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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.
231

CHARACTERISTICS OF SEVENTH-GRADE MIDDLE SCHOOL STUDENTS WHO ATTENDED A CONTINUATION HIGH SCHOOL

Kit, Rae Lynn 01 April 2019 (has links)
This study explored pre-existing quantitative data for 55 students when they were in the seventh grade who eventually attended a continuation high school years later. There were 101 students at a particular continuation high school, and this research explored pre-existing data looking solely at the students who were in the same district while they were in seventh grade. Attendance and grades from the pre-existing data in the district’s software system were analyzed using a descriptive methodology followed by a cluster analysis through SPSS. Attendance findings for the 55 students revealed that nine students (16%) were absent with a frequency of 10 or more days in each semester. Reasons given for some absences were bereavement for four students (7%) and suspensions for 10 students (18%). Eight out of these 10 students (80%) declined in their grades from the first semester to the second semester. Overall, 33 students (60%) declined in their grades from the first semester to the second semester regardless. Findings related to grades looked at the number of Fs over the two semesters of the seventh-grade school year and at the number of Fs earned in each course. Forty-four students (80%) earned at least one F either semester. Language Arts was the highest failed academic class second semester, with 32 out of 55 students (58%), and Computer Applications was the highest failed elective class for 5 out of 9 students (56%) who took this class second semester. Other findings related to grades were that 0 students (0%) failed only the elective, and only 2 students (4%) failed Physical Education. Additional findings through cluster analysis revealed a connection between failing an elective in combination with failing Language Arts: 81.8% first semester (9 out of 11 students) and 83.3% second semester (5 out of 6 students). Using a cross-tabulation, the highest pattern between the two semesters was for 10 students of the overall 55 (18%) with no Fs both semesters, and the second-highest pattern was for 6 students (11%) with no Fs first semester and 1 F second semester.
232

兩段迴歸結合蒙地卡羅模擬對可轉債定價之研究 / Pricing Convertible Bonds by Piecewise Regression and Monte Carlo Simulation

董恆元, Tung, Heng Yuan Unknown Date (has links)
可轉換公司債兼具了選擇權以及債券的性質,價值又會受到股價之影響,以傳統的方法定價十分不易。由於蒙地卡羅模擬能解決定價問題上狀態變數或許為多維度及路徑相依的問題,Kind 與Wilde 在2004 年提出以蒙地卡羅模擬對可轉債定價,且以最小平方迴歸法估計繼續持有價值,並在僅考慮轉換及還本兩種選擇權及沒有違約風險之下,以數值範例呈現單一迴歸模式無法適當估計繼續持有價值。然而,他們並未進行實證。本研究乃以民國99 年台灣發行的可轉債為研究對象,除考慮發行時的合約條件外,另加上信用評等的考量以將違約機率透過現金流量套入定價過程中,並分別以兩段迴歸及單一迴歸估計繼續持有價值以結合蒙地卡羅模擬,實證結果顯示就可轉債之起始定價的偏差比而言,兩段迴歸得到的結果優於單一迴歸。惟在兩段迴歸之下,超過八成的可轉債其模擬價格依然高於市場價格。實證結果也顯示價性(moneyness)及擔保狀況與定價的偏差有關。 / Convertible bonds (CBs) possess features of both bonds and options, and their prices are affected by the underlying stocks, which make the pricing problem an uneasy task for traditional methods. Since Monte Carlo simulation can handle the problems of path-dependence and multivariate dimensions faced by pricing, Kind and Wilde (2004) suggested to price CBs via least-squares Monte Carlo simulations (LSM), which estimate the continuation values by least squares regression. They also demonstrated that a single regression line could not appropriately estimate the continuation value even only conversion and redemption were allowed and the CB was free of default. So the idea of piecewise regression was recommended to improve the estimation process. However, they didn’t apply piecewise regression to real data. Therefore, piecewise regression together with Monte Carlo simulation were employed to investigate the pricing issue of Taiwan’s CBs. CBs issued on 2010 were selected, besides reviewing the contents of CB’s contracts, default risks based on credit ratings were taken into account to evaluate the discounted cash flows in the pricing procedure. Comparing the estimated model prices of LSM with initial selling prices, the mispricing rates of single regression model and piecewise regression model were obtained for further analysis. Result shows that the modified piecewise regression method performs better in mispricing rate. However, similar to previous findings, 80% of the estimated model prices based on piecewise regressions are still higher than market prices. It also shows that moneyness and guaranteed condition will relate to mispricing rate.
233

