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- Title
- DEVELOPMENT OF AN EMBEDDED CONTROLLER FOR TWO QUADRANT OPERATION OF BLDC MOTORS IN AUTOMOTIVE APPLICATIONS
- Creator
- Liu, Yizhe
- Date
- 2011-07-06, 2011-07
- Description
-
Due to growing concerns over the availability of non-renewable petroleum products and the increasing emphasis on protecting our environment...
Show moreDue to growing concerns over the availability of non-renewable petroleum products and the increasing emphasis on protecting our environment from green house gas emissions, plug-in hybrid electric vehicle and hybrid electric vehicles have been gaining increasing popularity over recent years. This has led to the design of advanced drive systems using different electric motors such as BLDC, PMSM, IM and SRM. An electric motor/generator requires controller that not only has a strong I/O control function, but also high speed signal processing ability for realizing real time control. Therefore, a DSP (Digital Signal Processors), which integrates flexible multiple PWM signal generator, high speed high precision ADC and encoder interface for motor speed and position feedback, is considered as one of the strongest controllers for electric motor control. Owing to a growing emphasis on identification, interference, and communication of security services of drive train in intelligent PHEVs and HEVs, a DSP can also be used to identify and isolate security issues in the integrity of the drive train in PHEVs and EVs. This thesis has two main contributions: a) it focuses on the development of an embedded controller using TMS320LF2812 DSP to realize two quadrant control of the BLDC; and b) it develops an automotive test bench to identify and investigate some potential security issues using the embedded controller’s eCAN communication function.
M.S. in Electrical Engineering, May 2011
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- Title
- FORCED PERIODIC OPERATION OF TUBULAR REACTORS
- Creator
- Ozgulsen, F., Cinar, A.
- Date
- 1994-10
- Publisher
- PERGAMON-ELSEVIER SCIENCE LTD
- Description
-
Forced periodic operation of tubular reactors can increase conversion and yield if proper operating conditions and forcing policies are...
Show moreForced periodic operation of tubular reactors can increase conversion and yield if proper operating conditions and forcing policies are selected. A numerical approach is proposed for computing the effects of periodic input forcing by a shooting algorithm. Such computational tools permit the assessment of the benefits of forced periodic operation of a specific reactor system and the identification of the ranges of operating conditions where forced periodic operation is beneficial. This information provides valuable insight for planning detailed experimental studies. Determining the influential input variables and bracketing the ranges of the operating conditions for improving reactor performance will reduce significantly the experiments needed for selecting the most favorable reactor operation policies. The application of the numerical algorithm is illustrated by assessing the benefits of forced periodic operation to a CO oxidation reactor model. The results reveal substantial improvement in performance with slow cycling in feed concentration.
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- Title
- STATISTICAL METHODS FOR LARGE-SCALE TRANSPORTATION NETWORK TRAFFIC VOLUME FORECASTING
- Creator
- Meng, Xiao
- Date
- 2012-11-27, 2012-12
- Description
-
Forecasting is the procedure of making declarations about future events whose actual outcomes have not yet been observed. A lot of decisions...
Show moreForecasting is the procedure of making declarations about future events whose actual outcomes have not yet been observed. A lot of decisions are made based on predictions of future unknown events. Knowing the essence of forecasting, it is not hard to interpret what traffic volume forecasting is. Traffic volume forecasting is the process of estimating the number of vehicles that will be on a planned highway in the future. It plays important roles in different aspects of transportation and related field, such as highway level of service analysis, measure of effectiveness, highway improvement and expansion, geometric design and air quality analysis, etc. A good forecast is needed for decision making in future land use and transportation planning. City and county planners can provide useful information about land use planning and projected developments. County engineers may provide information about future county projects that may cause detours and changes in traffic patterns along a trunk highway. Highway designers need forecasted traffic volumes to ensure proper geometric designs. Since short term forecasting has been a hot topic on research, many statistical methods have been used, such as the mean, historical moving average, exponential smoothing, and autoregressive integrated moving average. Among them, Box Jenkins method (Autoregressive Integrated Moving Average) has been found as the best model on forecasting of time series data with seasonality and trend.
M.S. in Civil Engineering, December 2012
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- Title
- DYNAMIC SIMULATION AND LOAD MODELING FOR VOLTAGE RECOVERY STUDIES WITH THREE-PHASE AND SINGLE-PHASE INDUCTION MOTORS
- Creator
- Zhang, Jingpei
- Date
- 2017, 2017-05
- Description
-
Transient stability topics have been popular in modern power systems and time domain simulation provides an efficient evaluation for...
