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Dynamic Range Limitations Of Low-Noise Microwave Transistors At Cryogenic Temperatures, Ahmet Hakan Coskun 2017 University of Massachusetts Amherst

Dynamic Range Limitations Of Low-Noise Microwave Transistors At Cryogenic Temperatures, Ahmet Hakan Coskun

Doctoral Dissertations

Dynamic range is an important metric that specifies the limits of input signal amplitude for the ideal operation of a given receiver. The low end of dynamic range is defined by the noise floor whereas the upper limit is determined by large-signal distortion. While dynamic range can be predicted in the temperature range where compact transistor models are valid, the lack of large-signal models at temperatures below -55 C prevents the prediction and optimization of dynamic range for applications that require cryogenic cooling. For decades, the main goal concerning the performance of these applications was lowering the noise floor of ...


Smart Underground Antenna Arrays: A Soil Moisture Adaptive Beamforming Approach, Abdul Salam, Mehmet C. Vuran 2017 University of Nebraska at Lincoln

Smart Underground Antenna Arrays: A Soil Moisture Adaptive Beamforming Approach, Abdul Salam, Mehmet C. Vuran

CSE Technical reports

In this paper, a novel framework for underground beamforming using adaptive antenna arrays is presented. Based on the analysis of propagation in wireless underground channel, a theoretical model is developed which uses soil moisture information and feedback mechanism to improve performance wireless underground communications. Array element in soil has been analyzed empirically and impacts of soil type and soil moisture on return loss and resonant frequency are investigated. Beam patterns are investigated to communicate with both underground and above ground devices. Depending on the incident angle, refraction from soil-air interface has the adverse effects in the UG communications. It is ...


Development Of Microgrid Test Bed For Testing Energy Management System, Shaili Nepal 2017 South Dakota State University

Development Of Microgrid Test Bed For Testing Energy Management System, Shaili Nepal

Theses and Dissertations

Today the world population has reached 7.5 billion, and this number is expected to grow at the rate of 1.13% every year [1]. With this increase in population, the total demand for electricity has also increased. More people means the need for more power: electricity to power homes, schools, industries, hospitals, and so on. In today’s world, where most of the daily activities are dependent on electricity, demand for electricity, therefore, continues to rise. Currently, managing this growing need for electricity is one of the challenges the world is facing. In addition to this, approximately 1.2 ...


Identification, Calculation And Warning Of Horizontal Curves For Low-Volume Two-Lane Roadways Using Smartphone Sensors, Shaohu Zhang 2017 South Dakota State University

Identification, Calculation And Warning Of Horizontal Curves For Low-Volume Two-Lane Roadways Using Smartphone Sensors, Shaohu Zhang

Theses and Dissertations

Smartphones and other portable personal devices that integrate global positioning systems, Bluetooth Low Energy, and advanced computing technologies have become more accessible due to affordable prices, product innovation, and people’s desire to be connected. As more people own these devices, there are greater opportunities for data acquisition in Intelligent Transportation Systems, and for vehicle-to-infrastructure communication. Horizontal curves are a common factor in the number of observed roadway crashes. Identifying locations and geometric characteristics of the horizontal curves plays a critical role in crash prediction and prevention, and timely curve warnings save lives. However, most states in the US face ...


Magneto Inductive Communication System For Underwater Wireless Sensor Networks, Niaz Ahmed 2017 Missouri University of Science and Technology

Magneto Inductive Communication System For Underwater Wireless Sensor Networks, Niaz Ahmed

Doctoral Dissertations

"Underwater wireless sensor networks have found a number of applications in underwater environment monitoring, infrastructure monitoring, military applications and ocean exploration. Among the four possible means of underwater wireless communication, namely acoustic, electromagnetic (EM), magneto-inductive (MI) and optics communication, MI communication enjoys the advantages of being low cost and robust equally in air, water and soil. This dissertation presents design and implementation of a low-power and low-cost MI sensor network node that is suited for long-term deployment of underwater and underground infrastructure monitoring, such as bridge scour and levee scour monitoring. The designed MI sensor node combat the directionality of ...


