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Articles 1 - 30 of 30
Full-Text Articles in Engineering
Application Aware For Byzantine Fault Tolerance, Hua Chai
Application Aware For Byzantine Fault Tolerance, Hua Chai
ETD Archive
Driven by the need for higher reliability of many distributed systems, various replication-based fault tolerance technologies have been widely studied. A prominent technology is Byzantine fault tolerance (BFT). BFT can help achieve high availability and trustworthiness by ensuring replica consistency despite the presence of hardware failures and malicious faults on a small portion of the replicas. However, most state-of-the-art BFT algorithms are designed for generic stateful applications that require the total ordering of all incoming requests and the sequential execution of such requests. In this dissertation research, we recognize that a straightforward application of existing BFT algorithms is often inappropriate …
Potential Optimal Gait Performance Of Mauch S-N-S Prosthetic Knee Configurations As Predicted By Dynamic Modeling, Chih-Hao Chien
Potential Optimal Gait Performance Of Mauch S-N-S Prosthetic Knee Configurations As Predicted By Dynamic Modeling, Chih-Hao Chien
ETD Archive
Patients with prosthetic legs routinely suffer from abnormal gait patterns which can cause health issues and eventually lower the quality of their lives. Despite the half-century advance in the technology of prosthetic knees, from the purely mechanical to microprocessor controlled systems, patient testing suggests that very little progress has been made in the quality of the kinetics and kinematics of amputee gait. Moreover, the cost of microprocessor controlled prosthetic knees may be 10 times more than the purely mechanical knees. While prosthetic knees have become more complex and expensive, it is not proven that the prosthetic knee is a central …
Biogeography-Based Optimization For Combinatorial Problems And Complex Systems, Dawei Du
Biogeography-Based Optimization For Combinatorial Problems And Complex Systems, Dawei Du
ETD Archive
Biogeography-based optimization (BBO) is a heuristic evolutionary algorithm that has shown good performance on many problems. In this dissertation, three problem1s 1 are researched for BBO: convergence speed and optimal solution convergence of BBO,1 1BBO application to combinatorial problems, and BBO application to complex systems. The first problem is to analyze BBO from two perspectives: how the components of BBO affect its convergence speed and the reason that BBO converges to the optimal solution. For the first perspective, which is convergence speed, we analyze the two essential components of BBO -- population construction and information sharing. For the second perspective, …
Oppositional Biogeography-Based Optimization, Mehmet Ergezer
Oppositional Biogeography-Based Optimization, Mehmet Ergezer
ETD Archive
This dissertation outlines a novel variation of biogeography-based optimization (BBO), which is an evolutionary algorithm (EA) developed for global optimization. The new algorithm employs opposition-based learning (OBL) alongside BBO migration to create oppositional BBO (OB BO). Additionally, a new opposition method named quasi-reflection is introduced. Quasireflection is based on opposite numbers theory and we mathematically prove that it has the highest expected probability of being closer to the problem solution among all OBL methods that we explore. Performance of quasi-opposition is validated by mathematical analysis for a single-dimensional problem and by simulations for higher dimensions. Experiments are performed on benchmark …
Development Of Chatter Attenuation Robust Control For An Amb Machine Spindle, Alexander Hans Pesch
Development Of Chatter Attenuation Robust Control For An Amb Machine Spindle, Alexander Hans Pesch
ETD Archive
No abstract provided.
