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1
Parrow, Thato Robina. "Resettlement and poverty : the plight of vulnerable groups affected by the Lesotho highlands water project : case study of phase 1B communities." Master's thesis, University of Cape Town, 2002. http://hdl.handle.net/11427/14943.
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Bibliography: leaves 86-90.Involuntary resettlement due to planned economic interventions for the purpose of economic growth, is a political and socio-economic phenomenon. It is associated with development and poverty, as it affects livelihoods of those involved. This process impacts differently on different individuals, depending on their capability to regain earning and productive bases, to access support systems, as well as to access opportunities and widen choices that sustain their lives. The study investigates the assumption that their vulnerability, ineligibility for compensation provisions and lack of specific programmes to address their needs affect their capability to adjust in new areas. In view of this, the purpose of the study is to explore the impact of resettlement on vulnerable groups (the landless, unemployable aged and disabled). The overall objective is to highlight their situation, because of a concern for their long-term welfare, possible marginalisation from mainstream development and risk of poverty. The coverage involved vulnerable groups in stage one resettlement. A stratified sampling technique was employed to select 31 respondents who represent these groups. In the study, primary and secondary data were collected by making use of In-depth interviews, focus-group discussions and content analysis of related literature. A semi-structured schedule with open-ended questions was employed to gather information that was qualitatively manipulated. The findings suggest that the resettlement process has resulted in the disruption of support systems, limited opportunities in host areas, and inadequate restorative measures to sustain livelihoods of vulnerable groups. As a result, these groups are disempowered, marginalised and excluded from mainstream social and economic development, which compounds their risk of impoverishment.
2
Sato, Chizuko. "Forced removals, land NGOs and community politics in KwaZulu-Natal, South Africa, 1953-2002." Thesis, University of Oxford, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.432141.
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Bennett, Bonita. "Temporal representation in narratives of forced removals : a narrative analysis of life story texts." Thesis, University of Cape Town, 2005. http://hdl.handle.net/11427/6716.
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In this thesis I have examined the life stories of three victims of forced removals. It is based on an understanding that there is much that we can learn from the lives of 'ordinary people' and that the oral medium is a rich source of understanding other aspects of society. Chapter 1 sketches the background of this study, and the socio-political context within which it has grown. In the main theory section (chapter 2), I provide a general overview of the tools of narrative-based discourse analysis which I have used for my work and lead into a consideration of theories of memory and time. I focus particularly on aspects of representation of time in narrative and explore the nature of traumatic memory in relation to this. In chapter four, my analysis draws attention to the different ways in which narrators make sense of the traumatic event in their lives. In fact, my analysis demonstrates that trauma shares fewer features with 'events' (as understood by Portelli, Ricouer and others), and seems to correspond more closely to an understanding of it as 'duration'. I conclude that the concept of linear time is not the organising principle in the narratives which I have examined, and that the forced removal has been a central occurrence around which the rest of life - and narrating about life is understood.
4
Hector-, Kannemeyer Renee Allison. "Current manifestation of trauma experienced during forced removals under apartheid: interviews with a former "Vlakte" inhabitant." Thesis, University of the Western Cape, 2010. http://etd.uwc.ac.za/index.php?module=etd&action=viewtitle&id=gen8Srv25Nme4_2123_1361369164.
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Much has been researched in South Africa about the trauma of losing one&rsquo
s home, one&rsquo
s community and rebuilding one&rsquo
s life in a new environment. Several books have been published tracking the lives of the forcibly removed and their responses to leaving District Six. My research focuses on a different group namely those who had been forcibly removed from the centre of Stellenbosch, called &ldquo
Die Vlakte&rdquo
during that time. Living and working with and among people who have experienced this removal, I was keen to research whether the impact of the trauma is currently
manifesting in this specific community and if so, what the symptoms would be. This qualitative inquiry focuses on one particular individual, Mr. Hilton Biscombe. I selected him because he, who experienced the removal as a teenager, spent most of his later life determinedly collecting stories and documents relating to this incident. Mr. Biscombe is also the only person of whom I am aware who responded personally through compiling a book, making a DVD, writing poetry as well as an autobiography relating to this event. My inquiry into the ways trauma manifests in a narrative, will be based on two interviews: one conducted by a white man from the University of Stellenbosch thirty years after the event
and another interview, six years later, conducted by myself.Our understanding of trauma is usually associated with a death or injury or the possibility thereof, but it could also include the victim&rsquo
s response to extreme fear, serious harm or threat to
family members. According to van der Merwe and Vienings, people also become traumatized when witnessing harm, physical violence or death or the sudden loss or destruction of a victim&rsquo
s home (van der Merwe &
Vienings, 2001). So the issue of trauma is not in question, nor the fact that forced removals cause trauma. I am exploring testimony in the form of interviews for possible current manifestations of this trauma thirty-six years down the line.
5
Kannemeyer, Renee Allison Hector. "Current manifestation of trauma experienced during forced removals under apartheid: interviews with a former “VLAKTE” inhabitant." Thesis, University of the Western Cape, 2010. http://hdl.handle.net/11394/3732.
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Magister Artium - MAMuch has been researched in South Africa about the trauma of losing one’s home, one’s community and rebuilding one’s life in a new environment. Several books have been published tracking the lives of the forcibly removed and their responses to leaving District Six. My research focuses on a different group namely those who had been forcibly removed from the centre of Stellenbosch, called “Die Vlakte” during that time.Living and working with and among people who have experienced this removal, I was keen to research whether the impact of the trauma is currently manifesting in this specific community and if so, what the symptoms would be. This qualitative inquiry focuses on one particular individual, Mr. Hilton Biscombe. I selected him because he, who experienced the removal as a teenager, spent most of his later life determinedly collecting stories and documents relating to this incident. Mr.Biscombe is also the only person of whom I am aware who responded personally through compiling a book, making a DVD, writing poetry as well as an autobiography relating to this event. My inquiry into the ways trauma manifests in a narrative, will be based on two interviews: one conducted by a white man from the University of Stellenbosch thirty years after the event; and another interview, six years later, conducted by myself.Our understanding of trauma is usually associated with a death or injury or the possibility thereof, but it could also include the victim’s response to extreme fear, serious harm or threat to family members. According to van der Merwe and Vienings, people also become traumatized when witnessing harm, physical violence or death or the sudden loss or destruction of a victim’s home (van der Merwe & Vienings, 2001).So the issue of trauma is not in question, nor the fact that forced removals cause trauma. I am exploring testimony in the form of interviews for possible current manifestations of this trauma thirty-six years down the line.
South Africa
6
Wotshela, L. E. "Homeland consolidation, resettlement and local politics in the Border and the Ciskei region of the Eastern Cape, South Africa, 1960 to 1996." Thesis, University of Oxford, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.391225.
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Bezuidenhout, G. J. W. "Land, church, forced removals and community on Klipfontein farm in the district of Alexandria, Eastern Cape c. 1872 - 1979." Thesis, Rhodes University, 2017. http://hdl.handle.net/10962/5104.
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This thesis is a case study of how church, land and dispossession of land has influenced identity formation of a coloured community in the Eastern Province, namely the Klipfontein community. Coloured history in the Eastern Province has largely been neglected. This study attempts to rectify such a lack of in-depth enquiry as it may lead to misinterpretations that may influence contemporary politics and identity formation. Through research based on primary sources, it is evident that the social landscape of Klipfontein Farm and the relationships between that community and surrounding black African and white communities have largely been shaped by the stipulations contained in the joint will of the community’s ancestors: Dirk and Sarah Janse van Rensburg. The land devolved into a trust and has been administered by trustees since the death of the first spouse in 1877. By keeping the land in a trust, it enabled the descendants to continue to live on the farm in perpetuity, without the risk of being forced off the land via financial restraints or racially-based legislation. But the usufructuaries could also never fully utilise Klipfontein as an agricultural concern due to a combination of a lack of equipment and skill, and the provisions of the will. These complications inevitably led to inter-familial disputes and tension. Before 1939 there had already been three court cases dealing with the interpretations of the Will. In that same year the Supreme Court ordered that tracts of the land, including a part of Boesmansriviermond village, be sold in order to pay off arrear rates and taxes. Although the responsibility for these sales lay with the trustees, the community has been suspicious of the usufructuaries ever since. A key element of the Klipfontein identity is their religion. The church legitimises their right to the farm - against those who wish to take that right away. Their claim to occupation is couched in scriptural discourse, viewing Klipfontein as 'their Garden of Eden' that God gave to the stamvader, Dirk Janse van Rensburg. This seemed to have been partially successful for the Klipfontein community in staving off harassment by authorities. It also caused friction between the community and the black African residents. Some usufructuaries and family members felt that such right was exclusively given to the coloured community and so they became increasingly annoyed by the black Africans who settled there. Other usufructuaries did not share this feeling. They allowed evicted black African farm labourers to settle on certain portions of Klipfontein until the late 1970s. The black African population rapidly increased due to misinformation and evictions from neighbouring farms. This only further exacerbated the inter-familial conflict between usufructuaries, flaring tensions between the black Africans and their reluctant hosts as well as animosity from the white community towards Klipfontein. In 1979, after a series of court cases, a decision was made to remove all the African settlers by force and relocate most of them to the ‘homeland’ of Ciskei. The rest, who were of ‘working-age’ were left behind in a ‘temporary emergency camp’ on the outskirts of Kenton-on-Sea. The effects of these removals still impact the relationships between the different racial groups in the area to this day.
8
Sambumbu, Sipokazi. "Social history, public history and the politics of memory in re-making 'Ndabeni'' pasts." Thesis, University of the Western Cape, 2010. http://hdl.handle.net/11394/2315.
