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Title: DESIGN AND IMPLEMENTATION OF A POWER ASSISTED DRIVETRAIN FOR A WHEELCHAIR
Creator: Hou, Ruoyu
Date: 2012-04-06, 2012-05
Description: Over the last two decades, the number of people who have difficulty walking and need wheelchairs has been found to be increasing due to an...
Show moreOver the last two decades, the number of people who have difficulty walking and need wheelchairs has been found to be increasing due to an aging population caused by a low birth rate and advances in medical treatment. Based on a recent survey, a power assisted wheelchair is the latest one in the commercial wheelcair market. The power assisted wheelchair offers users an opportunity for physical activity, but it is often too expensive for customers. This has led to the design of more advanced and economical power assisted drivetrain systems for wheelchairs. In this thesis, a novel controller has been designed. Instead of using a torque sensor for measuring and amplifying human force, the proposed controller uses two infrared sensors to trigger two motors. Using this information in addition to the information from a motion sensor that detects the road angle variation, appropriate torque command is generated. The drivetrain requires the embedded controller has a strong I/O control function, but also high speed signal processing ability for realizing real time control. Therefore, a DSP (Digital Signal Processor) which integrates flexbile multiple PWM signal generator to drive two motors, two Hall sensors for motor position and speed feedback is considered as one of the strongest controllers for power assisted drivetrain implementation. This thesis has two main contributions: a) it presents a novel power assisted motor control strategy, including six-step motor control, Environmental Adaptive control and Push-Go control method; and b) it develops an embedded controller not only on the testbench, also on the wheelchair to realize this control strategy. The designed controller is low cost and compact.
M.S. in Electrical Engineering, May 2012
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Title: The Morkrum system of printing telegraphy
Creator: Earle, Ralph H.
Date: 2009, 1917
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/morkrumsystemofp00earl
Thesis (B.S.)--Armour Institute of Technology, 1917 B.S. in Electrical Engineering, 1917

Title: A Practical Network Coding Scheme Over GF (2q) for Multi-User Cooperative Wireless Networks
Creator: Chang, Peiqiang
Date: 2011-04-21, 2011-05
Description: In this work, I present a non-binary Decode-and-Forward Network Coded (DFNC) protocol over GF(2q) for reliable communication in multi-user...
Show moreIn this work, I present a non-binary Decode-and-Forward Network Coded (DFNC) protocol over GF(2q) for reliable communication in multi-user cooperative wireless networks. There are two time phases in DFNC protocol: each user transmits its own data in the first time phase and serves as a relay in the second time phase to transmit the network coded information combining its own and others. In particular, a non-binary coding matrix construction method is proposed so as to reduce the transmission overhead and to provide independence for decoding. Moreover, we design a creative joint decoding algorithm: Credit-based Updating Algorithm (CUA), which works on symbol-level coupling network-decoding and channel-decoding together. By fully exploiting the spatial diversity and redundancy residing in network coding, CUA improves the solvability of decoding set at the destination, and therefore achieves better performance than traditional decoding algorithms, such as Gaussian Elimination. From the analysis and simulation results, we demonstrate that the proposed protocol achieves higher diversity order and outperforms other traditional transmission schemes in terms of Symbol Error Rate (SER).
M.S. in Computer Engineering, May 2011
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Title: DESIGN AND ANALYSIS OF AN UNCONVENTIONAL PERMANENT MAGNET LINEAR MACHINE FOR ENERGY HARVESTING
Creator: Zeng, Peng
Date: 2011-11, 2011-12
Description: The rise of global energy consumption and the growing trend to utilize clean energy stress the demand to harvest the untapped green energy...
