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Title: HEAT PUMPS IN DRINKING WATER UTILITY BUILDINGS
Creator: Colomer Pons, Ana Maria
Date: 2012-07-12, 2012-07
Description: In the United States each person consumes about 70 million BTUs per year in the residential sector, a tendency that is constantly growing...
Show moreIn the United States each person consumes about 70 million BTUs per year in the residential sector, a tendency that is constantly growing because of technology and society growth (EIA, 2011). The United States Department of Energy (USDOE, 1988) reported that heat pumps are energy efficient devices that can provide heating and cooling in residential and industrial buildings and also in households. According to Bernier (2006) heat pumps offer many advantages such as decreased space needs, higher efficiencies, and lower maintenance costs, and that is why they have been implemented in many regions throughout the United States as well as in many European countries. However, their use is many times hindered due to the high initial costs relative to conventional heating air conditioning ventilating systems (HVAC), technologies that are widely known and have been used for many years. The purpose of this thesis is to analyze the performance, economic feasibility, and greenhouse gas emission reduction of implementing heat pump devices in drinking water plants for heating and cooling needs inside the building. The proposed system is similar to groundwater heat pumps (described in an upcoming section) but instead of groundwater the heat pump relies on drinking water that has been treated in the plant and it is ready for its use. Groundwater has one main advantage because it is at a constant temperature year round (NRC, 2005) which gives the heat pump system stability in its behavior. Moreover, it is at a higher temperature than air in winter, and at a lower temperature than air in summer, which makes it an excellent candidate for heat transfer purposes in the refrigeration cycle. The four cases studies described in this work examine medium and high efficiency heat pumps installed in existing plants and new plants. Because drinking water is readily available after its treatment, the cost of drilling and grouting is avoided and this high quality water also avoids most of the problems related to quality of water such as scaling or fouling. This system gives a return of investment that is in all cases lower than six years. emissions are reduced by about 50 per cent because the use of a much more efficient device produces less for each kWh of heating or cooling delivered in the building.
M.S. in Environmental Engineering, July 2012
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Title: PLS, balanced, and canonical variate realization techniques for identifying VARMA models in state space
Creator: Negiz, A., Cinar, A.
Date: 1997-10
Publisher: ELSEVIER SCIENCE BV
Description: This paper demonstrates the application of PLS regression, balanced realization, and canonical variate (CV) state space modeling techniques in...
Show moreThis paper demonstrates the application of PLS regression, balanced realization, and canonical variate (CV) state space modeling techniques in identifying stationary vector autoregressive moving average (VARMA) type of time series models in state space. An example VARMA process model is used to generate data, carry out modeling activities, and compare the three model development techniques. All realization methods provide equivalent state space models. Balanced realization can not handle singularities in the covariance matrix of past observations while all other methods can accommodate such singularities. Balanced realization and classical PLS do not provide minimal state variables that are orthogonal. 'Orthogonal states' PLS and canonical variate state space realization give orthogonal state variables that provide robust parameter estimates from real data, however the PLS method requires an additional singular value decomposition step.
Endnote format citation
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Title: SRAM DESIGN BASED ON CNFET: A DISCUSSION ON CIRCUIT, PARAMETER AND DIAMETER VARIATION
Creator: Yu, Zhiyuan
Date: 2011-05-05, 2011-05
Description: This thesis describes the effort in designing SRAMs based on Carbon Nanotube Field Effect Transistor (CNFET), and covers several aspects...
Show moreThis thesis describes the effort in designing SRAMs based on Carbon Nanotube Field Effect Transistor (CNFET), and covers several aspects including circuit structure, parameters, layout and the detection of diameter variation. It aims at providing a primitive reference on the topic of employing CNFETs in realistic SRAM design. In this thesis, we propose a guideline for choosing appropriate transistor ratios with respect to differently selected diameters in a conventional 6-T SRAM. Constraints of transistor ratios are established, followed by the optimization of the ratios regarding Static Noise Margin (SNM) and Read Noise Margin (RNM) of the cell. With the optimal parameters, the CNFET cell can achieve 41.41% and 1.26% improvement over traditional CMOS in SNM and RNM, respectively. Then we propose a column-based monitoring circuit which is capable of detecting variation in the diameter of tubes. It is grounded on a novel layout of the 6-T SRAM based on CNFET, which assigns all cells in a column of the SRAM array to the same group of Carbon Nanotubes (CNTs). This monitor outputs a digital signal indicating the impact of diameter variation on delay of the circuit, and enables further mitigation of the variation. Alternatively, a new 6-T SRAM cell structure is proposed for optimizing the performance of the cell at very-low or sub-threshold supply voltages. Compared with a traditional 6-T cell, simulation results show that the reading and writing delay have been improved by more than 80% and 75% at 0.4V supply voltage, respectively. It achieves PDP reduction of 70% and 91% for reading and writing operations.
