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Title: Magazine for Magnetic Recording and Reproducing Devices
Creator: Camras, Marvin
Date: 1949-10-11
Description: Sponsorship: Armour Research Foundation of Illinois Institute of Technology
United States Patent

Title: The Rotten IPRO (Semester Unknown) IPRO 312
Creator: Cargill, Matthew, Coad, Matthew, Dominski, John, Gulling, Richard, Karpuzi, Isida, Morton, Stacy, Nielsen, Lisa, Oblenida, Cindy, Olichwier, David, Rossi, James, Ryan, Emily, Szpiech, Paulina
Date: 2009, 2009-05
Description: Our team, IPRO 312: The Rotten IPRO’s goal is to determine the best method on how to recycle organic waste generated by the university....
Show moreOur team, IPRO 312: The Rotten IPRO’s goal is to determine the best method on how to recycle organic waste generated by the university. Research and analysis will inform us on whether initiating a composting facility on campus is feasible or not. The opening of a composting facility can reduce the university's environmental impact. Furthermore, IIT can serve as a model to expand composting across the city of Chicago.
Deliverables
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Title: SUBSTATION PLANNING FOR RURAL DISTRIBUTION SYSTEMS IN AFRICAN COUNTRIES
Creator: Soyoye, Oluwadamilola
Date: 2016, 2016-12
Description: In sub-Saharan Africa, only 35% of the population is connected to grid electricity [2]. Grid-connected parts face serious transmission and...
Show moreIn sub-Saharan Africa, only 35% of the population is connected to grid electricity [2]. Grid-connected parts face serious transmission and distribution challenges. There is also the challenge of electricity demand being greater than electricity supply. These issues in all levels of the traditional power system – generation, transmission and distribution have led to gross inadequacy of electricity supply. This research focuses on the capital intensive Power Distribution Planning (PDP). Most problems in the distribution system affect the consumer directly. Distribution substation planning, a critical part of the PDP, particularly addresses the issue of overloaded distribution systems. It is not uncommon for substation transformers in some African communities to become damaged because of overloading. The choice of location, sizing, siting and number of substations is determined by considering load distribution, feeder lengths and sizes, and the interruption costs. The research illustrates a framework for substation planning, incorporating possible future load growths over a particular period to forestall unwanted failures in the distribution system. A direct algorithm is used, where the substation capacity is computed manually from the load levels at different points. This algorithm is later combined with the Mixed Integer Linear Programming (MILP) approach solved with the CPLEX solver in MATLAB.
M.S. in Electrical Engineering, December 2016
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Title: High Speed Jet Flows, 1995: Presented at the 1995 ASME/JSME Fluids Engineering and Laser Anemometry Conference and Exhibition, August 13-18, 1995, Hilton Head, South Carolina
Creator: Raman, Ganesh, Kaji, S., Freitas, Christopher J.
Date: 1995
Publisher: American Society of Mechanical Engineers

Title: Automatic Insulin Pumps Using Recursive Multivariable Models and Adaptive Control Algorithms
Creator: Cinar, Ali, Oruklu, Meriyan
Date: 2014-04-09, 2014-04-08
Description: A method and device for monitoring or treating patient glucose levels. The device includes a glucose sensor for measuring a glucose level of a...
Show moreA method and device for monitoring or treating patient glucose levels. The device includes a glucose sensor for measuring a glucose level of a patient, a physiological status monitoring system for measuring at least one physical or metabolic variable of the patient, and an automatic controller in communication with the glucose sensor and the physiological status monitoring system. The controller includes a prediction module for automatically predicting a future glucose level using data measured by the glucose sensor and the physiological sensor.
Sponsorship: Illinois Institute of Technology
United States Patent
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Title: Tests on enameled wire
Creator: Gault, Mark E.
