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- Title
- SURFACE CHARACTERIZATION OF NIOBIUM FOR SUPERCONDUCTING RF CAVITIES
- Creator
- Cao, Chaoyue
- Date
- 2014, 2014-07
- Description
-
Surface characterization techniques including point contact tunneling (PCT) spectroscopy and Raman spectroscopy have been employed to study...
Show moreSurface characterization techniques including point contact tunneling (PCT) spectroscopy and Raman spectroscopy have been employed to study the surface of niobium (Nb) superconducting radio frequency (SRF) cavities. PCT spectroscopy provides a direct means of measuring the surface superconductivity, which is closely correlated with the cavity’s performance characterized by the quality factor Q. Cavities with remarkably high Q show near ideal tunneling spectra with sharp coherent peaks and low zero bias conductance, consistent with the Bardeen-Cooper-Schrie↵er (BCS) density of states (DOS), and bulk gap parameter, " = 1.55 -1.6 meV. Cavities with Q-drop often exhibit strong non-uniform heating during RF operations, with high loss regions identified as hot spots. PCT spectra on hot spots reveal suppressed superconductivity, broadened DOS and Kondo tunneling, consistent with magnetic impurities on the surface. Raman spectra on hot spots indicate the presence of various impurities on the surface including amorphous carbon, C-H chain compounds and NbC, providing insights into the formation of hot spots. The origin of the impurities is unclear at present but it is suggested that particular processing steps in SRF cavity fabrication may be responsible.
Ph.D. in Physics, July 2014
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- Title
- Functionalized Polyoxovanadates: Synthesis, Characterization and Properties
- Creator
- Zheng, Yujuan
- Date
- 2012-04-30, 2011-12
- Description
-
The compound [NaVIV6O6{(OCH2CH2)2NCH2CH2OH}6]Cl.H20, designated C0 in this report, an Anderson type structure, contains a single nitrogen atom...
Show moreThe compound [NaVIV6O6{(OCH2CH2)2NCH2CH2OH}6]Cl.H20, designated C0 in this report, an Anderson type structure, contains a single nitrogen atom in place of a single oxygen atom in each of the six vanadium-oxygen octahedra. Attached to each nitrogen are two alkoxide arms (-O-C-C-) which terminate on separate oxygen atoms of the octahedra. A third ethoxy group (-CH2-CH2-OH) dangles freely from each nitrogen atom. The functionalized cationic core [NaVIV6O6{(OCH2CH2)2NCH2CH2OH}6]+ is generated in situ and is cationic with a charge of +1. Chloride is the counteranion. Each vanadium addenda atom is the +4 oxidation state, and the six unpaired electrons result in interesting magnetic properties. C0 is obtained by reaction of a vanadium oxide source triethanolamine. The purpose of the research described here was to adapt the synthetic protocol associated with triethanolamine to other similar ligands. Ligand choice was motivated by the broader goal of this research group to form (extended) hybrid electronic and magnetic materials by chemically bonding POM cores to chemically interesting ligands, such as dyes or other POM cores. In this regard, the original triethanolamine derivative has a number of shortcomings; chief among them is the inaccessibility of the alcoholic functional group chemistry---due to its low pH---that otherwise might have been used to form linkages through the dangling alkoxy arms. Additionally, linkages containing paraffinic carbon (-C-C-), which is not a good conduit of electronic interaction, are chemically undesirable where the synthetic goal is hybrid structures with interesting electronic and magnetic properties. The results associated with the three ligands, diethanolamine, N,N'-Bis(2-hydroxyethyl)ethylenediamine, and N,N-Bis(2-hydroxyethy) ethylenediamine, are described herein. Diethanolamine was chosen because---based on a structural comparison to triethanolamine---it was expected to produce a structure having a hydrogen atom in place of the dangling ethoxy arms, which was indeed the result. We considered this structure highly desirable becasue of the potential lability of the hydrogen atom (-N-H), which would allow us to functionalist the core directly. The resulting compounds are characterized by single-crystal X-ray diffraction, elemental analysis, mass spectroscopy, thermogravimetric analysis, FT-IR and UV-Vis spectroscopy, maganometric titration, temperature-dependent magnetic susceptibility measurements, and cyclic voltammetry. The results of the cyclicvoltammetric investigation are consistent with the labile hydrogen atom (-N-H).
