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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.
161

INSTRUCTIONAL MANAGEMENT, ENVIRONMENTAL VARIABLES AND STUDENT ACHIEVEMENT (PATH ANALYSIS).

DAVID, ELIZABETH LINDLEY., DAVID, ELIZABETH LINDLEY. January 1984 (has links)
The ultimate goal of education is to facilitate student learning and achievement. Instructional management offers one means of evaluating the impact of various teaching behaviors on student learning. Environmental variables also interact with instructional management variables to influence teacher behavior and student learning. It was the purpose of this study to evaluate the influence of instructional management and environmental variables on student achievement utilizing a causal model. Subjects included 430 elementary and junior high school students in grades four through eight. Multiple regression was utilized in establishing the path coefficients and standard errors of the explanatory variables effect on student achievement. Results of this study suggest that teacher education, teacher knowledge, student grade, classroom complexity and classroom mobility account for a large proportion of the total variance in the path model. Master's level teachers significantly affect both the teacher's knowledge of the instructional content mastered by the student and the student's achievement. The grade level of the student significantly affects the student's achievement. The teacher's knowledge affects student achievement at the p < .001 level.
162

Sedimentology, facies architecture and hydrocarbon potential of the Merrimelia Formation (glacial Permo-Carboniferous), Southern Cooper Basin, South Australia

Chaney, Alistair John January 1990 (has links)
Sedimentological analysis of cored sections within the Merrimelia Formation (basal Gidgealpa Group, Cooper Basin, South Australia) reveals a complex glacigenic environment, including glaciolacustrine, deltaic, shorezone, fluvial, aeolian and other associated terrestrial facies (over 20 different facies have been identified). These facies are observed within terminoglacial and proglacial environments and interfinger laterally and vertically constantly throughout the Merrimelia Formation, exhibiting rapid environment change related to the position of ice sheet. Detailed sedimentological and petrographical (Cubitt 1998) analysis suggests that Tirrawarra sandstone-type sandstones facies belong within the Merrimelia depositional realm. Provenance data (Cubitt 1998) indicates that the lithic component of the Tirrawarra Sandstone (sensu stricto), is sourced from reworked Merrimelia coeval depositional facies. It is proposed that the fluvial sandstones of the Merrimelia Formation are part of the same fluvial deposystem as the Tirrawarra Sandstone (sensu stricto) as the two sandstone sequences are the natural progression of coarsening sediment as more detritus was released from melting glaciers during deglaciation. It is suggested that there no longer remain any sedimentological, stratigraphical or petrographical (Cubitt 1998) reasons why the Tirrawarra Sandstone (sensu stricto) and the Merrimelia Formation glaciofluvial sandstones should not be grouped together as Tirrawarra-type facies within the Merrimelia glacigenic domain. Facies architecture across the basin on both field and basin wide scales has identified two regional lacustrine episodes, both of which are followed by a period of lacustrine basin clastic infill. Such cycles represent ice advance and retreat, allowing two deglaciation phases and one ice advance phase to be identified.
163

The effects of state's construction procurement policy implementation on the outcome of local construction projects : the Libyan case

