141 |
Capture those opinions! A synthesis analysis of the types of public attitudes measured in waste-to-energy and carbon capture and storage acceptance researchBalla, Patricia January 2023 (has links)
Waste-to-Energy incineration (WtE), coupled with Carbon Capture and Storage (CCS), especially Bioenergy with Carbon Capture and Storage (BECCS), suggest a way to simultaneously retrieve energy from the otherwise disposed waste and reduce CO2 emissions. Independent of one another, WtE, CCS, and BECCS are implemented in a few regions of the world, but their joint diffusion is uncommon in comparison. Regardless of how the future of their combined implementation unfolds, social acceptance is almost certainly expected to play a role in their diffusion. This thesis categorically identified overlaps and contrasts between factors that have been subjects of investigation in public acceptance research on WtE and CCS/BECCS’s social acceptance using Huijts et al’s (2012) energy technology acceptance framework. To allocate peer-reviewed international literature from the two fields for analysis, a systematic literature review was conducted. The results revealed that WtE and CCS/BECCS studies most commonly measured the public’s wide array of emotional experiences regarding the respective technologies and addressed their knowledge and experience with the technologies to the smallest degree. Energy technology projects are bound to attract emotionally charged responses, thus the commonality to address affect makes probing for emotional responses possible. Whereas knowledge can be difficult to measure due to its subjectivity. Factors that were commonly measured in one field but not in the other included public perceptions of fairness, trust, and climate change. The findings provided a comprehensive overview of factors to take into consideration when collecting public opinions on a WtE incineration facility that is coupled with CCS technology.
|
142 |
Absorption av koldioxid i ammoniaklösning / Absorption of carbon dioxide in ammonia solutionAndersson, Filippa, Bengtsson, Sofia, Lagergren, Jonas, Vikström, Madeleine January 2021 (has links)
Gasformig koldioxid kan absorberas i en ammoniaklösning och bilda salt. De möjliga produkterna är ammoniumvätekarbonat (NH4HCO3), ammoniumkarbamat (NH2COONH4) och ammoniumkarbonat ((NH4)2CO3). Ammoniak är gasformigt i rumstemperatur. För att förhindra avdunstning av ammoniak undersöktes det i den här rapporten om nedkylning av reaktionslösningen eller ett oljelager ovanför skulle kunna förhindra detta och därmed tillåta saltbildning i lösningen. Dessutom skulle absorptionen genomföras utan både oljelager och nedkylt förhållande för att bestämma vad som var mest effektivt för att ge ett så högt utbyte som möjligt. För bestämning av de bildade salternas sammansättning användes XRD som analysmetod. Resultatet från experimentet visade att salterna bildades i gasfasen och inget salt erhölls från vätskefasen. Orsaken till det är inte fastslagen, men tros bero på parametrar som salternas löslighet, lösningens pH, flödeshastighet på koldioxiden som gynnar ammoniakens avdunstning samt temperaturen. Utbytet från de olika försöksuppställningarna blev lågt i samtliga experiment, som högst erhölls relativt utbyte på 1,5%. Experimentet som gav högst relativt utbyte var försök vid 15% ammoniakkoncentration och koldioxidflöde på 181 ml CO2/min. Vid detta försök gjordes inga åtgärder för att förhindra ammoniakavdunstning från lösningen. Av de proverna som analyserades med XRD erhölls endast den önskade produkten med säkerhet i ett av proverna (isbad, 15 % NH3, 181 ml CO2/min). För att bestämma optimala reaktionsbetingelser krävs vidare studier.
