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Laverty, Rory. "Surface tension /". Electronic version (PDF), 2007. http://dl.uncw.edu/etd/2007-1/r1/lavertyr/rorylaverty.pdf.
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Bundy, Penny. "Dramatic Tension: Towards an Understanding of 'Tension of Intimacy'". Thesis, Griffith University, 1999. http://hdl.handle.net/10072/366137.
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This thesis documents my attempts (as a playwright, director and process drama worker) to understand 'tension of intimacy'. It focuses on the questions: What is 'tension of intimacy' in drama? How might it be created? Does the experience of 'tension of intimacy' offer the possibility of new knowledge emerging for the participants and spectators of drama?
The methodology (articulated in Chapter Two) involves reflective practice. This chapter incorporates discussion of the nature of knowledge claims and the way they might be judged. The need for criteria of openness is asserted. The research plan and the reflective journey are outlined. Problems associated with the approach are discussed. In Chapter Three, the premises informing O'Toole's (1992) naming of different types of dramatic tension are discussed. Ryle's and Koestler's (1975) models of emotional response are briefly outlined. The difference between emotional response to life and art, and claims regarding the roles of conflict and expectation in the creation and experience of dramatic tension are considered. The suggestion that dramatic tension relates to questions of identity, power and control is questioned. The chapter concludes with a discussion of the potential links between the experience of emotional engagement in response to drama and the emergence of changed awareness or understanding. In Chapter Four, I discuss 'the nature of intimacy' drawing in particular on the theory developed by Malone and Malone (1987) who (unlike other theorists discussed) separate the notions of intimacy and closeness and consider the way it might be experienced as people encounter, not just humans, but other aspects of existence including art. The defining characteristics of intimacy are articulated as connection, animation and heightened awareness. The 'qualities of intimacy' are defined as free choice, personal integrity, acceptance, personal surrender, self-responsibility, attentiveness, risk-taking, presence, participation and systemic detachment and playfbl engagement. Chapter Five incorporates reflection on dramatic works and real-life situations. This is followed by Chapter Six where I document several unsuccessfbl attempts to create script driven by a 'tension of intimacy'. I conclude by questioning my earlier assumptions. In Chapter Seven, the labels applied by O'Toole (1992) and Haseman & O'Toole (1986) to a range of different types of dramatic tension are reconsidered. Following this, I conclude that my earlier theoretical assumptions about the creation and naming of tensions: (a) are inadequate to account for the way people respond differently to the same dramatic moment (b) fail to recognise that tension is created through aspects other than narrative and determine that: (a) dramatic tension is not contained in the drama but in the spectators and participants as they experience it (c) every source of contrast is a potential cause of dramatic tension and these can emerge from within and external to the work I conclude that 'tension of intimacy' might be created if the defining characteristics and 'qualities of intimacy' are present in a spectator's or participant's response to the experience of contrast. In Chapter Eight, my focus shifts to consider structural devices which offer the possibility of the 'qualities of intimacy' being experienced in response. Irony; figure- ground contrast; ritual; and devices intended to distance, alienate or prolong perception are discussed. In Chapter Nine my process of working as a writerldirector to group devise the play's action is documented. The resultant play, Umbilical Cords and Metronomes, is included as Chapter Ten. The exegesis contained in Chapter Eleven is informed by participant and spectator interviews as well as my own response to the process and product. In conclusion, I discuss the terms connection, animation and heightened awareness as they apply in the experience of drama. Significant aspects influencing 'tension of intimacy' including playful response, trust, perceptions of integrity and individual 'reading' processes are discussed. The link between risk-taking, heightened awareness and the possible emergence of new knowledge is considered. Chapter Twelve begins with a summary of the study. Constraints and implications are then briefly discussed. The chapter (and thesis) concludes by returning to answer the questions originally posed. In conclusion I claim that 'tension of intimacy' names the experience of spectators or participants when the defining characteristics of intimacy (connection, animation and heightened awareness) characterise their response and is created when they experience: a feeling of invigoration or animation as they respond to a contrast or metaxis between the stage action and their real world existence (and) reduced conscious focus on the stage action and heightened awareness of their response to the juxtaposition (and) challenge, rather than affirmation, of earlier assumptions and beliefs. I conclude that trust, perceptions of integrity in the action (and in personal response to it) and playful engagement are prerequisites for this experience.Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Vocational, Technology and Arts Education
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Fields, Kelvin L. "Tension stiffening response of high-strength reinforced concrete tensile members". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape17/PQDD_0002/MQ35492.pdf.
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VALLEJOS, CASTRO GABRIELA. "A Tension Please". Thesis, Högskolan i Borås, Institutionen Textilhögskolan, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-18107.
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This degree work is about the exploration of the stretch in textile materials by using cartridge pleats as a method to create weight and thereby create tension. Through research in materials and stretch fabrics versus heavier woven textiles the work strives for expressions in movement as well as new ways of combining lightness and weight.Program: Modedesignutbildningen
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Snowdon, Roger J. III. "Tension in Space". Kent State University / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=kent1461418173.
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Harvey, Judith Angela Felicia. "Bitumen films in tension". Thesis, University of Cambridge, 2000. https://www.repository.cam.ac.uk/handle/1810/251738.
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Gupta, Surendra K. "Parametric splines in tension /". Online version of thesis, 1989. http://hdl.handle.net/1850/10625.
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Thompson, Alice B. "Surface-tension-driven coalescence". Thesis, University of Nottingham, 2012. http://eprints.nottingham.ac.uk/12522/.
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When fluid droplets coalesce, the flow is initially controlled by a balance between surface tension and viscosity. For low viscosity fluids such as water, the viscous lengthscale is quickly reached, yielding a new balance between surface tension and inertia. Numerical and asymptotic calculations have shown that there is no simply connected solution for the coalescence of inviscid fluid drops surrounded by a void, as large amplitude capillary waves cause the free surface to pinch off. We analyse in detail a linearised version of this free boundary problem. For zero density surrounding fluid, we find asymptotic solutions to the leading order linear problem for small and large contact point displacement. In both cases, this requires the solution of a mixed type boundary value problem via complex variable methods. For the large displacement solution, we match this to a WKB analysis for capillary waves away from the contact point. The composite solution shows that the interface position becomes self intersecting for sufficiently large contact point displacement. We identify a distinguished density ratio for which flows in the coalescing drops and surrounding fluid are equally important in determining the interface shape. We find a large displacement solution to the leading order two-fluid problem with a multiple-scales analysis, using a spectral method to solve the leading order periodic oscillator problem for capillary waves. This is matched to a single-parameter inner problem, which we solve numerically to obtain the correct boundary conditions for the secularity equations. We find that the composite solution for the two-fluid problem is simply connected for arbitrarily large contact-point displacement, and so zero density surrounding fluid is a singular limit.
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Erla, Adamsdóttir Lilý. "Tension Attention! : Dancing Embroidery". Thesis, Högskolan i Borås, Akademin för textil, teknik och ekonomi, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-12400.
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This Master’s degree project explores the design possibilities of thread tension, to create a transformation in an interactive, 3D embroidered, wooden surface. The aim is to create a playful visual expression on a surface triggered by interaction. The surface is manipulated by embroidery and the embroidery is manipulated by the tension in the thread. Together all parts create a simple mechanism that allows the viewer to sink into a playful loop of a rising and collapsing structure. Dancing embroidery. The work explores the potential of the thread as a key factor together with interaction to make a transformation of a surface possible. The thread is used both in the function of the surface and at the same time it creates a strong visual expression as it stands out to show its strength and power.
