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Dissertations / Theses on the topic 'Engineering economy'
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1
Tezcakar, Merve. "Techno-economic transition towards a hydrogen economy." Thesis, Queen Mary, University of London, 2010. http://qmro.qmul.ac.uk/xmlui/handle/123456789/407.
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The research conducted is in the field of innovation and focuses on the UK energy sector. The key theme of the study is the transition towards a hydrogen economy with fuel cell technologies at the epicentre and takes into account the relevant scientific, technological, economic and policy issues. In order to provide an understanding of the factors that affect techno-economic transitions to alternative energy systems, the thesis investigates the historical transition processes such as the transition to electrification in the early 1900s and recent transitions to CCGT and renewable energy systems (wind, biofuels and solar) that have taken place since the late 1980s. As the developmental status of hydrogen technologies lay at the heart of these transitions, a thorough analysis of the hydrogen and fuel cell technologies, the R&D requirements, and innovations required in different scientific fields (including materials science) to develop these technologies is conducted. At the same time, as other factors such as sustainability, climate change and security of supply concerns can greatly affect the direction of the transition processes, that includes R&D activities and investment in alternative energy technologies, an overview of these factors is also provided. The analysis employs a new theoretical framework that combines two well established theories in the literature, Techno-economic Transitions and Large Technological Systems. By using this new framework, the technological transition towards a hydrogen energy system can be analysed at three levels, (global, national and local). The analysis is narrowed down to the local level in order to determine the timing of a transition in London and how it can form the foundation for a wider a transition at the national level based on alternative technologies.
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au, dweston@ncwa com, and Delys Eleanor Weston. "Democracy and political economy of genetic engineering." Murdoch University, 2007. http://wwwlib.murdoch.edu.au/adt/browse/view/adt-MU20070327.143205.
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This thesis aims to provide a more critical framework for the assessment of future technologies and therefore social directions and to help to bring an understanding to the relationship between global political economy, corporate power, ideology, science and technology. This is essential given the many issues facing contemporary society issues of sustainability and humanitys place in the broad ecology, of the need for a diversity of economies, societies and cultures, of the need for greater economic equality and equity across the globe.
The relationship between globalisation, science and technology, democratic governance and citizens is explored using the case of genetic engineering technologies. The thesis draws on a conceptual framework provided by the theory of political economy to facilitate the assessment of the impact of a technology on society . It provides a critical framework for looking at individualised, sectoral and short term interests versus the often conflicting interests of what is termed the common good. The juxtaposition of the neo-liberal, conservative and contemporarily dominant world view with that of the more radical, political economy stance exposes the tension between these two ways of viewing human history and the future of humankind.
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Weston, Delys E. "Democracy and political economy of genetic engineering /." Access via Murdoch University Digital Theses Project, 2007. http://wwwlib.murdoch.edu.au/adt/browse/view/adt-MU20070327.143205.
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Weston, Delys Eleanor. "Democracy and political economy of genetic engineering." Thesis, Weston, Delys Eleanor (2007) Democracy and political economy of genetic engineering. Masters by Research thesis, Murdoch University, 2007. https://researchrepository.murdoch.edu.au/id/eprint/397/.
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This thesis aims to provide a more critical framework for the assessment of future technologies and therefore social directions and to help to bring an understanding to the relationship between global political economy, corporate power, ideology, science and technology. This is essential given the many issues facing contemporary society - issues of sustainability and humanity's place in the broad ecology, of the need for a diversity of economies, societies and cultures, of the need for greater economic equality and equity across the globe.
The relationship between globalisation, science and technology, democratic governance and citizens is explored using the case of genetic engineering technologies. The thesis draws on a conceptual framework provided by the theory of political economy to facilitate the assessment of the impact of a technology on society. It provides a critical framework for looking at individualised, sectoral and short term interests versus the often conflicting interests of what is termed the 'common good'. The juxtaposition of the neo-liberal, conservative and contemporarily dominant world view with that of the more radical, political economy stance exposes the tension between these two ways of viewing human history and the future of humankind.
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Weston, Delys Eleanor. "Democracy and political economy of genetic engineering." Weston, Delys Eleanor (2007) Democracy and political economy of genetic engineering. Masters by Research thesis, Murdoch University, 2007. http://researchrepository.murdoch.edu.au/397/.
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This thesis aims to provide a more critical framework for the assessment of future technologies and therefore social directions and to help to bring an understanding to the relationship between global political economy, corporate power, ideology, science and technology. This is essential given the many issues facing contemporary society - issues of sustainability and humanity's place in the broad ecology, of the need for a diversity of economies, societies and cultures, of the need for greater economic equality and equity across the globe.
The relationship between globalisation, science and technology, democratic governance and citizens is explored using the case of genetic engineering technologies. The thesis draws on a conceptual framework provided by the theory of political economy to facilitate the assessment of the impact of a technology on society. It provides a critical framework for looking at individualised, sectoral and short term interests versus the often conflicting interests of what is termed the 'common good'. The juxtaposition of the neo-liberal, conservative and contemporarily dominant world view with that of the more radical, political economy stance exposes the tension between these two ways of viewing human history and the future of humankind.
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Kalakkad, Jayaraman Suganth Kumar. "Computation of economic rebound effect in different sectors of the U.S. economy." Thesis, Massachusetts Institute of Technology, 2008. http://hdl.handle.net/1721.1/46068.
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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2008.Includes bibliographical references.
Economic rebound effect is the phenomenon in which price reduction in products and services, induced by energy efficiency increase will cause more consumption leading to an "eat away" of the potential decreases in energy usage. Several researchers have expressed their views on the existence of the effect and the related consequences of such an effect in the micro economic scale. It is recognized that the microeconomic rebound effect will depend on how the price of a good will vary when an efficiency increase is brought about and also on how the quantity consumed may vary when the price changes by a certain amount. A mathematical formulation for this effect is then developed and the two parameters required are found separately for two relevant sectors of the economy. In the first case, the rebound effect is evaluated for the US Aluminum production sector taking into consideration both primary and secondary production. Several models for determining the price elasticity of demand are developed and the share of energy cost in total costs is also found in order to estimate the rebound. The values indicate very low rebound effect in the aluminum industry. A similar trial is conducted for system wide U.S air travel and the rebound estimates are arrived at. Low to moderate take back is observed in this case due to the increased price elasticity unlike the aluminum case where a very low price elasticity of demand pulled down rebound values. In the final sections of the report, discussions including the future trends in rebound effect in the wake of the higher fuel prices and low cost product introduction etc are made. A qualitative description of the macroeconomic rebound effect is also made and conclusions regarding the presence and significance of this effect are drawn. In summarizing it is inferred that even if the rebound effect is statistically significant, it cannot be big enough to completely mask the gains in efficiency improvement. Hence efficiency improvement is inferred as a definite method to decrease energy usage despite the fact that it has its own effectiveness limit set by the rebound.
by Suganth Kumar Kalakkad Jayaraman.
S.M.
7
Chong, Barrie Fong. "Improving the cellular economy of streptococcus zooepidemicus through metabolic engineering /." St. Lucia, Qld, 2002. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe16476.pdf.
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Carver, Jason W. "Architecture of a prediction economy." Thesis, Massachusetts Institute of Technology, 2008. http://hdl.handle.net/1721.1/45807.
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Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2008.Includes bibliographical references.
A design and implementation of a Prediction Economy is presented and compared to alternative designs. A Prediction Economy is composed of prediction markets, market managers, information brokers and automated trading agents. Two important goals of a Prediction Economy are to improve liquidity and information dispersal. Market managers automatically open and close appropriate markets, quickly giving traders access to the latest claims. Information brokers deliver parsed data to the trading agents. The agents execute trades on markets that might not otherwise have much trading action. Some preliminary results from a running Prediction Economy are presented, with binary markets based on football plays during a college football game. The most accurate agent chose to enter 8 of 32 markets, and was able to predict 7 of the 8 football play attempts correctly. Source code for the newly implemented tools is available, as are references to the existing open source tools used.
by Jason W. Carver.
M.Eng.
9
Hunt, William H. "Enhancing the value of value engineering." Thesis, Georgia Institute of Technology, 2003. http://hdl.handle.net/1853/24079.
