Дисертації з теми "Fluid Art"
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1
Thompson, Seth Aaron. "Art Unfettered: Bergson and a Fluid Conception of Art." Thesis, University of North Texas, 2018. https://digital.library.unt.edu/ark:/67531/metadc1248388/.
Повний текст джерелаАнотація:
This dissertation applies philosopher Henri Bergson's methodology and his ideas of duration and creativity to the definitional problem of art, particularly as formulated within analytic aesthetics. In mid-20th century, analytic aesthetics rejected essentialist definitions of art, but within a decade, two predominant definitions of art emerged as answers to the anti-essentialism of the decade prior: functionalism and proceduralism. These two definitions define art, respectively, in terms of the purpose that art serves and in terms of the conventions in place that confer the status of art onto artifacts. Despite other important definitions (including historical and intentionalist definitions), much of the literature in the analytic field of aesthetics center on the functional/procedural dichotomy, and this dichotomy is an exclusive one insofar as the two definitions appear incompatible with each other when it comes to art. I use Bergson's methodology to demonstrate that the tension between functionalism and proceduralism is an artificial one. In turn, abandoning the strict dichotomy between these two definitions of art opens the way for a more fluid conception of art. Using Bergson's application of duration and creativity to problems of laughter and morality, I draw parallels to what a Bergsonian characterization would entail.
2
Lundberg, Lukas. "Art Directed Fluid Flow With Secondary Water Effects." Thesis, Linköpings universitet, Medie- och Informationsteknik, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-81808.
Повний текст джерелаАнотація:
This thesis describes methods for applying secondary water effects as spray, foam, splashes and mist to a fluid simulation system. For an art direction control over the base fluid flow a Fluid Implicit Particle solver with custom fields is also presented. The methods build upon production techniques within the visual effects industry, fluid dynamics and relevant computer graphics research. The implementation of the methods is created within Side Effects Software Houdini.
3
Jackson, Matthew. "Re-presenting gender fluid identity in a contemporary arts practice." Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 2011. https://ro.ecu.edu.au/theses/430.
Повний текст джерелаАнотація:
This dissertation addresses the paucity of representation of gender fluid identity within contemporary imagery. An examination of historical and socio-political structures inherent in modern Western society serves as a foundational position for a broader exploration of differently gendered communities globally. The case is made for contemporary art to be encouraged as a tool for the emancipation of subjugated gender fluid identities. Examples of contemporary gender fluid visual art and artists are presented to illustrate the ability of art to enable agency within the broader gender fluid community. Finally, a commentary on my own artwork is presented and discussed in relation to the research and conclusions advanced within this dissertation.
4
Nakamura-Mather, Mika. "Notions of Home: Constant, Fluid, and Mobile." Thesis, Griffith University, 2017. http://hdl.handle.net/10072/370354.
Повний текст джерелаАнотація:
I have spent more than a quarter of a century living outside my homeland of Japan. In recent visits to Japan, I have noticed that my sense of belonging is growing stronger. This has caused me to question whether this is simply nostalgia or something deeper. I wonder whether my prolonged exposure to other cultures has enhanced my appreciation of my own, or whether I am losing my cultural identity and the idea of home is becoming more attractive because it feels familiar and safe.
Through my studio work, I seek to juxtapose the present with the past, to examine the role that memory plays in our notions of home, and particularly to discover how my memories influence my emotional response to geographical and cultural dislocation.
In this exegesis, I examine the nature of memory and the idea that home is not merely a place on a map. My research investigates whether a particular material associated with a specific place—in my case, wood—can be fundamental to developing a better understanding of who we are, where we come from, and why we call one place home over another.Thesis (PhD Doctorate)
Doctor of Visual Arts (DVA)
Queensland College of Art
Arts, Education and Law
Full Text
5
Jane, Sarah. "Fluid Experience." Kent State University / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=kent1353468701.
Повний текст джерела
6
Shepherd, Neta-Grace Coleen. "Fluid Realities: A Light on Life's Journey." VCU Scholars Compass, 2014. http://scholarscompass.vcu.edu/etd/3588.
Повний текст джерелаАнотація:
Images of nature and family comprise the gestural and abstracted interpretations of my life events. I use my photographs as inspiration for my work. I fuse layers of color, light, and line into glass and onto wood to suspend a personal memory. I want to capture those moments that flit by in life and envelop them in the media.
In my fused glass work, I manipulate color, light, and line. In these pieces, I layer frits and sheets of glass onto an abstract sculpted relief of fiberglass and fuse them into one thick slab. The sculpted relief creates a textured deflection of light. In each layer of glass, I encapsulate simple line drawings of my family, elements of the landscape, and organic shapes.
In my works on wood, I pour and layer transparent color using acrylic and a water-based polyurethane mixture. I do not fully cover the natural grain of the wood but allow it to contribute to the imagery. I repeat linear marks and create layers of texture using a palette knife, and attach mud and caulk to the natural surface. I further manipulate the surfaces by sanding and carving to express my emotions and memories. The layered media symbolically references layers of time in my personal journey.
7
Webster, Andy. "Finding fluid form : a process aesthetic as a means to engage with the prevailing entitative model of thinking in ecological art." Thesis, University of the Arts London, 2011. http://ualresearchonline.arts.ac.uk/5453/.
Повний текст джерелаАнотація:
This thesis considers common approaches to eco-art practice and its established discourses. Through a critical review of the field it identifies problems in practice and theory that are potentially counterproductive. It outlines methods used in eco-art that, whilst seeking to address environmental concerns, may unintentionally perpetuate the approaches and attitudes of the prevailing view. The thesis argues that as these approaches and attitudes are widely understood to lie at the cause of current problems its continued use is inappropriate for engaging with ecological issues. In response to this problem the thesis draws together insights from arts practice and theory, Systems Thinking, Cybernetics, Artificial Life research, Deep Ecology and Process Thinking. It develops an experimental framework to guide the initiation, production, dissemination and evaluation of arts practice, which can critically engage with the approaches and attitudes of the prevailing view, but do so without perpetuating these. For the purposes of this thesis the framework is called a process aesthetic. The thesis describes how the process aesthetic is developed and tested through the undertaking of new creative practice, and the critical reflection upon this. The written component of the thesis concludes with an evaluation of the relevance and potential of a process aesthetic, and a consideration of what it might offer to our understanding of ecological art. The thesis contributes to the field of eco-art by drawing upon thinking and practices normally considered peripheral to its discourses. This identifies problems, which contradict its aim of challenging the approaches and attitudes of the prevailing view - problems which to date have been under-acknowledged and not adequately theorised. It establishes that arts practice guided by the process aesthetic demonstrates an approach that can overcome problems recognised within existing eco-art and can act as a critical tool for disturbing the approaches and attitudes of the prevailing view. The thesis establishes that the process aesthetic can be used as a guide for future eco-arts practice and can be a means of regrouping existing artworks, which would normally be overlooked by eco-art discussions. This extends the diversity of eco-art discussions to positively broaden its critical discourses. It thus offers a new and appropriate methodology for arts practice that seeks to engage with environmental issues and ecological thinking.
8
Giraud, Carrier Samuel Charles Gérard. "Retiming Smoke Simulation Using Machine Learning." BYU ScholarsArchive, 2020. https://scholarsarchive.byu.edu/etd/8106.
Повний текст джерелаАнотація:
Art-directability is a crucial aspect of creating aesthetically pleasing visual effects that help tell stories. A particularly common method of art direction is the retiming of a simulation. Unfortunately, the means of retiming an existing simulation sequence which preserves the desired shapes is an ill-defined problem. Naively interpolating values between frames leads to visual artifacts such as choppy frames or jittering intensities. Due to the difficulty in formulating a proper interpolation method we elect to use a machine learning approach to approximate this function. Our model is based on the ODE-net structure and reproduces a set of desired time samples (in our case equivalent to time steps) that achieves the desired new sequence speed, based on training from frames in the original sequence. The flexibility of the updated sequences' duration provided by the time samples input makes this a visually effective and intuitively directable way to retime a simulation.
9
Tavano, Matteo. "Seismic response of tank-fluid systems: state of the art review and dynamic buckling analysis of a steel tank with the added mass method." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2012. http://amslaurea.unibo.it/3006/.
Повний текст джерела
10
Pelzer, Elise Sarah. "Microbial colonisation of human follicular fluid and adverse in vitro fertilisation outcomes." Thesis, Queensland University of Technology, 2011. https://eprints.qut.edu.au/49122/1/Elise_Pelzer_Thesis.pdf.
Повний текст джерелаАнотація:
This study, investigating 263 women undergoing trans-vaginal oocyte retrieval for in vitro fertilisation (IVF) found that microorganisms colonising follicular fluid contributed to adverse IVF (pre-implantation) and pregnancy (post-implantation) outcomes including poor quality embryos, failed pregnancy and early pregnancy loss (< 37 weeks gestation). Some microorganisms also showed in vitro growth patterns in liquid media that appeared to be enhanced by the hormonal stimulation protocol used for oocyte retrieval. Elaborated cytokines within follicular fluid were also associated with adverse IVF outcomes.
This study is imperative because infertility affects 16% of the human population and the numbers of couples needing assistance continues to increase. Despite significant improvements in the technical aspects of assisted reproductive technologies (ART), the live birth rate has not increased proportionally. Overt genital tract infection has been associated with both infertility and adverse pregnancy outcomes (including miscarriage and preterm birth) as a direct result of the infection or the host response to it. Importantly, once inflammation had become established, medical treatment often failed to prevent these significant adverse outcomes. Current evaluations of fertility focus on the ovary as a site of steroid hormone production and ovulation. However, infertility as a result of subclinical colonisation of the ovary has not been reported. Furthermore, identification of the microorganisms present in follicular fluid and the local cytokine profile may provide clinicians with an early indication of the prognosis for IVF treatment in infertile couples, thus allowing antimicrobial treatment and/or counselling about possible IVF failure. During an IVF cycle, multiple oocytes undergo maturation in vivo in response to hormonal hyperstimulation. Oocytes for in vitro insemination are collected trans-vaginally. The follicular fluid that bathes the maturing oocyte in vivo, usually is discarded as part of the IVF procedure, but provides a unique opportunity to investigate microbial causes of adverse IVF outcomes. Some previous studies have identified follicular fluid markers that predict IVF pregnancy outcomes. However, there have not been any detailed microbiological studies of follicular fluid.
