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- Title
- LINEAR AND NONLINEAR BEHAVIOR OF TRANSIENT LIFT RESPONSE TO PULSE-ACTUATION
- Creator
- An, Xuanhong
- Date
- 2014, 2014-07
- Description
-
The transient lift coe cient for a NACA0009 airfoil with pulsed jet actuation type of active ow control at stall conditions is investigated....
Show moreThe transient lift coe cient for a NACA0009 airfoil with pulsed jet actuation type of active ow control at stall conditions is investigated. The experimental mea- surements show the lift coe cient dependence to a single-pulse with di erent pulse widths and amplitudes. Based on the single-pulse with optimal parameters, multi- pulse and continuous pulse actuation cases are studied, which indicate that the pulse interval is the major factor of the active ow control system capability. Linear and nonlinear model are used to predict the lift coe cient variation for di erent input signals to the actuators. A combined nonlinear model is introduced to predict lift coe cient change due to arbitrary unsteady pitching motion with active ow control.
M.S. in Mechanical and Aerospace Engineering, July 2014
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- Title
- OPTIMIZATION OF POWER TRENCH MOSFETS FOR HIGH EFFICIENCY SYNCHRONOUS BUCK CONVERTERS
- Creator
- Wang, Wendi
- Date
- 2016, 2016-05
- Description
-
Synchronous buck converter might be one of the most widely used and fabricated circuitry in the world for its favorable trade-off on many...
Show moreSynchronous buck converter might be one of the most widely used and fabricated circuitry in the world for its favorable trade-off on many subjects. However, the ever higher operation frequency has lead to increasing power loss in power switches and imposed new challenge to MOSFET engineering. One promising alternative for the traditionally used trench MOSFET is the shield gate MOSFET. Shield gate MOSFET has superior conduction performance as well as fast switching transient response due to its Reduced Surface Electric Field (RESURF) effect. In recent years, characterization of power MOSFET has developed along with MOSFET technology itself. New Figure of Merits (FOMs) have come into people's sight as they serve as better standards to fully describe MOSFET's overall performance. Being the same case for many other device structures, this new characterizing system also puts advanced requirements to shield gate MOSFET. And one of the most crucial problems is the rather large output capacitance this structure is having. To improve the property of shield gate MOSFET and meet the requirements of new standards, several ways of structure refinement have been proposed in this work. Both shield gate MOSFET and conventional MOSFET rated at 40V have been designed and simulated in the second chapter. The outcome shows that shield gate MOSFET has superior performance in almost every respect except for its large output charge. Then new structure for COSS reduction has been introduced in the following section, with decrement of about 50% in QQS-1 being achieved. Finally, another issue that has been tackled with is the shoot through of synchronous buck converter. Equivalent circuit model for shoot through analysis is built in this section to study the effect of each parasitic element. And a p type pillar added structure has been verified as an effective way to suppress shoot through gate bounce.
M.S. in Electrical Engineering, May 2016
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- Title
- Washington Park Center for Improvisational Music: Kellen White_FINAL 34x44 BOARD_02
- Creator
- White, Kellen
- Date
- 2010-07-30
- Title
- Sustainable New City - Johor, Malaysia
- Creator
- Meah, Nasser Meah Bin Mahmud
- Date
- 2011-12-06, 2011-12
- Description
-
The purpose of this thesis is to develop an effective design approach necessary in building a new city. The challenge is to assemble a...
Show moreThe purpose of this thesis is to develop an effective design approach necessary in building a new city. The challenge is to assemble a background observations and research that will provide an understanding of the concepts required for developing new sustainable cities. It is hopeful that the ideas and design process can also be a framework to be applied on other undeveloped land that has the potential for new cities particularly in Malaysia. The main idea is to develop a thorough understanding of how the built environment plays an important role in shaping a community as well as identifying the technology involved. It specifically addresses the central issues involved with the art of place making, which determines the success of any particular urbanity. Environment then becomes the most important factor responsible for the physical, mental, and psychological development of an urban society.
M.S. in Architecture, December 2011
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- Title
- ISOGEOMETRIC ANALYSIS VIA TRIANGULATION
- Creator
- Jaxon, Noah
- Date
- 2013-05-15, 2013-05
- Description
-
We present a method for isogeometric analysis on a triangulation of a domain bounded by NURBS curves. In this method, both the geometry and...
