Дисертації: "Nox scaling"

1

Hussain, Mazhur. "Laser diagnosis of gas turbine fuel sprays : scaling effects on NOx emissions and stability." Thesis, Cranfield University, 2009. http://dspace.lib.cranfield.ac.uk/handle/1826/8291.

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This thesis first provided strategic recommendations for the research sponsor, Rolls- Royce plc (RR) and then applied optical diagnostics to measure aero gas turbine fuel spray properties in order to predict Oxides of Nitrogen (NOx) emissions and combustion instability. Analysis of the large civil aero engine sector suggested possible courses of action for RR to protect itself from short-term market volatilities and also prepare for three long term changes in strategic operating context: air traffic growth; tighter United Nations enforced aero engine combustion emissions legislation and entry of civil aviation into the European Union Emissions Trading Scheme. A collaborative game theoretic approach was explored during the pre-competitive, pre-technology, capability acquisition aero engine design phase on unproven future technologies to reduce R&D expenditures, development times and the costs of failure. Lean Prevapourised Premixed combustion demands excellent spray atomisation quality to sustain combustion efficiency, stability and to minimise pollutants. Post development of an improved procedure to calibrate laser signals, methodology to predict NOx and technique to optimise rig operating conditions that minimised fractional discrepancies in two-phase flow behaviour with corresponding engine conditions, this thesis applied quantitative Planar Laser Induced Fluorescence (PLIF) and Laser Sheet Dropsizing (LSD) to measure the fuel placement and dropsize distribution in the near nozzle regions of RR liquid-fuelled hybrid, airblast and pressure-swirl sprays. Measurements were made under non-combusting, low pressure conditions and results were processed to identify fuel injector designs that exhibited low emissions and high stability for the Affordable Near Term Low Emissions (ANTLE) and Instability Control of Low Emission Aero-Engine Combustors (ICLEAC) engine demonstrator programmes. Results also provided validation data and boundary conditions for spray computational codes. Research findings will improve RR core competencies in fuel injection research to accelerate the development and deployment of low emissions aero engine technology.

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2

Lübeck, Sven. "Universal scaling behavior of non-equilibrium phase transitions." [S.l. : s.n.], 2004. http://deposit.ddb.de/cgi-bin/dokserv?idn=973492562.

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3

Bell, S. C. "Scaling theory of non-linear and incommensurate systems." Thesis, University of Oxford, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.376893.

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4

Sbeih, Reema. "NON-LINEAR MAPS BETWEEN SUBSETS OF BANACH SPACES." Kent State University / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=kent1251217291.

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5

Gray, Jonathan David. "Non-Newtonian scaling of blood flow in a femoral bypass." Thesis, University of Liverpool, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.399059.

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6

Garland, James Matthew. "Beam dynamics studies of the EMMA linear non-scaling FFAG." Thesis, University of Manchester, 2014. https://www.research.manchester.ac.uk/portal/en/theses/beam-dynamics-studies-of-the-emma-linear-nonscaling-ffag(5b375a2d-0636-422d-a0d6-2cc941ebd01f).html.

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The development of charged particle accelerators is today reaching far beyond the realm of fundamental particle physics research. Many non-trivial social and political problems may find part of their solution lies in accelerator physics. For example, with fossil fuels becoming ever more controversial and expensive to obtain, the use of Accelerator Driven Sub-critical Reactors (ADSR) powered by rapid cycling, high current proton accelerators and thorium fuel could become part of the energy solution. Through the simplicity of the Bragg peak, cancer therapy could be enhanced through the use of high repetition rate, variable energy proton accelerators small enough to use in treatment centres. The growing problem of long lived nuclear waste storage could become a moot point through the use of high current, high power proton accelerators coupled with neutron spallation. These rapidly growing areas of study are fuelled by the development of the Fixed-Field Alternating-Gradient (FFAG) accelerator, and more recently the non-scaling FFAG. The FFAG has the ability to accelerate high current, low quality bunches of particles in very short time scales due to the fixed-field nature of its magnets. This rapid acceleration can be of the order 500 nanoseconds to 1 microsecond meaning a fast cycling rate of the machine is possible. This allows the realistic development of the ADSR, proton therapy machine and even the muon accelerator. The Electron Model with Many Applications (EMMA) accelerator is the world's first linear non-scaling FFAG and is an electron proof-of-principle accelerator based at Daresbury Laboratory, UK. EMMA can accelerate over its energy range of 10 - 20 MeV in approximately 5 - 10 machine revolutions (~275 - 500 nanoseconds) using fixed-frequency novel acceleration techniques. The accelerator contains fixed-field, constant gradient quadrupole magnets which provide all the bending and focussing to the particles. Due to the linear non-scaling nature of EMMA, many transverse integer tune values are crossed which typically cause resonant effects resulting in bunch degradation and loss. It was proposed and demonstrated that rapid crossing (in 5 - 10 turns) of integer tune values in EMMA did not result in transverse amplitude growth and particle loss. If the wider societal goals of the non-scaling FFAG are to be realised, protons and other heavy ions must be accelerated. Current technological limitations dictate that longer acceleration times of the order 1000's of turns would be necessary in proton machines of similar design to EMMA. Hence slower integer tune crossing was studied using acceleration in a synchrotron bucket in EMMA. It was found experimentally that below the nominal EMMA operating acceleration rate of 2.0 MV per turn, instabilities begin to manifest. This was indicated in the growth of closed orbit distortion (COD) and through simulation it was found that betatron amplitude growth coupled with COD resulted in eventual loss of particles to the physical aperture when crossing integer tunes. Through simulation, the amplitude growth of particles crossing integer tunes in the EMMA non-scaling FFAG was found to agree with a theory of resonance crossing proposed by R. Baartman. This theory shows that amplitude growth is proportional to $1/\sqrt(Q')$ where $Q'$ is the tune crossing rate of the particles. This means that the slower the acceleration, the slower an integer tune is crossed and hence more amplitude is gained. It was also shown that strength of the magnetic errors driving the resonant conditions was proportional to the amplitude growth.

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7

Sublette, Michelle A. "USABILITY IS NOT JUST USABILITY: DISCOVERING THE STRATEGIES USED BY NON-EXPERTS IN MAKING USABILITY PREDICTIONS." UKnowledge, 2017. http://uknowledge.uky.edu/psychology_etds/114.

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Much of the research on metacognition in human factors has focused on prescriptive, normative strategy training. That is, many researchers have concentrated their efforts on finding ways to improve system users’ prediction, planning, monitoring and evaluation strategies for tasks. However little research has focused on the strategies and heuristics users employ on their own to make usability predictions. Understanding usability prediction methods is critical because users’ predictions inform their expectations about whether they will make errors using a product, how much effort they will need to expend to be successful in using the product, whether they can perform two tasks successfully at the same time, whether the costs of learning to use a device are worth the benefits of using it, which tools will assist in accomplishing goals and which tools will make performing the same task more difficult. The following study aims to identify the specific strategies people use to make usability predictions about product designs. From these strategies a set of guidelines, for designers who wish to ensure users’ expectations meet post hoc usability assessments, were proposed. The study was completed in two phases. During the first phase of this study, prediction strategies were elicited by 1) asking participants to make routine product usability judgments, from which implicit strategies can be inferred, and by 2) using explicit free-response methods. Judgments were analyzed using multi-dimensional scaling (MDS) methods to establish the number of dimensions that are implicitly used to predict usability. Subject matter experts (SMEs) coded free-response strategies using coding schemes developed in a pilot study. SMEs will also matched user strategies to formal, professional usability standards. The outcome of Phase 1 was usability taxonomy for classifying usability strategies that includes both expert and user language. The procedure was repeated with three different product design classes to determine how strategies differ as a function of the to-be-judged product. During the second phase of the study, a new group of participants rated specific usability attributes of designs to validate the strategies collected from users’ free-responses in Phase 1. Attributes were selected based on the strategies discovered in Phase 1. These usability attribute ratings helped to inform interpretations of the dimensions of the MDS model generated in Phase 1 and provided input into defining the usability attributes that influenced usability predictions. Results of this study reveal that the type design class participants evaluated had a significant effect on the type of strategy participants used to make their a priori usability assessments (UAs). Participants reported using “complexity” or “organization” most often to predict the usability of cookbooks. Participants reported using “mental simulation” or “typicality/familiarity” most often for predicting the usability of drinking glasses. Participants reported using “complexity,” “organization,” and to a lesser extent “typicality/familiarity,” and “mental simulation” as strategies for predicting the usability of cooktops. MDS methods were used to uncover the underlying dimension of the UA space. For drinking glasses, the “fanciness” and “holdability” were associated with UAs. For cooktops, “the number of controls” and whether participants believed “it was easy to understand how each burner was controlled” were associated with making UAs. And for cookbooks, “the length of the instructions” and “poor contrast of the text with the background” were associated with UAs. Overall, there is evidence that at least some participants in Phase 2 used terminology that was consistent with the terminology people used to describe the designs during Phase 1 and that these were congruent with the uncovered strategies.

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8

Fritsch, Peter. "Non-Equilibrium Scaling Analysis of Quantum Dots in the Kondo Regime." Diss., lmu, 2009. http://nbn-resolving.de/urn:nbn:de:bvb:19-102277.

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9

Chan, Chun Keung. "A study on non-volatile memory scaling in the sub-100nm regime /." View abstract or full-text, 2005. http://library.ust.hk/cgi/db/thesis.pl?ELEC%202005%20CHAN.

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10

Thompson, Carla L. "Scaling the Zachman Framework a software development methodology for non-enterprise applications /." [Denver, Colo.] : Regis University, 2006. http://165.236.235.140/lib/CThompson2006.pdf.

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11

Alotaibi, Khaled. "Non-metric multi-dimensional scaling for distance-based privacy-preserving data mining." Thesis, University of East Anglia, 2014. https://ueaeprints.uea.ac.uk/52228/.

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Recent advances in the field of data mining have led to major concerns about privacy. Sharing data with external parties for analysis puts private information at risk. The original data are often perturbed before external release to protect private information. However, data perturbation can decrease the utility of the output. A good perturbation technique requires balance between privacy and utility. This study proposes a new method for data perturbation in the context of distance-based data mining. We propose the use of non-metric multi-dimensional scaling (MDS) as a suitable technique to perturb data that are intended for distance-based data mining. The basic premise of this approach is to transform the original data into a lower dimensional space and generate new data that protect private details while maintaining good utility for distance-based data mining analysis. We investigate the extent the perturbed data are able to preserve useful statistics for distance-based analysis and to provide protection against malicious attacks. We demonstrate that our method provides an adequate alternative to data randomisation approaches and other dimensionality reduction approaches. Testing is conducted on a wide range of benchmarked datasets and against some existing perturbation methods. The results confirm that our method has very good overall performance, is competitive with other techniques, and produces clustering and classification results at least as good, and in some cases better, than the results obtained from the original data.

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12

Perniola, Luca Vito Bruno. "Modeling, electrical characterization and scaling issues of discrete-trap non-volatile memories." Grenoble INPG, 2005. http://www.theses.fr/2005INPG0085.

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La thèse de doctorat, effectuée en cotutelle entre l'Institut National Polytechnique de Grenoble et l'Université de Pise, a eu pour objectif la caractérisation et la modélisation des mémoires non-volatile à sites de piégeage discrets à base de nanocristaux ou de type SONOS ou NROM. On a pu développer une analyse commune du comportement électrique pour ces différentes architectures, en particulier en ce qui concerne la distribution statistique de la fenêtre de programmation, du fonctionnement à deux bits ("dual-bit ") et de la rétention des données sous différentes conditions expérimentales (chargement initial ou température). Le contenu de la thèse comporte une partie expérimentale relatant les résultats de la caractérisation électrique des mémoires étudiées et une partie théorique constituée par les résultats des simulations analytique et numérique développées pour les prévisions de la miniaturisation de ce type des mémoires
The PhD thesis, made in collaboration between the Institut National Polytechnique de Grenoble and the University of Pisa, had the final objective to characterise and model the special effects of discrete-trap non-volatile memories as nanocrystal, SONOS or NROM memories. We could develop a common analysis of some electrical features of these different architectures, like the programming window distribution, the "dual-bit" behavior and the data retention under different experimental conditions (initial write or test's temperature). The content of the PhD thesis is made of a part constituted by experimental results of electrical characterization of memories is presented, and another part constituted by the modelling results from analytical and numerical simulations, developed for the investigation of the scaling issues related to these types of memories

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13

Farruggia, Frank Thomas. "A FLORISTIC DESCRIPTION OF A NEOTROPICAL COASTAL SAVANNA IN BELIZE." Miami University / OhioLINK, 2004. http://rave.ohiolink.edu/etdc/view?acc_num=miami1090942598.

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14

McGrory, Sarah. "Non-parametric item response theory applications in the assessment of dementia." Thesis, University of Edinburgh, 2015. http://hdl.handle.net/1842/16173.

