, aswell as tilting. These functions will be adapted to the power seat structure designed by theproject group.Due to confidentiality concerns, some parts of this thesis will not be made available to thepublic.
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Santos, Hélder Guimarães de Oliveira. "Portuguese sell-side analysts' reports: can they deliver?" Master's thesis, Universidade de Aveiro, 2011. http://hdl.handle.net/10773/7878.
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Mestrado em GestãoThis paper studies the importance of Portuguese financial sell-side analysts’ reports by testing reliability in firms’ Price Target calculation and information aptitude (deliver ability) in the content of sell-side analysts’ reports. The importance of sell-side analysts reports has long been studied, mainly in two different perspectives: the consequences of their work (market price reactions, trading strategies based in analysts’ recommendations) and the externalizations that influence their work (herding and bias behaviors). We believe that before either perspective can explain their value, analysts through their reports should be able to deliver the information users need and offer coherent calculation that justifies the Price Targets. We explore and encode the complete content of 73 reports from PSI20 listed companies, and apply consistency and reliability procedures to test them. Informativeness is tested against an ideal report (built mainly from the Jenkins Report conclusions). To test reliability in the Prices Targets calculations we investigate if the method and the parameters of the evaluation are clearly disclosed and if the calculative procedure is according to the theoretical conventions.
O presente trabalho propõe-se avaliar a importância dos analistas financeiros Portugueses testando para isso a fiabilidade no cálculo dos Price Targets e a capacidade informativa dos relatórios que produzem. A utilidade dos analistas financeiros tem sido há muito estudada, por norma através de duas perspectivas: avaliando as consequências do seu trabalho (reacção dos mercados às suas recomendações e estratégias de investimento baseadas nessas mesmas recomendações) e por outro lado considerando as variáveis exógenas que influenciam o seu trabalho (comportamentos tendenciosos e de “arrebanhamento”). Acreditamos que antes de avaliar a pertinência destas perspectivas, importa averiguar se através dos relatórios que produzem os analistas financeiros fornecem a informação que os seus utilizadores necessitam. Para isso examinamos e codificamos 73 relatórios financeiros de empresas que integram o PSI20, testando-os em termos de informatividade e fiabilidade. A capacidade informativa é testada em confronto com um relatório ideal (baseado nas conclusões do Relatório Jenkins). Para testar a confiabilidade no cálculo dos Price Targets investigamos se o método e os parâmetros utilizados são expressos com clareza e se o processo de cálculo está em conformidade com aquilo que são os princípios teóricos aceites.
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Abrakasa, Selegha. "Leakage through petroleum cap rocks : UK and the Norwegian sectors of the North sea." Thesis, University of Newcastle Upon Tyne, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.500909.
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The study on caprock leakage in the North Sea consists of two aspects: first, leakage as Indicated by thermogenic wet gas, which was a survey study comprising the UK and Norwegian North Sea on fifty wells in forty fields. The second, a case study on Valhail well 2/8-8, which dealt with the geochemical evaluation of the caprock for leaked petroleum and the petrophysical characterization of the caprock. The result of the survey study indicate that thermogenic wet gas can serve as a reliable and diagnostic indicator of caprock leakage. High wet gas heights (i.e. ̲> lOOOm) were observed for fractured caprocks of high pore pressured reservoirs.
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Vasconcelos, MÃrcio Anderson Guedes. "Estudo sobre o emprego do CAPE SEAL em revestimentos rodoviÃrios do estado do CearÃ." Universidade Federal do CearÃ, 2013. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=10934.
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CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel SuperiorOs tratamentos de superfÃcie se apresentam como um dos tipos de revestimentos asfÃlticos mais aplicados em pavimentos flexÃveis nas rodovias brasileiras. Isso se deve a sua utilizaÃÃo na construÃÃo de rodovias de baixo e mÃdio volume de trÃfego, bem como na conservaÃÃo e manutenÃÃo de pavimentos existentes. Dentre os tratamentos de superfÃcie, destacam-se o Tratamento Superficial Simples (TSS) e Duplo (TSD), que juntos representam 63% da malha rodoviÃria pavimentada do estado do CearÃ, e o Microrrevestimento AsfÃltico (MRAF), cuja aplicaÃÃo tem crescido ao longo dos anos. A junÃÃo do TSS e MRAF à conhecida como Cape Seal (CS) e tem como diferencial reunir caracterÃsticas de ambos os tratamentos, entretanto, sem aplicaÃÃo conhecida em rodovias cearenses. A dissertaÃÃo tem como objetivo geral desenvolver um programa experimental que avalie o desempenho do CS em laboratÃrio para um agregado mineral (AM) e um agregado siderÃrgico (AS). Na metodologia desenvolvida no estudo, dividiu-se o programa laboratorial em quatro procedimentos experimentais que conduziram o desenvolvimento da pesquisa desde a caracterizaÃÃo dos materiais utilizados, moldagem e dosagem dos corpos de prova, atà a realizaÃÃo dos ensaios de desempenho e avaliaÃÃo dos pavimentos testados em um simulador de trafego de laboratÃrio. Os resultados da caracterizaÃÃo do AS atenderam com seguranÃa aos parÃmetros recomendados pelas especificaÃÃes tÃcnicas. Os corpos de prova confeccionados com agregado siderÃrgico e submetidos ao simulador de trÃfego apresentaram resultados melhores do que o agregado mineral quanto à avaliaÃÃo ao desgaste, deformaÃÃo e rugosidade, indicando assim a potencialidade do AS em tratamentos do tipo CS e TSD. Observou-se, diante do programa experimental executado, que o cape seal quando comparado ao TSD atravÃs de parÃmetros tÃcnicos e econÃmicos, apresentou uma melhor capacidade de absorÃÃo de cargas, maior qualidade de rolamento e menor desgaste. Entretanto, quanto ao aspecto de custos, a aplicaÃÃo do CS deve ser analisada cuidadosamente diante da viabilidade do projeto. Acredita-se que o cape seal seja aconselhÃvel para rodovias que necessitem de um revestimento de melhor qualidade quando comparado ao TSD
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Wickens, Patricia Anne. "Interactions of the South African fur seal and fisheries in the Benguela ecosystem." Doctoral thesis, University of Cape Town, 1989. http://hdl.handle.net/11427/22566.
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Bibliography: pages 168-180.This thesis adopts an holistic approach to evaluation of the "seal problem", which encompasses the operational and biological interactions between the South African fur seal and fisheries in the Benguela Ecosystem. The operational interactions are examined using a qualitative assessment, and speculative, single-species simulation models are developed to improve understanding of seal population dynamics, present options for seal management and explore seal-fishery interactions. The models show that the probability of a seal living longer than 20 years is 14%; that the population has increased at a rate of 5.1 % p.a. since the last major census in 1983; that in 1988 there were an estimated 1.5 million seals that consumed over 2 million tons of fish; that although seal population size is usually estimated by multiplying the number of pups by a factor of 4, this factor is very variable and under different culling regimes is usually greater than 4; that historically, the mean population : pup ratio is 4.55. The most effective means of reducing the population is to cull both pups and bulls (the population decrease resulting mainly from reduced pup production caused by disturbance during bull culling). Culling pups is the least effective means of population control. Culling cows alters the population sex ratio drastically and is considered undesirable. To achieve a small or negative population growth rate, more bulls and pups need to be culled than have been taken historically. Each of the fisheries is found to be subject to operational interactions with seals, this being most severe for the purse-seine fishery. The per capita consumption of fish by seals is similar under any management regime so it is not justified to adopt a particular culling strategy to reduce overall consumption. When either seal predation or fishing mortality is reduced, the model simulates an increase in fishery yield of Cape hakes. But there is inadequate understanding of hake population dynamics at present, and depending on the interactions between species, decreased predation may result in increased or decreased fishery yields. This study shows that operational interactions are a real problem and this biases the opinion of fishermen towards seals as competitors for fish resources.
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Bond, Katherine J. "Mudstone cap rocks as vertical migration pathways : case studies from the Norwegian sector of the North Sea." Thesis, University of Newcastle Upon Tyne, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.366524.
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Lloyd, Jeremy. "The palaeoceanography and glacial history of the Greenland Sea and Spitsbergen Ice Cap over the last 200ka." Thesis, University of Edinburgh, 1994. http://hdl.handle.net/1842/12450.
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Piston cores from the continental slope of Spitsbergen were analysed using micropalaeontological, stable isotope and sedimentological techniques. The attempted to determine the palaeoceanographic history of the Norwegian-Greenland Sea, and the glacial history of the Spitsbergen ice cap over the last 200ka. The chronostratigraphy of the cores was determined using stable oxygen isotope analysis of planktic foraminifera. These records were correlated to a composite benthic foraminiferal δ18 O stratigraphy from the Norwegian Sea (Duplessy et al., 1988), as well as to other radiometrically dated records from the Norwegian-Greenland Sea to produce an age model. X-ray photographs were used to assess the ice rafted detrital (IRD) content of the cores, dropstones were counted from these x-rays. IRD content was used as a measure of calving rate from the outlet glaciers of the Spitsbergen ice cap. From these counts and the δ18O record a model of relative advance and retreat of the Spitsbergen ice cap was produced. It was found that moisture supply was the over riding factor controlling dropstone input to the Spitsbergen margin. Periods of high moisture supply led to rapid ice advance and hence high calving rate producing peaks in IRD. Peak IRD events were found during interstadial periods, such as substage 5c, as well as during glacial periods when ice was at the shelf edge, and during deglacial periods. Absolute abundance counts of foraminifera suggest glacial periods had a much higher productivity than interglacial periods. This strongly suggests the Spitsbergen margin was at least seasonally ice free during glacial periods. Melting events were recognised from the δ18O record of planktic and benthic foraminifera. The influx of North Atlantic surface waters during deglaciation has been identified from the δ18O record and the faunal assemblages. The initial influx of North Atlantic water during the last deglaciation took place at about 12.3ka, disappeared at 12ka, was present again from 10.5 to 10.3ka, and then from 10ka onwards.
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Goh, Jeffrey Mau Seong. "The principles and policies of regulating airline competition." Thesis, University of Sheffield, 1999. http://etheses.whiterose.ac.uk/6030/.
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Regulation in its generic sense has existed for a very long time in different forms, with different aims and different problems of accountability, but the study of competition regulation by a Government agency has perhaps become fashionable only in recent years. This thesis consists of two leading themes. First, it will contend that, whilst the market system has been seriously underestimated as a social institution to the extent that it should be left to operate and organise itself where that is possible, it is at the same time not always self-regulating. Residual intervention by the State or its agencies will remain necessary in strategic cases, either to protect individual autonomy and choice, or to correct failures of the market system. The question is simply more or less regulation. Secondly, and on that premise, competition regulation must be distinguished into economic regulation and antitrust regulation because the relationship between them is inversely proportional: the more intense economic regulation is, the less important antitrust regulation becomes. By implication then, economic liberalisation or deregulation must be accompanied by a robust framework of antitrust regulation to ensure that the conditions of sustainable competition are not threatened by anti-competitive practices. Conditions of sustainable competition are thus critical for market contestability. For many years, domestic and international airline competition has been the subject of comprehensive regulation. With the passage of time, however, the thinking has changed and, no doubt, liberal policies and practices will continue to find expression in future political and economic sentiments. The responsibility for regulating airlines in the United Kingdom falls on the Civil Aviation Authority, which has played a formidable role in transforming the policy of heavy regulation into minimal regulation, although much of that regulatory landscape has now been altered with the advent of the Single European Aviation Market. The experiences of, both, the CAA and the new SEATNI provide an illuminating account of the evolutionary process of regulating airline competition, that from economic to antitrust regulation.
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Khan, Sehra Y. "Can young people's emotional intelligence be promoted through the secondary school's Social and Emotional Aspects of Learning (SEAL) Programme?" Thesis, University of Southampton, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.533243.
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Nsanta-Kalimukwa, Natasha. "Trade liberalisation vs public morality : can the European Union seal ban be justified under the GATT Article XX (a)?" Master's thesis, University of Cape Town, 2014. http://hdl.handle.net/11427/12892.
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Includes bibliographical references.The objective of the research is to assess the strength of a potential exception available to the EU under Article XX (a) of the GATT. This is not the first time that issues to do with animal welfare are being challenged at the WTO dispute settlement system. Animal welfare issues have been at the centre of conflicts from the times of the GATT through to the creation of the WTO. For example, in 1993 a dispute arose when the U.S. adopted a law known as the U.S. Marine Mammal Protection Act which established standards of harvesting tuna using purse seine nets to prevent the unnecessary killing of dolphins. This law entailed that if a country exporting to the U.S. did not meet the standards as specified in the law, the tuna would be embargoed. The Panel ruled against the U.S although the panel report was never adopted because under the old GATT regime, a decision could be blocked by a member state that was unhappy with the decision and the U.S. blocked its adoption. This scenario is no longer possible because under the WTO because of the negative consensus principle. Further, in 1997, under the United States Endangered Act of 1973, the U.S. imposed a ban on the importation of certain shrimp and shrimp products that were not caught using turtle excluding devices (TED)in their nets when fishing in areas where there a significant likelihood of encountering sea turtles. Although the two cases were brought under Article XX (b) exception, they are still important for the seals case because the main reason the products were banned was because the countries who adopted the bans did not subscribe to the methods used in the hunting which raised concerns in their countries. Seals have also come under contention before when in 1983 the EU banned products from ‘whitecoats’ and bluebacks’ a species of seals also known as harp and hooded seals respectively that have not yet been weaned as a result of concerns over their conservation status. The current seal dispute is therefore important for two reasons. Firstly the study is ofparticular importance because the moral exception under GATT is rarely invoked. It will be the third dispute under the GATT specifically to invoke the public morals exception and the second dispute under the WTO. So there has not been a lot of adjudication on the exception. Secondly, it is the first time that a dispute panel at the WTO is adjudicating upon a trade measure adopted for the protection of animal welfare by a Member State purely based on moral beliefs and indignation.
