Tesis sobre el tema "Artificial and natural clay"
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1
Lahiri, Tapesh. "Characterisation of the soils of the Eastern Himalayan region together with an attempt of the separation of components of artificial and natural clay mixtures". Thesis, University of North Bengal, 1989. http://hdl.handle.net/123456789/849.
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Leal, Ana Maria. "Conditioning of Manila clam broodstock on natural and artificial diets". Thesis, Bangor University, 1994. https://research.bangor.ac.uk/portal/en/theses/conditioning-of-manila-clam-broodstock-on-natural-and-artificial-diets(0ec43f18-fa32-4d46-9dab-e8e7ea2979ee).html.
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Two trials in 1991 and another two in 1992 were carried out on the broodstock conditioning of Manila clams, Tapes philippinarum. The main objective was to manipulate the lipid and polyunsaturated fatty acid content of Manila clam eggs by maintaining broodstock in different dietary regimes. The second objective was to assess dried algae as alternative diets for conditioning broodstock. Clams were brought into the laboratory from the natural environment early in the year, before gametogenesis had started. Supplements of cultured live (Dunaliella tertiolecta, Skeletonema costatum, Tetraselmis suecica and Isochrysis galbana) and dried algae (T. suecica) diets were fed to the broodstock, usually in a range of mixed diets, at rations equivalent to 3% or 6% of the initial dry meat weight of the broodstock in dry weight of algae per day. The microalgae differed in their long-chain polyunsaturated fatty acid content (PUFA). Unfed control clams received only the organic material which remained in the sea water after sand filtration. The nutritional value of these diets in relation to gametogenesis, fecundity, quality of eggs, and viability and growth of larvae were assessed. Dry T. suecica was the same food value as live T. suecica but Manila clams produced more eggs if supplements of live algae were added. The requirement for conditioning Manila clams (32 mm shell length) to spawn with live or dry T. suecica+S. costatum was 500 to 700 "day-degrees" (D°). With dry T. suecica on its own or mixed with I. galbana, S. costatum and D. tertiolecta it was 500 to 600 Do (44 mm shell length). In one trial clams spawned in the tanks (equivalent to 462 Do) before the first attempt to spawn them was made. Successful spawning was dependent on the quantity and quality of the algal diet during gametogenesis. With a 6% food ration, clams fed dry T. suecica+S. costatum or dry T. suecica+l. galbana produced the highest number of eggs (an average of 3.2 and 4.5 million eggs per female, respectively). The average fecundity was 83% lower when the diet was reduced to a 3% food ration. The dry meat weight, condition index and fecundity of fed broodstock were significantly higher than for unfed animals. The quantity of lipid in the eggs, usually between 4 and 9 ng egg-1, was similar whatever the broodstock diet. However, levels of the essential polyunsaturated fatty acids 20: 5w3 and 22: 6w3 in the eggs were low if the broodstock diet was deficient in these PUFAs. Even though diet manipulation caused changes in the fatty acid composition of the eggs, growth and survival of Manila clam larvae was not reduced in a hatchery situation.
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Le, Truong Khanh Duy. "Time Dependent Behaviour of Naturally and Artificially Structured Clays". Thesis, The University of Sydney, 2018. http://hdl.handle.net/2123/20866.
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Recent studies on the time dependent behaviour of geotechnical structures have highlighted the need for careful consideration of a number of natural soil characteristics such as anisotropy, structure and strain rate dependency. Increased emphasis of the accurate prediction of structural deformations has placed further importance on correctly interpreting these soil characteristics. Yet, it appears that despite detailed ground investigations and laboratory sties, inadequate predictions of ground movements are still encountered. This has resulted in the need for a careful revision of the general time-dependent properties of structured materials. This research aimed to find a framework for understanding the various time-dependent phenomena. High quality samples from Ballina, N.S.W., Australia and Hyde Park, London, United Kingdom, and one artificially cemented material, a gypsum--kaolin mixture, were tested in their intact, remoulded and reconstituted states using oedometer and advanced triaxial apparatus. The structure and nature of the clays from the different origins were investigated microscopically and correlated with its large and small strain mechanical response. The research program investigated effects of soil structuration, strain-rate and stress-rate on the measured geotechnical properties. The evolution of plastic strains along defined stress paths were also studied in order to investigate creep behaviour in stress space. The time-dependent behaviour of structured and structureless soils was found to be consistent and were predictable under the same framework. The capabilities of a number of existing time-dependent models were investigated in capturing the viscous behaviour observed. It was found that while a number of models were able to capture some of the time effects, there is a need for (i) the inclusion of rate effects within the standard yield surface, (ii) modelling of stress ratio degradation following peak strength and (iii) a new approach to modelling the plastic strain component during creep.
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Nishimura, Satoshi. "Laboratory study on anisotropy of natural London clay". Thesis, Imperial College London, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.423085.
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Lentini, Roberta. "Integrating artificial with natural cells". Doctoral thesis, Università degli studi di Trento, 2015. https://hdl.handle.net/11572/369102.
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Previous attempts to control cellular behavior were mainly based on genetic engineering. While useful, such an approach suffers from several complications. Living cells grow and evolve which could lead to modifications of the engineered circuits, causing not only the loss of their functions but also an altering of the environment. However, other methods are possible. All living cells can naturally sense and respond to their environment and to each other. Thus, artificial, non- living cells can be engineered to activate already existing natural cellular pathways. In this way, the genetic engineering component moves from the natural to completely artificial, laboratory-made cells. Moreover, synthetic systems operating in living organisms also depend on elements with unknown function, leaving many gaps in the understanding of how living cells work. Building life- like systems with non-living components could help reveal unrecognized but necessary cellular mechanisms. However, the design of functional, genetically encoded cell-free systems is difficult, because biological parts have been evolved to function optimally inside of living cells. In vitro conditions are different.
First, some practical rules for the construction of functional synthetic circuits in vitro were defined. The Influences of the organization of genetic elements within a synthetic operon on protein expression levels were studied and optimal sequence compositions and lengths between genes to assemble genetic circuits were found. Then, artificial cells that can control the behavior of living systems were built. The artificial cells were able to sense a molecule that Escherichia coli cannot sense on its own and translate that molecule into a chemical message that E. coli can sense and respond to. The natural sensing of E. coli was expanded without genetically modifying the bacteria. Finally, to better integrate artificial with natural cells, a complete communication pathway was constructed. Bacteria speak to each other by quorum sensing. Such mechanisms mediate cell-cell communication among bacteria and regulate several cell density related processes, such as virulence. Various synthetic quorum sensing mechanisms were constructed in vitro within artificial cells. Artificial cells able to sense the presence of living cells were built. In addition, the artificial cells were capable to synthesize quorum sensing molecules for E. coli, Vibrio harveyi, Vibrio fischeri and Pseudomonas aeruginosa. When integrated together, artificial cells successfully mediated interspecies communication with natural cells. Such artificial systems could be useful as therapeutic tools to defeat pathogenic infections. Moreover, the achievement of such functions represents a new way to better understand the potential of the artificial cells to mimic cellular life.
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Lentini, Roberta. "Integrating artificial with natural cells". Doctoral thesis, University of Trento, 2015. http://eprints-phd.biblio.unitn.it/1549/1/Lentini_Roberta_PhD_thesis.pdf.