M.S. in Electrical Engineering, May 2011
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Title: Eco-Life (URBAN REDEVELOPMENT following CATASTROPHE in nanjing, china): Yingqiu Wu_Master project_May 2011++
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: Planning for Human Implantation of a Cortical Visual Prosthesis (sequence unknown), IPRO 334 - Deliverables: IPRO 334 Project Plan F09
Creator: Bern, David, Chen, Shanyl, Deroo, Mary, Gorski, David, Kelly, Thomas, Leasenby, Alex, Li, Zhi, Pyrkh, Hanna, Subhani, Maham, Taneja, Aanchal
Date: 2009-12
Description: The Intracortical Visual Prosthesis is based upon that concept that by implanting a large number of subminiature electrodes within the human...
Show moreThe Intracortical Visual Prosthesis is based upon that concept that by implanting a large number of subminiature electrodes within the human visual cortex, coordinated temporal-spatial image information can be artificially communicated to the human visual cortex in the form of electrical currents, acting as a sensory substitute for normal vision.
Sponsorship: IIT Laboratory of Neural Prosthetic Research
Deliverables for IPRO 334: Planning for Human Implantation of a Cortical Visual Prosthesis for the fall 2009 semester
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Title: Bike Chicago
Creator: Moore, Matt
Date: 2010-07-29

Title: The treatment of stock yard's sewage by the activated sludge process
Creator: Newman, Joseph Julius
Date: 2009, 1917
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/treatmentofstock00newm
Thesis (B.S.)--Armour Institute of Technology; Includes folded leaves in back pocket

Title: COMPARISON BETWEEN TWO CHITIN-PURIFIED PRO-DEATH PROTEINS IN MITOCHONDRIA TARGETING ANALYSIS
Creator: Yeap, Xin Yi
Date: 2011-04-19, 2011-05
Description: Bax protein belongs to the Bcl-2 family. It is pro-apoptotic and the most common form is Bax α. When a cell receives death stimuli, Bax...
Show moreBax protein belongs to the Bcl-2 family. It is pro-apoptotic and the most common form is Bax α. When a cell receives death stimuli, Bax protein will oligomerize and target to mitochondria. Another isoform of Bax called Bax 2, which has lost exon 2 and has a frame shift mutation, is verified to be more potent in inducing apoptosis than Bax α. Here, we would like to understand more about Bax 2 mitochondria targeting ability compared to the more common Bax α form. We first set up a cell-free system which contained purified Bax protein and purified mitochondria. The mitochondrial binding protein was identified using fractionation and Western blot with Bax isoformspecific antibodies. Integration of Bax protein into the mitochondrial membrane was determined using the alkaline stripping method. The results suggest that the majority of Bax α targeted and integrated into the mitochondria membrane, while the majority of Bax 2 did not target to mitochondria in the cell-free system. This may suggest that Bax 2 might need additional help from certain cytosol components such as co-factors to target to mitochondria or that Bax 2 induces cell death through a mechanism other than mitochondrial targeting.
M.S. in Biology, May 2011
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Title: DEVELOPMENT OF NANOPARTICLE APPLICATIONS IN CELL IMAGING, BIOASSAY AND REACTIVE OXYGEN SPECIES DETECTION BASED ON SURFACE-ENHANCED RAMAN SPECTROSCOPY
Creator: Yiming, Huang
Date: 2011-08, 2011-07
Description: After mid-1970, the exploration of surface-enhanced Raman scattering (SERS) has been studied by many research groups. Compared to traditional...
