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1
Sheldon, Jeffrey W. (Jeffrey William) 1978. "Strength reduction of integer division and modulo operations." Thesis, Massachusetts Institute of Technology, 2001. http://hdl.handle.net/1721.1/86849.
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Thesis (M.Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2001.Includes bibliographical references (leaves 53-54).
by Jeffrey W. Sheldon.
M.Eng.
2
Gambell, Anthony C. (Anthony Charles) 1976. "Operations improvements through non=value-added step reduction." Thesis, Massachusetts Institute of Technology, 2004. http://hdl.handle.net/1721.1/34789.
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Thesis (M.B.A.)--Massachusetts Institute of Technology, Sloan School of Management; and, (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering; in conjunction with the Leaders for Manufacturing Program at MIT, 2004.Includes bibliographical references (p. 63-64).
This thesis demonstrates how factories can use the Value Stream Mapping method to reduce both direct and indirect labor cost components through a non-value-added step reduction. The principal objective of this internship was to identify instances of non-value-added work in a product value stream and implement actions to reduce or eliminate it. Operations improvements included actions to eliminate waste through bottleneck utilization improvements, paperwork reduction, planning tool development and safety stock level calculation. From a leadership perspective, this thesis explores the challenges of cross-cultural and second-language change management.
by Anthony C. Gambell.
S.M.
M.B.A.
3
Skogetun, Erik. "Reduction of Common Operations in a Neural Network." Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-281880.
Full textAbstract:
Machine learning models are becoming increasingly complex, and particularly artificial neural networks. Meanwhile, solutions are moving closer towards the edge with implementations on devices such as smartphones, TVs and cameras. This creates a demand for efficient models that perform well despite restricted computational resources. One particularly successful convolutional neural network that was first introduced in 2014 is the Inception network, which in its first edition was named GoogLeNet. The Inception network’s structure was highly successful for complex image classification and the model has since then been developed iteratively, resulting in several new versions. The latest version, Inception-V4, was presented in 2016 and the model structure is still highly utilized, and many modern neural networks draw inspiration from it. The aim of this thesis is to develop and evaluate a more lightweight and potentially more efficient version of the Inception network, and discuss its opportunities and challenges. The proposed lighter version, named LightInception, is based on the original Inception-V4 model, where a process called reduction of common operations was implemented to lower the network’s complexity. Reduction of common operations is a method developed in this study for simplifying networks with parallel structures, such as the Inception network. The process draws inspiration from multiple modern network structures and best practices. In practice, its implementation on Inception-V4 lowered the redundancy in the network and reduced the total number of parameters by 33%. LightInception was evaluated on six diverse data sets with regard to inference time, accuracy, loss, convergence, training volatility, and weight utilization. The model showed promising results with higher or equal accuracy for at least half of the evaluated data sets. This indicates that reduction of common operations may be an efficient means to reduce model complexity without losing representative power, and the process is suggested for further investigation.Maskininlärningsmodeller blir allt mer komplexa, och särskilt artificiella neurala nätverk. Samtidigt flyttar dessa lösningar från molnet och allt närmare de enheter där de faktiskt används, så som smartphones, TV-apparater och kameror. Detta skapar ett behov av effektiva modeller som fungerar bra trots begränsade beräkningsresurser. Ett särskilt framgångsrikt faltningsnätverk ("convolutional neuralt nätverk") som introducerades 2014 är Inception, som i sin första utgåva fick namnet GoogLeNet. Inceptionstrukturen var framgångsrik för komplexa utmaningar inom bildklassificering och modellen har sedan dess utvecklats iterativt, vilket resulterat i flera nya versioner. Den senaste versionen, Inception-V4, presenterades 2016 och är fortfarande väl utnyttjad, och många moderna nätverksstrukturer hämtar inspiration från denna. Syftet med denna studie är att utveckla och utvärdera en mindre komplex och potentiellt mer effektiv version av Inception-nätverket, samt diskutera dess möjligheter och utmaningar. Den föreslagna versionen, med namnet LightInception, är baserad på den ursprungliga Inception-V4-modellen, där en process som heter reduction of common operations implementeras för att minska nätverkets komplexitet. Reduction of common operations utvecklades i denna studie som en metod för att förenkla nätverk med parallella strukturer, så som Inception-nätverket. Processen tar inspiration från flera moderna nätverk och metodiker. I praktiken ledde dess implementation till en minskning av redundansen i nätverket och det totala antalet parametrar minskade med 33 %. LightInception utvärderades på sex dataset med avseende på inferensstid, noggrannhet, loss, konvergens, träningsvolatilitet och uttnyttjandegraden av nätverkets vikter. Modellen visade lovande resultat med högre eller lika noggrannhet för åtminstone hälften av de utvärderade dataseten. Detta indikerar att reduction of common operations kan vara ett effektivt sätt att sänka modellkomplexiteten utan att förlora representativ kraft, och processen föreslås att undersökas i vidare forskning.
4
Teytelman, Anna. "Modeling reduction of pandemic influenza using pharmaceutical and non pharmaceutical interventions in a heterogeneous population." Thesis, Massachusetts Institute of Technology, 2012. http://hdl.handle.net/1721.1/72847.
Full textAbstract:
Thesis (Ph. D.)--Massachusetts Institute of Technology, Sloan School of Management, Operations Research Center, 2012.Cataloged from PDF version of thesis.
Includes bibliographical references.
In an event of a pandemic influenza outbreak such as the great "Spanish Flu" of 1918 and the more recent 2009-2010 H1N1 "Swine Flu" scare, pharmaceutical as well as non-pharmaceutical resources are limited in availability and effectiveness. In this thesis we apply OR methods to evaluate the effectiveness of such resources and the strategies for reducing the number of infections resulting from an outbreak. In the first half of this work, we focus on epidemiological analysis of influenza modeling in a heterogeneous population. The majority of existing epidemiological literature models influenza spread in a statistically homogeneous population, but the model-based inclusion of heterogeneity by contact rate, susceptibility, and infectivity introduces significant effects on disease progression. We introduce a new discrete-time influenza outbreak model for a heterogeneous population and use it to describe the changes in a population's flu-related characteristics over time. This information allows us to evaluate the effectiveness of different vaccine targeting techniques in achieving herd immunity, that is, the point at which there is no further growth in new infections. In the second half of this work we switch to a practical application of OR methods in a pandemic situation. We evaluate the effectiveness of vaccines administered to US states during the 2009-2010 H1N1 pandemic. Since the US is geographically diverse and large, the outbreak progressed at different rates and started at different times in each individual state. We discuss dynamic, multi-regional, vaccine allocation schemes for large geographical entities that take into account the different conditions of the epidemic in each region and maximize the total effect of available vaccines. In addition, we discuss effective strategies for combining vaccines with non-pharmaceutical interventions such as hand-washing and public awareness campaigns to decrease the strain of an outbreak on the population.
by Anna Teytelman.
Ph.D.
5
Xia, YuXin M. B. A. Sloan School of Management. "M28 Fixed wing transport aircraft cost reduction." Thesis, Massachusetts Institute of Technology, 2011. http://hdl.handle.net/1721.1/66038.
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Thesis (M.B.A.)--Massachusetts Institute of Technology, Sloan School of Management; and, (S.M.)--Massachusetts Institute of Technology, Engineering Systems Division; in conjunction with the Leaders for Global Operations Program at MIT, 2011.Cataloged from PDF version of thesis.
Includes bibliographical references (p. 146-148).
The M28 is a Polish short-takeoff-and-landing (STOL) light cargo aircraft developed in 1984 and currently built by PZL Mielec, a subsidiary of United Technology Corporation (UTC). There has been renewed interest in the product from military and commercial markets due to its impressive STOL capabilities. However, in order to become price-competitive, its cost would need to be reduced significantly. Multiple cost-reduction concepts have been proposed by the manufacturing and procurement groups. An Optimization Team was also formed to lead the cost-reduction effort. However, a more systematic approach is required in order to achieve the ambitious reduction goals. The proposed solution is to create a top-down systematic cost-reduction framework used to coordinate and prioritize the team's current bottom-up approach. A top-down cost reduction strategy was developed based on UTC Otis' Octopus Fishing concept. Such methodology, heavily finance driven, systematically breaks M28 into sub-systems, and prioritizes improvement recommendations based on cost-reduction potentials. It also leverages on the wealth of knowledge from global cross-functional teams to generate explosive amount of improvement recommendations. The sub-systems were benchmarked against competitors cost structures. The framework will be linked to concepts generated from the database to create a process that combine top-down and bottom-up approaches. After tasks were prioritized using the outlined framework, a three-prong approach was implemented to enhance cost reduction capability. Manufacturing of labor intensive parts such as nacelle deflection cover was automated using CNC machines. A set of commodity purchasing strategies were formulated for forgings, avionics, raw materials, interior and composite materials. Lastly, a discrete Kaizen event was described to aid redesign-for-manufacturing.
by Yuxin Xia.
S.M.
M.B.A.
6
Luu, Henry H. T. "Airline operating cost reduction through enhanced engine health analytics." Thesis, Massachusetts Institute of Technology, 2018. http://hdl.handle.net/1721.1/119307.
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Thesis: S.M., Massachusetts Institute of Technology, Department of Aeronautics and Astronautics, In conjunction with the Leaders for Global Operations Program at MIT, 2018.Thesis: M.B.A. Massachusetts Institute of Technology, Sloan School of Management 2018 In conjunction with the Leaders for Global Operations Program at MIT
Cataloged from PDF version of thesis. "June 2018."
Includes bibliographical references (pages 108-111).
