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(501 - 520 of 4,071)
Pages
- Title
- Shock-induced Flow Resonance in Supersonic Jets of Complex Geometry
- Creator
- Raman, G.
- Date
- 1999-03
- Publisher
- American Inst Physics
- Description
-
Jets with complex shock-cell structures exist in numerous technological applications. This paper describes a fundamental study of shock...
Show moreJets with complex shock-cell structures exist in numerous technological applications. This paper describes a fundamental study of shock-induced flow resonance (commonly referred to as "jet screech") in supersonic jets with spanwise nonuniform shock-cell structures. Experiments that involve flow visualization and detailed mapping of the near field reveal unsteady aspects of shock-induced flow resonances, mode transitions, and directivity of the radiated noise. The following important results about the role of spanwise nonuniform shock-cells emerged: (1) It is possible to have two coexisting, independent feedback loops at nonharmonically related frequencies and different spanwise modes. (2) The same type of spanwise asymmetric mode was produced by two entirely different source configurations. (3) Nozzle geometry significantly altered the intensity and directivity of screech and broadband shock noise. The results presented here provide considerable insight into the fluid dynamics and acoustics of jets with spanwise oblique shock-cell structures and provide grounds for believing that shock-induced noise can be controlled by tailoring nozzle geometry. (C) 1999 American Institute of Physics. [S1070-6631(99)00103-8].
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- Title
- STUDY ON EX POST PRICING
- Creator
- Zhao, Zhechong
- Date
- 2011-05-02, 2011-05
- Description
-
The main objective of this thesis is to study the ex post pricing in electricity market by implementing two new methods (quantity based method...
Show moreThe main objective of this thesis is to study the ex post pricing in electricity market by implementing two new methods (quantity based method and price based method). The quantity based method measures the difference between the actual performance of an individual resource and its bid-based profit-maximizing response to the ex post prices. The price based method measures the different between the ex post price and the supporting price which supports the actual outputs. These two methods are based on a co-optimization market for energy and ancillary service. They are very flexible and can solve the ex post price efficiently and simultaneously.
M.S. in Electrical Engineering, May 2011
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- Title
- COMPARATIVE GENOMICS OF STREPTOCOCCUS SALIVARIUS ATCC 27945 AND 25975; FROM HELPFUL TO HARMFUL?
- Creator
- Soomer-james, Jahna T. A.
- Date
- 2015, 2015-07
- Description
-
Streptococcus salivarius is a commensal bacterium that normally inhabits the oral mucosa. However, preliminary data indicated that the strain...
Show moreStreptococcus salivarius is a commensal bacterium that normally inhabits the oral mucosa. However, preliminary data indicated that the strain ATCC 25975 has acquired parasitic genes from Streptococcus pneumoniae. To investigate the nature of this genetic exchange, the genome of Streptococcus salivarius ATCC 27945 was first sequenced and served as a comparative model to provide insight into the possibility of development of pathogenicity within the salivarius group. Illumina and PacBio sequencing data were used complementarily to generate reliable genomes of the Streptococcus salivarius ATCC 27945 and ATCC 25975 strains. The reads were trimmed, filtered, assembled and annotated using custom Perl scripts and various software. The completed genomes of S. salivarius ATCC 27945 and ATCC 25975 are 2.11 Mbp and 2.20 Mbp long, respectively, with ATCC 25975 featuring an additional plasmid. Comparative genomics with other sequenced salivarius genomes revealed that strain ATCC 27945 was most closely related to strains JIM8777 and NCTC8618, while strain ATCC 25975 was more closely related to strains 57I and CCHSS3. The proteins that were common across the investigated salivarius genomes included housekeeping proteins involved in pathways such as DNA replication, metabolism and DNA repair but the unique protein types and their relative location to each other within the ATCC main chromosomes did not provide conclusive evidence to the identification of the parasitic cassette. However, the plasmid contained in S. salivarius ATCC 25975 showed promising signs of containing these genes of interest. Several genes typically found in S. pneumoniae such as capsular polysaccharide genes and two copies of integrative and conjugative genes were identified in close proximity. The phylogenetic analysis of the two S. salivarius ATCC strains suggested that the proposed genes acquired from S. pneumoniae might have been gained via horizontal gene transfer rather than through sporadic mutations. The plasmid had a 5.1% smaller GC content compared to the other salivarius chromosomes, further suggesting that it was acquired from a distinct organism. Overall, while these results provided useful insights into the nature and location of the parasitic cassette, further investigations will be required to assess the full extent of the genetic shuffling that occurred by horizontal gene transfer in these Streptococcus species.
