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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.
201

Solar cells on hydro power plants : A feasibility study

Lenner, Johan January 2015 (has links)
Parts of the auxiliary power systems at Fortum's hydro power stations are usingdirect current, which is fed from the generators at the plant and converted byrectifiers. As photovoltaic solar cells produce direct current there are severalhypothetical advantages to use solar power for the auxiliary power supply, e.g.enabling more of the power from the generator to be sold to the grid. It eliminatesthe need of an inverter, conversion losses are avoided and less load is put on therectifiers. However the exclusion of an inverter also prevents the solar cells to have adirect connection to the grid, which in turn makes them ineligible for the Swedishgovernmental solar power investment support program. The lesser load on therectifiers will not affect their lifetime according to manufacturers and thus achieves noeconomic gain. Avoiding conversion losses will increase the gain from the producedelectricity by enabling even more power to be sold to the grid. The economic gainfrom avoiding conversion losses is however too small to gain any feasibility in a smallsolar power installation at a hydro power plant, as the small size will make itexpensive in terms of investment per Wp.
202

An Evaluation of the Prevent-Teach-Reinforce (PTR) Model in a Community Preschool Setting

Kulikowski, Laura L. 18 October 2010 (has links)
This study evaluated the use of the Prevent-Teach-Reinforce (PTR) model with two four-year-old children in a community preschool classroom. A multiple baseline design across activities was used to assess the teacher implementation of the behavior intervention strategies developed during the PTR team process and the changes in child problem behavior and engagement. Additional measures associated with the outcomes, such as researcher procedural integrity and social validity were assessed. The results suggest that the team of teachers were able to implement the PTR intervention with fidelity, which resulted in a decrease in the children’s problem behavior and an increase in their engagement. The PTR process was deemed feasible and acceptable by the teaching staff, and that the child behavioral outcomes were evaluated as acceptable by naïve observers.
203

Innovate On A Shoestring : Product development for the Least Developed Countries and what we can re-use in the Established Markets

Ottosson, Hans January 2015 (has links)
By understanding current approaches and methods of product development (PD) combined with knowledge of the needs and know-how of customers in the least developed countries (LDCs) associated risks and excessive costs can be avoided. The main purpose of this thesis is to highlight the important need of developing products and services for the LDCs and to look at current practices for PD and to distill these into one method for developing products pertinent to LDC needs and markets. Conversely, the second purpose for this thesis is to examine possible LDC based development tools that can be applicable when designing for the more established markets. There are also crucial social, cultural, economic and political reasons for addressing LDC related issues. The goal is to show companies of all sizes that it can be profitable to expand to new markets in the LDCs and also that the steps used there can help generate new revenue when implemented in their current markets, as well as to provide them a model for it. This thesis includes and clearly demonstrates the importance of development involvement on the local level and the benefit of using complementors. The thesis data and conclusions are based on literature studies and an extended stay in the Dominican Republic. It is here observed that by getting closer to the end customer, a company will get an increased understanding and knowledge that provides an advantage over the competition. And for companies to succeed in the LDCs, the three most significant things to consider are: 1) to find the specific needs of the customer, 2) design for affordability, and 3) to source and manufacture locally. It will be seen that the benefits to such an approach extend outward in essentially all directions.
204

"Lorna" įstaigos galimybių studija / Lorna Office's Feasibility Study

Poškaitė, Vaida 07 June 2006 (has links)
SUMMARY Lorna Office’s Feasibility Study, conducted by Ms. Vaida Poškaitė Final Work for Master’s Degree Šiauliai 2006 A feasibility study regarding the office’s activities and its development prospects was performed in the medical office Private Limited Liability Company LORNA during the period of 2004 and 2006 and these major propositions should be claimed from its outcomes: Private Limited Liability Company LORNA was registered in 1997 and it has been rendering medical services since then. The most significant advantage of the medical centre LORNA is the high quality of the rendered services. 55 people, 34 doctors out of them, are employed at this Centre. The largest portion of LORNA’s revenues is received from medical and dentist services. Private Limited Liability Company LORNA is also financed by the State Patient Fund, therefore, there is an opportunity to set up a family doctor’s position as well as an office for public medical education. The accounting analysis of medical centre LORNA shows that the company has been running profitably, because the net profit has been increasing. The revenues from health supervision services in 2005 have increased about 10% in comparison with 2003. Doctors of Private Limited Liability Company LORNA are rendering their services not only to people from Klaipėda, but also from Klaipėda district, Šilutė, Plungė, Kretinga and Skuodas as well as their districts. One third of all patients are people, residing in various districts... [to full text]
205

