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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.
21

Measuring and Characterizing the Ecological Footprint and Life Cycle Environmental Costs of Antarctic Krill (Euphausia superba) Products

Parker, Robert 11 April 2011 (has links)
The fishery for Antarctic krill (Euphausia superba) has received considerable attention in recent years, owing largely to the possibility of its significant expansion and the ecological implications of increased extraction of a keystone species. This thesis employed Ecological Footprint (EF) analysis and life cycle assessment (LCA) to measure the resource use, energy use, and emissions associated with three krill-derived products: meal and oil for aquaculture feeds, and omega-3 krill oil capsules for the nutraceutical market. The product supply chains of one krill fishing and processing company, Aker BioMarine, were used as a case study to examine Antarctic krill-derived products. Antarctic krill products were compared to products from similar fisheries targeting other species for reduction into meal and oil, including Peruvian anchovy (Engraulis ringens), Atlantic herring (Clupea harengus), blue whiting (Micromesistius poutassou) and Gulf menhaden (Brevoortia patronus), on the basis of marine footprint, carbon footprint, and fuel use intensity.
22

Sustainable community development - impact of residents' behaviour on total sustainability of a sustainable community

Seidel, Volker Patrick 2013 (has links)
Planners and designers of sustainable communities claim they design them according to sustainability principles, but residents must also embrace those principles in their private lives in order to reduce the community's ecological footprint. One such sustainable community is the "UniverCity" on Burnaby Mountain next to the Simon Fraser University. This research investigated the influence of the residents' individual behaviour on the total ecological footprint of this sustainable community and how planners can influence their residents' behaviour. Using the UniverCity as a case study, this research demonstrates that not all sustainable community planners attempt to influence the residents' behaviour to be more sustainable and that the planners do not always measure the ecological footprint of a community. The study recommends that community planners should attempt to measure this or similar indicators and use direct and indirect influencing methods to build an active and engaged community and foster sustainable behaviour.
23

Modellering av koldioxidavtrycket för Käppalaverket med framtida processlösning för skärpta reningskrav : Modeling the carbon footprint of Käppala WWTP due to more stringent discharge limits

