Search Results (1 - 25 of 208 Results)

Sort By  
Sort Dir
 
Results per page  

Calvitti, AlanPhase Locking in Coupled Oscillators as Hybrid Automata
Doctor of Philosophy, Case Western Reserve University, 2004, Systems and Control Engineering
Cruse's model of leg coordination (CCM) was derived to account for gaits and gait transitions in arthropods (analogous to, e.g. walktrotgallop in some quadrupeds). It has also been adapted to control locomotion in a series of hexapod robots. CCM is a systems-level, kinematic model that abstracts key physiological and dynamical properties in favor of tractability. A key feature is that gaits emerge from interaction among pairs of legs as effected by a set of coordination mechanisms acting at discrete points in time. We represent CCM networks as systems of coupled hybrid oscillators. Gaits are quantified by a temporal (discrete) phase vector. System trajectories are polyhedral, hence solvable over finite-time, but the presence of the switching automaton renders infinite horizon properties harder to analyze. Via numerical and symbolic simulations, we have mapped out the synchronization behavior of CCM networks of various topologies parametrically. We have developed a section-map analysis approach that exploits the polyhedral geometry of the hybrid state space. Our approach is constructive. Once switching boundaries are appropriately parameterized, we can extract periodic orbits, their domains of admissibility and stability, as well as expressions for the period of oscillation and relative phase of each cycle, parametrically. Applied to 2-oscillator networks, our approach yields excellent agreement with simulation results. A key emergent concept is that of a virtual periodic orbit (VPO). Distinguished from admissible periodic orbits, VPOs do not correspond to any in the underlying hybrid dynamics. However, when stable and close to being admissible, they are canonical precursors for a class of nonsmooth bifurcations and predictive of long transient behavior. Last, we take into consideration the possibility and difficulties of extending our approach to larger networks and to related oscillator-like hybrid dynamical systems with polyhedral trajectories.

Committee:

Randall Beer (Advisor)

Keywords:

bifurcations in hybrid systems; coupled oscillators; discrete event control; distributed control; entrainment; gaits and gait transitions; geometry of hybrid systems; hybrid dynamics; hybrid systems; phase locking; piecewise linear dynamics

Koprubasi, KeremModeling and Control of a Hybrid-Electric Vehicle for Drivability and Fuel Economy Improvements
Doctor of Philosophy, The Ohio State University, 2008, Mechanical Engineering

The gradual decline of oil reserves and the increasing demandfor energy over the past decades has resulted in automotive manufacturers seeking alternative solutions to reduce the dependency on fossil-based fuels for transportation. A viable technology that enables significant improvements in the overall tank-to-wheel vehicle energy conversion efficiencies is the hybridization of electrical and conventional drive systems.

Sophisticated hybrid powertrain configurations require careful coordination of the actuators and the onboard energy sources for optimum use of the energy saving benefits. The term optimality is often associated with fuel economy, although other measures such as drivability and exhaust emissions are also equally important. This dissertation focuses on the design of hybrid-electric vehicle (HEV) control strategies that aim to minimize fuel consumption while maintaining good vehicle drivability.

In order to facilitate the design of controllers based on mathematical models of the HEV system, a dynamic model that is capable of predicting longitudinal vehicle responses in the low-to-mid frequency region (up to 10 Hz) is developed for a parallel HEV configuration. The model is validated using experimental data from various driving modes including electric only, engine only and hybrid. The high fidelity of the model makes it possible to accurately identify critical drivability issues such as time lags, shunt, shuffle, torque holes and hesitation.

Using the information derived from the vehicle model, an energy management strategy is developed and implemented on a test vehicle. The resulting control strategy has a hybrid structure in the sense that the main mode of operation (the hybrid mode) is occasionally interrupted by event-based rules to enable the use of the engine start-stop function. The changes in the driveline dynamics during this transition further contribute to the hybrid nature of the system.

To address the unique characteristics of the HEV drivetrain and to ensure smooth vehicle operation during mode changes, a special control method is developed. This method is generalized to a broad class of switched systems in which the switching conditions are state dependent or are supervised. The control approach involves partitioning the state-space such that the control law is modified as the state trajectory approaches a switching set and the state is steered to a location within the partition with low transitioning cost. Away from the partitions that contain switching sets, the controller is designed to achieve any suitable control objective. In the case of the HEV control problem, this objective generally involves minimizing fuel consumption.