El-Hasia, Atif Mailoud January 2005 (has links)
The successful execution of public construction projects and keeping them within estimated cost and prescribed schedules, quality and satisfying policy goals depend on a methodology that requires sound engineering and managerial judgment. This problem is more evident in the public traditional or adversarial type of contracts in which the contract is awarded to the lowest bidder. Construction procurement policy of public projects has been utilised by many countries as an important tool for achieving economic, social, political and other objectives in developing all aspects of change in the construction industry. Although the construction industry in Libya has suffered ever since the UN sanctions, recent events in the region coupled with the restructuring of the economy, lifting the sanctions and re-establishing new relations with the developed world and global free trade organisations, and attracting foreign investments are expected to yield an unprecedented growth in the construction activities. The Libyan infrastructure is in desperate need for development projects in many areas, especially in the fields of water collection and distribution, tourism and housing. As a result, an unprecedented number of projects are currently under planning and contract awarding stages, which poses as a potentially effective opportunity to drive for change in the construction industry and beyond. This research is an insight of the issue of how construction procurement policies are made and how they affect the outcome of a local public construction project in the current Libyan setting. This was achieved by dividing the first theoretical part in to three pillars or elements of research concerned with, Public policy in the context of construction procurement; Public Sector construction procurement and Public Sector Projects Outcome to build a solid platform of a conceptual knowledge before embarking on a case study investigation to give the required realistic background to the scientific research. Three case studies were selected based upon criteria drawn from the literature review. An intra and cross case study analysis were carried out based mainly on projects' a review and analysis of projects' documentation, but supported by questionnaires and an interviews for each project case study, which enabled a process of contrast comparison, replication and interpretation of findings. It was found that public construction procurement policy in the Libyan local context lacked clarity in defining policy goals. Moreover, construction procurement is perceived as a contract strategy or an arrangement, where by emphasis on the technical aspect was far greater than emphasis on other related policy as a drive-for-change aspects. The policy of restricting the form of public projects contracts made for hard to local public clients to embrace other procurement systems, which might have been more beneficial to the outcome of projects in terms of satisfying policy goals. It appeared that State bodies are more concerned with the administrative side of these projects. Technical and project managerial aspects are usually left for their consultants, either public or private. This caused a serious detachment of control and therefore difficulties and shortcomings in using the construction procurement of local public projects as a policy tool. The main findings of the analysis were based on taxonomy of documentary data collected in the case studies, which assisted in generating conclusions linking back to the theory of the three research elements mentioned above. Finally recommendations along the lines of enhancing transparency, the communication process, the need for a comprehensive State guidelines and the need for vocational education and training to participating State bodies were presented as an attempt to inform and possibly assist academics and Libyan policy makers to achieve positive and fruitful goals in local construction projects through good construction procurement policy making and implementation.
164

Terminopolis or terminal institution? : a sociological examination of the institutionalised airport terminal

Coulton, J. A. January 2014 (has links)
The airport terminal is becoming an increasingly ‘taken for granted’ part of many peoples’ lives. As air travel becomes less expensive, more and more individuals are choosing to travel for both business and pleasure, and the airport has become a site of increasing interest to scholars from a variety of academic disciplines. Sociologists, geographers and anthropologists have offered a range of perspectives on the spatial nature of the airport, ranging from the ‘transitional space’ described by Gottdiener (2001), to Auge’s (1995) ‘non-place’, free and empty of power and social relationships. The sociological foundation for this thesis however, stems from the work of Erving Goffman, and specifically his examination of the total institution. In an effort to capture the institutional nature of the airport terminal, the study used observation, semi-structured interviews and video and audio recordings during fieldwork at airport terminals across the globe. Specific conceptualisations of the airport as a city, shopping mall, theme park and non-place are explored through existing literature and empirical study, and are measured against the institutional backdrop of the practices and activities of the places themselves. The author concludes that airport terminal buildings are not the conceptualisations they are often cited as being. They are however sociologically significant spaces because of their design and use in the era of increased globalisation, security, control and uncertainty, where people management and control is seen as a vital function, and where the conversion of customers into compliant docile bodies is key to minimising risk and maximising profits.
165

Quantitative tool for measuring safety culture on busy construction sites in Great Britain

Dixon, W. S. January 2014 (has links)
This thesis is aimed at developing an academically robust, cost effective tool / procedure for measuring safety culture that is easily administered on a busy construction site in Great Britain. This researcher works as a safety manager on construction sites and is typically employed on multi-million pound new build projects for blue-chip clients. These sites typically employ between 1-3,000 workers. Keeping workers safe is challenging and important, not only from the legal and ethical perspectives but also to ensure the companies reputations. To this end all of the companies and clients that this researcher has worked for in the last 15 years have been keen and vocal in their attempts to improve the safety culture on site. The researcher has witnessed large sums of money being spent in an attempt to make such improvements. Typically, companies wish to see tangible results after having invested money in order to facilitate change or improvements. Investing money to improve the site safety culture should be no different. This is where the difficulties arise and where a gap in knowledge has been identified by this research.
166

Comparisons on the perceptions of reproduced urban soundfields and urban soundscapes : a mixed model approach