M.S. in Chemistry, December 2011
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- Title
- MULTIPLE-INPUT MULTIPLE-OUTPUT NONLINEAR CONTROL OF SELECTIVE CATALYTIC REDUCTION SYSTEMS
- Creator
- Dong, Siwei
- Date
- 2015, 2015-05
- Description
-
Selective catalytic reduction (SCR) is one of the most promising solutions to meet the future nitrogen oxides (NOx) emissions regulations for...
Show moreSelective catalytic reduction (SCR) is one of the most promising solutions to meet the future nitrogen oxides (NOx) emissions regulations for heavy-duty diesel vehicles. However, such vehicles often operate in highly transient operations in which mobile selective catalytic reduction systems encounter significant efficiency challenges, especially when the engine is under a low load. A detailed simulation model of the SCR system was developed in the Gamma Technologies simulation suite and a baseline model of feedback control on SCR was constructed. Experiment data for the exhaust gas composition and conditions from a Cummins ISB engine was used to provide the input parameters for the SCR model. The results reveal that in the low-load conditions, the efficiency of NOx reduction in the SCR system is very low, and the level NOx concentration exiting the vehicle could be over 5 times than the limitation set by the US Environmental Protection Agency (EPA). However, these issues are encountered in part due to the fact that current SCR controls focus solely on the aftertreatment components and treat the incoming engine output conditions as system disturbances. To address the low NOx conversion problems encountered in low load conditions, a new integrated engine and aftertreatment control model was designed. This integrated approach improves the SCR system efficiency by using available feedback and modulating the upstream air/fuel ratio to provide more favorable SCR inlet conditions. From experiment data analysis, the engine’s air/fuel ratio is shown to have a critical impact on exhaust gas temperature and exhaust oxygen fraction, which highly affect the SCR reactions. In order to integrate the engine and aftertreatment system, a model of the SCR dynamics was created and validated and a simple model of the relationship between the engine’s air/fuel ratio and resulting exhaust temperature and composition is leveraged. The new model-based control strategy is proven to be effective to improve SCR system performance at low-load operations. With a small value shift in air/fuel ratio, the efficiency of low-load SCR system can increase from 40% to 85% at low load operating conditions.
M.S. in Mechanical and Aerospace Engineering, May 2015
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- Title
- Devices that Assist Blind & Visually-Impaired Individuals in Swimming and Other Exercise Activities (sequence unknown), IPRO 310 - Deliverables: IPRO 310 Midterm Presentation F09
- Creator
- Dykeman, Kimberly, Healton, Michaela, Lipman, Timothy, Ludwig, Ross, Park, Jay, Reilly, Jeffrey, Sarkar, Smita, Sirk, Phillip, Toro, Branden
- Date
- 2009-12
- Description
-
The objective is to develop, test, and implement assistive technology with the community that promotes safety and improves independence of...
Show moreThe objective is to develop, test, and implement assistive technology with the community that promotes safety and improves independence of blind and visually impaired (BVI) swimmers.
Sponsorship: Chicago Lighthouse for the Blind & Visually-Impaired. Notre Dame University
Deliverables for IPRO 310:Devices that Assist Blind & Visually-Impaired Individuals in Swimming and Other Exercise Activities for the fall 2009 semester.
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- Title
- LINEAR AND NONLINEAR BEHAVIOR OF TRANSIENT LIFT RESPONSE TO PULSE-ACTUATION
- Creator
- An, Xuanhong
- Date
- 2014, 2014-07
- Description
-
The transient lift coe cient for a NACA0009 airfoil with pulsed jet actuation type of active ow control at stall conditions is investigated....
