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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
431

Translation of Fixed Collocations and Idioms / Fiksuotų kolokacijų ir idiomų vertimas

Stočkūnaitė, Milda 13 June 2013 (has links)
The object of the study is the structure and semantics of fixed collocations and idioms in the English language and their Lithuanian equivalents. The aim of the work is to research how English fixed collocations and idioms are translated into Lithuanian and what stylistic and semantic changes they undergo. The main research methods applied in the research are descriptive theoretical literary analysis, contrastive method and statistical method.In theoretical part the concepts of fixed collocation and idiom are discussed. Further consideration is focused on the classification of previously mentioned idiomatic expressions. Fixed collocations and idioms are classified regarding to what they mean and what they refer to. Translation strategies and the difficulties when translating the idiomatic expressions are discussed. The practical part is divided into three parts which examine fully equivalent, semantically similar, formally modified and functionally equivalent fixed collocations and idioms. The selected examples prove that the majority of idioms undergo semantic, stylistic or structural changes in the process of translating them from one language into the other. Though there are some English idioms that have equivalents in Lithuanian, in the majority of cases only few or none of the elements coincide. / Bakalauro baigiamojo darbo objektas yra fiksuotų kolokacijų ir idiomų struktūra bei semantika anglų kalboje ir jų lietuviškuose atitikmenyse. Darbo tikslas - ištyrinėti kaip angliškos fiksuotos kolokacijos bei idiomos išverčiamos į Lietuvių kalbą bei kaip pasikeičia jų stilistika ir semantika. Pagrindiniai tyrimo metodai yra šie: aprašomoji teorinė literatūros analizė, gretinamasis metodas, statistinis metodas. Teorinėje dalyje nagrinėjamos fiksuotos kolokacijos ir idiomos sąvokos. Toliau dėmesys skiriamas jau minėtų idiomatinių išsireiškimų klasifikacijai. Fiksuotos kolokacijos ir idiomos sugrupuotos pagal reikšmę bei tą, ką jos nurodo. Aptariamos vertimo strategijos bei idiomatinių išsireiškimų vertimų sunkumai. Praktinis tyrimas suskirstytas į tris dalis, kurios tiria visiškai ekvivalentiškas, panašias semantiškai, bet pakeista forma ir praktiškai ekvivalentiškas fiksuotas kolokacijas ir idiomas. Pasirinkti pavyzdžiai įrodo, kad daugumos idiomų semantika, stilistika ir struktūra pasikeičia jas verčiant iš vienos kalbos į kitą. Nors ir yra angliškų idiomų, kurios turi atitikmenis Lietuvių kalboje, daugeliu atvejų sutampa tik keli arba nei vienas žodis.
432

ECG Noise Filtering Using Online Model-Based Bayesian Filtering Techniques

Su, Aron Wei-Hsiang January 2013 (has links)
The electrocardiogram (ECG) is a time-varying electrical signal that interprets the electrical activity of the heart. It is obtained by a non-invasive technique known as surface electromyography (EMG), used widely in hospitals. There are many clinical contexts in which ECGs are used, such as medical diagnosis, physiological therapy and arrhythmia monitoring. In medical diagnosis, medical conditions are interpreted by examining information and features in ECGs. Physiological therapy involves the control of some aspect of the physiological effort of a patient, such as the use of a pacemaker to regulate the beating of the heart. Moreover, arrhythmia monitoring involves observing and detecting life-threatening conditions, such as myocardial infarction or heart attacks, in a patient. ECG signals are usually corrupted with various types of unwanted interference such as muscle artifacts, electrode artifacts, power line noise and respiration interference, and are distorted in such a way that it can be difficult to perform medical diagnosis, physiological therapy or arrhythmia monitoring. Consequently signal processing on ECGs is required to remove noise and interference signals for successful clinical applications. Existing signal processing techniques can remove some of the noise in an ECG signal, but are typically inadequate for extraction of the weak ECG components contaminated with background noise and for retention of various subtle features in the ECG. For example, the noise from the EMG usually overlaps the fundamental ECG cardiac components in the frequency domain, in the range of 0.01 Hz to 100 Hz. Simple filters are inadequate to remove noise which overlaps with ECG cardiac components. Sameni et al. have proposed a Bayesian filtering framework to resolve these problems, and this gives results which are clearly superior to the results obtained from application of conventional signal processing methods to ECG. However, a drawback of this Bayesian filtering framework is that it must run offline, and this of course is not desirable for clinical applications such as arrhythmia monitoring and physiological therapy, both of which re- quire online operation in near real-time. To resolve this problem, in this thesis we propose a dynamical model which permits the Bayesian filtering framework to function online. The framework with the proposed dynamical model has less than 4% loss in performance compared to the previous (offline) version of the framework. The proposed dynamical model is based on theory from fixed-lag smoothing.
433