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Chammas, Nicolas Elie. "Construction industry and its role in Lebanese economy." Thesis, Massachusetts Institute of Technology, 1986. http://hdl.handle.net/1721.1/40347.
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Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Civil Engineering, 1987.MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING.
Bibliography: leaves 225-234.
by Nicolas Elie Chammas.
M.S.
11
Sikorska, Małgorzata, and P. G. Pererva. "A study of economic problems of engineering enterprises." Thesis, Кременчуцький національний університет ім. Михайла Остроградського, 2017. http://repository.kpi.kharkov.ua/handle/KhPI-Press/31074.
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Geesink, Ingrid. "Risk regulation of tissue engineering in the EU : a political economy of medicine." Thesis, Cardiff University, 2006. http://orca.cf.ac.uk/56093/.
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Tissue engineering is an emerging biomedical innovation surrounded by potentiality and risk. Based on documentary analysis and expert interviews, this study discusses different constructions of risk according to main constituencies (scientists, clinicians and manufacturers), the way they prioritise and balance these risks, and how issues are framed as problematic or not. Complexity and uncertainty are the main drivers in this exercise, interpreted in terms of boundary drawing around contested risk domains. This is followed by a discussion of the translation of risk into regulatory policy, by focusing on two recent legislative initiatives by the European Commission: one to control the quality and safety aspects of human tissues and cells (DG SANCO Directive) and the other to facilitate the marketing of tissue engineered products in the EU (DG Enterprise Regulation). These two legislative initiatives aim to overcome the current regulatory lag in Europe, where tissue engineered applications are either unregulated or subject to a broad variety in national controls. This situation is problematic for manufacturers wanting to market their products in Europe, for regulators in evaluating the risks of these technologies and defining an appropriate approval route, and for patients in terms of unequal access to potentially beneficial therapies across the continent. Firmly rooted in ambitions to make the EU a techno-scientific and bio-economic powerhouse, regulation of this domain is troubled by competing agendas of promoting trade versus protecting public health. Social and ethical considerations about the impact of tissue engineering technology allow a reconsideration of the bio-society as alternative model, taking into account the technological as well as social character of innovation.
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Sikosana, M. "A technological, economic and social exploration of phosphate recovery from centralised sewage treatment in a transitioning economy context." Master's thesis, University of Cape Town, 2015. http://hdl.handle.net/11427/13750.
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Phosphate is an important, non-substitutable nutrient for all life forms and is essential in ensuring universal food security. In the past, waste water treatment works (WWTW) typically installed effluent polishing technologies to eliminate phosphate and lower concentrations of both nitrogen and phosphate to below regulatory levels. More recently, there has been a global shift towards treating waste water as a "water-carried waste", presenting opportunities for both nutrient and energy recovery. South Africa is yet to embrace this shift, as it battles to provide universal access to basic sanitation needs and is faced with massive infrastructure maintenance and upgrading backlogs in the sanitation sector. Mature phosphate recovery technologies that produce high quality struvite for use in food production do exist. However, there is little evidence to indicate that similar phosphate recovery techniques would be economically viable or socially accepted in South Africa. Therefore, this dissertation sets out to investigate the viability of a simpler and cheaper phosphate recovery technology. The dissertation addresses the hypothesis that the South African market is better suited for low quality struvite for use in secondary (non-food) markets and that this would be cheaper than both traditional chemical precipiation (phosphate elimination) methods and high quality struvite production. This dissertation attempts to answer two key questions derived from this hypothesis by means of two separate methodologies. A qualitative methodology explores socio-technical issues to understand the potential of sewage-recovered struvite in the South African markets. This sets out to explore: What space there is for fertilizer production (such as struvite) from human waste in the South African markets? The second research component uses standard engineering economic methods, to investigate the potential for centralized recovery of nutrients through the conceptual design and a techno-economic pre-feasibility assessment of two phosphate recovery options at the largest WWIW in the Western Cape. These options are contrasted with a more traditional chemical precipitation process.
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Rawlinson, Micheal Barry. "Subcontracting relationships between small engineering firms and large motor vehicle firms in the Coventry area." Thesis, Coventry University, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.254270.
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Bjelkemyr, Marcus. "System of Systems Characteristics in Production System Engineering." Doctoral thesis, Stockholm : Skolan för industriell teknik och management, Kungliga Tekniska högskolan, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-10617.
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Torres, Arevalo Arturo Alejandro, and Changhao Han. "Air conditioning system modeling for car fuel economy simulation." Thesis, KTH, Energiteknik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-246125.
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The automotive air conditioning system is the greatest auxiliary load of a vehicle, having a considerable impact on its fuel consumption and CO2 emissions. For this reason, forecasting the influence that this sys-tem has on the fuel economy of a car is desired. The present work is dedicated to model the air conditioning system of a plug-in hybrid ve-hicle in order to predict its energy consumption. GT-SUITE was chosen as the simulation tool, where the air condi-tioner, which is a vapor-compression refrigeration system, was mod-eled by specifying its components: compressor, evaporator, thermal expansion valve and condenser. Moreover, additional sub-systems which influence the energy consumption were also considered, these are the vehicle’s cabin and the battery cooling loop. The simulated model shows good agreement with test data for impor-tant parameters such as the compressor power consumption and the air temperature after the evaporator. The percent difference between the test data and the simulation for the auxiliary power consumption (energy consumed by the A/C compressor and the charging load of the low voltage battery) is 6.25%.På ett fordon utgör luftkonditioneringssystem den främsta extraordi-nära energibelastningen, vilket har stor påverkan på bränsleförbruk-ning och koldioxidutsläpp. Av detta skäl är det önskvärt att förutse det inflytande som detta system har på fordonets bränsleekonomi. Detta arbete är har för avsikt att simulera luftkonditioneringssystemet för ett plug-in hybridfordon för att förutsäga energiförbrukningen. GT-SUITE valdes som simuleringsverktyg, där klimatanläggningen, som är ett ångkomprimerat kylsystem, modellerades genom att speci-ficera komponenterna: kompressor, förångare, värmeutvidgningsven-til och kondensor. Dessutom beaktades ytterligare delsystem som på-verkar energiåtgången, nämligen fordonets hytt och batterikylnings-loop. Den simulerade modellen visar en god korrelation med testdata för be-tydelsefulla parametrar såsom kompressorns energiförbrukning och lufttemperaturen efter förångarsteget. Den procentuella skillnaden mel-lan testdata och simuleringen för den extra energiförbrukningen (ener-gi som förbrukas av A/C-kompressorn och laddningen av lågspän-ningsbatteriet) är 6,25%.
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Michlberger, Alexander. "Development of Test Methodology for Evaluation of Fuel Economy in Motorcycle Engines." Cleveland State University / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=csu1397567798.
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McCoy, Colleen (Colleen M. ). "Fuel economy of a turbocharged, single-cylinder, four-stroke engine." Thesis, Massachusetts Institute of Technology, 2017. http://hdl.handle.net/1721.1/112556.
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Thesis: S.B., Massachusetts Institute of Technology, Department of Mechanical Engineering, 2017.Cataloged from PDF version of thesis.
Includes bibliographical references (pages 56-57).
Agriculture is the main source of livelihood for a majority of India's population. However, despite the number of workers, the yield and the yield of principal crops in India is much lower than that in developed nations. One of the reasons for this is the lack of farming mechanization in India. One of the common ways to run farming equipment is by using a single-cylinder, four-stroke diesel engine. Diesel engines can be turbocharged in order to make them more efficient for less cost. A method has been found to turbocharge a single-cylinder diesel engine by adding an air capacitor to form a buffer between the intake and exhaust strokes. This thesis analyzes how the size and heat transfer of the air capacitor for this turbocharged diesel engine are correlated to engine performance and fuel economy. According to the modeled engine, a 3.0 liter capacitor had better peak power and fuel economy at high loads and speeds than a 2.4 or 1.25 liter capacitor. Additionally, forced convection cooling on the capacitor using a fan allowed the intake air density to increase, and the engine to have better fuel economy than the . However the peak power and fuel economy of the modeled naturally aspirated engine was better than the turbocharged engine for speeds below 2500 rpm. The general trends from the model were reflected in the experimental data. The forced convection increased cooling, and improved the intake air density. However, it was difficult to make any confident recommendations about the fuel economy based on the experimental data.
by Colleen McCoy.
