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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.
41

Carbon emissions of retail channels: the limits of available policy instruments to achieve absolute reductions

Seebauer, Sebastian, Kulmer, Veronika, Bruckner, Martin, Winkler, Eva 09 1900 (has links) (PDF)
Buying the same product at the neighborhood store or at a shopping mall implies different carbon emissions. This paper quantifies carbon impacts of consumer choices of retail channel and shop location (where to buy), extending footprint assessments of product choices (what to buy). Carbon emissions of shopping situations are shown in the current situation, in a business-as-usual projection in 2020, and in policy scenarios with changed market shares of shopping situations. The analysis covers the product categories: groceries, clothing, and electronics & computers, from the shopping situations: neighborhood store, town center, discount store, shopping mall, and mail order/online selling. Stages of the product life cycle which differ between shopping situations are examined: freight transport, warehousing, store operation, and the last mile of the consumers' trip to the store. Carbon emissions of shopping situations amount to 2.7% of overall Austrian emissions in the base year. Dominant car use on the last mile substantially contributes to the overall footprint. In the business-as-usual scenario, carbon emissions from shopping situations increase by +33% until 2020, corresponding to 4.2% of the overall Austrian emissions target for 2020. Restricting shopping malls or supporting neighborhood stores could limit this increase to +25% and +20%, respectively. Facilitating online selling achieves no notable effects. The study underlines that an absolute reduction in private demand for household goods is necessary, as available policy instruments aiming at shopping situations fail to compensate the steady growth in private consumption.
42

Developing low carbon supply networks : influence, measurement, and improvement

Hu, Jialun January 2018 (has links)
Climate change has emerged as one of the most serious challenges faced by human beings. As manufacturing globalisation involves more and more emerging nations, a greater proportion of CO2 emissions is generated from developing countries. The dilemma between fast industrial development and carbon reduction makes firms in developing nations reluctant to take serious commitment and actions in CO2 emission reduction in their global manufacturing practices. From a theoretical perspective, low-carbon supply networks research is also still in its infant stage and needs more explorations and development. Therefore this research aims to address the research question: “How can supply networks in developing countries be developed to reduce carbon emission?” Especially it focuses on: • An influence process to engage companies in developing countries to reduce carbon emission • A typology of carbon emission assessments in supply networks • An initial process of implementing carbon-reduction projects in supply network The research adopts theory building approach based on multiple case studies. The units of analysis are carbon reduction project of focal firms and initiatives of Non-Government Organizations (NGO). Drawing upon the cases, this research develops a general framework for developing low-carbon supply network, including three parts namely network influence, network CO2 measurement, and network CO2 improvement (IMI), with the three process models accordingly proposed. In the ‘influence’ process, based on resource dependence theory (RDT), this research illustrates a categorization of influence choices and a typology of influence pathways, which both underpin the four-step influence procedure proposed later. In the ‘measurement’ process, this research proposes a goal-oriented carbon footprint measurement guideline. In the “improvement’ process, an initial framework to classify carbon reduction projects and implementation process model of these projects are both built based on the analysis of primary case studies and Carbon Disclosure Project (CDP) database which contains corporates’ carbon reduction practices. Overall this research makes contributions in the following aspects: (1) this research advocates IMI framework as a pathway to de-carbonize supply networks, contributing to manufacturing system’s evolution to sustainable paradigm; (2) It integrates the institutional, stakeholder and network theory in the context of de-carbonization, and extends the research scope of operations management; (3) The research contributes to life cycle assessment (LCA) literature by exploring supply network coordination during the LCA procedure; (4) The research also contributes to green supply chain literature by providing insights from firms’ de-carbonization projects in supply network. (5) In practice, the IMI three-process models can help practitioners to implement de-carbonization management, serving as a preliminary guideline to follow. The potential audience of this research can be MNCs, NGOs, government bodies, consultants, and any organization or individual who aim to change industrial system in the pursuit of climate change mitigation.
43

