The focus of this thesis is in the development and application of a normative framework for handling both variability and uncertainty in making decisions using economic evaluation. The framework builds on the recent work which takes an intuitive Bayesian approach to handling uncertainty as well as adding a similar approach for the handling of variability. The technique of stratified cost effectiveness analysis is introduced as an innovative, intuitive and theoretically sound basis for consideration of variability with respect to cost effectiveness. The technique requires the identification of patient strata where there are differences between strata but individual strata are relatively homogenous. For handling uncertainty, the normative framework requires a twofold approach. First, the cost effectiveness of therapies within each patient stratum must be assessed using probabilistic analysis. Secondly, techniques for estimation of the expected value of perfect information should be applied to determine an efficient research plan for the disease of interest. For the latter, a new technique for estimating EVPI based on quadrature is described which is both accurate and allows simpler calculation of the expected value of sample information. In addition the unit normal loss integral method previously ignored as a method of estimating EVPPI is shown to be appropriate in specific circumstances. The normative framework is applied to decisions relating to the public funding of the treatment of osteoporosis in the province of Ontario. The optimal limited use criteria would be to fund treatment with alendronate for women aged 75 years and over with previous fracture and 77 years and over with no previous fracture. An efficient research plan would fund a randomised controlled trial comparing etidronate to no therapy with a sample size of 640. Certain other research studies are of lesser value. Subsequent to the analysis contained in this thesis, the province of Ontario revised there limited use criteria to be broadly in line with the conclusions of this analysis. Thus, the application of the framework to this area demonstrates both its feasibility and acceptability. The normative framework developed in this thesis provides an optimal solution for decision makers in terms of handling uncertainty and variability in economic evaluation. Further research refining methods for estimating information value and considering other forms of uncertainty within models will enhance the framework.

Diss. (sammanfattning). Uppsala : Sveriges lantbruksuniv. / Härtill 4 uppsatser.

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This study explored energy solutions for Ghana by analysing alternative pathways from 2010 to 2040. The Long-range Energy Alternating Pathways (LEAP) tool was used the scenarios analysis. Four scenarios were developed based on key influencing factors identified in the literature. These are Base case, Coal, Modest Renewable Energy Technology (RET), and High RET scenarios. The Base case scenario was based on government-planned expansion and assumed no shift in policy. The Coal scenario assumed the same expansion trend as Base case with introduction of coal plants replacing a percentage of natural gas generation. Modest and High RET scenarios examined the development of the system with increased renewable energy integration. The results revealed that overall benefits are achieved with higher integration of renewable energy technologies. Economic benefits of 0.5 –13.23% is achieved in the RET scenarios depending on the cost development over the 30 year study period. The high RET offers the highest economic and environmental benefits. Subsequently, the optimal development of the system was examined using the LEAP/OSeMOSYS (Open Source Energy Modelling System) optimisation methodology. The least cost system developed by LEAP (Optimum scenario), was used as a reference to examine future possible energy policy direction in Ghana. The policy constraints analysed included emission targets, carbon taxes and transmission, distribution losses improvements and demand side efficiency. The results show that: suitable policies for clean power generation have an important role in CO2 mitigation in Ghana. The introduction of carbon minimisation policies will also promote diversification of the generation mix with higher penetration of renewable energy technologies. The study proposes promoting energy efficiency and improvement in transmission and distribution losses and utilisation of renewable energy as the best energy strategy for Ghana. Ghana needs ambitious targets, policies and implementation strategies to enhance energy efficiency, and decrease demand in the long term. Stable funding and promotion of transparent policies are required to promote high development of renewable energy technologies.

