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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.
1

Kostnaden för CCS vid Cementa AB i Degerhamn

Nyberg, Jesper January 2016 (has links)
CCS, Carbon Capture and Storage, innebär infångning och lagring av koldioxid från stora punktutsläpp. Detta gör cementindustrin aktuell för implementering av CCS. Stora delar av branschens koldioxidutsläpp går inte att eliminera på annat sätt. Kostnaden för monoetanolamin-baserad post-combustion capture med efterföljande transport och lagring av koldioxiden vid cementfabriken Cementa AB i Degerhamn undersöktes. Studiens kostnadsberäkningar är baserade på publicerade uppgifter om kostnaden för koldioxidinfångning vid den norska cementfabriken Norcem Brevik, och på publicerade uppgifter om kostnaden för transport av koldioxid till en lagringsplats i Östersjön. Cementa Degerhamns koldioxidutsläpp kan reduceras med 5,4 miljoner ton under en 25-årsperiod till en kostnad av 2,2 miljarder SEK. Slutresultatet, som uttrycks i måttet Cost of CO2 avoided, ger en kostnad på 890 SEK/ton CO2. En känslighetsanalys visar att av de undersökta parametrarna är storleken på koldioxidutsläppen och kostnaden för användning och underhåll viktigast för storleken på Cost of CO2 avoided. Vidare studier behövs för en mer exakt beräkning av kostnaden för CCS vid Cementa Degerhamn. / CCS, Carbon Capture and Storage, involves the capture and storage of carbon dioxide from large point sources. This makes the cement industry suitable for the implementation of CCS. Large parts of the industry's carbon dioxide emissions cannot be eliminated by other means. The cost of monoethanolamine-based post-combustion capture and subsequent transport and storage of the carbon dioxide at the cement factory Cementa AB in Degerhamn was studied. This study's cost estimates are based on published data on the cost of carbon capture at the Norwegian cement plant Norcem Brevik, and on published data on the cost of transport of carbon dioxide to a storage site in the Baltic Sea. Cementa Degerhamn’s carbon dioxide emissions can be reduced by 5.4 million tons over a 25 year period to a cost of 2.2 billion SEK. The result, expressed in Cost of CO2 avoided, gives a cost of 890 SEK/ton CO2. A sensitivity analysis shows that of the examined parameters, the size of the carbon dioxide emissions and the cost of use and maintenance are the most important for the size of Cost of CO2 avoided. Further studies are required for a more accurate calculation of the cost of CCS at Cementa Degerhamn.
2

Retention of the Incompletely Learned Avoidance Response: The Effects of Handling and Location During the Intersession Interval / Retention of the Incompletely learned Avoidance Response

Anderson, Nancy 08 1900 (has links)
The retention curve of an incompletely learned avoidance response was investigated, employing rats in a shuttlebox situation. Subjects were given a 15 trial re-learning session 0, 1/2, 1 or 24 hours after original acquisition. Three treatment groups were tested at these intervals: a not-handled group which remained in the shuttlebox during the intersession interval, a handled group which remained in the shuttlebox during the intersession interval, and a group which was returned to a living cage. All treatment groups produced a monotonically decreasing curve as a function of intersession interval. Handling produced a decrement on performance at 0-hour intersession interval; location showed no effect. Results were interpreted in terms of the warm-up decrement and the effects of handling on the arousal of fear. / Thesis / Master of Arts (MA)
3

[en] ENERGY EFFICIENCY POLICIES IN BRAZIL: AN ECONOMIC ENVIRONMENT UNDER UNCERTAINTY APPROACH / [pt] POLÍTICAS DE EFICIÊNCIA ENERGÉTICA NO BRASIL: UMA ABORDAGEM EM UM AMBIENTE ECONÔMICO SOB INCERTEZA