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Previous attempts to control cellular behavior were mainly based on genetic engineering. While useful, such an approach suffers from several complications. Living cells grow and evolve which could lead to modifications of the engineered circuits, causing not only the loss of their functions but also an altering of the environment. However, other methods are possible. All living cells can naturally sense and respond to their environment and to each other. Thus, artificial, non- living cells can be engineered to activate already existing natural cellular pathways. In this way, the genetic engineering component moves from the natural to completely artificial, laboratory-made cells. Moreover, synthetic systems operating in living organisms also depend on elements with unknown function, leaving many gaps in the understanding of how living cells work. Building life- like systems with non-living components could help reveal unrecognized but necessary cellular mechanisms. However, the design of functional, genetically encoded cell-free systems is difficult, because biological parts have been evolved to function optimally inside of living cells. In vitro conditions are different.
First, some practical rules for the construction of functional synthetic circuits in vitro were defined. The Influences of the organization of genetic elements within a synthetic operon on protein expression levels were studied and optimal sequence compositions and lengths between genes to assemble genetic circuits were found. Then, artificial cells that can control the behavior of living systems were built. The artificial cells were able to sense a molecule that Escherichia coli cannot sense on its own and translate that molecule into a chemical message that E. coli can sense and respond to. The natural sensing of E. coli was expanded without genetically modifying the bacteria. Finally, to better integrate artificial with natural cells, a complete communication pathway was constructed. Bacteria speak to each other by quorum sensing. Such mechanisms mediate cell-cell communication among bacteria and regulate several cell density related processes, such as virulence. Various synthetic quorum sensing mechanisms were constructed in vitro within artificial cells. Artificial cells able to sense the presence of living cells were built. In addition, the artificial cells were capable to synthesize quorum sensing molecules for E. coli, Vibrio harveyi, Vibrio fischeri and Pseudomonas aeruginosa. When integrated together, artificial cells successfully mediated interspecies communication with natural cells. Such artificial systems could be useful as therapeutic tools to defeat pathogenic infections. Moreover, the achievement of such functions represents a new way to better understand the potential of the artificial cells to mimic cellular life.
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Zhang, Li. "Clay Minerals Supporting Microbial Metabolic Activities in Natural Sediments". Miami University / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=miami1564142598119446.
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Armstrong, Holly. "Natural Flow". VCU Scholars Compass, 2006. http://scholarscompass.vcu.edu/etd/694.
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Nature never ceases to amaze me with momentary observations of fluid energy: the purposeful curvature of a blue heron's neck; the pattern of water as it sweeps across a rock sculpted by that very motion; the changing light and shadows created as wind blows through tall grasses. The spark of beauty in these moments lies in the energy that causes this constant change. To capture this energy, either potential or kinetic, and embody it through textures and flow of mass, is my essential goal as an artist.
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Bruno, Odemir Martinez. "Paralelismo em visão natural e artificial". Universidade de São Paulo, 2000. http://www.teses.usp.br/teses/disponiveis/76/76132/tde-26052014-161557/.
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Nesta tese são abordados, de maneira integrada, aspectos de paralelismo em visão natural e artificial, com discussões críticas das diversas áreas relacionadas. O paralelismo é discutido no sistema visual dos primatas, assim como suas principais contribuições e motivações incentivando a incorporação de paralelismo em sistemas de visão artificial. Um dos objetivos principais é fornecer as bases de paralelismo para o desenvolvimento do projeto Cyvis-1, uma proposta do Grupo de Pesquisa em Visão Cibernética (IFSC-USP) para visão versátil, com forte motivação biológica e baseada no córtex visual dos primatas. Para tanto, foi introduzida e implementada a proposta CVMP (Cybernetic Vision Message Passage), um conjunto de ferramentas para o desenvolvimento de aplicações paralelas em visão, tanto para sistemas distribuídos como para máquinas multiprocessadores. Baseada em programação orientada a objetos, interação homem-máquina, engenharia de software e programação visual, a proposta prima pelo desenvolvimento de forma simples e amigável. O CVMP é testado, avaliado e validado quanto a aspectos de funcionalidade e utilização, através da implementação paralela de diversos algoritmos de visão computacional e de processamento de imagens (operadores locais, transformada de Hough e transformada de Fourier, entre outros) os quais, além de ilustrar a utilização da ferramenta, são discutidos em termos de arquitetura e balanceamento de carga. São apresentadas três aplicações reais de sistemas paralelos de visão computacional, implementadas através do CVMP, demonstrando a eficiência da ferramenta, na implementação paralela, na utilização e cooperação de trabalho. Duas destas aplicações (integração de atributos visuais no projeto Cyvis-1 e um modelo de complexidade com base na percepção humana), foram desenvolvidas em conjunto com outros pesquisadores do Grupo de Pesquisa em Visão Cibernética. A terceira aplicação apresenta uma proposta do autor para um sistema automático de reconhecimento de plantas arbóreas (Botânica)This thesis addresses, in an integrated way, the concept and usage of parallelism in natural and artificial vision. It starts by revising the primate visual system, and discussing how its principles and solutions can be extended to computational systems. One of the main objectives is to supply the parallelism backbone for the development of the Cyvis-1 System, which is a proposal of the Cybernetic Vision Research Group (IFSC-USP) for versatile vision, presenting a strong biological motivation, especially regarding the primate visual cortex. In order to achieve these objectives, the CVMP - Cybernetic Vision Message Passage - had to be developed, representing a set of simple and friendly parallel tools for computer vision applications in distributed and parallel (multiprocessor) systems, which is based on object oriented programming, human-machine interaction, software engineering and visual programming. The CVMP is tested, evaluated and validated with respect to functionality and utilization through the parallel implementation of several algorithms in computer vision and image processing (local operators, Hough transform, Fourier transform, etc.) which, in addition to illustrating the tools, are also discussed as far as their architecture and load balancing is concerned. Three applications of parallel computer vision systems to real situations are presented and implemented by using CVMP, corroborating the effectiveness of the tools in the parallel implementation, usage, and researcher integration. Two such applications (visual attributes integration in Cyvis-1 and a human complexity model) have been developed in collaboration with other researchers at the Cybernetic Vision Research Group. The third application presents the author\'s proposal for an automated system for arboreal plants recognition (Botany)
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Mirzakulova, Ekaterina Viktorovna. "Natural and Artificial Flavin-Based Catalysis". Bowling Green State University / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1371415783.
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Vick, Jeffrey A. "Natural Selection". VCU Scholars Compass, 2006. http://scholarscompass.vcu.edu/etd/1254.
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My thesis work is about imagination. I use the collaborative efforts of the viewer's mind and my sculptures, or specimens, to make associations of real life animals. I feel this engages the viewer and in turn invites them to inspect the work on closer level. This is my ultimate goal in the work, to take hold of the viewer's curiosity and have them examine the work on a closer level.
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Lindblom, Jessica. "Social Situatedness of Natural and Artificial Intelligence". Thesis, University of Skövde, Department of Computer Science, 2001. http://urn.kb.se/resolve?urn=urn:nbn:se:his:diva-626.
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The situated approach in cognitive science and artificial intelligence (AI) has argued since the mid-1980s that intelligent behaviour emerges as a result of a close coupling between agent and environment. Lately, many researchers have emphasized that in addition to the physical environment, the social environment must not be neglected. In this thesis we will focus on the nature of social situatedness, and the aim of this dissertation is to investigate its role and relevance for natural and artificial intelligence.
This thesis brings together work from separate areas, presenting different perspectives on the role and mechanisms social situatedness. More specifically, we will analyse Vygotsky's cognitive development theory, studies of primate (and avian) intelligence, and last, but not least, work in contemporary socially situated AI. These, at a first glance, quite different fields have a lot in common since they particularly stress the importance of social embeddedness for the development of individual intelligence.
Combining these separate perspectives, we analyse the remaining differences between natural and artificial social situatedness. Our conclusion is that contemporary socially artificial intelligence research, although heavily inspired by empirical findings in human infants, tends to lack the developmental dimension of situatedness. Further we discuss some implications for research in cognitive science and AI.