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Kganyapa, Leonard Tsidiso. "The Struggle of the Lesotho Evangelical Church in Southern Africa (LECSA)/Paris Evangelical Missionary Society (PEMS) in Meadowlands, Soweto, in becoming a missional ecclesia in a local context." Diss., University of Pretoria, 2016. http://hdl.handle.net/2263/56958.
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The existence of the Lesotho Evangelical Church in Southern Africa (LECSA) or Paris Evangelical Missionary Society (PEMS) in the Western Areas of Johannesburg, South Western Township (Soweto) and more poignantly, Meadowlands and their forced removals experience is succinctly captured. The struggle of the LECSA/PEMS Meadowlands Parish in becoming a missional ecclesia in a sea of missional challenges in her context are vividly spelt out. They, inter alia, include constitutional matters, language policy, finances, ministerial preparation, lay-ministry development, institutionalisation of ministry, unity issues, prophetic ministry, mission and evangelism. The researcher, then, proposes an intervention – of course not a perfect one – that perhaps will galvanise the LECSA/PEMS Meadowlands Parish members to improve on what they have been doing and become a missional ecclesia in her context, Meadowlands.Dissertation (MA)--University of Pretoria, 2016.
tm2016
Science of Religion and Missiology
MA
Unrestricted
10
Kgari-Masondo, Maserole Christina. ""A superstitious respect for the soil"? : environmental history, social identity and land ownership - a case study of forced removals from Lady Selborne and their ramifications, c. 1905 to 1977 /." Thesis, Link to the online version, 2008. http://hdl.handle.net/10019.1/1215.
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BARROSO, ALEXANDRE LIMA. "EXPERIMENTAL STUDIE OF FORCES FOR WAX REMOVAL IN PIGGING OPERATIONS." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2003. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=4511@1.
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PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIROUm dos problemas encontrados na indústria do petróleo no que diz respeito a garantia de escoamento durante produção de óleo cru trata-se da deposição das frações parafínicas no interior dos tubos.Gastos significantes estão associados ao bloqueio parcial ou total das linhas de produção. O procedimento mais aplicado para remoção mecânica destes depósitos é a passagem de pigs. Uma das forças de contato que atua no pig durante o procedimento de remoção deste depósito é exercida pela camada de parafína depositada na parede do tubo. À medida que se processa a remoção mecânica e se estabelece o deslocamento do pig e da parafina removida outras forças de contato se caracterizam. O conhecimento da força necessária para quebra e remoção de um depósito específico é um ponto chave para o planejamento seguro e eficiente de uma operação de passagem de pig. Este trabalho propõe-se a estudar experimentalmente a força de contato deste depósito controlando as variáveis que influenciam esta força, analisando os resultados de acordo com os parâmetros envolvidos e os comparando com os resultados obtidos com modelos disponíveis na literatura.
Wax deposition inside transportation pipelines is a relevant problem for the petroleum industry. Significant capital and operatinal cost are associated with the total or partial blockage of production lines. Pigging is the most widely used technique for removing wax deposits. The knowledge of the forces necessary to break and remove a particular wax deposit are key to the safe and a efficient design of a pigging operation. The present work presents an experimental laboratory study of the forces necessary to remove wax deposits inside a duct. The results obtained with the experiments are used to validate predicting models avaiable in the litErature.
12
Brooks, George Patrick 1955. "Forced ventilation removal of chlorinated hydrocarbons in layered, unsaturated soil material: A laboratory evaluation." Thesis, The University of Arizona, 1989. http://hdl.handle.net/10150/276975.
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Helium tracer experiments were conducted to characterize conservative tracer behavior in a wedge-shaped lysimeter containing alternating layers of unsaturated silty sand, and clay loam. Experiments were conducted with trichloroethylene and 1,1,1-trichloroethane to determine if air stripping in unsaturated soil could be characterized by mass transfer from the sorbed to the liquid to the vapor phase. Batch experiments were conducted to measure liquid--vapor mass transfer. Solid-liquid-vapor mass transfer was characterized by measuring the vapor phase re-equilibration after the air stripping experiment. The Discrete State Compartment model was used to simulate a conservative gas tracer. The results were compared to the helium tracer. Liquid-vapor, and solid-liquid-vapor mass transfer were modeled by fitting simulated data to experimental data. The conservative tracer, and mass transfer models were combined to simulate air stripping in unsaturated soil.
13
Lütkenhaus, Davidson. "Engineering understanding of cleaning : effect of chemistry and mechanical forces on soil removal." Thesis, University of Birmingham, 2017. http://etheses.bham.ac.uk//id/eprint/7929/.
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The cleaning of food-based soils is highly relevant in domestic and industrial environments due to the costs associated with these operations as well as the significant consumption of time, water, and energy. Understanding the relationship between chemical and mechanical forces required to clean a surface is a critical step towards optimizing these processes. A complex twophase polymerized grease was developed and characterized with respect to its morphology, component distribution, and chemical composition. A thorough evaluation and physicochemical characterization of the cleaning process of this complex soil from a hard substrate was performed at two different length scales. Results showed that surfactants are more effective at weakening the cohesive interactions within the soil matrix and less effective in removing the adhesive bonds at the soil-substrate interface. A statistical model for cleaning efficiency was developed which described cleaning as a function of chemical and mechanical contributions. The effect of the chemistry on hydration and final cleaning performance was investigated through a definitive model screening and correlated to the tribological forces involved in the process. The model was shown to be applicable to several industrially relevant surfactant systems and revealed that hydration is the main factor driving cleaning of this two-phase soil.
14
Marowa, Ivan [Verfasser], and Achim von [Akademischer Betreuer] Oppen. "Forced Removal and Social Memories in North-western Zimbabwe,c1900-2000 / Ivan Marowa. Betreuer: Achim von Oppen." Bayreuth : Universität Bayreuth, 2015. http://d-nb.info/1073944212/34.
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Klein, Heather A. "Measuring the Removal of Trichloroethylene from Phytoremediation Sites at Travis and Fairchild Air Force Bases." DigitalCommons@USU, 2011. https://digitalcommons.usu.edu/etd/860.
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Past use of trichloroethylene (TCE) as a degreasing solvent for aircraft maintenance has resulted in widespread groundwater contamination at Air Force Bases around the world. Travis AFB in California and Fairchild AFB in Washington are evaluating phytoremediation as a treatment option, since trees have been reported to take up dissolved TCE from shallow groundwater and volatilize it to the atmosphere while enhancing the volatilization of TCE from surrounding soil. Previous studies generally focused on the identification of removal mechanisms. The emphasis of this research was to quantify total TCE removal from phytoremediation demonstration plots at Travis and Fairchild AFBs.
Tree cores, collected using an increment borer and analyzed using headspace GC/MS, were used to determine the relative TCE concentrations within the plume beneath the trees and to estimate the mass of TCE in each tree. To estimate the volatilization of TCE from leaves, a small section of tree branch was placed inside a flow-through glass chamber. Continuous air flow through the chamber maintained normal transpiration and temperature. Air exiting the chamber was sampled for TCE using Tenax® tubes. Humidity probes placed at the chamber entry and exit were used to estimate transpiration. Volatilization of TCE from tree trunk and soil surfaces was measured by enclosing a section of trunk or ground surface within a small stainless steel chamber. Fans in the chamber mixed the air that was recirculated through Tenax® tubes to continuously remove TCE. After a measured time interval, the Tenax® tubes were analyzed for TCE by thermal desorption GC/MS.
By using a Thiessen polygon method, the removal of TCE was estimated to be 839 g/yr at Travis and 18 g/yr at Fairchild with the majority from leaf and soil volatilization. Soil surface volatilization of TCE was greater inside the planted areas than outside the planted areas, indicating that the trees enhance this removal by this mechanism. Based on these estimates phytoremediation removed 5 and 50% of the mass of TCE in the groundwater at Fairchild and Travis Air Force sites, respectively.
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Bihi, Ilyesse. "Removal of microparticles from a surface due to interfacial and shear forces in two-phase flows." Thesis, Lille 1, 2016. http://www.theses.fr/2016LIL10070/document.
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Le décrochage de microparticules adhérant à une surface grâce aux écoulements se rencontre dans de multiples situations où le nettoyage minutieux ou sélectif de parois est crucial. Par exemple, l’industrie agroalimentaire rencontre des problèmes récurrents d’accrochage robuste de bactéries (microparticules) aux parois des lignes de production d’aliments comme le lait ou la viande. Dans cette thèse, l’utilisation d’un écoulement diphasique avec une interface fluide-fluide en complément d’un écoulement monophasique cisaillé a été considérée. L’interaction entre une interface liquide et une particule dépend principalement de l’énergie de surface totale. Elle correspond aux paramètres de mouillage et introduit une force supplémentaire qui peut contribuer à la force totale nécessaire pour le décrochement. Dans le cas d’un décrochement des microparticules et leur collecte par interface fluide-fluide, la stabilité de cette dernière se voit alors changer si sa surface n’est plus apte à accueillir davantage de particules. D’autre part, la dynamique d’une particule ellipsoïde, similaire à une spore, a été étudiée numériquement dans la seconde partie de cette thèse. L’étude a eu comme but de déterminer les conditions pour lesquelles une particule prés d’une paroi peut s’y approcher ou s’en éloigner. Dans la dernière partie nous avons étudié l’influence des conditions initiales et en particulier le séchage sur les forces nécessaires pour le décrochement des sporesFood contamination due to pathogens and spoilage bacteria on surfaces of industrial equipment is a major issue that has not yet found a proper solution. Indeed, despite the set-up of cleaning and disinfection procedures, some bacteria (microparticles) are still commonly found on the surfaces of food processing lines. Traditionally, industrial cleaning procedures involve viscous stresses in a single-phase flow to remove spores from a surface. The present study investigates the use of two-phase flows for improving cleaning procedures. Such system has the advantage of involving interfacial forces that can aid in the removal of microparticles as long as certain wetting conditions are met. This would imply the detachment and collection of the microparticles by the fluid-fluid interface. This collection will in turn affect the dynamics of the interface if its surface is insufficient to accommodate all particles. With respect to viscous stresses in removing particles, a numerical code is developed to study the dynamics of ellipsoids near a solid surface in a shearing flow. The shape of the microparticles in the simulations is set to mimic the spores morphology. Finally, the study examines the effect of the initial environment on the ease of spores removal. In particular, the study investigates the drying conditions that spores undergo in an industrial environment before the cleaning procedures start
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Diamond, J. Oliver. "Quantifying the Removal of Trichloroethylene via Phytoremediation a Hill Air Force Base, Utah Operational Unit 2 Using Recent and Historical Data." DigitalCommons@USU, 2016. https://digitalcommons.usu.edu/etd/4743.
