• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 292
  • 78
  • 75
  • 47
  • 2
  • 1
  • 1
  • Tagged with
  • 817
  • 433
  • 328
  • 326
  • 326
  • 223
  • 79
  • 77
  • 76
  • 70
  • 69
  • 60
  • 55
  • 48
  • 46
  • 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.
1

Schools as generators of urban change : the relationship between social infrastructure and physical form

Lubinsky, A. January 2009 (has links)
The state-funded compulsory school emerged out of the social turmoil of the late 19th century as a means of training and integrating working class and immigrant children into a changing world. These schools were generally physically impressive buildings, looming over surrounding slums and designed to act as ‘civilising’ influences. This thesis postulates that the school building has, over the last 100 years, also played a larger role in structuring the wider urban environment as a means of facilitating the shifts to a centralised modern industrial economy and, over the course of the last 20 years, to a network-based, choice-based, free market society. The typology of the school buildings, in terms of its size and location, has adapted to perform this role. The first half of this thesis, The School that Built a Town, argues that the modern school, from the early 1900s until the 1980s, was a significant instrument of centralised states in establishing the development of rational ‘neighbourhoods’, with a range of impacts including the control of traffic patterns, the density of residential areas, the distribution of land uses and the provision of community centres. The instrumental relationship between the school building and the neighbourhood unit is explored in the contexts of the United States, the United Kingdom and South Africa. The second half of this thesis, The Implications of School Choice for Urban Structure and School Building Typology, explores the role of the school in a postmodern free market world, where school choice has dramatically ended the historical one-to-one relationship between a school and its surrounding neighbourhood. Three case studies considering areas of London, New York City and Cape Town examine three different school choice policies, each of which exert specific influences on the structure of their wider urban environments.
2

The fragmented morphology of spontaneous settlements : the case study cities of Jeddah (Saudi Arabia) and Zahedan (Iran)

Shafiei, K. January 2013 (has links)
The rapid expansion of spontaneous settlements is an inevitable response to the increasing poor population in the Third World. These urban areas usually exhibit morphologic irregularities that are conventionally associated with enduring poverty. Nonetheless, cases are reported in which simultaneous physical and socio-economic self-improvements gradually transform a degraded settlement to a consolidated area. Accordingly, the thesis aims at revisiting the relation between irregularity and consolidation in spontaneous settlements. The hypothesis is that morphologic irregularity does not impede the consolidation of spontaneous settlements in long-term. A theoretical framework is developed in which consolidation is associated with the gradual fulfilment of dwellers' respective economic and territorial preferences. The theoretical framework also suggests that consolidation is reflected in the formation of local centres within spontaneous settlements. The hypothesis is then tested in two cities of Jeddah (Saudi Arabia) and Zahedan (Iran). Geometric accessibility is the key notion that relates irregularity and consolidation. Firstly, it is illustrated that higher accessibility in intermediate level enforces consolidation. The internal spatial structure of a spontaneous settlement is where higher intermediate accessibility facilitates consolidation through organizing the distribution of commercial land use. Also the lower city-wide accessibility of spontaneous settlements is reported. Irregularity and accessibility are related in the next stage. Irregularity is redefined as fragmentation (or the higher diversity in urban blocks' orientations) to prove that the case study settlements are more fragmented than their formal urban surroundings. Then it is heuristically illustrated that fragmentation decreases the city-wide accessibility of a settlement without impeding the emergence of its internal spatial structure. The thesis concludes that consolidation of a spontaneous settlement is facilitated when the lowered city-wide accessibility caused by fragmentation fulfils the dwellers' territorial preference while at the same time the emerged internal spatial structure satisfies their economic preference in an intermediate accessibility level.
3

Natural hydraulic lime mortars for use in high temperature, high humidity climatic conditions : effect of calcitic fillers

