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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
- DEGRADATION RATE MODEL TO ESTIMATE SOIL CARBON SEQUESTRATION
- Creator
- Zhai, Wenjuan
- Date
- 2016, 2016-05
- Description
-
Concern over climate change as a consequence of carbon dioxide (CO2) emissions from human activities has resulted in efforts to better...
Show moreConcern over climate change as a consequence of carbon dioxide (CO2) emissions from human activities has resulted in efforts to better understand potential mitigation measures such as carbon sequestration in soils. Processes shaping natural carbon sequestration may be used to remove excess CO2 from combustion and other anthropogenic sources of carbon, and, alleviate concerns over climate change. Land application of biosolids is a process that increases the amount of soil carbon sequestration and may produce carbon credits in accordance with the definition of UN Climate Change Convention. A dynamic degradation rate model (DRM) has been developed based on a mass balance and first order kinetics to describe the soil organic carbon (SOC) decomposition process, which provides insights on carbon sequestration due to microbial biomass, SOC, CO2 emission rates, residence time of sequestered carbon, and biomass to biosolids ratios. A curve fitting approach was used to produce a best fit average degradation rate for biosolids degradation and microbial biomass yield. This study employed a 34-year biosolids application database from the literature to determine the amount of carbon sequestered in 41 strip-mined Illinois fields. The DRM application identifies two SOC phases in soil. Soil organic carbon gain in phase one (first 10 yrs) is primarily due to biosolids C application remaining and accumulation while in phase two, SOC gain is due to biomass or C sequestration. Carbon sequestration changes with time relate to variations in biosolids application amounts (10 and 18 Mg ha-1 yr-1), different degradation rate constants (0.04yr-1 to 0.16yr-1), and biomass yields (35 to 40%). Additionally, comparison between model simulation results and laboratory resultsdetermine the amount of carbon sequestered in 41 strip-mined Illinois fields. The DRM application identifies two SOC phases in soil. Soil organic carbon gain in phase one (first 10 yrs) is primarily due to biosolids C application remaining and accumulation while in phase two, SOC gain is due to biomass or C sequestration. Carbon sequestration changes with time relate to variations in biosolids application amounts (10 and 18 Mg ha-1 yr-1), different degradation rate constants (0.04yr-1 to 0.16yr-1), and biomass yields (35 to 40%). Additionally, comparison between model simulation results and laboratory resultsdetermine the amount of carbon sequestered in 41 strip-mined Illinois fields. The DRM application identifies two SOC phases in soil. Soil organic carbon gain in phase one (first 10 yrs) is primarily due to biosolids C application remaining and accumulation while in phase two, SOC gain is due to biomass or C sequestration. Carbon sequestration changes with time relate to variations in biosolids application amounts (10 and 18 Mg ha-1 yr-1), different degradation rate constants (0.04yr-1 to 0.16yr-1), and biomass yields (35 to 40%). Additionally, comparison between model simulation results and laboratory resultsdetermine the amount of carbon sequestered in 41 strip-mined Illinois fields. The DRM application identifies two SOC phases in soil. Soil organic carbon gain in phase one (first 10 yrs) is primarily due to biosolids C application remaining and accumulation while in phase two, SOC gain is due to biomass or C sequestration. Carbon sequestration changes with time relate to variations in biosolids application amounts (10 and 18 Mg ha-1 yr-1), different degradation rate constants (0.04yr-1 to 0.16yr-1), and biomass yields (35 to 40%). Additionally, comparison between model simulation results and laboratory results provided by a yearlong study indicates that higher temperatures and moisture content and finer soils are related to larger degradation rates. To summarize, this study has the following contributions: (1) developed a degradation rate model which simulates the biosolids degradation process in soil and identifies two SOC phases in soil, and quantifies the biosolids degradation rate constant, biomass yield, and the C sequestered amount for multiple and long term soil application; (2) assessed the effect of changes in the amount of biosolids applied, soil type, and weather conditions on the C degradation rate by comparing model results to laboratory data; and (3) provides an easy quantitative method for predicting C sequestration from biosolids added to soil.
Ph.D. in Environmental Engineering, May 2016
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- Title
- SURFACE CHARACTERIZATION OF NIOBIUM FOR SUPERCONDUCTING RF CAVITIES
- Creator
- Cao, Chaoyue
- Date
- 2014, 2014-07
- Description
-
Surface characterization techniques including point contact tunneling (PCT) spectroscopy and Raman spectroscopy have been employed to study...
Show moreSurface characterization techniques including point contact tunneling (PCT) spectroscopy and Raman spectroscopy have been employed to study the surface of niobium (Nb) superconducting radio frequency (SRF) cavities. PCT spectroscopy provides a direct means of measuring the surface superconductivity, which is closely correlated with the cavity’s performance characterized by the quality factor Q. Cavities with remarkably high Q show near ideal tunneling spectra with sharp coherent peaks and low zero bias conductance, consistent with the Bardeen-Cooper-Schrie↵er (BCS) density of states (DOS), and bulk gap parameter, " = 1.55 -1.6 meV. Cavities with Q-drop often exhibit strong non-uniform heating during RF operations, with high loss regions identified as hot spots. PCT spectra on hot spots reveal suppressed superconductivity, broadened DOS and Kondo tunneling, consistent with magnetic impurities on the surface. Raman spectra on hot spots indicate the presence of various impurities on the surface including amorphous carbon, C-H chain compounds and NbC, providing insights into the formation of hot spots. The origin of the impurities is unclear at present but it is suggested that particular processing steps in SRF cavity fabrication may be responsible.