|
143 |
Prediction of flue gas properties using artificial intelligence : Application of supervised machine learning by utilization of Near-Infrared Spectroscopy on solid biofuelsAbdirahman Hussein, Bashe, Samimi, Emran January 2022 (has links)
This degree project studies implementation and comparison of different AI models to predict (1) solid biofuel elements including carbon, hydrogen, nitrogen, and oxygen as well as moisture content, ash content, and higher heating value (HHV) of the fuel and (2) flue gas compositions such as concentration of carbon dioxide, carbon monoxide, nitrogen, nitrogen oxides, and water content using near-infrared spectroscopy and chemometric approaches. The study executes these predictions by simulating the operation of a combined heat and power plant (CHP) that is equipped with carbon capture and storage (CCS). The focus of this study is to investigate the possibility of using Near-Infrared spectroscopy (NIRs) technology to predict the emissions from a CHP plant, which can further improve the performance of the CCS system by providing the necessary fuel data in real time. The acquired NIR data is used to develop the Artificial Intelligence (AI) models using several regression algorithms including Linear regression, Gaussian process, Support Vector Machine, Artificial Neural Network, Ensemble Trees, and Tree regression. NIR data has been pre-processed using Savitzky-Golay (SG) and Multi scatter correction (MSC) techniques. Highest accuracy has been achieved for moisture content of the fuel using Exponential Gaussian Process, where an RMSE of 2.5687 and an R2-value of 0.9 has been obtained. Indeed, only a handful of regression algorithms have shown reasonable accuracy when predicting the fuel elements, where the HHV of the fuel has been predicted poorly as none of the algorithms have been able to execute the prediction successfully which leads to negative values of R2. Prediction of flue gas composition has been done resulting in reasonable accuracies for CO2 fraction with values of 0.1051 and 0.6 for RMSE and R2 respectively. Furthermore, the computational time of the algorithms has been investigated, which indicates that some of the pre-processing techniques could improve the computational time for a certain regression model, but not for all of them. It is conclusively possible to predict fuel elements and flue gas compositions based on data acquired from NIR spectroscopy. However, great effort must be put into model development including data treatment and AI model calibration to achieve desirable precision and reliable results.
|
144 |
Fair and Square? : Leading the Cultural and Creative Sectors towards Social Sustainability with the Fair Practice CodeBank, Rikke, Dogan, Hande January 2024 (has links)
Art and culture are increasingly recognised as essential components of our societal development, enriching the quality of our lives through imagination, connection, and innovation, while supporting various aspects of well-being, including health and lifelong learning. However, the professionals in the Cultural and Creative Sectors (CCS) often experience precarious employment conditions, including contract instability and limited social security. Ensuring secure work environments is not just a matter of policy—it is a fundamental human right. Opening this dialogue in the CCS, the Fair Practice Code serves as a compass emerging with the potential to lead the future direction of these sectors, initiated in the Netherlands and currently being adapted to Denmark. Given the urgency in addressing the psychosocial challenges within the CCS, this thesis offers a timely contribution, bridging the research gap between sustainability leadership and fair practice. With this study we explore stakeholders’ perceptions of the Code and how sustainability leadership actualises it, consequently examining social sustainability within the CCS. To address the research questions, an exploratory research design is employed, including semi-structured interviews with primary stakeholders within the CCS in Denmark and with complementary insights from the Netherlands to facilitate the collection of data. The study found that stakeholders in the CCS perceive sustainability as a foundation for the Fair Practice Code, with the other four values - trust, transparency, solidarity, and diversity - embedded within. Based on our findings, we present a revised compass for steering social development and two sets of recommendations to practitioners within the CCS.
|
145 |
Linguistic and computational analysis of word order and scrambling in PersianRezaei, Siamak January 2000 (has links)
This thesis discusses linguistic constraints on scrambling and flexibility in word order in spoken Persian (Farsi) and presents a computational model for efficient implementation of these constraints for a subset of Persian. Linguistic phenomena which we have studies include local scrambling, long distance scrambling, extrapolation of clauses, topicalisation, case tendancy and the discourse marker ra. The work extends previous work on Persian based on Government and Binding (GB) theory by considering the pragmatic aspects of Persian Grammar and long distance scrambling.
