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- Title
- AN ENERGY EFFICIENT ROUTING PROTOCOL FOR WIRELESS SENSOR NETWORKS
- Creator
- Lara, Aurobinda
- Date
- 2012-04-27, 2012-05
- Description
-
Wireless distributed microsensor systems will enable the reliable monitoring of a variety of environments for both civil and military...
Show moreWireless distributed microsensor systems will enable the reliable monitoring of a variety of environments for both civil and military applications. A wireless sensor network consists of nodes that can communicate with each other via wireless links. One way to support efficient communication between sensors is to organize the network into several groups, called clusters, with each cluster electing one node as the head of cluster. Energy efficiency is of great importance for the wireless sensor network (WSN). A popular way to save energy is to construct clusters for data aggregation and forwarding. In this thesis a distributed cluster algorithm is studied to improve the energy consumption efficiency. It was observed that the cluster head has to lie within the transmission range of the base station (sink node) and the distance between cluster head and base station is critical for the energy consumption performance, we proposed a pseudo-cluster and virtual hierarchical clustering scheme (PC-LEACH), which considers the power level of the non-cluster head nodes and the residual energy level during the cluster head selection stage. Consequently we could better balance the chance of being cluster head for all nodes. Simulation results show that the scheme is able to result in longer network lifetime than the well-known protocol LEACH.
M.S. in Electrical Engineering, May 2012
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- Title
- HIGH PERFORMANCE, HIGH STABILITY AND LOW POWER SRAM DESIGN BY USING CARBON NANOTUBE FIELD EFFECT TRANSISTORS
- Creator
- Wang, Wei
- Date
- 2012-07-07, 2012-07
- Description
-
As the feature size of silicon semiconductor devices scales down to nanometer range, planar bulk CMOS design and fabrication encounter...
Show moreAs the feature size of silicon semiconductor devices scales down to nanometer range, planar bulk CMOS design and fabrication encounter significant challenges. This situation is exacerbated when it comes to SRAM, as SRAM takes a large part of power consumption and area overhead in modern VLSI processor designs. To achieve higher performance, stability and lower power consumption, carbon nanotube (CNT) has been introduced to SRAM design as an alternative material. The semiconducting single-walled CNTs are promising candidates for the channel material of CMOS devices because of two advantages over the other semiconductor materials: high ON current, leading to high speed and low OFF current, leading to less leakage power. In this research work, characterizing work of technology parameters for 6T carbon nanotube field effect transistor (CNFET) SRAM cell is performed for basic understanding of the relationship between SRAM delay/power and CNFET technology parameters. Stability issue is studied by investigating the diameter and transistor ratio impacts on the SRAM static noise margin (SNM). A stability-optimized 6T CNFET SRAM cell achieves 38.88% reading delay reduction, 21.61% writing delay reduction, 85.65% reading power reduction, 5.88% writing power reduction, 97.80% leakage power reduction, 41.41% SNM increment, 91.23% reading power-delay product (PDP) reduction and 26.23% writing PDP reduction, compared with conventional silicon MOSFET SRAM cell. To mitigate major CNT imperfection impacts on CNFET circuits, a misalignment immune SRAM design method is proposed to eliminate CNT misalignment problem by using etching region defined in circuit layout; and a diameter variation sensing and compensating system is designed to mitigate the negative impacts of CNT diameter variation on SRAM delay and power consumption. A hybrid silicon/CNT 4T SRAM cell design is proposed for low-power high-density cache application, which is better than conventionally used 6T SRAM in terms of power consumption and circuit area. Finally, a design flow of high performance, high stability and low power SRAM is summarized.
Ph.D. in Electrical Engineering, July 2012
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- Title
- Test of a new type of storage cell
- Creator
- Allyn, A. J., Torrance, R. S.
- Date
- 2009, 1906
- Publisher
- Armour Institute of Technology
- Description
-
http://www.archive.org/details/testofnewtypeofs00ally
Thesis (B.S.)--Armour Institute of Technology
- Title
- SEARCHING ENCRYPTED CLOUD DATA
- Creator
- Urs, Karthik Mahendra Raje
- Date
- 2011-05-04, 2011-05
- Description
-
The major setback of the cloud is its inability to induce strong trust in its users. For us, the users of the cloud, to be sure of the...