M.S. in Biology, July 2015
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- Title
- A study of anti-friction lineshaft bearings
- Creator
- Katzinger, Arthur, Alte, Arthur S.
- Date
- 2009, 1916
- Publisher
- Armour Institute of Technology
- Description
-
http://www.archive.org/details/studyofantifrict00katz
Thesis (B.S.)--Armour Institute of Technology; Bibliography: leaves 212-220
- Title
- Delta Shelter (sequence unknown), IPRO 311 - Deliverables: IPRO 311 Midterm Presentation F09
- Creator
- Schug, Timothy, Bradley, Joshua, Cahan, Noah, Dobbin, Dan, Hallenbeck, Jeff, Jordan, Davyd, Strandquist, Brad, Dohm, Jacob, Hoffman, Kent, Lee, Woong-kyo, Waisath, Nathan
- Date
- 2009-12
- Description
-
The Delta Tau Delta fraternity wants to make their current house as energy efficient and green as possible. The team will look at all aspects...
Show moreThe Delta Tau Delta fraternity wants to make their current house as energy efficient and green as possible. The team will look at all aspects of the DTD house and their operations to create a more energy efficient fraternity. During the term, the team will consider possible alternatives to many issues including but not limited to: mechanical heating system, building envelope, thermal properties of buildings perimeter, roofing materials, air infiltration, ventilation, and occupancy trends.
Deliverables for IPRO 311: Delta Shelter for the fall 2009
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- Title
- Resonant interaction of a linear array of supersonic rectangular jets: An experimental study
- Creator
- Raman, G, Taghavi, R
- Date
- 1996-11-10
- Publisher
- CAMBRIDGE UNIV PRESS
- Title
- ORGANIZATIONAL FLEXIBILITY IN CONSTRUCTION COMPANIES
- Creator
- Taghizadeh Khamesi, Hossein
- Date
- 2016, 2016-05
- Description
-
Flexibility is a key factor for an organization survival in a changing environment. Considering the cyclical nature of construction demand,...
Show moreFlexibility is a key factor for an organization survival in a changing environment. Considering the cyclical nature of construction demand, organizational flexibility is of special importance in construction company management. Most previous studies tried to categorize the response strategies of construction contractors to business and environmental changes. However, there is gap in the literature about the dynamic effect of organizational flexibility on the growth and competitiveness in construction companies. The objective of this study is to investigate the organizational flexibility of top construction contractors in the U.S. Engineering News-Records (ENR) top 400 contractors lists were used to collect data for the 52-year period 1963-2015. Using the collected data, several analyses were performed to find the relationship between organizational flexibility and competitive success. This attempt did not indicate a distinct relationship between organizational flexibility and competitiveness. It was found however that organizational flexibility is affected by change in the economy and that it was linked to company expansion/contraction. It is concluded that organizational flexibility is an essential advantage for construction contractors. Those contractors that are consistently ranked in the top 400 contractors list respond well to economic changes by expanding and contracting. On the other hand, different size contractors respond to changes in the economy differently, based on their resources and the nature of their work. In addition, this study concluded that those contractors that seek high growth rates face more fluctuations in their growth path and need more flexibility in response to them.
M.S. in Civil Engineering, May 2016
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- Title
- Buffalo Food Path
- Creator
- Huttel, Anna
- Date
- 2010-07-29
- Title
- HOT DUCTILITY BEHAVIOR IN THE CONTINUOUS CASTING OF NIOBIUM-BEARING MICROALLOYED STEELS
- Creator
- Jansto, Steven George
- Date
- 2013, 2013-12
- Description
-
Over 200 million tons of Niobium-bearing steels were continuously cast and hot rolled globally in 2012. These Nb-bearing plate, bar and sheet...