S.B.
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Waldspurger, Carl A. "A distributed computational economy for utilizing idle resources." Thesis, Massachusetts Institute of Technology, 1989. http://hdl.handle.net/1721.1/14506.
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Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1989.Includes bibliographical references (leaves 89-93).
by Carl A. Waldspurger.
M.S.
20
Packiriswamy, Premkumar. "Improving Power Grid Economy Using Windpower Generation." Youngstown State University / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=ysu1312907157.
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Reese, John L. "Investigation of Simple Shear Connection Economy." Ohio University / OhioLINK, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1219262914.
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Adcock, Christiane. "Evaluating Trends in Light-Duty Vehicle Technologies to Project Fuel Economy." Thesis, Massachusetts Institute of Technology, 2018. http://hdl.handle.net/1721.1/117803.
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Thesis: S.B., Massachusetts Institute of Technology, Department of Mechanical Engineering, 2018.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Cataloged from student-submitted PDF version of thesis.
Includes bibliographical references (pages 39-40).
Predicting the fuel economy of future light-duty vehicles provides insight into the expected greenhouse gas emissions, oil consumption, and operating costs in the transportation sector. Fuel economy is difficult to directly predict, however, due to the large number of vehicle characteristics that influence fuel economy. These characteristics include curb weight, powertrain efficiency, tire properties, and aerodynamic properties. In addition, the characteristics vary by powertrain technology and vehicle class. This study evaluates past trends and literature projections for each attribute. It then projects fuel economy for three powertrain technologies and eight vehicle classes using current values, past trends, and literature projections for the vehicle characteristics and the Environmental Protection Agency's drive cycles. Fuel economy for internal combustion engine vehicles (ICEVs), hybrid electric vehicles (HEVs), and battery electric vehicles (BEVs) are projected to increase at rates similar to past years. At these rates, average HEVs and BEVs will significantly exceed Corporate Average Fuel Economy standards for 2021 and 2025, and ICEVs will fall significantly short of these standards. This analysis provides an easily adaptable framework to project fuel economy that accounts for the large number of contributing vehicle characteristics.
by Christiane Adcock.
S.B.
23
Au, Samuel Kwok-Wai. "Powered ankle-foot prosthesis for the improvement of amputee walking economy." Thesis, Massachusetts Institute of Technology, 2007. http://hdl.handle.net/1721.1/40949.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2007.Includes bibliographical references (p. 103-108).
The human ankle provides a significant amount of net positive work during the stance period of walking, especially at moderate to fast walking speeds. On the contrary, conventional ankle-foot prostheses are completely passive during stance, and consequently, cannot provide net positive work. Clinical studies indicate that transtibial amputees using conventional prostheses exhibit higher gait metabolic rates as compared to intact individuals. Researchers believe the main cause for the observed increase in metabolism is due to the inability of conventional prostheses to provide net positive work at terminal stance in walking. This objective of this thesis is to evaluate the hypothesis that a powered ankle-foot prosthesis, capable of providing active mechanical power at terminal stance, can improve amputee metabolic walking economy compared to a conventional passive-elastic prosthesis. To test the hypothesis, a powered prosthesis is designed and built that comprises a unidirectional spring, configured in parallel with a force-controllable actuator with series elasticity. The prosthesis is controlled to mimic human ankle walking behavior, in particular, the power generation characteristics observed in normal human walking. The rate of oxygen consumption is measured as a determinant of metabolic rate on three unilateral transtibial amputees walking at self-selected speeds. The initial clinical evaluation shows that the powered prosthesis improves amputee metabolic economy from 7% to 20% compared to the conventional passive-elastic prostheses (Flex-Foot Ceterus and Freedom Innovations Sierra), even though the powered system is twofold heavier than the conventional devices. These results support the proposed hypothesis and also suggest a promising direction for further advancement of ankle-foot prosthesis.
by Samuel Kwok-Wai Au.
Ph.D.
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Thakkar, Sneha 1979. "Energy economy gait analysis of an autoadaptive prosthetic knee." Thesis, Massachusetts Institute of Technology, 2002. http://hdl.handle.net/1721.1/87872.
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Thesis (M.Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2002.Includes bibliographical references (leaves [52]-54).
by Sneha Thakkar.
M.Eng.
25
Berns, Madalyn S. (Madalyn Sarah). "Enhancing human metabolic economy in stair climbing via an elastic crutch mechanism." Thesis, Massachusetts Institute of Technology, 2011. http://hdl.handle.net/1721.1/68936.
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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2011.Cataloged from PDF version of thesis.
Includes bibliographical references (p. 77-79).
Crutching provides a significant increase in mobility for those with limited walking ability. While level ground walking with crutches has been studied in many different forms, stair climbing is a more energetically taxing activity and the upper arm and shoulder strength required is not always available in weaker or severely injured patients. We posit that the introduction of parallel springs spanning the elbow joint will improve the crutching experience by helping patients attain a metabolic reduction compared to unassisted locomotion. Here, we present a foundation for achieving metabolic reduction with joint-spanning elastic elements. Our approach includes three parts. First, we present an augmented crutch design with an elbow spring that can be modified with different stiffnesses. Second, we put forth a clinical testing protocol in which we measure metabolic economy via the pulmonary gas exchange technique (Vo2avg). Simultaneously recording electromyographic (EMG) signals from the primary active muscles provides a neuromuscular interpretation of the crutching activity not captured by the black-box metabolic techniques. We complete the picture by modeling the energetics of the effective elbow muscle by incorporating empirical measurements of maximum angular velocity achieved under a range of isotonic conditions. The metabolic data exhibits trends consistent with our hypothesis of metabolic reduction; although, more subjects are needed to confirm these results. All subjects reported a feeling of augmentation at the optimal stiffness condition. An analysis of the EMG results show a clear transition in muscle usage patterns from a triceps only power stroke to a combined usage of both triceps and biceps. Where the triceps are maximally active during the non-augmented state, as stiffness increases the biceps become more active and the total activation level drops, suggesting the this shift is at least partially responsible for the observed metabolic reduction. While the model correctly predicts the relative shape of the observed curve, the optimal stiffness predictions are higher than their empirical equivalents. This is most likely due to the extra help the triceps muscles received from active stabilization and power muscles not considered in the model. With a more complete muscular picture one could begin to construct an accurate method of prediction and tuning of optimal stiffness.
by Madalyn S. Berns.
S.M.
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Türk, Ferhat, and Roman Zandi. "Circular Economy : Reuse of packaging." Thesis, KTH, Hållbar produktionsutveckling (ML), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-263323.
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This study is about finding methods for reusing of packaging from Elekta's product "Leksell Gamma Knife ICON" with Circular Economy as the focus. There is no process for this today. The important thing is the analysis of the entire supply chain from Suppliers to customer and then back to Suppliers to get general ideas about what the problems are and then to draw conclusions for the opportunities that exists. The methods used are analyzes if it is cost-effective and environmentally efficient to transport back packaging to the Suppliers who handle these packaging. Costs for the return process have been calculated, which is Supplier work, packaging costs, packaging costs and transport costs. Transport emission in the form of carbon dioxide equivalents have been calculated in the return process. Carbon dioxide equivalents have been calculated for the manufacturing of new packaging and transport by road and ship. The calculated values in the return process are compared with how Elekta is doing today during the process of packing LGK as well as delivering to customers to identify if it is effective to implement a new return process. A solution proposal that fulfils the requirements from an environmental and economic perspective is reported. Environmentally, it is reduced by 459 CO2eq number of carbon dioxide equivalents with transport from the US, 457 CO2eq from China and 1185 CO2eq from Europe. Financially, the company saves 17 190 SEK with transport from the USA, 19327 SEK from China and 18 126 SEK from Europe.Denna studie handlar att om att hitta metoder för återanvändning av emballagen från Elektasprodukt ”Leksell Gamma Knife ICON” med Cirkulär ekonomi som fokus. Det finns ingen process för detta i dagsläget. Den viktiga är analysen av hela försörjningskedjan från leverantör till kund och sedan tillbaka till leverantörer för att få generella uppfattningar om vad problemen befinner sig och där ifrån dra slutsatser för möjligheterna som finns. De metoder som används är analyser om det är kostnads- och miljöeffektivt att transportera tillbaka emballage till de leverantörer som hanterar dessa emballage. Kostnader för returprocessen har beräknats vilket är leverantörsarbete, emballagekostnader, arbetskostnader och transportkostnader. Transportutsläpp i form av koldioxidekvivalenter har beräknats i returprocessen. Koldioxidekvivalenter har beräknats för tillverkning av nya emballage samt transport med lastbil och fartyg. De beräknade värden i returprocessen jämförs med hur Elekta gör idag under processen att packa LGK samt leverera till kund för att identifiera om det är effektivt att implementera en ny returprocess. Ett lösningsförslag där kraven uppfylls ur ett miljömässigt och ekonomisk perspektiv redovisas. Miljömässigt minskas det med 459 CO2eq antal koldioxidekvivalenter med transport från USA, 457 CO2eq från Kina och 1185 CO2eq från Europa. Ekonomiskt sparar företaget på 17 190 SEK med transport från USA, 19327 SEK från Kina och 18 126 SEK från Europa.
