Dissertations / Theses: 'Electrical Engineering'

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Uudelepp, Oscar, Ellen Nordén, and Douglas Lowén. "Electric Bike : Independent Project in Electrical Engineering." Thesis, Uppsala universitet, Institutionen för teknikvetenskaper, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-353617.

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A group project has been made in which the goal was to build an electric bike. The main focus of the project was to build the surrounding control system of a BLDC motor. A complete BLDC hub motor was purchased. The wheel managed to spin forward but it was never implemented on a bike due to time constraints. This was a rewarding and educational project that can be replicated or improved for future students.

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Tandon, Nina. "Biomimetic electrical stimulation for cardiac tissue engineering." Thesis, Massachusetts Institute of Technology, 2006. http://hdl.handle.net/1721.1/38323.

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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2006.
Includes bibliographical references (leaves 66-69).
A major challenge of tissue engineering is directing cells to establish the physiological structure and function of the tissue being replaced. Electrical stimulation has been used to induce synchronous contractions of cultured cardiac constructs. The hypothesis adopted for this study is that functional cardiac constructs can be engineered by "mimicking" the conditions present during cardiac development, and in particular, electrical stimulation using supra-threshold signals. For this Master's Thesis research, I have compared the material properties and charge-transfer characteristics at the electrode-electrolyte interface of various biocompatible materials, including carbon, stainless steel, titanium and titanium nitride, for use as electrodes in a biomimetic system for cardiac tissue engineering. I have also designed and implemented an electrical stimulator which is capable of modulating several important parameters of electrical stimulation, including stimulus amplitude and frequency.
(cont.) In addition, I have built an experimental setup incorporating this electrical stimulator and used it for experiments with C2C12 mouse myoblast cells and neonatal rat cardiomyocytes. Lastly, I have analyzed cell morphology as well as functional performance of engineered tissue by assessing excitation thresholds and maximum capture rates.
by Nina Tandon.
S.M.

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Björklund, Marcus, and Eric Fjärstedt. "Active Stabilizer : Independent Project in Electrical Engineering." Thesis, Uppsala universitet, Institutionen för teknikvetenskaper, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-324765.

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Khrapach, Ivan. "Engineering the electrical properties of graphene materials." Thesis, University of Exeter, 2012. http://hdl.handle.net/10871/8168.

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In this thesis the properties of graphene and its few-layers are engineered to make them highly conductive. Two different approaches were implemented to achieve this goal. One approach was to increase the concentration of charge carriers by intercalation of acceptor FeCl3 molecules between graphene planes. This resulted in a highly conductive yet transparent material which can be useful for applications. Another approach was to increase the mobility of carriers by means of removing surface contamination in the current annealing process. Optimal annealing parameters were found and a reproducible cleaning method was suggested.

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Shi, Bowen. "High performance permanent magnet electrical machine for electrical vehicle applications." Thesis, University of Nottingham, 2018. http://eprints.nottingham.ac.uk/52331/.

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For electrical vehicle system, torque density, power density, output performance, high-speed range, reliability and cost are of the most importance. This means that the designing and manufacturing of high-performance traction system must be employed, regarding electrical machine, drive and battery. In this work, the main target is to propose and investigate methods for improving the designing of the electrical machine on EVs traction system. Permanent Magnet Synchronous Machine (PMSM) with the advantage on high power density, high efficiency and excellent power factor has been widely used in EVs applications, especially the high saliency type motor called Interior Permanent Magnet Machine (IPM). The use of performance map is a valuable evaluation tool for EVs machines, in terms of torque-speed ability and efficiency presentation. A FEM based performance mapping tool is designed and presented to improve such evaluation abilities, with motor control method evolved, advanced losses evaluation and optimal running time. With the evaluation tool secured, the design of an IPM traction motor is employed with prototype and experimental test, to deliver high power density, good torque performance, low harmonic content and wide speed capability. To ensure the smooth running of EVs, novel skewing method for motor, called modular skewing, is then introduced to archive optimal torque ripple minimization on IPM, rather than optimizing the cogging torque. The technique has been developed through vector redistribution algorithm and testified by 2D FEM modelling. Basing on the new designed IPM motor, a novel motor structure, named End-winding Flux Motor (EWFM), is invented, whose structure can be embedded to most type of conventional PMSM end-winding side for the purpose of end-winding utilization, power density increases and thermal improvements. In the end, the 3D FEM and experimental tests validate the concept of EWFM.

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Larsson, Erik, and Niklas Kron. "Independent project in electrical engineering : Magnetic hand timepiece." Thesis, Uppsala universitet, Institutionen för teknikvetenskaper, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-325637.

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Briggs, Jaime C. "Web-based testing tools for Electrical Engineering courses." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2001. http://handle.dtic.mil/100.2/ADA397129.

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Thesis (M.S. in Electrical Engineering and M.S. in Computer Science) Naval Postgraduate School, Sept. 2001.
Thesis advisors: Crosto. Roberto ; Wu, Thomas. "September 2001." Includes bibliographical references (p. 113-114). Also available online.

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Looe, Hui Mun. "Electromagnetic modelling and analysis of electrical engineering systems." Thesis, University of Liverpool, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.400238.

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Patel, Dipali Dhanji. "Design of experiment on electrical engineering design representations." Thesis, Montana State University, 2004. http://etd.lib.montana.edu/etd/2004/patel/PatelD0805.pdf.

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Bernstein, Joseph Barry. "Electrical characterization of polymeric insulation by electrically stimulated acoustic wave measurements." Thesis, Massachusetts Institute of Technology, 1990. http://hdl.handle.net/1721.1/54340.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1990.
Includes bibliographical references (leaves 207-211).
by Joseph Barry Bernstein.
Ph.D.

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Carnes, Mark T. "Conceptual understanding of threshold concepts of electrical phenomena| Mental models of senior undergraduates in electrical engineering." Thesis, Purdue University, 2017. http://pqdtopen.proquest.com/#viewpdf?dispub=10244516.

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Every field of study has a set of domain-specific concepts that anyone who desires to work in that field must know and understand. Most students who pursue university degrees in engineering trust that their education is designed to provide them with this knowledge. But does it? In electrical engineering (EE), conceptual understanding of electrical phenomena has rarely been addressed. Even though the presumed goal of instructors and students alike is to learn the concepts of electrical phenomena well enough to be able to use the concepts to design useful things, it is difficult to determine whether this goal is being achieved. The purpose of this study was to develop reasonable representations of the mental models used by senior EE students as they thought about and worked with electrical phenomena. Focusing on students’ mental models of threshold concepts in electrical phenomena can thus increase knowledge of students’ conceptual understanding, which can contribute to systematic research into pedagogical and assessment methods in this area of study, which forms one of the most basic and fundamental areas of knowledge needed by EE students.

Thus, the research question addressed by this study was:

What do senior EE students’ mental models of the fundamental electrical phenomena of voltage, current, and the relationship between them look like?

