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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.
41

An investigation of braided river dynamics using a new numerical modelling approach

Cudden, Judith Rose January 2002 (has links)
Braided Cascade has been developed from Cascade (Braun and Sambridge, (1997)), a long-term (dt = 100 years) numerical model that simulates long-term landscape evolution. Herein it has been modified and applied to relatively short term process modelling of the evolution of complex river topography, discharge and sediment load of braided rivers. Braided Cascade is synthesist in spirit, there is no detailed hydrodynamic component to the model, a realistic simplification at the time scales considered. The major advantage of the model is the incorporation of an irregular time-varying grid using a triangulated irregular network (TIN) to represent a terrain surface. Advantages of using TINs include the ability to solve problems with non-rectangular geometeries and/or boundary conditions and the ability of river segments to form in all directions. The model routes water from node to node based on the local topographic slope. Sediment transport depends on the local stream power. Nodal elevation changes after each iteration according to the difference between the amount of sediment entering and leaving the node. Model output includes spatial and temporal (at one point) water discharge, bedload sediment transport, as well as maps of channel networks, erosion and deposition throughout the reach. Sensitivity analysis indicated that the most significant parameters for braiding are erosion length scale, splitting ratios and the allowance of the model to deposit sediment. Therefore an imbalance in the amount of sediment the river is carrying and the carrying capacity AND a reworking of the deposits is needed for a braided network to form. Sediment output from model runs indicate that the similarities between model data and other data sets are weak and all runs tended to reach static equilibrium. Braided Cascade therefore failed to adequately reproduce realistic data sets. It was found that the differences between model results and the flume data indicate that the model does not always match the physical systems as closely as physical systems match each other.
42

Does geography matter? an empirical investigation into neighbourhood, peer effects and electricity consumption

Weinhardt, Felix Julian January 2012 (has links)
This thesis consists of four distinct projects which sit at the crossroad between Labour, Education and Environmental Economics. The underlying and unifying theme is the examination of social and geographical inequalities using applied econometrics. In the first project, I estimate the effect of moving into a deprived high-density social housing neighbourhood on the educational attainments of teenagers in England. I exploit the timing of moving, which can be taken as exogenous because of long waiting lists for social housing in high-demand areas, to avoid the usual sorting problems. Using this strategy, I find no evidence for negative effects. The second project investigates the effect of neighbours' characteristics and prior achievements on teenagers' educational outcomes. The study relies on mover-induced variation in neighbourhood quality, whilst controlling for general gentrification trends and other unobservables. The results provide little evidence for significant effects on pupil test score progression. The third project looks at the size, significance and heterogeneity of ability peer effects in secondary schools in England. The methodological innovation is to identify ability peer effects using within-pupil-across-subject variation in students' test scores and peer prior achievements. The chapter shows that it is the low- and high-achievers, who account for most or all of the effect of average peer quality on the educational outcomes of other pupils and that this effect varies across genders. The final project presents -to the best of my knowledge- the first nationwide empirical assessment of residential electricity use in response to the timing of daylight for the US. Employing Geographical Information Systems (GIS), I calculate the solar times of sunrise and sunset for all locations in mainland US and show that two distinct sources of geographical variation can be used to estimate county-level responses in residential electricity consumption. Using both approaches I find that early sunrise is associated with lower residential electricity use in the North, but higher consumption in the South. This is a novel finding with potentially significant policy implications and I offer some suggestions about how future research should examine the behavioural channels that could cause these results.
43

