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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.
121

Medial Gestures. On the 'decipherability' of techno-images (Vilém Flusser) and their production

Büscher, Barbara 12 July 2017 (has links)
Of the plethora of observations and contextualizations that Vilém Flusser puts forward in his book Gestures (Flusser 2014), I am interested here, and with respect to current research on archival processes relating to performative arts, in his approach to media theory in particular. This is manifest in the section of the book titled “Beyond Machines” and in the three chapters devoted to the gestures that produce “techno-images”, as Flusser himself dubbed them in a previous work (Flusser 1998b: 9-234): the gestures of photographing, filming and video.
122

Application of Techno-Ecological Synergies in Life Cycle Assessment (TES-LCA) to soybean-based biodiesel

Zhao, Ruonan 29 August 2019 (has links)
No description available.
123

THE EFFECTS OF CANOPY DENSITY AND SPACING IN MODULATING POLLUTION DEPOSITION RATE

Yazbeck, Theresia January 2019 (has links)
No description available.
124

Technical, economic, and carbon dioxide emission analyses of managing anaerobically digested sewage sludge through hydrothermal carbonization

Huezo Sanchez, Luis 21 September 2020 (has links)
No description available.
125

Practical implementation of Bio-CCS in Uppsala : A techno-economic assessment

Djurberg, Robert January 2020 (has links)
To decrease global warming, bioenergy with carbon capture and storage (Bio-CCS) has been proposed as an effective and necessary tool. Combusting biomass and capturing carbon dioxide (CO2) from the same process results in net negative emissions, hence, reducing the concentration of CO2 in the atmosphere. The infrastructure around heat and power generation in Sweden has transformed to make use of biomass and waste. Bio-CCS has the potential to be a key factor in making the heat sector carbon negative and the Swedish energy system more sustainable. This study has assessed how Bio-CCS can practically be implemented in the Uppsala heat and power plant. In the assessment, three chemical absorption post-combustion carbon capture (CC) technologies were evaluated based on energy requirement, potential to reduce emissions and economics. They are the amine process, the chilled ammonia process (CAP) and the hot potassium carbonate process (HPC). The process of each technology was modelled by performing mass and energy balance calculations when implementing CC on the flue gas streams of the production units using biomass-based fuel at the plant. The modelling enabled finding specific heating, cooling and electricity requirements of the technologies. With this data it was possible to assess the potential emission reduction and CC cost for the different configurations assessed. A solution was proposed in how a CC technology can be integrated into the system of the Uppsala plant regarding land footprint, available heat supply to the process and possibilities for waste heat recovery. If heat recovery is not utilized the results show that the amine process is the most cost-effective technology when implemented on the flue gas stream of the waste blocks. When utilizing heat recovery to use waste heat to heat the district heating water, CAP becomes more cost-effective than the amine process. Further improvements can be achieved by combining flue gas streams of the waste blocks to increase the number of hours per year CC can be performed. The plant in Uppsala can then capture 200 000 tonne CO2 annually. The total cost of Bio-CCS will be approximately 900 SEK per tonne CO2 captured. / För att minska den globala uppvärmningen har infångning och lagring av koldioxid från förbränning av biomassa (Bio-CCS) föreslagits som ett effektivt och nödvändigt verktyg. Förbränning av biomassa och infångande av koldioxid från samma process leder till negativa nettoutsläpp, vilket minskar koncentrationen av koldioxid (CO2) i atmosfären. Infrastrukturen kring värme- och kraftproduktion i Sverige har omvandlats till att använda biomassa och avfall. Bio-CCS har potential att vara en nyckelfaktor för att göra värmesektorn koldioxidnegativ och det svenska energisystemet mer hållbart. Denna studie har analyserat hur Bio-CCS praktiskt kan implementeras i Uppsalas kraftvärmeverk. I analysen utvärderades tre infångningstekniker av typen kemisk absorption baserat på energibehov, potential att minska utsläpp och ekonomi. Teknikerna är aminprocessen, chilled ammonia process (CAP) och hot potassium carbonate process (HPC). Processen för varje teknik modellerades genom att utföra mass- och energibalansberäkningar vid infångning av CO2 från rökgasströmmarna producerade av produktionsenheterna som förbränner biomassa. Modelleringen gjorde det möjligt att hitta specifika värme-, kyl- och elbehov för teknikerna. Med dessa data var det möjligt att bedöma den potentiella utsläppsminskningen och kostnaden för infångning för de olika konfigurationer som har analyserats. En lösning föreslogs i hur en infångningsanläggning kan integreras i kraftvärmeverkets system när det gäller markanvändning, tillgänglig värmeförsörjning till processen och möjligheter till återvinning av spillvärme. Om värmeåtervinning inte utnyttjas visar resultaten att aminprocessen är den mest kostnadseffektiva tekniken när den implementeras på rökgasströmmen från avfallsblocken. När man använder värmeåtervinning för att använda spillvärme för att värma fjärrvärmevattnet blir CAP mer kostnadseffektivt än aminprocessen. Ytterligare förbättringar kan uppnås genom att kombinera rökgasströmmar från avfallsblocken för att öka antalet timmar per år infångning kan utföras. Anläggningen i Uppsala kan då årligen fånga 200 000 ton CO2. Den totala kostnaden för Bio-CCS kommer att vara cirka 900 SEK per ton infångad CO2.
126