The theory of mental models claims that everyone organizes their understanding of the way the world works by constructing models in the mind by which they both explain phenomena that they observe, and make predictions about what is likely to occur in a given situation.

To observe the students’ mental models in operation, semi-structured interviews were used to engage the participants in a conversation concerning their knowledge and experience in applying electrical ideas. Using discourse analysis, a representation of each student’s mental model was created, consisting of a concept map and a short narrative. While the models were all different, analysis of them as a group led to the emergence of five dominant themes, or ways of thinking.

The findings of this study have implications for the course of study that these students are engaged in. How effective has it been in developing the conceptual understanding that they will need after they graduate? Knowledge of the outcomes of a course of study: the conceptual understanding of these students, the misconceptions present in their models, and the dominant themes that drive their models, can inform ongoing efforts in curriculum development.

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South, G. "A technique for measuring the electrical impedance of mechanical joints in electrically conductive structures." Thesis, University of Central Lancashire, 1992. http://clok.uclan.ac.uk/20064/.

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The impedance of a circular coil placed above a conducting surface is calculated using three mathematical models. The first considers the interaction of the test coil with a uniform, homogeneous and electrically thick conducting sheet. The model quantifies the interaction of the coil and the surface by calculating the field around the coil in the frequency domain. The sheet is included by using reflection coefficients, calculated from defined physical properties, to modify the field components surrounding the coil. Cylindrical symmetry is used to reduce the problem to two dimensions. The second model is a finite difference solution in the frequency domain of the differential equation describing the magnetic vector potential. Cylindrical symmetry is used to reduce the problem to two dimensions. An approximation allowing a mechanical joint of finite physical dimensions to be included is described. The third model is a finite difference, time domain solution of the differential form of the field equations. This is a complete three dimensional analysis of the problem, including the effect of fasteners and sealants. An algorithm allowing the inclusion of materials with anisotropic electrical conductivity is described. Fourier analysis is used to transform the time domain results into the frequency domain. The results calculated from the three models are compared with practical measurements. Two instruments are constructed and practically evaluated. The first is suitable for frequencies up to 50kHz. It is based upon two test coils in a bridge arrangement and the effect of the joint is measured in terms of the out-of-balance bridge voltage. The second instrument is based upon the effect of the joint of interest upon the resonant frequency of a test coil, measured using a modified Q meter circuit. Frequencies up to 70MHz have been considered.

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Tam, Wvi Huat. "Web-based teaching and learning of Electrical Engineering Courses." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2001. http://handle.dtic.mil/100.2/ADA390419.

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Thesis (M.S. in Electrical Engineering) Naval Postgraduate School, March 2001.
Thesis advisor(s): Butler, Jon T. "March 2001." Includes bibliographical references (p. 103). Also available in print.

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Orgunmat, Kaan. "Heatapp - Remote TemperatureController Project : Degree Project in Electrical Engineering." Thesis, Blekinge Tekniska Högskola, Avdelningen för elektroteknik, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-866.

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The project is a part of series of hardware and software challenges merging in one. It is fundamentally an application to monitor the temperature changes and get notications based on those changes. Also through this application an electrical device that is connected to an outlet will be controlled remotely. It is a feature for the users that do not have access to certain type of devices and want to turn on/off them.This project is built by using a digital remote controller and an outlet (REMOTE CONTROLLEDOUTLETS 310000) that a potential heating system is connected to. The remote controller is controlled via Arduino. On Arduino there are two relays (PRMA2A12B) that turns the remote control on and off based on the input signal that is sent. There is also a temperature sensor connected to the Arduino. The readings from the temperature sensor are sent to a web server and stored there in order to track the changes. On the web interface, other than reading and tracking temperature changes, it is possible to turn on/off an outlet with an integrated button.

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Sellergren, Albin, Tobias Andersson, and Jonathan Toft. "Signal processing through electroencephalography : Independent project in electrical engineering." Thesis, Uppsala universitet, Elektricitetslära, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-298771.

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This report is about a project where electroencephalography (EEG) wasused to control a two player game. The signals from the EEG-electrodeswere amplified, filtered and processed. Then the signals from the playerswere compared and an algorithm decided what would happen in the gamedepending on which signal was largest. The controls and the gaming mechanismworked as intended, however it was not possible to gather a signal fromthe brain with the method used in this project. So ultimately the goal wasnot reached.
electroencephalography, EEG

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Akaslan, Dursun. "A model for supporting electrical engineering with e-learning." Thesis, University of Leicester, 2014. http://hdl.handle.net/2381/29066.

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The overall goal of this research work was developing and evaluating a model for supporting electrical engineering with e-learning. The model development was based on the survey data collected from representative teachers and students in Turkey whereas the model evaluation was conducted in the relevant HEIs in Turkey and the United Kingdom. To develop the model, the study investigated the attitudes of representative key stakeholders towards e-learning in Turkey by administrating questionnaires and interviews with teachers and students. Then the responses of the teachers and students were compared. Based on the results, I proposed a model with a multi-dimensional approach to e-learning: (1) self-directed learning by studying e-book, (2) self-assessment by solving e-exercises, (3) teacher-directed learning by attending classroom sessions as an integral part of the blended learning (4) teacher-assessment by solving e-exercises, (5) computer-directed learning by playing e-games and (6) computer-assessment by solving e-exercises. To evaluate the applicability of the model in different conditions, a case-control study was conducted to determine whether the model had the intended effect on the participating students in HEIs in Turkey and the United Kingdom. As the result of the case-control study, the effects of e-learning, blended learning and traditional learning were verified. However, there were significant differences among the groups. The overall scores indicated that e-learning and blended learning was more effective as compared to the traditional learning. The results of our study indicated that the knowledge increase in e-learners seemed to be gradual because they tended to study daily by completing each activity on time. However, the traditional learners did not have the same pattern because they usually did not read the core text and did not solve e-exercise regularly before the classroom sessions. The results of pre-placement, post-placement tests and middle tests also justified these assumptions.

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Balavendran, Joseph Rani Deepika. "Gamification to Solve a Mapping Problem in Electrical Engineering." Thesis, University of North Texas, 2020. https://digital.library.unt.edu/ark:/67531/metadc1703330/.

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Coarse-Grained Reconfigurable Architectures (CGRAs) are promising in developing high performance low-power portable applications. In this research, we crowdsource a mapping problem using gamification to harnass human intelligence. A scientific puzzle game, Untangled, was developed to solve a mapping problem by encapsulating architectural characteristics. The primary motive of this research is to draw insights from the mapping solutions of players who possess innate abilities like decision-making, creative problem-solving, recognizing patterns, and learning from experience. In this dissertation, an extensive analysis was conducted to investigate how players' computational skills help to solve an open-ended problem with different constraints. From this analysis, we discovered a few common strategies among players, and subsequently, a library of dictionaries containing identified patterns from players' solutions was developed. The findings help to propose a better version of the game that incorporates these techniques recognized from the experience of players. In the future, an updated version of the game that can be developed may help low-performance players to provide better solutions for a mapping problem. Eventually, these solutions may help to develop efficient mapping algorithms, In addition, this research can be an exemplar for future researchers who want to crowdsource such electrical engineering problems and this approach can also be applied to other domains.

