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Electrical Engineering and Computer Sciences - Master's degree

Mostrando recursos 1 - 20 de 6.079

  1. Privatizing the Saudi electricity sector

    Alhumaid, Mohammed S. (Mohammed Saud)
    Electricity demand in Saudi Arabia has been growing rapidly with an average peak demand growth rate of 6% over the past decade. Currently, the structure of the electricity industry is based on a monopoly framework dominated by a government owned utility company (Saudi Electric Company (SEC)). Furthermore, electricity prices in KSA are heavily subsidized and as a result, SEC relies heavily on government support through grants and soft loans to finance expansion projects to meet growing demand. In order to alleviate the financial dependency of the electricity sector on government funding, the system regulator (ECRA) announced major reform plans intended...

  2. Influence maximization over a network : static and dynamic policies

    Ben Chaouch, Zied
    The problem of maximizing the spread of an opinion inside a social network has been investigated extensively during the past decade. The importance of this problem in applications such as marketing has been amplified by the major expansion of online social networks. In this thesis, we study opinion control policies, first under a broad class of deterministic dynamics governing the interactions inside a network, and then under the classical "Voter Model". In the former case, we design a policy that a controller can follow in order to spread an opinion inside a network with the smallest possible cost. In the...

  3. Aggregation for modular robots in the pivoting cube model

    Claici, Sebastian
    In this thesis, we present algorithms for self-aggregation and self-reconfiguration of modular robots in the pivoting cube model. First, we provide generic algorithms for aggregation of robots following integrator dynamics in arbitrary dimensional configuration spaces. We describe solutions to the problem under different assumptions on the capabilities of the robots, and the configuration space in which they travel. We also detail control strategies in cases where the robots are restricted to move on lower dimensional subspaces of the configuration space (such as being restricted to move on a 2D lattice). Second, we consider the problem of finding a distributed strategy...

  4. On the equivalence of sparse statistical problems

    Park, Sung Min, S.M. Massachusetts Institute of Technology
    Sparsity is a widely used and theoretically well understood notion that has allowed inference to be statistically and computationally possible in the high-dimensional setting. Sparse Principal Component Analysis (SPCA) and Sparse Linear Regression (SLR) are two problems that have a wide range of applications and have attracted a tremendous amount of attention in the last two decades as canonical examples of statistical problems in high dimension. A variety of algorithms have been proposed for both SPCA and SLR, but their literature has been disjoint for the most part. We have a fairly good understanding of conditions and regimes under which...

  5. Understanding resilience in large networks

    Sarkar, Tuhin
    This thesis focuses on the analysis of robustness in large interconnected networks. Many real life systems in transportation, economics, finance and social sciences can be represented as networks. The individual constituents, or nodes, of the network may represent vehicles in the case of vehicular platoons, production sectors in the case of economic networks, banks in the case of financial sector, or people in the case of social networks. Due to interconnections between constituents in these networks, a disturbance to any one of the constituents of the network may propagate to other nodes of the network. In any stable network, an...

  6. A microfluidic mucosal airway model to study airway mucosal function and pathogenesis

    Yu, Chia-Chen, S.M. Massachusetts Institute of Technology
    Airway mucus hypersecretion or impaired clearance is one of the key pathophysiological features of airborne infection, allergy and severe respiratory diseases. As foreign particles enter the lungs, the airway becomes inflamed and excessive amount of mucus is generated in response. However, little is known about the role of mucus in regulating the passage of potentially harmful particles. In this thesis, we develop a novel in-vitro microfluidic system which closely models the biophysiological properties of the airway system. Our system accommodates co-current flow of aerosol and mucus and reproduces the key physiology of molecular and particle transport into a mucus barrier....