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Griesser, Arthur F. "U(1) string tension". W&M ScholarWorks, 1991. https://scholarworks.wm.edu/etd/1539623802.
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The long distance force between quarks in the U(1) approximation to quantum chromodynamics is calculated on a home made reduced instruction set computer optimized for that purpose. It is found that previous calculations were in error by as much as 85% due to contamination by the Coulomb interaction. The Coulomb constant, measured for the first time in this work, agrees with analytically obtained values.
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Sakly, Jaouhar. "Influence du filtre d'entrée sur la tension de sortie des onduleurs de tension monophasés". Lille 1, 1991. http://www.theses.fr/1991LIL10154.
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Les onduleurs de tension monophasés sont surtout utilisés dans les alimentations de sécurité et dans les convertisseurs DC-DC à étage intermédiaire alternatif. Dans ces applications, le but est d'obtenir un signal de sortie alternatif sinusoïdal dont l'amplitude et la fréquence peuvent être contrôlées. La tension continue à l'entrée est le plus souvent obtenue par redressement et filtrage de la tension du réseau. L'étude des lois de commande se fait généralement en négligeant les imperfections de la source d'entrée. Le mémoire présente les résultats de l'analyse harmonique de la tension de sortie et du courant pris à la source continue d'entrée, en tenant compte des imperfections de la source d'entrée que les éléments L et C du filtre tentent de compenser. Deux structures d'onduleurs de tension monophasés sont étudiées : le montage en pont complet et le montage en demi-pont à diviseur capacitif. Pour chaque montage, plusieurs stratégies de commande sont appliquées: la commande symétrique, la commande décalée, et la commande en modulation de largeur d'impulsions. Pour chaque stratégie de commande, les résultats de l'analyse harmonique sont présentés, d'abord en considérant le cas d'une inductance de filtrage infinie à l'entrée, puis en tenant compte de la valeur finie de cette inductance. L'étude montre en particulier que pour la commande MLI, l'amplitude de l'harmonique 3 de la tension de sortie est indépendante du nombre d'impulsions composant cette tension de sortie. Les caractéristiques jointes au mémoire permettent de choisir les éléments L et C du filtre d'entrée
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Weitzel, Annegret. "Tension Free Vaginal Tape (TVT)". Diss., lmu, 2007. http://nbn-resolving.de/urn:nbn:de:bvb:19-76515.
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Шевченко, Володимир Порфирович, Владимир Порфирьевич Шевченко, Volodymyr Porfyrovych Shevchenko i І. А. Пустовий. ""Tension free" герніопластика вентральних кил". Thesis, Вид-во СумДУ, 2007. http://essuir.sumdu.edu.ua/handle/123456789/4968.
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Yuan, Xing-Hong. "Simplification des reseaux moyenne tension". Paris 6, 1989. http://www.theses.fr/1989PA066736.
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La tension nominale des reseaux moyenne tension est comprise entre quelques kilovolts et 35 kv. Ces reseaux contiennent tellement d'elements qu'il est le plus souvent necessaire de les simplifier pour effectuer une etude. La simplification, c'est l'elimination ou le regroupement de portions du reseau et le remplacement de celui-ci par un reseau equivalent. Le reseau equivalent doit correspondre a l'original en ce qui concerne les pertes, les chutes de tension aux nuds les plus importants, l'estimation de l'energie non distribuee. . . Mais, simplification signifie approximations et erreurs; celles-ci doivent etre minimisees et, si possible, corrigees. Des methodes de simplification sont utilisees par reduction de la matrice admittance et par d'autres methodes qui modifient la topologie initiale. Des strategies sont proposees pour conduire la simplification. Enfin un logiciel utilisant les concepts developpes a ete ecrit qui permet de tester les methodes sur des exemples pratiques
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Ezanno, Pierre. "Flippase, tension mécanique et mécanosensibilité". Paris 6, 2009. http://www.theses.fr/2009PA066167.
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Membranaires ou solubles, les protéines sont sensibles à leur environnement. La tension mécanique latérale de membrane via les lipides est un paramètre physico-chimique de l’environnement des protéines membranaires. La flippase (une protéine membranaire) peut moduler cette tension en créant une asymétrie de population des lipides entre les deux feuillets d’une membrane. La flippase des érythrocytes (ATPase dépendante du Mg ATP) est, dans cette thèse, utilisée non purifiée : à partir de sa membrane native. Une protéine membranaire mécanosensible change de conformation en fonction de la tension mécanique dans la membrane. Le MscL (Mechano sensitive channel Large conductance) en est un exemple. La flippase reste active dans les systèmes membranaires géants utilisés, malgré une étape de déshydratation partielle de la membrane (étape nécessaire à la formation de liposomes géants). Un ajout de Mg ATP déclenche l’activité flippase qui est détectée par un changement de forme de liposomes. Ensuite, la tension mécanique latérale a été déclenchée dans une membrane qui contient la flippase et aussi le MscL dont le changement de conformation est observé en électrophysiologie. En présence d’activité flippase, le comportement du MscL est modifié : la tension requise d’ouverture semble plus basseMembrane proteins and soluble proteins are sensitive to their environment. The lateral mechanical tension in membrane via lipids is a physico-chemical parameter of membrane protein environment. The flippase (a membrane protein) can modulate this tension creating an asymmetry of lipids populations between both of membrane leaflets. Flippase from erythrocytes (a Mg ATP dependent ATPase) is, in this thesis, used unpurified: from its native membrane. A mechanosensitive membrane protein changes conformation according to the mechanical tension in the membrane; for example, the MscL (Mechano sensitive channel Large conductance). The flippase is still active in giant membrane systems used, despite a partial dehydration step of membrane (required step in making giant liposomes). An addition of MG ATP triggers the flippase activity which is detected by liposome shape changes. Then, the lateral mechanical tension is triggered in a membrane containing the flippase and the MscL the opening of which is monitored by electrophysiology. In the presence of flippase activity, the MscL’s behaviour is modified: the required tension to open the channel seems to be lowered
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Hadidimoud, S. "Modelling local damage and material rupture (using finite element method)". Thesis, University of Surrey, 2000. http://epubs.surrey.ac.uk/998/.
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Zuluaga, Walter. "Effect of Fatigue Cycle Loading Amplitude Tension-Tension on Composite Laminated Plates with Initial Delamination". DigitalCommons@CalPoly, 2013. https://digitalcommons.calpoly.edu/theses/1023.
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Effect of Fatigue Cycle Loading Amplitude Tension-Tension on Composite Laminated Plates with Delamination
Composite materials provide many mechanical advantages; however, they are susceptible to failure or delamination due to impact, high concentrated stresses and fatigue produced by high loading and dripping weight due to poor manufacturing processes yielding to delamination. The objective of enhancing delamination in the laminated composite structural panel’s elements is to control the response of the composite structures in order to prevent catastrophic failure due to excessive deformation. The main scope of this thesis is to study the effect of a different amplitude fatigue cycle in tension-tension on a carbon fiber laminated composite plates with initial delamination to determine the maximum number of loading cycles required to propagate the initial delamination and failure through the preformed delamination. The study also, will encompass the comparison with numerical analysis models using Nastran/Patran software .
The laminate composite plates were fabricated with woven prepreg carbon fiber with an initial delamination and tested under tensile and constant amplitude cycle loading. The tensile characteristics of the laminated composite plates were determined using the standard test. The number of the fatigue cyclic was determined for fatigue tests with different maximum stresses of 72 .5%, 69.5%, 66.5%, 63.5%, and 60.5% from the average ultimate failure loading. A linear static numerical analysis was performed using MSC Patran/Nastran to correlate a finite element model and test data for the tensile load cases. The finite element model was validated by comparing the deformation shape and the predicted high stress concentration areas of the test specimen during the experimental analysis with the predicted numerical analysis.