Erikstam, Stefan 2013 (has links)
I och med Sveriges åtaganden i Baltic Sea Action Plan (BSAP) och de miljökvalitetsnormer (MKN) som beskrivs i ramdirektivet för vatten kommer Käppalaverket sannolikt ställas inför strängare kväve- och fosforreningskrav. Käppala kan då bli tvungna att införa en ny processlösning t.ex. efterdenitrifikation och förfällning. Hur detta kommer att påverka det totala koldioxidavtrycket utreds i denna rapport. Tidigare har stora energiutredningar utförts på verket men aldrig har ett samlat koldioxidavtryck dokumenterats. En kartläggning över Käppalaverkets totala koldioxidavtryck 2011 gjordes för att skapa en referens för framtida modellering. Utvärderingen visade att Käppalaverkets totala koldioxidavtryck var 16 kg CO2,ek/pe, år. Ryaverket, som gjort en liknande utredning, hade ett totalt koldioxidavtryck runt noll. Det höga koldioxidavtrycket för Käppalaverket, jämfört med Ryaverket, beror framförallt på den höga lustgasemissionen från aktivslambassängen. Under hösten 2012 utfördes mätningar av lustgas för att få fram ett nyckeltal på bildad lustgas per reducerad kväve. Mätningarna visade på en relativt hög lusgasbildning 1,7 % bildad lustgas per reducerad kväve. För att ge svar på vad den nya processlösningen med strängare reningskrav skulle innebära för koldioxidavtrycket, kalibrerades och utvidgades den befintliga reningsverksmodellen Benchmark Simulation Model no.2 (BSM2). I utvidgningen av BSM2 inkluderades beskrivningar över hur Käppalas processer bidrar till koldioxidavtrycket. För att uppnå de nya reningskraven kan dagens fördenitrifikation kompletteras med en efterdenitrifikation och dagens simultanfällning ersättas med förfällning. Modellens biologi kalibrerades med två perioder, ett sommarflöde och ett höstflöde. Sedan simulerades 2011 för att ha ett referensvärde att jämföra framtida simuleringar med. Förfällning visade sig ge en ökad biogasproduktion som bidrog starkt till ett minskat avtryck. Däremot bidrog den ökade energiförbrukningen och lustgasemissionen i den biologiska reningen till ett ökat avtryck. Simuleringen med dagens rening gav ett koldioxidavtryck på cirka 14 kg CO2/pe, år och framtidens processlösning för ökad kväve- och fosforrening gav ett nästan dubbelt så stort avtryck, 26 kg CO2/pe, år. Kostnaden för den totala reningen uttryckt i koldioxidekvivalenter blir i framtiden 4,2 kg CO2/NRED mot dagens 2,5 kg CO2/NRED. En simulering av strängare reningskrav samt ökad flödesbelastning från dagens 440 000 pe till 700 000 pe visade på svårigheter att uppnå de nya reningskraven. Reningskraven kunde inte hållas under de högflödesperioder som uppkom under året på grund av slamflykt från eftersedimenteringarna. Utformningen av reningskraven är betydelsefull för branschen som helhet. Samtliga simuleringar visar svårigheter att hålla kvävekravet vid vårfloden. Det är därför av stor betydelse om kraven formuleras på årsbasis eller om de formuleras månadsvis för att reningsverken ska klara de nya kraven. In accordance with the Baltic Sea Action Plan (BSAP) and the EU water framework directive the Käppala waste water treatment plant (WWTP) could face more stringent discharge limits for phosphorous and nitrogen. To meet these limits Käppala has to change the treatment process, for example implement pre-precipitation and post-denitrification. The effect of more stringent discharge limits on the carbon footprint has not been studied at Käppala WWTP and will be studied in this report. In 2011 a static summary of the carbon footprint was made and serves as a reference for modeling. The evaluation showed that the total carbon footprint of Käppala was approximately 16 kg CO2/pe, yr. At the Rya WWTP in Gothenburg a similar study indicated a carbon footprint of 0 kg CO2/pe, yr. The difference between Käppala WWTP and Rya WWTP is explained by the large nitrous oxide emission from the activated sludge process at Käppala WWTP. During autumn 2012 the nitrous oxide emission was measured in one treatment line at Käppala, in order to get a standard value to use in the model. The measurements showed that 1.7 % of the removed nitrogen was emitted as nitrous oxide gas. An existing model, Benchmark Simulation Model no.2 (BSM2), was extended to model the effect on the carbon footprint with a future process configuration due to more stringent discharge limits. Every process that affects the carbon footprint was described by equations to simulate the emissions from the different treatment processes regarding energy consumption, chemical consumption and transport. In order to meet the new demands, current biological and chemical water treatment with pre- denitrification and simultaneous precipitation was substituted with combined pre and post denitrification and pre precipitation. The calibration of the model was made for two periods in 2011. When the suggested process configuration, with post-denitrification and pre-precipitation, was implemented it showed that the pre- precipitation increased the production of biogas and therefore decreased the carbon footprint. However, the increased nitrous oxide emission and the increased energy consumption due to the more stringent limits resulted in an increased footprint. A simulation of existing and future process configuration showed that the total footprint would increase from approximately 14 kg CO2/pe, year to 26 kg CO2/pe, year. The cost for the extra nitrogen removal would increase from 2.5 kg CO2/NRED to 4.2 kg CO2/NRED. The simulations showed that more stringent limits and increased load from 440 000 pe to 700 000 pe could be met at “normal” flow. At wet weather flow however, the process became unstable with high concentrations of effluent organic nitrogen as a result. A big question for the industry is the design of these new limits for phosphorous and nitrogen. It is of great importance whether the new limits are based on a yearly or monthly average.
24

Aging of Development: the Saemangeum Tideland Reclamation Project (STRP) in South Korea and Sustainable Development of the Two Townships in and out of the STRP

Choi, In Huck 2012 (has links)
Is the biggest tideland reclamation project in the world (the STRP) sustainable? Since 1991, the STRP which aims at converting mudflats into 401 km2 farmland and industrial complex has been carried out in the southwestern coast of South Korea. I designed a comparative study between two neighboring rural townships with nearly identical social and ecological features except that one is within the project area and no longer has mudflats, and the other is outside of the project area and has retained its mudflats (an important source of clams). This dissertation answers the question above by comparing, sustainable development indicators and quality of life indicators in the two townships. I expected to find that people living in the township within the project area would be more sustainable because they have gone through with the environment versus development controversy in their own villages and many of them participated in person in protests with the national/local environmental movement organizations. This study uses one of the best known consumption-based sustainable development indicators (SDIs) - Personal Ecological Footprint (PEF), combined with the ethnographic data from the two townships (Gyehwa-township and Simwon-township) – to demonstrate that the PEF values of the two townships appear to be the same and the status of quality of life is quite similar. As an explanation of the unexpected result, this study contends that the level of sustainable development of the people in the in-project area (Gyehwa-township) has been more affected by nation-wide economic development trajectory than by a major regional development project (the STRP). The first stage of the STRP - the construction of the dykes - has brought about a significant effect of displacement, which cannot be said to be sustainable. However, the total influence on sustainable development in South Korea by the STRP will be determined by the progress of the second stage - internal development.
25

The Competition and Development Trend of Ultrapure Water Systems - A Case Study of S Corporation