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Rodriguez, Ramirez Arturo Manuel 1977. "Valuing new economy companies using real options theory with visualization." Thesis, Massachusetts Institute of Technology, 2001. http://hdl.handle.net/1721.1/86835.
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Thesis (M.Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2001.Numbered continuously. Each leaf number is preceded with a chapter number, e.g. 1-6, 1-7, 2-8, 2-9, etc.)
Includes bibliographical references (leaf 8-86 [i.e. leaf 86]).
by Arturo Manuel Rodriguez Ramirez.
M.Eng.
28
Habibe, Tommy O. "Simulating the interactions between economy and pollution : an exploratory model." Thesis, Massachusetts Institute of Technology, 1987. http://hdl.handle.net/1721.1/14873.
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Cebesoy, Tibet. "Cost modelling system for discontinuous surface mining equipment." Thesis, University of Nottingham, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.335790.
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MacKenzie, Donald Warren. "Fuel economy regulations and efficiency technology improvements in U.S. cars since 1975." Thesis, Massachusetts Institute of Technology, 2013. http://hdl.handle.net/1721.1/80888.
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Thesis (Ph. D. in Engineering Systems: Technology, Management, and Policy)--Massachusetts Institute of Technology, Engineering Systems Division, 2013.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Cataloged from student-submitted PDF version of thesis.
Includes bibliographical references (p. 183-186).
Light-duty vehicles account for 43% of petroleum consumption and 23% of green- house gas emissions in the United States. Corporate Average Fuel Economy (CAFE) standards are the primary policy tool addressing petroleum consumption in the U.S., and are set to tighten substantially through 2025. In this dissertation, I address several interconnected questions on the technical, policy, and market aspects of fuel consumption reduction. I begin by quantifying historic improvements in fuel eciency technologies since the 1970s. First, I develop a linear regression model of acceleration performance conditional on power, weight, powertrain, and body characteristics, showing that vehicles today accelerate 20-30% faster than vehicles with similar specifications in the 1970s. Second, I nd that growing use of alternative materials and a switch to more weight-ecient vehicle architectures since 1975 have cut the weight of today's new cars by approximately 790 kg (46%). Integrating these results with model-level specification data, I estimate that the average fuel economy of new cars could have tripled from 1975{2009, if not for changes in performance, size, and features over this period. The pace of improvements was not uniform, averaging 5% annually from 1975{1990, but only 2% annually since then. I conclude that the 2025 standards can be met through improvements in eciency technology, if we can return to 1980s rates of improvement, and growth in acceleration performance and feature content is curtailed. I next test the hypotheses that higher fuel prices and more stringent CAFE standards cause automotive rms to deploy eciency technologies more rapidly. I nd some evidence that higher fuel prices cause more rapid changes in technology, but little to no evidence that tighter CAFE standards increase rates of technology change. I conclude that standards alone, without continued high gasoline prices, may not drive technology improvements at rates needed to meet the 2025 CAFE standards. Finally, I discuss the political economy of state and federal fuel economy standards. I develop a simple model of automotive manufacturers' responses to alternative systems of fuel economy regulation, using it to demonstrate the importance of several factors determining industry support for nationwide fuel economy regulations.
by Donald Warren MacKenzie.
Ph.D.in Engineering Systems: Technology, Management, and Policy
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de, Almeida Cavaleiro de Ferreira António Maria Mendes. "Circular Economy in Cities: Framework Development & Porto (Portugal) Case Study Analysis." Thesis, KTH, Energiteknik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-244373.
Full textAbstract:
Circular Economy (CE) is a recent concept that is gaining strength worldwide due to China's implementation and the European Union (EU) contribution. It is seen as the alternative to a wasteful linear economic system, with the aim to keep products at higher value and for longer time. Together with it, there is a trend of urbanization, with already 50% of the population living in cities and with expectations of this share to rise to 70%. This work main goal is to understand the role of cities in CE implementation and its monitorization. To do so one started by understanding the key concepts and state-of-the-art behaviours and technologies associated to CE, alongside an understanding of its history. Furthermore, one shifted this definition to an urban context, understanding how a circular city should look like and how and where it could leverage circularity, by also benefiting from it. Finally, a framework for the city analysis was developed, together with a Case Study relating Porto, Portugal, analysing this city from a representative perspective, while taking conclusions from the respective results. The framework is based in CE key concepts, as transparency, modularity and flexibility. It allows the definition of relevant sectors in the city, its evaluation and the interaction between them, aiming for a holistic approach. Major conclusions were taken from this work. First, Porto was considered a city with potential to be circular. Moreover, it has the opportunity in leading, together with cities as Amsterdam, Barcelona and Glasgow, the urban transition towards CE. Second, the relevant indicators for CE are yet to be defined, with this responsibility laying between the EU and the Ellen MacArthur Foundation (EMF), and, besides evaluating circularity in different levels and sectors, shall also be realistic, concerning data that can be collected today, recommending meaningful data that shall be collected in the near future. Furthermore, a multi-criteria analysis can be later included, connecting the different indicators of each sector, and then the different sectors. Third, the developed framework is a multi-sectorial framework, based in a meso-macro level. Due to CE properties, a framework of multi-level is required. The flexibility of the framework allows the analysis of different cities, in its different sectors and behaviours. Its modularity allows the connection to similar frameworks, based on the one developed in this work, that shall reflect a macro-level (national, European and global), a meso-level (focusing on the sectors and companies) and a micro-level (product), giving the holistic analysis characteristic of CE.Cirkulär ekonomi (CE) är nytt koncept som växer sig starkt på grund av Kinas implementering och Europeiska Unionens (EU) insatser. CE anses vara alternativet till ett slösaktigt linjärt ekonomiskt system, med målet att bibehålla produkter under ett högt värde under en längre tid. Tillsammans med detta pågår en trend av urbanisering där redan 50% av befolkningen bor i städer, en siffra som förväntas växa upp till 70%. Huvudmålet med detta arbete är att erhålla en förståelse av städers roll i implementationen utav CE och dess monitorization. För att uppnå detta behövs först insikt i huvudkoncepten och state-of-the-art-beteenden och teknologin som associeras med CE, samtidigt som man studerar dess historia. Dessutom, genom att applicera definitionen på ett urbant-sammanhang, förstå hur en ”circular city” bör se ut samt hur och var det kan lyfta upp det cirkulära genom att också ta fördel från det. Slutligen, utvecklades ett ramverk (framwork) för analysen av städer, tillsammans med ett Case Study relaterat till Porto, Portugal, analyserades denna stad från ett representativt perspektiv, samtidigt som slutsatser dras från the respective resultat. Ramverket (framework) baseras på CEs nyckelkoncept, såsom transparens, modularitet och flexibilitet. Det tillåter definitionen av relevanta sektorer in staden, dess utvärdering och interaktionen mellan dessa, siktandes på ett holistiskt perspektiv. Stora slutsatser drogs utav detta projekt. Först, Porto anses vara en stad med potential att bli cirkulär. Dessutom, har den möjlighet att vara ledande, tillsammans med städer som Amsterdam, Barcelona och Glasgow, att leda den urbana övergången mot CE. För det andra, relevanta indikatorer för CE måste fortfarande definieras där ansvaret ligger hos EU och Ellen MacArthur Foundation (EMF), och utöver det även utvärdera cirkularitet på olika nivåer och sektorer, bör också vara realistiskt, berörande den information som går att samla in idag, meningsfull information bör samlas in inom en snar framtid. Dessutom, kan en multi-criteria-analys inkluderas, som förbinder olika indikatorer av varje enskild sektor, och sedan olika sektorer. För det tredje, det framtagna ramverket (framework) är ett multi-sectorial-ramverk, baserat på ett meso-macro nivå. Till följd av CEs egenskaper är ett multi-level ramverk nödvändigt. Flexibiliteten av ramverket tillåter analysen av olika städer, i dess olika sektorer och beteenden. Dess modularity tillåter förbindelsen mellan liknande ramverk, baserat på den som utvecklades i detta arbete, det ska reflektera en macro-level (nationell, Europeisk och global) en meso-level (inriktat på sektorer och företag) och ett micro-level (produkt), ger den holistiska analys-karaktären av CE.