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Chien, Yu-Chien. "Electrical Aspects of Impinging Flames." Thesis, University of California, Irvine, 2015. http://pqdtopen.proquest.com/#viewpdf?dispub=3682710.

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This dissertation examines the use of electric fields as one mechanism for controlling combustion as flames are partially extinguished when impinging on nearby surfaces. Electrical aspects of flames, specifically, the production of chemi-ions in hydrocarbon flames and the use of convective flows driven by these ions, have been investigated in a wide range of applications in prior work but despite this fairly comprehensive effort to study electrical aspects of combustion, relatively little research has focused on electrical phenomena near flame extinguishment, nor for flames near impingement surfaces. Electrical impinging flames have complex properties under global influences of ion-driven winds and flow field disturbances from the impingement surface. Challenges of measurements when an electric field is applied in the system have limited an understanding of changes to the flame behavior and species concentrations caused by the field. This research initially characterizes the ability of high voltage power supplies to respond on sufficiently short time scales to permit real time electrical flame actuation. The study then characterizes the influence of an electric field on the impinging flame shape, ion current and flow field of the thermal plume associated with the flame. The more significant further examinations can be separated into two parts: 1) the potential for using electric fields to control the release of carbon monoxide (CO) from surface-impinging flames, and 2) an investigation of controlling electrically the heat transfer to a plate on which the flame impinges. Carbon monoxide (CO) results from the incomplete oxidation of hydrocarbon fuels and, while CO can be desirable in some syngas processes, it is usually a dangerous emission from forest fires, gas heaters, gas stoves, or furnaces where insufficient oxygen in the core reaction does not fully oxidize the fuel to carbon dioxide and water. Determining how carbon monoxide is released and how heat transfer from the flame to the plate can be controlled using the electric field are the two main goals of this research. Multiple diagnostic techniques are employed such as OH chemiluminescence to identify the reaction zone, OH PLIF to characterize the location of this radical species, CO released from the flame, IR imaging and OH PLIF thermometry to understand the surface and gas temperature distribution, respectively. The principal finding is that carbon monoxide release from an impinging diffusion flame results from the escape of carbon monoxide created on the fuel side of the flame along the boundary layer near the surface where it avoids oxidation by OH, which sits to the air side of the reaction sheet interface. In addition, the plate proximity to the flame has a stronger influence on the emission of toxic carbon monoxide than does the electric field strength. There is, however, a narrow region of burner to surface distance where the electric field is most effective. The results also show that heat transfer can be spatially concentrated effectively using an electric field driven ion wind, particularly at some burner to surface distances.

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Beardsmore-Rust, Sam Thomas. "Remote applications of electric potential sensors in electrically unshielded environments." Thesis, University of Sussex, 2010. http://sro.sussex.ac.uk/id/eprint/2407/.

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The electric potential sensor is a novel, ultra high impedance sensor, previously developed at the University of Sussex. These sensors have been applied to a range of applications, including electrophysiology, non destructive testing of composite materials and novel nuclear magnetic resonance NMR probes. Some of these measurements can be made in a strongly coupled (≥100pF) mode, where the coupling capacitance is reasonably large and well dened, and ambient noise is therefore less problematic. However for many applications, there exists a requirement for this coupling to be much weaker. This weak and poorly dened coupling creates substantial problems with ambient noise often causing sensors to saturate and become unusable. In the past, therefore, these measurements have all been made inside electrically screened rooms and enclosures. The work discussed in this thesis explores the possibility of operating these sensors outside of electrically screened environments. A number of techniques for resilience against noise are explored and experiments to fully analyse and characterise the performance of the sensors are discussed. As a result of this work, further results are then shown for a number of experiments carried out in a busy lab environment, in the presence of noise sources, and with little or minimal screening used. In this case, data is shown for the collection of remote cardiac and respiratory data, imaging of the spatial distribution of charge on insulating materials, detecting electric eld disturbances for movement sensing and early results for a microscopic XY scanning application.

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Ahmadi, Teshnizi Amir Pouya, Marcus Hellström, Tom Bärnheim, and Hassan Soltani. "IoT Air Quality Sensor Array : Master's Programme in Electrical Engineering." Thesis, Uppsala universitet, Institutionen för elektroteknik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-448142.

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Solander, Araúz Ingemar. "The Effect of Harmonics on the Electrical Grid due to Electric Vehicle Chargers." Thesis, Uppsala universitet, Institutionen för elektroteknik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-428756.

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In this thesis the effect of harmonics on the electrical grid from electric car chargers, specifically the effect on distribution transformers, is analyzed. The study was performed on the electrical grid of two areas provided by the electrical company Dala Energi. Electric car chargers are added to each customer connected to the electrical grid in both areas to examine the effects of harmonics on the distribution transformers. A model of the electrical grid of each area was recreated and simulated with the open source program OpenDSS. The effects of the added harmonic load on the electrical grid was evaluated in a range from 10% to a 100% of the consumers connected to the grid. The results of this study show an increase in losses due to harmonic distortion. However, the losses are less significant when the added electric car charger load is distributed between all three phases of the grid compared to one phase. All the added harmonics, except the 9th harmonic, maintain acceptable levels set by The Swedish Energy Market Inspectorate. The impact of the 9th harmonic can be reduced by installing filters. The main conclusion of this thesis is that to reduce the effects of harmonic on the grid the harmonic load should be distributed on all three phases. Also scheduling the charging time of the cars can be implemented to further even out the load variations on the electrical grid.

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Potgieter, L. "Circuit tutor : a computer-aided learning package for electrical engineering." Master's thesis, University of Cape Town, 1989. http://hdl.handle.net/11427/23322.

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The development of Circuit Tutor, the subject of this dissertation, resulted from a conviction that computers can further enrich the Electronic Engineering curriculum. After an investigation into the different roles of the computer in education the use of modelling and simulation was selected as an effective Computer Aided Learning method. It was realised that the development of any non-trivial simulation program is however not an easy task. The programmer must not only model the circuit behaviour, but also write the man-machine interface (MMI). The main goal of Circuit Tutor was to provide a ready-made simulation environment which makes effective use of the graphics capabilities of the microcomputer for the simulation of a whole class of electrical circuit simulations. To facilitate rapid prototyping the installer is provided with: (1) a man-machine interface which provides the user with a graph, 3 meters, a circuit diagram of the circuit, a menu facility, windows to view circuit parameters and outputs: (2) a program scheduler; (3) a library of maths functions, including Gauss-Jordan elimination of complex matrices; and (4) Circuit Draw: a utility to draw a circuit diagram. Particular emphasis was placed on the design of the user's interface. It has been possible to restrict the effort to link in a new circuit model to 3 modifications to the man-machine interface (MMI) part of the program. Present software and MMI design were investigated. Circuit Tutor and Circuit Draw were developed using modular software design techniques. A modular design chart similar to that proposed by Wiener (1984) was found to be useful during the design stages of both Circuit Tutor and Circuit Draw. Available computer languages for the IBM PC were evaluated and Turbo Pascal selected, as it offered most of the features necessary for the implementation of a modern, modular software design. Four circuits were implemented to serve as examples. The documentation was structured in a manner appropriate to a software project: Part 1 gives an introduction to computers in education and provides the rationale for the use of simulation. A brief overview of Circuit Tutor and Circuit Draw is presented. Part 2 contains the User's Reference Manual for Circuit Tutor and the Circuit Draw Utility. Part 3 contains the Designer's Reference Manual for Circuit Tutor and the Circuit Draw Utility.