For this current study, paired follicular fluid and vaginal secretion samples were collected from women undergoing IVF cycles to determine whether microorganisms in follicular fluid were associated with adverse IVF outcomes. Microorganisms in follicular fluid were regarded as either "colonisers" or "contaminants"; colonisers, if they were unique to the follicular fluid sample, and contaminants if the same microorganisms were detected in the vaginal and follicular fluid samples indicating that the follicular fluid was merely contaminated during the oocyte retrieval process. Quite unexpectedly, by these criteria, we found that follicular fluid from approximately 30% of all subjects was colonised with bacteria. Fertile and infertile women with colonised follicular fluid had decreased embryo transfer rates and decreased pregnancy rates compared to women with contaminated follicular fluids. The observation that follicular fluid was not always sterile, but contained a diverse range of microorganisms, is novel. Many of the microorganisms we detected in follicular fluid are known opportunistic pathogens that have been detected in upper genital tract infections and are associated with adverse pregnancy outcomes. Bacteria were able to survive for at least 28 weeks in vitro, in cultures of follicular fluid. Within 10 days of establishing these in vitro cultures, several species (Lactobacillus spp., Bifidobacterium spp., Propionibacterium spp., Streptococcus spp. and Salmonella entericus) had formed biofilms. Biofilms play a major role in microbial pathogenicity and persistence. The propensity of microbial species to form biofilms in follicular fluid suggests that successful treatment of these infections with antimicrobials may be difficult.
Bifidobacterium spp. grew, in liquid media, only if concentrations of oestradiol and progesterone were similar to those achieved in vivo during an IVF cycle. In contrast, the growth of Streptococcus agalactiae and Escherichia coli was inhibited or abolished by the addition of these hormones to culture medium. These data suggest that the likelihood of microorganisms colonising follicular fluid and the species of bacteria involved is influenced by the stage of the menstrual cycle and, in the case of IVF, the nature and dose of steroid hormones administered for the maturation of multiple oocytes in vivo. Our findings indicate that the elevated levels of steroid hormones during an IVF cycle may influence the microbial growth within follicular fluid, suggesting that the treatment itself will impact on the microflora present in the female upper genital tract during pre-conception and early post-conception phases of the cycle.
The effect of the host immune response on colonising bacteria and on the outcomes of IVF also was investigated. White blood cells reportedly compose between 5% and 15% of the cell population in follicular fluid. The follicular membrane is semi-permeable and cells are actively recruited as part of the normal menstrual cycle and in response to microorganisms. A previous study investigated follicular fluid cytokines from infertile women and fertile oocyte donors undergoing IVF, and concluded that there were no significant differences in the cytokine concentrations between the two groups. However, other studies have reported differences in the follicular fluid cytokine levels associated with infertile women with endometriosis or polycystic ovary syndrome. In this study, elevated levels of interleukin (IL)-1 á, IL-1 â and vascular endothelial growth factor (VEGF) in vaginal fluid were associated with successful fertilisation, which may be useful marker for successful fertilisation outcomes for women trying to conceive naturally or prior to oocyte retrieval for IVF. Elevated levels of IL-6, IL-12p40, granulocyte colony stimulating factor (GCSF) and interferon-gamma (IFN ã) in follicular fluid were associated with successful embryo transfer.
Elevated levels of pro-inflammatory IL-18 and decreased levels of anti-inflammatory IL-10 were identified in follicular fluid from women with idiopathic infertility. Successful fertilisation and implantation is dependent on a controlled pro-inflammatory environment, involving active recruitment of pro-inflammatory mediators to the genital tract as part of the menstrual cycle and early pregnancy. However, ongoing pregnancy requires an enhanced anti-inflammatory environment to ensure that the maternal immune system does not reject the semi-allergenic foetus. The pro-inflammatory skew in the follicular fluid of women with idiopathic infertility, correlates with normal rates of fertilisation, embryo discard and embryo transfer, observed for this cohort, which were similar to the outcomes observed for fertile women. However, their pregnancy rate was reduced compared to fertile women. An altered local immune response in follicular fluid may provide a means of explaining infertility in this cohort, previously defined as 'idiopathic'.
This study has found that microorganisms colonising follicular fluid may have contributed to adverse IVF and pregnancy outcomes. Follicular fluid bathes the cumulus oocyte complex during the in vivo maturation process, and microorganisms in the fluid, their metabolic products or the local immune response to these microorganisms may result in damage to the oocytes, degradation of the cumulus or contamination of the IVF culture system. Previous studies that have discounted bacterial contamination of follicular fluid as a cause of adverse IVF outcomes failed to distinguish between bacteria that were introduced into the follicular fluid at the time of trans-vaginal oocyte retrieval and those that colonised the follicular fluid. Those bacteria that had colonised the fluid may have had time to form biofilms and to elicit a local immune response. Failure to draw this distinction has previously prevented consideration of bacterial colonisation of follicular fluid as a cause of adverse IVF outcomes.
Several observations arising from this study are of significance to IVF programs. Follicular fluid is not always sterile and colonisation of follicular fluid is a cause of adverse IVF and pregnancy outcomes. Hormonal stimulation associated with IVF may influence whether follicular fluid is colonised and enhance the growth of specific species of bacteria within follicular fluid. Bacteria in follicular fluid may form biofilms and literature has reported that this may influence their susceptibility to antibiotics. Monitoring the levels of selected cytokines within vaginal secretions may inform fertilisation outcomes. This study has identified novel factors contributing to adverse IVF outcomes and that are most likely to affect also natural conception outcomes. Early intervention, possibly using antimicrobial or immunological therapies may reduce the need for ART and improve reproductive health outcomes for all women.
11
Richartz, Achim. "State of the art digital on-board-electronics vs. potentially disruptive control architectures for hydraulic valves." Technische Universität Dresden, 2020. https://tud.qucosa.de/id/qucosa%3A71191.
Повний текст джерелаАнотація:
Currently discussed trends and new technologies regarding cloud or edge computing imply that even most recent designs and functionalities of digital on-board-control electronics may be outdated and eventually will totally disappear. Additionally, those new technologies attract potential users by promises like new use cases e.g. predictive maintenance or a simplified architecture and reduced installation efforts. On the other hand, automation levels and subsequent requirements are often mixed up or discussed too generally. Nevertheless, what is the rue situation today and in the upcoming years? This paper elaborates the potentials of both approaches – state of the art on-board-control electronics and potentially disruptive control architectures for hydraulic valves in order to take the right decision and reflect the pros and cons for each topology by:
a) Architecture of automation: In Terms of strongly hierarchical or multidimensional connected systems.
b) Requirement of installation: By reflecting the dedicated ecosystems, on levels like plant, machine, subsystems.
c) Maturity of technology: Looking on the user’s perspective.
d) Safety and security: From legal and conformity aspects.
e) Performance needs by specific task: In comparing standard to demanding real life applications.
12
Scalici, Elodie. "Les acides nucléiques circulants : biomarqueurs d'intérêt en Assistance Médicale à la Procréation." Thesis, Montpellier, 2015. http://www.theses.fr/2015MONTT031.
Повний текст джерелаАнотація:
Au cours de ces dernières années, l’utilisation des acides nucléiques circulants comme outils diagnostiques et/ou pronostiques en cancérologie a largement été documentée. Récemment, le développement du diagnostic prénatal non-invasif a également révélé l’intérêt grandissant de ces biomarqueurs en gynécologie-obstétrique. Les acides nucléiques circulants ou extracellulaires ont la particularité d’être facilement détectables dans les fluides biologiques de l’organisme et sont de deux types: (1) l’ADN libre, courts ou longs fragments d’ADN provenant des processus apoptotiques et/ou nécrotiques cellulaires (2) les microARNs, petites séquences d’ARN non codantes, qui régulent l’expression des gènes en interférant avec leurs ARNm cibles. Sachant qu’il a été démontré que le taux d’ADN libre circulant est anormalement élevé dans certaines conditions pathologiques et que les microARNs sont impliqués dans la régulation de nombreux processus biologiques tels que la folliculogénèse et la stéroïdogénèse, ces deux types d’acides nucléiques pourraient alors constituer des biomarqueurs d’intérêt dans le domaine de l’Assistance Médicale à la Procréation. Dans ce travail de thèse, nous avons à la fois mesuré le taux d’ADN libre et analysé les profils d’expression de plusieurs microARNs d’intérêt par PCR quantitative, dans le liquide folliculaire (LF) de patientes prises en charge en fécondation in vitro (FIV). Nous avons observé des taux d’ADN libre significativement élevés ainsi que des profils d’expression de microARNs spécifiques dans le LF de patientes présentant des anomalies de la réserve ovarienne (telles que le syndrome des ovaires micropolykystiques ou une faible réserve ovarienne). Nous avons ensuite évalué le potentiel des acides nucléiques circulants en tant biomarqueurs prédictifs des résultats en FIV. Nous avons démontré que le taux d’ADN libre intra-folliculaire et l’expression de certains microARNs étaient significativement associés à la qualité des embryons obtenus in vitro ainsi qu’à la survenue d’une grossesse clinique. Les acides nucléiques circulants offrent donc de nouvelles perspectives à la fois d’un point de vue diagnostique et pronostique dans la prise en charge de l’infertilité humaineDuring the last years, the use of circulating nucleic acids as diagnostic and/or prognostic tools in cancerology was widely documented. The recent development of non-invasive prenatal testing also reveals the growing interest of these biomarkers in obstetrics and gynecology. The circulating or extracellular nucleic acids have for particularity to be easily detectable in the biological fluids of the body and there are two types: (1) Cell-free DNA (cfDNA), short or long DNA fragments resulting from cellular apoptosis and/or necrosis (2) microRNAs (miRNAs), small non-coding RNA sequences, which regulate gene expression by interfering with their mRNA targets. Since it was demonstrated that cfDNA level is abnormally increased in some pathological conditions and miRNAs are involved in the regulation of several biological processes such as folliculogenesis and steroidogenesis, these two types of nucleic acids could constitute new biomarkers of interest in Assisted Reproductive Technology. In this thesis work, we quantified the cfDNA level and analysed the expression profiles of some miRNAs by quantitative PCR, in follicular fluid (FF) samples from women undergoing in vitro fertilization (IVF) procedure. We observed significant high cfDNA levels as well as specific miRNA expression profiles in FF from women with ovarian disorders (such as polycystic ovary syndrome or low ovarian reserve). Next, we investigated the potential of circulating nucleic acids as predictive biomarkers of IVF outcomes. We demonstrated that the intra-follicular cfDNA level and some miRNA expressions were significantly associated with in vitro embryo quality and the clinical pregnancy outcome. Therefore, the circulating nucleic acids offer new diagnostic and prognostic perspectives in human infertility management
13
Zhang, Junfang. "Computer simulation of nanorheology for inhomogenous fluids." Australasian Digital Thesis Program, 2005. http://adt.lib.swin.edu.au/public/adt-VSWT20050620.095154.