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Trichloroethylene (TCE) is a carcinogenic, chlorinated volatile organic compound that was commonly used as a degreasing solvent for aircraft maintenance at many US Air Force bases. Past improper disposal of TCE has resulted in contaminated groundwater at many of these facilities. Phytoremediation, defined as the use of plants and their associated microorganisms to stabilize or remove contamination, has been implemented as part of a TCE groundwater cleanup at Travis Air Force base near Sacramento, CA and is being considered as a remediation option at other bases. Volatilization of TCE from leaves and the surface of the soil near the trees were shown to be the most important removal mechanisms at the Travis site. Past studies conducted on indigenous trees growing above TCE contaminated groundwater at several Hill Air Force Base (HAFB) locations have also shown that TCE is taken up and volatilized by the trees. However, phytoremediation has not been implemented, in part because of the difficulty in predicting the potential effectiveness of TCE removal over time.
Flow through or recirculating chambers were used to quantify the amount of TCE removed by volatilization through leaf, trunk, and soil surfaces. Tenax™ sorbent tubes, used to collect TCE from the chambers, were analyzed by thermal desorption gas chromatography/mass spectrometry. Tree cores were collected using an incremental borer and analyzed by headspace GC/MS to quantify the TCE mass contained in the trees.
Field measured transpiration stream concentrations (TSC) and groundwater data were used to calculate transpiration stream concentration factors (TSCF) for TCE. Comparing current and historical data, it was found that trees reach a steady state TSCF value of 0.26 after about 15 years.
Using this information, it was predicted that a phytoremediation plot containing 40 poplar trees located in a seep area within HAFB OU2 would remove 4.82 kg of TCE annually. A larger plot covering the entire hillside above this seep (160 trees) could remove up to 19.28 kg of TCE annually, once trees reach a steady state TSCF.
18
Zhang, Wuming. "Towards non-conventional face recognition : shadow removal and heterogeneous scenario." Thesis, Lyon, 2017. http://www.theses.fr/2017LYSEC030/document.
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Ces dernières années, la biométrie a fait l’objet d’une grande attention en raison du besoin sans cesse croissant d’authentification d’identité, notamment pour sécuriser de plus en plus d’applications enlignes. Parmi divers traits biométriques, le visage offre des avantages compétitifs sur les autres, e.g., les empreintes digitales ou l’iris, car il est naturel, non-intrusif et facilement acceptable par les humains. Aujourd’hui, les techniques conventionnelles de reconnaissance faciale ont atteint une performance quasi-parfaite dans un environnement fortement contraint où la pose, l’éclairage, l’expression faciale et d’autres sources de variation sont sévèrement contrôlées. Cependant, ces approches sont souvent confinées aux domaines d’application limités parce que les environnements d’imagerie non-idéaux sont très fréquents dans les cas pratiques. Pour relever ces défis d’une manière adaptative, cette thèse porte sur le problème de reconnaissance faciale non contrôlée, dans lequel les images faciales présentent plus de variabilités sur les éclairages. Par ailleurs, une autre question essentielle vise à profiter des informations limitées de 3D pour collaborer avec les techniques basées sur 2D dans un système de reconnaissance faciale hétérogène. Pour traiter les diverses conditions d’éclairage, nous construisons explicitement un modèle de réflectance en caractérisant l’interaction entre la surface de la peau, les sources d’éclairage et le capteur de la caméra pour élaborer une explication de la couleur du visage. A partir de ce modèle basé sur la physique, une représentation robuste aux variations d’éclairage, à savoir Chromaticity Invariant Image (CII), est proposée pour la reconstruction des images faciales couleurs réalistes et sans ombre. De plus, ce processus de la suppression de l’ombre en niveaux de couleur peut être combiné avec les techniques existantes sur la normalisation d’éclairage en niveaux de gris pour améliorer davantage la performance de reconnaissance faciale. Les résultats expérimentaux sur les bases de données de test standard, CMU-PIE et FRGC Ver2.0, démontrent la capacité de généralisation et la robustesse de notre approche contre les variations d’éclairage. En outre, nous étudions l’usage efficace et créatif des données 3D pour la reconnaissance faciale hétérogène. Dans un tel scénario asymétrique, un enrôlement combiné est réalisé en 2D et 3D alors que les images de requête pour la reconnaissance sont toujours les images faciales en 2D. A cette fin, deux Réseaux de Neurones Convolutifs (Convolutional Neural Networks, CNN) sont construits. Le premier CNN est formé pour extraire les descripteurs discriminants d’images 2D/3D pour un appariement hétérogène. Le deuxième CNN combine une structure codeur-décodeur, à savoir U-Net, et Conditional Generative Adversarial Network (CGAN), pour reconstruire l’image faciale en profondeur à partir de son homologue dans l’espace 2D. Plus particulièrement, les images reconstruites en profondeur peuvent être également transmise au premier CNN pour la reconnaissance faciale en 3D, apportant un schéma de fusion qui est bénéfique pour la performance en reconnaissance. Notre approche a été évaluée sur la base de données 2D/3D de FRGC. Les expérimentations ont démontré que notre approche permet d’obtenir des résultats comparables à ceux de l’état de l’art et qu’une amélioration significative a pu être obtenue à l’aide du schéma de fusionIn recent years, biometrics have received substantial attention due to the evergrowing need for automatic individual authentication. Among various physiological biometric traits, face offers unmatched advantages over the others, such as fingerprints and iris, because it is natural, non-intrusive and easily understandable by humans. Nowadays conventional face recognition techniques have attained quasi-perfect performance in a highly constrained environment wherein poses, illuminations, expressions and other sources of variations are strictly controlled. However these approaches are always confined to restricted application fields because non-ideal imaging environments are frequently encountered in practical cases. To adaptively address these challenges, this dissertation focuses on this unconstrained face recognition problem, where face images exhibit more variability in illumination. Moreover, another major question is how to leverage limited 3D shape information to jointly work with 2D based techniques in a heterogeneous face recognition system. To deal with the problem of varying illuminations, we explicitly build the underlying reflectance model which characterizes interactions between skin surface, lighting source and camera sensor, and elaborate the formation of face color. With this physics-based image formation model involved, an illumination-robust representation, namely Chromaticity Invariant Image (CII), is proposed which can subsequently help reconstruct shadow-free and photo-realistic color face images. Due to the fact that this shadow removal process is achieved in color space, this approach could thus be combined with existing gray-scale level lighting normalization techniques to further improve face recognition performance. The experimental results on two benchmark databases, CMU-PIE and FRGC Ver2.0, demonstrate the generalization ability and robustness of our approach to lighting variations. We further explore the effective and creative use of 3D data in heterogeneous face recognition. In such a scenario, 3D face is merely available in the gallery set and not in the probe set, which one would encounter in real-world applications. Two Convolutional Neural Networks (CNN) are constructed for this purpose. The first CNN is trained to extract discriminative features of 2D/3D face images for direct heterogeneous comparison, while the second CNN combines an encoder-decoder structure, namely U-Net, and Conditional Generative Adversarial Network (CGAN) to reconstruct depth face image from its counterpart in 2D. Specifically, the recovered depth face images can be fed to the first CNN as well for 3D face recognition, leading to a fusion scheme which achieves gains in recognition performance. We have evaluated our approach extensively on the challenging FRGC 2D/3D benchmark database. The proposed method compares favorably to the state-of-the-art and show significant improvement with the fusion scheme
19
Guichard, Bastien. "Contribution à la définition d'un processus de polissage robotisé. Application aux pièces aéronautiques en acier à haute résistance." Thesis, Clermont-Ferrand 2, 2015. http://www.theses.fr/2015CLF22619.
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Dans le cas des pièces aéronautiques de grandes dimensions et de formes complexes nécessitant un bon état de surface, les opérations de polissage sont la plupart du temps réalisées manuellement par des opérateurs spécialisés. Ces opérations étant longues, pénibles et coûteuses, il paraît pertinent de s’intéresser à leur automatisation. Dans ces travaux de thèse, nous nous intéressons à la mise en place d’un processus de polissage robotisé pour un train d'atterrissage en acier à haute résistance. La définition du processus robotisé passe par la définition des outils adéquats (taille de grain, forme et souplesse), des conditions de polissage (effort, vitesse de coupe, vitesse d’avance, angle de dépinçage et recouvrement) et le réglage des paramètres de la commande en effort en fonction du matériau à polir et de la spécification de rugosité visée. Un modèle d’enlèvement de matière est ensuite proposé afin de maîtriser le défaut d’état de surface généré pour des outils « disques ». Une campagne expérimentale permet enfin de valider la mise en œuvre du robot et du processus de polissage sur une pièce spécifique, notamment en ce qui concerne la chaîne numériqueIn the case of aircraft large parts and complex shapes requiring a good finish state, polishing operations are mostly performed manually by specialized operators. These operations are long, painful and expensive, it seems relevant to be interested in their automation. In the thesis work, we focus on the development of a robotic polishing process for high strength steel landing gear. The definition of the robotic process involves the definition of appropriate tools (grain size, shape and flexibility), polishing conditions (force, cutting speed, feed rate, inclination angle and overlap) and adjustment of parameters the force control based on the material to be polished and the specification roughness. A material removal model is then proposed to control the surface state generated for discs tools. Finally, an experimental campaign validates the implementation of the robot and the polishing process on a specific part, in particular as regards the numerical chain
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Delaux, Sebastien Serge. "Physical and numerical modelling of particle settlement in a turbulent flow: implication for the settlement of algal propagules." Thesis, University of Canterbury. School of Biological Sciences, 2009. http://hdl.handle.net/10092/4430.