Made available in DSpace on 2014-10-09T12:55:15Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:04:55Z (GMT). No. of bitstreams: 1 12934.pdf: 10142023 bytes, checksum: 136ed50823f975ac1a6f09494961d4c0 (MD5) / O governo brasileiro com seu programa Luz para Todos tem como desafio acabar com a exclusão elétrica das comunidades rurais do país. Outra preocupação é a respeito da falta de abastecimento de energia, previsto para os próximos anos. No entanto, uma vez atendidas estas demandas há uma tendência de minimizar a exclusão elétrica no país, principalmente em regiões isoladas onde vivem as famílias de baixa renda. Este trabalho tem o objetivo de apresentar um estudo de viabilidade econômica de fontes alternativas de energia para comunidades isoladas do Nordeste brasileiro que não têm acesso à energia elétrica. Inicialmente foi feito um levantamento bibliográfico da utilização das fontes alternativas de energia propostas neste trabalho: eólica, solar e biomassa, que podem ser usadas para suprir a falta de energia elétrica na região do Nordeste do Brasil. Numa segunda etapa foi escolhido o estado Maranhão, pois se tem informações suficientes desta região para aplicar a metodologia proposta no trabalho. A partir desta escolha foi construído um banco de dados com as características típicas da região para as comunidades que possuem entre 1.000 a 10.000 habitantes. Finalmente, foi elaborado um programa de cálculo denominado de PEASEB (Programa de Cálculo de Custos das Energias Alternativas Solar, Eólica e Biomassa), com a finalidade de facilitar os cálculos de viabilidade econômica de cada uma das fontes alternativas de energia propostas neste trabalho. Nestes cálculos foram levados em consideração os impactos ambientais causados por cada uma destas fontes de energia. Com base nos resultados obtidos conclui-se que em termos de custo-benefício as alternativas de energia propostas podem atender as comunidades carentes do Nordeste brasileiro. Além disso, qualquer uma delas pode contar com os recursos naturais que a região possui. No entanto, por meio dos resultados comparativos de viabilidade econômica as energias: eólica e de biomassa apresentaram os melhores resultados. As conclusões deste trabalho podem contribuir com os projetos de geração de energia e inclusão social do governo federal, possibilitando assim, o crescimento econômico do país / Dissertação (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

Global pressure to reduce greenhouse gas (GHG) emissions, energy security concerns and increasing demand for liquid fuels incentivize the search for more sustainable and secure alternative methods for producing liquid fuels with improved efficiency and reduced environmental impacts. One of the economically attractive examples of these alternate methods is the gas-to-liquid process, however, its environmental impacts are worse than traditional petroleum refining. Carbon capture and sequestration is an option to reduce greenhouse gas emissions of processes, but it decreases the efficiency of the process and often results in economic infeasibility. Instead, integrating different processes and feedstocks was demonstrated to improve the efficiency, economic and environmental performance of the processes. The focus of this thesis is to design and simulate a novel integrated biomass, gas, nuclear to liquids (BGNTL) process with negative greenhouse gas emissions. In this process, nuclear heat from a high temperature gas-cooled reactor (HTGR) is used as the heat source for a steam methane reforming (SMR) process. The integrated HTGR and SMR process requires detailed analysis and modeling to address key challenges on safety, operability, economic and environmental impacts of the integrated process. To this end, a rigorous first principle based mathematical model was developed in gPROMS modeling environment for the integrated HTGR/SMR process. The results for a large scale design of this system indicate that hydrogen rich syngas with H2/CO ratio in the range of 6.3 can be achieved. To meet the desired H2/CO ratio (around 2) required for the downstream fuel synthesis processes, the HTGR/SMR derived syngas can be blended with a hydrogen lean syngas from biomass gasification. In this thesis, the large scale design of the BGNTL process to synthesize gasoline, diesel and dimethyl ether (DME) is investigated. The results from the gPROMS model of the integrated HTGR/SMR system are used for simulating the BGNTL process in Aspen Plus. The performance of the BGNTL process was compared with a biomass, gas to liquids (BGTL) process. The efficiency, economics, and environmental impact analyses show that the BGNTL process to produce DME is the most efficient, economic and environmentally friendly process among all the considered designs. The results demonstrate that process integration exploits certain synergies that leads to significantly higher carbon and energy efficiencies and lower greenhouse gas emissions. In addition, it was found that all the studied designs yield a net negative greenhouse gas emissions when carbon capture and storage technology is implemented. As another sustainable alternative to meet the required H2/CO ratio of the syngas when biomass resources are not available, it is proposed to apply the nuclear heat to the mixed reforming of methane. This represents using steam and waste CO2 to reform methane into valuable syngas. The developed model for the integrated HTGR/SMR system is extended to the mixed reforming of methane (MRM) process and it was demonstrated that integrated HTGR/MRM process can be a promising option to achieve certain desired H2/CO ratios for the downstream energy conversion processes. / Thesis / Doctor of Philosophy (PhD)

