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Valorisation of Mediterranean agroindustrial by-products in pig production as feed and anaerobic co-digestion of slurryFerrer Riera, Pablo 02 September 2021 (has links)
Tesis por compendio / [ES] Actualmente, la sostenibilidad del sector porcino depende de su capacidad para responder a la elevada demanda de productos ganaderos derivada del crecimiento de la población, adaptándose a los cambios en los contextos económico y político, y mejorando su rendimiento medioambiental mediante la mitigación de su impacto ambiental. En este contexto, el uso de subproductos agroindustriales ofrece materias primas alternativas en producción animal, con una menor carga ambiental asociada, en forma de piensos para el ganado, fuente de compuestos bioactivos o materias primas útiles en la producción de bioenergía.
Esta tesis doctoral pretende evaluar el uso de subproductos agroindustriales mediterráneos como ingredientes en piensos para el ganado porcino o como co-substratos para la producción de biogás. Con este objetivo, se diseñaron y realizaron cuatro ensayos para evaluar el uso de subproductos de la industria del aceite de oliva y del zumo de naranja en alimentación porcina, evaluando su valor nutricional y las consecuencias de su inclusión sobre el rendimiento y la salud de los animales, la calidad del producto final y las emisiones de gases de los purines. Además, se realizó un ensayo para evaluar el efecto de cuatro sustratos agrícolas sobre el potencial bioquímico de metano (BMP) en co-digestión anaerobia con purines.
Los resultados obtenidos a partir de los ensayos de valor nutricional indican que las tortas de aceituna y las pulpas de naranja ensayadas pueden ser incluidas en la dieta con cambios asociados en la excreción de nutrientes que conducen a modificaciones en las emisiones potenciales de amoníaco y BMP de los purines. En cuanto a los subproductos de la torta de aceituna, el ensayo de valor nutricional con tortas de aceituna crudas (COC) y parcialmente desgrasadas (PDOC) mostró que ambas tortas son fuentes apreciables de fibra insoluble, pero tienen un valor energético limitado (11.2 y 7.4 MJ/kg MS para COC y PDOC respectivamente) y un bajo valor como fuente de proteínas. En cambio, las pulpas de naranja deshidratadas (DOP) y ensilada secada al sol (ESDOP) ensayadas son una fuente de energía relevante (14.2 y 13.2 MJ/kg MS para DOP y ESDOP respectivamente) con valor añadido debido a su contenido en fibra soluble. En los ensayos de emisiones in vitro, los subproductos ensayados generaron una disminución en la excreción de N en la orina y, en el caso de la pulpa de aceituna, un aumento de la excreción de materia seca en heces. La emisión de amoniaco por kg de purín disminuyó con la inclusión de torta de aceituna y pulpa de naranja, mientras que el BMP por animal y día se vio negativamente afectado por la inclusión de torta de aceituna obteniendo un mayor BMP con estos subproductos.
En cuanto a los ensayos de rendimientos productivos, la PDOC y la DOP pueden incluirse en la dieta hasta 120 y 240 g/kg respectivamente, sin efectos negativos en el caso de la PDOC y efectos menores para la DOP sobre los rendimientos productivos, la composición corporal y la calidad de la canal. La inclusión de PDOC y DOP no afectó a los recuentos microbianos ni al volumen, la composición y la emisión global de gases de los purines. Además, se observaron efectos beneficiosos sobre la grasa subcutánea con la inclusión de PDOC, mejorando su concentración en ácido oleico.
La co-digestión anaerobia de subproductos agrícolas y purines mejora el BMP de la mezcla de sustratos en comparación con la digestión única de purines. Se obtuvieron mayores valores de BMP con la adición de los sustratos agrícolas, lo que confirma el mejor rendimiento de los sistemas en co-digestión a niveles de inclusión adecuados. Las combinaciones con tomate, pimiento y melocotón al nivel de inclusión 3 (50% de SV) alcanzaron el mayor BMP. Esto supuso un incremento del BMP del 41% con tomate, 44% con pimiento, 28% con melocotón y 12% con caqui. Los sustratos vegetales mostraron un mayor contenido en lípidos, prote / [CAT Actualment, la sostenibilitat del sector porcí depèn de la seua capacitat per a respondre a l'elevada demanda de productes ramaders derivada del creixement de la població, adaptant-se als canvis en els contextos econòmic i polític, i millorant el seu rendiment mediambiental mitjançant la mitigació del seu impacte ambiental. En aquest context, l'ús de subproductes agroindustrials ofereix matèries primeres alternatives en producció animal, amb una menor càrrega ambiental associada, en forma de pinsos per al bestiar, font de compostos bioactius o matèries primeres útils en la producció de bioenergia.