Show moreThe rise of global energy consumption and the growing trend to utilize clean energy stress the demand to harvest the untapped green energy existing in every day life of human kind. Among the commonly over-looked energy resources, the kinetic motions including the vibration generated by linear motion and the vibration existent in ambient environment prove to own strong energy potentials. Though so far a number of such kinetic energy harvesters have already been studied, these existent energy harvesting devices can be improved on multiple aspects from power density, usage efficiency of expensive permanent magnetic material, to optimization of interface power electronics. This Ph.D. dissertation proposes an unconventional high power density linear electromagnetic kinetic energy harvester, and a high-performance two-stage interface power electronics to maintain maximum power abstraction from the energy source and charge the Li-ion battery load with constant current of low ripple at the same time. The proposed machine architecture is composed of a double-sided flat type silicon steel stator with winding slots, a permanent magnet mover, coil windings, a linear motion guide and an adjustable spring bearing. The unconventional design of the machine is that NdFeB magnet bars in the mover are placed with magnetic fields in horizontal direction instead of vertical direction and the same magnetic poles are facing each other. The derived magnetic equivalent circuit model proves the average air-gap flux density of the novel topology is as high as 0.73 T with 17.7% improvement over that of the conventional topology at the given geometric dimensions of the proof-of-concept machine. Subsequently, the improved output voltage and power are achieved. The dynamic model of the linear generator is also developed, and the analytical equations of output maximum xv power are derived for the case of driving vibration with amplitude that is equal, smaller and larger than the relative displacement between the mover and the stator of the machine respectively. Furthermore, the finite element analysis (FEA) model has been built and simulated to prove the derived analytical results and the improved power generation capability. Also, an optimization framework is explored to extend the dynamic system modeling method of the proposed single-Degree-of-Freedom (1-DOF) linear generator to the multi-Degree-of-Freedom (n-DOF) vibration based linear energy harvesting devices with multi proof masses and springs. Moreover, a boost-buck cascaded switch mode converter with current controller is designed to extract the maximum power from the harvester and charge the Li-ion battery with trickle current. Meanwhile, a maximum power point tracking (MPPT) algorithm is proposed and optimized for low frequency driving vibrations. Finally, a proof-of-concept unconventional PM linear generator is prototyped and tested to verify the simulation results of the FEA model. For the coil windings of 33, 66 and 165 turns, the output power of the machine is tested to have the output power of 65.6 mW, 189.1 mW, and 497.7 mW respectively with the maximum power density of 2.486 mW/cm3.
Ph.D. in Electrical Engineering, December 2011
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Title: PERFORMANCE ANALYSIS OF A NEW CLASS OF SPACE-TIME BLOCK CODES
Creator: Chahande, Pradnya
Date: 2013, 2013-07
Description: In today’s world the key challenges for wireless communication are the data rate and quality of service (QoS). Diversity schemes could lower...
Show moreIn today’s world the key challenges for wireless communication are the data rate and quality of service (QoS). Diversity schemes could lower the probability of outage thereby increasing the data rates and QoS. One method of diversity is deploying multiple antennas at the receiver and transmitter that create multiple-input multiple-output (MIMO) systems which not only increase the data rate, but also provide higher reliability, robustness and QoS as compared to single antenna systems. This work provides a comprehensive analysis of the performance of the space-time block codes in fading environment. We also provide a new space-time coding scheme based on circulant matrices, Circulant Space-Time Codes, which is linear and orthogonal with rate one for any number of transmitters. We calculate the pairwise error probability (PEP) under block fading environment. Then we use this PEP expression to calculate the union bounds on performance of the CSTCs. Simulation results shows that by increasing the number of receivers wherein number of transmitters increase the probability of symbol error rate would decrease. Since this code is orthogonal the decoding complexity is low as compared to other block codes.
M.S. in Electrical Engineering, July 2013
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Title: Power consumption of machine tools
Creator: Broyles, J. L., Kupshas, A. C., Rosenberg, L. H.
Date: 2009, 1917
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/powerconsumption00broy
Thesis (B.S.)--Armour Institute of Technology; Bibliography: leaves 84-85

Title: Rehabilitation of the municipal electric lighting system at Downers Grove, Ill.
Creator: Drew, H. A., Schuler, C. R.
Date: 2009, 1912
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/rehabilitationof00drew
Thesis (B.S.)--Armour Institute of Technology

Title: Relation between physical and magnetic hardness of certain carbon steels
Creator: Snowdon, C. R., St. Clair, O. A.