Razali, Nadia Binti January 2014 (has links)
The widespread adoption of alternative binders are playing an increasing role in carbon dioxide (CO2) abatement in green construction and the repair of traditionally built structures. Natural Hydraulic Lime (NHL) has better environmental credentials than Portland Cement (PC) due in part to its lower calcination temperature and its ability to absorb CO2 during carbonation. However, NHL is more sensitive to climatic conditions during the setting and hardening processes and this is especially pronounced in high humidity climates. This research investigated the influence of various types of calcitic fillers (oyster shells, limestone, marble and precipitated calcium carbonate (PCC)) modifications to NHL mortars subjected to high temperature and humidity environments and evaluated the subsequent effect on early development of various chemical and physical properties. Primary mortar parameters such as moisture loss, pH, carbonation depth, flexural strength, compressive strength, sorptivity and microscopy analysis (SEM images) were studied. The results showed that the setting and hardening of those mortars with precipitated calcium carbonate worked most effectively in high humidity environments. The purity and crystallinity of the mineral ‘seeding’ materials was attributed to the positive benefits in the physical characteristics. Additionally, curing at higher temperatures greatly accelerated the hydration reaction of the mortar. It is evident from the findings that modified mortars can increase the performance especially in terms of carbonation rate, flexural strength, compressive strength and sorptivity. Whilst the precipitated calcium carbonate showed positive benefits in early stage setting reactions it did not significantly influence the long term physical characteristics of the mortars. This situation is meaningful for our understanding of modified lime mortars and the seeding materials. This research can be used to influence the specification and product design of NHL materials in high temperature and high humidity environments and this is especially important for its early stage use that has been traditionally associated with reduced set characteristics.
4

Energy performance of traditionally constructed dwellings in Scotland

Ingram, Victoria January 2014 (has links)
This research was commissioned by Historic Scotland, to ascertain what, if any, characteristics specific to traditionally constructed (stone masonry) dwellings in Scotland could impact on the result of an energy assessment. The research uses five case study dwellings, whose energy consumption has been assessed using three separate calculation methodologies: the two Government-accredited steady state methodologies SAP and RdSAP, in addition to a dynamic simulation using the IES Virtual Environment. The research finds primarily that traditionally constructed dwellings use more energy than the UK average, and that certain aspects of the steady state calculation methodologies give erroneous results. These errors are either specific to stone masonry dwellings through application of assumptions with respect to thermal storage and movement, or specific to Scottish dwellings through application of UK average climate variables. Furthermore, there are significant challenges to using dynamic simulations for these dwellings, which may not outweigh the benefits of perceived accuracy by the occupant. Therefore, the research concludes that the steady state methodologies should continue to be utilised, but with the awareness that the methodologies have limitations.
5

The planning and urban design of liveable public open spaces in Oman : case study of Muscat

Aljabri, Hanan January 2014 (has links)
Public open space has performed a considerable role in society since the first human settlements. Since the 1960s the understanding of liveable public open space has grown dramatically as exhibiting good quality and being well-used by the public. There is evidence of the social, economic and environmental benefits of public open spaces in any city. Planning and urban design practice are the mechanisms behind providing liveable public open space which entices and encourages the public to choose to spend more of their spare time in them. This thesis is concerned with liveability in contemporary public open spaces in Middle Eastern cities, where historically public open spaces were developed based on Islamic religion and Sharī‘ah, which provided norms for the production of the built environment and social engagement with this. As a focus for the exploration of contemporary public open space in Middle Eastern cities, this study examines the design of squares and plazas in particular. Squares and plazas were introduced by colonisation and reinforced by modernity, being later emphasised by globalisation. Nevertheless, squares and plazas in the Middle East have not been as successful as the traditional local open spaces, nor as the Western versions. This research has attempted to evaluate the liveability in public open spaces in Muscat through detailed case studies of two squares and two plazas in three ways, including evaluating: the physical quality, users’ perception and professional perception. In order to achieve this, a mixed methods strategy was designed based on the theoretical perspective of social constructionism. These methods included: desk-top study of documents; three built environment assessment tools, applied by professionals; behavioural mapping and observation; a survey of open space users; and semi-structured interviews with professional involved in the provision of public open space and community representatives in Oman. The empirical work showed that though public open spaces are viewed as beautification elements of the city structure, there are major weaknesses in meeting users’ requirements, engaging users and in considering local climate in those spaces. Although the planning and urban design system in Oman has been adopted from the West, it is not established adequately in different plan sequences and strategies to govern the provision process and control the quality of the spaces; in addition, there is lack of clarity and coordination in institutional responsibilities over the provision and management of public open space. It is concluded that providing more liveable public open space in Oman would require improvements to the planning and urban design systems, as well as learning from traditional practice in the production and management of open space in the Middle East.
6