DEVELOPMENT OF NATURAL GAS OCEAN TRANSPORTATION CHAIN BY MEANS OF NATURAL GAS HYDRATE (NGH)

Nogami, Tomonori, Oya, Nobutaka, Ishida, Hiroshige, Matsumoto, Hitoshi 07 1900 (has links)
While alternative natural gas transportation technologies against currently available pipeline or liquefied natural gas (LNG) are expected to develop to be suitable for small and medium or remote gas fields, Mitsui Engineering & Shipbuilding Co., Ltd. (MES) has been studying natural gas hydrate (NGH) transportation chain and advocated at ICGH2005 the NGH chain was economical compared with conventional LNG system under some conditions. Meanwhile, MES has been carrying out research and development on the relevant technology development including construction of 600 kg/day class NGH production and pelletizing plants and a re-gasification facility and the process technology resulted from this R&D leads to the forthcoming demonstration plant of 5 ton/day production (under construction) to be dedicated to the demonstration project of small-lot NGH land transportation in western Japan. As the latest achievement, MES and Mitsui & Co., Ltd. (Mitsui) established NGH Japan Co., Ltd. (NGHJ) in April 2007, in order to study in detail on actual viability of NGH ocean transportation chain. NGHJ, MES and Mitsui have been conducting a practical feasibility study on certain cases in Southeast Asia in cooperation with 6 Japanese leading companies related to natural gas businesses. The study suggests that NGH chain was appropriate as a media for transportation from Southeast Asia to Japan and regional transportation within Southeast Asia in view of economics.
206

A Study on the Technical and Economic Feasibility for Arable Agriculture and Biofuel Production on Landfill Covers in Southern Ontario

Battiston, Lee Anthony 14 February 2013 (has links)
There are over 3,700 active and decommissioned municipal solid waste (MSW) landfill sites located in Ontario (MOE, 1991). Under current legislation, these landfill sites must be rehabilitated to a defined end use when decommissioned. In Ontario, the primary prescribed end use of closed landfills is typically agriculture, and that end use can lead to food-consumer concerns, due to the perceived risk of potential contamination from legacy materials found in landfills. Converting these sites to produce biomass-energy crops instead of food crops could mitigate that concern and also help to avoid the current controversy with bioenergy-crop production on high-capability agricultural land. In this study, a 3.5-year field program with subsequent verification and analysis investigated and developed rehabilitation prescriptions using locally obtained topsoil and soil-forming materials (subsoil) to develop anthropogenic soil profiles on top of a sealed landfill cover (clay cap). These prescriptions provided crop productivity at least as good as, and generally better than, local agricultural soils. Mixed forages and biomass-specific crops (warm season grasses) were grown on these soils in replicated plot trials to evaluate the efficacy of a range of soil treatments. Following establishment of technical feasibility for site rehabilitation, economic modeling was conducted to determine the feasibility of using these anthropogenic soils for the production of forage crops, biofuel feedstock, and simple energy products at a scale consistent with typical landfill sites in Ontario. An economic model was developed to aid proponents in selecting appropriate rehabilitation methods and to assess potential bioenergy-crop outputs for their site. This study demonstrated that while it is technically feasible to rehabilitate these waste sites to produce agricultural crops and/or biofuel feedstock, the scale of typical landfill sites makes it very difficult to compete, from an economic perspective, with conventional energy sources. However, the diverted incoming materials, such as leaf and yard waste, compostable biosolids, and paper mill waste, can be used in the development of manufactured soil profiles for rehabilitation, significantly reducing rehabilitation costs and facilitating more cost-competitive production of agricultural and biomass feedstock crops. / Niagara Waste Systems Limited, a division of Walker Industries Holdings Limited, MITACS
207