Ackroyd, T. A. January 2015 (has links)
Soundfield reproduction has a vast array of applications, yet the ecological validity – and external validity – has been little researched beyond the narrow limits of the physical approach. This mixed model research explored the differing perception of reproduced urban soundfields and urban soundscapes. The methodology analysed the influences of: auralisation technique; soundscape; place affordances; time; space; and memory – subject agency and expertise. Three methods of data collection and analysis were employed: a semantic differential analysis and two psycholinguistic methods – one existing and one novel. The semantic differentials’ soundscape dimensions of the public’s response from in situ listening were replicated by participants’ responses from ambisonic reproduction but not binaural. A generalised soundscape dimension model was proposed that integrates the structural model of appraisal theory with the interpretation of motivation-affordance fit and mediation dimensions. Different soundscapes were evaluated differently and stimulated differing processes of perception, which in turn effected reproducibility. A focus group was used as well as members of the public and laboratory participants. It was found that experts responded more in terms of source identification. Existing methods found no significant difference between in situ and ambisonic listening. The novel method found the ambisonic soundfield was described in terms of objects in motion or sound objects whilst the binaural soundfield and in situ soundscape were described in terms of sources or activity. As an assessment of external validity, the novel psycholinguistic method found that binaural reproduction held validity over ambisonic reproduction. An in situ real-time binaural reproduction test sought to isolate the ‘electroacoustic ear’ – the findings were consolidated and discussed in terms of embodiment and ventriloquism. The novel psycholinguistic analysis provided a more accurate representation of the cognitive process of soundscape perception and is offered as a tool for the external validity assessment of urban soundfield reproduction.
167

Quantifying Himalayan glacier change from the 1960s to early 2000s, using corona, glims and aster geospatial data

Wilson, R. January 2015 (has links)
Since reaching their LIAMs, Himalayan glaciers have generally undergone a period of retreat, evident from large moraines left at former ice limits. Currently, however, detailed assessments of Himalayan glacier fluctuations over the past century are limited and fail to compare spatially or temporally to records available in Central Europe, North America and Scandinavia. Consequently, the variability and magnitude of glacial change across the Himalayas, which is a key indicator of climatic change in this region, is yet to be fully understood. Against a background of poor data availability, Corona imagery and historic GLIMS glacier outlines now offer an opportunity to assess glacier extent for regions of the Himalayas pre-1980. Corona imagery, acquired by a US space-borne reconnaissance mission operational from 1960 to 1970, represents a particularly unique dataset offering high resolution imagery (~1.8 m) with stereo-scopic capabilities. Utilising Corona imagery, there is an opportunity to produce detailed maps of Himalayan glacier extent and extract ice surface elevation estimations, in some instances, for the first time. Despite having been de-classified in 1995, the use of Corona data in the Himalayas has been neglected, mainly because of orthorectification challenges related to its unique geometric distortions. Hence, there remains a need to develop a low cost and easily replicable method of accurately orthorectifying Corona imagery enabling its use as a large-scale glacier mapping tool in the Himalayas. In response to this need, Corona images are orthorectified in this study through the use of: (1) a non-metric photogrammetry approach; and (2) horizontal and vertical reference data acquired from ortho-ASTER imagery and the freely available ASTER GDEM. By comparing glacier measurements derived from Corona imagery, GLIMS data and more contemporary ASTER data, changes in glacier area, length and in some instances volume, between the 1960/70s and early 2000s, were quantified for glaciers selected within four study areas located in Uttarakhand, India and Central Nepal. Importantly, this cross-regional glacier change dataset both complements and enhances current Himalayan records. Most notably, results indicate that glaciers selected in the Bhagirathi and Pindar/Kali basins, Uttarakhand, reduced in area by a relatively small 7.97±0.29% and 7.54±0.26%, respectively. Contrastingly, glaciers selected in the more easterly located Seti and Trisula basins reduced in area by 29.78±0.2% and 50.55±0.08%, respectively. Comparisons of Corona DEM (derived from Corona stereo-pairs) and ASTER Global DEM elevations at the terminus regions of four glaciers revealed extensive surface lowering, ranging from 87±27 m to 142±27 m. For Corona processing, the methods applied were shown to orthorectify Corona images to an accuracy that allows comparable glacier outlines to be delineated, further demonstrating the mapping potential of this dataset. However, for Corona DEM extraction, the use of ASTER spatial control data was shown to be inadequate and the presence of large vertical errors in the DEMs generated hindered the measurement of glacier volume change. For this purpose, it is therefore recommended that the methods developed are tested with the use of very high resolution spatial control data.
168