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Muller, Cornelius Marthinus. "The phylogeographic population structure of the Cape sea urchin, Parechinus angulosus." Thesis, Stellenbosch : Stellenbosch University, 2011. http://hdl.handle.net/10019.1/6899.
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Thesis (MSc)--Stellenbosch University, 2011.ENGLISH ABSTRACT: South Africa's coastline is in the region of 3650kms and encompasses many different and dynamic marine environments. To enhance our current understanding of the population structure and gene flow patterns of intertidal zone marine species in this region, this study sets out to investigate the phylogeographic population structure of the Cape sea urchin, Parechinus angulosus, using mitochondrial and nuclear DNA sequence data collected in 2007 and 2008. Individuals were sampled from 18 geographic locations between southern Namibia and Durban, covering nearly the full extent of the species range. Sequence data were obtained from a 790bp region of the COI mtDNA gene (n=510) and a 182bp region of the nDNA SpREJ9 gene (n=145), respectively. The mtDNA data revealed 283 polymorphic sites (36%) defining 195 haplotypes, of which 160 were unique and 35 shared among individuals. Haplotype diversity (h) was found to be high both overall (h=0.95) and for individual localities (h=0.75-0.98), with nucleotide diversity (π) being low overall (π=0.013) as well as for individual localities (π=0.0033-0.0254). AMOVA revealed significant population structure among sampling sites in the Namaqua Province biogeographical region, as well as between three of the four respective coastal biogeographic provinces/regions. Gene flow was bi-directional among sampling sites in the south coast Agulhas and East Coast Province biogeographical regions, while gene flow in the Namaqua Province appears to be dominated by northwards movement. BAPS identified a significant break in the Cape Point region, which was also reflected in the gene flow patterns and parsimony networks. This broadly corresponds to previously identified biogeographic regions as well as genetic breaks for other marine species found along this coast. Fu's Fs statistics showed strong signal(s) of population expansion for individual sampling localities as well as for the data set as a whole, while MDIV estimated a time since expansion ranging from 7733-4759 years ago. The nDNA data revealed 54 variable sites (29.7%), defining 72 alleles of which 50 were unique and 22 shared among individuals. Many of the alleles (69.4%) were restricted to single sampling sites, with Betty's Bay on the south coast being the most diverse from a genetic viewpoint. Allelic diversity was high overall (h=0.86) while nucleotide diversity was low (π=0.025). No nuclear sub-group structure was identified by BAPS, although the parsimony network revealed shallow genetic structure between the Namaqua and Agulhas Provinces, with significant pairwise ФST values also recovered between their individual coastal localities. This points to at least one major barrier to gene flow for Parechinus angulosus along the South African coast, namely Cape Point. Several additional, smaller hindrances to gene flow along the coast were also identified, most of which are congruent with findings from studies on both other and sea urchin species. As a standalone study this research elucidated many aspects regarding the phylogeography of the Cape sea urchin, P. angulosus. However, it is when viewed in the broader context of invertebrate phylogeography along the southern African coastline that this research will provide its most critical insight.
AFRIKAANSE OPSOMMING: Geen opsomming
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Wilson, Rebecca A. "Social Emotional Learning Guarantee? How Ohio Can Move Beyond Adopting Sel Standards." Miami University / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=miami1615911161780767.
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Kounkou, Guy Ludovic. "Caractères, rythmes de mise en place, âge et signification paléogéographique des faciès d'une séquence sédimentaire de deep-sea fan : exemple du deep sea fan de cayar (Plaine abyssale du cap vert)." Perpignan, 1993. http://www.theses.fr/1993PERP0002.
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Grider, John Taylor. ""And I can live without going to sea": Pacific maritime labor identity, 1840--1890." Diss., Connect to online resource, 2006. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3219021.
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Nahon, Alphonse. "Évolution morphologique actuelle d'une flèche littorale holocène : le Cap Ferret, à l'embouchure du Bassin d'Arcachon." Thesis, Bordeaux, 2018. http://www.theses.fr/2018BORD0182/document.
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La flèche littorale du Cap Ferret s'est édifiée au cours des derniers 3 000 ans, à la faveur du ralentissement de l'élévation du niveau global des océans. Depuis 250 ans, les cartes marines révèlent une importante instabilité de l'extrémité libre de la flèche, à laquelle les travaux présentés dans ce mémoire tentent d'apporter une explication physique. Dans un premier temps le croisement des données cartographiques avec des données environnementales révèle la synchronisation des déplacements de la flèche avec d'une part l'Oscillation Nord Atlantique (NAO), et, d'autre part, les structuations décennales à multidécennales de la vitesse de l'élévation du niveau de l'Atlantique Nord-est. Les processus sous-jacents à cette synchronisation sont alors détaillés avec un modèle numérique de transport sédimentaire. Puis, l'érosion chronique de la flèche entre 1986 et 2016, ainsi que les mécanismes d'évolution de la plage océanique de la Pointe du Cap Ferret sont décrits et quantifiés à l'aide de données topographiques. A l'échelle locale, ces résultats apportent des preuves tangibles du rôle du climat dans l'érosion actuelle de la Pointe du Cap Ferret. D'un point de vue plus général, ces travaux contribuent à la meilleure description des processus contrôlant l'évolution des systèmes de barrières holocènes, dans le contexte actuel d'accélération de l'élévation du niveau de la merLow rates of global sea level rise have allowed the Cap Ferret coastal barrier-spit to develop since about 3 000 years ago. Over the last 250 years, navigation charts attest of a significant instability of the distal end of the spit, to which the present study aims to provide a physical explanation. First, the crossing of cartographic data with meteoceanic data reveals a strong relationship of the spit-end behaviour with, on the one hand, the North Atlantic Oscillation (NAO), and, on the other hand, decadal to multidecadal variations in the rate of sea level rise in the Northeast Atlantic. Underlying processes were then investigated using a numerical model for sediment transport. Finally, the chronic erosion of the spit between 1986 and 2016, as well as the evolution mechanisms of the oceanic beach of the spit-end are described and quantified by means of topographic data. Locally, these results support the role of climate in the ongoing erosion of the spit-end. From a wider perspective, this study brings new insigths on the processes controling the evolution of Holocene barrier systems, in the present context of an accelerating sea level rise
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Pettersson, Josefine, and Johanna Colling. "Analysis of Customisation in a Modular System : Development of a New Seat Solution." Thesis, Mälardalens högskola, Akademin för innovation, design och teknik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-44747.
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Today there is a shift from mass production to mass customisation due to changing customer needs in the global market. This thesis report analyses customisation in a modular system through a case study in the truck industry with focus on development of a new seat solution. The customer requests showed a demand for one to two additional seats in the cab. In order to answer to various customer needs, companies implement modular product development principals which enables them to produce in a rapid speed, minimize costs, increase performance and produce a high mix of products. The established RQ:s were: RQ1: How do companies improve competitiveness by translating customer needs into technical requirements? RQ2: What are the challenges and possibilities when making changes in a modular system? The thesis followed the first steps in the product development process due to delimitations in time, scope, and research quality. The data was collected through a literature study, interviews with customers and archival records and documentations at the case company. The study resulted in two final concepts, namely a seat solution and a bench solution which answered to the customer need of one to two additional seats in the cab. A conclusion was that it is crucial for companies to understand the in-depth customer needs to provide higher customer value, which in turn can contribute to strengthen the companies’ competitiveness. The correct translation of customer needs to technical requirements is essential for the development of a modular system. Challenges and possibilities when making changes in a modular system was found to be design complexity along with opportunity to reuse existing components. Both the translation of customer needs and design decisions regarding a modular system is achieved in the earlier stages of the product development process. It is thus of high importance to translate the customer needs correctly and make thoughtful decisions of the modules in the modular system to ensure company competitiveness.
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Ichida, Masahiro. "Developmental history of a Late Paleozoic Panthalassan sea-mount cap limestone with reference to fusulinoidean taphonomy: an example from the Atetsu Limestone, Southwest Japan." 京都大学 (Kyoto University), 2013. http://hdl.handle.net/2433/175130.
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Tshuma, Mengezi Chancellor. "An investigation of skills, knowledge and farmer support programmes of land reform beneficiaries :a case study of Forest Hill farmers in Kenton-on-Sea in the Ndlambe Local Municipality." Thesis, University of Fort Hare, 2013. http://hdl.handle.net/10353/d1013109.
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black owners by white colonialists. Even though whites made up less than 20% of the nation‟s population, they took more than 80% of the agriculturally productive land and drove the original owners to the unproductive reserves where they were cramped and could not practice agriculture at all. Various acts such as the Black Land Act of 1913, Development Trust Act of 1936 and the Native Laws Amendment Act of 1937 were introduced which further frustrated the displaced black population thereby plunging it deeper and deeper into poverty. The main objective behind the introduction of these acts was to restrain the black population from earning livelihoods through agriculture thus forcing them to offer their labour to white farmers for low wages just to earn some form of livelihood. Such unfair practices and distribution of land prompted the first democratically elected government of South Africa to embark on a drive to redistribute the nation‟s land equitably amongst its citizens to foster national reconciliation, stimulate economic growth and compensate those that were forced out or lost their land during the apartheid era. This initiative was called the Land Reform Programme (LRP) and was implemented with three prongs namely (i) land redistribution; (ii) restitution; and (iii) land tenure. Among the beneficiaries of the LRP were farmers from a community called Marselle in Kenton-on-sea. In addition to getting land for farming purposes, the Marselle farmers also obtained financial support from the government‟s Land Bank to help them kick-start their farming activities. However, in spite of such interventions, they have struggled to turn their activities into sustainable livelihood sources. One most likely cause for this is the lack of farming knowledge and skills needed to make them more efficient and productive. This study was thus geared towards evaluating the knowledge and skills gap in Marselle which, when addressed, could make the Marselle farmers more productive. Its focus was limited to the 32 livestock and 8 chicory farmers that are recognized members of their respective projects. Focus was limited only to these farmers since the next phase of this study will involve building their capacity based on the skills gaps identified through this study. The findings showed that the two projects benefited at least 130 individuals belonging to the farming households, with 67.5% of these households headed by males. The age of these farmers was equally shared at 40% each between those above 65 years and those that only went as far as fourth grade. No one went to tertiary at all. At least 75% of the investigated farmers were unemployed and 42% of this population was pensioners. In terms of income though, 64.98% of it was from external sources. The Masakhane Silime (Chicory) project was implemented to generate income and provide job opportunities for the locals but neither of these objectives had been met at the time the data for this study was collected due to various challenges like lack of funds and infrastructure to enhance productivity. Just like the chicory project, the livestock project had its own objectives, namely; to remove animals from the residential areas, provide the animals with a safe place, reduce road accidents and also to provide a livelihood source for local farmers. Due to overgrazing the pastures, lack of proper camps and other challenges, some effort still needs to be put to achieve these objectives. Even though the livestock project was formed with these objectives in mind, the farmers themselves reared livestock either for personal consumption, selling, ritual purposes, store of wealth or all these combined. Regarding technical skills, livestock farmers were found to rely mostly on indigenous knowledge sources to attain farming knowledge. Only animal healthcare knowledge was popular to more than half the respondents. This was said to be due to the focus group meetings held on the farm every other Wednesday to share information with local extension officers. In spite of these information sharing events, livestock farmers identified training on how to feed; market; handle; and treat their livestock as key intervention knowledge areas. Attendance to these focus group meetings was limited to livestock farmers only. Various socio-economic factors were also found to have some form of influence on the acquisition of livestock knowledge. Education was the most dominant factor, with a significant association with the farmers‟ feeding (p=0.033); animal healthcare (P=0.038); marketing (p=0.009); veld management (p=0.036); and cattle slaughtering (p=0.027) knowledge. Other variables most influential include the gender and age of the household head. The former was significant at 95% confidence level for farmers‟ feeding knowledge (p=0.021); animal healthcare (p=0.039); marketing (p=0.043); livestock housing and handling (p=0.023); veld management (p=0.018); and cattle slaughtering (p=0.043). The dominance of males in acquiring these skills could be explained by the fact that the majority of the livestock project members were males. The majority of the few female members became members by default after the passing on of their husbands but their participation in the project was done through other project members who looked after their animals on their behalf. The number of farming years also had some positive and significant influence on other knowledge areas such as feeding (p=0.021) and livestock housing and handling (p=0.013). The logic supporting this association is that farmers tend to accumulate new and more skills the longer they stay in the same enterprise. In addition, most of the interviewed farmers were farm labourers prior to relocating to Marselle hence they acquired the necessary knowledge long before the project started. Concerning the chicory project, its members also relied heavily on indigenous knowledge sources for farming knowledge. Soil preparation (24.1%); planting (20.7%); land care (24.1%); and mechanical weed control (48.3%) were the knowledge areas lacked by more than half the respondents. The farmers identified land preparation (75%); communication skills (25%); marketing (100%); financial management (62%); and harvesting (88%) as the key crucial intervention areas they needed prioritized. As a study meant to inform the capacity building phase of the Land Bank project, this study identified the existing skills gaps in the two projects implemented in Forest Hill. When implementing the Capacity Building (CB) phase, various socio-economic factors will have to be considered. For example, the proposed intervention should not discriminate against anyone on the grounds of gender or physical abilities. The skills introduced should also be simple enough to be accepted and acquired even by the illiterate, especially when one considers the high illiteracy levels amongst the respondents. Efforts should also be made to create partnerships with the right organizations or groups of people so that they provide the required expertise and resources for the benefit of the farmers as and when required.
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Brady, Mark. "Managing agriculture and water quality : four essays on the control of large-scale nitrogen pollution /." Uppsala : Dept. of Economics, Swedish Univ. of Agricultural Sciences, 2003. http://epsilon.slu.se/a369-ab.html.
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Casperson, Molly. "Walrus, Seal, and Seabird Faunal Remains from Summit Island in Bristol Bay, Alaska: The Subsistence Practices of Norton Peoples in an Island Environment (2740–980 Cal B.P.)." Thesis, University of Oregon, 2018. http://hdl.handle.net/1794/23116.