Show moreOver 200 million tons of Niobium-bearing steels were continuously cast and hot rolled globally in 2012. These Nb-bearing plate, bar and sheet products are manufactured throughout the world. The melting and casting practices to assure production of crack-free slabs, billets and blooms of high surface quality is presented. Much has been published about the traditional ductility trough associated with higher carbon equivalent steels with and without microalloy additions of Nb, V and/or Ti. The focus has primarily been on the chemistry and optimal composition based upon the literature review. However, the steelmaking and process metallurgy parameters are rarely correlated to the hot ductility behavior. Most studies involve laboratory produced heats, but this research is based upon industrial produced samples.The hot ductility troughs associated with simple carbon-manganese steels can also result in surface and internal quality issues if certain steelmaking and casting parameters are not followed. Although high carbon equivalent steels exhibit inherently lower hot ductility behavior, as measured by percent reduction in area at elevated temperature, these steels still exhibit sufficient ductility to satisfactorily meet the unbending stress and strain gradients existing in the straightening section of most casters. The % Reduction in Area significantly overstates the minimum ductility required for crack-free casting of Nb-bearing steels. The relationship between the steelmaking and caster operation and the resultant slab quality is related through the hot ductility behavior. This global Nb-bearing continuous casting steel research study introduces the strain energy as an improved xxi measure of the hot ductiity behavior. The incidence of cracking is primarily related to the steelmaking and caster process parameters and steel chemistry is secondary. These parameters include the elemental residual chemistry level, superheat variation, transfer ladle temperature stratification, oscillation frequency and stroke, mould flux incompatibility, casting speed fluctuation, and excessive secondary cooling.
PH.D in Materials Science and Engineering, December 2013
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- Title
- INITIAL TURBULENCE EFFECT ON JET EVOLUTION WITH AND WITHOUT TONAL EXCITATION
- Creator
- Raman, G, Zaman, Kbmq, Rice, Ej
- Date
- 1989-07
- Publisher
- AMER INST PHYSICS
- Title
- The study and design of spray nozzles as applied to the De La Vergne oil engine
- Creator
- Harman, William E. S, Ward, Fred L
- Date
- 2009, 1915
- Publisher
- Armour Institute of Technology
- Description
-
http://www.archive.org/details/studydesignofspr00harm
Thesis (B.S.)--Armour Institute of Technology; Bibliography: leaf 2
- Title
- UNDERSTANDING UNCERTAINTIES IN RESOLVED PHOTON STRUCTURE
- Creator
- Zhan, Hengrui
- Date
- 2017, 2017-07
- Description
-
The construction of a photon collider has been urged, in order to study the properties of the Higgs boson and electroweak symmetry breaking....
Show moreThe construction of a photon collider has been urged, in order to study the properties of the Higgs boson and electroweak symmetry breaking. It would also provide unique possibilities for measurement of fusion to probe the hadronic structure of the photon. One scheme of design for the photon collider is a linear collider. A study shows that resolved photons contribute about 15% of the cross section to Higgs production with a mass of 120 GeV, but estimates of the resolved photon structure have so far varied greatly. Therefore, resolved photon structure is important to measure. This thesis focuses on the determination of the uncertainties of the cross section of bb production for better understanding of resolved photon structure. The principles of a photon collider are reviewed. In this thesis, the simulation tools for the simulation of the cross section of ! bb collision are developed. After that, the method for determination of the uncertainties of cross section is described. A new set of PDFs to explore these uncertainties is produced. The result of the simulation of the cross section and the calculation for the uncertainties of the cross section is presented and discussed in detailed.
M.S. in Physics, July 2017
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- Title
- PRICING AND APPLICATION OF ELECTRIC STORAGE
- Creator
- Zhao, Jialin
- Date
- 2017, 2017-05
- Description
-
Electric storage provides a vehicle to store power for future use. It contributes to the grids in multiple aspects. For instance, electric...