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This thesis sought to address the application of non-parametric item response theory (NIRT) to cognitive and functional assessment in dementia. Performance on psychometric tests is key to diagnosis and monitoring of dementia. NIRT can be used to improve the psychometric properties of tests used in dementia assessment in multiple ways: confirming an underlying unidimensional structure, establishing formal item hierarchical patterns of decline, increasing insight by examining item parameters such as difficulty and discrimination, and creating shorter tests. From a NIRT approach item difficulty refers to the ease with which an item is endorsed. Discrimination is an index of how well an item can differentiate between patients of varying levels of severity. Firstly I carried out a systematic review to identify applications of both parametric and non-parametric IRT to measures assessing global cognitive functioning in people with dementia. This review demonstrated that IRT can increase the interpretive power of cognitive assessment scales and confirmed the limited number of IRT analyses of cognitive scales in dementia populations. This thesis extended this approach by applying Mokken scaling analysis to commonly used measures of current cognitive ability (Addenbrooke’s Cognitive Examination-Revised (ACE-R)) and of premorbid cognitive ability (National Adult Reading Test (NART)). Differential item functioning (DIF) by diagnosis identified slight variations in the patterns of hierarchical decline in the ACE-R. These disease-specific sequences of decline could serve as an adjunct to diagnosis, for example where learning a name and address is a more difficult task than being orientated in time, late onset Alzheimer’s disease is a more probable diagnosis than mixed Alzheimer’s and vascular dementia. These analyses also allowed key items to be identified which can be used to create briefer scales (mini-ACE and Mini-NART) which have good psychometric properties. These scales are clinically relevant, comprising highly discriminatory, invariantly ordered items. They also allow sensitive measurement and adaptive testing and can reduce test administration time and patient stress. Impairment of functional abilities represents a crucial component of dementia diagnosis with performance on these functional tasks predictive of overall disease. A second aspect of this thesis, therefore, was the application of Mokken scaling analyses to measures of functional decline in dementia, specifically the Lawton Instrumental Activities of Daily Living (IADL) scale and Physical Self-Maintenance Scale (PSMS). While gender DIF was observed for several items, implying the likelihood of equal responses from men and women is not equal a generally consistent pattern of impairment in functional ability was observed across different types of dementia.

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15

Chou, Yen-Liang. "Relaxation phenomena during non-equilibrium growth." Diss., Virginia Tech, 2011. http://hdl.handle.net/10919/28574.

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The surface width, a global quantity that depends on time, is used to characterize the temporal evolution of growing surfaces. One of the most successful concepts for describing the property of the surface width is the famous Family-Vicsek scaling relation. We discuss an extended scaling relation that yields a complete description for various growth models. For two linear Langevin equations, namely the Edwards-Wilkinson equation and the Mullins-Herring equation, we furthermore study analytically the behavior of global quantities related to the surface width or to a quantity which is conjugated to the diffusion constant. The global quantities depend in a non-trivial way on two different times. We discuss the dynamical scaling forms of global correlation and response functions. For global functions related to the surface width, we show that the scaling behavior of the response can depend on how the system is perturbed. Different dynamic regimes, characterized by a power-law or by an exponential relaxation, are identified, and a dynamic phase diagram is constructed. We discuss global fluctuation-dissipation ratios and how to use them for the characterization of non-equilibrium growth processes. We also numerically study the same two-time quantities for the non-linear Kardar-Parisi-Zhang equation. For global functions related to the quantity which is conjugated to the diffusion constant of the linear Langevin equations, we show that the integrated response is proportional to the correlation in the linear response regime. In the aging regime, the autocorrelation and autoresponse exponents are identical and the aging exponent for the response is equal to the aging exponent for the correlation. We investigate the non-equilibrium fluctuation-dissipation theorem for non-equilibrium states based on this quantity. In the non-linear response regime a certain dissipation-fluctuation ratio approximates unity for small waiting times but approaches the ratio of perturbed and unperturbed diffusion constants for larger waiting times.
Ph. D.

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16

Joseph, Annelise K. "All for One But Not One for All| Excitatory Synaptic Scaling and Intrinsic Excitability are Coregulated by Camkiv, While Inhibitory Synaptic Scaling is Under Independent Control." Thesis, Brandeis University, 2017. http://pqdtopen.proquest.com/#viewpdf?dispub=10276021.

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Despite being comprised of networks with extensive positive feedback, the brain is able to prevent runaway activity. Neural networks are remarkably good at maintaining an activity setpoint while still permitting learning-related or developmental plasticity. To accomplish the delicate balance between change and stability, neural networks employ a group of homeostatic negative feedback mechanisms. This suite of homeostatic mechanisms sense and adjust neuronal excitability to keep firing rates within some target range. To date, the most well described manner in which neurons homeostatically regulate their excitability is through adjustment of excitatory or inhibitory synaptic weights, or by modulating their intrinsic excitability. It is perplexing why the neuron should have several means to accomplish the same outcome. Experiments demonstrating the collaborative or solo induction of homeostatic mechanisms have provided only limited insight into how homeostatic signaling pathways are organized to generate and maintain firing rate set-points (FRSP).

In order for neurons to maintain a FRSP, deviations from this value must modulate an internal signal that subsequently triggers homeostatic mechanisms to restore excitability to its set-point. The CaMKIV pathway is a calcium-dependent signaling element that plays a crucial role in regulating excitatory synaptic strength. The CaMKIV cascade is highly sensitive to activity and can modulate transcription, making it an ideal candidate to integrate incoming activity and modulate the excitability of neurons. Therefore, the major aim of this thesis was to characterize the role of CaMKIV in inducing multiple forms of homeostatic plasticity in tandem. Here we leverage our expertise in measuring homeostasis in neocortical neurons in vitro to determine how manipulating the activation state of nuclear CaMKIV affects neuronal excitability.

We found that excitatory synaptic scaling and intrinsic plasticity were bidirectionally induced by manipulating CaMKIV activity even without any perturbations to network activity. In contrast, CaMKIV had no impact on inhibitory synaptic weights. Additionally, we found that CaMKIV activity bidirectionally regulated spontaneous firing rates. Taken together, our data suggests that CaMKIV activity is used by the neuron to monitor the firing set point and gate homeostatic mechanisms to correct for drift from this target. The data presented in this thesis contribute that excitatory synaptic scaling and intrinsic excitability are tightly coordinated through bidirectional changes in the same signaling pathway, while inhibitory synaptic scaling is sensed and regulated through an independent signaling mechanism. This body of work contributes to a better understanding of neuronal homeostasis and will hopefully help us determine how malfunctions in homeostatic plasticity contributes to neurological and neurodevelopmental disorders.

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17

Sheehy, Suzanne Lyn. "Design of a non-scaling fixed field alternating gradient accelerator for charged particle therapy." Thesis, University of Oxford, 2010. http://ora.ox.ac.uk/objects/uuid:d9cd977c-35db-45cc-ad33-67710fc3e82f.

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This thesis describes the design a novel type of particle accelerator for charged particle therapy. The accelerator is called a non-scaling, Fixed Field Alternating Gradient (ns-FFAG) accelerator, and will accelerate both protons and carbon ions to energies required for clinical use. The work is undertaken as part of the PAMELA project. An existing design for a ns-FFAG is taken as a starting point and analysed in terms of its ability to suit the charged particle therapy application. It is found that this design is particularly sensitive to alignment errors and would be unable to accelerate protons and carbon ions at the proposed acceleration rate due to betatron resonance crossing phenomena. To overcome this issue, a new type of non-linear ns-FFAG is developed which avoids resonance crossing and meets the requirements provided by clinical considerations. Two accelerating rings are required, one for protons up to 250 MeV and fully stripped carbon ions to 68 MeV/u, the other to accelerate the carbon ions up to 400-430 MeV/u. Detailed studies are undertaken to show that this new type of accelerator is suitable for the application. An alignment accuracy of 50 micrometers will not have a detrimental effect on the beam and the dynamic aperture for most lattice configurations is found to be greater than 50 pi.mm.mrad normalised in both the horizontal and vertical plane. Verification of the simulation code used in the PAMELA lattice design is carried out using experimental results from EMMA, the world's first ns-FFAG for 10-20 MeV electrons built at Daresbury Laboratory, UK. Finally, it is shown that the described lattice can translate into realistic designs for the individual components of the accelerator. The integration of these components into the PAMELA facility is discussed.

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18

Mura, Federica [Verfasser], and Chase [Akademischer Betreuer] Broedersz. "Non-equilibrium scaling behavior in stochastically driven biological assemblies / Federica Mura ; Betreuer: Chase Broedersz." München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2019. http://d-nb.info/1199265780/34.

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19

Abrahamsson, Andreas. "Using Function as a Service for Dynamic Application Scaling in the Cloud." Thesis, Uppsala universitet, Avdelningen för beräkningsvetenskap, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-347145.

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Function as a Service is a new addition to cloud services that allow a user to execute code in form of a function, in the cloud. All underlying complexity is handled by the cloud provider and the user only pay per use. Cloud services have been growing significantly over the past years and many companies want to take advantages of the benefits of the cloud. The cloud services deliver computing resources as a service over a network connection, often by the Internet. To use the benefit of the cloud, one can not just move an application to the cloud and think that it will solve itself. First of all, an application needs to be optimized to be able to take advantages of the cloud. Therefore, together with Tieto, a microservice architecture have been the main architectural pattern when Function as a Service has been evaluated. A major problem with applications, both application built with a monolithic and microservice architecture, is to handle great amounts of information flows. An application may have scaling issues when an information flow becomes too large. A person using Function as a Service does not have to buy, rent or maintain their own servers. However, Function as a Service has a certain memory and runtime restrictions, so an entire application cannot be applied to a Function as a Service. This thesis examines the possibility of using Function as a Service in different architectural environments and estimating the cost of it. Function as a Service is a new addition to cloud services, so cloud providers are also compared and evaluated in terms of the Function as a Service functionality. Function as a Service has been tested directly on various cloud platforms and even developed and executed locally, encapsulated in containers. The results show that Function as a Service is a good complement to an application architecture. The results also show that Function as a Service is highly flexible and cost-effective, and it is advantageous compared to physical servers and Virtual Machines. Depending on how a function is built, the developer can lower the cost even more by choosing the cloud supplier that fits best for their use. With the flexibility of Function as a Service, applications can handle greater information flow without bottlenecks in the infrastructure and therefore, becomes more efficient and cost-effective.

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20

Coffey, Tristan J. "Power Scaling of Ice Floe Sizes in the Weddell Sea, Southern Ocean." Wright State University / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=wright1622155717444533.

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21

Collier, E. S. "The illusion of action-specific scaling effects : action capacity does not directly influence spatial perception." Thesis, University of Liverpool, 2018. http://livrepository.liverpool.ac.uk/3018487/.

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22

Miklosovic, David Scott. "An experimental evaluation of the non-newtonian scaling effects in a rotodynamic left ventricular assist device /." The Ohio State University, 2000. http://rave.ohiolink.edu/etdc/view?acc_num=osu1488191667183226.

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23

Snguanyat, Ongorn. "Stochastic modelling of financial time series with memory and multifractal scaling." Thesis, Queensland University of Technology, 2009. https://eprints.qut.edu.au/30240/1/Ongorn_Snguanyat_Thesis.pdf.

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Financial processes may possess long memory and their probability densities may display heavy tails. Many models have been developed to deal with this tail behaviour, which reflects the jumps in the sample paths. On the other hand, the presence of long memory, which contradicts the efficient market hypothesis, is still an issue for further debates. These difficulties present challenges with the problems of memory detection and modelling the co-presence of long memory and heavy tails. This PhD project aims to respond to these challenges. The first part aims to detect memory in a large number of financial time series on stock prices and exchange rates using their scaling properties. Since financial time series often exhibit stochastic trends, a common form of nonstationarity, strong trends in the data can lead to false detection of memory. We will take advantage of a technique known as multifractal detrended fluctuation analysis (MF-DFA) that can systematically eliminate trends of different orders. This method is based on the identification of scaling of the q-th-order moments and is a generalisation of the standard detrended fluctuation analysis (DFA) which uses only the second moment; that is, q = 2. We also consider the rescaled range R/S analysis and the periodogram method to detect memory in financial time series and compare their results with the MF-DFA. An interesting finding is that short memory is detected for stock prices of the American Stock Exchange (AMEX) and long memory is found present in the time series of two exchange rates, namely the French franc and the Deutsche mark. Electricity price series of the five states of Australia are also found to possess long memory. For these electricity price series, heavy tails are also pronounced in their probability densities. The second part of the thesis develops models to represent short-memory and longmemory financial processes as detected in Part I. These models take the form of continuous-time AR(∞) -type equations whose kernel is the Laplace transform of a finite Borel measure. By imposing appropriate conditions on this measure, short memory or long memory in the dynamics of the solution will result. A specific form of the models, which has a good MA(∞) -type representation, is presented for the short memory case. Parameter estimation of this type of models is performed via least squares, and the models are applied to the stock prices in the AMEX, which have been established in Part I to possess short memory. By selecting the kernel in the continuous-time AR(∞) -type equations to have the form of Riemann-Liouville fractional derivative, we obtain a fractional stochastic differential equation driven by Brownian motion. This type of equations is used to represent financial processes with long memory, whose dynamics is described by the fractional derivative in the equation. These models are estimated via quasi-likelihood, namely via a continuoustime version of the Gauss-Whittle method. The models are applied to the exchange rates and the electricity prices of Part I with the aim of confirming their possible long-range dependence established by MF-DFA. The third part of the thesis provides an application of the results established in Parts I and II to characterise and classify financial markets. We will pay attention to the New York Stock Exchange (NYSE), the American Stock Exchange (AMEX), the NASDAQ Stock Exchange (NASDAQ) and the Toronto Stock Exchange (TSX). The parameters from MF-DFA and those of the short-memory AR(∞) -type models will be employed in this classification. We propose the Fisher discriminant algorithm to find a classifier in the two and three-dimensional spaces of data sets and then provide cross-validation to verify discriminant accuracies. This classification is useful for understanding and predicting the behaviour of different processes within the same market. The fourth part of the thesis investigates the heavy-tailed behaviour of financial processes which may also possess long memory. We consider fractional stochastic differential equations driven by stable noise to model financial processes such as electricity prices. The long memory of electricity prices is represented by a fractional derivative, while the stable noise input models their non-Gaussianity via the tails of their probability density. A method using the empirical densities and MF-DFA will be provided to estimate all the parameters of the model and simulate sample paths of the equation. The method is then applied to analyse daily spot prices for five states of Australia. Comparison with the results obtained from the R/S analysis, periodogram method and MF-DFA are provided. The results from fractional SDEs agree with those from MF-DFA, which are based on multifractal scaling, while those from the periodograms, which are based on the second order, seem to underestimate the long memory dynamics of the process. This highlights the need and usefulness of fractal methods in modelling non-Gaussian financial processes with long memory.