Computer simulation of dinosaur tracks

Falkingham, Peter Lewis January 2010 (has links)
Fossil tracks represent the only direct record of behaviour and locomotion of extinct animals. A computer model using finite element analysis (FEA) has been developed to simulate vertebrate track formation in cohesive substrates. This model has been designed for, and successfully run on, high performance computing (HPC) resources. A number of individual studies were carried out using the computer model to simulate both abstract indenters and virtual dinosaur autopodia. In addition to the simulation studies, two fossil tracks were described, including the first report of bird tracks at the Mammoth Site of Hot Springs, South Dakota (USA) and a re-description of a 'dinosaur tail drag' as the trace of a crocodilian. Using the computer model, it has been shown that in a wet, soft mud the indentation of a non-webbed virtual tridactyl foot created a resultant track with features analogous to 'webbing' between digits. This 'webbing' was a function of sediment deformation and subsequent failure in 3D, specific to rheology. Apparent webbing impressions were clearly developed only within a limited range of sediment conditions and pedal geometry. Indenter (pedal) geometry and morphology affect track depth independently of substrate and loading parameters. More complex morphologies interact with the cohesive substrate creating a lower effective load than that applied. In non-cohesive substrates such as sand, this effect is reversed, and it is the more compact morphologies that indent to a lesser degree. Virtual sauropod tracks were modelled, based on published soft tissue reconstructions of autopodia anatomy, and published mass/centre of mass estimates. It was shown that foot morphology and differential loading between fore- and hind- limbs leads to a range of substrates in which only the manus or pes are able to generate tracks. This offers a new mechanism for the formation of manus-only sauropod trackways, previously interpreted as having been made by swimming dinosaurs. A series of tracks were simulated using input data (loads, pedal morphologies) from four different dinosaurs (Brachiosaurus, Tyrannosaurus, Struthiomimus, and Edmontosaurus). The cohesive substrates used displayed a 'Goldilocks' effect, allowing the formation for tracks only for a very limited range of loads for any given foot. In addition, there was a strong bias toward larger animals, both in homogeneous and theoretically heterogeneous substrates. These findings imply that interpretations from track assemblages must consider that only a small proportion of the total fauna present may be recorded as a track assemblage due to substrate properties. The use of FEA to simulate dinosaur track formation has been shown to be successful, and offers a number of advantages over physical modelling including; consistency between experiments, specific control over input variables, rapid undertaking of repeatable experiments, and the ability to view subsurface deformation non-destructively. It is hoped that this work will lead to an increased interest in modelling tracks, and offer a quantitative method for studying fossil tracks.
44

ALTERNATE FUELS FOR ON-ROAD ENGINES AND IMPACT ON REDUCING CARBON FOOTPRINT

Vrushali Satish Deshmukh (11198994) 02 August 2021 (has links)
Variable valve actuation remains one of the most studied technologies for diesel engines for fuel benefits, efficiency improvements and emission control. The same can be implemented on natural gas engines however presence of throttle valve in the spark ignited natural gas engine leads to different set of challenges and outcomes. In this document, focus is on GT power led analyses for a mid-range natural gas engine and the VVA strategy applied is modulation of intake valve closure timing. The simulations are run for early intake valve closure and late intake valve closure, both applied independently and run for steady state conditions. The focus is on the low torque range to study the impact of IVC modulation on throttling losses for low torque region. The simulation studies showed that IVC strategies both early as well as late IVC do benefit in terms of thermal efficiency improvements by up to 3% and reduction in brake specific fuel efficiency by up to 13%.It also showed considerable reduction in pumping loop and increase in open cycle efficiency when IVC modulation is applied. Validating the model further with real on-engine data and then calibrating the existing GT power with the on-engine data to validate the conclusions drawn would be the next set of goals for this project.<div><br></div><div>Second part of this document is focused on real life testing of soy biodiesel fueled heavy duty on-road engine with modern exhaust aftertreatment system with SCR. Soybean based biodiesel remains one of the most sought-after alternate fuel and biofuel to be used in on-road engines. Burning biodiesel leads to a cleaner exhaust compared to conventional diesel as the biofuel is oxygenated fuel leading to more complete combustion and lower amount of emission species such as CO, CO2and PM in the exhaust. The experiments discussed in this document consisted of developing torque curve envelopes and steady state tests (RMC set points). Three soy biodiesel blends were studied which included B20-20% biodiesel, B50 –50% biodiesel and B100 –100% biodiesel. NOx emissions were observed to be considerably higher for B100 at engine outlet by up to80% as well as at tailpipe outlet increased by up to380%, compared to that of conventional diesel which is attributed to the thermal mechanism of NO production. The exhaust gas temperatures were observed to be lower by up to40-degreeC while the urea dosing was considerably higher by up to83% when using biodiesel blend B100.Thisresearch paves the way to testing further using varying biodiesel blends for regulation certification trials, for tuning the diesel engines for different biodiesel blends and for developing the control strategy for the existing diesel engines to accommodate biodiesel.<br><div><br></div></div>
45

