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(501 - 520 of 4,680)
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- Title
- Flow characteristics of a rectangular multielement supersonic mixer-ejector
- Creator
- Taghavi, R, Raman, G
- Date
- 1996-10
- Publisher
- AMER INST AERONAUT ASTRONAUT
- Title
- PERINATAL PHOTOPERIOD AND LATITUDE AS PREDICTORS OF REACTION TO CHRONOBIOLOGICAL STRESS
- Creator
- Antler, Caroline A.
- Date
- 2013-04-24, 2013-05
- Description
-
The present study explored the possible roles of perinatal photoperiod and latitude as predictors of later reaction to chronobiological stress...
Show moreThe present study explored the possible roles of perinatal photoperiod and latitude as predictors of later reaction to chronobiological stress, specifically the experience of winter in Chicago (41.89°N). Participants consisted of new undergraduate and graduate students at a technological university in Chicago, Illinois (N = 64 - 76). The sample was 62% male, ranged in age from 18 to 38 years (M = 22.5, SD = 4.3), and was born mainly in North America and East/South Asia. The vegetative and cognitive/affective subscales of the Seasonal Assessment Form (SAF; Young et al., 2012) were completed by participants between February 7 and March 7, 2011. Results indicated that both perinatal photoperiod and latitude have a significant effect on vegetative but not cognitive symptom severity. A curvilinear relationship between perinatal photoperiod and winter vegetative symptom severity was displayed with optimal adjustment (minimum vegetative symptoms) occurring near LD 12:12. Attention should be paid to the stronger effect of latitude at birth over perinatal photoperiod on symptom severity. Implications, limitations, and future directions for research are discussed.
M.S. in Psychology, May 2013
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- Title
- Jet Thrust Vectoring Using a Miniature Fluidic Oscillator
- Creator
- Raman, G., Packiarajan, S., Papadopoulos, G.
- Date
- 2005-03
- Publisher
- Royal Aeronautical Soc
- Description
-
This paper presents a new approach to vectoring jet thrust using a miniature fluidic actuator that provided spatially distributed mass...
Show moreThis paper presents a new approach to vectoring jet thrust using a miniature fluidic actuator that provided spatially distributed mass addition. The fluidic actuators used had no moving parts and produced oscillatory flow with a square wave form at frequencies up to 1(.)6kHz. A subsonic jet with an exit diameter of 3(.)81cm was controlled using single and dual fluidic actuators, each with an equivalent circular diameter of 1(.)06mm. The fluidic nozzle was operated at pressures between 20(.)68 and 165(.)47kPa. The objectives of the present work included documentation of the actuation characteristics of fluidic devices, assessment of the effectiveness of fluidic devices for jet thrust vectoring, and evaluation of mass flow requirements for vectoring under various conditions. Measurements were made in the flow field using a pitot probe for the vectored and unvectored cases. Some acoustic measurements were made using microphones in the near-field and for selected cases particle image velocimetry (PIV) measurements were made. Thrust vectoring was obtained in low speed jets by momentum effects with fluidic device mass flow rates of only 2 x 10(-4) kg/sec (0-6% of main jet mass flow per fluidic oscillator). Although a single fluidic device produced vectoring of the primary jet, the dual fluidic device configuration (with two fluidic devices on either side of the jet exit) produced mass flux enhancement of 28% with no vectoring. Our results indicate that fluidic actuators have the potential for use in thrust vectoring, flow mixing and industrial flow deflection applications.
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- Title
- NEW TOOLS FOR JET ANALYSIS IN HIGH ENERGY COLLISIONS
- Creator
- Duffty, Daniel
- Date
- 2015, 2015-05
- Description
-
Our understanding of the fundamental interactions of particles has come far in the last century, and is still pushing forward. As we build...
Show moreOur understanding of the fundamental interactions of particles has come far in the last century, and is still pushing forward. As we build ever more powerful machines to probe higher and higher energies, we will need to develop new tools to not only understand the new physics objects we are trying to detect, but even to understand the environment that we are searching in. We examine methods of identifying both boosted objects and low energy jets which will be shrouded in a sea of noise from other pasts of the detector. We display the power of boosted-b tagging in a simulated W' search. We also examine the effetc of pile up on low energy jet reconstructions. For this purpose we develop a new priority-based jet algorithm, "p-jets", to cluster the energy that belongs together, but ignore the rest.
Ph.D in Physics, May 2015
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- Title
- Chicago Casino: GrainElevatorReuse_CasinoBoard
- Creator
- Sholar, Scott
- Date
- 4/13/2011, 2011-05
- Description
-
Transforming abandoned grain elevators while redefining the normal Casino typology. Understanding the capabilities of abandoned grain...