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Young, Rupert. "Visual control in natural and artificial systems". Thesis, University of Surrey, 2000. http://epubs.surrey.ac.uk/843083/.
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The desire to produce artificial vision systems which behave in an intelligent, humanlike way or which can autonomously and automatically perform tasks currently only performed by humans has been a goal of Artificial Intelligence research for many decades. Until recently much of the research concentrated on extracting visual representations of objects from single, static scenes. The last decade has seen an increase in interest concerning mobile robotics for navigation, planning and autonomous control as well as for the interpretation of events in real, dynamic scenes. Presented in this thesis is research on artificial vision systems from two different, but both necessary, standpoints. One concerns low-level vision-based behaviour of object tracking based upon a naturalistic theory of perception and behaviour within living systems. The other takes a more application and engineering based approach and its goal is to address high-level scene interpretation and control of processing resources. Numerous experiments are presented to demonstrate the various issues. The two main experiments, corresponding to the two research streams, are a system which is able to fixate complex multi-coloured objects and a fully integrated vision system for predicting and following, with a mobile sensor, events in a dynamic scene.
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Voznytsia, Anastasiia. "Operational objectives of natural and artificial systems". Thesis, National Aviation University, 2021. https://er.nau.edu.ua/handle/NAU/50990.
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1. Aziz, Abd El; Rasha Fady (2013). "Business Improvement using Organisational Goals, Riva Technique and e-Business Development Stages". Journal of Enterprise Information Management.
2. "Difference Between Strategic & Operational Objectives". Small Business. Retrieved November 2015. Check date values in: |access-date= (help) Hoang, Paul (2007). "Unit 1.3." Business & Management. IBID. pp. 40–51.
3. Harel, David. (2014). Algorithmics The Spirit of Computing. Springer Berlin. ISBN 978-3-642-44135-6. OCLC 876384882.
4. Schaeffer J. (2009) Didn't Samuel Solve That Game?. In: One Jump Ahead. Springer, Boston, MAThe work is devoted to the review and analysis of goals of natural and artificial systems functioning. The state of the system is usually referred to as several properties of the basic ones, which the system manages at a certain period of time. The fundamental property of systems is their stability, i.e. the ability of the system to withstand external influences. Life expectancy of the system depends on it.
Робота присвячена огляду та аналізу цілей функціонування природних та штучних систем. Стан системи зазвичай називають декількома властивостями основних, якими система управляє протягом певного періоду часу. Основною властивістю систем є їх стабільність, тобто здатність системи протистояти зовнішнім впливам. Від цього залежить тривалість життя системи.
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Akar, Dilek Shahwan Talal. "Physicochemical characterization of the sorption behavior of Cs+ and Sr2+ Ions on natural kaolinite and cliptilolite minerals/". [s.l.]: [s.n.], 2005. http://library.iyte.edu.tr/tezler/master/kimya/T000489.pd.
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Rooj, Sandip. "Reinforcement of Natural Rubber by “Expanded Clay” Adopting “Propping-Open Approach”". Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2013. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-129370.
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During the last years rubber nanocomposites obtained by incorporating anisotropic clay nanoparticles within a rubber matrix to tailor material properties have attracted steadily growing interest. However, one main complication preventing rubber-clay nanocomposites from many potential applications is the difficulty to achieve a high degree of exfoliation particularly in case of melt mixing or compounding (using mixing equipment like internal mixer, two roll mills which can be up-scaled in industry). Albeit commercially available organomodified montmorillonite clays (OMt) are fairly compatible with the polar rubber like Acrylo-nitrile butadiene rubber (NBR), carboxylated nitrile rubber (XNBR), chloroprene rubber (CR) etc., its dispersion in non-polar rubbers like natural rubber (NR), is rather unsatisfactory. Incorporation of only 5 phr of OMt in NR by mechanical mixing leads to very poor dispersions with larger aggregates. Large agglomerates of OMt were observed with bare eyes throughout the matrix. Even in the TEM micrographs, highly agglomerated structures of clay particle were observed. A high degree of exfoliation of such clay is achieved in NR utilizing the so called ‘Propping-open approach’ where stepwise expansion of interlayer spacing of Mt took place. A series of long chain fatty acids (C16-C22) are intercalated into the interlayer space of OMt and a gradual expansion of the interlayer space were observed as the chain length of the fatty acid increased. Wide angle X-ray diffraction (WAXD), Fourier transform infrared spectroscopy (FTIR) and contact angle measurement indicated successful intercalation of the fatty acids into the interlayer space of the clay minerals. Since the fatty acid containing 22 carbon atoms has the largest interlayer distance among the modified samples studied, it has been selected for further study to understand the reinforcing behavior in NR matrix. An unusual mechanical percolation behavior of EOMt nanoparticles was observed in a NR matrix. The value of the mechanical percolation threshold (φp) and the fractal nature of nanoparticle clusters were determined through an analysis of the experimental data based on a theory put forward by Huber and Vilgis. This phenomenon was discussed in terms of fractal dimensions of the nanoparticle cluster. The impact of filler dispersion and rubber-filler interactions on the viscoelastic behavior of NR nanocomposites was systematically investigated. Significant non-linear viscoelastic behavior (Payne effect) was observed at very low EOMt content. Kraus and Maier-Göritz models were utilized to interpret such non-linear viscoelastic behavior. The nanocomposites showed enormous improvement in different physic-mechanical properties in the presence of EOMt. Technical elastomers are generally filled with certain fillers (e.g. carbon black) in order to reinforce the rubber matrix for some typical applications like tires, conveyer belts etc. Such rubber goods are always exposed to cyclic stress and deformations attributed to their dynamic application. Under constant and repeated applied stress, cracks develop at a stress concentration point, which could lead to ultimate failure. Therefore, the crack initiation and propagation behavior in such rubber products is very fundamental and need proper attention. The role of EOMt nanoparticles on the microstructure and fracture mechanical behavior of CB filled NR composites was investigated. Using pure-shear test specimen tear fatigue analysis (TFA) tests under cyclic conditions were carried out to explicate the crack growth behavior of CB filled NR in the presence of EOMt. A significant reduction in crack growth rate was noticed in the presence of only 5 phr of EOMt. Furthermore, instrumented tensile-impact tests (IT-IT) were also performed for the characterization of the crack resistance of the materials under impact-like loading conditionsDie Einarbeitung von nur 5 phr organisch modifizierten Montmorillonite (OMt) in Naturkautschuk (NR) durch mechanisches Mischen führt zu einer sehr schlechten Verteilung mit größeren Aggregaten. Große Agglomerate von OMt waren mit bloßem Auge in der NR Matrix sichtbar. Sogar in TEM Aufnahmen wurden stark agglomerierte Strukturen beobachtet. Ein hoher Grad der Exfolierung von diesem Clay in NR wird durch die Nutzung des so genannten ‘Propping-open’ Ansatzes erreicht, in dem eine stufenweise Aufweitung des Zwischenschichtabstandes des OMt stattfindet. Eine Reihe langkettiger Fettsäuren (C16 – C22) wurde in die Zwischenschicht des OMt eingefügt. Mit zunehmender Kettenlänge der Fettsäuren wurde eine allmähliche Aufweitung der Zwischenschicht beobachtet. Da OMt, der mit einer Fettsäure mit 22 Kohlenstoffatomen modifiziert wurde, den größten Zwischenschichtabstand aller untersuchten Proben hatte, wurde diese Fettsäure für die weiteren Untersuchungen ausgewählt, um das Verstärkungsverhalten in der NR Matrix zu verstehen. Ein ungewöhliches Perkolationsverhalten der expandierten OMt (EOMt) Nanopartikel wurde in einer NR Matrix beobachtet. Der Wert der mechanischen Perkolationsschwelle (φp) und die fraktale Natur der Nanopartikel Cluster wurden durch eine Analyse der experimentellen Daten bestimmt, wobei eine Theorie, die von Huber und Vilgis vorangetrieben wurde, zur Anwendung kam. Dieses Phänomen wurde in Bezug auf die fraktalen Dimensionen der Nanopartikel Cluster diskutiert. Die Einfluss von EOMt Nanopartikel auf die Mikrostruktur und das mechanische Bruchverhalten von russgefüllten NR Kompositen wurde untersucht. Unter Verwendung reiner Schertestproben wurden Rissermüdungsanalysen unter zyklischer Belastung ausgeführt, um das Risswachstumsverhalten von russgefülltem NR in der Gegenwart von EOMt zu untersuchen und zu erklären. Eine signifikante Reduktion der Rissausbreitungsrate wurde in Gegenwart von nur 5 phr EOMt erreicht. Des Weiteren wurden auch instrumentierte Schlagzugprüfungen zur Charakterisierung des Risswiderstandes von Materialien unter schlagartigen Belastungsbedingungen durchgeführt
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Gu, Yingying y 顾莹莹. "Electrokinetic remediation of cadmium-contaminated natural clay of high buffer capacity". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2011. http://hub.hku.hk/bib/B46279015.