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The Norton Stage (2500-1000 cal B.P.) of the Norton Tradition is typically characterized as a caribou hunting and fishing culture, an idea developed by James Giddings through his formative work at the Iyatayet Site in Norton Sound. The concept of Norton fishers and caribou-hunters has been promoted by the long-term research of Don Dumond in the Naknek and Ugashik drainages on the Alaska Peninsula. While the northern Alaska Peninsula has historically productive salmon runs and abundant caribou populations, the concept that these taxa were essential to the Norton subsistence economy has not been critically evaluated. Giddings based his own assessment of Iyatayet subsistence practices on the animal harvest practices of contemporary Norton Sound Alaska Native communities, rather than directly from the faunal remains he identified during excavations.
Several faunal assemblages have been recovered from southwest Alaska, which provide the opportunity to test assumptions regarding Norton subsistence practices. Most of these assemblages come from the Bering Sea coast, a vastly different environment from more temperate coast of the Alaska Peninsula. In an effort to directly document Norton subsistence practices, I procured a sizeable faunal assemblage that Robert Shaw excavated in 1985 from 49-XHI-043 and 49-XHI-044. These sites are located on Summit Island, a nearshore island 6 km from the shoreline of northwest Bristol Bay.
Prior to my research, no analysis of the Summit Island collection had been conducted. As a result, an assessment of the faunal remains was not possible until I analyzed field notes to establish stratigraphic relationships and procured radiocarbon dates from the sites. I was able to confirm the presence of three discrete analytical components associated with Norton culture including Early Norton I (2740-2380 cal B.P.), Early Norton II (2400-2000 cal B.P.), and Late Norton (1390-980 cal B.P.). My analysis of 9,981 mammal and bird bone specimens resulted in the documentation of an intensive marine-focused subsistence economy. Over approximately 2,000 years, generations of Norton peoples harvested seals, walruses, murres, cormorants, and eiders from the Walrus Island chain. Terrestrial and riverine species were not well represented in the assemblage, despite the proximity of the mainland.
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Baisgård, Martin. "Multi-frequency backscattering from the sea floor; can the frequency response be used to identify typical sandeel grounds?" Thesis, Norwegian University of Science and Technology, Department of Electronics and Telecommunications, 2008. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-9782.
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In this report a phenomenological characterization technique of received bottom echoes has been developed and studied, to evaluate the potential of locating typical sandeel grounds. Data from a calibrated multi--frequency echosounder collected during a Survey Methods for Abundance Estimation of Sandeel (Ammodytes marinus) Stocks (SMASSC) survey in the sandeel fishing grounds of "Vestbanken" and "Elbow Spit North", were processed with developed scripts in Matlab to extract first received bottom echo parameters. Together with Simrad SEABEC results and sandeel samples, possible distinctive parameters were found for what could be sandeel grounds. However, ambiguities caused by ping to ping fluctuations and complex behavior of the sandeel species make the characterization difficult. Many of the calculated echo parameters showed possible discrimination power for a future multi-variate analysis.
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Le, Roux F. G. "The lithostratigraphy of Cenozoic deposits along the south-east Cape coast as related to sea-level changes." Thesis, Stellenbosch : Stellenbosch University, 1989. http://hdl.handle.net/10019.1/67134.
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Thesis (MSc)--University of Stellenbosch, 1989.AFRIKAANSE OPSOMMING: Senosoiese sedimente langs die suidooskus van die Kaapprovinsie is periodiek deur verskeie outeurs vir meer as 'n eeu bestudeer. In hierdie aanbieding word die Iiteratuur saamgevat en vele dubbelsinnige stratigrafiese onderverdelings en definisies opgeklaar. Die Senosoiese afsettings kan volgens oorsprong geklassifiseer word as marien, eolies en fluviaal. Die mariene afsettings, synde strand-, nabystrand-, estuarien of lagunale afsettings geassosieerd met transgressiewe/ regressiewe kusIyne, word nou op grond van kenmerkende litologiese, paleontologiese sowel as ouderdomsverskille onderverdeel in die Paleogeen Bathurst, Neogeen Alexandria en Kwaternere Salnova Foraasies. Die Laat-Plioseen tot Vroeg-Pleistoseen Nanaga Formasie, Middel- tot Laat- Pleistoseen Nahoon Formasie en die Holoseen Schel• Hoek Formasie vorm die kus-eoliese afsettings. AI die mariene en marienverwante (eoliese} formasies, gekenmerk deur kalkige klastiese afsettings, is saamgegroepeer in 'n nuutgedefinieerde Algoa Groep. Fluviale afsettings word onderverdeel in die Martindale, Kinkelbos, Bluewater Bay, Kudus Kloof en Sunland Formasies. Die onderskeie afsettings word gekorreleer met verskillende seevlakstande deur geologiese tye. Die vroegste Senosoiese transgressiewe/regressiewe siklus het in die Vroeg-Paleoseen begin en die hoogste aangetekende elevasie vir die era bereik. Die Bathurst Formasie is waarskynlik gedurende hierdie regressie afgeset. 'n Tweed~ kleiner transgressie/ regressiesiklus het plaasgevind gedurende die Laat-Eoseen tot Vroeg-Oligoseen. Sover tans bekend, kan geen afsetting in die dagsoomgebied van die Algoa Groep definitief met hierdie siklus in verband gebring word nie. Die volgende siklus, wat 'n transgressiewe maksimum van c. 250 m bereik het, het begin in die Middel-Mioseen en verstryk in die Vroee Plioseen. Mariene planasie van die kusplatform het gedurende die transgressie plaasgevind terwyl die Alexandria Formasie wat tans bo 120 m geleë is, gedurende die regressie afgeset is. Die Vroeg-Plioseen transgressie het waarskynlik 'n maksimum huidige hoogte van c. 120 m bereik, waartydens o.a. die 120 m branderstoep en "Humansdorpterras" gekerf is. Die Alexandria Formasie tans geleë tussen 60 en 120 m, is afgeset gedurende die Laat-Plioseen regressie. Hierdie regressie het verskeie relatief lang stilstande, wat waarskynlik die 106-m, 90- tot 100-m en 84-m branderstoepe verklaar, ondervind. Selfs die 60-m en 52-m kuslyne kon tydens hierdie regressie gevorm het. Voorlopige paleontologiese getuienis dui egter daarop dat die 60-m kuslyn 'n transgressiewe maksimum van 'n daaropvolgende siklus verteenwoordig, gevolg deur 'n regressie met minstens een beduidende stilstand by 52 m. Die Alexandria Formasie geleë tussen c. 60 en 30 m, is waarskynlik gedurende hierdie regressie gedeponeer, waartydens ook die Bluewater Bay, Kinkelbos en Kudus Kloof Formasies afgeset is. Gedurende die Kwaternêre transgressie/regressiesiklusse, waarvan minstens vier aangedui word, is die Salnova Formasie (afwesig bo 30 m) afgeset. Die Nahoon Formasie, wat ook op groot skaal op die kontinentale bank ontwikkel is, is gedeponeer gedurende die laaste twee Pleistoseen glasiale toe seevlakke tot benede -100 m gedaal het. Die Schelm Hoek Formasie wat tans nog afgeset word, het ontstaan uit die transgressiewe maksimum van die Flandriese transgressie aan die begin van die Holoseen.
ENGLISH ABSTRACT: Cenozoic sediments along the south-east coast of the Cape Province have been studied intermittently for more than a century by various authors. In this presentation the literature is reviewed and many ambiguous stratigraphic subdivisions and definitions are clarified. The Cenozoic deposits can be classified, according to origin, as marine, aeolian and fluvial. The marine deposits, being lagoonal deposits either beach, nearshore, estuarine or associated with transgressive/regressive shorelines, are now subdivided on the grounds of distinct lithological, palaeontological as well as age differences into the Palaeogene Bathurst, Neogene Alexandria and Quaternary Salnova Formations. The Late Pliocene to Early Pleistocene Nanaga Formation, the Hiddle to Late Pleistocene Nahoon Formation and the Holocene Schelm Hoek Formation constitute the coastal and marine-related aeolian deposits. All the marine (aeolian) formations, which are characterised by calcareous clastics, have been grouped together in a newly defined Algoa Group. Fluvial deposits are subdivided into the Martindale, Kinkelbos, Bluewater Bay, Kudus Kloof and Sunland Formations. The various deposits are correlated with different stands of sea-level through geological time. The earliest Cenozoic transgression/regression cycle started in the Early Palaeocene and reached the highest recorded altitude for the era. The Bathurst Formation was probably deposited during this regression. A second lesser transgression/regression cycle occurred in the Late Eocene to Early Oligocene. As far as is presently known, no deposit in the outcrop area of the Algoa Group can be definitely related to this cycle. The next cycle, which reached a transgressive maximum of c. 250 m, started in the Middle Miocene and terminated in the Early Pliocene. Marine planation of the coastal platform took place during the transgression, whilst the Alexandria Formation presently situated above 120 m, was deposited during the regression. The Early Pliocene transgression is considered to have reached a maximum present-day elevation of c. 120 m, during which the 120 m marine bench and "Humansdorp Terrace", amongst others, were carved. The Alexandria Formation presently situated between 60 and 120 m, was deposited during the Late Pliocene regression, which experienced several relatively long stillstands which probably account for the 106 m, 90 t.o 100 m and 8.4 m benches. Even the 60 m- and 52 m-shorelines could have been formed during this regression. Preliminary palaeontological evidence, however, suggests that the 60 m shoreline represents a transgressive maximum of a subsequent cycle followed by a regression with at least one significant stillstand at 52 m. The Alexandria Formation situated between c. 60 and 30 m, was probably deposited during this regression, which also saw the deposition of the Bluewater Bay, Kinkelbos and Kudus Kloof Formations. During the Quaternary transgression/regression cycles, of which at least four are indicated, the Salnova Formation (absent above 30 m) was deposited. The Nahoon Formation, which is also extensively developed on the continental shelf, was deposited during the last two Pleistocene glacials, when sea-levels receded to less than -100 m. The Schelm Hoek Formation, which is still being deposited, originated from the transgressive maximum of the Flandrian transgression at the start of the Holocene.
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Brockhurst, Veronica. "Development of novel DNA-based methods for the measurement of length polymorphisms (microsatellites)." Thesis, Queensland University of Technology, 2001.
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Claassens, Louw. "Aspects of the population ecology, habitat use and behaviour of the endangered Knysna seahorse (Hippocampus capensis Boulenger, 1900) in a residential marina estate, Knysna, South Africa: implications for conservation." Thesis, Rhodes University, 2018. http://hdl.handle.net/10962/54789.
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The Knysna seahorse Hippocampus capensis is South Africa’s only endemic seahorse species, and is found in only three adjacent estuaries along the southern coast. The conservation of this endangered species is important on a national and international level. This study presents the first research on this species within the Knysna estuary since 2001 and specifically focuses on aspects of its ecology within a residential marina estate (Thesen Islands Marina). The physico-chemical and habitat features of the marina were described and the population ecology, habitat use, and behaviour of the Knysna seahorse were investigated. Physico-chemical conditions within the western section of the marina, characterised by high water current velocities, were similar to that of the adjacent estuary. The eastern section of the marina was characterised by lower water current velocities and higher turbidity. Four major habitat types were identified within the marina canals: (I) artificial Reno mattress (wire baskets filled with rocks); (II) Codium tenue beds; (III) mixed vegetation on sediment; and (IV) barren canal floor. Seahorse densities within the marina were significantly higher compared to densities found historically within the estuary. Highest seahorse densities were specifically found within the artificial Reno mattress structures and within the western section of the marina. Seahorse density varied spatially and temporally and the type of habitat was an important predictor for seahorse occurrence. An experimental investigation found that H. capensis chooses artificial Reno mattress habitat over Zostera capensis when given a choice. GoPro cameras were used successfully to investigate daytime seahorse behaviour within the Reno mattress habitat. Seahorses were more active during the morning, spent most of their time (> 80 %) feeding, and morning courting behaviour for this species were confirmed. However, during the summer holiday period (mid-December to mid-January) few seahorses were observed on camera, which suggests that the increase in motor boat activity and the related increase in noise had a negative effect on H. capensis feeding and courting behaviour. The marina development, and in particular the Reno mattresses, created a new habitat for this endangered species within the Knysna estuary. In addition to the protection and restoration of natural habitats in which H. capensis is found, the conservation potential of artificial structures such as Reno mattresses should be realised.
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Grangier, Philippe. "Etude expérimentale de propriétés non-classique de la lumière; interférences à un seul photon." Phd thesis, Université Paris Sud - Paris XI, 1986. http://tel.archives-ouvertes.fr/tel-00009436.
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Ce mémoire décrit plusieurs expériences pour lesquelles la quantification du champ électromagnétique joue un rôle essentiel dans la description théorique et la compréhension physique des phénomènes observés. En particulier, la nécessité de cette quantification apparaît à travers la mise en évidence d'un état d'un champ très proche d'un état de Fock, dans lequel un seul quantum est excité (état à un seul photon). Un état à un seul photon peut être caractérisé en utilisant deux photomultiplicateurs placés de part et d'autre d'une lame semi-réfléchissante : la probabilité d'observer deux photodétections pendant un temps w doit être beaucoup plus petite que le produit des probabilités de photodétections simples pendant le même temps. Cette propriété "non-classique", que nous désignons par le terme d'anticorrélation, est mise en évidence expérimentalement pour une cascade radiative du Calcium, en utilisant des techniques de comptages rapides. Nous avons ensuite réalisé une expérience d'interférences, avec la lumière ayant permis d'observer l'effet d'anticorrélation. En utilisant un interféromètre de Mach-Zehnder réglé au voisinage de la teinte plate, le contraste mesuré des franges d'interférences a été supérieur à 98%, en parfait accord avec les performances calculées de l'interféromètre. Nous présentons enfin deux autres expériences, qui illustrent de façon plus générale la notion d'interférence à un photon : une expérience de battements quantiques dans une cascade radiative excitée de façon continue, et un effet d'interférence apparaissant dans la fluorescence d'un système de deux atomes, obtenus par photodissociation d'une molécule Ca2 par une impulsion laser.