Aquesta tesi doctoral pretén avaluar l'ús de subproductes agroindustrials mediterranis com a ingredients en pinsos per al bestiar porcí o com co-substrats per a la producció de biogàs. Amb aquest objectiu, es van dissenyar i realitzar quatre assajos per a avaluar l'ús de subproductes de la indústria de l'oli d'oliva i del suc de taronja en alimentació porcina, avaluant el seu valor nutricional i les conseqüències de la seua inclusió sobre el rendiment i la salut dels animals, la qualitat del producte final i les emissions de gasos dels purins. A més, es va realitzar un assaig per a avaluar l'efecte de quatre substrats agrícoles sobre el potencial bioquímic de metà (BMP) en co-digestió anaeròbia amb purins.
Els resultats obtinguts a partir dels assajos de valor nutricional indiquen que les trotes d'oliva i les polpes de taronja assajades poden ser incloses en la dieta amb canvis associats en l'excreció de nutrients que condueixen a modificacions en les emissions potencials d'amoníac i BMP dels purins. Quant als subproductes de la torta d'oliva, l'assaig de valor nutricional amb tortes d'oliva crues (COC) i parcialment desengreixades (PDOC) va mostrar que totes dues coques són fonts apreciables de fibra insoluble, però tenen un valor energètic limitat (11.2 i 7.4 MJ/kg MS per a COC i PDOC respectivament) i un baix valor com a font de proteïnes. En canvi, les polpes de taronja deshidratades (DOP) i ensitjada assecada al sol (ESDOP) assajades són una font d'energia rellevant (14.2 i 13.2 MJ/kg MS per a DOP i ESDOP respectivament) amb valor afegit a causa del seu contingut en fibra soluble.
Pel que fa als assajos d'emissions in vitro, els subproductes assajats van generar una disminució en l'excreció de N en l'orina i, en el cas de la polpa d'oliva, un augment de l'excreció de matèria seca en femtes. L'emissió d'amoníac per kg de purí va disminuir amb la inclusió de torta d'oliva i polpa de taronja, mentre que el BMP per animal i dia es va veure negativament afectat per la inclusió de torta d'oliva obtenint un major BMP amb aquests subproductes. Quant als assajos de rendiments productius, la PDOC i la DOP poden incloure's en la dieta fins a 120 i 240 g/kg respectivament, sense efectes negatius en el cas de la PDOC i efectes menors per a la DOP sobre els rendiments productius, la composició corporal i la qualitat de la canal. La inclusió de PDOC i DOP no va afectar els recomptes microbians ni al volum, la composició i l'emissió global de gasos dels purins. A més, es van observar efectes beneficiosos sobre el greix subcutani amb la inclusió de PDOC, millorant la seua concentració en àcid oleic.
La co-digestió anaeròbia de subproductes agrícoles i purins millora el BMP de la mescla de substrats en comparació amb la digestió única de purins. Es van obtenir majors valors de BMP amb l'addició dels substrats agrícoles, la qual cosa confirma el millor rendiment dels sistemes en co-digestió a nivells d'inclusió adequats. Les combinacions amb tomaca, pimentó i bresquilla al nivell d'inclusió 3 (50% de SV) van aconseguir el major BMP. Això va suposar un increment del BMP del 41% amb tomaca, 44% amb pimentó, 28% amb bresquilla i 12% amb caqui. Els substrats vegetals van mostrar un major contingut en lípids, proteïnes, lignina i cel·lulosa que els substrats de fruita. / [EN] Nowadays the sustainability of the pig sector relies on its capability to respond to the increasing demands for livestock products that are arising from population growth, adapting to changes in the economic and policy contexts, and improving its environmental performance through the mitigation of its impact on climate. In this framework, the use of the agro-industrial by-products offers potential alternative raw materials for animal production with a lower associated environmental burden in the form of feedstuffs for livestock, source of bioactive compounds or raw materials useful in bioenergy production.