Show moreTransient stability topics have been popular in modern power systems and time domain simulation provides an efficient evaluation for correlative studies. So far, we have been working on developing advanced time-domain simulator TS3ph, which implements simulation on electromechanical level but with three-phase completed network model to enable unbalanced modeling and simulation. In this paper, modeling and development work of TS3ph are being introduced. Positive-sequence equivalent and three-phase based models, including static var compensator, governor and three-phase induction motor models, are built and validated to evaluate their dynamic behaviors in transient state. Moreover, research work on single phase induction motor model development, including important motor behaviors such as motor stalling, is also introduced in this paper for voltage collapse and recovery study. This is indeed the first time to apply such model on electromechanical simulator as well.
M.S. in Electrical Engineering, May 2017
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- Title
- Zero CommunIITy: A Prototype for a Zero-Energy Residential Development (sequence unknown), IPRO 323 - Deliverables: IPRO 323 Final Report F09
- Creator
- Bohac, Adam, Brady, David, Bueno, Juan, Coughlin, Daniel, Depalma, Lowell, Gonzalez, Juan, Gross, Josh, Hernandez, Carlos, Iversen, Jennifer, Mckinley, Keanen, Moceri, Michael, Modi, Nishant, Wisniewski, Anthony, Zacharias, Bryan
- Date
- 2009-12
- Description
-
The teams purpose is to seek a union between living comfortably and living sustainably. To design for a future Chicago‐area community, which...
Show moreThe teams purpose is to seek a union between living comfortably and living sustainably. To design for a future Chicago‐area community, which first minimizes its energy consumption and then uses the most sustainable methods to fulfill the remaining needs of the inhabitants. Ideally we will design a model community which will challenge conventions within the fields of design, planning, engineering, and everyday living. This community will also serve as an example to Chicago‐area municipalities about the benefits of sustainable planning, design, and living.
Sponsorship: Consultant from A. Epstein & Sons; Jeremy Poling
Deliverables for IPRO 323:Zero CommunIITy: A Prototype for a Zero-Energy Residential Development for the fall 2009 semester
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- Title
- TEMPERATURE PROFILES THROUGH THE SHELL IN EGGS HEATED BY INFRARED ENERGY
- Creator
- Guo, Jingxin
- Date
- 2012-07-30, 2012-07
- Description
-
Infrared heating is an effective method for surface pasteurization of shell eggs. As the external temperature reaches the inactivation...
Show moreInfrared heating is an effective method for surface pasteurization of shell eggs. As the external temperature reaches the inactivation temperature, internal temperatures could become great enough to denature albumen. However, the internal temperature of albumen at the shell cannot be measured directly. The purpose of this study is to use experimental data to understand the response of the albumen temperature at the shell to infrared radiation impinging at its outer surface. Fresh eggs were obtained from a local producer and refrigerated until needed. They were prepared for each experiment by overnight equilibration with ambient conditions. Each egg was placed on a metal stage over which an infrared lamp was positioned. The stage allowed a K-type thermocouple to be inserted through a small hole in the shell opposite of the shell area facing the lamp. The thermocouple was pushed into the egg such that the tip was against the inner surface of the shell just underneath the exposed area. The external temperature of this area was measured by an infrared pyrometer. Variables for these experiments were temperature of the IR lamp (277°C, 329°C, 391°C and 452°C), distance between shell egg and IR lamp (3.13 cm – 15.83 cm), and treatment time. All experiments share the same initial lag around 30s, suggested that the initial lag did not vary with changing of lamp-egg distances and lamp temperatures. After the initial lag, internal and external temperatures were found to increase at the same rate regardless of experimental parameters, indicating and equilibrium between the infrared energy impinging on the surface and its dissipation in the interior of the egg. The difference of temperature distributes between 10°C to 20°C. However, lowering lamp temperatures or increasing distances did not change this difference significantly. Moreover, the temperature gap sustains the same temperature after initial lag. The results showed that the internal temperature could be inferred via measuring external temperature. This is valuable in processing to maximize external surface temperature while protecting heat sensitive albumen. Future work will involve modeling the heating phenomenon to determine if knowing only the lamp temperature and distance is sufficient for predicting internal temperature.