Show moreElectric storage provides a vehicle to store power for future use. It contributes to the grids in multiple aspects. For instance, electric storage is a more effective approach to provide electricity ancillary services than conventional methods. Additionally, electric storage, especially fast-responding units, allows owners to implement high-frequency power transactions in settings such as the 5-min real-time trading market. Such high-frequency power trades were limited in the past. However, as technology advances, the power markets have evolved. For instance, the California Independent System Operator now supports the 5-min real-time trading and the hourly day-ahead ancillary services bidding. Existing valuation models of electric storage were not designed to accommodate these recent market developments. To fill this gap, I focus on the fast-responding grid-level electric storage that provides both the real-time trading and the day-ahead ancillary services bidding. To evaluate such an asset, I propose a Monte Carlo Simulation-based valuation model. The foundation of my model is simulations of power prices. This study develops a new simulation model of electric prices. It is worth noting that, unlike existing models, my proposed simulation model captures the dependency of the real-time markets on the day-ahead markets. Upon such simulations, this study investigates the pricing and the application of electric storage at a 5-min granularity. Essentially, my model is a Dynamic Programming system with both endogenous variables (i.e., the State-of-Charge of electric storage) and exogenous variables (i.e., power prices). My first numerical example is the valuation of a fictitious 4MWh battery. Similarly, my second example evaluates the application of two units of 2MWh batteries. By comparing these two experiments, I investigate the issues related to battery configurations, such as the impacts of splitting storage capability on the valuation of electric storage.
Ph.D. in Management Science, May 2017
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- Title
- COMPUTATIONAL FLUID DYNAMICS AND POPULATION BALANCE MODEL FOR SIMULATION OF DRY SORBENT BASED CO2 CAPTURE PROCESS
- Creator
- Abbasi, Emadoddin
- Date
- 2013, 2013-12
- Description
-
Carbon capture and sequestration (CCS) is one of the key technologies needed to mitigate carbon dioxide emission from industrial sources and...
Show moreCarbon capture and sequestration (CCS) is one of the key technologies needed to mitigate carbon dioxide emission from industrial sources and power plants. Development of CFD-based design tool for prediction of the extent of CO2 capture in a regenerable dry sorbent-based technology, in an efficient power plant design (i.e., modern IGCC power plants) was the driving force behind this project. In this study, we established a systematic methodology, starting from investigating the properties of the sorbent and its reaction mechanism, to developing a model for design and scale-up of the reactors that is needed to deploy this technology at larger scales. This dissertation provides a coupled CFD-PBE model based on the novel FCMOM approach with broad application in reaction engineering and reactor design where the polydisperse nature of the phases has strong effect on the hydrodynamics of the system. Detailed investigations of the MgO-based sorbent and its performance toward capturing CO2 from a coal gas stream were performed that result in development of the two-zone variable diffusivity shrinking core reaction model. Furthermore, a baseline design for a circulating fluidized bed (CFB) reactor, using numerical modeling and threedimensional simulations of a full-loop circulating fluidized bed reactor was provided based on the coupled CFD-PBE, which in combination with the reaction model can perform as a base for parametric studies and optimization of the process.
PH.D in Chemical Engineering, December 2013
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- Title
- AN INTRINSICALLY CONDUCTING POLYMER-BASED COATING SYSTEM FOR CORROSION PROTECTION OF STEELS
- Creator
- Yu, Qifeng
- Date
- 2016, 2016-12
- Description
-
Among the various corrosion protection strategies for structural steels, coating techniques provide the most cost-effective protection and...