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Zhang, Yongcheng. "Part I. Natural fiber / thermoplastic composites Part II. Studies of organo-clay synthesis and clay intercalation by epoxy resins /". Diss., Mississippi State : Mississippi State University, 2008. http://library.msstate.edu/etd/show.asp?etd=etd-11032008-094748.
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Pires, André Rama. "A evidência do natural". Master's thesis, Universidade de Lisboa. Faculdade de Arquitetura, 2016. http://hdl.handle.net/10400.5/12661.
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Woolfson, Adrian. "Natural and artificial forms of human CD1 genes". Thesis, University of Cambridge, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.282946.
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Vasconcelos, Margarida Perloiro Morgadinho Pablo. "Densidade urbana entre o natural e o artificial". Master's thesis, Universidade de Lisboa, Faculdade de Arquitetura, 2017. http://hdl.handle.net/10400.5/14436.
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Koroidov, Sergey. "Water splitting in natural and artificial photosynthetic systems". Doctoral thesis, Umeå universitet, Kemiska institutionen, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-86363.
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Photosynthesis is the unique biological process that converts carbon dioxide into organic compounds, for example sugars, using the energy of sunlight. Thereby solar energy is converted into chemical energy. Nearly all life depends on this reaction, either directly, or indirectly as the ultimate source of their food. Oxygenic photosynthesis occurs in plants, algae and cyanobacteria. This process created the present level of oxygen in the atmosphere, which allowed the formation of higher life, since respiration allows extracting up to 15-times more energy from organic matter than anaerobic fermentation. Oxygenic photosynthesis uses as substrate for the ubiquitous water. The light-induced oxidation of water to molecular oxygen (O2), catalyzed by the Mn4CaO5 cluster associated with the photosystem II (PS II) complex, is thus one of the most important and wide spread chemical processes occurring in the biosphere. Understanding the mechanism of water-oxidation by the Mn4CaO5 cluster is one of today’s great challenges in science. It is believed that one can extract basic principles of catalyst design from the natural system that than can be applied to artificial systems. Such systems can be used in the future for the generation of fuel from sunlight. In this thesis the light-induced production of molecular oxygen and carbon dioxide (CO2) by PSII was observed by membrane-inlet mass spectrometry. By analyzing this observation is shown that CO2 not only is the substrate in photosynthesis for the production of sugars, but that it also regulates the efficiency of the initial steps of the electron transport chain of oxygenic photosynthesis by acting, in form of HCO3-, as acceptor for protons produced during water-splitting. This finding concludes the 50-years old search for the function of CO2/HCO3− in photosynthetic water oxidation. For understanding the mechanism of water oxidation it is crucial to resolve the structures of all oxidation states, including transient once, of the Mn4CaO5 cluster. With this application in mind a new illumination setup was developed and characterized that allowed to bring the Mn4CaO5 cluster of PSII microcrystals into known oxidation states while they flow through a narrow capillary. The optimized illumination conditions were employed at the X-ray free electron laser at the Linac Coherent Light Source (LCLS) to obtain simultaneous x-ray diffraction (XRD) and x-ray emission spectroscopy (XES) at room temperature. This two methods probe the overall protein structure and the electronic structure of the Mn4CaO5 cluster, respectively. Data are presented from both the dark state (S1) and the first illuminated state (S2) of PS II. This approach opens new directions for studying structural changes during the catalytic cycle of the Mn4CaO5 cluster, and for resolving the mechanism of O-O bond formation. In two other projects the mechanism of molecular oxygen formation by artificial water oxidation catalysts containing inexpensive and abundant elements were studied. Oxygen evolution catalyzed by calcium manganese and manganese only oxides was studied in 18O-enriched water. It was concluded that molecular oxygen is formed by entirely different pathways depending on what chemical oxidant was used. Only strong non-oxygen donating oxidants were found to support ‘true’ water-oxidation. For cobalt oxides a study was designed to understand the mechanistic details of how the O-O bond forms. The data demonstrate that O-O bond formation occurs by direct coupling between two terminal water-derived ligands. Moreover, by detailed theoretical modelling of the data the number of cobalt atoms per catalytic site was derived.
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Ingram, Peter James. "The application of numerical models to natural stiff clays". Thesis, City University London, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.340454.
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BRANDÃO, Yana Batista. "Tratamento Térmico Por Contato Direto (dictt) de Efluentes Líquidos Fenólicos Em Uma Planta Semi-industrial: Estudo Experimental e Modelagem do Processo Por Redes Neurais Artificiais". Universidade Federal de Pernambuco, 2012. https://repositorio.ufpe.br/handle/123456789/11936.