M.S. in Food Processing Engineering, July 2012
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- Title
- Measurement of anisotropic radial flow rapidity, Proceedings of the XLIII International Symposium on Multiparticle Dynamics
- Creator
- Wu, Yuafang, Li, Lin, Li, Na
- Date
- 2013-09-15, 2013-09-15
- Publisher
- IIT Press
- Description
-
Using the sample of Au + Au collisions at 200 GeV generated by the AMPT with string melting model, the anisotropic amplitudes of azimuthal...
Show moreUsing the sample of Au + Au collisions at 200 GeV generated by the AMPT with string melting model, the anisotropic amplitudes of azimuthal distributions of total transverse momentum, mean radial (transverse) momentum, and multiplicity are first presented and compared. It shows that the azimuthal distribution of mean radial momentum well characterizes the radial expansion. So a measurement of the azimuthal distribution of mean transverse (radial) rapidity of final state particles is suggested. We further show that the isotropic part of the suggested distribution is the combination of isotropic radial expansion and thermal motion. The anisotropic amplitude characterizes the anisotropic radial flow, and coincides with the parameter of anisotropic radial flow rapidity extracted from a generalized blast-wave parametrization.
Sponsorship: IIT College of Science, High Energy Physics Division of Argonne National Laboratory
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- Title
- Design of a Large Scale Structure (sequence 315), IPRO 315 - Deliverables: IPRO 315 Poster F09
- Creator
- Aguilar-wedge, Carmen, Animashaun, Oladipo, Baur, Alex, Cullen, Michael, Hadi, Shuaib, Hedge, Namrata, Kuo, Steve, Lee, Christopher, Lee, Yongdoo, Rybaltowski, Karol, Scully, Dawveed, Shen, Jie-hua, Yousef, Shadi
- Date
- 2009-12
- Description
-
Located in Oakbrook, IL the architects and engineers of IPRO 315 will design a 22 story hotel. Together architects and engineers will modify...
Show moreLocated in Oakbrook, IL the architects and engineers of IPRO 315 will design a 22 story hotel. Together architects and engineers will modify and re analyze a structure created by pervious designers, and select any new materials for construction. In creating the hotel students will be responsible for the structural analysis of columns, beams, foundation, steel, and concrete design required to insure all serviceability requirements. The students will be required to follow the 2006 International Building Code, and secure the safety of all possible occupants. Management, leadership, ethics, and teamwork will be an integral part of building a large scale structure as students learn to work together on a “real life” project.
Deliverables for IPRO 315: Design of a Large Scale Structure for the fall 2009 semester
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- Title
- Learning Company, Literacy Center, Johannesburg, South Africa
- Creator
- Gray, Aisling
- Date
- 2010-07-29
- Title
- BICYCLE CRASH ANALYSIS IN CHICAGO
- Creator
- Van Nortwick, Taylor Wade
- Date
- 2013, 2013-07
- Description
-
The United States is making big plans for improvements in bicycle infrastructure. To best understand if the improvements will be successful in...
Show moreThe United States is making big plans for improvements in bicycle infrastructure. To best understand if the improvements will be successful in creating a safe network, a study was done to determine contributing factors in bicycle crashes. Bicycle and motor vehicle crash data from around Chicago between 2005 and 2011 was analyzed for significant factors in infrastructure, cyclist and motorist attributes. Temperature was used as a predictor of bicycle traffic due to the seasonality of bicycling in Chicago. It was found that more bicycles and vehicles result in higher crash rates. It was also found that on -street parallel parking, signalized, skewed and multiple legged intersections lead to higher crash rates.
M.S. in Civil Engineering, July 2013
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- Title
- Developing Web Applications for the Northern Illinois Hockey League (sequence unknown), IPRO 308 - Deliverables: IPRO 308 Final Report F09
- Creator
- Lucchesi, Kristin, Barksdale, Dustin, Hays, Julian, Bartus, Kryzystof, Perkins, William, Savage, Christopher, Scheer, Colin, Semenov, Vladimir, Vidutis, Mantas
- Date
- 2009-12
- Description
-
The NIHL is the largest hockey league in Illinois. It is also the largest youth all star hockey league in the US, serving over 300 youth teams...
Show moreThe NIHL is the largest hockey league in Illinois. It is also the largest youth all star hockey league in the US, serving over 300 youth teams and over 4,000 players. The team's purpose is to make the NIHL a web-based scheduling and scoring applications that can support their annual operations.