The flexural stiffness is predicted to be reduced by approximately 200% by the addition of an initial delamination. The fatigue life of the laminated composite plates tested would extend over 20000 cycles at a load rate between 55% and 60% of the ultimate failure loading if the input load drops above 10%. The numerical analysis performed showed a difference of 41% to the experimental analysis.
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Canady, Brittany E. "The effects of regular aerobic exercise on tension headache". Huntington, WV : [Marshall University Libraries], 2002. http://www.marshall.edu/etd/descript.asp?ref=105.
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Imaneini, Hossein. "Analyse et dimensionnement d'un convertisseur modulaire moyenne tension-basse tension pour la conversion isolée à découpage". Grenoble INPG, 2009. http://www.theses.fr/2009INPG0038.
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Ce manuscrit présente une structure modulaire isolée à découpage permettant l'alimentation de charges sensibles à partir du réseau électrique. Elle utilise une topologie multicellulaire abaisseuse, qui se connecte directement sur le réseau moyenne tension. Le secondaire délivre une tension parfaitement régulée pour l'application sensible. L'ensemble de la structure de conversion est composé de trois parties: une mise en série de redresseurs en pont, un étage d'isolation haute fréquence et un onduleur de sortie. La partie redresseurs est commandée en absorption sinusoïdale, et convertit la tension alternative élevée en une tension continue plus faible. Des convertisseurs continu continu isolés sont connectés en parallèle sur ce bus continu et assurent l'iolation galvanique. Enfin, un onduleur triphasé génère l'onde de tension alternative finale visée. Des stratégies de commande originales sont proposées et validées expérimentalement et par simulationIn this dissertation, a modular PET structure is presented for feeding critical loads in the network. The utilized topology is a multi-cellular step-down converter that can directly connect to medium voltage levels on the primary side and provide a low-voltage, highly-stable interface for consumer applications. The presented structure consists of three stages : a Cascaded H-Bridge (CHB) rectifier, an isolation stage, and an output stage. The CHB rectifier serves as an active rectifier to ensure that the input current is sinusoidal, and it converts the high AC input voltage to low DC voltages. The isolated DC/DC converters are then connected to the DC links and provide galvanic isolation between the HV and LV sides. Finally, a three-phase inverter (which can be part of the respective load) generates the AC output with the desires amplitude and frequency. Several new control approaches are presented and verified by simulation and experimental results
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Köster, Darius Vasco. "Role of Caveolae in Membrane Tension". Doctoral thesis, Universitätsbibliothek Leipzig, 2010. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-63103.
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Caveolae sind charakteristische Plasmamembraneinstülpungen, die in vielen Zelltypen vorkommen und deren biologische Funktion umstritten ist. Ihre besondere Form und ihre Häu gkeit in Zellen, die stets mechanischen Belastungen ausgesetzt sind, führten zu der Annahme, dass Caveolae die Plasmamembran vor mechanischen Belastungen schützen und als Membranreservoir dienen. Dies sollte mit dieser Dissertation experimentell geprüft werden. Zunächst wurde der Ein uss der Caveolae auf die Membranspannung von Zellen im Normalzustand untersucht. Dann wurden die Zellen mechanisch belastet. Mit Fluoreszensmikroskopie wurde das Verschwinden von Caveolae nach Strecken der Zellen oder nach einem hypo-osmotischen Schock beobachtet. Messungen der Membranspannung vor und unmittelbar nach dem hypo-osmotischem Schock zeigten, dass Caveolae einen Anstieg der Membranspannung verhindern, unabhängig von ATP und dem Cytoskelett. Die Erzeugung von Membranvesikel mit Caveolae erlaubte es, diesen Effekt der Caveolae in einem vereinfachten Membransystem zu beobachten. Schliesslich wurden Muskelzellen untersucht. Zellen, die genetisch bedingt weniger Caveolae haben und mit Muskelschwundkrankheiten in Verbingung stehen, waren mechanisch weniger belastbar als gesunde Zellen. Zusammenfassend wird mit dieser Dissertation die These bestärkt, dass Caveolae einem Anstieg der Membranspannungen entgegenwirken. Dass dies in Zellen und in Vesikeln unabhängig von Energie und Cytoskelett geschieht, lässt auf einen passiven, mechanisch getriebenen Prozess schliessen. Diese Erkenntnis trägt zum Verständnis der Rolle von Caveolae in Zellen bei und kann dem besseren Verständnis von Krankheiten bedingt durch Caveolin-Mutationen, wie z.B. Muskelschwundkrankheiten, dienenCaveolae, the characteristic plasma membrane invaginations present in many cells, have been associated with numerous functions that still remain debated. Taking into account the particular abundance of caveolae in cells experiencing mechanical stress, it was proposed that caveolae constitute a membrane reservoir and bu er the membrane tension upon mechanical stress. The present work aimed to check this proposition experimentally. First, the in uence of caveolae on the membrane tension was studied on mouse lung endothelial cells in resting conditions using tether extraction with optically trapped beads. Second, experiments on cells upon acute mechanical stress showed that caveolae serve as a membrane reservoir bu ering surges in membrane tension in their immediate, ATP- and cytoskeleton-independent attening and disassembly. Third, caveolae incorporated in membrane vesicles also showed the tension bu ering. Finally, in a physiologically more relevant case, human muscle cells were studied, and it was shown that mutations with impaired caveolae which are described in muscular dystrophies render muscle cells less resistant to mechanical stress. In Summary the present work provides experimental evidence for the hypothesis that caveolae bu er the membrane tension upon mechanical stress. The fact that this was observed in cells and membrane vesicles in an ATP and cytoskeleton independent manner reveals a passive, mechanically driven process. This could be a leap forward in the comprehension of the role of caveolae in the cell, and in the understanding of genetic diseases like muscular dystrophies
Cavéoles sont des invaginations caractéristiques de la membrane plas- mique présents dans beaucoup de types cellulaires. Ils sont liées à plusieurs fonctions cellulaires, ce qui sont encore débattues. Prenant compte de l importance des cavéoles dans les cellules soumises au stress mécanique, les cavéoles sont proposées de constituer un réservoir membranaire et de tamponner la tension membranaire pendant des stresses mécaniques. Cette étude a eu le but de tester cette hypothèse expérimentalement. En premier, l in uence des cavéoles sur la tension membranaire au repos a été étudiée sur des cellules endothéliales du poumon de la souris. Puis, on a montré que les cavéoles tamponnent l augmentation de la tension membranaire après l application d un stress mécanique. En suite, la réalisation des vésicules membranaires contenant des cavéoles a permit de montrer leur rôle comme réservoir membranaire dans un système simpli é. Finalement, dans un contexte physiologiquement plus relevant, l étude des cellules musculaires a montrée que les mutations du cavéolin associées aux dystrophies musculaires rendent les cellules moins résistante aux stresses mécaniques. En conclusion, cette étude supporte l\'hypothèse que les cavéoles tamponnent la tension membranaire pendant des stresses mécaniques. Le fait que cela se passe dans les cellules et les vésicules indépendamment d ATP et du cytosquelette révèlent un processus passif et mécanique. Cela pourrait servir à une meilleure compréhension du rôle des cavéoles dans la cellule et les maladies génétiques comme les dystrophies musculaires
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Kottke, Peter Arthur. "Rheological Implications of Tension in Liquids". Diss., Georgia Institute of Technology, 2004. http://hdl.handle.net/1853/5015.