A Framework for Benchmarking and Monitoring Building Construction Embodied Carbon Footprint using Building Information Models

Taveras Marte, Alba Olimpia 02 July 2014 (has links)
In recent years, the application of Life Cycle Assessment (LCA) databases has enabled architects/engineers to quantify the environmental impact of building materials for whole building analysis and comparative analyses of design alternatives. The application of building information modeling (BIM) has facilitated this process by providing designers and engineers with the detailed bill of materials required for LCA. However three limitations exist: First, LCA assessments have been limited to the design phase of a project delivery or post completion phase. Consequently, it does not help incentivize the choice of suppliers and delivery strategies that minimize the cradle-to-site impacts. Second, majority LCA tools ignore the impact of construction means and methods during the construction phase. Third, there is a lack of metrics and visualization tools that assess environmental impacts of decisions made during pre-construction and construction phase. As a result, little incentive exists for suppliers to provide embodied carbon footprint rates, and similarly, for contractors to balance project costs, schedule objectives with the corresponding environmental impact. To address these challenges, we propose and develop a new framework that applies BIM for reliable, effective benchmarking, monitoring, and visualization of embodied carbon footprint of construction projects. It comprises of a benchmarking module, and a monitoring and visualization module. In the experiments, this framework is implemented on concrete placement activities during the construction of the Center for the Arts facility at Virginia Tech. The developed framework can revolutionize construction by a) a rapid assessment and visualization of the deviations between expected and released carbon footprint, b) incentivizing contractors to request that manufacturers and suppliers gauge and share their carbon footprints as a part of contractor submittal process and c) incentivizing those construction firms that can complete their project with an overall carbon footprint rate lower than what is budgeted during the pre-construction or compared to the values from the design phase, while documenting and using the performance results as a benchmark for future similar projects. / Master of Science
46

The negative footprint illusion : När bedömningar av klimatpåverkan missleds av det miljövänliga / The negative footprint illusion : When judgement of climate impact is misled by that which is environmentally friendly

Ternerot, Simon, Piccardo, Joel January 2023 (has links)
No description available.
47

A takeoff for climate change mitigation – how to stay grounded? : A case study of Linköping University’s air travel carbon footprint reduction goal

Kipure, Unda January 2022 (has links)
The point of departure for this thesis is a case study of Linköping University and its goal to reduce air travel carbon emissions by 30% by 2024 compared to the year 2019 level. The aim of this study is to identify aspects that influence current academic work-related travel behaviour within the “Three spheres of transformation” to explore how changes on different levels would support or hinder the implementation of the air travel carbon emission reduction goal. As human activities have been distinctly linked to climate change, it can be justified to address human behaviour concerning climate change mitigation mechanisms. To fulfil the research aim, interviews with Linköping University’s employees were conducted and the results were analysed by applying the “Three spheres of transformation” framework and the main findings from the human behaviour field. Several aspects that affect travel behaviour were identified in all three spheres of transformation that are interconnected. This study concludes that such aspects as increased data availability concerning each employee’s air travel carbon footprint to increase the understanding of the current situation and the shift in academic structures, especially in such aspects as internationalization and academic networking that can determine researcher evaluation criteria, can support the implementation of the goal. In addition to that, the shift in paradigms regarding academic success and travel in general, as well as the understanding of how these drivers affect human behaviour, can significantly support the implementation of the University’s goal and ensure a long-term change.
48

