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(641 - 660 of 4,054)
Pages
- Title
- Method for Enhancing Diagnostic Images Using Vessel Reconstruction
- Creator
- Agam, Gad, Wu, Changhua
- Date
- 2012-03-20, 2010-08-24
- Description
-
A method for improving a thoracic diagnostic image for the detection of nodules. Non-lung regions are removed from the diagnostic image to...
Show moreA method for improving a thoracic diagnostic image for the detection of nodules. Non-lung regions are removed from the diagnostic image to provide a lung image. Vessels and vessel junctions of the lung(s) in the lung image are enhanced according to a first-order partial derivative of each of a plurality of voxels of the lung image. A vessel tree representation is constructed from the enhanced vessels and vessel junctions. The vessel tree representation can be subtracted from the lung image to enhance the visibility of nodules in the lung(s).
Sponsorship: Illinois Institute of Technology
United States Patent
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- Title
- Nonlinear Interactions as Precursors to Mode Jumps in Resonant Acoustics
- Creator
- Panickar, P., Srinivasan, K., Raman, G.
- Date
- 2005-09
- Publisher
- American Inst Physics
- Description
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This paper examines instability mode switching in various supersonic jet configurations that involve resonant acoustics. Resonant acoustics...
Show moreThis paper examines instability mode switching in various supersonic jet configurations that involve resonant acoustics. Resonant acoustics includes situations where flow instabilities are enhanced by feedback. The pressure spectra in such situations are rich in multiple modes, and mode switching can occur rather unpredictably. Our experiments reveal that mode switching and the number of nonlinear interactions are interconnected and this number increases just prior to a mode switch. We quantified nonlinear interactions by counting the number of such interactions occurring over a threshold level in the nonlinear cross-bicoherence spectrum and confirmed that nonlinear interactions are precursors to mode jumps. Further, this result was found to be independent of the threshold level. Moreover, if more than one instability mode coexisted, the decay of one and the persistence of the other caused a similar increase in nonlinearities. On the other hand, if there was no mode switch, the nonlinearities remained at comparable limits over the entire operating range. The latter part of the work focused on why difference interactions significantly outnumbered sum interactions in the spectra of shock-containing resonant flows. Using linear stability calculations it is shown that most of the difference interactions that occurred had a positive spatial growth rate and were, hence, unstable. In contrast, a majority of the sum interactions lay outside the amplified region which indicated that they tend to decay spatially. (c) 2005 American Institute of Physics.
http://dx.doi.org/10.1063/1.2008995
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- Title
- Mycoflora of Indoor Dust and Alternaria Alternata Growth on Building Materials
- Creator
- Simpson, Stacy
- Date
- 2011-10-27, 2011-12
- Description
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Alternaria alternata, a clinically significant mold species is associated with allergic disease and asthma. An indoor growth of A. alternata...
Show moreAlternaria alternata, a clinically significant mold species is associated with allergic disease and asthma. An indoor growth of A. alternata may initiate atopic symptoms, accumulate in dusts, and discolor and deteriorate indoor building materials. Environmental control should be the initial approach to maintain a healthy indoor environment and manage allergic diseases. The current thesis investigated indoor dusts from various environments for mold spores and Alt a 1. Laboratory studies were carried out to determine if or which commercially available mold-resistant treatments and building materials could efficiently decrease A. alternata growth and Alt a 1. The mycoflora of indoor dusts was microscopically examined and the clinically significant allergen from A. alternata, Alt a 1 was measured in sampled dusts using a monoclonal anti-recombinant Alt a 1 (rAlt a 1) enzyme linked immuno-sorbent assay (ELISA). To investigate building material susceptibility untreated, mildew-resistant painted, and commercially available biocide treated building materials were inoculated with A. alternata spores, incubated in a humidity controlled chamber, and compared for mold growth and the presence of Alt a 1. A photo-monitoring technique was used to survey and determine mold growth surface area coverage. Alt a 1 immuno-reactivity of superficial mold growths was analyzed with the ELISA. The microscopic speciation of mold spores indicated that a diverse mycoflora can be found in indoor dusts. Although A. alternata was found in low concentrations in a few samples, Alt a 1was below the limit of detection. Nevertheless, mold spores can significantly contribute to the complexity of indoor dusts. A. alternata grew on all tested building materials but both painted and treated building materials inhibited mold growth in comparison to untreated samples. Not all material surfaces contained detectable levels of Alt a 1. Comparisons between untreated and painted building material groups indicated that a significant difference between the Alt a 1 accumulation content could not be established. To establish a standard sampling protocol and reliable prevention methods for mold contamination and exposure more knowledge about indoor molds must be gained.