Fredens ö i krigets hav : En pressundersökning av Växjö tidningars ledare om andra världskrigets konflikter i Norden / The Island of Peace in the Sea of War : A newspaper study of Växjö city’s newspaper editorials regarding the conflicts of the Second World War in the Nordic countries

Gustafsson, Joel, Söderqvist, Niclas January 2015 (has links)
ABSTRACT Gustafsson, J. & Söderqvist, N., “’The Island of Peace in the Sea of War’ A newspaper study of Växjö city’s newspaper editorials regarding the conflicts of the Second World War in the Nordic countries”, Linnaeus University.   A qualitative textual analysis delving into three local newspapers from Växjö city is in many ways the essence of this study. The main purpose of this study is to examine three key conflicts, the Winter War, Operation Weserübung and the Continuation War. Each conflict has been assessed in relation to the opinions advocated in the editorials of the three politically diverse newspapers. The theoretical basis for this study is founded on similar analysis made by Nybom, Johansson and Åmark who all have contributed to the content of this particular essay. Most of all, Nyboms categorization of the so-called realism and idealism have helped us in understanding the motives and plans of action concerning the nations involved in the selected conflicts. There are several interesting conclusions in this study, in particular the newspapers’ view on main antagonists such as the Soviet Union and Nazi Germany, as well as the Allies.
234

Etude du prolongement méromorphe de fonctions zëta spectrales grâce à la géométrie non commutative / Meromorphic continuation of spectral zeta functions approach to noncommutative geometry

Gautier-Baudhuit, Franck 10 November 2017 (has links)
Cette thèse s'intéresse à des familles de fonctions zêta spectrales (séries de Dirichlet) qui peuvent être associées à certaines algèbres d'opérateurs sur des espaces de Hilbert. Dans ce mémoire, la principale question étudiée sur ces fonctions zêta est l'existence d'un prolongement méromorphe à partir d'un demi-plan ouvert du plan complexe au plan complexe tout entier. Généralisant une idée de Nigel Higson, on propose dans la partie I, une méthode pour prouver l'existence de ce prolongement méromorphe pour certains fonction zêta spectrales. Cette méthode s’effectue dans le cadre d'algèbres d'opérateurs différentiels généralisés et elle s'appuie sur une suite de réduction. Le théorème principal donne, sous certaines conditions, l'existence d'un prolongement méromorphe, une localisation des pôles dans les supports de suites arithmétiques et une borne supérieure pour l'ordre de ces pôles. Dans la partie II, on reformule la méthode de la partie I dans le contexte et avec le vocabulaire des triplets spectraux de Connes et Moscovici. Dans la troisième partie, on donne une application pour des fonctions zêta associées à des opérateurs de type Laplace sur des variétés lisses, compactes et sans bord. Cet exemple a été initialement traité par Nigel Higson avec cette approche en 2006. Une deuxième application traite de fonctions zêta associées au tore non commutatif. Dans la partie IV, on utilise le calcul pseudodifférentiel associé à des algèbres de Lie nilpotentes et développé par Dominique Manchon, pour construire de nouveaux triplets spectraux. Dans la partie V se trouve la principale application de la méthode exposée dans ce mémoire. On prouve l'existence du prolongement méromorphe pour des fonctions zêta provenant de représentations de Kirillov d'une classe d'algèbre de Lie nilpotentes. / The thesis is about a families of zeta functions (Dirichlet series) that may be associated to certain algebras of Hilbert space operators. In this thesis, the main question in studying these zeta functions is to establish their meromorphic continuation from a half-plane in the complex plane to the full plane.Following an idea of Nigel Higson, we develop, in part I, a method for proving the existence of a meromorphic continuation for some spectral zeta functions. The method is based on algebras of generalized differential operators. The more important tool is the reduction sequence. The main theorem states, under some conditions, the existence of a meromorphic continuation, a localization of the poles in supports of arithmetic sequences and an upper bound of their order. A formulation of the method into the framework of Connes and Moscovici, the regular spectral triples, setting in part II. In the third part, we give an application for zeta functions associate to a Laplace-type operator on a smooth, closed manifold. This example was initially treated in this way by Nigel Higson in 2006. We give another application for zeta functions associate to the noncommutative torus. In part IV, using the work of Dominique Manchon on algebras of pseudodifferential operators associated to unitary representations of nilpotent Lie group, we construct new spectral triples. In part V, set the main application of the method. We applicate the reduction method for some algebras of generalized differential operators, arising from a Kirillov representation of a class of nilpotent Lie algebras.
235