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Jia, Chen. "Higher-level learning in an electrical engineering linear systems course." Diss., Kansas State University, 2015. http://hdl.handle.net/2097/19171.

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Doctor of Philosophy
Electrical and Computer Engineering
Steven Warren
Linear Systems (a.k.a., Signals and Systems) is an important class in an Electrical Engineering curriculum. A clear understanding of the topics in this course relies on a well-developed notion of lower-level mathematical constructs and procedures, including the roles these procedures play in system analysis. Students with an inadequate math foundation regularly struggle in this class, as they are typically able to perform sequences of the underlying calculations but cannot piece together the higher-level, conceptual relationships that drive these procedures. This dissertation describes an investigation to assess and improve students’ higher-level understanding of Linear Systems concepts. The focus is on the topics of (a) time-domain, linear time-invariant (LTI) system response visualization and (b) Fourier series conceptual understanding, including trigonometric Fourier series (TFS), compact trigonometric Fourier series (CTFS), and exponential Fourier series (EFS). Support data, including exam and online homework data, were collected since 2004 from students enrolled in ECE 512 - Linear Systems at Kansas State University. To assist with LTI response visualization, two online homework modules, Zero Input Response and Unit Impulse Response, were updated with enhanced plots of signal responses and placed in use starting with the Fall 2009 semester. To identify students’ conceptual weaknesses related to Fourier series and to help them achieve a better understanding of Fourier series concepts, teaching-learning interviews were applied between Spring 2010 and Fall 2012. A new concept-based online homework module was also introduced in Spring 2011. Selected final exam problems from 2007 to 2012 were analyzed, and these data were supplemented with detailed mid-term and final exam data from 77 students enrolled in the Spring 2010 and Spring 2011 semesters. In order to address these conceptual learning issues, two frameworks were applied: Bloom’s Taxonomy and APOS theory. The teaching-learning interviews and online module updates appeared to be effective treatments in terms of increasing students’ higher-level understanding. Scores on both conceptual exam questions and more traditional Fourier series exam questions were improved relative to scores received by students that did not receive those treatments.

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Glendinning, D. Duncan R. Carleton University Dissertation Engineering Electrical. "A personal workstation based CAD environment for electrical engineering education." Ottawa, 1985.

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Al, Kzair Christian, Altin Januzi, and Andreas Blom. "Understanding the fundamentals of CPU architecture : Bachelor project in Electrical engineering." Thesis, Uppsala universitet, Institutionen för teknikvetenskaper, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-353427.

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Understanding how a computer or rather a CPU works can be a bit tricky and hard to understand. We live today in a society full of computers and there are many who do not understand how a CPU works. This project is aimed to understand how a CPU works and the architecture behind it. For this it is demonstrated the fundamental theory behind it but also a practical computer that has been built from scratch. This computer can demonstrate the theory behind how the CPU works and also how it communicates. This computer is 8-bit which has it limitations but can show the fundamental theory behind how computers work.

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Lewis, Racheida Sharde. "The Influences of First-Year Engineering Matriculation Structures on Electrical and Computer Engineering Students' Self-Efficacy." Diss., Virginia Tech, 2019. http://hdl.handle.net/10919/103325.

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While first-year engineering (FYE) programs have grown dramatically over the last 30 years, they take a variety of different structures. However, few if any, researchers and FYE program developers has considered how program structure, and specifically matriculation, impacts retention – an issue that continues to be of concern as we seek to grown the national engineering workforce. Low retention rates combined with lack of diversity becomes even more acute when considering the field of Electrical and Computer Engineering (ECE) which ranks as one of the least diverse engineering disciplines. One factor that has been shown to support retention is self-efficacy or individuals' beliefs in their ability to succeed. Therefore, to help address the retention issues in ECE, this dissertation explores the programmatic influence of first-year engineering matriculation structures on self-efficacy development in electrical and computer engineering students. In particular, it compares declared engineering (DE) programs, which admit students to a specific engineering field, to general engineering (GE) programs, in which students are admitted to engineering but do not select a specific engineering field until after their first year. Using qualitative and quantitative methodologies, this dissertation presents three manuscripts: 1) a quantitative secondary analysis comparing competency beliefs in a GE program and a quasi- DE first-year engineering program for ECE students; 2) a qualitative secondary analysis of self-efficacy development in a DE first-year program; and 3) a qualitative analysis exploring similarities and differences in self-efficacy development in EE students at two universities, one with a DE program and one with a GE program. The exploratory studies resulted in findings that demonstrate strong similarities in self-efficacy development in students from the DE and GE programs. Those differences that did emerge are largely attributed to how self-efficacy is discussed by students: 1) self-efficacy is developed differently between the two programs because the tasks associated with each program are different; 2) GE students discuss self-efficacy more broadly regarding engineering in general, focusing on domains like professional skills; 3) DE students discuss self-efficacy development more narrowly, specifically related to being an electrical or computer engineer. Additionally, the findings from study 2 suggest that pedagogical structures may be more important regarding self-efficacy development than matriculation structures. These results broaden our understanding of how FYE programs impact self-efficacy development within the context of a specific major, but still lend themselves to further exploration regarding factors most related to persistence and the experiences of underrepresented minorities in engineering.
Doctor of Philosophy
While first-year engineering (FYE) programs have grown dramatically over the last 30 years, they take a variety of different structures. However, few if any, researchers and FYE program developers have considered how program structure impacts persistence – an issue that continues to be of concern as we seek to grown the national engineering workforce. Low retention rates combined with lack of diversity in the field becomes even more intense when considering the field of Electrical and Computer Engineering (ECE) which ranks as one of the least diverse engineering disciplines. One factor that has been shown to support retention is self-efficacy or individuals' beliefs in their ability to succeed. Therefore, to help address the retention issues in ECE, this dissertation explores the programmatic influence of first-year engineering matriculation structures on self-efficacy development in electrical and computer engineering students. In particular, it compares declared engineering (DE) programs, which admit students to a specific engineering field, to general engineering (GE) programs, in which students are admitted to engineering but do not select a specific engineering field until after their first year. The dissertation includes three studies: 1) a quantitative comparison of expectancy (similar to self-efficacy) beliefs in a GE program and a quasi- DE first-year engineering program for ECE students; 2) a qualitative study of self-efficacy development in a DE first-year program using interviews with students; and 3) a qualitative study of similarities and differences in self-efficacy development in EE students at two universities, one with a DE program and one with a GE program. The studies demonstrated similarities in self-efficacy development in students from the DE and GE programs, with differences largely attributed to how students described self-efficacy, as follows: 1) self-efficacy is developed differently between the two programs because the tasks associated with each program are different; 2) GE students discuss self-efficacy more broadly regarding engineering in general, focusing on issues like professional development skills; 3) DE students discuss self-efficacy development more narrowly, specifically related to being an electrical or computer engineer. Additionally, the findings from study 2 suggest that approaches to teaching may be more important for self-efficacy development than matriculation structures. These results broaden our understanding of how FYE programs impact self-efficacy development within the context of a specific major, but also point to the need for more research on factors most related to persistence and the experiences of underrepresented minorities in engineering.