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24

Snguanyat, Ongorn. "Stochastic modelling of financial time series with memory and multifractal scaling." Queensland University of Technology, 2009. http://eprints.qut.edu.au/30240/.

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Financial processes may possess long memory and their probability densities may display heavy tails. Many models have been developed to deal with this tail behaviour, which reflects the jumps in the sample paths. On the other hand, the presence of long memory, which contradicts the efficient market hypothesis, is still an issue for further debates. These difficulties present challenges with the problems of memory detection and modelling the co-presence of long memory and heavy tails. This PhD project aims to respond to these challenges. The first part aims to detect memory in a large number of financial time series on stock prices and exchange rates using their scaling properties. Since financial time series often exhibit stochastic trends, a common form of nonstationarity, strong trends in the data can lead to false detection of memory. We will take advantage of a technique known as multifractal detrended fluctuation analysis (MF-DFA) that can systematically eliminate trends of different orders. This method is based on the identification of scaling of the q-th-order moments and is a generalisation of the standard detrended fluctuation analysis (DFA) which uses only the second moment; that is, q = 2. We also consider the rescaled range R/S analysis and the periodogram method to detect memory in financial time series and compare their results with the MF-DFA. An interesting finding is that short memory is detected for stock prices of the American Stock Exchange (AMEX) and long memory is found present in the time series of two exchange rates, namely the French franc and the Deutsche mark. Electricity price series of the five states of Australia are also found to possess long memory. For these electricity price series, heavy tails are also pronounced in their probability densities. The second part of the thesis develops models to represent short-memory and longmemory financial processes as detected in Part I. These models take the form of continuous-time AR(∞) -type equations whose kernel is the Laplace transform of a finite Borel measure. By imposing appropriate conditions on this measure, short memory or long memory in the dynamics of the solution will result. A specific form of the models, which has a good MA(∞) -type representation, is presented for the short memory case. Parameter estimation of this type of models is performed via least squares, and the models are applied to the stock prices in the AMEX, which have been established in Part I to possess short memory. By selecting the kernel in the continuous-time AR(∞) -type equations to have the form of Riemann-Liouville fractional derivative, we obtain a fractional stochastic differential equation driven by Brownian motion. This type of equations is used to represent financial processes with long memory, whose dynamics is described by the fractional derivative in the equation. These models are estimated via quasi-likelihood, namely via a continuoustime version of the Gauss-Whittle method. The models are applied to the exchange rates and the electricity prices of Part I with the aim of confirming their possible long-range dependence established by MF-DFA. The third part of the thesis provides an application of the results established in Parts I and II to characterise and classify financial markets. We will pay attention to the New York Stock Exchange (NYSE), the American Stock Exchange (AMEX), the NASDAQ Stock Exchange (NASDAQ) and the Toronto Stock Exchange (TSX). The parameters from MF-DFA and those of the short-memory AR(∞) -type models will be employed in this classification. We propose the Fisher discriminant algorithm to find a classifier in the two and three-dimensional spaces of data sets and then provide cross-validation to verify discriminant accuracies. This classification is useful for understanding and predicting the behaviour of different processes within the same market. The fourth part of the thesis investigates the heavy-tailed behaviour of financial processes which may also possess long memory. We consider fractional stochastic differential equations driven by stable noise to model financial processes such as electricity prices. The long memory of electricity prices is represented by a fractional derivative, while the stable noise input models their non-Gaussianity via the tails of their probability density. A method using the empirical densities and MF-DFA will be provided to estimate all the parameters of the model and simulate sample paths of the equation. The method is then applied to analyse daily spot prices for five states of Australia. Comparison with the results obtained from the R/S analysis, periodogram method and MF-DFA are provided. The results from fractional SDEs agree with those from MF-DFA, which are based on multifractal scaling, while those from the periodograms, which are based on the second order, seem to underestimate the long memory dynamics of the process. This highlights the need and usefulness of fractal methods in modelling non-Gaussian financial processes with long memory.

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25

Frota, Nicolly Parente Ribeiro. "Effects of Tiludronate Administration as an Adjunctive to Mechanical Periodontal Treatment or not in Experimental Periodontitis in Rats." Universidade Federal do CearÃ, 2013. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=10150.

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CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior
Background and Objectives: The proven efficacy of bisphosphonates to inhibit the osteoclastic bone resorption has led to their use in the management of periodontal diseases. This dissertation, comprised by 2 manuscripts, aimed: (1) to histologically analyze the effects of systemic administration of Tiludronate (TIL) on ligature-induced periodontitis in rats; (2) to histologically analyze the effects of systemic administration of TIL as an adjunctive therapy to mechanical periodontal treatment on ligature-induced periodontitis in rats. Methods: In study 1, 32 adult male rats were divided into four groups (n=8): C, PD, PD-TIL5, PD-TIL15 (CâControl group, PDâPeriodontitis groups). On PD groups, a ligature was placed in the cervical area of the right mandibular 1st molar of each rat. After 15 days, TIL solutions (TildrenÂ, Ceva SaÃde Animal Ltda., PaulÃnia, SP, Brazil) at dosages of 5 mg/kg body weight (group PD-TIL5) or 15 mg/kg body weight (group PD-TIL15) were subcutaneously administered 5 times a week for 3 weeks. In study 2, 40 adult male rats were divided into five groups (n=8): C, PD, PDT, PDT-TIL 5, PDT-TIL 15. On PD groups, ligatures were placed as described. After 15 days, ligatures of the rats from groups PDT, PDT-TIL5 and PDT-TIL15 were removed and scaling and root planing were performed. TIL solutions at dosages of 5 mg/kg body weight (group PDT-TIL5) or 15 mg/kg body weight (group PDT-TIL15) were subcutaneously administered 5 times a week for 3 weeks. All animals were euthanized at the 36th day. Histometric and histologic analyses were performed. Data were statistically analyzed (ANOVA, Tukey, p<0.05). Results: In study 1, alveolar bone loss was significantly reduced in group PD-TIL5 (1.12 mmÂ0.24), when compared with groups PD (1.70 mmÂ0.32) and PD-TIL15 (1.47 mmÂ0.21). The animals from all PD groups presented more periodontal attachment loss than the ones from group C (0.12 mmÂ0.09). There were no differences in periodontal attachment loss among PD groups (PD: 0.53 mmÂ0.19; PD-TIL5: 0.37 mmÂ0.09; PD-TIL15: 0.52 mmÂ0.13). In study 2, there were no differences in alveolar bone losses among groups PDT (1.27 mmÂ0.15), PDT-TIL 5 (1.18 mmÂ0.10) and PDT-TIL 15 (1.26 mmÂ0.40). The alveolar bone losses found in these groups were slighter than the alveolar bone loss observed in group PD and did not statistically differ from the alveolar bone loss found in group C. Animals from all groups with periodontitis induction (group PD: 0.59 mmÂ0.16; group PDT: 0.39 mmÂ0.07; group PDT-TIL 5: 0.42 mmÂ0.05; group PDT-TIL 15: 0.48 mm Â 0.09) presented periodontal attachment losses statistically greater than the animals from group C (0.12 mmÂ0.09). Groups PDT and PDT-TIL 5 presented less periodontal attachment loss than group PD. Conclusions: Within the limits of this study, it can be concluded that (i) systemically-administered TIL solution reduced alveolar bone loss in established periodontitis in rats, (ii) dosage of TIL may influence its anti-inflammatory and anti-resorptive properties and (iii) systemically-administered TIL did not result in additional benefits to periodontal mechanical therapy in rats with experimental periodontitis.
IntroduÃÃo e Objetivos: A eficÃcia comprovada dos bisfosfonatos em inibir a reabsorÃÃo Ãssea osteoclÃstica levou Ã utilizaÃÃo dos mesmos no tratamento da periodontite. Esta dissertaÃÃo, composta por 2 artigos, teve como objetivos: (1) avaliar, histologicamente, os efeitos da administraÃÃo sistÃmica do bisfosfonato Tiludronato (TIL) na periodontite induzida por ligadura em ratos; (2) avaliar, histologicamente, os efeitos da administraÃÃo sistÃmica do TIL como terapia adjuvante ao tratamento periodontal mecÃnico na periodontite induzida por ligadura em ratos. MÃtodos: No estudo 1, 32 ratos adultos machos foram divididos em 4 grupos (n=8): C, DP, DP-TIL5 e DP-TIL15 (C-grupo Controle, DP-grupos Periodontite). Nos grupos DP, ligaduras foram colocadas na Ãrea cervical dos 1os molares inferiores direitos de cada um dos ratos no 1Â dia. ApÃs 15 dias, soluÃÃes de TIL (TildrenÂ, Ceva SaÃde Animal Ltda., PaulÃnia/SP, Brasil) nas dosagens de 5 mg/kg de peso corporal (grupo DP-TIL5) e 15 mg/kg de peso corporal (grupo DP-TIL15) foram administradas, 5 vezes por semana, durante 3 semanas. No estudo 2, 40 ratos adultos machos foram divididos em 5 grupos (n=8): C, DP, DPT, DPT-TIL5 e DPT-TIL15. Nos grupos DP, foram colocadas ligaduras, conforme descriÃÃo anterior. ApÃs 15 dias, as ligaduras dos ratos dos grupos DPT, DPT-TIL5 e DPT-TIL15 foram removidas, e foram realizados raspagem e alisamento radicular. SoluÃÃes de TIL nas dosagens de 5 mg/kg de peso corporal (DPT-TIL5) e 15 mg/kg de peso corporal (DPT-TIL15) foram administradas, 5 vezes por semana, durante 3 semanas. Os animais foram submetidos Ã eutanÃsia no 36Â dia. Foram realizadas anÃlises histolÃgica qualitativa e histomÃtrica. Os dados obtidos foram analisados estatisticamente (ANOVA, Tukey, p< 0,05). Resultados: No estudo 1, a perda Ãssea alveolar foi significativamente reduzida no grupo DP-TIL5 (1,12 mmÂ0,24), quando comparada Ã dos grupos DP (1,70 mmÂ0,32) e DP-TIL15 (1,47 mmÂ0,21). Os animais dos grupos DP apresentaram maior perda de inserÃÃo quando comparados aos do grupo C (0,12 mmÂ0,09). NÃo houve diferenÃas na perda de inserÃÃo entre os grupos DP (DP: 0,53 mmÂ0,19; DP-TIL5: 0,37 mmÂ0,09; DP-TIL15: 0,52 mmÂ0,13). No estudo 2, nÃo houve diferenÃas na perda Ãssea alveolar entre os grupos DPT (1,27 mmÂ0,15), DPT-TIL 5 (1,18 mmÂ0,10) e DPT-TIL 15 (1,26 mmÂ0,40). A perda Ãssea alveolar observada nesses grupos foi menor que a do grupo DP e nÃo diferiu estatisticamente da perda Ãssea alveolar encontrada no grupo C. Todos os animais dos grupos com ligadura (grupo DP: 0,59 mmÂ0,16; grupo DPT: 0,39 mmÂ0,07; grupo DPT-TIL 5: 0,42 mmÂ0,05; grupo DPT-TIL 15: 0,48 mm Â 0,09) apresentaram perdas de inserÃÃo estatisticamente maiores que os animais do grupo C (0,12 mmÂ0,09). Os grupos DPT e DPT-TIL 5 apresentaram menor perda de inserÃÃo que o grupo DP. ConclusÃes: Dentro dos limites deste estudo, pode ser concluÃdo que (i) a administraÃÃo sistÃmica de TIL reduziu a perda Ãssea alveolar na periodontite estabelecida em ratos; (ii) a dosagem do TIL pode influenciar suas propriedades antirreabsortivas e anti-inflamatÃrias; (iii) a administraÃÃo sistÃmica de TIL nÃo proporcionou benefÃcios adicionais Ã terapia periodontal mecÃnica em ratos com periodontite experimental.