Show moreTransforming abandoned grain elevators while redefining the normal Casino typology. Understanding the capabilities of abandoned grain elevators and how they can be reused to create a successful design.
Sponsorship: Felsen, Martin
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- Title
- INFLUENCE OF FOUR BACILLUS SP. STRAINS ON GROWTH AND DESULFURIZATION ABILITY OF MYCOBACTERIUM STRAIN U
- Creator
- Tian, Fangzhou
- Date
- 2016, 2016-05
- Description
-
Desulfurization is an important step in crude oil processing and is commonly achieved through a chemical process known as hydrodesulfurization...
Show moreDesulfurization is an important step in crude oil processing and is commonly achieved through a chemical process known as hydrodesulfurization (HDS). Because this process is expensive and produces H2S as a by-product, the alternative of biodesulfurization (BDS) has been investigated for many years. The most potentially useful biodesulfurization process is the 4S pathway, which is found in a number of bacterial species, including Mycobacterium Strain U, which was isolated in our lab. To reach the requirement of BDS for use in an actual industrial-scale process, U has to survive at temperatures approaching 60 OC. In work in our lab, natural selection methods have been introduced for improving the U strain. During this natural selection, four contaminant strains, identified by 16S rDNA sequencing as Bacillus sp., were isolated from extraordinary U cultures which have BDS activity at 54 OC. Meanwhile the BDS activity of U on its own was found to have an upper temperature limitation of 53 OC. Additional experiments proved that all four Bacillus strains interact with U and improve its BDS ability.
M.S. in Biology, May 2016
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- Title
- SIMULATIONS OF CENTERLINE DEFECT CLOSURE IN OPEN DIE FORGING
- Creator
- Gangatirkar, Suhasini
- Date
- 2014, 2014-12
- Description
-
Open die forging is a technique widely used to achieve desired shape and sound mechanical properties. Due to large sizes, the ingots often...
Show moreOpen die forging is a technique widely used to achieve desired shape and sound mechanical properties. Due to large sizes, the ingots often have internal defects such as porosity, shrinkage cavities which damage the overall quality of the final product and affect the mechanical properties of the material. The voids developed during cooling of the ingot have to be treated in the initial forming operation known as cogging which depends on parameters such as die width ratio, die overlap, feed ratio, die shape etc. In this work, finite element method has been used to identify different aspects affecting centerline defect closure, material properties, effect of friction coefficient, relationship between effective strain and the grain size. FORGE 2011 and FORGE NxT 1.0 by Transvalor Corp were used to create numerical models. The material used in this case is H13. Material data and compression test samples were obtained from experiments in a Gleeble 3500. Physical experiments carried out on the Gleeble 3500 were used to determine the coefficient of friction for samples treated at different temperature, strain and strain rates. The effect of these parameters on coefficient of friction was studied in later part of the study. The formulae from the literature used to calculate the coefficient of friction was validated by using simulation models of the compression test samples. These samples were also used to study fraction recrystallized for a particular sample to study the relationship between effective strain and microstructure. Comparisons between validation experiments and simulations showed that there was good agreement between the two and established the effective strain criterion for void closure. From the conclusions obtained from validation experiments, optimal pass schedule was developed to ensure closure of internal voids and uniform distribution of effective strain along centerline for sound quality of the workpiece by changing die overlap percentage every two passes.
M.S. in Material Science Engineering, December 2014
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- Title
- Statistical Monitoring of Complex Chemical Processes Using Agent-Based Systems
- Creator
- Perk, Sinem, Teymour, Fouad, Cinar, Ali
- Date
- 2010-06-02
- Publisher
- AMER CHEMICAL SOC
- Description
-
It is highly desirable to have a statistical process monitoring (SPM) system that detects the abnormalities in process operations quickly with...
Show moreIt is highly desirable to have a statistical process monitoring (SPM) system that detects the abnormalities in process operations quickly with as few missed and false alarms as possible while the process operates under various operating conditions An agent-based combined monitoring and fault detection framework is proposed in this study. In this framework, different SPM techniques compete with and complement each other to enhance detection speed and accuracy. SPM techniques from literature such as principal component analysis (PCA), multiblock PCA (MBPCA), and dynamic PCA (DPCA) techniques are implemented in this agent-based process supervision system An agent performance assessment and agent management layer provides dynamic adaptation of the supervision system and improves the performance of SPM The statistical information coming from each of the statistical techniques is summarized through a consensus mechanism The performance of the agent-based consensus mechanism using different consensus criteria is tested for system disturbances of various magnitudes The effectiveness of the proposed agent-based framework with different consensus criteria is evaluated based on fault detection times and missed alarm rates and the adaptation of the supervision system is illustrated
Endnote format citation for DOI:10.1021/ie901368j
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- Title
- Eleven Words That Sound Like "Orange"
- Creator
- Monica, Samelson
- Date
- 2012, 2012-04
- Title
- Eco-Life (URBAN REDEVELOPMENT following CATASTROPHE in nanjing, china)
- Creator
- Wu, Yingqiu
- Date
- 2011-05-04, 2011-05
- Description
-
My project is an urban redevelopment following catastrophe. A catastrophic explosion in 2010 left a portion of Nanjing city destroyed. The...