Show moreAfter mid-1970, the exploration of surface-enhanced Raman scattering (SERS) has been studied by many research groups. Compared to traditional Raman spectroscopy, enormous cross section of molecules can be obtained in SERS by placing the molecules within the electromagnetic field present in metal surfaces. This enhancement is due to resonance between the optical field and surface plasmon of the metal substrate. Nanoshells which are composed of a silica core and a thin gold shell can greatly enhance Raman scattering without the need to pre-aggregate the particles, due to their tunable optical property. In our study, we synthesized nanoshells as our SERS substrates for Raman tags. The stability of nanoshells coated with three different self-assembled monolayers containing poly(ethylene glycol) (PEG) molecules has been studied. Probes with Raman active PEG molecules have been delivered and imaged in macrophage cells and MCF7 cells, based on SERS technique. The benefits of this imaging technique we developed here are: 1) it is faster; 2) it requires less preparation; 3) it can provide the information of nanoshells in a semi-quantitative way in vitro. We also developed a rapid and easy-to-execute half-sandwich bioassay for the detection of low volumes (< 2 μL) of antigens on nitrocellulose membrane, based on SERS. Multiple antibodies with MW from 18.2 kDa to 170 kDa were bioconjugated to polymers and grafted to nanoshell surface to detect antigens on the membrane. SERS-based biosensors were tagged with Raman active PEGs for recognition and quantification. Here, the bioassay showed great sensitivity to very low concentration x viii of antigens and multiplexed testing have been successfully conducted on different antigens simultaneously. Moreover, SERS-based novel reactive oxygen species (ROS) sensors were designed by establishing mixed-monolayer consisting of poly(ethylene) glycol thiol (PEGSH) and either 4-nitrobenzenethiol (4-NBT) or 4-mercaptophenol (4-MP) on the surface of nanoshells. By analyzing the changes in the molecular Raman spectrum, we were able to track the production of hydroxyl radicals in low concentrations (~ 10 μM). The sensors have been delivered into the cells and did not show significant oxidative stress to the cells. Therefore, these designed sensors are very promising for tracking ROS produced by cells when they are under oxidative stress.
Ph.D. in Chemistry, July 2011
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Title: MODE SPECTRA OF NATURAL DISTURBANCES IN A CIRCULAR JET AND THE EFFECT OF ACOUSTIC FORCING
Creator: Raman, G, Rice, Ej, Reshotko, E
Date: 1994-10
Publisher: SPRINGER VERLAG
Description: A modal spectrum technique was used to study coherent instability modes (both axisymmetric and azimuthal) triggered by naturally occurring...
Show moreA modal spectrum technique was used to study coherent instability modes (both axisymmetric and azimuthal) triggered by naturally occurring disturbances in a circular jet. This technique was applied to a high Reynolds number (400,000) jet for both untripped (transitional) and tripped (turbulent) nozzle exit boundary layers, with both cases having a core turbulence level of 0.15%. The region up to the end of the potential core was dominated by the axisymmetric mode, with the azimuthal modes dominating further downstream. The growth of the azimuthal modes was observed closer to the nozzle exit for the jet with a transitional boundary layer. Whether for locally parallel flow or slowly diverging flow, even at low levels of acoustic forcing, the inviscid linear theory is seen to be inadequate for predicting the amplitude of the forced mode. In contrast, the energy integral approach reasonably predicts the evolution of the forced mode.
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Title: THE MOLECULAR MECHANISM OF BAXΔ2-MEDIATED CELL DEATH AND ITS TISSUE DISTRIBUTION IN COLON CANCER
Creator: Zhang, Honghong
Date: 2014, 2014-07
Description: Bax is a pro-death tumor suppressor in the Bcl-2 family, and is frequently mutated in microsatellite instable tumors, especially Hereditary...