|
146 |
Leituras libertárias: cultura anarquista na São Paulo dos anos 1930 / Readings libertarians: anarchist culture in São Paulo 1930Parra, Lucia Silva 22 October 2013 (has links)
Este trabalho é um estudo da circulação de livros e práticas de leitura entre anarquistas atuantes na cidade de São Paulo na década de 1930. Foi analisada a formação e o desenvolvimento do acervo da biblioteca do Centro de Cultura Social (CCS). Organizado por anarquistas em 1933 e fechado em 1937 com o Golpe do Estado Novo, encerrando sua primeira fase. Sua biblioteca, neste período foi constituída por livros, jornais e documentos de militantes anarco-sindicalistas e tinha como função servir de subsídio para as atividades deste centro de cultura, como leituras comentadas, palestras, cursos e atividades teatrais. Além desta fonte de pesquisa foram usados também resenhas e anúncios de venda de livros publicados nos jornais A Lanterna e A Plebe, entre 1933 e 1935 e documentos do DEOPS/SP, tais como autos de busca e apreensão de bibliotecas particulares de anarquistas e relatórios de investigação que tratavam de circulação de livros e jornais libertários. As pesquisas sobre história dos livros e práticas de leitura de Robert Darnton foram usadas como referencial teórico. Entre os autores dos livros da antiga biblioteca do Centro de Cultura Social e das bibliotecas particulares apreendidas chamam a atenção clássicos do anarquismo como Malatesta, Proudhon, Kropotkin, Elisée Reclus, mas também autores como Marx e Trotsky. Quanto aos gêneros literários foram encontrados ensaios, crônicas, romances e poesias. No que se refere à circulação dos livros verificou-se que eram vendidos em algumas livrarias na cidade de São Paulo, através dos jornais libertários e pelos próprios militantes. Entre os anarquistas eram frequentes tanto as práticas de leituras comentadas em espaços como centros de cultura e bibliotecas populares quanto às leituras individuais de obras adquiridas através de compra e guardadas em pequenos acervos particulares / This work is a study of the circulation of books and reading practices among anarchists active in the city of São Paulo in the 1930s. We analyzed the formation and development collection of the Centro de Cultura Social (CCS) Library. This center was organized by anarchists in the year 1933 and closed in 1937 on the occasion of the Estado Novo, ending its first phase. His library in that period consisted of books, newspapers, anarcho-syndicalist militant documents and had the duty to serve as input to the center of culture activities, as commented readings, lectures, courses and theatrical activities. In addition to this source of research we also used reviews and adverts of selling published books in the newspaper A Lanterna and A Plebe, between 1933 and 1935 and DEOPS / SP documents, such as notices of search and seizure of anarchists private libraries and research reports about books circulation and newspapers libertarians. Were used as a theoretical research of Robert Darnton on the history of books and reading practices. About the authors of the books of both libraries, the old library of the Centro de Cultura Social and the private libraries seized, draw attention classic authors of anarchism as Malatesta, Proudhon, Kropotkin, Reclus Elisée, but also others like Marx and Trotsky. In the Literary genres we found essays, stories, novels and poetry. Regarding to the circulation of books, was found that some were sold in bookstores in the city of São Paulo, through newspapers libertarians and by the militants. Among the anarchists were frequent as commented reading practices on spaces like centers of culture and public libraries as the readings of individual works acquired through purchase and stored in small private collections
|
147 |