Engine Health Management (EHM) is a comprehensive maintenance service offered by engine manufacturer Pratt & Whitney (PW) to its airline customers. In its current form, engine performance is monitored through recorded physical metrics, such as gas temperature, pressure, and altitude, taken as single snapshots at various phases of flight. The advent of the Enhanced Flight Data Acquisition, Storage and Transmission (eFASTTM) system, which allows for near-continuous recording of engine metrics, provides Full-Flight Data Analytics (FFDA) that may proactively alert and recommend maintenance activity to airlines. Adopting eFASTTM may help avoid Adverse Operational Events (AOE) caused by unexpected engine failures and the associated cost burdens. With respect to operating cost, airlines standardly report Cost Per Available Seat Mile (CASM) and Cost Per Block Hour (CBH). EHM services that prevent operational disruptions can help airlines reduce these unit-cost metrics, whose scrutiny by industry analysts affect investment guidance, stock performance, and overall business outlook. In this study, the value of FFDA services to airlines is investigated on the International Aero Engines V2500, a mature engine with customers' operational histories well-documented. Using a Poisson distribution to model the occurrence of six operational disruption types-Inflight Shutdown, Aircraft-On-Ground, Aborted Takeoff, Air Turn-Back, Ground Turn-Back, and Delay/Cancellation-the cost savings potential is quantified as a function of events avoided by a hypothetical FFDA service. Airline Form 41 financial data from the Bureau of Transportation Statistics is then used to estimate the magnitude of savings on CASM and CBH retroactively for 2012-16. Results show that unit cost reductions of 0.5% to 1.5% are possible through engine event avoidance, representing savings up to $104M annually, but outcomes are highly dependent on assumptions about cost of operational disruptions for each individual carrier. Overall, a baseline model and procedure is developed for valuating FFDA and associated EHM services. Further collaboration between airlines and Pratt & Whitney on data availability and accuracy will help refine this model, which is the first to bridge publicly available airline costs with engine history data, helping stakeholders transition to an eFASTTM ecosystem that promises greater operational efficiency and safety.
by Henry H. T. Luu.
S.M.
M.B.A.
7
Payne, Jeffrey. "Optimizing fire department operations through work schedule analysis, alternative staffing, and nonproductive time reduction." Thesis, Monterey, California: Naval Postgraduate School, 2014. http://hdl.handle.net/10945/43976.
Full textAbstract:
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This thesis conducts a policy analysis exploring how current fire department policies can be modified to optimize employee availability to lead to higher staffing levels and lower sick leave and injury leave usage. Work schedule modification, alternative staffing models, and the reduction of nonproductive time through health and wellness initiatives are the three options examined in this thesis by using data from the Dayton (Ohio) Fire Department. The findings of this research are that schedule modification and the reduction of nonproductive time by initiating wellness programs may increase employee availability; alternative work schedules tended to increase injury rates and the potential for political and legal conflict. These findings should be applicable to fire departments across the country, most of whom address the same budget shortfalls and force-strength challenges.
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Hildreth, John C. "The Use of Short-Interval GPS Data for Construction Operations Analysis." Diss., Virginia Tech, 2003. http://hdl.handle.net/10919/26120.
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The global positioning system (GPS) makes use of extremely accurate measures of the time to determine position. The times required for electronic signals to travel at the speed of light from at least four orbiting satellites to a receiver on earth is measured precisely and used to calculate the distances from the satellites to the receiver. The calculated distances are used to determine the position of the receiver through triangulation.
This research takes an approach opposite the original GPS research, focusing on the use of position to determine the time at which events occur. Specifically, this work addresses the question: Can the information pertaining to position and speed contained in a GPS record be used to autonomously identify the times at which critical events occur within a production cycle?
The research question was answered by determining the hardware needs for collecting the desired data in a useable format an developing a unique data collection tool to meet those needs. The tool was field evaluated and the data collected was used to determine the software needs for automated reduction of the data to the times at which key events occurred. The software tools were developed in the form of Time Identification Modules (TIMs). The TIMs were used to reduce data collected from a load and haul earthmoving operation to duration measures for the load, haul, dump, and return activities.
The value of the developed system was demonstrated by investigating correlations between performance times in construction operations and by using field data to verify the results obtained from productivity estimating tools. Use of the system was shown to improve knowledge and provide additional insight into operations analysis studies.Ph. D.
9
Lieberman, Jeremy A. (Jeremy Alan). "Reduction of rework at a large aerospace manufacturer." Thesis, Massachusetts Institute of Technology, 2012. http://hdl.handle.net/1721.1/73417.
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Thesis (M.B.A.)--Massachusetts Institute of Technology, Sloan School of Management; and, (S.M.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering; in conjunction with the Leaders for Global Operations Program at MIT, 2012.Cataloged from PDF version of thesis.
Includes bibliographical references (p. 88-91).
It is an axiom of the manufacturing of any complex product that errors will occur that require repair or discard of said product. In building aircraft, Raptor Aerospace encounters and repairs numerous deviations from the original design drawings. This process is known as rework. Reducing the amount of rework necessary represents a substantial opportunity both for improving quality and for cutting cost. Rework can be further split into several categories, with the simplest repairs referred to as reworkable discrepancies which has been valued at over $50,000,000 per year. This thesis will present a project that began at the start of the internship, when the author was paired with a specialist from Raptor Aerospace to lead a team whose purpose was to develop an approach and implement improvements that would generate a significant reduction in rework. This process would include both physical changes to the manufacturing process and would target specific aspects of the prevailing culture at Raptor. With no existing plan for reducing rework, the two team leaders began the project by conducting a thorough analysis of existing rework data, focusing on the descriptive texts that were provided by inspectors. This analysis generated a pareto of the inspectors' words, enabling the team to identify the most common causes of rework at Raptor. Based on these results, small teams were created to perform root cause and corrective action analyses on the biggest issues. In addition to the small teams, the co-leaders also searched for solutions that would have a systemic impact on the volume of rework. To this end, an automated tool was developed that would report the rework history of every single task completed in final assembly. Within the timeframe of the internship (6.5 months), the various approaches completed by the project team produced verified annualized savings of over $2,000,000, as well as time savings of over 40 manhours per week. In addition, other efforts that were begun but not yet completed have anticipated savings of over $10,000,000. Finally, the project has produced indications of cultural improvements within Raptor Aerospace, as individuals and departments have begun volunteering to contribute and lead improvement efforts. Overall, it appears that the approaches taken by the project team have successfully launched a change initiative which could have substantial and long-lasting value to Raptor Aerospace.
by Jeremy A. Lieberman.
S.M.
M.B.A.
10
Gantner, Karl (Karl Andrew). "Production leveling and cycle time reduction in satellite manufacturing." Thesis, Massachusetts Institute of Technology, 2016. http://hdl.handle.net/1721.1/104217.
Full textAbstract:
Thesis: S.M., Massachusetts Institute of Technology, Department of Aeronautics and Astronautics, 2016.Thesis: M.B.A., Massachusetts Institute of Technology, Sloan School of Management, 2016. In conjunction with the Leaders for Global Operations Program at MIT.
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 50-52).
Reducing cycle time for geostationary communication satellites represents a major competitive advantage for manufacturers. Reducing cycle time can be done through application of lean manufacturing techniques such as production leveling, or heijunka. However, research on applying lean manufacturing to the manufacture of satellites is not straightforward as payloads vary considerably. To show the effect of production leveling on satellite manufacturing, we analyze production data recorded over a 5-year time frame from a major satellite manufacturer to propose and simulate a method for leveling production. Statistical analysis of historical cycle times was performed to identify the critical path and bottleneck in the satellite development process. Production through the bottleneck was then leveled at the maximum consistent throughput. The effect of leveling was estimated using a Monte Carlo simulation to predict the total cycle time and delivery date for each satellite. Analysis showed that the critical path ran through the development of the communications payload and the bottleneck was at the payload unit build process. The bottleneck was leveled to operate at a takt time of 2 months with 4 payloads in WIP at a time. Simulating a leveled bottleneck estimated that the total cycle time of each satellite, on average, would decrease by 1.9 months with a standard deviation of 14 days. Cycle time in the payload unit manufacturing process fell from 13 months to 8 months, with standard deviations 64 and 12 days, respectively. Over the 5-year period investigated, all satellites through the factory would have met their delivery dates while being produced to a 2 month takt. These results demonstrate that production leveling can be applied to the high-mix low volume manufacturing of geostationary communications satellites to increase efficiency and reduce cycle time. Leveling manufacturing should be a top priority for all satellite manufacturers looking to become more competitive.
by Karl Gantner.
S.M.
M.B.A.
11
Ebben, Philip T. "Congestion reduction in the Emergency Department of Massachusetts General Hospital." Thesis, Massachusetts Institute of Technology, 2018. http://hdl.handle.net/1721.1/118728.
Full textAbstract:
Thesis: S.M., Massachusetts Institute of Technology, Department of Mechanical Engineering, in conjunction with the Leaders for Global Operations Program at MIT, 2018.Thesis: M.B.A., Massachusetts Institute of Technology, Sloan School of Management, in conjunction with the Leaders for Global Operations Program at MIT, 2018.
Cataloged from PDF version of thesis.
Includes bibliographical references (page 55).
The MGH Emergency Department (ED) and General Medicine Floor currently experience heavy patient volume and rising patient wait times, despite recent capacity expansions. While several projects have been piloted to divert patients towards alternative care paths, MGH management wants to better understand what types of patients are being admitted to the hospital and what features are deterministic of patient admission. This thesis addresses this information gap by using binary logistic regression models to assess predictive and significant patient features for admission. Our analysis uses both patient demographic information and decision point data gathered in the Emergency Department of patient visits. On out-of-sample data, our predictive model achieves an area under the receiver operating characteristic of 0.82, and we conclude that the predictive features for admission are within good clinical practice. Further analysis of patient care suggests that provision of IV antibiotics in the outpatient setting could reduce MGH admissions by approximately 307 bed-days per year, with additional possible reductions in excess of 1,000 beddays for different provisions of care. We also assess the outpatient usage of MGH patients and conclude that 75 percent of cellulitis, pneumonia and urinary tract infection patients are not seeing a clinician in the outpatient setting prior to ED presentation. This analysis indicates that more proactive management of these patients could prevent both their visit to the ED and potentially their admission. We demonstrate that statistical methods based on real time patient data. can contribute to effective healthcare planning and operations.
by Philip T. Ebben.