Show moreMy project is an urban redevelopment following catastrophe. A catastrophic explosion in 2010 left a portion of Nanjing city destroyed. The project proposes a new urban plan to rebuild the neighborhood and restore the community. A powerful explosion at an abandoned plastics factory in Qixia district of Nanjing city has left several people dead and dozens injured. Buildings and vehicles within 100m of the factory destroyed, 3000 citizen got the key of the street and buildings suffered varying degrees of damage in the area 8 miles in circumference. The blast was caused by a leak from a gas pipeline inside the factory, the blast happened after workers dismantling the plant damaged a propylene pipeline. The leaked gas was then ignited when a car engine was started at the scene. There were a community college and several kindergartens in this area, fortunately, it was summer break at that time, no students hurt reported. It is a unique opportunity to develop a plan in an urban context when the prior years of development have been wiped away. The purpose of the project is giving condos return to 3000 people who lost their houses in the explosion and planing mix-used buildings of the community for next 20 years. At present, many old nerghbourhoods in China are being replaced by new ones. In the most cases, the existing urban patternes are erased and a town is built with out any links to what had previouly existed there. My ptoposal is reusing most of the existing tree line streets, river and bridges. The key of this proposal is sustainability, first idea is using existing river to develop a nice wetland park and the second idea is farming gradens.
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- Title
- Integration of multivariate SPM and FDD by parity space technique for a food pasteurization process
- Creator
- Kosebalaban, F., Cinar, A.
- Date
- 2001-03-15
- Publisher
- PERGAMON-ELSEVIER SCIENCE LTD
- Description
-
Multivariate statistical process monitoring (MSPM), contribution plots, and parity space fault diagnosis (FD) techniques are used to detect...
Show moreMultivariate statistical process monitoring (MSPM), contribution plots, and parity space fault diagnosis (FD) techniques are used to detect abnormal operation of dynamic processes and diagnose sensor and actuator faults. The methods are illustrated by monitoring the critical control points (CCP) and diagnosing causes of abnormal operation of a pilot pasteurization plant. An empirical model of the process is developed by using subspace state space system identification methods and normal process data. The process data collected under the influence of different magnitude and duration of faults in sensors and actuators are used to validate the MSPM and FD techniques. T-2 and squared prediction error (SPEN) charts are used as MSPM charts. A parity space technique for dynamic stochastic systems and dynamic trends in contribution plots of T-2 and SPEN statistics are used for FD. The detection and FD by these techniques show significant improvements over univariate methods.
Endnote format citation
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- Title
- Graduate Student Dwelling: HEJanicaFinalBoard
- Creator
- Janica, H
- Date
- 5/4/2011, 2011-05
- Description
-
The project will seek to create an environment for that fosters living, community, and learning for graduate students at Illinois Institute of...
Show moreThe project will seek to create an environment for that fosters living, community, and learning for graduate students at Illinois Institute of Technology.
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- Title
- Laboratory Notebook 46
- Creator
- Didsatha-amnarj Yanam, Cindy Stewart
- Date
- 2010-03-03T16:37:45Z
- Title
- ANALYSIS AND PROTOTYPING OF ENERGY HARVESTING SYSTEM BASED ON DIELECTRIC ELECTRO ACTIVE POLYMER
- Creator
- He, Peiwen
- Date
- 2012-04-26, 2012-05
- Description
-
Energy harvesting is a new emerging technology which is used to gather am- bient energy from all surroundings. Dielectric Electro Active...