Techno-Economic Analysis and Optimization of Distributed Energy Systems

Zhang, Jian 10 August 2018 (has links)
As a promising approach for sustainable development, distributed energy systems have receive increasing attention worldwide and have become a key topic explored by researchers in the areas of building energy systems and smart grid. In line with this research trend, this dissertation presents a techno-economic analysis and optimization of distributed energy systems including combined heat and power (CHP), photovoltaics (PV), battery energy storage (BES), and thermal energy storage (TES) for commercial buildings. First, the techno-economic performance of the CHP system is analyzed and evaluated for four building types including hospital, large office, large hotel, and secondary school, located in different U.S. regions. The energy consumption of each building is obtained by EnergyPlus simulation software. The simulation models of CHP system are established for each building type. From the simulation results, the payback period (PBP) of the CHP system in different locations is calculated. The parameters that have an influence on the PBP of the CHP system are analyzed. Second, PV system and integrated PV and BES (PV-BES) system are investigated for several commercial building types, respectively. The effects of the variation in key parameters, such as PV system capacity, capital cost of PV, sell back ratio, battery capacity, and capital cost of battery, on the performance of PV and/or PV-BES system are explored. Finally, subsystems in previous chapters (CHP, PV, and BES) along with TES system are integrated together based on a proposed control strategy to meet the electric and thermal energy demand of commercial buildings (i.e., hospital and large hotel). A multi-objective particle swarm optimization (PSO) is conducted to determine the optimal size of each subsystem with the objective to minimize the payback period and maximize the reduction of carbon dioxide emissions. The results reveal how the key factors affect the performance of distributed energy system and demonstrate the proposed optimization can be effectively utilized to obtain an optimized design of distributed energy systems that can get a tradeoff between the environmental and economic impacts for different buildings.
127

Feasibility of Whole-plant Corn Logistics for Biobased Industries

Khanal, Asmita 10 August 2022 (has links)
No description available.
128

Techno-Economic and Life Cycle Analysis of Phosphorus Circularity schemes in Agriculture

Sen, Amrita 04 October 2021 (has links)
No description available.
129

”Du måste vara i den röken för att förstå” - Klubbkultur: En subkulturs framväxt i det tidiga nittiotalets Malmö. ”You’ve got to be in that smoke to understand” Club Culture: The emergence of a subculture in Malmö early nineties

Herbert, Johannes January 2014 (has links)
Denna undersöknings syfte har varit att utreda när och hur subkulturen klubbkultur växte fram i Malmö, vilka som tog den hit, vad som då definierade kulturen och hur detta skiljer sig från idag.Ytterligare syfte har varit att undersöka hur klubbkulturen som sägs genomsyras av en universal jämlikhet, på olika sätt, såväl inkluderat som exkluderat människor från att delta i den. Genom kvalitativa intervjuer med sju aktörer aktiva inom klubbkulturen under det sena åttiotalet och tidiga nittiotalet, men också genom min egen bakgrund som besökare, arrangör och DJ, målar detta arbete med hjälp av muntlig historia, ett kulturanalytiskt perspektiv och med Sarah Thorntons teorier om klubbkultur och subkulturellt kapital upp historien av hur Malmös klubbkultur växt fram samt de viktiga faktorer som definierade den och på vilka sätt kulturen både exkluderade och inkluderade. Resultatet berättar en historia om en ny upprorisk motkultur som under det tidiga nittiotalet utvecklades från att ha varit en brett inkluderande, men samtidigt en underjordisk gör-det-själv-kultur, till att bland annat genom tyst exkludering i form av nischade smakgemenskaper och konsumtionssymboler, utvecklas till en uppdelad kultur som inte bara positionerade sig mot det så kallade mainstreamsamhället utan även mot andra klubbkulturer.
130

