• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 5087
  • 3497
  • 2139
  • 1150
  • 1110
  • 390
  • 123
  • 110
  • 106
  • 105
  • 88
  • 81
  • 76
  • 76
  • 60
  • Tagged with
  • 16809
  • 2611
  • 1975
  • 1798
  • 1765
  • 1453
  • 1439
  • 1438
  • 1389
  • 1275
  • 1194
  • 1165
  • 1062
  • 904
  • 842
  • 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.
151

Application of a Green Roof on the College of Architecture, Planning, and Landscape Architecture

Horn, Patricia January 2016 (has links)
Sustainable Built Environments Senior Capstone Project / In the United States, commercial rooftops are too often an afterthought, serving only to house HVAC systems and other utilitarian building components. Rooftops are the most underutilized valuable spaces in buildings. They comprise a great deal of real estate that could help boost a building’s energy efficiency, aesthetics, and even the wellness of occupants. Buildings are the leading contributors to energy consumption in the country, and implementing green roofs could significantly mitigate this energy use, so costly to society in so many ways. This proposal studies the benefits of implementing a green roof on the College of Architecture, Planning, and Landscape Architecture (CAPLA) in Tucson, Arizona. Extensive research was conducted on the implementation of a green roof in this hot arid region, as well as a survey among a pool of 50 occupants. The conclusions drawn: a green roof would be utilized by occupants, and would bring about benefits including cleaner air, an expanded roof lifespan, and reduced heat island effect. Conclusions also demonstrate that the cost of implementing a green roof might not be offset by energy savings alone, but when considering the benefits and costs to society, a green roof ultimately proves beneficial economically as well.
152

The Application of Porous Concrete

Curtis, Kyle January 2016 (has links)
Sustainable Built Environments Senior Capstone Project / The southwest region of the United States is stressed for potable water and needs to positively utilize its current water resource. With the urban environment being mostly made up of concrete, it is now crucial to assess its development and application. The concrete used today is a mixture of cement, water and aggregates and is not permeable. The non-permeable property of common concrete prevents natural water absorption by the earth and greatly inhibits water to percolate back into the local water table. As concrete, has developed, porous concrete has been discovered. Porous concrete or pervious pavement is made in the same way that concrete is made with cement, aggregate, and water, but the aggregate used in porous concrete creates pores that allow water to pass through. By allowing water to pass through concrete, urban development will result in greater ground water recharge. As global warming intensifies weather patterns across the planet, Tucson, Arizona will experience heavier rainfall seasons. As the world’s climate changes, Tucson will experience heavier monsoon rain fall events. With heavier rain fall events urban flooding will become more of an issue. Grey infrastructure is needed to manage flooding caused by heavy rain fall. Porous concrete can be used as an effective way to manage storm water. This capstone has undertaken an extensive range of literature reviews to identify where porous concrete can be used for storm water harvesting. The literature reviews range from climate change to the benefits of storm water harvesting. Porous concrete allows storm water to infiltrate through it and back into the local aquifer and directs storm water into retention ponds for treatment and reuse. Porous concrete is a low impact development (LID) building material, which will turn urban development into Sustainable development. Porous concrete if used correctly for storm water harvesting can reduce potable water stress, reduce pollutants found in local waters, and reduce the strain on current storm drains. The required maintenance associated with porous concrete is minimal and not costly, therefore will be only briefly explained throughout this research. While porous concrete has a wide range of benefits ranging from water percolation to the reduction of the heat island effect, this paper will focus on its use as a means of storm water harvesting.
153

An integrated approach to environmental education: a case study

du Preez, NP, Mohr-Swart, M 01 January 2004 (has links)
Abstract In 1994, the Executive Management Committee (EMC) of Technikon Pretoria took a strategic decision to develop educational programmes in environmental management and sustainable development. The EMC also decided to integrate these programmes with the development and implementation of an environmental management policy for Technikon Pretoria. This paper describes, in the form of a case study, the project embarked upon, which brings together the development and implementation of the curriculum, research and development, management processes for sustainability, community service and national and international cooperation. The paper discusses successes and failures, and the significant lessons that could be learnt from the experience.
154