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26

Clark, Mark A. "Dynamic Voltage/Frequency Scaling and Power-Gating of Network-on-Chip with Machine Learning." Ohio University / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1544105215810566.

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27

Nandi, Riya. "Non-equilibrium dynamics in three-dimensional magnetic spin models and molecular motor-inspired one-dimensional exclusion processes." Diss., Virginia Tech, 2021. http://hdl.handle.net/10919/102652.

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We investigate the relaxation dynamics of two distinct non-equilibrium processes: relaxation of three-dimensional antiferromagnetic lattice spin models with Heisenberg interaction following a critical quench, and a one-dimensional exclusion process inspired by the gear-like motion of molecular motors. In a system of three-dimensional Heisenberg antiferromagnets the non-conserved staggered magnetization components couple non-trivially to the conserved magnetization densities inducing fully reversible terms that enter the Langevin dynamic equation. We simulate the exact microscopic dynamics of such a system of antiferromagnets by employing a hybrid simulation algorithm that combines the reversible spin precession implemented by the fourth-order Runge-Kutta integration method with the standard relaxational dynamics at finite temperatures using Monte Carlo updates. We characterize the dynamic universality class of this system by probing the early temporal window where the system exhibits aging scaling properties. We also verify an earlier renormalization group prediction that the temporal decay exponent in the two-time spin autocorrelation function exhibits non-universality, specifically it depends on the width of the initial spin orientation distribution. We employ a similar numerical technique to study the critical dynamics of an anisotropic Heisenberg antiferromagnet in the presence of an external field. The phase diagram of this system exhibits two critical lines that meet at a bicritical point. We study the aging scaling dynamics for the model C critical line, probe the model F critical line by investigating the system size dependence of the characteristic spin-wave frequencies near criticality, and measure the dynamic critical exponents for the order parameter including its aging scaling at the bicritical point. We introduce a one-dimensional non-equilibrium lattice gas model representing the processive motion of dynein molecular motors over the microtubule. We study both dynamical and stationary state properties for the model consisting of hardcore particles hopping on the lattice with variable step sizes. We find that the stationary state gap-distribution exhibits striking peaks around gap sizes that are multiples of the maximum step size, for both open and periodic boundary conditions, and verify this using a mean-field calculation. For open boundary conditions, we observe intriguing damped oscillator-like distribution of particles over the lattice with a periodicity equal to the maximum step size. To characterize transient dynamics, we measure the mean square displacement that shows weak superdiffusive growth with exponent γ≈ 1.34 for periodic boundary and ballistic growth ( γ≈ 2) for open boundary conditions at early times. We also study the effect of Langmuir dynamics on the density profile.
Doctor of Philosophy
Most systems found in nature are out of equilibrium. In this dissertation we investigate the relaxation dynamics of two such non-equilibrium systems: 1. We investigate a three-dimensional antiferromagnetic system relaxing towards equilibrium from an initial state that is driven far away from equilibrium at the point in the parameter space where the system undergoes a second-order phase transition. We devise a novel simulation method that captures emerging dynamic universal features and scaling features at these points of continuous phase transition in the early times of relaxation when the system is still far away from equilibrium. 2. Cytoplasmic dyneins are one of three kinds of motor proteins that move on tubular structures called microtubules carrying and transporting cellular cargo inside the cells. Unlike the other molecular motors that move forward with fixed step sizes, the dyneins have been experimentally observed to vary their step size depending on the amount of cargo they are carrying. We model an exclusion process in a one-dimensional lattice inspired by the motion of the dynein molecular motors where the motors can hop from one to four steps depending on their internal states. We study the effect of this variable step size on the dynamics of a collection of dyneins. We observe intriguing oscillating density profiles and discrete peaks in the distribution of empty sites. Our results suggest self-organization among the motors and the empty sites.

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28

Lange, Ryan. "Color Naming, Multidimensional Scaling, and Unique Hue Selections in English and Somali Speakers Do Not Show a Whorfian Effect." The Ohio State University, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=osu1449158554.

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29

Schmied, Christian-Marcel [Verfasser], and Thomas [Akademischer Betreuer] Gasenzer. "Universal scaling dynamics at non-thermal fixed points in multi-component Bose gases far from equilibrium / Christian-Marcel Schmied ; Betreuer: Thomas Gasenzer." Heidelberg : Universitätsbibliothek Heidelberg, 2020. http://d-nb.info/1212729404/34.

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30

Anane-Taabeah, Gifty. "Harnessing the opportunities and overcoming constraints to widespread adoption of cage aquaculture in Ghana." Thesis, Virginia Tech, 2012. http://hdl.handle.net/10919/32548.

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Understanding cage aquaculture adoption decisions and factors affecting adoption is necessary to ensure that fish production from cage aquaculture in Ghana is both significant and sustainable. The goal of this study was to provide a framework for understanding cage aquaculture adoption decisions and to identify factors affecting adoption, to inform decision makers as they formulate policies aimed at promoting cage aquaculture adoption in Ghana. I surveyed 122 respondents comprising current cage fish farmers, farmers who have abandoned cage aquaculture, and potential adopters of cage aquaculture such as, fish traders, fishermen and land-based fish farmers. Respondents answered questions related to knowledge, interest, constraints in cage aquaculture, and demographics. I used non-metric multidimensional scaling and discriminant function analysis to identify unique groups within the respondents, classify respondents according to their position in the innovation-decision continuum, and identify factors affecting cage aquaculture adoption. Based on their differences in knowledge and interests, I placed respondents into one of three stages of the cage aquaculture innovation-decision process model I developed: (1) Unawareness, (2) Knowledge, Persuasion, and Decision (KPD), and (3) Implementation (Confirmation and Abandonment). Respondents in the KPD and Implementation stages had knowledge, were more interested in cage aquaculture, and were aware of constraints in cage aquaculture, whereas respondents in the Unawareness stage lacked knowledge and interest in cage aquaculture, and did not clearly understand the constraints. Respondents who were males, belonged to the tribes Ewe and Akan, and who had fishing experience tended to be more interested in cage aquaculture. The lack of capital, high input costs, inability to adequately market fish, theft, lack of information sources, conflict over water use, and cage destruction by storms, were identified as the main constraints to cage aquaculture adoption in Ghana. The results of the study suggest that programs aimed at encouraging new entrants into cage aquaculture should focus on demographic characteristics such as gender, and tribe. However, demographic characteristics may affect adoption decisions and it may be important to consider them as such. Some recommendation to address the major constraints in cage aquaculture include: the Fisheries Directorate should (1) develop an efficient extension program that farmers can access regularly, especially, for farmers with no other information sources, (2) provide feed subsidy to enable farmers produce fish at competitive prices, (3) facilitate the formation of fish farmersâ cooperative groups that would purchase large quantities of feed, (4) encourage local production of high quality fish feed, and (5) develop credit facilities that can be accessed by individuals interested in cage aquaculture to assist potential farmers who would, otherwise, not be able to adopt cage aquaculture . In addition, fish farmers should (6) be proactive in marketing their fish by identifying potential niche markets prior to production, and (7) join cooperative groups to ease the burden of accessing loans to increase production.
Master of Science

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31

Harby, Galal Abd El-Haleem. "A non-metric multidimensional scaling analysis of customers' attitudes to life insurance : an empirical investigation of insured vs. non-insured attitudes towards life insurance purchasing decision variables in Egypt." Thesis, University of Sheffield, 1986. http://etheses.whiterose.ac.uk/14762/.

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This study is an investigation of the variables which determine life insurance purchasing decisions in Egypt. More precisely, the interest is focused on the customers' attitudes towards purchasing life insurance, as well as on demographic/socioeconomic factors that are assumed to influence the decision to purchase. It is hypothesized that: A) Attitudes towards life insurance purchasing decision variables are similar (i.e., there is no difference) for both insured and non-insured typologies; B) the importance attached to saving through life insurance is similar to that attached to saving with the other financial institutions; and C) there is no significant relationship between the insured's demographic/socioeconomic characteristics, and the amount of life insurance purchased. The design of the research is by facets. The faceted design permits the whole universe of content under investigation to be observed and a limited content of this universe to be systematically sampled. The data is collected by means of personally administered interview questionnaires to 300 respondents (150 insured and 150 non-insured) . Since the data collected is of two major different groups of variables (i.e., attitudinal and categorical), two different techniques of analysis are employed. The first group (attitudinal) is non-metric, i.e" ordinal scaled, multivariate, and interdependent data, whereas the second group (categorical) is multivariate and dependent data of both nominal and interval types. Therefore, the decision was made to use the Non-metric Multidimensional Scaling (NMS) technique for the analysis of the attitudinal data, whereas the Multiple Classification Analysis (MCA) was found to be the most appropriate one for the categorical data. The MINISSA computer program output employed in this study, investigates the similarities and dissimilarities between the two typolcgies' (insured and non-insured) attitudes to life insurance purchasing decision variables. A Wilcoxon test has been employed to investigate the significance of hypotheses A and B, whereas F-ratio test is used for testing hypothesis c. A Kendall correlation analysis is also carried out on the relationship between the variables that are assumed to determine the life insurance purchasing decisions. The research conclusions are: i) the two typologies are similar in their (average) expressed attitudes to life insurance purchasing decision variables; ii) the most important reasons for purchasing life insurance (by both typologies) are: 1) the protection of dependents; 2) saving purposes for daughters' marriage costs; and 3) retirement income/old age protection; iii) the most desirable financial facilities (offered by the insurer) are: 1) profit sharing; 2) borrowing against the cash value of the policy; and 3) the guarantee of surrender values; iv) the most important financial aspects for purchasing life insurance are: 1) a small amount of money being invested; 2) safety for money; and 3) provision against inflation. The significantly different attitudes expressed by the two typologies are those with regard to the importance attached to having life insurance against saving with the other financial institutions. It is concluded that the most distinctive function of life insurance programmes is to cover risks (protection element), whereas saving with the other financial institutions is considered to be of more importance where the purpose(s) is to get a high return on investments and/or saving for emergency situations. The findings on the MCA output show that the selected predictors account for a relatively high proportion of the variance in the amount of life insurance purchased (R2 = 55%). However, the most important explanatory variable is found to be current income. The investigation finally concludes by suggesting the potential applications of these research findings for the process of decision making in the life insurance marketing management in Egypt.

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32

Puglisi, Rosario. "Evaluation of instrumentation systems for periodontal mechanical treatment." Doctoral thesis, Universitat Internacional de Catalunya, 2017. http://hdl.handle.net/10803/461097.