Efficient Computation and Application of Maximum Agreement Forests

Whidden, Chris 29 July 2013 (has links)
Rampant lateral gene transfer (LGT) among prokaryotes, hybridization in plants and other reticulate evolutionary processes invalidate typical phylogenetic tree models by violating the assumption that organisms only inherit genetic information from a single parent species. Comparing the different evolutionary histories of multiple genes is necessary to identify and assess these processes. In this work I develop efficient approximation and fixed-parameter algorithms for computing rooted maximum agreement forests (MAFs) and maximum acyclic agreement forests (MAAFs) of pairs of phylogenetic trees. Their sizes correspond to the subtree-prune-and-regraft (SPR) distance and the hybridization number of these pairs of trees, which are important measures of the dissimilarity of phylogenies used in studying reticulate evolution. Although these MAFs and MAAFs are NP-hard to compute, my fixed-parameter algorithms are practical because they scale exponentially with the computed distance rather than the size of the trees. I contribute efficient fixed-parameter algorithms for computing MAFs and MAAFs of two binary rooted trees and give the first efficient fixed-parameter and approximation algorithms for computing MAFs of two multifurcating rooted trees. My open-source implementation of the MAF algorithms is orders of magnitude faster than previous approaches, reducing the time required to compute SPR distances of 46 between trees of 144 species to fractions of a second whereas previous approaches required hours to compute SPR distances of 25. These fast MAF-based distance metrics enable the construction of supertrees to reconcile a collection of gene trees and rapid inference of LGT. Simulations demonstrate that supertrees minimizing the SPR distance are more accurate than other supertree methods under plausible rates of LGT. I constructed an SPR supertree from a phylogenomic dataset of 40,631 gene trees covering 244 genomes from several major bacterial phyla and inferred "highways" of gene transfer between these bacterial classes and genera; a small number of these highways connect distantly related genera and can highlight specific genes implicated in long-distance LGT. These fast MAF algorithms are thus practical and enable new analyses of reticulate evolution.
434

Characterization of Abuse Properties of the Anesthetic Propofol Using the Self-administration Paradigm in Rats

Baghai Wadji, Fariba 21 November 2013 (has links)
Propofol is a widely in use anesthetic drug. Propofol’s abuse liability has been supported by many case reports and a few animal studies. However, propofol’s reinforcing properties have not yet been investigated in-depth. In this study, multiple aspects of propofol’s abuse-related behaviour were investigated using the drug self-administration model in rats. METHODS: Rats were subjected to propofol self-administration under a fixed ratio 1 (FR1) schedule and different aspects of propofol self-administration behaviour including acquisition, maintenance of the behaviour under a higher ratio schedule, extinction and reinstatement were investigated. RESULTS: Rats acquired propofol self-administration under a FR1 schedule. The acquired behaviour was maintained under a FR2 schedule, showed a modest variation over a range of doses, and was extinguished upon substitution of vehicle for propofol, showing no reinstatement using a range of priming doses of propofol. CONCLUSION: Propofol has abuse potential showing modest reinforcing properties under our experimental conditions.
435

Panel Data Econometric Models: Theory and Application

Gao, Yichen 16 December 2013 (has links)
This dissertation contains two essays studying panel data econometric models. First, we consider the problem of estimating a nonparametric panel data models with fixed effects. We propose using the profile least squares method to concentrate out the fixed effects and then estimate the unknown function by the kernel method. We show that our proposed estimator is consistent and has an asymptotically normal distribution. Monte Carlo simulations show that our proposed estimator performs well compared with several existing estimators. Second, we study the effects of Hong Kong’s fixed exchange rate against U.S. dollar using a novel panel data method. After the 1997 Asian Financial Crisis, many of the Asia countries adopted flexible exchange rate policies while Hong Kong still keeps its fixed exchange rate. By comparing Hong Kong versus its major trading partners, we show that if, like other Asian countries, Hong Kong had adopted a float exchange rate policy in October 1998, Hong Kong’s (counterfactual) total value of exports would increase by 14.65 %. Similarly, Hong Kong’s total value of imports would increase about 31%. We conclude that Hong Kong dollar is overvalued by 9.34% due to its fixed exchange rate policy.
436

Characterization of Abuse Properties of the Anesthetic Propofol Using the Self-administration Paradigm in Rats

Baghai Wadji, Fariba 21 November 2013 (has links)
Propofol is a widely in use anesthetic drug. Propofol’s abuse liability has been supported by many case reports and a few animal studies. However, propofol’s reinforcing properties have not yet been investigated in-depth. In this study, multiple aspects of propofol’s abuse-related behaviour were investigated using the drug self-administration model in rats. METHODS: Rats were subjected to propofol self-administration under a fixed ratio 1 (FR1) schedule and different aspects of propofol self-administration behaviour including acquisition, maintenance of the behaviour under a higher ratio schedule, extinction and reinstatement were investigated. RESULTS: Rats acquired propofol self-administration under a FR1 schedule. The acquired behaviour was maintained under a FR2 schedule, showed a modest variation over a range of doses, and was extinguished upon substitution of vehicle for propofol, showing no reinstatement using a range of priming doses of propofol. CONCLUSION: Propofol has abuse potential showing modest reinforcing properties under our experimental conditions.
437