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Hardy, AliciA Jillian Jackson 1978. "Vehicle fuel economy benefit and aftertreatment requirement of an HCCI-SI engine system." Thesis, Massachusetts Institute of Technology, 2007. http://hdl.handle.net/1721.1/42986.
Full textAbstract:
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2007.Includes bibliographical references (v. 2, p. 821-823).
This body of work dimensions the HCCI fuel economy benefits and required aftertreatment performance for compliance with emissions regulations in North America and Europe. The following parameters were identified as key factors influencing the benefit of implementing HCCI over driving cycle: * Power-to-weight ratio * Operation range of HCCI * Conditions of the driving cycle * Application of constraints that cause "un-natural" mode transitions * Application of transition penalties * Available after-treatment performance * Constraints imposed by emissions regulations This study shows that development priorities for attaining maximal fuel economy benefit during urban driving cycles differ greatly in North America and in Europe due to differences in emissions regulations. The combined effect of increasing power-to-weight ratio, increasing the operation range of HCCI, removing operational constraints on HCCI implementation, and reducing fuel penalties associated with transitions into and out of HCCI mode is shown to double the emissions-constrained fuel economy benefit of HCCI during the new European driving cycle. These factors are shown to have modest impact on fuel economy benefit of HCCI during the North American city driving cycle when compliance with the more stringent emissions regulations is required. In order to attain maximal fuel economy benefit and comply with emissions regulations in California, improving conversion efficiencies in the aftertreatment of lean engine exhaust must be a primary focus. Fuel economy benefit of HCCI during the highway driving cycles is shown to be most responsive to the amount of time the engine spends in the speed and load range of HCCI operation. Time spent in HCCI mode during these driving cycles is most heavily influenced by changes in power-to-weight ratio and upper load limit for HCCI.
by AliciA Jillian J Hardy.
Ph.D.
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D'souza, Melron, and Guhan Selvaraj. "Exploring fashionability in sharing economy communities." Thesis, Uppsala universitet, Industriell teknik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-455528.
Full textAbstract:
Sharing Economy as a concept is based on providing a space for individuals that brings them together on a platform providing access to goods/services to both parties. It has grown in popularity since the 2010s due to digitalization and social media. The reason why the sharing economy is growing is due to different stakeholders involved in this concept. For example, it can be said that companies try to boost their brand by incorporating sharing economy in their portfolio or in academics where lots of resources are used in researching this concept as sustainability is trending these days. The consumer plays a role in growing interest in this concept through active participation in this economy. Now with many people involved in sharing economy, it is certain that there are different desires and needs. These desires and needs are known as motivation. Naturally, there are different types of motivations seen in sharing economy. They are economic, critical, and recreational motivation that has been researched extensively by other authors in this domain. This thesis looks at social motivation and in more specific term ‘fashionability’. Fashionability is the motivation that consumers use to ‘be unique’, ‘stand out in a crowd’, and keep up with the trends specifically to second-hand clothes. But to be unique and to stand out, there are activities that are carried out by the consumer in a second-hand store/platform. These activities are known as practices. To understand these practices, a theoretical framework known as Social Practice Theory is used. The aim of the thesis is to understand fashionability in sharing economy and to see how fashionability affects the sharing practices in second-hand consumption. To do this, the researchers have used a qualitative research method to interview active participants of sharing economy. There were ten interviewees sampled, and a semi-structure interview guide was used to understand the interviewees. The findings were that second-hand fashion was seen through different perspectives amongst consumers. Some of them were able to express themselves to enhance their identity. The researchers also analyzed that fashionability was indeed a motivator since this was seen as a starting point towards the consumption of second-hand clothes. There were seven practices found through the results in this thesis. The researchers analyzed these seven practices and theorized the links between these practices needed to be sustained.
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Bhaumik, Vijan. "Supply chain practices in the context of an emerging economy." Thesis, Massachusetts Institute of Technology, 2010. http://hdl.handle.net/1721.1/59227.
Full textAbstract:
Thesis (S.M. in System Design and Management)--Massachusetts Institute of Technology, Engineering Systems Division, System Design and Management Program, 2010.Cataloged from PDF version of thesis.
Includes bibliographical references (p. 90-92).
The emergence of the BRIC economies of Brazil, Russia, India and China as a formidable economic powerhouse is turning into a reality. The center of the world's economic gravity is slowly shifting towards these emerging economies. As per research performed by Goldman Sacs' the BRIC economies could become the four most dominant economies by 2050. As per their study China and India would become the dominant supplier of manufactured goods and services while Brazil and Russia would dominate in supply of raw materials. The BRIC economy today makes up about 25% of the land mass and has 40% of the world's population. As multinationals scramble to tap into these growing emerging markets, they have begun to acknowledge that supply chain management is an essential ingredient of a successful business strategy. Success stories of Wal-Mart, Dell and Toyota have brought in the realization that to compete and win in the market place a winning supply chain strategy is a must. This has resulted in corporations trying to benchmark their supply chain strategies against this best in class strategies. However, this kind of comparison does not always work since there are a multitude of differences between companies, industries and countries. The existing practice of developing products and services for the developed economy and then tailoring these products for other economies around the world will not suffice anymore. Companies must now learn how to develop products for countries like India, sometimes from scratch and then tailor them for other geographies. To compete in this space of rapid economic growth firms need to analyze, design and optimize their product portfolio for emerging markets. To develop these "no frills" products for emerging economies, the supply chain designed for developed countries isn't adequate to meet the unique challenges of an emerging economy with its underdeveloped infrastructure, technology and human capital resources. To be competitive corporations should re-evaluate their supply chain strategies to customize it for emerging market conditions and in many cases build it from scratch. This thesis examines the unique characteristics of supply chain by studying successful supply chain strategies employed by Indian firms and proposes frameworks and strategies to help companies innovate in their supply chain design. This thesis develops a generic framework to design effective supply chains for emerging economies by looking at five key elements or "Five Pillars" of supply chain. The five key elements were thoroughly evaluated to understand the key challenges in each pillar and develop effective "Customized Practices" in the context of an emerging economy. The five pillars which were evaluated were Demand and Supply Planning, Sourcing and Procurement, Operations, Transportation, Warehousing and distribution. The framework takes a holistic approach by aligning business strategies with operating principles to develop the customized practices. The framework was then validated by performing a deep dive analysis of the successful supply chain case of the Tata Nano small car. Analyzing the Tata Nano supply chain through the lens of this framework provided key insights into the supply chain challenges faced by firms operating in an emerging economy and the unique customized practices used by these firms to operate efficiently. Use of this framework will bring awareness of the supply chain challenges in emerging economies and the customized practices firms use to help guide organizations in designing and operating their supply chains.
by Vijan Bhaumik.
S.M.in System Design and Management
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Reagle, Joseph M. (Joseph Michael). "Trust in a cryptographic economy and digital security deposits : protocols and policies." Thesis, Massachusetts Institute of Technology, 1996. http://hdl.handle.net/1721.1/11016.
Full textAbstract:
Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1996.Includes bibliographical references (p. 106-113).
by Joseph M. Reagle, Jr.
M.S.
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Cannon, Joseph, Vesmiene Ceasor, Fernando Escobar, Gloria Huapaya, Deepak Lavetti Eric Kumar, Stephen Lucero, Anthony Nguyen, et al. "A systems engineering analysis of energy economy options for the DDG-51 class of U.S. Naval ships." Thesis, Monterey, California. Naval Postgraduate School, 2010. http://hdl.handle.net/10945/6950.