Show moreAmong the various corrosion protection strategies for structural steels, coating techniques provide the most cost-effective protection and have been used as the primary mode for corrosion protection. Existing coating techniques have been used mainly for their barrier capability and all have a limited service life. In this research work, a waterborne two-strand polyaniline: poly (acrylic acid) complex was synthesized and utilized to fabricate the primer layer of a two-layer coating system. The techniques of Scanning Kelvin Probe Force Microscopy (SKPFM) and Electrochemical Impedance Spectroscopy (EIS) were used to evaluate the anti-corrosion capability of the polymeric complex when mixed in an epoxy matrix and coated on steel samples as the primer layer. The evaluation results show that coating systems including a PANi-based primer has measurable anticorrosion capability and the anti-corrosion capability of PANi-based primer depends on the usage of PANi and the type of matrix material of the primer layer. In the laboratory condition, a prototype two-layer coating system including the PANi-based primer and a polyurethane topcoat was manufactured. The ASTM Salt-Spray Test and EIS were used to prove the anti-corrosion performance of the prototype using a two-layer, polyurethane-over-epoxy system (no PANi) as the control system. After the proof of concept, a non-waterborne epoxy was used to fabricate a different PANi-based primer. The two types of primers and two other commercial primers (a zinc-rich primer and an epoxy-only primer) were used to make a total of eight two-layer coating systems using two widely used topcoats. Salt-Spray Test, Cyclic Salt Fog/UV Exposure Test, Pull- Off Adhesion Test, and the techniques of EIS, SKPFM, and Scanning Electron Microscope (SEM) were used to evaluate the long-term performance of the eight systems. Based on the laboratory-based recommendations, six groups of two-layer coating systems were then subjected to the outdoor-exposure test to evaluate their anti-corrosion durability at two testing sites. The field durability of the coating systems was evaluated in terms of their surface gloss reduction, color change, adhesion change and surface deteriorations. The matrix material in which the PANi is mixed plays an important role in the longterm anti-corrosion performance of coatings. The waterborne epoxy is effective in dispersing PANi nano-particles and has zero VOC; however, it does not bond to the steel surface as strongly as the regular non-waterborne epoxy. The topcoat material also plays an important role in the long-term anti-corrosion performance of coatings; polyurethane has higher durability than epoxy as a topcoat material. The PANi-based systems possess long-term corrosion protection comparable to the performance of the conventional zincrich three-layer system based on the one-year field evaluation.
Ph.D. in Civil Engineering, December 2016
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- Title
- Our Energy Future: Lessons in Sustainability AND IPRO Teams for K-12: The Education Outreach Service Learning Cluster (sequence unknown), IPRO 332 - Deliverables
- Creator
- Chavez, Jorge, Johnson, Ross, Chin, Jason, Grande, Gina, Lay, Livia, Mccloat, Declain, Nguyen, Nam, Olechno, Patrick, Randle, Jennifer, Tyler Ii, Micheal, Vega, Mayra, Weiner, Andrew, Zajac, Gregory
- Date
- 2009-12
- Description
-
The mission of the IPRO is to educate the community, focusing mainly on elementary and high school students, on the issues of sustainability...
Show moreThe mission of the IPRO is to educate the community, focusing mainly on elementary and high school students, on the issues of sustainability and energy conservation. The group looks to expand on the work that has been completed in previous semesters, by adding multi-media presentations to enhance the current teaching modules. Previous modules have presented to classrooms simply with information, and the team looks to add upon this by adding interactive and entertaining materials to intrigue the audience.
Deliverables for IPRO 332: IOur Energy Future: Lessons in Sustainability AND IPRO Teams for K-12: The Education Outreach Service Learning Cluster for the fall 2009 semester
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- Title
- DISCONTINUOUS IN THE NI-CO-AL PRECIPITATION ALLOY SYSTEM
- Creator
- Liu, Tian
- Date
- 2014, 2014-05
- Description
-
The synthesis of nanoplates of 0 by use of discontinuous precipitation was investigated in the Ni-Co-Al alloy system. A series of experiments,...