S.M.
M.B.A.
12
Patel, Kashyap (Kashyap C. ). "Crisplant defects quantification and reduction at an amazon.com distribution center." Thesis, Massachusetts Institute of Technology, 2010. http://hdl.handle.net/1721.1/59174.
Full textAbstract:
Thesis (M.B.A.)--Massachusetts Institute of Technology, Sloan School of Management; and, (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering; in conjunction with the Leaders for Global Operations Program at MIT, 2010.Cataloged from PDF version of thesis.
Includes bibliographical references (p. 59-60).
Crisplant is a tilt-tray sortation system used in Reno (RNO 1) fulfillment center (FC) to group items by customer orders. On average., crisplant processes about 80% of the total outbound volume through its multipart operation flow. Because of high volume and complex process flow, the majority of defects, in RNO 1 FC. are seen in crisplant costing distribution center (RNO 1) significantly in labor hours. This research paper identifies and quantifies the major defects in crisplant, and outlines the solutions to reduce the cost of handling these defects in RNO 1. The project work thoroughly assesses the entire RNO 1 crisplant operations (induct, sort, pack, SLAM, and problem solve) through four-phase approach: Understand the crisplant Process Flow, Develop a Data Collection Framework, Collect and Analyze Data, and Identify/Implement Data Driven Solutions. Lean principles and methodologies were used throughout the project work especially when identifying solutions. For example, opportunities that improved the packing process were identified based on a deep-dive analysis as a part of the Kaizen study. The project results demonstrated 50% reduction in cost of handling crisplant defects in RNO l. Furthermore, it highlighted opportunities for additional savings by identifying solutions that can also be implemented in other FCs (i.e. SDF 1, TUL 1) with similar operation as RNO 1.
by Kashyap Patel.
S.M.
M.B.A.
13
Kobor, Hans P. "Closed loop supply chain waste reduction through predictive modelling and process analysis." Thesis, Massachusetts Institute of Technology, 2019. https://hdl.handle.net/1721.1/122573.
Full textAbstract:
Thesis: M.B.A., Massachusetts Institute of Technology, Sloan School of Management, 2019, In conjunction with the Leaders for Global Operations Program at MITThesis: S.M., Massachusetts Institute of Technology, Department of Mechanical Engineering, 2019, In conjunction with the Leaders for Global Operations Program at MIT
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 59-60).
Verizon distributes Customer Premises Equipment (CPE) such as set top boxes, broadband routers, and WiFi extenders to Fios customers via a variety of paths; for example: direct ship to customer (either for self-install or for later installation by a field technician), delivery via field technicians, or retail store pickup (primarily for self-install). Each method has its own benefits and shortcomings due to impacts on metrics such as inventory levels, shipping costs, on-time delivery, and system complexity. Although the majority of shipments are successfully activated in the customer's home, a non-trivial percentage results in unused returns or inventory shrinkage. These undesirable results represent a significant amount of wasted resources. This thesis is focused on identifying and realizing cost savings in the Fios supply chain through reduction in waste associated with unsuccessful shipments.
In order to effectively analyze the closed-loop supply chain, accurate and reliable process mapping is critical. Interviews with key stakeholders, together with order and shipment data analysis yielded a complete picture of the ecosystem's processes and infrastructure. Process mining techniques augmented this understanding, using event log data to identify and map equipment and information flows across the supply chain. All together this analysis is used to identify order cancellations as a key source of waste. To limit waste, it is necessary to conduct analysis both internal to Verizon's processes and externally, to determine if there are customer trends leading to order termination. Process mining was used for the internal analysis and, while it helped identify singular cases in which process abnormalities were associated with undesirable outcomes, its current form proved unsuited for root cause analysis.
Internal analysis did, however, illuminate opportunities for improvement in radio-frequency identification (RFID) usage and protocols across the supply chain. Current systems can result in poor visibility of equipment as it moves within some segments of the supply chain. The actual monetary impact is difficult to determine but likely to increase as the importance of RFID increases. External analysis is conducted through predictive modelling. Using a variety of data sources, a model with over 80% sensitivity and a low false positive rate is achieved. Operationalizing this model through real time incorporation with sales was explored but found to be overly complex. Instead, the random forest model yielded policy changes guided by the features with the highest importance. A pilot is currently in development to test the efficacy of suggested changes, as the model implies significant savings opportunity.
by Hans P. Kobor.
M.B.A.
S.M.
M.B.A. Massachusetts Institute of Technology, Sloan School of Management
S.M. Massachusetts Institute of Technology, Department of Mechanical Engineering
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Romanov, Alexander M. B. A. Massachusetts Institute of Technology. "Analysis and reduction of excess inventory at a heavy equipment manufacturing facility." Thesis, Massachusetts Institute of Technology, 2013. http://hdl.handle.net/1721.1/81016.
Full textAbstract:
Thesis (M.B.A.)--Massachusetts Institute of Technology, Sloan School of Management; and, (S.M.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics; in conjunction with the Leaders for Global Operations Program at MIT, 2013.Cataloged from PDF version of thesis.
Includes bibliographical references (p. 72-73).
The research presented in this thesis explores two hypotheses focused on excess inventory at a heavy equipment manufacturing facility. The scope of the thesis includes inventory in the form of raw materials, purchased components, and work in process parts found at the facility and in the off-site storage warehouse. The first hypothesis proposes that excess inventory at the facility has several key root causes, and that their elimination drastically reduces the accumulation rate of excess inventory. The second hypothesis proposes that a basic material review process could be effective in identifying and reducing excess inventory at the facility in a six-month timeframe. The hypotheses were tested over a six-month period at a Caterpillar Global Mining facility. The first hypothesis was not confirmed. More than twenty root causes of excess inventory accumulation were identified and no evidence was discovered that would suggest that certain root causes are dominant. The second hypothesis was supported by the findings at the facility. The organization was able to formulate a basic material review process, apply the process to the facility's inventory, and reduce excess inventory by roughly 35% over a three-month time span.
by Alexander Romanov.
S.M.
M.B.A.
15
Jane, Okiria-Ofwono Jacqueline. "An evaluation of the implementation of decentralization of the World Bank's operations of poverty reduction in Uganda." Thesis, Nelson Mandela Metropolitan University, 2012. http://hdl.handle.net/10948/d1012605.
Full textAbstract:
Continued debates on economic development, poverty eradication and the growing skeptism concerning the paradigms proposed through many decades, has led to a continued search for a paradigm that would, finally, resolve the issue of pervasive poverty in the Sub-Saharan Africa. Having implemented decentralization within government entities without any significant contribution to poverty eradication, the focus has now turned to the development agencies themselves. What are the inefficiencies in these agencies which if addressed might enable them deliver development aid more efficiently thus, providing more resources for development from being lost in the attrition of overheads? It is, therefore, argued that decentralization of development agencies will improve the efficiency and effectiveness of IFIs in delivering development aid. At the same time, decentralization reforms have been proposed as a response to the failures of highly centralized states (or organizations in this case). Empirical evidence, strongly, suggests that physical proximity and more "face-time", promotes better results-on-the-ground, delivered by staff who are better attuned to local conditions and have a better understanding of the client and their development agenda. But, will decentralization alone solve the issue of pervasive poverty? This research recognises that the factors affecting poverty are diverse and intricate and isolating just one part of the puzzle is not enough. Nevertheless, it is argues that decentralization, has a positive impact on poverty reduction thus, this study presents both practical and theoretical considerations from which policy measures can be derived. This thesis focused on establishing how the World Bank, changed its strategies through the implementation of decentralization of its operations as proposed in the ‗Strategic Compact‘, renewed the way it worked in order to maintain its relevance in the development world. The World Bank President, James Wolfensohn, proposed the Compact as a solution to the organization‘s self diagnosis that it was in distress, in a state of possible decline and was not fulfilling its mission of poverty eradication. This research, using Uganda Country Office as a case study, undertook, mainly, a qualitative review of the overall strategy of decentralization and its implementation organization wide and specifically, in Uganda. The research examined how the implementation of the strategy impacted on poverty trends in Uganda. This research found that the decentralization strategy was, fundamentally, the right one to deliver better results of the Bank‘s mission of ‗fighting poverty for lasting results‘ and its vision of ‗A World Free of Poverty‘. Contrary to the popular notion that the World Bank has been, largely ineffective in the delivery of its mission and its decentralization strategy just another one of its 'shams‘, this research established that the implementation of the strategy, although not having a direct or causal relationship, did have positive impact on poverty alleviation in Uganda. This study, therefore, makes a case for decentralization of donor organizations as a means of better delivery of the poverty eradication agenda in the developing world. The benefits though hard to measure in monetary terms are, nevertheless, real in terms of faster and better quality engagement with the clients which in turn, result into better delivery of services and programmes.
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Pellegrini, Jacob Philip. "Reduction of total production cost through the use of safety stock and process improvements." Thesis, Massachusetts Institute of Technology, 2019. https://hdl.handle.net/1721.1/122569.
Full textAbstract:
Thesis: M.B.A., Massachusetts Institute of Technology, Sloan School of Management, 2019, In conjunction with the Leaders for Global Operations Program at MITThesis: S.M., Massachusetts Institute of Technology, Department of Mechanical Engineering, 2019, In conjunction with the Leaders for Global Operations Program at MIT
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 76-77).
In an ideal production system, supply exactly meets demand. Instantaneous, correct quantities arrive exactly at the right location when needed. However, real-world production systems often have variability- a change in the quantity demanded, a broken part, a shipping delay for a snow storm. The variability can be random, so companies are left with a dilemma: too little inventory buffer and a shortage may occur; too much inventory and capital is unnecessarily tied up in inventory sitting on the shelves. Using research conducted at the Boeing 737 program as a case study, this thesis proposes the application of a multi-step approach to optimize the total cost of the production system, balancing holding cost (inventory) with the disruption cost of a shortage. The initial pilot shows that small increases in inventory can have an order of magnitude of cost avoidance. The methodology includes system observation, qualitative interviews with Boeing employees, quantitative data gathering and analysis, proposed changes, and measured results. First, the historical supply and demand variability of the system is identified. Second, the cost of a shortage is estimated for the system. Next, an analytical approach to set safety stock levels is applied to balance the cost of inventory held with the cost of a shortage. By reducing the variability in the system, inventory levels can be reduced while maintaining the service levels. This process is then repeated at regular intervals to optimize the total cost of the system, balancing inventory holding cost and the disruption cost of a shortage.
by Jacob Philip Pellegrini.