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This research investigates effects of tensile stresses in liquids. Areas of application include bearing lubrication and polymer processing, in which liquids may be subjected to hydrostatic tension or large shear stresses.
A primary thrust of this research is the development of a criterion for liquid failure, or cavitation, based upon the general state of stress in the liquid. A variable pressure, rotating inner cylinder, Couette viscometer has been designed and used to test a hypothesized cavitation criterion. The criterion, that cavitation will occur when a principal normal stress in a liquid becomes more tensile than some critical stress, is supported by the results of experiments with the viscometer for a Newtonian liquid. Based upon experimental observation of cavitation, a model for cavitation inception from crevice stabilized gas nuclei, and gaseous, as opposed to vaporous, cavitation is hypothesized.
The cavitation inception model is investigated through numerical simulation, primarily using the boundary element method. Only Newtonian liquids are modeled, and, for simulation purposes, the model is reduced to two dimensions and the limit of negligible inertia is considered. The model includes contact line dynamics. Mass transport of dissolved gas through the liquid and in or out of the gas nucleus is considered. The numerical simulations provide important information about the probable nature of cavitation nucleation sites as well as conditions for cavitation inception.
The cavitation criterion predicts cavitation in simple shear, which has implications for rheological measurements. It can cause apparent shear thinning and thixotropy. Additionally, there is evidence suggesting a possible link between shear cavitation and extrusion defects such as sharkskin. A variable pressure capillary tube viscometer was designed and constructed to investigate a hypothesized relationship between shear cavitation and extrusion defects. Results indicate that despite the occasional coincidence of occurrence of cavitation and sharkskin defects, cavitation cannot explain the onset of extrusion defects.
If nuclei are removed, then liquids can withstand a negative hydrostatic pressure. A falling body viscometer has been constructed and used to investigate the effect of negative pressures on viscosity. It is found that current pressure viscosity models can be accurately extrapolated to experimentally achievable negative pressures.
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Maraun, Timothy Fritz. "Tension in 18th century Chinese painting". Thesis, University of British Columbia, 1990. http://hdl.handle.net/2429/31841.
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In Western scholarship, eighteenth century Chinese paintings have consistently been seen as playful, eccentric, and odd. This characterization has been based on the formal qualities of some of the paintings. At the same time, Chinese scholars have written of the scholarly virtues and ambitions of the painters producing the works. The contradiction between these two interpretations is in part consistent with the Western and Chinese approaches generally. But it also stems from the mixed signals and information generated in the eighteenth century. The nature of painting, not just formally, but socially has yet to be explained in a way which takes into account some actual historical contradictions of the eighteenth century.
In order to explain these historical tensions, I combine a biographical (Chinese) approach with a contextual approach (Western) in a study of two different scholar painters, Zheng Xie and Li Shan. I juxtapose biographical sources with artworks, and less official writings relating Zheng Xie and Li Shan, in order to describe the tensions involved in painting for the literatus within the merchant culture of Yangzhou.
These tensions existed between the literatus' expected status and that granted him, between his ideal of the role of painting in the scholar's life and the implications of commercial painting, and between his emphasis upon poetry
and his popularity as a painter. In all cases, the tensions in eighteenth century literati painting arise from the difficult relationship between the painter and patron, and between the painter and the ideas of a broader public. The lack of a clear definition of "scholar" and "scholar painting" amongst literati illustrates the literatus' loss of control over the definition of his lifestyle.Arts, Faculty of
Art History, Visual Art and Theory, Department of
Graduate
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Nunez, Ian Louis. "Centrifuge model tension piles in clay". Thesis, University of Cambridge, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.316783.
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Ong, Chee Fatt. "Computer-aided design of tension structures". Thesis, City University London, 1992. http://openaccess.city.ac.uk/7994/.
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This thesis consists of three parts. Part I (chapters 1-4) gives a review and description of the basis for the numerical modelling of tension structures. The discussion in Part I leads to the conclusion of a need for an interactive design procedure for tension structures which is the subject under consideration in Part II (chapters 5-7). In the design of tension structures, an area which requires special attention is the dynamic response often initiated by the action of a natural wind. In Part III (chapters 8 and 9), this area is examined in detail and a strategy is proposed to give an improved modelling of dynamic response. The numerical procedure developed is assessed by comparison with previously reported test results for a pneumatic dome. Chapter 1 gives a general introduction to tension structures, and their main characteristics and behaviour are briefly described. From both the structural and architectural points of view, tension structures (classified as either prestressed cable nets or doubly curved membranes) do offer a number of benefits which arise from their characteristics and behaviour. The different types of cable nets which can be contructed are outlined, and various possible types of membrane structures and membrane materials which can be used are described. In addition, the form-finding and load analysis stages in the design process of tension structures are briefly discussed. An overview of Parts I, II and III of this thesis is also included. As a result of the flexible nature of a tension structure, large deformations often occur under loads acting normal to the surface. In addition, the coated woven fabrics exhibit material non-linearities, ie. the material properties vary under loads. In other words, a full non-linear structural analysis accounting for both material and geometric non-linearities is required in order to give a realistic modelling of the behaviour of a tension structure. Chapter 2 reviews numerical methods which have been widely reported for dealing with nonlinear structural analysis. From the review, it will be noted that the dynamic relaxation (DR) method is well suited to solving the highly non-linear problems which occur particularly in the case of tension structures. The dynamic relaxation method with a finite element idealisation of the structure is chosen as the solution scheme for all the analysis work in this thesis, and a detailed description of the method is given in chapter 3. Features of the method which are particularly useful for the design of tension structures are: (a) the effective decoupling of the equations of compatibility and equilibrium which allows complex material properties modelling and the use of slip cables, etc., and (b) the use of a 'kinetic' damping procedure which permits gross changes in support geometries to be made during interactive form-finding without the possibility of numerical instability. Although the main surface spanning elements may be purely tensile, many tension structures will employ compression and bending elements for their support. For example, as a means of providing support to a large span tension structure, a compression boundary is considered to be an efficient alternative to tension anchorages. In a sense, a compression boundary is complimentary to the tension elements in the structure as these elements also act as supports to the compression boundary. This gives the advantage of a compression boundary comprising of slender sections. The compression boundary is modelled as a series of beam elements. The moment-curvature equations of a beam element expressed in the form of natural stiffness relations, are developed in chapter 4. In addition, the non-linearities, both geometric and material, and boundary conditions which can be dealt with by the beam elements are considered. An outline is given of the implementation of the beam elements using the dynamic relaxation method. Included in chapter 4 are also the results to test problems which have been set up in order to validate the underlying theory and implementation of the beam elements. As tension structures often exhibit complex surface curvatures, a study of surfaces, their properties and behaviour is appropriate, and useful in the understanding of concepts applied in the design process. This study is the subject of chapter 5 which focusses on the relevant topics of differential geometry. A few useful ideas from differential geometry form the basis of certain procedures implemented into the form-finding and patterning stages being considered in chapter 6. The derivation of the equilibrium equations for a surface when acted on by applied loads is also given in chapter 5. The discussion in chapter 6 is about the stages of form-finding and static load analysis in the design process. A review of the available solution methods for the form-finding problem are given in this chapter. In these methods, the solution can be for either the unknown geometry or unknown stresses, or both. The adopted approach in this thesis is to solve for the unknown equilibrium geometry given the stress distributions, and initial and boundary conditions. The controls which can be used during form-finding to achieve the desired geometries of cable nets and membrane structures are discussed. The equilibrium geometry derived from the form-finding stage has to be subsequently evaluated for its performance under loads at the load analysis stage. After an equilibrium geometry which behaves satisfactorily under loads has been achieved, the corresponding cutting patterns are developed in the case of membrane structures. Recent advances in interactive computer graphics technology have made it possible to develop a fully interactive CAD system for tension structures. The development of such a CAD system is the subject of discussion in chapter 7. The CAD system integrates together the form-finding, load analysis and fabrication patterning stages, resulting in a continuous design process. It demonstrates how the various concepts discussed in Part I of this thesis fit together within an interactive environment implemented with an effective and functional user interface. It is illustrated in chapter 7 how such a user interface has been achieved. The CAD system fully exploits the capabilities offered by the available computer hardware such that the computations involved during analysis of the structure, in generation of surface shaded graphic images and so on, can be executed at very high speeds. As a result, the CAD system can respond quickly to the user and is thus consistent with the interactive nature of the design process. The discussion in chapter 7 also provides an insight into the various procedures involved throughout the design process. The CAD system has produced a number of benefits of which the main one is the saving in design time which has been achieved. As the CAD system is highly user friendly, only a short learning period is required, thus enabling it to be used more widely among designers. The CAD system also serves as a useful tool for the communication of ideas between the engineer and the architect. In the design of a tension structure unlike that of a conventional building, there is often close cooperation between the engineer and the architect right from the early stages of conceptual development. In chapter 8, the possible loads which may act on a tension structure during its service life are considered. These loads are applied to the structure at the load analysis stage in the design process. In most cases, the design loads are those due to snow and wind. An accurate assessment of the loads is essential in order to achieve a structurally sound and economic design. In addition, it should be possible to represent the loads in a form which can be easily applied in the structural analysis. The considerations which are involved in the assessments of the snow and wind loads are outlined.