Date: 2009, 1911
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/testsonenameledw00gaul
Thesis (B.S.)--Armour Institute of Technology; Bibliography: leaf 26

Title: MINIMIZING SALMONELLA CONTAMINATION IN SPROUTS BY CONTROLLING THE GERMINATION TEMPERATURE
Creator: Zhang, Hanshuai
Date: 2013, 2013-12
Description: Since 1990, contaminated sprouts have been linked to at least 46 outbreaks and over 2,500 cases of illness in the US [13]. Unlike other ready...
Show moreSince 1990, contaminated sprouts have been linked to at least 46 outbreaks and over 2,500 cases of illness in the US [13]. Unlike other ready-to-eat produce, sprouts pose a particular concern as the conditions that promote germination of their seeds also facilitate the growth of pathogens [6]. To address sprout’s propensity to microbial contamination, the U.S. Food and Drug Administration (FDA) has recommended that seeds destined for sprout production be disinfected with chemical sanitizers such as 20,000 ppm of calcium hypochlorite, Ca(OCl)2 [29]. However, this disinfectant often cannot completely eliminate pathogen that may be present in seeds [4, 23]; in which case, the surviving bacteria can re-grow to significant numbers during germination and cause severe illness upon consumption [45]. Therefore, maintaining control of the germination conditions to present the proliferation of pathogens is a crucial step in the overall approach to reduce microbial hazards in finished sprouts. This study examines the effects of temperature on the proliferation of Salmonella during germination, and how this temperature effect is influenced by factors such as pathogen load, seed-lot, and the presence or absence of chemical treatment with Ca(OCl)2 was also evaluated. Alfalfa seeds artificially inoculated with ~3 log CFU/g of Salmonella were used as the contaminated seeds. They were mixed at different levels (0.01, 0.1, 1.0, or 10.0% by weight) with 200g of non-contaminated seeds and then were allowed to germinate in glass jars for 3 or 5 days at 10, 20, or 30°C. The same experiment was repeated for the spiking seeds that were treated with 20,000 ppm Ca(ClO)2 for 15 min prior to sprouting. Sprout samples were taken from each jar daily and analyzed for the level of Salmonella ix by either plating on XLD plates or the three-tube most probable number method as described in the FDA BAM. The level of Salmonella increased during sprouting at all three temperatures and reached the highest level at 48h. Sprouting at 10°C yielded the least number of Salmonella when all other factors were controlled. At all spiking levels, or the percentage of seeds contaminated before sprouting, level of Salmonella increased during sprouting, and at 20°C and 30°C, the level of Salmonella reached to a similar level of 5 log CFU/g and 7 log CFU/g respectively. At 1.0% spiking level, the level of Salmonella increased by approximately 1.5, 4.0, and 6.0 log CFU/g in sprouts grown at 10, 20, and 30°C respectively. Difference in the level of microflora background between different seed lots did not appear to affect Salmonella proliferation during sprouting. Treatments with 20,000 ppm free chlorine in some cases lowered the levels of Salmonella to undetectable levels, while in other cases, it caused an approx. 3 log reduction in Salmonella count on seeds. The surviving ones could still proliferate during sprouting although with a delay and a much slower rate, and did not reach the maximal level at 48 h of sprouting. However, Ca(OCl)2 did not prevent the re-growth of Salmonella during germination. In conclusion, these results showed that sprouting temperatures do affect Salmonella proliferations. We recommend lowering the sprouting temperature in conjunction with chemical treatment of prior to sprouting seeds to reduce microbial hazards in sprouts.
M.S. in Food Safety and Technology, December 2013
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Title: Sustainable Theme Park and Museum: KFujishima_Final Book
Creator: Fujishima, Kenta
Date: 5/4/2011, 2011-05
Description: An indoor facility consisting of both theme park and museum components with the integration of green and sustainable elements.

Title: LARGE-SCALE SIMULATION OF ELECTRIC POWER SYSTEMS FOR WIND
Creator: Wei, Tian
Date: 2011-08, 2011-07
Description: The utilization of wind energy will pose great socioeconomic benefits with reductions in power plant emissions and the supply of zero cost...