Show moreThe major setback of the cloud is its inability to induce strong trust in its users. For us, the users of the cloud, to be sure of the security of the data from other users, we have to trust cloud. In most of the cases, say if the data were to be hosted on Microsoft’s servers, we can trust Microsoft in its policies to prevent unauthorized access to it from other users (via hacking). But, the issue that is haunting the cloud is this - ”How can we be sure that our data is safe from Cloud service providers themselves?” The most intuitive solution for the cloud service provider to gain trust is to insist we encrypt our data. That is an irrefutable act of honesty from the cloud. But this has some obvious setbacks, few of which would negate the very advantages of cloud. One such issue that dictates the scope of this thesis is this - Typical cryptographic algorithms are not amenable to search. Now, if we were to implement a search engine on cloud (which has the data encrypted), the native search techniques have to be extended on to the cryptographic domain so that the cloud can perform the tasks of a search engine. This thesis explores the solutions to the above mentioned problem of searching over encrypted data, specifically using a secure pre-processed index approach. Though significant ideas have been proposed in the area, there is no concrete implementation to analyze if it can be used in the industrial setting. The main goal of the thesis is to implement a system which supports a variety of searching techniques. We make use of Amazon EC2 and test out the designed systems to evaluate how feasible they are for immediate consumption by the industry.
M.S. in Computer Engineering, May 2011
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- Title
- The synchronous motor
- Creator
- Sleezer, Frank W., Williams, Wallace, Kelkenney, Artemas A.
- Date
- 2009, 1907
- Publisher
- Armour Institute of Technology
- Description
-
http://www.archive.org/details/synchronousmotor00slee
Thesis (B.S.)--Armour Institute of Technology; Bibliography: leaves 35-37
- Title
- Test and report of a modern ice plant
- Creator
- Heim, Karl, Fitch, Joseph E, Jones, Charles H, Hirschfeld, George
- Date
- 2009, 1909
- Publisher
- Armour Institute of Technology
- Description
-
http://www.archive.org/details/testreportofmode00heim
Thesis (B.S.)--Armour Institute of Technology
- Title
- DEVELOPMENT OF AN EMBEDDED CONTROLLER FOR TWO QUADRANT OPERATION OF BLDC MOTORS IN AUTOMOTIVE APPLICATIONS
- Creator
- Liu, Yizhe
- Date
- 2011-07-06, 2011-07
- Description
-
Due to growing concerns over the availability of non-renewable petroleum products and the increasing emphasis on protecting our environment...
Show moreDue to growing concerns over the availability of non-renewable petroleum products and the increasing emphasis on protecting our environment from green house gas emissions, plug-in hybrid electric vehicle and hybrid electric vehicles have been gaining increasing popularity over recent years. This has led to the design of advanced drive systems using different electric motors such as BLDC, PMSM, IM and SRM. An electric motor/generator requires controller that not only has a strong I/O control function, but also high speed signal processing ability for realizing real time control. Therefore, a DSP (Digital Signal Processors), which integrates flexible multiple PWM signal generator, high speed high precision ADC and encoder interface for motor speed and position feedback, is considered as one of the strongest controllers for electric motor control. Owing to a growing emphasis on identification, interference, and communication of security services of drive train in intelligent PHEVs and HEVs, a DSP can also be used to identify and isolate security issues in the integrity of the drive train in PHEVs and EVs. This thesis has two main contributions: a) it focuses on the development of an embedded controller using TMS320LF2812 DSP to realize two quadrant control of the BLDC; and b) it develops an automotive test bench to identify and investigate some potential security issues using the embedded controller’s eCAN communication function.
M.S. in Electrical Engineering, May 2011
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- Title
- DYNAMIC SIMULATION AND LOAD MODELING FOR VOLTAGE RECOVERY STUDIES WITH THREE-PHASE AND SINGLE-PHASE INDUCTION MOTORS
- Creator
- Zhang, Jingpei
- Date
- 2017, 2017-05
- Description
-
Transient stability topics have been popular in modern power systems and time domain simulation provides an efficient evaluation for...
Show moreTransient stability topics have been popular in modern power systems and time domain simulation provides an efficient evaluation for correlative studies. So far, we have been working on developing advanced time-domain simulator TS3ph, which implements simulation on electromechanical level but with three-phase completed network model to enable unbalanced modeling and simulation. In this paper, modeling and development work of TS3ph are being introduced. Positive-sequence equivalent and three-phase based models, including static var compensator, governor and three-phase induction motor models, are built and validated to evaluate their dynamic behaviors in transient state. Moreover, research work on single phase induction motor model development, including important motor behaviors such as motor stalling, is also introduced in this paper for voltage collapse and recovery study. This is indeed the first time to apply such model on electromechanical simulator as well.
M.S. in Electrical Engineering, May 2017
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- Title
- SYSTEM-ON-CHIP ARCHITECTURES FOR SIGNAL PROCESSING AND COMMUNICAnONS
- Creator
- Niu, Sufeng
- Date
- 2012-04-30, 2012-05
- Description
-
System-On-Chip (SOC) is one of the most popular Computer Aided Design (CAD) methodologies in electronic system design. In this research, SOC...