This PhD thesis aims to evaluate the use of Mediterranean agro-industrial by-products as feed ingredients for pigs or co-substrates for biogas production. To fulfil these objectives, four trials were designed and conducted to evaluate the use of olive oil and orange juice industry by-products in swine nutrition, assessing its nutritional value and the consequences of its inclusion in the diet on animals' performance and health, final product quality traits and gas emissions associated to the pig slurry. Additionally, one more trial was conducted to evaluate the effect of four agricultural substrates (tomato, pepper, peach and kaki) on the biochemical methane potential (BMP) in anaerobic co-digestion with pig slurry, focusing on the type of substrate and its inclusion level on the final substrate's mixture.
The results presented in this PhD Thesis from the nutritional value assays indicate that the olive cakes and orange pulps tested can be potentially included in pig diets with associated changes in urine and faeces nutrients excretion that leads to modifications in the potential ammonia and BMP emissions from slurries. Concerning olive cake by-products, the nutritional value assay designed to test the crude (COC) and partially defatted (PDOC) olive cakes showed that they are appreciable sources of insoluble fibre but have limited energy value (11.2 and 7.4 MJ/kg DM for COC and PDOC respectively) and a low value as protein source. On the contrary, the dehydrated (DOP) and ensiled sun-dried (ESDOP) orange pulps tested are a relevant energy source (14.2 and 13.2 MJ/kg DM for DOP and ESDOP respectively) with added value in terms of SF concentration. With respect to the in vitro potential ammonia and BMP emissions assays, the by-products tested led to a decreased N excretion in urine and, in the case of the OC, increased DM excretion in faeces. The ammonia emission per kg of slurry decreased with the inclusion of olive cake and orange pulp, whereas the BMP per animal and per day was negatively affected by the inclusion of olive cake obtaining higher BMP with these by-products.
Regarding the performance assays, the PDOC and the DOP may be included in balanced pig diets at rates of up to 120 and 240 g/kg respectively, without negative effects in the case of PDOC and minor effects for DOC on growth performance, body composition and carcass quality traits. Contrary to what was expected, the inclusion of PDOC and DOP did not affect microbial counts nor excreta volume, composition and global gas emission from the slurry. Additionally, beneficial effects on subcutaneous fat were observed with the inclusion of PDOC, improving its oleic acid concentration.
The anaerobic co-digestion of agricultural by-products and pig slurry improves the BMP from the mixture compared to only pig slurry anaerobic digestion. Higher BMP values were obtained with increasing addition of agricultural substrate, confirming the better performance of co-digestion systems at adequate inclusion levels. In fact, combinations with tomato, pepper and peach at inclusion level 3 (50% of VS) achieved the highest BMP. This resulted in an increase in BMP of 41% with tomato, 44% with pepper, 28% with peach and 12% with kaki. Vegetable substrates (pepper and tomato) showed higher lipid, protein, lignin and cellulose content than fruit substrates (kaki and peach). / Ferrer Riera, P. (2021). Valorisation of Mediterranean agroindustrial by-products in pig production as feed and anaerobic co-digestion of slurry [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/171747 / Compendio
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Produção e emissão de CH4 e CO2 associadas aos reservatórios da UHE Belo Monte, Rio Xingu (PA) / not availableAlem, Victor Amadeus Tropiano 26 April 2019 (has links)
Reservatórios de usinas hidrelétricas instalados em regiões tropicais podem representar contribuição significativa para as emissões de gases efeito estufa (GEEs) para a atmosfera. Neste contexto, é relevante desenvolver métodos para avaliação da emissão de CH4 e CO2 causada pela instalação desses empreendimentos hidrelétricos. A UHE Belo Monte no Rio Xingu (leste da Amazônia) é a terceira maior usina hidrelétrica em potencial de geração de energia do mundo. A estimativa das emissões de GEEs associadas à UHE Belo Monte é exemplo de alta relevância que pode servir de base para futuros empreendimentos previstos para serem construídos na região amazônica. Neste estudo, foram realizados experimentos de incubação de solos e de inundação de testemunho de solos das áreas dos reservatórios da UHE Belo Monte. Estes experimentos auxiliaram na compreensão da resposta do fluxo de CH4 e CO2 tanto na resolução vertical (e.g. profundidade), quanto na resolução horizontal (e.g. contexto fisiográfico). Os resultados demonstraram alta produção de CH4 e CO2 na camada superior (10 cm), a qual apresenta conteúdo orgânico mais elevado. O solo de floresta de igapó