M.B.A.
S.M.
M.B.A. Massachusetts Institute of Technology, Sloan School of Management
S.M. Massachusetts Institute of Technology, Department of Mechanical Engineering
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Sedig, Ludwig, and Niclas Sundman. "Reducering av transportsträckor i lagerverksamhet med hjälp av ABC-klassificerad artikelplacering." Thesis, Tekniska Högskolan, Högskolan i Jönköping, JTH, Industriell organisation och produktion, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-31024.
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Purpose – The purpose of this study is to investigate how ABC-classified article placement can reduce transport distances within warehouse operations, which do not use volume-based article placement. Based on the purpose, two research questions have been formulated: [1] How can an ABC-classified article placement be established in order to minimize transport distances within warehouses? [2] How much can transport distances be reduced by using an ABC-classified article placement instead of a non-volume based storage? Method – The methods that have been used to collect data have been a case study and a literature review. The case study has been performed on Sherwin-Williams’ distribution centre in Nässjö and has mainly been based on two months of picking data. Interviews and observations have supplemented the document study. The literature review has resulted in a theoretical framework in which the relevant theories of the study have been presented. The collected data was analysed by comparing the different results against each other. Further comparisons analysed the empirical data against the theoretical framework. Findings – The study has resulted in a model of how ABC-classified article placement with the purpose to reduce transport distances can be designed. The model is based on a few steps that are: pilot study, performance of an ABC-analysis based on the articles picking rate, and zone division. According to the case study ABC-classified article placement can reduce up to 35 % of internal transportation distances and according to the theoretical framework of up to 55 %. Implications – Warehouses that want to use the study can proceed from the steps presented in the analysis section. Furthermore, the practical implications of the study results in a system configuration and the movement of goods to the introduction of the ABC-classified article placement. The study implies theoretically that the volume-based article placement minimizes transport distances. The existing theories stating this is evidenced in this study which also shows that warehouses with less skewed ABC-curves can benefit from placing high frequency goods near the loading area. The study contributes with a new model that has been developed by compiling theories in the studied area. Limitations – The study has been limited to a single case study. The calculations made in the study have excluded items that require special storage, small package picking and distance between the pallets that are retrieved together. Transport distances have been calculated from the loading area and has excluded the distance between the racks and unload area.
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Stoddard, Steven J. "Project process mapping : evaluation, selection, implementation, and assessment of energy cost reduction opportunities in Manufacturing." Thesis, Massachusetts Institute of Technology, 2012. http://hdl.handle.net/1721.1/73418.
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Thesis (M.B.A.)--Massachusetts Institute of Technology, Sloan School of Management; and, (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering; in conjunction with the Leaders for Global Operations Program at MIT, 2012.Cataloged from PDF version of thesis.
Includes bibliographical references (p. 46-48).
Company X uses large amounts of electricity in its manufacturing operations. Electricity prices at selected plants in the company's Region 1 territory rose by over 350% between 2000 and 2011, in part due to increasing reliance on high-cost fossil fuels. A focus on reducing these costs has identified numerous energy-saving projects in recent years, but with mixed implementation and performance results between the different plants in the region. Consequently, there is both a need to reduce exposure to high electricity prices and an opportunity to better share best-use practices between plants. This paper has two focuses: identifying and quantifying energy cost-reduction opportunities, and mapping the value-streams for the decision-making and implementation process for energy savings projects. From this Value Stream Map, recommendations are made for a new process that can be standardized and rolled out to other sites in the region. During the first phase of the project, data gathered from utility bills, power meters, and production records are used to identify the best opportunities for energy reduction within the plants. Using this technique, 7 GWh/year of potential energy cost savings are identified via reduced downtime, lighting motion detectors, high-efficiency lighting, and negotiable changes to energy contracts. For the benchmarking phase, the historical record of identified energy projects is compared with the number of projects actually implemented. An observational study of the local LEAN team from one plant is combined with interviews of engineers, managers, and financial analysts to build a process map of both the current and former processes for energy project identification, evaluation, and implementation. The results show a reduction in process steps and a step-change increase in the number of energy projects implemented. A key feature of the new approach is the creation of a dedicated energy team within the existing LEAN program. It is believed that emulating this integration of energy and LEAN at other sites will yield cost reductions as well. To follow up this work, a pilot study modeling this program at another site is recommended before further expansion to the rest of the region.
by Steven J. Stoddard.
S.M.
M.B.A.
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Giluk, Tamara L. "Mindfulness-based stress reduction: facilitating work outcomes through experienced affect and high-quality relationships." Diss., University of Iowa, 2010. https://ir.uiowa.edu/etd/674.
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Mindfulness is a quality of consciousness that consists of purposeful attention to and awareness of the present moment, approached with an attitude of openness, acceptance, and nonjudgment. Research evidence shows that mindfulness has positive effects on mental health and psychological well-being, physical health, and quality of intimate relationships. However, few researchers have studied the effects of mindfulness in a work setting. In this project, I expanded previous research by exploring how mindfulness, as developed in a mindfulness-based training program, affects the workplace outcomes of performance and citizenship behavior. I proposed that these effects are mediated through the positive effects of mindfulness on one's experienced affect and one's work relationships. I also examined interdependence as a moderator of the relationship quality-work outcomes relationship. The research study employed an experimental group of participants in a mindfulness-based program and a nonequivalent control group to test the specific hypotheses. Data were provided by multiple sources: mindfulness, affect, and role interdependence by study participants; relationship quality by coworkers; performance and citizenship behavior by supervisors. Analytic strategy was comprised of correlational analysis and regression as well as analytical procedures for moderated mediation. The mindfulness-based programs were effective in increasing mindfulness, particularly for those participants who were lower in mindfulness prior to program participation. Participants also experienced improved affect. However, the proposed model relating mindfulness to work outcomes was not supported. Mindfulness was significantly related to positive and negative affect as predicted; however, mindfulness was not significantly correlated with relationship quality or job performance. Its significant relationship with citizenship behavior was in the opposite direction as hypothesized. In the full model, coefficients for mindfulness, experienced affect, relationship quality, and role interdependence in the prediction of job performance and citizenship behavior were not significant. Additionally, interdependence did not interact with relationship quality to predict work outcomes. Implications of the study for mindfulness-based programs in work settings and for future research are discussed.
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Ziegler-Barranco, Ana, Luis Mera-Barco, Vidal Aramburu-Rojas, Carlos Raymundo, Nestor Mamani-Macedo, and Francisco Dominguez. "SCAT Model Based on Bayesian Networks for Lost-Time Accident Prevention and Rate Reduction in Peruvian Mining Operations." Springer, 2020. http://hdl.handle.net/10757/656168.
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El texto completo de este trabajo no está disponible en el Repositorio Académico UPC por restricciones de la casa editorial donde ha sido publicado.Several factors affect the activities of the mining industry. For example, accident rates are critical because they affect company ratings in the stock market (Standard & Poors). Considering that the corporate image is directly related to its stakeholders, this study conducts an accident analysis using quantitative and qualitative methods. In this way, the contingency rate is controlled, mitigated, and prevented while serving the needs) of the stakeholders. The Bayesian network method contributes to decision-making through a set of variables and the dependency relationships between them, establishing an earlier probability of unknown variables. Bayesian models have different applications, such as diagnosis, classification, and decision, and establish relationships among variables and cause–effect links. This study uses Bayesian inference to identify the various patterns that influence operator accident rates at a contractor mining company, and therefore, study and assess the possible differences in its future operations.
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Al-Mulla, Khalil Ibrahim. "Stress Reduction Strategies for Improving Private Security Officer Performance." ScholarWorks, 2018. https://scholarworks.waldenu.edu/dissertations/6298.
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The impact of occupational stress on employees' health and work performance costs U.S. companies $300 billion annually; work-related stress is an issue for private security organizations all over the world. The purpose of this single case study was to explore strategies private security organizational leaders used to mitigate private security officers' occupational stress. The study participants were 4 leaders of a private security organization in Bahrain who had a minimum of 5 years of experience in the private security field and had addressed occupational stress successfully. The human capital theory was the conceptual framework used for this study. Data were collected using semistructured interviews and review of archival documents. Yin's 5-step data analysis plan was applied to the data to generate 4 themes: private security occupational stressors, occupational stress reduction practices, leaders-officers open communication, and health protection policies. The identification and development of job stressor mitigation strategies has multiple implications for positive social change including protecting employees' well-being and increasing their working performance, productivity, and business success. Improving work performance and productivity produces opportunities for employment and supports economic growth and community goodwill. The practices of a successful organization positively influence the society by providing jobs and capital investments, which can improve the quality of life in the community.
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Resch, Kevin (Kevin Scott). "An analysis of incentive strategies for single-source suppliers to drive cost reduction." Thesis, Massachusetts Institute of Technology, 2011. http://hdl.handle.net/1721.1/66053.
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Thesis (M.B.A.)--Massachusetts Institute of Technology, Sloan School of Management; and, (S.M.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science; in conjunction with the Leaders for Global Operations Program at MIT, 2011.Cataloged from PDF version of thesis.
Includes bibliographical references (p. 54-55).