Finally, the experimental verification of this control method is illustrated using the application that originally motivated the development of this approach: the control of a HEV driveline during the transition from electric only to hybrid mode.

Committee:

Giorgio Rizzoni, PhD (Advisor); Yann Guezennec, PhD (Committee Member); Andrea Serrani, PhD (Committee Member); Steve Yurkovich, PhD (Committee Member)

Subjects:

Mechanical Engineering

Keywords:

Hybrid electric vehicles; hybrid vehicles; automotive control systems; vehicle modeling; model validation; driveline control; control of switched systems; energy management in hybrid vehicles;

Hadley, Tiffany SunshineNot All Reality Is Created Equal: A Rhetorical Hybrid Conspiracy and Diatribe in Michael Moore’s Fahrenheit 9/11
MA, University of Cincinnati, 2006, Arts and Sciences : Communication
The controversial documentaries by Michael Moore have provoked public debate on social and political matters since the end of the 1980s. This study analyzed Michael Moore’s Fahrenheit 9/11 from a dualistic approach. Utilizing media scholar Nichols’ documentary modes of representation, this study identified three emergent modes: expository, participatory, and politically reflexive. This project also examined the extent to which these three modes reflected a particular view toward the rhetorical situation. Often times situations arise that call for a dual response. Jamieson and Campbell’s generic hybrid was also used to assess the extent in which Fahrenheit 9/11 responded to the needs of the situation and the audience. The hybrid blend Moore used was comprised of the conspiracy and diatribe genres. Not only did these two genres fulfill the perceived needs of the audience and situation, but they also worked together in such a way that elements of each genre buttress the weaknesses of the other.

Committee:

Dr. Stephen Depoe (Advisor)

Keywords:

Michael Moore; Documentary; Diatribe; Conspiracy; Hybrid; Generic Hybrid; Rhetorical Hybrid; Modes of Representation; Nichols

Joshi, Ninad MilindStudy of the Effect of Unidirectional Carbon Fiber in Hybrid Glass Fiber / Carbon Fiber Sandwich Box Beams
Master of Science (M.S.), University of Dayton, 2013, Materials Engineering
This study investigated the effect of carbon fiber placed in different amount at different location in a square box beam. In total eight designs were selected and three beams were fabricated for each design using hand layup and vacuum bagging technique. The beams were tested using a four point bending test. The stiffness were calculated and compared with all glass fiber beams. The beams were analyzed using finite element method in Abaqus. It was found that the location of the carbon fiber has an effect on the increase in the stiffness of the beam. Beam with 29.6% carbon fiber by volume gave maximum increase in stiffness. The maximum load carried by the beams showed a different trend. It was observed that the maximum load carrying capacity decreased with increase in the amount of carbon fiber. Carbon fiber effectiveness index (ratio of percentage increase in stiffness of beam and volume percent of carbon fiber) was calculated for each design and it was found that the design D3; which has one layer of carbon fiber on the top and bottom face utilized carbon fiber most effectively.

Committee:

Steven Donaldson, PhD (Advisor); Donald Klosterman, PhD (Committee Member); Thomas Whitney, PhD (Committee Member)

Subjects:

Engineering; Materials Science

Keywords:

Composite Beams; box beams; hybrid composites; glass fiber carbon fiber hybrid composites; Hybrid Beams; Finite element analysis of composites using Abaqus; square beams

Chanda, SoumenduPowertrain Sizing and Energy Usage Adaptation Strategy for Plug-in Hybrid Electric Vehicles
Master of Science, University of Akron, 2008, Electrical Engineering
An energy usage adaptation (EUA) strategy to manage the charge/discharge profile of the energy storage system for plug-in hybrid vehicles is presented in this thesis. The objective of the EUA strategy is to bring the stored energy to a low level at the end of the daily drive cycle, and to limit the number of deep discharge cycles. The EUA algorithm first predicts the energy usage for a given day based on historical usage data. The predicted energy is then compared with the actual energy used and the battery energy available to set the SOC limits in the energy management algorithm. The EUA strategy has been tuned and tested using simulations of both a series and a series-parallel plug-in hybrid vehicle (model) with vehicle control algorithms developed for the purpose. The strategy is shown to improve the fuel economy of the vehicle and to reduce the cost per mile of operation by efficiently using the off board supplied energy. It also helps to extend the life of the battery by limiting the number of deep discharge cycles to no more than one per day. A well-to-wheel analysis of the designed plug-in hybrid is also done using the standard GREET model and through vehicle simulation to investigate the overall efficiency of plug-in hybrid vehicles. The well-to-wheel efficiency of the plug-in hybrids is found to be lower than those of the conventional gasoline and electric vehicles.