Повний текст джерелаАнотація:
Thesis (PhD) - Swinburne University of Technology, School of Information Technology, Centre for Molecular Simulation - 2005.A thesis submitted in fulfilment of requirements for the degree of Doctor of Philosophy, Centre for Molecular Simulation, School of Information Technology, Swinburne University of Technology - 2005. Typescript. Bibliography: p. 164-170.
14
Tsimpli, Dimitra. "Analysis and challenges in Bubble Curtain Technologies." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2022.
Знайти повний текст джерелаАнотація:
The increasing demand for renewable energy has incited an increase in the evolveing rate of offshore wind energy. To meet the demands, more offshore wind power generators are being installed in the sea, where the air currents are stronger. The majority of the foundation of wind turbines uses mono piles.The installation process of the mono-piles supporting the wind turbines often includes foundation piles,driven into the seabed, using hydraulic impact hammers or vibratory devices. The pile in-
stallation, that is an essential component in the erection of wind farms,has a thwarting by-product : the underwater noise pollution. Continuous high frequency sounds produced by the deformation of the shell of the pipe while it is being hammered to
the sea bottom, can exceed 200 dB re 1μ Pa . Pile driving using impact hammers in open water increases the likelihood that marine mammals suffer disturbance or even instantaneous death, which lead to the implementation of new legislation. The aim of this thesis is to asses: (key points)
1. State of the art in sound attenuation during pile driving operations.
2. Sound characteristics, Attenuation, Soil Models, Response.
3. Perforated Pipe Analysis.
4. Macro, Micro, Nano bubbles.
15
Marcelli, Gianluca, and g. marcelli@imperial ac uk. "The role of three-body interactions on the equilibrium and non-equilibrium properties of fluids from molecular simulation." Swinburne University of Technology. Centre for Molecular Simulation, 2001. http://adt.lib.swin.edu.au./public/adt-VSWT20060112.082425.
Повний текст джерелаАнотація:
The aim of this work is to use molecular simulation to investigate the role of
three-body interatomic potentials in noble gas systems for two distinct
phenomena: phase equilibria and shear flow. In particular we studied the
vapour-liquid coexisting phase for pure systems (argon, krypton and xenon) and
for an argon-krypton mixture, utilizing the technique called Monte Carlo Gibbs
ensemble. We also studied the dependence of the shear viscosity, pressure and
energy with the strain rate in planar Couette flow, using a non-equilibrium
molecular simulation (NEMD) technique.
The results we present in this work demonstrate that three-body interactions
play an important role in the overall interatomic interactions of noble gases. This
is demonstrated by the good agreement between our simulation results and the
experimental data for both equilibrium and non-equilibrium systems.
The good results for vapour-liquid coexisting phases encourage performing
further computer simulations with realistic potentials. This may improve the
prediction of quantities like critical temperature and density, in particular of
substances for which these properties are difficult to obtain from experiment.
We have demonstrated that use of accurate two- and three-body potentials for
shearing liquid argon and xenon displays significant departure from the
expected strain rate dependencies of the pressure, energy and shear viscosity.
For the first time, the pressure is convincingly observed to vary linearly with an
apparent analytic y2 dependence, in contrast to the predicted y3/2 dependence
of mode -coupling theory. Our best extrapolation of the zero -shear viscosity for
argon gives excellent agreement (within 1%) with the known experimental data.
To the best of our knowledge, this the first time that such accuracy has been
achieved with NEMD simulations. This encourages performing simulations with
accurate potentials for transport properties.
16
Barker, Shaun, and sbarker@eos ubc ca. "Dynamics of fluid flow and fluid chemistry during crustal shortening." The Australian National University. Research School of Earth Sciences, 2007. http://thesis.anu.edu.au./public/adt-ANU20090711.074630.
Повний текст джерелаАнотація:
In this thesis, an integrated structural and chemical approach has been used to investigate the spatial and temporal evolution of fluid chemistry, and fluid flow pathways, during crustal shortening. The Taemas Vein Swarm is hosted in a limestone-shale sequence, the Murrumbidgee Group, in the Eastern Belt of the Lachlan Orogen, in New South Wales, Australia. The Taemas Vein Swarm (TVS) is composed of calcite ± quartz veins, hosted in a series of faults and fractures, which extends over an area of approximately 20 km2. The Murrumbidgee Group is composed of several formations, comprising massive grey micritic limestones, redbed sandstones and shales,and thinly interbedded (1020 cm scale) limestones and shales.
¶
The sedimentary sequence has been folded into a series of upright, open to close
folds, and was probably deformed during either mid-late Devonian, or early Carboniferous, crustal shortening. To the east, the Murrumbidgee Group is overthrust
by a Silurian volcanic sedimentary sequence along the Deakin-Warroo Fault System.
Crosscutting and overprinting relationships demonstrate that vein growth was synchronous with folding, with different vein types related to different fold mechanisms
at various stages of fold growth.
¶
Flexural slip folding led to the development of bedding-concordant veins (hereafter
called bedding-parallel veins). Flexural flow in semicompetent to incompetent beds
caused en echelon extension vein arrays to grow. Decoupling between beds, and
dilatancy at fold hinges led to significant vein growth. In addition, fold lock-up led to
limb-parallel stretching, and the growth of bedding-orthogonal extension fractures.
¶
Vein growth is inferred to have occurred in a compressional tectonic regime (i.e.
sigma3=vertical). Oxygen isotope quartz-calcite thermometry suggests that veins formed at temperatures of 100200 oC. The depth of vein formation may have been between
about 5 and 8 km. Vein textures indicate that growth of veins occurred during
multiple cycles of permeability enhancement and destruction. Subhorizontal extension
fractures, and faults at unfavourable angles for reactivation, imply that fluid
pressures exceeded lithostatic levels during the growth of some veins. Coexisting
extension and shear fractures imply that differential stress levels varied over time.
¶
Flexural slip continued throughout folding at Taemas, despite some fold limbs
being at angles extremely unfavourable for reactivation ( > 60). As folds approached
frictional lock-up, flexural slip continued to occur when supralithostatic fluid pressures were developed. Therefore, large, bedding-discordant faults were not
developed to accommodate strain during folding, explaining a deficiency of larger
faults in the TVS.
¶
Infiltration of overpressured fluids occurred into the base of the Murrumbidgee
Group, and was channelled into a distributed mesh of small faults and fractures.
At the point that a connected backbone flow network developed in the TVS, highpressure
fluids would no longer be available to allow continuing flexural slip on fold
limbs approaching lockup. Thereafter, larger faults would develop, which would
adjust the fault population in the TVS to a more typical displacement-frequency
distribution. This had not occurred in the Taemas area by the time crustal shortening
ceased. An abundance of small faults, and fracturing driven by invasion of
overpressured fluid, implies that the TVS formed via an earthquake swarm process.
¶
Modern analytical techniques, utilising laser ablation sampling technology, allow
high-spatial resolution chemical data to be collected from syntectonic veins. Insights
into the role that fluid-mineral interface processes may have on the chemistry of minerals grown in syntectonic veins were provided by an experimental study. Moderate sized ( < 1−5 mm) synthetic calcite crystals were successfully grown to investigate the uptake of rare earth elements (REE) into calcite. Changes in crystal morphology are linked to variable solution chemistry, which has important implications for the interpretation of hydrothermal vein textures. High-spatial resolution chemical analyses of synthetic calcite crystals demonstrate significant fluctuations in REE concentrations over distances of < 200 μm within calcite crystals. Time-equivalent regions on different crystal faces have significantly different REE concentrations,
indicating that fluctuations in calcite trace element composition cannot be interpreted
exclusively in terms of changing bulk fluid composition. Rare earth element
anomalies (Eu/Eu* and Ce/Ce*) are not significantly influenced by compositional
zoning, and may be robust indicators of changes in solution bulk chemistry and fluid
oxidation state.
¶
Changes in isotopic ratios (13C, 18O and 87Sr/86Sr), and trace element concentrations in veins from the TVS are related to variations in fluid source, flow pathways and chemical conditions (e.g. trace element complexation, precipitation rate, fluid oxidation) during hydrothermal fluid flow. This integrated structural, textural and chemical approach has direct application to the examination of hydrothermal veins
in fracture-hosted ore deposits, and may allow the fluid source and/or chemical
conditions conducive to the formation of high-grade ore to be discerned.
¶
Vein 18O compositions systematically increase upwards through the Murrumbidgee
Group, caused by progressive reaction of an externally derived, low-18O fluid (of
probable meteoric origin) with host limestones. Vein 18O and 87Sr/86Sr compositions vary spatially and temporally within the same outcrop, and within individual veins, which is inferred to be caused by the ascent of packages of fluid along constantly changing flow pathways. Fluid-buffered oxygen isotope ratios at the earliest stages of deformation imply that the TVS formed via an invasion percolation process. Fluid pathways are inferred to have changed constantly, with fractures toggleswitching between high-permeability and low-permeability states, due to repeated
fracture opening and sealing events.
17
Kandah, Munther. "Particles emission control at graphite cathode in arc ion plating deposition." Thesis, McGill University, 1997. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=35434.
Повний текст джерелаАнотація:
In this work, the dependence of the vacuum arc spot velocity on physical and electrical properties of different graphite cathode materials is investigated in the presence of a variable magnetic field. A pulsed arc system is used to perform preliminary experiments on the arc mobility for the different types of graphite for the selection of proper material morphology and the design of a continuous vacuum arc system. The characteristics of arc mobility, erosion rate, and carbon ion flux emitted from the continuous carbon source are then evaluated in view of particle-free diamond-like protective coatings. Results show that the arc spot velocity on graphite cathodes is larger on cathodes having larger grain size, lower electrical resistivity and higher apparent density. The spot velocity is also lower for cathodes having larger pore sizes and total porosity. The arc spot velocity is also found to be increased by increasing the magnetic field intensity over the surface of any graphite type. Reduced residence time of the spot on a given site of the cathode resulting from arc velocity increase should lead to a reduction in the heat load input in the cathode spot. This correlates with results on the number of emitted particles, the film thickness and roughness, and the erosion rate that are found to decrease, while the ion flux emission is increased. Diamond-like carbon (DLC) films free of particles are produced in a continuous arc ion plating (AIP) system. The ion energy in the continuous AIP system is found to vary with the graphite surface properties and the intensity of a plasma confining magnetic field in front of the cathode. The ion energies measured vary between 39.8 eV to 62.6 eV.
18
Kandah, Munther. "Droplets generation mechanisms by graphite cathodes in the vacuum arc deposition technique." Thesis, McGill University, 1993. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=69702.