Date: 2009, 1905
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/relationbetweenp00snow
Thesis (B.S.)--Armour Institute of Technology

Title: HIGH GAIN HIGH EFFICIENCY RESONANT DC-DC CONVERTER
Creator: Shang, Fei
Date: 2016, 2016-12
Description: Low voltage power sources such as batteries, solar panels, and fuel cells have played an important role in applications such as automotive...
Show moreLow voltage power sources such as batteries, solar panels, and fuel cells have played an important role in applications such as automotive system, renewable energy power generation and so on. These applications of the low voltage power sources require a high gain DC-DC step-up converter. Research in this area shows great improvements for the converter topologies. As the power requirements keep increasing, the converter is going to sustain a very high input current. This high current can bring many design challenges in the existing topologies, such as high component current stress and power loss, complex and costly design for magnetic components, high input current ripple, etc. To address these challenges, a new topology of high gain DCDC step-up converter is needed. Evaluation of current high gain DC-DC converter topologies introduces the idea of the new topology which combines the advantages of different topologies and techniques. The new topology of high gain DC-DC converter suitable for low-voltage-high-current application is proposed in this dissertation. It consists of interleaved step-up topology, resonant circuit, and high frequency transformer. The topology has many merits such as high gain capability, high efficiency, low components stress and requirement of the transformer, simple topology with less number of active switching device, and easy to control. The dissertation carries out theoretical analysis of the proposed topology under different operating modes and the voltage gain has been deduced for each mode. The high voltage gain capability comes from 3 parts, which are interleaved step-up function, transformer turns-ratio and output voltage doubler circuit. Some variants of the topology make it more practical in many applications. In order to realize the design of the proposed converter, the design guidelines of major circuit components have been well studied in this dissertation. The switching power devices current stress and power loss are discussed in detailed to show the trend of their variation under different operating modes. The selection of transformer turns-ratio with the consideration of its impact to the component stress and power loss has been fully analyzed. The design method of the resonant tank is also well studied based on the resonant component value selection and its influence to the other components. Input inductor design is related to the current ripple requirement and this relationship is discussed thoroughly. These guidelines can be used to support the practical design of the proposed converter for different specifications. An effective output voltage regulation of the converter is essential for the proposed converter. To design a proper controller of the converter, the system transfer function is needed. The methods of system dynamic modeling have been fully studied in this dissertation. System dynamic state-space models are acquired by using generalized averaging method and the results validate the effectiveness of the method. Small signal model of the converter is achieved by linearization of the dynamic model around the operating points and system transfer functions are available at di↵erent operating points. The stability study indicates that the system is stable at all operating points, though there are several transfer functions at some operating points containing RHP zeros which can cause system unstable if the closed-loop controller is poorly designed. The parameter sensitivity study shows that the system transfer function is not greatly affected by the variation of the leakage inductance and load resistance. A design of PI controller is introduced in the dissertation and closed loop control of the converter is implemented to achieve the output voltage regulation. Simulations in PSIM and MATLAB Simulink have been carried out to validate the circuit operation and support the design analysis. A 2kW prototype has been built for experimental testing. The experimental results are in a good agreement with the theoretical analysis and efficiency of over 95% has been achieved for the nominal operating point.
Ph.D. in Electrical Engineering, December 2016
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Title: Oscillograph investigation of commutation with special reference to the effect of interpoles upon the commutating conditions.
Creator: Peebles, James Clinton
Date: 2009, 1908
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/oscillographinve00peeb
Thesis (B.S.)--Armour Institute of Technology, 1908 B.S. in Electrical Engineering, 1908

Title: An Oscillographic investigation of current and EMF- waves of telephone magneto generators
Creator: Morrison, Rudolph A, Lurvey, David, Reker, William
Date: 2009, 1907
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/oscillographicin00morr
Thesis (B.S.)--Armour Institute of Technology

Title: MARKET DOMINANT PLUG-IN HYBRID ELECTRIC VEHICLES OPTIMAL CONTROL FOR MINIMUM CHARGING COST AND V2G REGULATION SERVICE
Creator: Li, Zhihao
Date: 2012-07-23, 2012-07
Description: Plug-in hybrid electric vehicles (PHEVs) share the characteristics of hybrid electric vehicles (HEVs) and electric vehicles (EVs), employing...