Show moreSystem-On-Chip (SOC) is one of the most popular Computer Aided Design (CAD) methodologies in electronic system design. In this research, SOC design is investigated in two different types of applications: i) low cost and power efficient applications; and ii) high performance computing applications. To explore low cost and power efficient design, a microcontroller based wireless medical system is investigated. Two wireless communication protocols for medical applications and patient monitoring are analyzed. In addition, the ZigBee stack developed by TI and a medical amplifier are discussed. For high performance SOC applications, implementations of several matrix operations are examined. An improved fixed-point hardware design of QR decomposition is introduced and optimized for Xilinx FPGAs. A Givens Rotation algorithm is implemented using a folded systolic array and the CORDIC algorithm. This approach is highly suitable for high-speed FPGAs or ASIC designs. It is found that the Xilinx XC5VLX110T FPGA is capable of running the QR decomposition at 246MHz.
M.S. in Electrical Engineering, May 2012
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- Title
- OPTIMAL BIDDING STRATEGY FOR HYDRO UNIT
- Creator
- Zhu, Renchen
- Date
- 2013-04-30, 2013-05
- Description
-
The bidding price for the renewable energy is very different from some traditional energy, like gas, coal and so on, because when we produced...
Show moreThe bidding price for the renewable energy is very different from some traditional energy, like gas, coal and so on, because when we produced the renewable energy, the only cost is the generator unit cost, for example, wind power, water power and so on. People never need to pay the fuel price for the solar, water or wind. So here come one question how can we decide the energy price for these power. As we all know, the bidding price decided the profit for the generating company. Nowadays, more and more researches have been done in this field for every company want a good price to earn the highest profit. But for the renewable energy, they are different from the traditional energy which price is determined by the fuel price. So how to decide the bidding price of the renewable energy will be a good topic and question for us. To solve this problem, I will try to use an idea called minimum the imbalance in order to maximum the profit for those owners. This idea first has been applied in the wind unit. For my thesis, I will apply this idea to the hydro unit both with the storage and without storage. For each part, I will use some data to test. By these testing, the result will show this bidding strategy will be better.
M.S. in Electrical Engineering, May 2013
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- Title
- PARAMETRIC IMAGE ESTIMATION IN ANALYZER-BASED PHASE CONTRAST IMAGING
- Creator
- Caudevilla, Oriol
- Date
- 2014, 2014-07
- Description
-
Since the discovery of X-rays, by W.E. Roentgen in 1895, absorption-contrast imaging has been widely used in medical diagnostic, for example:...
Show moreSince the discovery of X-rays, by W.E. Roentgen in 1895, absorption-contrast imaging has been widely used in medical diagnostic, for example: mammography, chest X-ray, angiography etc. Over the last 25 years many researchers have shown that phase-contrast X-ray imaging is capable of obtaining a better contrast then classical absorption-contrast imaging. This is especially true in soft tissue imaging like mammography or at higher Xrays energies. During the past five years a significant effort has made in development of a tabletop analyzer-based phase-contrast system. In this system a perfect crystal is used to generate a quasi-monochromatic beam, which after interacting with an object is analyzed by a second perfect crystal called analyzer. The need of quasi-monochromatic beam and the low brilliance of conventional X-ray sources (CXS) has been the major limiting factor for tabletop systems. The work presents in this thesis aims to develop novel reconstruction methods for tabletop analyzer-based phase-contrast imaging (ABI) systems. The presented reconstruction methods goal is to minimize the impact of CXS low brilliance by utilizing phase-contrast image formation model and maximum or maximum-a-posteriori Poisson likelihood approach. Finally, a fast-convergent conjugate gradient optimization algorithm has been derived specifically for Poisson likelihood function maximization.
M.S. in Electrical Engineering, July 2014
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- Title
- POWER ANALYSIS AND CONTROL OPTIMIZATION OF A HIGH GAIN RESONANT DC-DC CONVERTER
- Creator
- Wu, Haowen
- Date
- 2017, 2017-05
- Description
-
Applications of DC-DC converter require a high power, high efficiency performance, especially for automotive applications and renewable energy...
Show moreApplications of DC-DC converter require a high power, high efficiency performance, especially for automotive applications and renewable energy applications. A desired converter should have a fast response, stable output in different conditions. This thesis studies a novel high gain DC-DC resonant converter and its control. Based on the circuit analysis and operation evaluation, feed-forward and feedback control methods are proposed in order to achieve stability under variety of changes. Moreover, circuit topology is investigated in response to the efficiency improvement. Simulations in PSIM, PLECS and MATLAB Simulink have been carried out to validate the controller design and topology development. The simulation results are in consistence to the theoretical analysis. The overall high efficiency at nominal operating point is further increased.