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A major objective in the treatment of periodontitis is to reduce supra-gingival and sub-gingival plaque, dental calculus, and prevent recolonization of periodontal pockets by pathogenic bacteria{{117 Braun,A. 2005; 118 Dragoo,M.R. 1992; 119 Kocher,T. 2000; 120 Loos,B. 1987;}}. It is important for the clinician to achieve a controlled surface free of calculus and an optimal oral hygiene control by patients{{88 Keogh,T.P. 1993; 90 Alves,R.V. 2004; 89 Alves,R.V. 2005;}}. Previous studies have reported beneficial results from scaling and root planning in both clinical and microbiological aspects.{{139 Caffesse,R.G. 1986; 140 Huerzeler,M.B. 1998; 141 Leknes,K.N. 1994; 120 Loos,B. 1987; 143 Quirynen,M. 1990;}} The aim of this study is to provide new and relevant data on scaling and root planing methods in order to value the effectiveness (different changes in plaque index, probing pocket depth, attachment level, and bleeding on probing) and the morbidity of four different instrumentation systems (sensitivity and pain). The main objective is to analyze individually each instrument to analyze the effectiveness and the morbidity; the secondary objective is to compare the various instrumentation systems with the "gold standard" for scaling and root planing (Curettes + Ultrasound). Objectives: The results of this study will provide new relevant data on scaling and root planing methods. Main Objective: The main objective is to analyze the clinical effectiveness of 4 different instrumentation systems and compare the results, in terms of clinical attachment level gain, to non surgical periodontal therapy (periodontal debridement). Secondary Objectives: 1. To analyze the post-treatment morbidity for each method. 2. To analyze the working-time for each method. Focus of the Thesis to achieve the objectives: This in vivo study compared the effectiveness and morbidity of four different instruments using a split mouth design. Patients were chosen at the first visit to the department of Periodontology of the Dental Clinic of the Universitat Internacional de Catalunya UIC. On the first visit patients underwent a comprehensive periodontal examination. The operator carried out an initial examination of the patient and filled out a questionnaire relevant to the patient’s general information. A Periodontal examination was performed with a periodontal probe (HU-Friedy® - Chicago.IL.USA - COD: PCPUNC15 30 - CP15) and a periodontal chart used in the University Dental Clinic . The following parameters were examined: - plaque index (PI) {{171 O'Leary,T.J. 1972;}} - probing pocket depth (PPD) - probing attachment level (PAL) - bleeding on probing (BOP) {{170 Benamghar,L. 1982;}} - gingival recession (REC): measurement from the cementum-enamel junction to the gingival marginal crest - mobility (MOB) (Miller 1950) - furcation involvement (FI) (Hamp et al. 1975) - sensitivity (tested by the operator) After completion of initial screening, each patient (that met the selection criteria) was informed about his/her periodontal status and the clinical study. Each patient agreed to participate by signing a consent form. No patient was admitted to the study until the Informed Consent Form is signed. Twenty (20) patients were selected to obtain the statistical significance of the results and the analyses was performed using a statistical program (Stratigrafics for Windows). A power calculation before the initiation of this study revealed that a sample size of 17 patients was necessary to detect a difference of 1 mm for each clinical parameter, assuming a maximal mean - standard deviation of 1 mm. Inclusion criteria: - Patients with generalized moderate to severe chronic periodontitis - PPD : at least two sites with probing depth ≥4mm per multi-rooted teeth, and at least three sites with probing depth ≥4mm for all remaining teeth, per quadrant. (like in other studies) (44). - Systemically healthy patient Exclusion criteria - Patients who had had antibiotic therapy in the last 2 month or during the study - Patient less of 18 years old - Smokers - Pregnant woman - Remaining dentition of less than 20 teeth - Recent periodontal treatment - Allergies to local anesthetics - Physically handicapped subject and/or with mental disorders, who cannot assume proper plaque control - Aggressive periodontitis - Acute periodontal or endodontic infection - Systemic disease: - Cardiovascular disease: uncontrolled hypertension, stable and unstable angina, recent heart attack (<1 month), heart attack (> 1 month without symptoms), arrhythmias, heart failure. - Lung disease: chronic obstructive pulmonary disease, tuberculosis - Gastrointestinal disease: chronic active hepatitis, cirrhosis, pseudomembranous colitis, renal disease. - Genitourinary disease: chronic renal failure, sexually transmitted diseases (gonorrhea, syphilis, genital herpes, papillomavirus infection). - Endocrine and metabolic disease: diabetes mellitus, renal failure, hypothyroidism and hyperthyroidism, uncontrolled tiroiditis, thyroid cancer, pregnancy and lactation. - Immune disease: HIV infection and related conditions, connective tissue disorders (lupus erythematosus, pemphigus vulgaris, penfogoide, Sjogren's syndrome), organ transplant (heart, liver, kidney, pancreas, bone marrow). - Hematological disorders: Anemia, agranulocytosis, cyclic neutropenia, leukemia, multiple myeloma, lymphomas, thrombocytopenia, vascular wall, hemophilia, von Willebrand disease, disseminated intravascular coagulation, thrombocytopenia, primary fibrinogenolisis. - Oncological disease: patients undergoing radiotherapy and chemotherapy. - Psychiatric illness, disease of the behavior, neurological disease: epilepsy, Parkinson's syndrome, anxiety, eating disorders, delirium, schizophrenia, depression and bipolar disorder untreated. This in vivo study compared four different instruments using a split mouth design. The split mouth design selected for this study is the division of the mouth into 4 parts, each part corresponded to a quadrant. Four groups were formed (one for each instrument) and each quadrant (of each patient) was assigned to one clinically randomized group. The realization of treatment for each patient was made randomly using an informatical function of randomization. Groups Group A: curettes (Hu-Friedy®) Specific curettes were used following this plan: Gracey curettes 5/6 --- anterior teeth Gracey curettes 11/12 --- mesial surface of premolar and molar Gracey curettes 13/14 --- distal surface of premolar and molar Group B: conventional piezoelectric ultrasound (Suprasson P-5 Booster - Satelec®) was applied at a power between 11 and 12 with the insert n.1 (Satelec®). The minute vibration frequency of this ultrasound is 28-36 KHz. Group C: diamond burs 40 µm (Intensiv Perioset®) at 3,000 rpm. Group D: piezoelectric ultrasound - Piezosurgery 3 - Mectron® was applied in On/Mode Periodontics (ROOT) mode with the insert PP1 at a power between 2 and 3. The minute vibration frequency of this ultrasound is 24-36 KHz. One reevaluation visit was performed 1 week after the treatment of each quadrant and a questionnaire was used to analyze the post-treatment morbidity. During this visit only the hypersensibility of each tooth was tested with an air-stimulation by the operator. At 8 weeks a data collection was performed by an expert periodontist (A.S.) who was blinded to the study. All important parameters for this study were recorded (as we mentioned for the Periodontal examination). The pooled data at baseline and two months after instrumentation were then used for the statistical analysis. Each clinical parameter (plaque index, probing pocket depth, probing attachment level, bleeding on probing, gingival recession, mobility, furcation involvement and sensitivity) was analyzed for each group and for a comparison between the groups. The comparison of the four instrumentation systems find out the method that shows better results. Results At 8-week re-evaluation, regarding attachment level gain and probing pocket reduction, Gracey’s curettes, conventional ultrasound, and ultrasound Piezosurgery resulted statistical more effective when compared with diamond burs. Regarding to chair side time, a statistical difference was shown (p<0.001) when suprasson ultrasound and ultrasound Piezosurgery were compared with the others instruments. The post-treatment morbidity after scaling and root planning was not statistical difference for all the analysed instrumentations. The statistical difference was shown between baseline and weeks 1 and 4, and between weeks 1 and 8, and between weeks 4 and 8, when all the results were evaluated together. Better results at 8-week re-evaluation were obtained from the use of conventional ultrasonic device: 3.04 ± 2.39 (SD) but no statistical significance difference was shown (p>0.05) when compared with other groups. Conclusions Conventional Gracey curettes (Hu-Friedy®), conventional ultrasound (P-5 Booster Suprasson Satelec®) and ultrasound Piezosurgery Mectron® are more effective clinically when compared with diamond burs 40 µm (Intensiv Perioset®). The ultrasound instrumentation showed better results in terms of chair side time. Clinical Relevance The use of conventional curettes, conventional ultrasound and ultrasonic piezoelectric Mectron device prove to be more effective than 40 µm diamond burs in the non-surgical periodontal treatment.

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Thompson, Travis Hunter [Verfasser], and Christian [Akademischer Betreuer] Ochsenfeld. "Integral bounds and rigorous screening algorithms for reduced scaling in explicitly correlated, semi-numerical, and non-Hermitian quantum chemistry / Travis Hunter Thompson ; Betreuer: Christian Ochsenfeld." München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2020. http://d-nb.info/123654319X/34.

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34

Triampo, Wannapong. "Non-Equilibrium Disordering Processes In binary Systems Due to an Active Agent." Diss., Virginia Tech, 2001. http://hdl.handle.net/10919/26738.

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In this thesis, we study the kinetic disordering of systems interacting with an agent or a walker. Our studies divide naturally into two classes: for the first, the dynamics of the walker conserves the total magnetization of the system, for the second, it does not. These distinct dynamics are investigated in part I and II respectively. In part I, we investigate the disordering of an initially phase-segregated binary alloy due to a highly mobile vacancy which exchanges with the alloy atoms. This dynamics clearly conserves the total magnetization. We distinguish three versions of dynamic rules for the vacancy motion, namely a pure random walk , an ``active' and a biased walk. For the random walk case, we review and reproduce earlier work by Z. Toroczkai et. al.,~cite{TKSZ} which will serve as our base-line. To test the robustness of these findings and to make our model more accessible to experimental studies, we investigated the effects of finite temperatures (``active walks') as well as external fields (biased walks). To monitor the disordering process, we define a suitable disorder parameter, namely the number of broken bonds, which we study as a function of time, system size and vacancy number. Using Monte Carlo simulations and a coarse-grained field theory, we observe that the disordering process exhibits three well separated temporal regimes. We show that the later stages exhibit dynamic scaling, characterized by a set of exponents and scaling functions. For the random and the biased case, these exponents and scaling functions are computed analytically in excellent agreement with the simulation results. The exponents are remarkably universal. We conclude this part with some comments on the early stage, the interfacial roughness and other related features. In part II, we introduce a model of binary data corruption induced by a Brownian agent or random walker. Here, the magnetization is not conserved, being related to the density of corrupted bits }$ ho ${small .} {small Using both continuum theory and computer simulations, we study the average density of corrupted bits, and the associated density-density correlation function, as well as several other related quantities. In the second half, we extend our investigations in three main directions which allow us to make closer contact with real binary systems. These are i) a detailed analysis of two dimensions, ii) the case of competing agents, and iii) the cases of asymmetric and quenched random couplings. Our analytic results are in good agreement with simulation results. The remarkable finding of this study is the robustness of the phenomenological model which provides us with the tool, continuum theory, to understand the nature of such a simple model.
Ph. D.

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Dias, Isabel Rosa Sezinando. "Pesquisa de microrganismos nos aerossóis libertados durante o procedimento de destartarização dentária em canídeos." Master's thesis, Universidade de Lisboa. Faculdade de Medicina Veterinária, 2014. http://hdl.handle.net/10400.5/6566.

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Dissertação de Mestrado Integrado em Medicina Veterinária
A doença periodontal é a doença mais comum da cavidade oral em cães, tendo como principal etiologia a formação de placa bacteriana e de cálculo dentário. No tratamento da doença periodontal a remoção de placa bacteriana e de cálculo é feita recorrendo ao procedimento de destartarização dentária. Durante este procedimento ocorre a formação de aerossóis e gotículas, devido ao uso e aparelhos mecânicos ultrassónicos. Um dos riscos associados a este procedimento é a possibilidade de contaminação e infecção bacteriana da boca, olhos, vias respiratórias superiores e pele dos canídeos, veterinários e auxiliares. O presente estudo teve como objectivos: identificar os microrganismos presentes em amostras de aerossóis libertados durante a realização da destartarização dentária, avaliando o potencial risco de contaminação com agentes patogénicos do paciente, da sala de cirurgia, dos instrumentos utilizados e do médico veterinário e auxiliares. O estudo incluiu uma amostra aleatória de 15 canídeos com doença periodontal submetidos a destartarização dentária no Hospital Escolar da FMV. Durante o procedimento foram colhidas amostras de aerossóis, procedeu-se à sua cultura e incubação e os isoladas bacterianos foram identificados. As bactérias isoladas (n=30) foram: Pseudomonas spp. (20%); Staphylococcus spp. (13%); Escherichia coli (10%); Corynebacterium spp., Eggerthela lenta, Ralstonia pickettii e Streptococcus spp. (7%); e Actinomyces sp., Clostridium beijerinkii, Enterococcus fecalis, Morganella morganii, Pasteurella multocida, Porphyromonas asacharolytica, Prevotella sp., Proteus sp. e Vibrio vulnificus (3%). Pela primeira vez identificadas as seguintes espécies bacterianas na microbiota oral de canídeos: Staphylococcus aureus, Corynebacterium glucoronolyticum, Eggerthella lenta, Ralstonia pickettii, Clostridium beijerincki, Enterococcus fecalis, Morganella morganii, Porphyromonas assaccharolytica e Vibrio vulnificus. Pelas espécies bacterianas isoladas e identificadas no presente estudo existe o potencial de os procedimentos dentários em cães serem um risco para a saúde animal e pública, por isso devem ser tomadas medidas de higiene e prevenção na realização.
ABSTRACT - Research of microrganisms present in the aerosols released during dental scaling in dogs - Periodontal disease is the most common oral condition in dogs, being bacterial plaque and dental calculus formation its main aetiology. Mechanical scaling is used as treatment for periodontal disease by removing bacterial plaque and dental calculus. During this procedure aerosols and splatters are produced while using mechanical ultrasonic scalers. One of the hazards associated with this procedure is the contamination and infection of the mouth, eyes, upper respiratory tract and skin of dogs, veterinaries and clinical assistants. The objectives of this study were: to identify the microorganisms present in samples obtained from the aerosols produced in the dental scaling evaluating the risk of contamination by pathogenic agents of the patient, surgery room, instruments, veterinarians and clinical assistants. A random sample of 15 dogs with periodontal disease, to whom a dental scaling was performed at the FMV School Hospital, was used in this study. During the procedure of the dental scaling samples from the aerosols were collected, cultured and incubated and the isolated bacteria were identified. Isolated bacteria (n=30) were: Pseudomonas spp. (20%); Staphylococcus spp. (13%); Escherichia coli (10%); Corynebacterium spp., Eggerthela lenta, Ralstonia pickettii and Streptococcus spp. (7%); and Actinomyces sp., Clostridium beijerinkii, Enterococcus fecalis, Morganella morganii, Pasteurella multocida, Porphyromonas asacharolytica, Prevotella sp., Proteus sp. and Vibrio vulnificus (3%). For the first time the following bacterial species were identified from the oral microbiota of dogs: Staphylococcus aureus, Corynebacterium glucoronolyticum, Eggerthella lenta, Ralstonia pickettii, Clostridium beijerincki, Enterococcus fecalis, Morganella morganii, Porphyromonas assaccharolytica e Vibrio vulnificus. The bacterial species isolated and identified in this study, oral procedures in dogs represent a hazard to public and animal health, so hygiene and prevention measures must be applied.