Show moreWe present a method for isogeometric analysis on a triangulation of a domain bounded by NURBS curves. In this method, both the geometry and the physical eld are represented by bivariate splines in Bernstein B ezier form over the triangulation. We describe a set of procedures to construct a parametric domain and its triangulation from a given physical domain, construct Cr-smooth basis functions over the domain, and establish a rational Triangular B ezier Spline (rTBS) -based geometric mapping that Cr smoothly maps the parametric domain onto the physical domain and exactly recovers NURBS boundaries. As a result, this approach can achieve automated meshing of objects with complex topologies and allows highly localized re nement. Isogeometric analysis of problems from linear elasticity and advectiondi usion analysis are demonstrated.
M.S. in in Mechanical Engineering, May 2013
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- Title
- COORDINATE-EXCHANGE ALGORITHM CONSTRUCTION OF UNIFORM SPACE FILLING DESIGN
- Creator
- Han, Shipeng
- Date
- 2014, 2014-05
- Description
-
Many scientific phenomena are now investigated by complex computer models. A computer experiment is a sequence of runs with various inputs....
Show moreMany scientific phenomena are now investigated by complex computer models. A computer experiment is a sequence of runs with various inputs. The uniform experimental design seeks its design points to be uniformly scattered on the experimental domain and is one kind of a space-filling design that can be used for computer experiments and OK for industrial experiments. The coordinate-exchange method we use is one-dimensional constrained optimization, searching for the optimal coordinate to make the points filling the space uniformly. This method saves large amounts of calculation compared to the multivariate optimization problems. In this thesis we provide the coordinate-exchange algorithm and demonstrate our methodology with numerical examples. Key words: Coordinate-exchange, Uniform design, Computer experiment, Space-filling design, optimal design.
M.S. in Applied Mathematics, May 2014
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- Title
- Track Elevation
- Creator
- Badger, Le Roy, Walbridge, John T.
- Date
- 2009, 1907
- Publisher
- Armour Institute of Technology
- Description
-
http://www.archive.org/details/trackelevation00badg
Thesis (B.S.)--Armour Institute of Technology; Bibliography: leaves 34-36
- Title
- Zinc nitride, its formation, properties and alloys
- Creator
- Savoye, W. J., Edwards, A. R.
- Date
- 2009, 1921
- Publisher
- Armour Institute of Technology
- Description
-
http://www.archive.org/details/zincnitrideitsfo00savo
Thesis (B.S.)--Armour Institute of Technology; Bibliography: leaves 25-28
- Title
- Informal Learning with Twitter
- Creator
- Wilhelm, Eva C.
- Date
- 2011-04-25, 2011-05
- Description
-
Twitter use has evolved from status updates to a broad range of uses from personal broadcasting to information sharing and conversations. A...
Show moreTwitter use has evolved from status updates to a broad range of uses from personal broadcasting to information sharing and conversations. A study was conducted to determine how Twitter is used for informal learning purposes. It was examined what kind of questions with a learning objective are asked, and under which circumstances these questions are answered. Questions were categorized according to question topic, type, structure and audience. According to the analysis, users most frequently asked for definitions and procedural information about technology, web, software and Twitter use. The questions with the highest answer rate were questions directed at individual users via @replies, and asked about definitions and other factual information.
M.S. in Technical Communication and Informational Design, May 2011
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- Title
- DETECTION OF SUPEROXIDE ANION RADICALS IN ANION EXCHANGE MEMBRANE FUEL CELLS USING IN-SITU FLUORESCENCE SPECTROSCOPY
- Creator
- Zhang, Yunzhu
- Date
- 2016, 2016-07
- Description
-
Anion exchange membrane (AEM) stability is a long-standing challenge that has limited the widespread development and adoption of AEM fuel...