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Jewell, Oliver Joseph David. "Foraging ecology of white sharks Carcharodon carcharias at Dyer Island, South Africa." Diss., University of Pretoria, 2012. http://hdl.handle.net/2263/30926.
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Dyer Island is thought to host one of the most abundant populations of
white sharks on the planet; this is often credited to the large (55 – 60,000) Cape fur
seal colony at Geyser Rock. Yet relatively little work has ever been produced from
the area. This may be attributed to the harshness in its location as a study site, exposed
to wind and swell from west to east which limits research periods. This study
accounts for over 220 hrs of manual tracking at Dyer Island with a further 68 added
from the inshore shallow areas of the bay. Sharks focused their movements and
habitat use to reefs or channels that allowed access to Cape fur seals. Movement-
Based Kernel Estimates (MKDE) were used to compute home range estimates for
shark movements through and around the heterogeneous structures of Dyer Island and
Geyser Rock. Inshore two core areas were revealed, one being the major reef system
at Joubertsdam and the other at a kelp reef where the tracked shark had fed on a Cape
fur seal. At Dyer Island one core area was identified in a narrow channel, ‘Shark
Alley’, here a second tracked shark foraged for entire days within meters of rafting
Cape fur seals.
Rate of Movement (ROM) and Linearity (LI) of tracks were low during daytime and
movements were focused around areas such as Shark Alley or other areas close to the
seal colony before moving into deeper water or distant reefs with higher rates of ROM
and LI at night. If moonlight was strong foraging would take place to the south of
Geyser Rock but with higher ROM and LI than observed during the day. Foraging
patterns in this study contrast studies from other sites in South Africa and home range
and activity areas were comparatively much smaller than observed in Mossel Bay. It has been established that several known white sharks forage at Dyer Island and the
other studied aggregation sites, such differences in foraging would suggest that they
are able to adapt their foraging behaviour to suit the environment they are in; making
them site specific in their foraging ecology.
Both satellite and acoustic telemetry are revealing aggregation hotspots of white
sharks in South Africa. It is important that such information is used to assist the
recovery of the species which has been protected since 1991, yet is rarely considered
in planning of coastal developments.Dissertation (MSc)--University of Pretoria, 2012.
Zoology and Entomology
MSc
Unrestricted
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Stewardson, Carolyn Louise, and carolyn stewardson@anu edu au. "Biology and conservation of the Cape (South African) fur seal Arctocephalus pusillus pusillus (Pinnipedia: Otariidae) from the Eastern Cape Coast of South Africa." The Australian National University. Faculty of Science, 2002. http://thesis.anu.edu.au./public/adt-ANU20030124.162757.
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[For the Abstract, please see the PDF files below, namely "front.pdf"] CONTENTS. Chapter 1 Introduction. Chapter 2 Gross and microscopic visceral anatomy of the male Cape fur seal with reference to organ size and growth. Chapter 3 Age determination and growth in the male Cape fur seal: part one, external body. Chapter 4 Age determination and growth in the male Cape fur seal: part two, skull. Chapter 5 Age determination and growth in the male Cape fur seal: part three, baculum. Chapter 6 Suture age as an indicator of physiological age in the male Cape fur seal. Chapter 7 Sexual dimorphism in the adult Cape fur seal: standard body length and skull morphology. Chapter 8 Reproduction in the male Cape fur seal: age at puberty and annual cycle of the testis. Chapter 9 Diet and foraging behaviour of the Cape fur seal. Chapter 10(a) The Impact of the fur seal industry on the distribution and abundance of Cape fur seals. Chapter 10(b) South African Airforce wildlife rescue: Cape fur seal pups washed from Black Rocks, Algoa Bay, during heavy seas, December 1976. Chapter 11(a) Operational interactions between Cape fur seals and fisheries: part one, trawl fishing. Chapter 11(b) Operational interactions between Cape fur seals and fisheries: part two, squid jigging and line fishing. Chapter 11(c) Operational interactions between Cape fur seals and fisheries: part three, entanglement in man-made debris. Chapter 12 Concentrations of heavy metals (Cd, Cu, Pb, Ni & Zn) and organochlorine contaminants (PCBs, DDT, DDE & DDD) in the blubber of Cape fur seals. Chapter 13 Endoparasites of the Cape fur seal. Chapter 14(a) Preliminary investigations of shark predation on Cape fur seals. Chapter 14(b) Aggressive behaviour of an adult male Cape fur seal towards a great white shark Carcharodon carcharias. Chapter 15 Conclusions and future directions.
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Magaldi, Marcello Gatimu. "Turbulent Coherent Structures Near Coastal Capes." Scholarly Repository, 2009. http://scholarlyrepository.miami.edu/oa_dissertations/226.
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A numerical study aimed at investigating the conditions under which different flow regimes appear near coastal capes is presented. The impacts of the regimes are also quantified in terms of integral quantities like mixing, current transport and form drag. Idealized and realistic numerical simulations are run both in barotropically and baroclinically-driven systems. The realistic cases model the Western Adriatic Current (WAC) in the Adriatic Sea. In both cases, the turbulent state of the flow is controlled in first approximation by the Burger number, Bu. When a steady barotropic and geostrophic current impinges on a triangular idealized cape, vertical movements are strong for Bu < 0.1 and pronounced lee waves can be found downstream of the obstacle. For 0.1 less than or equal to Bu < 1, fluid parcels flow more around the obstacle than over it. Flow separation occurs and small tip eddies start to shed. For Bu greater than or equal to 1, tip eddies merge to form larger eddies in the lee of the cape. Flow regimes are also strongly dependent on the obstacle slope alpha when Bu greater than or equal to 1. Flow regime diagrams in the Bu-alpha space are determined. A baroclinic current as the WAC becomes unstable in absence of wind as it separates from the coast for the presence of capes along its path. Downwelling favorable winds narrow and thicken the coastal buoyant current, raising Bu above a critical value and suppressing baroclinic instabilities. Upwelling favorable winds enhance instabilities via the opposite mechanism. With downwelling winds waters mix but remain relatively fresh (S less than or equal to 38), while most of the freshwater signal is lost with upwelling winds. The along-shore transport increases with downwelling winds while it decreases and can even reverse with upwelling winds. The form drag calculated across the obstacles in the different simulations is at least twice the magnitude of skin friction. In barotropic conditions it increases with increasing Bu and decreasing alpha and an empirical parametrization in the Bu-alpha space is put forth. Across the Gargano Promontory, more symmetric pressure fields are observed with downwelling winds; the form drag decreases as a result. The opposite is registered with upwelling winds.
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Cornaz, Natacha. "An analysis of the #AidToo movement on Twitter: What impacts can a hashtag achieve on sexual exploitation and abuse in the aid sector?" Thesis, Malmö universitet, Fakulteten för kultur och samhälle (KS), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:mau:diva-21819.
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Abuses and sexual misconduct have been present in the aid sector for decades. In 2013, a UN investigation declared sexual exploitation and abuse the most significant risk to UN peacekeeping missions. Nevertheless, the culture of impunity and hypocrisy still prevails in the aid sector. A recent report supports that one in three UN workers has been sexually harassed over the last two years. In the momentum of the #MeToo movement and of timely disclosures of various cases of sexual abuses and harassment in the international aid sector, people soon started to use the hashtag #AidToo on social media to highlight the prevalence of sexual harassment and misconduct within the industry. This study examines the major trends and the findings of an analysis conducted on the use of the hashtag #AidToo on Twitter over a ten-month period. As of the creation of the hashtag at the end of November 2017 and until the end of September 2018, over 13,000 tweets have used #AidToo in their content. Aid workers, journalists, NGOs, as well as news media compose the primary contributors of #AidToo tweets. Although limited to the political sphere and of limited reach, the movement has been sustainable and constant over its first year. Survivors and whistleblowers are the first to acknowledge that #AidToo has created a new safe space for discussion and has incited additional victims to speak up and share their experience. Aid organisations are now under constant scrunity, along with their values, integrity, and funding. However, the online campaign has mainly been a Northern conversation, and one can wonder if the use of the hashtag on Twitter failed to include the Global South and to give a voice to the actual victims of sexual exploitation and abuse. The #AidToo campaign represents a real and welcomed opportunity as a wake-up call for the aid sector, although it is too soon to observe the long-lasting impacts.
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Tortorelli, Brian Alfred. "Turtle Cam: Live Multimedia Interaction For Engaging Potential Visitor Population To Canaveral National Seashore." Master's thesis, University of Central Florida, 2012. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/5534.
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This project expands the outreach of the Canaveral National Seashore to its visitors, potential visitors, and virtual visitors through its goals in conservancy and preservation of its natural resources. This paper is involved with the current iteration of a series of digital media projects, the Sea Turtle Nest Camera, also known as, Turtle Cam. It details how and why this project was designed to be an ongoing initiative to assist in those goals.ID: 031001480; System requirements: World Wide Web browser and PDF reader.; Mode of access: World Wide Web.; Advisers: Cheryl Cabrera, Robb Lindgren, Robert Reedy.; Title from PDF title page (viewed July 16, 2013); Thesis (M.F.A.)--University of Central Florida, 2012.; Includes bibliographical references (p. 50-51).
M.F.A.
Masters
Visual Arts and Design
Arts and Humanities
Emerging Media; Digital Media
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Ray, Kacy Lyn. "Factors affecting Wilson's Plover (Charadrius wilsonia) demography and habitat use at Onslow Beach, Marine Corps Base Camp Lejeune, North Carolina." Thesis, Virginia Tech, 2011. http://hdl.handle.net/10919/30996.
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The Wilson’s Plover (Charadrius wilsonia) is a species of concern in most southeastern U.S. coastal states, where it breeds and winters. The U.S. Shorebird Conservation Plan listed this species as a Species of High Concern (Prioritization Category 4), and the U.S. Fish and Wildlife Service has designated it as a Bird of Conservation Concern (BCC). Despite its conservation status, Wilson’s Plover population trends are poorly understood and little research has been conducted examining habitat factors affecting this species’ breeding and foraging ecology. I collected Wilson’s Plover demographic data and explored which habitat characteristics influenced breeding success and foraging site selection among three coastal habitat types (i.e. fiddler crab (Uca spp.) mud flats, beach front, and interdune sand flats) at Onslow Beach, Marine Corps Base Camp Lejeune, North Carolina, 2008-2009. I observed little difference between years in nest success (≥ 1 egg hatched), failure, and overall nest survival. The majority of nest failures were caused by mammalian predators. For those nests that hatched successfully, greater proportions were located in clumped vegetation than on bare ground or sparsely vegetated areas. In-season chick survival for both years was higher for nests that hatched earlier in the season, and for nests farthest from the broods’ final foraging territory. Productivity estimates (chicks fledged per breeding pair) were not significantly different between years (0.88 ± 0.26 fledged/pair in 2008, 1.00 ± 0.25 fledged/pair in 2009) despite a shift in foraging behavior, possibly related to habitat alterations and availability in 2009. My findings indicate that Wilson’s Plover adults and broods were flexible in establishing final foraging territories; in 2008 all final brood foraging territories were on fiddler flats while in 2009, final foraging territories were sometimes split between fiddler flats, beach front, and interdune sand flats. For those Wilson’s Plovers establishing territories on fiddler flats, area of the flat was the most important feature explaining use versus non-use of a particular flat; area ≥ 1250 m² was preferred. Close proximity to water and vegetative cover were also important habitat features in foraging site selection on fiddler crab mud flats, and in all habitat types combined. My findings will directly contribute to population and habitat research goals outlined in the U.S. Shorebird Plan and will supplement limited data about foraging and habitat use related to Wilson’s Plover breeding ecology.Master of Science
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Natarajan, Nallusamy. "Ligands build on macrocyclic platforms : can the macro cyclic unit influence the catalytic properties ?" Thesis, Strasbourg, 2018. http://www.theses.fr/2018STRAF052.
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Cette thèse présente la synthèse de ligands originaux construits sur des plateformes coniques de type résorcin[4]arène ou calix[4]arène étant susceptibles de positionner un métal à proximité d'une unité réceptrice: a) des bis-binaphtylphosphites optiquement actifs dont les centres phosphorés ont été greffés sur le bord supérieur de cavités génériques. Ces coordinats ont été testés en hydroformylation asymétrique d’arènes vinyliques et ont conduit à une sélectivité iso très élevée avec de bons, voire très bons excès énantiomériques; b) des carbènes N- hétérocycliques ayant soit un, soit les deux atomes d'azote substitués par des unités résorcinarényle (variante cavitand) et leur utilisation pour la formation d'espèces comportant un centre métallique supramoléculairement piégé dans la partie cavitaire (complexes du type [NiXCpL] (X = Br ou Cl, Cp = cyclopentadiényle, LH = NHC). Ces complexes se sont avérés efficaces en dimérisation de l'éthylène; c) des carbènes N-hétérocyliques anormaux obtenus à partir de sels de triazolium comportant un ou deux substituants résorcinarène. Ces composés à fort encombrement ont été efficacement employés en couplage croisé de Suzuki-Miyaura entre des chlorures d'aryles volumineux et des acides arylboroniques stériquement encombrés. Les activités les plus importantes ont été obtenues avec le sel de triazolium stériquement le moins encombré, celui portant un seul substituant résorcinarène. Sa plus grande efficacité est due à une approche plus facile des substrats dans les intermédiaires catalytiques correspondants ainsi que de la présence de groupes pentyles flexibles pouvant interagir stériquement avec le centre métallique de manière à faciliter l'étape d'élimination réductriceThis thesis describes the synthesis of a series of compounds built on conical resorcin[4]arene and calix[4]arene platforms: a) diphosphites derived from optically active binol, in which the phosphite moieties have been grafted to the wider rim of the generic cones. These ligands were assessed in asymmetric hydroformylation of vinyl arenes and led to high iso selectivity with good to excellent enantiomeric excess; b) N-heterocyclic carbenes bearing either one or two cavitand moieties and their use for the synthesis of [NiXCpL] complexes (X = Br or Cl, Cp = cyclopentadienyl, LH = NHC) in which the NiCp moiety has been supramolecularly trapped in a resorcinarene bowl. These complexes were found active in ethylene dimerization; c) bulky triazolium salts with one or two resorcinarene substituents that were found suitable for the synthesis of complexes with abnormal NHCs. The latter were tested in palladium-catalysed Suzuki-Miyaura cross-coupling of bulky aryl chlorides with sterically hindered aryl boronic acids. Better activities were observed with the sterically less hindered triazolium salt, which bears a single resorcinarene substituent. Its higher efficiency arises from a higher substrate accessibility in the resulting catalytic intermediates as well as the presence of flexible pentyl groups that may interact with the metal centre so as to facilitate the reductive elimination step
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Gutierrez, Benjamin Thomas. "Relative sea-level rise and the development of channel-fill and shallow-water sequences on Cape Cod, Massachusetts." Thesis, Massachusetts Institute of Technology, 1999. http://hdl.handle.net/1721.1/55058.