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Albert, Samuel. "Un point critique thermodynamique dans les verres dévoilé par les réponses d'ordre élevé." Thesis, Université Paris-Saclay (ComUE), 2016. http://www.theses.fr/2016SACLS534/document.

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L'énigme de la transition vitreuse réside en grande partie dans le fait que lorsqu'un matériau entre dans l'état dit surfondu, sa dynamique ralentit de façon spectaculaire, donnant l'impression d'une transition vers un état solide, sans que pour autant on ne parvienne à constater de transition thermodynamique par les expériences usuelles.Autrement dit, on ne parvient pas à expliquer le ralentissement spectaculaire de la dynamique par la croissance d'une longueur mesurable expérimentalement.Ceci conduit à la prolifération de théories souvent contradictoires quant à l'origine de la dynamique vitreuse.Durant la dernière décennie une piste prometteuse de mise en évidence d'une telle longueur a été proposée : il s'agit de la mesure des réponses diélectriques non linéaires d'ordre 3 du matériau ainsi que de leur évolution en température. En effet, les réponses non linéaires reflètent les effets collectifs caractéristiques de l'ordre amorphe, qui ne se traduisent que dans les fonctions de corrélations d'ordre élevé.Durant cette thèse nous avons construit sur ces bases expérimentales et théoriques, une expérience de mesure des réponses non linéaires d'ordre 5. En exploitant ces résultats sur la réponse diélectrique d'ordre 5 et des résultats précédents sur la réponse d'ordre 3, nous sommes parvenus, en collaboration avec une équipe d'expérimentateurs et de théoriciens, à fournir des indices forts de l'existence d'un point critique thermodynamique dans le Glycérol et le Propylène Carbonate. Ceci constitue une avancée significative dans la compréhension des matériaux vitreux.En particulier, cette découverte permet de poser des contraintes fortes sur les théories existantes et contribue à clore certains débats théoriques ayant eu cours sur plusieurs décennies
The puzzle of the glass transition mainly resides in the fact that a supercooled liquid undergoes when cooled down, a spectacular dynamics slow down, while no evidence of any kind of thermodynamic transition has been measured through usual means.The absence of any known growth of a length scale that could explain the glassy dynamics leads to a wide range of competing models and theories trying to explain the origins of this dynamics.In the last decade, a promising lead has been put forward, that could allow the community to experimentally access such a growing length scale, through third order non-linear dielectric response measurements, and more in particular this response's temperature dependence. Indeed, non-linear response measurements reflect the collective effects that characterize the amorphous order and translate into high order correlation functions.During this PhD, we have built upon this experimental and theoretical background to design a fifth order non-linear dielectric response measurement experiment. In collaboration with a team of experimentalists and theoreticians, we have used these results in conjunction with third order response measurement results to make a very strong case advocating the existence of a thermodynamic critical point in Glycerol and Propylene Carbonate. This is a very significant advance in the understanding of the behaviour of glassy materials.This ground breaking discovery puts very strong constraints on existing theories and will contribute to end some decades-long theoretical debates within the glassy community

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Pixton, Tonya S. "Expecting Happy Women, Not Detecting the Angry Ones : Detection and Perceived Intensity of Facial Anger, Happiness, and Emotionality." Doctoral thesis, Stockholms universitet, Psykologiska institutionen, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-57167.

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Faces provide cues for judgments regarding the emotional state of individuals. Using signal-detection methodology and a standardized stimulus set, the overall aim of the present dissertation was to investigate the detection of emotional facial expressions (i.e., angry and happy faces) with neutral expressions as the nontarget stimuli. Study I showed a happy-superiority effect and a bias towards reporting happiness in female faces. As work progressed, questions arose regarding whether the emotional stimuli were equal with regard to perceived strength of emotion, and whether the neutral faces were perceived as neutral. To further investigate the effect of stimulus quality on the obtained findings, Study II was designed such that the facial stimuli were rated on scales of happy-sad, angry-friendly, and emotionality. Results showed that ‘neutral’ facial expressions were not rated as neutral, and that there was a greater perceived distance between happy and neutral faces than between angry and neutral faces. These results were used to adjust the detectability measures to compensate for the varying distances of the angry and happy stimuli from the neutral stimuli in the emotional space. The happy-superiority effect was weakened, while an angry-female disadvantage remained. However, as these results were based upon different participant groups for detection and emotional rating, Study III was designed to investigate whether the results from Studies I and II could be replicated in a design where the same participants performed both tasks. Again, the results showed the non-neutrality of ‘neutral’ expressions and that happiness was more easily detected than anger, as shown in general emotion as well as specific emotion detection. Taken together, the overall results of the present dissertation demonstrate a happy-superiority effect that was greater for female than male faces, that angry-female faces were the most difficult to detect, and a bias to report female faces as happy.
At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 1: In press. Paper 2: Manuscript. Paper 3: Manuscript.

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Idjimarene, Sonia. "Power laws behavior and nonlinearity mechanisms in mesoscopic elastic materials." Phd thesis, Université du Maine, 2013. http://tel.archives-ouvertes.fr/tel-01037944.

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Nonlinear mesoscopic elastic (NME) materials present ananomalous nonlinear elastic behavior, which could not beexplained by classical theories. New physical mechanismsshould be individuated to explain NMEs response.Dislocations in damaged metals, fluids in rocks andadhesion (in composites) could be plausible. In this thesisI have searched for differences in the macroscopic elasticresponse of materials which could be ascribed to differentphysical processes. I have found that the nonlinearindicators follow a power law behavior as a function of theexcitation energy, with exponent ranging from 1 to 3 (thisis not completely new). This allowed to classify materialsinto well-defined classes, each characterized by a value ofthe exponent and specific microstructural properties. Tolink the measured power law exponent to plausiblephysical mechanisms, I have extended thePreisach-Mayergoyz formalism for hysteresis to multi-statemodels. Specific multi-state discrete models have beenderived from continuous microscopic physical processes,such as adhesion-clapping, adhesion-capillary forces,dislocations motion and hysteresis. In each model, themicroscopic behavior is described by a multistate equationof state, with parameters which are statisticallydistributed. Averaging over many microscopic elements theso-called mesoscopic equation of state is derived and, fromwave propagation simulations in a sample composed bymany mesoscopic elements, the experimental results couldbe reproduced. In the work of the thesis, I have shownthat model predictions of the exponent b ( the exponent bhas not been introduced before) are linked in a 'a priori'predictable way to the number of states and the propertiesof the statistical distribution adopted. We have classifiedmodels into classes defined by a different exponent b andcomparing with experimental results we have suggestedplausible mechanisms for the nonlinearity generation.

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Smiseth, Jo. "Criticality and novel quantum liquid phases in Ginzburg--Landau theories with compact and non-compact gauge fields." Doctoral thesis, Norwegian University of Science and Technology, Faculty of Natural Sciences and Technology, 2005. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-583.

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We have studied the critical properties of three-dimensional U(1)-symmetric lattice gauge theories. The models apply to various physical systems such as insulating phases of strongly correlated electron systems as well as superconducting and superfluid states of liquid metallic hydrogen under extreme pressures. This thesis contains an introductory part and a collection of research papers of which seven are published works and one is submitted for publication.

Paper I: Critical properties of the 2+1-dimensional compact abelian Higgs model with gauge charge q=2 are studied. We introduce a novel method of computing the third moment M₃ of the action which allows us to extract correlation length and specific heat critical exponents ν and α without invoking hyperscaling. Finite-size scaling analysis of M₃ yields the ratio (1+α)/ν and 1/ν separately. We find that α and ν vary along the critical line of the theory, which however exhibits a remarkable resilience of Z₂ criticality. We conclude that the model is a fixed-line theory, which we propose to characterize the zero temperature quantum phase transition from a Mott-Hubbard insulator to a charge fractionalized insulator in two spatial dimensions.

Paper II: Large scale Monte Carlo simulations are employed to study phase transitions in the three-dimensional compact abelian Higgs model in adjoint representations of the matter field, labeled by an integer q, for q=2,3,4,5. We also study various limiting cases of the model, such as the Z_q lattice gauge theory, dual to the 3DZ_q spin model, and the 3D xy spin model which is dual to the Z_q lattice gauge theory in the limit q → ∞. In addition, for benchmark purposes, we study the 2D square lattice 8-vertex model, which is exactly solvable and features non-universal critical exponents. The critical exponents α and ν are calculated from finite size scaling of the third moment of the action, and the method is tested thoroughly on models with known values for these exponents. We have found that for q=3, the three-dimensional compact abelian Higgs model exhibits a second order phase transition line which joins a first order phase transition line at a tricritical point. The results for q=2 in Paper I are reported with a higher lever of detail.

Paper III: This paper is based on a talk by F. S. Nogueira in the Aachen HEP 2003 conference where a review of the results for the compact abelian Higgs model from Paper I and Paper II was presented, as well as the results for the q=1 case studied by F. S. Nogueira, H. Kleinert and A. Sudbø.

Paper IV: We study the effects of a Chern-Simons (CS) term in the phase structure of two different abelian gauge theories in three dimensions. By duality transformations we show how the compact U(1) gauge theory with a CS term for certain values of the CS coupling can be written as a gas of vortex loops interacting through steric repulsion. This theory is known to exhibit a phase transition governed by proliferation of vortex loops. We also employ Monte Carlo simulations to study the non-compact U(1) abelian Higgs model with a CS term. Finite size scaling of the third moment of the action yields critical exponents α and ν that vary continuously with the strength of the CS term, and a comparison with available analytical results is made.

Paper V: The critical properties of N-component Ginzburg-Landau theory are studied in d=2+1 dimensions. The model is dualized to a theory of N vortex fields interacting through a Coulomb and a screened potential. The model with N=2 shows two anomalies in the specific heat. From Monte Carlo simulations we calculate the critical exponents α and ν and the mass of the gauge field. We conclude that one anomaly corresponds to an inverted 3D xy fixed point, while the other corresponds to a 3D xy fixed point. There are N fixed points, namely one corresponding to an inverted 3D xy fixed point, and N-1corresponding to neutral 3D xy fixed points. Applications are briefly discussed.

Paper VI: The phase diagram and critical properties of the N-component London superconductor are studied both analytically and through large-scale Monte-Carlo simulations in d=2+1 dimensions. The model with different bare phase stiffnesses for each flavor is a model of superconductivity which should arise out of metallic phases of light atoms under extreme pressure. A projected mixture of electronic and protonic condensates in liquid metallic hydrogen under extreme pressure is the simplest example, corresponding to N=2 with individually conserved matter fields. We compute critical exponents α and ν for N=2 and N=3. The results from Paper V are presented at a higher level of detail. For the arbitrary N case, there are N fixed points,namely one charged inverted 3D xy fixed point, and N-1 neutral 3D xy fixed points. We explicitly identify one charged vortex mode and N-1 neutral vortex modes. The model for N=2 and equal bare phase stiffnesses corresponds to a field theoretical description of an easy-plane quantum antiferromagnet. In this case, the critical exponents are computed and found to be non 3D xy values. Furthermore, we study the model in an external magnetic field, and find a novel feature, namely N-1 superfluid phases arising out of N charged condensates. In particular, for N=2 we point out the possibility of two novel types of field-induced phase transitions in ordered quantum fluids: i) A phase transition from a superconductor to a superfluid or vice versa, driven by tuning an external magnetic field. This identifies the superconducting phase of liquid metallic hydrogen as a novel quantum fluid. ii) A phase transition corresponding to a quantum fluid analogue of sublattice melting, where a composite field-induced Abrikosov vortex lattice is decomposed and disorders the phases of the constituent condensate with lowest bare phase stiffness. Both transitions belong to the 3D xy universality class.

Paper VII: We consider the vortex superconductor with two individually conserved condensates in a finite magnetic field. The ground state is a lattice of cocentered vortices in both order parameters. We find two novel phase transitions when temperature is increased at fixed magnetic field. i) A "vortex sublattice melting" transition where vortices in the field with lowest phase stiffness ("light vortices") loose cocentricity with the vortices with large phase stiffness ("heavy vortices"), entering a liquid state (the structure factor of the light vortex sublattice vanishes continuously.) This transition is in the 3D xy universality class. ii) A first order melting transition of the lattice of heavy vortices in a liquid of light vortices.