Investigating the Environmental Footprint of Swedish Household Consumption / Undersökning av miljöavtrycket av svensk hushållskonsumtion

Steinegger, Tobias January 2019 (has links)
Production-based indicators show that Sweden has lower emissions per capita than other high-income countries. Nevertheless, scientific evidence points to a significant overshoot of some of the planetary boundaries, especially regarding climate change, if Swedish consumption-related emissions abroad are considered. Households are one of the key drivers behind the increasing environmental deconstruction. Studies estimate that household consumption, directly and indirectly, contributes to 51-81% of these environmental footprints. Better consumption-based indicators are therefore required to directpolicy interventions if Sweden wants to achieve its Generational Goal. The Generational Goalstates that the major environmental problems in Sweden should be solved, without increasing environmental and health problems outside Sweden’s borders. This project aimed to estimate the consumption-based environmental impacts of Sweden with the most recent available data. Furthermore, it gave valuable insights into the consumption-behaviour of Swedish households. The consumption-based calculations, based on EXIOBASE 3, estimated a carbon footprint of 94 Mt CO2-eq. for Sweden in 2011, whereas the production-based GHG-emissions were 30% lower than the actual emissions caused by Swedish consumption. The Land footprint was estimated at 333 000 km2. The material footprint showed that Sweden imported twice as much material as it exported to other countries, which led to a consumption-based material footprint of 279 000 kt. The total of 2 000 Mm3 of blue water was to 94% embodied in imported products. The results proved the importance of looking at the consumption-based environmental footprints to gain an accurate picture of the national environmental impact. Data on the Swedish household expenditure were combined with environmentally extended multiregional input-output tables to estimate the environmental footprint of Swedish households — the study identified food, housing and transportation as the expenditure categories with the highest environmental impact. According to the results, the total carbon footprint for one Swedish household in 2011 was 14 t CO2-eq., the land use amounted to 32 200 m2, the extracted materials to 431 m2, and the blue water consumption to 431 m3. The combination of household expenditures and environmentally extended input-output tables create a comprehensive picture of the consumption-based emissions and give a detailed insight into the consumption behaviour of Swedish households. These insights can further be used to design more accurate policies promoting a zero-carbon society within Sweden. / Produktionsbaserade indikatorer visar att Sverige har lägre utsläpp per capita än andra höginkomstländer. Vetenskapliga bevis tyder dock på en tydlig överskridning av några av de planetära gränserna, särskilt den gällande klimatförändringar, om svenska konsumtionsrelaterade utsläpp utomlands beaktas. Hushållen är en av de viktigaste drivkrafterna bakom ökningen av hållbarhetsrelaterade problem. Studier uppskattar att hushållens konsumtion direkt och indirekt bidrar till 51–81% av deras miljöpåverkan. Bättre konsumtionsbaserade indikatorer är därför nödvändiga för att styra politiska insatser om Sverige vill uppnå sitt generationslöfte att lösa de stora miljöproblemen i Sverige utan att öka miljö- och hälsoproblemen utanför Sveriges gränser. Detta projekt syftar till att uppskatta Sveriges konsumtionsbaserade miljöpåverkan med senast tillgängliga data. Dessutom ger uppsatsen värdefull insikt i de svenska hushållens konsumtionsbeteende. De konsumtionsbaserade beräkningarna, baserade på EXIOBASE 3, uppskattade ett koldioxidavtryck på 94 Mt CO2-ekv. under 2011 för Sverige, där deproduktionsbaserade växthusgasutsläppen var 30% lägre än de faktiska utsläppen som skapades genom svensk konsumtion. Det landmässiga fotavtrycket uppskattades till 333 000 km2. Det materiella fotavtrycket visade att Sverige importerade dubbelt så mycket material som de exporterade till andra länder, vilket ledde till ett konsumtionsbaserat materialavtryck på 279 000 kt. Det mesta av det blåa vatten som är inkorporerat i produkter importerades, hela 94% av den svenska totalen på2 000 Mm3. Resultaten visar vikten av att titta på konsumtionsbaserad miljöpåverkan för att få en exakt bild av den nationella miljöpåverkan. Data gällande svenska hushållsutgifter kombinerades med miljömässigt utökade multiregionala input-output-värden för att beräkna de svenska hushållens miljöpåverkan. Studien identifierade mat, boende och transport som utgiftskategorier med högst miljöpåverkan. Enligt resultaten så var det totala koldioxidavtrycket för ett svenskt hushåll under2011 14 t CO2-eq, markanvändningen uppgick till 32 200 m2, materialutvinningen till 29 t och den blå vattenförbrukningen till 431 m3. Kombinationen av hushållsutgifter och miljömässigt utökade input-output-tabeller ger en omfattande bild av de konsumtionsbaserade utsläppen och ger en detaljerad inblick i konsumtionsbeteendet hos svenska hushåll. Dessa insikter kan vidare användas för att utforma mer exakta policyer som främjar ett noll-kol-samhälle i Sverige.
49

