Página 1 dos resultados de 5181 itens digitais encontrados em 0.029 segundos

A unified theory of flow control and routing in data communication networks

Golestaani, Seyyed Jamaaloddin
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 94 leaves; 5064620 bytes; 5064383 bytes; application/pdf; application/pdf
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by Seyyed Jamaaloddin Golestaani.; Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1980.; MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING.; Includes bibliographical references.

Modelling and analysis of unreliable manufacturing assembly networks with finite storages

Ammar, Mostafa H. (Mostafa Hamed)
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 163 leaves; 6667798 bytes; 6667556 bytes; application/pdf; application/pdf
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by Mostafa Hamed Ammar.; Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1980.; MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING.; Bibliography: leaves 160-163.

Low power-electrical isolation for EKG monitoring equipment

Turkel, David Howard
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: [1], 40 leaves; 3259144 bytes; 3258906 bytes; application/pdf; application/pdf
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by David Howard Turkel.; Thesis (B.S.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1979.; MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING.; Includes bibliographical references.

The design of a conservative logic computer and a graphical editor simulator

Ressler, Andrew Lewis
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 128 leaves; 7002152 bytes; 7001908 bytes; application/pdf; application/pdf
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by Andrew Lewis Ressler.; Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1981.; MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING.; Bibliography: leaf 128.

Enhancement of catalog processing system for MIT Science Fiction Society

Wheeler, Cheryl Ann
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 51 leaves; 2047023 bytes; 2046783 bytes; application/pdf; application/pdf
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by Cheryl Ann Wheeler.; Thesis (B.S.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1982.; MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING; Includes bibliographical references.

Design and measurement of a reconfigurable multi-microprocessor machine

Zukowski, Charles
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 156 leaves; 8382087 bytes; 8381842 bytes; application/pdf; application/pdf
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by Charles Zukowski.; Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1982.; MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING; Includes bibliographical references.

The principles of design applied to engineering and policy

Filippone, Stephen Francis
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 124 leaves; 11696392 bytes; 11696152 bytes; application/pdf; application/pdf
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by Stephen Francis Filippone.; Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1988.; Includes bibliographical references.

VISTA : a visualization tool for computer architects; Visualization tool for computer architects

Mihalik, Aaron D. (Aaron Daniel), 1980-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 55 leaves; 3599683 bytes; 3605553 bytes; application/pdf; application/pdf
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As computer architectures continue to grow in complexity, software developers and hardware engineers cope with the increasing complexity by developing proprietary applications, simulations and tool sets to understand the behavior of these complex systems. Although the field of information visualization is leading to powerful applications in many areas, information visualization applications for computer architecture development are either tightly coupled with a specific architecture or target a wide range of computer system data. This thesis introduces the Visualization Tool for Computer Architects (VISTA) Environment. The VISTA Environment is an extensible and modular information visualization environment for hardware engineers, software developers and educators to visualize data from a variety of computer architecture simulations at different levels of abstraction. The VISTA Environment leverages common attributes in simulation data, computer architecture visualizations, and computer architecture development methods to create a powerful information visualization environment to aid in designing, understanding and communicating complex computer architectures.; by Aaron D. Mihalik.; Thesis (M. Eng.)--Massachusetts Institute of Technology...

Corporate housekeeping knowledge engineering and processing using extended COIN; Corporate housekeeping knowledge engineering and processing using extended COntext INterchange

Xian, Xiang, 1979-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 76 p.; 4621156 bytes; 4620964 bytes; application/pdf; application/pdf
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by Xiang Xian.; Thesis (M.Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2003.; Includes bibliographical references (p. 55-56).

An optical-electrical sub-sampling down-conversion receiver with continuous-time [Sigma] [Delta] modulation

Park, Matthew (Matthew J.)
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 89 p.; 3414261 bytes; 3417910 bytes; application/pdf; application/pdf
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This thesis describes the design and implementation of an optical-electrical sub-sampling down-conversion receiver that employs [Sigma] [Delta] modulation. Accurate sub-sampling of an electrical RF signal in the optical domain is achieved by using a low-jitter mode-locked-laser and a high-bandwidth interferometer. The sub-sampled information is then digitized by an optical-electrical continuous-time (CT) [Sigma] [Delta] analog- to-digital converter (ADC). Here, photodiodes and low-jitter pulses from the mode- locked-laser are leveraged to perform signal clocking and quantizer pre-amplification, overcoming digital-to-analog converter (DAC) clock jitter and quantizer metastability issues that plague traditional electronic implementations. The optical-electrical converter achieves 76.5 dB of SNR (12.4 ENOB) with a 1 MHz signal bandwidth and a sampling rate of 780 MHz. The chip was implemented using a standard bulk 0.18 [mu]m CMOS process from National Semiconductor, occupies a total area of 3 mm2, and consumes 45 mW of power.; by Matthew Park.; Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2005.; In title on t.p., [Sigma] and [Delta] appear as the upper-case Greek letters.; Includes bibliographical references (p. 87-89).