Show moreThe transient lift coe cient for a NACA0009 airfoil with pulsed jet actuation type of active ow control at stall conditions is investigated. The experimental mea- surements show the lift coe cient dependence to a single-pulse with di erent pulse widths and amplitudes. Based on the single-pulse with optimal parameters, multi- pulse and continuous pulse actuation cases are studied, which indicate that the pulse interval is the major factor of the active ow control system capability. Linear and nonlinear model are used to predict the lift coe cient variation for di erent input signals to the actuators. A combined nonlinear model is introduced to predict lift coe cient change due to arbitrary unsteady pitching motion with active ow control.
M.S. in Mechanical and Aerospace Engineering, July 2014
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- Title
- BIG DATA SYSTEM INFRASTRUCTURE AT EXTREME SCALES
- Creator
- Zhao, Dongfang
- Date
- 2015, 2015-07
- Description
-
Rapid advances in digital sensors, networks, storage, and computation along with their availability at low cost is leading to the creation of...
Show moreRapid advances in digital sensors, networks, storage, and computation along with their availability at low cost is leading to the creation of huge collections of data { dubbed as Big Data. This data has the potential for enabling new insights that can change the way business, science, and governments deliver services to their consumers and can impact society as a whole. This has led to the emergence of the Big Data Computing paradigm focusing on sensing, collection, storage, management and analysis of data from variety of sources to enable new value and insights. To realize the full potential of Big Data Computing, we need to address several challenges and develop suitable conceptual and technological solutions for dealing them. Today's and tomorrow's extreme-scale computing systems, such as the world's fastest supercomputers, are generating orders of magnitude more data by a variety of scienti c computing applications from all disciplines. This dissertation addresses several big data challenges at extreme scales. First, we quantitatively studied through simulations the predicted performance of existing systems at future scales (for example, exascale 1018 ops). Simulation results suggested that current systems would likely fail to deliver the needed performance at exascale. Then, we proposed a new system architecture and implemented a prototype that was evaluated on tens of thousands nodes on par with the scale of today's largest supercomputers. Micro benchmarks and real-world applications demonstrated the e ectiveness of the proposed architecture: the prototype achieved up to two orders of magnitude higher data movement rate than existing approaches. Moreover, the system prototype was incorporated with features that were not well supported in conventional systems, such as distributed metadata management, distributed caching, lightweight provenance, transparent compression, acceleration through GPU encoding, and parallel serialization. Towards exploring the proposed architecture at millions of node scales, simulations were conducted and evaluated with a variety of workloads, showing near linear scalability and orders of magnitude better performance than today's state-of-the-art storage systems.
Ph.D. in Computer Science, July 2015
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- Title
- Some commutation phenomena of direct current machinery
- Creator
- Clark, F. C.
- Date
- 2009, 1905
- Publisher
- Armour Institute of Technology
- Description
-
http://www.archive.org/details/somecommutationp00clar
Thesis (B.S.)--Armour Institute of Technology
- Title
- DESIGN OF RESILIENT CONTROLLABLE CHEMICAL PROCESSES - AN AUTOTHERMAL REACTOR CASE-STUDY
- Creator
- Chylla, R. W., Cinar, A.
- Date
- 1990-07
- Publisher
- AMER CHEMICAL SOC
- Description
-
A technique for the analysis of state-space linear systems is applied to the problem of selection of resilient chemical process designs....
Show moreA technique for the analysis of state-space linear systems is applied to the problem of selection of resilient chemical process designs. Structural Dominance Analysis affords the evaluation of many process design and control configurations and assessment of the effects of potential manipulated variables and disturbances. After a brief presentation of the analysis method, a complex multibed tubular autothermal reactor system is examined. Resilient process configurations, ease of control, and effects of various inputs on reactor state variables and outputs are considered, and effective control configurations are selected.
