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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.
291

Multidisciplinary modeling for sustainable engineering design and assessment

Hanes, Rebecca J. 14 October 2015 (has links)
No description available.
292

Sustainability Assessment of U.S. Construction Sectors and Emerging Pavement Designs: An Ecologically Based Life Cycle Assessment

Kucukvar, Murat 26 July 2011 (has links)
No description available.
293

Thermodynamic input-output analysis of economic and ecological systems for sustainable engineering

Ukidwe, Nandan Uday 14 July 2005 (has links)
No description available.
294

Environmental and Risk Assessment at Multiple Scales with Application to Emerging Nanotechnologies

Khanna, Vikas 09 September 2009 (has links)
No description available.
295

An Evaluation of Flue Gas Desulfurization Gypsum for Abandoned Mine Land Reclamation

Pasini, Rachael A. 25 September 2009 (has links)
No description available.
296

Life Cycle Assessment of Paper Based Printed Circuits

Wan, Qiansu January 2017 (has links)
Printed circuit boards have been massively manufactured and wildly used in all kinds of electronic devices during people’s daily life for more than thirty years since the last century. As a highly integrated device mainly consists of silicon base, an etched copper layer and other soldered components, massive production of printed circuit boards are considered to be environmentally unfriendly due to the wet chemical manufacturing mode and lack of recycling ability. On the other hand, the newly invented ink jet printing technology enables cost-effective manufacturing of flexible, thin and disposable electrical devices, which avoid acid etching process and lead to less toxic emissions into the environment. It is important to consider life cycle analysis for quantitative environmental impact evaluation and comparison of both printed circuit boards and printed electronics to enhance the sustainability of a new technology with product design and development. This thesis first reviews the current approaches to conventional and modern printing methods, as well as the state-of-the-art analysis of sustainability and environmental assessment methodologies. In the second part, a typical ink jet printed electronic device is introduced (an active flexible cable for wearable electrocardiogram monitoring). This active cable is designed for the interconnection between bio electrodes and central medical devices for bio signal transmission. As the active cable consists of five different metal transmission traces which are formed by printing conductive ink onto paper substrates, different shielding methods are investigated to ensure high quality bio signal transmission. Specifically, the results prove that passive shielding methods can significantly decrease the cross talk between different transmission traces, enabling the transmitting of bio signals for wearable ECG monitoring. This research also explores environmental issues related to printed electronics. For the full life cycle of printed electronics, we focused not only on quantitative environmental emissions to air, fresh water, sea and industrial soil, but also on resource consumption and impacts analysis. Finally, comparative environmental performance evaluation of traditional cables and ink jet printed active cables are made to examine the environmental impact and sustainability of both technologies, and the results show the strengths and weaknesses of each technology by analysis and assessment. / <p>QC 20171205</p>
297

Life cycle assessment and structural analysis of renovation of Ulriksberg school building in Växjö

Ahaki Lakeh, Amir, Tahmasbi, Milad January 2022 (has links)
Massive volumes of hazardous emissions have been produced by the construction sector for which some adequate steps are implemented, but the rising trend of emissions can still be seen. In this thesis, the goal is to identify and analyze renovation measures from primary energy use and environmental impacts perspective, according to Boverket’s mandatory provisions and general recommendations (BBR 2018), for an old school building. Also, as a part of the study goal, the building structure is analyzed under the updated Eurocode SS-EN 90-91-96 in order to see if the building meets structural stability requirements. Life cycle assessment of the building is limited to production and construction stages, and it is used as a tool to evaluate the environmental impacts according to standard SS-EN 15978:2011. Most of the relevant data are provided by VÖFAB, in cooperation with Växjö municipality, as well as the company WSP group. The object of the thesis is an old three-story school building constructed in 1950 in Växjö, Sweden. The gross area of the building is 1,300 m2 and for renovation scenarios, building envelope components are investigated by adding new insulation materials considering two life cycle stages. In the production phase, the lowest primary energy use was 137 kWh/m2 for the scenario of using cellulose insulation material plus windows and exterior doors with a U-value of 1.1 [W/m2 K]. The lowest environmental impacts were also obtained for this scenario, with 14 kg CO2-eq/m2 global warming potential (GWP), 0.06 kg SO2-eq/m2 acidification potential (AP), and 0.06 kg NO3-eq/m2 eutrophication potential (EP). The results indicate that the share of the installation step in the primary energy use and environmental impacts during the construction phase is negligible, but the transportation role in this stage is significant. The highest global warming potential is for the scenario using cellulose insulation material plus windows and exterior doors with a U-value of 0.7 [W/m2 K] with 4.4 kg CO2-eq/m2 in the construction stage. Ultimately, the material production stage accounts for the most share of primary energy use and environmental impacts.  This research provides several renovation measures investigated by life cycle assessment resulting in performing climate declarations. Regarding the sensitivity analysis, the electricity source has a considerable effect on reducing total primary energy consumption and environmental impacts during the production phase. It is also found that the scenario utilizing cellulose insulation material with windows with a U-value of 1.1 [W/m2 K] shows the lowest total primary energy use and environmental impacts. Through analyzing the building structure, all Eurocode criteria within the serviceability limit state (SLS) and ultimate limit state (ULS) are fulfilled, and the structure is still stable when new materials are added through renovation.
298