Повний текст джерелаАнотація:
The most severe problem for the vacuum arc deposition (VAD) technique is the formation of micron-size particles on the films. These particles degrade the films' properties. The present work studied the generation mechanisms and characteristics of the droplets that are produced in the carbon films deposited by vacuum arc technique. To achieve a better control of the generation mechanism of these droplets, the effect of the arc current, arc duration time, cathode spot temperature and distance between cathode and substrate on the size and population of the micro-droplets are studied.The micro-droplets are in the range of 0.3 $ mu$m to 2 $ mu$m in diameter, and have a graphite structure. The most probable origin for these particles are the cathode. The size and population of these particles are directly proportional to the cathode spot temperature (i.e., to the arc current and/or arc duration time), and inversely proportional to the distance between the cathode and the substrate. The droplet production is mainly due to the heating effect.
19
Burrus, Roxanne Grace. "Pharaoh ant consumption of fluids used in hospital environments." [Gainesville, Fla.] : University of Florida, 2004. http://purl.fcla.edu/fcla/etd/UFE0003202.
Повний текст джерела
20
Winter, Amos Greene 1979. "Design of fluid film journal bearings containing continuous 3D fluid pathways which are formed by wrapping a sheet containing 2D through-cut features." Thesis, Massachusetts Institute of Technology, 2005. http://hdl.handle.net/1721.1/33909.
Повний текст джерелаАнотація:
Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2005.Vita.
Includes bibliographical references (leaves 110-112).
The purpose of this research was to generate the knowledge required to: (1) design and manufacture fluid film bearings that do not require precision machining processes during fabrication, but rather gain their precision from off-the-shelf parts used in the fabrication process and (2) manufacture parts with 3D internal networks by wrapping thin sheets of material containing 2D through-cut features. This wrapping-based fabrication process, called Three-Dimensional Wrapped Network (3DWN) technology, uses the precision of low-cost, ubiquitous items instead of manufacturing processes to meet the precision requirements of hydrostatic bearings. 3DWN bearings are fabricated by cutting 2D through-cut features into shim stock and then wrapping the shim stock around a precision mandrel. The 2D shim stock features are designed such that they align and form 3D internal networks within the bearing during wrapping. In the final wrapped structure the bore retains the precision diameter of the mandrel and the surface finish of the shim stock, thus meeting the functional requirements of the bearing. This thesis investigates the design and manufacturing of 3DWN hydrostatic bearings.
(cont.) An analytical model was derived to describe the transformation of 3D cylindrical features to 2D through-cut features. Conventional hydrostatic designs and theory were adapted for use in 3DWN bearings. A proof-of-concept was designed, constructed, and tested. Although contact between the shaft and bore was observed during testing, the fluid film stiffness matched theory within 1.6% after accounting for the contact stiffness. The mean bore diameter was measured to be within 0.03% of the mandrel diameter with errors that lie within 5[sigma] of the tolerable error range in the front of the bearing and 2[sigma] in the rear. In a comparison with a conventional hydrostatic bearing of the same size and surface design, the 3DWN cost lOX less.
by Amos Green Winter, V.
S.M.
21
Hill, Katherine I. "DNAPL migration in single fractures : issues of scale, aperture variability and matrix diffusion." University of Western Australia. School of Environmental Systems Engineering, 2007. http://theses.library.uwa.edu.au/adt-WU2008.0003.
Повний текст джерелаАнотація:
[Truncated abstract] To date, many subsurface contaminant modelling studies have focused on increasing model complexity and measurement requirements to improve model accuracy and widen model application. However, due to the highly complex and heterogeneous nature of flow in the subsurface, the greater benefit in model development may lie in decreasing complexity by identifying key processes and parameters, simplifying the relationships that exist between them, and incorporating these relationships into simple models that recognise or quantify the inherent complexity and uncertainty. To address this need, this study aims to identify and isolate the key processes and parameters that control dense nonaqueous phase liquid (DNAPL) and aqueous phase migration through single, onedimensional fractures. This is a theoretical representation which allows the study of processes through conceptual and mathematical models. Fracture systems typically consist of multiple two-dimensional fractures in a three-dimensional network; however, these systems are computationally and conceptually demanding to investigate and were outside of the scope of this study. This work initially focuses on DNAPL migration in single, one-dimensional fractures. The similitude techniques of dimensional and inspectional analysis are performed to simplify the system and to develop breakthrough time scale factors. This approach relies heavily on the limitations of the equation used for the analysis and on the difficulty in representing variable aperture scenarios. The complexity of the conceptual model is then increased by embedding the fracture in a two-dimensional, porous matrix. ... These tools can be readily applied by the field investigator or computer modeller to make order-of-magnitude estimates of breakthrough times, reduce or target measurement requirements, and lessen the need to employ numerical multiphase flow models. To determine the implications of the results found in the one-dimensional studies to applications at the field scale, the complexity of the conceptual model was increased to a single, two-dimensional, planar fracture embedded in a three-dimensional porous matrix. The focus of this study was not DNAPL breakthrough times but the relative importance and interaction of different mass transport processes and parameters on plume migration and evolution. Observations clearly show that estimates of the size, location and concentration of the plume is highly dependent on the geologic media, the temporal and spatial location and resolution of measurements, and on the history, mass and location of the DNAPL source. In addition, the processes controlling mass transport (especially matrix diffusion and back diffusion) act in combination at the field scale in ways not always expected from an analysis of processes acting individually at smaller spatial and temporal scales. Serious concerns over the application of the common '1% Rule of Thumb' to predict DNAPL presence and the use of remediation efforts that rely largely on natural attenuation are raised. These findings have major implications for the field worker and computer modeller, and any characterisation, monitoring or remediation program development needs to be sensitive to these findings.
22
Polton, Richard. "Numerical grid generation and its application in the solution of a model of the Vacuum-Arc Remelting (VAR) process." Thesis, University of Southampton, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.323918.
Повний текст джерела
23
Meier, David Alan. "The Design and Evaluation of a High Frequency Fore-Aft Probe." Thesis, Virginia Tech, 1997. http://hdl.handle.net/10919/35650.
Повний текст джерелаАнотація:
A high-frequency surge and stall sensing fore-aft probe was developed at the Turbomachinery Research Laboratory at Virginia Tech. The probe was designed to detect surge and stall based on changes in large regions of flow behind a turbofan engine compressor fan. The probe exhibited excellent frequency response capabilities and can accurately measure data with response well above anticipated surge frequencies.
A CFD analysis was performed in order to gain more understanding about the flow around the probe. The results of the CFD analysis and the experimental testing were analyzed and presented. The probe worked as expected when the flow was aligned with the upstream pressure transducer. Thus, it can be used to determine the onset of surge and stall. However, the probe was found to be extremely sensitive to off-axis flows. Design improvements are suggested in order to increase its capabilities.Master of Science
24
Zhou, Alexander [Verfasser], and Wolfgang [Akademischer Betreuer] Arlt. "Explicit Non-Random Contribution in Lattice Fluid Equation of State / Alexander Zhou. Betreuer: Wolfgang Arlt." Erlangen : Universitätsbibliothek der Universität Erlangen-Nürnberg, 2013. http://d-nb.info/1032394102/34.
Повний текст джерела
25
Kudo, Shigetada, and n/a. "Fluid forces on an accelerating hand in swimming." University of Otago. School of Physical Education, 2007. http://adt.otago.ac.nz./public/adt-NZDU20080121.120957.
Повний текст джерелаАнотація:
This study examines the effects of acceleration on fluid forces acting on the hand in swimming and presents a new pressure method to predict fluid forces acting on the accelerating hand.
Swimmers and coaches require accurate information about swimmers� fluid forces, propulsion and drag, in order to improve performance. In general, swimmers are likely to generate propulsion mainly with their hands in the front crawl stroke, butterfly and back crawl stroke. Researchers have attempted to estimate the fluid forces on the hands with various techniques including a cinematographic method (a "quasi-static" approach), a pressure method and a numerical method of computational fluid dynamics. However, the effect of accelerations on fluid forces acting on the hand has not yet been well quantified. Understanding of the effect of acceleration on fluid forces on the hand can provide useful information to enhance swimming performance. Also the developments of a method to predict fluid forces acting on the accelerating hand in swimming can be used to evaluate swimming performance more accurately. The present study used a hand model attached to a load cell to measure forces in three orthogonal directions and pressure sensors to measure pressures on the hand model rotated in the flume. The model position was measured by a potentiometer fixed to the axis of the model rotation.
The quantification of the effect of acceleration was based on a simple theoretical understanding for fluid mechanics, using the inertia coefficients and the coefficients of fluid forces, that is widely accepted in other disciplines. The quantification was focused mainly in the direction tangential to the model rotation because the magnitude of the velocity changed in this direction. The overall effect of acceleration on fluid forces on the hand model was that the inertia coefficients increased rapidly in the early phase of the model movement, then in the final deceleration phase of model movement the inertia coefficients decreased to a negative value and then became small. The inertia coefficient increased in the impulsive start of the hand model, indicating that fluid forces acting on the hand increased as accelerations of the hand increased. This result was consistent with the simple theoretical understanding to induce additional fluid forces on the hand, that is, fluid forces on the hand increased as accelerations increased. However, the inertia coefficient decreased and reached large negative values in the late phase of the model movement involving decelerated motion, indicating that fluid forces on the hand increased as acceleration of the hand decreased to negative values (decelerations). That result was not consistent with the simple theoretical understanding to induce additional fluid forces on the hand because the simple theoretical understanding cannot take account of the preceding history of the fluid motion around the hand model associated with the formation of vortices. Thus, more sophisticated theory is needed. The dynamic pressure measured by the pressure sensors implied that the induced fluid forces might be due to large attached vortices behind the hand model.
The hand was considered as a blunt body when the angle of attack was large (maximum = 90�) and an aerofoil shape when the angle of attack was small. The inertia coefficients became large when the hand model was set at the large angles of attack, indicating that the effect of accelerations on the hand model increased when the hand surface was directed to the on-coming flows (blunt body).
For the development of the new pressure method, a regression analysis was used to build a single best-fit equation to predict fluid forces acting on the accelerating hand model. The single best-fit equation was acquired for various orientations of the hand model. The accuracy of prediction of fluid forces acting on the accelerating hand model was checked by a root mean square (RMS) difference. The RMS difference by the pressure method was approximately half of the RMS difference by the "quasi-static" approach that has been a major method to predict fluid forces exerted by the hand in swimming.
The present study has quantified the effect of acceleration on fluid forces acting on the hand in swimming and developed a new pressure method including acceleration effects to predict fluid forces acting on the accelerating hand.
26
Paulson, Benjamin D. DeBari Susan M. "Magmatic processes in the Jurassic Bonanza arc : insights from the Alberni region of Vancouver Island, Canada /." Online version, 2010. http://content.wwu.edu/cdm4/item_viewer.php?CISOROOT=/theses&CISOPTR=331&CISOBOX=1&REC=3.