Show morePlug-in hybrid electric vehicles (PHEVs) share the characteristics of hybrid electric vehicles (HEVs) and electric vehicles (EVs), employing electric motors and internal combustion engines (ICEs) for propulsion as well as large capacity batteries for energy storage. With ICEs and fuel tank on board, PHEVs do not have the range limitations posed by EVs; large capacity battery promises long distance all-electric range (AER) and fuel efficiency improvement. PHEVs will play a vital role in future as a sustainable transportation system, promising for environment, energy solution, and economy. It is estimated that by 2015, the total number of PHEVs in the world will be approximately 1.7 million with the U.S. marking leading the industry with about one million PHEVs. Growing penetration of PHEVs will place significant impacts on the grid, either as additional electric loads or potential assets which could provide various vehicleto- grid (V2G) services. There are four potential grid services that PHEVs can provide: base load generation, peak load shaving, spinning reserve, and regulation. PHEVs are not competitive in base load or peak load markets due to limited battery capacities. In addition, PHEVs are not real generating units and the energy stored in batteries is absorbed from grid. V2G support is taken into account as frequency regulation by participating in ancillary service markets. However, if implemented without proper control, large scale PHEVs will cause increases of peak load and destabilize the grid. This paper proposes an optimization strategy to maximize V2G profits as well as to minimize charging costs. The optimization strategy is based on a forecast of future electricity price for both residential electricity and regulation market. Due to the stochastic nature of electricity price, final prices cannot be deterministically calculated. Therefore, the addressed problem is solved by stochastic dynamic programming to find the economically optimal solution with price uncertainties. Constraints caused by vehicle utilization as well as technical limitations are taken into account. Additional costs arising from discharging batteries for ancillary service can be partially or completely compensated by V2G profits. In this Ph.D. research work, economical impacts of PHEV fleet are examined in Pennsylvania Jersey Maryland (PJM) regulation market. The major contributions of this paper are: Mathematically model the optimal control of PHEV with comprehensive transition function and cost function; A full study of battery life and cost that considers different ageing factors; A stochastic study of uncertainty and volatility in electricity price; Include battery degradation and price uncertainty in the comprehensive function for optimal control.
Ph.D. in Electrical Engineering, July 2012
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Title: BANDWIDTH ENHANCEMENT OF A COMPACT ANTENNA BY PARASITIC ELEMENTS
Creator: Celebi, Adem
Date: 2015, 2015-05
Description: Antenna structures are playing a major role in wireless systems, including communication systems, radars, satellite systems, information...
Show moreAntenna structures are playing a major role in wireless systems, including communication systems, radars, satellite systems, information networks and medical diagnostic systems. In these systems, external antennas are widely used, especially for devices with metallic enclosures. One of the common requirements for the ex- ternal antennas is the need for achieving small dimension while keeping the antenna performance optimized. In this respect, electrically small antennas (ESAs) are em- ployed. Realizing the design requirements of an ESA has been a challenge for antenna designers because some of the parameters such as large bandwidth and reasonably high input impedance are in conflict with the small antenna dimensions. A compact antenna with parasitic elements for bandwidth enhancement is proposed to address these issues for use with mobile devices. Loading the known antenna topologies with other structures could improve the design parameters such as gain, bandwidth, impedance, and beamwidth for antenna topologies which are impossible to achieve with the conventional antennas. In this respect, a parasitic element with a smaller scale is placed within the structure to obtain a second resonance close to the main antennas resonance for an increased bandwidth without increasing the overall dimen- sions of the antenna. This composite antenna is expected to have relatively high input impedances for each of the resonances, thus minimizing the need for an input matching network. A review of related prior work of antenna structures is presented to gain insight into the recent developments and methods in the field. The mini- mum quality factor (Q) and maximum gain of the ESA designs and their theoretical Antenna structures are playing a major role in wireless systems, including communication systems, radars, satellite systems, information networks and medical diagnostic systems. In these systems, external antennas are widely used, especially for devices with metallic enclosures. One of the common requirements for the ex- ternal antennas is the need for achieving small dimension while keeping the antenna performance optimized. In this respect, electrically small antennas (ESAs) are em- ployed. Realizing the design requirements of an ESA has been a challenge for antenna designers because some of the parameters such as large bandwidth and reasonably high input impedance are in