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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

Barriers and opportunities for implementation of Clean Development Mechanism in South Africa: a case study of Gauteng Municipalities

Ntuli, Princess Ntombifuthi 05 November 2012 (has links)
M.Phil. / Clean Development Mechanism (CDM) can be defined as one of the project-based mechanisms established under the Kyoto protocol mechanism as a supplementary measure to assist Annex 1 parties meet their emission reduction targets through investing in project activities that reduce Greenhouse Gas (GHG) emissions and contribute to sustainable development in Non–Annex 1 countries. These projects reduce GHG emissions and generate credits called Certified Emission Reductions (CERs) that the Annex 1 party can use to meet their emission reduction obligations under the Kyoto Protocol [Curnow & Hodes, 2009]. While countries such as China and India have benefited remarkably from the CDM, African countries (including South Africa (SA)) have failed to maximise the financial benefits offered by this mechanism. Even though South Africa is leading, in terms of the number of registered CDM projects in Africa, it is still lagging far behind other developing regions in this regard. The South African leaders in CDM project development are in the private sector. This research aims to identify the constraints that inhibit large scale implementation of CDM projects by Gauteng Municipalities and to investigate the reasons why South African municipalities are lagging behind the private sector in CDM project development, and identify opportunities for further development of CDM projects. This identification was achieved by compiling a list of known barriers (then investigating these barriers together with a number of other factors that may impact negatively on the CDM market in South Africa) The study was conducted using qualitative research techniques, which utilises methods such as participant observation, in-depth interviews and/or focus groups. Three different groups of respondents were identified: (i) the European CER buyers; (ii) the project developers/ CDM consultants in South Africa; and (iii) the Gauteng municipal officials responsible for CDM project development. A separate questionnaire was compiled for each of the three target groups, with purpose of drawing conclusions about the prevailing status of the South African CDM market from the perspectives of these three different groups. Three previous studies have been conducted to investigate the barriers of implementing CDM in South Africa, examining the problem from various perspectives. Little et al. [2007] conducted a study that focused on the inhibiting and facilitating factors affecting the implementation of CDM by South African industries. Wilson [2007] focused on the barriers against and drivers for the implementation of CDM within the Nelson Mandela Bay Municipality - this study drew conclusions about CDM implementation in municipalities based on the experiences of this single municipality. Winkler and van Es [2007] dealt with the opportunities and constraints of the CDM implementation in energy efficiency projects throughout South Africa.
42

Clean Lighting Leads to Improved Health in Rural Africa: Field Study and Design of a Dirt-Powered Generator

Aiden, Aviva Presser 01 May 2015 (has links)
Two billion people world-wide use kerosene-burning lamps for household lighting. These lamps produce large quantities of soot. In Chapter 2, I describe our field study examining 230 people in rural Uganda. I show that kerosene lamps are a major source of smoke exposure in the developing world, and that replacing such lamps with solar-powered lights reduces indoor soot levels 17-fold, leading to significant improvements in health within months. This finding is particularly notable because respiratory disease is the #1 cause of death in children under 5 worldwide. Because solar cells are a challenge to manufacture in the developing world, I next examined the potential of harvesting electrons from soil-based microbes as a source of clean energy. Such devices are known as microbial fuel cells (MFCs); because soil is available everywhere, MFCs can, in principle, be locally constructed all over the world. In Chapter 3, I describe our exploration of the biology of MFCs, using high-throughput DNA sequencing to demonstrate a role for genus Pseudomonas in energy production. I also examine numerous agricultural products available throughout the developing world to determine whether any could serve as a suitable ‘feed’ for MFC soil. I find that dried animal blood increases MFC energy production 10-fold. In Chapter 4, I describe our design of a modular, stackable MFC, demonstrate that it can be easily constructed in rural Africa, and use it to power lights and to charge a cell phone battery.
43

Performance Comparison of Selective Rake Receivers with CLEAN Algorithms in UWB Systems

