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- Title
- PHASE EQUILIBRIA AND THERMODYNAMIC MEASUREMENTS OF SOME HEUSLER COMPOUNDS
- Creator
- Chen, Song
- Date
- 2012-08-14, 2012-07
- Description
-
Heusler alloys are compounds based on the original Heusler phase Cu2MnAl which are ternary intermetallics with a particular chemical...
Show moreHeusler alloys are compounds based on the original Heusler phase Cu2MnAl which are ternary intermetallics with a particular chemical stoichiometric formula X2YZ and face-centered cubic structure. Heusler alloys are of interest because of a range of physical phenomena which may occur in them that can be applied in mechanical or electronic devices, including shape memory property and disorder/order phenomenon. In this work, a high temperature drop calorimeters and Setaram calorimeters were used to obtain the enthalpy of formation and heat capacity of compounds in the Mn-based Heusler compounds (X2MnZ). Lattice parameters of these compounds were determined with XRD, and phase equilibria in these alloy system were studied in this work. Phase transformations were studied with DSC and dilatometry. The work is aimed at populating databases for computational thermodynamics, developing an understanding of alloying and clarifying phase equilibria.
M.S. in Material Science and Engineering, July 2012
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- Title
- Thermostatic temperature control for gas engine jacket water
- Creator
- Gross, Morton G, Steiner, Albert J.
- Date
- 2009, 1921
- Publisher
- Armour Institute of Technology
- Description
-
http://www.archive.org/details/thermostatictemp00gros
Thesis (B.S.)--Armour Institute of Technology; Bibliography: leaves 3-4
- Title
- The yield of acetic acid as influenced by temperature in wood distillation
- Creator
- Marx, Walter L.
- Date
- 2009, 1913
- Publisher
- Armour Institute of Technology
- Description
-
http://www.archive.org/details/yieldofaceticaci00marx
Thesis (B.S.)--Armour Institute of Technology; Bibliography: leaf 22
- Title
- SAFETY TRAINING IN CONSTRUCTION
- Creator
- Demirkesen, Sevilay
- Date
- 2011-11-29, 2011-12
- Description
-
The construction industry is one of the most hazardous industries. Therefore, the ways to reduce the number of risks have been a concern for...
Show moreThe construction industry is one of the most hazardous industries. Therefore, the ways to reduce the number of risks have been a concern for construction companies. Safety training is considered as one of the most efficient ways of improving safety record. Therefore, this study aimed to describe the best safety training methods and the most efficient organization in safety training. The study also aimed to show how to take best safety measures to protect construction workers. In this thesis study, a questionnaire was conducted in order to investigate the achievement of safety learning, challenges in a safety training program and the methods of improving safety record. Thus, the questionnaire was e-mailed to 400 contractors in US. The data collected also indicated the importance of safety training in companies’ success in the industry. Additionally, this study presents recommendations on how companies could improve their safety record.
M.S. in Civil Engineering, December 2011
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- Title
- IN VITRO ASSAYS FOR ASSESSING THE IMPACT OF PROCESSING ON THE ALLERGENIC POTENTIAL OF MILK ALLERGENS
- Creator
- Zhao, Yuhui
- Date
- 2014, 2014-07
- Description
-
A better understanding of how processing may affect the allergenicity of proteins will allow a more accurate allergen risk assessment and...
Show moreA better understanding of how processing may affect the allergenicity of proteins will allow a more accurate allergen risk assessment and achieve a greater success in food allergy management. To determine whether food processing can affect the allergenic potential of proteins, immunochemical methods are commonly used, however, these methods are not able to determine changes in the proteins’ ability to elicit allergic reactions. Although food challenge studies are the gold standard for determining the allergenicity of proteins, such studies are seldom performed due to ethical reasons and the difficulty in recruiting a sufficient number of study participants. In recent years, a number of mediator release assays have been developed to measure the allergenic potential of food proteins in vitro. How these cell-based assays can be used to assess the impact of thermal or other processing conditions on the allergenic potential of proteins remains to be determined. This study evaluated the use of sensitized rat basophilic leukemia (RBL) cells for assessing the impact of boiling on the allergenic potential of milk allergens by measuring changes in the proteins’ ability to induce cell degranulation and the release of β-hexosaminidase. RBL-2H3 cells sensitized with rat IgEs that were specifically raised against NIST non-fat milk standard reference material, β-lactoglobulin (BLG), α-lactalbumin (ALA) and α-casein (αCAS) were challenged with various concentrations of each allergen in its native and processed (boiled in PBS for 10 min) forms. Cell degranulation caused by the allergen was monitored by measuring the release of β-hexosaminidase. All allergens (NIST milk, BLG, ALA, and αCAS) were able to induce the release of β-hexosaminidase, up to 43.1%. A decrease in % release of β-hexosaminidase was observed when cells were challenged with a decreasing concenration xi of the ALA and milk allergens. Boiling of nonfat milk, ALA, BLG and αCAS caused an increase in the % release of β-hexosaminidase from sensitized cells across antigen concentrations from 10-6 mg/mL to 1 mg/mL. In conclusion, this study demonstrated that the in vitro mediator release assay method may serve as a useful model to evaluate the impact of thermal processing on the allergenic potential of milk allergens.