Committee:

Iqbal Husain, Dr. (Advisor); Robert J. Veillette, Dr. (Committee Member); Malik Elbuluk, Dr. (Committee Member)

Subjects:

Electrical Engineering

Keywords:

PLUG-IN HYBRID; ENERGY USAGE; drive cycle; hybrid vehicles; predicted energy

Zheng, HuiApplication of the hybrid finite element procedure to crack band propagation
Master of Science (MS), Ohio University, 1987, Civil Engineering (Engineering)

The crack band modeling of the fracture of concrete has so far been numerically studied only for the displacement finite element procedure. In this thesis, a hybrid stress model is applied to problems in the fracture of concrete. The results of this model are compared with those obtained from the displacement method, experimental data and exact solutions. It is shown that the hybrid stress model can provide results closer to the experimental data and less bias in the mesh direction than those obtained from the displacement finite element method.

The propagation of a crack for a concrete beam on an elastic foundation is also studied. A thin-layer interface element is used to simulate the interaction between the beam and elastic foundation.

Committee:

Shad Sargand (Advisor)

Subjects:

Engineering, Civil

Keywords:

Hybrid Finite Element Procedure; Crack Band Propagation; Hybrid Stress Model

Samuel Durair Raj, Kingsly JebakumarModeling, Control and Prototyping of Alternative Energy Storage Systems for Hybrid Vehicles
Master of Science, The Ohio State University, 2012, Mechanical Engineering
Electrochemical batteries are typically considered for secondary energy storage device on hybrid vehicles. Still other forms of energy storage are receiving considerable interest today. In this sense, mechanical or hydraulic system based energy storage are considered as options for realizing low-cost hybrid vehicles. This thesis presents a system dynamics approach to model the energy conversion processes of alternative energy storage systems for hybrid vehicles. A control solution is obtained using Equivalent Consumption Minimization Strategy (ECMS) technique. A simulation study is then conducted using a forward-oriented energy-based vehicle simulator, where the performance of a mechanical and hydraulic energy storage systems are compared for simple vehicle maneuvers. A prototype of the flywheel energy storage system containing flywheel, clutch, continuously variable transmission (CVT) and vehicle inertia is integrated. A rule-based controller was implemented in a rapid control prototyping environment using xPC Target Box, to actuate the clutch and the CVT. Experiments are carried out to characterize the losses associated with components. Energy transfer experiments are conducted and the system model is validated, by comparing the simulation results with the test data. The established experimental set-up can be used for testing various controller designs for the flywheel energy storage system.

Committee:

Marcello Canova (Advisor); Fabio Chiara (Committee Member); Giorgio Rizzoni (Committee Member)

Subjects:

Mechanical Engineering

Keywords:

Flywheel Hybrid; Hydraulic Hybrid; Control Strategy; Prototype

Carroll, Simon A.Strategies for Improving Verification Techniques for Hybrid Systems
Master of Sciences (Engineering), Case Western Reserve University, 2008, Computing and Information Science
In this thesis, we demonstrate techniques to improve upon the Rapidly-exploring Random Tree (RRT) as a tool for planning and verification of hybrid systems. First, we perform experiments that show many planning/verification problems exhibit heavy-tailed behavior, where sampling-based algorithms sometimes require an inordinate number of nodes to solve them. We show that using restarts and multiple trees improves their solution time. Second, we note that for many complex planning/verification problems the hybrid state space admits a natural separation into distinct modes, such that search in one does not help find a path through any other. We use a forest of trees, each tasked with solving a specific mode, to find overall solutions more quickly and with fewer nodes. Third, we solve problems with unpredictable environment changes (because of other agents, unmodeled dynamics, or disturbances) using receding horizon search, where a new path is generated whenever the current path is invalidated.