Show moreAnion exchange membrane (AEM) stability is a long-standing challenge that has limited the widespread development and adoption of AEM fuel cells. It is essential to understand the mechanism of AEM degradation during fuel cell operation. There are multiple modes of AEM degradation, broadly classified as chemical, mechanical and thermal degradation. Chemical degradation is among the most destructive modes, and can be further sub-divided into nucleophilic degradation (induced by the hydroxide ion), and oxidative degradation (induced by reactive oxygen species). While the former has been extensively studied, there is minimal work on oxidative AEM degradation. The reactive oxygen chemical species produced during the operation of an AEM fuel cell have hitherto not been detected during operation. Given the high pH, it is postulated that superoxide anion radicals (𝑂2∙−), as opposed to hydroxyl radicals, are primarily involved in the degradation progress. The objective of this study was to confirm the 𝑂2∙− formation during AEM fuel cell operation and to monitor in real-time the rate of 𝑂2∙− generation in an operating fuel cell using in-situ fluorescence spectroscopy. 1,3-diphenlisobenzofuran (DPBF) was chosen as the fluorescence probe, the sensitivity of which towards 𝑂2∙− was evaluated by performing ex-situ experiments in a semi-batch reactor. We demonstrate that the fluorescence intensity of this dye selectively decreased upon exposing 𝑂2∙−. DPBF was then incorporated into an AEM (membrane was solution cast after mixing the dye with the casting solution), which was assembled into a fuel cell. 𝑂2∙− generation in an operating AEM fuel cell was then monitored via in-situ fluorescence spectroscopy using a bifurcated optical probe, when the cell was operated in H2/O2 mode. To confirm the impact of 𝑂2∙− on AEM degradation, independent experiments (without dye) were performed under identical conditions, under both H2/O2 and N2/N2 modes, and the ionic conductivity and ion exchange capacity were monitored to estimate degradation extent. From our in-situ fluorescence studies, we were able to estimate the rate constants and activation energy for oxidative AEM degradation in an operating AEM fuel cell.
M.S. in Chemical Engineering, July 2016
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- Title
- EFFECT OF HIGH PRESSURE PROCESSING ON MIGRATION CHARACTERISTICS IN POLYETHYLENE TEREPHTHALATE FILM
- Creator
- Zhou, Yue
- Date
- 2015, 2015-12
- Description
-
High pressure processing (HPP) is gaining prominence worldwide as an alternative method of food preservation due to its benefits of improved...
Show moreHigh pressure processing (HPP) is gaining prominence worldwide as an alternative method of food preservation due to its benefits of improved quality, freshness and nutrient retention. The use of polymer-based flexible packaging materials has allowed application of HPP to prepackaged food products, without significant loss of physical and mechanical properties. However, there is limited data existing on migration properties in the materials before and/or after HPP. Therefore, it is necessary to evaluate potential migration issues in pre-packed foods during HPP (Song 2014). This research was conducted to determine the migration properties in polyethylene terephthalate (PET) films during and after HPP (121°C and 700MPa) and a comparable thermal processing (TP, 121°C and 0.1MPa), using gas chromatography (GC) coupled with mass spectrometer (MS) technique to quantify four model surrogates in FDA-suggested food simulants (Miglyol). This research will help the U.S Food and Drug Administration (FDA) and food industries to identify whether any safety issue related to chemical migration should be addressed concerning the use of HPP in production of pre-packaged foods.
M.S. in Food Safety and Technology, December 2015
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- Title
- INVOLVEMENT OF MIR-182 IN THE ACTION OF ATORVASTATIN IN PROSTATE CANCER CELLS
- Creator
- Li, Wenping
- Date
- 2013-04-10, 2013-05
- Description
-
Atorvastatin (ATO), a widely used statin for lowering cholesterol was examined for its chemopreventive/therapeutic activities in prostate...
Show moreAtorvastatin (ATO), a widely used statin for lowering cholesterol was examined for its chemopreventive/therapeutic activities in prostate cancer cells. We found that ATO inhibited cell proliferation and induced autophagy in PC3 prostate cancer cells, as marked by significant induction of an autophagy marker LC3-II. Using Taqman RT-PCR technique, we also found that ATO treatment for 24h and 48h consistently up-regulated miR-182 in PC3 cells. However, adding geranylgeraniol (GGOH) to the culture media reversed the effect of ATO in regulating miR-182, suggesting that ATO up-regulates miR-182 through inhibition of geranylgeranyl biosynthesis. Overexpression of miR-182 in PC3 cells significantly decreased cell proliferation by about 36% (MTT assay), while knock-down of miR-182 stimulated cell proliferation by about 43% (MTT assay). In screening for miR-182 target genes, we found that Bcl2 and p21 are potential miR-182 target genes; Bcl2 was significantly down-regulated by ATO at both mRNA and protein levels and miR-182 knock-down up-regulated Bcl2 protein; p21 protein expression was positively correlated with alteration of miR-182 expression levels in PC3 cells. Through screening database of miR-182 target genes from TargetScanHuman 6.2 and PicTar, we found that p21 is not the direct target gene of miR-182, so it could be regulated by miR-182 indirectly. It has recently been established that miR-182 regulation is p53-dependent, since PC3 cells are p53 negative, it is clear that ATO regulates miR-182 in a p53-independent manner. These data demonstrate that miR-182 up-regulation and Bcl2 down-regulation by ATO could be two independent events and both could be involved in ATO mediated cell proliferation and autophagy.