M.S. in Food Safety and Technology, July 2014
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- Title
- FINFET BASED STANDARD CELL LIBRARY CHARACTERIZATION
- Creator
- Yuan, Yu
- Date
- 2015, 2015-07
- Description
-
In this work, four standard cell libraries based on FinFET technology have been characterized and implemented. The first library uses the BSIM...
Show moreIn this work, four standard cell libraries based on FinFET technology have been characterized and implemented. The first library uses the BSIM-CMG and PTM-MG models, which represents the common multi-gate devices. Two libraries are based on the BSIM-IMG model, operating in short-gate (corresponding to low-Vt) mode and lowpower (corresponding to high-Vt) mode separately. Synthesis and simulation of BSIMCMG based library is presented and compared to the conventional 45nm CMOS library, FreePDK45. The results show acceptable accuracy of the library based on BSIM-CMG model. For the libraries based on BSIM-IMG model, Short-Gate (SG) mode, Low-Power (LP) mode and the mixed-mode (combining both SG and LP modes) have been analyzed. The results proved that the low-power independent multi-gate FinFET can be used for leakage power reduction, just like the bulk CMOS high-Vt devices. At the end of this work, another library based on CCS model was characterized and verified, which show far better accuracy in terms of both timing and power modeling.
M.S. in Electrical Engineering, July 2015
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- Title
- PREPARATION FOR IMPLANTATION OF AN INTRACORTICAL VISUAL PROSTTIESIS IN A HUMAN: WORKING TOWARDS SATURATION
- Creator
- Troyk, Melissa J
- Date
- 2017, 2017-07
- Description
-
The research focused on restoring visual perception via a vision prosthetic is progressing at a rapidly advancing rate. Previous research on...
Show moreThe research focused on restoring visual perception via a vision prosthetic is progressing at a rapidly advancing rate. Previous research on the experiences and perspectives of past, current, and potential vision prosthesis users has demonstrated that the decision to obtain a vision prosthetic is driven by a variety of unique factors and variables that merge with one another during the process of deciding to participate in clinical vision prosthesis research (Lane, Huyck, Troyk, & Schug, 2012; Lane, Nitsch, Huyck, Troyk, & Schug, 2014; Lane, Nitsch, & Troyk, 2015). The purpose of the current study was twofold: 1) to determine if our understanding of the experiences and perspectives of potential vision prosthesis users was nearing saturation, and 2) to understand the perspectives of potential vision prosthesis users who are veterans. Data were analyzed in accordance with qualitative analysis procedures. Results identified several new themes and subthemes that were determined to be important to our understanding of potential users’ perspectives of an intracortical vision prosthesis device. A preliminary framework is proposed for understanding how the identified themes and subthemes merge during the process of deciding to participate in an experimental vision prosthesis human clinical trial. The results demonstrated that while progress has been made, there is still more to learn about blind individuals’ perspectives of vision prostheses and how they would decide to participate in vision prosthesis research.
M.S. in Psychology, July 2017
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- Title
- PROPOSITION AND EVALUATION OF A NEW DAMPER, CALLED ROTATIONAL CYLINDRICAL FRICTION DAMPER (RCFD)
- Creator
- Divani, Abbass
- Date
- 2013, 2013-12
- Description
-
The objective of this study is to propose and evaluate an innovative frictional damper for structural systems, called Rotational Cylindrical...