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Goel, Vishu. "Novel coating technologies for electrical steels." Thesis, Cardiff University, 2016. http://orca.cf.ac.uk/93813/.

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Power loss in transformer cores accounts for approximately 5% of the energy lost as heat. The loss could be reduced by improving the secondary recrystallization methods, grain orientation control, increasing the electrical resistivity of the steel, reducing the thickness of laminations, manipulating the domain structure and applying coatings. Coating grain oriented electrical steel (GOES) helps in reducing the loss by providing electrical resistance, improving the surface roughness and applying beneficial tensile stress. In this work a range of coatings were explored that can be economically applied on GOES to reduce power loss and magnetostriction in working transformers. Coatings were investigated using a range of coating processes including electroless plating, thermal evaporation physical vapour deposition and electron beam physical vapour deposition. The coatings were characterised using a range of processes including Single Strip Testing (SST), Magnetostriction measurement, Vibrating Sample Magnetometer (VSM), magnetic domain imaging, Optical microscopy, Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Spectroscopy (EDS), X-ray Diffraction (XRD), Surface profilometry, Atomic force microscopy and Raman spectroscopy. Co-Ni-P applied on GOES improved the magnetic properties by applying beneficial tensile stress which aligns the domains in the direction of magnetization and by improving the surface roughness which reduces the number of pinning sites on the surface of steel. The magnetostriction was improved due to the effect of beneficial tensile stress. Similarly Co-PCNT applied on GOES reduced the power loss by improving the surface roughness. CrN, CrAlN, TiAlN improved the power loss and magnetostriction as tensile stress was applied by the coatings which reduced the domain width and hence loss was reduced. The reduction in magnetostriction was due to the high value of Young’s modulus of the coatings as compared to GOES which did not allow the steel to expand under the influence of applied magnetic field. The ceramic coatings could be directly employed in the production line replacing the phosphate coating unit with the Chemical/Physical vapour deposition.

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Akyol, Fatih. "Nanoscale Electron Transport Engineering for GaN Optoelectronic Devices." The Ohio State University, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=osu1462897011.

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Kuc, Bernard. "Evaluation of virtual reality technology for control engineering." Master's thesis, University of Cape Town, 1999. http://hdl.handle.net/11427/16093.

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Includes bibliography.
Virtual Reality technology has over recent years become available for commercial use. Where initially it had only been available to research centres and the military, it is now accessible to the industrial and commercial sectors. What this dissertation covers is the suitability of the low cost end of the Virtual Reality hardware for use in Control Engineering. The use of Virtual Reality within Control Engineering could impart significant advantages over traditional control rooms currently in use in factories. The primary one, as rated by most commercial ventures, would be the cost saving of replacing all the physical hardware in a control room with virtual counter-parts in software. This is assuming that the Virtual Reality hardware will itself be of sufficiently low cost. The second is its ability to be used for operator training in instances where factors of safety and economics cannot allow for mistakes to be made on the real plant. A third advantage of a virtual control room, is its portability. As long as the factory can be accessed through some computer network, then the control room can be moved to any desired location. For example a copy of the control room for each factory can be maintained at head office where a chief engineer can occasionally check up on plant performance.

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Lehr, Rainer Helmut. "Web based distance learning for power system engineering." Master's thesis, University of Cape Town, 2000. http://hdl.handle.net/11427/5186.

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31

Wang, Yingxu. "Software engineering process modelling analysis." Thesis, Southampton Solent University, 1998. http://ssudl.solent.ac.uk/2429/.

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Studies of the software engineering process are a natural extension of scope from that of conventional software development methodologies meeting the requirement for engineering large-scale software development. A new approach for dealing with the difficulties of large-scale software development in software engineeering is to establish an appropriate software engineering process system. This work researches into software engineering process system modelling and analysis. The delivered aims of this thesis are to investigate empirical software engineering process research and practices to solve current problems identified in software engineering process system modelling, to integrate current process models into a well founded and unifying framework and to lay theoretical foundations for the software engineering process as a formalised discipline.

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Vieri, Carlin James. "Reversible computer engineering and architecture." Thesis, Massachusetts Institute of Technology, 1999. http://hdl.handle.net/1721.1/80144.

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Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1999.
Includes bibliographical references (p. 162-165).
by Carlin James Vieri.
Ph.D.

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33

Slottow, Edward C. (Edward Colin). "Engineering a global resolution service." Thesis, Massachusetts Institute of Technology, 1997. http://hdl.handle.net/1721.1/43506.

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Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1997.
Includes bibliographical references (p. 99-100).
by Edward C. Slottow.
M.Eng.

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34

Ye, Yufeng S. M. Massachusetts Institute of Technology. "Nonlinearity engineering with the Quarton." Thesis, Massachusetts Institute of Technology, 2020. https://hdl.handle.net/1721.1/127318.

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Thesis: S.M., Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, May, 2020
Cataloged from the official PDF of thesis.
Includes bibliographical references (pages 59-62).
In this thesis, we show the principles and applications of a new technique we call "nonlinearity engineering" using a recent superconducting qubit, the Quarton. In traditional nonlinear optics, nonlinear effects are usually weak perturbations to linear interactions. Similarly, microwave quantum optics with superconducting circuits relies on the Josephson junction for a negative Kerr nonlinearity that is much weaker than its associated linear energy. Recently, a new superconducting qubit known as the "Quarton" can offer non-perturbatively strong nonlinearity. Here, we demonstrate the general principle of using the Quarton's positive Kerr and zero linear energy to perform nonlinearity engineering, i.e. the selective design of the nonlinear properties of microwave artificial atoms, metamaterials, and photons in a manner that (to the best of our knowledge) has no optical analog. We show that for Quarton mediated light-matter coupling, the Quarton can erase or amplify the nonlinearity of artificial atoms and metamaterials. Without nonlinearity, matter behaves light-like and we find (to our best knowledge) the first theoretical demonstration of cross-Kerr between linear microwave photon modes. We extend these fundamental results and provide a practical application by designing a Josephson traveling wave photon detector
by Yufeng Ye.
S.M.
S.M. Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science

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35

Gao, Fei. "Decentralised control and stability analysis of a multi-generator based electrical power system for more electric aircraft." Thesis, University of Nottingham, 2016. http://eprints.nottingham.ac.uk/37955/.