M.S. in Environmental Engineering, December 2011
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- Title
- Introspective Landscape: Efficient Residential Housing: Final Board1_001
- Creator
- Allen, Nate
- Date
- 2012-05, 2012-05
- Description
-
This project is a contemporary revisit of the ideas behind Frank Lloyd Wright's Usonian houses. The building consists of three separate...
Show moreThis project is a contemporary revisit of the ideas behind Frank Lloyd Wright's Usonian houses. The building consists of three separate dwelling units on the same lot, a variation from the typical Chicago three-flat in that, rather than the three units being stacked one on top of the other, they are ordered linearly one after the other. The primary advantage of this arrangement is that each unit is allowed access to the ground floor, and to one of the three designated courtyard areas.
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- Title
- Magnetic Modulator System
- Creator
- Anderson, Marvin E.
- Date
- 1962-07-17
- Description
-
Sponsorship: Armour Research Foundation of Illinois Institute of Technology
United States Patent
- Title
- Mixer-ejector Wall Pressure and Temperature Measurements Based on Photoluminescence
- Creator
- Taghavi, R.r., Raman, G., Bencic, Tj
- Date
- 2002-04
- Publisher
- American Inst Aeronaut Astronaut
- Description
-
Ejector side-wall pressure distribution is a key indicator of supersonic jet-mixer-ejector performance. When documenting pressure patterns on...
Show moreEjector side-wall pressure distribution is a key indicator of supersonic jet-mixer-ejector performance. When documenting pressure patterns on an ejector wall using pressure-sensitive paint (PSP), one has to consider temperature variations caused by the supersonic jet flow within the ejector because these can cause significant local errors in the PSP results. If the temperature sensitivity of PSP is not corrected for in complex internal supersonic flows, large localized errors could contaminate the results. In the present work, temperature-sensitive paint maps the temperature distribution on the ejector wall and corrects PSP results point-by-point for temperature sensitivity. The experiments were conducted on multijet supersonic mixer-ejector configurations with straight, convergent (6-deg), and divergent (6-deg) side walls. A comparison of corrected and uncorrected PSP readings shows that at M-j = 1.55, the error with respect to true data from static pressure ports can be reduced from 4.98 to 2.84% for the case of a simple ejector with parallel walls. For the complex 6-deg convergent ejector at M-j = 1.39, the error reduces by almost an order of magnitude (from 20.83 to 2.66%). Our results indicate that the use of this correction technique can significantly reduce PSP errors in complex internal supersonic flow situations.
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- Title
- MECHANICAL PROPERTIES AND SINTERING MECHANISMS OF POWDER METALLURGY TI6AL4V
- Creator
- Xu, Xiaoyan
- Date
- 2013, 2013-05
- Description
-
Titanium has been identified as one of the key materials with a high strength to weight ratio that can reduce the weight of components and...
Show moreTitanium has been identified as one of the key materials with a high strength to weight ratio that can reduce the weight of components and thereby reduce energy consumption. Single press and sinter as a powder metallurgy technique has the potential to provide cost effective components. Armstrong prealloyed Ti6Al4V, HDH prealloyed Ti6Al4V, HDH blended Ti6Al4V powder and their mixtures were pressed and sintered at different conditions. The chemistry, mechanical and microstructural properties have been investigated to establish optimum processing parameters. Sintered parts were sent to Oshkosh Truck to test and compared with aluminum and steel parts. The Titanium and Ti6Al4V parts were successfully applied and tested. All the specimens passed the load test without failures. The sintering mechanisms of Armstrong prealloyed Ti6Al4V powder were investigated. At relative sintered densities of 75% to 90% (around 900°C), surface diffusion cooperate with grain boundary diffusion, which leads to densification of the powder compact. Around 900°C, grain boundary diffusion controls the sintering process. At 1000°C, boundary diffusion made little contribution to the densification of the Ti6Al4V powder compact. Above 900°C and below 91% sintered density, boundary diffusion controls sintering. Lattice diffusion dominates the densification process at higher temperatures (1100°C~1300°C). The sintering of master alloy blended Ti6Al4V powder has been investigated in order to elucidate the mechanism of sintering. Both blended powder compacts and diffusion couples were investigated using backscattered imaging and energy xvi dispersive analysis to determine the phases present and diffusion path on sintering at 1000ºC and 1100ºC. It is shown that transient liquid phase sintering does not occur and the reason for the rapid sintering of this material is due to enhanced diffusion kinetics resulting from a combination of the concentration gradient and stress induced by a phase transformation in the ternary system.