Rôles des altérations des gènes CTNNB1 et de ZNRF3 dans les carsinomes de la corticosurrénale / Roles of CTNNB1 and ZNRF3 genes alterations in the development of adrenocortical carcinomaOmeiri, Hanin 21 March 2017 (has links)
Les carcinomes de la cortico-surrénale (CCS) sont des tumeurs de mauvais pronostic et les thérapies sont encore limitées. La chirurgie reste à ce jour le seul traitement efficace. La compréhension des mécanismes de la tumorigenèse cortico-surrénalienne et l'identification des gènes et des voies de signalisation impliquées sont nécessaires pour identifier de nouvelles cibles thérapeutiques. Ces dernières années, plusieurs études de génomique ont été réalisées sur des cohortes indépendantes de CCS et ont mis en évidence l'existence de deux groupes de CCS ayant des profils d’expression génique particuliers et associés à des pronostics de survie différents. Il a aussi été identifié de fréquentes mutations touchant les gènes TP53 et CTNNB1 (β-caténine). De plus, l'activation aberrante de la voie WNT/β-caténine est associée au groupe des CCS agressifs. Enfin, des analyses des altérations génomiques par puce SNP et le séquençage de l’exome de cohortes de CCS a permis de préciser les fréquences des mutations de TP53 (~18%) et CTNNB1 (~14%) mais a aussi mis en évidence des mutations et des délétions homozygotes au niveau du gène ZNRF3 (Zinc And Ring Finger 3) dans environs 20% des CCS. ZNRF3 a été montré comme jouant un rôle de régulateur négatif de la voie WNT/β-caténine. Par conséquent, la voie de signalisation WNT/β-caténine est la voie la plus fréquemment altérée dans les CCS (~40%). L’objectif de mon projet était d’étudier comment l’activation constitutive de la voie WNT/β-caténine pouvait participer à la tumorigenèse cortico-surrénalienne, puis d'essayer de comprendre plus spécifiquement le rôle des altérations de ZNRF3 dans le développement et/ou l'agressivité des CCS. En combinant des analyses de transcriptomes de modèles cellulaires et de cohortes de CCS, nous avons établi une signature robuste cortico-surrénalienne de l'activation de la voie WNT/β-caténine. Parmi les gènes de cette signature, nous avons montré que AFF3 était une cible transcriptionnelle de la β-caténine et qu'il était capable de transmettre en partie les effets oncogèniques de la voie WNT/β-caténine dans les cellules cortico-surrénaliennes. En effet, son invalidation entraîne l'apoptose et diminue la prolifération des cellules cortico-surrénaliennes à l'image de l'invalidation de la β-caténine. La surexpression d’AFF3 altère l’organisation des speckles nucléaires et la localisation de CDK9/CyclinT1 impliqués respectivement dans l'épissage des ARNm et la transcription des gènes. ZNRF3 est le gène le plus fréquemment altéré dans les CCS alors qu'il l'est très peu dans les autres types de cancers. ZNRF3 est une E3 ubiquitin ligase qui entraîne l'internalisation et la dégradation des récepteurs Frizzleds de la voie WNT. Nous avons montré que ZNRF3 agit bien comme un gène suppresseur de tumeur dans les cellules cortico-surénaliennes humaines H295R. En effet la surexpression de ZNRF3 diminue la prolifération et augmente l’apoptose cellulaire de ces cellules. Nous avons aussi montré qu'à l'image d'autres régulateurs négatifs de la voie WNT comme AXIN2, ZNRF3 est un gène cible de la voie WNT/β-caténine dans la corticosurrénale. De manière intéressante, les altérations du gène ZNRF3 ne sont pas retrouvées dans des tumeurs présentant une forte activation de la voie de signalisation WNT/β-caténine, suggérant l'implication d'autres voies de signalisation. Nous avons identifié des partenaires protéiques de ZNRF3 par des expériences d'immunoprécipitation / spectrométrie de masse. Nous avons montré que ZNRF3 interagit avec la sous unité catalytique de la pompe NA+/K+, ATP1A1. Cette interaction altère le fonctionnement de la pompe NA+/K+ conduisant à des modifications du