ANALYTICAL METHODS FOR TRANSPORT EQUATIONS IN SIMILARITY FORM

Tiwari, Abhishek 01 January 2007 (has links)
We present a novel approach for deriving analytical solutions to transport equations expressedin similarity variables. We apply a fixed-point iteration procedure to these transformedequations by formally solving for the highest derivative term and then integrating to obtainan expression for the solution in terms of a previous estimate. We are able to analyticallyobtain the Lipschitz condition for this iteration procedure and, from this (via requirements forconvergence given by the contraction mapping principle), deduce a range of values for the outerlimit of the solution domain, for which the fixed-point iteration is guaranteed to converge.
438

PAY-AS-YOU-GO ELECTRICITY: THE IMPACT OF PREPAY PROGRAMS ON ELECTRICITY CONSUMPTION

Martin, William M 01 January 2014 (has links)
Prepay or pay-as-you-go programs are an increasingly popular type of rate plan offered by electric utilities. Under these plans, ratepayers must keep a positive balance at all times to avoid being automatically disconnected, they are charged daily for their usage, and they are provided with a means to monitor their consumption. One of the suggested benefits of these plans is that they allow electricity consumers to better manage their usage. Using household level monthly usage data from customers enrolled in prepay programs at two Kentucky rural electric cooperatives, we investigate whether there is a change in consumption after these customers enrolled in the program. To address this question, we employ a fixed-effects model. The results of our model indicate that prepay customers reduce their consumption by an average of 11% after enrolling in the program. We also find that this response is larger during periods of high or low temperatures than during mild weather. Furthermore, we find evidence that the prepayment effect diminishes over the length of time that a customer is enrolled in the program.
439

Meta aircraft flight dynamics and controls

Montalvo, Carlos 22 May 2014 (has links)
The field of mobile robotic systems has become a rich area of research and design. These systems can navigate difficult terrain using multiple actuators with conventional ambulation, by hopping, jumping, or for aerial vehicles, using flapping wings, propellers, or engines to maintain aerial flight. Unmanned Aerial Systems(UAS) have been used extensively in both military and civilian applications such as reconnaissance or search and rescue missions. For air vehicles, range and endurance is a crucial design parameter as it governs which missions can be performed by a particular vehicle. In addition, when considering the presence of external disturbances such as atmospheric winds, these missions can be even more challenging. Meta aircraft technologies is one area of research that can increase range and endurance by taking advantage of an increase in L/D. A meta aircraft is an aircraft composed of smaller individual aircraft connected together through a similar connection mechanism that can potentially transfer power, loads, or information. This dissertation examines meta aircraft flight dynamics and controls for a variety of different configurations. First, the dynamics of meta aircraft systems are explored with a focus on the changes in fundamental aircraft modes and flexible modes of the system. Specifically, when aircraft are connected, the fundamental modes change, can become overdamped or even unstable. In addition, connected aircraft exhibit complex flexible modes and mode shapes that change based on the parameters of the connection joint and the number of connected aircraft. Second, the connection dynamics are explored for meta aircraft where the vehicles are connected wing tip to wing tip using passive magnets with a particular focus on modeling the connection event between aircraft in a practical environment. It is found that a multi-stage connection control law with position and velocity feedback from GPS and connection point image feedback from a camera yields adequate connection performance in the presence of realistic sensor errors and atmospheric winds. Furthermore, atmosphericwinds with low frequency gusts at the intensity normally found in a realistic environment pose the most significant threat to the success of connection. The frequency content of the atmospheric disturbance is an important variable to determine success of connection. Finally, the geometry of magnets that create the connection force field can alter connection rates. Finally, the performance of a generic meta aircraft system are explored. Using a simplified rigid body model to approximate any meta aircraft configuration, adequate connection is achieved in the presence of realistic winds. Using this controller overall performance is studied. In winds, there is an overall decrease in outer loop performance for meta aircraft. However, inner loop performance increases for meta aircraft. In addition, the aerodynamic benefit of different configurations are investigated. Wing to wing tip connected flight provides the most benefit in terms of average increased Lift to Drag ratio while tip to tail configurations drop the Lift to Drag ratio as trailing aircraft fly in the downwash of the leading aircraft.
440

Remittances and Development : Empirical evidence from 99 developing countries

Ångman, Josefin, Larsson, Pernilla January 2014 (has links)
Several studies have examined the effect of remittances on economic growth,poverty, education, and governance, among other factors, in developing countrieswith inconclusive results. Using annual panel data of 99 developing countries invarious empirical models, this study aim to answer the question how remittances affect a broader aspect of development using the Human Development Index asdependent variable. The findings indicate that there is a positive relationship between remittances and the level of human development in developing countries.

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