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The more electric aircraft initative results in significant challenges in the design of aircraft electrical power systems. Different power system architectures are currently being studied by the engineering community. In this thesis, a promising single DC bus-based, multiple-source multiple-load power system is investigated in terms of power management and stability. Due to its inherent modularity and ease of implementation, droop control, as a decentralised control method, has been widely used to cope with power sharing among parallel sources in the studied architecture. The thesis proposes a comparative study of different droop control approaches by focusing on steady-state power sharing performance and stability. • Different droop control methods may lead to different stability margins. Until now, the effect of different droop control schemes on system stability has not been fully investigated. The thesis presents the control scheme for current-mode and voltage-mode systems, derives the corresponding output impedance of the source subsystem and analyses the stability of the power system. Based on the developed mathematical model, comprehensive modal analysis of the power system is performed. • A generalised analytical impedance analysis is extended to a multi-source multi-load power system. To facilitate the analysis, the thesis proposes the concept of “global droop gain” as an important factor to determine the V-I bus characteristic and the stability behaviour of a parallel sources based DC system. • Considering the tradeoff between voltage regulation and power sharing accuracy in droop control, this thesis proposes an improved voltage regulation method in multi-source based DC electrical power system. Due to the absence of additional controllers or communication lines, the proposed approach can be relatively easily implemented in a small scale DC electrical power system. The proposed approach effectively improves the load sharing accuracy under high droop gain circumstances with consideration of cable impedance. Optimal droop gain settings are investigated and the selection of individual droop gains has been described in order to reduce the distribution losses. Finally, the above-mentioned analytical results are confirmed by time-domain simulations and experimental results.

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Zhang, Yuxi Ph D. Massachusetts Institute of Technology. "Electrospun nanofibers with tunable electrical conductivity." Thesis, Massachusetts Institute of Technology, 2013. http://hdl.handle.net/1721.1/81690.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Chemical Engineering, 2013.
Cataloged from PDF version of thesis.
Includes bibliographical references (p. 114-117).
Electrospinning is a convenient method to produce nanofibers with controlled diameters on the order of tens to hundreds of nanometers. The resulting nonwoven fiber mats are lightweight, highly porous, and have high specific surface areas around 1 to 100 m2/g. Combined with the high electrical conductivity of intrinsically conductive polymers, conductive electrospun fiber mats are promising for a variety of applications, such as multifunctional textiles, resistance-based sensors, flexible reversibly hydrophobic surfaces, organic photovoltaics, scaffolds for tissue engineering, and conductive substrates for surface functionalization and modification Intrinsically conductive polymers, such as polyaniline (PAni), however, are relatively hard to Intrinsically conductive polymers, such as polyaniline (PAni), however, are relatively hard to process compared to most other polymers. They have fairly rigid backbones due to the high aromaticity, and are usually available only in relatively low molecular weight forms, so that the elasticity of their solutions is insufficient for it to be electrospun directly into fibers. Considerable amount of recent work has been reported trying to make electrospun polymeric nanofibers with intrinsically conductive polymers or composites. However, a large fraction of the work only showed the morphology and did not characterize the actual performance of these fibers, nor did they test the variability of the fibers and mats from a wide range of processing conditions and resulting structures. Therefore, this thesis aims to make a comprehensive study of the electrical tunability of electrospun fibers with intrinsically conductive polymers and its composites, to establish a clear processing-structure-property relationship for these fibers and fiber mats, and to test the resultant fibers with the targeted applications such as gas sensing. We have first developed a reliable method to characterize fiber electrical conductivity using interdigitated electrodes (IDE) and high-impedance analyzers with contact-resistance corrections, and applied to electrospun conductive polymer nanofibers. This method was shown to be reliable and sensitive, as opposed to some of the other methods that have been reported in literature. Facing with the challenge of overcoming the relatively low elasticity of the conductive polymer solutions to achieve electrospinnability, we have fabricated electrospun fibers of PAni and poly(3,4-ethylenedioxythiophene) (PEDOT), blended with poly(ethylene oxide) (PEO) or poly(methyl methacrylate) (PMMA) over a range of compositions. Pure PAni (doped with (+)- camphor-i 0-sulfonic acid (HCSA)) fibers were successfully fabricated for the first time by co-axial electrospinning and subsequent removal of the PMMA shell by dissolution. This allowed for the pure electrospun PAni/HCSA fibers to be tested for electrical performances and its enhancement as well as gas sensing application. The conductivities of the PAni-blend fibers are found to increase exponentially with the weight percent of doped PAni in the fibers, to as high as 50 ± 30 S/cm for as-electrospun fibers of 100% PAni/HCSA. This fiber conductivity of the pure doped PAni fibers was found to increase to 130 ± 40 S/cm with increasing molecular orientation, achieved through solid state drawing. The experimental results thus support the idea that enhanced molecular alignment within electrospun fibers, both during the electrospinning process and subsequent post-treatment, contributes positively to increasing electrical conductivity of conductive polymers. Using a model that accounts for the effects of intrinsic fiber conductivity (including both composition and molecular orientation), mat porosity, and the fiber orientation distribution within the mat, calculated mat conductivities are obtained in quantitative agreement with the mat conductivities measured experimentally. This correlation, along with the reliable method of fiber conductivity measurement by IDE, presents a way to resolve some of the inconsistencies in the literature about reporting electrical conductivity values of electrospun fibers and fiber mats. Pure PAni fibers with different levels of doping were also fabricated by co-axial electrospinning and subsequent removal of the shell by dissolution, and shown to exhibit a large range of fiber electrical conductivities, increasing exponentially with increasing ratio of dopant to PAni. These fibers are found to be very effective nanoscale chemiresistive sensors for both ammonia and nitrogen dioxide gases, thanks to this large range of available electrical conductivities. Both sensitivity and response times are shown to be excellent, with response ratios up to 58 for doped PAni sensing of ammonia and up to more than 105 for nitrogen dioxide sensing by undoped PAni fibers. The characteristic times for the gas sensing are shown to be on the order of 1 to 2 minutes. We have also developed a generic time-dependent reaction-diffusion model that accounts for reaction kinetics, reaction equilibrium, and diffusivity parameters, and show that the model can be used to extract parameters from experimental results and used to predict and optimize the gas sensing of fibers under different constraints without the need to repeat experiments under different fiber and gas conditions.
by Yuxi Zhang.
Ph.D.