Endnote format citation
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- Title
- OPTIMIZATION OF POWER TRENCH MOSFETS FOR HIGH EFFICIENCY SYNCHRONOUS BUCK CONVERTERS
- Creator
- Wang, Wendi
- Date
- 2016, 2016-05
- Description
-
Synchronous buck converter might be one of the most widely used and fabricated circuitry in the world for its favorable trade-off on many...
Show moreSynchronous buck converter might be one of the most widely used and fabricated circuitry in the world for its favorable trade-off on many subjects. However, the ever higher operation frequency has lead to increasing power loss in power switches and imposed new challenge to MOSFET engineering. One promising alternative for the traditionally used trench MOSFET is the shield gate MOSFET. Shield gate MOSFET has superior conduction performance as well as fast switching transient response due to its Reduced Surface Electric Field (RESURF) effect. In recent years, characterization of power MOSFET has developed along with MOSFET technology itself. New Figure of Merits (FOMs) have come into people's sight as they serve as better standards to fully describe MOSFET's overall performance. Being the same case for many other device structures, this new characterizing system also puts advanced requirements to shield gate MOSFET. And one of the most crucial problems is the rather large output capacitance this structure is having. To improve the property of shield gate MOSFET and meet the requirements of new standards, several ways of structure refinement have been proposed in this work. Both shield gate MOSFET and conventional MOSFET rated at 40V have been designed and simulated in the second chapter. The outcome shows that shield gate MOSFET has superior performance in almost every respect except for its large output charge. Then new structure for COSS reduction has been introduced in the following section, with decrement of about 50% in QQS-1 being achieved. Finally, another issue that has been tackled with is the shoot through of synchronous buck converter. Equivalent circuit model for shoot through analysis is built in this section to study the effect of each parasitic element. And a p type pillar added structure has been verified as an effective way to suppress shoot through gate bounce.
M.S. in Electrical Engineering, May 2016
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- Title
- Reuse of 1230 N. Burling | Cabrini Green Youth Center
- Creator
- Ciorba, Dan
- Date
- 5/4/2011, 2011-05
- Description
-
Demolishing a concrete building that is structurally sound is ecologically wasteful and irresponsible. With the many advantages concrete...
Show moreDemolishing a concrete building that is structurally sound is ecologically wasteful and irresponsible. With the many advantages concrete offers and rising energy costs, there needs to be a way that existing and structurally sound, concrete buildings can be reused. This explored method for concrete reuse depends heavily on technological advances in the foreseeable future that allow for the process to be accomplished efficiently and for the material to be preserved for a longer period of time.
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- Title
- Searching for W' bosons at LHC with single top production, Proceedings of the XLIII International Symposium on Multiparticle Dynamics
- Creator
- Duffty, Daniel, Sullivan, Zack
- Date
- 2013-09-15, 2013-09-15
- Publisher
- IIT Press
- Description
-
One of the strengths of the LHC is its capacity for the discovery of new physics. As a consequence of many BSM theories, W′ bosons make an...
Show moreOne of the strengths of the LHC is its capacity for the discovery of new physics. As a consequence of many BSM theories, W′ bosons make an ideal particle to search for to constrain many models. One mode in particular has relatively low background: Single top quark production mediated by a W′ boson. For W′ masses less than 1500 GeV, all the decay products of the top quark are visible, and the strongest channel is the top’s decay into an electron or muon, with the associated neutrino and a bottom jet. As the W′ mass increases, the decay products from the highly boosted top and bottom quarks from the W′ appear as fat jets; boosted top tagging algorithms abound, and we propose a boosted bottom tag to set an exclusion limit of 2750 GeV for standard model-like couplings with existing 8 TeV data.
Sponsorship: IIT College of Science, High Energy Physics Division of Argonne National Laboratory
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- Title
- BIO-COMPOSITE NANOMATERIALS; CHARACTERIZATION, MANIPULATION AND APPLICATION
- Creator
- Kim, Taeyoung
- Date
- 2013, 2013-05
- Description
-
Biomaterials are any matter or material which interacts with biological system which were present on natural or synthetic nonviable materials....