Show moreBax is a pro-death tumor suppressor in the Bcl-2 family, and is frequently mutated in microsatellite instable tumors, especially Hereditary Non-Polyposis Colorectal Cancer (HNPCC). The loss of apoptotic Bax contributes to tumor development and chemoresistance. We recently uncovered that the combination of a Bax microsatellite mutation with a specific alternative splicing generated a unique Bax isoform (BaxΔ2) in Bax-negative cells. Similar to the prototype Baxα, BaxΔ2 is a potent pro-apoptotic molecule. However, the pro-apoptotic mechanism, therapeutic implication, and tumor tissue distribution of BaxΔ2 protein remain elusive. In this thesis research, we isolated and analyzed isogenic sub-cell lines that represent different Bax microsatellite statuses from colorectal cancer cells. We found that the colon cancer cells harboring Bax microsatellite G7/G7 alleles produced low levels of endogenous BaxΔ2 transcripts and proteins. BaxΔ2-positive cells were selectively sensitive to a subgroup of chemotherapeutics in comparison with BaxΔ2-negative cells. Different from other Bax isoforms, which mostly act through targeting mitochondria, BaxΔ2 recruited caspase-8 into the aggregates for activation, and consequently induced cell death independent of the mitochondrial pathway. Furthermore, the distribution of BaxΔ2 protein was mostly found in well-differentiated epithelial cells in primary colon tumor tissues or in primary squamous buccal cells, which contain Bax G7 mutation. However, not all cells harboring the Bax G7 mutation had a detectable level of BaxΔ2 proteins. These data suggest that, similar to Baxα, BaxΔ2 protein is pro-apoptotic, but not toxic to normal cells; expression of BaxΔ2 protein restores apoptotic program in Bax negative cells via a non-classical signaling pathway. Importantly, BaxΔ2 may provide a selective chemotherapeutic advantage for certain Bax-negative colon tumors.
Ph.D. in Biology, July 2014
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Title: SPAM DETECTION IN SOCIAL NETWORKS: A CASE STUDY OF WEIBO
Creator: Guo, Chang
Date: 2012-07-11, 2012-07
Description: Online Social Network Service (OSNS) lead the fashion on internet nowadays[43]. Hundreds of millions people are using Facebook, Twitter,...
Show moreOnline Social Network Service (OSNS) lead the fashion on internet nowadays[43]. Hundreds of millions people are using Facebook, Twitter, MySpace and other similar OSNS all over the world[18]. In China, people use Sina Weibo, Tencent Weibo, Renren instead of Facebook and Twitter. With those miracle tools, people communicate with others far from them at real time. However, in the wrong hands, those virtual communicating services are vulnerable from being leveraged to spread harmful or unwelcome spam messages to large number of people instantly. Besides illegal advertisements, the even worse spam messages could mislead you to phishing websites, or malware downloading links. Your account may be compromised and be used by spammers to continue spreading the virus to your acquaintance. The fight with spammers has been over decades. Thousands of smart scholars has developed different strategies to auto filter most of the spam messages[10][12][18]. In E-mail system, the earliest platform leveraged by spammers and hackers, it is reported that 98% of the common spam e-mails could be identified[5]. But in OSNS, it is just the beginning of the fight. In this work, I present a further study on the behavior of spammers and spammer accounts in Sina Weibo, the most popular OSNS in China. From the data I collected, I learn the differences pattern between spammers and legitimate users and try to finally identify the spammers. I study a dataset of 220K user profile data and 2.1 million of their most recent posted tweets. My method could finally recognize 84.4% of the spammer account while the overall classification accuracy achieves 89.9%. Because this method does not rely on the content of messages but the structure and pattern of them, I believe this method should work well for other OSNS such as twitter as well.
M.S. in Computer Science, July 2012
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Title: SUPPORT VECTOR MACHINE BASED CLASSIFICATION FOR TRAFFIC SIGNS AND ULTRASONIC FLAW DETECTION
Creator: Virupakshappa, Kushal
Date: 2015, 2015-12
Description: The use of machine learning techniques for the advanced signal and image processing applications is gaining importance due to performance...