Yang, Siang-Yu 26 July 2006 (has links)
The Ultra-Wideband (UWB) channel is a dense multipath channel. The system performance and design complexity issues of selective-Rake receiver (SRake) are studied. Rake receiver has difficulties achieving desired system performance in the dense multipath environment. The main ideas of SRake receiver are to obtain the SNR level on known multipath channel and determine the desired number of Rake fingers. In the implementation of the SRake, the CLEAN algorithm is used in selecting the paths with relatively high energy. We can improve the performance of SRake receiver by increasing the accuracy of path selection. By the property of local maximum peak within the smaller partition, Two-Stage CLEAN algorithm acquires the more accurate delay time of multipath. In order to mitigate the sidelobe effect and noise interference, the key assumption in the Deng¡¦s Modified CLEAN algorithm is that using average amplitude around the considered data change as the criterion to determine if the data value is a true path. In this thesis, we investigate CLEAN, Two-Stage CLEAN and Deng¡¦s Modified CLEAN algorithm in three different systems including UWB-Impulse Radio, Pulse Radar and DS-UWB. From the performance comparison, it can be seen that the Two-Stage CLEAN algorithm that has the highest accuracy of path selection in UWB system.
44

Clean-in-Place på Tate and Lyle Sweden AB / Clean-in-Place at Tate and Lyle Sweden AB

Nilsson, Markus, Frölander, Pontus January 2015 (has links)
This thesis work is about an improvement in Tate and Lyle’s Clean-in-Place system. The thesis investigates how the designs around two machines can be constructed to automate its Clean-in-Place system. Alongside, two step-by-step manuals were created on how the machines should be cleaned. Furthermore a cleaning agent were searched for which eliminates the oat residues that Tate and Lyle faces. The study’s focus was to reduce the cleaning time in their closed systems by automating the cleaning sequences and use a more suitable cleaning agent for their type of residues.   The background to the study can be described as a cleaning problem. Tate and Lyle’s Clean-in-Place system is operated manually and is executed twice a month. The cleaning agents in their current situation is sodium hydroxide and nitric acid which is not adapted for the remaining residues that appear in their equipment piping and edges. The problem arises when the monument remains isn’t properly cleared so the production cannot be resumed since contamination may occur. The equipment is disassembled, cleaned by hand and reassembled before the production can be continued.   The purpose of the thesis work is to find the most advantageous way to clean a decanter centrifuge and a separator. A more suitable cleaning agent are examined as well as the economic benefits that can occur at reduced cleaning time. The work delimited from practical construction and planning for an upgraded system.   The result consists of two step-by-step manuals that specifically describes how the machines should be cleaned with a Clean-in-Place system. Subsequently, two designs were developed around the decanter centrifuge and separator. The designs describe the placement of pipes, valves and pumps as well as suggestions for new pipelines that provide cleaning benefits. Examination of more customized cleaning was done as an experiment in the chemistry department at the School of Engineering in Jönköping. The experiment presented as unsuccessful and wouldn’t be repeated because of optimistic planning. Instead, the result was presented as a Pugh-matrix where four supplements based on similar studies were used. With an automated system and a qualified cleaning the production time could be increased by 9, 7 %. The economic change was presented as an investment calculation. / <p>Vissa bilagan har valt att döljas på grund av sekretesskäl</p>
45

External factors impacting firms marketing strategies : - A study of Swedish clean-tech firms

Hedin, Mattias, Carlbrant, Thérése January 2010 (has links)
It is said that eco innovation is the future of Europe’s competitiveness and by that Swedish companies face an exciting opportunity within the field of clean tech. This industry is expected to continue growing worldwide but Swedish companies still have a low export rate even though they have great potential due to their advanced technology. The purpose of this paper is to study the development of firms marketing strategies regarding product-market scope and differentiation and the impact of external conditions. The study will concentrate on the development of Swedish clean-tech firm’s marketing strategies in the U.S. How the perception of competition is impacting entrant firms’ market strategies has been scrutinized with help from a model developed by the authors based on perception of barriers and incumbent’s market strategies. The findings derived from three case companies claim that there is a relationship between the perception of barriers and incumbent’s market strategies on entrant firms’ market strategy. This implies that relying on advanced technology is not enough to become successful in new markets and that a successful market strategy is dependent on more than the product itself. The entrant firm must consider its situation and its options with help from their knowledge about barriers and incumbent’s market strategies.   Key words: Strategy, clean tech, barriers, product/market scope / Svenska miljöteknikföretags marknadsexpansion
46

Algae biofuels in Texas

Salpekar, Ashwini 13 September 2010 (has links)
Texas – the energy center of the world – is emerging as a pioneer in algae biodiesel research and production. There are a number of reasons for this. Texas is the largest emitter of CO₂ in the country, and efforts are being made to reduce the state's dependence on fossil fuels. Also, algae – robust and promising organisms – need non-arable land, lots of sunlight and brackish/waste water, along with CO₂. Texas has all of these in abundance, plus universities and algae start-ups that are doing crucial R / text
47