Full textAbstract:
A fundamental stage in rocky-shore seaweed life history is the recruitment process involving external fertilisation and then settlement of the
propagules on a suitable substrate. The ultimate step in this settlement
stage is the crossing of the viscous sub-layer and attachment to the substrate. Given the extreme conditions met in the intertidal zone, propagules can be dislodged at any time before they secure a strong enough anchoring.
Flow conditions and propagule properties are key to this process. The
settlement process under turbulent conditions was recreated within a
stirred benthic chamber for five different species. Whereas propagule
properties (size, density) vary with species, and propagules are adapted to
the different conditions in the intertidal, they exhibit the same
settlement behaviour. They nevertheless exhibit different settling
velocities and settlement thresholds. Several methods of characterisation
of the tank flow from particle tracking velocimetry and acoustic Doppler velocimetry data are reviewed, as well as an analytical model. Turbulent settling was found to be independent of the well-mixed tank bulk flow and to depend only on the boundary-layer mechanics. A model of settlement threshold is presented from which propagule mucilage adhesiveness estimates are derived, leading to good
correlations between adult plant exposure and the stickiness of its propagules and to the conclusion that settlement can only occur in calm conditions.
To extend the work, computational fluid dynamic techniques are developed by extending the Gerris Flow Solver. A 2-D approach to tank modelling and a pilot study of expansion to 3-D is described. This extends the perspective
given by the experiments, notably through output of the hydrodynamical
forces experienced by the propagules. Finally, in the view of realizing direct numerical simulations of propagule behaviour in the viscous sub-layer, a new and unique 2-D/3-D fully conservative solid/fluid interaction model is developed and tested with success.
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Cheng, Ming-Yi. "An experimental investigation into tool wear in micro-drilling of aluminium, aluminium/copper metal alloys and carbon fibre reinforced composites." Thesis, Brunel University, 2017. http://bura.brunel.ac.uk/handle/2438/14613.
Full textAbstract:
Limitation of conventional machining equipment has become a growing concern over the past two decades due to the demands for greater machining accuracy in today’s manufacturing. The development of micro-machining has therefore attracted significant attention; it signifies the advancement of national economy as well as the level of accuracy manufacturing industry could achieve. While the connection between tool lifespan, cost of machining and throughput is well established, the factor of tool lifespan appears to have more significance since the miniaturization of tool could lead to further performance concerns such as its lack of strength and durability. On the other hand, raising feed rate and spindle rotation speed are the two common approaches for increasing manufacturing throughput. Such approaches tend to cause an increase in the thrust force subjecting the tool to greater stress, which is the main cause of tool wear and even tool failure. Through literature review and preliminary experiments, it was found that spot-drill is often done prior to micro-drilling since it prepares a pre-drill countersunk hole that helps the alignment of tool for subsequent micro-drilling. Although such pre-drill step does improve the micro-drilling operation, the fundamental issue of tool diameter difference still remains. Often the tool used for pre-drill has a bigger diameter than the one for micro-drilling although a significant difference is always something to be avoided. This is because the difference has to be picked up by the tool used for micro-drilling and is directly linked to the wear caused by increased thrust force. In this research the operation of micro-drilling is investigated via mathematical models. Such operation is further broken down into various steps and stages so more detailed description can be achieved. The findings are then further enhanced by simulation based on the 3D model of micro-drilling. Three materials were selected for this research: Al 6061T, Al/Cu metal alloy panel and Carbon fibre reinforced composites. Such a selection enables the study of individual characteristics of different materials and the variation in respective thrust forces. Finally, Conclusions present the summary of the main findings from micro-drilling process analysis based on research and investigation shown in earlier chapters. By combining actual measurements on micro-drilling and mathematic model this research hopefully would improve the understanding towards micro-drilling processes.
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Hayes-Roberts, Hayley Elizabeth. "Frameworks of representation: A design history of the District Six Museum in Cape Town." University of the Western Cape, 2020. http://hdl.handle.net/11394/7282.
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Philosophiae Doctor - PhDSince 1994, the District Six Museum, in constructing histories of forced removals from District Six, Cape Town, commenced as a post-apartheid memory project which evolved into a memorial museum. Design has been a central strategy claimed by the museum in its process of making memory work visible to its attendant publics evolving into a South African cultural brand. Co-design within the museum is aesthetically infused with sensitively curated exhibitions and a form of museumisation, across two tangible sites of engagement, which imparts a unique visual language. The term design became extraordinarily popular in contemporary Cape Town, where the city was - in 2014 -the World Design Capital. Yet at the same time as design was being inscribed into the public imaginary, it was simultaneously curiously undefined although influential in shifting representational aesthetics in the city. This research seeks to ask questions about this proliferation of interest in design and to examine this through a close reading of the work of the District Six Museum situated near District Six. In particular, micro and macro design elements are explored as socio-cultural practice in re-imagining community in the city that grew out of resistance and cultural networks. Various design strategies or frameworks of representation sought to stabilize and clarify individual and collective pasts enabling and supporting ex-residents to reinterpret space after loss, displacement and separation and re-enter their histories and the city. Post-apartheid museum design modes and methodologies applied by the District Six Museum as museumisation disrupts conventional historiographies in the fields of art, architectural and exhibition design, where the focus is placed on temporal chronologies, in a biographic mode profiling examples of works and designers/artists. Instead, the research contextualises the work of design as making in a more open sense, of exploring the very constructedness of the museum as a space of method, selection, process and representation thereby asking questions about this reified term design as method and practice. The designing ways of the District Six Museum contribute to understanding idioms mediated through design frameworks allowing for a departure from the limited ways design history has been written. Through an unlayering of projects, practices and an examination of archival case studies, exhibition curation, the adaptive reuse of buildings and through institutional rebranding my argument is that the particularities of the claims to design work at the District Six Museum provide a rich case for relating to other contemporaneous processes of making apartheid’s spatial practices visible as projects such as this claim community. Therefore seeking to demystify how this community museum ‘making’ has been fashioned through an investment in various design disciplines, forms and practices revealing the inherent complexity in doing so.
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Tonel, Mariana Zancan. "INTERAÇÃO DE MOLÉCULAS AROMÁTICAS EM GRAFENO PURO E FUNCIONALIZADO VIA SIMULAÇÃO COMPUTACIONAL Santa Maria, RS 2017." Centro Universitário Franciscano, 2017. http://www.tede.universidadefranciscana.edu.br:8080/handle/UFN-BDTD/578.
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Graphene is a nanomaterial that has several applications including drug delivery and pollutant remover. However, graphene is hydrophobic, which makes it difficult to apply in biological media, and one of the alternatives is through functionalization. At the same time, aromatic molecules are precursors of several essential compounds for life, and are also important in industry. However, some of them are pollutants that can severely affect people and the environment, so developing effective removal methods is extremely interesting. Some molecules of biological interest like dopamine and serotonin have an aromatic part, recent studies show the use of these molecules as mediators for specific and selective drug delivery. Therefore, the study of the interaction of these molecules as pure and modified graphene is of great importance in the biomedical area as well as for diagnostic and treatment studies. In this work, we perform a theoretical study through the density functional theory; initially we analyze the changes caused by the effect of the concentration of the functional groups -COOH, -COH, -OH, -O- or -NH2 on graphene. The results show that in all cases it is possible to modulate the electronic properties depending on the number and location of the groups. Subsequently, we analyzed the graphene pure and functionalized with a group -COOH, -COH, -OH, -O- or -NH2, with the molecules of biological interest as dopamine, serotonin and the pollutants: benzene, aniline, benzoic acid and phenol. The results show that all interactions occur under a physical adsorption regime, there are no changes in the original geometric structures of the molecules after adsorption, it may be of interest to create possible routes as mediators for the delivery of drugs and to assist in the treatment of various diseases or in a system of removal of pollutants based on pristine and modified graphene. Finally, we developed a method to parameterize the benzene-benzene and benzene-graphene force field through the data obtained from the ab initio calculations, the results obtained agree with studies described in the literature. Thus, this work presents the understanding through the simulation of the biomedical part for drug delivery systems, and removal of pollutants, in addition to the parameterization to be used in simulations of the biological environment which may aid in the development of future experimental studies.