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Thesis (M.S.)--Joint Program in Oceanography (Massachusetts Institute of Technology, Dept. of Earth, Atmospheric, and Planetary Sciences; and the Woods Hole Oceanographic Institution), 1999.Includes bibliographical references (leaves 60-63).
Channel-fill sediments located in shallow-water off the south shore of Cape Cod, Massachusetts, provide a record of the late-Pleistocene and Holocene geological evolution in a post-glacial setting. Though conventionally difficult to sample adequately and anticipated to have low preservation potential, channel-fill sequences record in some detail differing relative sea-level and sedimentation processes. Two distinct channel-fill sequences record differing sequence stratigraphies, and hence different origins and post glacial histories. These sequences have accumulated in channels eroded into two different late-Pleistocene glacial units. The first fill-type was encountered in channels on the upper portions of the channel network in northern half of the study site. Channels in this portion of the channel system were incised into the late-Pleistocene glacial outwash substrate by spring sapping Uchupi and Oldale, 1994. The channel-fill sequences are comprised of a transgressive systems tract composed of a consistent sequence of coastal embayment and shoreline facies that have succeeded one another in response to Holocene relative sea-level rise. As relative sea-level flooded these paleo-channels, marsh environments were established in response to rising relative sea-level. With continued sea-level rise, the marsh environments migrated farther up channel. The exposed paleo-channels continued to flood, accommodating quiet water coastal embayments, likely protected from wave action by barrier beaches located more seaward. As relative sea-level rise continued, the coastline was driven landward over regions within the paleo-channels that formerly accommodated marsh and embayment sedimentation. The landward migration of the coastline was indicated by beach and barrier facies that covered the fine grained coastal embayment sediments. With further relative sea-level rise, beach and barrier settings were eroded as the shoreface migrated farther landward and nearshore marine deposition by wave and tidal flows ensued. Sedimentary environments similar to those recorded in the channels are found in modern coastal embayments on the south shore of Cape Cod. The second channel-fill type, which forms part of the southern and western portion of the channel network is more difficult to relate to the previously described sequence. The channels that contain fill were not adequately defined in this survey but were probably incised during the late-Pleistocene in response to ice melting and retreat. The sediments that make up this channel-fill are composed mainly of late-Pleistocene glaciolacustrine silts and clays. Sediments that make up the Holocene transgressive systems tract are limited to the upper meter of this channel sequence. They are composed of two sand units that reflect Holocene beach and nearshore sedimentation. The absence of coastal embayment and other paralic facies from the systems tract suggests that these channels did not accommodate protected embayments or that these sediments were not well preserved during the submergence of this region. Changes in the channel orientation or in the rate of relative sea-level rise may have contributed to this difference in sediment fill.
by Benjamin Thomas Gutierrez.
M.S.
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Wendelberger, Kristie Susan. "Evaluating plant community response to sea level rise and anthropogenic drying: Can life stage and competitive ability be used as indicators in guiding conservation actions?" FIU Digital Commons, 2016. http://digitalcommons.fiu.edu/etd/2558.
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Increasing sea levels and anthropogenic disturbances have caused the world’s coastal vegetation to decline 25-50% in the past 50 years. Future sea level rise (SLR) rates are expected to increase, further threatening coastal habitats. In combination with SLR, the Everglades ecosystem has undergone large-scale drainage and restoration changing Florida’s coastal vegetation. Everglades National Park (ENP) has 21 coastal plant species threatened by SLR. My dissertation focuses on three aspects of coastal plant community change related to SLR and dehydration. 1) I assessed the extent and direction coastal communities—three harboring rare plant species—shifted from 1978 to 2011. I created a classified vegetation map and compared it to a 1978 map. I hypothesized coastal communities transitioned from less salt- and inundation-tolerant to more salt- and inundation-tolerant communities. I found communities shifted as hypothesized, suggesting the site became saltier and wetter. Additionally, all three communities harboring rare plants shrunk in size. 2) I evaluated invading halophyte (salt-tolerant) plant influence on soil salinity via a replacement series greenhouse experiment. I used two halophytes and two glycophytes (non-salt-tolerant) to look at soil salinity over time under 26 and 38‰ groundwater. I hypothesized that halophytes increase soil salinity as compared to glycophytes through continued transpiration during dry, highly saline periods. My results supported halophytic influence on soil salinity; however, not from higher transpiration rates. Osmotic or ionic stress likely decreased glycophytic biomass resulting in less overall plant transpiration. 3) I assessed the best plant life-stage to use for on-the-ground plot-based community change monitoring. I tested the effects of increasing salinity (0, 5, 15, 30, and 45‰) on seed germination and seedling establishment of five coastal species, and compared my results to salinity effects on one-year olds and adults of the same species. I hypothesized that seedling establishment was the most vulnerable life-stage to salt stress. The results supported my hypothesis; seedling establishment is the life-stage best monitored for community change. Additionally, I determined the federally endangered plant Chromolaena frustrata’s salinity tolerance. The species was sensitive to salinity >5‰ at all developmental stages suggesting C. frustrata is highly threatened by SLR.
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Mhlanga, Musa. "Magmatic-petrogenetic & structural relationships of the Peninsula Granite of the Cape Granite Suite (CGS) with the Malmesbury Group, Sea Point contact, Saldania Belt, South Africa." University of the Western Cape, 2020. http://hdl.handle.net/11394/8034.
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>Magister Scientiae - MScThe Sea Point contact, Cape Town, South Africa, exposes the contact between the Neoproterozoic Malmesbury Group metasedimentary rocks of the Pan-African Saldania belt and the intrusive S-type Peninsula Granite of the Neoproterozoic-Paleozoic Cape Granite Suite (CGS). The exposure outcrops over an area of approximately 170 m × 60 m with the northern end of the exposure being characterized by the country rock–microgranite intrusive contact. Heading further south, the outcrop transitions to the main contact zone, which is a predominantly gradational zone marked by sheets of compositionally variable granitic injections (collectively referred to as hybrid granite phases) concordant to the country rock structure, before reaching the main pluton area comprising the voluminous coarse-grained porphyritic granite. Using a combined study incorporating field, structural, geochemical, isotopic and U-Pb geochronological data, the intrusive contact is investigated to determine the construction history of the pluton and delineate possible emplacement mechanisms. The granitic phases, which vary from fine-grained leucocratic, medium-grained porphyritic to coarse-grained porphyritic, are peraluminous, magnesian to ferroan, and alkali-calcic. Based on the linear trends between the whole-rock major and trace element content of the granites vs. maficity (molar Fe + Mg), their initial Sr ratios and εNd(t) values, the granites of the study area are consistent with the currently proposed petrogenetic model for the CGS (e.g. Stevens et al., 2007; Villaros et al., 2009a; Harris & Vogeli, 2010); i.e., they are crustally derived and their chemical variability is controlled primarily by peritectic assemblage entrainment. The fractional crystallization of K-feldspar is identified as the primary mechanism for the local geochemical variability of the granites. The fractionation of K-feldspar as a mechanism of variability was evaluated using binary log-log diagrams of Ba, Sr and Eu and is interpreted to have taken place at levels close to the emplacement site after source entrainment processes. Although there is outcrop evidence, particularly in the main contact zone, to suggest that local assimilation and filter pressing took place, this was not reflected by the whole-rock and isotope geochemistry of the granites. This suggests that these processes are very localized and will need further rigorous testing to ascertain the extent to which they caused variability. Outcrop evidence for assimilation includes gradational country rock-granite contacts and the ductile behaviour of the country rock, whereas the occurrence of K-feldspar megacrysts embedded in the country rock at the main contact zone suggests melt accumulation and escape consistent with the filter pressing mechanism. In the case of the latter, the melt fraction of the granite was easily mobilized and driven out compared to the crystal fraction (K-feldspars) during the emplacement of the granites. Field relationships and the structural interpretation of the Malmesbury Group country rocks and the granites reveal that: (1) the various granites are late syn-tectonic and (2) were emplaced as incrementally assembled, repeated pulses of inclined granitic sheets more or less normal (i.e. at high angles) to the regional NE-SW shortening (D1) of the Malmesbury forearc during the Saldanian orogeny. Given the lack of a controlling shear zone in facilitating granite emplacement in the study area, the pre-existing planar anisotropies (bedding planes and foliations) in the country rock provided preferential pathways for magma emplacement and propagation during deformation. This implies that the tensile strength normal and parallel to the bedding and foliation anisotropy of the country rock was larger than the regional differential stress (σ1 – σ3, with σ1 ≥ σ2 ≥ σ3), allowing for magma emplacement relative to shortening. Sheet propagation is interpreted to have occurred through the balance of the following conditions: (1) density contrasts between host rocks and magmas, (2) the pressure differential along the subvertical fractures/sheets, and (3) the melt pressure equalling the lithostatic pressure to keep the magma pathways open and being sufficiently high such that it exceeds the sum of σ1 and the tensile strength of the rock parallel to σ1. The crystallization ages of the dated granite samples are identical within error and vary between 538.7 ± 3.6 Ma and 542.7 ± 2.9 Ma. They, therefore, cannot prove which granite phase intruded first and which one proceeded and so forth. Field relationships, however, suggests that the microgranites were first to intrude given their fine-grained nature and the localized chilled contacts they show with the country rock. The various coarser-grained and porphyritic phases were next to intrude, with their coarse grain-sizes and lack of chilled margins with the country rock suggesting that the time interval between their successive emplacements was not too long; this prevented the country rock from completely cooling down between each magma batch. Magma stoping and the ductile flow of the host material (owing to highly viscous magma flow) to accommodate granite emplacement are interpreted to be secondary emplacement processes.
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Schäfer, Jean Stewart. "An investigation of how visual arts can be used to teach mathematical concepts of space and shape in Grade R." Thesis, Rhodes University, 2011. http://hdl.handle.net/10962/d1003514.
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The impetus for this study came from the findings of an evaluation of a Maths and Science through Arts and Culture (MStAC) Curriculum Intervention undertaken with Grade R teachers registered for a BEd(in-service) qualification at Rhodes University, South Africa. The intervention aimed to enrich Grade R teachers’ teaching of mathematics. Post-intervention classroom observations showed that, in spite of the intervention, teachers’ classroom practices did not change, and they were not using visual arts to teach mathematical concepts. This, together with the lack of research in the field of mathematics in early childhood, particularly in South Africa, motivated this research, a case study, which investigates how visual arts can be used to teach space and shape conceptualization in Grade R. I designed a research intervention underpinned by a constructivist model of teacher professional development located in reflective practice (Borko & Putman, 1995; Zeichner & Liston, 1996; Wilmot, 2005). Guided by Stacey’s (2009) notion of an emergent curriculum, I designed a three phase research intervention which involved selected Grade R teachers undertaking classroom-based research. Phase I built awareness around the notion of creativity; Phase II focused on making meaning of children’s behaviour and interests; and Phase III applied the knowledge and ideas from the Phases I and II to the teaching of space and shape. As an interpretive research study, it closely examines the participating teachers’ perceptions, experiences and reflections which were articulated in reflective reports and assignments. Following action research processes, the participant teachers engaged in the process of an emergent curriculum. They observed the behaviour interests of Grade R children, interpreted and made meaning of the evident behaviours, made decisions regarding extension activities, and planned accordingly. The findings of the study illuminate a model of teacher professional development that can support and enhance teachers’ practice. Understanding the notion of creativity and the ability to create a classroom conducive to creativity, are necessary components for teaching space and shape through visual arts activities. An emergent curriculum approach is proposed as an appropriate pedagogy for teaching children about space and shape through visual arts activities.
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Seger, Johanna. "Coagency of humans and artificial intelligence in sea rescue environments : A closer look at where artificial intelligence can help humans maintain and improve situational awareness in search and rescue operations." Thesis, Linköpings universitet, Institutionen för datavetenskap, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-157439.
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This paper aims to answer the question of how artificial intelligence could help humans maintain and/or improve situational awareness in search and rescue operations at sea, as well as where in such processes artificial intelligence could be incorporated to most efficiently compensate for human vulnerabilities and support human strengths. In order to answer this, a joint cognitive system perspective has been adopted whilst joining in search and rescue practice operations. These operations have been observed and persons participating in them have been interviewed, in order to gather insights about the process and the persons conducting it. The results from these insights coupled with experience with artificial intelligence and automation, show that artificial intelligence could help improve and/or maintain situational awareness by adopting functions which take up unnecessary time from man. According to the joint cognitive system view, these functions should never be solely performed by artificial intelligence however, but in coagency with man; allocated functions should overlap between man and machine. Suggestions have been given regarding which functions in particular an artificial intelligent agent could perform in terms of search and rescue and where these functions occur in the process. None of these suggestions are without man involvement, as they should not be. To summarise, these suggestions include; a UAV equipped with an infrared camera to search large areas quickly, a decision support system equipped with image recognition to analyse images gathered from the UAV, as well as a communication tool which allows for shared search patterns and hotspots between search and rescue units.WARA-PS
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Stechova, Katerina. "How to best 'sell' the 'best-seller' clause? : a review on whether the contract adjustment mechanism proposed by the EU draft Digital Single Market Directive can secure fair (additional) remuneration for authors and performers." Thesis, Queen Mary, University of London, 2018. http://qmro.qmul.ac.uk/xmlui/handle/123456789/42530.