Full textAbstract:
Approved for public release; distribution is unlimitedApproved for public release; distribution is unlimited
The SECNAV has identified an ambitious set of goals for the Navy's energy programs. The authors addressed DoN energy surety, economy, and ecology goals, scoped the problem to focus on the economy aspect of the DoN's energy goal, and further bounded the analysis to energy economy of the DDG-51 class of surface combatants which appeared to be an area with potentially high return on investment. The team determined that if energy was conserved or better utilized then the triad of SECNAV goals for energy surety, economy and ecology was positively addressed. This report documents a method to assess energy consumption that could be used to make trade-offs for current and future ships. Eight subsystems, along with fuel type, were researched for alternative solutions, with eight of nine subsystem alternatives resulting as "more cost effective." By implementing the optimal recommendations from our team findings and using the fully burdened cost of fuel, we estimate that the DDG-51 program could save $1 .9M per year per ship. For a fleet of 50 ships, this translates to a savings of $9 50M over ten years.
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Kong, Caleb J. "Engineering High Reaction Economy or, An Intensification/Scoring Program for the Preparation of Simple and Complex Molecules." VCU Scholars Compass, 2019. https://scholarscompass.vcu.edu/etd/6023.
Full textAbstract:
Success of newly discovered chemistry in academia is often scored in terms of its novelty and level of scholarship. In industrial settings, cost, safety and quality are often times the ruler by which new processes are measured. Our group has identified that there is a gap between these two measures of success and has sought to develop principles in order formalize an approach to synthetic strategy and developing ready-to-implement manufacturing processes for molecules, simple and complex.
Some of these principles include (1) the development and application of new chemical methods and reactor technologies (2) recognition of globally amenable chemical environments for each chemical step to consolidate unit operations and obviate the need for purification (3) vertical integration of starting materials to generate complexity from the most elementary building blocks in a chemical supply space and (4) the development of new materials that allow for recovery and reuse. These principles are iteratively scored and redeveloped through various metrics that our group has identified as effective tools in maximizing efficiency such as cost of goods (CoG), process mass intensity (PMI) and volume-time output (VTO). The intended benefits of this approach is that these processes become not only cost effective but sustainable and impactful in the manufacturing landscape and increase access of these products to consumers.
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Zhu, Jianfeng M. Eng Massachusetts Institute of Technology. "An evaluation of the hydrogen economy and metal oxide based photo-electrochemical cells." Thesis, Massachusetts Institute of Technology, 2010. http://hdl.handle.net/1721.1/62684.
Full textAbstract:
Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 2010.Cataloged from PDF version of thesis.
Includes bibliographical references (p. 130-142).
Fossil fuels depletion and climate change are driving the need for sustainable development and renewable energy sources globally [1]. Solar being the most abundant and widespread source of renewable energy is resulting in a rapidly growing, with a growth rate more than 35% annually for the past 10 years [4]. Hydrogen is an ideal energy carrier for next generation given its high efficiency, environmental friendliness, wide application as well as several attractive methods for storage and distribution [17]. The hydrogen economy, a proposed system of producing, delivering and employing energy by using hydrogen, is under intensive research and development, and is projected to be realized at the end of this century as one of the leading suppliers [60]. Photo-electrochemical (PEC) cells connect the solar energy and hydrogen economy together by directly converting solar energy into chemical energy in the form of hydrogen gas. The metal oxide based PEC cell has advantages of low cost, high stability and durability and environmental friendliness [14], a good option for commercialization. With the rapid development of nanotechnology in recent years, novel nano-structured metal oxide PEC cells can have higher efficiency and better performance due to the effects of quantization, large surface areas, improved charge transport, etc. In this thesis, the current status and future development of the hydrogen economy in terms of identifying the markets, opportunities and risks of solar-hydrogen has been reviewed and accessed. The technology review of PEC cells in terms of the working mechanism and efficiency determining factors has been studied. The current research efforts on metal oxide based PEC cells for optimizing the performances and processing methods have also been studied. A case study and cost modeling in the context of scenario has been conducted; the analysis showed the cost of PEC cells was still very high mainly due to the high materials and processing costs. Thus, future research development should focus on the technological approaches with low materials and processing costs and high energy conversion efficiency for earlier commercialization of PEC cells. Besides, hydrogen storage, distribution, safety codes and standards, education and training as well as fuel cell technology must also require intensive research and development to insure the realization of solar-hydrogen economy.
by Jianfeng Zhu.
M.Eng.
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Nitschke, Ronald Garrett. "The effects of spark-ignition engine design parameters on performance and economy : a modelling study." Thesis, Massachusetts Institute of Technology, 1987. http://hdl.handle.net/1721.1/14807.
Full text
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Hartman, Joseph C. "Evaluating multiple options in parallel replacement under demand and rationing constraints." Diss., Georgia Institute of Technology, 1996. http://hdl.handle.net/1853/24881.
Full text
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German, Luis David. "Low volume manufacturing strategies for the automotive industry : a global and emerging economy perspective." Thesis, Massachusetts Institute of Technology, 1998. http://hdl.handle.net/1721.1/9582.
Full textAbstract:
Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 1998.Includes bibliographical references (p. 117-119).
Low volume manufacturing has become increasingly important for the automotive industry. Globalization trends have led automakers and their suppliers to operate in developing regions of the world were economies of scale can not always be achieved. Niche markets for the performance/sport cars and some luxury sedans have been gaining economic importance, further fueling the need for developing more economic efficient low volume manufacturing operations. While low volume manufacturing has been the subject of much research, this has largely focused on flow optimization, inventory reduction and logistics improvements. Less attention has been paid to the subject of process technology choices. Identifying and employing optimal processing technology for low volume applications can reduce costs significantly. This thesis presents technical cost modeling as an effective methodology for examining low volume manufacturing cases and identifies typical areas of concern for low volume producers. General strategies for reducing the cost penalties associated with low volume production are also presented. Four cases are analyzed; Argentine engine valve manufacturing, Thai steering wheel manufacturing, automobile radiator manufacturing, and sheet metal stamping. These cases exemplify three of the most common issues affecting low volume manufacturing; the selection of optimal alternative manufacturing technologies, tooling related issues such as the optimal investment levels and the choice of tooling technologies, and the choice of automation levels. Results show that alternative process technologies may address low volume problems associated with long set-up times, poor equipment and tooling utilization and high tooling investment. The use of alternative tools which are less expensive, but have a shorter life are also potential solutions. Automation level optimization can be used to target the required output levels as well as affect the labor capital balance.
by Luis David German.
Ph.D.
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MacKenzie, Donald Warren. "Trends and drivers of the performance : fuel economy tradeoff in new automobiles." Thesis, Massachusetts Institute of Technology, 2009. http://hdl.handle.net/1721.1/52758.
Full textAbstract:
Thesis (S.M. in Technology and Policy)--Massachusetts Institute of Technology, Engineering Systems Division, Technology and Policy Program, 2009.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Includes bibliographical references (p. 107-111).
Cars sold in the United States have steadily become more fuel-efficient since the 1970s, and assessments of emerging technologies demonstrate a significant potential for continued evolutionary improvements. However, historic efficiency improvements have not always translated into reduced rates of fuel consumption. Instead, most of the technological progress of the past 20 years has been dedicated to offsetting increased acceleration performance, while fuel consumption has languished. This work addresses the questions of (1) why new technology is dedicated to performance rather than fuel consumption, and (2) what policy structures and stringencies can most effectively encourage new technology to be dedicated to reducing fuel consumption. A technology allocation model was developed which couples projections of fuel consumption and performance tradeoffs to consumers' willingness to pay for these attributes, in order to maximize the combined value of these attributes to consumers. The model was calibrated using stated willingness to pay, car price data, and historic trends in performance and fuel consumption. The model was used to investigate the effects of various policies on the balance between performance and fuel consumption. Particular attention was paid to the Emphasis on Reducing Fuel Consumption (ERFC), which quantifies the amount of technology dedicated to improving fuel consumption rather than other attributes. Under baseline conditions of constant gasoline price and no policy intervention, the majority of new technology continues to flow to increasing performance. The performance-fuel consumption balance is sensitive to policy signals. Fuel taxes, incentives (e.g. feebates), and fuel economy standards are all shown to be effective for increasing ERFC, although they have different implications for consumers' costs and automakers' profitability. Policies that merely increase the rate of technology deployment are found to be less effective for increasing emphasis on reducing fuel consumption.
by Donald Warren MacKenzie.