Variable Input Space Observer For Structural Health Monitoring Of High-Rate Systems, Jonathan Hong, Simon Laflamme, Jacob Dodson 2016 Iowa State University

Variable Input Space Observer For Structural Health Monitoring Of High-Rate Systems, Jonathan Hong, Simon Laflamme, Jacob Dodson

Simon Laflamme

Some engineering systems experiencing high-rate dynamic events, including air bags, debris detection, and active blast protection systems, could benefit from high-rate real-time observers for enhanced performance. However, the task of high-rate state estimation is challenging, in particular for real-time applications where the rate of the observer’s convergence needs to be in the microsecond range. This paper discusses critical challenges in designing highrate observers, and argues that adaptive observers are promising at the task of state estimation, and that they could be applied at high-rates provided the development of strategies to substantially increase their convergence. A novel adaptive observer termed ...


Scenario Generation For Price Forecasting In Restructured Wholesale Power Markets, Qun Zhou, Leigh Tesfatsion, Chen-Ching Liu 2016 Iowa State University

Scenario Generation For Price Forecasting In Restructured Wholesale Power Markets, Qun Zhou, Leigh Tesfatsion, Chen-Ching Liu

Leigh Tesfatsion

Abstract: In current restructured wholesale power markets, the short length of time series for prices makes it difficult to use empirical price data to test existing price forecasting tools and to develop new price forecasting tools. This study therefore proposes a two-stage approach for generating simulated price scenarios based on the available price data. The first stage consists of an Autoregressive Moving Average (ARMA) model for determining scenarios of cleared demands and scheduled generator outages (D&O), and a moment-matching method for reducing the number of D&O scenarios to a practical scale. In the second stage, polynomials are fitted ...


Development Of An Agent-Based Distribution Test Feeder With Smart-Grid Functionality, Pedram Jahangiri, Di Wu, Wanning Li, Dionysios C. Aliprantis, Leigh Tesfatsion 2016 Iowa State University

Development Of An Agent-Based Distribution Test Feeder With Smart-Grid Functionality, Pedram Jahangiri, Di Wu, Wanning Li, Dionysios C. Aliprantis, Leigh Tesfatsion

Leigh Tesfatsion

This paper reports on the development of an agent-based distribution test feeder with smart-grid functionality. The test feeder is based on an actual distribution feeder with various additional features incorporated, including rooftop photovoltaic generation and price-responsive loads (e.g., plug-in electric vehicles and intelligent air-conditioning systems). This work aims to enable the integrated study of wholesale electric power markets coupled with detailed representations of the retail-side distribution systems.


Iso Net Surplus Collection And Allocation In Wholesale Power Markets Under Lmp, Hongyan Li, Leigh Tesfatsion 2016 ABB Inc.

Iso Net Surplus Collection And Allocation In Wholesale Power Markets Under Lmp, Hongyan Li, Leigh Tesfatsion

Leigh Tesfatsion

This study uses five-bus and 30-bus test cases to explore ISO net surplus (congestion rent) collections and allocations in wholesale power markets with grid congestion managed by locational marginal prices (LMPs). Price-sensitivity of demand and generator learning capabilities are taken as experimental treatment factors. A key finding is that conditions resulting in greater generator capacity withholding, hence higher and more volatile LMPs, also result in greater ISO net surplus collections that can be substantial in size. A key conclusion is that ISO net surplus collections should be used pro-actively to mitigate the conditions encouraging generator capacity withholding and hence high ...


Development Of Open Source Software For Power Market Research: The Ames Test Bed, Hongyan Li, Leigh Tesfatsion 2016 Iowa State University

Development Of Open Source Software For Power Market Research: The Ames Test Bed, Hongyan Li, Leigh Tesfatsion

Leigh Tesfatsion

Open source software (OSS) expresses the idea that developers should be able to license the publication of their software in a manner permitting anyone to freely use, modify and distribute the software. Today OSS is widely used in the software industry: for example, for language development tools (eg, NetBeans for Java), office document processors (eg, OpenOffice) and operating systems (eg, Linux, OpenSolaris).Yet OSS has been slow to penetrate the power industry; heavy reliance is still placed on closed-source commercial software packages. Open source software tends to be used for specialized purposes (eg, circuit design) rather than for the general-purpose ...