Show moreBiomaterials are any matter or material which interacts with biological system which were present on natural or synthetic nonviable materials. An ideal biomaterial must physically and chemically compatible for biological applications to avoid toxicity and immune reaction. Collagen is a widely abundant, robust biopolymer that is found in the extracellular matrix (ECM) of many tissues. In terms of its structure and organization, collagen is a bio-nano material. The use of collagen in stem cell differentiation is particularly enticing since it is now evident that the extracellular matrix (ECM) proteins can regulate the cell’s fate and growth by their molecular and physical properties. In this thesis research, we have characterized the physical and structural properties of collagen and its composite materials. We found collagen interacts with NaCl and other nano-materials, such as carbon nanotube (CNT) and TiO2 nanotube, resulting in the modification of collagen structure and increase of its stiffness. In particular, CNT has changed collagen structure at both the molecular level and the higher organizational level. The effects of the matrices on cell growth and development were studied. It was found that collagen/CNT matrix specify and accelerate the stem cell differentiation toward neural cells. Since neurons form the foundation of biological circuit, manipulation of neurons in growth has the potential to form desired biological circuit. We also examined collagen in vaginal wall connective tissues, and found that alteration of collagen properties in clinical tissues is correlated to the onset of pelvic organ prolapse.
PH.D in Chemistry, May 2013
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- Title
- FoodLab - A revitalization strategy for the Pari yard, Sao Paulo - Brazil
- Creator
- Lussich Garese, Maria Fernanda
- Date
- 5/4/2011, 2011-05
- Description
-
This project aims to develop a new design strategy to redevelop the Pari yard and reclaim the adjacent Tamanduatei river by turning it into an...
Show moreThis project aims to develop a new design strategy to redevelop the Pari yard and reclaim the adjacent Tamanduatei river by turning it into an operative landscape. A holistic system to harverst, clean and reuse the abundant summer rainfall was created in order to enable a highly sustainable urban redevelopment.
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- Title
- Feedback control of a continuous-flow stirred tank reactor with competing autocatalators
- Creator
- Chaivorapoj, W., Birol, I., Cinar, A., Teymour, F.
- Date
- 2003-08-06
- Publisher
- AMER CHEMICAL SOC
- Description
-
Two types of nonlinear feedback control schemes are introduced and analyzed for their capability of recovering the original state of an...
Show moreTwo types of nonlinear feedback control schemes are introduced and analyzed for their capability of recovering the original state of an isothermal continuous-flow stirred tank reactor with one robust cubic autocatalytic species, perturbed by a temporary disturbance of an invading cubic autocatalytic species in the inflow. The control objectives are to eliminate the invading species from the system and to restore the original state of the host species. The extent of applicability of the control design to different nonrobust invading species is studied, when the controller is tuned for a specific invader. Moreover, a time-delay feature is suggested in one of the control schemes developed to achieve the control objectives in systems with poor detection of invading species.
Endnote format citation for DOI:10.1021/ie020427+
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- Title
- Some features of a modern overhead distributing system
- Creator
- Redman, A. R.
- Date
- 2009, 1916
- Publisher
- Armour Institute of Technology
- Description
-
http://www.archive.org/details/somefeaturesofmo00redm
Thesis (B.S.)--Armour Institute of Technology
- Title
- Washington Park Center for Improvisational Music: Kellen White_FINAL 34x44 BOARD_02
- Creator
- White, Kellen
- Date
- 2010-07-30
- Title
- the evolution of the south fork turning basin: Grilli_Preliminary_Research
- Creator
- Grilli, Graham
- Date
- 5/4/2011, 2011-05
- Description
-
a historical analysis of the South Fork Turning basin from 1833-2040 including proposals for future timeline. wetland remediation coupled with...