A contingency model for facilities management outsourcing relationships (CORE) in the Hong Kong higher education sector : an exploratory model for linking FM outsourcing performance to higher education business performance

Lok, K. L. January 2013 (has links)
The focus of study is to determine the relationships between clients and FM service providers by developing a yardstick for measuring and appraising the relationships in main FM outsourcing contracts in the higher education sector of Hong Kong. In this study, “outsourcing relationships” are defined as “the extent to which an FM outsourcing contract facilitates effective ownership or control of FM assets, and enhances the competitive positioning and long-term strategies of the outsourced FM portfolio whilst the client’s requirements are met”. The most practical and successful approach for improving FM outsourcing relationships reported in the literature is a model based on quantitative assessment. A review of the literature suggests that the Four Outsourcing Relationship Types (FORT) model, used in the information technology industry, can be adapted for use in FM outsourcing. The data from two Delphi surveys and two questionnaire surveys, administered to 38 clients and 34 FM service providers, were used to build the proposed Contingency Outsourcing Relationships (CORE) model. The data analyses included the Kruskal-Wallis test, the Mann-Whitney U test and a Multi-nominal logistic regression. The Analytical Hierarchy Process and two focus group meetings were also used to develop the model. The CORE model can be used to assess the four categories of outsourcing relationships by focusing on the four main FM outsourcing service contracts in Hong Kong’s higher education sector: (i) building maintenance; (ii) security; (iii) cleaning; and (iv) catering. Other FM outsourcing service contracts are not covered by the CORE model. In the model, the combination of two different outsourcing relationship components or dimensions contributes to an outsourcing relationship type. In conclusion, the empirical investigation reveals a significant relationship between FM outsourcing relationship types and services in the context of Hong Kong’s higher education sector. Clients and service providers have indicated that applying the FM outsourcing relationship types improves the quality of the services. The findings indicate a match in the preference for the extent of outsourcing relationship dimensions on the ownership and control of service provider involvement on current outsourcing contracts for building maintenance, cleaning and catering in Hong Kong’s higher education FM industry. This study also discusses that the importance of matching demand and supply of FM services plays a major role in the FM outsourcing success.
169

A viable infrastructure delivery systems model for achieving socio-economic benefits in the Nigerian oil and gas industry

Awuzie, Bankole Osita January 2014 (has links)
In apparent realisation of the place of procurement in driving the implementation of socio-economic policies, successive governments across the globe are increasingly demanding more from suppliers as it pertains to the delivery of socio-economic benefits. This has resulted in a significant shift in what constitutes success in the respective projects which they commission; from factors related to the ‘iron triangle’ to contributions of the project to the growth of the local economy. Policies such as the Social Value Act, and the Nigerian Oil and Gas Industry Content Development Act (NOGICDA) in the United Kingdom and Nigeria respectively readily come to mind. Judging by the plethora of literature bemoaning the prevailing high poverty and unemployment rates in developing and resource-rich countries such as Nigeria; it would appear that the implementation of such policies has failed to deliver the expected outcomes. This opinion is affirmed by several studies which point to the possibility of implementation failure in such countries. Surprisingly, none of these studies has made any attempt to explore the manner in which implementation is organised and governed. Obviously, the seeming absence of a veritable platform for implementation analysis constitutes an immense challenge to effective analysis. As a result of this, previous investigators appear to have failed to properly tackle this imbroglio from a holistic and systemic perspective. To bridge this gap, this qualitative study embarked upon an evaluation of the implementation process using the NOGICD Act as an exemplar. The failure of the nation’s economic sectors to achieve sufficient backward linkage with the oil and gas industry, as evidenced by the reported failure of local suppliers to gain entry into the supply chains of major infrastructure projects contributed to this choice. The Viable Systems and Temporary Multi-Organisations theoretical lenses were applied in the conceptualisation of the inherent complex interorganisational relationships thus resulting in the development of a Viable Infrastructure Delivery Systems Model (VIDM); a model premised on systemic and cybernetic principles. The VIDM was then applied in conceptualising and evaluating the extant interorganisational relationships within selected infrastructure delivery system case studies in Nigeria and the United Kingdom depicting the multi-case study nature of the study. A mixture of unstructured, semi-structured, and structured interviews were employed at various stages of the study. Also, policy and publicly available contract documents were explored. Subsequently, the emergent data was qualitatively analysed using pre-set themes, with NVivo software. The findings obtained were used to test various propositions on a within-case and cross-case basis. It was observed that the VIDM was better positioned to conceptualise and evaluate the various interorganisational interactions within infrastructure delivery systems and how they influence implementation success. Furthermore, the application of the VIDM within the selected cases enabled the discovery of various issues within the IDS capable of undermining successful implementation such as non-alignment of goals within the IDS, excessive government interference, lack of appropriate criteria for measurement of benefits and cognition-related issues. It is expected that the VIDM would be used by implementation advisors for conceptualising and evaluating interorganisational relationships during policy or strategy implementation cycles and/or for (re)designing implementation processes for viability within the Nigerian oil and gas industry.
170