Integrated Retail And Wholesale Power System Operation With Smart-Grid Functionality, Dionysios C. Aliprantis, Scott Penick, Leigh Tesfatsion 2016 Iowa State University

Integrated Retail And Wholesale Power System Operation With Smart-Grid Functionality, Dionysios C. Aliprantis, Scott Penick, Leigh Tesfatsion

Leigh Tesfatsion

Our research team is developing an agent-based test bed for the integrated study of retail and wholesale power markets operating over transmission and distribution networks with smart-grid functionality. This test bed seams together two existing test beds, the AMES Wholesale Power Market Test Bed and the GridLAB-D distribution platform. As a first step, we have designed an integrated retail/wholesale market module specifically based on the ERCOT (Texas) energy region, and we are using simplified versions of this module to study potential retail consumer response to real-time-pricing contracts supported by advanced metering. This study reports on the latter work.


Intelligent Residential Air-Conditioning System With Smart-Grid Functionality, Auswin George Thomas, Pedram Jahangiri, Di Wu, Chengrui Cai, Huan Zhao, Dioysios C. Aliprantis, Leigh Tesfatsion 2016 Iowa State University

Intelligent Residential Air-Conditioning System With Smart-Grid Functionality, Auswin George Thomas, Pedram Jahangiri, Di Wu, Chengrui Cai, Huan Zhao, Dioysios C. Aliprantis, Leigh Tesfatsion

Leigh Tesfatsion

This paper sets forth a novel intelligent residential air-conditioning (A/C) system controller that has smart grid functionality. The qualifier “intelligent” means the A/C system has advanced computational capabilities and uses an array of environmental and occupancy parameters in order to provide optimal intertemporal comfort/cost trade-offs for the resident, conditional on anticipated retail energy prices. The term “smart-grid functionality” means that retail energy prices can depend on wholesale energy prices. Simulation studies are used to demonstrate the capabilities of the proposed A/C system controller.


Capacity Withholding In Restructured Wholesale Power Markets: An Agent-Based Test Bed Study, Hongyan Li, Leigh Tesfatsion 2016 Iowa State University

Capacity Withholding In Restructured Wholesale Power Markets: An Agent-Based Test Bed Study, Hongyan Li, Leigh Tesfatsion

Leigh Tesfatsion

This study uses a dynamic 5-bus test case implemented via the AMES Wholesale Power Market Test Bed to investigate strategic capacity withholding by generation companies (GenCos) in restructured wholesale power markets under systematically varied demand conditions. The strategic behaviors of the GenCos are simulated by means of a stochastic reinforcement learning algorithm motivated by human-subject laboratory experiments. The learning GenCos attempt to improve their earnings over time by strategic selection of their reported supply offers. This strategic selection can involve both physical capacity withholding (reporting of lower-than-true maximum operating capacity) and economic capacity withholding (reporting of higher-than-true marginal costs). We ...


Modelling And Analysis Of Smart Grids For Critical Data Communication, Abdulfattah Noorwali 2016 The University of Western Ontario

Modelling And Analysis Of Smart Grids For Critical Data Communication, Abdulfattah Noorwali

Electronic Thesis and Dissertation Repository

Practical models for the subnetworks of smart grid are presented and analyzed. Critical packet-delay bounds for these subnetworks are determined, with the overall objective of identifying parameters that would help in the design of smart grid with least end-to-end delay.

A single-server non-preemptive queueing model with prioritized critical packets is presented for Home Area Network (HAN). Closed-form expressions for critical packet delay are derived and illustrated as a function of: i) critical packet arrival rate, ii) service rate, iii) utilization factor, and iv) rate of arrival of non-critical packets. Next, wireless HANs using FDMA and TDMA are presented. Upper and ...


Data Logging System For A Synthetic Aperture Radar Unit, Nicholas J. Testin, Philip Davis, Ian Dorell, Alexander Gillespie 2016 Kennesaw State University

Data Logging System For A Synthetic Aperture Radar Unit, Nicholas J. Testin, Philip Davis, Ian Dorell, Alexander Gillespie

Honors College Capstones and Theses

A small, existing radar unit lacked the ability to automatically store the data it was receiving, which made its use clunky and cumbersome. A system was constructed to allow an on-board microprocessor to track distance traveled, and automatically store the data output from the radar unit to a portable memory unit for later data processing. Distance traveled is determined using a specially designed mobile cart, which electronically converts the rotation of a wheel into an electrical signal while also providing stability for taking accurate radar measurements. The output data from the radar unit is stored as a properly-formatted sound file ...