PH.D in Materials Science and Engineering, May 2013
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- Title
- Neutron Discharge Tube
- Creator
- Reiffel, Leonard
- Date
- 1961-05-09
- Description
-
Sponsorship: Armour Research Foundation of Illinois Institute of Technology
United States Patent
- Title
- WEB-BASED CONTEMPORANEOUS DELAY ANALYSIS
- Creator
- Pektas, Murat
- Date
- 2011-11-22, 2011-12
- Description
-
The construction industry is fragmented due to the many stakeholders and the diverse phases involved in a construction project. On time,...
Show moreThe construction industry is fragmented due to the many stakeholders and the diverse phases involved in a construction project. On time, within budget, with required quality are essentials of a successful project. However, most construction projects are faced with delays, which obstruct success. To recover the damage caused by delays, both the delays and the parties responsible for them should be identified accurately. Daily window delay analysis outperforms other delay analysis methods, but it requires intensive day-by-day information. The information flow among the project stakeholders must be smooth and speedy at all stages of the production process not only to achieve the basic project objectives but also to let project stakeholders recognize the delays and the parties responsible for them in order to recover time and cost. The Internet is attractive for transferring information promptly and economically with no regional or temporal borders. To merge the power of the Internet and to ease time consuming delay analysis, a web-based application is proposed to analyze delays effectively and contemporaneously, to reduce time and cost, and to provide historical data. The application considers the day-by-day variation in critical path(s) during the project life cycle. The application gives accurate and repeatable results for apportioning project delays, accelerations and decelerations among involved parties. The manual effort required by traditional systems is minimized with the application’s simple, easy to use, yet effective and highly automated features. Moreover, the database structure of the application is designed to store and manage more than one project at a time to let its users calculate the overall performance of the company including all projects, and to calculate average durations for activities that can come up in future projects.
M.S. in Civil Engineering, December 2011
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- Title
- Empirical modeling of systems with output multiplicities by multivariate additive NARX models
- Creator
- Decicco, J., Cinar, A.
- Date
- 2000-06
- Publisher
- AMER CHEMICAL SOC
- Description
-
Multivariable additive NARX (nonlinear autoregressive with exogenous inputs) modeling of process systems is presented. The model structure is...
Show moreMultivariable additive NARX (nonlinear autoregressive with exogenous inputs) modeling of process systems is presented. The model structure is similar to that of a generalized additive model (GAM) and is estimated with a nonlinear canonical variate analysis (CVA) algorithm called CANALS. The system is modeled by partitioning the data into two groups of variables. The first is a collection of future outputs, and the second is a collection of past input and outputs and future inputs. This approach is similar to linear subspace state-space modeling. An illustrative example of modeling is presented on the basis of a simulated continuous chemical reactor that exhibits multiple steady states in the outputs for a fixed level of the input.
Endnote format citation for DOI:10.1021/ie9906464
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- Title
- A METHODOLOGY FOR MAJOR BUS ROUTE RESCHEDULING TO IMPROVE TRANSIT PERFORMANCE
- Creator
- Lu, Xi
- Date
- 2012-08-01, 2012-07
- Description
-
In a period of growing transit operating deficits, increasing attention and concern is being directed at both the decreasing levels of...