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Ridge, I. M. L. "Bending-tension fatigue of wire rope". Thesis, University of Reading, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.315486.
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Kennedy, Catherine. "Welfare and health : systems in tension". Thesis, University of Glasgow, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.297521.
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Tsai, Frank J. (Frank Jin-Fong) 1976. "Distributed active control for tension structures". Thesis, Massachusetts Institute of Technology, 2000. http://hdl.handle.net/1721.1/81544.
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Mejía, Madrid Renato. "The Tension between work and homelife". IUS ET VERITAS, 2014. http://repositorio.pucp.edu.pe/index/handle/123456789/123440.
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In this paper, the author presents the problem that thetension between work and family life represent. in that way, a gender perspective is used to analyze masculine and feminine roles in different work environments, and compare them with labor policies. the author concludes emphasizing the insufficiency of the actual policies, and then he suggests corresponsibility as a solution.En el presente artículo, el autor presenta el problema de la tensión entre el trabajo y la vida familiar. Para ello, aborda una perspectiva principalmente de género, analizando los roles masculino y femenino en diferentes escenarios laborales, y comparando la situación actual de las políticas laborales impuestas por el estado. Concluye señalando la insuficiencia de las políticas actuales, para luego proponer como solución la corresponsabilidad.
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Pargana, Julio Balsa. "Realistic modelling of tension fabric structures". Thesis, Imperial College London, 2004. http://hdl.handle.net/10044/1/51483.
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An accurate and reliable analysis capability for Tensioned Fabric Structures (TFS) constructed from plain weave PTFE coated glass-fiber fabric has been developed in this work. This analysis facility has in turn enabled an investigation of the behaviour and design of TFS to be conducted. The investigation has revealed deficiencies in current design procedures, which may ultimately result in compromised design, as these are founded on unrealistic overly simplistic design assumptions. The analysis facility developed is based on finite element analysis, and utilizes newly purpose developed elements and a specially developed material model for the fabric component of structures. The new elements and material model for fabric have been integrated into ADAPTIC (Izzuddin, 1991), an advanced nonlinear structural analysis program, allowing real structures to be analysed. The analysis facility developed enables analytical structural models to converge closer to physical reality than allowed by existing analysis facilities, which is attributed to the robust assumptions upon which the new analysis facility is based. As an example of such a robust assumption, fabric patterns are taken to be flat in their unstressed state, a realistic assumption ignored by typical current analysis capabilities for TFS. The accuracy and reliability of the developed finite elements and material model for the fabric are demonstrated to be high, through an appropriate number of verification examples and comparison of experimental test data, for the material response, against the modelled response. Confidence in the analysis facility is thus guaranteed. The work also contains a theoretical deliberation of the current design procedure, the integrated design procedure and a new design procedure called the combined design procedure. The combined design procedure, so called as it is based on both the current design procedure and the integrated design procedure, offers the prospect of considerable improvements to the overall design process for TFS.
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HAMPIKIAN, PASCAL DENIS. "Diode rapide de puissance haute tension". Paris 11, 1991. http://www.theses.fr/1991PA112194.
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Cette these presente l'etude et la realisation de redresseurs rapides haute tension sur silicium du type pin. Ces diodes fonctionnent sous controle d'injection. La charge electrique presente dans la zone centrale pendant la phase de conduction est limitee par la structure des emetteurs n et p. Ce mode de fonctionnement n'est assure qu'avec des emetteurs dont la dose des proches de 2. E+12 cm##2. Cela necessite alors de travailler avec des jonctions courtes inferieures a 400 nm pour garantir a la fois cette dose faible et une concentration en surface indispensable a une bonne prise de contact. Pour eviter une chute en direct trop importante, due a la faible quantite de porteurs injectes, la zone centrale doit avoir une duree de vie elevee et une epaisseur minimum. Pour une tension de claquage de 1000 v et a partir d'un substrat de 40-50 ohm. Cm, le composant est fabrique sur un voile mince de silicium de 0,1 mm, obtenu grace a un assemblage de deux technologies: autosoudage et gravure anisotropique du silicium. Pour une diode de 10 mm#2 ayant une tension de claquage de 1000 v, la chute en direct est de 1,25 v a 20 a. Le temps de recouvrement, pour 20 a commute est de 150 ns. Cette diode n'ayant pas besoin de diffusion metallique, la temperature a moins d'influence sur les performances electriques
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Lindqvist, Sanne. "The Contrastive Tension Methodand Corpus Variety". Thesis, Uppsala universitet, Institutionen för informationsteknologi, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-452234.
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A new method called contrastive tension for creating semantic sentencerepresentations has recently been developed. The method has previously been testedwith three different text collections as source material. This report will continue thiswork and evaluate the method on different kinds of texts. Six text collections will beused. The first four collections contain sentences from four different categories. Thetwo remaining collections are based on the complete works of William Shakespeare.The difference between the two Shakespeare collections is that they use a differentway of dividing the raw text into sentences. The goal of this thesis is to investigate three main points. Firstly, how is the performance on the benchmarks affected by using contrastive tension with different texts? Secondly, does using a text collection that is similar to one of the benchmarking subcategories improve the results on that subcategory? For instance,does a corpus of news headlines result in a higher score on the headline subcategory? Thirdly, is there a difference in performance between the two Shakespeare collections? Can this say anything about the impact of sentence length on performance? The two collections that achieved the highest correlation scores overall were the image caption corpus and, surprisingly, one of the Shakespeare collections. The correlation score is a measure of how well the meaning of sentences are represented by the sentence embeddings, which will be further described in section 2.5. Using acollection similar to a subcategory did improve the score on that subcategorysometimes, but not always. Some collections achieved higher scores than expected on seemingly unrelated subcategories. To conclude, the findings are that the text used as source material does impact the evaluation scores, but not always in the ways that one would expect. The length of the sentences in a corpus appears to have an impact, as the results on the two Shakespeare collections suggest. However, further study is needed to be able to draw definitive conclusions about the importance of sentence length.