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Existe uma gama de processos que podem ser empregados no tratamento de compostos orgânicos tóxicos como o fenol presente em efluentes líquidos. Todavia, restrições como alto custo de instalação e tempo de contato relativamente longo devem ser levadas em consideração para a escolha do processo a ser utilizado. Uma nova técnica de tratamento de efluentes contaminados por compostos fenólicos, denominada de tratamento térmico por contato direto (Direct Contact Thermal Treatment - DiCTT), vem atraindo o interesse de vários grupos de pesquisa. O Departamento de Engenharia Química da UFPE possui um protótipo de planta experimental deste processo. O método DiCTT tem como atrativo principal a utilização do gás natural como fonte energética, a capacidade demonstrada de oxidar compostos fenólicos a baixas temperaturas e pressão atmosférica, e sua natureza em empregar uma configuração de reator muito compacta. Nesta pesquisa, foram avaliados os efeitos das variáveis operacionais: vazão de alimentação do efluente líquido, concentração inicial de fenol, a taxa de reciclagem dos gases de combustão, razão molar estequiométrica fenol/peróxido de hidrogênio, vazão do gás natural e excesso do ar. Após estudos preliminares, envolvendo duas etapas (Etapa 1 e Etapa 2) e dois modos operatórios do processo (MO1 e MO2), foi efetuado um planejamento experimental do tipo Delineamento Composto Central Rotacional com fatorial (k) de (23) considerando a taxa de evaporação da fase líquida (inferior à 12%) e a temperatura do efluente líquido (75-790C) (Etapa 3). Com os resultados obtidos, foi realizado um planejamento fatorial (k) completo de (32) para identificação das condições operacionais ótimas do processo, nas faixas de variação estudadas (Etapa 4). As análises envolveram a oxidação termoquímica do fenol e dos seus respectivos intermediários de degradação até a mineralização do composto orgânico e formação de ácidos, com monitoramento das concentrações de fenol e seus intermediários por Cromatografia em fase Líquida de Alta Eficiência, medições do teor de Carbono Orgânico Total com um analisador COT e do potencial hidrogeniônico, com um medidor de pH, respectivamente. Aplicando a superfície de respostas e curvas de contorno com uso do software Statistica versão 8.0, foram identificadas as condições ótimas, nos intervalos de variação estudados, para a degradação do fenol, até 100%, e a conversão de COT, até 40%: vazão de gás natural de 4 m3/h, excesso de ar de 10%, razão molar estequiométrica fenol/peróxido de hidrogênio de 75% e taxa de reciclagem dos gases de combustão de 100%, valores satisfatórios para a degradação do fenol, porém, necessita-se ainda de melhorar as taxas de mineralização. Na etapa final desta pesquisa, foi usada a modelagem via Redes Neurais Artificiais (RNAs), com o software Statistica 8.0 e o módulo “Neural Networks” para predizer os resultados experimentais da degradação do fenol, conversão do COT e da velocidade de degradação do fenol, em função do tempo. Com os resultados obtidos, possibilitou-se concluir que o modelo mais representativo é o Modelo de Regressão e a forma da rede é a Multi Layer Perceptron. Verifica-se ainda que as correlações observadas variaram entre 95,33% até 99,58%, indicando um modelo satisfatório na predição dos resultados experimentais.
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Aragão, Débora Martins. "Adsorção de Pb (II), Cd (II) E Cu (II) em argila caulinítica natural e argila natural contendo montmorilonita". Universidade Federal de Sergipe, 2012. https://ri.ufs.br/handle/riufs/6042.
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Coordenação de Aperfeiçoamento de Pessoal de Nível SuperiorThe contamination by toxic metals has been a serious environmental problem. Many researches have been developed with the objective the environmental remediation. The adsorption has been one of the most used process by researchers to remove metals in recent years. In this work, it was studied the use of natural clays of the state of Sergipe, with high levels of kaolinite and montmorillonite as adsorbent materials to remove Pb (II), Cd (II) and Cu (II) in aqueous solution. It was investigated the adsorption conditions including contact time, pH and adsorption isotherms. Using kaolinite equilibrium of adsorption for the three metals was reached at about 30 min, and a contact time of 60 min was chosen. In the beginning of study was conducted at pH of metal nitrate solutions (pH 5.2 ± 0.2) resulting in a maximum removal of 86.0 %, 43.2 % and 34.3 % for Pb (II), Cd (II) and Cu (II) respectively. The pH 7.0 was determined to be the most efficient for the removal of Pb (II) ( 99.9 %), Cd (II) (82.9 %) and Cu (II) (97.9 %). The Langmuir isotherm was the model with the best fit to the adsorption data obtained for the three metals, with Qo of 1.511 mg g-1 for Pb (II); 0.853 mg g-1 for Cd (II) and 0.417 mg g-1 for Cu (II). In the application of natural clay containing montmorillonite, it was obtained; high removal percentages for Pb (II), Cd (II) and Cu (II). The adsorption equilibrium was reached in the first minutes and the contact time of 30 min was selected, with maximum adsorption of 99.54 %; 93.37 %; 99.48 % for Pb(II), Cd (II) and Cu (II) in natural pH of metal in the pH (pH 5.2 ± 2). In pH study, it was observed that the pH variations did not alter significantly the adsorption of metals. Among the models applied, Langmuir was the best fitted one for the three adsorbents applied in this work with Qo of 6.98 mg g-1 1.48 mg g-1 and 2.07 mg g-1 for Pb (II), Cd (II) and Cu (II) respectively. The results show clays that have high levels either kaolinite or montmorillonite show appropriate features for application in the process of adsorption of Pb (II), Cd (II) and Cu (II).
A contaminação por metais tóxicos representa um sério problema ambiental. Inúmeras pesquisas têm sido desenvolvidas tendo como objetivo a remediação ambiental. A adsorção tem sido um dos processos mais utilizados por pesquisadores nos últimos anos para remover metais. No presente trabalho, foi estudada a utilização das argilas naturais do estado de Sergipe, contendo alto teor de caulinita e montmorilonita como materiais adsorventes para remoção do Pb (II), Cd (II) e Cu (II) em solução aquosa. Foram investigadas as condições de adsorção incluindo tempo de contato, pH e isotermas de adsorção. Na utilização da argila caulinita natural, o equilíbrio de adsorção para os três metais foi alcançado em torno de 30 min, sendo utilizado nos experimentos o tempo de contato de 60 min. Inicialmente, o estudo foi desenvolvido no pH das soluções dos nitratos dos metais (pH 5,2 ± 0,2), obtendo-se uma remoção máxima de 86,0 % para o Pb (II), 43,2 % para Cd (II) e 34,3 % para Cu (II). A avaliação do efeito do pH sobre a adsorção mostrou que o aumento do pH favorece a remoção até certo valor, acima do qual os íons metálicos são precipitados como hidróxidos insolúveis. O pH 7,0 foi determinado como sendo o mais adequado para a remoção do Pb (II) ( 99,9 %), Cd (II) (82,9 %) e Cu (II) (97,9 %). A isoterma de Langmuir foi a que melhor se ajustou aos dados de adsorção obtidos para os três metais, com Qo de 1,51 mg g-1 para o Pb (II); 0,85 mg g-1 para o Cd (II) e 0,42 mg g-1 para o Cu (II). Na aplicação da argila natural contendo montmorilonita, obtiveram-se altas percentagens de remoção para o Pb (II), Cd (II) e Cu (II). O equilíbrio de adsorção foi alcançado nos primeiros minutos, sendo otimizado o tempo de contato de 30 min, com máxima adsorção de 99,54 %, 93,37 %, 99,48 % para o Pb (II), Cd (II) e Cu (II) em pH natural das soluções dos respectivos metais (pH 5,2 ± 0,2). No estudo de pH observou-se que a variação deste mesmo não alterou significativamente a adsorção dos metais. Entre os modelos aplicados, o de Langmuir mostrou-se mais adequado para os três adsorvatos estudados neste trabalho, com Qo de 6,98 mg g-1 para o Pb (II); 1,48 mg g-1 para o Cd (II) e 2,07 mg g-1 para o Cu (II). Os resultados apresentados mostram que as argilas contendo alto teor de caulinita ou montmorilonita apresentam características apropriadas para sua aplicação no processo de adsorção do Pb (II), Cd (II) e Cu (II).
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Li, Shanghao. "Theoretical Insight into Mechanisms of Natural and Artificial Metalloproteases". Scholarly Repository, 2011. http://scholarlyrepository.miami.edu/oa_theses/265.
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In this study, theoretical and computational approaches have been utilized to investigate the mechanisms of natural and artificial metalloproteases. The active sites of most natural metalloproteases contain a tetrahedral zinc center, coordinated by three amino acid residues combinated from His(N), Cys(S), Glu(O), and Asp(O) with a water molecule as the fourth ligand. However, the roles played by the ligands environment in the catalytic functions of enzyme are not clear. In this study, the effects of different ligand combinations (NS2, N2S, N2O, N3, S3, NO2 and NSO) in the mechanism were investigated energy barriers were compared. The machanism and energetics of the substrate bound artificial metalloproteases Ni(II)cyclen (cyclen: 1,4,7,10-tetraazacyclododecane) and Cd(II)cyclen have been investigated. In addition, the mechanism of hydrolysis of Phe-Phe peptide bond catalyzed by another artificial metalloprotease [Pd(H2O)4]2+ has also been studied.