Show moreThe utilization of wind energy will pose great socioeconomic benefits with reductions in power plant emissions and the supply of zero cost energy; however, largescale wind energy integration could introduce inevitable challenges to regional transmission systems and hourly system operations. This thesis addresses the congestion identification, simulation and analysis of large-scale electric power systems in different scenarios, large-scale wind energy integration and related transmission expansion issues. A methodology based on the security-constrained unit commitment (SCUC) is applied to analyze the transmission congestions in the Eastern Interconnection of the United States. The identified congestions are visualized along with the Geographical Information System (GIS) data and compared with the results in National Electric Transmission Congestion Study (NETCS) published by the Department of Energy of the United States in 2006. The study also provides the locational marginal price (LMP) information in the Eastern Interconnection, which is not available in the NETCS report. This thesis implements a comprehensive simulation and scenario analysis of the Illinois electric power system for the year 2011. Possible scenarios representing electrical load sensitivities to economic growth, fuel price variations, and the impact of carbon cost, are studied. This thesis presents the hourly simulation results for the large-scale wind energy integration in the Eastern Interconnection of the United States. An hourly unit commitment is applied for the simulation of the economics of wind energy integration in the year 2030. The energy portfolio for supplying the hourly load in 2030 is developed based on wind integration levels. The sensitivities of fuel price, wind energy quantity, xvii load forecast, carbon cost, and load management to the proposed 2030 wind integration are studied. This thesis identifies transmission congestions and expands the existing transmission system in the Eastern Interconnection of the United States for accommodating a large-scale integration of wind energy. Violated transmission flows which would cause the infeasibility of hourly SCUC are identified. An iterative transmission expansion analysis is implemented to identify the minimum required additions to the Eastern Interconnection for mitigating hourly transmission congestions.
Ph.D. in Electrical Engineering, July 2011
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Title: DIRECT DIFFEOMORPHIC REPARAMETERIZATION FOR CORRESPONDENCE OPTIMIZATION IN STATISTICAL SHAPE MODELING
Creator: Li, Kang
Date: 2015, 2015-05
Description: This dissertation proposes an efficient optimization approach for obtaining shape correspondence across a group of objects for statistical...
Show moreThis dissertation proposes an efficient optimization approach for obtaining shape correspondence across a group of objects for statistical shape modeling. With each shape represented in a B-spline based parametric form, the correspondence across the shape population is cast as an issue of seeking a reparametrization for each shape so that a quality measure of the resulting shape correspondence across the group is optimized. The quality measure is the description length of covariance matrix of the shape population, with landmarks sampled on each shape. The movement of landmarks on each B-spline shape is controlled by the reparameterization of the B-spline shape. The reparameterization itself is also represented with B-splines and B-spline coefficients are used as optimization parameters. We have developed formulations for ensuring the bijectivity of the reparameterization. A gradient-based optimization approach is developed, including techniques such as constraint aggregation and adjoint senstivity for efficient, direct di↵eomorphic reparameterization of landmarks to improve the group-wise shape correspondence. Numerical experiments on both synthetic and real 2D and 3D data sets demonstrate the efficiency and e↵ectiveness of the proposed approach.This dissertation proposes an efficient optimization approach for obtaining shape correspondence across a group of objects for statistical shape modeling. With each shape represented in a B-spline based parametric form, the correspondence across the shape population is cast as an issue of seeking a reparametrization for each shape so that a quality measure of the resulting shape correspondence across the group is optimized. The quality measure is the description length of covariance matrix of the shape population, with landmarks sampled on each shape. The movement of landmarks on each B-spline shape is controlled by the reparameterization of the B-spline shape. The reparameterization itself is also represented with B-splines and B-spline coefficients are used as optimization parameters. We have developed formulations for ensuring the bijectivity of the reparameterization. A gradient-based optimization approach is developed, including techniques such as constraint aggregation and adjoint senstivity for efficient, direct di↵eomorphic reparameterization of landmarks to improve the group-wise shape correspondence. Numerical experiments on both synthetic and real 2D and 3D data sets demonstrate the efficiency and e↵ectiveness of the proposed approach.