  7. NOHOST : a new storage architecture for distributed storage systems

    Chung, Chanwoo, S.M. Massachusetts Institute of Technology
    This thesis introduces a new NAND flash-based storage architecture, NOHOST, for distributed storage systems. A conventional flash-based storage system is composed of a number of high-performance x86 Xeon servers, and each server hosts 10 to 30 solid state drives (SSDs) that use NAND flash memory. This setup not only consumes considerable power due to the nature of Xeon processors, but it also occupies a huge physical space compared to small flash drives. By eliminating costly host servers, the suggested architecture uses NOHOST nodes instead, each of which is a low-power embedded system that forms a cluster of distributed key-value store....

  8. Towards high-bandwidth scanning impedance imaging

    Kumar, Rakesh, S.M. Massachusetts Institute of Technology
    Contact-less, three-dimensional scanning is a highly important field for the semiconductor industry. By using a system of high-bandwidth impedance sensors and drive electronics, the physical constituents of ICs such as buried/surface dielectrics, buried/surface conductors and PN junctions could be detected. This thesis takes an initial step toward high-bandwidth electroquasistatic (EQS) imaging by exploring the use of high-frequency imaging. When combined with impedance sensors having a high spatial density, it could be possible to develop a very-high-bandwidth scanning imaging system. The system explored here uses a capacitively-coupled electrode array in order to distinguish various features such as a dielectric layer or...

  9. Compilation using correct-by-construction program synthesis

    Pit-Claudel, Clément
    Extracting and compiling certified programs may introduce bugs in otherwise proven-correct code, reducing the extent of the guarantees that proof assistants and correct-by-construction program-derivation frameworks provide. We explore a novel approach to extracting and compiling embedded domain-specific languages developed in a proof assistant (Coq), showing how it allows us to extend correctness guarantees all the way down to a verification-aware assembly language. Our core idea is to phrase compilation of shallowly embedded programs to a lower-level deeply embedded language as a synthesis problem, solved using simple proof-search techniques. This technique is extensible (support for individual language constructs is provided by...

  10. Platform for spatial molecular data

    Dasari, Vivek
    I designed and implemented a comprehensive platform for storing, analyzing, visualizing, and interacting with spatial molecular data. With the advent of high throughput in situ sequencing methods, such as fluorescent in situ sequencing (FISSEQ), the need for a platform to organize spatial molecular data has become paramount. The platform is divided into seven services: raw data handling, a spatial coordinate system, an analysis service, an image service, a molecular data service, a spatial data service and a visualization service. Together, these services compose a modular system for organizing the next generation of spatial molecular data.

  11. Ingestible electronics without batteries : power and communication for gastroresident devices

    Abid, Abubakar
    In this thesis, I introduce a novel ingestible electronic device designed to reside inside the stomach for weeks or longer with both wireless communication and wireless powering capabilities. The device is powered by a transmitter outside of the body via wireless power transfer through 5 to 6 cm of tissue, while keeping under specific absorption of radiation limits. Electromagnetic theory and microwave simulations identified the optimal region of operation for transmitting power through tissue as around 1 GHz. Small loop antennas fabricated to fit onto a circuit board the size of a pill capsule exhibited power transfer efficiencies of around...

  12. A nanofabricated amplitude-division electron interferometer in a transmission electron microscope

    Agarwal, Akshay
    Wavefront-division electron interferometry with the electron biprism has enabled many applications such as electron holography, exit-wave reconstruction, and demonstration of the Aharonov-Bohm effect. However, wavefront-division interferometry is limited by the requirement of high source coherence. Amplitude-division electron interferometers, first demonstrated by Marton and co-workers in 1954, can overcome this limitation. The implementation of these interferometers is hindered by the precise rotational and translational alignment required. This thesis develops a self-aligned, monolithic electron interferometer consisting of two 45 nm thick silicon layers separated by 20 gm and fabricated from a single crystal silicon cantilever on a transmission electron microscope grid by...