Theoretical methods for the electronic structure and magnetism of strongly correlated materials

Locht, Inka L. M. January 2017 (has links)
In this work we study the interesting physics of the rare earths, and the microscopic state after ultrafast magnetization dynamics in iron. Moreover, this work covers the development, examination and application of several methods used in solid state physics. The first and the last part are related to strongly correlated electrons. The second part is related to the field of ultrafast magnetization dynamics. In the first part we apply density functional theory plus dynamical mean field theory within the Hubbard I approximation to describe the interesting physics of the rare-earth metals. These elements are characterized by the localized nature of the 4f electrons and the itinerant character of the other valence electrons. We calculate a wide range of properties of the rare-earth metals and find a good correspondence with experimental data. We argue that this theory can be the basis of future investigations addressing rare-earth based materials in general. In the second part of this thesis we develop a model, based on statistical arguments, to predict the microscopic state after ultrafast magnetization dynamics in iron. We predict that the microscopic state after ultrafast demagnetization is qualitatively different from the state after ultrafast increase of magnetization. This prediction is supported by previously published spectra obtained in magneto-optical experiments. Our model makes it possible to compare the measured data to results that are calculated from microscopic properties. We also investigate the relation between the magnetic asymmetry and the magnetization. In the last part of this work we examine several methods of analytic continuation that are used in many-body physics to obtain physical quantities on real energies from either imaginary time or Matsubara frequency data. In particular, we improve the Padé approximant method of analytic continuation. We compare the reliability and performance of this and other methods for both one and two-particle Green's functions. We also investigate the advantages of implementing a method of analytic continuation based on stochastic sampling on a graphics processing unit (GPU).
236

Multistability in microbeams: Numerical simulations and experiments in capacitive switches and resonant atomic force microscopy systems

Devin M Kalafut (11013732) 23 July 2021 (has links)
Microelectromechanical systems (MEMS) depend on mechanical deformation to sense their environment, enhance electrical circuitry, or store data. Nonlinear forces arising from multiphysics phenomena at the micro- and nanoscale -- van der Waals forces, electrostatic fields, dielectric charging, capillary forces, surface roughness, asperity interactions -- lead to challenging problems for analysis, simulation, and measurement of the deforming device elements. Herein, a foundation for the study of mechanical deformation is provided through computational and experimental studies of MEMS microcantilever capacitive switches. Numerical techniques are built to capture deformation equilibria expediently. A compact analytical model is developed from principle multiphysics governing operation. Experimental measurements support the phenomena predicted by the analytical model, and finite element method (FEM) simulations confirm device-specific performance. Altogether, the static multistability and quasistatic performance of the electrostatically-actuated switches are confirmed across analysis, simulation, and experimentation. <p><br></p> <p>The nonlinear multiphysics forces present in the devices are critical to the switching behavior exploited for novel applications, but are also a culprit in a common failure mode when the attractive forces overcome the restorative and repulsive forces to result in two elements sticking together. Quasistatic operation is functional for switching between multistable states during normal conditions, but is insufficient under such stiction-failure. Exploration of dynamic methods for stiction release is often the only option for many system configurations. But how and when is release achieved? To investigate the fundamental mechanism of dynamic release, an atomic force microscopy (AFM) system -- a microcantilever with a motion-controlled base and a single-asperity probe tip, measured and actuated via lasers -- is configured to replicate elements of a stiction-failed MEMS device. Through this surrogate, observable dynamic signatures of microcantilever deflection indicate the onset of detachment between the probe and a sample.</p>
237

Invloed van samelewingsveranderinge op verhoudinge binne die stedelike gesin : 'n sosio-opvoedkundige verkenning / The influence of changing societal phenomena on urban families : a socio-educational analysis