Committee:

Michael Branicky (Advisor); Guo-Qiang Zhang (Committee Member); M. Cenk Cavusoglu (Committee Member)

Subjects:

Computer Science

Keywords:

Hybrid Systems; RRTs; Rapidly-exploring Random Trees; Heavy-tail; Verification of Hybrid Systems

Spivak, AlexanderA Theoretical Model for Life Cycle Inventory Analysis using a Disaggregated Hybrid Methodology
Doctor of Philosophy, University of Toledo, 2011, Industrial Engineering
Methodologies used to calculate life cycle inventory (LCI) of the functional unit have been developed since the 1970’s to include hybrids of process analysis and input-output methods. Most of the current techniques do not take into account the usage of the product and end of life product aspects, or limit such applications (e.g. Method V of Tiered Hybrid LCI). The goal of this dissertation is to introduce a comprehensive method that takes strong consideration of inventory costs of use and end of life of the functional unit by combining manufacturing and de-manufacturing into the centerpiece of the hybrid analysis. In order to obtain this goal, a new disaggregated methodology is constructed by enhancing currently developed hybrid methods of life cycle inventory compilations. The new methodology is then compared to existing methodologies and to ISO14040 standards. The results of the sample calculations have shown that under right conditions use of disaggregated method will result in significant changes (lowest experimental result: 17% change in CO2 equivalent). The theoretical comparison of ISO14040 requirements had proved that disaggregated hybrid is at least as good on some areas and better in other areas then currently accepted hybrid methods.

Committee:

Matthew Franchetti, Dr. (Committee Chair); Defne Apul, Dr. (Committee Member); Robert Bennett, Dr. (Committee Member); Cyndee L. Gruden, Dr. (Committee Member); Ashok Kumar, Dr. (Committee Member)

Subjects:

Engineering

Keywords:

disaggreaged hybrid; hybrid LCA; LCA; life cycle analysis

Less, Thomas MatthewStructural Performance and Corrosion Resistance of Fiber Reinforced Polymer Wrapped Steel Reinforcing Bars
Master of Science, The Ohio State University, 2013, Civil Engineering
An investigation of the structural behavior and corrosion resistance of hybrid fiber reinforced polymer (FRP) wrapped steel reinforcement bars for use in reinforced concrete structures. The investigation is comprised of a bar analytical model using laminate theory, an in-depth analytical model for reinforced concrete sections, and a series of experimental tests to assess the structural performance and corrosion resistance of the composite bars. A comparison between the analytical model and experimental results was conducted and general design guidelines developed. Using these guidelines, sample designs were completed using hybrid bars, stainless steel bars, and standard epoxy coated steel reinforcing bars. The designs were compared and a life cycle cost (LCC) analysis was performed to assess the economic advantages or disadvantages of the hybrid bars. Conclusions and recommendations for standard practice and design and future research are then presented.

Committee:

Halil Sezen, Dr. (Advisor); Shive Chaturvedi, Dr. (Committee Member); Abdollah Shafieezadeh, Dr. (Committee Member)

Subjects:

Civil Engineering; Materials Science

Keywords:

Reinforced Concrete; Fiber Reinforced Polymer; FRP; Corrosion; Life Cycle Cost; Hybrid; Steel and FRP; Tensile Test; Experimental; Analytical; Concrete; Confinement; Structural Performance; Hybrid Reinforcing Bar; Design; Laminate; Fiber Wrapping