Повний текст джерела
27
Coulombe, S. (Sylvain). "A model of the electric arc attachment on non-refractory (cold) cathodes /." Thesis, McGill University, 1997. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=34710.
Повний текст джерелаАнотація:
In this work, a physical model describing the electric arc attachment on electron emitting non-refractory (cold) cathodes is developed and applied to Cu, Fe and Ti cathodes. The model considers the possibility of a pressure build up in the cathode region due to the strong vaporization of the cathode, the formation of a cathode sheath according to the Bohm's model, and the ion-enhanced thermo-field emission of electrons by the cathode surface. The self-sustaining operating conditions of the discharge are defined by two simple criteria based on particle and energy balance considerations. Results clearly show the necessity of having high local metallic vapor pressures in the cathode region of non-refractory cathodes in order to have a self-sustaining arc attachment. A minimum pressure of at least 19 atm is needed for a Cu cathode. This minimum pressure is shown to decrease as the cathode material boiling temperature increases according to an exponential decay law. Current densities of the order of 1010 A m--2 are maintained at the surface of a Cu cathode mainly by the emitted electrons. A comparison of the three different models for the electron emission current found in the literature allowed to define the limits of validity of each model for two typical arc-cathode interaction systems, and to evaluate the underestimation made on the emission current density when a less appropriate model is used. This underestimation is shown to cause an overestimation of important parameters such as the cathode surface temperature and metallic vapor pressure in the cathode region. An analysis of the mechanisms of heat transfer to the cathode surface allowed to show that the confinement of the cathode spot plasma forming the arc attachment could favor the production of vapors to the detriment of liquids. Such a phenomenon is of importance in Arc Ion Plating for instance. Heat losses by conduction in the cathode bulk larger than 1010 W m--2 are shown to favor the formation of liquid
28
Markgren, Jakob. "CFD Modelling of Pressure-control Devices in Substations." Thesis, Umeå universitet, Institutionen för fysik, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-96455.
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29
McIntyre, Lauralyn Ann. "Are fluid resuscitation strategies associated with hospital mortality in severely septic patients? A retrospective cohort study." Thesis, University of Ottawa (Canada), 2005. http://hdl.handle.net/10393/26977.
Повний текст джерелаАнотація:
Background. Fluid resuscitation is the foundation of severe sepsis management as it is a key factor for optimizing cardiac output, and hence restoring hemodynamic stability and perfusion to the tissues.
Objective. To examine for the association between quantity (primary), type (secondary) and method (secondary) of fluid administered in the first six hours after the identification of severe sepsis and hospital mortality.
Conclusion. In this retrospective cohort study, quantity and type of fluid administered in the first six hours after the identification of severe sepsis were not associated with hospital mortality. However, there was a trend toward a reduction in hospital mortality for the group that received fluid boluses and fluid infusions as compared to fluid infusions alone. Future research is required to determine optimal fluid resuscitation practices for patients with severe sepsis.
30
Brooks, Geoffrey Lance. "Coelomic Fluid Protein Profile in Earthworms Following Bacterial Challenge." Thesis, University of North Texas, 2006. https://digital.library.unt.edu/ark:/67531/metadc5476/.
Повний текст джерелаАнотація:
Proteomic techniques were used to evaluate the protein profile of the earthworm, (Lumbricus terrestris), following a bacterial challenge. One control group received no injection; a second control group received injections of phosphate buffer solution (PBS). The experimental group received injections of PBS containing (Aeromonas hydrophila). After incubation for 12 hours at 20°C, coelomic fluid was collected from each group for analysis by 2-D electrophoresis. There were significant differences in spot appearance and density between control and experimental groups. Sixteen spots showed a two-fold increase in density and 63 showed at least a two-fold decrease in density between samples from control and bacteria-challenged earthworms, respectively, suggesting up- and down-modulation of proteins potentially involved in the earthworm's response to bacterial challenge.
31
Choo, (Roland) Tuck Chow. "Mathematical modelling of heat and fluid flow phenomena in a mutually coupled welding arc and weld pool." Thesis, Massachusetts Institute of Technology, 1991. http://hdl.handle.net/1721.1/13688.
Повний текст джерелаАнотація:
Thesis (Sc. D.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 1991.Vita.
Includes bibliographical references (leaves 256-261).
by Tuck Chow Choo (Roland).
Sc.D.
32
Chan, Weng Yew, and chanwengyew@gmail com. "Simulation of arterial stenosis incorporating fluid-structural interaction and non-Newtonian blood flow." RMIT University. Aerospace, Mechanical and Manufacturing Engineering, 2006. http://adt.lib.rmit.edu.au/adt/public/adt-VIT20070108.164458.
Повний текст джерелаАнотація:
The aim of this study is to investigate the fluid-structural response to pulsatile Newtonian and non-Newtonian blood flow through an axisymmetric stenosed vessel using FLOTRAN and ANSYS. This is to provide a basic understanding of atherosclerosis. The flow was set to be laminar and follows a sinusoidal waveform. The solid model was set to have isotropic elastic properties. The Fluid-Structural Interaction (FSI) coupling was two-way and iterative. Rigid and Newtonian cases were investigated to provide an understanding on the effects of incorporating FSI into the model. The wall expansion was found to decrease the axial velocity and increase the recirculation effects of the flow. To validate the models and methods used, the results were compared with the study by Lee and Xu [2002] and Ohja et al [1989]. Close comparisons were achieved, suggesting the models used were valid. Two non-Newtonian models were investigated with FSI: Carreau and Power Law models. The Carreau model fluid behaviour was very close to the Newtonian model. The Power Law model produced significant difference in viscosity, velocity and wall shear stress distributions. Pressure distribution for all models was similar. In order to quantify the changes, Importance Factor (IG) was introduced to determine the overall non-Newtonian effects at two regions: the entire flow model and about the vessel wall. The Carreau model showed reasonable values of IG whereas the Power Law model showed excessive values. Transient and geometrical effects were found to affect the Importance Factor. The stress distributions for all models were found to be similar. Highest stress occurred at the shoulders of the stenosis where a stress concentration occurred due to sharp corners of the geometry and large bending moments. The highest stresses were in the axial direction. Notable circumferential stress was found at the ends of the vessel. Carreau model produced slightly higher stresses than the other models. Wall stresses were found to be primarily influenced by internal pressure, rather than wall shear stresses.
33
Inthavong, Kiao, and kiao inthavong@rmit edu au. "Simulation of Fluid Dynamics and Particle Transport in a Realistic Human Nasal Cavity." RMIT University. Aerospace, Mechanical and Manufacturing Engineering, 2008. http://adt.lib.rmit.edu.au/adt/public/adt-VIT20081202.162555.
Повний текст джерелаАнотація:
Airflow and particle transport through the nasal cavity was studied using Computational Fluid Dynamics (CFD). A computational model of the human nasal cavity was reconstructed through CT scans. The process involved defining the airway outline through points in space that had to be fitted with a closed surface. The airflow was first simulated and detailed airflow structures such as local vortices, wall shear stresses, pressure drop and flow distribution were obtained. In terms of heat transfer the differences in the width of the airway especially in the frontal regions was found to be critical as the temperature difference was greatest and therefore heating of the air is expedited when the air is surrounded by the hotter walls. Understanding the effects of the airway geometry on the airflow patterns allows better predictions of particle transport through the airway. Inhalation of foreign particles is filtered by the nasal cilia to some degree as a defence mechanism of the airway. Particles such as asbestos fibres, pollen and diesel fumes can be considered as toxic and lead to health problems. These particles were introduced and the effects of particle morphology were considered by customising the particle trajectory equation. This mainly included the effects of the drag correlation and its shape factor. Local particle deposition sites, detailed deposition efficiencies and particle trajectories were obtained. High inertial particles tended to be filtered within the anterior regions of the cavity due to a change in direction of the airway as the air flow changes from vertical at the inlet to horizontal within the main nasal passage. Inhaled particles with pharmacological agents are often deliberately introduced into the nasal airway with a target delivery. The mucous lined airway that is highly vascular provides an avenue for drug delivery into the blood stream. An initial nasal spray experiment was performed to determine the parameters that were important for nasal spray drug delivery. The important parameters were determined to be the spray angle, initial particle velocity and particle swirl. It was found that particles were formed at a break-up length at a cone diameter greater than the spray nozzle diameter. The swirl fraction determined how much of the velocity magnitude went into a tangential component. By combining a swirling component along with a narrow spray into the main streamlines, greater penetration of larger particles into the nasal cavity may be possible. These parameters were then used as the boundary conditions for a parametric study into sprayed particle drug delivery within the CFD domain. The results were aimed to assist in the design of more efficient nasal sprays.
34
Brown, Clifford A. "Simulation of the Localized Arc Filament Plasma Actuators for Jet Excitation." University of Akron / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=akron1270860381.
Повний текст джерела
35
Tedeschi, Raffaella. "L'impressionismo di Octave Mirbeau: un'estetica del fluido." Doctoral thesis, Università di Catania, 2012. http://hdl.handle.net/10761/1235.
Повний текст джерелаАнотація:
Il nostro percorso copre l ultimo ventennio del XIX secolo. In un contesto ora definito decadente, ora caratterizzato da un fermento di idee, situiamo la figura di Octave Mirbeau, critico d arte, romanziere, drammaturgo, saggista, del quale evidenziamo lo stretto legame tra le sue idee in ambito artistico e la sua poetica.
Dopo un rapido schizzo della storia della critica d arte ed una panoramica della ricezione dell opera impressionista in Francia, ci concentriamo sull estetica di Octave Mirbeau, che tentiamo di snocciolare dalla lettura delle sue cronache artistiche.
Dopo aver constatato la difficile delimitazione del gruppo impressionista e avendo avanzato una proposta di revisione della nozione di impressionismo letterario, valutiamo l influenza dei commentari d arte sulla produzione romanzesca mirbelliana degli anni Ottanta e Novanta. A tal proposito, ci concentriamo sui romanzi Le Calvaire (1886), L Abbé Jules (1888) e Sébastien Roch (1890), all interno dei quali notiamo l impiego di modalità descrittive influenzate dalla pratica della critica dell arte impressionista. In particolare, l attenzione alla luce ed agli aspetti indistinti del paesaggio, dove si riscontra una fusione degli elementi (acqua, luce, vapore), testimonia tale contaminazione.
In seguito analizziamo il romanzo Dans le ciel, comparso en feuilleton tra 1892 e 1893 alla luce della nozione di fluidità, che ci pare fondare l estetica impressionista, collegandola tanto al simbolismo quanto alla filosofia di Bergson. A tal fine, interroghiamo la mobilità di senso, la dinamica tra presenza ed assenza delle immagini, la dissoluzione della personalità dei personaggi ed il perdersi della parola nel silenzio.