Show moreIn a period of growing transit operating deficits, increasing attention and concern is being directed at both the decreasing levels of productivity of transit systems in general and the broad differences in measured service performance compiled for various transit systems. The purpose of this study is an assist public transit managers by providing them with a mathematical technique to analyze the efficiency with which serviced is produced and the effectiveness with which it is consumed. By providing the analysis model which not requires an extensive amount of data, the operator can have tool for decision-making of profit and market growth. Thus, transit managers will be able to access the performance of the agency and areas where improvements can be realistically achieved. Using the urban operation of the Chicago Transit Authority, a transit performance model is developed to analysis efficiency and effectiveness of the city's bus system. As the system exists, there are 144 bus routes start and end, frequency of dispatching buses and ridership changes from Weekdays and Weekend, peak hour and off-peak hour. In many of these routes, vehicles are used inefficiently and ineffectively, only a few passengers carried in some routes in off-peak hour, yet in other routes through the Central Business District (CBD) area, there are always not enough buses in peak hour. Also, some routes cannot provide enough on-time arrival service and some special group like elderly and handicapped cannot receive enough service in certain area. The goal of case research is to determine to understand the transit performance of Chicago Transit Authority and to select the optimal improvement projects to maximize the performance in term of economy and social equity.
M.S. in Civil Engineering, July 2012
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- Title
- SUSTAINABLE NEW CITY MENTOUGOU, CHINA
- Creator
- Yin, Lu
- Date
- 2013-04-30, 2013-05
- Description
-
This thesis will demonstrate one of the first urban models for the future of China’s growth. The Urban Operating System and GPS make the smart...
Show moreThis thesis will demonstrate one of the first urban models for the future of China’s growth. The Urban Operating System and GPS make the smart city smarter by linking up networks of billions of distributed sensors, systems, and intelligence across urban environments via city-scale operating systems. Personal Rapid Transit system runs everywhere and it is accessed and ordered by smart phone. Green belt is the medium that links all the natural area and parks in the city which become the core element in the city because it plays the most important role. Two types of transportation system including the Meglev for 10 minute access to Beijing and the PRT system for all internal urban mobility. The population of the new city is 80000. 80% of the people live here and work here, 20% of the people live here but work in Beijing. 30% of the people will use PRT system everyday. All the city blocks are mixed-use blocks. There are several types of residential buildings including mid-rise, high-rise and Beijing traditional courtyard house. This sustainable new city provides quality of lift to all the people live in the city.
M.S. in Architecture, May 2013
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- Title
- Reaching Out and Beyond: Making Library Centered Connections
- Creator
- Han, Yi, Fu, Li, Fu, Jiaqi
- Date
- 2012-06-23, 2012-06-23
- Description
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This poster is presented at the 2012 American Library Association Annual Conference in the Anaheim Convention Center. The hub on campus,...
Show moreThis poster is presented at the 2012 American Library Association Annual Conference in the Anaheim Convention Center. The hub on campus, academic libraries play a significant role in promoting diversity and academic success. Library resources and services have a great impact on university’s recruitment, retention and graduation. This poster session discusses some innovative practices in outreach, effective support in student learning, diverse models in services, and successful approaches in connecting with the campus community.
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- Title
- DAMAGE DETECTION OF STRUCTURES USING INTERVAL FINITE ELEMENT METHOD
- Creator
- Venkitaraman, Shyamala
- Date
- 2012-04-16, 2012-05
- Description
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Health assessment and damage detection for existing structures is an essential procedure for their safe and reliable operation so that any...
Show moreHealth assessment and damage detection for existing structures is an essential procedure for their safe and reliable operation so that any catastrophic failure may be prevented in a timely manner. However, results obtained from a health assessment of a structure possess uncertainties in measurements, system properties and loads. Furthermore, the conventional deterministic structural analyses are incapable of considering these uncertainties, thereby resulting in error when estimating the state of health of a structure. Interval (unknown-but-bounded) representation is one method to quantify uncertainty in a physical system. Using an interval variable, the uncertain parameter is bounded between extreme values. In this work, a new method for damage assessment of structures is developed that utilizes the results from structural health assessment as uncertain input parameters in an interval finite element analysis scheme. This method, due to its capability of considering uncertainties, offers a more robust process for estimating the possible existence of damage and overall health of the structure. As an illustrative example, the method is applied for a failed sign support structure. First, the structure's response from previous health assessment procedure was used to construct uncertain interval responses. Then using these interval responses as input parameters, an interval finite element method was performed. The results of the analysis verify and correlate with the failure location of the actual structure. Moreover, the lifetime assessment of the structure obtained from this method is the lower bound of, and correlates with the actual failure time of the structure.