Ph.D. in Mechanical and Aerospace Engineering, May 2015
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Title: Estimation of Future Glucose Concentrations with Subject-Specific Recursive Linear Models
Creator: Eren-oruklu, Meriyan, Cinar, Ali, Quinn, Lauretta, Smith, Donald
Date: 2009-04
Publisher: MARY ANN LIEBERT INC
Description: Background: Estimation of future glucose concentrations is a crucial task for diabetes management. Predicted glucose values can be used for...
Show moreBackground: Estimation of future glucose concentrations is a crucial task for diabetes management. Predicted glucose values can be used for early hypoglycemic/hyperglycemic alarms or for adjustment of insulin injections or insulin infusion rates of manual or automated pumps. Continuous glucose monitoring (CGM) technologies provide glucose readings at a high frequency and consequently detailed insight into the subject's glucose variations. The objective of this research is to develop reliable subject-specific glucose prediction models using CGM data. Methods: Two separate patient databases collected under hospitalized (disturbance-free) and normal daily life conditions are used for validation of the proposed glucose prediction algorithm. Both databases consist of glucose concentration data collected at 5-min intervals using a CGM device. Using time-series analysis, low-order linear models are developed from patients' own CGM data. The time-series models are integrated with recursive identification and change detection methods, which enables dynamic adaptation of the model to inter-/intra-subject variability and glycemic disturbances. Prediction performance is evaluated in terms of glucose prediction error and Clarke Error Grid analysis (CG-EGA). Results: Prediction errors are significantly reduced with recursive identification of the models, and predictions are further improved with inclusion of a parameter change detection method. CG-EGA analysis results in accurate readings of 90% or more. Conclusions: Subject-specific glucose prediction strategy has been developed. Including a change detection method to the recursive algorithm improves the prediction accuracy. The proposed modeling algorithm with small number of parameters is a good candidate for installation in portable devices for early hypoglycemic/hyperglycemic alarms and for closing the glucose regulation loop with an insulin pump.
Endnote format citation
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Title: Ethanol Ultra-Light Aircraft (Fall 2001) IPRO 317: Ethanol_Ultralight_IPRO317_Fall2001_Final_Presentation
Creator: Bockenfeld, Dan, Guerra, Jorge, Kuczaj, Mariusz, Lim, Ryan, Mcdaniel, Loren, Muliere, Dave, Orebaugh, Jesse, Parsons, Abigail, Williams, Ben
Date: 2001, 2001-12
Description: Students will convert a Quicksilver MXII ultralight airplane to run on E85 fuel (85% ethanol, 15% gasoline). This is technically challenging...
Show moreStudents will convert a Quicksilver MXII ultralight airplane to run on E85 fuel (85% ethanol, 15% gasoline). This is technically challenging because the plane uses a 2-stroke Rotax 503 engine, where the oil must be mixed in with the fuel. After the conversion, the plane will be flight-tested. In addition to the technical aspects, the project involves maintaining relationships with sponsors, public relations, and a study of the impact of ethanol on the ultralight aircraft market
Sponsorship: NA
Project Plan for IPRO 317: Ethanol Ultralight Aircraft for the Fall 2001 semester
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Title: infoMOTO - Information Tools to Enhance the Performance and Experience of Motorcyclists, Summer 2011, IPRO 308: Presentation
Creator: Hussain, Faraz, Sarsfield, Corey, Wang, Haochen, Perkins, Jeff, Charles, Joe, Siva, Arun
Date: 2011-06-17, 2011-07
Description: infoMoto is a user-friendly and affordable aftermarket device which provides accessible feedback to the rider and mechanic as to the safety...
Show moreinfoMoto is a user-friendly and affordable aftermarket device which provides accessible feedback to the rider and mechanic as to the safety and performance of the motorcycle, which enhances the overall riding experience. Unlike existing standard equipment which provides minimal information, infoMoto notifies the user of impending malfunctions in addition to providing diagnostic information. This device may also help the designers of future models of motorcycles to head off any impeding problems, increasing the quality of their product.