O grafeno é um nanomaterial que possui diversas aplicações tecnológicas entre elas como carreador de fármacos e removedor de poluentes. No entanto, o grafeno é hidrofóbico, o que dificulta sua aplicação em meios biológicos, sendo que uma das alternativas para controlar este problema é através de funcionalizações. Paralelamente, moléculas aromáticas são precursoras de diversos compostos imprescindíveis para a vida, e também são importantes na indústria. No entanto, algumas delas são poluentes que podem afetar severamente as pessoas e o meio ambiente. Assim, o desenvolvimento de métodos efetivos para remoção desses é extremante importante. Algumas moléculas de interesse biológico como a dopamina e serotonina apresentam parte aromática. Estudos recentes têm mostrado a utilização dessas moléculas como mediadoras para entrega de fármacos específica e seletiva. Portanto, o estudo dessas moléculas visando este tipo de aplicação é de grande importância na área biomédica. Realizamos um estudo teórico através da Teoria do Funcional da Densidade. Inicialmente, analisamos as alterações causadas pelo efeito da concentração de grupos funcionais -COOH, -COH, -OH, -O- ou -NH2 no grafeno. Os resultados mostram que em todos os casos é possível modular as propriedades eletrônicas dependendo do número e do local dos grupos. Posteriormente, analisamos o grafeno puro e funcionalizado com um grupo –COOH, -COH, -OH, –O- ou -NH2, com as moléculas de interesse biológico dopamina, serotonina e os poluentes benzeno, anilina, ácido benzóico e fenol. Os resultados mostram que todas as interações ocorrem sob um regime de adsorção física, sem alterações nas estruturas geométricas originais das moléculas após adsorção. Esses resultados são de interesse para criar possíveis rotas como mediadores para a entrega de fármacos e auxiliar no tratamento de várias doenças ou ainda em um sistema de remoção de poluentes baseados no grafeno puro e modificado. E, por fim, desenvolvemos um novo método para parametrizar campo de força do benzeno-benzeno e benzeno-grafeno através dos dados obtidos dos cálculos ab initio. Os resultados obtidos concordam com estudos descritos na literatura. Dessa forma, este trabalho apresenta a compreensão através da simulação da parte biomédica para sistemas de drug delivery, e remoção de poluentes, além da parametrização para ser usado em simulações do meio biológico o que poderá auxiliar no desenvolvimento de estudos experimentais futuros.
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Gonçalves, Thais Marques Simek Vega 1980. "Masticatory function in partially edentulous patients after rehabilitation with removable and fixed prosthesis over osseointegrated implants = Função mastigatória de pacientes parcialmente edêntulos após reabilitação com próteses removíveis e fixas sobre implantes osseointegrados." [s.n.], 2013. http://repositorio.unicamp.br/jspui/handle/REPOSIP/288671.
Full textAbstract:
Orientador: Renata Cunha Matheus Rodrigues-GarciaTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba
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Resumo: Estudos revelam melhora na mastigação após o uso de próteses sobre implantes osseointegrados. Entretanto, poucos são aqueles que avaliam a mastigação de pacientes parcialmente edêntulos, comparando a função mastigatória após a reabilitação por meio de diferentes próteses parciais, o qual foi o objetivo deste ensaio clínico pareado. Para tanto, foram selecionados 12 voluntários (8 gênero feminino, idade média 62.6 ± 7.8 anos), apresentando edentulismo total superior e parcial inferior (classe I de Kennedy), os quais receberam, de forma sequencial, próteses parciais removíveis (PPR), PPR com encaixe implanto-retido (PPRI) e prótese parcial fixa sobre implantes (PPFI). Todos os tratamentos foram realizados na mandíbula e utilizados por 2 meses antes da avaliação mastigatória, enquanto a maxila recebeu uma nova prótese total que foi utilizada durante todo o estudo. A mastigação foi avaliada por meio da mensuração da performance mastigatória (PM), índice de trituração dos alimentos (ITA), força máxima de mordida (FMM), espessura dos músculos masseter e temporal, movimento mastigatório, limiar de deglutição (LD), habilidade mastigatória, estado nutricional, qualidade de vida (QV) e satisfação do paciente. Foi realizada a análise exploratória dos dados e aplicada análise de variância para medidas repetidas seguido de teste de Tukey-Kramer para as comparações múltiplas entre os tratamentos. Todas as análises foram realizadas utilizando SAS software (release 9.1, 2003; SAS Institute Inc., Cary, USA) (p ? 0.05). A PM melhorou consideravelmente após o uso de PPRI e PPFI com aumento de 85% e 87%, respectivamente. Resultados similares foram observados em relação ao ITA e à FMM com aumento (p ? 0.0001) de 91% e 62% no ITA de 79% e 62% na FMM após o uso de PPRI e PPFI, respectivamente. Independente do tipo de prótese, o uso de PPRI e PPFI aumentou a espessura do masseter durante a contração voluntária máxima (p ? 0.0001) e alterou o movimento mastigatório, reduzindo o tempo total do ciclo, bem como a duração das fases de abertura e fechamento (p ? 0.05). A habilidade mastigatória melhorou após o uso da PPRI e PPFI, independente do alimento avaliado. O LD foi alterado pelo tratamento reabilitador, com redução no número de ciclos e tamanho da partícula triturada, sendo os menores valores observados com o uso da PPFI. Houve aumento no consumo de fibras (p = 0.007), cálcio (p = 0.001) e ferro (p = 0.02) após o uso de PPFI, além da redução no consumo de alimentos com altos níveis de colesterol (p = 0.02). A satisfação aumentou (p ? 0.05) e o impacto da saúde oral na QV reduziu, tanto no score geral (p = 0.04) quanto no domínio de dor física (p = 0.02) após o uso da PPFI. A reabilitação de pacientes parcialmente edêntulos com PPRI e PPFI melhorou significativamente a função mastigatória e a magnitude do efeito relacionou-se ao tipo de prótese
Abstract: Studies revealed the masticatory improvement after the use of prosthesis over dental implants. However, few are those who evaluated the chewing of partially edentulous patients, comparing the masticatory function after treatment with different partial dentures, which was the aim of this paired clinical trial. Therefore, 12 volunteers (8 females, mean age 62.6 ± 7.8 years) presenting total edentulism in maxilla and partial edentulism in the mandible (Kennedy class I) were selected and received, in a sequential way, a conventional removable partial dentures (RPD), implant-retained partial dentures (IRPD) and implant fixed partial denture (IFPD). All treatment were assembled in the mandible and used for 2 months, while the edentulous maxilla received a new complete denture which was used throughout the study. Mastication was assessed by measuring masticatory performance (MP), food comminution index (FCI), maximum bite force (MBF), masseter and temporal muscle thickness, chewing movements, swallowing threshold (ST), masticatory ability, nutritional status, quality of life (QOL) and patient satisfaction. Data were analyzed and repeated measures analysis of variance was applied followed by Tukey-Kramer multiple for comparisons between treatments. All analyzes were performed using SAS software (release 9.1, 2003, SAS Institute Inc., Cary, USA) (p ? 0.05). MP greatly improved after IRPD and IFPD use with an increase of 85% and 87% respectively. Similar results were observed in respect to FCI and MBF with an increase (p ? 0.0001) of 91% and 62% in FCI and of 79% and 62% in MBF after the IRPD and IFPD use, respectively. Regardless the prosthesis type, the use of IRPD and IFPD increased the masseter thickness during maximum voluntary clenching (p ? 0.0001) and altered the chewing movements, reducing the total cycle time, as well as the duration of opening and closing phases (p ? 0.05). MA improved after IRPD and IFPD use, irrespectively of the food rated. ST was affected by prosthetic treatment, showing a reduction in the number of chewing cycles and in the size of the comminuted particle, with the lowest values observed after IFPD use. There was a raise in fiber (p = 0.007), calcium (p = 0.001) and iron (p = 0.02) intake after the IFPD use and a reduction in the intake of food with high cholesterol levels (p = 0.02). Patients satisfaction also increased (p ? 0.05) and the impact of oral health on QOL decreased in overall score (p = 0.04) and in the physical pain domain (p = 0.02) after the IFPD use. The rehabilitation of partially edentulous patients with IRPD and IFPD significantly improved masticatory function and the magnitude of the effect was related to the prosthesis type
Doutorado
Protese Dental
Doutora em Clínica Odontológica
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Hendriko, ? "Advanced virtual simulation for optimal cutting parameters control in five axis milling." Thesis, Clermont-Ferrand 2, 2014. http://www.theses.fr/2014CLF22464/document.
Full textAbstract:
La thèse concerne l’usinage à 5 axes de formes complexes. Le but est d’estimer le plus précisément possible les efforts induits par la coupe pour ajuster la vitesse d’avance et gagner en performance. Pour cela, il est nécessaire d’estimer les engagements radial et axial de la fraise à chaque instant. Ce calcul est rendu particulièrement complexe à cause de la forme de la pièce, de la forme du brut et de la complexité de la géométrie de l’outil. Les méthodes usuelles par Zbuffer sont particulièrement couteuses en temps de calcul. Dans ces travaux nous proposons une méthode de calcul rapide à partir d’une modélisation du contact dans toutes les situations envisageables. Différentes simulations et expérimentations ont permis de valider la précision expérimentalementThis study presents a simple method to define the Cutter Workpiece Engagement (CWE) during sculptured surface machining in five-axis milling. The instantaneous CWE was defined by determining two engagement points, lowermost engagement (LE)-point and uppermost engagement (UE)-point. LE-point was calculated using a method called grazing method. Meanwhile the UE-point was calculated using a combination of discretization and analytical method. During rough milling and semi-finish milling, the workpiece surface was represented by vertical vector. The method called Toroidal–boundary was employed to obtain the UE-point when it was located on cutting tool at toroidal side. On the other hand, the method called Cylindrical-boundary was used to calculate the UE-point for flat-end cutter and cylindrical side of toroidal cutter. For a free-form workpiece surface, a hybrid method, which is a combination of analytical method and discrete method, was used. All the CWE models proposed in this study were verified and the results proved that the proposed method were accurate. The efficiency of the proposed model in generating CWE was also compared with Z-mapping method. The result confirmed that the proposed model was more efficient in term of computational time. The CWE model was also applied for supporting the method to predict cutting forces. The test results showed that the predicted cutting force has a good agreement with the cutting force generated from the experimental work
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Grandchamps, Nicholas. "Justice: The Use of Food, Education, and the Law to Combat Human Trafficking in Sub-Saharan Africa." Honors in the Major Thesis, University of Central Florida, 2014. http://digital.library.ucf.edu/cdm/ref/collection/ETH/id/1597.