36
Costello, Michael John. "Shell-side fluid dynamics and mass transfer through hollow fibre membrane modules." [Sydney : University of New South Wales], 1995. http://www.library.unsw.edu.au/~thesis/adt-NUN/public/adt-NUN1999.0043/index.html.
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37
Skidmore, F. W., and n/a. "The influence of gas turbine combustor fluid mechanics on smoke emissions." Swinburne University of Technology, 1988. http://adt.lib.swin.edu.au./public/adt-VSWT20070420.131227.
Повний текст джерелаАнотація:
This thesis describes an experimental program covering the development of certain
simple combustion chamber modifications to alleviate smoke emissions from the
Allison T56 turboprop engines operated by the Royal Australian Air Force.
The work includes a literature survey, smoke emission tests on two variants
of the T56 engine, flow visualisation studies of the combustion system in a
water tunnel and combustion rig tests of a standard combustor and four possible
modifications. The rig tests showed that reductions in smoke emissions of
80% were possible by simple modifications that reduced the primary zone
equivalence ratio and improved mixing in that zone.
38
Javidi, Shirvan Alireza. "Modelling of Electric Arc Welding : arc-electrode coupling." Licentiate thesis, Högskolan Väst, Avd för maskinteknik, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:hv:diva-5826.
Повний текст джерелаАнотація:
Arc welding still requires deeper process understanding and more accurateprediction of the heat transferred to the base metal. This can be provided by CFD modelling.Most works done to model arc discharge using CFD consider the arc corealone. Arc core simulation requires applying extrapolated experimental data asboundary conditions on the electrodes. This limits the applicability. To become independent of experimental input the electrodes need to be included in the arcmodel. The most critical part is then the interface layer between the electrodesand the arc core. This interface is complex and non-uniform, with specific physicalphenomena.The present work reviews the concepts of plasma and arc discharges that areuseful for this problem. The main sub-regions of the model are described, andtheir dominant physical roles are discussed.The coupled arc-electrode model is developed in different steps. First couplingsolid and fluid regions for a simpler problem without complex couplinginterface. This is applied to a laser welding problem using the CFD softwareOpenFOAM. The second step is the modelling of the interface layer betweencathode and arc, or cathode layer. Different modelling approaches available inthe literature are studied to determine their advantages and drawbacks. One ofthem developed by Cayla is used and further improved so as to satisfy the basicprinciples of charge and energy conservation in the different regions of thecathode layer. A numerical procedure is presented. The model, implementedin MATLAB, is tested for different arc core and cathode conditions. The maincharacteristics calculated with the interface layer model are in good agreementwith the reference literature. The future step will be the implementation of theinterface layer model in OpenFOAM.
39
Diehl, Alexander [Verfasser], Wolfgang [Akademischer Betreuer] Bach, Wolfgang [Gutachter] Bach, and Colin [Gutachter] Devey. "Causes for variable hydrothermal vent fluid compositions in intraoceanic arcs : insights from fluid compositions and mineral precipitates of the South Kermadec Arc / Alexander Diehl ; Gutachter: Wolfgang Bach, Colin Devey ; Betreuer: Wolfgang Bach." Bremen : Staats- und Universitätsbibliothek Bremen, 2019. http://d-nb.info/1179350030/34.
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40
Bonson, Christopher G. "Fracturing, fluid processes and mineralisation in the Cretaceous continental magmatic arc of Northern Chile (25°15'-27°15'S)." Thesis, Kingston University, 1998. http://eprints.kingston.ac.uk/20612/.
Повний текст джерелаАнотація:
The structural geology of the Coastal CordiIIera of northern Chile (25°15'-27°15'S) is dominated by three fracture systems: (1) the margin-parallel, trench-linked Atacama Fault Zone (AFZ), (2) a northwest¬trending network of faults, and (3) northeast-trending discrete fracture zones. The margin-oblique fracture sets appear to relate to magnetic fabrics imaged deep in the lithosphere and suggests that these fault zones utilise long-lived zones of weakness. The interaction of these fractures was an important structural control on the focusing of melts and ore fluids' in the leading edge of the Andean margin. Magnetite-dominated deposits comprise one major style of genetically-related mineral deposits within the study area. Primary' fluids from a magnetite-apatite deposit (Carmen) are moderate to highly saline (c. 17 to 37wt% NaCl eq.), Na-Ca-Fe±Mg-Cl-H20 brines. Magnetite from the main-stage of mineralisation was precipitated from a fluid with a high alSo content of circa lO%lIvs SMOW, at temperatures of -300 to 500°C and a mean depth of -2.5km, indicating a magmatic provenance of these magnetite deposits. Comb and dendritic textures indicate precipitation from a low viscosity ore fluid, consistent with fluid densities of 0.9 to 1.lg/cm3 and high contents of Cl, F and H20. These data point to a submagmatic origin of the ores. The second major type of fracture-controlled mineralisation in the Coastal CordiIIera are fault-hosted veins and breccia-pipes of specular haematite-cha1copyrite ore. They are found in close spatial relationship with magnetite-dominated styles of mineralisation and are thought to have formed by cooling and oxidation of an originally magnetite-bearing ore fluid, by mixing with a carbonate-bearing, extraneously sourced fluid. This explains the intergrowth of ore minerals with calcite and/or siderite, and the geological setting of these deposits, under a carbonate-precipitating, shallow-marine marginal basin, which is tentatively suggested to source the extraneous fluid. Further investigation is needed to confirm this. A first-order structural control on the distribution of magnetite-dominated deposits is imposed by the Atacama Fault Zone, due to its role in the emplacement of dioritic and granodioritic magmas, which are the likely sources of the magnetite-mineralisation. Magnetite-dominated deposits were emplaced along broadly north-south-trending brittle and mylonitic segments of the sinistral AFZ. The structural controls on the mineralisation imposed by brittle faults are not fully understood. In several of the larger deposits, east¬northeast-fractures are important, although their precise role remains obscure. Magnetite-dominated mineralisation along the mylonitic shear zones of the AFZ and Chivato Fault Zone, appear associated with cyclic deformation. This is linked to pulses of hydrothermal fluids expelled from an intrusion, or episodic fluid flow accompanying high coseismic strain rates, experienced by the mylonites due to their high crustal level. The structural control on the haematite-cha1copyrite breccias is imposed by northwest trending faults. Breccia-pipes and veins are located in dilationaI sites along these faults, such as jogs and/or fault bends. Their textures may also interpreted to relate to the earthquake cycle. Along the AFZ belt of brittle and mylonitic shear zones, haematite-cha1copyrite-bearing, northwest-trending fractures commonly cross-cut the north-south oriented, magnetite bodies. This represents a change in the predominant structures which focused hydrothermal fluids throughout the evolution of a mineralising system. A model is proposed in which, 'locking-up' of the mylonite occurs as the temperature passes through the quartz plastic-brittle transition temperature (-300°C). This causes deformation to switch from localised displacements along the mylonitic shear zones of the AFZ, to more distributed deformation along 'basement-controlled' northwest faults. These faults are more favourable to accommodate displacements due to their orientation and that they are probably nucleated upon inherited zones of crustal weakness. The temperature of the brittle-ductile transition is approximately intermediate between the formation temperatures of the two classes of Fe-oxide deposit, hence switching of the fracture kinematics is broadly contemporaneous, with the change in mineralisation style.
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Piccoli, Martina. "Mouse amniotic fluid stem cells are able to differentiate into satellite cells replenishing the depauperated muscle stem cell niche." Doctoral thesis, Università degli studi di Padova, 2013. http://hdl.handle.net/11577/3423564.
Повний текст джерелаАнотація:
Introduction: Stem cell biology has received much interest because of its potential in both therapeutic application and in vitro modeling of diseases. In particular embryonic stem cells have good proliferative and differentiative abilities, but their use is still associated to ethical concerns and problems related to their teratogenic potential. Adult stem cells have also been described to be pluripotent both in vitro and in vivo. However, their use is limited because they are difficult to isolate and expand, particularly in a clinical setting. In this scenario, it would be advantageous to obtain a cell population with high selfrenewal and differentiation capacities, without ethical problems. In 2007 our group described that amniotic fluid stem (AFS) cells could be derived selecting amniocytes using c-Kit antibody. AFS cells have clonogenic capability and can be directed into a wide range of cell types representing the three primary embryonic lineages.
Aim: This work aiming at characterize the myogenic potential of mouse AFS cells using a mouse model of spinal muscular atrophy and in particular at analyzing their ability to differentiate into satellite cells and colonize the muscle stem cell niche.
Materials and Methods: Mouse AFS cells were obtained by amniocentesis and selected for the marker c-Kit with immunomagnetic beads. Freshly isolated AFS cells were analyzed for the expression of different markers (CD90, CD45, CD44, CD34, CD31, Flk1, SCA1, CD105) by flow cytometry and the expression of Oct4, Sox2, c-Myc, Klf4 and Sca-1 by qRT-PCR at different embryonic stages. For the treatment of HSA-Cre, SmnF7/F7 mutant mice, GFP+ AFS cells were injected via the tail vein and animals were sacrificed one and fifteen months after transplantation. Clinical aspects were observed and analyzed after transplantation to evaluate AFS cells’ effects. Several muscles were stained with hematoxylin and eosin, Masson’s trichrome and analyzed by immunofluorescence with anti-GFP and anti-dystrophin antibodies. To demonstrate the ability of AFS cells to replenish the muscle niche, staining for satellite cell markers and secondary transplantation were performed. The myogenic potential of AFS cells was also evaluated with transplantation after in vitro expansion.
Results: Mouse AFS cell number changes during the course of gestation. At E12.5 these cells express hematopoietic markers (CD45, CD34, SCA1), mesenchymal markers (CD90, CD105) together with Flk1, CD31 and CD44. Gene expression analysis showed that mouse AFS cells express at low levels Oct4 and Sox2 and at high levels c-Myc and Klf4, whereas they are negative for the expression of myogenic genes.
Mild muscular mutant HSA-Cre, SmnF7/F7 mice die at the age of 10 months and show evident clinical complications such as kyphosis and muscle shrinkage. After transplantation with GFP+ AFS or bone marrow (BM) cells mice survival rate increased by 75% and 50% respectively. Animals treated with AFS cells recovered more than 75% of force compared to the untreated. One month after transplantation, muscles obtained from AFS-treated mice displayed 37% of GFP+ fibers, with very low number of regenerating myofibers (<1%) and normal dystrophin expression. Fifteen months after transplantation BM-treated mice displayed a high number of central nucleated fibers and consistent infiltration of interstitial tissue and no GFP+ myofibers, while AFS-treated mice had a normalized phenotype, close to the same age WT mice, and 58% of the myofibers were GFP+. Similar results were obtained with transplantation of mouse AFS cells expanded in culture.