A Probabilistic Based Failure Model For Components Fabricated From Anisotropic Graphite, Chengfeng Xiao
A Probabilistic Based Failure Model For Components Fabricated From Anisotropic Graphite, Chengfeng Xiao
ETD Archive
The nuclear moderator for high temperature nuclear reactors are fabricated from graphite. During reactor operations graphite components are subjected to complex stress states arising from structural loads, thermal gradients, neutron irradiation damage, and seismic events. Graphite is a quasi-brittle material. Two aspects of nuclear gradegraphite, i.e., material anisotropy and different behavior in tension and compression, are explicitly accounted for in this effort. Fracture mechanic methods are useful for metal alloys, but they are problematic for anisotropic materials with a microstructure that makes it difficult to identify a "critical" flaw. In fact cracking in a graphite core component does not necessarily …
Byzantine Fault Tolerance For Distributed Systems, Honglei Zhang
Byzantine Fault Tolerance For Distributed Systems, Honglei Zhang
ETD Archive
The growing reliance on online services imposes a high dependability requirement on the computer systems that provide these services. Byzantine fault tolerance (BFT) is a promising technology to solidify such systems for the much needed high dependability. BFT employs redundant copies of the servers and ensures that a replicated system continues providing correct services despite the attacks on a small portion of the system. In this dissertation research, I developed novel algorithms and mechanisms to control various types of application nondeterminism and to ensure the long-term reliability of BFT systems via a migration-based proactive recovery scheme. I also investigated a …
Mineral Uptake Rates And Yield Coefficients Of The Green Microalgae Scenedesmus Dimorphus, Grace N. Mahfouz
Mineral Uptake Rates And Yield Coefficients Of The Green Microalgae Scenedesmus Dimorphus, Grace N. Mahfouz
ETD Archive
The need for renewable sources of energy has become critical as fossil fuel resources, which include oil, coal, and natural gas, are known to contribute to climate change and will eventually be depleted. Biofuels that originate from the fat of plants, animals, microalgae, and bacteria are an attractive alternative. Microalgae, in particular, are strong candidates for biofuel production since they have a high growth rate and lipid content (up to 50 in some species). The goal of this research was to optimize 3N-BBM+V recipe (Bold Basal Medium with 3-fold Nitrogen and Vitamins) in an effort of reducing the amount of …
Installation And Field Testing Of High Performance Repair Materials For Pavements And Bridge Decks, Andrew Lesak
Installation And Field Testing Of High Performance Repair Materials For Pavements And Bridge Decks, Andrew Lesak
ETD Archive
Pavement patching is a common maintenance activity in the state of Ohio, due to numerous freeze-thaw cycles. The Ohio Transportation (ODOT) has a need for durable, more permanent high performing pavement and bridge deck materials that allow for a faster repair and for user safety. New or proprietary products were chosen, installed, and monitored in order to specify for use in future ODOT construction, based on the field performance of the products. The objective of this study was to document the investigation, installation, and field testing of the previously chosen high performance patching materials. The investigation determined the proper field …
Implementation And Field Testing Of Improved Bridge Parapet Designs, Amy E. Kalabon
Implementation And Field Testing Of Improved Bridge Parapet Designs, Amy E. Kalabon
ETD Archive
Premature cracking of concrete bridge parapets is a potentially complex problem, with a number of possible causes. Identifying the cause of premature cracking, and avoiding this problem in the future has several benefits, including: a potential cost savings for the district, improving the safety of these structures in future construction, and increasing the overall understanding of parapets. The objective of this study was to analyze the reasons for uncontrolled cracking in order to establish an improved parapet design, and provide recommendations to the Ohio Transportation (ODOT) to prevent such cracking in the future. Previous research carried out a forensic investigation …
Selection Of High Performance Repair Materials For Pavements And Bridge Decks, Alice E. Sommerville
Selection Of High Performance Repair Materials For Pavements And Bridge Decks, Alice E. Sommerville
ETD Archive
The Ohio Transportation has identified the need to specify durable, more permanent high performing pavement and bridge deck patching materials. These materials need to allow for expedited pavement and bridge deck wearing surface repair for worker and user safety. Currently, either temporary or generally specified in-kind or like materials are being used to perform pavement patching. Usually, the Department provides generically specified cementitious or cold mix asphalt materials for patching wearing surfaces with varied performance characteristics. Current products used for these repairs are generally those that have been used for many decades for which competition exists. However, new or proprietary …
Design Of Recombinant Tenebrio Molitor Antifreeze Protein For Purification Using Elastin-Like Polypeptide Tag, Joongseok Oh
Design Of Recombinant Tenebrio Molitor Antifreeze Protein For Purification Using Elastin-Like Polypeptide Tag, Joongseok Oh
ETD Archive