External factors impacting firms marketing strategies : - A study of Swedish clean-tech firms

Hedin, Mattias, Carlbrant, Thérése January 2010 (has links)
<p>It is said that eco innovation is the future of Europe’s competitiveness and by that Swedish companies face an exciting opportunity within the field of clean tech. This industry is expected to continue growing worldwide but Swedish companies still have a low export rate even though they have great potential due to their advanced technology. The purpose of this paper is to study the development of firms marketing strategies regarding product-market scope and differentiation and the impact of external conditions. The study will concentrate on the development of Swedish clean-tech firm’s marketing strategies in the U.S.</p><p>How the perception of competition is impacting entrant firms’ market strategies has been scrutinized with help from a model developed by the authors based on perception of barriers and incumbent’s market strategies.</p><p>The findings derived from three case companies claim that there is a relationship between the perception of barriers and incumbent’s market strategies on entrant firms’ market strategy. This implies that relying on advanced technology is not enough to become successful in new markets and that a successful market strategy is dependent on more than the product itself. The entrant firm must consider its situation and its options with help from their knowledge about barriers and incumbent’s market strategies.</p><p> </p><p><strong>Key words:</strong> Strategy, clean tech, barriers, product/market scope</p> / Svenska miljöteknikföretags marknadsexpansion
48

Cleanroom design / "Clean Room" Design.

Erickson, Douglas H January 1987 (has links)
Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Architecture, 1987. / Includes bibliographical references (leaves 147-150). / The development of the integrated circuit which replaced the vacuum tube, started the size reduction process for computer components. These integrated circuits are made from silicon (chips) and are comprised of electronic switches, or gates. The gates are measured in size of microns. The diameter of a human hair is approximately 60 microns across. Facilities that develop, and manufacture these integrated circuits require the strictest guidelines for environmental controls and prevention of potential health hazards that personnel may encounter while working in these facilities. The major environmental controls are particle size and number, temperature, relative humidity, air flow velocity, and pressure. Providing this and other forms of control are used to develop what are called cleanrooms. Cleanrooms are used for the manufacture of a number of different kinds of products. The focus of this research will be on the microelectronics industry. This industry leads all other industries in developing systems, standards, and monitoring technologies, to control microcontamination which is the essence of what a cleanroom does. This thesis will be divided into two parts. The first part defines what a cleanroom is and what it is comprised of. Next, there will be methods presented to design this type of space in a more energy and cost efficient manner. The second part involves the research in the vertical laminar flow aspect of operating a cleanroom. The vertical laminar flow offers a structured method for controlling air flow and provides an effective means for discharging particulates out of the cleanroom. By comparison, the conventional air flow system throws the particulates in a random fashion. The vertical laminar flow has its limitations. By itself, the vertical flow operates well, but people, and equipment cause turbulence which disrupts its effectiveness. Working with these variables through research, an alternate method of working with this vertical laminar flow was developed. The results, recorded by photographs show an alternative for dealing with the turbulence and eddys caused by the operations in the cleanroom. There will be a discussion followed by a number of questions, and responses which will be the basis for this research on vertical laminar flow. / by Douglas H. Erickson. / M.S.
49

An investigation and examination of the levels and types of bacterial contamination on the surface of clean room operators' garments