An organization's decision on which aspects of its operations to outsource represents a key, strategic issue that should be based on maximizing performance throughout the entire value chain. In certain instances strategic outsourcing decisions make it ideal for firms to source from one particular supplier. Singlesource relationships, in particular, necessitate strategic contract development to ensure incentives are aligned throughout the value chain. Much of the existing research in contract development focuses on mitigating fluctuations in demand. Forecasting demand is highly uncertain and can lead to inefficiencies throughout the value chain that contracts can alleviate. However, the defense industry typically has low uncertainty in demand, which offers a unique environment to study contract development. This thesis focuses on contract development with certain demand through case studies in the defense industry. The essence of this thesis revolves around a strategic framework for developing contracts. This framework begins with a discussion of methods for performing a strategic analysis of suppliers. Next an overview of investigating supplier alternatives is provided. The framework then addresses the execution of a contract, which includes writing and negotiating the contract. Finally, contract maintenance is discussed, which includes contract validation as well as managing latent concerns. After the framework is laid out, four different single-source supplier relationships are analyzed. Each of these supplier relationships is investigated to understand the motivation for initiating these particular relationships. The four supplier case studies revolve around the issues of supplier investment costs, internal competition, commodity negotiations, and supplier power. After each case study, the pertinent aspects of the contract development framework are applied to the specific supplier relationship and conclusions are drawn.
by Kevin Resch.
S.M.
M.B.A.
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Sullivan, Bailey Ann. "The effectiveness of alfalfa, nutrient model, and vegetative filter strips in reduction of nonpoint source pollution." Thesis, Manhattan, Kan. : Kansas State University, 2007. http://hdl.handle.net/2097/359.
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Millerd, Paul M. B. A. Massachusetts Institute of Technology. "Driving cycle time reduction through an improved material flow process in the electronics assembly manufacturing cell." Thesis, Massachusetts Institute of Technology, 2012. http://hdl.handle.net/1721.1/73395.
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Thesis (M.B.A.)--Massachusetts Institute of Technology, Sloan School of Management; and, (S.M.)--Massachusetts Institute of Technology, Engineering Systems Division; in conjunction with the Leaders for Global Operations Program at MIT, 2012.Cataloged from PDF version of thesis.
Includes bibliographical references (p. 62).
Many companies have implemented lean and six sigma programs over the past twenty years. Lean has been a proven system that has eliminated waste and created value at many companies throughout the world. Raytheon IDS's lean program, "Raytheon Six Sigma" became a top priority in the past ten years at the Integrated Air Defense Center (IADC) in Andover, MA. However, as Raytheon's corporate goals state, they want to take this further and bring "Raytheon Six Sigma" to the next level, fully engaging customers and partners. A focus of this continuous improvement effort was the Electronics Assembly Rack manufacturing cell, which was experiencing high levels of cycle time variability. To help reduce cycle times within the cell, a continuous improvement project was undertaken to improve the material flow process. A current state analysis of the process showed an opportunity to improve process standardization and prioritization while lowering inventory levels. In addition to working with managers from EA to evaluate the material flow process, a kitting cart was developed with a cross functional project team to serve as a tool to help improve the process. Although the improvements were not rolled out to the entire cell during the project, a successful pilot was conducted that helped improve engagement with operators and create a path for future success.
by Paul Millerd.
S.M.
M.B.A.
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Nabergall, Lukas. "Patterns in Words Related to DNA Rearrangements." Scholar Commons, 2017. http://scholarcommons.usf.edu/etd/6912.
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Patterns, sequences of variables, have traditionally only been studied when morphic images of them appear as factors in words. In this thesis, we initiate a study of patterns in words that appear as subwords of words. We say that a pattern appears in a word if each pattern variable can be morphically mapped to a factor in the word. To gain insight into the complexity of, and similarities between, words, we define pattern indices and distances between two words relative a given set of patterns. The distance is defined as the minimum number of pattern insertions and/or removals that transform one word into another. The pattern index is defined as the minimum number of pattern removals that transform a given word into the empty word. We initially consider pattern distances between arbitrary words. We conjecture that the word distance is computable relative the pattern αα and prove a lemma in this direction. Motivated by patterns detected in certain scrambled ciliate genomes, we focus on double occurrence words (words where every symbol appears twice) and consider recursive patterns, a generalization of the notion of a pattern which includes new types of words. We show that in double occurrence words the distance relative so-called complete sets of recursive patterns is computable. In particular, the pattern distance relative patterns αα (repeat words) and ααR (return words) is computable for double occurrence words. We conclude by applying pattern indices and word distances towards the analysis of highly scrambled genes in O. trifallax and discover a common pattern.
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Avdic, Aldin, and Johan Kling. "Ledtidsreducering vid Saab Training Systems Ab : Lead time reduction at Saab Training Systems AB." Thesis, Jönköping University, JTH, Industrial Engineering and Management, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-1032.
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Detta examensarbete är utfört på Saab Training Systems AB i Huskvarna. Saab Training Systems utvecklar, tillverkar och säljer kompletta militära träningssystem.
Syftet med arbetet var att minska ledtiderna, då korta leveranstider blir ett allt viktigare konkurrensmedel. Arbetet innebar en kartläggning av nuvarande reserv- och reparationsflöde samt att identifiera problem och komma fram till förbättringsförslag.
Vidare har vi studerat reservdelslagrets lagernivå och dess kapitalbindning.
Arbetet genomfördes med hjälp av intervjuer med berörd personal, observationer, enkätundersökning samt statistiska studier. Vi har även arbetat med Supply Chain Operations Reference Model som är en öppen referensmodell med vars hjälp man kan kartlägga, förändra och optimera sin verksamhet.
Saab Training Systems har som mål att ledtiderna för reservdelsflödet och reparationsflödet skall vara 14 dagar, men i själva verket är det inte så. Dessa ledtider är idag längre, hur långa är dock oklart.
De långa ledtiderna beror främst på att i flödena förekommer det mycket passiv tid. Tiden uppstår bland annat i väntan på transport men även som en konsekvens av att företaget för tillfället har mycket att göra.
För att reducera ledtiderna bör Saab Training Systems i första hand reducera den passiva tiden.
Saab Training Systems bör sänka sina lagernivåer för att frigöra bundet kapital vilket leder till att de minskar risken att produkterna minskar i värde eller blir inkuranta.
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Le, Hesran Corentin. "Integrating waste minimization concerns in operations scheduling." Thesis, Lyon, 2019. http://www.theses.fr/2019LYSEI111.
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Confronté à des enjeux économiques et environnementaux croissants, le monde industriel doit s’adapter afin de répondre aux problématiques actuelles. La production industrielle est responsable de 83% de la production mondiale de déchets solides et de 40% de la consommation d’énergie, et l’ordonnancement s’avère être un levier prometteur pour agir sur ces enjeux. L’état de l’art réalisé montre que les travaux de recherche traitent en majorité des enjeux énergétiques. Cette thèse propose de s’intéresser à la problématique suivante : Comment intégrer la réduction des déchets dans l’ordonnancement des opérations ? L’état de l’art sur le sujet faisant émerger une terminologie disparate, une classification est proposée pour unifier ce champ de recherche hétérogène. Pour répondre à la problématique, nous proposons une méthodologie combinant le suivi des flux de matière avec les paramètres d’ordonnancement pour permettre l’identification des opportunités de réduction de la génération de déchets par l’ordonnancement, et la caractérisation du problème d’ordonnancement correspondant. Une étude de cas valide la méthodologie et l’intérêt des résultats obtenus. En se basant sur ces résultats, un problème d’ordonnancement bi-objectif machine-unique avec réentrance dans un contexte de fabrication à la commande est modélisé en programmation linéaire. Deux méthodes de résolution ‒ exacte et métaheuristique ‒ sont comparées et démontrent le potentiel de l’ordonnancement pour la réduction de la génération de déchets industriels. Cette résolution fournit aux preneurs de décision des solutions alternatives adaptées, et permet une réduction des déchets significative en contrepartie d’une augmentation de stock limitée. Ces travaux se concentrant sur les déchets ouvrent la voie à d’autres enjeux environnementaux comme l’intégration des enjeux énergétiques et d’émissions atmosphériques, et à la considération du critère social afin d’englober les trois piliers du développement durableFaced with growing environmental and economic concerns, the industrial world needs to adapt in order to tackle these issues. Industrial production is responsible for 83% of the global solid waste production and 40% of worldwide energy consumption. Operations scheduling appears to be a promising tool to address both the environmental and economic aspects of this problem. A literature review shows that numerous studies have been focusing on reducing energy consumption. This dissertation focuses on a relatively nascent field, namely the topic of waste generation minimization through operations scheduling. The motivating research question can be formulated as: How to integrate waste minimization into operations scheduling? A state-of-the-art on the subject shows a heterogeneous field with a disparate terminology, and a classification scheme is proposed to help unify research on this topic. To answer the research question, a methodology combining flow assessment tools and scheduling parameters is proposed, which enables the identification of waste-minimizing scheduling opportunities in a production system and the characterization of the corresponding scheduling problem. A case study is carried out and validates the applicability of this methodology and the interest of the results it provides. Based on those results, a single-machine waste-minimizing scheduling problem with reentrance in a make-to-order context is modeled using linear programming. Two solving approaches – one exact and one metaheuristic – are compared, and highlight the potential of operations scheduling to reduce industrial waste. Alternative solutions provide relevant trade-offs to decision-makers, offering significant waste reduction in return for a limited increase in inventory. As this methodology focuses on waste, it paves the way for the integration of new environmental aspects such as energy consumption and atmospheric emissions, as well as the social criteria in order to fully encompass the triple bottom line of sustainable development
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Blidholm, Gustaf, and Mathias Johnson. "The adoption of distributed ledger technology in trade and export finance operations of Swedish banks." Thesis, KTH, Industriell ekonomi och organisation (Inst.), 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-241120.