flux de Ca2+ intracellulaire. L'ensemble de ces travaux a permis de mieux comprendre comment la voie WNT/β-caténine participe à l'agressivité des cancers de la corticosurrénale et de montrer qu'AFF3 est essentiel pour les effets oncogéniques de cette voie. (...) / Adrenocortical carcinomas are rare tumors with poor prognostic and limited therapy. Up to now, surgery remains the only curative therapy. A better understanding of tumor biology and molecular prognostic factors would help to select relevant therapeutic targets and to develop innovative therapeutic strategies. In the last years, different genomic studies on independent cohorts of ACC have identified two subgroups of cancers with two distinguished profiles of genes expression and two different survival rates. Frequents alterations of CTNNB1 and TP53 are identified in ACC. Moreover, aberrant activation of WNT/β-catenin pathway in ACC is associated with lower overall survival. Using a combination of genomic approaches, we and others have recently analyzed independent cohorts of ACC. These works confirmed recurrent alterations in CTNNB1 (~14%) and TP53 (~18%), but also revealed new loci not previously reported to be altered in ACC. Strikingly, ZNRF3 (zinc and ring finger 3) was the most frequently altered gene (~20%). ZNRF3 encodes a protein that acts as a negative regulator of Wnt/β-catenin pathway. The Wnt/β-catenin pathway represents the most frequently altered pathway in ACC (~40%). The aim of my project was to study how the aberrant activation of WNT/β-catenin pathway could participate to adrenal tumorigenesis and then to identify more specifically the role of ZNRF3 alterations in development/aggressiness of ACC. By a combination of transcriptomic analysis on two cohorts of ACC and on H295R adrenocortical cells, we identified a list of genes whose expression is correlated to the WNT/β-catenin activation. Among these genes, we show that AFF3 is essential to mediate the effect of activation the WNT/β-catenin pathway in adrenocortical cancer. Indeed, AFF3 is a direct target gene of β-catenin and its silencing in H295R adrenocortical cells induces a decreased cell proliferation and an increased apoptosis similar to that induced by β-catenin silencing. Moreover, AFF3 overexpression altered the structure of nuclear speckles and the localization of CDK9/CyclinT1, which are respectively involved in mRNA splicing and transcription. ZNRF3 (zinc and ring finger 3) was the most frequently altered gene (20%) in ACC. ZNRF3 had never been frequently associated with other tumour types. ZNRF3 encodes a protein that had been described as cell-surface transmembrane E3 ubiquitin ligases, acting as negative regulators of Wnt/β-catenin signaling, by promoting the degradation of Wnt ligand receptors (Frizzled receptors). We show that ZNRF3 act as a tumor suppressor gene in adrenocortical cell line H295R. Indeed the overexpression of ZNRF3 decreases cell proliferation and increases apoptosis. We demonstrate also that ZNRF3 is a target gene of WNT/β-catenin pathway. ZNRF3 alterations have less effect on expression of WNT/β-catenin target genes than CTNNB1 mutations in ACC. Moreover, our results with ZNRF3 overexpression in H295R adrenocortical cells suggest that ZNRF3 is also involved in βcatenin independant-pathway(s) to mediate its effects on apoptosis. Using mass spectrometry analysis, we identified that ZNRF3 interacts with ATP1A1 (ATPase Na+/K+ Transporting Subunit Alpha 1), affecting the activity of the Na+/K+ ATPase pump in adrenocortical cells. These results provide a better understanding of the biological process of WNT/βcatenin pathway activation in ACC with AFF3 as new target of this pathway. Moreover, our data provide insight into the tumor suppressor role of ZNRF3 in ACC and uncovers an additional role of ZNRF3 on Na+/K+ ATPase pump activity.