M.S. in Electrical Engineering, May 2017
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- Title
- NOVEL FAULT DIAGNOSTIC TECHNIQUE AND UNIVERSAL SENSOR FOR PERMANENT MAGNET ELECTRIC MACHINES USING SEARCH COILS
- Creator
- Da, Yao
- Date
- 2012-04-23, 2012-05
- Description
-
Over the past decade, permanent magnet synchronous machines (PMSMs) have gained significant popularity in industry, such as wind turbines and...
Show moreOver the past decade, permanent magnet synchronous machines (PMSMs) have gained significant popularity in industry, such as wind turbines and electric vehicles, owing to their high efficiency, high output power to volume ratio, and high torque to current ratio. In these mission critical applications, an unexpected fault or failure of the machine could lead to very high repair or replacement cost, or even catastrophic system failure. Therefore a robust and reliable health monitoring and fault diagnostic approach is desired, which could help in scheduling preventive maintenance to lengthen their lifespan and avoid machine failure. This dissertation presents a novel multi-faults diagnostic approach using search coils. These search coils are wound around armature teeth, so they typically need to be installed during manufacturing. But its immunity to high frequency harmonics makes it suitable for inverter/rectifier fed motors or generators, such as wind turbines and automotive systems. In addition, this method does not require the knowledge of proprietary constructional details of the machine. Since the electromagnetic flux is directly measured in this method, it provides much more information than any other scheme: the direction of eccentricity and the location of shorted windings. Furthermore, this method is also capable of evaluating the severity of each fault, which is of significant importance in mission critical applications such as automotive, aerospace and military applications. In addition to these uses, the search coils can be used as a universal sensor to estimate phase current or rotor position, which are critical information in a PMSM close-loop control, which allow it to work as a backup sensor for fault tolerant operation. The proposed fault detection scheme and universal sensor concept have been tested under several scenarios with Finite Element Analysis and experimentally validated.
Ph.D. in Electrical Engineering, May 2012
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- Title
- A system of multiplex telephony by the use of vacuum tubes
- Creator
- Arnold, E. H., Throop, A. R.
- Date
- 2009, 1919
- Publisher
- Armour Institute of Technology
- Description
-
http://www.archive.org/details/systemofmultiple00arno
Thesis (B.S.)--Armour Institute of Technology; Bibliography: leaves 44-45
- Title
- Transients on transmission lines and modern protective devices
- Creator
- Muelleman, Joseph P., Smely, James
- Date
- 2009, 1920
- Publisher
- Armour Institute of Technology
- Description
-
http://www.archive.org/details/transientsontran00muel
Thesis (B.S.)--Armour Institute of Technology
- Title
- FINFET BASED STANDARD CELL LIBRARY CHARACTERIZATION
- Creator
- Yuan, Yu
- Date
- 2015, 2015-07
- Description
-
In this work, four standard cell libraries based on FinFET technology have been characterized and implemented. The first library uses the BSIM...
Show moreIn this work, four standard cell libraries based on FinFET technology have been characterized and implemented. The first library uses the BSIM-CMG and PTM-MG models, which represents the common multi-gate devices. Two libraries are based on the BSIM-IMG model, operating in short-gate (corresponding to low-Vt) mode and lowpower (corresponding to high-Vt) mode separately. Synthesis and simulation of BSIMCMG based library is presented and compared to the conventional 45nm CMOS library, FreePDK45. The results show acceptable accuracy of the library based on BSIM-CMG model. For the libraries based on BSIM-IMG model, Short-Gate (SG) mode, Low-Power (LP) mode and the mixed-mode (combining both SG and LP modes) have been analyzed. The results proved that the low-power independent multi-gate FinFET can be used for leakage power reduction, just like the bulk CMOS high-Vt devices. At the end of this work, another library based on CCS model was characterized and verified, which show far better accuracy in terms of both timing and power modeling.
M.S. in Electrical Engineering, July 2015
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- Title
- Some commutation phenomena of direct current machinery
- Creator
- Clark, F. C.
- Date
- 2009, 1905
- Publisher
- Armour Institute of Technology
- Description
-
http://www.archive.org/details/somecommutationp00clar
Thesis (B.S.)--Armour Institute of Technology
- Title
- OPTIMIZATION OF POWER TRENCH MOSFETS FOR HIGH EFFICIENCY SYNCHRONOUS BUCK CONVERTERS
- Creator
- Wang, Wendi
- Date
- 2016, 2016-05
- Description
-
Synchronous buck converter might be one of the most widely used and fabricated circuitry in the world for its favorable trade-off on many...