Show moreEnergy harvesting is a new emerging technology which is used to gather am- bient energy from all surroundings. Dielectric Electro Active Polymer (DEAP) is a new material for energy harvesting based on mechanical-to-electric energy conversion. By using MATLAB simulation, a new system design based on DEAP is proposed to harvest energy. In the proposed system, the energy harvesting and the feedback cir- cuit loops can keep the system working without an external source. The simulation results show that the proposed system can harvest energy, and the bias voltage can be supplied by the system itself. Hence, no external source is needed. For circuit level design, based on two different vibration input patterns in terms of mechanical vibration frequency and displacement, two topologies of system forward paths which include DEAP generator, voltage regulation circuit and DC-DC buck converter are designed. For the low frequency high displacement vibration input pattern, a low frequency forward path is developed by using Zener diode regulator. For the high frequency low displacement input pattern, a high frequency forward path is designed by using Butterworth low pass filter. PSPICE simulation results prove that both of the proposed circuits work properly to generate steady DC voltage for energy harvesting. Finally, a prototyping circuit including a low pass filter and a battery charging module is implemented in experiment to verify the feasibility of partial system func- tion. The results show that the prototyping circuit for the proposed energy harvesting system by using DEAP can work well.
M.S. in Electrical Engineering, May 2012
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- Title
- Improved isolation of the p-p underlying event based on minimum-bias trigger-associated hadron correlations, Proceedings of the XLIII International Symposium on Multiparticle Dynamics
- Creator
- Trainor, Thomas, Prindle, Duncan J.
- Date
- 2013-09-15, 2013-09-15
- Publisher
- IIT Press
- Description
-
Some aspects of hadron production in p-p collisions remain unresolved, including the low-hadron-momentum structure of high-parton-energy...
Show moreSome aspects of hadron production in p-p collisions remain unresolved, including the low-hadron-momentum structure of high-parton-energy dijets, separation of triggered dijets from the underlying event (UE), the systematics of multiple parton interactions and possible systematic underestimation of dijet contributions to high-energy nuclear collisions. In this study we apply a minimum-bias trigger-associated (TA) correlation analysis to p-p collisions. We extract a hard component from TA correlations that can be compared with measured jet fragment systematics derived from e+-e− collisions. The kinematic limits on jet fragment production may be determined. The same method may be extended to A-A collisions where the role of minimum-bias jets in spectra and correlations is strongly contested.
Sponsorship: IIT College of Science, High Energy Physics Division of Argonne National Laboratory
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- Title
- A 2-GHZ FREQUENCY MULTIPLIER BASED ON DIGITAL DELAY LOCK LOOP IN 65 NM CMOS
- Creator
- Zhang, Kaiqiang
- Date
- 2017, 2017-05
- Description
-
Generally phase lock loops (PLLs) are utilized in the implementation of the conventional clock generators and frequency multipliers. However...
Show moreGenerally phase lock loops (PLLs) are utilized in the implementation of the conventional clock generators and frequency multipliers. However there are some issues happened during designing PLLs. First of all, PLLs has a stability issue due to its higherorder systems. And this issue will cause the change of the loop bandwidth when PVT is different. Secondly, in PLLs, the output of the VCO will be fed back to the loop, which causes a peak phase error unexpectedly larger than the desired phase variation since jitter is accumulating over the oscillation cycles. These issues will make the design of a PLLbased frequency multiplier more complicated and challenging. In order to solve these issues, this thesis presents a 2-GHz frequency multiplier based on digital delay lock loop. In this design when the DLL is locked the digital DLL operated in the open-loop mode will reduce the jitter and power consumption due to dithering in the lock condition. In this design a compensation structure is proposed to keep track of any potential phase error caused by environmental variations. The reference input frequency is 500M Hz. This frequency multiplier is designed and fabricated in a 65nm CMOS. The thesis also provides theory and simulation results on frequency multiplier for readers.
M.S. in Electrical Engineering, May 2017
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- Title
- Library ReDefinition
- Creator
- Avery, Brian
- Date
- 2011, 2011-05
- Description
-
The Alcuin Library was designed in the 1960's by Marcel Breuer when the purpose of a library was to provide storage of, and access to,...
Show moreThe Alcuin Library was designed in the 1960's by Marcel Breuer when the purpose of a library was to provide storage of, and access to, information. This project is an addition and renovation of the existing academic library into a campus center concentrated on learning information.
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- Title
- PIEZO-BARKHAUSEN PULSE SIGNAL ANALYSES (BPSA) AND DETERMINATION OF THE FATIGUE LIFE OF AISI-1018 STEEL NEAR THE ENDURANCE LIMIT
- Creator
- Nunez-moreno, Federico Alejandro
- Date
- 2014, 2014-05
- Description
-
A series of fatigue tests were performed on two different types of steels named Steel A (annealed and decarbed AISI-1018 steel), and Steel B ...