Huang, Kun-sheng 1 August 2011 (has links)
The number of applications and the significance of ultrapure water are increasing over time in both traditional and high-tech industries. For ultrapure water treatment and production, two important types of equipments are the green technology with Electrodeionization modules (EDI), and the traditional ion exchange resins with Mixed Beds (MB). Unfortunately, it is a concern that the highly polluting MB technology produces a large volume of waste-water during the regeneration process, but still owns around 90% market share of all ultrapure water systems. By contrast, although EDI, a high-tech green product of the latest generation, has excellent market advantages and a promising future of totally replacing MB, it grabs only around 10% market share as of 2010. Perhaps, the technology and timing for EDI to be widely applied are still premature. It is also likely that most industrial consumers do not fully understand the real value and deep impact of EDI, and cling to MB under the conventional cost-price consideration. However, it is a global trend to be environmentally friendly. For example, in recent years the world¡¦s major automobile companies have invested in developing and manufacturing hybrid/electric vehicles that are equally functional yet more costly than traditional cars. Moreover, governments counteract general consumers¡¦ preference for low-price products by imposing more stringent standards for cars¡¦ emissions and energy consumptions with the aid of new laws and subsidies. If there is a lesson to be learned here, isn¡¦t EDI to the ultrapure water industry what hybrid/electric cars are to the automobile industry in terms of their developing trends and values? This thesis will examine a specific case, S company, which manufactures EDI. Through the analysis of the company, advantages of its products, and potential opportunities in its business environment, empirically it can be shown that EDI will inevitably become the mainstream in the future market by gradually replacing all traditional MB. Hopefully such an empirical conclusion would inspire and educate industrial manufacturers to make their future choices between EDI and traditional MB based not only on the operating efficiency, but also on which technology contributes more to environmental protection and earth sustainability during the development of an enterprise. It is also of hope that the perspective on system designs and usages could be more objective and unbiased. For instance, instead of always chasing low costs as the first priority in the pursuit of profits and development, enterprises could take into account social responsibilities, such as environment protection, energy conservation, and carbon reduction, and become pioneers in carbon footprint reduction.
26

Software-related Energy Footprint of a Wireless Broadband Module

Asplund, Mikael, Thomasson, Anton, Vergara Alonso, Ekhiotz Jon, Nadjm-Tehrani, Simin 2011 (has links)
Energy economy in mobile devices is becoming an increasinglyimportant factor as the devices become more advancedand rich in features. A large part of the energy footprint of amobile device comes from the wireless communication module,and even more so as the amount of trac increases.In this paper we study the energy footprint of a mobilebroadband hardware module, and how it is aected by software,by performing systematic power consumption measurements.We show that there are several cases where thesoftware does not properly take into account the eect thatdata communication has on the power consumption. Thisopens up for potential energy savings by creating better applicationsthat are aware of the energy characteristics of thecommunication layer.
27

WATER FOOTPRINT OF AVIATION FUEL SYNTHESIS BY THE FISCHER TROPSCH PROCESS USING SUGAR CANE WASTE & LANDFILL GAS AS FEEDSTOCKS

Menzli, Slim 1 January 2008 (has links)
The recent spikes in oil prices have spurred an already bullish demand on biofuels as a source of alternative energy. However, the unprecedented price records set simultaneously by staple food have raised high concerns about potential impacts of biofuels on the global agricultural landscape as fuel and food markets are being inextricably coupled. The revival of interest in the Fischer-Tropsch (FT) process comes into full force since it offers a promising way to produce carbon-neutral liquid fuels which are readily usable with today's existing infrastructure. The FT synthesis offers the possibility of using crop waste as feedstock instead of the crop itself thus avoiding the risk of further straining water and land resources while helping to alleviate the national energy bill and to achieve independence from foreign oil. As the airline industry is the hardest-hit sector with fuel jumping ahead of labor as the primary cost item, this thesis investigates the prospects of the FT process to transform sugar cane waste (namely bagasse, tops and green leaves) and landfill gas in order to produce kerosene (C12H26) as jet fuel for civil aviation. Established chemical correlations and thermodynamics of chemical reactions are used to assess the water footprint inherent to kerosene production using the above feedstocks at optimal conditions of temperature, pressure, catalyst and reactor type. It has been estimated that 9 to 19 gallons of water are needed for every gallon of kerosene produced. In addition, for the case of sugar cane, less land area per unit energy is required compared to ethanol production since all non-food waste of the plant can be used to produce FT fuel as opposed to ethanol which would utilize only the sugar (food) portion of the plant. This translates into a much lower water footprint for irrigation and consequently a lower water footprint overall. M.S.M.E. Department of Mechanical, Materials and Aerospace Engineering; Engineering and Computer Science Mechanical Engineering MSME
28