Ryu, YeonsuValidation and Repeatability Testing of a New Hybrid III 6-year-old Lower Extremity
Master of Science, The Ohio State University, 2016, Biomedical Engineering
Although Motor vehicle accidents (MVAs) are reported as the leading cause of death and injury for children over the age of 3, life threatening injuries from the head, neck, and thorax are decreasing due to the advancement of car safety research. Such advancement in car safety brings focus to research on non-fatal, but detrimental injuries that cause life-long disability such as lower extremity injuries (Durbin, 2011, NHTSA, 2012). National Highway Traffic Safety Administration (NHTSA) (2010) reported that lower extremity injury in children between ages 4-7 years old is second in prevalence at 17% following head injury at 38%. In order to gain better understanding of both low and high velocity trauma mechanisms, more pediatric biomechanics research of lower extremity is necessary. However, lack of biofidelity in the lower extremities of the child anthropomorphic test device (ATD) pose challenges to studying the interaction between the body and the interior of the vehicle. Previous studies by Boucher, et al. (2013) evaluated the range of motion and stiffness of the ankle on child volunteers, and unpublished work by Boucher, et al. (2014) developed a new prototype Hybrid III 6-year-old ATD lower extremity. The present project continues to finalize and validate this new instrument. This document is divided into two studies. The first study evaluated the stiffness and impact repeatability of the prototype ATD ankle. Using the standard hand-held universal goniometer and an Isokinetic Dynamometer (Biodex System III), range of motion (ROM) and stiffness of the ankle with various stiffness bumpers in dorsiflexion and plantarflexion were determined. The bumper with the most biofidelic response was chosen for further testing. The ATD ankle was then tested for impact repeatability in the tibia and the ankle using a ram impactor. Results of the dynamometer testing indicated that bumper 80A was most comparable with the child volunteers (Boucher, et al., 2013) with the stiffness of 0.79 Nm/deg and a ROM of 26°. Results of the ram testing indicated repeatable responses especially in the tibia load, tibia moment, and ROM with the maximum coefficient of variance at 2.7%. The ankle stiffness was not as repeatable with a maximum coefficient of variance 15.61%. The second study evaluated impact response of the prototype lower extremity in a realistic and dynamic environment using knee-bolster airbags. The ATD was positioned in a front seat to mimic three worst case scenarios including toes on mid-dashboard, toes on lower dashboard, and feet flat on floor. The impact responses in the femur and tibia were collected and compared with published injury threshold values. The KBA test results indicated that positions with toes on mid-dashboard and feet flat on ground are not injurious to the lower extremity. The position with toes on lower dashboard was concluded to be injurious due to the high bending moments in the tibia. In conclusion, the above studies demonstrate increased biofidelity of the ATD lower extremity. This indicates positive steps towards validating the new design of the Hybrid III 6-year-old ATD ankle.

Committee:

John Bolte, IV (Advisor); Amanda Agnew (Committee Member); Laura Boucher (Committee Member)

Subjects:

Biomechanics; Biomedical Engineering; Biomedical Research

Keywords:

Hybrid III; Hybrid III 6-year-old; 6 year old; ATD; Anthropomorphic Test Device; Lower Extremity; pediatric injury; crash test dummy

Park, JaeyongSafe Controller Design for Intelligent Transportation System Applications using Reachability Analysis
Master of Science, The Ohio State University, 2013, Electrical and Computer Engineering
Intelligent Transportation Systems (ITS) apply well-established technologies in communications, control, and computer hardware and software to increase safety and improve operational performance of the transportation network without expanding the current infrastructure. For many ITS applications, ensuring safety of the traffic participants, including drivers and pedestrians, is one of the most important research initiatives of the Intelligent Transportation Systems Society (ITSS). The ITS applications range from collision avoidance for autonomous or human-driven vehicles to cooperation of multiple vehicles to achieve common goals such as reduced fuel consumption or increased traffic throughput. The main challenges when designing controllers for such systems are the need to consider the close combination of, and coordination between, the system's computational and physical elements. Most of the vehicles nowadays are controlled by tens of or even hundreds of microcontrollers, which communicate via a CAN bus, for electric steering, braking, chassis and body control. Moreover, vehicles interact with other traffic participants including (semi) autonomous vehicles and human-driven cars and also with roadside units through a Vehicle-to-Vehicle (V2V) or Vehicle-to-Infrastructure (V2I) communication, resulting in a large-scale Cyber-Physical System. Thus, traditional control theory that has been devoted to modeling continuous systems cannot adequately model such complex Cyber-Physical Systems, where both continuous (physical plant, e.g., vehicle) and discrete components (computing and communication) closely interacting each other. This thesis studies the design of continuous control laws that satisfy the safety property of the systems and their interfaces with discrete components that abstract human's high-level, decision making process. Our primary goals are to design continuous controllers for ITS applications that by design guarantee the safety property without further verification. First of all, hybrid systems, a class of modeling frameworks which form the foundation for a mathematical approach to Cyber-Physical Systems will be introduced. Then the reachability analysis techniques are developed to compute the exact reachable sets which will then be manipulated to design control laws that satisfy the safety property of the system. As a motivating application, we consider the Adaptive Cruise Control (ACC) system which becomes increasingly popular in commercial vehicles but lacks a fully-automated Collision Avoidance (CA) functionality, thus still leaving the responsibility to human drivers to apply proper braking force. Since the currently available ACC systems are developed mainly for providing drivers comfort and convenience riding, it cannot address the situation where safety should come first. Such situations may include sudden deceleration of a preceding vehicle and cut-in by a slower vehicle, where a rear-end collision is imminent or unavoidable. Thus, an active CA system needs to be developed and fully integrated into the ACC system in order to give more control authority to the vehicle when the driver cannot react fast enough to the imminent collision event. In this regard, the CA problem between the ACC-equipped vehicle (follower) and the preceding vehicle (leader) is formulated as a pursuit-evasion game to take into account the worst case scenario. That is, the leader tries to cause a collision by full braking while the follower tries to avoid it. By solving this game under the assumption that the follower's braking force is larger than that of the leader, the unsafe region can be obtained as a union of sets reachable from a collision set. This means that if the follower is within this unsafe region it cannot avoid a collision regardless of its control effort, i.e., the unsafe region becomes a controlled-invariant set when the leader plays optimally. In other words, the follower can always avoid a collision if it stays outside of the unsafe region for all time. The resulting safe set, complement of the unsafe region, represents the minimum safe distances and serves as a lookup table so that the follower can refer to it and apply an appropriate level of braking. Moreover, the ACC with CA system will be further augmented with a communication capability so that vehicles can interact with other vehicles and maintain a very small gap, preferable several meters, to the preceding vehicles. This can implement Cooperative Adaptive Cruise Control (CACC) for multiple vehicles forming a platoon with a small inter-vehicle spacing in highway traffic, resulting in reduced fuel consumption and increased traffic throughput.