S.M.in Technology and Policy
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Bastien, Étienne Joseph Marcel. "Towards Circular Economy : Wood ash management for biomass CHP plants in the UK." Thesis, KTH, Kraft- och värmeteknologi, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-284568.
Full textAbstract:
In response to climate change, the United Kingdom has committed to reach net zero greenhouse gas emissions by 2050. To reach the set target, the Committee on Climate Change is planning a notable increase of bioenergy up to 15% in the national energy mix and thus an increase of the amount of ash produced. Nowadays, ash is rarely recycled or reused but mostly landfilled, which is both costly for the industry and unsustainable. In parallel, agricultural land and forestry suffer both from soil acidification and nutrient depravation due to the intensive land utilization practices. This study reviews the potential of a circular economy of wood ash for application on land and forestry through a case study based on the ash generated by two biomass-fired CHP plants in the UK. It summarizes the general ash characteristics, the factors influencing its quality, and the optimal composition sought for application to land and forestry. The study also aims at defining the main concerns with regards to potential contamination of the environment and dangers to human health. Eventually, the process to evaluate and establish recycling of the ash for both plants was analysed in light of the above. The study found that ash is a remarkably variable co-product, depending mainly on the fuel input and combustion conditions. Ash is a good replacement for agricultural lime and conserves a notable part of the biomass fuel nutrients. It was estimated that ash could cover a significant part of the liming and fertilising demand in the UK by 2050, and deliver a substantial financial value to a power plant. However, contamination concerns are present, especially heavy metals, which could lead to damage on the environment and reduction of the growth rate. The study found that ash recycling in the UK is currently a challenging process, that should not be overlooked when designing a biomass project. When they exist, procedures are demanding with regards to testing, which can financially deter power plants to engage in ash recycling processes.Som ett svar på klimatförändringarna har Storbrittanien åtagit sig målet att nå nollutsläpp av växthusgaser till år 2050. För att nå det uppsatta målet planerar utskottet en anmärkningsvärd ökning av bioenergi upp till 15% i den nationella energimixen och därmed en ökning av mängden producerad aska. Numera återvinns eller återanvänds aska sällan men deponeras mest, vilket är både kostsamt för industrin och ohållbart. Parallellt lider jordbruksmark och skogsmark både av markförsurning och näringsämnesförlust på grund av det mycket intensiva lantbruket. Denna studie granskar potentialen för en cirkulär ekonomi av träaska för applicering på jordbruks- samt skogsbruksmark genom en fallstudie baserad på askan som genereras av två vedfliseldade kraftvärmeverk i Storbritannien. Den sammanfattar de allmänna askegenskaperna, de faktorer som påverkar dess kvalitet och den optimala sammansättningen som eftersträvas för applicering på mark och skog. Studien syftar också till att definiera de viktigaste problemen med avseende på potentiell miljöförorening och faror för människors hälsa. Slutligen analyseras processen för att utvärdera och etablera återvinning av askan för båda kraftverken med tanke på de ovanstående utmaningarna. Studien visade att aska är en anmärkningsvärt variabel biprodukt, beroende främst på bränsletypen och förbränningsförhållandena. Askan är en bra ersättning för jordbrukskalk och innehåller en anmärkningsvärd del av de ursprungliga biomassans näringsämnen. Uppskattningsvis skulle askan kunna täcka en betydande del av efterfrågan på kalkning och gödning i Storbritannien till år 2050 och samtidigt leverera ett betydande ekonomiskt värde till kraftverken. Det finns emellertid kontamineringsproblem, särskilt p.g.a. tungmetaller, som kan leda till skador på miljön och minskning av tillväxttakten. Studien bevisar att askåtervinning i Storbritannien för närvarande är en utmanande process, som inte bör förbises när man utformar ett biobränsleprojekt. När de existerar är procedurerna mycket krävande när det gäller testning, vilket kan avskräcka kraftverken ekonomiskt för att delta i askåtervinningsprocesser.
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Wadstein, Victor. "Circular Economy in Plastic Production : The recycling challenges and solutions in plastic production." Thesis, KTH, Skolan för industriell teknik och management (ITM), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-264551.
Full textAbstract:
The consequences of the linear economy of plastic production has started to show. Media reports of "plastic seas," beaches full of waste, and habitats and environments destroyed. The question on how to make plastic production more circular have been a hot topic. Every year 311 million tonnes of plastic gets produced around the world. The plastics that can be recycled are thermoplastics. 70% of all produced plastic is made from five different plastic materials, PVC, PET, EPS, PP, and HDPE. Of the total of 311 million tonnes 87 million tonnes of that plastic is plastic packages for household consumers. Of that 87 million tonnes 32% of that is never collected, ending up in the oceans. Sweden is doing well compared to most countries, 99% of all plastic in Sweden is collected. The number is much thanks to all the regulations, recycling organs, and producer requirements that are active in Sweden compared to many other countries. This report is going to point out some important challenges and its solutions to move towards a globally circular economy. Sweden still faces challenges. Of all plastic collected only 50% goes into recycling while the other 50% ends up for incineration to energy recovery, to warm up houses and give electricity to cities. There are four different methods of recycling in facilities today. Closed - loop Open - loop Chemical recycling Energy recovery through incineration Closed - loop recycling is when the recycled product ends up as the same product after the recycling process while open - loop is when something gets recycled to a plastic product with a lower value than the original product. Chemical recycling is when chemicals in the plastic are extracted and recycle these, usually for fuels. Energy recovery through incineration is when plastic waste is burnt down to recover the energy stored in the plastic. The most common recycling methods in Sweden are open-loop recycling and energy recovery through incineration. One plastic container differs from the rest. The PET - bottles. Of all plastic bottles 85% are collected and recycled in Sweden much thanks to the deposit-refund system available in Sweden. Plastic bottles often follow a process called URRC process, which is a full process from collecting plastic bottles to selling clean plastic flakes that can be renewed to new plastic bottles. Sweden is building the largest recycling facility in Europe, with a technology called "Near-echnology" which is a technology with Near-infrared light to efficiently sort out coloured and clear plastic as well as type of material and chemical compound. This technology will help the facility sort out more than 50% plastic waste compared to other facilities in Europe, an essential step toward a circular economy. Another meaningful action is in the form of global and international producer recommendations, where strict regulation regarding production, design, and materials are agreed upon that favours packaging improving its recycling abilities. These regulations come from the recycling companies such as Returpack and Plastkretsen.Konsekvenserna från en linjär ekonomi inom plastproduktion har börjat att visas. Media rapporterar om "plast hav", stränder fulla med avfall med habitat och miljöer förstörda. Frågan hur man kan göra plastproduktionen mer cirkulär har varit ett hett debatterat ämne. Varje år produceras 311 miljoner ton plast runt om i världen. Plasten som idag går att återvinna kallas Termoplaster. Av de plasterna består 70% av dessa olika plastmaterial, PVC, PET, EPS, PP och HDPE. Av all tillverkad plast är 78% miljoner ton plastförpackningar varav 32% av det som tillverkas hamnar i haven. Sverige sköter sig bättre än många andra länder när det gäller uppsamling av plast plockas 99% upp. Denna siffra är mycket tack vare de lagar, förordningar och återvinning organ som existerar i Sverige jämfört med andra länder. Detta arbete kommer att fokusera på de utmaningar som uppkommer när man ska röra sig mot en mer cirkulär ekonomi och de lösningar som finns för att klara av utmaningarna. Sverige står för ett antal utmaningar. Av all plast som samlas in i Sverige går 50% till återvinning av materialet medan 50% går till förbränning för att få ut energi, för att värma hus och generera energi till städerna. De fyra vanligaste metoderna som används i återvinning av plast idag är. Closed - loop Open - loop Kemisk återvinning Förbränning för energi Closed - loop är en återvinningsmetod som betyder att när en produkt återvinns kommer den komma ur cykeln som samma eller liknande produkt, detta kan jämföras med open - loop där produkten återvinns till ett material med sämre kvaliteter. I kemisk återvinning återvinner man kemikalierna i plasten. Vanligt är att utvinna kemikalier för att sedan använda som olika bränslen. Den sista vanligaste metoden är förbränning av plast för att få ut energin som finns lagrad i plasten. De vanligaste metoderna i Sverige är idag open - loop samt förbränning. En typ av plastförpackning skiljer sig dock mot mängden, PET - flaskor. Av alla flaskor återvinns 85% till en ny plastprodukt. Detta är mycket beroende på det välfungerande pantsystem som finns i Sverige. Insamlade plastflaskor följer i Sverige en process som heter URRC - processen. Denna process följer allt från insamling av plastflaskor till försäljning av klara plastflingor som kan återvinnas till bland annat flaskor. Sverige bygger även Europas största återvinningscentral för plastinsamling. Med en ny teknologi som de kallar "Near- Technology" som bygger på Near - infrarött ljus´ skall öka precisionen på sortering av plasten. Från material, färg och kemisk uppsättning. Potentialen är 50% mer sorterad plast än någon annan anläggning i Europa. Andra nödvändiga åtgärder för att skapa en cirkulär ekonomi är i form av strikta förordningar, skärpa lagar och att plastproducenter följer de rekommendationer som kommer från till exempel, Returpack och Plastkretsen.