Fusion protein technologies can aid to improve solubility of recombinant protein from microorganisms and help recombinant protein purification. Elastin-like polypeptides (ELP) as a fusion tag can be utilized to facilitate the purification of recombinant proteins because ELP can provide its thermally responsive behavior to ELP tagged proteins. An ELP tag can be used as the purification carrier through inverse transition cycling (ITC), which is a simple and non chromatographic separation process. The purification through ITC can reduce cost and can be quickly performed compared to other purification methods. However, we further considered ELP tag removal because it may possibly hinder …
Color Removal From Dye And Sugar Wastewater Using Coagulation And Microfiltration Processes, Saketh Thanneeru
Color Removal From Dye And Sugar Wastewater Using Coagulation And Microfiltration Processes, Saketh Thanneeru
ETD Archive
The water is widely used in process industries, but its use is not always made in a rational way. Due to the growing demand for water by the people and industries, it is necessary to consider the new problem of water supply. Water contamination by organic and inorganic compounds is of great public concern. The textile and sugar industry are the major producers of the wastewater with a varying parameters. Even though there are new technologies for color removal till this date coagulation is seen as the most economical alternative to all technologies present now. In this thesis we study …
Numerical Investigation Of Boiling In A Sealed Tank In Microgravity, Sonya Lynn Hylton
Numerical Investigation Of Boiling In A Sealed Tank In Microgravity, Sonya Lynn Hylton
ETD Archive
NASA's missions in space depend on the storage of cryogenic fluids for fuel and for life support. During long-term storage, heat can leak into the cryogenic fluid tanks. Heat leaks can cause evaporation of the liquid, which pressurizes the tank. However, when the tanks are in a microgravity environment, with reduced natural convection, heat leaks can also create superheated regions in the liquid. This may lead to boiling, resulting in much greater pressure rises than evaporation at the interface between the liquid and vapor phases. Models for predicting the pressure rise are needed to aid in developing methods to control …
Land Use And Transportation Modeling, Gerayeli Alireza
Land Use And Transportation Modeling, Gerayeli Alireza
ETD Archive
Across the United States, the need and value of coordinated land use and transportation planning have become a highly debated topic. There are those who believe that the coordination of land use and transportation is best served in the development of compact communities with alternate modes of travel. This approach is thought to preserve natural resources and result in a reduction in the number and length of vehicle trips. Others believe that such compact developments will lead to highly congested transportation systems. The Federal Highway Administration (FHWA) has acknowledged the need and value of coordinating land use and transportation planning, …
Computation Of Fifteen Thermodynamic Properties Along Arbitrary Paths From Fundamental Equations Of State Correlations, Prashanth Krishnamoorthy
Computation Of Fifteen Thermodynamic Properties Along Arbitrary Paths From Fundamental Equations Of State Correlations, Prashanth Krishnamoorthy
ETD Archive
In this work, a set of fifteen thermodynamic properties for thirty pure compounds has been estimated using fundamental equations of state (FEOS). A computer program was written which allows to input any two of four fundamental thermodynamic properties entropy, pressure, temperature and density to fix a state point and then use the FEOS to generate any other property at that given state. The program further applies the FEOS to trace thermodynamic processes like isochoric, isobaric, isenthalpic, isothermal and isentropic state changes to find the final state of the compound. The program subsequently displays the initial, final and intermediate state points …
Biogeography-Based Optimization Of A Variable Camshaft Timing System, George L. Thomas
Biogeography-Based Optimization Of A Variable Camshaft Timing System, George L. Thomas
ETD Archive
Automotive system optimization problems are difficult to solve with traditional optimization techniques because the optimization problems are complex, and the simulations are computationally expensive. These two characteristics motivate the use of evolutionary algorithms and meta-modeling techniques respectively. In this work, we apply biogeography-based optimization (BBO) to radial basis function (RBF)-based lookup table controls of a variable camshaft timing system for fuel economy optimization. Also, we reduce computational search effort by finding an effective parameterization of the problem, optimizing the parameters of the BBO algorithm for the problem, and estimating the cost of a portion of the candidate solutions in BBO …
Evolutionary Optimization Of Atrial Fibrillation Diagnostic Algorithms, Aref Smiley
Evolutionary Optimization Of Atrial Fibrillation Diagnostic Algorithms, Aref Smiley
ETD Archive
The goal of this research is to introduce an improved method for detecting atrial fibrillation (AF). The foundation of our algorithm is the irregularity of the RR intervals in the electrocardiogram (ECG) signal, and their correlation with AF. Three statistical techniques, including root mean squares of successive differences (RMSSD), turning points ratio (TPR), and Shannon entropy (SE), are used to detect RR interval irregularity. We use the Massachusetts Institution of Technology / Beth Israel Hospital (MIT-BIH) atrial fibrillation databases and their annotations to tune the parameters of the statistical methods by biogeography-based optimization (BBO), which is an evolutionary optimization algorithm. …