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Centralized data storage and reconciliation by trusted intermediaries has historically put financial systems in the hands of a single central parties. The emergence of bitcoin and blockchain, combined with the 2008 financial crisis, has shifted the Swedish financial sector’s traditional perspectives on democratization, centralization, transparency and automation. Trade and export finance is one of many sectors investigating how blockchain and distributed ledger technology can be used other than as a digital currency system. Swedish trade and export finance connects importers, exporters, banks, credit providers, customs, and transporters into a fragmented and complex process with many stakeholders. Sweden further has a history of quickly adopting technological innovations. Banks therefore face a dynamic environment and an inconsistent, manual operative process that removes profitability incentives in providing small enterprises with credit. The adoption of DLT could provide efficiency gains and cost savings in administration, communication, reconciliation and accounting. In this thesis, the costs, benefits, and remaining barriers of implementing distributed ledger technology in Swedish trade finance are identified. Further, Swedish contextual factors’ effect on the rate of adoption is addressed. The chosen methodology of deep interviews and thorough studying of literature provides an assessment of the potential transition dynamics, forming a foundation for future investment decisions. The conclusions drawn suggest that the main costs related to adoption lie in research and development and implementation. R&D costs for distributed ledgers in the Swedish financial sector during 2019 were approximated to USD 40 million. The main benefits of automation, efficiency and reduced level of complexity were concluded to likely outweigh the costs within approximately ten to twenty years. Experience will allow companies to optimize governance structures and consensus mechanisms, while learning to expose parts of networks into public space. The innovative, adaptive Swedish market environment presumably enables faster than average diffusion of innovation, while remaining barriers in cooperation, trust, interoperability and regulation may extend the adoption process
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Di, Netta James Dominick. "The Mechanics and Fixed Operations of Human Experience." UNF Digital Commons, 2016. https://digitalcommons.unf.edu/etd/648.
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This paper will use the natural laws of the universe and amassed evidence to support a dynamic systems theory approach to explain the mechanics and fixed operations of the human experience taking place inside a causally determined universe without the possibility of free will. By reductionary methods, the universe and all its’ contents, including human agents, will be exemplified as complex dynamic systems. In so doing, the human experience is reduced to being comprised of information acting and reacting with other information existing in the universe, specifically ideas. Allowing ideas to take on a physical manifestation shows how the feedback of information directly results in the rise of human consciousness and the sensation of control and volition over actions. Thus, the methods and philosophies used in this paper will set out to rebut metaphysical libertarian views asserting alternative possibilities by way of Rollback Arguments and two other libertarian arguments raised by Alfred R. Mele. This paper aims to provide a description and deeper appreciation for the mechanics and fixed operations of the human experience in a universe where free will is nonexistent.
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Fisher, Daniel C. "PREPARATION AND APPLICATION OF CATALYSTS FOR THE STEREOSPECIFIC REDUCTION AND PHOTOOXYGENATION OF OLEFINS IN CONTINUOUS OPERATIONS: A NOVEL METHOD FOR THE PRODUCTION OF ARTEMISININ." VCU Scholars Compass, 2017. https://scholarscompass.vcu.edu/etd/5159.
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Over the last two centuries, the discovery and application of catalysts has had a substantial impact on how and what chemicals are produced.Given their broad significance, our group has focused on developing new catalyst systems that are recoverable and reusable, in an attempt to reduce concomitant costs.
Our efforts have centered on constructing a recyclable chiral heterogeneous catalyst capable of effecting asymmetric hydrogenations of olefins with high stereoselectivity. A class of phosphinoimidazoline ligands, developed by researchers at Boehringer-Ingelheim, known as BIPI ligands, have proven efficacious in the asymmetric reduction of alkenes. However, these chiral ligands are homogeneous and coordinated to precious metals, rendering them irrecoverable and expensive. To address these issues, our group has derivatized the BIPI ligand-metal complex and immobilized it to the surface of graphene oxide as well as polystyrene. Their efficacy and recyclability toward the asymmetric hydrogenation of a functionalized olefin have been evaluated.
Another facet of our work has included developing a cost effective synthetic process to artemisinin, the gold standard drug in the treatment of malaria.As a natural product, artemisinin’s worldwide supply remains highly unpredictable, contributing to great price volatility.Combining the benefits of catalysis and the advantages of continuous flow chemistry, our research has sought to develop an economical approach to convert a biosynthetic precursor, artemisinic acid, to artemisinin in three chemical transformations.
High-throughput experimentation allowed us to screen a prodigious number of catalysts and identify those effective in the asymmetric hydrogenation artemisinic acid to dihydroartemisinic acid, the first step in the transformation. This screening directed us to an inexpensive, heterogeneous ruthenium catalyst. The second step of the process includes the photooxygenation of dihydroartemisinic acid, which involves photochemically generated singlet oxygen. We have evaluated a commercially available heterogeneous photocatalyst packed in a transparent bed, surrounded by light emitting diodes in the continuous photooxygenation of dihydroartemisinic acid to dihydroartemisinic acid hydroperoxide. The third and final step, an acid induced hock cleavage, initiates an intricate cascading reaction that installs an endoperoxide bridge to deliver artemisinin. Our process afforded a 57% yield from dihydroartemisinic acid to artemisinin.
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Anosike, Nnamdi Benedict. "Technoeconomic evaluation of flared natural gas reduction and energy recovery using gas-to-wire scheme." Thesis, Cranfield University, 2013. http://dspace.lib.cranfield.ac.uk/handle/1826/8625.
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Most mature oil reservoirs or fields tend to perform below expectations, owing to
high level of associated gas production. This creates a sub-optimal performance
of the oil production surface facilities; increasing oil production specific
operating cost. In many scenarios oil companies flare/vent this gas. In addition
to oil production constraints, associated gas flaring and venting consists an
environmental disasters and economic waste. Significant steps are now being
devised to utilise associated gas using different exploitation techniques. Most of
the technologies requires large associated gas throughput.
However, small-scale associated gas resources and non-associated natural gas
reserves (commonly referred to as stranded gas or marginal field) remains
largely unexploited. Thus, the objective of this thesis is to evaluate techno-
economic of gas turbine engines for onsite electric power generation called gas-
to-wire (GTW) using the small-scaled associated gas resources. The range of
stranded flared associated gas and non-associated gas reserves considered is
around 10 billion to 1 trillion standard cubic feet undergoing production decline.
The gas turbine engines considered for power plant in this study are based on
simple cycle or combustion turbines. Simple cycle choice of power-plant is
conceived to meet certain flexibility in power plant capacity factor and
availability during production decline. In addition, it represents the basic power
plant module cable of being developed into other power plant types in future to
meet different local energy requirements.
This study developed a novel gas-to-wire techno-economic and risk analysis
framework, with capability for probabilistic uncertainty analysis using Monte
Carlo simulation (MCS) method. It comprises an iterative calculation of the
probabilistic recoverable reserves with decline module and power plant
thermodynamic performance module enabled by Turbomatch (an in-house
code) and Gas Turb® software coupled with economic risk modules with
@Risk® commercial software. This algorithm is a useful tool for simulating the
interaction between disrupted gas production profiles induced by production
decline and its effect on power plant techno-economic performance over
associated gas utilization economic life. Furthermore, a divestment and make-
up fuel protocol is proposed for management of gas turbine engine units to
mitigate economical underperformance of power plant regime experienced due
to production decline.
The results show that utilization of associated gas for onsite power generation is
a promising technology for converting waste to energy. Though, associated gas
composition can be significant to gas turbine performance but a typical Nigerian
associated gas considered is as good as a regular natural gas. The majority of
capital investment risk is associated with production decline both natural and
manmade. Finally, the rate of capital investment returns decreases with smaller
reserves.
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Itoya, Emioshor. "Carbon emissions evaluation for highway management and maintenance." Thesis, Loughborough University, 2012. https://dspace.lboro.ac.uk/2134/12143.
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Highway clients are increasingly concerned with the environmental consequences and sustainability implications of their highway maintenance service. This is because the service consumes a significant amount of natural resources, is financial and energy-intensive and is a large Greenhouse gas (GHG) emitter responsible for global warming and climate change. This has placed the highway maintenance sector, including its supply chain under increasing pressure to deliver well-maintained low-carbon maintenance service, whilst addressing its climate change impacts. The highway stakeholders increasing focus on carbon footprinting is a direct response to the legal obligation presented by the enactment of the UK s Climate Change Act (2008) and the Carbon Reduction Commitments. Investment decisions on highway infrastructure must now account for carbon and financial costs in a balanced manner. Highway clients now require their supply chains to demonstrate the capacity to reduce both direct and indirect carbon, and provide carbon footprint information relating to the work done or being tendered for. This is driving the sector to re-think its business operations within environmental, economic and social limits, which inherently presents risks and opportunities poorly understood by the stakeholders. It requires an in-depth understanding of the business operations, inputs and outputs. These business requirements are compounded given the lack of an agreed industrial methodology standard focusing on carbon footprinting, the knowledge and skill gaps, system boundary definitions, credible industrial data and their collection approach. The aim of this study is to develop a project-focused and process-based carbon footprinting methodology that includes a decision-support and carbon management tool to assist carbon management decision-making in highway maintenance planning and operation. This study then explored how the PAS2050 protocol can enhance the highway maintenance service delivery carbon footprinting and identify opportunities for reduction. It briefly reviews carbon emissions performance and the UK s highway maintenance sector, and developed a methodological framework that includes a carbon evaluation tool (the sponsor s business focus tool) based on the PAS2050 protocol. The framework developed is specific to highway maintenance planning and operation. It offers a carbon Life Cycle Assessment (LCA) tool that can identify emission hotspots across the process value chain, and inform a carbon reduction hierarchy. The implementation of the PAS2050-compliant methodology framework and the carbon evaluation tool for core highway maintenance processes (for example, pavement resurfacing, pavement marking, bulk lamp replacement and grass cutting), in addition to carbon footprinting across different site locations (urban, semi-urban and rural) are presented. The results indicate that materials production and their delivery to site (embodied carbon) are areas of carbon hotspots. This represents an important decision point for highway designers, managers and maintainers in order to deliver low-carbon service. These carbon hotspots suggest a less energy-intensive or green materials manufacturing process, responsible sourcing, use of recycled and secondary materials sourced locally (closer to sites) and delivered in bulk. The step-by-step carbon footprinting approach presented in this study is unique. It can be used by other sectors within the built environment as a pragmatic means of identifying and prioritising areas of potential carbon reduction through informed decision-making.