Committee:

Umit Ozguner, Ph.D. (Advisor); Wei Zhang, Ph.D. (Committee Member)

Subjects:

Electrical Engineering

Keywords:

Cyber-physical systems; intelligent transportation systems; hybrid systems; hybrid automata; reachability analysis; level set methods; hamilton-jacobi-isaacs equations; pursuit-evasion game; adaptive cruise control; collision avoidance

Picot, Nathan M.A STRATEGY TO BLEND SERIES AND PARALLEL MODES OF OPERATION IN A SERIES-PARALLEL 2-BY-2 HYBRID DIESEL/ELECTRIC VEHICLE
Master of Science, University of Akron, 2007, Electrical Engineering
The results of implementing a series-parallel control strategy for a heavily-hybridized parallel hybrid-electric vehicle are investigated. Simulation was used to estimate the effects of changing control strategy parameters on fuel economy, drive quality and tail-pipe emissions. A Simulink model of a heavily modified 2005 Chevrolet Equinox test vehicle equipped with a diesel internal combustion engine utilizing exhaust aftertreatments, two electric motors, and a series string of ultracapacitors was used for all simulations. Several control strategies were simulated using various drive cycles that represent a range of driving conditions and driver habits. No a priori drive cycle information was assumed to be available to the controller. The series-parallel control strategy was demonstrated through simulation to improve both fuel economy and drive quality when compared to the parallel control strategy. Further in-vehicle testing is necessary to determine the effects on emissions, but it was shown that choosing the ICE operating point to improve emissions results in near-optimal fuel economy when using either the parallel or the series-parallel control strategy.

Committee:

Robert Veillette (Advisor)

Keywords:

hybrid vehicle control; series-parallel hybrid vehicle; vehicle modeling and simulation; real-time; drivability; fuel economy; emissions