M.S. in Biology, May 2013
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- Title
- Study of automatic electric fire pumps
- Creator
- Ross, L. R., Ballard, L. E., Swearingen, R.e.
- Date
- 2009, 1906
- Publisher
- Armour Institute of Technology
- Description
-
http://www.archive.org/details/studyofautomatic00ross
Thesis (B.S.)--Armour Institute of Technology
- Title
- Using Mitsimlab to Generate Dynamic Traffic for NS2 Simulation of Vanet
- Creator
- Diao, Zhaoshi
- Date
- 2011-04-25, 2011-05
- Description
-
The vehicular ad hoc network (VANET) has attracted a lot of attentions due to their interesting and promising functionalities including...
Show moreThe vehicular ad hoc network (VANET) has attracted a lot of attentions due to their interesting and promising functionalities including vehicular safety, traffic congestion avoidance, and location based services. However, using a real VANET to do these researches costs too much. Simulation of VANET is useful and could solve this problem well. Nevertheless, many simulations of VANET base on simple road networks and relatively simple mobility models. Based on this road networks and mobility models, consequently, the results of simulation of VANET would be impractical and inaccurate. Therefore, MITSIMLAB which is a simulation of transportation system developed by Massachusetts Institution of Technology Intelligent Transportation System Program is introduced. In MITSIMLAB, a real world road network could be generated. Moreover, the mobility models in MITSIMLAB are more practical. However, MITSIMLAB is a simulation of transportation system. It cannot be used to simulate the VANET directly, while NS2 could simulate VANET properly. NS2 is an open sourced and free software, and it is widely used and successfully simulates plenty of situations in the wireless environment. It could well simulate the communication protocols and applications of VANET. But it cannot generate road network and mobility models to simulate a practical traffic by itself. As a result, it is important to incorporate MITSIMLAB by using its practical road network and mobility models with NS2. In the thesis, a method about how to translate the output file of MITSIMLAB into the format of NS2 would be proposed. In addition, a road network based on IIT main campus is generated by using MITSIMLAB. After translating it into the format usable by NS2, a VANET based on the map of IIT main campus and practical mobility models could be simulated.
M.S. in Electrical Engineering, May 2011
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- Title
- IMPROVED DYNAMIC CONTRAST ENHANCED MR IMAGING WITH AN APPLICATION TO PROSTATE CANCER LOCALIZATION
- Creator
- Afshar, Niloufar Totonchi
- Date
- 2011-07, 2011-07
- Description
-
Prostate cancer is one of the most frequently detected cancers and a leading cause of death for men in the United States. Fortunately, chances...
Show moreProstate cancer is one of the most frequently detected cancers and a leading cause of death for men in the United States. Fortunately, chances of successful treatment significantly improve when prostate cancer is diagnosed at an early stage. An accurate and reliable imaging technique that can localize tumors is very valuable for example in guiding needle biopsy, therapy, as well as surgery. Current imaging techniques such as ultrasound provide unsatisfactory result for tumor localization. Therefore, Multispectral Magnetic Resonance Imaging (MRI) emerged as an alternative method of imaging for prostate cancer. An important part of multispectral MRI is Dynamic contrast enhanced MRI (DCE-MRI). Traditionally, a compartmental model is used with DCE-MRI to estimate parametric images. However these images are usually very noisy. Therefore, we propose to use directly the series of DCE-MRI for tumor localization instead of the pharmacokinetic parameters which are derived from DCE MR images through a compartmental model. As a second contribution, we have developed new features in addition to traditional parameters based on different characteristic of tumor and normal pixels. These new features are standard deviation and the energy of the first half of the spectrum divided by the energy of the second half of the spectrum based on an analysis of TACs for tumor and normal pixels. We use quantitative and qualitative evaluation methods to demonstrate that employing DCE-MRI directly as features and our proposed features result in an improvement in terms of tumor localization performance.