Die verwantskap tussen prestasiemotivering en organisasieklimaat

17 November 2014 (has links)
M.Com. / Please refer to full text to view abstract
155

The use of sound intensity for characterisation of reflected energy in small rooms

Romero Perez, J. January 2014 (has links)
The sound field in rooms of small dimensions used for music reproduction is characteristically different from that found in larger rooms for music performance such as auditoria. Key differences between small critical listening spaces and large auditoria are the vastly different ranges of energy decay, 100 ms for the former and up to 8 s for the latter, and its directional behaviour, typically non-diffuse for the former and approximating a diffuse field for the latter. Despite these substantial differences, most of the metrics developed to describe the sound field in large spaces are evoked to quantify the performance of small rooms. This project focuses on developing measurement methods to characterise temporal and spatial qualities of sound in small rooms. A number of methods based on currently available acoustic probes have been developed. The implementation requisites and accuracy for each method has been quantified. Factors such as direction, time of arrival and strength of reflections have been extracted using signal analysis techniques based on the active instantaneous intensity and short-time Fourier transform. These factors are subsequently mapped to allow a description of their evolution through the energy decay in the room for a given measurement location. The best performing system, based on the use of one-dimensional p-p intensity probe mounted in a custom cradle, achieves a minimum overall mean error of 0.226 degrees and 2.971 degrees for the direct sound and first reflection respectively, which is near or below the measured human minimum audible angle (MAA). The method developed has direct applications in the quantification of small room acoustic sound fields for critical listening purposes.
156

A comparative study of sediment trace metal levels in upland lakes in the southern and northern Carpathians of Romania

Akinyemi, O. F. January 2013 (has links)
The Carpathian Mountains in Romania hold around 150-200 glacial lakes and traverse a region where there are considerable environmental concerns. Despite a long tradition of palaeoecological study in the region, to date relatively little has been published on the alteration of their sediment characteristics due to recent human-induced environmental impacts. This research project has investigated the physical characteristics, the mineral magnetic properties and the trace metal levels of sediment cores from ten selected lakes in the southern and northern Carpathians of Romania in order to evaluate the possibility of using these lakes’ sediment as records of recent human impacts and, in particular, trace metal deposition. Laboratory analysis has included sediment bulk density measurements, loss-on-ignition and laser diffraction based particle size determination, environmental magnetism and geochemical (ICP-OES) analysis. A single core from one of the south lakes (Lacul Capra) was radiometrically dated. There were distinct variations in catchment and lake area, the ratio of catchment area to lake size and in lake depth between both regions. The physical characteristics of the lake sediments demonstrated similar trends in their down core profiles in both regions, although the lakes from the south demonstrated a larger particle size range than those in the north. The environmental magnetism of the sediment cores demonstrated common characteristics in surface or near surface peaks magnetic concentration, but there were variations in the magnitude of the concentrations between both regions. The surface increase in concentrations indicated the influence of the atmospheric deposition of particulate deposition associated with fossil fuel combustion and vehicle emissions, but it may also be influenced by microbiological activities within the lakes’ sediment. The geochemical analysis (EFs and down-core profiles) showed that the same trends in metal concentration were repeated across the lakes in both regions, but the south lakes displayed higher peak in Pb and Zn concentrations, than were found in the north lakes. The research project has demonstrated the likely influence of atmospheric particulate deposition on the sediments of the lakes from both regions and it has demonstrated spatial and temporal variations in trace metal levels in the lake sediments. It has thereby provided a preliminary database and an overview of palaeolimnological information in two regions of the Romanian Carpathians. Thus, it provides an addition to the records of recent pollution in Romania and a gateway to further investigations in the area of recent palaeoenvironmental change in this region.
157