Show moreThe objective of this study is to propose and evaluate an innovative frictional damper for structural systems, called Rotational Cylindrical Friction Damper (RCFD), which does not bear limitation of previously proposed systems and yet maintains their advantages. Different kinds of energy dissipaters have been studied and used in structural systems in recent years. They perform more effectively compared to structures without any energy dissipater. Each of previously employed devices has its advantages and limitations. In this report, applicability of previous energy dissipaters will be investigated; then the proposed damper, RCFD, will be introduced, and the performance of RCFD will be evaluated under lateral load using ABAQUS software. RCFD consists of a shaft, a cylinder and proper assembly of braces so that the bracing members make the cylinder and shaft move in opposite circular directions under defined load. The assemblage of braces depends on type of bracing system that is employed. When load in bracing member exceeds the buckling load of the member, it overcomes the friction between the shaft and inner surface of the cylinder and while providing the ductility demand of the structure, it absorbs the energy of the seismic load, and it will work like a safety valve to protect main structural members from inelastic deformation. In spite of other types of frictional dampers, RCFD does not use and reduces the construction cost of high strength bolts. There is no limitation for the size and fitness of the bracing members more than that is for conventional design of braced frames. When we prove the performance of RCFD, some of the requirements of conventional design such as requirement of section F2 of Seismic Provisions for Structural Steel Buildings, AISC 341-10, will be eliminated. The pressure needed for developing friction is provided by heating the shaft and placing it into the cylinder with slightly smaller xiii diameter. It is simple to design and construct and does not have the limitation of other kinds of frictional damper systems. It can also be installed with little or no modification on any kind of Braced Frames or to retrofit Moment Frames. In this study, RCFD will be installed and evaluated on an Inverted V Concentrically Braced Frame, although installation of the RCFD on X Braced frame will be illustrated.
M.S. in Civil Engineering, December 2013
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- Title
- Functionalized Polyoxovanadates: Synthesis, Characterization and Properties
- Creator
- Zheng, Yujuan
- Date
- 2012-04-30, 2011-12
- Description
-
The compound [NaVIV6O6{(OCH2CH2)2NCH2CH2OH}6]Cl.H20, designated C0 in this report, an Anderson type structure, contains a single nitrogen atom...
Show moreThe compound [NaVIV6O6{(OCH2CH2)2NCH2CH2OH}6]Cl.H20, designated C0 in this report, an Anderson type structure, contains a single nitrogen atom in place of a single oxygen atom in each of the six vanadium-oxygen octahedra. Attached to each nitrogen are two alkoxide arms (-O-C-C-) which terminate on separate oxygen atoms of the octahedra. A third ethoxy group (-CH2-CH2-OH) dangles freely from each nitrogen atom. The functionalized cationic core [NaVIV6O6{(OCH2CH2)2NCH2CH2OH}6]+ is generated in situ and is cationic with a charge of +1. Chloride is the counteranion. Each vanadium addenda atom is the +4 oxidation state, and the six unpaired electrons result in interesting magnetic properties. C0 is obtained by reaction of a vanadium oxide source triethanolamine. The purpose of the research described here was to adapt the synthetic protocol associated with triethanolamine to other similar ligands. Ligand choice was motivated by the broader goal of this research group to form (extended) hybrid electronic and magnetic materials by chemically bonding POM cores to chemically interesting ligands, such as dyes or other POM cores. In this regard, the original triethanolamine derivative has a number of shortcomings; chief among them is the inaccessibility of the alcoholic functional group chemistry---due to its low pH---that otherwise might have been used to form linkages through the dangling alkoxy arms. Additionally, linkages containing paraffinic carbon (-C-C-), which is not a good conduit of electronic interaction, are chemically undesirable where the synthetic goal is hybrid structures with interesting electronic and magnetic properties. The results associated with the three ligands, diethanolamine, N,N'-Bis(2-hydroxyethyl)ethylenediamine, and N,N-Bis(2-hydroxyethy) ethylenediamine, are described herein. Diethanolamine was chosen because---based on a structural comparison to triethanolamine---it was expected to produce a structure having a hydrogen atom in place of the dangling ethoxy arms, which was indeed the result. We considered this structure highly desirable becasue of the potential lability of the hydrogen atom (-N-H), which would allow us to functionalist the core directly. The resulting compounds are characterized by single-crystal X-ray diffraction, elemental analysis, mass spectroscopy, thermogravimetric analysis, FT-IR and UV-Vis spectroscopy, maganometric titration, temperature-dependent magnetic susceptibility measurements, and cyclic voltammetry. The results of the cyclicvoltammetric investigation are consistent with the labile hydrogen atom (-N-H).