Full textAbstract:
Human trafficking is an ever-growing crime in this century. It is estimated that there are 29.8 million slaves around the world today - 16.36% of which are located in sub-Saharan Africa.
The sub-Saharan region is a region in which human trafficking is combatted ineffectively due to a lack of food, lack of access to education, lack of post-education opportunities and lack of
proper legislation. This thesis explores the environment in which human trafficking is taking place in sub-Saharan Africa, and proposes potential changes that will theoretically disallow
human trafficking to take place in the region. The only way in which an environment conducive to trafficking in persons will ever change is through establishing partnerships amongst governments, non-governmental organizations (NGOs), and other international organizations. Through the analysis of case law from the United Nations Human Trafficking Case Law Database, data from the World Bank, the United States State Department Trafficking in Persons Reports, the United Nations Global Reports on Human Trafficking, and various reports from NGOs, this thesis evaluates the approaches taken by various governments in sub-Saharan Africa to change the environment in which human trafficking thrives. Through raising awareness of the environment of sub-Saharan Africa, and by describing three ways in which human trafficking can be combatted effectively, such as the use of food, education, and the law, this thesis contributes not only to the legal discipline, but also to helping combat trafficking in persons effectively throughout the world.B.A.
Bachelors
Legal Studies
Health and Public Affairs
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Muller, Isabelle. "Restauration de marais temporaires et de pelouses méso-xériques à partir d’anciennes rizières : Rôle respectif des filtres dans l'assemblage des communautés." Thesis, Avignon, 2013. http://www.theses.fr/2013AVIG0329/document.
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La restauration écologique est considérée comme un des moyens susceptibles d’enrayer la perte de la biodiversité. Les changements d’occupation du sol peuvent être des opportunités pour restaurer des écosystèmes dégradés par les activités agricoles. C’est notamment le cas du projet participatif du domaine du Cassaïre, situé dans le delta du Rhône, qui vise à recréer sur d’anciennes rizières des écosystèmes méditerranéens favorables à l’activité cynégétique. Deux écosystèmes sont plus particulièrement visés, les marais temporaires et les pelouses méso-xériques. Les objectifs de la thèse sont de mettre en évidence les principaux mécanismes concourant à l’installation d’une communauté végétale, de tester des techniques de restauration et d'en évaluer les conséquences pour les communautés végétales mais aussi pour d'autres compartiments de l'écosystème. En l’absence d’espèces cibles dans le pool régional d’espèces, l’introduction de ces espèces est nécessaire en addition de la restauration des conditions abiotiques. L’étrépage et le transfert de sol pour la communauté des marais permettent une augmentation des espèces cibles et de la similarité avec la communauté de référence. Cette technique apparaît moins pertinente pour la communauté d’invertébrés aquatiques. Le succès contrasté du transfert de sol souligne les risques à ne pas privilégier qu’un nombre restreint d’indicateurs de restauration, ne reflétant pas l’ensemble de l’écosystème. L’étrépage de sol suivi d’un transfert de foin semble être une combinaison pertinente pour recréer la communauté végétale de pelouses, même si les résultats obtenus, probablement en raison d’une compétition élevée, sont moins convaincants que pour les marais temporaires. Nos résultats obtenus pour la grande majorité en mésocosmes, s’ils ne concernent que les premières étapes de la restauration, mettent cependant en évidence des techniques de restauration qui paraissent pertinentes pour installer certaines composantes des deux écosystèmes de référence. Ces résultats, par leurs limites, suggèrent néanmoins de privilégier la conservation in situ des habitats naturels plutôt que de chercher à les restaurer après qu’ils aient été détruitsEcological restoration is considered as one approach to slow down the loss of biodiversity. Changes in land-uses may be an opportunity to restore ecosystems degraded by agricultural activities. This is the case of the participatory project of the Cassaïre site, located in the Rhône delta, which aims at recreating Mediterranean ecosystems favorable to hunting on former ricefields. Two ecosystems are targeted, temporary wetlands and meso-xeric grasslands. The aims of the thesis are to highlight the main drivers of plant community establishment, to test restoration techniques and to evaluate their effects on plant communities but also on other compartments of the ecosystem. In the absence of target species in the regional species pool, the introduction of these species is necessary in addition to the restoration of abiotic conditions. Topsoil removal and soil transfer for wetland communities allow an increase of target species and of similarity with the reference community. This technique appears to be less relevant for aquatic invertebrate community. The contrasted successful of soil transfer highlights the risks of favoring some indicators of restoration success, as they may not reflect the entire ecosystem. Topsoil removal and hay transfer seem to be a relevant combination to recreate grassland plant community, although the results obtained are less convincing than for temporary wetland, probably due to high competition. Our results, obtained in mesocosms, even if they relate only to the early stages of recovery, provide restoration techniques that seem relevant to establish some components of the two reference ecosystems. These results, by their limitations, however, suggest focusing on in situ conservation of natural habitats rather than trying to restore them after they were destroyed.Keywords: Biodiversity, Community ecology, Restoration
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Do, Thanh Ha. "Sparse representations over learned dictionary for document analysis." Thesis, Université de Lorraine, 2014. http://www.theses.fr/2014LORR0021/document.
Full textAbstract:
Dans cette thèse, nous nous concentrons sur comment les représentations parcimonieuses peuvent aider à augmenter les performances pour réduire le bruit, extraire des régions de texte, reconnaissance des formes et localiser des symboles dans des documents graphiques. Pour ce faire, tout d'abord, nous donnons une synthèse des représentations parcimonieuses et ses applications en traitement d'images. Ensuite, nous présentons notre motivation pour l'utilisation de dictionnaires d'apprentissage avec des algorithmes efficaces pour les construire. Après avoir décrit l'idée générale des représentations parcimonieuses et du dictionnaire d'apprentissage, nous présentons nos contributions dans le domaine de la reconnaissance de symboles et du traitement des documents en les comparants aux travaux de l'état de l'art. Ces contributions s'emploient à répondre aux questions suivantes: La première question est comment nous pouvons supprimer le bruit des images où il n'existe aucune hypothèse sur le modèle de bruit sous-jacent à ces images ? La deuxième question est comment les représentations parcimonieuses sur le dictionnaire d'apprentissage peuvent être adaptées pour séparer le texte du graphique dans des documents? La troisième question est comment nous pouvons appliquer la représentation parcimonieuse à reconnaissance de symboles? Nous complétons cette thèse en proposant une approche de localisation de symboles dans les documents graphiques qui utilise les représentations parcimonieuses pour coder un vocabulaire visuelIn this thesis, we focus on how sparse representations can help to increase the performance of noise removal, text region extraction, pattern recognition and spotting symbols in graphical documents. To do that, first of all, we give a survey of sparse representations and its applications in image processing. Then, we present the motivation of building learning dictionary and efficient algorithms for constructing a learning dictionary. After describing the general idea of sparse representations and learned dictionary, we bring some contributions in the field of symbol recognition and document processing that achieve better performances compared to the state-of-the-art. These contributions begin by finding the answers to the following questions. The first question is how we can remove the noise of a document when we have no assumptions about the model of noise found in these images? The second question is how sparse representations over learned dictionary can separate the text/graphic parts in the graphical document? The third question is how we can apply the sparse representation for symbol recognition? We complete this thesis by proposing an approach of spotting symbols that use sparse representations for the coding of a visual vocabulary
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Kyrgyzova, Khrystyna. "Stéréophotométrie non-calibrée de surfaces non-Lambertiennes. Application à la reconstruction de surface de colonies microbiennes." Phd thesis, Université Paris Sud - Paris XI, 2014. http://tel.archives-ouvertes.fr/tel-01063285.
Full textAbstract:
La thèse est dédiée au problème de la stéréophotométrie non-Lambertienne sans connaissance a priori sur les conditions d'illumination et son application aux images de boîte de Pétri. Pour obtenir une bonne reconstruction de surfaces non-Lambertiennes, il est proposé de traiter une séquence d'entrée en deux étapes: premièrement il faut supprimer les effets spéculaires et obtenir ainsi des images de surface 'pseudo-Lambertienne'. Ensuite dans une deuxième étape à partir de ces images une reconstruction stéréophotométrique Lambertienne sans aucune information préalable sur les directions d'illumination est effectuée. Dans ce travail nous proposons deux méthodes originales respectivement pour la suppression de spécularités et la reconstruction de surface sans information a priori. Les méthodes proposées sont appliquées pour la caractérisation des colonies microbiennes.La spécularités est un effet optique lié à la nature physique complexe des objets. Il est utile pour la perception humaine des objets 3D mais il gêne le processus de traitement automatique d'images. Pour pouvoir appliquer le modèle Lambertien à la stéréophotométrie, les spécularités doivent être supprimées des images d'entrée. Nous proposons donc une méthode originale pour la correction des zones spéculaires adaptée pour une reconstruction ultérieure. L'algorithme proposé est capable de détecter les spécularités comme des valeurs anormalement élevées d'intensité dans une image de la séquence d'entrée, et de les corriger en utilisant les informations des autres images de la séquence et une fonction de correction continue. Cette méthode permet de faire la suppression des spécularités en préservant toutes les autres particularités de distribution de lumière qui sont importantes pour la reconstruction de surface.Après nous proposons une technique de reconstruction stéréophotométrique de surface Lambertienne sans connaissance a priori sur l'illumination. Le modèle mis en œuvre consiste en quatre composantes, deux composantes (albédo et normales) permettent de d'écrire des propriétés de surface et deux autres (intensités des sources de lumière et leurs directions) décrivent illumination. L'algorithme proposé de reconstruction utilise le principe de l'optimisation alternée. Chaque composante du modèle est trouvée itérativement en fixant toutes les variables sauf une et en appliquant des contraintes de structures, valeurs et qualité pour la fonction d'optimisation. Un schéma original de résolution permet de séparer les différents types d'information inclus dans les images d'entrée. Grâce à cette factorisation de matrices, la reconstruction de surface est faite sans connaissance préalable sur les directions de lumière et les propriétés de l'objet reconstruit. L'applicabilité de l'algorithme est prouvée pour des donnés artificielles et des images de bases publiques pour lesquelles la vérité terrain sur les surfaces des objets est disponible.La dernière partie de la thèse est dédiée à l'application de la chaine complète proposée pour le traitement d'images de boîte de Pétri. Ces images sont obtenues en utilisant les sources de lumières complexes qui sont supposées être inconnues pour le processus de reconstruction. L'évaluation de surfaces de colonies microbiennes s'est révélée être une étape importante pour l'analyse visuelle et automatique des colonies. La chaine proposée est efficace pour ce type de données et permet de compléter les informations d'images par de la surface 3D.