Nationalism and tourist-host relationships : a case study of Bala, North Wales

Griffiths, Ingrid A. January 2011 (has links)
Within the domain of tourism, tourist-host relationships are dynamic and complex. The nature of interaction between tourist and host potentially renders a destination more or less desirable to tourists and this, in turn, may impact upon the development and promotion of tourism for that destination. In particular, differences between tourists and hosts will influence the kind of relationship that emerges at the points of contact between them. In ‘intra-national’ settings, where tourists from one country interact with hosts from another, such differences will inevitably be in evidence. Thus, understanding the relevance of nationalism to tourist-host relationships is fundamental to the management of tourism in these contexts. To date, however, little academic attention has been paid to nationalistic determinants of tourist-host encounters. The purpose of this thesis is to address this gap in the literature. Critically exploring the influences of nationalism within tourist-hosts relationships, it focuses specifically on the case of Bala, a small community and tourist destination in North Wales, identifying and appraising the extent and implications of nationalism on the relationship between English tourists and Welsh hosts. Utilising Q method, a technique designed for the systematic study of subjectivity, the research seeks to elicit English tourists’ and Welsh hosts’ subjectivities concerning nationalism, and by association, uncover subjectivities towards national identities, culture and tourism. It reveals that, fundamentally, nationalism does influence the nature of the relationship between English tourists and Welsh hosts in a number of ways, particularly with respect to nationalistic understanding, perceptions of self in relation to others and perception of others. However, the research also indicates that the nature of relationships between tourists and hosts is essentially an ongoing social process which, given time, will reach an organic equilibrium condition. As a consequence, tourism policy and process interventions to manage tourist-host relationships are considered futile within ‘intra-national’ environments.
44

The economic interrelationships of tourism : a computable general equilibrium analysis

Gillham, Jonathan January 2005 (has links)
This thesis investigates the economic interrelationships that tourism has in the wider economy in the context of a country that is heavily reliant on tourism revenues. More specifically, it seeks to examine the welfare, intersectoral, distributional, competitive, investment and dynamic issues relating to the tourism sector that have been under investigated in both the tourism and trade literature. These issues have been investigated empirically using Computable General Equilibrium (CGE) analysis. The thesis is set out as follows: Chapter 1 sets out the relative position of Spain in terms of its international competitors and defines the tourism sector. It also explains why CGE modelling is felt to be the most suitable approach for modelling the Spanish tourism sector for the purposes of this thesis. It also presents an overview of the planned research. Chapter 2 gives an overview of the structure and key features of the Spanish economy. It discusses the evolution of the tourism sector and how it varies between the different autonomous communities in Spain. The Spanish Tourism Satellite Account is presented and Spanish tourism policy is examined. Chapter 3 reviews the theoretical and empirical literature on CGE modelling and tourism analysis relevant to this thesis. Various types of CGE model are scrutinised and their usefulness assessed. The role of tourism in international trade is considered and the characteristics of the tourism sector that need to be embodied into a CGE model are discussed. Chapter 4 describes the core CGE model used in this thesis and the underlying equations that are associated with it. The central data set used is the Spanish input-output table for 1996. This data set is described and all subsequent input-output tables used in other chapters are amended so as to be consistent with this data set. Closure rules, elasticity parameters, solution methods and calibration methods are also discussed. Chapter 5 presents the results of the experiments carried out with the dynamic Spanish national CGE model. The core model presented in Chapter 4 has been extended to incorporate foreign direct investment and these changes are disclosed in the opening sections. Counterfactuals are designed so as to estimate the impact of foreign direct investment inflows and tourism demand shocks on the Spanish economy. Sensitivity analysis of the key exogenous parameters is also undertaken. Chapter 6 presents the results of the experiments carried out on the static regional CGE model of the regions of Spain. Input-Output tables for four of Spain's autonomous regions were obtained and integrated with the Spanish national table to create a data set which accounts for the four regions analysed and the remainder of the Spanish economy. The model presented in Chapter 4 is adapted to incorporate regional trade flows and structural differences are discussed. Counterfactuals are designed in order to investigate how regional tax policy might affect tourism flows in Spain and how tourism demand impacts on different regions in Spain. Sensitivity analysis of the key exogenous parameters is also undertaken. Chapter 7 presents the results of the experiments of the dynamic CGE model for the Canary Islands. The core model is identical to that presented in Chapter 4, except that it is applied at a sub-national rather than a national level. Counterfactuals are designed so as to take account of the issues affecting a small island economy that is heavily reliant on tourism. As before, sensitivity analysis of the key exogenous parameters is also undertaken. Chapter 8 summarises the findings of this study, highlights possibly policy implications and cites limitations of the research. Suggestions for further research are also highlighted.
45

Factors influencing the accuracy of remote sensing classifications : a comparative study