Smith, Laurie McKenzie January 2018 (has links)
The contamination of sterile pharmaceutical products is a serious event which has in the worst case scenario led to patient death. Operators are the primary source of clean room contamination, with the majority of their detritus being identified as skin squames and their related microorganisms. The ability of operator associated bacterial contamination to disseminate through specialist garments worn in the clean room environment is apparent in the literature. However, despite the fibres of such garments being identified as a suitable substrate for bacteria to adhere to and grow upon, the bacterial bioburden of the surface of clean room operators’ garments is an area which severely lacks in published research. Reported here is the recovery, enumeration and comparison of the levels of bacteria on the surface of reusable antistatic carbon filament polyester clean room garments, using the direct agar contact method, following their laundering with and without terminal gamma sterilisation, immediately following their donning with operators dressing wearing either no gloves, non – sterile gloves or sterile clean room gloves, and following their wear within the clean room environment, with respect to gender. The aforementioned method, with its recovery efficiency shown to be unaffected by agar composition (NA or TSA), recovered bacteria from the surface of garments laundered with and without gamma sterilisation. Such terminal decontamination was shown to reduce the surface bacterial bioburden of the garments, especially at the chest and umbilicus regions, which were shown to harbour higher levels of bacteria than the other sites tested. The direct agar contact method, showing an increase in recovery efficiency following a 48 hour agar incubation period as opposed to a 24 hour period, also recovered bacteria from the surface of clean room garments donned by operators dressing wearing either no gloves, non – sterile gloves and sterile clean room gloves. Bacteria were transferred onto the surface of these garments via the hand borne route, with the chest and oral cavity regions being found to harbour more bacteria than the other sites tested. Overall, glove type was shown to have no effect upon the resultant bacterial bioburden of the surface of the garments, suggesting expensive clean room gloves could be substituted for their cheaper non – sterile equivalents or no gloves during the donning process without subsequently increasing the surface bacterial bioburden of the garment. The direct agar contact method also recovered bacteria from the surface of clean room garments worn by male and female operators, following their working period within a clean room environment. Gender was found to significantly affect the surface bacterial bioburden of the garments, with the surface of those garments worn by male operators being more contaminated than the surface of those worn by their female counterparts. In addition, the donning of a clean room hood was shown to reduce the levels of bacteria at the chest and posterior cervicis regions of suits worn by both genders. Overall, the direct agar contact method was identified as a successful tool to recover, enumerate and estimate the surface bacterial bioburden of reusable antistatic polyester carbon filament clean room garments. Finally, using 16S rRNA gene sequencing, found to be more reliable and accurate at identifying unknown isolates than traditional phenotypic first - stage tests, which were subsequently found to misidentify > 85 % of the isolates tested, a self - selected representative number of isolates recovered from the surface of garments during the laundering and gender comparison studies were predominantly identified as skin commensal species of Staphylococcus and Micrococcus, as well as environmental species of Bacillus. The knowledge contained within this thesis, with respect to clean room operators and their specialist garments, contributes towards improving contamination control standards within clean room facilities.
50

The promise and performance of carbon forestry : analyzing carbon, biodiversity and livelihoods in two projects from India

Aggarwal, Ashish January 2014 (has links)
Carbon forestry projects have proliferated over last few years on the premise of cost efficient climate mitigation along with co-benefits of biodiversity conservation and livelihood improvement. Multilateral, bilateral, public and private sources have invested billions of dollars in the carbon forestry projects based on these claims. However, there is little empirical evidence to support the enthusiasm. This gap is further accentuated by the insufficient understanding of the governance challenges of these projects. These issues are social, political and ecological in nature and hence require a multidisciplinary political ecology framework for a comprehensive analysis. This thesis explores the multiple benefit claims and governance issues by analysing two forestry-based Clean Development Mechanism projects from India. One, in Haryana state focuses on private lands, the other in Himachal involves three different types of lands viz. community, public and private for plantation activities. This thesis examines the carbon, biodiversity and livelihood benefits of each project, and the governance challenges associated with them. I show that both projects have sequestered substantially less carbon than was originally predicted, which has serious implications for carbon revenues and hence economic viability of these projects. In the case of biodiversity, the results are mixed. In Haryana, the tree and herb biodiversity has improved in the project plots as compared to control plots, whereas shrub biodiversity has marginally declined. In case of Himachal project, biodiversity has declined at tree, shrub and herb levels. I have analysed livelihood impacts in terms of foregone crop, fodder and fuel wood benefits across small, medium and large category of farmers. Both the projects have adverse livelihood impacts on the participants, more so in Haryana because of the plantations on private lands. Although the project has adversely affected the livelihoods of all three categories of farmers, however it has affected small farmers the most due to their low incomes and risk-bearing capacities. Hence, these projects have serious equity implications. This thesis also explores the governance challenges of carbon forestry in terms of their interaction with existing policy mechanisms, especially the Forest Rights Act of 2006, which recognises the ownership and use rights of forest dependent communities comprehensively first time in independent India. The analysis suggests that there are various issues that carbon forestry projects pose for the implementation of the Act due to which civil society groups are opposing these projects. This thesis contributes to our understanding of the multiple benefit claims of carbon forestry projects with empirical evidence and a political ecological analysis. It shows that there is possibility of tradeoffs and many other scenarios in carbon forestry projects rather than just the projected 'win-win-win' outcomes. It contributes to the political economy literature by establishing that changes in global commodity markets can influence land use choices at local level, affecting the sustainability of such efforts. This thesis also advances the literature on governance of carbon forestry projects by reflecting on various policy and implementation level issues related to property rights, community institutions, transparency and accountability.

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