Discussion: Mouse AFS cells are a heterogeneous population, and their phenotype changes during the course of gestation. At E12.5 they express mesenchymal, hematopoietic and endothelial markers, but most importantly don not express myogenic factors, indicating that no myogenic progenitor cells are present in this stem cell population. When injected in a muscular mutant mouse model, AFS cells showed a myogenic potential, even after long-term transplantation, suggesting an interesting therapeutic potential. They indeed were able to differentiate into satellite cells localizing in the muscle stem cell niche and expressing Pax7, a7integrin and SM/c-2.6, exclusively markers of satellite cell population. Moreover, AFS cells could contribute to the formation of new myofibers even after in vitro expansion.Introduzione: Negli ultimi anni lo studio delle cellule staminali ha suscitato molto interesse, sia per il grande potenziale di queste cellule nelle terapie e applicazioni cliniche, sia come modello di studio in vitro per diversi tipi di malattie. In particolare, le cellule staminali embrionali hanno una elevata capacità proliferativa e di differenziazione, ma il loro utilizzo è ancora associato a problematiche etiche. Anche le cellule staminali adulte possiedono grandi potenzialità differenziative sia in vitro che in vivo, tuttavia il loro utilizzo è limitato in quanto difficili da isolare ed espandere, soprattutto in ambito clinico. In questo scenario sarebbe vantaggioso poter ottenere una popolazione di cellule con elevata capacità di proliferazione e differenziazione, senza dover affrontare però problemi di tipo etico. Nel 2007 il nostro gruppo ha isolato una popolazione di cellule staminali dal liquido amniotico (cellule AFS), utilizzando come marcatore il recettore c-Kit. Queste cellule hanno capacità clonogenica e possono essere dirette a differenziare in una vasta gamma di tipi cellulari appartenenti a tutti e tre i foglietti germinativi. Obiettivo: Questo lavoro mira a caratterizzare il potenziale miogenico delle cellule staminali del liquido amniotico di topo utilizzando un modello murino di atrofia spinale muscolare. In particolare è volto ad analizzare la capacità delle cellule AFS di dare origine a cellule staminali muscolari e colonizzare la nicchia staminale del muscolo scheletrico. Materiali e Metodi: Le cellule AFS sono state ottenute mediante amniocentesi e selezionate per la positività al marcatore c-kit con metodo immmunomagnetico. Appena isolate le cellule AFS sono state analizzate per l'espressione di diversi marcatori (CD90, CD45, CD44, CD34, CD31, Flk1, SCA1, CD105) tramite citometria a flusso; inoltre, attraverso qRT-PCR è stata analizzata l'espressione di Oct4, Sox2, c-Myc, Klf4 e Sca-1 delle cellule AFS isolate a diversi stadi embrionali. Per la terapia di topi transgenici HSA-Cre, SmnF7/F7, le cellule AFS GFP+ sono state iniettate per via sistemica attraverso la vena caudale; gli animali sono stati poi sacrificati a uno e a quindici mesi dopo il trapianto. Sono stati osservati e analizzati alcuni parametri clinici per valutare l’effetto del trapianto cellulare. Diversi muscoli sono stati raccolti ed analizzati con ematossilina e eosina, tricromica di Masson e mediante immunofluorescenza con anticorpi anti-GFP e anti-distrofina. Per dimostrare la capacità delle cellule AFS di colonizzare la nicchia staminale del muscolo, sono state eseguite delle immunofluorescenze per i marcatori specifici delle cellule satelliti e sono stati eseguiti dei trapianti secondari. Il potenziale miogenico delle cellule AFS è stato valutato anche con trapianto dopo espansione in vitro. Risultati: Il numero medio di cellule AFS presenti nel liquido amniotico varia nel corso della gestazione murina; all’età di 12.5 giorni queste cellule sono circa l’1% del totale ed esprimono marcatori ematopoietici (CD45, CD34, SCA1), marcatori mesenchimali (CD90, CD105) unitamente a Flk1, CD31 e CD44. L’analisi di espressione genica ha dimostrato che le cellule AFS esprimono a bassi livelli Oct4 e Sox2 e alti livelli di c-Myc e Klf4, mentre, nonostante la composizione mista di questa popolazione, non è stata rilevata espressione di marcatori o fattori di trascrizione tipici dei precursori muscolari. I topi HSA-Cre, SmnF7/F7 mediamente muoiono all'età di 10 mesi e durante il corso della loro vita mostrano evidenti complicazioni cliniche come una pronunciata cifosi e atrofia a livello muscolare. Dopo il trapianto con cellule AFS GFP+ o con cellule del midollo osseo, il tasso di sopravvivenza di questi animali aumenta rispettivamente del 75% e 50%. Gli animali trattati con cellule AFS hanno recuperato più del 75% della forza rispetto agli animali non trattati. Un mese dopo il trapianto, i muscoli di topi trattati con cellule AFS presentano il 37% di fibre GFP+, un numero molto basso di miofibre rigeneranti (< 1%) ed una normale espressione di distrofina. Quindici mesi dopo il trapianto, gli animali trattati con cellule del midollo osseo mostrano un elevato numero di fibre centro nucleate, un’importante infiltrazione di tessuto interstiziale e nessuna miofibra GFP+, mentre i topi trattati con cellule AFS hanno un fenotipo molto simile a quello di topi sani della stessa età, e il 58% delle miofibre è GFP+. Risultati simili sono stati ottenuti trattando lo stesso modello animale con cellule AFS dopo espansione in cultura. Discussione: Le cellule AFS isolate dal liquido amniotico di topo sono una popolazione eterogenea; queste cellule esprimono marcatori mesenchimali, ematopoietici e marcatori endoteliali. Va evidenziato che, nonostante la composizione mista di questa popolazione staminale, non esistono precursori muscolari al suo interno, e quindi qualunque differenziamento in senso muscolare di queste cellule è dovuto ad una differenziazione delle cellule AFS e non ad una maturazione di cellule già pre-commited. Quando vengono iniettate in un modello di atrofia muscolare, le cellule AFS mostrano un grande potenziale miogenico, anche a lungo termine, dimostrandosi una interessante fonte cellulare per scopi terapeutici. Queste cellule infatti sono state in grado di differenziare in cellule satelliti localizzandosi nella nicchia delle cellule staminali muscolari ed esprimendo Pax7, a7integrina e SM/c-2.6, tutti marcatori esclusivi delle cellule satelliti. Inoltre, le cellule AFS possono contribuire alla formazione di nuove miofibre anche dopo espansione in cultura, aumentando così lo spettro di possibili applicazioni terapeutiche.
42
Wijns, Christopher P. "Exploring conceptual geodynamic models : numerical method and application to tectonics and fluid flow." University of Western Australia. School of Earth and Geographical Sciences, 2005. http://theses.library.uwa.edu.au/adt-WU2005.0068.
Повний текст джерелаАнотація:
Geodynamic modelling, via computer simulations, offers an easily controllable method for investigating the behaviour of an Earth system and providing feedback to conceptual models of geological evolution. However, most available computer codes have been developed for engineering or hydrological applications, where strains are small and post-failure deformation is not studied. Such codes cannot simultaneously model large deformation and porous fluid flow. To remedy this situation in the face of tectonic modelling, a numerical approach was developed to incorporate porous fluid flow into an existing high-deformation code called Ellipsis. The resulting software, with these twin capabilities, simulates the evolution of highly deformed tectonic regimes where fluid flow is important, such as in mineral provinces. A realistic description of deformation depends on the accurate characterisation of material properties and the laws governing material behaviour. Aside from the development of appropriate physics, it can be a difficult task to find a set of model parameters, including material properties and initial geometries, that can reproduce some conceptual target. In this context, an interactive system for the rapid exploration of model parameter space, and for the evaluation of all model results, replaces the traditional but time-consuming approach of finding a result via trial and error. The visualisation of all solutions in such a search of parameter space, through simple graphical tools, adds a new degree of understanding to the effects of variations in the parameters, the importance of each parameter in controlling a solution, and the degree of coverage of the parameter space. Two final applications of the software code and interactive parameter search illustrate the power of numerical modelling within the feedback loop to field observations. In the first example, vertical rheological contrasts between the upper and lower crust, most easily related to thermal profiles and mineralogy, exert a greater control over the mode of crustal extension than any other parameters. A weak lower crust promotes large fault spacing with high displacements, often overriding initial close fault spacing, to lead eventually to metamorphic core complex formation. In the second case, specifically tied to the history of compressional orogenies in northern Nevada, exploration of model parameters shows that the natural reactivation of early normal faults in the Proterozoic basement, regardless of basement topography or rheological contrasts, would explain the subsequent elevation and gravitationally-induced thrusting of sedimentary layers over the Carlin gold trend, providing pathways and ponding sites for mineral-bearing fluids.
43
Nielsen, Torbjörn. "Electric arc-contact interaction in high current gasblast circuit breakers." Licentiate thesis, KTH, Mechanics, 2001. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-1275.
Повний текст джерела
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Shah, Ashish, and ashishshah7@yahoo co in. "Rheology of Shear Thickening Mineral Slurries." RMIT University. Civil, Environmental and Chemical Engineering, 2008. http://adt.lib.rmit.edu.au/adt/public/adt-VIT20080725.133946.