RODRIGO FLORA CALILI 08 January 2015 (has links)
[pt] A eficiência energética (EE) terá um papel cada vez mais importante para garantir o futuro das novas gerações. Assim, o objetivo principal deste trabalho é estimar o quanto o PNEf (Plano Nacional de Eficiência Energética), publicado pelo governo brasileiro no final de 2011 irá economizar ao longo dos próximos 5 anos, evitando a construção de usinas de energia adicionais, bem como reduzindo a emissão de gases de efeito estufa na atmosfera. É também objetivo deste trabalho definir as premissas e formular diretrizes para que um possível leilão de eficiência energética seja implantado no Brasil. O custo marginal de operacão é calculado no planejamento de médio prazo do despacho para o sistema hidro-térmico brasileiro utilizando Programação Dinâmica Dual Estocástica. Foi incorporado no modelo do despacho hidro-térmico as políticas de eficiência energética de forma estocástica, havendo assim, vários cenários para a demanda de energia elétrica. Demonstrou-se que, mesmo para uma modesta redução do consumo com políticas de eficiência energética (menor que 1 porcento por ano), há uma economia nos próximos 5 anos em torno de 237 milhões de reais no cenário conservador e 268 milhões de reais no cenário otimista. Em comparação, a nova usina hidrelétrica Belo Monte irá custar em torno de 26 bilhões de reais a serem pagos ao longo de um período de 30 anos (ou seja, 867 milhões de reais em 1 anos). Conclui-se que, políticas de eficiência energética são preferíveis à construção de uma nova usina, mesmo sendo esta de fonte hidráulica. / [en] Energy efficiency will play an increasingly important role in future generations. The aim of this work is to estimate how much the PNEf (National Plan for Energy Efficiency) launched by the Brazilian government in 2011 will save over the next 5 years by avoiding the construction of additional power plants, as well as the amount of the CO2 emission. Besides, it is the aim of this work introduces the premises and guidelines of a possible demand side bidding in Brazil. The marginal operating cost is computed for medium term planning of the dispatching of power plants in the hydro-thermal system using Stochastic Dynamic Dual Programming, after incorporating stochastic energy efficiencies into the demand for electricity. We demonstrate that even for a modest improvement in energy efficiency (less than 1 percent per year), the savings over the next 5 years range from 237 million reais in the conservative scenario to 268 million reais in the optimistic scenario. By comparison the new Belo Monte hydro-electric plant will cost 26 billion reais to be repaid over a 30 year period (i.e. 867 million reais in 1 years). So in Brazil energy efficiency policies are preferable to building a new power plant.
4

Modeling Reductions in Greenhouse Gases in Arizona Resulting from California Demand Side Management Programs

January 2013 (has links)
abstract: The State of California has made great strides in reducing greenhouse gas (GHG) emissions through mandated, rate-payer funded Investor Owned Utility (IOU) electricity Demand Side Management (DSM) programs. This study quantifies the amount of reduced GHG emissions in Arizona that result from DSM in that state, as well as the DSM reductions within Southern California Edison (SCE), Pacific Gas and Electric (PG&E;), and San Diego Gas and Electric (SDG&E;) during the 2010 through 2012 California Public Utilities Commission (CPUC) DSM program cycle. To accomplish this quantification, it develops a model to allocated GHG emissions based on "operating margin" resources requirements specific to each utility in order to effectively track, monitor, and quantify avoided emissions from grid-based utility resources. The developed model estimates that during the 2010-2012 program cycle, 5,327.12 metric tons (MT) of carbon dioxide equivalents (CO2e) in GHG reductions (or 1.8 percent of total reductions) can be attributed to reduced demand from Arizona--based resources by California IOUs. By focusing on the spatial context of GHG emission reductions, this study models and quantifies the spill-over effect of California's regulatory environment into neighboring states. / Dissertation/Thesis / Ph.D. Geography 2013
5

Avoiding greenhouse gas emissions using flexibility in smart thermal grids

Hennessy, Jay January 2023 (has links)
The Paris Agreement on climate change entered into force in 2016 and has been ratified by 193 of the 197 Parties to-date, followed by country targets to cut greenhouse gas emissions, not least through an increasing penetration of renewable energy sources. In its 2021 annual World Energy Outlook, the IEA envisages a Net-Zero Emissions by 2050 scenario (NZE) in which renewables as a percentage of total energy supply increase from around 10% in 2020 to over 65% in 2050 and is reflected by a similar change in the percentage of variable renewables in total generation, thereby increasing the need for system flexibility. Thermal grids are a significant supplier of heat to buildings in Europe, Russia and China, providing 45 % of heat in some European countries. One of the advantages of district heating is its ability to consume multiple fuel sources, including electricity. Technologies for converting heat back to electricity mean that, in theory, district heating can adjust both the consumption of electricity, and potentially supply electricity, to provide short-term flexibility and ancillary services to the power grid, and thus may help to meet future system flexibility needs. This thesis describes the results of literature reviews and a techno-economic study to determine and quantify the potential for thermal grids to address future system flexibility needs, through possible contributions to the electricity balancing market or provision of ancillary services. These studies focus on the potential use of heat-to-power technologies in thermal grids; on identifying and quantifying short term heat storage options that can be used for increased flexibility in thermal grids; and whether the use of this flexibility could contribute to reduced curtailment of renewable electricity sources, leading to avoided emissions.  The results show that most thermal grids have multiple options for the storage of heat, with storage capacity already available that could potentially be used to provide additional flexibility. Stored heat may be converted to electricity with commercially available heat-to-power technologies, although economic feasibility may still be limited. It is shown that if storage flexibility is used to reduce the curtailment of renewable energy sources at a country scale through power-to-heat technology, this storage flexibility can lead to megatonnes of avoided CO₂eq emissions.
6