Value-Added Opportunities for Tomato and Peach Seeds

Lavenburg, Valerie Michelle 01 April 2022 (has links) (PDF)
The food industry is increasingly concerned with operational sustainability and food waste reduction. In the United States, the tomato industry was worth $1 billion in 2020, and tomatoes are currently ranked second as the most consumed vegetable after potatoes. Tomato processors have striven to valorize pomace by-products, which contain seeds with valuable compounds such as 45% fiber, 30% oil, and 26% protein. The U.S. peach industry, which was worth $599 million in 2017, is also looking for alternative ways to utilize their seeds, made up of 52% oil. Both tomato and peach seeds are rich in bioactive compounds such as carotenoids and polyphenols, respectively. Meanwhile, global edible oil production is forecasted to reach 632 million tons in 2022, and there is increasing interest to produce specialty oils. Organic solvent extractions are commonly used to extract oils from various commodities in the food industry, but this method comes with some environmental concerns, such as toxicity and flammability. Enzyme-assisted aqueous extractions (EAEP) have been proposed as a green alternative to solvent extractions of oilseeds. However, research on the economic feasibility of this process has been limited. There is a need for a better understanding of the potential of EAEP and performing such analysis on peach and tomato seeds would be valuable based on the importance of these commodities in California and in the U.S. in general. To determine whether applying such a process to tomato and peach seeds would be valuable, data on oil yields from EAEP, quality of the extracted oils, and economics associated with EAEP is needed. The U.S. snack food industry was worth approximately $42 billion as of 2019, and this market continues to grow as an increasing number of people eat snacks as meal replacements. There is also growing consumer demand for natural and functional foods, which offer health benefits beyond basic nutritional value, such as reducing risk of disease. Therefore, this consumer landscape provides excellent opportunities for by-products from vegetable and fruit processing to be transformed into functional ingredients. With these key ideas in mind, the objectives of this research were 1) to determine the impact of various extraction factors on oil yields from EAEP of tomato and peach seeds; 2) to evaluate the effect of aqueous extractions on oil quality; 3) study whether these processing steps are economically feasible for industrial commercialization and 4) identify another potential use for tomato pomace as a functional ingredient in snack food application. Tomato and peach seeds were each isolated and ground into a flour, then analyzed for fiber, fat, protein, moisture, and ash content. The effects of pH (set to 3, 9, and sequential adjustment of 3 followed by 9), time (2–8 h), and addition of cellulase, protease, and 1:1 enzymatic cocktail at a concentration of 4% were evaluated during aqueous extractions of tomato oils. Peach oil extractions were evaluated for the same parameters except for time which was fixed at 2 h. The impact of the pH of aqueous extractions on the oxidative stability and nutritional composition of tomato and peach oils were also determined. Techno-economic analyses were conducted using Superpro software to estimate operational costs and profits from this process. To assess the value of tomato by-product as a functional ingredient, pomace flour was added to crisp snacks at usage levels of 0 and 7% (w/w flour basis). Crisp snacks were stored at ambient room temperature and frozen temperatures (-23 °C) for ten weeks. Proximate analyses on the crisp snacks were conducted. Sensory evaluation was performed over time using hedonic scoring surveys. For tomato seeds, the highest oil yield (41%) was obtained during 2 h extractions at pH 9, which were 68% higher than from 2 h extractions performed at pH 3. Enzyme addition was only beneficial during 8 h extractions of tomato seeds using 4% cellulase at pH 3, which led to 53% higher oil yield compared to the control performed in the same conditions without enzymes. Increasing incubation time from 2 to 8 h improved oil yields by 63% for cellulase extractions at pH 3 and 69% for protease extractions at pH 9. Peach oil yield of the controls at pH 9 (53%) and the yield obtained with protease extractions at pH 9 (45%) were approximately eight times higher than all extractions set to pH 3. Once extracted, some properties of the tomato and peach oils were determined. The pH of the aqueous extractions did not have a significant effect on quality parameters on both tomato and peach oils, except for polyphenol content, DPPH production, peroxide and TBARS values. Overall, both tomato and peach oils had peroxide and free fatty acid values comparable to other specialty oils, such as sunflower and sesame oils. From a techno-economic point of view, tomato oil production at flow rate of 1,752,000 kg pomace/yr garnered $13 million in profit (equivalent to $7.42/kg pomace) after a payback time of 1.6 years, which was more profitable than the industry’s current pomace disposal practice. Peach oil processing became profitable once the production scale reached 65,700,000 kg pits/yr, which led to $15.5 million in profit ($0.24/kg pits). Overall, production of tomato oil was more profitable than peach oil. When tomato pomace was added into crisp snacks at 7% concentration, fiber increased by 35.2% compared to the control. Moisture content and water activity for the control and pomace crisp snacks remained constant during room temperature and frozen storage for ten weeks. However, the addition of tomato pomace led to a bitter aftertaste of the crisp snacks and reduced overall liking scores by panelists compared to scores for the control crisp snacks. Overall, this research took multiple, innovative approaches to valorize tomato and peach seeds, while also studying the economic, environmental, and industrial implications of such approaches. It highlighted alternative, sustainable strategies of how tomato and peach by-products could be repurposed to reduce waste and make value-added food products.

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