Sponsorship: Northern Illinois Hockey League(NIHL)
Deliverables for IPRO 308: Developing Web Applications for the Northern Illinois Hockey League for the fall 2009 semester
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- Title
- A Video Annotation and Indexing System (sequence unknown), IPRO 327 - Deliverables: IPRO 327 Midterm Presentation F09
- Creator
- Dhagam, Karthik, Donchev, Alexander, Homawoo, Sergio, Litas, Alexander, Orlichenko, Anton, Osswald, Christian, Petsod, Jason, Rawlings, Ori, Shaffer, Joshua, Smith, Antoinette, Yates, Andrew, Yu, Hee Jeoung
- Date
- 2009-12
- Description
-
Much information available on the Web is in video format. The problem with this medium is users cannot comment on particular scenes within the...
Show moreMuch information available on the Web is in video format. The problem with this medium is users cannot comment on particular scenes within the videos and there is no method of searching for specific content within the videos. The team proposes to develop a system that will allow users to make fine-grained comments on scenes within the video and then to use these comments to aid in search within videos.
Deliverables for IPRO 327: A video annotation and indexing system for the fall 2009 semester
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- Title
- MULTI-DIMENSIONAL BATCH SCHEDULING FRAMEWORK FOR HIGH-END SUPERCOMPUTERS
- Creator
- Zhou, Zhou
- Date
- 2016, 2016-05
- Description
-
In the field of high performance computing (HPC), batch scheduling plays a critical role. They determine when and how to process the various...
Show moreIn the field of high performance computing (HPC), batch scheduling plays a critical role. They determine when and how to process the various jobs waiting for service. Conventional batch schedulers allocate user jobs solely based on their CPU footprints. However, for a given user job, it requires many different resources during its execution, such as power, network, I/O bandwidth, etc. Today’s job schedulers rarely take into account these resource requirements which sometimes turn out to be the Achilles’ heel of system-wide performance. In this research, we propose a multi-dimensional batch scheduling framework for high-end supercomputers. Our research aims to treat these common but often ignored resources (e.g., power, network, bandwidth) as schedulable resource and further transform each scheduling into a multi-objective optimization process. Our main contributions consist of a set of scheduling models and policies, aiming at addressing the issues in batch scheduling for large-scale production supercomputers. We evaluate our design by means of trace-based simulations using real workload and performance traces from production systems. Experimental results show our methods can effectively improve batch scheduling regarding user satisfaction, system performance and operating cost.
Ph.D. in Computer Science, May 2016
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- Title
- Developing a Collaborative On-line Student Research Forum (sequence unknown), IPRO 321 - Deliverables: IPRO 321 IPRO Day Presentation F09
- Creator
- Abhay, Anandha, Cornelius, Zachary, Corsus, Tom, De Courten-myers, Maximilian, Eberlin, Adam, Kapaldo, James, Nicholson, Bethany, Sizyuk, Yuriy, Sundberg, Stephen
- Date
- 2009-12
- Description
-
ResearchWeb is meant to broaden IIT undergraduate participation beyond the existing mechanisms such as fellowships, research and reading...
Show moreResearchWeb is meant to broaden IIT undergraduate participation beyond the existing mechanisms such as fellowships, research and reading courses, and departmental projects. There is also the possibility of broadening this program to other scholarly individuals outside of the IIT undergraduate community. These individuals include IIT graduate students, students from other universities, and promising high school students. ResearchWeb is also meant to improve the transition, and perhaps promote if need be, the transition from undergraduate education to graduate education. This would be fulfilled through practical research experience.
Deliverables for IPRO 321:Developing a Collaborative On-line Student Research Forum for Fall 2009
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- Title
- Impacts of Sulfur Capture Technology in Coal Power Plants (sequence unknown), IPRO 302 - Deliverables: IPRO 302 Midterm Presentation F09
- Creator
- Contreras, Abraham, Dickman, Justin, Enadeghe, Gregory, Garcia Rodriguez, Hector, Haddad, Michael, Kyle, Ryan, Mongillo, Michael, Murphy, Ryan, Shonubi, Oluwaseun, Swillum, Bryce, Wolber, Brian, Worthon, Terrika
- Date
- 2009-12
- Description
-
The IPRO team was investigating the net impact of sulfur capture technologies used in current and next generation power plants in the United...
Show moreThe IPRO team was investigating the net impact of sulfur capture technologies used in current and next generation power plants in the United States. It planned to use this knowledge to determine which sulfur capture technologies produce the greatest benefit for industry and society and to find the marketability of the sulfur byproducts created in these power plants.
Sponsorship: Sargent & Lundy, LLC
These are the deliverables for IPRO 302: Impacts of Sulfur Capture Technology in Coal Power Plants from the Fall 2009 semester.