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The current - and very relevant - debate about the way authors and performers lose control over exploitation, and more importantly, revenue generated through use of their works and performances in the digital world somewhat overshadows the fact that there are existing scenarios arising from the normal course of dealings in such works where the same occurs and were remedy of any such "injustice" has not been fully enshrined in law. A right to additional fair remuneration is a concept recognised to various degrees in some Member States of the EU but not all, scaling from (seemingly) zero in the UK to quite an elaborate regulation in Germany. Where they are recognised, application and enforcement of relevant provisions also vary. The EU sought to harmonise the issue of author's and performer's access to fair share of revenue generated from exploitation of their work or performance (for normal dealings and in digital spheres of copyright exploitation) in its new draft Directive. The Proposal for a Directive on Copyright in the Digital Single Market published in September 2016 dedicates its Chapter 3 of Title IV to Fair remuneration in contracts of authors and performers; contract adjustment mechanism introduced in Article 15 attempts to tackle the issue by proposing a statutory right to additional remuneration being introduced throughout the EU Member States. Or, was the aim of this provision originally even broader? In this work, three main areas are addressed: (i) the background and justification of inclusion of such provisions into the Draft DSM Directive; (ii) current applicable law in Germany, Czech Republic and the UK; three countries each representing different historical and doctrinal approach to copyright law and thus providing unique benchmarks for the analysis, (iii) reconciliation of the first two parts: analysing what - if any - change in the national legislation would be needed for the three Member States to transpose the provision into the national laws. By way of conclusion, recommendations to amend Article 15 of the draft Directive is based on the analysis made in the third part.
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Jonsson, Estrid, and Sara Fredrikson. "An Investigation of How Well Random Forest Regression Can Predict Demand : Is Random Forest Regression better at predicting the sell-through of close to date products at different discount levels than a basic linear model?" Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-302025.
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Allt eftersom klimatkrisen fortskrider ökar engagemanget kring hållbarhet inom företag. Växthusgaser är ett av de största problemen och matsvinn har därför fått mycket uppmärksamhet sedan det utnämndes till den tredje största bidragaren till de globala utsläppen. För att minska sitt bidrag rabatterar många matbutiker produkter med kort bästföredatum, vilket kommit att kräva en förståelse för hur priskänslig efterfrågan på denna typ av produkt är. Prisoptimering görs vanligtvis med så kallade Generalized Linear Models men då efterfrågan är ett komplext koncept har maskininl ärningsmetoder börjat utmana de traditionella modellerna. En sådan metod är Random Forest Regression, och syftet med uppsatsen är att utreda ifall modellen är bättre på att estimera efterfrågan baserat på rabattnivå än en klassisk linjär modell. Vidare utreds det ifall ett tydligt linjärt samband existerar mellan rabattnivå och efterfrågan, samt ifall detta beror av produkttyp. Resultaten visar på att Random Forest tar bättre hänsyn till det komplexa samband som visade sig finnas, och i detta specifika fall presterar bättre. Vidare visade resultaten att det sammantaget inte finns något linjärt samband, men att vissa produktkategorier uppvisar svag linjäritet.As the climate crisis continues to evolve many companies focus their development on becoming more sustainable. With greenhouse gases being highlighted as the main problem, food waste has obtained a great deal of attention after being named the third largest contributor to global emissions. One way retailers have attempted to improve is through offering close-to-date produce at discount, hence decreasing levels of food being thrown away. To minimize waste the level of discount must be optimized, and as the products can be seen as flawed the known price-to-demand relation of the products may be insufficient. The optimization process historically involves generalized linear regression models, however demand is a complex concept influenced by many factors. This report investigates whether a Machine Learning model, Random Forest Regression, is better at estimating the demand of close-to-date products at different discount levels than a basic linear regression model. The discussion also includes an analysis on whether discounts always increase the will to buy and whether this depends on product type. The results show that Random Forest to a greater extent considers the many factors influencing demand and is superior as a predictor in this case. Furthermore it was concluded that there is generally not a clear linear relation however this does depend on product type as certain categories showed some linearity.
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Faasen, Petronella. "An Assessment of Accommodation Strategies for Coastal Adaptation in Cape Town, South Africa, in Response to Climate Change." Thesis, Stellenbosch : Stellenbosch University, 2014. http://hdl.handle.net/10019.1/86665.
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Thesis (MScEng)--Stellenbosch University, 2014.ENGLISH ABSTRACT: As the world finds itself increasingly unable to avoid the negative impacts of the physical phenomena associated with climate change, adaptation to climate change has been brought to the forefront of the international agenda. The range of adaptation technologies available can be categorized into three basic strategies (IPCC, 1990): Protection, (managed) Retreat, or Accommodation. The practice of adapting existing developments and infrastructure in the coastal zone by the process of accommodation has not yet seen wide implementation as a formalised adaptation strategy. In order for a community to accept and successfully implement accommodation strategies, all community stakeholders are required to accept and live with a certain level of managed risk, and to also rethink the concept of failure. As a result, accommodation practices implemented globally have been closely related to fields such as risk - and disaster management. Structural innovations in the field of accommodation measures include advanced technologies to elevate existing buildings safely above flood levels, and even “amphibious” houses. In Cape Town, South Africa, the choice between protection, retreat or accommodation as an adaptation measure remains complex. Not much discussion has yet been generated concerning accommodation measures that could be implemented to reduce the risk to existing properties that are already inappropriately located in the risk zone (e.g. seaward of the coastal hazard line), by accommodating the dynamic coastal processes taking place. Accommodation has been found to be most feasible in Cape Town at case study sites with a stable, non- or slowly eroding shoreline, which are also subject to flooding. The elevation of buildings and the alteration of buildings for flood-proofing, in unison with proactive risk and disaster management, could be implemented to accommodate the impacts of flooding on affected infrastructure. Located on Cape Town’s Atlantic Seaboard, Bakoven serves as a case study sample of such a site where an accommodation-based adaptation solution could be feasible. Both global and regional downscaled climate models have been found to deliver a large range of future climate conditions. Assuming best estimate future predictions, Bakoven properties have been found vulnerable to extreme flooding during both status quo and future extreme events. Environmental conditions at Bakoven are favourable for the construction of piled foundations. Stringent environmental and heritage constraints imposed by local government would, however, render accommodation strategies unviable. It is recommended that government at all levels be willing to adopt a more flexible approach to governing coastal areas, to ensure that the regulations they impose remain as dynamic as the environments which they govern. The viability and possible benefits of accommodation measures, rather than protection or retreat approaches should be carefully considered on an individual case-by-case basis, in unison with the local community.
AFRIKAANSE OPSOMMING: Wêreldwyd is gemeenskappe besig om toenemend te ervaar dat hul nie die nadelige gevolge van klimaatsverandering kan vryspring nie. Juis daarom, is aanpassing tot klimaatsverandering noodsaaklik. Die verskeidenheid van beskikbare benaderinge tot klimaatsverandering aanpassing kan in drie hoof kategorieë ingedeel word, volgens die IPCC (1990): Beskerming, (stelselmatige) Retireer of Akkomodasie. Die aanpassing van bestaande infrastruktuur d.m.v. akkomodasie is nog nie wyd geïmplementeer as ‘n amptelike aanpassings strategie nie. Ten einde die sukses van ‘n akkommodasie strategie te verseker, sal gemeenskappe genoodsaak wees om ‘n sekere vlak van residuele risiko te aanvaar en die konsep van die ‘faling’ te herdefinieer. Akkommodasie oplossings wêreldwyd is daarom nouliks verwant aan risiko- en rampsbestuur. Innovasies in die struktuurindustrie om die risiko van klimaatsverandering te akkommodeer, sluit onder andere in die fisiese oplig van geboue na ‘n hoër, veilige vlak, en ook die bou van sogenaamde “amfibiese” huise. In Kaapstad is die bepaling van die mees gepaste en voordelige aanpassings oplossing, net soos in die res van die wêreld, kompleks. Die moontlikheid van die gebruik van akkommodasie benaderinge en tegnologieë, eerder as beskermingsstrategieë, is nog nie welbekend of algemeen geïmplementeer nie. Daar bestaan wel ‘n geleentheid om hierdie tegnologieë toe te pas in die geval van bestaande strukture wat seewaarts van die dinamiese kusproses lyn, geleë is. Hierdie studie het bevind dat akkommodasie oplossings moontlik suksesvol kan wees by spesifieke gevallestudies langs Kaapstad se kuslyn waar die kuslyn grootendeels stabiel is. Die oplig en verandering van geboue om vloedbestand te wees, tesame met proaktiewe risiko- en rampsbestuur maatreëls, word by sommige van hierdie gevallestudies aanbeveel om die impak van klimaatsverandering te akkomodeer. Bakoven, ‘n klein gemeenskapsbuurt op Kaapstad se kuslyn, is ‘n voorbeeld van ‘n geval waar ‘n akkommodasie oplossing moontlik goed kan werk. Globale klimaatsmodelle lewer ‘n wye reeks van toekomstige klimaatsvoorspellings vir die jaar 2063. Tydens die toets van die mees waarskynlike toekomstige klimaats-scenario, is bevind dat Bakoven kwesbaar is vir die verwagte vloeding a.g.v. seevlakstyging verwag teen 2063. Daar is ook bevind dat selfs tydens huidige storms, sommige strukture aan Bakoven se kus kwesbaar is. Die omgewingstoestande by Bakoven word beskou as voordelig vir die konstruksie van heipale as fondasies om die geboue hoër op te lig. As gevolg van streng munisipale regulasies met omgewings- en geskiedkundige bewaring as doel, is hierdie opsie egter nie moontlik nie. Dit word aanbeveel dat die regulasies wat deur regeringsamptenare daargestel word, aanpasbaar genoeg moet wees om die veranderende kusomgewing in ag te neem. Die moontlikheid en volhoubaarheid van ‘n akkommodasie oplossing, eerder as ‘n beskermings- of opgee benaderinge, moet deeglik ondersoek word vir elke ‘n individuele geval, in samewerking met die betrokke gemeenskap.
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Bouhier, Nicolas. "Etude de l'impact des icebergs Antarctiques sur l'Océan Austral." Thesis, Brest, 2017. http://www.theses.fr/2017BRES0143/document.
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La calotte polaire Antarctique conditionne un flux d’eau douce dans l’océan Austral par deux voies d’égale importance : une injection immédiate et localisée par fonte des plateformes glaciaires, et une injection « offshore » et différée par production (« vêlage ») puis fonte d’icebergs. On estime ainsi que les icebergs, en fondant, pourraient modifier les caractéristiques hydrologiques et biogéochimiques de la colonne d’eau. Les modèles numériques visant à estimer cet impact présentent des résultats contrastés. Ils sont limités dans leurs stratégies de représentations des icebergs, notamment parce que les connaissances sur la distribution spatiale et de taille des icebergs ou encore leurs mécanismes de perte de masse sont réduites. Une méthode récente exploitant des mesures par altimétrie satellitaire a permis la création d’une base de données cartographiant la distribution des icebergs Antarctiques avec une couverture spatiale et temporelle inédite. Notre analyse conjointe entre ces données et des champs de concentration en glace de mer met en lumière le transport d’eau douce injecté par les icebergs et son impact sur la banquise. On analyse également les liens entre icebergs de différentes tailles : les gros peuvent être vus comme des réservoirs de volume de glace, qu’ils diffusent dans tout l’océan en se fragmentant en petits icebergs de différentes tailles. On étudie alors l’évolution de deux icebergs géants, on propose une première paramétrisation du phénomène de fracturation et analyse la distribution de taille résultante. Ces résultats peuvent permettre une représentation plus réaliste du flux d'eau douce conditionné par les icebergs dans les modèlesThe Antarctic polar ice cap constrains a freshwater flaux into the Austral Ocean through two equally important pathways : a localized and immediate injection through the melting of ice-shelves bases, and a delayed offshore injection through the calving and subsequent melt of icebergs. Some studies reckon that melting icebergs have the capacity to alter the hydrological and biogeo-chemical characteristics of the water column. The numerical models trying to evaluate this impact have shown contrasting results. Yet, they might suffer from a poor representation of the icebergs, namely due to our limited knowledge on both the spatial and size distributions of the icebergs, or even the processes involved in their mass loss. A new method using satellite altimetry measurements has lead to the creation of a database mapping Antarctic icebergs distribution with an unprecedented spatial and temporal coverage. Our joint analysis between these data and sea ice concentration fields highlights a possible transport of the freshwater injected by an iceberg and its impacts on sea ice.We also analyze the links between icebergs of different sizes : the large ones can be seen as ice buffers that diffuse across the whole ocean when breaking into small fragments of various sizes. We finally study the evolution of two giant icebergs, suggest the first parametrization of the fragmentation process and analyze the subsequent size distribution of the fragments. These results can be valuable to account in a more realistic way the fresh water flux constrained by icebergs in models
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Bri, Molinero Diana. "ESTUDIO DEL EFECTO DE FACTORES EXTERNOS SOBRE LAS REDES WLAN Y DISEÑO DE UN ALGORITMO COGNITIVO ENERGÉTICAMENTE EFICIENTE." Doctoral thesis, Universitat Politècnica de València, 2015. http://hdl.handle.net/10251/53450.
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[EN] Nowadays there are many works which analyze and seek to improve the performance of Wireless Local Area Networks (WLANs) from different perspectives. A great deal of them is focused on design aspects, such as frequency distribution or channel assignment. Therefore, as these features have already been widely studied, my efforts have been directed to study other conditions that also could affect their performance and that have not been analyzed in depth yet. The main goal of this Ph.D. dissertation has been to perform a detailed study that researches the weather's impact on the performance of WLANs IEEE 802.11b/g. Two different WLAN scenarios have been analyzed to validate the results and to find precise relations. From conclusions of these previous analysis, the second objective has been to design a cognitive protocol that based on weather conditions and network performance parameters, allows networks to adjust their transmission features in order to overcome such impact.