The Art of Persuasion: Self-Esteem, Message Framing, and the Persuasiveness of Prosocial Messages

He, Theresa (Huan) 24 December 2015 (has links)
Our planet currently faces an environmental crisis. Thus, understanding how to persuade people to donate their time and money to environmental organizations has become an ever-pressing concern. Prior research has shown that personality factors such as the behavioural inhibition system (BIS) and the behavioural activation system (BAS) along with promotion and prevention orientations can interact with message frame (i.e, gain- versus loss-framing) to induce regulatory or affective fit, thereby increasing the persuasiveness of the message (e.g. Higgins, 2000; Updegraff, Sherman, Luyster, & Mann, 2007). I propose and test the hypothesis that self-esteem will also interact with message frame to increase persuasion, even when BIS/BAS and promotion/prevention are controlled. I test this hypothesis in two experiments (Ns = 828 and 1614). In each study, participants completed a series of questionnaires assessing BIS/BAS, promotion/prevention, and self-esteem and then read either a gain- or loss-framed environmental message. Then participants completed a memory test concerning the message content. Finally, they completed a donation task in which they apportioned a lump sum of money to five different charities, including one environmental charity. Contrary to my hypotheses, there was no interaction between self-esteem and message frame in either study. However, participants in the loss-framed condition donated more money to the environmental charity than did participants in the gain-framed condition, and this difference was explained by participants' greater memory for the loss-framed message. Moreover, the second experiment demonstrated that participants also reported stronger intentions to behave pro-environmentally when they had donated money to the environmental charity. Thus it appears that loss-framed messages are more effective at persuading people to donate time and money to environmental causes. Due to the paucity and mixed-results of research on gain- and loss-framing in the environmental field, my research can help contribute to the few studies on this topic. The practical application of these results may prove useful to environmental charities and organizations. / Graduate / 2017-12-16 / 0451
158

The use of molecular tools for Pan-Trypanosoma analysis and epigenetics of the host

Ideozu, E. J. January 2015 (has links)
Trypanosomes are a major cause of disease and death in both animal and human populations. Resistance or susceptibility to African trypanosomes has been associated with TLR9 gene. Hence, the primary objectives of this study were to apply molecular tools to investigate trypanosome infections in British badgers and Nigerian cattle, and to investigate variation in bovine TLR9 gene in relation to their trypanosome infection status. The ITS Nested PCR method was used to detect trypanosomes in the British badgers and Nigerian cattle. Two novel hemi-nested PCRs targeting two bovine TLR9 CpG Islands were developed to derive genetic and epigenetic DNA sequence data of 72 African bovine samples. Twenty-nine out of 82 badger samples amplified tested positive for trypanosomes (35.4% prevalence). Analysis of sequence data showed the badgers were infected with Trypanosoma (Megatrypanum) pestanai and as expected our phylogenetic analysis shows the badger trypanosome to cluster together with T. pestanai (100% bootstrap support) in the Megatrypanum clade. Ten out of 80 Southern Nigerian cattle were shown to be positive for trypanosomes resulting in a 12.5% prevalence rate. A total of 9 polymorphisms were found in targeted region of bovine TLR9 gene. The study showed no significant association between SNPs and trypanosomiasis (p = <0.05). Our results confirm the methylation of bovine TLR9 gene and identified CpG-SNPs (2256 and 2865) which removes a C-G site and perhaps could alter DNA methylation as potential epigenetic markers for bovine TLR9 gene. Also, it reports the significant correlation between CpG Island SNPs (p = <0.05, all cases), suggesting possession of one Island SNP is a predicting tool for possession of the others. Future work is targeted at publishing papers in peer reviewed journals based on results from these studies.
159

Assessing the quality of low frequency audio reproduction in critical listening spaces