Extensions and enhancements to the iLab heat transfer project site

Saylor, David P. (David Patrick)
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 74 p.
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The iLab Heat Transfer Project website started four years ago to enable web access to experiments related to movement of heat through transport processes. This thesis details improvements made to the site which extend and enhance the site prior to the project. Software improvements include giving teaching assistants the ability to add their entire class as users simultaneously and creating a method by which feedback data is stored as a full questionnaire instead of database entries. Hardware improvements include the addition of a webcam that streams video and audio of the experiment in real time and the integration of two new thermodynamic experiments complete with remote access. The final improvement is the administrator manual, which is intended to ease the burden on new staff members by bridging their knowledge with that of previous years.; by David P. Saylor.; Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, September 2005; and, (S.B.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, June 2004.; "September 5, 2005." "Copyright 1998."; Includes bibliographical references (p. 74).

Control and design of multi-use induction machines : traction, generation, and power conversion

Avestruz, Al-Thaddeus
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 159 p.
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An electrical machine can be made to convert electrical power while performing in its primary role of transforming electrical energy into mechanical energy. One way of doing this is to design the machine with multiple stator windings where one winding acts as a primary for drive and power, and the others as secondaries for electrical power. The challenge is to control the mechanical outputs of torque and speed while independently regulating the electrical outputs of voltage and current. This thesis analyzes and demonstrates an approach that takes advantage of topological symmetries in multiphase systems to overcome this challenge. This method is applied, but not relegated to induction machines.; by Al-Thaddeus Avestruz.; Thesis (S.M. and Elec. E.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2006.; Includes bibliographical references (p. 157-159).

Analysis of system wide distortion in an integrated power system utilizing a high voltage DC bus and silicon carbide power devices

Fallier, William F. (William Frederick)
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 172 p.
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This research investigates the distortion on the electrical distribution system for a high voltage DC Integrated Power System (IPS). The analysis was concentrated on the power supplied to a propulsion motor driven by an inverter with simulated silicon carbide switches. Theoretically, silicon carbide switches have the advantage of being able to withstand a very large blocking voltage and carry very large forward currents. Silicon carbide switches are also very efficient due to their quick rise and fall times. Since silicon carbide switches can withstand high voltage differentials and switch faster than silicon switches, the switching effects on the electrical distribution system were investigated. The current state of silicon carbide power electronics was also investigated. This research quantifies the current and voltage distortion over various operating conditions. A system model was developed using Matlab, Simulink, and SimPowerSystems. The model consisted of a synchronous generator supplying a rectifier and inverter set driving an induction motor. This induction motor simulates the propulsion motor for a Navy ship. This model had a DC link voltage of 10 kV in order to simulate future Navy IPS systems. The current and voltage distortion were compared to MIL STD 1399 and IEEE STD 519 and 45.; by William F. Fallier.; Thesis (Nav. E.)--Massachusetts Institute of Technology...

Electrical degradation mechanisms of RF power GaAs PHEMTs

Villanueva, Anita A. (Anita Ariel), 1978-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 163 p.
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GaAs Pseudomorphic High-Electron Mobility Transistors (PHEMTs) are widely used in RF power applications. Since these devices typically operate at high power levels and under high voltage biasing, their electrical reliability is of serious concern. Previous studies have identified several distinct degradation phenomena in these devices, but a complete picture has yet to be formed. In this study, we have carried out a comprehensive study of the mechanisms of electrical degradation on a set of experimental RF power GaAs PHEMTs (non-commercial devices provided by our sponsor, Mitsubishi Electric). A wide variety of electrical stressing experiments employing different conditions (varying temperature, bias, environment) were performed on these devices in order to monitor their degradation with stressing. Our general observations showed several forms of degradation, the most concerning being an increase in the drain resistance RD and a reduction in maximum drain current Imax. Contrary to what is often claimed in the literature, our experiments indicated that these forms of degradation were not driven by impact-ionization or hot-electron effects. Instead, we found the degradation to be strongly correlated with temperature, stressing environment...

ELVIS iLab : a flexible platform for online laboratory experiments in electrical engineering; Flexible platform for online laboratory experiments in electrical engineering

Gikandi, Samuel
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 83 leaves
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This thesis describes a project that is part of the collaboration between MIT and universities in sub-Sahara Africa to exploit the value of iLabs in the developing world. The main goal of this project is to develop software that will exploit the value of the National Instruments Educational Laboratory Virtual Instrumentation Suite (ELVIS) system in Africa by integrating it into the iLabs shared architecture, while taking into consideration the special circumstances surrounding the deployment of iLabs in Africa such as bandwidth limitations, limited access to networked computers and lack of computer skills on the part of students. Integrating ELVIS into iLabs will facilitate the rapid deployment of new online labs to augment the Physics and Electrical engineering curricula in these universities. iLab development efforts for this project are being done in parallel with developers at the Obafemi Awolowo University (OAU) in Nigeria. One of the main goals of the new system is to fill the gap of laboratory experiences in introductory level electronics and physics classes, which are hardest hit by the lack of equipment due to their typically large enrollment. Our goal is to support the development of electronic circuit building skills by providing an environment where students can easily try different circuit configurations before submitting experiments for execution. We are therefore investigating new iLab client user interface designs that will enable students to create and edit circuit schematics from provided electronic components. Our ELVIS iLab design will also formalize and simplify the process of creating and administering such labs for instructors...