IPRO 308: infoMOTO for Summer 2011
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Title: THE RELATIONSHIPS OF BIOLOGICAL, PSYCHOLOGICAL, AND SOCIAL FACTORS TO PERCEIVED SEIZURE SEVERITY IN INDIVIDUALS WITH TEMPORAL LOBE EPILEPSY
Creator: Fong, Wing Man
Date: 2012-12-17, 2012-12
Description: Epilepsy is a chronic neurological condition that can cause negative consequences in all areas of life for people with the condition. Research...
Show moreEpilepsy is a chronic neurological condition that can cause negative consequences in all areas of life for people with the condition. Research evidence has led to the goal of treatment to gradually shift from targeting only reducing the frequency of seizures to decreasing individual’s perception of seizure severity. While several studies have suggested that psychological and social factors, in addition to epilepsy-related biological factors, can also impact seizure severity perception, this area has received much less attention in relation to individuals’ perception of seizure severity. Therefore, this study examined individuals’ perception of seizure severity using a biopsychosocial framework which takes into account biological, psychological, and social factors to develop a comprehensive understanding about the perception of seizure severity. 57 individuals from a neurology clinic at a tertiary medical center with a primary diagnosis of localization-related temporal lobe epilepsy participated in this study. They were interviewed for demographic information and were assessed using Quality of Life in Epilepsy-89, Beck Depression Inventory, Stressful Life Events Scale, and Liverpool Seizure Severity Scale. A Multiple regression analysis indicated that the number of antiepileptic drugs, perceived memory function, the number of stressful life events, and social support were all significant predictors of perceived seizure severity. The current findings supported a biopsychosocial approach in understanding the perception of seizure severity among people with epilepsy. Clinical implications of these findings are discussed.
M.S. in Psychology, December 2012
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Title: Performance Addendum: Filing the Void
Creator: Edwards, David
Date: 2012-04-24, 2012-05
Description: This project was done as a response to the thriving public performance community at the northern side of Grant park in Chicago, IL. As a...
Show moreThis project was done as a response to the thriving public performance community at the northern side of Grant park in Chicago, IL. As a former resident of the South Loop a rift was readily perceived between the North and South ends of the park in both venues for entertainment as well as general amenities. This project looked to fill a void on the south end of the park to create both a more welcoming outdoor space for the public but also to create a performance venue that could help bring business and pedestrian traffic to the southern end of the loop.
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Title: Design & Build Chicago Scale Model for Dynamic Disaster Simulation (Semester Unknown) IPRO 317
Creator: Balkany, Graham, Claxton, Matt, Correa, Jessica, Flores, Emmanuel, Hernandez, Yvonne, Kim, Jichul, Lebron, Chance, Leong, Erick, O’brien, Daniel, Martinez, Oscar, Robledo, Ruben, Rus, Bogdan, Russeva, Diyanna, Seo, Andrew, Sun, Meng
Date: 2008, 2008-07
Description: This is the second phase of this project as a continuation of Spring 2008 IPRO 317 and will have a focus for Summer 2008 on the computer...
Show moreThis is the second phase of this project as a continuation of Spring 2008 IPRO 317 and will have a focus for Summer 2008 on the computer program, the user interface, as well as completion of the first geographic area of the scale model. The objective of this project is to design and construct a 3-D scale model for the first portion of downtown Chicago (downtown Chicago has been subdivided into 6 portions). The model will be used to simulate and test the effectiveness of fire defense strategies to address fire or other catastrophes related to public health and safety. This model will include streets, buildings and detailed information that help the Chicago Fire Department in planning interventions, considering various scenarios and case studies. The model is being built in phases, with the overall design incorporating a sophisticated, computer-driven illumination scheme built within the model base. The model thus will be able to display animated scenarios of virtually any depth and focus, by means of time-varying color and brightness. CAD Computer-generated images and laser-cutting methods are the main techniques used to design and build the model, but hand craftsmanship is also necessary. The completed model will be fully modular, designed to transport easily to various facilities. The usefulness of the model thus will extend to many needs of the Chicago Fire Department and City of Chicago, as an educational tool within the department and for community outreach. Possible additional uses for the model will be wind tunnel measurement of pressure distributions to inform building design and City infrastructure needs, as well as the study of urban microclimates and the impact on building energy demand. There is also the potential for this model and its design approach to inform the development of scale models to depict the venues associated with the proposed 2016 Olympics along the Chicago lakefront. This project will include: (1) Identification of the scale, materials, technologies, and strategies for construction; (2) Physical mapping and computer modeling of the downtown built environment; (3) Design of the physical model and computer/electronic components; and (4) Construction of a reduced-area mock-up for final review and approval by the City of Chicago.