Conical Intersections and Avoided Crossings of Electronic Energy Levels

Gamble, Stephanie Nicole 14 January 2021 (has links)
We study the unique phenomena which occur in certain systems characterized by the crossing or avoided crossing of two electronic eigenvalues. First, an example problem will be investigated for a given Hamiltonian resulting in a codimension 1 crossing by implementing results by Hagedorn from 1994. Then we perturb the Hamiltonian to study the system for the corresponding avoided crossing by implementing results by Hagedorn and Joye from 1998. The results from these demonstrate the behavior which occurs at a codimension 1 crossing and avoided crossing and illustrates the differences. These solutions may also be used in further studies with Herman-Kluk propagation and more. Secondly, we study codimension 2 crossings by considering a more general type of wave packet. We focus on the case of Schrödinger equation but our methods are general enough to be adapted to other systems with the geometric conditions therein. The motivation comes from the construction of surface hopping algorithms giving an approximation of the solution of a system of Schrödinger equations coupled by a potential admitting a conical intersection, in the spirit of Herman-Kluk approximation (in close relation with frozen/thawed approximations). Our main Theorem gives explicit transition formulas for the profiles when passing through a conical crossing point, including precise computation of the transformation of the phase and its proof is based on a normal form approach. / Doctor of Philosophy / We study energies of molecular systems in which special circumstances occur. In particular, when these energies intersect, or come close to intersecting. These phenomena give rise to unique physics which allows special reactions to occur and are thus of interest to study. We study one example of a more specific type of energy level crossing and avoided crossing, and then consider another type of crossing in a more general setting. We find solutions for these systems to draw our results from.
7

Quantification of a Swedish Digitalization Company´s GHG Emission : A Single Case Study

Rydén, Joakim, Sandegård, Fabian January 2020 (has links)
Research shows that the warming of the climate over the last century is extremely likely due to human activities. Furthermore, there is a need for an understanding how business activities counteract or contribute to climate change. In particular, the digitalization industry is often introduced as an important player in climate challenge. However, research also concludes that the digitalization industry’s impact on the climate is ambiguous, since it in some cases contributes to climate change and in other cases counteracts it. In order to understand the interplay between greenhouse gas emissions and digital solutions, it is necessary to outline and quantify the emissions from particular digitalization projects and furthermore the industry itself. The thesis takes off in a single case study at a Swedish digitalization consultancy company in order to investigate how both internal greenhouse gas emissions and greenhouse gas emissions from customer projects can be quantified as accurate and as often as possible. The findings disclose that greenhouse gas (GHG) emissions can be tracked with an extremely short time step, practically continuously, especially if the tracking is integrated with the company’s ERP1 . Furthermore, the findings show that greenhouse gas emissions from customer projects can be quantified if interpreting and implementing the GHG Protocol with a soft system methodology (SSM) approach. The thesis contributes with (1) a general interpretation of the Corporate Standard (part of the GHG Protocol) in the context of digitalization; (2) a specific example of that interpretation and implementation; (3) a practical interpretation and implementation of the Project Protocol in the context of digitalization and its avoided or caused greenhouse gas emissions; and (4) a general and an in-depth analysis on the topic of quantifying a Swedish digitalization company’s greenhouse gas emissions and feasible approaches to assumption making. / Forskning slår fast att uppvärmningen av klimatet under det senaste århundradet med extremt hög sannolikhet är orsakad av människan. Det finns ett behov att förstå hur affärsverksamheter motverkar eller bidrar till klimatförändringarna. En del av denna affärsverksamheten sker inom digitaliseringsindustrin, vilken ofta presenteras som en central spelare i klimatfrågan. Å andra sidan visar forskning även på en osäkerhet gällande digitaliseringsindustrins påverkan på klimatet eftersom den i vissa fall bidrar till klimatförändringar medan den i andra fall motverkar dem. För att förstå samspelet mellan växthusgasutsläpp och digitala lösningar är det nödvändigt att överskåda och kvantifiera utsläpp från specifika digitaliseringsprojekt och, vidare, från själva industrin. Uppsatsen grundar sig i en fallstudie på ett svenskt digitaliseringskonsultbolag för att undersöka hur både interna utsläpp och utsläpp från kundprojekt kan kvantifieras så precist och så frekvent som möjligt. Resultaten pekar på att växthusgasutsläppen kan spåras och följas med extremt kort tidssteg, i stort sett kontinuerligt, i synnerhet om spårningen kan integreras med företagets affärssystem. Dessutom visar resultaten på att växthusgasutsläpp från kundprojekt kan kvantifieras om GHG Protocol tolkas och implementeras med hjälp av en “soft systems” metod (SSM). Uppsatsen bidrar med (1) en generell tolkning av Corporate Standard (en del av GHG Protocol) i en digitaliseringskontext; (2) ett specifikt exempel på en sådan tolkning och implementering; (3) en praktisk tolkning och implementering av Project Prototcol (en del av GHG Protocol) in en kontext av digitaliseringsbranschen och dess undvikta eller orsakade utsläpp; och (4) en generell och djupgående analys angående kvantifiering av ett svenskt digitaliseringsbolags växthusgasutsläpp och gångbara inställningar till att göra antaganden.
8