Pal, Mahesh January 2002 (has links)
Within last 20 years, a number of methods have been employed for classifying remote sensing data, including parametric methods (e.g. the maximum likelihood classifier) and non-parametric classifiers (such as neural network classifiers).Each of these classification algorithms has some specific problems which limits its use. This research studies some alternative classification methods for land cover classification and compares their performance with the well established classification methods. The areas selected for this study are located near Littleport (Ely), in East Anglia, UK and in La Mancha region of Spain. Images in the optical bands of the Landsat ETM+ for year 2000 and InSAR data from May to September of 1996 for UK area, DAIS hyperspectral data and Landsat ETM+ for year 2000 for Spain area are used for this study. In addition, field data for the year 1996 were collected from farmers and for year 2000 were collected by field visits to both areas in the UK and Spain to generate the ground reference data set. The research was carried out in three main stages.The overall aim of this study is to assess the relative performance of four approaches to classification in remote sensing - the maximum likelihood, artificial neural net, decision tree and support vector machine methods and to examine factors which affect their performance in term of overall classification accuracy. Firstly, this research studies the behaviour of decision tree and support vector machine classifiers for land cover classification using ETM+ (UK) data. This stage discusses some factors affecting classification accuracy of a decision tree classifier, and also compares the performance of the decision tree with that of the maximum likelihood and neural network classifiers. The use of SVM requires the user to set the values of some parameters, such as type of kernel, kernel parameters, and multi-class methods as these parameters can significantly affect the accuracy of the resulting classification. This stage involves studying the effects of varying the various user defined parameters and noting their effect on classification accuracy. It is concluded that SVM perform far better than decision tree, maximum likelihood and neural network classifiers for this type of study. The second stage involves applying the decision tree, maximum likelihood and neural network classifiers to InSAR coherence and intensity data and evaluating the utility of this type of data for land cover classification studies. Finally, the last stage involves studying the response of SVMs, decision trees, maximum likelihood and neural classifier to different training data sizes, number of features, sampling plan, and the scale of the data used. The conclusion from the experiments presented in this stage is that the SVMs are unaffected by the Hughes phenomenon, and perform far better than the other classifiers in all cases. The performance of decision tree classifier based feature selection is found to be quite good in comparison with MNF transform. This study indicates that good classification performance depends on various parameters such as data type, scale of data, training sample size and type of classification method employed.
46

Theoretical and empirical issues in tourism demand analysis

De Mello, Maria M. M. Q. January 2001 (has links)
The majority of empirical studies of tourism analysis use a static single equation approach to model the demand for tourism of one origin for one or more destination countries. The examination of such studies generally shows that the economic interpretation and policy implications drawn as conclusions are based on mis-specified models, invalid estimation and inference procedures, inconsistent estimates and poor forecasting performance. Static single equation models of tourism demand tend to neglect interdependencies among destinations, ignore nonstationarity, overlook dynamics and, generally, disregard economic theory. Empirical specifications constrained by these flaws are bound to generate biased and inconsistent estimates upon which no reliable economic analysis or policy implication can be based. In an analytical context that focuses on the UK tourism demand for France, Spain and Portugal in the period 1969-1997, the main objective of this thesis is to demonstrate that consistent elasticities' estimates and reliable forecasts can be obtained from empirical models which are based on the principles of economic theory, and specified and rigorously tested within the rules of sound econometric methodology. The alternative models estimated in chapters 4 to 7 include error-correction autoregressive distributed lag models (ARDL), static and dynamic almost ideal demands systems (AIDS) and cointegrated vector autoregressive models (VAR). The main findings that emerge from the study are as follow. The battery of diagnostic tests applied to the dynamic error-correction ARDL models provide sufficient evidence to classify them as statistically robust, structurally stable and well-defined specifications. The evidence obtained for the AIDS and VAR systems indicates them as data-coherent and theoretically-consistent models, complying with the utility maximisation hypotheses. The similarity, across models, of the estimates of the long-run structural parameters and the accuracy of the forecasts they provide further support the reliability of these models for explaining and predicting the UK tourism demand behaviour, in contrast to the static single equations estimated in chapter 3. The specifications of chapters 4 to 7 can easily be extended, without loss of generality, to more origins and destinations and can be adapted to alternative contexts such as the demand for specific regions within a country, specific resorts within a region or even specific types of tourism products such as accommodation or leisure facilities, within a local area.
47