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- Title
- Diffractive cross sections implemented in PYTHIA8-MBR VS LHC results, Proceedings of the XLIII International Symposium on Multiparticle Dynamics
- Creator
- Goulianos, Konstantin
- Date
- 2013-09-15, 2013-09-15
- Publisher
- IIT Press
- Description
-
Diffractive cross sections implemented in the pythia8-mbr Monte Carlo simulation are reviewed and compared to results obtained at the Large...
Show moreDiffractive cross sections implemented in the pythia8-mbr Monte Carlo simulation are reviewed and compared to results obtained at the Large Hadron Collider.
Sponsorship: IIT College of Science, High Energy Physics Division of Argonne National Laboratory
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- Title
- OPTIMAL SIGNAL TIMING DESIGN FOR URBAN STREET NETWORKS UNDER USER EQUILIBRIUM BASED TRAFFIC CONDITIONS
- Creator
- Liu, Yi
- Date
- 2015, 2015-05
- Description
-
In the ever-growing travel demand, traffic congestion on freeways and expressways recurs more frequently at a higher number of locations and...
Show moreIn the ever-growing travel demand, traffic congestion on freeways and expressways recurs more frequently at a higher number of locations and for longer durations with added severity. This becomes especially true in large metropolitan areas. Particular to the urban areas, excessive crowdedness caused by inefficient traffic control also results in urban street networks operating in near or over-saturated conditions, leading to unpleasant travel experience due to long delays at intersections. As a consequence, the recurrent traffic congestion on roadway segments and vehicle delays at intersections inevitably compromise energy efficiency, traffic mobility improvement, safety enhancement, and environmental impacts mitigation. All too often, neither restraining travel demand nor expanding system capacity is desirable and practical. Conversely, effectively utilizing the capacity of the existing transportation system has been increasingly thought of as the solution to congestion relief. With respect to the urban street networks, developing effective means for urban intersection signal optimization becomes essential to reduce intersection delays. Conventional signal timing optimization methods use historical traffic data and assume that traffic flows will remains unchanged after the implementation of new signal timing plans. Traffic flows are assumed to be constant, but in fact, when signal timing plans change, travel times for some travel routes will alter, which requires drivers in the network to adjust their choice of travel routes to arrive at the destinations, and result in redistribution of traffic in the network. Therefore, the effects of interactions between signal timing plans and traffic flows need to be explicitly taken into consideration. This study introduces a new methodology that jointly considers signal timing optimization and traffic assignment in an overall analytical framework that contains model formulations under assumptions consistent with real world situations. Such a framework is well suited for applications in real world cases. Specifically, the overall optimization framework is formulated as a bilevel optimization problem. In the proposed basic model, at the upper level, a traffic signal timing optimization problem for urban network is introduced to minimize system total travel time by optimizing signal green splits. At the lower level, a static user equilibrium problem is formulated for networkwide traffic assignment. In the vehicle delay estimation, the time-dependent stochastic delay model in the 2010 Highway Capacity Manual (HCM 2010) is employed and formulated as Variational Inequality constraints, what allow the state-of-the-art MPEC solver, GAMS/NLPEC, to solve the problem for a local optimal effectively and efficiently. The bi-level optimization model is first tested using a small network (the test network) and a computational experiment using a subarea network in the Chicago central district is conducted to assess the practicality of the model formulation in real world applications. In order to import more reality to the basic model and also consider the potential system benefit that comes from different signal phasing design, an enhanced model is developed based on the basic model by employing integer and binary variables. Formulating the problem with binary variables allows for the selection of proper phasing design. Heuristic solution methods are proposed and tested using the test network.
Ph.D. in Civil Engineering, May 2015
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- Title
- DEVELOPMENT AND APPLICATION OF THE KIRIE WASTEWATER TREATMENT PLANT MODEL
- Creator
- Mendez, Thomas E.
- Date
- 2012-07-15, 2012-07
- Description
-
The Metropolitan Water Reclamation District of Greater Chicago (MWRDGC) is tasked with protecting the public’s water supply and improving the...