Paper VIII: We report on large-scale Monte Carlo simulations of a novel type of a vortex matter phase transition which should take place in a three dimensional two-component superconductor. We identify the regime where first, at a certain temperature a field-induced lattice of co-centered vortices of both order parameters melts, causing the system to loose superconductivity. In this state the two-gap system retains a broken composite symmetry and we observe that at a higher temperature it undergoes an extra phase transition where the disordered composite one-flux-quantum vortex lines are "ionized" into a "plasma" of constituent fractional flux vortex lines in individual order parameters. This is the hallmark of the superconductor-to-superfluid-to-normal fluid phase transitions projected to occur in e.g. liquid metallic hydrogen.

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Bender, Martin. "Limit theorems for generalizations of GUE random matrices." Doctoral thesis, KTH, Matematik (Inst.), 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4799.

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This thesis consists of two papers devoted to the asymptotics of random matrix ensembles and measure valued stochastic processes which can be considered as generalizations of the Gaussian unitary ensemble (GUE) of Hermitian matrices H=A+A†, where the entries of A are independent identically distributed (iid) centered complex Gaussian random variables. In the first paper, a system of interacting diffusing particles on the real line is studied; special cases include the eigenvalue dynamics of matrix-valued Ornstein-Uhlenbeck processes (Dyson's Brownian motion). It is known that the empirical measure process converges weakly to a deterministic measure-valued function and that the appropriately rescaled fluctuations around this limit converge weakly to a Gaussian distribution-valued process. For a large class of analytic test functions, explicit formulae are derived for the mean and covariance functionals of this fluctuation process. The second paper concerns a family of random matrix ensembles interpolating between the GUE and the Ginibre ensemble of n x n matrices with iid centered complex Gaussian entries. The asymptotic spectral distribution in these models is uniform in an ellipse in the complex plane, which collapses to an interval of the real line as the degree of non-Hermiticity diminishes. Scaling limit theorems are proven for the eigenvalue point process at the rightmost edge of the spectrum, and it is shown that a non-trivial transition occurs between Poisson and Airy point process statistics when the ratio of the axes of the supporting ellipse is of order n -1/3.
Denna avhandling består av två vetenskapliga artiklar som handlar om gränsvärdessatser för slumpmatriser och måttvärda stokastiska processer. De modeller som studeras kan betraktas som generaliseringar av den gaussiska unitära ensembeln (GUE) av hermiteska n x n-matriser H=A+A†, där A är en matris vars element är oberoende, likafördelade, centrerade, komplexa normalfördelade stokastiska variabler. I artikel I betraktas ett system av växelverkande diffunderande partiklar på reella linjen, vissa specialfall av denna modell kan tolkas som egenvärdesdynamiken för matrisvärda Ornstein-Uhlenbeck-processer (Dysons brownska rörelse). Sedan tidigare är det känt att den empiriska måttprocessen konvergerar svagt mot en deterministisk måttvärd funktion och att fluktuationerna runt denna gräns, i lämplig skalning, konvergerer svagt mot en distributionsvärd gaussisk process. För en stor klass av analytiska testfunktioner härleds explicita formler för medelvärdes- och kovariansfunktionalerna för denna fluktuationsprocess. Artikel II behandlar en familj av slumpmatrisensembler som interpolerar mellan GUE och Ginibre-ensembeln, bestående av matriser A som ovan. För denna modell är egenvärdena komplexa och asymptotiskt likformigt fördelade i en ellips i komplexa planet. Skalningsgränsvärdessatser för egenvärdet med maximal realdel och för egenvärdespunktprocessen kring detta visas för ett allmänt val av interpolationsparametern i modellen. Då förhållandet mellan axlarna i den asymptotiska ellipsen är av storleksordning n-1/3 uppträder en övergångsfas mellan Airypunktprocess- och Poissonprocessbeteendena, typiska för GUE respektive Ginibre-ensembeln.
QC 20100705

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Eschmann, Marcel. "Study of bitwise operations on non-scarce attribute based data structures in PostgreSQL." Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-232075.

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This report investigates the viability of bitwise operations on non-scarce attribute based data structures in PostgreSQL. For applications where computation can’t be avoided, it most probably can be optimized. In an attempt of bringing the computation closer to hardware and the underlying data, operations directly on the database system are explored, taking inspiration from the research field of comparative genomics. With the case-study of an online job platform in mind, where possible matchings between candidate and job descriptions are calculated by a matching engine, a binary encoding is proposed and the computational components identified. The ultimate goal was to evaluate the scalability of the bitwise strategy with respect to the current matching engine. Through an iterative approach, this report conducts quantitative experiments on the presented components. Most notably, an implementation of the population count in the form of a C extension was introduced. It was found, that even for large sequence lengths, the operation is highly efficient. Among the chosen algorithms Lookup Table, Hamming Weight, Intrinsic functions and Unrolled Inline Assembly, the 64 bit intrinsic function displayed the best performance. Benchmarks determined, that the proposed bitwise approach is an excellent strategy for the outlined use-case. Despite the tradeoff of additional complexity in the encoding and decoding of data, the speedup is so significant, that the targeted user base of 100000 can easily be managed and allows for the deprecation of caching mechanisms.
Denna rapport undersöker gångbarheten för bitwise-operationer på icke-knappa attributbaserade datastrukturer i PostgreSQL. För applikationer där komputationen inte kan undvikas, kan den högst troligen optimeras. I ett försök att föra beräkningen närmare hårdvaran och den underliggande datan, undersöks operationer direkt på databasen med inspiration från forskningsområdet inom komparativ genomik. Med fallstudien av en online rekryteringsplattform i åtanke, där möjliga matchningar mellan kandidatoch arbetsbeskrivningar beräknas av en matchningsmotor, föreslås en binär kodning och komputationskomponenterna identifieras. Det slutgiltiga målet var att utvärdera skalbarheten hos bitwise-strategin med avseende till den aktuella matchningsmotorn. Genom ett iterativ tillvägagångssätt utför denna rapport kvantitativa experiment på de presenterade komponenterna. Framför allt infördes en implementering av population count i form av ett C-tillägg i databasen. Det visade sig att även för större sekvenslängder är operationen mycket effektiv. Bland de utvalda algoritmerna Lookup Table, Hamming Weight, Intrinsic-funktioner och Unrolled Inline Assembly, visade 64-bitars Intrisicfunktionen den bästa prestandan. Experimenten fastställde att det föreslagna bitwisetillvägagångssättet är en utmärkt strategi för den valda fallstudien. Trots avvägningen med ytterligare komplexitet vid kodning och avkodning av data är hastigheten så signifikant att ett användarantal på 100000 enkelt kan hanteras och möjliggör uteslutning av cache-mekanismer.

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42

Nemoto, Takahiro. "Phenomenological structure for large deviation principle in time-series statistics." 京都大学 (Kyoto University), 2015. http://hdl.handle.net/2433/199092.

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43

Riesch, Christian. "Non-equilibrium dynamics in ordered modulated phases." Doctoral thesis, Universitätsbibliothek Chemnitz, 2015. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-qucosa-172821.

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In der vorliegenden Arbeit wird die Dynamik geordneter modulierter Phasen außerhalb des thermischen Gleichgewichts untersucht. Der Schwerpunkt liegt auf einem zweidimensionalen, streifenbildenden System, genannt Modell B mit Coulomb-Wechselwirkung, welches aus einem geordneten Anfangszustand unter dem Einfluß eines Rauschterms relaxiert. Aus den mittels numerischer Simulationen gewonnenen Daten wird die lokale Orientierung der Streifen extrahiert und deren raum-zeitliche Korrelationsfunktionen berechnet. Wir beobachten eine langsame Dynamik und Alterungseffekte in der Zwei-Zeit-Autokorrelationsfunktion, welche einer Skalenform folgt, die aus kritischen Systemen bekannt ist. Dies geht einher mit dem Wachstum einer räumlichen Korrelationslänge senkrecht zu den Streifen. Zu sehr späten Zeiten klingt die zugehörige räumliche Korrelationsfunktion mit einem Potenzgesetz ab. Weiterhin wird der Einfluß der Systemgröße und verschiedener Seitenverhältnisse auf die Dynamik des Orientierungsfeldes studiert, wobei ein Wachstumsprozeß parallel zur Ausrichtung der Streifen identifiziert wird. Es zeigt sich, daß dieser Prozeß für die Nichtgleichgewichtsdynamik entscheidend ist. Zwei weitere Modelle für modulierte Phasen werden in ähnlicher Weise untersucht. Die Swift-Hohenberg-Gleichung in der Variante mit erhaltenem sowie nicht erhaltenem Ordnungsparameter zeigt ebenfalls Alterungseffekte in der Dynamik der Streifenorientierung. In einem System, welches zweidimensionale hexagonale Muster bildet, werden Alterungseffekte in der Autokorrelationsfunktion der Verschiebung beobachtet. Jedoch sättigt die zugehörige räumliche Korrelationslänge bei einem endlichen Wert, was auf eine Unterbrechung der Alterung hindeutet.

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44

Bergman, Anders. "A Theoretical Study of Magnetism in Nanostructured Materials." Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis : Universitetsbiblioteket [distributör], 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-6763.

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45

Tagwireyi, Paradzayi. "Ant and spider dynamics in complex riverine landscapes of the Scioto River basin, Ohio: implications for riparian ecosystem structure and function." The Ohio State University, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=osu1398983906.

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46

Gritli, Manel. "Protection de l’acier au carbone contre l’entartrage par un traitement à base de polymère non toxique et dopage aux cations cuivre et zinc." Thesis, Sorbonne université, 2019. http://accesdistant.upmc.fr/login?url=http://theses-intra.upmc.fr/modules/resources/download/theses/2019SORUS623.pdf.

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Le phénomène d’entartrage, principalement lié à la précipitation du carbonate de calcium (CaCO3) est très largement rencontré dans les industries et les circuits utilisant de l’eau. Sa présence entraîne des problèmes à la fois techniques et économiques. La prévention et la mise en place de moyens de lutte contre l’entartrage constituent une préoccupation majeure des chercheurs qui s’intéressent à ce phénomène. Ce travail de thèse décrit l’influence des cations métalliques cuivre (II) et zinc (II) sur la précipitation de CaCO3. La première partie met l’accent sur l’effet inhibiteur de ces ions vis-à-vis de l’entartrage, dans des eaux synthétiques de 25 et 50°F. Les investigations sont menées en utilisant la méthode de précipitation contrôlée rapide (PCR) et la microbalance à cristal de quartz avec une surface pré-entartrée (SQCM). Ces mesures permettent de suivre le processus de germination et de croissance du carbonate de calcium en solution et sur la surface métallique pré-entartrée. Les résultats montrent que les ions Zn2+ et Cu2+ jouent un rôle important sur la cinétique de la formation de CaCO3. Ils agissent comme des retardateurs du phénomène d’entartrage. La deuxième partie est dédiée à l’étude du phénomène d’entartrage sur une surface en acier prétraitée par un film hybride organique-inorganique (films à bases de polysiloxanes) déjà testé contre la corrosion, élaboré par le procédé sol–gel. Les méthodes QCM et la chronoampérométrie (CA) ont permis le suivi de la cinétique de précipitation du carbonate de calcium sur la surface recouverte par les polymères synthétisés dopés aux cations cuivre et zinc. L’idée est d’agir directement sur la surface métallique en contact de l’eau sans modifier la composition et la nature de l’eau en question. Les résultats obtenus ont montré que le dopage des cations métalliques améliore l’effet antitartre du film
Scaling phenomenon, mainly related to the precipitation of calcium carbonate (CaCO3), is widely encountered in industry using water. It is necessary to find solutions in order to control scale deposition. This thesis describes the influence of two metallic cations, copper (II) and zinc (II), on the CaCO3 precipitation. The first part focuses on the inhibitory effect of these ions on scaling in synthetic waters of 25 and 50 °F. Investigations are conducted using Fast Controlled Precipitation method (FCP) and Scaling Quartz Crystal Microbalance (SQCM). These measurements make it possible to follow the nucleation and growth processes of calcium carbonate in solution and on the pre-calcareous metallic surface. The results show that Zn2+ and Cu2+ ions play an important role in the kinetics of CaCO3 formation. They act as retarders of the scaling phenomenon. The second part is devoted to the study of the scaling phenomenon on a steel surface pretreated with an organic-inorganic hybrid film (polysiloxane-based films) already tested against corrosion, developed in an original way using the sol–gel process. The QCM and chronoamperometric (CA) methods allowed the monitoring of calcium carbonate precipitation kinetics on the surface covered by the synthesized polymers doped with copper and zinc cations. The idea is to act directly on the metallic surface in contact with the water without modifying the composition and the nature of the water in question. The obtained results show that the doping of the metal cations improves the anti-scaling effect of the film

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47

Kortchemski, Igor. "Conditionnement de grands arbres aléatoires et configurations planes non-croisées." Phd thesis, Université Paris Sud - Paris XI, 2012. http://tel.archives-ouvertes.fr/tel-00818190.