Validation of quality indicators for radical prostatectomy

Chan, Ellen Oi Man 29 August 2007 (has links)
BACKGROUND: Radical prostatectomy is the surgical procedure performed on men with clinically localized prostate cancer. In recent years, radical prostatectomy quality indicators have been recommended, but the feasibility and validity for many of these listed surgical quality indicators have yet to be examined. We tested the convergent construct validity of these quality indicators by assessing their associations with hospital volume, a variable repeatedly associated with the quality of surgical care, for prostate cancer patients treated with radical prostatectomy. OBJECTIVES: (1) To assess variations in quality indicators by hospital volume; and (2) To investigate whether certain explanatory variables account for some of the variation observed in Objective 1. METHODS: This was a retrospective cohort study using medical chart review data that had already been collected as part of a parent study. The study population consisted of a stratified random sample of prostate cancer patients diagnosed between 1990 and 1998 in Ontario, who were treated by radical prostatectomy with curative intent within six months of diagnosis (n = 645). The feasibility of using this data to assess a number of quality indicators was explored, and where possible, variables were developed for analysis. Ultimately, detailed analyses were performed for the quality indicators: total blood transfusions of three units or greater, length of hospital stay, and use of non-nerve-sparing surgical technique. RESULTS: Even using high-quality chart data, it was not feasible to evaluate all of the quality indicators that were explored. For blood transfusions of three units or greater, length of hospital stay, and use of non-nerve-sparing surgical technique, worse outcomes were generally apparent with decreasing hospital volume, both before and after adjusting for the effect of explanatory variables. CONCLUSIONS: We demonstrated convergent construct validity for three quality indicators (blood transfusions, length of hospital stay, and non-nerve-sparing surgery). If their validity is further demonstrated in future studies, these indicators could be used for quality assessment and could provide feedback to surgeons, surgical department heads, hospital administrators, and quality councils by suggesting areas for quality improvement in surgical care, such that future outcomes can be optimized. / Thesis (Master, Community Health & Epidemiology) -- Queen's University, 2007-08-23 17:53:33.166
208

Active neutralisation and amelioration of acid mine drainage with fly ash

Damini Surender January 2009 (has links)
<p>Fly ash and AMD samples were characterised by standard analytical methods for selection of the test materials. Active treatment by means of mixing fly ash with AMD in beakers and a large tank at pre-determined ratios have shown that fly ash is capable of neutralising AMD and increasing the pH beyond neutral values, which optimises the removal of heavy metals and ions. The trend was: the more fly ash added the quicker was the reaction time and higher the pH values achieved. Iron was reduced by as much 99 % in beaker scale experiments via Fe(OH)3 precipitation at pH values &gt / 4.0. A 99 % decrease in aluminium concentration was observed which was attributed to the precipitation of primarily gibbsite and various other mineral phases at pH values &gt / 5.5. As the pH increases, sulphate is adsorbed via Fe(OH)3 and gypsum precipitation at elevated pH. Sulphate attenuation with fly ash was excellent, achieving 98 % attenuation with beaker scale experiments and 1:1 fly ash:AMD ratio. Sulphate attenuation with fly ash was comparable to membrane and ion exchange systems and exceeded the performance of limestone treatment. Except for the larger volumes of fly ash needed to neutralise the AMD, fly ash proved to be a feasible and cost efficient alternative to limestone treatment. Fly ash produced competing results to limestone concerning acidity removal and sulphate attenuation. The comparison highlighted the advantages of utilising fly ash in comparison to limestone and demonstrated its cost effectiveness. The results of this study have shown that fly ash could be successfully applied for the neutralisation of acid mine drainage (AMD) and effectively attenuate the sulphate load in the treated water. The critical parameters to this technology are the variations of chemical composition and mineralogy of fly ash, which could influence the pH, contact time of the neutralisation reaction, and the same is true if the AMD quality varies.</p>
209