apresentou a maior taxa potencial de produção de CH4 (15,59 nmol CH4 g-1 h-1), enquanto que o solo de pasto apresentou a maior taxa de produção de CO2 (34,96 nmol CO2 g-1 h-1). As emissões médias de CH4 e CO2 para os reservatórios da UHE Belo Monte foram, respectivamente, iguais a 54 ± 60 mmol CH4 m-2d-1 e 330 ± 149 mmol CO2 m-2 d-1. Esses resultados indicam incremento no fluxo de CH4 e CO2 em relação ao fluxo natural destes gases no Rio Xingu medido antes da instalação da UHE Belo Monte. Isto permite computar as emissões de CH4 e CO2 na energia gerada para a avaliação do custo-benefício do empreendimento hidrelétrico, em termos de emissões de CH4 e CO2 para a atmosfera. Além disso, foram realizadas projeções de emissões de carbono ao longo de 100 anos de operação da UHE Belo Monte e a elaboração de modelo do balanço de massa de carbono (\"C budget\") para os reservatórios da UHE Belo Monte. Estimou-se que o impacto em emissões líquidas do empreendimento ocasionaria emissões entre 2,3 e 15,1 Tg C para o período de 100 anos. Dessa forma, espera-se que este estudo sirva de base para avaliar casos análogos, já que o plano de expansão da matriz energética brasileira considera a instalação de outras usinas hidrelétricas em rios do leste amazônico / Hydroelectric reservoirs installed in tropical regions can represent a significant contribution to greenhouse gas emissions (GHGs) to the atmosphere. In this context, it is relevant to develop methods to evaluate CH4 and CO2 emissions caused by the installation of hydroelectric reservoirs. The Belo Monte hydroelectric plant in Xingu River (eastern Amazon) is the third largest hydroelectric plant in the world in terms of installed capacity and is an example of high relevance that can serve as a study case to evaluate future hydroelectric projects planned to be built in the Amazon region. In this study, soil incubation and soil flooding experiments using samples from the Belo Monte reservoir areas were performed to understand the response of the CH4 and CO2 fluxes under impounding of the Xingu River, considering both vertical (e.g. depth) and horizontal resolution (e.g. physiographic context). The results showed a high production of CH4 and CO2 in the top layer (10 cm) of soils, due to higher organic content. The igapó forest soil presented the highest potential production rate of CH4 (15.59 nmol CH4 g -1 h -1), while pasture soil presented the highest CO2 production rate (34.96 nmol CO2 g -1 h-1). The mean fluxes of CH4 and CO2 from Belo Monte reservoirs were respectively 54.05 ± 60.73 mmol CH4 m-2 d-1 and 330.76 ± 149.83 mmol CO2 m-2 d-1. These results indicate significant increase in the CH4 and CO2 fluxes compared to the natural fluxes of CH4 and CO2 from the Xingu River before damming for construction of the Belo Monte reservoirs. This allows to calculate GHGs emissions associated with the energy generated by the Belo Monte hydroelectric plant in the first years of operation and its cost-benefit evaluation in terms of carbon emissions. In addition, carbon emission projections for the next 100 years were carried out and a model for carbon mass balance (CH4 and CO2 budget) was elaborated for the Belo Monte reservoirs. It was estimated that the net emissions of the Belo Monte reservoirs would vary from 2.3 to 15.1 Tg C for a period of 100 years. Thus, this study is expected to serve as a basis to evaluate similar cases, as the plan of expansion of Brazilian energy plans matrix considers the installation of other hydroelectric plants in rivers of eastern Amazon.
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Energy input, carbon intensity, and cost for ethanol produced from brown seaweedPhilippsen, Aaron 15 January 2013 (has links)
Brown macroalgae or brown seaweed is a promising source of ethanol that may avoid the challenges of arable land use, water use, lignin content, and the food vs. fuel debate associated with first generation and cellulosic ethanol sources; however, this promise is challenged by seaweed’s high water content, high ash content, and natural composition fluctuations. Notably, lifecycle studies of seaweed ethanol are lacking in the literature. To address this gap, a well-to-wheel model of ethanol production from farmed brown seaweed was constructed and applied to the case of Saccharina latissima farming in British Columbia (BC), Canada, to determine energy return on energy invested (EROI), carbon intensity (CI), and near shore seaweed farming production potential for seaweed ethanol and to examine the production cost of seaweed ethanol. Seaweed farming and ethanol production were modeled based on current BC farming methods and the dry grind corn ethanol production process; animal feed was included as an ethanol co-product, and co-product credits were considered. A seaweed ethanol yield calculation tool that accounts for seaweed composition was proposed, and a sensitivity study was done to examine case study data assumptions.