conflict with the small antenna dimensions. A compact antenna with parasitic elements for bandwidth enhancement is proposed to address these issues for use with mobile devices. Loading the known antenna topologies with other structures could improve the design parameters such as gain, bandwidth, impedance, and beamwidth for antenna topologies which are impossible to achieve with the conventional antennas. In this respect, a parasitic element with a smaller scale is placed within the structure to obtain a second resonance close to the main antennas resonance for an increased bandwidth without increasing the overall dimen- sions of the antenna. This composite antenna is expected to have relatively high input impedances for each of the resonances, thus minimizing the need for an input matching network. A review of related prior work of antenna structures is presented to gain insight into the recent developments and methods in the field. The mini- mum quality factor (Q) and maximum gain of the ESA designs and their theoretical limitations are then discussed. The features of the antenna designs discussed in the review are used as foundation of the developed antenna structures. The properties and a fabrication method of the proposed antenna are then discussed. A commer- cially available software package based on finite element method is employed to aid in the antenna design. Several antenna prototypes are constructed to verify the design and the accuracy of the simulations. The prototypes are then tested using network analyzers and an RF anechoic chamber with the aim of characterizing the antenna performance in terms of antenna bandwidth and input impedance.
Ph.D. in Electrical and Computer Engineering, May 2015
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Title: SURVIVABLE OPERATION OF THREE PHASE AC DRIVES IN WIND GENERATOR SYSTEMS
Creator: Shi, Xiaodong
Date: 2012-04-06, 2012-05
Description: Recent years have seen significant popularity in the use of wind generators owing to the depletion of natural resources and growing concerns...
Show moreRecent years have seen significant popularity in the use of wind generators owing to the depletion of natural resources and growing concerns about our environment. However, this development has raised issues concerning reliability of the wind turbine components. Among these faults, failure of current sensors is one of most common faults that can bring the wind generator to a standstill and lead to reduction in power yield. In addition, unscheduled maintenance often results in longer downtime and causes reduction of wind plant availability especially for those wind turbines located offshore or in remote areas. This dissertation proposes a survivable drive method to continue to operate the wind turbine in spite of current sensor failure. One of the common control strategies for the optimal of three-phase AC generators is vector control. Therefore, vector control method is implemented in this dissertation for both induction machine and Brushless PMSM. In order to achieve survivability when current sensor fault happens, a simple and effective method which doesn’t rely on current feedbacks is required as a backup control strategy. For this purpose, a digital control strategy is proposed for an induction machine and a Brushless PMSM. In addition, a current sensor failure detection method is designed to trigger the transition and a smooth transition method (only for induction machine) is implemented to ensure the smoothness of the control transition without stopping the system. Simulation and experimental results have been presented to prove feasibility and demonstrate the effectiveness of the proposed strategy.
Ph.D. in Electrical Engineering, May 2012
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Title: ESTIMATION OF THERMAL STATE OF CHARGE FOR PCC BASED LITHIUM-ION BATTERY PACKS
Creator: Salameh, Mohamad
Date: 2016, 2016-07
Description: With continuing efforts to improve energy and power density of Li-ion batteries, heat generation and thermal safety remain critical barriers...
Show moreWith continuing efforts to improve energy and power density of Li-ion batteries, heat generation and thermal safety remain critical barriers to commercial success. Energy conversion in a battery is an exothermic process. Whenever the temperature of lithium-ion batteries increases, there can be direct consequences-reduced calendar and cycle life and higher risk of a battery re or explosion. Conventional approaches to prevent overheating use active thermal management systems, such as air conditioning or liquid cooling. However, these systems can be costly, bulky, and consume energy during operation. In addition they o er no overheat protection while the application or the vehicle is powered down. Phase change material composites (PCC) can be employed to rapidly absorb heat from the battery and distribute it, thereby enabling lightweight and compact packs with extended cycle-life and safety. This thesis proposes an online temperature estimation technique for a novel intelligent battery thermal management to actively monitor thermal mass of the phase change material. Such a system will not only enable avoidance of thermal issues, but will extend life of the battery pack by optimally selecting the operating point of the Energy Storage System. It can also be used to predict when active cooling should be employed just before the battery exits the phase change temperature plateau, to ensure latent heat absorption is spread across the entire drive cycle.