Laboratory Measurements Of The Deep Venusian Atmosphere, Timothy J. Palinski
Laboratory Measurements Of The Deep Venusian Atmosphere, Timothy J. Palinski
ETD Archive
NASA Glenn Research Center has designed and built a test chamber that can recreate the hot, dense atmospheric conditions of the deep Venusian atmosphere, where pressures range as high as 92 atmospheres and temperatures as high as 740 K. The majority of this thesis lies in experimentally measuring and quantifying the infrared absorption of CO2 at Venus-like conditions in this laboratory setting. In particular, we describe the challenges and solutions involved in achieving repeatable laboratory test conditions, as well as the iterative process of modifying/optimizing our experimental test setup, including proposed future improvements. We discuss our measured CO2 absorption spectra, …
Tcp Ftat (Fast Transmit Adaptive Transmission): A New End-To-End Congestion Control Algorithm, Mohammed Ahmed Melegy Mohammed Afifi
Tcp Ftat (Fast Transmit Adaptive Transmission): A New End-To-End Congestion Control Algorithm, Mohammed Ahmed Melegy Mohammed Afifi
ETD Archive
Congestion Control in TCP is the algorithm that controls allocation of network resources for a number of competing users sharing a network. The nature of computer networks, which can be described from the TCP protocol perspective as unknown resources for unknown traffic of users, means that the functionality of the congestion control algorithm in TCP requires explicit feedback from the network on which it operates. Unfortunately this is not the way it works with TCP, as one of the fundamental principles of the TCP protocol is to be end-to-end, in order to be able to operate on any network, which …
A Psa Process For An Oxygen Concentrator, Aaron A. Moran
A Psa Process For An Oxygen Concentrator, Aaron A. Moran
ETD Archive
Oxygen is used in a variety of chemical processes and for medical purposes throughout the world. Pressure swing adsorption (PSA) has become a viable alternative to cryogenic distillation for the separation of oxygen from air with the development of advanced adsorbents like zeolites. PSA processes are inherently complex because it is a dynamic process. Efficient operation of a PSA process is necessary in order to utilize the capacity of the adsorbent as much as possible and reduce the power requirements of the process.In this thesis, a novel zeolite adsorbent was utilized in a PSA process for oxygen generation with the …
Human Hair Keratin Protein, Hair Fibers And Hydroxyapatite (Ha) Composite Scaffold For Bone Tissue Regeneration, Samuel Siyum
Human Hair Keratin Protein, Hair Fibers And Hydroxyapatite (Ha) Composite Scaffold For Bone Tissue Regeneration, Samuel Siyum
ETD Archive
The field of tissue engineering aims at promoting the regeneration of tissues or replacement of failing or malfunctioning tissue by means of combining a scaffold material, adequate cells and bioactive molecules. Different materials have been proposed for use as three-dimensional porous scaffolds for bone tissue engineering procedures. Among them, polymers of natural origin are one of the most attractive options mainly due to their similarities with the extracellular matrix (ECM), chemical versatility as well as typically good biological performance. In this study, two biocompatible composite scaffolds were developed from natural polymer by tissue engineering approach and tested in vitro. The …
Validation Of An Accelerometry Based Method Of Human Gait Analysis, Obinna Nwanna
Validation Of An Accelerometry Based Method Of Human Gait Analysis, Obinna Nwanna
ETD Archive
Gait analysis is the quantification of locomotion. Understanding the science behind the way we move is of interest to a wide variety of fields. Medical professionals might use gait analysis to track the rehabilitation progress of a patient. An engineer may want to design wearable robotics to augment a human operator. Use cases even extend into the sport and entertainment industries. Typically, a gait analysis is performed in a highly specialized laboratory containing cumbersome expensive equipment. The process is tedious and requires specially trained operators. Continued development of small and cheap inertial measurement units (IMUs) over an alternative to current …
Benefits Of Nitric Oxide Cues To Matrix Synthesis By Healthy And Aneurysmal Human Smooth Muscle Cells Within 3d Cocultures, Phillip Simmers
Benefits Of Nitric Oxide Cues To Matrix Synthesis By Healthy And Aneurysmal Human Smooth Muscle Cells Within 3d Cocultures, Phillip Simmers
ETD Archive
Vascular diseases such as atherosclerosis and aneurysms are characterized by the over-proliferation and migration of aortic smooth muscle cells (SMCs), and degradation of extracellular matrix (ECM) within the vessel wall, leading to compromise in cell-cell and cell-matrix signaling pathways. Recent tissue engineering approaches to regulate SMC over-proliferation and enhance healthy ECM synthesis showed promise, but resulted in low crosslinking efficiency and matrix deposition yields. In this study, the benefits of exogenous nitric oxide cues, delivered from S-Nitrosoglutathione (GSNO), to cell proliferation and matrix deposition by adult human aortic SMCs (HA-SMCs) within 3D biomimetic cultures have been explored. The first experiment …
Effects Of Environmental Heavy Metals On Neural Stem Cell Survival And Differentiation, Sameera S. Clev Tasneem
Effects Of Environmental Heavy Metals On Neural Stem Cell Survival And Differentiation, Sameera S. Clev Tasneem
ETD Archive
No abstract provided.