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Arican, Zafer. "Vision-based Robot Localization Using Artificial And Natural Landmarks". Master's thesis, METU, 2004. http://etd.lib.metu.edu.tr/upload/12605333/index.pdf.
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In mobile robot applications, it is an important issue for a robot to know where it is. Accurate localization becomes crucial for navigation and map building applications because both route to follow and positions of the objects to be inserted into the map highly depend on the position of the robot in the environment.
For localization, the robot uses the measurements that it takes by various devices such as laser rangefinders, sonars, odometry devices and vision. Generally these devices give the distances of the objects in the environment to the robot and proceesing these distance information, the robot finds its location in the environment.
In this thesis, two vision-based robot localization algorithms are implemented. The first algorithm uses artificial landmarks as the objects around the robot and by measuring the positions of these landmarks with respect to the camera system, the robot locates itself in the environment. Locations of these landmarks are known. The second algorithm instead of using artificial landmarks, estimates its location by measuring the positions of the objects that naturally exist in the environment. These objects are treated as natural landmarks and locations of these landmarks are not
known initially.
A three-wheeled robot base on which a stereo camera system is mounted is used as the mobile robot unit. Processing and control tasks of the system is performed by a stationary PC. Experiments are performed on this robot system. The stereo camera system is the measurement device for this robot.
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Cameron, Craig G. "Natural and artificial fluorescence on 3-dimensional bioorganic nanostructures". Diss., Georgia Institute of Technology, 2014. http://hdl.handle.net/1853/53451.
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A challenge exists for understanding the origin of color for structurally colored, 3-dimensional bioorganic nanostructures, such as the scales of butterflies, beetles, and moths. Complex, hierarchical structures found within such scales create the overall scale appearance. The controlled alteration of color through material deposition and the addition of new optical functionalities to such structures are other areas of scientific interest. This dissertation addresses these challenges with a first-of-its-kind, systematic isolation (deconstruction) of scale component nanostructures, followed by evaluation of optical property/structure correlations. The additive deposition (constructive alteration) of emissive materials to structurally-colored templates complements this deconstructive approach towards understanding the origin of color in butterfly scales. Discoveries made through this work may help advance the bioinspired design of synthetic optical structures and subsequent color control through the addition of multilayered, emissive optical components.
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Ramey, Holly Rene. "Mapping natural and artificial selection events in animal genomes". Thesis, University of Missouri - Columbia, 2016. http://pqdtopen.proquest.com/#viewpdf?dispub=10182613.
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Oliveira, Inês Mouco de. "Entre o natural e o artificial, uma topografia urbana". Master's thesis, Universidade de Lisboa. Faculdade de Arquitetura, 2016. http://hdl.handle.net/10400.5/13556.
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Sichula, Vincent A. "Flavins and Their Analogues as Natural and Artificial Catalysts". Bowling Green State University / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1294288149.
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Smith, Terrance J. "Foot and Ankle Injuries: Artificial Turf vs. Natural grass". Wittenberg University Honors Theses / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=wuhonors1470240556.
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Rosolem, Rafael. "Land Surface Processes In Natural and Artificial Tropical Ecosystems". Diss., The University of Arizona, 2010. http://hdl.handle.net/10150/194510.
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Land Surface Parameterization (LSP) schemes have evolved from simple tipping-bucket models to fully interactive models, including parameterizations which account for exchanges of momentum, energy, mass, and biogeochemistry. As the demand for greater realism has increased, so has the complexity of LSPs which now includes some parameters that may not be universally relevant to all regions of the globe. The performance of LSP schemes depends on the magnitude of structural, data-related (input and output), and parameter uncertainties in the model. Parameter estimation uncertainty can be reduced by calibrating LSPs against measurements available at field sites. Given the multiple outputs of the models, multi-objective optimization approaches are performed. Some of the parameter values used in LSPs have originally obtained from laboratory studies which analyzed plant behavior under a range of conditions in enclosed chambers. The research described in this dissertation takes advantage of currently available data from several eddy covariance flux towers located mainly in the Brazilian Amazon basin to estimate parameter values of a widely-used LSP scheme, version 3 of the Simple Biosphere model (SiB3). Background climatological data was used to assess the representativeness of the data collection period that might have affected model calibration. Variance-based sensitivity analysis was then used to investigate potential structural deficiencies in SiB3 and to reduce the dimensionality of the subsequent optimization by identifying those model parameters that merit calibration. Finally, some structural and conceptual aspects of SiB3 were tested inside Biosphere 2 Tropical Rain Forest biome (B2-TRF) under meteorological conditions that resemble those predicted in future climate scenarios for the Amazon basin.
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Säberg, Mikael. "Sustainability of Artificial Turf Fields : Comparative life cycle assessment of artificial and natural turf fields". Thesis, Linköpings universitet, Industriell miljöteknik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-177901.
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Soccer accounts for a third of the Swedish sports movement with 3 503 fields of both natural and artificial turf. The European Union will make a decision in 2021 on how to handle the issue of rubber performance infill. This infill can be found in artificial turf fields and are used for performance properties. The problem with this infill is the microplastics that spreads into the nature which is considered as toxic. Because of this the EU have decided to either ban or provide mandatory rules to reduce the spread of rubber performance infill. The north and the majority of Sweden’s climate is not adapted for play of soccer on natural turf according to FIFA, and EU want to ban or provide mandatory rules for artificial turfs. This action from the EU can perturb the entire Swedish sports movement since soccer accounts for a third of that movement. This study was therefore created to show if artificial turf fields are as bad for the environment as rumours has said compared with the natural turfs. To investigate this, a life cycle assessment (LCA) was performed regarding the global warming potential (GWP) and embodied water consumption for three different field types: an artificial turf field with recycled SBR, an artificial turf field with cork and a natural turf field. The result visualised that a natural turf field had the highest embodied water consumption and the highest impact on the GWP of a ten-year life cycle while the artificial turf field with recycled SBR had the least embodied water consumption and the least impact on the GWP. The findings of this LCA were that Sweden for the moment is dependent on artificial turf and the rubber performance infill, since the material properties are the best adapted to their climate. Therefore, a ban would be a risk for the Swedish sports movement. It was also revealed that natural turf fields in Sweden consumes at least 50 % municipal drinking water when irrigate. The high GWP impact came from the production of fertilisers (NPK). This report has shown how artificial turf and natural turf can work together in an industrial symbiosis by making the artificial turf field constructed to collect rainwater and use that water to irrigate the natural turf with.
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Dastjerdi, Roya y Fatemeh Avareh Sadrabadi. "Engineering of Wool Nano-clay Functionalization for Different Approaches". Thesis, Sumy State University, 2013. http://essuir.sumdu.edu.ua/handle/123456789/35315.
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The research has conducted finishing of wool fabrics by clay nano-layers and its effect on the felting properties of treated wool fabrics. Natural and modified montmorillonite used to modify the fabrics. To this end, the knitted wool fabrics have been treated under ultrasound. Then, the samples have been subjected to felting operation with two acidic and alkaline conditions. Felting properties of samples were investigat-ed and compared with control samples. According to the results, felting properties were affected by nano-clay types and pH. Therefore, nano-clay finishing can increase felting potential, or conversely, increase re-sistance to shrinkage according to pH of felting solution and nano-clay surface characteristics. Thus, in ba-sis of ultimate goal the required condition can be controlled to boost felting properties or prevent fabric shrinkage.