Show morea historical analysis of the South Fork Turning basin from 1833-2040 including proposals for future timeline. wetland remediation coupled with modular housing and adaptive reuse solutions. prototype for other potential developments along river's edge leading to healthier Great Lakes basin.
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- Title
- Defining the Role of the 21st Century Public Library in Madison: Bartley_N_MadisonLibrary_Final_Board
- Creator
- Bartley, Nate
- Date
- 2011, 2011-05
- Description
-
Madison, WI is dominated by two main forces; the state government and the University of Wisconsin. These two institutions are linked by State...
Show moreMadison, WI is dominated by two main forces; the state government and the University of Wisconsin. These two institutions are linked by State Street, a pedestrian and bike corridor that serves as the main public gathering space for the city. The new Central Public Library along this strip will provide a free, democratic space for all Madison citizens. Beyond collecting books and storing media, the Madison Library offers opportunities for gatherings and informational exchanges 24 hours a day.
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- Title
- Cure for the IKIA Syndrome : presented at IACRL 2008 conference: 08Final_Schedule
- Creator
- Uth, Charles, Link, Jeanne
- Date
- 2008-02
- Description
-
Informal observations of a practical and creative approach piloting Blended Library Instruction for undergraduate Civil Architecture and...
Show moreInformal observations of a practical and creative approach piloting Blended Library Instruction for undergraduate Civil Architecture and Engineering students, in collaboration with faculty. At Illinois Institute of Technology students don’t receive library instruction as a required class or in tandem with a composition class. Faculty will schedule one-time sessions, which ideally should be planned with a class assignment in mind, but students are rarely engaged with a one time instruction. Many have IKIA syndrome or I Know It Already syndrome. The Millennials are a group that has integrated technology into every aspect of their lives and they assume that retrieving useful or necessary information will be easy. When they discover this isn’t the case lack of time, heightened anxiety, and increased frustration can prevent them from doing their best work. By intentionally creating a similar crisis prior to library instruction, students were more interested in what they stood to gain during pending library instruction. In this presentation we will discuss: 1) A creative means of delivering library instruction to a traditionally challenging population: engineering undergraduate students 2) Qualitative information collected via multiple assignments and interpreted in a quantitative fashion, as well as our observations. 3) A method for preparing students for library instruction that can be applied in almost any discipline without asking the instructor to sacrifice class time.
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- Title
- PROBING THE PAN-GENOME OF LISTERIA MONOCYTOGENES
- Creator
- Deng, Xiangyu
- Date
- 2011-04-26, 2011-05
- Description
-
Bacterial pathogens often show significant intra-species variations in ecological fitness, host preference and pathogenic potential to cause...
Show moreBacterial pathogens often show significant intra-species variations in ecological fitness, host preference and pathogenic potential to cause infectious disease. The species of Listeria monocytogenes, a facultative intracellular pathogen and the causative agent of human listeriosis, consists of at least three distinct genetic lineages. Two of these lineages predominantly cause human sporadic and epidemic infections, whereas the third lineage has never been implicated in human disease outbreaks despite its overall conservation of many known virulence factors. The genomes of 26 L. monocytogenes strains representing the three lineages are compared based on both in silico comparative genomic analysis and high-density, pan-genomic DNA microarray hybridizations. We uncover 86 genes and 8 small regulatory RNAs that likely make L. monocytogenes lineages differ in carbohydrate utilization and stress resistance during their residence in natural habitats and passage through the host gastrointestinal tract. We also identify 2,330 to 2,456 core genes that define this species along with an open pan-genome pool that contains more than 4,052 genes. Phylogenomic reconstructions based on 3,560 homologous groups allowed robust estimation of phylogenetic relatedness among L. monocytogenes strains. The pan-genome approach enables accurate co-analysis of DNA sequence and hybridization array data for both core gene estimation and phylogenomic reconstruction. Application of our method to the pan-genome of L. monocytogenes sheds new insights into the intra-species genomic diversification, niche expansion and evolution of this important foodborne pathogen.
Ph.D. in Biology, May 2011
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