The production of new affordable housing in the Syrian cities : the possible role of procurement processes in improving construction efficiency

Al Khalaf, Aseel January 2014 (has links)
Despite the Syrian government’s commitment to provide adequate and affordable housing, through housing programmes implemented over successive five-year development plans, there is still a shortage of affordable homes for low-income people. This shortfall can be attributed to constraints at two basic levels: housing system design (strategic level) and housing system implementation (operational level). Housing policies and construction practices systematically lack the proper strategies and sophisticated approaches for change. In contrast, the UK government has adopted strategic and operational mechanisms for enforcing change in publically-funded projects through a reform agenda (policy package) aimed at creating innovative collaborative relationships between client organisations, and private sector consortia. In this, the procurement processes were seen as a key driver to stimulate change for effective provision of affordable housing. This study aimed to investigate possible efficiency improvements in the affordable housing supply process in Syria, focusing on the role of more sophisticated approaches to project delivery, i.e. the procurement process. Data collected through a literature review and interviews with key informants from both the UK and Syria, forms the basis for a comparative assessment on how lessons learned from the UK experience can be applied in the Syrian context. This study advocates a holistic, top-down process involving the legal, cultural, technical and financial aspects of affordable housing supply and concludes that addressing the Syrian housing deficit requires modification of structural policies, principles and strategies of government intervention to foster collaboration between public and private sectors.
7

Leadership style, organisational culture and disputes in public construction

Alkhamali, Khaled Salem H. January 2014 (has links)
The increasing occurrence of construction disputes has compounded the fragmentation, complexity and adversarial nature of the construction industry. Disputes are associated with high cost, delays, low quality and even the destruction of important relationships among project parties that have taken long years to build and disputes have become ‘the rule rather than the exception’. Despite considerable attempts in literature towards dispute minimization in construction projects, very few studies have addressed the roots behind the occurrence of disputes. Leadership and organisational culture are key influential factors in the construction industry. Effective project leaders should, not only achieve the goals and objectives of the organisations they lead, but also, minimize conflicts and disputes. Also by instilling strong organisational culture, construction organisations can control dispute to minimum levels. Therefore, this study aims to draw research attention toward the core of disputes by providing theoretical insight and empirical investigation concerning the roots of this problem. A framework is presented to minimize disputes in public organisations of construction. The mixed methodology adopted includes a survey conducted to investigate the current practice and semi-structured interviews to explore best practice that combined to form a foundation for the framework that assess leaders and organisations to minimize construction disputes. The findings revealed that among the most significant dispute causes are: delay by the contractor, lack of team spirit, slow contractor response, poor communication, unrealistic tendering, inadequate contractor selection, unforeseen site conditions and inadequate site supervision. Significant correlations were noted between transformational leadership and the most significant dispute causes. Also significant association was indicated between clan culture and disputes. Emerging from the study is that transformational leadership and clan culture appear to be the most suitable leadership style and organisational culture, respectively, in public construction organisations (owner organisations) that help minimize disputes with contractors.
8

Effective stakeholder engagement in variation order management at the design stage of public sector construction projects in Saudi Arabia

Alsuliman, Jawad Ali January 2014 (has links)
Variation orders affect the progress of any construction project and can be one of the main factors which may cause failure in delivering a project successfully. It is relatively difficult to deliver a project without any variation orders, which are most likely to occur at the design stage. Variation orders are complex in nature, as they involve the key stakeholders, together with a lot of information that needs to be requested, sent, checked, corrected, approved, clarified, transmitted or submitted, among many other processe. This research aims to develop a model that better manages variation orders in Saudi public construction projects in the design stage by engaging the stakeholders effectively in the process of the variation order management, to save the management time for the variation, improve the communication and relationships among stakeholders and avoid disputes and conflicts. The methodology used to achieve the research aim, influenced by the pragmatic views of the researcher, combined several methods. A series of exploratory interviews investigated the current practice of variation order management in Saudi public construction projects, with its strengths and weaknesses. Then, a questionnaire survey measured the level of power and interest of the different stakeholders in order to develop a model for best practice. Finally, focus group sessions validated the performance and concept of the developed model. The findings indicate that there are currently no formalised approaches to the management of variation orders at the design stage. In addition, there is a general lack of knowledge about managing variation orders. However, the conceptual model of common practice, based on these responses, can be divided into six main stages: identifying the variation order, analysing and evaluating variation orders, estimation, approval, implementation and documentation. Furthermore, the findings reveal a need to develop an appropriate variation order management system in the Saudi construction industry, due to the present lack of stakeholder engagement. A model for best practice of variation order management was then developed. The developed model determines the levels of power and interest, location and position for each stakeholder involved in the process of variation order management. The outcomes of the validation workshop were very positive from the participants. However, the participants put forward some recommendations, which were applied in the final version of the model.
9