|
148 |
Efeitos da contagem de células somáticas sobre a qualidade do leite semidesnatado e creme de leite pasteurizado / Effects of somatic cell count on the quality of pasteurized semi-skimmed and milk creamCoelho, Viviane Ribeiro Pinheiro 14 December 2009 (has links)
O objetivo deste estudo foi avaliar os efeitos dos níveis de contagem de células somáticas (CCS) sobre as características físico-químicas e microbiológicas do leite semidesnatado e do creme de leite pasteurizados, ao longo de 28 e 30 dias de estocagem sob refrigeração. As frações protéicas do leite semidesnatado e o perfil de ácidos graxos do creme de leite pasteurizados foram pesquisados nos dias 1, 7, 14, 21 e 28 e 1, 10, 20 e 30 dias após a produção de cada produto. Foram definidos três grupos experimentais com baixa (< 100.000 cél.mL-1), intermediária (400.000 a 500.000 cél.mL-1) e alta (>750.000 cél.mL-1) CCS. O leite utilizado para compor cada grupo, em quatro repetições, foi coletado na granja leiteira da Fazenda da Aeronáutica, na cidade de Pirassununga-SP. O leite in natura de cada grupo foi submetido a desnate para obtenção do creme e do leite semidesnatado, tratados termicamente por pasteurização lenta e rápida, nesta sequência, seguido do envase asséptico em garrafas de polietileno de alta densidade (PEAD). No leite in natura, o percentual de gordura foi menor (P<0,05) no grupo com baixa CCS em relação aos demais grupos. Observou-se, ainda para o leite in natura, maior teor de proteínas (3,42%) no grupo de alta CCS. Para as frações protéicas do leite semidesnatado, não foram observadas diferenças significativas (P>0,05), com exceção da β-caseína que apresentou maior concentração nos grupos de baixa e alta CCS (P<0,05). No grupo de CCS intermediária, o leite semidesnatado apresentou 8,98, 10,17 e 6,14 mg.mL-1 das frações α-caseína, β-caseína e κ-caseína, respectivamente. A participação da αS2-caseína, fração protéica verificada em menores proporções neste estudo, foi de 9,89; 10,59 e 14,97% em relação ao total de caseína, nos grupos de baixa, intermediária e alta CCS. Houve predominância dos ácidos palmítico (C16:0), esteárico (C18:0), oléico (C18:1) e mirístico (C14:0), em todos os grupos de contagem de células somáticas e nos tempos utilizados para avaliação do creme de leite. No entanto, a concentração de ácido oléico (C18:1) foi menor nos cremes com CCS intermediária e alta (P<0,05), em relação ao grupo de baixa CCS. Os ácidos saturados apresentaram variação de 53,9 a 58,1% em relação aos insaturados. Os ácidos de cadeia curta estiveram presentes no creme de leite em aproximadamente 8,15%, enquanto os de cadeia média e longa participam com cerca de 47 e 44%, respectivamente. A CCS influenciou na concentração de β-caseína do leite semidesnatado, ao passo que, no creme de leite, a diminuição do teor de ácido oléico associada ao aumento da CCS indicou maior atividade lipolítica sobre os ácidos graxos de cadeia longa durante o período de 30 dias de estocagem. / The aim of this study was to evaluate the effects of somatic cell counts (SCC) levels on the physic-chemical and microbiological characteristics of both pasteurized semi-skimmed milk and milk cream, over 28 and 30 days of refrigerated storage. The semi-skimmed milk protein fractions were checked on days 1, 7, 14, 21 and 28, whereas the pasteurized milk cream fatty acids profile was checked on days 1, 10, 20 and 30 after each production. Three experimental groups were defined with low (<100.000 cel.mL-1), intermediate (400.000 to 500.000 cel.mL-1) and high (>750.000 cel.mL-1) SCC. The milk used in each group, with four repetitions, was collected in the Air Force dairy farm in Pirassununga, São Paulo state, Brazil. The raw milk in each group was skimmed to obtain the cream, thermally treated by slow pasteurization, and the semi-skimmed milk (fast pasteurization), followed by aseptic bottling in high density polyethylene bottles. In the raw milk, significant differences were verified by the Tukey test (P<0,05) for the parameter fat in the level of low SCC in relation to the other groups. It was also observed for the raw milk a higher rate of proteins (3,42%) in the group of high SCC, while the low count group presented 2,83% protein. For the protein fractions in the pasteurized semi-skimmed milk, with an exception of the β-casein which presented statistical difference for the 5% significance level between the low and high SCC groups, no other significant differences were observed. In the intermediate SCC group the pasteurized semi-skimmed milk presented 8,98 mg.mL-1 for α-casein, 10,17 mg.mL-1 for β-casein and 6,14 mg.mL-1 for κ-casein fractions. The αs2-casein was the protein fraction with the lowest proportions in this study, with 9,89% (low SCC), 10,59% (intermediate SCC) and 14,97% (high SCC) in relation to the casein total. There was predominance of palmitic acids (C16:0), estearic (C18:0), oleic (C18:1) and miristic (C14:0) in all somatic cell counts groups and the times used to evaluate the pasteurized milk cream. However, lower levels of oleic acid (C18:1) were observed in creams with high and intermediate SCC, when compared with the lower SCC cream. The saturated acids presented variation of 53,9 to 58,1% in relation to the unsaturated ones. The short chain acids were found in the pasteurized milk cream with about 8,15%, while the ones with medium and long chains were 47% and 44% respectively. The SCC influenced the concentration of β-casein in semiskimmed milk, while the decrease in oleic acid as observed in the cream samples containing higher SCC indicated higher lipolytic activity on the long-chain fatty acid in the product during 30 days of storage.
