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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.
111

Functionalisation and characterisation of carbon blacks and their incorporation into HDPE and EVA polymer matrices to form conducting composites

Mather, Paul J. January 1996 (has links)
No description available.
112

Internationalisation of Chinese hotel companies : a case study of Guang Dong (International) Hotel Management Limited

Zhou, Yu (Josephine) January 2000 (has links)
The rapid growth of the Chinese economy is reflected in the global expansion of Chinese enterprises. While a lot of attention has been devoted to the expansion of foreign owned enterprises in China since 1978, the interest of this study has extended to Chinese owned service firms which are venturing abroad, with a particular focus on a Chinese hotel chain-Guangdong (International) Hotel Management Limited. This research undertakes an exploratory study - based on inductive and evaluative approach - to generate new, analytical insights into the social phenomenon of a Chinese hotel chain's internationalisation. In entering in international hotel marketplace, Mainland Chinese companies face a very competitive environment in which most of the major players have already achieved strong market positions. Based on consideration of theories and analysis of the empirical evidence, this study develops a theoretical framework of the internationalisation of Chinese hotel companies which is linked to the specific characteristics of the country in transition from a centrally-planned economy to a market economy.
113

Common Techniques in Graceful Tree Labeling with a New Computational Approach

Guyer, Michael 17 May 2016 (has links)
The graceful tree conjecture was first introduced over 50 years ago, and to this day it remains largely unresolved. Ideas for how to label arbitrary trees have been sparse, and so most work in this area focuses on demonstrating that particular classes of trees are graceful. In my research, I continue this effort and establish the gracefulness of some new tree types using previously developed techniques for constructing graceful trees. Meanwhile, little work has been done on developing computational methods for obtaining graceful labelings, as direct approaches are computationally infeasible for even moderately large trees. With this in mind, I have designed a new computational approach for constructing a graceful labeling for trees with sufficiently many leaves. This approach leverages information about the local structures present in a given tree in order to construct a suitable labeling. It has been shown to work for many small cases and thoughts on how to extend this approach for larger trees are put forth. / McAnulty College and Graduate School of Liberal Arts; / Computational Mathematics / MS; / Thesis;
114

Une étude de faisabilité pour une meilleure utilisation dans le matériau béton de granulats « potentiellement réactifs » vis-à-vis de la réaction alcali-silice / A feasibility study to better use in the concrete material "potentially reactive" aggregates towards alkali-silica reaction

Moundoungou, Idriss 27 April 2010 (has links)
Les travaux de cette thèse ont permis de quantifier la réactivité de granulats silex et calcaires siliceux grâce à des études en milieu réactionnel modèle. Le suivi d’éprouvettes de béton a montré que plus des bétons contiennent de granulats « riches » en silice réactive (supérieur à 5%) moins ils gonflent mettant ainsi en évidence l’apparition d’un effet pessimum. En revanche, dans le cas des matériaux « pauvres » en silice réactive (inférieur à 5%) la réduction de l’expansion ne s’observe plus. Il a été montré que, grâce à un processus de neutralisation non délétère pour le béton, les phases siliceuses réactives sont capables de fixer des alcalins sans être dégradées, au travers des silanols initiaux, jusqu’à un certain seuil. Ce seuil en alcalins est rarement dépassé dans le volume granulaire des bétons constitués de sable et de gravillons « riches » en silice réactive. L’augmentation de la température de cure de 38 à 60°C a permis l’observation d’une diminution de l’expansion et l’apparition d’un effet pessimum pour les bétons à base de granulats « pauvres » en silice réactive. Ce changement s’expliquerait par une compétition entre un mécanisme non délétère de neutralisation des alcalins (favorisé à 60°C) et le processus de dégradation de la silice consécutive à une forte concentration locale des alcalins (favorisé à 38°C). La compétition entre ces deux mécanismes est due à un écart de diffusion des alcalins à l’intérieur du réseau siliceux. / The works of this thesis have allowed to quantify the reactivity of flint and siliceous limestone aggregates through studies in model media. Monitoring of concrete samples showed that more is the "rich" silica reactive (greater than 5%) aggregates in concrete, unless they swell highlighting the emergence of pessimum effect. In contrast, in the case of "poor" reactive silica (less than 5%) materials, reduction of the expansion is no longer apparent. It has been shown that through a process of neutralization witch is not damageable for concrete, reactive siliceous phases are capable of fixing alkalis without being degraded through initial silanols, until a certain threshold. This alkalis threshold was rarely exceeded in the granular volume of concrete based on fine and course aggregates witch are “rich” in reactive silica. The increase in curing temperature from 38 to 60°C allowed the expansion reduction and the emergence of a pessimum effect for concretes containing “poor” reactive silica. This change is explained by a competition between a non-deleterious mechanism of neutralization of alkalis (favoured at 60 ° C) and the degradation of silica resulting in a high local concentration of alkalis (favoured at 38 ° C). The competition between these two mechanisms is due to a differential diffusion of alkalis inside the silica network.
115

Timber trade policy and industrialisation : implication for forest harvest and environment in Malaysia