  13. State-space multitaper spectrogram algorithms : theory and applications

    Behr, Michael K
    I present the state-space multitaper approach for analyzing non-stationary time series. Nonstationary time series are commonly divided into small time windows for analysis, but existing methods lose predictive power by analyzing each window independently, even though nearby windows have similar spectral properties. The state-space multitaper algorithm combines two approaches for spectral analysis: the state-space approach models the relations between nearby windows, and the multitaper approach balances a bias-variance tradeoff inherent in Fourier analysis of finite interval data. I illustrate an application of the algorithm to real-time anesthesia monitoring, which could prevent traumatic cases of intraoperative awareness. I discuss issues including...

  14. The data science machine : emulating human intelligence in data science endeavors

    Kanter, Max (James Max)
    Data scientists are responsible for many tasks in the data analysis process including formulating the question, generating features, building a model, and disseminating the results. The Data Science Machine is a automated system that emulates a human data scientist's ability to generate predictive models from raw data. In this thesis, we propose the Deep Feature Synthesis algorithm for automatically generating features for relational datasets. We implement this algorithm and test it on 3 data science competitions that have participation from nearly 1000 data science enthusiasts. In 2 of the 3 competitions we beat a majority of competitors, and in the...

  15. Intrinsic cytometry based on computational microscopy

    Apichitsopa, Nicha
    With the goal of understanding cells, we propose to study the intrinsic properties of individual cells by combining visual observation from large field-of-view computational microscopy with separation of cells via an integrated label-free microfluidic platform. This intrinsic cytometry will benefit from the parallel and gentle separation of label-free cells via a microfluidic platform and parallel tracking of multiple cells via a large field-of view microscopy in contrast to the gold standard, flow cytometry, which is able to rapidly and singly identify multiple cell properties via scattering of external fluorescent cell markers. In this thesis, a prototype of this integrated platform...

  16. Development of cochlear models with high computational efficiency by using spatial and parametric transformations

    Alkhairy, Samiya Ashraf
    Purpose: Our goal is to develop methods to improve the efficiency of computational models of the cochlea for applications that require the solution accurately only within a basal region of interest, specifically by decreasing the number of spatial sections needed for simulation of the problem with good accuracy. Approach: We design algebraic spatial and parametric transformations to computational models of the cochlea that are applied after the region of interest and allow for spatial preservation (spatial causality in the case study model), driven by the naturally absorptive characteristics of the cochlea. Objectives: The goal is to design, characterize and develop...

  17. Deployment of a next generation networking protocol

    Mercer, Logan (Logan James McClure)
    This thesis presents experimental verification of the performance of Group Centric Networking (GCN), a next generation networking protocol developed for robust and scalable communications in lossy networks where users are localized to geographic areas, such as military tactical networks. In previous work, initial simulations in NS3 showed that GCN offers high delivery with low network overhead in the presence of high packet loss and high mobility. We extend this prior work to verify GCN's performance in actual over-the-air experimentation. In the experiments, we deployed GCN on a 90-node Android phone test bed that was distributed across an office building, allowing...

  18. Design of optoelectronic activation, local memory and weighting circuits for Compact Integrated Optoelectronic Neural (COIN) Co-processor

    Tadele, Wegene Haile
    The Compact Integrated Optoelectronic Neural (COIN) Co-processor, a prototype of artificial neural network implemented in hybrid optics and optoelectronic hardware, aims to implement a multi-layer neural network algorithm by performing parallel and efficient neural computations. In this thesis, we design and implement optoelectronic thresholding (activation), weighting and memory circuits for the COIN processor. The first version involved the design of fixed thresholding and weighting functions. The second version incorporated a local capacitive memory element as well as variable weighting schemes. The third version introduces an additional flexibility for variable thresholding by changing the bias voltages of control transistors. A 9x9...

  19. A fast analog controller for a unity power factor AC/DC converter

    Eissa, Mohamed O. (Mohamed Omer)
    by Mohamed O. Eissa.

  20. Failure detection in transformers using vibrational analysis

    Lavalle, Juan Carlos
    by Juan Carlos Lavalle.

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