Повний текст джерелаАнотація:
Abstract In order to improve the optimisation of mineral processing operations the rheological properties of slurries must be determined as accurately as possible under the conditions that closely resemble actual site conditions. The rheology of particles suspended in Newtonian fluids is well documented. However, the rheology of particles in non-Newtonian fluids has not been the subject of much investigation till now. The work conducted here attempts to fill this gap in knowledge. The rheological properties of slurries are heavily dependent on the solids concentrations and particle-solid interaction. At low solids concentrations, constant viscosity and Newtonian behaviour is observed, but as solids concentration increases the rheological behaviour becomes increasingly complex and non-Newtonian with viscosity becoming dependent on the shear rate. The nature of the non-Newtonian behaviour depends on the solid concentration, particle shape, particle size, particle size distribution and the suspending liquid rheological properties. The suspension/slurry may develop a yield stress and become time dependent in nature as structures develop within the fluid at higher solids concentrations. This study however, is primarily focused on the measurement of the rheological properties, where it is assumed that the fluid will be fully sheared and that the rheological properties will be unlikely to change with time. Shear thickening behaviour of slurries was the focus of this work. The aim was to investigate the slurry concentration region where shear thickening occurs. The first objective of the project was to develop a fluid analogue which will have similar rheological behaviour to that of concentrated tailings from gold mines so that it can be used as a test material to simulate the flow behaviour of the tailings in a pipe. The second objective of this project was to enable the prediction of flow behaviour in the pipe loop under certain conditions using the fluid analogue for slurry from Sunrise dam. In order to achieve the objectives, experiments were carried out to obtain a fluid analogue of a shear thickening slurry. CSL 500 and SR 200 rheometers were used for the characterisation of different fluid analogues and shear thickening mineral slurries. Malvern Sizer, model: mastersizerX v1.1, was used to obtain particle size distributions. A mini pipe loop system, located in the laboratory of the Rheology and Materials Processing Centre (RMPC) was used to get pipe line flow data for comparison with the rheometer data. A few fluid analogues with different suspending medium and different concentrations of glass spheres was tested before finally using, 48 vol% glass spheres in 1.8 wt% CMC solution as a fluid analogue for the mineral tailings obtained from Sunrise dam, WA. For comparison between the pipe line and rheometer data, all pipe line data (in the form of 8V/D) were converted to rheometer data (in the form of du/dr) using the Robinowitsch-Mooney equation. The above comparison indicated that it is possible to produce fluid analogue to simulate the flow behaviour of Sunrise dam slurry using a shear thinning suspending medium with high concentration of glass particles. Shear thickening flow behaviour was clearly observed in the rheometer while it was less predominant in a pipe line flow.
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Bertling, Wiik Siri. "Whispering Bodies : The Textual Brain." Thesis, Stockholms konstnärliga högskola, Institutionen för scenkonst, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:uniarts:diva-939.
Повний текст джерелаАнотація:
During this project I’ve been exploring how we can work with things within art to change our way of relating to ourselves, other humans and our surrounding. I want to see if finding inner spaces within us can make us feel more connected to our external surrounding. I want to share the feeling of being connected with things through incorporating them inside our own bodies. I have therefore been leading participants on introspective journeys where they found rooms inside of their bodies. After that I have been translating these inner spaces into immersive performative Scenography, where visitors have been invited to engage with the things in the space with all their senses. All the bodies, things as well as visitors, have been given the possibility to interact on their own terms. I wanted to see what kind of relating this room of Whispering Bodies; the Immersive Scenography inspired and invited to, and I wished for it to be a tactile bonding with a sense of heightened empathy and listening. This text-based piece, called Whispering Bodies: The Textual Brain, is created out of a curiosity in how a reflection based in the written language can exist as a complementary work for a physical and tactile space, in this case Whispering Bodies: The Immersive Scenography. I wanted to create an experience that would have traces of the room filled with different bodies. I have been experimenting with how to use different mediums to make this happen, and this piece will be a combination of meditation, video, drawings, audio and text, and the text itself will be jumping in between genres. I want to invite you to take part in this journey with me. It will be dry, it will be poetic, it will be telling you what happened, both the factual and the fictional. If you have any questions, feel free to contact me about the work.
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DeJager-Kennedy, Robin. "Semi-Analytical Analysis of Hand-Arm Vibration and Bench-Top Fluid Flow Test to Understand Vibration Effect on Vascular Disorder." University of Cincinnati / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1282062413.
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Soelberg, Joshua David. "Stability of Basin-Scale Internal Waves Within the South Arm of the Great Salt Lake." DigitalCommons@USU, 2009. https://digitalcommons.usu.edu/etd/372.
Повний текст джерелаАнотація:
The fluid circulation patterns, temperature distributions, and density gradients of the South Arm of the Great Salt Lake were modeled using the Estuary, Lake, and Coastal Ocean Model (ELCOM) from the Centre for Water Research at the University of Western Australia. The effort is part of a research study in conjunction with the United States Geological Survey (USGS) and the Utah Water Research Lab located at Utah State University. The model was simulated for several different cases of salinity gradients over different time periods, using temperature and wind data from 2006. The model is then used to identify factors which may provide a transport mechanism of heavy metals such as selenium and mercury from the sediment layers to the upper brine layers where it is introduced into the food chain.
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Taddese, Tseden. "Thermodynamics and dynamics of polymers at fluid interfaces." Thesis, University of Manchester, 2016. https://www.research.manchester.ac.uk/portal/en/theses/thermodynamics-and-dynamics-ofpolymers-at-fluid-interfaces(27166765-7d8b-405f-90d2-7f2489a200ca).html.
Повний текст джерелаАнотація:
The aim of this thesis is to study the structural and thermodynamical properties of polymers at liquid/liquid interfaces by means of multiscale molecular dynamics simulations. This thesis is presented in alternative format, and the results, consisting of three journal articles, are divided into two main parts. The first part of the thesis looks at the structural and dynamical changes as well as the thermodynamic stability of polymers of varying topology (linear and star-shaped) at interfaces by performing molecular dynamics simulations on model systems. It was found that homopolymers are attracted to the interface in both good and poor solvent conditions making them a surface active molecule, despite not being amphiphilic. In most cases changing polymer topology had only a minor effect on the desorption free energy. A noticeable dependence on polymer topology is only seen for relatively high molecular weight polymers at the interface. Examining separately the enthalpic and entropic components of the desorption free energy suggests that its largest contribution is the decrease in the interfacial free energy caused by the adsorption of the polymer at the interface. Furthermore, we propose a simple method to qualitatively predict the trend of the interfacial free energy as a function of the polymer molecular weight. In terms of the dynamics of a linear polymer, the scaling behaviour of the polymer confined between two liquids did not follow that predicted for polymers adsorbed onsolid or soft surfaces such as lipid bilayers. Additionally, the results show that in the diffusive regime the polymer behaves like in bulk solution following the Zimm model and with the hydrodynamic interactions dominating its dynamics. Further simulations carried out when the liquid interface is sandwiched between two solid walls show that when the confinement is a few times larger than the blob size the Rouse dynamics is recovered. The second part of the thesis focuses on optimizing the MARTINI coarse-grained (CG) Model, which retains certain chemical properties of molecules, to reproduce solubility of polymers, in specific polyethylene oxide (PEO), in both polar and non-polar solvents. Performing molecular dynamics simulations using this CG model will then enable us to study the properties PEO in octanol/water and hexane/water systems with increased length and timescales not accessible by atomistic simulations. The MARTINI CG method (Marrink et al., J. Phys. Chem. B, 2007, 111, 7812) is based on developing the optimal Lennard-Jones parameters to reproduce the partition free energy between water (polar solvent) and octanol (apolar solvent). Here we test the MARTINI CG method when modelling the partitioning properties of PEO, with increasing molecular weight between solvents of different polarity by comparing the results with atomistic simulation. We show that using simply the free energy of transfer from water to octanol to obtain the force parameters does not guarantee the transferability of the model to other solvents. Instead one needs to match the solvation (or hydration) free energies to ensure that the polymer has the correct polarity. We propose a simple method to select the Lennard-Jones parameter to match the solvation free energies for different beads. We also show that, even when the partition coefficient of the monomer is correct, even for modestly high molecular weight of the polymer the predicted partitioning properties could be wrong.
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Zhang, Junfang, and junfang zhang@csiro au. "Computer simulation of nanorheology for inhomogeneous fluids." Swinburne University of Technology. Centre for Molecular Simulation, 2005. http://adt.lib.swin.edu.au./public/adt-VSWT20050620.095154.
Повний текст джерелаАнотація:
In this thesis, we use nonequilibrium molecular dynamics (NEMD) methods to investigate the structural and dynamic properties of highly confined atomic and polymeric fluids undergoing planar Poiseuille flow. We derive 'method of planes' expressions for pressure tensor and heat flux vector for confined inhomogeneous atomic fluids under the influence of three-body forces. Our derivation is validated against NEMD simulations of a confined atomic fluid acted upon
by a two-body Barker-Fisher-Watts force coupled with the Axilrod-Teller three-body force. Our method of planes calculations are in excellent agreement with the equivalent mesoscopic route of integrating the momentum and energy continuity equations directly from the simulation data. Our calculations reveal that three-body forces have an important consequence for the isotropic pressure, but have negligible in�uence on the shear stress and heat flux vector for a confined simple fluid. We use the non-local linear hydrodynamic constitutive model, proposed by Evans and Morriss [1] for computing a viscosity kernel, a function of compact support, for inhomogeneous nonequilibrium fluids. Our results show that the viscosity kernel, �(y),
has a peak at y = 0, and gets smaller and decays to zero as y increases. Physically, it
means that the strain rate at the location where we want to know the stress contributes
most to the stress, and the contribution of the strain rate becomes less significant as the
relative distance y increases. We demonstrate that there is a limitation in the model
when it is applied to our confined fluids due to the effect of domain restriction on inverse
convolution. We study the nanorheology of simple polymeric fluids. Our NEMD simulation results show that sufficiently far from the walls, the radius of gyration for molecules under shear in the middle of the channel follows the power law, Rg / N�, where N is the number of
bonds and the exponent has a value � = 0:60�0:04, which is larger than the melt value
of 0:5 for a homogeneous equilibrium �uid. Under the conditions simulated, we find that
viscous forces dominate the flow, resulting in the onset of plug-like flow velocity pro�les
with some wall slippage. An examination of the streaming angular velocity displays a strong correlation with the radius of gyration, being maximum in those regions where Rg is minimum and vice-versa. The angular velocity is shown to be proportional to half the strain rate su�ciently far from the walls, consistent with the behaviour for homogeneous fluids in the linear regime. Finally, we make some concluding remarks and suggestions for future work in the
final chapter.
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Horko, Michael. "CFD optimisation of an oscillating water column wave energy converter." University of Western Australia. School of Mechanical Engineering, 2008. http://theses.library.uwa.edu.au/adt-WU2008.0089.
Повний текст джерелаАнотація:
Although oscillating water column type wave energy devices are nearing the stage of commercial exploitation, there is still much to be learnt about many facets of their hydrodynamic performance. This research uses the commercially available FLUENT computational fluid dynamics flow solver to model a complete OWC system in a two dimensional numerical wave tank. A key feature of the numerical modelling is the focus on the influence of the front wall geometry and in particular the effect of the front wall aperture shape on the hydrodynamic conversion efficiency. In order to validate the numerical modelling, a 1:12.5 scale experimental model has been tested in a wave tank under regular wave conditions. The effects of the front lip shape on the hydrodynamic efficiency are investigated both numerically and experimentally and the results compared. The results obtained show that with careful consideration of key modelling parameters as well as ensuring sufficient data resolution, there is good agreement between the two methods. The results of the testing have also illustrated that simple changes to the front wall aperture shape can provide marked improvements in the efficiency of energy capture for OWC type devices.