Three Partition Refinement Algorithms

We present improved partition refinement algorithms for three problems: lexicographic sorting, relational coarsest partition, and double lexical ordering. Our double lexical ordering algorithm uses a new, efficient method for unmerging two sorted sets

Estimating the Firm’s Demand for Human Resource Management Practices

This dissertation investigates two related aspects of firms’ choice of HRM practices. The first is why some firms expend a great deal of resources on HRM practices for each employee while others spend very little; the second is the extent to which firms’ bundles of HRM practices sort into general discrete employment systems. In order to empirically address these issues, this dissertation uses an economics-based theoretical approach. The key theoretical link to economics is to treat HRM as a separate factor input in the production process, which allows me to derive an HRM input demand function. This function expresses the firm’s per employee expenditures on HRM and their choice of HRM system as a function of prices and internal and external firm characteristics. Ordinary least squares, two-stage least squares and linear quantile analysis are used to empirically estimate the HRM demand function using a unique dataset of several hundred firms collected by the Bureau of National Affairs (BNA). The regression equation is found to be statistically significant, implying firms do have an identifiable demand for HRM practices. Second, there are nine independent variables which are found to be stable determinants of the demand for per employee expenditures on HRM practices. Regarding the existence of discrete employment systems, cluster analysis is used to determine if the sets of HRM practices adopted by these firms sort into identifiable types of HRM systems. The results show that there is a discrete set of four HRM systems; however, the HRM demand function does not predict which system a firm will choose

A sociophonetic analysis of contact Spanish in the United States : labiodentalization and labial consonant variation

The term labiodentalization is used in this dissertation to describe the linguistic phenomenon consisting in the realization of /b/, which generally corresponds to the voiced bilabial segments [b] and [beta] in Standard varieties of Spanish, as the labiodental fricative consonant [v]. The main goal of this dissertation is to analyze the effects of language contact on labiodentalization of the phoneme /b/ and labial consonant variation in Texas Spanish, with special emphasis on orthography and its influence on bilingual phonology. This project analyzes labial consonant variation in the Spanish of El Paso, Texas, from the perspectives of contact and variationist sociolinguistics. Specifically, it examines (i) if Spanish speakers from El Paso produce an auditorily perceptible distinction between [v] and [beta] or [b] as discrete categories; (ii) if they make an acoustically measurable distinction between these categories; and (iii) which sociolinguistic factors condition the use of and the distribution of [v] in the speech community. In pursuing these questions, a hybrid experimental approach that includes auditory and acoustic analyses for a production study is employed. Results reveal that bilingual speakers from El Paso, Texas make an auditorily perceptible distinction between the voiced bilabial and labiodental segments. Moreover, this distinction is correlated with the linguistic variables of consonant orthography and within-word position, while the most relevant social factors in relation to labiodentalization are English writing proficiency level, Spanish writing competence, and gender. Lastly, the best acoustic predictors for labial variation in the dialect examined are relative intensity and duration.Spanish and Portugues

Variation and change in the vowel system of Tyneside English

PhD ThesisThis thesis presents a variationist account of phonological variation and change in the vowel system of Tyneside English. The distributions of the phonetic exponents of five vowel variables are assessed with respect to the social variables sex, age and social class. Using a corpus of conversational and word-list material, for which 32 speakers of Tyneside English were recorded, between 30 and 40 tokens per speaker of the variables (i), (u), (e), (o) and (3) were transcribed impressionistically and subclassified by following phonological context. The results of this analysis are significant on several counts. First, the speakers sampled appear to differentiate themselves within the speech community through the variable use of certain socially marked phonetic variants, which can be correlated with the sex, age and class variables. Secondly, the speakers style shift to a greater or lesser degree according to combinations of the three social factors, such that surface variability is reduced as a function of increased formality. Third, the overall pattern among the sample population seems to be one of increasing uniformity or convergence: it is speculated that social mobility among upper working- and lower-middle class groups may lead to accent levelling, whereby local speech forms are supplanted by supra-local or innovative intermediate ones. That is, the patterns observed here may be indicative of change in progress. Last, a comparison of the results for the (phonologically) paired variables (i u) and (e o) shows a strong tendency for Tyneside speakers to use these 'symmetrically', in that choice of variant in one variable predicts choice of variant in the other. It is suggested that the symmetry in the system is exploited by Tyneside speakers for the purposes of indicating social affiliation and identity, and is in this sense an extra sociolinguistic resource upon which speakers can draw. In addition, the variants of (3) are discussed with reference to the reported merger of this variable with (a); it is suggested that the apparent 'unmerging' of these two classes is unproblematic from a structural point of view, as the putative (3)—(o) merger appears never to have been completed.UK Economic and Social Research Council (award number R00429524350