M.S. in Electrical Engineering, July 2016
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Title: On the Global Behavior of a Buck Converter with a Constant Power Load and a Non-Linear Feedback
Creator: Veigas, Santhosh Jeethan
Date: 2011-01-26, 2011-05
Description: In distributed power electronic systems, DC-DC converters feed power to other downstream converters. When the downstream converters are...
Show moreIn distributed power electronic systems, DC-DC converters feed power to other downstream converters. When the downstream converters are tightly regulated they tend to draw a constant amount of power from the source converter and exhibit dynamic negative resistance. This results in stability problems for the source converter. The negative-impedance instability is documented in literature and a novel nonlinear loop-cancellation feedback has been suggested as one of the solutions to overcome the destabilization effects of downstream converters representation by a constant power load. In this work we study the effect of this loop-cancellation feedback on the global behavior of the system, including the size of the stable region around the operating point. To perform this study we use a phase portrait technique that has been applied previously to study the global behavior of the distributed DC-DC power electronic systems. The large-signal averaged model of the converter is used to develop phase portrait. The basin of attraction of the stable operating point equilibrium is determined and the effect of variations int he grain of the nonlinear loop-cancellation feedback is examined. Comparisons of the size of the basin of attraction and the speed of recovery from perturbations from the equilibrium point are made. The case where the gain is zero refers to the nonlinear loop-cancellation being absent is included.
M.S. in Electrical Engineering, May 2011
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Title: DEFORMABLE MESH MODEL OF CARDIAC MOTION FROM MRI DATA
Creator: Parages, Felipe M.
Date: 2011-04-25, 2011-05
Description: Estimation of myocardial motion from medical images is an important problem in several fields such as computer-aided diagnosis of cardiac...
Show moreEstimation of myocardial motion from medical images is an important problem in several fields such as computer-aided diagnosis of cardiac lesions, development of cardiac simulators, and cardiac image processing in general. Tagged Magnetic Resonance Imaging (tagged MRI) is an image modality in which magnetic markers (taglines) track true deformation of heart tissue, thus being a valuable tool to analyze cardiac motion. Although several methods to analyze cardiac motion from tagged MRI have been proposed in the past, many of them rely somewhat on manual intervention to correct loss of tagline contrast towards the end of the cardiac cycle. Likewise, some of these methods are based on tagged MRI only, failing to include motion information from untagged (cine) gated cardiac MRI. We present in this thesis a model that overcomes these limitations by using a regularized non-rigid Deformable Mesh Model (DMM) to track pixel-intensity variations over combined datasets of gated tagged and cine MRI. DMM performs motion estimation directly over MRI pixel intensities, and proved to achieve motion analysis results comparable to other methods in which manual fine-tuning of tagline tracking is required. In addition, incorporating information from gated cine MRI into DMM proves to be helpful into capturing cardiac motion more efficiently. Finally, we show in this work the capacity of DMM to accurately estimate geometric and mechanical properties of the myocardium, such as strain and ejection fraction. We conclude that DMM method has a great potential for cardiac motion modeling, and may constitute a good alternative to other techniques in the future.
M.S. in Electrical Engineering, May 2011
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Title: EVALUATION OF COMPUTER ALGORITHMS FOR THE ANALYSIS AND RECONSTRUCTION OF CARDIAC IMAGES
Creator: Parages, Felipe M.
Date: 2017, 2017-05
Description: In the medical imaging field, image processing algorithms must be evaluated by measuring performance at some clinically-relevant task of...