Muhamad, Barudin January 2000 (has links)
Shortage of timber input for processing industries is the main issue facing the Malaysian forest sector. The need to implement policies which will ease the pressure on timber shortage and induce the expansion of forest sector industry, development of rubberwood sector in Malaysia is becoming increasingly urgent. The Malaysian government has announced and implemented three main policies: timber market restriction, encourage utilisation of rubberwood and promotion of lesser-known timber species (LKS). Application of timber market restriction policies has a considerable dispute; firstly because of widespread disagreement over the effect on efficiency of utilisation of timber that lead to timber harvest and deforestation and secondly it will undermine the government effort to promote utilisation of rubberwood and lesser known species. In this thesis, an attempt has been made to enlarge the available empirical knowledge of such effect through a. multi-sectoral forest - rubberwood sector model simulation. An analytical framework is developed, focusing on three major product of the forest sector; log, sawnWood and plywood, and two major products of rubberwood sector; rubberwood log and sawn rubberwood. The framework is used to developed an empirical model of forest-rubberwood and analysed the effect of market restriction policy on forest harvest behaviour, sawnwood and plywood development, rubberwood sector development and change in forest cover. The production, consumption and export of timber, sawnwood, plywood, rubberwood and sawn rubberwood, and change in forest cover have been examined in relation to a number of market policies: export taxes, export ban and import ban, and other alternative policies; royalty, exchange rate, wood utilisation efficiency and subsidies. A series of simulations was undertaken to describe the effect of these policies. The analysis suggests that export restriction on processed timber product will reduced the timber harvest and improved the forest cover but will hinder or distort the development of rubberwood sector and utilisation of less timber species. Related to the deforestation, the notion of environmental Kuznets curve is also examined. The results does not support the existence of this notion for Malaysia. In addition to sectoral analysis, an extended analysis using species harvest was undertaken, as a new approach to investigate efficiency of utilisation of wood resource and forest cover. The results show that promotion of species utilisation will not be achieved with the implementation of market restriction policy on forest products. Species analysis also indicate that in the absence of full data on the quantity of forest harvest, species harvest data would be a good alternative to estimate the effect of policies on forest cover.
116

The Fur Trade in the Northwest as an Instrument of National Expansion, 1821-1846

Sellars, Richard West 08 1900 (has links)
This thesis examines the history of the fur trade in the American northwest during the first half of the nineteenth century.
117

The South and the Mexican War

Lowe, Billie Lynne Owens 12 1900 (has links)
This thesis examines newspapers and correspondence of public men in the era of the Mexican war to provide some answers to pertinent questions regarding the South's role in the Mexican War. It attempts to reveal to some degree whether Southerners uniformly supported the war, whether their support arose from an expansionist sentiment or a desire to extend the area of slavery, whether any strong opposition to the war existed in the South, and why they supported or opposed it.
118

Extracting and exploiting word relationships for information retrieval

Cao, Guihong January 2008 (has links)
Thèse numérisée par la Division de la gestion de documents et des archives de l'Université de Montréal.
119

Understanding the Genetic Consequences of Rapid Range Expansion: A Case Study Using the Invasive Microstegium vimineum Trin. (Poaceae)

Baker, Stephen 24 July 2009 (has links)
Global temperature changes are predicted to influence the distributions of plants and can have significant consequences for population genetic structure. Both the nature of these consequences and the processes that shape them are of interest for both conservation genetics and the development of realistic management programs. Rapid range expansion occurs on short temporal scales not conducive to conventional phylogeographical analyses. This paper presents the findings from a population genetic study of the invasive grass Microstegium vimineum Trin. A. Camus throughout the James River Basin of Virginia. Genotypic analysis using Amplified Fragment Length Polymorphism (AFLP) molecular markers were used to test for evidence of rapid range expansion and the effects associated with colonization and spread of Microstegium vimineum. Within the James River Basin three genetically distinct clusters were identified that were not clearly associated with natural geographic boundaries and recent founder events were also inferred. The James River Basin also appears to act as a corridor for long-distance dispersal events. These findings contribute to our knowledge of the genetic consequences of rapid range expansion for invasive species, and more importantly, native species. Contrary to several studies, the present research also indicates that long-distance dispersal is not rare and can be a major contributor to the genetic structure following range expansion.
120

Sonic crystal noise barriers

Chong, Yung Boon January 2012 (has links)
An alternative road traffic noise barrier using an array of periodically arranged vertical cylinders known as a Sonic Crystal (SC) is investigated. As a result of multiple (Bragg) scattering, SCs exhibit a selective sound attenuation in frequency bands called band gaps or stop bands related to the spacing and size of the cylinders. Theoretical studies using Plane Wave Expansion (PWE), Multiple Scattering Theory (MST) and Finite Element Method (FEM) have enabled study of the performance of SC barriers. Strategies for improving the band gaps by employing the intrinsic acoustic properties of the scatterer are considered. The use of the tube cavity (Helmholtz type) resonances in Split Ring Resonator (SRR) or the breathing mode resonances observed in thin elastic shells is shown to increase Insertion loss (IL) in the low-frequency range below the first Bragg stop band. Subsequently, a novel design of composite scatterer uses these 2 types of cylindrical scatterer in a concentric configuration with multiple symmetrical slits on the outer rigid shell. An array of composite scatterers forms a system of coupled resonators and gives rise to multiple low-frequency resonances. Measurements have been made in an anechoic chamber and also on a full-scale prototypes outdoors under various meteorological conditions. The experimental results are found to confirm the existence of the Bragg band gaps for SC barriers and the predicted significant improvements when locally resonant scatterers are used. The resonant arrays are found to give rise to relatively angle-independent stop bands in a useful range of frequencies. Good agreement between computational modelling and experimental work is obtained. Studies have been made also of the acoustical performances of regular arrays of cylindrical elements, with their axes aligned and parallel to a ground plane including predictions and laboratory experiment.

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