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Kim, Jae Seung. "Complex modulus from indirect tension testing". [Gainesville, Fla.] : University of Florida, 2002. http://purl.fcla.edu/fcla/etd/UFE1000133.
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Thesis (M.E.)--University of Florida, 2002.Title from title page of source document. Document formatted into pages; contains x, 96 p.; also contains graphics. Includes vita. Includes bibliographical references.
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Newton, Audrey. "Spaces of Tension and Material Disruptions". Thesis, The University of Sydney, 2018. https://hdl.handle.net/2123/22358.
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Spaces of Tension and Material Disruptions is a project that examines how material and space provoke the vibrancy of a sculpture or sculptural assemblage that is a part of an art installation. To explain vibrancy, I am referring to vibrancy defined by Jane Bennett in her 2010 text, Vibrant Matter, A Political Ecology of Things. She refers to matter’s vibrancy as the furtive energy or force of things within an assemblage’s agency. Using this reference of vibrancy, Spaces of Tension and Material Disruptions suggests that physical space in places and sites can add or detract to a spectator’s experience of witnessing a sculptures vibrancy. This paper questions theatrical methodologies of excess used in the history of Installation Art and reflects on the sculptural, expanded spatiality and phenomenological discourse and practices explored by North American Minimalist, Post Minimalist and Land Artists. Spaces of Tension and Material Disruptions argues that this prominent era of art inadvertently touched on this idea of sculptural vibrancy and in doing so, paved the way for contemporary sculptors to approach space and object so that it creates a unified relationship between the artist, artwork and audience.
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Tones, Matthew. "Nietzsche, Tension and the Tragic Disposition". Thesis, Griffith University, 2013. http://hdl.handle.net/10072/365917.
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This thesis examines the role that tension plays in Nietzsche’s recovery of the tragic disposition. This is achieved by examining the ontological structure to the tragic disposition that is present in Nietzsche’s earliest work on the Greeks and then exploring its presence in points of tension found in Nietzsche’s more mature concern with nobility. In pursuing this ontological foundation, the work builds upon recent trends in Nietzsche scholarship that have established the centrality of a naturalist argument derived from the influence of the pre-Platonic Greeks. It is the ontological aspect of the tragic disposition identified in Nietzsche’s earliest interpretations of Greek phusis and the inherent tensions of the chthonic present in this hylemorphic foundation that are examined to demonstrate the importance of the notion of tension to Nietzsche’s recovery of a tragic disposition. By bringing to light the functional importance of tension for the Greeks in the ontological, largely exhumed from his earliest work, varying points of tension can be identified that demonstrate a re-emergence at different aspects in his later work. By examining the role of these aspects, the evolving influence of tension is shown to play a central role in the re-emergence of the noble that possesses the tragic disposition.Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Humanities
Arts, Education and Law
Full Text
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Napier, Amelia Carroll. "Generational Tension in Middle English Lais". W&M ScholarWorks, 1992. https://scholarworks.wm.edu/etd/1539625740.
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Omair, Moayad R. "The behaviour of welded T-end plate connections to rectangular hollow section (RHS)". Thesis, Coventry University, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.313163.
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Jihad, Hamza El. "Contribution à l'étude des convertisseurs multi-niveaux moyenne tension : réduction d'harmoniques BF et linéarisation de leur tension". Electronic Thesis or Diss., Université de Lorraine, 2019. http://www.theses.fr/2019LORR0175.
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Cette thèse traite des convertisseurs de puissance multi-niveaux destinés aux applications d’entraînements électriques, utilisés notamment dans le domaine de l’Oil & Gas et de la propulsion marine, ou bien aux applications réseaux comme la compensation de l’énergie réactive. L’objectif est l’optimisation des commandes de ces convertisseurs de façon à réduire le contenu harmonique de la tension de sortie et donc du courant, paramètre très important pour le dimensionnement à la fois des filtres de sortie et des machines électriques qui y sont connectées. Dans la première partie de ce mémoire, les différentes topologies multi-niveaux sont analysées et trois topologies cinq niveaux retenues sont comparées en termes de nombre de composants semi-conducteurs, des pertes, du contenu harmonique et de l’énergie stockée dans les éléments passifs. Selon le type de l’application, l’une d’entre elles est préférée aux autres. En deuxième partie, nous avons proposé une méthode de réduction d’harmoniques basse fréquence qui consiste à maîtriser la phase des porteuses MLI pour des ratios entiers des fréquences de découpage et du fondamentale de la tension de référence. La minimisation des harmoniques basse fréquence de la tension de sortie du convertisseur par l’optimisation de la phase des porteuses est validée d’abord par des simulations numériques puis implémentée pratiquement et validée à l’aide d’un simulateur temps réel RT-Lab. Pour pallier aux problèmes de non-linéarités introduites par les méthodes classiques de ”clamping” des tensions de références des convertisseurs multi-niveaux, limitant l’amplitude de la tension de sortie maximale atteignable, nous proposons une nouvelle méthode de linéarisation en dernière partie de ce mémoire. Il s’agit d’ajouter une composante homopolaire optimisée aux tensions de références des convertisseurs multi-niveaux pour linéariser le fondamental de leurs tensions de sortie, ce qui permet d’accroître le maximum de leur amplitude. Cette méthode est testée par simulation numérique dans la commande d’un système d’entraînement électrique complet lui permettant de fonctionner sur toute la plage de vitesse, sans affecter l’équilibrage des tensions des capacités du bus continu principalThis thesis deals with multi-level power converters for electrical drive applications, used in particular in the field of Oil & Gas and marine propulsion, or for network applications such as reactive energy compensation. The objective is to optimize the controls of these converters in order to reduce the harmonic content of the output voltage and therefore of the current, a very important parameter for the sizing of both the output filters and the electrical machines connected to them. In the first part of this thesis, the different multi-level topologies are analyzed and three selected five-level topologies are compared in terms of the number of semiconductor components, losses, harmonic content and the energy stored in the passive elements. Depending on the application type, one of them is preferred over the others. In the second part, we proposed a method for reducing low frequency harmonics of the multilevel converter output voltage, which consists in controlling the phase of the PWM carriers for integer ratios of the switching frequency and the fundamental frequency. The minimization of low-frequency harmonics of the converter output voltage by optimizing the carrier phase is first validated by numerical simulations and then practically implemented and validated using a real time simulator RT-Lab. To overcome the problems of non-linearities introduced by the classical clamping methods of the reference voltages of multi-level converters, limiting the amplitude of the maximum achievable output voltage, we propose a new linearization method in the last part of this thesis. This involves adding an optimized zero-sequence component to the reference voltages of multi-level converters to linearize the fundamental of their output voltages, which makes it possible to increase their amplitude to its maximum achievable value. This method is tested by numerical simulation in the control of a complete electric drive system allowing it to operate over the entire speed range, without affecting the voltage balancing of the main DC bus capacitors
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MENDES, ROBERTA RODRIGUES. "EXPERIMENTAL STUDY OF CONCRETE SPECIMENS REINFORCED WITH STEEL FIBERS SUBJECT TO TENSION UNDER DIAMETRAL COMPRESSION AND DIRECT TENSION". PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2016. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=29303@1.