Sponsorship: Chicago Fire Department
Deliverables
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Title: DEPTH MAP PROCESSING FOR MULTI-VIEW VIDEO PLUS DEPTH
Creator: Vijayanagar, Krisha Rao
Date: 2014, 2014-05
Description: The world of multimedia and visual entertainment has grown in leaps and bounds in the past decade with 3-D television being one of the biggest...
Show moreThe world of multimedia and visual entertainment has grown in leaps and bounds in the past decade with 3-D television being one of the biggest technologies. Amongst several formats proposed for representing 3-D content, multi- view video plus depth (MVD) format has gained a lot of interest in the past few years. MVD requires that each view of a particular scene be accompanied by a per-pixel depth. This introduces new problems for compression and transmission of MVD content because a depth map has di erent characteristics from a color image. Keeping the MVD format and depth map characteristics in mind, we highlight three majors problems that plague the MVD format, namely, 1. depth map re nement. 2. depth map compression. 3. novel view synthesis using the depth map at the decoder side. In order to re ne a depth map, we propose a multi-resolution anisotropic di usion algorithm that is optimized to run in real-time thus ensuring that the encoder does not su er from additional latency. Next, we propose two unique solutions for compressing them. We rst propose a solution using the Layered Depth Video (LDV) concept using a rate-distortion optimized quadtree decomposition of the LDV using a novel two-mode block truncation code with improved prediction. We also propose a compression solution using compressive sensing (CS) concepts by creating a hybrid rate-optimized CS codec. This codec achieves two goals:- rstly, block classi cation to ensure lower decoder complexity and secondly, rate-distortion optimization of the measurement rate for each block that is to be compressively sensed. We then look at the view synthesis component of the MVD tool-chain which x is a time-sensitive process. Keeping decoding latency in mind, we propose a lookup- table based approach to the 3-D warping process with a simpli ed hole- lling algorithm that is not only competitive quality-wise with other schemes but is several times faster too. It is hopeful that the presented techniques can be used successfully to create MVD architectures for applications that need low-complexity encoding solutions.
PH.D in Electrical Engineering, May 2014
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Title: Inspection System and Method
Creator: Hansen, Wilbur W.
Date: 1961-07-25
Description: Sponsorship: Armour Research Foundation of Illinois Institute of Technology
United States Patent

Title: Selector System for Magnetic Wire Reproducers
Creator: Danisch, Marion S.
Date: 1949-09-06
Description: Sponsorship: Armour Research Foundation of Illinois Institute of Technology
United States Patent

Title: COMPUTER MODELING OF BREAST LESIONS AND STUDIES OF ANALYZER-BASED X-RAY IMAGING
Creator: Garcia, Luis De Sisternes
Date: 2011-11, 2011-12
Description: Phase-contrast x-ray imaging is an emerging technique that promises to yield highly sensitive medical images of soft tissue, which is...