Closing hte loop in the textile industry : An investigation of current recycling possibilities for textiles supporting circularity in integrated product and production development

Östangård, Sofia January 2022 (has links)
Textile companies are facing a grand challenge towards achieving circularity in their business models. With a growing demand by customers for more sustainable textile products and the increased worldwide attention on how much the textile industry contributes to greenhouse gas emissions and water pollutions, this challenge needs to be addressed.    Therefor the purpose of this master thesis is to investigate the state-of-art regarding recycling options and possibilities for textile industry. Recycling options both refers to how recycling is performed of textiles and how recycled materials are used. Following the aim is also to investigate if the industry’s demands on recycling options and recycled materials are aligned with what can be found from scientifically sources. Further, the study aims to explore re-cycled textile materials, and how (or if) these materials are competitive on the market.   The research questions where: [1] What criteria is important for companies when considering using recycled textile materials?   [2] What technologies are used for re-cycling of textiles today? a.     Are the textile materials that are used today supported by these recycling technologies? This thesis has used a qualitative approach through data collection. Data was collected through interviews and literature review. The interviews were conducted online, with representatives from different textile companies. The structure of the interviews was semi-structed. The literature review was performed based on the research question.   The main requirement companies had on recycled materials were related to quality and cost. The materials were expected to have the same standard as virgin materials. Two recycling technologies was identified, mechanical recycling and chemical recycling.    Limitations in this master thesis is towards recycling technologies and requirements/criteria on recycled materials set by companies. The study takes a comprehensive approach and conclusions that needs to be further investigated. / CircuTex
299

Livscykelanalys av avfallsförbränning och biogasproduktion

Lysell, Sara January 2014 (has links)
Livscykelanalys används som metod för att undersöka produkter eller tjänster från ”vaggan tillgraven”. Med hjälp av mjukvaruprogrammet SimaPro utförs en livscykelanalys på förbränning av avfall med energiutvinning. Resultatet jämförs med en livscykelanalys som utförs på biogasproduktion från matavfall, för att visa vilken av processerna som har mer positiv påverkan på miljön. Resultatet visar att förbränning av avfall bidrar till minskad miljöpåverkan med 63,9 kg CO2-ekvivalenter per ton avfall. Biogasproduktionen minskar miljöpåverkan med 11,6 kg CO2-ekvivalenter per ton matavfall. Förbränning av avfall är den behandlingsmetod som har mer positiv inverkan på växthuseffekten. Energiproduktion med avfall som bränsle är inte hållbart på lång sikt. Avfall är ett ohållbart bränsle, inom EU utförs ett aktivt arbete för att minska uppkomsten av avfall. / Life cycle assessment as a method is used to evaluate products or services from “cradle to grave”. A life cycle assessment of municipal waste incineration with energy recovery is conducted with the software SimaPro. The result is compared with life cycle assessment conducted on biogas production from food waste, the comparison shows the process with the least impact on the environment. Incineration of municipal waste contributes to reduced environmental impact with 63.9 kg CO2-equivalents per ton waste. Biogas production reduces the environmental impact with 11.6 kg CO2-equivalents per ton food waste. Incineration of municipal waste is the treatment with the least environmental impact. Power generation with waste as fuel is unsustainable long term, waste is an unsustainable fuel and the European Union is actively working to reduce the generation of waste.
300

The Environmental Impacts of Core Networks for Mobile Telecommunications. : A Study Based on the Life Cycle Assessment (LCA) of Core Network Equipment.

Pino, Albena January 2017 (has links)
No description available.

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