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PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIROCOORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIOR
PROGRAMA DE EXCELENCIA ACADEMICA
Esta pesquisa apresenta um estudo experimental do comportamento de corpos de prova de concreto armado com fibras metálicas comprimidos diametralmente e os submetidos à tração direta. Foram analisados 72 corpos de prova no LEM-DEC da PUC-Rio, sendo 54 cilíndricos variando-se o diâmetro e o consumo de fibras para o ensaio de compressão diametral e 18 variando-se o consumo de fibras para o ensaio de tração direta. Os 54 corpos de prova foram divididos em três grupos de acordo com a resistência à compressão (20, 30 e 50 MPa), cada grupo com 18 corpos de prova com consumo de fibras (20 kg/metro cúbico, 40 kg/metro cúbico e 60 kg/metro cúbico) e diâmetros distintos (5 cm, 10 cm e 15 cm). Foram avaliados a resistência de tração, energia de deformação e efeito escala. Os resultados obtidos permitem analisar a influência do consumo de fibras e do diâmetro do corpo de prova. A resistência à tração varia linearmente com o consumo e o diâmetro do corpo de prova, verificando-se que a resistência do corpo de prova com diâmetro de 15 cm é 42 por cento menor que o de 5 cm. A energia de deformação não apresentou acréscimo significativo com o aumento do consumo de fibras de 40 kg/metro cúbico para 60 kg/metro cúbico. A análise do efeito escala mostra um decréscimo da resistência à tração com incremento da dimensão do corpo de prova, e os resultados se assemelham aos estudos realizados por Carpinteri (1995), mesmo com consumos de fibras distintos. Os 18 corpos de prova submetidos à tração direta têm a mesma dimensão, diferindo em resistência (20, 30 e 50 MPa) e consumo (20 kg/metro cúbico, 40 kg/metro cúbico e 60 kg/metro cúbico). Nesses foi avaliada a energia de deformação plástica e elástica. A região plástica não fica delineada para o consumo de 20 kg/metro cúbico apresentando um comportamento similar ao concreto convencional.
This research presents an experimental study on the behavior of reinforced concrete specimens with steel fibers submitted to the splitting test and to direct tension. A total of 72 specimens were tested in the LEM-DEC PUC-Rio; 54 specimens with three different diameters and fiber consume for the diametral compression test and 18 with variations of fiber volume fraction for the direct tension test. The 54 specimens were divided into three groups according to their compressive strength (20, 30 and 50 MPa), each group having 18 specimens with variations of fiber volume fraction (20 kg / cubic meter, 40 kg / cubic meter and 60 kg / cubic meter and diameter (5 cm, 10 cm and 15 cm). The purpose was to investigate the tensile stress, the fracture energy and the size effect. The results allowed the analysis of the influence of the fibers and specimen diameter on each variable before mentioned. The tensile stress varies linearly with fiber volume fraction and diameter, and the resistance of the specimens with 15 cm in diameter is 42 per cent less than the resistance of the 5 cm specimen. The fracture energy was not increased significantly with the increase of fiber content from 40 kg fibers / cubic meter to 60 kg / cubic meter. The size effect analysis shows that tensile strength decreases as the diameter increases. These results are similar to those of studies conducted by Carpinteri (1995), even with different values of fiber consume. The 18 specimens submitted to direct tension had the same diameter, varying in resistance (20, 30 and 50 MPa) and fiber volume fraction (20 kg / cubic meter, 40 kg / cubic meter and 60 kg /cubic meter). Here the plastic and elastic deformations were evaluated. The plastic region is not clearly defined for the fiber fraction of 20 kg / cubic meter presenting a behavior similar to the conventional concrete.
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Bassin, Cédric. "Dispositifs haute-tension pour technologies CMOS standard /". [S.l.] : [s.n.], 2001. http://library.epfl.ch/theses/?nr=2447.
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Touhami, Youssef. "Effects of viscosity on dynamic interfacial tension". Thesis, University of Ottawa (Canada), 1990. http://hdl.handle.net/10393/5607.
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In this study, we have investigated the interfacial tension (IFT)-lowering potential of a range of caustic solutions which were contacted with dilute solution of linoleic acid in light paraffin oil. Two polymers, namely, polyvinyl alcohol and polyacrylamide were added to the caustic solution in order to increase bulk phase viscosity. The dynamic IFT of caustic, polymer and caustic-polymer solutions were measured. By using different linoleic acid concentrations up to 100 mM, it was found that an increase in acid concentration was accompanied by a decrease in IFT for any given caustic composition. When the acid strength was fixed at 10 mM and the caustic concentration was also increased up maximum of 250 mM, the lowest IFT values were obtained at 12.5 mM NaOH. The dilute polymer solutions lowered the IFT of the oleic phase against neutral water from 30.0 to about 15 mN/m. However, the addition of the polymeric material to the caustic solution produced a marginal reduction in dynamic IFT at early contact times and also produced characteristic IFT minima at all caustic concentrations. (Abstract shortened by UMI.)
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Bailey, Bruce Burgess, i Bruce Burgess Bailey. "Disc size influence on tension infiltrometer performance". Thesis, The University of Arizona, 1995. http://hdl.handle.net/10150/626923.
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A series of tension infiltration measurements have been made to derive saturated
hydraulic conductivities and alpha (a) soil parameter values of a heterogeneous desert
soil. Four diameter sizes, 8. 7, 20, 28.2, and 40 cm, were used, yielding saturated
hydraulic conductivity values of 0.05, 0.09. 0.10, and 0.11 cm/min, respectively. These
increasing mean hydraulic conductivity values with increased disc size are the result of
improved sampling of the heterogeneous soil. Standard deviation values are 0.04, 0.03,
0.02, and 0.01, respectively. Respective a mean values for increasing disc size are 0.15,
0.13, 0.11, and 0.10, with respective standard deviations of 0.04, 0.03, 0.03, and 0.02.
The decreasing trends of both standard deviations with increasing disc size is attributed
to sampling larger areas and reducing edge effects. These results imply that for
heterogeneous soils, larger diameter discs have an advantage over the standard 8. 7 and
20 cm disc diameters currently being used.
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Jensen, Ward Calvin. "A capillary method for line tension determination". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp05/mq22607.pdf.
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Sokolov, Aleksandr. "Tension stiffening model for reinforced concrete beams". Doctoral thesis, Lithuanian Academic Libraries Network (LABT), 2010. http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2010~D_20100803_110628-45999.