In order to conduct this study, firstly it was necessary to study which statistical methods could be used to extract the level of correlation between performance parameters of networks and weather conditions running at the same time. Secondly, I had to know which performance parameters the outdoor WLAN of Universitat Politècnica de València (UPV) could provide, and select them according to my objective. Then, I defined the period of time in which these parameters were gathered periodically. The next step was to select and collect the weather conditions from a close weather station during the same period of time. Finally, I had to perform a detailed pre-processing to put all of the volume of data in order and data were statistically analyzed. Results were successful; however there were several problems due to the variability derived from a real WLAN scenario. Therefore, an experimental setup was required in order to check the obtained results. It entailed to design and to develop an outdoor point-to-multipoint IEEE 802.11b/g link and to analyze again the weather's impact. Multiple points were considered in order to take into account different distances in the performed evaluation and to examine the behavior of different modulation schemes working under the same weather conditions. From these results, a cognitive algorithm was designed in order to reduce the weather's impact on IEEE 802.11b/g networks. One key aspect was to ensure it was energy efficient. This protocol was simulated and the obtained results were satisfactory in terms of both energy efficiency and network performance.
To conclude, other external factor to WLANs studied in this Ph.D thesis has been the specific absorption rate. It deals with a current public health worry because it is used to measure the body tissue exposure to electromagnetic fields. Obviously, signal absorption by human bodies affects to the performance of WLANs and so, this parameter should be also taken into account when deploying efficient networks. For this reason, this study has been also included in this thesis.[ES] Hoy en día existen muchos trabajos que analizan e intentan mejorar el rendimiento de las redes de área local inalámbricas desde diferentes perspectivas. Gran parte de estos trabajos se centran en aspectos de diseño, como son la distribución de frecuencias o la asignación de canales. Por lo tanto, como estos aspectos ya han sido ampliamente estudiados, los esfuerzos de esta tesis se han dirigido a estudiar otros factores que también podrían afectar a su rendimiento y que no han sido analizadas en profundidad todavía. El objetivo principal de esta tesis doctoral ha sido realizar un estudio detallado que analice el impacto de las condiciones meteorológicas sobre el rendimiento de las redes IEEE 802.11b/g. Para realizar este estudio, se han analizado dos escenarios reales con el fin de verificar los resultados y encontrar relaciones precisas. A partir de las conclusiones de estos análisis previos, el segundo objetivo ha sido diseñar un algoritmo cognitivo que, en base a las condiciones meteorológicas y a los parámetros de rendimiento de red, permita a las redes ajustar sus características de transmisión con el fin de superar tal impacto. Con el fin de llevar a cabo este estudio, primero fue necesario estudiar qué métodos estadísticos podían ser utilizados para extraer el nivel de correlación entre los parámetros de rendimiento de las redes y las condiciones meteorológicas del entorno. En segundo lugar, se tuvo que analizar qué parámetros de rendimiento de red se podían extraer de la red exterior de la UPV y seleccionarlos de acuerdo con el objetivo perseguido. A continuación, se definió el periodo de tiempo durante el cual se almacenarían los parámetros seleccionados de forma periódica. El siguiente paso fue seleccionar y almacenar las condiciones meteorológicas de una estación cercana durante el mismo periodo de tiempo. Finalmente, se realizó un preprocesado detallado con el fin de poner en orden todo el volumen de datos y se analizaron estadísticamente. Los resultados fueron exitosos, sin embargo aparecieron varios problemas por el hecho de estudiar una red real muy variable. Por lo tanto, se tuvo que desarrollar un escenario experimental con el fin de verificar los resultados. Para ello se diseñó y desarrolló un enlace exterior IEEE 802.11b/g punto a multipunto, y se analizó de nuevo el impacto de las condiciones meteorológicas. Se consideró un enlace multipunto para analizar también cómo influía el impacto del tiempo según la distancia y los diferentes esquemas de modulación. A partir de los resultados, se diseñó un algoritmo cognitivo energéticamente eficiente con el fin de reducir el impacto de los fenómenos meteorológicos en las redes IEEE 802.11b/g. Dicho algoritmo ha sido simulado y los resultados obtenidos han sido satisfactorios, tanto en términos de eficiencia energética como de rendimiento de la red. Para concluir, otro factor externo que se ha estudiado en esta tesis ha sido la tasa de absorción específica. Este parámetro está relacionado con una de las grandes preocupaciones actuales en cuanto a salud pública, ya que se utiliza para medir la exposición de los tejidos del cuerpo humano a los campos electromagnéticos. Obviamente, la absorción de señal por parte del cuerpo humano afecta a las redes y, por lo tanto, este parámetro se debería tener en cuenta a la hora de diseñar redes eficientes. Por esta razón se ha incluido en esta tesis doctoral.
[CAT] Actualment hi ha molts treballs que analitzen i intenten millorar el rendiment de les xarxes d'àrea local sense fils des de diferents perspectives. Gran part d'aquests treballs es focalitzen en aspectes de disseny, com són la distribució de freqüències o l'assignació de canals. Per tant, com aquests aspectes ja han sigut àmpliament estudiats, els esforços d'aquesta tesi doctoral s'han dirigit a estudiar altres factors que també podrien afectar al seu rendiment i que encara no han sigut analitzats amb profunditat. L'objectiu principal d'aquesta tesi doctoral ha sigut realitzar un estudi minuciós per analitzar l'impacte de les condicions meteorològiques sobre el rendiment de les xarxes IEEE 802.11b/g. Per a realitzar aquest estudi s'han analitzat dos escenaris reals per tal de verificar els resultats i trobar relacions precises. A partir de les conclusions d'aquests anàlisis previ, el següent objectiu ha sigut dissenyar un algoritme cognitiu que, en base a les condicions meteorològiques i als paràmetres de rendiment de la xarxa, permeti a les xarxes ajustar les seues característiques de transmissió per tal de superar tal impacte. Per tal de dur a terme aquest estudi, primer va ser necessari estudiar quins mètodes estadístics podien ser utilitzats per extraure el nivell de correlació entre els paràmetres de rendiment de les xarxes i les condicions meteorològiques de l'entorn. En segon lloc, es va haver d'analitzar quins paràmetres de rendiment es podien extraure de la xarxa exterior de la UPV i es van seleccionar d'acord a l'objectiu plantejat. A continuació, es va definir el període temporal al llarg del qual s'emmagatzemarien els paràmetres seleccionats de manera periòdica. El següent pas va ser seleccionar i emmagatzemar les condicions meteorològiques d'una estació propera durant el mateix període de temps. Finalment, es va realitzar un preprocessat per tal de posar en ordre tot el volum de dades i es van analitzar estadísticament. Els resultats van ser exitosos, però van aparèixer diversos problemes pel fet d'estudiar una xarxa real molt variable. Per tant, es va haver de desenvolupar un escenari experimental amb l'objectiu de verificar els resultats. Per aquesta raó es va dissenyar i implementar un enllaç exterior IEEE 802.11b/g punt a multipunt, i es va analitzar de nou l'impacte de les condicions meteorològiques. Es va considerar un enllaç multipunt per tal de d'analitzar també com influïa el impacte del temps segons la distància i els diferents esquemes de modulació. A partir d'aquests resultats, es va dissenyar un algoritme cognitiu energèticament eficient per tal de reduir l'impacte dels fenòmens meteorològics sobre les xarxes IEEE 802.11b/g. Aquest algoritme va ser simulat i els resultats obtinguts van ser satisfactoris, tant en termes d'eficiència energètica com de rendiment de la xarxa. va comprovar que la proposta aporta millores. Per concloure, un altre factor extern que s'ha estudiat en aquesta tesi doctoral ha sigut la taxa d'absorció específica. Aquest paràmetre està relacionat amb una de les preocupacions actuals pel que fa a la salut pública, ja que s'utilitza per a mesurar l'exposició dels teixits del cos humà als camps electromagnètics. Òbviament, aquesta absorció de la senyal afecta el rendiment de les xarxes i, per això, aquest paràmetre s'hauria de tenir en compte a l'hora d'implementar futures xarxes sense fils eficients. Per aquesta raó s'ha inclòs en aquesta tesi doctoral.
Bri Molinero, D. (2015). ESTUDIO DEL EFECTO DE FACTORES EXTERNOS SOBRE LAS REDES WLAN Y DISEÑO DE UN ALGORITMO COGNITIVO ENERGÉTICAMENTE EFICIENTE [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/53450
TESIS
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Fanti, Laura. "La fonction des récipients céramiques dans les sociétés du Néolitique moyen B (4500-4000 cal BC) en Sardaigne centre-occidentale (Italie) : Indices fonctionnels, économiques, interculturels à partir de l’analyse des caractéristiques morphométriques, des résidus organiques et des traces d’usure des poteries." Thesis, Nice, 2015. http://www.theses.fr/2015NICE2024.
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La Sardaigne, en raison de sa position géographique au cœur de la Méditerranée occidentale, constitue une zone clé pour la compréhension de la diffusion du Néolithique dans le domaine nord-tyrrhénien. La deuxième moitié du Ve millénaire cal BC marque l’essor et l’aboutissement du processus de diffusion de l’économie néolithique dans l’île, sous l’égide des groupes humains « San Ciriaco ». Des fouilles récentes dans la Sardaigne centre-occidentale, zone cruciale pour cette entité culturelle régionale, ont décelé des contextes inédits dont l’étude est fondamentale pour la connaissance de ces sociétés. Cette thèse se propose d’explorer le rôle des poteries dans les systèmes techniques et les comportements symboliques des groupes humains San Ciriaco en Sardaigne centre-occidentale, afin d’obtenir des indices économiques sur les stratégies de gestion des ressources et sur les modes de vie de ces populations. L’approche interdisciplinaire suivie combine l’analyse morphométrique des récipients, l’observation des traces d’usure et l’analyse chimique des résidus organiques (en CPG et CPG/SM) piégés dans la matrice céramique. Les résultats révèlent une structuration des assemblages céramiques en plusieurs gammes fonctionnelles, variablement représentées sur des sites à destination différente (habitat, sépultures, « dépôts » de vases). Des comportements techniques et symboliques liés à la gestion des récipients tout au long de leur cycle d’utilisation sont mis en lumière. Ces résultats offrent une première contribution à la plus large problématique de l’évolution de la fonction des poteries, tout au long du Néolithique, au sein du domaine méditerranéen occidental.zone cruciale pour cette entité culturelle régionale originale, ont décelé des contextes inédits dont l’étude s’avère être fondamentale pour la connaissance de ces sociétés. Cette thèse se propose d’explorer le rôle des poteries dans les systèmes techniques et les comportements symboliques des groupes humains San Ciriaco en Sardaigne centre-occidentale, afin d’obtenir des indices économiques sur les stratégies de gestion des ressources et sur les modes de vie de ces populations. L’approche interdisciplinaire suivie combine l’analyse morphométrique des récipients, l’observation des traces d’usure et l’analyse chimique des résidus organiques (en chromatographie en phase gazeuse et chromatographie en phase gazeuse couplée à la spectrométrie de masse), piégés dans la matrice céramique. Les résultats obtenus révèlent une structuration des assemblages céramiques en plusieurs gammes fonctionnelles distinctes et variablement représentées sur des sites à destination fonctionnelle différente (habitat, sépultures, « dépôts » de vases). Des comportements techniques et symboliques liés à la gestion des récipients tout au long de leur cycle d’utilisation sont également mis en lumière. Ces résultats offrent une première contribution à la plus large problématique de l’évolution de la fonction des poteries, tout au long du Néolithique, au sein du domaine méditerranéen occidentalThe isle of Sardinia (Italy) is a key zone in understanding the spread and the diffusion of the Neolithic in North Tyrrhenian region, due to its position in the middle of western Mediterranean Sea. Here, the rise and culmination of Neolithic economy is carried by San Ciriaco populations in the second half of V millennium cal BC. Recent archaeological excavations in central-western Sardinia revealed new contexts the study of which is fundamental in increasing our knowledge of these Neolithic societies.The aim of this work is to investigate the role of pottery in technical systems and symbolical behaviours of San Ciriaco societies in central-western Sardinia, in order to find evidence of strategies of use and explore their way(s) of life. The interdisciplinary approach in this study combines morphometrical analysis of vessels, use-wear observation and GC / GC-MS chemical analysis of organic residues absorbed in pottery.This research revealed a structuration of pottery assemblages into several functional categories which are differently represented in sites with a different function (settlements, burials, vessels “deposits”). The results contribute to highlight technical and symbolical behaviors linked to the use of pottery during its life cycle phases. These data offer a contribution to the issue of the evolution of pottery function during the Neolithic period in Western Mediterranean
La Sardegna, in virtù della sua posizione centrale nel Mediterraneo occidentale, rappresenta una zona cruciale per la comprensione del processo di propagazione del Neolitico e della sua evoluzione nell’area nord-tirrenica. Il pieno sviluppo dell’economia neolitica nell’isola è segnato dalla formazione e diffusione di un’entità culturale regionale originale, denominata “cultura di San Ciriaco”, durante la seconda metà del V millennio cal BC (Neolitico Medio B). Alcuni recenti scavi nella Sardegna centro-occidentale, scenario fondamentale nello sviluppo di tale entità culturale, hanno portato alla luce dei contesti inediti, il cui studio si rivela essenziale per la conoscenza di queste società neolitiche.L’obiettivo di questa ricerca è specificamente quello di indagare il ruolo dei recipienti ceramici nei sistemi tecnici e nei comportamenti simbolici dei gruppi umani San Ciriaco della Sardegna centro-occidentale, nell’intento di acquisire degli indizi sulle strategie di gestione delle risorse naturali e sulle modalità di sussistenza delle popolazioni durante il Neolitico medio B.L’approccio interdisciplinare seguito associa l’analisi morfometrica dei recipienti all’osservazione delle tracce d’uso e all’analisi chimica dei residui organici assorbiti nella matrice ceramica, mediante la tecnica della gascromatografia (GC) e della gascromatografia/spettrometria di massa (GC/MS).I risultati ottenuti rivelano una strutturazione delle collezioni ceramiche in molteplici gamme funzionali distinte e variabilmente rappresentate in siti con destinazione funzionale differente (abitato, sepolture, “depositi” di recipienti). L’analisi di tali contesti ha permesso di evidenziare alcuni specifici comportamenti tecnici e simbolici legati alla gestione dei recipienti durante tutto il loro ciclo d’utilizzo.L’interpretazione storica dei dati acquisiti con questa ricerca offre un contributo alla più vasta questione dell’evoluzione della funzione dei recipienti ceramici, nel corso del Neolitico, nell’area del Mediterraneo occidentale
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Brilouet, Pierre-Etienne. "Thermodynamique et turbulence dans les épisodes de vent fort sur le Golfe du Lion." Thesis, Toulouse 3, 2017. http://www.theses.fr/2017TOU30192/document.