Assessing the role of domestic phosphorus emissions in the human phosphorus footprint

Brownlie, Will January 2014 (has links)
Societal phosphorus (P) use is unsustainable; P is vital for food security and its increase in the ecosphere is the single greatest cause of water quality degradation on the planet. The following thesis focuses on the role domestic P emissions play in the human P cycle with an aim to support management in reducing the individual P footprint. Measurement of the P composition of private sewage system (PSS) effluent was used to assess domestic P emissions from properties located within the Loch Leven catchment, in East Scotland, UK. This thesis shows PSS treatment type (i.e. level of additional treatment further to a single settling tank) does not reduce effluent P concentration, challenging the efficacy of policies aiming to reduce P pollution from PSS by technological solutions. Using a questionnaire, assessment of domestic and PSS maintenance behaviours of 156 PSS users indicated reductions in P emissions may be achieved through behavioural change. To understand the impact of behaviour on the human P footprint, a novel method using 31P nuclear magnetic resonance (NMR) spectroscopy was successfully developed to identify P compounds related to human behaviour (e.g. washing machine use) in PSS effluent. An assessment of the impact of behaviours on the human P footprint of ten individual households was conducted. Thesis findings conclude PSS desludging reduces concentrations of orthophosphate in PSS effluent; 85% of the variation in total soluble P in PSS effluent can be explained by ‘desludging frequency’ and ‘washing machine use’. Furthermore, PSS users feel responsible for correctly maintaining their PSS, but are potentially not maintaining them effectively or have poorly installed or inadequate systems, and do not know how to reduce domestic P emissions. A need for better public education on PSS maintenance and how to reduce domestic P emissions is required. This work highlights a critical need to integrate social sciences with natural sciences to tackle unsustainable P use.
10

A user-centered approach to road design : blending distributed situation awareness with self-explaining roads

Chowdhury, Ipshita January 2014 (has links)
Driving is a complex dynamic task. As the car driver drives along a route they have to adjust their driving technique in accordance with the traffic level, infrastructure and environment around them. The amount of information in the environment would be overwhelming were it not for the presence of stored mental templates, accumulated through training and experience, which become active when certain features are encountered. Problems occur when the environment triggers the incorrect templates, or fails to trigger the correct templates. Problems like these can be overcome by adopting a “self-explaining” (SER) approach to road design. That is to say, purposefully designed roads which trigger correct behaviour. A concept which can help improve the theoretical robustness of the SER approach is Situation Awareness (SA). SA describes how the environment and mental templates work together to ensure drivers remain coupled to the dynamics of their situation. It is a widely researched concept in the field of Human Factors but not in the domain of Self-Explaining Roads (SER), despite the very obvious conceptual overlaps. This thesis, for the first time, blends the two approaches, SA and SER, together. From this the ability to extract cognitively salient features and ability to enhance driving behaviour and their effects on driving behaviour are sufficiently enhanced. After establishing SA as critical to driving through literature review the experiment phase started with determining the source of driver SA. Road environment was found to be of utmost importance for feeding into driver SA. This was also confirmed with the results of the on-road exploratory study. The success of the exploratory study led to large scale naturalistic study. It provided data on driver mental workload, subjective situation awareness, speed profile and endemic feature. Endemic features are unique characteristics of a road which make a road what it is. It was found that not all endemic features contribute to SA of a road system. Therefore through social network analysis list of cognitive salient features were derived. It is these cognitive salient features which hold compatible SA and facilitate SA transaction in a road system. These features were found to reduce speed variance among drivers on a road. The thesis ends by proposing a ‘road drivability tool’ which can predict potentially dangerous zones. Overall, the findings contribute to new imaginative ways road design in order to maximize safety and efficiency.

Page generated in 0.0155 seconds