In the case study, seaweed ethanol had lower CI than sugarcane, wheat, and corn ethanol at 10.1 gCO2e/MJ, and it had an EROI comparable to corn ethanol at 1.78. Seaweed ethanol was potentially profitable due to significant revenue from animal feed sales; however, the market for seaweed animal feed was limited by the feed’s high sodium content. Near shore seaweed farming could meet the current demand for ethanol in BC, but world near shore ethanol potential is likely an order of magnitude lower than world ethanol production and two orders of magnitude lower than world gasoline production. Composition variation and a limited harvest season make solar thermal or geothermal seaweed drying and storage necessary for ethanol production in BC. Varying seaweed composition, solar thermal drying performance, co-product credits, the type of animal feed produced, transport distances, and seaweed farming performance in the sensitivity study gave an EROI of over 200 and a CI of -42 gCO2e/MJ in the best case and an EROI of 0.64 and CI of 33 gCO2e/MJ in the worst case. Co-product credits and the type of animal feed produced had the most significant effect overall, and the worst cases of seaweed composition and solar thermal seaweed drying system performance resulted in EROI of 0.64 and 1.0 respectively.
Brown seaweed is concluded to be a potentially profitable source of ethanol with climate benefits that surpass current ethanol sources; however, additional research into seaweed animal feed value, co-product credits, large scale seaweed conversion, and the feasibility of solar thermal or geothermal seaweed drying is required to confirm this conclusion. / Graduate
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Interpretations of concepts and implementation of negative emissions technologies (NETs) in long-term climate targets : A cross country comparison / Begreppstolkning och implementering av negativa utsläpp i långsiktiga klimatmål : En jämförelse mellan länderGren, Sofia, Sörman, Linnea January 2021 (has links)
Countries' long-term climate targets are described by different concepts who, over time, have become increasingly dependent on negative emissions technologies (NETs) in order for the targets to be reached. This thesis is a cross country comparison, examining similarities and differences in the concepts used by seven countries to express their long-term climate targets, focusing on their plans for implementing NETs. The empirical material was collected from interviews with experts from each country. Concepts in long-term climate targets can have various interpretations and there are uncertainties about what emissions that are covered within the different concepts. NETs are crucial for achieving any type of net-zero target however they are in nascent stages, except for forest management, and there are several factors affecting the possibilities to implement NETs. It is important not to focus too much on NETs to comply with the long-term climate targets, NETs should function as a complement to emissions reduction and target the unavoidable emissions. We recommend that countries clarify what emissions are included within their concept, set out specific targets for NETs and lastly put a great effort into clarifying policy instruments related to NETs. / Ländernas långsiktiga klimatmål beskrivs av olika begrepp som är beroende av negativa utsläppstekniker för att målen ska nås. Denna avhandling är en jämförelse mellan sju länder där ländernas likheter och skillnader undersöks genom deras val av begrepp och även deras planer för att implementera tekniker för att nå negativa utsläpp. Det empiriska materialet samlades in från intervjuer med experter från varje land. Begrepp i de långsiktiga klimatmålen kan ha olika tolkningar och det råder osäkerhet om vilka utsläpp som täcks upp inom de olika begreppen. Negativa utsläppstekniker är avgörande för att uppnå alla typer av netto-nollmål men de befinner sig i väldigt tidiga faser av utveckling, förutom skog som redan finns på plats och det finns flera faktorer som påverkar möjligheterna att implementera negativa utsläppstekniker. Det är viktigt att inte fokusera för mycket på negativa utsläppstekniker för att uppfylla de långsiktiga klimatmålen, de bör fungera som ett komplement till utsläppsminskning och rikta in sig på de oundvikliga utsläppen. Vi rekommenderar att länder klargör vilka utsläpp som ingår i begreppen, fastställer specifika mål för negativa utsläppstekniker och slutligen satsar mycket på att klargöra policyinstrument relaterade till negativa utsläppstekniker.
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Energy saving opportunities in residential buildings: insights from technological and building energy code perspectivesLi, Bo 21 September 2020 (has links)
The residential building sector plays an important role in combating climate change in Canada. Many energy efficiency solutions along with new building energy standards have been implemented to improve building energy performance. However, their effects on energy saving and GHG emissions reduction vary due to the complexity of the building systems and the variability of their operational conditions. This work quantifies such variability in both energy efficiency devices and building energy standards implementation, respectively.