Global Systems, Local Impacts: A Spatially-Explicit Water Footprint and Virtual Trade Assessment of Brazilian Soy Production

Flach, Rafaela 2015 (has links)
Global trade and increasing food demand are important drivers of impacts in the water system across scales. This study coupled a spatially-explicit physical account of trade between Brazilian municipalities with a water footprint accounting model, in order to analyse water footprints of Brazilian soy produced for domestic and international consumption, and assess their relevance in the context of water scarcity and competing demands for water resources. The water footprints of Brazilian soy production were assessed for different levels of spatial-explicitness for comparison. The Swedish water footprints were analysed within this framework to illustrate the use of the methodology. As a result, temporal and geographical patterns of variability of water the footprints related to Brazilian soy production, attributed to different consumers in the global market, were identified. The study found the methodology to unveil important processes connected to economic and trade drivers, as well as to variability in climate and production yields. It was found that important regional variability was not considered or fully understood when accounting for water footprints as a national aggregate. Opportunities for improvement and further research were also discussed.
29

Memory Footprint Reduction of Operating System Kernels

He, Haifeng 2009 (has links)
As the complexity of embedded systems grows, there is an increasing use of operating systems (OSes) in embedded devices, such as mobile phones, media players and other consumer electronics. Despite their convenience and flexibility, such operating systems can be overly general and contain features and code that are not needed in every application context, which incurs unnecessary performance overheads. In most embedded systems, resources, such as processing power, available memory, and power consumption, are strictly constrained. In particular, the amount of memory on embedded devices is often very limited. This, together with the popular usage of operating systems in embedded devices, makes it important to reduce the memory footprint of operating systems. This dissertation addresses this challenge and presents automated ways to reduce the memory footprint of OS kernels for embedded systems. First, we present kernel code compaction, an automated approach that reduces the code size of an OS kernel statically by removing unused functionality. OS kernel code tends to be different from ordinary application code, including the presence of a significant amount of hand-written assembly code, multiple entry points, implicit control flow paths involving interrupt handlers, and frequent indirect control flow via function pointers. We use a novel "approximated compilation" technique to apply source-level pointer analysis to hand-written assembly code. A prototype implementation of our idea on an Intel x86 platform and a minimally configured Linux kernel obtains a code size reduction of close to 24%.Even though code compaction can remove a portion of the entire OS kernel code, when exercised with typical embedded benchmarks, such as MiBench, most kernel code is executed infrequently if at all. Our second contribution is on-demand code loading, an automated approach that keeps the rarely used code on secondary storage and loads it into main memory only when it is needed. In order to minimize the overhead of code loading, a greedy node-coalescing algorithm is proposed to group closely related code together. The experimental results show that this approach can reduce memory requirements for the Linux kernel code by about 53%with little degradation in performance. Last, we describe dynamic data structure compression, an approach that reduces the runtime memory footprint of dynamic data structures in an OS kernel. A prototype implementation for the Linux kernel reduces the memory consumption of the slab allocators in Linux by 17.5%when running the MediaBench suite while incurring only minimal increases in execution time (1.9%).
30

Supporting manufacturing reallocation decisions

Valciukaite, Diana, Mesinovic, Orhan 2016 (has links)
During past decades manufacturing companies started opening new plants and transfer their manufacturing to other countries in order to increase their competitiveness in the market. An important area in today’s complex business environment became manufacturing location decisions that have a direct impact on companies’ future success. Many scholars introduced suggestions in what factors should be considered in manufacturing location decisions when opening new plants. However, less research has been done by identifying what critical factors should be considered in manufacturing reallocation[1] decisions when a company operates within a manufacturing footprint and intends to move manufacturing activities between existing plants. In order to fulfil this gap the study was conducted by developing a conceptual framework for supporting manufacturing reallocation decisions. The main factors, evaluation and effects were explored. In order to conduct the study three cases were analysed in two Swedish manufacturing companies, where one of the companies was currently executing a manufacturing reallocation to another plant. It was found that sometimes companies are forced to reallocate manufacturing unwillingly due to currency value changes or local governmental regulations. A tendency was noticed that some of the factors are considered at the strategic level and some are left to be handled at the operational level. However, operational level factors have a great impact on the long term strategy and future costs and should be included when making manufacturing reallocation decisions. The evaluation of factors is mostly based on assumptions and intuition. Only evaluations of economic factors are based on facts. Improvements of economic factors’ evaluations could be made by closer collaboration between plants and involvement of the right people at the right time during data collection before making a decision. Manufacturing reallocations could have effects on the sending plant and long term strategy that increases the importance to include it during decision making since hidden costs and future risks could be prevented. Finally, the conceptual framework for manufacturing reallocations is presented that could be used as a support for manufacturing reallocation decisions. [1] to assign or allot to a different place from the one originally intended.

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