Ph.D. in Physics, July 2014
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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
- BIG DATA SYSTEM INFRASTRUCTURE AT EXTREME SCALES
- Creator
- Zhao, Dongfang
- Date
- 2015, 2015-07
- Description
-
Rapid advances in digital sensors, networks, storage, and computation along with their availability at low cost is leading to the creation of...
Show moreRapid advances in digital sensors, networks, storage, and computation along with their availability at low cost is leading to the creation of huge collections of data { dubbed as Big Data. This data has the potential for enabling new insights that can change the way business, science, and governments deliver services to their consumers and can impact society as a whole. This has led to the emergence of the Big Data Computing paradigm focusing on sensing, collection, storage, management and analysis of data from variety of sources to enable new value and insights. To realize the full potential of Big Data Computing, we need to address several challenges and develop suitable conceptual and technological solutions for dealing them. Today's and tomorrow's extreme-scale computing systems, such as the world's fastest supercomputers, are generating orders of magnitude more data by a variety of scienti c computing applications from all disciplines. This dissertation addresses several big data challenges at extreme scales. First, we quantitatively studied through simulations the predicted performance of existing systems at future scales (for example, exascale 1018 ops). Simulation results suggested that current systems would likely fail to deliver the needed performance at exascale. Then, we proposed a new system architecture and implemented a prototype that was evaluated on tens of thousands nodes on par with the scale of today's largest supercomputers. Micro benchmarks and real-world applications demonstrated the e ectiveness of the proposed architecture: the prototype achieved up to two orders of magnitude higher data movement rate than existing approaches. Moreover, the system prototype was incorporated with features that were not well supported in conventional systems, such as distributed metadata management, distributed caching, lightweight provenance, transparent compression, acceleration through GPU encoding, and parallel serialization. Towards exploring the proposed architecture at millions of node scales, simulations were conducted and evaluated with a variety of workloads, showing near linear scalability and orders of magnitude better performance than today's state-of-the-art storage systems.
Ph.D. in Computer Science, July 2015
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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
- BIO-COMPOSITE NANOMATERIALS; CHARACTERIZATION, MANIPULATION AND APPLICATION
- Creator
- Kim, Taeyoung
- Date
- 2013, 2013-05
- Description
-
Biomaterials are any matter or material which interacts with biological system which were present on natural or synthetic nonviable materials....
Show moreBiomaterials are any matter or material which interacts with biological system which were present on natural or synthetic nonviable materials. An ideal biomaterial must physically and chemically compatible for biological applications to avoid toxicity and immune reaction. Collagen is a widely abundant, robust biopolymer that is found in the extracellular matrix (ECM) of many tissues. In terms of its structure and organization, collagen is a bio-nano material. The use of collagen in stem cell differentiation is particularly enticing since it is now evident that the extracellular matrix (ECM) proteins can regulate the cell’s fate and growth by their molecular and physical properties. In this thesis research, we have characterized the physical and structural properties of collagen and its composite materials. We found collagen interacts with NaCl and other nano-materials, such as carbon nanotube (CNT) and TiO2 nanotube, resulting in the modification of collagen structure and increase of its stiffness. In particular, CNT has changed collagen structure at both the molecular level and the higher organizational level. The effects of the matrices on cell growth and development were studied. It was found that collagen/CNT matrix specify and accelerate the stem cell differentiation toward neural cells. Since neurons form the foundation of biological circuit, manipulation of neurons in growth has the potential to form desired biological circuit. We also examined collagen in vaginal wall connective tissues, and found that alteration of collagen properties in clinical tissues is correlated to the onset of pelvic organ prolapse.
PH.D in Chemistry, May 2013
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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
- PROBING THE PAN-GENOME OF LISTERIA MONOCYTOGENES
- Creator
- Deng, Xiangyu
- Date
- 2011-04-26, 2011-05
- Description
-
Bacterial pathogens often show significant intra-species variations in ecological fitness, host preference and pathogenic potential to cause...
Show moreBacterial pathogens often show significant intra-species variations in ecological fitness, host preference and pathogenic potential to cause infectious disease. The species of Listeria monocytogenes, a facultative intracellular pathogen and the causative agent of human listeriosis, consists of at least three distinct genetic lineages. Two of these lineages predominantly cause human sporadic and epidemic infections, whereas the third lineage has never been implicated in human disease outbreaks despite its overall conservation of many known virulence factors. The genomes of 26 L. monocytogenes strains representing the three lineages are compared based on both in silico comparative genomic analysis and high-density, pan-genomic DNA microarray hybridizations. We uncover 86 genes and 8 small regulatory RNAs that likely make L. monocytogenes lineages differ in carbohydrate utilization and stress resistance during their residence in natural habitats and passage through the host gastrointestinal tract. We also identify 2,330 to 2,456 core genes that define this species along with an open pan-genome pool that contains more than 4,052 genes. Phylogenomic reconstructions based on 3,560 homologous groups allowed robust estimation of phylogenetic relatedness among L. monocytogenes strains. The pan-genome approach enables accurate co-analysis of DNA sequence and hybridization array data for both core gene estimation and phylogenomic reconstruction. Application of our method to the pan-genome of L. monocytogenes sheds new insights into the intra-species genomic diversification, niche expansion and evolution of this important foodborne pathogen.
Ph.D. in Biology, May 2011
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- 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
- 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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