Scholtz, Renée 01 1900 (has links)
Die 21ste eeuse postmodeme samelewing word gekenmerk deur dinamiese veranderinge op aile gebiede wat die kwaliteit van die gesinslewe en opvoedingsbegeleiding binne gesinne bepaaL Hierdie studie poog om aan die hand van 'n omvangryke literatuurstudie en kwalitatiewe ondersoek, die aard, omvang en invloed van sodanige samelewingsverskynsels op verhoudingstigting- en onderhouding en die kwaliteit van opvoedingsbegeleiding in eietydse stadsgesinne te bepaal. Bevindinge toon dat sommige gesinne, as gevolg van hierdie veranderinge, uiters kwesbaar is, dat verhoudinge ontaard en opvoedingsbegeleiding ontoereikend voltrek. Die verval van norme en waardes is veral verswarend vir opvoeding en volwassewordingshulp. Ouers en kinders moet onder verswarende omstandighede die verantwoordelikheid opneem om harmoniese en Iiefdevolle verhoudinge in die gesin te stig en te onderhou. Ondersteunings- en begeleidingsprogramme vir ouers en kinders om toereikende opvoedingsbegeleiding en selfaktualisering te verseker, word aanbeveel. Hierdie programme moet op die mikro-, meso- en makrovlak van die samelewing geloods word. / The post-modem society of the 21st century is characterized by dynamic changes which determine the quality of family life and educational support in families. This study aims to determine, by means of a comprehensive literature study and qualitative investigation, the nature, extent and influence of social phenomena on the constitution and maintenance of relationships as well as the quality of educational support in contemporary urban families. Findings show that some families are vulnerable, that relationships deteriorate and that educational support is inadequate as a result of these changes. The decline of norms and values is an aggravating factor in education and adolescence support. Parents and children have to take responsibility to establish harmonious and loving relationships in the family. Support and guidance programmes are recommended for parents and children to ensure adequate educational support and self-actualization. These programmes must be launched on the micro, meso and macro level of society. / Educational studies / M. Ed. (Sosio-Opvoedkunde)
238

Invloed van samelewingsveranderinge op verhoudinge binne die stedelike gesin : 'n sosio-opvoedkundige verkenning / The influence of changing societal phenomena on urban families : a socio-educational analysis

Scholtz, Renée 01 1900 (has links)
Die 21ste eeuse postmodeme samelewing word gekenmerk deur dinamiese veranderinge op aile gebiede wat die kwaliteit van die gesinslewe en opvoedingsbegeleiding binne gesinne bepaaL Hierdie studie poog om aan die hand van 'n omvangryke literatuurstudie en kwalitatiewe ondersoek, die aard, omvang en invloed van sodanige samelewingsverskynsels op verhoudingstigting- en onderhouding en die kwaliteit van opvoedingsbegeleiding in eietydse stadsgesinne te bepaal. Bevindinge toon dat sommige gesinne, as gevolg van hierdie veranderinge, uiters kwesbaar is, dat verhoudinge ontaard en opvoedingsbegeleiding ontoereikend voltrek. Die verval van norme en waardes is veral verswarend vir opvoeding en volwassewordingshulp. Ouers en kinders moet onder verswarende omstandighede die verantwoordelikheid opneem om harmoniese en Iiefdevolle verhoudinge in die gesin te stig en te onderhou. Ondersteunings- en begeleidingsprogramme vir ouers en kinders om toereikende opvoedingsbegeleiding en selfaktualisering te verseker, word aanbeveel. Hierdie programme moet op die mikro-, meso- en makrovlak van die samelewing geloods word. / The post-modem society of the 21st century is characterized by dynamic changes which determine the quality of family life and educational support in families. This study aims to determine, by means of a comprehensive literature study and qualitative investigation, the nature, extent and influence of social phenomena on the constitution and maintenance of relationships as well as the quality of educational support in contemporary urban families. Findings show that some families are vulnerable, that relationships deteriorate and that educational support is inadequate as a result of these changes. The decline of norms and values is an aggravating factor in education and adolescence support. Parents and children have to take responsibility to establish harmonious and loving relationships in the family. Support and guidance programmes are recommended for parents and children to ensure adequate educational support and self-actualization. These programmes must be launched on the micro, meso and macro level of society. / Educational studies / M. Ed. (Sosio-Opvoedkunde)

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