The Role of the Forest in Climate Policy

Eriksson, Mathilda January 2016 (has links)
Abstract In Paper [I], I develop the FOR-DICE model to analyze optimal global forest carbon management. The FOR-DICE is a simple framework for assessing the role of the boreal, tropical, and temperate forests as both a source of renewable energy and a resource to sequester and store carbon. I find that forests play an important role in reducing global emissions, especially under ambitious climate targets. At the global level, efforts should focus on increasing the stock of forest biomass rather than increasing the use of the forest for bioenergy production. The results also highlight the important role of reducing tropical deforestation to reduce climate change. In Paper [II], I develop the FRICE to investigate the role of two key efforts to increase the stock of forest biomass, namely, afforestation and avoided deforestation. FRICE is a multi-regional integrated assessment model that captures the dynamics of forest carbon sequestration in a transparent way and allows me to investigate the allocation of these actions across space and time. I find that global climate policy can benefit considerably from afforestation and avoided deforestation in tropical regions, and in particular in Africa. Avoided deforestation is particularly effective in the short run while afforestation provides the largest emissions reductions in the medium run. This paper also highlights the importance of not solely relying on avoided deforestation as its capacity to reduce emissions is more limited than afforestation, especially under more stringent temperature targets. In Paper [III], we investigate how uncertainties linked to the forest affect the optimal climate policy. We incorporate parameter uncertainty on the intrinsic growth rate and climate effects on the forest by using the state-contingent approach. Our results show that forest uncertainty matters. We find that the importance of including forest in climate policy increases when the forest is subject to uncertainty. This occurs because optimal forest response allows us to reduce the costs associated with uncertainty. In Paper [IV], we explore the implications of asymmetries in climate policy arising from not recognizing forest carbon emissions and sequestration in the decision-making process. We show that not fully including carbon values associated with the forest will have large effects on different forest controls and lead to an increase in emissions, higher carbon prices, and lower welfare.  We further find, by investigating the relative importance of forest emissions compared to sequestration, that recognizing forest emissions from bioenergy and deforestation is especially important for climate policy.
9

Improving care delivery in critical access hospitals: evaluating the quality environment and the 'critical' role of telemedicine on access and costs