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Stichter, Jonathan Seth. "Investigation of vehicle and driver aggressivity and relation to fuel economy testing." Thesis, University of Iowa, 2012. https://ir.uiowa.edu/etd/3541.
Full textAbstract:
As vehicle technologies continue to improve it is becoming more evident one of the last major factors impacting fuel economy left today is the driver. In this study the driver is defined as the operator of a vehicle and the difference between driving styles of the driver and vehicle is defined as aggressivity. Driver aggressivity is proven to have a substantial impact on fuel economy in many studies. Many fuel economy tests have been created, all to measure the fuel efficiency of today's vehicles and their related technologies. These tests typically require that the drivers be trained or experienced in fuel economy testing unless the impact of the driver on fuel economy is the variable being tested. It is also recommended, for certain tests, that the driver stay with the same vehicle for the tests entirety. Although these are the requirements, having the same trained drivers for the entirety of a fuel economy test may not always be a viable option. This leads to the question of, what impact can a set of drivers, who are asked to drive the same, have on fuel consumption during a fuel consumption test? The SAE J1321 Type II Fuel Consumption Test Procedure was followed on two identical trucks with two drivers that were untrained in fuel economy testing in order to answer this question. It was found in this particular study that the driver variability can impose up to a 10% fuel economy difference on shorter distance routes where the driver is kept the same. By increasing the distance of the route and swapping drivers variability in fuel economy reduced to 5%. It was shown by this particular test that the impact of the driver when asked to drive the same is minimal compared to real world results of up to 30%. A larger data set and more testing is still necessary to completely understand and validate the impact of the driver on fuel economy testing.
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Cross, Stephen J. "The application of high quality maritime simulator training to improve safety and economy in shipping operations." Thesis, Southampton Solent University, 2009. http://ssudl.solent.ac.uk/1754/.
Full textAbstract:
Statistics of maritime casualties continue to be the driver of improvement of human performance or rather reduction of human error. Still, too many accidents occur and some can be traced back to the lack of proper training and the lack of certain required skills and competences of the seafarer. One possible means of performance improvement is envisaged to come from (additional) high quality training, using maritime simulator systems. If so, (additional) costs will occur. But if the amount of the increased costs of training is less than the funds to be saved by avoiding accidents, it will justify that such trainig efforts should take place. The overall objective of this thesis is thus to demonstrate how and by how much, well structured, high quality, maritime simulator training can positively influence the safety and economic efficiency of shipping operations. This requires a description of the education and training efforts, simulator applications, human error catagories, performance improvement and the costing and comparison of these various items. The main and novel research efforts will be to determine what percentage performance improvement can be achieved with high quality simulator training. This is done by observations of groups of simulator trainees during various and multiple types of exercises. When the simulator training is performed in the structured manner as described, it should lead to an improved performance and thus a reduction of the number of maritime accidents by an appreciable percentage. The overall result when implemented, could then be that shipping operations become both safer and economically more efficient. As this is usually seen as a contradiction, in which safety is regarded to cost money and economy to generate money this initiative would indeed be worthwhile.
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Galindo, Gutierrez José Carlos. "Privatization in Mexico--its role in the economy and the development of the public infrastructure." Thesis, Massachusetts Institute of Technology, 1994. http://hdl.handle.net/1721.1/35423.
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Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 1994.Includes bibliographical references (leaves 141-146).
by José Carlos Galindo Gutierrez.
M.S.
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Mustafa, Mohamed. "Development of a Framework for Circular Economy within Furniture Manufacturing Companies." Thesis, Linnéuniversitetet, Institutionen för byggd miljö och energiteknik (BET), 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-106037.
Full textAbstract:
AbstractThe fast spreading industrialization revolution around the world has resulted in a rapid cycle of production and consumption of resources. Resulting in sustainable solutions being a fundamental need and resolutions which include efficient resources use. The concept of Circular Economy includes specific practices which take into consideration reusing resources through sustainable solutions resulting in the minimization of waste as well as the use of resources more efficiently. This study shows that organization approach circular economy in different ways, resulting in various definitions. Furthermore, the study emphasizes on the importance of developing a framework for circular economy when seeking to implement the concept. This research aims to develop a framework for the implementation of circular economy in consideration to furniture manufacturing companies. Furthermore, this research focuses on four theories: circular economy, sustainable solution, resource efficiency, and product End-of-Life (product EoL). A mixed method approach consisting of a semi-structured interview and a survey were used to help reach the aim of this study. The results from the interview two furniture manufacturing companies show that the companies use different aspects of the circular economy. In conclusion, companies with goals of being more sustainable should start considering circular economy principles from an early stage. This includes having a strict rule of only approving environmentally friendly materials. This also leads to the benefit that the practices of refurbishing and reusing allows for products to live for numerous lifetimes
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Kambanis, Leonidas M. Th. "Assessing high speed waterborne (HSW) services, based on synthetic aspects of route characteristics, transport economy, and vessel performance." Thesis, Massachusetts Institute of Technology, 1995. http://hdl.handle.net/1721.1/36092.
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Plumley, Michael J. "Design and prototype of dual loop lubricant system to improve engine fuel economy, emissions, and oil drain interval." Thesis, Massachusetts Institute of Technology, 2015. http://hdl.handle.net/1721.1/97842.
Full textAbstract:
Thesis: Ph. D., Massachusetts Institute of Technology, Department of Mechanical Engineering, 2015.Cataloged from PDF version of thesis.
Includes bibliographical references (pages 181-193).
Regulations aimed at improving fuel economy and reducing harmful emissions from internal combustion engines place constraints on lubricant formulations necessary for controlling wear and reducing friction. Viscosity reduction results in fuel economy improvement, with benefits of up to three percent reported in some studies. Such reductions are limited by engine durability constraints. Recent limits on oil additives, driven by emissions aftertreatment requirements, impose additional design tradeoffs. The benefit of segregating lubrication systems, in light of modern formulation constraints, is investigated through modeling and experiment. Many findings are applicable to spark and compression ignition engines, with an emphasis placed on diesel engines, given the implementation of the first heavy duty diesel fuel economy regulations. Nearly all engines used today employ a lubrication system with a pump delivering an oil to all engine regions. Axiomatic design concepts are applied to describe the associated design tradeoffs. Two dual loop prototypes were developed, incorporating independent oil systems for the engine valve train and power cylinder, decoupling many lubricant functional requirements. Oil analysis and friction measurement were used to quantify performance. A combination of high viscosity lubricant in the valve train, with low viscosity in the power cylinder, increased fuel economy while maintaining wear protection. Effective protection of subsystems from contamination and oil degradation, particularly the elimination of soot in the valve train, was demonstrated. Detailed friction and oil composition modeling was used to investigate opportunities for further friction and wear reduction. Techniques for investigating oil composition changes along the liner in modern friction models are developed. Differences in lubricant functional requirements along the liner are highlighted. Model results indicate that vaporization along the liner increases lubricant viscosity near piston top dead center, providing a potential wear reduction benefit.
by Michael J. Plumley.
Ph. D.