Carbon Footprint Accounting Using Various Tools and Techniques, Comparison and Uncertainties

Sharma, Neha January 2010 (has links)
No description available.
50

Påverkan av koldioxidavtrycksmärkning vid val av maträtt på restaurang / The effect of carbon footprint labels on meal choice in restaurants

Lundh Haaland, Magnus, Ström, Oscar January 2017 (has links)
Livsmedelsverkets undersökningar visar att koldioxidutsläppen relaterade till livsmedelskonsumtion utgör ungefär 25 % av genomsnittssvenskens totala miljöpåverkan vilken gör den till viktig spelpjäs i att nå upp de framtida klimatmålen. För en hållbar miljöpåverkan beräknas det genomsnittliga utsläppet per person och år ligga på ett till två ton. År 2014 låg det genomsnittliga utsläppet per person i Sverige 5 gånger över den gränsen. Syftet med projektet var att besvara “Hur påverkas svenska kunders val av maträtt på en restaurang om koldioxidavtryck i form av färgkodning och km färd i bil presenteras på menyn, samt hur påverkas försäljning av markerade rätter jämfört med icke-markerade rätter?” Undersökningen genomfördes under 16 dagar i april 2017 på restaurangen Open Café i Stockholm där rätterna på menyn satts i förhållande till varandra utifrån koldioxidavtryck. Koldioxidavtrycket beräknades med eget framtagen mjukvara, mjukvaran är kopplad till en mat-klimatdatabas som utvecklats inom ramen för forskningsprojektet ”Förbättrad energirådgivning och förbättrade energivanor genom quantified self assisted advisory”. Markeringen som implementerades följde ett trafikljus system med grön markering för rätter med minst koldioxidutsläpp följt av gul och röd. Trafikljussystemet är en vanlig typ av nudging vilket är ett sätt att påverka konsumentens val vid köptillfället. Resultatet av undersökningen jämfördes med restaurangens tidigare data för att avgöra huruvida koldioxidavtrycksmärkningen haft någon påverkan på konsumentens val. Resultatet visade en statistisk signifikant ökning i försäljning av markerade rätter överlag, samt en statistisk signifikant ökad försäljning av rätter markerad med grönt för en av maträtt-kategorierna som undersöktes. Vidare visade resultatet av undersökningen på en minskning i koldioxidavtryck per servering på 2 % dock med en låg statistisk signifikans. På grund av den låga statistiska signifikansen går resultatet inte att generaliseras.

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