Full textAbstract:
En période hivernale, le golfe du Lion est sujet à des conditions de vents régionaux forts (Mistral et/ou Tramontane) qui transportent des masses d'air continentales froides et sèches au dessus de la mer. Ces événements, les Cold Air Outbreaks (CAO) , conduisent à d'intenses échanges air-mer et donc à un pompage de chaleur qui favorise la formation d'eaux denses et le déclenchement de la convection océanique profonde. La bonne représentation de ces échanges air-mer intenses dans les modèles de climat et de prévision numérique du temps reste à l'heure actuelle une problématique majeure. Elle est au cœur du projet ASICS-MED centré sur compréhension des mécanismes de formation d'eaux denses en Méditerranée et qui s'inscrit dans le cadre de la thématique " Échanges air-mer intenses " du programme HyMeX dédié à l'étude du cycle de l'eau en Méditerranée. Les processus qui s'opèrent au sein de la couche limite atmosphérique marine (CLAM) et de la couche de mélange océanique (CMO) interagissent entre eux à différentes échelles spatiales et temporelles. La compréhension de l'évolution globale de la CLAM mais également des mécanismes locaux nécessitent la prise en compte de l'ensemble des processus. L'étude présentée ici est consacrée à la structure moyenne et turbulente de la CLAM en conditions de vents forts. L'objectif est de déterminer comment l'organisation du champ turbulent est impactée lors d'épisodes de CAO et d'estimer les flux de surface associés à ces conditions de vents forts. La méthodologie adoptée est basée sur l'utilisation conjointe d'observations aéroportées collectées lors de la campagne de mesure SOP2 d'HyMeX et de simulations numériques. La campagne de mesure SOP2 d'HyMeX qui a eu lieu au cours de l'hiver 2013 dans le golfe du Lion a permis de documenter grâce à l'avion de recherche ATR42 la structure moyenne et turbulente de la CLAM lors de 11 épisodes de CAO. Une analyse spectrale s'appuyant sur un modèle analytique a été réalisé sur 181 paliers (i.e. segments de vol rectilignes et stabilisés en altitude). Les profils verticaux des échelles turbulentes caractéristiques ainsi que la forme du spectre de la vitesse verticale ont permis de mettre en évidence un allongement des structures énergétiques dans l'axe du vent moyen associé à l'organisation du champ turbulent sous la forme de rouleaux longitudinaux. Une description unidirectionnelle du champ turbulent tridimensionnel peut conduire à une représentativité limitée des structures cohérentes au sein des échantillons. Cependant, la connaissance des profils de flux sur toute l'épaisseur de la CLAM est nécessaire pour l'estimation des échanges air-mer. Une méthode de correction des flux turbulents calculés par eddy correlation a été appliqué afin de prendre en compte les erreurs systématique et aléatoire relatives à la mesure et au traitement de données. Cette correction a permis de déterminer les meilleures estimations possibles des flux extrapolés à la surface avec une marge d'incertitude pour les 11 épisodes de CAO documentés lors de la campagne SOP2 d'HyMeX. La comparaison de ces estimations aéroportées aux autres sources d'information dérivées de paramétrisations des flux a permis de mettre en évidence une sous-estimation systématique du flux de chaleur latente en conditions de vents forts. Une approche numérique a permis de compléter l'analyse de la structure moyenne et turbulente de la CLAM lors d'épisodes de CAODuring winter, local strong winds (Mistral or Tramontana) occurred in the Gulf of Lion which bring cold and dry continental air over a warmer sea. Those events, the cold air outbreaks, can lead to intense air-sea interactions which favour dense water formation and deep oceanic convection. The representation of air-sea exchanges is a fundamental aspect of of climate modelling and numerical weather forecasting. The ASICS-MED project aims to identify fine-scale processes leading to dense water formation and is a part of the "Intense air-sea exchanges" topic of the HyMeX program devoted to hydrological cycle in the Mediterranean. The processes occurring within the marine atmospheric boundary layer (MABL) and the oceanic mixing layer (ML) interact with one another at different spatial and temporal scales. Understanding the overall evolution of the MABL but also the local mechanisms requires taking into account all the processes. The study presented here is devoted to the mean and turbulent structure of the MABL under strong wind conditions. The objective is to determine how the organization of the turbulent field is impacted during CAO events and to estimate the surface fluxes associated with these strong wind conditions. The methodology adopted is based on the joint use of airborne observations collected during the HyMeX-SOP2 field campaign and numerical simulations. The HyMeX-SOP2 field campaign took place during the winter of 2013 in the Gulf of Lion. The research aircraft ATR42 was operated to document the mean and turbulent structure of the MABL during 11 CAO events. A spectral analysis based on an analytic model was carried out on 181 legs (i.e. stacked straight and level runs stabilized in altitude). The vertical profiles of the turbulent characteristic scales as well as the shape of the vertical velocity spectrum revealed an elongation of the energy structures in the mean wind direction associated with the organization of the turbulent field into longitudinal rolls. A unidirectional sampling of the three-dimensional turbulent field may lead to a limited representativeness of the coherent structures within the samples. However, knowledge of kinematic fluxes profiles over the entire thickness of the CLAM is necessary to estimate air-sea exchanges. A correction method was applied to turbulent fluxes calculated by eddy correlation in order to take into account systematic and random errors related to measurement and data processing. This correction made it possible to determine the best possible estimates of the extrapolated surface fluxes with a margin of uncertainty for the 11 CAO events documented during the HyMeX-SOP2 field campaign. The comparison of these airborne estimates with the other sources of information derived from bulk parameterizations show a systematic underestimation of the latent heat flux under strong wind conditions. A numerical approach allowed to complete the analysis of the mean and turbulent structure of the MABL during CAO events. The numerical study, based on the non-hydrostatic Meso-NH model, focuses on an episode of strong Tramontana with winds greater than 25m/s documented during the HyMeX-SOP2 field campaign. In a first step, a one-dimensional framework made it possible to understand the forcing terms necessary to reproduce in a realistic way the development of the observed MABL. This reference configuration allowed, in a second time, a Large-Eddy Simulation of the CAO event. This simulation has been validated using airborne data and has allowed to deepen the description of the turbulent field as well as the evolution of the coherent structures oriented in the axis of the mean wind
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Díaz, Caballero Elena. "Efficient analysis and design of devices in Substrate Integrated Waveguide (SIW) technology." Doctoral thesis, Universitat Politècnica de València, 2013. http://hdl.handle.net/10251/34627.
Full textAbstract:
Para abordar el análisis de estas estructuras de forma altamente eficiente, se pretenden utilizar dos enfoques distintos, que llevarían a dos técnicas distintas y eficientes, pero cada una de ellas con sus ventajas e inconvenientes respecto de la otra, que podremos concluir una vez finalizado el trabajo de investigación.
Por un lado, se pretende utilizar el Método de los Momentos, una técnica numérica que convierte las ecuaciones integrales de un problema electromagnético en un sistema linear, expandiendo la magnitud desconocida usando un conjunto de funciones con coeficientes desconocidos. Al forzar las condiciones de contorno, en este caso de potencial eléctrico, en un determinado número de puntos, se obtiene un sistema linear de ecuaciones que será resuelto numéricamente.
Por otro lado, según el segundo enfoque, pretende utilizar una expansión en modos cilíndricos del campo, tanto incidente como dispersado. Dada la geometría circular de las vías éstas pueden ser caracterizadas de forma analítica mediante espectros circulares. Posteriormente se resolverá el acoplo entre las vías mediante el método de [1] pero generalizado al caso de objetos inmersos en un medio dieléctrico infinito, y se desarrollará un nuevo método de acoplo modal entre modos cilíndricos y modos guiados proyectando las ecuaciones del acoplo modal tanto sobre modos cilíndricos como sobre modos guiados para evitar las singularidades que aparecen con el método de de [2] cuando los planos de referencia están muy próximos al objeto dispersor. Por tanto, esta técnica caracterizará las vías de forma analítica y resolverá las integrales del acoplo de modos mediante la transformada rápida de Fourier.
Para aumentar más aún la eficiencia de ambos métodos se evitará repetir los cálculos para cada punto en frecuencia, y se implementará la técnica de barrido rápido en frecuencia similar descrita en [3], adaptándola al caso particular de cada método de análisis, aunque se prevé que quizá dicho procedimiento sea más difícil de implementar en el segundo método.
Se espera que ambas técnicas puedan proporcionar unos tiempos de computación inferiores a los del software comercial de análisis electromagnético más habitual (i.e. HFSS), y también inferiores a otros métodos de análisis recientemente aparecidos en la bibliografía técnica ([4],[5],[6]). En concreto, se espera que los tiempos de computación para barrido discreto en frecuencia sea inferior con el segundo método ya que usa únicamente expresiones analíticas y transformada rápida de Fourier, pero, dado que el primer método es más susceptible de realizar barrido rápido en frecuencia, éste puede ser muy útil a la hora de realizar muchos análisis consecutivos.
Una vez se disponga de métodos eficientes para el análisis de dispositivos SIW, se abordará el diseño de varios dispositivos pasivos en esta tecnología (filtros de diferentes topologías, diplexores, multiplexores, híbridos, acopladores, etc.). Como se dispone de una vasta experiencia en el grupo de investigación en el diseño de dispositivos en guía de onda rectangular, se puede como primera aproximación realizar el diseño en guía, y luego transformar esta estructura guiada en otra en tecnología SIW mediante unas reglas empíricas que relacionan ambas tecnologías [7]. Posteriormente se debe ajustar el diseño en el dispositivo SIW ya que estas reglas empíricas no consiguen que la respuesta sea idéntica a la del dispositivo guiado original, principalmente debido al hecho de que los irises rectangulares de la guía son transformados en vías metalizadas con geometría circular, no rectangular. Para minimizar este ajuste, se diseñará el dispositivo guiado con irises con esquinas redondeadas en la cavidad (método de [8] pero con un simulador más eficiente [9]), haciendo que el radio de esas esquinas redondeadas coincida con el de las vías metalizadas que se van a utilizar en el dispositivo SIW. Esto permitirá [...] (Ver documento anexo)Díaz Caballero, E. (2013). Efficient analysis and design of devices in Substrate Integrated Waveguide (SIW) technology [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/34627
TESIS
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"Application of capillary pressures in determining the seal capacity of Eromanga Basin cap-rocks." Title page, contents and abstract only, 1992. http://web4.library.adelaide.edu.au/theses/09SM/09sms689.pdf.
Full text
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Camac, Bronwyn Anne. "An integrated geomechanical evaluation of cap and fault-seal for risking petroleum trap integrity using distinct element and boundary element numerical methods." Thesis, 2009. http://hdl.handle.net/2440/63712.
Full textAbstract:
This thesis comprises nine published papers on an integrated geomechanical evaluation of cap and fault-seal for risking petroleum trap integrity using distinct element and boundary element numerical methods. Paper 1 provides back-ground information and an introduction to the body of research presented in this thesis. In some parts of the Penola Trough, South Australia, the seal lithotype is fractured providing structural permeability and thereby compromising seal competency. This work inferred that existing geomechanical techniques, which only considered stresses on the fault plane, had limited application in the prediction of fracture generation within the country rock away from the well-bore. It also suggested that computational stress modelling techniques may provide a useful tool in this area and similar tectonic provinces.
An important stage of the modelling workflow is analysing the sensitivity of the numerical models to various input parameters. Papers 2 and 3 show that the models are particularly sensitive to fault parameters such as friction angle (o) and cohesion (C). However, fault rock properties are not well understood in petroleum exploration due to depths of investigation and the expense of acquiring core samples.
This thesis develops a new technique, using widely available dipmeter data for the entire borehole. In this, rotations in borehole breakouts caused by discontinuities, in the vertical sense, are used to give qualitative indications of fault rock behaviour (Paper 3). These observations were used to make decisions about fault rock input parameters into the numerical stress models. Paper 8 showed the results of varying fault rock stiffness moduli and fault zone width on the predicted stress within the surrounding rock mass. Where the prevailing stress conditions border between stress regimes, a new and unconventional technique whereby is used to increase confidence in understanding the stress regimes active at a particular depth and/or location (Paper 7). A comparative study of a single fault using three different methods of stress modelling, the distinct / discrete element (DEM), boundary element (BEM) and finite difference (FDM) methods (Paper 7) showed that the DEM underestimated the stress perturbation relative to the other models. Therefore where a clear variation is shown by DEM, there is increased confidence that it does exist and will be enhanced using other codes. Where there is the requirement to model multiple faults, DEM is preferred as the other methods trialled either have restrictions to the number of faults incorporated into the models (FDM) or does not account for full fault interaction and possible moment rotations between fault blocks, such as in the case of BEM.
The application of computational stress modelling offers a new workflow to fully integrate stress studies, cap-seal analysis, fault-seal analysis and structural interpretation to improve the understanding of hydrocarbon leakage risk at the prospect and play scales and was illustrated by way of multiple case study examples (Papers 4, 5, 6, 7 & 8).
The research presented in this thesis has development new concepts and additional workflows which add to the ‘tool-box’ that may be used by those researchers and consultants working in the field of petroleum geomechanics (Paper 9).Thesis (Ph.D.) -- University of Adelaide, Australian School of Petroleum, 2009