M.S. in Civil Engineering, May 2012
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- Title
- Laboratory Notebook 112
- Creator
- Zhang, Zhe, Varelis, Peter
- Date
- 2010-03-09T22:34:24Z
- Description
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This laboratory notebook relates to the "Heat Stability of Ricin in Phosphate Buffer System" project with Peter Varelis as the Principle...
Show moreThis laboratory notebook relates to the "Heat Stability of Ricin in Phosphate Buffer System" project with Peter Varelis as the Principle Investigator.
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- Title
- Alleviating Homelessness in Chicago: Alleviating Homelessness in Chicago - Poster
- Creator
- Degroff, Justin
- Date
- 2011, 2011-05
- Description
-
Alleviating homelessness in Chicago through the creation of a network of self-sufficient, revenue generating support nodes.
- Title
- PARADIGM SHIFT IN REMOTE EDUCATION FOR THE LABORATORY: A SOCIAL APPROACH TO DISTANCE LEARNING
- Creator
- Hanley, Richard
- Date
- 2011-12, 2011-12
- Description
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With modern telecommunication tools the ability for two individuals to work together remotely has greatly improved. Moreover, there have been...
Show moreWith modern telecommunication tools the ability for two individuals to work together remotely has greatly improved. Moreover, there have been great strides made to improve handling medium to large groups of people in real time in remote settings, viz. the teleconference and webinar. However, the status of remote tools for laboratory environments where there is significant hardware and the individuals are more likely to talk amongst themselves in irregular patterns is not nearly as well studied. This thesis examines the way most laboratories in electrical engineering are setup, and creates a model for how to create a remote environment for distance learning. It then discusses the current state of the art, and how such an implementation of the model can be made with such tools. Finally a usability study of the implementation is examined. The primary result of the usability study is that when moving to a remote environment the social paradigm that students and instructors use is likely to change, and simply working on creating a virtual mirror to the laboratory may not work in the future.
M.S. in Electrical Engineering, December 2011
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- Title
- High-rise mix-use: Final MC Board
- Creator
- Mei, Chuan
- Date
- 2012-05-02, 2012-05
- Title
- Development of High Bandwidth Powered Resonance Tube Actuators with Feedback Control
- Creator
- Raman, G., Khanafseh, S., Cain, A. B., Kerschen, E.
- Date
- 2004-01-22
- Publisher
- Academic Press Ltd Elsevier Science Ltd
- Description
-
A high bandwidth powered resonance tube (PRT) actuator potentially useful for noise and flow control applications was developed. High...
Show moreA high bandwidth powered resonance tube (PRT) actuator potentially useful for noise and flow control applications was developed. High bandwidth allows use of the same actuator at various locations on an aircraft and over a range of flight speeds. The actuator selected for bandwidth enhancement was the PRT actuator, which is an adaptation of the Hartmann whistle. The device is capable of producing high-frequency and high-amplitude pressure and velocity perturbations for active flow control applications. Our detailed experiments aimed at understanding the PRT phenomenon are complemented by an improved analytical model and direct numerical simulations. We provide a detailed characterization of the unsteady pressures in the nearfield of the actuator using phase averaged pressure measurements. The measurements revealed that propagating fluctuations at 9 kHz were biased towards the upstream direction (relative to the supply jet). A complementary computational study validated by our experiments was useful in simulating the details in the region between the supply jet and the resonance tube where it was difficult to gather experimental data. High bandwidth was obtained by varying the depth of the resonance tube that determines the frequency produced by the device. Our actuator could produce frequencies ranging from 1600 to 15,000 Hz at amplitudes as high as 160 dB near the source. The frequency variation with depth is predicted well by the quarter wavelength formula for deep tubes but the formula becomes increasingly inaccurate as the tube depth is decreased. An improved analytical model was developed, in which the compliance and mass of the fluid in the integration slot is incorporated into the prediction of resonance frequencies of the system. Finally a feedback controller that varied both the resonance tube depth and spacing to converge on a desired frequency was developed and demonstrated. We are optimistic that numerous potential applications exist for such high bandwidth high dynamic range actuators. (C) 2003 Published by Elsevier Science Ltd.
http://dx.doi.org/10.1016/S0022-460X(03)00212-8
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