Show moreThe use of machine learning techniques for the advanced signal and image processing applications is gaining importance due to performance increases in accuracy and robustness. Support Vector Machine (SVM) is a machine learning method used for classification and regression analysis of complex real-world problems that may be difficult to analyze theoretically. In this dissertation, the use of SVM for the application of ultrasonic flaw detection and traffic sign classification has been investigated and new methods are introduced. For traffic sign detection, Bag of visual Words technique has been implemented on Speeded Up Robust Feature (SURF) descriptors of the traffic signs and later the sturdy classifier SVM is used to categorize the traffic signs to its respective groups. Experimental results demonstrate that the proposed method of implementation can reach an accuracy of 95.2 % . For ultrasonic aw detection, subband decomposition filters are used to generate the necessary feature vectors for the SVM classifier. Experimental results, using A-scan data measurements from a steel block, show that a very high classification accuracy can be achieved. Robust performance of the classifier is due to proper selection of frequency-diverse feature vectors and successful training. SVM has also been used for regression analysis to locate and amplify the aw by suppressing the clutter noise. The results show that the use of SVM is reliable and achievable for both the applications.
M.S. in Electrical Engineering, December 2015
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$Central exclusive production and the Durham diffractive program$

Title: Central exclusive production and the Durham diffractive program, Proceedings of the XLIII International Symposium on Multiparticle Dynamics
Creator: Harland-lang, L. A., Khoze, V. A., Ryskin, M. G.
Date: 2013-09-15, 2013-09-15
Publisher: IIT Press
Description: Recent results in central exclusive production within the Durham model are presented. A wide range of processes are considered, and their...
Show moreRecent results in central exclusive production within the Durham model are presented. A wide range of processes are considered, and their theoretical and phenomenological interest is discussed.
Sponsorship: IIT College of Science, High Energy Physics Division of Argonne National Laboratory
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Title: DEVELOPMENT OF COMPUTER-AIDED DIAGNOSIS METHODS IN MAMMOGRAPHY
Creator: Wang, Juan
Date: 2015, 2015-12
Description: Computer-aided diagnosis (CAD) is developed as a diagnostic aid to provide a “second opinion” in diagnosis of breast cancer in early stage....
Show moreComputer-aided diagnosis (CAD) is developed as a diagnostic aid to provide a “second opinion” in diagnosis of breast cancer in early stage. Clustered microcalcifications (MCs) can be an important early sign of breast cancer. The goal of this work is to develop automatic CAD methods in mammography for breast cancer. Its contribution consists of both development of machine learning algorithms and study of related issues in detection and diagnosis of breast cancer with clustered MCs. First, a bi-thresholding scheme is proposed for reduction of false-positives (FPs) associated with linear structures in MC detection. An unified classifier with dummy variable modeling is further developed to reduce the FPs caused by both linear structures and MC-like noise patterns. It is demonstrated that both of the proposed algorithms can reduce FPs in MC detection, and thus, improve the detection accuracy significantly. Second, a spatial density modeling approach is investigated to quantify the spatial distribution of the MCs in a cluster when the MC detection is inaccurate. A spatial density function (SDF) is defined such that the extracted features are more robust to the presence of FPs and false-negatives (FNs) in MC detection. The results show that the features extracted from the SDF can achieve better class separation while being robust to the variations in MC detection when compared with those extracted from a traditional region-based method. Third, a retrieval-boosted approach is studied to discriminate between the benign and malignant MC lesions. A retrieval strategy is proposed to boost the classification performance by taking into account the similarity both in image features and in pathology. An adaptive Adaboost classifier, which can be adapted to the retrieved cases at a low computational cost, is applied to demonstrate the benefit of the retrieval strategy. The results show that the retrieval-boosted approach can signifishow that the features extracted from the SDF can achieve better class separation while being robust to the variations in MC detection when compared with those extracted from a traditional region-based method. Third, a retrieval-boosted approach is studied to discriminate between the benign and malignant MC lesions. A retrieval strategy is proposed to boost the classification performance by taking into account the similarity both in image features and in pathology. An adaptive Adaboost classifier, which can be adapted to the retrieved cases at a low computational cost, is applied to demonstrate the benefit of the retrieval strategy. The results show that the retrieval-boosted approach can significantly outperform its baseline classifier and that inclusion of pathology information in the retrieval can further improve the classification accuracy. Fourth, the perceptual similarity of MC lesions by radiologists is studied. The issues investigated include the degree of variability in the similarity ratings, the impact of this variability on agreement between readers in retrieval of similar lesions, and the factors contributing to the readers’ similarity ratings. The results indicate that perceptually similar lesions could be of diagnostic value in diagnosis for clustered MCs. Fifth, the feasibility of modeling the perceptual similarity of MC lesions is investigated. A support vector regression (SVR) is applied to model the perceptual similarity of clustered MCs, and a feature saliency analysis derived from SVR is used to determine the most relevant image features among a large set of candidate features. The results demonstrate that the relevant features are consistent in radiologists’ similarity ratings among different MC lesions, indicating that the perceptual similarity of MC lesions by radiologists can be effectively modeled. Finally, whether retrieval of similar images can effectively assist radiologists in diagnosis of clustered MCs is investigated. A retrieval system for relevant images is designed by considering both perceptually similar image features and the likelihood of malignancy of the lesion under consideration. An observer study is conducted to evaluate the diagnostic value of the proposed retrieval system. The results indicate that the proposed retrieval system has the potential to improve the reader’s ability in diagnosis of breast cancer with clustered MCs.