Dynamic fixture planning in virtual environments

Kang, Xiu Mei 23 September 2010 (has links)
Computer-aided fixture planning (CAFP) is an essential part of Computer-aided design and manufacturing (CAD/CAM) integration. Proper fixture planning can dramatically reduce the manufacturing cost, the lead-time, and labor skill requirements in product manufacturing. However, fixture planning is a highly experience-based activity. Due to the extreme diversity and complexity of manufacturing workpieces and processes, there are not many fixture planning tools available for industry applications. Moreover, existing CAFP methods rarely consider integrating fixture environmental factors into fixture planning. Automatic fixture planning using VR can provide a viable way for industries. This thesis develops automated approaches to fixture planning in a virtual environment (VE). It intends to address two important issues: automatic algorithms for fixture planning, and the VE to support high fidelity evaluation of fixture planning. The system consists of three parts including fixture assembly planning, feasibility analysis of assembly tools, and motion planning for fixture loading and unloading. The virtual fixture planning system provides the fixture designer a tool for fixture planning and evaluation. Geometrical algorithms are developed to facilitate the automatic reasoning. A Web-based VE for fixture planning is implemented. The three-dimensional (3D) model visualization enables the fixture simulation and validation effectively to investigate existing problems. Approaches to construct desktop-based large VEs are also investigated. Cell segmentation methods and dynamic loading strategies are investigated to improve the rendering performance. Case studies of virtual building navigation and product assembly simulations are conducted. The developed algorithms can successfully generate the assembly plan, validate the assembly tools, and generate moving paths for fixture design and applications. The VE is intuitive and sufficient to support fixture planning, as well as other virtual design and manufacturing tasks.
210

The feasibility of implementing a point-of-use micronutrient fortification among African pre-school children : a pilot study / Ogunlade, Adebayo Olakunle

Ogunlade, Adebayo Olakunle January 2009 (has links)
Background The high prevalence of micronutrient deficiencies among South African preschool children reinforces the need for an intensified micronutrient malnutrition control strategy targeting children at home or in school. The use of recently developed micronutrient powders also known as "in-home fortification" or "point-of-use fortification" can be an effective long-term, sustainable approach in improving early childhood nutrition and cognitive developmental potential. However, before embarking on large-scale, long-term, point-of-use fortification trials, it is imperative to conduct external pilot trials in which the feasibility of implementing full-scale studies can be effectively assessed. Objective The objective of this study was to assess the feasibility of implementing a point-of-use micronutrient fortification trial among African preschool children, which would aid in pilot-testing the study design, logistics and implementation process as well as reveal limitations which can be addressed before the implementation of full-scale trials. Methods Preschool children (n = 151), aged 36 -79 months with haemoglobin concentration (Hb)<= 12.5 g/dL, from eight schools in a low socio-economic community were randomly assigned to an intervention (n = 76) and a control (n = 75) groups, both receiving breakfast maize-meal porridge, either with added micronutrient or placebo powder for 52 school days. Several process evaluation indicators (fidelity, dose delivered, dose received, reach, recruitment and context) were used to assess trial feasibility. Selected indicators of early childhood development (Hb concentration, anthropometric indices and cognitive function) were used to evaluate the outcome of the intervention within the context of a pilot study. Results The process evaluation results indicate that the various implementation components were delivered with high fidelity. Capacity development and strengthening of the front-line staff cognitive assessors and study assistants) was executed as planned. The point-of-use fortificant was well accepted among the children and the mean percentage of days the point-of-use fortificant or placebo was consumed (~85%) did not differ between the groups. There were significant increases in Hb concentration (p < 0.05) from baseline to follow-up in both the intervention [mean change: 0.38 g/dL (95% CI: 0.14, 0.61 g/dL)] and control [mean change: 0.57 g/dL (95% CI: 0.35, 0.80 g/dL)] groups, however, mean change did not differ significantly between the groups (p = 0.250). The intervention did not improve any of the anthropometric indices measured in the intervention group compared to control. However, there was a medium likelihood for practical significance for the two global cognitive scores assessed, nonverbal index [intervention effects: 7.20 (95% C!: 2.60,11.81); P = 0.002, effect size: 0.55] and mental processing index [intervention effects: 2.73 (95% CI: 0.25,5.70); P = 0.072, effect size: 0.36] on the Kaufman Assessment Battery for Children, second edition. Conclusion The feasibility of implementing a point-of-use micronutrient fortification trial was demonstrated among African preschool children with potential benefits of improving their cognitive function. The most important lessons learned from this trial that could help improve similar future large-scale trials included the recruitment and training of the most eligible front-line staff as well as identifying that the use of a simple field-friendly finger prick method to measure Hb concentration may not be sufficiently sensitive to show differences in iron status after the intervention. / Thesis (M.Sc. (Nutrition))--North-West University, Potchefstroom Campus, 2010.

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