Yes / Introduction As a consequence of the low cost and perceived safety, proton pump inhibitors (PPIs) are widely prescribed but they can cause longterm adverse effects and are often overprescribed. For most patients PPIs should not be continued long-term as patients can become dependent on PPIs and they are rarely stepped down/off treatment. We aimed to measure whether a dyspepsia review service could help patients on PPIs to step down/off treatment whilst still keeping them symptom free. Methods Pharmacists were provided with training on dyspepsia management. Four general practices were selected. Patients taking a PPI for more than two months were included. A list of exclusion criteria (e.g. active ulcers, newly initiated) was applied. Between six and eight dyspepsia review clinics were run at each site. Patients were booked into a 15-minute consultation. A concordance style consultation was held with clinicians providing information on dyspepsia management and exploring the patients’ ideas, concerns and expectations about stepping down or stepping off treatment. A follow-up audit was performed at four months to determine if patients had remained stepped down/off. An economic evaluation of clinic costs and drugs savings was performed. Results A total of 508 patients were invited to a review; 136 did not attend and 58 were excluded due to not meeting the inclusion criteria, leaving 314 patients reviewed for step-down/step-off. Successful step down/step off was achieved in 257 people (82% of those reviewed). The total cost savings of PPIs was £7,100. The additional cost of alginates was £1,207 giving a net saving on medicines of £5,893 per annum. Set-up costs were £1,194 and staff costs £3,524 to £5,156 giving total running costs, which vary dependent on the Agenda for Change (AfC) grade of pharmacist involved, of £4,720 - £6,351. Conclusion A dyspepsia review clinic is cost-neutral to run but, given that many patients are on polypharmacy, PPI step down might best be considered as part of a holistic medication review clinic. / Reckitt Benckiser, National Institute for Health Research, Health Education England

Urban areas contain significant amounts of asphalt pavement. When exposed to the sun, asphalt pavement absorbs solar radiation and stores it as thermal energy raising its temperature. According to the urban heat island effect (UHIE), the pavement releases the thermal energy back to the surrounding air resulting in a rise in local air temperature. A pipe network containing a passing fluid installed in the pavement can reduce the UHIE. The fluid captures the thermal energy stored in the pavement, reducing air and pavement temperatures as well as providing heated water for other applications. The heat transfer/harvesting system can be optimized to produce the desired cooling of the pavements. This research addresses the economic feasibility of a pipe network by design as well as structural performance through computer modeling. To design the pipe network and predict its economic feasibility an Excel spreadsheet was programmed. It requires local air temperature data to determine the yearly temperature profile within the pavement and to calculate the amount of thermal energy that could be extracted. By varying design parameters such as fluid flow rate, it produces a matrix of payback periods. Structural conditions were considered for the installation of the proposed system. To simultaneously evaluate the thermal and structural performance of the pipe network installation, a finite element model was created using COMSOL Multiphysics©. A typical value of solar radiation and a standard truck tire wheel load were applied to the model to simulate the intended application of the pipe network. The result of this thesis is a method and a tool to design and analyze with respect to economic and structural performance a pipe network used to extract the thermal energy stored in asphalt pavements and reduce the UHIE.