M.S. in Electrical Engineering, July 2011
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- Title
- CHANGES OF BACTERIAL SPECIES AND HEME PROTEIN OCCURRENCE IN ACTIVATED SLUDGE COMMUNITIES CULTURED IN THE LABORATORY
- Creator
- Wang, Xiaomeng
- Date
- 2016, 2016-05
- Description
-
An activated sludge sample that had originally been collected from an aeration tank of the Stickney wastewater treatment plant in Chicago, and...
Show moreAn activated sludge sample that had originally been collected from an aeration tank of the Stickney wastewater treatment plant in Chicago, and had previously been cultured at low dissolved oxygen (DO) for 48 weekly passages was used as starting material for continuation of the low DO acclimation. The culture was continued at low dissolved oxygen in synthetic wastewater for 25 additional weekly passages to study what would happen to the activated sludge if the low DO continued. In order to do that, some important data were measured during the culture, including the specific oxygen uptake rates (SOUR) which could reflect the ability of oxygen utilization, 16S rDNA information which could tell the community diversity of sludge, and the dominant species genome data which suggested what really happened to the sludge and some reasons. The results showed that SOUR decreased modestly during the course of low DO adaptation, which was contrary to the results of the previous study. There were significant changes in community structure with respect to bacterial species during the first fifteen additional passages. Species known to produce both flavohemoglobins (FHbs) and truncated hemoglobins (trHbs) were common at all passages tested, although the dominant species were totally different from passage to passage. Specifically, during the course of the experiment, the frequency of cells encoding an FHb decreased substantially, from 84% to 50%, while the percentage of cells encoding a trHb decreased slightly from 84% to 78%. The overall content in the culture of heme b (the heme type found in bacterial hemoglobins) decreased, however, during continuation of the low DO conditions. So it is indicated that the oxygen utilization ability of the activated sludge does not increase all the time.
M.S. in Biology, May 2016
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- Title
- SUSTAINABLE NEW CITY VAN, TURKEY
- Creator
- Dursun, Kevser Pinar
- Date
- 2013, 2013-07
- Description
-
While the negative effects of rapid urbanization is threatening cities and the environment, being more conscientious about the current...
Show moreWhile the negative effects of rapid urbanization is threatening cities and the environment, being more conscientious about the current problems and future expansions of the cities and developing new visions and strategies for new cities is crucial. In this proposal, the aim is to develop a prototype of a sustainable new city in Turkey. Design area is called Carpanak, at the east shore of Lake Van. It is in the north of Van, the biggest city in the Eastern Anatolia district of Turkey. Eastern Anatolia is a mountainous district with a severe climate. The region is less developed than the other regions in every aspect. Severe climate and lack of job opportunities caused outmigration from this region to big cities or onshore regions with more developed industries. A city with sufficient infrastructure, efficient energy solutions, green areas, well-designed transportation, economic viability, and open social structure will help reverse the migration and rescue Eastern Anatolia from being abandoned. It is hoped that the design decisions, ideas, and the research can be applied as an outline to other underdeveloped areas in Turkey.
M.S. in Architecture, July 2013
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- Title
- Incubator for Small Business Manufacturing
- Creator
- Victor, Jimeniz
- Date
- 2010-07-29
- Title
- The thermal conductivity of various forms of tile and their value as fireproofing materials
- Creator
- Anderson, S. W., Chamberlin, J. F.
- Date
- 2009, 1915
- Publisher
- Armour Institute of Technology
- Description
-
http://www.archive.org/details/thermalconductiv00ande
Thesis (B.S.)--Armour Institute of Technology
- Title
- The study of an air washer
- Creator
- Armspach, Otto W., Haines, E. Wilfred
- Date
- 2009, 1917
- Publisher
- Armour Institute of Technology
- Description
-
http://www.archive.org/details/studyofairwasher00arms
Thesis (B.S.)--Armour Institute of Technology