Heading drift mitigation for low-cost inertial pedestrian navigation

Abdul Rahim, Khairi January 2012 (has links)
The concept of autonomous pedestrian navigation is often adopted for indoor pedestrian navigation. For outdoors, a Global Positioning System (GPS) is often used for navigation by utilizing GPS signals for position computation but indoors, its signals are often unavailable. Therefore, autonomous pedestrian navigation for indoors can be realized with the use of independent sensors, such as low-cost inertial sensors, and these sensors are often known as Inertial Measurement Unit (IMU) where they do not rely on the reception of external information such as GPS signals. Using these sensors, a relative positioning concept from initialized position and attitude is used for navigation. The sensors sense the change in velocity and after integration, it is added to the previous position to obtain the current position. Such low-cost systems, however, are prone to errors that can result in a large position drift. This problem can be minimized by mounting the sensors on the pedestrian’s foot. During walking, the foot is briefly stationary while it is on the ground, sometimes called the zero-velocity period. If a non-zero velocity is then measured by the inertial sensors during this period, it is considered as an error and thus can be corrected. These repeated corrections to the inertial sensor’s velocity measurements can, therefore, be used to control the error growth and minimize the position drift. Nonetheless, it is still inadequate, mainly due to the remaining errors on the inertial sensor’s heading when the velocity corrections are used alone. Apart from the initialization issue, therefore, the heading drift problem still remains in such low-cost systems. In this research, two novel methods are developed and investigated to mitigate the heading drift problem when used with the velocity updates. The first method is termed Cardinal Heading Aided Inertial Navigation (CHAIN), where an algorithm is developed to use building ‘heading’ to aid the heading measurement in the Kalman Filter. The second method is termed the Rotated IMU (RIMU), where the foot-mounted inertial sensor is rotated about a single axis to increase the observability of the sensor’s heading. For the CHAIN, the method proposed has been investigated with real field trials using the low-cost Microstrain 3DM-GX3-25 inertial sensor. It shows a clear improvement in mitigating the heading drift error. It offers significant improvement in navigation accuracy for a long period, allowing autonomous pedestrian navigation for as long as 40 minutes with below 5 meters position error between start and end position. It does not require any extra heading sensors, such as a magnetometer or visual sensors such as a camera nor an extensive position or map database, and thus offers a cost-effective solution. Furthermore, its simplicity makes it feasible for it to be implemented in real-time, as very little computing capability is needed. For the RIMU, the method was tested with Nottingham Geospatial Institute (NGI) inertial data simulation software. Field trials were also undertaken using the same low-cost inertial sensor, mounted on a rotated platform prototype. This method improves the observability of the inertial sensor’s errors, resulting also in a decrease in the heading drift error at the expense of requiring extra components.
48

Modelling the causes and measuring the consequences of cultural tourism : the economic and cultural impacts of cultural tourist attractions

Wang, Jing January 2012 (has links)
A complete view of cultural tourism requires perspectives on both its economic aspect and its cultural dimension. This thesis presents the first cultural tourist taxonomy in the literature, which classifies the various types of cultural tourists by using fundamental distinctions based on economic theory. It also explains the necessity of classifying cultural tourists into those six well-defined categories, and why it should only be six. Building on McKercher and du Cros (2002), it models the causes and measures the consequences of cultural tourism, and develops a framework for evaluating the economic and cultural impacts caused by cultural tourist attractions. The method of evaluating the economic impact of cultural tourist attractions is based on the causal chain model, and it has improved the approach used in Femandez-Young and Young (2008) and Young et al (2010), which attributes to an attraction the amount of tourist expenditure at the destination caused by the existence of the attraction. The method of measuring the cultural impact is a new contribution to the literature, as this study provides a way to quantify the complex concept of cultural impact, using the ideas of meta-preferences and preference formation (Sen, 1977; 1983; 2002). This research has succeeded in developing a theoretically-based and practically applicable method for measuring and combining the economic and cultural impacts of cultural attractions. The methods have been applied to two cultural attractions in Nottingham: Nottingham Contemporary and the Galleries of Justice. The collected empirical results have demonstrated the feasibility and practicability of the evaluation method based on the new taxonomy. The combined evaluation method enables policy-makers to evaluate comprehensively the overall impact of each attraction and locate the attraction in the cultural space by taking both economic and cultural impacts into account.
49

The perceived role of key stakeholders' involvement in sustainable tourism development