Show morePhase-contrast x-ray imaging is an emerging technique that promises to yield highly sensitive medical images of soft tissue, which is difficult to observe via conventional radiography given its low X-ray attenuation differences. One of these phase-contrast techniques, known as analyzer-based imaging, has demonstrated that highly detailed breast tissue images can be obtained using synchrotron radiation. However, synchrotron facilities are impractical for clinical use. This thesis introduces studies and exposure consideration towards the application of analyzer-based imaging in a clinical environment, particularly in the context of breast imaging. It also introduces a computational breast lesion model that generates randomized three-dimensional phantoms which follow realistically the characteristics observed in real lesions. Moving analyzer-based imaging to clinical application requires the consideration of photon noise, inherent from the use of a photon-limited conventional source. We summarize the statistical properties in the presence of photon noise of two popular analyzer-based imaging techniques, known as diffraction-enhanced imaging (DEI) and multiple-image radiography (MIR). The statistics for MIR have not been previously derived and are introduced in this thesis. Comparison of the resulting statistical predictions with results obtained by Monte Carlo simulation validated the analysis. An expression for the maximum-likelihood (ML) solution for analyzer-based imaging is presented as a way of minimizing the effects of photon noise in the reconstruction of the object’s absorption, refraction and ultra-small angle scattering properties, and more practical maximum-likelihood expectation-maximization (ML-EM) and maximum-a-posteriori expectation-maximization (MAP-EM) solutions are also introduced. The behavior of the ML-EM and MAP-EM solutions was compared to the results produced by the five best-known analyzer-based reconstruction methods using computer simulations. The ML-EM and MAP-EM reconstructions proved closer to the theoretical values as they do not rely on commonly known limitations and approximations introduced by the other techniques. We introduce the development and evaluation of a new computational breast lesion phantom model that can simulate either massess or microcalcifications. The proposed tool allows the generation of a large number of randomized three-dimensional breast lesion simulations following desired characteristics normally used to describe breast lesions in clinical practice. The initial motivation for the development of this new phantom model was to enable the proposed evaluations of analyzer-based imaging to be achieved. However, the model became a major focus of this thesis because it improves significantly upon those that can be found in previous literature. The proposed lesion model can be used for evaluation studies across different breast imaging techniques, as well as for training purposes, so it is our hope that it could become an important resource for the broader mammography research community. As part of the lesion modeling research, we also introduce methods to computationally modify experimental mammography and analyzer-based images of breast tissue so that they present the generated tumor simulations embedded within their parenchyma realistically. The realism of the simulated lesion images was evaluated by comparison of 83 real tumor cases observed in mammograms with 83 constructed hybrid images in which simulated tumors matching the characteristics observed in the real cases were embedded, with healthy tissue acting as background. As a quantitative comparison, extracted features describing tumor shape and density showed no statistically significant differences between real and simulated tumors. A known computational tumor classification technique based on their shape observed in mammography was implemented and showed no significant performance differences between real and simulated cases, as well as showing good correlation with previously published performance results in real tumors. To measure the realism for use in human observer studies, we conducted a reader study in which 5 experienced radiologists were asked to judge whether each of the 166 images was real or simulated by assigning a score on a 7-point scale. The results were analyzed in a multiple-reader multiple-case statistical framework. The conclusion of the study was that the readers’ accuracy in assessing whether the lesions were real or simulated was not significantly better than random chance. This thesis also incorporates a reader study to evaluate the degree to which photon-limited analyzer-based images may be effective for visualization of breast cancer features. Our motivation was to establish the x-ray intensity that would be required to make these methods feasible, the purpose being to serve as a guide in parameter selection for future design of imaging hardware. We conducted a series of observer studies that quantify the performance of analyzer-based refraction images at different noise levels for the task of identifying subtle details present in breast tumors which are relevant to clinical diagnosis. The cases shown to the readers consisted of hybrid images where simulated lesions of known characteristics were computationally embedded in real breast analyzer-based background images. The original phase-contrast data was obtained using synchrotron radiation and was later modified to simulate the noise and blurring effects produced from a photon-limited source with a 300μm aperture size, similar to those used in a laboratory environment. Results showed that the analyzer-based imaging techniques statistically outperformed conventional mammography for the given task with an average of just 128 recorded photons per pixel in background image regions
Ph.D. in Electrical Engineering, December 2011
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