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Modelling behaviour of cracked tensile concrete is a complicated issue. Due to bond with reinforcement, the cracked concrete between cracks carries a certain amount of tensile force normal to the cracked plane. Concrete adheres to rein-forcement bars and contributes to overall stiffness of the structure. The phe-nomenon, called tension-stiffening, has significant influence on the results of short-term deformational analysis. Assumption of a tension-stiffening law has great influence on numerical results of load – deflection behaviour of reinforced concrete members subjected to short – term loading. Under wrong assumption of this law, errors in calculated deflections, particularly for lightly members, may exceed 100 %. Most known tension-stiffening relationships relate average stresses to average strains. However, some experimental and theoretical investi-gations have shown that tension-stiffening may be affected by other parameters. The scientific supervisor of the thesis has proposed a tension-stiffening model depending on reinforcement ratio. This model has been developed using experi-mental data reported in the literature. Besides, concrete shrinkage effect was not taken into account. The main objective of this PhD dissertation is to propose a tension-stiffening law for bending RC members subjected to short-term loading with eliminated concrete shrinkage effect.Gelžbetonis yra kompozitinė medžiaga, kurios komponentai yra betonas ir plieninė armatūra. Kaip žinoma, betono stipris tempiant yra 10-20 kartų mažesnis nei stipris gniuždant. Atrodytų, kad tempiamojo betono įtaka, atlaikant įrąžas skerspjūvyje, yra nereikšminga. Iš tiesų, nustatant lenkiamųjų elementų stiprumą normaliniame pjūvyje, tempiamo betono įtempių galima nevertinti. Kita vertus, skaičiuojant įlinkius, neįvertinus tempiamojo betono įtakos, gali būti daroma didesnė nei 100 % paklaida. Adekvatus supleišėjusio tempiamojo betono įtakos įvertinimas, nustatant trumpalaike apkrova veikiamų gelžbetoninių elementų deformacijas, yra bene svarbiausia ir sudėtingiausia problema. Plyšio vietoje betonas negali atlaikyti tempimo įtempių, todėl visą įrąžą atlaiko armatūra. Kadangi plyšyje ir gretimuose pjūviuose armatūra praslysta betono atžvilgiu, kontakto zonoje atsiranda tangentiniai įtempiai. Šie įtempiai perduodami betonui, todėl jis atlaiko tempimo įtempius. Armatūros ir betono sąveika ruožuose tarp plyšių standina gelžbetoninį elementą. Supleišėjusio betono gebėjimas atlaikyti tempimo įtempius vadinama tempimo sustandėjimu (angl. tension stiffening). Šis efektas dažniausiai modeliuojamas supleišėjusio betono įtempių ir deformacijų diagrama, taikant vidutinių plyšių koncepciją. Tuomet neatsižvelgiama į diskrečius plyšius, o supleišėjęs betonas traktuojamas kaip ortotropinė medžiaga su pakitusiomis savybėmis. Dauguma tempimo sustandėjimo modelių įvertina betono įtempių... [toliau žr. visą tekstą]
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Grimshaw, Matthew John. "Effects of oxygen tension on articular chondrocytes". Thesis, Imperial College London, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.313728.
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Clewett, James. "Emergent surface tension in boiling granular media". Thesis, University of Nottingham, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.604898.
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In this thesis we present findings from an experimental and numerical study of loosely confined, dry granular gases subject to vertical vibration. We found that the system phase separates into a high-density, liquid-like phase and a low-density gas-like phase. The phase separation was shown to occur at a critical driving amplitude but is independent of frequency. To introduce our work, we give an overview of phase separation in driven granular gases. Ofpatiicular interest are: a solid-liquid-like phase separation in tightly confined, dry granular mono layers and a liquid-gas-like phase separation in loosely confined, wet granular gases. Our system differs from the above examples in two significant ways: our cell is deeper than that used to tightly confine the granular mono layers, so that we avoid the formation of a solid-like phase; our patiicles are dry and as such there are no cohesive forces between the particles. The liquid-gas phase separation is a useful system in which to study far-from-equilibrium phenomena because the particles are easily homogenised and then quenched into the phase-separating state. The system also allows us to smoothly approach the phase-transition boundaries. The phase separation was shown to be spinodal driven, with a region of negative compressibility due to an excess in the granular temperature of the particles in the dilute phase. The origin of the excess temperature was traced to the coherent motion of particles above a critical driving amplitude. By switching to a frequency modulated driving signal the phase separation was suppressed, demonstrating the requirement for coherent motion. The experiment shows the importance of using realistic driving motion in simulations. The phase-separation coarsening dynamics were shown to be similar to that of thermodynamic systems evolving under curvature driven diffusion (model B). Using the Cahn-Hilliard equation we accurately predict the dominant length scale in the early-time dynamics. In thelIDodynamics the Cahn-Hilliard equation desclibes the minimisation of an excess interfacial energy. This suggests that we might define an effective free energy for our granular system, however, as yet it is not clear what is meant by free energy in the context of a far-fi·om-equilibrium system. Finally, by studying the surface tension of quasi-2D liquid-like droplets in the steady state, we found behaviour consistent with Laplace's equation, demonstrating that the surface tension is real. Detailed measurements of the pressure in the interfacial region show that the surface tension results predominantly from an unexpected anisotropy in the kinetic energy part of the pressure tensor, in contrast to thelIDodynamic systems where surface tension arises from either the attractive interaction between pmticles or entropit considerations. The general nature of our argument for the Oligin of the surface tension means that it should apply to other granular phase separations and segregations in granular rnixhlres. As such this might be a new general mechanism in far-from-equiliblium thermodynamics. Throughout the thesis we use numerical simulations, configured with a geometry matching that of the experimental cell. To simulate the two million particles required we created a bespoke molecular dynamics code to execute using GPGPU hardware. The peliormance of our simulations was comparable to the state of the art in the literature, approximately twenty times faster than simulations on modern CPU processors.
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Li, Yuen-mei Emmy, i 李琬微. "Cost-effectiveness of treating normal tension glaucoma". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2010. http://hub.hku.hk/bib/B45173114.
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Pate, Chad P. "Easing the Arctic tension an economic solution". Thesis, Monterey, California. Naval Postgraduate School, 2010. http://hdl.handle.net/10945/5089.
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Approved for public release; distribution is unlimitedClimate change in the Arctic is affecting the ice melt more rapidly than previously anticipated and the Arctic is now forecast to be ice-free by 2013. International borders, fossil fuel reservoirs and new sea routes for navigation are just a few of the issues at stake due to the receding ice cover. Contrary to those who perceive U.S.-Russian conflict arising out of the region and advocate a military response, this thesis argues that the Arctic, precisely because of its rich hydrocarbon resources, may prove to be amenable to a capitalist peace. Research suggests that nations linked by economic interdependence are less apt to engage in conflict with each other. Nations seeking foreign direct investment will be less likely to initiate conflict, as this would diminish the potential for attracting foreign capital. Russia's economy is dependent on oil and natural gas exports and these industries have created enormous wealth for the nation. Yet Russia's existing fossil fuel reservoirs are nearing exhaustion. Tapping into Arctic reserves is a strategic imperative for Russia, however, it lacks the technological capacity to do so. The energy industry in the West is farther along in developing such extractive technology. This thesis argues that Russia's need of foreign assistance in its hydrocarbon sector will make Russia more pacific, thereby offsetting realist fears of a military conflict in the Arctic.
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Dandekar, Abhijit Yeshwant. "Interfacial tension and viscosity of reservoir fluids". Thesis, Heriot-Watt University, 1994. http://hdl.handle.net/10399/1397.
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Drabble, Michael J. "Turbulent wind action on tension leg platforms". Thesis, Heriot-Watt University, 1989. http://hdl.handle.net/10399/855.
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Scott, R. H. "Tension stiffening effects in reinforced concrete members". Thesis, Durham University, 1985. http://etheses.dur.ac.uk/6803/.
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This thesis is in two parts which are related by the common theme of tension stiffening. Part I develops the concept of a stress-strain envelope to model the behaviour of the concrete in tension below the neutral axis of a reinforced concrete beam. This is substantiated by an analysis of the data from fourteen test beams. The envelope concept is then applied to the calculation of the moment-curvature relationships for these beams, which are also compared with the test results .Part II presents an experimental investigation of the longitudinal reinforcement strain distributions in reinforced concrete tension members. Test results for fourteen specimens having various cross-sections and reinforcement types are presented, with the reinforcement strains being measured by strain gauging the reinforcement internally. The comprehensive analysis of the test results includes specific design recommendations concerning bond stresses at working loads. Suggestions are made for further work.