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Les limites d'échelle de grands arbres aléatoires jouent un rôle central dans cette thèse.Nous nous intéressons plus spécifiquement au comportement asymptotique de plusieurs fonctions codant des arbres de Galton-Watson conditionnés. Nous envisageons plusieurs types de conditionnements faisant intervenir différentes quantités telles que le nombre total de sommets ou le nombre total de feuilles, avec des lois de reproductions différentes.Lorsque la loi de reproduction est critique et appartient au domaine d'attraction d'uneloi stable, un phénomène d'universalité se produit : ces arbres ressemblent à un même arbre aléatoire continu, l'arbre de Lévy stable. En revanche, lorsque la criticalité est brisée, la communauté de physique théorique a remarqué que des phénomènes de condensation peuvent survenir, ce qui signifie qu'avec grande probabilité, un sommet de l'arbre a un degré macroscopique comparable à la taille totale de l'arbre. Une partie de cette thèse consiste à mieux comprendre ce phénomène de condensation. Finalement, nous étudions des configurations non croisées aléatoires, obtenues à partir d'un polygône régulier en traçant des diagonales qui ne s'intersectent pas intérieurement, et remarquons qu'elles sont étroitement reliées à des arbres de Galton-Watson conditionnés à avoir un nombre de feuilles fixé. En particulier, ce lien jette un nouveau pont entre les dissections uniformes et les arbres de Galton-Watson, ce qui permet d'obtenir d'intéressantes conséquences de nature combinatoire.

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Mesquita, Julio Carlos Polimeni de. "Caracterização morfoagronômica e diversidade genética em populações F3 de pimenteiras ornamentais (Capsicum annuum L.)." Universidade Federal da Paraíba, 2015. http://tede.biblioteca.ufpb.br:8080/handle/tede/8224.

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Submitted by Katiane Souza (katyane.souza@gmail.com) on 2016-06-05T13:21:28Z No. of bitstreams: 1 arquivogeral.pdf: 2116290 bytes, checksum: 06e1c61195711fc54f91cf9dd76556c0 (MD5)
Made available in DSpace on 2016-06-05T13:21:28Z (GMT). No. of bitstreams: 1 arquivogeral.pdf: 2116290 bytes, checksum: 06e1c61195711fc54f91cf9dd76556c0 (MD5) Previous issue date: 2015-09-03
Capsicum genus presents wide genetic variability and the most used way to determine this variability is through morphological descriptors, essential to obtain information on available diversity, making it possible to better use in breeding programs. Knowledge of this diversity is critical for breeding program of the species one wants to improve, which could be, in the case of pepper plant, cultivar development that are intended for fruit production, for fresh consumption, industries: food of condiments, canned and dyes; pharmaceutical; cosmetics; for use as a rootstock, or more recently as ornamental plant. So the first chapter of this doctoral thesis aimed to characterize and evaluate genetic divergence and heritability of morphoagronomic characteristics in thirteen populations of ornamental pepper plant, being eight populations F3: F21 (P-1), F24 (P-2), F25 (P-3), F27 (P-4), F29 (P-5), F210 (P-6), F211 (P-7) and F231 (P-8), of crossing between the accesses 134 (P-9) and 77.2 (P10), and five additional witnesses: accesses 134 (P9), 77.2 (P10), 10.1 (P11), 10.2 (P-12), and 10.3 (P-13). The P-9 access presents small size, green leaves, white flowers, and cream to red small fruits. The P-10 access is composed of high-sized plants with vein-like leaves, purple flowers and small fruits and lilac to red fruits. P-11, P-12, and P-13 accesses show plants with very similar size characteristics, large and showy fruits, only differing in the color of ripe fruit P-11 (yellow), P-12 (red), and P-13 (orange). The work was conducted in a greenhouse. Fifty plants of each F3 population and ten of each additional witnesses were distributed in a completely randomized experimental design with two factors: Population and Years. Sixteen morphological descriptors were evaluated, being six of plant and ten of fruit. Variance analysis was performed with the data of the five witnesses and used residual mean squared error to conduct the means comparison test. Genotypes were grouped according to Scott-Knott criteria (p ≤ 0.05). The interaction was significant for all traits, except for the height of the first fork and number of seeds per fruit. The heritability ranged from 91.18% (stem diameter) to 99.97% (greater fruit diameter), for the first year of evaluation, and 85.75% (dry matter content) to 99.65% (higher fruit diameter), for the second year. The relation between genetic variation coefficient and environmental variation coefficient presented values higher than 1 for all traits, except for stem diameter, fruit length / diameter ratio and dry matter content. P3 population was the one with the lowest average for plant height and canopy diameter, thus, being the most recommended for selection of ornamental size. In the second chapter, the objective was to evaluate the genetic divergence between thirteen populations of ornamental pepper plants, using multivariate techniques and determine which morphological characteristics contributed more for genetic divergence. Genetic divergence between populations of ornamental pepper plants was determined by clustering analysis and canonical variables. Multivariate analysis revealed that there is interaction between the studied factors (p <0.01). There was agreement between the multivariate techniques used. Fruit characteristics were those that most contributed for genetic divergence, separating the populations P11, P12 and P13 from other populations. These results were repeated in the two years of evaluation. The third chapter aimed to characterize and estimate genetic divergence within pre-established groups of populations F3 of ornamental pepper plants. Eight F3 populations were evaluated in a completely randomized design with two factors (Populations and Years). Quantitative and qualitative descriptors were used. Dissimilarity matrices were estimated between genotypes within the populations, using Gower dissimilarity coefficient. Ggenotypic divergence explained by dissimilarity matrices were analyzed via non-metric multidimensional scaling (nMDS). Internal consistency presented by populations P4, P6, P7, P5, and P8, indicates that the genotypes of these populations present capability for use in future ornamental pepper plant breeding programs. On the other hand, populations P1, P2, and P3 presented the highest visual dispersion, allowing selection, aiming advancement of future generations.
O gênero Capsicum apresenta ampla variabilidade genética e a maneira mais utilizada de determinar essa variabilidade é através dos descritores morfológicos, essenciais para se obter informações sobre a diversidade disponível, possibilitando sua melhor utilização em programas de melhoramento. O conhecimento dessa diversidade é fundamental para o programa de melhoramento genético da espécie que se deseja melhorar, a qual poderá ser, no caso de pimenteiras, o desenvolvimento de cultivares que se destinem a produção de frutos, para consumo in natura, indústrias: alimentícias de condimentos, conservas e corantes; farmacêutica; cosmética; para serem utilizadas como porta-enxerto ou, mais recentemente, como planta ornamental. Assim, o primeiro capítulo desta tese de doutoramento, teve como objetivo caracterizar e avaliar a divergência genética e a herdabilidade das características morfoagronômicas em treze populações de pimenteiras ornamentais, sendo oito populações F3: F21 (P-1), F24 (P-2), F25 (P-3), F27 (P-4), F29 (P-5), F210 (P-6), F211 (P-7) e F231 (P-8), originárias do cruzamento entre os acessos 134 (P-9) e 77.2 (P10), e cinco testemunhas adicionais os acessos 134 (P9), 77.2 (P10), 10.1 (P11), 10.2 (P-12) e 10.3 (P-13). O acesso P-9 apresenta porte baixo, folhas verdes, flores brancas frutos pequenos de coloração creme para vermelho. O acesso P-10 são plantas de porte alto com folhas jaspeadas, flores lilás e frutos pequenos e coloração de lilás para vermelho. Já os acessos P-11, P-12 e P-13 plantas com características de porte muito similares, frutos grandes e vistosos diferindo apenas na coloração do fruto maduro P-11(amarelo), P-12 (vermelho) e P-13 (laranja). O trabalho foi conduzido em casa de vegetação. Cinquenta plantas de cada população F3 e dez de cada testemunha adicional foram distribuídas em delineamento experimental inteiramente casualizado com dois fatores: Populações e Anos. Foram avaliados 16 descritores morfológicos, sendo seis referentes a planta e dez ao fruto. A análise de variância foi realizada com os dados das cinco testemunhas e utilizou-se o quadrado médio do resíduo para se realizar o teste de comparação de médias. Os genótipos foram agrupados de acordo com os critérios de Scott-Knott (P≤0,05). A interação foi significativa para todas as características, exceto para a altura da primeira bifurcação e número de sementes por fruto. A herdabilidade variou de 91,18% (diâmetro do caule) a 99,97% (maior diâmetro do fruto), para o primeiro ano de avaliação, e 85,75% (teor de matéria seca) a 99,65% (maior diâmetro do fruto), para o segundo ano. A relação entre o coeficiente de variação genética e o coeficiente de variação ambiental apresentou valores superiores a 1 para todas as características, com exceção para diâmetro do caule, relação comprimento /diâmetro do fruto e teor de matéria seca. A população P3 foi a que apresentou as menores médias para a altura da planta e diâmetro da copa, sendo consequentemente a mais recomendada para seleção dentro visando porte ornamental. No segundo capítulo, o objetivo foi avaliar a divergência genética entre treze populações de pimenteiras ornamentais, usando técnicas multivariadas, e determinar quais as características morfológicas que contribuíram mais para a divergência genética. A divergência genética entre as populações de pimenteiras ornamentais foi determinada por análise de agrupamento e de variáveis canônicas. A análise multivariada revelou que existe interação entre os fatores estudados (p < 0,01). Observou-se concordância entre as técnicas multivariadas utilizadas. As características de fruto foram as que mais contribuíram para a divergência genética, separando as populações P11, P12 e P13 das demais populações. Esses resultados se repetiram nos dois anos de avaliação. O terceiro capítulo, teve como objetivos caracterizar e estimar a divergência genética dentro de grupos pré-estabelecidos de populações F3 de pimenteiras ornamentais. Oito populações F3 foram avaliadas, em delineamento inteiramente casualizado, com dois fatores (Populações e Anos). Foram utilizados descritores quantitativos e qualitativos. Foram estimadas matrizes de dissimilaridade entre genótipos dentro das populações utilizando o coeficiente de dissimilaridade de Gower. A divergência genotípica, explicada pelas matrizes de dissimilaridade, foram analisadas via escalonamento multidimensional não-métrico (nMDS). A uniformidade interna apresentada pelas populações P4, P6, P7, P5 e P8, é indicativo de que os genótipos destas populações apresentam aptidão para serem utilizados em futuros programas de melhoramento de pimenteiras ornamentais. Por outro lado, as populações P1, P2 e P3 apresentaram a maior dispersão visual, possibilitando seleção, visando avanço de gerações futuras.

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49

Ochoa-Lozano, Diana. "Neogene Palynology of the Gray Fossil Site, Tennessee, USA: Floristic Implications." Digital Commons @ East Tennessee State University, 2011. https://dc.etsu.edu/etd/2248.

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In order to understand Mio-Pliocene floristic characteristics of the southern Appalachian Mountains, 47 palynological samples from six different testing-pits across the Gray Fossil Site (GFS) were analyzed. The site exhibits a low pollen yield resulting from basic pH levels, drought, and fire events occurring during deposition. The palynofloral assemblage has a low to moderate diversity, and it is largely dominated by Quercus-Carya-Pinus (~90% of the palynoflora). The reported presence of Pterocarya grains supports a Late Neogene age for the lacustrine sediments. Comparison with modern pollen-based floras suggests that: (1) the Mio-Pliocene Oak-Hickory-Pine association varied in structure between a woodland to woodland/savanna, depending on the intensity and frequency of drought, fire events and herbivory, (2) pits show different structure of the co-dominant genera, which indicate alternating composition of the vegetation, and (3) in term of modern vegetation, the GFS flora corresponds well with the Mesophytic Forest region.

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50

RASOLOARIJAONA, MAMY NIRINA. "Non-linearites de la loi de darcy : etudes theorique, numerique et experimentale." Grenoble 1, 1993. http://www.theses.fr/1993GRE10124.

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Nous etudions la filtration en milieu poreux de fluides newtoniens en utilisant la theorie d'homogeneisation des structures periodiques. Dans un premier temps nous rappelons les resultats obtenus grace a la methode dans les cas de l'ecoulement stationnaire de fluides incompressibles ou compressibles, et de l'acoustique de fluides incompressibles. Dans le premier cas, la filtration est decrite par la loi de darcy, la compressibilite etant prise en compte dans le bilan de masse. Dans le second cas, la loi macroscopique est une loi de darcy generalisee: le tenseur de permeabilite est a valeur complexe et depend de la frequence. Nous etendons ensuite notre etude a la recherche d'une correction faiblement non lineaire a la loi de darcy, le nombre de reynolds re microscopique etant suppose petit. L'ecoulement est suppose stationnaire et le fluide incompressible. Le nombre de reynolds microscopique est pris re=0(). En appliquant les resultats aux filtrations unidirectionnelles, la loi macroscopique est une loi cubique sans terme quadratique. On retrouve le meme terme cubique auquel est adjoint un terme du type (v. Grad)v dans le cas d'un milieu isotrope et homogene. Lorsque re0(), le terme cubique n'apparait pas et lorsque 0()re1, on obtient le terme cubique seul. Finalement, nous effectuons une etude experimentale ainsi qu'un calcul numerique sur un modele monodimensionnel. Les deux etudes portent sur un nombre de reynolds local allant de 0 a 150. Il existe une bonne correspondance entre les resultats numeriques et experimentaux. Ces resultats confirment la loi cubique

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