Show moreA series of fatigue tests were performed on two different types of steels named Steel A (annealed and decarbed AISI-1018 steel), and Steel B (annealed and polished AISI-1018 steel), carried out to separation or to a maximum of 10,000,000 cycles (which was taken to be equivalent to infinite life). Strain levels ranging from 0.0014 in/in (0.0014mm/mm) down to 0.0008in/in (0.0008mm/mm) were used to execute all experimental load tests at a stress ratio R=-1 (complete reversal). An MTS machine was used for these trials. At the same time, magnetic fields and piezo-Barkhausen pulses were recorded by means of a flux gate magnetometer and a copper coil connected to a series of signal filters and amplifiers. Results were used to construct the classical S-N Whöler curve for both steels, as well as in exhibiting the behavior of the magnetic parameters (magnetic excursions, dominant frequencies of the magnetic signals) coupled to the fatigue lives of the samples tested. To describe such couplings, a set of correlations were introduced among the monitored variables as functions of testing time and applied strain. Also, a fractography analysis of the crack patterns using a scanning electron microscope was performed to represent statistically the geometry of “dimples” and fatigue striations from the inception of the crack, until the formation of a shear lip at the final stages of the crack. It was found that the magnitude of the mean amplitude of the piezo-Barkhausen pulses at early stages of the test is correlated to a mid-level energy of cracking, and thus explains the geometry of fatigue striations near the initiation of the crack at higher strain levels, compared to the geometry of the fatigue striations at lower strain levels. x xvi A joint analysis of the amplitudes of the magnetic excursions recorded in time, and the dominant frequencies of the magnetic signals were found to be discriminators of the elastic and plastic behavior of both types of steel. Furthermore the observed magnetic parameter variations determined in a clear way the endurance limit for each type of steel; these values also are in agreement with the strain level for which fatigue lives were greater than 10,000,000 cycles. Based on these results a “bell analogy” for interpreting the fatigue behavior is introduced. Bridge engineering applications and further research is also discussed.
PH.D in Civil Engineering, May 2014
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- Title
- Children's Center for Learning and Joy
- Creator
- Rao, Sijun
- Date
- 5/13/2011, 2011-05
- Description
-
This project provide children with the learning chance they can not get in regular schools. The environment help them develop multiple...
Show moreThis project provide children with the learning chance they can not get in regular schools. The environment help them develop multiple intelligences.
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- Title
- CYBER-PHYSICAL SYSTEM FOR A WATER RECLAMATION PLANT: BALANCING AERATION, ENERGY, AND WATER QUALITY TO MAINTAIN PROCESS RESILIENCE
- Creator
- Zhu, Junjie
- Date
- 2015, 2015-07
- Description
-
Aeration accounts for a large fraction of energy consumption in conventional water reclamation plants (WRPs). Although process operations at...
Show moreAeration accounts for a large fraction of energy consumption in conventional water reclamation plants (WRPs). Although process operations at older WRPs can satisfy effluent permit requirements, they typically operate with excess aeration. More effective process controls at older WRPs can be challenging as operators work to balance higher energy costs and more stringent effluent limitations while managing fluctuating loads. Therefore, understandings of process resilience or ability to quickly return to original operation conditions at a WRP are important. A state-of-art WRP should maintain process resilience to deal with different kinds of perturbations even after optimization of energy demands. This work was to evaluate the applicability and feasibility of cyber-physical system (CPS) for improving operation at Metropolitan Water Reclamation District of Greater Chicago (MWRDGC) Calumet WRP. In this work, a process model was developed and used to better understand the conditions of current Calumet WRP, with additional valuable information from two dissolved oxygen field measurements. Meanwhile, a classification system was developed to reveal the pattern of historical influent scenario based on cluster analysis and cross-tabulation analysis. Based on the results from the classification, typical process control options were investigated. To ensure the feasibility of information acquisition, the reliability and flexibility of soft sensors were assessed to typical influent conditions. Finally, the process resilience was investigated to better balance influent perturbations, energy demands, and effluent quality for long-term operations. These investigations and evaluations show that although the energy demands change as the influent conditions and process controls, in general, aeration savings could be up to 50% from the level of current consumption; with a more xix complex process controls, the saving could be up to 70% in relatively steady-state conditions and at least 40% in relatively challenging transient conditions. The soft sensors can provide reliable and flexible performance on target predictions. The plant can still maintain at a similar level of process resilience after 50% aeration saving, even during long-term perturbations. Overall, this work shows that it is well feasible to provide more cost-effective operations at the Calumet WRP, and meanwhile influent perturbations, effluent quality, and process resilience are well in balance. Keywords: Energy, aeration, effluent quality, perturbation, resilience, water reclamation plant.
Ph.D. in Environmental Engineering, July 2015
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