Show moreSynchronous buck converter might be one of the most widely used and fabricated circuitry in the world for its favorable trade-off on many subjects. However, the ever higher operation frequency has lead to increasing power loss in power switches and imposed new challenge to MOSFET engineering. One promising alternative for the traditionally used trench MOSFET is the shield gate MOSFET. Shield gate MOSFET has superior conduction performance as well as fast switching transient response due to its Reduced Surface Electric Field (RESURF) effect. In recent years, characterization of power MOSFET has developed along with MOSFET technology itself. New Figure of Merits (FOMs) have come into people's sight as they serve as better standards to fully describe MOSFET's overall performance. Being the same case for many other device structures, this new characterizing system also puts advanced requirements to shield gate MOSFET. And one of the most crucial problems is the rather large output capacitance this structure is having. To improve the property of shield gate MOSFET and meet the requirements of new standards, several ways of structure refinement have been proposed in this work. Both shield gate MOSFET and conventional MOSFET rated at 40V have been designed and simulated in the second chapter. The outcome shows that shield gate MOSFET has superior performance in almost every respect except for its large output charge. Then new structure for COSS reduction has been introduced in the following section, with decrement of about 50% in QQS-1 being achieved. Finally, another issue that has been tackled with is the shoot through of synchronous buck converter. Equivalent circuit model for shoot through analysis is built in this section to study the effect of each parasitic element. And a p type pillar added structure has been verified as an effective way to suppress shoot through gate bounce.
M.S. in Electrical Engineering, May 2016
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- Title
- Some features of a modern overhead distributing system
- Creator
- Redman, A. R.
- Date
- 2009, 1916
- Publisher
- Armour Institute of Technology
- Description
-
http://www.archive.org/details/somefeaturesofmo00redm
Thesis (B.S.)--Armour Institute of Technology
- Title
- OPTIMIZATION AND MARKET CLEARING IN THE POWER SYSTEMS WITH HIGH-LEVEL RENEWABLES
- Creator
- Ye, Hongxing
- Date
- 2016, 2016-05
- Description
-
The increasing penetration of renewable energy source (RES), such as wind and solar power generation, in recent years to meet various...
Show moreThe increasing penetration of renewable energy source (RES), such as wind and solar power generation, in recent years to meet various renewable portfolio standards (RPS) has led to more uncertainties in power systems. The RES penetration level is expected to further increase in order to reduce emission and fight climate change. The growing uncertainties caused by RES pose new challenges in power and energy systems. Advanced models and technologies are urgent to provide secure, affordable and clean energy to customers. Security-Constrained Unit Commitment (SCUC) problem is one of the most important tools in the modern power system. It determines the optimal short-term generating planning. The electricity is priced and settled based on its solution. In order to manage the uncertainties caused by renewables, it is urgent to develop new SCUC models and solution approaches. SCUCs considering the uncertainties have become a focus of research in recent years. The proposed optimistic robust SCUC combines the idea of robust optimization and reserve concept in the electricity. The merit of the robust optimization is that its solution can be immunized against any uncertainties. It exactly meets the first priority, reliability, in power system operation. The robust optimization is attractive in theory. However, a solution is robust if and only if the system can survive in the worst case scenario. Hence, the key task is to identify the worst case scenario. Unfortunately, finding the worst case scenario in general is a non-deterministic polynomial-time hard (NP-hard) problem. This will create issue in satisfying the timeliness requirement that the optimal scheduling must be obtained quickly (e.g., within several hours) in the day-ahead electricity markets. This dissertation proposes a fast solution approach to finding the worst case scenario by exploring the special structure in the SCUC problem. This dissertation proposes a new market mechanism for managing uncertain ties caused by high-level RES based on the robust optimization. A new concept, Uncertainty Marginal Price (UMP), is proposed to charge uncertainty sources and to credit flexible sources. For the first time, explicit price signals are provided and utilized to manage any level uncertainties within a robust optimization framework. The proposed mechanism manages uncertainties from both the source side (uncertainty reduction) and resource side (uncertainty accommodation). In short term, it provides incentives for RES operators to improve forecasting accuracy (i.e. to reduce uncertainties) and existing flexible resources (e.g. storage) to participate the uncertainty accommodation. In long term, the proposed mechanism provides price signals for siting new flexible resources (e.g. energy storage) to accommodate uncertainties from increasing RES penetration.
Ph.D. in Electrical Engineering, May 2016
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