The first study in this dissertation assesses the energy savings from sensible heat recovery in a residential apartment suite in various locations across Canada. A series of detailed building energy performance models are developed in TRNSYS. The HVAC system’s annual energy consumption is simulated and the results are compared with and without HRV for each climate zone. The results show the heating energy savings of employing the HRV vary from 17 to 34% depending on the winter climatic conditions; while, the building cooling energy use can be increased due to the undesired thermal recovery occurring in the HRV during the cooling season.
The second study investigates the free cooling potential of outside air in various Canadian cities. A series of thermal models developed using BEopt 2.8 for a hypothetical single-family house with various window-to-wall ratios and building aspect ratios simulates hourly building cooling load profiles. The free cooling potential is analyzed by comparing the maximum available and the actual usable free cooling for various building features and different climates. The results indicate that, although free cooling is widely available in most areas of Canada during the summer and shoulder seasons, only 17-42% of such free cooling is usable without the use of thermal storage.
The last study examines the effects of two building energy standards - the BC Step Code and the Passive House criteria - on reductions in residential household space heating GHG emissions under different enforcement scenarios. The space heating energy and the GHG emissions are estimated using the forecast growth of single detached households for the period from 2020 to 2032. The results show that the space heating GHG emissions can be reduced by 77% and 89%, respectively if the BC Step Code or the Passive House criteria is implemented in Canada. It is also found the impacts of energy code on GHG emission mitigation are less significant in regions where the carbon intensity of the dominant heating fuels is low. / Graduate
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Effects of Network Degradation On Energy Consumption of Mobile Cloud GamingThapa, Ashmita January 2022 (has links)
Cloud gaming over mobile networks enables players to play high-resource consuming games on low-end devices with various intrinsic restrictions such as limited battery lifetime and computational capacity. For mobile cloud gaming(MCG), the remaining battery level on the device is one of the critical factors that affect the sensitivity of user satisfaction. Thus, an android application is developed to measure the energy consumption of mobile devices that measure the power consumption of the device such that the obtained values correspond with the specific network conditions and users. The collected values are studied to identify if the energy consumption of the device is impacted by the network degradation that might occur during MCG in cellular networks. Results demonstrate that the energy consumption is at its highest when packet loss is 45% at 2ms RoundTrip Time (RTT) delay. Moreover, a qualitative study on the perceived Quality of Experience (QoE) of MCG over mobile networks is conducted and its impact on the energy consumption of the device is investigated where 31 users play a cloud-based First Person Shooter (FPS) for approximately 2 hours each. The results demonstrate the existence of the relationship between energy consumption and perceived QoE whereas negates the hypothesis of the existence of the relationship between QoE and CPU resources. In addition, to make comparisons of energy consumption of MCG with online mobile gaming (OMG), another test is carried out where each user plays another non-cloud-based FPS game and it is found that MCG is more efficient than OMG under the least energy-consuming network condition (2ms RTT delay) by 33.3% and the most energy consuming network condition (45% packet loss at 2ms RTT) by 32.7% in 4G cellular network.