M.S. in Chemistry, December 2011
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- Title
- MULTIPLE-INPUT MULTIPLE-OUTPUT NONLINEAR CONTROL OF SELECTIVE CATALYTIC REDUCTION SYSTEMS
- Creator
- Dong, Siwei
- Date
- 2015, 2015-05
- Description
-
Selective catalytic reduction (SCR) is one of the most promising solutions to meet the future nitrogen oxides (NOx) emissions regulations for...
Show moreSelective catalytic reduction (SCR) is one of the most promising solutions to meet the future nitrogen oxides (NOx) emissions regulations for heavy-duty diesel vehicles. However, such vehicles often operate in highly transient operations in which mobile selective catalytic reduction systems encounter significant efficiency challenges, especially when the engine is under a low load. A detailed simulation model of the SCR system was developed in the Gamma Technologies simulation suite and a baseline model of feedback control on SCR was constructed. Experiment data for the exhaust gas composition and conditions from a Cummins ISB engine was used to provide the input parameters for the SCR model. The results reveal that in the low-load conditions, the efficiency of NOx reduction in the SCR system is very low, and the level NOx concentration exiting the vehicle could be over 5 times than the limitation set by the US Environmental Protection Agency (EPA). However, these issues are encountered in part due to the fact that current SCR controls focus solely on the aftertreatment components and treat the incoming engine output conditions as system disturbances. To address the low NOx conversion problems encountered in low load conditions, a new integrated engine and aftertreatment control model was designed. This integrated approach improves the SCR system efficiency by using available feedback and modulating the upstream air/fuel ratio to provide more favorable SCR inlet conditions. From experiment data analysis, the engine’s air/fuel ratio is shown to have a critical impact on exhaust gas temperature and exhaust oxygen fraction, which highly affect the SCR reactions. In order to integrate the engine and aftertreatment system, a model of the SCR dynamics was created and validated and a simple model of the relationship between the engine’s air/fuel ratio and resulting exhaust temperature and composition is leveraged. The new model-based control strategy is proven to be effective to improve SCR system performance at low-load operations. With a small value shift in air/fuel ratio, the efficiency of low-load SCR system can increase from 40% to 85% at low load operating conditions.
M.S. in Mechanical and Aerospace Engineering, May 2015
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- Title
- 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
- Some commutation phenomena of direct current machinery
- Creator
- Clark, F. C.
- Date
- 2009, 1905
- Publisher
- Armour Institute of Technology
- Description
-
http://www.archive.org/details/somecommutationp00clar
Thesis (B.S.)--Armour Institute of Technology
- Title
- 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
- Some features of a modern overhead distributing system
- Creator
- Redman, A. R.
- Date
- 2009, 1916
- Publisher
- Armour Institute of Technology
- Description
-
http://www.archive.org/details/somefeaturesofmo00redm
Thesis (B.S.)--Armour Institute of Technology
- Title
- Washington Park Center for Improvisational Music: Kellen White_FINAL 34x44 BOARD_02
- Creator
- White, Kellen
- Date
- 2010-07-30
- Title
- 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
- STRUCTURAL SEISMIC PERFORMANCE EVALUATION WITH CONSIDERATION OF ECONOMIC VULNERABILITY
- Creator
- Romero, Daniela Zuloaga
- Date
- 2014, 2014-05
- Description
-
Performance evaluation of structures has until now been based on evaluation of maximum displacements, interstory drifts, deformation patterns,...
Show morePerformance evaluation of structures has until now been based on evaluation of maximum displacements, interstory drifts, deformation patterns, ductility and other similar parameters; a relative economic loss estimation as a performance measure for the structure is the next step that follows, and is what has been investigated in this work. For this study a steel mid-rise structure was designed according to code provisions using modal spectral analysis, after which it was subjected to an Incremental Dynamic Analysis (IDA) procedure to evaluate the capacity curve of the building. The capacity analysis was then used to determine damage states and compute fragility curves. Finally, economic relative loss values were assigned to represent each designated damage state, for which the mean damage ratio was computed (in terms of economic loss relative to total replacement cost) as a function of spectral displacement.
M.S. in Civil Engineering, May 2014
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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