Natafgi, Nabil M. 01 May 2017 (has links)
Critical Access Hospitals (CAHs) – the predominant type of hospital operating in rural areas – play an integral role in the US healthcare system, providing care for over 7 million rural residents each year who might otherwise have no local access to urgent care or inpatient services. This dissertation examines three aspects of care delivery in CAHs – effectiveness, cost/efficiency, and access – each of which has separate implications for policy and practice. The first study addresses effectiveness and evaluates the performance of CAHs on specific patient safety indicators compared to small Prospective Payment System (PPS) hospitals. A total of 35,674 discharges from 136 non-federal general hospitals with fewer than 50 beds were included in the analyses: 14,296 from 100 CAHs and 21,378 from 36 PPS hospitals. Outcome measures included six bivariate indicators of adverse events of surgical care that were developed from Agency for Healthcare Research and Quality Patient Safety Indicators. Multiple logistic regression models were developed to examine the relationship between hospital adverse events and CAH status. The results indicated that compared to PPS hospitals, CAHs are less likely to have any observed (unadjusted) adverse event on all six indicators, four of which are statistically significant. After adjusting for patient mix and hospital characteristics, CAHs perform better on three of the six indicators. Accounting for the number of discharges eliminated the differences between CAHs and PPS hospitals in the likelihood of adverse events across all indicators except one. Tele-emergency (tele-ED) services can address several challenges facing emergency departments (EDs) in rural areas. The second study investigates access and characterizes the impact of a rural-ED-based telemedicine program on discharge disposition in terms of patient transfer, local hospital admission, and routine discharge. This study tests the hypothesis that telemedicine enhances access by allowing patients to receive care in the local community, and does so by looking at the probability of transfer and local admissions before and after telemedicine was implemented in CAHs. The results indicate that in the post-telemedicine period, patients were 38% less likely to be admitted to the local inpatient facility than to be routinely discharged [aOR=0.62, 95%CI=(0.57,0.67)] after adjusting for age, sex, race, time of visit, clinical diagnosis, CPT code, number of diagnoses, and admitting hospital. The third study addresses cost and efficiency by modeling the financial implications of using the same telemedicine program to avoid transfers and estimating the costs and benefits associated with tele-ED implementation in CAHs. Analysis is based on 9,048 tele-ED encounters generated by the Avera eEmergency program in 85 rural hospitals across seven states between October 2009 and February 2014. For each non-transfer patient, physicians indicated whether the transfer was avoided because of tele-ED activation. The cost-benefit analysis is conducted from the hospital, patient, and societal perspectives, and includes technology costs, local hospital revenues, and patient-associated savings. The results show that 1,175 avoided transfers could be attributed to tele-ED. From a rural hospital perspective, tele-ED costs around $1,739 to avoid a single transfer but saves approximately $5,563 in avoided transportation and indirect patient costs. From a societal perspective, tele-ED results in a net savings of $3,823 per avoided transfer while accounting for tele-ED technology costs, hospital revenues, and patient-associated savings. This study highlights various stakeholder perspectives on the financial impact of tele-ED in avoiding patient transfers in rural EDs. Telemedicine has the potential to reduce the number of transfers of ED patients and generate some revenue for rural hospitals despite associated technology costs, while incurring substantial patient savings.
10

Les fondements métapsychologiques de la notion d'objet autistique à partir d'une observation / Metapsychological foundations of the concept of autistic object from an observation

Desroches, Elisabeth 27 September 2016 (has links)
L'accompagnement en tant qu'auxiliaire de vie scolaire de Max, adolescent diagnostiqué autiste Asperger, fut le cadre de notre observation et de recherche clinique. Max a l'habitude d'aller toucher les cheveux d'autrui, ce que nous envisageons comme la manipulation d'un objet autistique atypique et une modalité particulière de rencontre de l'autre. À partir des travaux et des références de Francès Tustin, nous proposons une recherche à propos des fondements métapsychologiques de la notion d'objet autistique afin de déterminer quels sont les processus psychiques qui sous-tendent leur apparition. Nous étudions les cheveux en tant qu'éléments corporels symboliques et découvrons leur polysémie. Puis nous comparons la fonction et la manipulation des objets autistiques à celles des objets transitionnels, fétiches et self-objects, ce qui nous permet de penser des modalités spécifiques de relations d'objet. Notre hypothèse de la relation autistique à l'objet envisage l'émergence des objets autistiques en tant que témoins d'une relation à l'autre impossible et évitée, mais néanmoins recherchée et désirée. Cet évitement mènerait à l'intérêt pour un objet matériel. En outre, nous présentons le travail d'élaboration de notre accompagnement et de notre relation. Ainsi, l'élaboration du contre-transfert s'étaye sur une mise en dialogue de la situation d'observation et d'œuvres littéraires. Enfin, nous proposons une extension de la notion d'objet autistique et de la relation autistique à l'objet par une réflexion sur les nouvelles modalités de relation à l'autre que constituent les communications numériques. / The help I provided to Max as a school assistant was our context for the clinical research presented in this thesis. Max is a handicapped teenager diagnosed with Asperger's syndrome. He is used to touch other people's hair, which we consider as an atypical autistic object and a particular mode of meeting others. Based on Francès Tustin's work and research, we offer a study about the metapsychological foundations of the autistic object's concept to define the psychic processes underlying their appearance. We consider hair as a symbolic part of the body and found their polysemy. Then we compare the autistic object's fonction and manipulation with those of transitionnal objects, fetish objects and self-objects, which allows us to think of specific modes of object relations. Our hypothesis about autistic object relations considers the emergence of autistic objects as witnesses of an impossible and avoided relation to another, nevertheless sought and desired. This avoidance would lead to the interest for a material object. Moreover, we present the development of our study, in helping and relationship. Therefore the countertransference elaboration is based on dialogue between our observation situation and literary work. At last, we propose an extension of the autistic object concept and of the autistic object relation by reflecting on the new forms of communication with others, like digital communications.

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