Numerical and experimental study of transient laminar natural convection of high prandtl number fluids in a cubical cavity

NUMERICAL AND EXPERIMENTAL STUDY OF TRANSIENT LAMINAR NATURAL CONVECTION OF HIGH PRANDTL NUMBER FLUIDS IN A CUBICAL CAVITYObai Younis Taha ElaminLa convección natural en espacios cerrados, se encuentra ampliamente en sistemas naturales e industriales. El objetivo general de este trabajo es desarrollar y validar una herramienta de simulación capaz de predecir las tasas de enfriamiento de aceite en un tanque. Esta herramienta ha de tener en cuenta la variación de la viscosidad del aceite para dar información detallada de las tasas de enfriamiento del aceite bajo diferentes condiciones de contorno térmicas realisticas. En primer lugar, la influencia de diferentes condiciones de contorno térmicas en las paredes, la variación de la viscosidad y la conductividad de la pared en la convección natural del flujo laminar transitorio en una cavidad cúbica con seis paredes térmicamente activo están analizadas.Para analizar el efecto individual de las paredes laterales de la cavidad en el proceso de enfriamiento, la segunda parte de este estudio considera que, tanto numéricamente como experimentalmente, la transición de la convección natural laminar en una cavidad cúbica con dos paredes opuestas frías y verticales.Nuevas relaciones de escala que tengan en cuenta la variación de la viscosidad con la temperatura, no publicadas anteriormente en la literatura, se derivan de las velocidades de la capa límite, por el tiempo necesario para la capa límite para alcanzar el estado estacionario y para la velocidad y el espesor de las intrusiones horizontales.NUMERICAL AND EXPERIMENTAL STUDY OF TRANSIENT LAMINAR NATURAL CONVECTION OF HIGH PRANDTL NUMBER FLUIDS IN A CUBICAL CAVITYObai Younis Taha ElaminFree convection in enclosed spaces is found widely in natural and industrial systems. The general objective of this work is to develop and validate a simulation tool able to predict the cooling rates of oil in a tank. This tool has to take into account the variation of the oil viscosity to give detailed information of the cooling rates of the oil under different realistic thermal boundary conditions. First, the influence of different thermal wall boundary conditions, the variation of the viscosity and the wall conductivity on the transient laminar natural convection flow in a cubical cavity with the six walls thermally active is studied numerically. To analyze the individual effect of the side walls of the cavity on the cooling process, the second part of this study considers, numerically and experimentally, the transient laminar natural convection in a cubical cavity with two cold opposite vertical walls. The shadowgraph technique is employed to visualize the development of the transient convective flow. New scaling relations that take into account the viscosity variation with temperature, not reported previously in the literature, are derived for the boundary layer velocities, for the time needed for the boundary layer to reach the steady state and for the velocity and thickness of the horizontal intrusions

Syntax with oscillators and energy levels

This book presents a new approach to studying the syntax of human language, one which emphasizes how we think about time. Tilsen argues that many current theories are unsatisfactory because those theories conceptualize syntactic patterns with spatially arranged structures of objects. These object-structures are atemporal and do not lend well to reasoning about time. The book develops an alternative conceptual model in which oscillatory systems of various types interact with each other through coupling forces, and in which the relative energies of those systems are organized in particular ways. Tilsen emphasizes that the two primary mechanisms of the approach – oscillators and energy levels – require alternative ways of thinking about time. Furthermore, his theory leads to a new way of thinking about grammaticality and the recursive nature of language. The theory is applied to a variety of syntactic phenomena: word order, phrase structure, morphosyntax, constituency, case systems, ellipsis, anaphora, and islands. The book also presents a general program for the study of language in which the construction of linguistic theories is itself an object of theoretical analysis