A Quantitative Measure Of Mono-Componentness For Time-Frequency Analysis, Austin P. Albright 2016 University of Tennessee, Knoxville

A Quantitative Measure Of Mono-Componentness For Time-Frequency Analysis, Austin P. Albright

Doctoral Dissertations

Joint time-frequency (TF) analysis is an ideal method for analyzing non-stationary signals, but is challenging to use leading to it often being neglected. The exceptions being the short-time Fourier transform (STFT) and spectrogram. Even then, the inability to have simultaneously high time and frequency resolution is a frustrating issue with the STFT and spectrogram. However, there is a family of joint TF analysis techniques that do have simultaneously high time and frequency resolution – the quadratic TF distribution (QTFD) family. Unfortunately, QTFDs are often more troublesome than beneficial. The issue is interference/cross-terms that causes these methods to become so difficult ...


Single Carrier Frequency Domain Equalization And Energy Efficiency Optimization For Mimo Cognitive Radio., Xiaohui Zhang 2016 University of Louisville

Single Carrier Frequency Domain Equalization And Energy Efficiency Optimization For Mimo Cognitive Radio., Xiaohui Zhang

Electronic Theses and Dissertations

This dissertation studies two separate topics in wireless communication systems. One topic focuses on the Single Carrier Frequency Domain Equalization (SC-FDE), which is a promising technique to mitigate the multipath effect in the broadband wireless communication. Another topic targets on the energy efficiency optimization in a multiple input multiple output (MIMO) cognitive radio network. For SC-FDE, the conventional linear receivers suffer from the noise amplification in deep fading channel. To overcome this, a fractional spaced frequency domain (FSFD) receiver based on frequency domain oversampling (FDO) is proposed for SC-FDE to improve the performance of the linear receiver under deep fading ...


Design And Implementation Of Reconfigurable Patch Antennas For Wireless Communications, Fei He 2016 University of Nebraska-Lincoln

Design And Implementation Of Reconfigurable Patch Antennas For Wireless Communications, Fei He

Theses, Dissertations, and Student Research from Electrical & Computer Engineering

Reconfigurable patch antennas have drawn a lot of research interest for future wireless communication systems due to their ability to adapt to changes of environmental conditions or system requirements. The features of reconfigurable patch antennas, such as enhanced bandwidths, operating frequencies, polarizations, radiation patterns, etc., enables accommodation of multiple wireless services.

The major objective of this study was to design, fabricate and test two kinds of novel reconfigurable antennas: a dual-frequency antenna array with multiple pattern reconfigurabilities, and a pattern and frequency reconfigurable Yagi-Uda patch antenna. Comprehensive parametric studies were carried out to determine how to design these proposed patch ...


Improved Localization Algorithms In Indoor Wireless Environment, Fei Long 2016 The University of Western Ontario

Improved Localization Algorithms In Indoor Wireless Environment, Fei Long

Electronic Thesis and Dissertation Repository

Localization has been considered as an important precondition for the location-dependent applications such as mobile tracking and navigation.To obtain specific location information, we usually make use of Global Positioning System(GPS), which is the most common plat- form to acquire localization information in outdoor environments. When targets are in indoor environment, however, the GPS signal is usually blocked, so we also consider other assisted positioning techniques in order to obtain accurate position of targets. In this thesis, three different schemes in indoor environment are proposed to minimize localization error by placing refer- ence nodes in optimum locations, combining the ...


Channel And Noise Variance Estimation For Future 5g Cellular Networks, Jorge Iscar Vergara 2016 Florida International University

Channel And Noise Variance Estimation For Future 5g Cellular Networks, Jorge Iscar Vergara

FIU Electronic Theses and Dissertations

Future fifth generation (5G) cellular networks have to cope with the expected ten-fold increase in mobile data traffic between 2015 and 2021. To achieve this goal, new technologies are being considered, including massive multiple-input multiple-output (MIMO) systems and millimeter-wave (mmWave) communications. Massive MIMO involves the use of large antenna array sizes at the base station, while mmWave communications employ frequencies between 30 and 300 GHz. In this thesis we study the impact of these technologies on the performance of channel estimators.

Our results show that the characteristics of the propagation channel at mmWave frequencies improve the channel estimation performance in ...


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