When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/35315
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Samineni, Keerthi. "Adsorption of Bisphenol S from Water Using Natural Sorbents". University of Dayton / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=dayton151256696989552.
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MacDonald, Elaine. "Lead and copper retention by a shale derived artificial illite clay soil : a multicomponent study". Thesis, McGill University, 2001. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=38078.
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A multicomponent study of Pb and Cu retention was performed using a selective contamination technique. Soil components were selectively extracted from a multicomponent illite clay artificial soil using extractants commonly utilized in sequential extraction studies. Pb and Cu retention by the soil components: carbonates, amorphous oxides, natural organic matter and the clay minerals, were examined. It was found that the clay minerals are the most important contributor to the retention of Pb and Cu, which in this case is predominantly illite. Adsorption and not precipitation is believed to be the controlling mechanism of retention although retention by precipitation increased with increasing pH.Pb and Cu retention from a single metal solution as well as competitive retention of Pb and Cu from a mixed metal solution on each of the untreated and treated artificial soils were examined. Competitive adsorption experiments found that Pb was preferred over Cu for adsorption by the untreated and treated artificial soils and greater quantities of Pb were retained than Pb applied in composite with Cu or Cu applied as a single metal. Pb removed from the artificial soil, using sequential extraction analysis, was compared to Pb retained and mass balance was observed.
The artificial soil was found to contain both variable and constant charge surfaces but the artificial soil contaminant interaction was modelled best using only the variable charge surface. The presence of ion exchange adsorption and Ca competition are examined.
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Ealey, Douglas. "Natural language acquisition in large scale neural semantic networks". Thesis, University of Southampton, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.310843.
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Zhu, Shuxiang. "Big Data System to Support Natural Disaster Analysis". Case Western Reserve University School of Graduate Studies / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=case1592404690195316.
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Whalen, Joann. "Evaluation of soil Arylsulfatase enzymes using natural and artificial substrates". Thesis, McGill University, 1995. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=22826.
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The response of soil arylsulfatase enzymes to natural and artificial substrates was evaluated. An immobilized arylsulfatase reactor was used to hydrolyse ester sulfate compounds in two soils with different morphological properties and management schemes. Hydrolysable ester sulfates cleaved by the immobilized arylsulfatase reactor constituted 35 to 55% of the HI-reducible S in these soils. Naturally occurring low molecular weight (LMW) ester sulfate compounds were found to accumulate in soil and persist during storage. These compounds were examined as the naturally occurring substrate for soil arylsulfatase enzymes.Arylsulfatase activity was evaluated using artificial (p-nitrophenol sulfate) and natural (LMW ester sulfates) substrates. The response of arylsulfatase activity in soil and humic-arylsulfatase complexes to p-nitrophenol sulfate did not reflect the ability of these complexes to hydrolyse natural soil substrates.
A preliminary experiment was conducted to examine arylsulfatase activity and soil sulfur in relation to sulfur in plant tissue and grain from wheat. Tissue sulfur was more strongly associated with soil sulfur than wheat grain.
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Bentley, Katie Anne. "Adaptive behaviour through morphological plasticity in natural and artificial systems". Thesis, University College London (University of London), 2006. http://discovery.ucl.ac.uk/1444539/.
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Our concept of intelligence is changing. Embodiment has led to the rise of morphologies in Artificial Intelligence (AI) research. This thesis focuses on two research questions: 1) How can system morphologies, well-adapted to changing environments, be designed? 2) How can adaptive behaviour be generated through morphology? It is the fundamental argument of this thesis that morphological plasticity (MP), the environmentally induced variation in growth or development, can provide a solution to both questions. Specifically, this thesis is based around a detailed study of diatom valve morphogenesis. Diatoms, a unicellular organism, construct intricate siliceous structures (valves) around themselves which exhibit high plasticity to the environment. Diatom valve morphogenesis is a good example of how morphologies can be well-adapted to changing environments, an open problem in AI, and how adaptive behaviour can be generated through morphological processes alone. Through a constructivist approach this thesis contributes to both understanding of MP in natural systems and the design of MP algorithms for artificial adaptive systems. Several original models and frameworks are defined within this thesis: the Nature's Batik Model of basic diatom valve morphogenesis the Cellanimat, a 'Dynamic Morphology' based on the unicell, capable of MP driven adaptive behaviour through its unique 'Artificial Cytoskeleton' model of cytoskeletal dynamics the Environment-Phenotype Map framework and the Cellanimat Colony Model, which combines all previous models for the investigation of MP mechanisms during diatom colony formation. Cellanimat dynamics and optimization are thoroughly investigated and the model is shown to be multi functional, evolvable, scalable and reasonably robust.
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Wulff, Brande Bruce Hertel. "Natural and artificial evolution of tomato Cf-9 resistance homologues". Thesis, University of East Anglia, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.249755.
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Demirtaş, Fatma Aslıhan 1970. "Artificial nature : water infrastructure and its experience as natural space". Thesis, Massachusetts Institute of Technology, 2000. http://hdl.handle.net/1721.1/65716.
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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Architecture, 2000.Includes bibliographical references (p. 159-163).
This work is about water infrastructure and its experience as urban and natural space. It deals with the concepts of nature/geography, technology, and the integral experiential space by analyzing water dams and reservoirs that are more than utilitarian structures. In the process of formulating the concept of ARTIFICIAL NATURE, an expanded definition of 'built activity' to embrace landscape/nature, infrastructure, and technology as well as imaginative and mental space is pursued. The specific sites of investigation range from Thrace to Central and Southeastern Anatolia in Turkey from 1920-2000.
by Fatma Aslıhan Demirtaş.
S.M.
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Li, Dan M. Arch Massachusetts Institute of Technology. "Fluid atmospheres : adaptive interplay between natural and artificial light projection". Thesis, Massachusetts Institute of Technology, 2016. http://hdl.handle.net/1721.1/103472.
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Thesis: M. Arch., Massachusetts Institute of Technology, Department of Architecture, 2016.Cataloged from PDF version of thesis.
Includes bibliographical references (pages 94-95).
Imagine. This is the same daily route you travel and the same space you pass through. And it is not. How do we create an adaptive and customized space with no materials at all? Can the generic be customized and specific at the same time? Given extra layers of "light" a compose-able architecture is yet to come. A building is a living, breathing space that is ever moving and rapidly morphing - its animus is time. Take a closer look at the surfaces that enclose our space: there are screens with news, lectures, movie clips; there are windows, shadows and shade created by lights of all different kinds; there are colors and ornamentations that inform us of the history of our architectural lineage. Sunlight naturally creates an evolving atmosphere with the change in time and the seasons; now, with new technologies, we can create even more dynamic atmospheres with light that engage and collaborate with the sun. Light exists in two forms: natural light and artificial light created from technology. Sunlight creates our everyday perception of the physical world, and thus, our ability to understand and live in the space around us. Nevertheless, "digital light" is becoming a larger and larger part of our lives, as we perceive and create information through the medium of a screen. However, "digital light" does not always need to be flat -- through projection mapping, we can create a three-dimensional light that leaves the 2D surface of the screen and is responsive to the environment of the physical world. Using this method, our perception of the physical space will not only change due to the passing of the sun, but also from our own agency in creating altered environments through designed projection systems. This project creates a methodology and a toolkit to design dynamic spaces with natural and projection lighting that allows for customization and alterations of space. Through this system, the static building itself becomes the instrument that is played. This project also demonstrates these tools through investigating projections with light in the atrium of MIT Brain and Cognitive Sciences Complex building.
by Dan Li.