Kim, Kyoung Bae January 2013 (has links)
This thesis considers how to improve levels of understanding of different stakeholders' perspectives and their involvement in sustainable tourism development. Jeju Island has been relying on tourism to support the economy and has consequently emerged as the most developed tourist destination in Korea, launched as a result of growth-oriented regional policies of the central and local government over the last thirty years. For sustainable tourism to be successful, it requires the stakeholders' support in the community to develop tourism in a sustainable manner. Therefore, this study focuses on building knowledge about stakeholder perceptions of government led tourism development by investigating stakeholder groups. Also, for this research aim, a qualitative approach was applied, interviews are used to take information for a specific purpose, and this research used semi-structured interviews to obtain relevant information from 42 key informants. For analysis of the qualitative data from the key informants, this study employed Grounded Theory (GT) as a tool for data analysis and interpretation. This research is offers a critical evaluation towards the perceptions and impacts of tourism development and involvement, and investigates their relative influence within the collaboration process. To achieve the collaboration between various stakeholders in supporting the goals and objectives of tourism development, the study presents that the local government should involve local residents more actively in the decision making processes of the tourism development. The study confirms the importance of trust as a key variable in a social exchange relationship between residents' of a host community and government actors and all stakeholders need to be educated and trained to make sustainable tourism development more feasible.
50

Decoding cultural landscapes : guiding principles for the management of interpretation in cultural world heritage sites

Kamel, Ehab January 2011 (has links)
Conserving the cultural significance of heritage sites - as the guardians of social unity, place identity, and national pride - plays an essential role in maintaining sustainable social development, as well as preserving the variations identifying cultural groups and enriching the interaction between them. Consequently, and considering the importance of the built environment in communicating, as well as documenting, cultural messages, this research project, started in 2007, develops a set of guiding principles for interpretation management, as a process for conserving cultural World Heritage Sites; by maintaining and communicating their cultural significance through managing newly added architectural, urban, and landscape designs to such heritage sites. This research was mainly conducted to investigate and explain a concern regarding a gap that is increasing between people and the cultural heritage contexts they reside- particularly in Egypt- and to suggest a strategy for professionals to understand such sites from a perspective that reflects the public cognition. Adopting Grounded Theory methodology, the research develops a series of principles, which are intended to guide the process of cultural heritage conservation; through a critical analysis of current heritage conservation practices in World Heritage Sites. The research shows how they [the guiding principles] correspond to the contemporary perception of cultural heritage in literature, for which, a thorough discussion of literature, as well as critical analysis of UNESCO’s heritage conventions and ICOMOS charters are carried out. The research raises, discusses, and answers several key questions concerning heritage conservation, such as: whether UNESCO’s conventions target the right heritage or not; the conflicts appearing between heritage conservation documents (conventions and charters); whether intangible heritage can be communicated through design; and the effect of Western heritage ideology on heritage conservation practices. This is carried out through the use of interpretive discourse analysis of literature and heritage documents, and personal site observations and questionnaire surveys carried out in two main World Heritage Sites: Historic Cairo in Egypt and Liverpool city in the UK. The two case studies contributed to the understanding of the general public’s perception of cultural Heritage Sites, and how such perception is reflected in current heritage conservation practices. The thesis decodes cultural World Heritage Sites into three intersecting levels: the ‘cultural significances’ (or ‘open codes’), which represent different categories under which people perceive historic urban landscapes; the ‘cultural concepts’ (or ‘axial codes’), which are considered as the objectives of heritage conservation practice, and represent the general concepts under which cultural significances influence the heritage interpretation process; and finally, the ‘interpretation strategy tactics’, the UNCAP Strategy (or the ‘selective coding’), which are the five overarching principles guiding the interpretation management process in cultural heritage sites. This strategy, the UNCAP (Understanding people; Narrating the story; Conserving the spirit of place; Architectural engagement; and Preserving the built heritage), developed throughout this research, is intended to help heritage site managers, curators, architects, urban designers, landscape architects, developers, and decision makers to build up a thorough understanding of heritage sites, which should facilitate the establishment of more interpretive management plans for such sites, and enhance the communication of meanings and values of their physical remains, as well as emphasizing the ‘spirit of place’; for achieving socio-cultural sustainability in the development of World Heritage Sites.

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