Show moreIn the medical imaging field, image processing algorithms must be evaluated by measuring performance at some clinically-relevant task of interest (i.e. task-based quality assessment). This dissertation relies on the task-based paradigm to evaluate motion-estimation and image-reconstruction methods, respectively, for two cardiac-imaging modalities, namely: cardiac-gated tagged Magnetic Resonance Imaging (MRI), and Single Photon Emission Computerized Tomography for Myocardial Perfusion Imaging (SPECT-MPI). First, a task-based approach is followed to evaluate three motion-estimation methods for clinical cardiac-gated tagged MRI, namely: non-rigid registration using a Deformable Mesh Model (DMM), Strain from Unwrapped Harmonic Phase (SUPHARP), and Feature-Based (FB) algorithms. More specifically, the goal is to quantify and rank their performances at both detection and estimation tasks. For detection, methods are evaluated per their ability to discern between normal and abnormal motion patterns in known cardiomyopathies (e.g. hypertension and mitral regurgitation). For estimation tasks, methods are evaluated per their accuracy at estimating several rotation/twist and strain features of clinical interest; since true values for these features are generally unknown, a statistical Regression Without Truth (RWT) model is adopted, which does not assume the existence of a “gold-standard” method to use as a ground-truth reference. Moreover, the RWT model provides with an objective figure-of-merit that allows ranking methods in absolute fashion. Second, a novel anthropomorphic Model Observer (MO) is proposed for optimization of SPECT-MPI reconstruction algorithms such as Filtered Back-projection (FBP) and Ordered-subsets Expectation Maximization (OSEM). MOs are computer models that aim to mimic the performance of human readers (typically radiologists) at some clinically relevant task of interest. The proposed MO is based on supervised machine-learning classification, for the diagnostic tasks of detection, localization and assessment of perfusion defects. The MO is trained using an ensemble of synthetic cases whose perfusion were scored (i.e. labeled) by human specialists. The trained MO is subsequently applied on images not read by humans (both synthetic and clinical), aiming to predict their diagnostic scores. Results show that the proposed MO accurately predicts human diagnostic performances. Furthermore, it generalizes well to new images not used during training, not only from different reconstruction algorithms, but also from synthetic to clinical cases.
Ph.D. in Electrical and Computer Engineering, May 2017
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Title: PRIORITY MECHANISM DESIGN FOR INCOMING TRAFFIC IN 4G LTE NETWORK
Creator: Desai, Niraj N.
Date: 2012-11-27, 2012-12
Description: Long Term Evolution (LTE) is currently being used for commercial networks and the same technology will also be used for Public Safety (PS)...
Show moreLong Term Evolution (LTE) is currently being used for commercial networks and the same technology will also be used for Public Safety (PS) applications. As a way to maximize network usage and also to allow PS users to share the commercial networks especially during emergency or disaster situations, PS users need to co-exist with commercial users in a shared network environment. To ensure proper assignment of resources in a network originated call scenario, priority mechanisms have been proposed in this report. Priority mechanism in terms of assignment of resources for the user plane, for scheduling of resources in the control plane, and for meeting Quality of Service (QoS) requirements have been discussed. To provide priority treatment, the use of a new parameter named Call Priority Number (CPN) generated by the Policy control and Charging Rules Function (PCRF) is proposed. This parameter signifies the priority of a call in terms of the caller priority, the callee priority and the priority of the application. For incoming calls, the functionality of providing priority mechanism for resource assignment using CPN is proposed to be in the Mobility Management Entity (MME). The functionality for scheduling resources in the control plane, for performing paging, for priority mechanism functionality that uses CPN and the implementation of using different paging cycles for the users based on their priority resides in the evolved NodeB (eNodeB). For managing the priority based on QoS, a mapping of the priority of applications served by LTE networks to the Differentiated Services has been proposed. The mapping can be implemented in the Packet data network Gate Way (PGW). The proposals are verified by simulation. The results show that the PS users are assigned the x required resources for the user plane, they get prioritized QoS treatment within the LTE network, and the PS users are given higher priority over the commercial users. As a result of the techniques proposed in this report, the time it takes to set up a call between PS users is reduced, the number of dropped calls for the PS user decrease, and the PS users have a faster access to network resources.
M.S. in Electrical Engineering, December 2012
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Title: Proposed hydro-electric development on the west branch of the Penobscot River in Maine
Creator: Walsh, Raymond L., Ehrman, Joseph S., Lill, Arthur C.
Date: 2009, 1913
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/proposedhydroele00wals
Thesis (B.S.)--Armour Institute of Technology; Bibliography: leaf 41

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