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37

Proctor, Laura L. (Laura Lynne) 1975. "Tissue electrical impedance determination via microneedles." Thesis, Massachusetts Institute of Technology, 2002. http://hdl.handle.net/1721.1/89893.

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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2002.
MIT Institute Archives copy bound: p. 1-78, 81-82, 79-80, 83-101.
Vita.
Includes bibliographical references (p. 81-84).
by Laura L. Proctor.
S.M.

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38

Cho, Margaret H. (Margaret Hyunjoo) 1982. "Environmental constituents of Electrical Discharge Machining." Thesis, Massachusetts Institute of Technology, 2004. http://hdl.handle.net/1721.1/32827.

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Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2004.
Includes bibliographical references (leaves 30-31).
Electrical Discharge Machining (EDM) is a non-traditional process that uses no mechanical forces to machine metals. It is extremely useful in machining hard materials. With the advantages EDM has to offer and its presence as a common and useable technique, along with the other machining processes available to the industrial world, there is an added strain on the environment. The scope of this thesis includes analyzing the various inputs into EDM and the resulting outputs into the environment. A simplified model is used to analyze the process. The main categories of flow scrutinized in the model are material flow and energy flow. The most hazardous effect to the environment is found in the resin interaction of the wire EDM process where depending on the type of material machined, there is a potential presence of hazardous materials. There are efforts to recycle all salvageable materials such as wire and metal wastes, but currently no accountability system exists as manufacturers are responsible for their actions.
by Margaret H. Cho.
S.B.

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39

Lanka, Avinash. "Electrical Characterization and Applications of Supercapacitors." Wright State University / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=wright1472052551.

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40

Ventura, John. "Web-Based evaluation Process for an Electrical and Computer Engineering Department." NSUWorks, 2006. http://nsuworks.nova.edu/gscis_etd/897.

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National and regional accrediting agencies require educational institutions to provide evidence that indicate the fulfillment of program objectives and generate results for improvement of curriculum. The Accreditation Board for Engineering and Technology (ABET) requires programs to develop and implement an evaluation process for assessing learning outcomes, reviewing achievement in the workplace by recent graduates of the program, and formulating a course of action for quality improvement of the program. Accrediting agencies require a structured plan to measure and evaluate learning outcomes and objectives, as defined by a program. They do not stipulate the methods to be used in the development of assessment and evaluation processes. However, they require that institutions demonstrate the andragogy used to achieve objectives as well as evidence of assessment and plans for continuous improvement. The study developed an evaluation model that included seven surveys for measuring the achievement of program objectives and learning outcomes, methods for scoring the results of these surveys, and techniques for presenting and comparing the measurements obtained. Committees were formed to represent industry, professional organizations and societies, science department, master’s program, local conference leaders, faculty, and IEEE student branch. The committees assessed the evaluation model. Web-based technologies were employed to deliver the surveys to students, faculty, alumni, and industry. These browser-based instruments were password protected to provide security to constituents. The university online survey system provided a database for storing data to be assessed over several semesters or terms of assessment for comparing results and determining trends.

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41

Smith, Philip Hartley. "Electrical Distribution Modeling:An Integration of Engineering Analysis and Geographic Information Systems." Thesis, Virginia Tech, 2005. http://hdl.handle.net/10919/36158.

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This thesis demonstrates the value of integrating electrical distribution engineering analysis with Geographic Information Systems (GIS). The 37-Node IEEE Feeder model was used as the base distribution system in this study. It was modeled separately, both in software capable of unbalanced load-flow and in an industry-standard GIS environment. Both tools utilized were commercially available, off-the shelf products indicative of those used in academia and in basic GIS installations. The foundational data necessary to build these models is representative of information required by a variety of utility departments for a multitude of applications. It is inherent to most systems within an enterprise-level, business-wide data model and therefore can be used to support a variety of applications. In this instance, infrastructure information is assumed to be managed and housed with the GIS. This data provides the required information as input for load-flow calculations. The engineering analysis is performed within DistributionSystem 4.01 and its output is passed back to the GIS in tabular format for incorporation. This thesis investigates the transfer of information between GIS and DistributionSystem 4.01 and demonstrates the extended display capabilities in the GIS environment. This research is implemented on a small scale, but is intended to highlight the need for standardization and automatic integration of these systems as well as others that are fundamental to the effective management of electrical distribution systems.
Master of Science

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42

Bandhakavi, Sri Lalitha. "Diversity Management Policies and Practices : Of a Swedish Electrical Engineering MNC." Thesis, Högskolan Dalarna, Institutionen för kultur och samhälle, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:du-37575.

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Purpose The purpose of this study is to identify the causes and benefits of workforce diversity in a Swedish electrical engineering multinational corporation. Furthermore, to identify various challenges faced by the managers in diversity management and to find strategies adopted by them to minimize those challenges. Design/Methodology/Approach For this research qualitative method is undertaken. The research was undertaken in two stages. In stage one, an open-ended questionnaire was used to collect primary data from three line-managers and in stage two focused group discussion was conducted with three employees from HR department. The total sample size is six employees working in a Swedish Electrical Engineering MNC. Findings and Conclusions The nature of the business carried by the studied MNC requires continuous innovation and customization of products, which requires employees with diverse knowledge, skills and capabilities. The causes for diversity in the studied organization are because of encouraging internal movement of employees from various subsidiaries to the headquarters and by using various other staffing practises such as inpatriation, global virtual teams, permanent transfers etc. The company is also hiring employees from diverse jobmarkets. The findings from the primary data shows that the studied MNC is benefited from highly diversified work force. However, there are certain challenges faced by managers in managing diversity. The Diversity 360 policy of the company is helping the studied MNC to overcome the challenges in diversity management.

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43

Risemark, Eriksson Martin. "Environmental stress of electrical machine winding insulation." Thesis, Uppsala universitet, Elektricitetslära, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-326711.

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The conducting winding of an electrical machine is insulated in order to prevent any short circuits to occur within the machine. This insulation is during its lifetime exposed to several environmental stresses and therefore plays an important role in the life length of the machine. Accelerated stress tests are used to investigate what design and material is most suitable for a good endurance of a product. In this master thesis, new accelerated test methods for the insulation system in an electrical machine are developed and evaluated. The study resulted in four stress tests that simulate the thermal stress, the thermomechanical stress and the ambient stress from direct oil cooling. Three diagnosis tests and a material analysis were used in order to evaluate how these accelerated stress test methods affected the insulation. The diagnosis tests showed no clear sign of deterioration of the insulation in terms of change in electrical characteristics. However, the material analysis indicated deterioration of the insulation, such as cracks and oxidation of the material. These changes show that the test methods are capable to affect the insulation, but will need more time to cause a breakdown, since a stator of this kind is expected to have a very long life length. Therefore, in future work on this topic, these test methods should continue for a longer time and it would likely be interesting to look into other diagnosis tests.