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Schiller, Rodrigo Achilles. "Análise da eficiência energética em navios mercantes e estudo de caso do consumo de combustível em navio aliviador do tipo Suezmax." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/3/3135/tde-03032017-135911/.
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A necessidade de redução do consumo de combustíveis fósseis, devido ao cenário atual de tentar frear os efeitos do aquecimento global e de reduzir a poluição atmosférica, vem ditando uma série de transformações no setor de transporte naval. Este trabalho apresenta, inicialmente, as mudanças no âmbito normativo na questão do controle de emissões de poluentes e de eficiência de consumo de combustíveis em navios mercantes. Em seguida, com foco nas embarcações existentes, são apresentadas as principais técnicas operacionais com grande potencial de redução de consumo de combustível, destacando o método da redução da velocidade de navegação que, corretamente aplicado, tem impacto positivo tanto na redução dos custos operacionais, quanto no aumento expressivo de eficiência energética. Foi realizada uma análise numérica da variação do consumo de combustível em função da velocidade de um navio petroleiro Suezmax, adaptado para operações de alívio em plataformas do tipo FPSO em águas brasileiras. Com isso, estimou-se o potencial de aumento da eficiência energética da embarcação a partir de pequenas reduções de velocidade, e discutiu-se as possíveis aplicações desta melhoria, a partir do perfil operacional característico do navio tipo, de modo a não causar impacto econômico na operação. O estudo, ainda, avaliou a aplicação de duas metodologias numéricas diferentes, uma baseada apenas em equações de regressão, semi-empírica, e outra utilizando simulações de CFD para a estimativa de parâmetros sensíveis a forma do casco e de grande relevância para a determinação dos consumos característicos, analisando imprecisões e impactos no resultado final.The need to reduce fossil fuels consumption due to the current scenario of trying to restrain global warming effects and reduce air pollution is dictating a series of transformations in shipping. This study introduces, at first, the changes of the regulatory framework concerning gas emissions control and fuel consumption efficiency on merchant ships. Secondly, the main operational procedures with high potential reduction of fuel consumption are discussed, with focus on existing vessels, using ship speed reduction procedure. This procedure shows the positive impacts on both operating costs reduction and also on energy efficiency increase if correctly applied. Finally, a numerical analysis of the fuel consumption variation with the speed was carried out for a Suezmax class oil tanker, which has been adapted to oil offloading operations for FPSOs in Brazilian offshore oil production systems. In this analysis, the discussions about the variations of vessel energy efficiency from small speed rate reductions and the possible applications of this improvement, taking into account the typical operating profile of the vessel in such a way to have significant economic impacts on the operation. This analysis also evaluated the application of two different numerical methods: one based only on regression equations produced by existing data, semi empirical method, and another using a CFD simulations for estimating the hull shape parameters that are most relevant for determining fuel consumption, analyzing inaccuracies and impact on the final results.
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Simon, Jason E. "Effects of Multimodal Police and Community Development Interventions on Violent Crime in a Target Area of Youngstown, Ohio." Youngstown State University / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=ysu1577807036428137.
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Tverdal, Martin. "Operating system directed power reduction on EFM32." Thesis, Norwegian University of Science and Technology, Department of Computer and Information Science, 2010. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-11026.
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Power consumption has become a major concern of embedded systems.Currently FreeRTOS wastes a power waking up regularly to keep track of time.In this work FreeRTOS is modified to sleep when there is no work for the CPU to be done.Timekeeping while sleeping is done by a low frequency oscillator, consuming very little power.Drivers for peripherals have been developed, in order to optimise power consumption even more. Battery life time has been increased from 56 hours to 1867 hours for a simple self made benchmark.The goal is to get the changes into the official FreeRTOS distribution, but it has not been accepted yet.However, a customer of Energy Micro has started to develop an application based on this design.
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He, Haifeng. "Memory Footprint Reduction of Operating System Kernels." Diss., The University of Arizona, 2009. http://hdl.handle.net/10150/196010.
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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%).
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Richardson, Samuel Francis. "Strategies for Improving Energy Conservation on a Military Installation." ScholarWorks, 2018. https://scholarworks.waldenu.edu/dissertations/5518.
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Energy is an essential component required to execute missions throughout military organizations. Failing to sustain energy efficiency in military units could cause mission failures throughout the Department of Defense. As a result, efficient energy management has become a major priority for Air National Guard units as well as other military organizations around the globe. The purpose of this qualitative single case study was to gain an understanding of strategies used by front-line military supervisors to reduce energy consumption through behavioral change on a military installation located in Maryland. The central question explored strategies that front-line military supervisors use to change behaviors to reduce energy consumption on a military installation. The conceptual frameworks included the energy cultures framework, Hersey and Blanchard's situational leadership theory, Adam's equity theory, Herzberg's two-factor theory, and Vroom's expectancy theory. Research data were obtained during a 7-day period from 15 front-line military supervisors in a military unit. Participants were required to have a satisfactory evaluation performance report and be a front-line military supervisor in the Air National Guard unit being studied. Braun and Clarke's 6-phase thematic analysis technique was administered to analyze the data. There were 6 emergent themes identified from the focus group data: (a) environmental preservation, (b) sustainable practices, (c) funds, (d) proactive leadership, (e) workplace management, and (f) policy and regulations. The findings from the study could be used by front-line military supervisors to become proactive leaders that use practical, sustainable practices effectively to manage energy conservation in military installations. The implications for positive social change include the potential to reduce energy usage in the Federal government.
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Solh, Joukhah Zahra. "Operation of HVDC converters for transformer inrush current reduction." Doctoral thesis, Universitat Politècnica de Catalunya, 2017. http://hdl.handle.net/10803/461569.
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The present PhD thesis deals with transformer inrush current in offshore grids including offshore wind farms and High Voltage Direct Current (HVDC) transmission systems. The inrush phenomenon during transformers energization or recovery after the fault clearance is one of important concerns in offshore systems which can threaten the security and reliability of the HVDC grid operation as well as the wind farms function. Hence, the behaviour of wind turbines,Voltage Source Converters (VSC) and transformer under the normal operation and the inrush transient mode is analyzed.
For inrush current reduction in the procedure of the offshore wind farms start-up and integration into the onshore AC grid, a technique based on Voltage Ramping Strategy (VRS) is proposed and its performance is compared with the operation of system without consideration of this approach. The new methodology which is simple, cost-effective ensures minimization of transformer inrush current in the offshore systems and the enhancement of power quality and the reliability of grid under the transformer energizing condition. The mentioned method can develop much lower inrush currents according to the slower voltage ramp slopes.
Concerning the recovery inrush current, the operation of the offshore grid especially transformers is analyzed under the fault and the system restoration modes.The recovery inrush transient of transformers can cause tripping the HVDC and wind farms converters as well as disturbing the HVDC power transmission. A voltage control design based on VRS is proposed in HVDC converter to recover ali the transformers in offshore grid with lower inrush currents.The control system proposed can assure the correct performance of the converters in HVDC system and in wind farm and also the robust stability of the offshore grid.Esta tesis doctoral estudia las corrientes de energización de transformadores de parques eólicos marinos con aerogeneradores con convertidores en fuente de tensión (VSC) de plena potencia conectados a través de una conexión de Alta Tensión en Corriente Continua (HVDC). Las corrientes de energización pueden disminuir la fiabilidad de la transmisión eléctrica debido a disparos intempestivos de las protecciones durante la puesta en marcha o recuperación de una falta. Para la mitigación de las corrientes de energización durante la puesta en marcha del parque esta tesis propone una nueva estrategia basada en incrementar la tensión aplicada por el convertidor del parque eólico en forma de rampa (VRS). Este método persigue energizar el parque eólico con el menor coste y máxima fiabilidad. La tesis analiza diferentes escenarios y diferentes rampas. Otro momento en que las corrientes de energización pueden dar lugar a un disparo intempestivo de las protecciones es durante la recuperación de una falta en la red de alterna del parque eólico marino. Esta tesis extiende la estrategia VRS, utilizada durante la puesta en marcha del convertidor del parque, para los escenarios de recuperación de una falta.
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Li, Xin. "Reduction of wind power curtailment in power system operation." Thesis, University of Strathclyde, 2015. http://oleg.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=25925.
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Clean, affordable energy is essential for continued growth of the economy in a country. Almost every country's laws and policies put in place in the last decade encourage energy suppliers to incorporate large amounts of renewable generation (wind and solar). This has changed the traditional mix of (3)4z(Bfuels(3)4y (Bused for energy generation. Integrating these resources into a reliable and affordable power system will require an unprecedented level of cooperative action within the electric industry, related utilities and the state. Power grid has existing flexibility in the system to cost-effectively integrate wind resources but, as operated today, more can be done. Integration involves managing the variability (the range of expected electricity generation output) and uncertainty (when and how much that generation will change during the day) of energy resources. Wind is one kind of free energy and this (3)4z(Bmust-take(3)4y (Bwind power generation is integrated into th e system operation. In this thesis, the impacts on the combined conventional generators, the transmission lines and the operation costs will be examined under different system operation conditions (constrained and unconstrained) with increasing wind power penetration. The firm scheduled bilateral contract from the conventional generation can cause transmission congestion and free wind power cannot be integrated into the power system operation sufficiently. This thesis proposes a combined pool/bilateral trade model to cooperate with wind power output fluctuations to increase the utilisation of wind farm which are currently constrained by the transmission networks. The one-step optimal power flow model dispatches the pool in combination with the curtailed part of fixed bilateral contracts from conventional generators. The aim is integrating maximum wind energy in the power system while minimizing costs. A dynamic wind turbine model is used to identify the impacts of integrating wind power into system operation; the Weibull Distribution Function is used to analyze the problem of wind distribution; and the Monte Carlo Simulation (MCS) method is used to simulate the output of wind power generation. The proposed combined pool/bilateral trade model is applied to the modified IEEE-9 bus system for verification and validation. Following this, the analysis on IEEE-30 bus system is the comparison studies with the proposed one-step combined pool/bilateral trade model under different bidding prices. Two case studies with different market strategies through the proposed method are introduced, with different volume values of the firm bilateral contracts and the different payments for the curtailment bids. The simulation results show the relative level of pool versus bilateral trading and these influences on the performance in terms of individual power generation levels and costs. The well-proven software tools MATLAB and MATPOWER support the study.