Effects of Transformations of Ag and CuO Nanoparticles on Their Fate in Freshwater Wetland Sediments and Plants

Stegemeier, John Peter 01 September 2016 (has links)
Engineered nanomaterials (ENMs) are increasing becoming incorporated into consumer products to imbue remarkable physical and chemical properties. The increased use of these ENMs leads to a growing need to understand the environmental fate of ENMs after release. Many ENMs, including Ag and Cu ENMs, have the potential to undergo complex physical and chemical transformations which impact their toxicity, solubility and fate in the environment. There is a lack of research characterizing the transformation rate and understanding how these transformations affect interactions with organisms and the ultimate environmental fate. The first objective of this thesis was to understand how transformations of Ag ENMs affect the uptake, distribution and speciation of these materials in plants. Terrestrial (alfalfa, Medicago sativa) and an aquatic (duckweed, Landoltia punctate) plant species were exposed hydroponically to as manufactured (“pristine”) Ag0-NPs and more environmentally relevant (“transformed”) Ag2S NPs. The uptake, spatial distribution and speciation of Ag were analyzed using synchrotron based X-ray Absorption Spectroscopy (XAS) techniques to provide mechanistic insights into the uptake of these ENMs. The reduced solubility and reactivity of Ag2S ENMs was expected to prevent plants from solubilizing these particles and only allow for direct uptake of particles. For the more soluble Ag species, the absorption of Ag+ ions was expected to be primarily the mechanism of Ag uptake. Although the total Ag associated with the plants was similar, the Ag distribution in the roots was dramatically different. The transformed ENMs (Ag2S) appeared to be taken into the plant tissue as sulfidized ENMs. The pristine Ag0 ENMs were found to partially dissolve and incorporate into the plant tissue as both dissolved Ag and Ag0-NPs. The fact that ENMs readily attach onto plant tissue regardless of speciation and solubility suggests that exposure to ENMs may be controlled by factors affecting attachment to root surfaces. However, internalization of Ag appears to be affected by solubility. The second objective was to characterize the impact of transformations of Ag and Cu-based ENMs on the distribution, speciation and fate of these materials in subaquatic sediments and the aquatic plant, E. Densa in a simulated emergent freshwater wetland using large-scale mesocosms. The exposure of pristine (Ag0 and CuO) ENMs and their transformed analogues (Ag2S and CuS) was compared to an ionic control (Cu(NO3)2) to determine if nanoparticulate species of metals were distributed differently than their dissolved counterparts. The metal speciation was determined using XAS to elucidate relative timescales of transformations. The pristine ENMs were expected to rapidly transform into their more stable sulfidized species and the uptake of Ag and Cu were expected to depend on the solubility of the ENMs. Transformations of the pristine ENMs were found to be rapid (weeks) in the surficial sediment, but slower (months) in the aquatic plant tissue. The uptake of ENMs coupled with the slow transformation in the aquatic plant tissue suggests ENMs persist longer than the timescales measured in sediments. This knowledge enables better risk forecasting for ENMs exposed to aquatic organisms and informs toxicity testing to ensure correct forms of ENMs are examined. This thesis provided several novel contributions to the understanding of how transformations of ENMs affect their interactions with plants and their fate in real complex environments. Mechanistic insights into the attachment and uptake of ENMs into plant tissues were identified suggesting two predominant uptake pathways. Relative timescales of ENM transformations in freshwater wetland sediments and plant tissue provided suggests plants can slow transformations and allow labile ENMs to persist longer than assumed.

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