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A Foucauldian–Fairclaughian Discursive Analysis of the Social Construction of ICT for Environmentally Sustainable Urban Development – the Case of European SocietyBibri, Simon Elias January 2013 (has links)
ICT has become so deeply embedded into the fabric of European society – in economic, political, and socio-cultural narratives, practices, and structures – that it has been constructed as holding tremendous untapped and inestimable potential for instigating and unleashing far-reaching societal transformation, addressing key societal challenges, and solving all societal problems. It has recently been seen, given its ubiquity, as a critical driver and powerful catalyst for sustainable urban development due to its potential to enable substantial energy savings and GHG emissions reductions in most urban sectors, especially buildings. However, related to this ubiquity, there are also a lot of visions (of limited modern applicability), hopes, myths, fallacies, and oxymora, which applies for the environmental subsystem of information society where debates focus on whether ICT can advance environmental urban sustainability. There are intricate relationships and tradeoffs among the multidimensional effects of ICT for the environment that flow mostly from the use and application of ICT – e.g. energy efficiency technology - throughout the urban sphere. Regardless, the technological orientation and framing of the sustainable city and the green economy has gained dominance in European society and become prevalent in what has come to be identified or known as the discourse of ICT for sustainable urban development (ICT4SUD). The aim of this study is to carry out a critical reading of the social construction of ICT4SUD, the underlying ideology about the ICT potential in advancing environmental urban sustainability. To achieve this aim, a Foucauldian-Faircloughian discursive approach is employed to examine the selected empirical material. This approach consists of nine stages: (1) surface descriptors and contextual elements; (2) historical-diachronic dimension; (3) epistemic and cultural frames; (4) discursive constructions and discourses; (5) social actors and framing power; (6) discursive strategies; (7) discursive mechanisms; (8) political practice, knowledge, and power; and (9) ideological standpoints.As a scholarly discourse, ICT4SUD is inherently part of and influenced by economic, societal, and political structures, and produced in social interaction. ICT4SUD is thus neither paradigmatic nor value-free, but rather socio-politically situated. It is shaped by cultural frames that are conventionalized by European society and attuned to its values, and it is a matter of a pre-intellectual space where ICT and sustainability constitute salient defining factors of the dominant configuration of knowledge, institutions, and material forces of European society. Indeed, ICT4SUD is impacted by earlier representations of reality and how they were reproduced in relation to the significance of discursive constructions of ICT and sustainability issues in the broader context of European culture. Moreover, the ICT4SUD discourse plays a major role in (re)constructing the image of the ICT industry as a social actor and in defining its identity and relation with other constituents of society, in that it is relocated new roles and attributed new societal missions. The dominant framing of the reports is clearly the one advanced by the ICT industry: it is constituted into the main definer of the represented reality. Further, positioning the ICT industry as the driver of the low-carbon city/economy aids the construction of an image of leadership in creating a low carbon society. The reports’ construction of energy efficiency technology is a powerful legitimation of the ICT industry’s views and actions. In addition, the ICT4SUD discourse is exclusionary, namely a number of facts and issues pertaining to structural, indirect, and systemic effects of ICT and the associated rebound effects are left out, concealed, or neglected. Also, the discourse is inclined to be deterministic, i.e. it postulates that ICT, supported by policy, will achieve SUD while it falls short in considering social behaviour and socio-economic relationships. It moreover tends to be rhetorical – that is, it promises environmentally SUD without really having a holistic strategy to achieve that goal. Furthermore, given the scientific discourse and the legitimation capacity of computing, climatology, and sustainability indicators, one can subsume a range of social and political effects under the category of discourse mechanisms through which ICT4SUD operates, which both show the power of discourse and potentially empower the ICT industry and its cohorts. There are different justifications for the development of energy efficiency technology in relation to decision-making processes. Plus, politics, as a consequence of its interaction with ICT4SUD, forces, though different mechanisms, the emergence and development of the ICT4SUD discourse, which is, simultaneously, influenced by the power/knowledge relations established in European society that bounds or expands its success. Finally, as to ideological reproduction, the ICT4SUD discourse reconstructs cultural claims, conveys ideological messages, and reproduces and legitimizes power structures.
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<b>GREENHOUSE GAS EMISSIONS AND TIME-USE PATTERNS UNDER WORK FROM HOME: AN ACTIVITY-BASED INDIVIDUAL-LEVEL MODEL</b>Hongyue Wu (19183129) 20 July 2024 (has links)
<p dir="ltr">Work from home (WFH) moves work into home life, reshaping the residential, workplace, and commuting activities, which further impacts greenhouse gas (GHG) emissions. Although existing work has explored individual time-use patterns under WFH, there is a lack of complete consideration of diverse activities, their durations and timelines, as well as the comparisons with traditional life at home and Work in Office (WIO). Also, existing studies have examined GHG emissions under WFH, while individual-level estimation using activity-specific data covering all major activities is lacking. In particular, limited studies explored individual time-use patterns and quantified activity-based emissions for the construction workforce. Therefore, this dissertation aims to (1) develop an activity-based individual-level model to estimate GHG emissions under WFH, (2) compare individual time-use patterns and activity-based GHG emissions between traditional life at home, WFH, and WIO to understand how WFH affects work, life, and the