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Emmert, Terence G. (Terence Gordon) 1966. "Process time variation reduction in a microprocessor burn-in operation." Thesis, Massachusetts Institute of Technology, 2001. http://hdl.handle.net/1721.1/84229.
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Thesis (S.M.)--Massachusetts Institute of Technology, Sloan School of Management; and, (S.M.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2001.Includes bibliographical references (leaves 96-97).
by Terence G. Emmert.
S.M.
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Henry, Michael Brewer. "Power Reduction of Digital Signal Processing Systems using Subthreshold Operation." Thesis, Virginia Tech, 2009. http://hdl.handle.net/10919/33691.
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Over the past couple decades, the capabilities of battery-powered electronics has expanded dramatically. What started out as large bulky 2-way radios, wristwatches, and simple pacemakers, has evolved into pocket sized smart-phones, digital cameras, person digital assistants, and implantable biomedical chips that can restore hearing and prevent heart attacks. With this increase in complexity comes an increase in the amount of processing, which runs on a limited energy source such as a battery or scavenged energy. It is therefore desirable to make the hardware as energy efficient as possible. Many battery-powered systems require digital signal processing, which often makes up a large portion of the total energy consumption. The digital signal processing of a battery-powered system is therefore a good target for power reduction techniques. One method of reducing the power consumption of digital signal processing is to operate the circuit in the subthreshold region, where the supply voltage is lower than the threshold voltage of the transistors. Subthreshold operation greatly reduces the power and energy consumption, but also decreases the maximum operating frequency. Many digital signal processing applications have real-time throughput requirements, so various architectural level techniques, such as pipelining and parallelism, must be used in order to achieve the required performance.
This thesis investigates the use of parallelization and subthreshold operation to lower the power consumption of digital signal processing applications, while still meeting throughput requirements. Using an off the shelf fast fourier transform architecture, it will be shown that through parallelization and subthreshold operation, a 70 \% reduction in power consumption can be achieved, all while matching the performance of a nominal voltage single core architecture. Even better results can be obtained when an architecture is specifically designed for subthreshold operation. A novel Discrete Wavelet Transform architecture is presented that is designed to eliminate the need for memory banks, and a power reduction of 26x is achieved compared to a reference nominal voltage architecture that uses memory banks. Issues such as serial to parallel data distribution, dynamic throughput scaling, and memory usage are also explored in this thesis. Finally, voltage scaling greatly increases the design space, so power and timing analysis can be very slow due long SPICE simulation times. A simulation framework is presented that can characterize subthreshold circuits accurately using only fast gate level design automation tools.
Master of Science
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Leimalm, Ulrika. "Pellet reduction properties under different blast furnace operating conditions." Licentiate thesis, Luleå : Luleå tekniska universitet/Tillämpad kemi och geovetenskapProcessmetallurgi, 2006. http://epubl.ltu.se/1402-1757/2006/67/LTU-LIC-0667-SE.pdf.
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Ng, Kwai-sang Sam. "The use of prior information for the reduction of operation anxiety." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1998. http://hub.hku.hk/bib/B29726499.
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Zhang, Fan. "Integrated electromechanical wind turbine control for power system operation and load reduction." Thesis, University of Strathclyde, 2013. http://oleg.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=22650.
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With the penetration level of wind power in electric power networks increasing rapidly all over the world, modern wind turbines are challenged to provide the same grid services as conventional synchronous power plants. The dynamic interaction between wind turbines and grid has to be assessed first before replacing large amount of conventional power plants by wind power. Over the last few years many power system operators have revised their grid codes and established more demanding requirements for wind power connection. In the past, when wind turbines were small, they were allowed to simply disconnect during a grid fault/disturbance. However, as wind turbine size has increased considerably, their fault ride-through capability has to be improved if the penetration of wind power is to be further increased. Wind turbine design and control need to be improved to optimize the compatibility of wind power and the grid. Among the various requirements that wind turbines have to meet, fault ride-through is of great importance and a very challenging one. Grid faults cause transients not only in the electrical system, but also in the wind turbine mechanical system. The dynamic performance of wind turbines is determined by both mechanical and electrical systems. From the mechanical point of view, the grid disturbance adds extra loads on wind turbine components. Severe grid faults may even lead to wind turbine emergency shut-down. From the electrical point of view, wind farms may lose power generation during a grid fault, which deteriorates the fault impact and slows down the fault recovery. Advanced control and active damping is required to improve wind turbine operation and assist it to remain connected during a grid fault. The novelty of this research is the study of the interaction between mechanical and electrical systems of the wind turbine. The detailed modelling of both the wind turbine mechanical and electrical dynamics not only helps to identify possible problems that wind turbines encounter during grid faults, but also allows adopting a combined approach to design the wind turbine controller. This thesis aims at improving the wind turbine fault ride-through capability and the ability of wind turbine to provide network support during grid disturbances. The main contents are as follows: The detailed model of wind turbine and grid including wind turbine mechanical model, wind turbine controller, synchronous and induction generator model, doubly fed induction generator (DFIG) controller and a generic network model are presented; A wind turbine fault ride-through strategy considering structural loads alleviation is proposed; A controller for asymmetrical fault ride-through of DFIG wind turbines is presented; The effect of having Power System Stabilizer (PSS) on wind turbine is investigated. A multi-band PSS controller for DFIG wind turbine is demonstrated.
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Lee, Tae Jung. "Characterisation of anode supported microtubular SOFC process on pure methane reduction and operation." Thesis, University of Birmingham, 2010. http://etheses.bham.ac.uk//id/eprint/592/.
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The optimisations of reduction and operation of Ni-YSZ anode supported micro tubular cells on pure methane were studied. A major problem of SOFCs is nickel anode performance on methane and higher hydrocarbons. The aim of this work was to study the effect of reduction and operation of anode-supported microtubular SOFCs using methane as both reductant and fuel. The results were compared to those from optimised operation using hydrogen. To measure mechanical strength, the three point bending test was employed. Temperature programmed oxidation (TPO) results were investigated to measure the carbon deposition on the anode in order to assess potential damage to the cermet catalyst. Also field emission scanning electron microscope (FE-SEM) and Energy-Dispersive X-ray spectroscopy EDS results were analysed on the anode surface.
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Huston, Todd W. (Todd Wendell). "Production system design and cycle time reduction in a fuel cell manufacturing operation." Thesis, Massachusetts Institute of Technology, 1996. http://hdl.handle.net/1721.1/10910.
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Thesis (M.S.)--Massachusetts Institute of Technology, Sloan School of Management, 1996, and Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 1996.Includes bibliographical references (leaves 104-105).
by Todd W. Huston.
M.S.
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Sanchez, Rene G. "Construction and operation of an in-pile loop for PWR dose reduction experiments." Thesis, Massachusetts Institute of Technology, 1990. http://hdl.handle.net/1721.1/13669.
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Boone, Gary Noel. "Extreme dimensionality reduction for text learning : cluster-generated feature spaces." Diss., Georgia Institute of Technology, 2000. http://hdl.handle.net/1853/8139.
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Oosthoek, Peter B. "A DATABASE SYSTEM CONCEPT TO SUPPORT FLIGHT TEST - MEASUREMENT SYSTEM DESIGN AND OPERATION." International Foundation for Telemetering, 1993. http://hdl.handle.net/10150/608879.
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International Telemetering Conference Proceedings / October 25-28, 1993 / Riviera Hotel and Convention Center, Las Vegas, NevadaInformation management is of essential importance during design and operation of flight test measurement systems to be used for aircraft airworthiness certification. The reliability of the data generated by the realtime- and post-processing processes is heavily dependent on the reliability of all provided information about the used flight test measurement system. Databases are well fitted to the task of information management. They need however additional application software to store, manage and retrieve the measurement system configuration data in a specified way to support all persons and aircraft- and ground based systems that are involved in the design and operation of flight test measurement systems. At the Dutch National Aerospace Laboratory (NLR) a "Measurementsystem Configuration DataBase" (MCDB) is being developed under contract with the Netherlands Agency for Aerospace Programs (NIVR) and in cooperation with Fokker to provide the required information management. This paper addresses the functional and operational requirements to the MCDB, its data-contents and computer configuration and a description of its intended way of operation.
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Ozkan, Tulay. "Leakage Control By Optimal Valve Operation." Phd thesis, METU, 2008. http://etd.lib.metu.edu.tr/upload/3/12609419/index.pdf.
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The main function of a water distribution system is to supply water in sufficient quantity at appropriate pressure with an acceptable quality and as economically as possible. Water leakage in distribution networks may account from 5% to 50% and even larger of the total water delivered. The amount of leakage in a network is directly related to system service pressure. Therefore, reductions in high service pressures will result in considerable reductions in leakage. A methodology for leakage reduction has been presented in context of a developed computer program, LEAKSOL with two sub-programs. The first code, CODE I, provides solution by using optimization techniques with defined pressure-leakage and pressure-demand relations in order to find optimal flow control valve settings minimizing water leakage. The second one, CODE II, makes hydraulic analysis of the network in order to solve the system and to compute the amount of leakage and the amount of water consumed, by using different combinations of isolation valves generated according to the number of valves given and employing the relationships among pressure, leakage and consumption. Computer program application was performed for different scenarios in a sample network previously used in literature and also in N8-3 pressure zone of Ankara Municipal Water Supply System. Leakage reduction up to 10 % has been achieved in N8-3 pressure zone for eight valves located at the entrances of sub-zones, depending on the defined pressure-leakage relationship.