Ph.D. in Electrical Engineering, December 2015
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Title: Quantitative Tools for Stochastic Dynamical Systems: Invariant Structures and Escape Probabilities
Creator: Kan, Xingye
Date: 2012-07-16, 2012-07
Description: Three types of quantitative structures, stochastic inertial manifolds, random invariant foliations, and escape probabilities, are investigated...
Show moreThree types of quantitative structures, stochastic inertial manifolds, random invariant foliations, and escape probabilities, are investigated to study stochastic dynamical systems. Invariant structures for stochastic dynamical systems are reviewed and detailed techniques for their simulation, approximation and construction are presented with several illustrative examples. First, a numerical approach for the simulation of inertial manifolds of stochastic evolutionary equations with multiplicative noise is presented and illustrated. After splitting the stochastic evolutionary equations into a backward and a forward part, a numerical scheme is devised for solving this backward-forward stochastic system, and an ensemble of graphs representing the inertial manifold is consequently obtained. This numerical approach is tested in two illustrative examples: one is for a stochastic differential equation and the other is for a stochastic partial differential equation. Second, invariant foliations for dynamical systems with small white noisy perturbation are approximated via asymptotic analysis. In other words, random invariant foliations are represented as a perturbation of the corresponding deterministic invariant foliations, with deviation errors estimated. The escape probability is a deterministic concept making methods of partial differential equations theory attainable to stochastic dynamics. Finally, the escape probability p(x) for dynamical systems driven by non-Gaussian L´evy motions, especially symmetric α-stable L´evy motions, is considered and characterized. More precisely, it is represented as the solution of the Balayage-Dirichlet problem of a certain partial differential-integral equation. This issue has been investigated previously for dynamical systems driven by Wiener process. Differences between escape probabilities for dynamical systems driven by Gaussian and non-Gaussian noises are highlighted.
Ph.D. in Applied Mathematics, July 2012
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Title: A study of neutral currents in star connected three-phase alternators and transformers
Creator: Kaiser, Everett Dee, Myers, Frank Edward
Date: 2009, 1911
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/studyofneutralcu00kais
Thesis (B.S.)--Armour Institute of Technology; Includes bibliographical references and index

Title: EVALUATION OF FLIP-FLOP JET NOZZLES FOR USE AS PRACTICAL EXCITATION DEVICES
Creator: Raman, G, Rice, Ej, Cornelius, Dm
Date: 1994-09
Publisher: ASME-AMER SOC MECHANICAL ENG
Description: This paper describes the flowfield characteristics of the flip-flop jet nozzle and the potential for using this nozzle as a practical...
Show moreThis paper describes the flowfield characteristics of the flip-flop jet nozzle and the potential for using this nozzle as a practical excitation device. It appears from the existing body of published information that there is a lack of data on the parameters affecting the operation of such nozzles and on the mechanism of operation of these nozzles. An attempt is made in the present work to study the important parameters affecting the operation and performance of a flip-flop jet nozzle. Measurements were carried out to systematically assess the effect of varying the nozzle pressure ratio (NPR) as well as the length and volume of the feedback tube on the frequency of oscillation of this device. Flow visualization was used to obtain a better understanding of the jet flowfield and of the processes occurring within the feedback tube. The frequency of oscillation of the flip-flop jet depended significantly on the feedback tube length and volume as well as on the nozzle pressure ratio. In contrast, the coherent velocity perturbation levels did not depend on the above-mentioned parameters. The data presented in this paper would be useful for modeling such flip-flop excitation devices that are potentially useful for controlling practical shear flows.