Show moreThe Metropolitan Water Reclamation District of Greater Chicago (MWRDGC) is tasked with protecting the public’s water supply and improving the quality of water in their service area’s watercourses. Principal in this mission are the seven wastewater treatment plants that are operated by MWRDGC. The greater Chicago area possesses a combined sewer system (CSS) that combines sanitary sewage and stormwater runoff. Because of this CSS, water reclamation plants are burdened with not only processing sewage and sanitary waste, but also stormwater runoff. As a result there can be a large variation in water quality and quantity. MWRDGC’s newest water reclamation plant is the James C. Kirie Water Reclamation Plant, which was completed in 1980. This plant operates as a nitrification plant with no separate distinct denitrification process. It is important to note that no clearly defined unit processes such as nitrification towers are utilized at the Kirie Water Reclamation Plant. Nitrification occurs primarily in the aeration basins and is currently sufficient to meet water quality standards. However, because of the current regulatory climate, stricter standards on effluent discharge are likely in the near future especially with respect to nutrients. Stricter standards on total nitrogen in effluent instead of the current ammonia limits are one such expected water quality change. As a result of this expectation, modeling modifications and processes at a treatment plant can be a key tool in adjusting to evolving standards. Because water reclamation plants vary greatly depending on their technology, influent and processes, computer modeling provides a convenient way to assess how the plant will react to dynamic changes in influent quality and still be able to meet static effluent standards. Although computer modeling has been applied to water reclamation plants for some time now, there are no clearly defined or accepted protocols for this modeling. Combined with the variation exhibited by various types of water reclamation plants, often modeling protocols must be custom created for individual plants or types of plants. What follows is a study and simulation of the Kirie Water Reclamation Plant. Simulation was used to examine wet weather events at the Kirie Water Reclamation Plant. Wet weather phenomena were explored in step-wise manner to determine the relative effects of different perturbations in influent water quality and quantity. The results show the various effects in effluent quality depending upon the variable or combination of variables deviated. Deviations in temperature and flow dominate all other variations simulated and result in the largest effect on effluent water quality. Deviations of 50% to both temperature and flow simultaneously yielded an increase in effluent BOD and NH3 at twice and six times the steady state values, respectively.
M.S. in Environmental Engineering, July 2012
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- Title
- Power Measurement for Road Bicycles: Towards a Universal Solution (sequence unknown), IPRO 324 - Deliverables: IPRO 324 Poster F09
- Creator
- Adrianzen, Luis, Allen, Ross, Antonio, Chris, Callan, Mark, Claxton, Sara, Diesse, Patrick, Gaylord, Matthew, Herbert, Greg, Shaffer, Dan, Wegrzyn, Celeste
- Date
- 2009-12
- Description
-
The goal of the IPRO is to try to find an inexpensive, but accurate way of measuring the power output of a rider on a bicycle. Problems with...
Show moreThe goal of the IPRO is to try to find an inexpensive, but accurate way of measuring the power output of a rider on a bicycle. Problems with systems currently available are: some products are not compatible with all bike systems causing the need to purchase new parts, the cost of the available products is expensive, and some of the available measuring systems are not very accurate.
Deliverables for IPRO 324: Power Measurement for Road Bicycles: Towards a Universal Solution for the fall 2009 semester
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- Title
- DISRUPTION OF EPILEPTIC SEIZURES USING TARGETED MULTI-SITE ELECTRICAL STIMULATION
- Creator
- Sobayo, Tiwalade
- Date
- 2015, 2015-12
- Description
-
Neuronal populations in the brain achieve levels of synchronous electrophysiological activity during both normal brain function and...
Show moreNeuronal populations in the brain achieve levels of synchronous electrophysiological activity during both normal brain function and pathological states such as epileptic seizures. Understanding how the dynamics of neuronal oscillators in the brain evolve from normal to diseased states is a critical component towards decoding such complex behaviors. In my studies, I assessed multi-site dynamics underlying seizure evolution in limbic epilepsy by analyzing oscillators in recordings of local field potentials from three brain structures (bilateral hippocampi and anteromedial thalamus) in a rat model of temporal lobe epilepsy extracted using the empirical mode decomposition (EMD) technique. The analysis revealed patterns of multi-site phase coherence during initiation and termination phases of seizures. The multi-site synchrony events as seizures naturally terminated were used to model electrical deep brain stimulation (DBS) protocols aimed at stopping ongoing epileptic seizures. The location and frequency of the natural termination synchrony varied between subjects but was stable in time within each animal. My studies reveal that DBS protocols were significantly more effective at rapidly stopping seizures when the frequency and location of multi-site stimulation reflected the endogenous synchrony dynamics observed in each subject. These results strongly suggest that tailoring DBS protocols to individual endogenous rhythms that may represent how brains naturally resolve epileptic seizures could play a critical role in vastly improving the overall efficacy of this important therapy.
Ph.D. in Biomedical Engineering, December 2015
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