|
149 |
Logique du temps arborescent pour la spécification et la preuve de programmesGraf, Susanne 29 February 1984 (has links) (PDF)
Nous étudions les logiques du temps arborescent en tant qu'outils de spécification et de preuve des programmes. Les différentes logiques modales et temporelles sont comparées par rapport aux deux critères suivantes: puissance d'expression et décidabilité. Cette étude porte essentiellement sur fa comparaison des logiques du temps arborescent et des logiques du temps linéaire. Ensuite, le problème de l'utilisation des logiques du temps arborescent en tant qu'outils de preuves des programmes est étudié. Nous proposons une logique pour la preuve constructive des propriétés des processus contrôlables de CCS. Cette logique est telle, que la relation de congruence induite est la congruence observationnelle de CCS
|
150 |
A Multi-Criteria Decision Analysis and Risk Assessment Model for Carbon Capture and StorageChoptiany, John, Michael, Humphries 29 November 2012 (has links)
Currently several disparate and incomplete approaches are being used to analyse and make decisions on the complex methodology of carbon capture and storage (CCS). A literature review revealed that, as CCS is a new and complex technology, there is no agreed-upon thorough assessment method for high-level CCS decisions. Therefore, a risk model addressing these weaknesses was created for assessing complex CCS decisions using a multi-criteria decision analysis approach (MCDA). The model is aimed at transparently and comprehensively assessing a wide variety of heterogeneous CCS criteria to provide insights into and to aid decision makers in making CCS-specific decisions.
The risk model includes a variety of tools to assess heterogeneous CCS criteria from the environmental, social, economic and engineering fields. The model uses decision trees, sensitivity analysis and Monte Carlo simulation in combination with utility curves and decision makers’ weights to assess decisions based on data and situational uncertainties. Elements in the model have been used elsewhere but are combined here in a novel way to address CCS decisions.
Three case studies were developed to run the model in scenarios using expert opinion, project-specific data, literature reviews, and engineering reports from Alberta, Saskatchewan and Europe. In collaboration with Alberta Innovates Technology Futures, a pilot study was conducted with CCS experts in Alberta to assess how they would rank the importance of CCS criteria to a project selection decision. The MCDA model was run using experts’ criteria weights to determine how CCS projects were ranked by different experts.
The model was well received by the CCS experts who believed that it could be adapted and commercialized to meet many CCS decision problems. The survey revealed a wide range in experts’ understanding of CCS criteria. Experts also placed more emphasis on criteria from within their field of expertise, although economic criteria dominated weights overall. The results highlight the benefit of a model that clearly demonstrates the trade-offs between projects under uncertain conditions. The survey results also revealed how simple decision analyses can be improved by including more transparent methods, interdisciplinary criteria and sensitivity analysis to produce more comprehensive assessments.
|
Page generated in 0.034 seconds