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Title: POWER PROFILING, ANALYSIS, LEARNING, AND MANAGEMENT FOR HIGH-PERFORMANCE COMPUTING
Creator: Wallace, Sean
Date: 2017, 2017-05
Description: As the field of supercomputing continues its relentless push towards greater speeds and higher levels of parallelism the power consumption of...
Show moreAs the field of supercomputing continues its relentless push towards greater speeds and higher levels of parallelism the power consumption of these large scale systems is steadily transitioning from a burden to a serious problem. While the machines are highly scaleable, the buildings, power supplies, etc. are not. Even the most power efficient systems today consume one to two megawatts per peata op/s. Multiplying that by 1,000 to reach the next generation of supercomputer (i.e., exascale) and the power necessary just to turn the machine on is simply impractical. Thus, power has become a primary design constraint for future supercomputing system designs. As such, it has become a matter of paramount importance to understand exactly how current generation systems utilize power and what implications this has on future systems. As the saying goes, you can't manage what you don't measure. This work addresses several large hurdles in fully understanding the power consumption of current systems and making actionable decisions based on this understanding. First, by leveraging environmental data collected from runs of real leadership class applications we analyze power consumption and temperature as it pertains to scale on a production IBM Blue Gene/Q supercomputer. Then, through development of a new power monitoring library, MonEQ, we quantitatively studied how power is consumed in major portions of the system (e.g., CPU, memory, etc.) through profiling of microbenchmarks. Expanding on this, we then studied how scale and network topology affect power consumption for several well-known benchmarks. Wanting to increase the effectiveness of our power monitoring library, we extended it to work with many of the most common classes of hardware available in today's HPC landscape. In doing so, we provided an in-depth analysis of what data is obtainable, what the process of obtaining it is like, and how data from different systems compares. Next, utilizing the knowledge gained from these experiences, we developed a new scheduling approach which utilizing power data can effectively keep a production system's power consumption under a user-specified power cap without modification to the applications running on the system. Finally, we extend this scheduling approach to be applicable to more than just one objective. In doing so, the scheduler can now optimize on multiple criteria instead of simply considering system utilization.
Ph.D. in Computer Science, May 2017
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Title: SEISMIC DESIGN STUDY OF STEEL PLATE SHEAR WALL
Creator: Moshiri, Ali
Date: 2012-04-20, 2012-05
Description: plate shear walls are an innovative lateral load-resisting system capable of effectively and economically bracing a building against both wind...
Show moreplate shear walls are an innovative lateral load-resisting system capable of effectively and economically bracing a building against both wind and earthquake forces. The system consists of infill steel plates connected to boundary beams and columns over the full height of the framed bay. Beam-to-column connections can be rigid or shear connections and the infill plates can be either stiffened or unstiffened, depending on the design philosophy of the infill plates. The view of some structural designers is to use heavy stiffeners to reinforce and increase the buckling capacity of shear walls, whereas, if the walls are left unstiffened and allowed to buckle, their energy absorption will increase significantly due to the post-buckling capacity. Performance of 9-story SPSW with moment resisting beam to column connections was studied under quasi-static loading condition and 10 earthquake records recorded in Los Angeles by developing a nonlinear dynamic explicit finite element models in ABAQUS. All the models were validated with experimental results. Effect of stiffness of boundary elements (VBE and HBE) and plate thickness on general behavior of the structure were also investigated. In design of SPSWs, vertical boundary elements play a major role in increasing the capacity of the system. In high seismic zones there is always a chance of plastic hinge formation in the boundary elements specially columns in any intermediate floor. It is recommended that SPSWs not be used for medium to high rise buildings in high seismic regions until the lack of capacity design requirements for this type of SPSW is rectified.
Ph.D. in Structural Engineering, May 2012
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