Syntax with oscillators and energy levels

This book presents a new approach to studying the syntax of human language, one which emphasizes how we think about time. Tilsen argues that many current theories are unsatisfactory because those theories conceptualize syntactic patterns with spatially arranged structures of objects. These object-structures are atemporal and do not lend well to reasoning about time. The book develops an alternative conceptual model in which oscillatory systems of various types interact with each other through coupling forces, and in which the relative energies of those systems are organized in particular ways. Tilsen emphasizes that the two primary mechanisms of the approach – oscillators and energy levels – require alternative ways of thinking about time. Furthermore, his theory leads to a new way of thinking about grammaticality and the recursive nature of language. The theory is applied to a variety of syntactic phenomena: word order, phrase structure, morphosyntax, constituency, case systems, ellipsis, anaphora, and islands. The book also presents a general program for the study of language in which the construction of linguistic theories is itself an object of theoretical analysis. Reviewed by John Goldsmith, Mark Gibson and an anonymous reviewer. Signed reports are openly available in the downloads session

Syntax with oscillators and energy levels

This book presents a new approach to studying the syntax of human language, one which emphasizes how we think about time. Tilsen argues that many current theories are unsatisfactory because those theories conceptualize syntactic patterns with spatially arranged structures of objects. These object-structures are atemporal and do not lend well to reasoning about time. The book develops an alternative conceptual model in which oscillatory systems of various types interact with each other through coupling forces, and in which the relative energies of those systems are organized in particular ways. Tilsen emphasizes that the two primary mechanisms of the approach – oscillators and energy levels – require alternative ways of thinking about time. Furthermore, his theory leads to a new way of thinking about grammaticality and the recursive nature of language. The theory is applied to a variety of syntactic phenomena: word order, phrase structure, morphosyntax, constituency, case systems, ellipsis, anaphora, and islands. The book also presents a general program for the study of language in which the construction of linguistic theories is itself an object of theoretical analysis. Reviewed by John Goldsmith, Mark Gibson and an anonymous reviewer. Signed reports are openly available in the downloads session

Syntax with oscillators and energy levels

This book presents a new approach to studying the syntax of human language, one which emphasizes how we think about time. Tilsen argues that many current theories are unsatisfactory because those theories conceptualize syntactic patterns with spatially arranged structures of objects. These object-structures are atemporal and do not lend well to reasoning about time. The book develops an alternative conceptual model in which oscillatory systems of various types interact with each other through coupling forces, and in which the relative energies of those systems are organized in particular ways. Tilsen emphasizes that the two primary mechanisms of the approach – oscillators and energy levels – require alternative ways of thinking about time. Furthermore, his theory leads to a new way of thinking about grammaticality and the recursive nature of language. The theory is applied to a variety of syntactic phenomena: word order, phrase structure, morphosyntax, constituency, case systems, ellipsis, anaphora, and islands. The book also presents a general program for the study of language in which the construction of linguistic theories is itself an object of theoretical analysis. Reviewed by John Goldsmith, Mark Gibson and an anonymous reviewer. Signed reports are openly available in the downloads session

Syntax with oscillators and energy levels

This book presents a new approach to studying the syntax of human language, one which emphasizes how we think about time. Tilsen argues that many current theories are unsatisfactory because those theories conceptualize syntactic patterns with spatially arranged structures of objects. These object-structures are atemporal and do not lend well to reasoning about time. The book develops an alternative conceptual model in which oscillatory systems of various types interact with each other through coupling forces, and in which the relative energies of those systems are organized in particular ways. Tilsen emphasizes that the two primary mechanisms of the approach – oscillators and energy levels – require alternative ways of thinking about time. Furthermore, his theory leads to a new way of thinking about grammaticality and the recursive nature of language. The theory is applied to a variety of syntactic phenomena: word order, phrase structure, morphosyntax, constituency, case systems, ellipsis, anaphora, and islands. The book also presents a general program for the study of language in which the construction of linguistic theories is itself an object of theoretical analysis. Reviewed by John Goldsmith, Mark Gibson and an anonymous reviewer. Signed reports are openly available in the downloads session