Show moreThe synthesis of nanoplates of 0 by use of discontinuous precipitation was investigated in the Ni-Co-Al alloy system. A series of experiments, such as heat treatment, cold rolling, and electrolytic etching, have been performed to develop the desired microstructure. Nanostructured materials have great potential in a number of applications, such as catalysis, light weight structural materials, thermal management and pollution reduction. Kinetic information of the Ni-Co-Al alloy was obtained through measuring the optical micrographs of samples aged at di erent temperatures. The morphology of the nanostructure of the Ni-Co-Al alloy was investigated using scanning electron microscopy (SEM). The mechanical property (hardness) of the Ni-Co-Al alloy was obtained in di erent conditions as well. The Ni-Co-Al alloys were recrystallized in di erent ways. The texture of the alloys were determined using electron backscattered di raction (EBSD). After analyzing those experimental results, we nd that the discontinuous precipitation goes to completion in the Ni-Co-Al alloy. The discontinuous precipitates present a lamellar structure. The size of plates is similar with the spacing between plates and achieves a nanoscale architecture. The TTT curve of the Ni-Co-Al alloy with a composition of 43 at.% Ni, 48 at.% Co and 9 at.% Al provides abundant kinetic information. Further work is needed to produce a strong cube texture ((100) planes parallel to the foil surface).
M.S. in Materials Engineering, May 2014
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- Title
- Using Assessment Data to Improve Library Services : presented at ILA 2007 conference: ILA_presentation_07_revised_final: ILA_presentation_07_revised_final
- Creator
- Stewart, Christopher, Uth, Charles
- Date
- 2007-10
- Description
-
IIT Libraries conducted LibQUAL+ service quality assessment in 2004 and 2006. This presentation will outline strategies we undertook to...
Show moreIIT Libraries conducted LibQUAL+ service quality assessment in 2004 and 2006. This presentation will outline strategies we undertook to address issues identified in the 2004 assessment, and evaluate their success based on assessment results in 2006. We will also discuss the importance of measuring academic library effectiveness in higher education’s emerging outcomes-based culture.
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- Title
- HERAFitter - an open source QCD fit framework, Proceedings of the XLIII International Symposium on Multiparticle Dynamics
- Creator
- Starovitov, Pavel
- Date
- 2013-09-15, 2013-09-15
- Publisher
- IIT Press
- Description
-
The patron distribution functions (PDFs) describe the parton content of the proton. They cannot be calculated from the first principle and are...
Show moreThe patron distribution functions (PDFs) describe the parton content of the proton. They cannot be calculated from the first principle and are to be determined empirically by fitting experimental observables to quantum chromodynamics (QCD) predictions. The HERAFitter project aims to provide a framework for QCD analyses of proton structure at leading order (LO), next-to-leading order (NLO) and next-to-next-to-leading (NNLO) orders in perturbative QCD. The framework includes various modules and interfaces enabling a large number of theoretical and methodological options. It also allows to study the impact of the new experimental data on the PDFs from ep, pp and pp̅ scattering processes. The fast development of the project involves active communication with theorists and experimentalist as well as a close collaboration with the main PDF fitting groups. Full information about the project, downloads and documentation can be found in http://herafitter.org.
Sponsorship: IIT College of Science, High Energy Physics Division of Argonne National Laboratory
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- Title
- Our Energy Future: Lessons in Sustainability AND IPRO Teams for K-12: The Education Outreach Service Learning Cluster (sequence unknown), IPRO 332 - Deliverables: Project Plan F09
- Creator
- Chavez, Jorge, Johnson, Ross, Chin, Jason, Grande, Gina, Lay, Livia, Mccloat, Declain, Nguyen, Nam, Olechno, Patrick, Randle, Jennifer, Tyler Ii, Micheal, Vega, Mayra, Weiner, Andrew, Zajac, Gregory
- Date
- 2009-12
- Description
-
The mission of the IPRO is to educate the community, focusing mainly on elementary and high school students, on the issues of sustainability...
Show moreThe mission of the IPRO is to educate the community, focusing mainly on elementary and high school students, on the issues of sustainability and energy conservation. The group looks to expand on the work that has been completed in previous semesters, by adding multi-media presentations to enhance the current teaching modules. Previous modules have presented to classrooms simply with information, and the team looks to add upon this by adding interactive and entertaining materials to intrigue the audience.
Deliverables for IPRO 332: IOur Energy Future: Lessons in Sustainability AND IPRO Teams for K-12: The Education Outreach Service Learning Cluster for the fall 2009 semester
Show less