Biomass conversion into forms of energy is receiving current attention because of environmental, energy and agricultural concerns. The purpose of this thesis is to analyze the environmental, energy, economic, and technological aspects of using a form of biomass, switchgrass (panicum virgatum), as a partial or complete replacement for coal in power generation and cogeneration systems. To examine the effects of such a substitution, an environmental biocomplexity approach is used, wherein the agricultural, technological, economic, and environmental factors are addressed. In particular, lifecycle analysis (LCA) and a three-dimensional integrated economic, energy and environmental analysis is employed. The effectiveness of alternate technologies for switchgrass preparation, harvest and use in terms of greenhouse gas impact, cost and environmental implications is examined. Also, different scenarios of cofiring and biomass preparation pathways are investigated. Optimization of the total biomass power generation cost with minimum greenhouse gas effect is undertaken using mathematical programming for various alternate competitive biomass processing pathways. As a byproduct of this work a generic tool to optimize the cost and greenhouse gas emissions for allocation of fuel sources to the power generating sinks is developed. Further, this work discusses the sensitivity of the findings to varied cofiring ratios, coal prices, hauling distances, per acre yields, etc. Besides electricity generation in power plants, another viable alternative for reducing greenhouse gases (GHGs) is the utilization of biomass in conjunction with combined heat and power (CHP) in the process industries. This work addresses the utilization of biowaste or biomass source in a processing facility for CHP. A systematic algebraic procedure for targeting cogeneration potential ahead of detailed power generation network design is presented. The approach presented here effectively utilizes the biomass and biowaste sources as external fuel, and matches it with the use and dispatch of fuel sources within the process, heating and non-heating steam demands, and power generation. The concept of extractable energy coupled with flow balance via cascade diagram has been used as a basis to construct this approach. The work also discusses important economic factors and environmental policies required for the cost-effective utilization of biomass for electricity generation and CHP.

The focus of this study is the economic feasibility of drip irrigation adoption using capital budgeting and quadratic programming techniques. The capital budgeting techniques used in the study are net present value (NPV) and returns above specified costs (RASC). Modified crop enterprise budgets incorporating drip irrigation are developed based on data from Texas AgriLife Extension Service crop enterprise budgets and published literature focusing on costs and returns of drip irrigation. The quadratic programming technique considers risk and incorporates the modified crop enterprise budgets to estimate a cropping pattern that maximizes the net income above specified costs for the region. The RASC per acre for drip-irrigated crops ranged from $56.34 to $1,909.03, while the RASC per acre for flood-irrigated crops ranged from $142.51 to $1,488.12. Flood-irrigated onions, cotton, and sugarcane had higher RASCs per acre, while the RASCs were greater for drip-irrigated grapefruit and oranges. Evaluating the NPV of the crops resulted in similar results; only grapefruit and oranges were economically-feasible drip-irrigated crops. The baseline results identified levels of drip irrigation adoption ranging from 52,000 acres to 64,497 acres as levels of risk were varied. The level of water available at the reservoir suggested minimal impacts on the level of drip-irrigation adoption, but serious implications for the agriculture economy. Several sensitivity scenarios concentrated on the implications of yield response and water savings that result from the adoption of drip irrigation. The greatest amounts of drip-irrigated crops were present when the yield responses were 130% of the flood-irrigated crops with a 20% water savings. As the amount of water available was reduced, the amount of drip-irrigated crops ranged from 46,111 acres to 59,724 acres. Drip irrigation appears to be an economically-viable alternative in the LRGV due to the presence of drip-irrigated crops in the entire myriad of scenarios investigated in this research. If producers are only concerned with the bottom line as provided by the RASC analysis and no other variables such as water availability, risk, and crop rotations affecting the decision making process, only drip-irrigated grapefruit and oranges are economically competitive with conventional irrigation systems.