Stephenson, Matthew January 2012 (has links)
The quality of low frequency audio reproduction in small spaces has always been problematic. For some time, methods have been suggested in order to optimise this reproduction. Many such methods have been based upon objective metrics which remain unproven from a subjective perspective. Whilst perception has been studied, this thesis identifies a research gap for more thorough testing. A series of listening tests has been conducted, with virtual rooms auralised and presented over headphones in order to isolate specific modal parameters and allow efficient collection of subjective response from many listening environments. The work presented searches for optimal values and perceptual thresholds of three parameters - modal spacing, density and decay. Results show that optimal spacings and densities may only be defined where assumptions are made which are not valid in realistic listening spaces. Thresholds of modal decay1 have been defined, which are considered valid re- gardless of stimuli or replay level. These are around 0.2 seconds for frequencies above 100Hz, and increase sharply below this point to around 0.85 seconds at 32Hz. Through the testing of these parameters, it is shown that whilst discrimination between two rooms is usually a simple task, this does not reveal the underlying repro- duction quality. The perceived quality of the room response is of great importance, and new experiments assess this quality using a paired comparison method which provides a simpler subjective task than direct scaling methods. A set of descriptors is elicited which can be used to evaluate low frequency audio. These descriptors - articulation, resonance and bass energy - are used to assess the impact of three room parameters on perceived reproduction quality. Room response metrics are also eva- luated for perceived quality. Results reveal that modal decay is a primary indicator of quality, with shorter decays producing rooms with a higher perceived quality of reproduction.
160

An Analysis Of Agricultural Decision-Making For Phosphorus Runoff Reduction In The State Of Vermont

Brown, Bethany 01 January 2016 (has links)
Eutrophication, stimulated by phosphorous (P) runoff from landscapes, compromises water quality and can have long-term impacts on the aesthetics, recreation, property values, and drinkability of bodies of water around the world. In the State of Vermont, efforts are underway to control the amount of P entering Lake Champlain per standards set forth in the Federal Clean Water Act. Agriculture has been identified as a major contributor to excess P in the waterways and will be managed according to Act 64, the Vermont Water Quality Act. The studies presented in this paper will introduce two independent methodologies proposed to aid in evaluating the farmer's willingness to implement pro-environmental practices, (1) determining farmer values towards implementation of best management practices to inform policy, and (2) creating a multifunctional sustainability prioritization scheme for dissemination of Clean Water Fund resources. The Vermont Water Quality Act proposes Required Agricultural Practices (RAP) for agriculture in the State with a limited understanding of what the farming community desires from such a policy. This paper's first article titled, "Determining Farmer Values for Implementing Pro-Environmental Practices," analyzes twenty-four farmers and their associated values towards adopting pro-environmental practices for improved water quality. A hierarchical cluster analysis was used to segment farmers according to their adoption of best management practices on their farms. Further, a one-way analysis of variance (ANOVA) was conducted using dependent functional (quality), functional (price), and emotional, social, conditional, and epistemic variables to understand the variance between the segments. The results from this analysis illuminate farmer values. This information can be used to inform water quality policy, ecosystem service payments, communication strategy, and funding dissemination. The Clean Water Fund was created to support the implementation of water quality initiatives in various sectors throughout the State of Vermont. The resources within the fund are limited; therefore careful prioritization of farms for outreach is essential. In the article titled, "Prioritizing Farms for Subsidies: A Multifunctional Approach," a prioritization methodology is presented using theory from the sustainable multifunctional agriculture literature. The sample includes vegetable, vegetable and meat, meat, and maple producers within the State. The diverse production types included in this study reflects the non-discriminatory—relating to production types—policies in Act 64. The study is limited by the exclusion of the dairy sector. Geographic Information Systems (GIS) software was used to map environmental practices on twelve farm landscapes to generate a spatial representation of environmental stewardship that was then translated into an environmental score. This environmental score was combined with social and economic data to prioritize farms based upon their multifunctional sustainability. This ranking methodology may be useful for the State of Vermont in determining the prioritization of Clean Water Fund resources using farm sustainability measurements.

Page generated in 0.0554 seconds