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Jaunatre, Renaud. "Dynamique et restauration d’une steppe méditerranéenne après changements d’usages (La Crau, Bouches-du-Rhône, France)." Thesis, Avignon, 2012. http://www.theses.fr/2012AVIG0324/document.
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La restauration écologique a été identifiée comme une approche permettant notamment de ralentir la perte de biodiversité et de maintenir tous les biens et services issus de cette biodiversité desquels dépend le bien être de notre civilisation actuelle. Cette restauration des écosystèmes se base sur des connaissances provenant à la fois de l'écologie des communautés et de l’écologie de la restauration. Les objectifs de la thèse sont donc de comprendre la dynamique d’une steppe méditerranéenne après changements d’usage ainsi que la mise en oeuvre de techniques qui pourraient être appliquées à la restauration de cet écosystème après une perturbation anthropique sévère. La thèse a pour objet d'étude la steppe méditerranéenne de la plaine de Crau, et notamment d’anciennes cultures pour étudier la recolonisation spontanée après perturbation et le projet de réhabilitation à grande échelle de Cossure pour les expérimentations sur les techniques de restauration. En ce qui concerne la dynamique après une perturbation anthropique exogène sévère, nous avons confirmé la faible résilience de la communauté végétale steppique à la fois à moyen (30-40 ans) et long terme (150 ans), tandis que les paramètres du sol et le taux d'infestation des mycorhizes sont résilients sur le long terme. En outre, nous avons confirmé le rôle joué par les trois filtres dans la recolonisation des communautés végétales. En ce qui concerne la steppe de la Crau, la recolonisation est déterminée en premier par le filtre abiotique, puis par le filtre de dispersion et enfin par le filtre biotique. Compte tenu de la faible résilience de la communauté, nous avons testé plusieurs techniques de restauration appliquées à grande échelle au sein du projet de réhabilitation de Cossure: le semis d’espèces nurses, l'étrépage de sol, le transfert de foin et le transfert de sol. Afin d'évaluer l'efficacité des techniques de restauration, nous avons développé des indices pour mesurer « l 'intégrité » de la structure de la communauté permettant de distinguer les abondances inférieures des abondances supérieures par rapport à la communauté de référence. Les meilleurs résultats ont été obtenus avec le transfert du sol, suivi par l’étrépage de sol, puis le semis d’espèces nurses et enfin le transfert de foin. Ces résultats ont toutefois confirmé la difficulté de restaurer totalement la communauté végétale steppique. Les recherches menées au sein de cette thèse montrent que les connaissances actuelles en matière de restauration écologique permettent de restaurer au moins partiellement certaines composantes de cet écosystème, mais suggèrent de mettre un maximum de moyens pour la conservation in situ des habitats naturels plutôt que de devoir les restaurer après qu'ils aient été détruitsEcosystem restoration has been identified as one approach to slow down the loss of biodiversity and to protect all the biodiversity-based goods and services from which humankind benefits. Restoration feeds from knowledge coming from both community ecology and restoration ecology. The objectives of the thesis are to provide insights on both the dynamics of a mediterranean steppe after changes in land-use and the implementation of techniques which could be applied to restore this ecosystem after severe anthropogenic disturbances. The thesis takes as a study object the La Crau Mediterranean steppe, and especially former cultivated fields to study the recovery after cultivation and the Cossure large scale rehabilitation project to experiment rehabilitation and restoration techniques. Concerning dynamics after severe exogenous anthropogenic disturbances, we confirmed the low resilience of the steppe plant community both at mid- (30-40 years) and long-term (150 years) while the resilience of soil parameters and mycorrhizal infestation rate are effective on the long-term. Moreover we confirmed the role played by the three filters in the plant community recovery and found that for the La Crau steppe, this is firstly driven by the abiotic filter, then by the dispersion filter and finally by the biotic filter. Given this low resilience, we tested several restoration techniques applied at large-scale within the Cossure rehabilitation project: nurse species seeding, topsoil removal, hay transfer and soil transfer. In order to assess the efficiency of restoration techniques we developed indices to measure the community structure integrity, disentangling lower and higher abundances compared to the reference. The best results were obtained with soil transfer, followed by topsoil removal, then nurse species seeding and finally hay transfer. The research conducted for this thesis shows that current knowledge in ecological restoration makes it possible to restore at least partially some La Crau ecosystem components, but ought to lead us to understand the importance of in situ conservation of natural habitats as a better alternative to restore them after they were destroyed
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Nieftagodien, Mohamed Noor. "The making of apartheid in Springs : group areas and forced removals." Thesis, 1995. https://hdl.handle.net/10539/25228.
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Prinsloo, Alwyn Petrus. "A critical analysis of the LRAD sub-programme in the Gauteng Province of South Africa." Diss., 2009. http://hdl.handle.net/2263/27144.
Full textAbstract:
Land ownership in South Africa has long been a source of conflict. The history of forced removals and a racially skewed distribution of land resources have left the new government, which took over in 1994, with a complex and difficult legacy. The new government has developed a land reform programme with three major elements to address the situation of landlessness, tenure insecurity and poverty among black people. The three major elements can be defined as follows: - The redistribution of land to the disadvantaged and poor for productive and residential purposes;
- Land restitution, which covers restitution of land to those who had been forcefully removed from land after 1913 as a result of racially discriminatory laws and practices and
- Tenure reform to those whose tenure of land is legally insecure.
Dissertation (MInst Agrar)--University of Pretoria, 2009.
Agricultural Economics, Extension and Rural Development
unrestricted
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Ntsimane, Radikobo Phillip. "The Lutheran churches' response to the forced removals in the western Transvaal and Bophuthatswana (1968-1984)." Thesis, 1999. http://hdl.handle.net/10413/4478.
Full textAbstract:
This thesis is about the Lutheran Churches' response to the forced removals which took place between 1968 and 1984 in Western Transvaal. Bills aimed at expropriating land from African people were passed through parliament from 1913 to 1984. These apartheid laws culminated in the fonnation of Bantustans where people of different nationalities among blacks were moved to. Among the Tswanas four villages in the Western Transvaal viz. Matlwang, Ga-Maloka, Botshabelo and Mogopa were moved between 1968 and 1984. The Lutheran Churches which were working in the four villages did not do much to help their members in time great need and distress. The villagers interviewed unanymously agreed that the Lutheran churches were silent during the time of the forced removals. The Lutheran churches in the world have a history of silence with regard to governments' unjust policies towards the people. Theologians and church leaders of the Evangelical Lutheran Church in Southern Africa (ELCSA) and its supporting mission society, the Rermannsburg Mission Society (HMS), the
Lutheran Church in Southern Africa (LCSA) and its supporting mission society, the Lutheran Church Mission, agree that the doctrine of the Two Kingdoms was not responsible for the silence of the Lutheran Churches in South Africa. The Lutheran Churches have an opportunity to make up for their past mistakes by initiating and joining existing projects aimed at helping the marginalised communities of South Africa. Among other pressing needs in South Africa besides the preaching of the gospel one can count landlessness, unemployment, homelessness, poverty, hunger, diseases like HIV/AIDS, and counselling of the abused individuals in both in the urban and the rural areas to which those who were forcefully removed are returning. This work is presented to churches in general and to the Lutheran Churches in particular so that they can preach the gospel of Jesus Christ in a wholistic rather than a narrow way. Jesus was
concerned about the poor, the captives, the blind, the sinners, the rulers and the oppressed.Thesis (M.Th.)-University of Natal, Pietermaritzburg, 1999.
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Molokoe, Benjamin Kenalemang Matshidiso. "A historical study of the Bakwena ba Mogopa as victims of forced removals, 1983-1994 / Benjamin Kenalemang Matshidiso Molokoe." Thesis, 1998. http://hdl.handle.net/10394/14085.
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Sambumbu, Sipokazi. "Social history, public history and the politics of memory in re-making âNdabeniââs pasts." Thesis, 2010. http://etd.uwc.ac.za/index.php?module=etd&action=viewtitle&id=gen8Srv25Nme4_2045_1305012450.
Full textAbstract:
It has been over a century since African people were forcibly removed by official decree in 1901, from the Cape Town dockland barracks and District Six, to Uitvlugt, a farm where a location of corrugated iron &lsquo
huts&rsquo
had just been constructed. This occurrence followed an outbreak of a bubonic plague in Cape Town in 1901, which became predominant among the Africans who worked at the docks, and who were in direct and constant contact with the main carriers of the disease, i.e., the rats coming out of ships from Europe. The outbreak resulted in African being stigmatised as diseased, and being banished to the outskirts of the city. Since then, knowledge about this historical occurrence has been continuously produced, presented and communicated in many ways. It has featured in many representations through memory, heritage and history.In 1902, the new residents of Uitvlugt gave the location the name kwa-Ndabeni. Ndabeni was a nickname that the residents had given to Walter Stanford who had chaired the commission that recommended for the establishment of the location in 1901. The prefix kwa- was added to the name so that it meant in Xhosa language, the place of Ndabeni. In that way, the residents, who at that time did not consider the location as a potential place of their permanent abode, named it in a way that disassociated them from the place.