M. Arch.
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Raj, Towfique. "Molecular signatures of natural and artificial selection in mammalian genomes". Thesis, University of Cambridge, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.609021.
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Faísca, Pedro Miguel Portela. "Comparison of organic matter decomposition between natural and artificial ponds". Master's thesis, Universidade de Évora, 2019. http://hdl.handle.net/10174/24405.
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Litter decomposition is a key ecosystem service within aquatic ecosystems and is a complex process that is sensitive to environmental factors. The role of microbial and macrofaunal decomposers, and how it changes across environmental gradients is not yet fully understood. Decomposition was assessed across 6 biogeographical regions to determine the role of macroinvertebrates in this ecosystem service. Decomposition was estimated using standardized cotton strips, which were deployed in the mesocosms of each region. The role of macroinvertebrates was tested with an exclusion experiment which allowed or prevented the access of macroinvertebrates to cotton strips, a similar experiment was also conducted in natural ponds. After 64 days the cotton strips were collected, and mass loss and tensile strength were measured. There were significant differences in the rate of decomposition across different regions and no differences were found between systems. Macroinvertebrates played an important role, with gatherers being major players; Resumo:
A decomposição é um serviço de ecossistema chave e um processo complexo sensível a factores ambientais. O papel de decompositores microbianos e da macrofauna, e como este papel muda num gradiente ambiental não é completamente entendido. A decomposição foi avaliada em 6 zonas biogeográficas para determinar o papel de macroinvertebrados neste serviço de ecossistema. A decomposição foi estimada utilizando tiras de algodão, colocadas em mesocosmos nas diferentes regiões. O papel dos macroinvertebrados foi testado através de uma experiência de exclusão que permitia ou impedia o acesso de macroinvertebrados às tiras, uma experiência semelhante foi realizada em charcos naturais. Ao fim de 64 dias, as tiras de algodão foram recolhidas e a perda de massa e tensão foram quantificadas. Encontraram-se diferenças significativas na decomposição entre as diferentes regiões, mas não se observaram diferenças entre sistemas. Os macroinvertebrados têm um papel importante neste serviço de ecossistema, sendo as espécies colectoras as mais importantes
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Li, Junyan. "Computational biomechanics/biotribological modelling of natural and artificial hip joints". Thesis, University of Leeds, 2013. http://etheses.whiterose.ac.uk/5500/.
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The excellent hip function and potential degeneration are closely linked with the unique structure of the joint cartilage that is principally composed of a solid phase and a fluid phase. Once damaged, the joint may need to be replaced by prosthesis in order to restore function in hip kinematics and kinetics. However, to what extent this can be achieved has yet to be quantified. On the other hand, the role of fluid pressurisation which plays in hip function has been poorly understood. The aim of this thesis was to address these issues. To evaluate the gait abnormality, particularly in terms of hip contact forces, a musculoskeletal model of lower extremity was constructed in a rigid-body dynamics frame, and the hip kinematics and kinetics were determined and cross-compared for a group of asymptomatic total hip replacement (THR) patients, THR patients with symptoms of symptomatic leg length inequality (LLI) and normal healthy people. Significant abnormal patterns in gait kinetics were observed for the asymptomatic THR patients, and this abnormality was greater for the LLI patients. To understand contact mechanics and the associated fluid pressurisation within the hip cartilage, a three dimensional finite element (FE) hip model with biphasic cartilage layers were developed. The protocol was compared to other solvers. A set of sensitivity studies were undertaken to evaluate the influence of model parameters, and then the model was evaluated under a range of loads with different activities. In all the cases, the fluid supported over 90% of the load for a prolonged period, potentially providing excellent hip function and lubrication. The musculoskeletal model and FE joint were combined to investigate the performance of the non-operated joint of the THR / LLI patients during gait which was found to function in a mechanically abnormal but not adverse environment. Lastly, the methodology of the biphasic hip modelling was validated using an experimental porcine hip of hemiarthroplasty. Good agreement was achieved between the FE predictions and the experimental measurement of the contact area.
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Pilavtepe, Müge [Verfasser] y N. [Akademischer Betreuer] Willenbacher. "Microstructure and Rheology of Colloidal Natural Clay Mineral Dispersions / Müge Pilavtepe ; Betreuer: N. Willenbacher". Karlsruhe : KIT-Bibliothek, 2018. http://d-nb.info/1154856674/34.
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Dittmar, George William. "Object Detection and Recognition in Natural Settings". PDXScholar, 2013. https://pdxscholar.library.pdx.edu/open_access_etds/926.
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Much research as of late has focused on biologically inspired vision models that are based on our understanding of how the visual cortex processes information. One prominent example of such a system is HMAX [17]. HMAX attempts to simulate the biological process for object recognition in cortex based on the model proposed by Hubel & Wiesel [10]. This thesis investigates the ability of an HMAX-like system (GLIMPSE [20]) to perform object-detection in cluttered natural scenes. I evaluate these results using the StreetScenes database from MIT [1, 8]. This thesis addresses three questions: (1) Can the GLIMPSE-based object detection system replicate the results on object-detection reported by Bileschi using HMAX? (2) Which features computed by GLIMPSE lead to the best object-detection performance? (3) What effect does elimination of clutter in the training sets have on the performance of our system? As part of this thesis, I built an object detection and recognition system using GLIMPSE [20] and demonstrate that it approximately replicates the results reported in Bileschi's thesis. In addition, I found that extracting and combining features from GLIMPSE using different layers of the HMAX model gives the best overall invariance to position, scale and translation for recognition tasks, but comes with a much higher computational overhead. Further contributions include the creation of modified training and test sets based on the StreetScenes database, with removed clutter in the training data and extending the annotations for the detection task to cover more objects of interest that were not in the original annotations of the database.
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Lacerda, Jose Neves de. "Generalização de fatos na compreensão de textos em linguagem natural". reponame:Repositório Institucional da UFSC, 1996. https://repositorio.ufsc.br/xmlui/handle/123456789/158062.
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Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro TecnologicoMade available in DSpace on 2016-01-08T21:01:46Z (GMT). No. of bitstreams: 1 104809.pdf: 2836599 bytes, checksum: 361e8157da674b3f2eeef6595b3db383 (MD5) Previous issue date: 1996
As comunicações humanas são, de forma geral, incompletas em relação ao seu conteúdo. Muito conhecimento é transmitido em poucas palavras. Isso é possível porque existe, em nossa memória, um conhecimento pré-existente sobre o mundo, suas coisas, e interrelações existentes entre estas coisas, que nós utilizamos para complementar as lacunas existentes nas comunicações recebidas. Sistemas quc compreendam a linguagem humana, estudados em Inteligência Artificial, precisam ser capazes de fazer esse tipo de atividade, para nós tão natural. O uso adequado desse recurso dá ao sistema uma capacidade de interpretação maior do que a oferecida pela pura análise sintático-semântica das sentenças. O objetivo dessa dissertação é descrever um processo automático de criação dessas estruturas de dados, de forma a poderem, posteriormente, ser utilizadas na interpretação de textos em linguagem natural. Tratadas aqui como ?fatos genéricos?, seu papel é o de representar aquilo que conhecemos como senso comum. Essa dissertação descreve um sistema que ?compreende? textos escritos em linguagem natural e, a partir dos fatos identificados nessa compreensão, constrói estruturas semânticas, manipuláveis, que representam genericamente estes fatos. Apresentamos a base teórica, as definições das estruturas semânticas e das bases de dados utilizadas, os algoritmos de análise, interpretação e generalização de fatos, e demonstramos o funcionameato do sistema implementado. Problemas relacionados às alternativas adotadas são discutidos.