Developing Improved Bridge Parapet Designs, Lauren A. Hedges
Developing Improved Bridge Parapet Designs, Lauren A. Hedges
ETD Archive
The Ohio Department of Transportation has identified that premature parapet cracking is a significant problem in Northeast Ohio. Background research related to concrete cracking and parapet cracking was conducted to determine possible causes of the premature cracking that ODOT has discovered. To further look at possible causes of this cracking, current ODOT bridge parapet practices were reviewed. In addition to ODOT practices, ten other state DOTs were surveyed to identify the bridge parapet practices used. These practices include the parapet design characteristics, construction joint spacing and depth, and the class of concrete used for construction. Various differences among all of …
Electrostatically Controlled Enzymatic Reaction, Metabolic Processes And Microbial Generation Of Electric Power, Yang Song
ETD Archive
This thesis shows that electric fields can be used to control electron transport in biological systems and improve the performance of biological devices using an external gating voltage. It has recently been shown that an ultrasensitive detection method based on electric field effect can be used to control the kinetics of enzymatic conversion of glucose. The first part of the thesis is a mechanistic study of the enzyme catalyzed conversion of glucose to gluconolactone using the field effect enzymatic detection (FEED) technique. Use of a voltage controlled enzymatic system decreased electrons tunnel between electrode and active center of glucose oxidase …
Program Verification Of Freertos Using Microsoft Dafny, Matthew J. Matias
Program Verification Of Freertos Using Microsoft Dafny, Matthew J. Matias
ETD Archive
FreeRTOS is a popular real-time and embedded operating system. Real-time software requires code reviews, software tests, and other various quality assurance activities to ensure minimal defects. This free and open-source operating system has claims of robustness and quality [26]. Real-time and embedded software is found commonly in systems directly impacting human life and require a low defect rate. In such critical software, traditional quality assurance may not suce in minimizing software defects. When traditional software quality assurance is not enough for defect removal, software engineering formal methods may help minimize defects. A formal method such as program verication is useful …
Bio-Inspired Optimization Of Ultra-Wideband Patch Antennas Using Graphics Processing Unit Acceleration, Brian Vyhnalek
Bio-Inspired Optimization Of Ultra-Wideband Patch Antennas Using Graphics Processing Unit Acceleration, Brian Vyhnalek
ETD Archive
Ultra-wideband (UWB) wireless systems have recently gained considerable attention as effective communications platforms with the properties of low power and high data rates. Applications of UWB such as wireless USB put size constraints on the antenna, however, which can be very dicult to meet using typical narrow band antenna designs. The aim of this thesis is to show how bio-inspired evolutionary optimization algorithms, in particular genetic algorithm (GA), particle swarm optimization (PSO) and biogeography-based optimization (BBO) can produce novel UWB planar patch antenna designs that meet a size constraint of a 10 mm 10 mm patch. Each potential antenna design …
Development Of Test Methodology For Evaluation Of Fuel Economy In Motorcycle Engines, Alexander Michlberger
Development Of Test Methodology For Evaluation Of Fuel Economy In Motorcycle Engines, Alexander Michlberger
ETD Archive
Rising fuel costs and concerns over fossil fuel emissions have resulted in more stringent fuel economy and emissions standards globally. As a result, motor vehicle manufacturers are constantly pushed to develop more efficient engine and drivetrain systems. Along with advances in hardware, the development of highly fuel efficient engine oils and driveline lubricants can have a significant impact on total system efficiency. Recently motorcycle fuel economy and emissions have come under increased scrutiny. While the passenger vehicle and heavy duty vehicle industries employ a variety of American Society for Testing and Materials (ASTM) standardized tests to measure fuel economy and …