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Tahboula, Rigobert R. "Implementation in a policy networks setting : a case study of the Association for Rural Advancement's Implementation of the Farm Dwellers' Project from 1994 until today." Thesis, 2010. http://hdl.handle.net/10413/4151.
Full textAbstract:
This research focuses on policy networks as a framework to analyse the implementation of the South African Land Reform (Labour Tenant) Act 3 of 1996 (LTA) and the Extension of Security of Tenure Act 62 of 1997 (ESTA) more generally. In particular, this research looks at the Association for Rural Advancement’s (AFRA) implementation of the farm dwellers project, specifically, how this organisation has been using the policy networks approach to implement its farm dwellers project. The LTA and the ESTA guide the South African post-apartheid land reform programme. This programme responds to the racially-based system of land access created by colonialism and apartheid. It is against this system of land access that the post-apartheid, democratic government undertook a vast land reform programme, intended to redress the injustices of the past (Drimie 2003:39). The LTA and ESTA are situated within this perspective and their objectives were derived from an understanding that land reform has the potential to make a direct impact on poverty through targeted resource transfers and by addressing the economic and social injustices caused by colonial and apartheid dispossession. However, after sixteen years of democracy and policy implementation of the land reform programme, little progress has been made. This includes an undertaking in the Reconstruction and Development Programme (RDP) of 1994, which provided a set of guidelines and principles for the evolving land policy, to redistribute, by 2014 (extended from 1999), 30% of the 80% of commercial farmland (mostly white owned) to black South Africans and to make land reform the driving force of rural development (Drimie 2003:39). By March 2009, a total of 5.2% of the targeted 30% of commercial farmland has been transferred through the various land reform programmes (Kleinbooi 2009:1). Concerns have been raised that attribute this seeming failure of the land reform programme to the government’s market approach (Mkhize 2004). This has been sustained by the government’s shift from the RDP to Growth, Employment and Redistribution (GEAR). AFRA, in its funding proposal of 1998-2000, has identified this shift as “disturbing because it implies that government’s economic and political direction is likely to result in reduced resources for rural and agricultural development, a shift which will impact hard on the already tough conditions of poverty that people live in.”
From this understanding, this research hopes to establish that the seeming failure of the implementation of the South African land reform can be improved through a more effective utilisation of policy networks. More particularly, this research hopes to establish how AFRA has been using policy networks to implement its Farm Dwellers project from 1994 until today.Thesis (M.Soc.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2010.
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Shiba, Thando Monica. "Social control in the 20th century and its impact on households: A case study of disarticulation from Sophiatown to Meadowlands, Soweto." Diss., 2021. http://hdl.handle.net/10500/27716.
Full textAbstract:
In South Africa, racial discrimination was witnessed through renowned segregationist acts including the Group Areas Act (No:41) of 1950, which forcibly displaced families from their homes and triggered significant social upheavals and the callous disintegration of long-established communities such as Sophiatown. The removals were a political strategy to relocate so-called “non-white” people from the inner city to townships such as Meadowlands explicitly chosen for their hazardous impure land known as mine dumps (Rodgers 1980:76). These displacements had a paradox of intergenerational homelessness triggered by instrumental racism that influenced politics of space and in effect, the disarticulation of the lives of black South Africans (Milgroom and Ribotc 2019:184). Therefore, it is important to undertake a study investigating the circumstances that gave rise to these forced removals, the subsequent breakdown of social order, a typical consequence of population relocation, which merits an examination of the contemporary implications and ramifications of disarticulation and highlights, in this regard, some significant shortcomings in post-Apartheid governance.Anthropology and Archaeology
M.A. (Anthropology)
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Lacoste, Guy Michel. "Joint loads in the presence of chin cup forces." 1995. http://catalog.hathitrust.org/api/volumes/oclc/46960475.html.
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Alotaibi, Mohammed Badri. "Characteristics and removal of filter cake formed by formate-based drilling mud." 2008. http://hdl.handle.net/1969.1/ETD-TAMU-2800.
Full textAbstract:
Formate-based mud has been used to drill deep gas wells in Saudi Arabia since 2004.
This mud typically contains XC-polymer, starch, polyanionic cellulose, and a relatively
small amount of calcium carbonate particles, and is used to drill a deep sandstone
reservoir (310°F). Calcium carbonate particles are frequently used as weighting material
to maintain the pressure that is required for well control and minimize the leak-off. Such
solids become consolidated and trapped in the polymeric material and this makes the
filter cake a strong permeability barrier.
Various cleaning fluids were proposed to remove drilling mud filter cake;
including: solid-free formate brine and formate brine doped with organic acids (acetic,
formic, and citric acids), esters, and enzymes. The main objective of this research is to
assess the effectiveness of these cleaning fluids in removing drilling mud filter cake. A
dynamic high-pressure/high-temperature (HPHT) cell was used to determine
characteristics of the drilling mud filter cake. Drilling mud and completion fluids were
obtained from the field. Compatibility tests between potassium formate brine, cleaning fluids, and formation brine were performed at 300ºF and 200 psi using HPHT visual
cells. Surface tensions of various cleaning fluids were also measured at high
temperatures.
The conventional method for cleaning the filter cake is by circulating solid-free
formate brines at a high flow rate. This mechanical technique removes only the external
drilling fluid damage. Citric acid at 10 wt%, formic acid, and lactic acid were found to
be incompatible with formate brine at room temperature. However, these acids were
compatible with formate brine at temperatures greater than 122°F. Only acetic acid was
compatible with formate brine. A formula was developed that is compatible at room and
reservoir temperature. This formula was effective in removing filter cake. A corrosion
inhibitor was added to protect downhole tubulars. In general detail, this research will
discuss the development of this formula and all tests that led to its development.
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Murrell, Elbert Frederick. "Vascular changes in the periodontal ligament following the removal of orthodontic forces." 1992. http://hdl.handle.net/1993/17463.
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HUNG, CHUNG HSIUNG, and 洪崇雄. "INVESTIGATION OF METAL TURNINIG-REMOVAL Cr-Mo ALLOY STEEL CONSIDERING MACHINED SURFACE ROUGHNESS AND CUTTING FORCE." Thesis, 1997. http://ndltd.ncl.edu.tw/handle/77975864992146924578.
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Lin, Chih-Kuang, and 林志光. "Constant Milling Force in High Speed and Constant Metal Removal Rate Operation Via Grey Fuzzy Controller System." Thesis, 1996. http://ndltd.ncl.edu.tw/handle/39531475562245340338.
Full textAbstract:
碩士大同工學院
機械工程學系
84
In this study, a grey fuzzy controller (GFC) is developed to implement constant metal removal rate (MRR) on the constant milling force (CMF) in highspeed. The controller can automatically adjust the spindle speed to maintain the MRR at the desired stable value. The desired quality of workpiece, such as surface roughness and milling force, is due to the optimal values come from theexperiments. The fuzzy control techniques and the grey theory are combined todevelop a grey fuzzy controller (GFC) to the constant milling operation. GreyGrey model is a good predictor with high accurate forecasting ability.Fuzzy controlis effective for the control system with uncertain plantparameters. For thecomplex phenomenon of the high speed machining process,a experiment methodis adopted to find the force model describing the milling behavior. In thisexperiment, responce surface methodology (RSM) was used. In order to get thebetter machining quality, surface roughness model (Ra) was also acquired. Themodel is acceptable due to the variance results. In the allowable surfaceroughness levels, the relations between feedrate and cutting depth are obtainedFinally, grey fuzzy control system was applied to achieve constant MRR and CMF operation. Simulation result show that GFC system can easily achieve the desiredMRR and constant milling force under vary cutting condition.
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Tung, Liu Pak, and 廖柏東. "Influence of Down Force, Rotation Speed and Slurry flow rate on Removal Rate and Uniformity of Tungsten by Chemical Mechanical Polish process." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/13057658970950780375.
Full textAbstract:
碩士國立交通大學
工學院碩士在職專班半導體材料與製程設備學
94
Abstract In the deep-submicro semiconductor manufacturing, such as less then 0.5 mm devices design rule and more than three layer of interconnects, more severe the depth of focus budget of optical lithography techniques, all of these requirement need a globe planarization technique. Chemical mechanical polishing, CMP, is the only way known to achieve the globe planarization. In this experiment, the effects of Down Force and Rotation Speed on improvement of Removal Rate and Non-Uniformity are examined. The results presented distinctly suggest that the wafer Removal Rate and Non-Uniformity can be improved by increasing the wafer Down Force at certain range. Besides, the wafer Rotation Speed is also influences the process result. An attempt is made here to search for the optimal condition for the wafer Removal Rate and Non-Uniformity subjected to the constraints of the present experiment system. In this search wafer Down Force is tested at 5 psi and wafer Rotation Speed tested at 360 rpm, the wafer Removal Rate can be conclude 5000A and wafer Non-Uniformity can be descend to about 8% - 8.2%.
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Erfurth-Jach, Teresa Friederike. "Biomechanische Untersuchungen an thermoplastisch geformten Schienen." Doctoral thesis, 2012. http://hdl.handle.net/11858/00-1735-0000-000D-EFD6-0.
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Engelke, Benjamin. "Kraft- und Drehmomentabgabe thermoplastisch geformter Schienen bei Frontzahnderotation vor und nach Alterungssimulation." Doctoral thesis, 2010. http://hdl.handle.net/11858/00-1735-0000-0006-B146-4.
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