Modular development of an educational remote laboratory platform for electrical engineering : the ELVIS iLab; ELVIS iLab

Jiwaji, Adnaan
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 76 p.
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iLabs are remote online laboratories that allow users to perform experiments through the Internet. As an educational tool the iLab platform enables students and educators, who do not have access to laboratories, to complement their theoretical knowledge by carrying out experiments remotely on equipment located anywhere in the world and at any time of the day. Students perform experiments on actual instruments allowing them to get real data, instead of relying on simulations. The iLab project has been deployed in 3 universities in Africa using the National Instruments Educational Laboratory Virtual Instrument Suite platform which is a cheap all-in-one electronics workstation for electronics experiments. This thesis describes an increase in the functionality available on the current version of the ELVIS iLab in order to enable a wider range of experiments to be run on the platform. The functionalities explored include adding two arbitrary waveform generator channels and bode analyzer for frequency domain analysis, which was not possible in the previous designs.; by Adnaan Jiwaji.; Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2008.; This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.; Includes bibliographical references (p. 75-76).

Biomimetic electrical stimulation for cardiac tissue engineering

Tandon, Nina
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 75 leaves
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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.; Thesis (S.M.)--Massachusetts Institute of Technology...

Dielectrometry measurements of moisture diffusion and temperature dynamics in oil impregnated paper insulated electric power cables

Thomas, Zachary M. (Zachary Michael)
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 452 p.
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Paper insulated lead covered (PILC) cables have played an important role in underground power distribution for a hundred years. Replacing aged PILC before failure is critical to managing power distribution. Three prominent failure mechanisms accelerate cable aging: temperature stresses, moisture ingress, and partial discharge. The research focuses on the effect of temperature and moisture on the effective (complex) permittivity of the cable insulation. Measurements are performed using cylindrical dielectrometry sensors designed to be wrapped around the cable. The lead sheath of the cable is removed so that the sensors can be placed directly in contact with the insulation. From the measurements, the electrical properties of the material as a function of temperature and transient moisture diffusion are found. A theoretical treatment of the interdigital dielectrometry sensors with a cylindrical geometry is presented. Two classes of the geometry are studied. The periodic sensor geometry has electrodes aligned with the cylindrical axis and periodic around the circumference. The z periodic sensor geometry has the electrodes forming rings around the cylinder that are periodic along the cylindrical axis. The material is modeled by concentric rings of homogeneous materials. The electric field solution consists of an infinite summation of Fourier series terms. In finding the field solution and as a consequence of it...

The Women's Technology Program : EECS outreach for high school students; WTP : electrical engineering and computer science outreach for high school students

Ricket, Douglas J. (Douglas James), 1979-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 53 leaves; 608271 bytes; 608026 bytes; application/pdf; application/pdf
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by Douglas J. Ricket.; Thesis (M.Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2002.; Includes bibliographical references (leaves 47-48).; This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.

Improved seed-based MR and CT image registration for prostate brachytherapy; Improved seed-based magnetic resonance and computer tomography image registration for prostate brachytherapy

Kim, Elizabeth S. (Elizabeth Seon-wha), 1979-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 76 p.; 4267003 bytes; 4274963 bytes; application/pdf; application/pdf
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Prostate cancer's high incidence and high survivability motivate its treatment using tightly focused radiation therapy. Brachytherapy treatment, the implantation of radioactive seeds into the prostate, is increasing in popularity, spurred by advances in medical imaging techniques for prostate visualization. Successful brachytherapy requires precise positioning of implant seeds within the pelvic anatomy. Following implantation, precise localization of individual seeds is required to evaluate treatment, but this remains an open challenge. This thesis addresses the seed localization problem with contributions for improving seed-based registration of MR and CT post-implant images. A model for non-rigid, affine prostate motion is presented and demonstrated to improve on current techniques of rigid registration. Also, an evaluation of the benefit of using multiple, rather than a few, seeds is presented, along with a scheme for validating registrations using manually detected seeds in MR and CT volumes. Finally, a scheme for automatic seed-based MR and CT registration by aligning all seeds is suggested, with supporting algorithms for CT seed-finding and unmatched feature registration. A call for an MR seed-finder is issued, for this is the final component needed to achieve automatic and complete seed-based MR and CT registration.; by Elizabeth S. Kim.; Thesis (M. Eng.)--Massachusetts Institute of Technology...