environment, especially for the construction workforce, and (3) propose activity-based decarbonization strategies to reduce GHG emissions. By employing the proposed model, high-resolution calculations of individual time-use patterns and activity-based emissions were achieved, revealing major activities’ durations and timing and highlighting major contributing activities to emissions under WFH. When shifting from traditional life at home to WFH, individuals reduced sleeping and leisure hours to incorporate work activity, resulting in an 11.34% reduction in GHG emissions. When comparing WFH to WIO, individuals reduced work and commuting time to include more cooking and leisure activities at home, mitigating GHG emissions by 29.11%. Demographic groups and climate regions showed different results mainly because of the varied work and household duties and the characteristics of regions. In addition, the construction workforce reduced GHG emissions by 13% and 46% under WFH compared to traditional life at home and WIO, respectively. Compared to the general public, the construction workforce had more reduction in work and commuting hours and associated emissions when shifting from WIO to WFH. The findings could help envision how WFH influences work, life, and the environment as well as assist both individuals and policymakers in achieving decarbonization and adopting low-carbon living during the work arrangement transition, which could contribute to sustainable development.</p>
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Energy Paths and Political Commitments: Their Roles in Environmental InequalityOng, Corinne 05 1900 (has links)
Decentralized renewable energy procurement has gained traction in recent years for its potential to alleviate rural energy poverty and environmental degradation in developing countries. Hence, this study investigates if deploying renewable energy can mitigate rural energy poverty in developing countries as often claimed. Because any energy regime cannot be initiated or sustained without the conviction of local political leaders, the study also evaluates the extent to which government investments in the development of renewable energy technologies and the energy sector, affect the environmental quality (i.e. greenhouse gas emissions) of developing countries. Energetic theory and environmental inequality constitute the key conceptual premises guiding this study. Ordinary least squares regression is utilized to analyze the relationship between key variables. The results reveal that as of 2010, use of renewable energy can indeed support rural electrification. Higher GNI per capita and use of conventional fuels are also positively related to rural electrification, all else equal. As for environmental degradation in 2005 and 2008, R&D investments actually tend to increase GHG emissions; procuring energy from either renewable or non-renewable sources is however, found to be environmentally detrimental, net of all other variables. Finally, some evidence is found for the role of aid funds and multilateral debt in abating GHG emissions.
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ICT Design Unsustainability & the Path toward Environmentally Sustainable TechnologiesBibri, Mohamed January 2009 (has links)
This study endeavors to investigate the negative environmental impacts of the prevailing ICT design approaches and to explore some potential remedies for ICT design unsustainability from environmental and corporate sustainability perspectives. More specifically, it aims to spotlight key environmental issues related to ICT design, including resource depletion; GHG emissions resulting from energy-intensive consumption; toxic waste disposal; and hazardous chemicals use; and also to shed light on how alternative design solutions can be devised based on environmental sustainability principles to achieve the goals of sustainable technologies. The study highlights the relationship between ICT design and sustainability and how they can symbiotically affect one another. To achieve the aim of this study, an examination was performed through an extensive literature review covering empirical, theoretical, and critical scholarship. The study draws on a variety of sources to survey the negative environmental impacts of the current mainstream ICT design approach and review the potential remedies for unsustainability of ICT design. For theory, central themes were selected for review given the synergy and integration between them as to the topic under investigation. They include: design issues; design science; design research framework for ICT; sustainability; corporate sustainability; and design and sustainability. Findings highlight the unsustainability of the current mainstream ICT design approach. Key environmental issues for consideration include: resource depletion through extracting huge amounts of material and scarce elements; energy-intensive consumption and GHG emissions, especially from ICT use phase; toxic waste disposal; and hazardous substances use. Potential remedies for ICT design unsustainability include dematerialization as an effective strategy to minimize resources depletion, de-carbonization to cut energy consumption through using efficient energy required over life cycle and renewable energy; recyclability through design with life cycle thinking (LCT) and extending ICT equipment’s operational life through reuse; mitigating hazardous chemicals through green design - low or non-noxious/less hazardous products. As to solving data center dilemma, design solutions vary from hardware and software to technological improvements and adjustments. Furthermore, corporate sustainability can be a strategic model for ICT sector to respond to environmental issues, including those associated with unsustainable ICT design. In the same vein, through adopting corporate sustainability, ICT-enabled organizations can rationalize energy usage to reduce GHG emissions, and thereby alleviating global warming. This study provides a novel approach to sustainable ICT design, highlighting unsustainability of its current mainstream practices. Review of the literature makes an advance on extant reviews of the literature by highlighting the symbiotic relationship between ICT design and environmental sustainability from both research and practice perspectives. This study adds to the body of knowledge and previous endeavours in research of ICT and sustainability. Overall, it endeavours to present contributions and avenues for further theoretical and empirical research and development. / +46704352135/+212662815009
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