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Henning, Pieter Hendrik. "Control of a 1.5 MW active power filter and regeneration converter for a Spoornet DC traction substation." Thesis, Stellenbosch : University of Stellenbosch, 2005. http://hdl.handle.net/10019.1/2340.

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Thesis (MScEng (Electrical and Electronic Engineering))--University of Stellenbosch, 2005.
Although regenerative braking has been in used in railway systems for a long time already, the energy generated was dissipated in resistor banks. The rapid advances in the power electronics field, accompanied by the development of faster and higher power switching devices in recent years, now make it possible to convert the regenerated electrical energy from DC to AC, which can then be injected into the Eskom grid. A 1.5 MW full scale prototype system was built, installed and tested in a Spoornet DC traction substation. A seven level series-stacked converter topology was used along with a specially designed injection transformer. The system was controlled by the PEC 33 controller board, which was developed at the University of Stellenbosch. The primary function of the system is to function as a regeneration converter and as a secondary function act as an active power filter.

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45

Berrie, Jeffery A. "Measurement of electrical parameters for planar materials /." The Ohio State University, 1992. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487759436328874.

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Hierro, Adrian. "Electrical characterization of defects in n-GaN /." The Ohio State University, 2001. http://rave.ohiolink.edu/etdc/view?acc_num=osu1488204276532651.

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47

Shahaj, Annabel. "Mitigation of vibration in large electrical machines." Thesis, University of Nottingham, 2010. http://eprints.nottingham.ac.uk/11337/.

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In this study two new technologies are investigated with a view to improving the efficiency and reducing the vibrations of large electrical machines. These machines are used for high powered industrial applications. Individually controlled conductors are part of an active stator project that Converteam Ltd are developing. This involves individual conductors located in each stator slot that can be controlled separately. These replace traditional polyphase windings in order to provide a high level of control over the operation of the machine. A linear magneto-mechanical finite element model has been used here to show that this control method can enable a 44% reduction in the copper loss from the machine compared to a sinusoidal supply whilst maintaining the same operational torque. This method introduces extra Fourier harmonics into the excitation pattern supplied to the machine that are not present in the supply current to traditional polyphase windings. These extra harmonics utilize saliency advantageously to produce torque. However, they also increase the vibration of the stator and may increase hysteresis loss in the iron. The bimorph concept is an idea that is unique to this thesis. This concept involves individually controlled conductors positioned through the root of each stator tooth. On application of a relatively small power input to these conductors a magnetic field is created in the stator which distorts the existing magnetic field. Under certain conditions, the magnetostriction phenomenon causes the teeth to act as a vibration absorber. The effect of this method on the Maxwell forces in the air gap is small. This enables the cancellation of components of vibration of the stator whilst the machine torque is maintained. This is a vibration control method suited to high frequency vibrations where the deformed shape of the stator includes a rocking motion of the teeth and where the resultant stator vibrations lead to tonal noise emission from the machine. This thesis investigates the two technologies mentioned above with a magnetomechanical finite element model and two experimental investigations. The thesis also contains background information relevant to this study including an introduction to electrical machines and power electronics, noise radiation and sources of noise in electrical machines, finite element modelling, vibrations of electrical machines and vibration absorbers.

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Kampisios, Konstantinos T. "Electrical machines parameter identification using genetic algorithms." Thesis, University of Nottingham, 2010. http://eprints.nottingham.ac.uk/14005/.

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In Indirect Field Orientation (IFO) of induction motors, the interest for parameters identification has increased rapidly due to the great demand for high performance drives and more sophisticated control systems that have been made possible by the development of very powerful processors, such as floating point DSPs. Accurate knowledge of the machine electrical parameters is also required to ensure correct alignment of the stator current vector relative to the rotor flux vector, to decouple the flux - and torque - producing currents and to tune the current control loops. The accuracy and general robustness of the machine is dependant on this model. Artificial intelligent technologies have been tested in the field of electro mechanics like neural networks, fuzzy logic, simulated annealing and genetic algorithms. These methods are increasingly being utilised in solving electric machine problems. This thesis addresses a novel non - intrusive approach for identifying induction motor equivalent circuit parameters based on experimental transient measurements from a vector controlled Induction Motor (I.M.) drive and using an off line Genetic Algorithm (GA) routine with a linear machine model. The evaluation of the electrical motor parameters at rated flux operation is achieved by minimising the error between experimental responses (speed or current) measured on a motor drive and the respective ones obtained by a simulation model based on the same control structure as the experimental rig. An accurate and fast estimation of the electrical motor parameters is so achieved. Results are verified through a comparison of speed, torque and line current responses between the experimental IM drive and a Matlab - Simulink model. The second part of the research work introduces a new approach based on heuristic optimisation for identifying induction motor electrical parameters under different operating conditions such as different load and flux levels. Results show via interpolation test the effect of the most important electrical parameters, the magnetising inductance Lm and rotor resistance Rr, at each different operating condition.

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Patel, Muneeza S. "Algorithms for E. coli genome engineering." Thesis, Massachusetts Institute of Technology, 2016. http://hdl.handle.net/1721.1/106461.

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Thesis: M. Eng. in Computer Science & Molecular Biology, Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, 2016.
This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
"June 2016." Page 90 blank. Cataloged from student-submitted PDF version of thesis.
Includes bibliographical references (pages 70-72).
Author summary: Lamba red recombineering is one of methods of performing genome engineering. However, this method of genome editing is not very specific and efficient and is highly dependent on the genomic regions that are targeted (integration sites). In this project we explored ways of identifying what makes a site well suited for lambda red genome engineering. We wanted to explore whether we can eventually predict the "goodness" of an integration site using an algorithm. Our initial approach to the problem was to write an algorithm based on some characteristics that we felt would be key to determining the goodness of a site. Choosing to initially focus on specificity of the integrations, we used experimental approaches to evaluate whether our algorithm had any predictive powers for specificity. Upon failing, we revised our plan to generate a dataset of ~150 sites and their integration data (whether integration was successful, specific and efficient at that site). We used this dataset to explore correlations between the specificity data and characteristics we thought might affect the specificity of sites. The most promising characteristics appeared to be the uniqueness of the genomic site (as determined by BLAST) and the existence of Repetitive Extragenic Palindrome (REP) sites at the site of integration. Section I of this thesis sets up the problem, section II talks about the initial approach we took to the problem and section III discusses our modified approach -- which formed the bulk of this thesis project. Section I and III are the most relevant to understand the project, while Section II gives more content to the project in addition to detailed insight to what approaches did not work.
by Muneeza S. Patel.
M. Eng. in Computer Science & Molecular Biology

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Yang, Bob 1976. "Managing a distributed software engineering team." Thesis, Massachusetts Institute of Technology, 1998. http://hdl.handle.net/1721.1/50394.

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Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science; and, Thesis (B.S.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1998.
Includes bibliographical references (leaves 97-98).
by Bob Yang.
B.S.
M.Eng.

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Dissertations / Theses on the topic 'Electrical Engineering'

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