Alalwiat, Ahlam AdnanMass Spectrometry Methods for the Analysis of Biodegradable Hybrid Materials
Doctor of Philosophy, University of Akron, 2015, Chemistry
This dissertation focuses on the characterization of hybrid materials and surfactant blends by using mass spectrometry (MS), tandem mass spectrometry (MS/MS), liquid chromatography (LC), and ion mobility (IM) spectrometry combined with measurement and simulation of molecular collision cross sections. Chapter II describes the principles and the history of mass spectrometry (MS) and liquid chromatography (LC). Chapter III introduces the materials and instrumentation used to complete this dissertation. In chapter IV, two hybrid materials containing poly(t-butyl acrylate) (PtBA) or poly(acrylic acid) (PAA) blocks attached to a hydrophobic peptide rich in valine and glycine (VG2), as well as the poly(acrylic acid) (PAA) and VG2 peptide precursor materials, are characterized by matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS), electrospray ionization mass spectrometry (ESI-MS) and ion mobility mass spectrometry (IM-MS). Collision cross-sections and molecular modeling have been used to determine the final architecture of both hybrid materials. Chapter V investigates a different hybrid material, [BMP-2(HA)2], comprised of a dendron with two polyethylene glycol (PEG) branches terminated by a hydroxyapatite binding peptide (HA), and a focal point substituted with a bone morphogenic protein mimicking peptide (BMP-2). MALDI-MS, ESI-MS and IM-MS have been used to characterize the HA and BMP-2 peptides. Collisionally activated dissociation (CAD) and electron transfer dissociation (ETD) have been employed in double stage (i.e. tandem) mass spectrometry (MS/MS) experiments to confirm the sequences of the two peptides HA and BMP-2. The MALDI-MS, ESI-MS and IM-MS methods were also applied to characterize the [BMP-2(HA)2] hybrid material. Collision cross-section measurements and molecular modeling indicated that [BMP-2(HA)2] can attain folded or extended conformation, depending on its degree of protonation (charge state). Chapter VI focuses on the analysis of alkyl polyglycoside (APG) surfactants by MALDI-MS and ESI-MS, MS/MS, and by combining MS and with ion mobility (IM) and/or ultra-performance liquid chromatography (UPLC) separation in LC-IM and LC-IM-MS experiments. Chapter VII summaries this dissertation’s findings.

Committee:

Chrys Wesdemiotis, Dr. (Advisor); Leah Shriver, Dr. (Committee Member); Adam Smith, Dr. (Committee Member); Sailaja Paruchuri, Dr. (Committee Member); Matthew Becker, Dr. (Committee Member)

Subjects:

Analytical Chemistry; Chemistry

Keywords:

Mass Spectrometry; the Analysis of Biodegradable Hybrid Materials; Hybrid Materials

Wollaeger, James P.ITS in Energy Management Systems of PHEV's
Master of Science, The Ohio State University, 2012, Electrical and Computer Engineering

Intelligent Transportation Systems (ITS) is a broad category of research relating to new technologies that can improve systems in vehicles, such as safety or energy management. The studies in this thesis discuss how energy management systems can be improved with theories and information from ITS research areas. New types of vehicles are entering the marketplace now that include electric vehicles (EV’s), hybrid electric vehicles (HEV’s), and plug-in hybrid electric vehicles (PHEV’s). HEV’s and PHEV’s are a particular challenge to control engineers because of the flexibility of their powertrains. These vehicles contain two power sources, their internal combustion engine and their battery-powered electric motor. The powersplit control problem will be discussed and how optimal control theory can be implemented to optimize the powersplit resulting in lower fuel consumption.

Chapter 2 discusses the areas of ITS that are relevant to the PHEV control problem. These include sourcing geographic data such as road grade and computing the length and geometry of a route to be traversed. Chapter 3 covers the Challenge X vehicle simulator and the dynamic equations that form the vehicle model. The Challenge X vehicle was designed for the 2004 Challenge X competition sponsored by General Motors where student teams competed to convert a small SUV into a hybrid electric vehicle. This simulator was modified from its original form to reflect a prototype plug-in hybrid electric vehicle. This included modifying the battery model to include more capacity and change the cell chemistry to lithium ion from nickel-metal hydride. Chapter 4 includes the details of the powersplit control algorithm implemented, called the Adaptive Equivalent Consumption Minimization Strategy(A-ECMS). A new formulation called the finite horizon adaptive ECMS is introduced and its performance analyzed under varying road load conditions and compared with the global optimal solution from Dynamic Programming.

Committee:

Umit Ozguner (Advisor); Giorgio Rizzoni (Committee Member); Simona Onori (Committee Member)

Subjects:

Automotive Engineering; Electrical Engineering; Energy; Engineering

Keywords:

Hybrid Electric Vehicle; Plug-In Hybrid;HEV;PHEV;ECMS;Equivalent Consumption Minimization Strategy;Finite Horizon;Optimal Control

McDonough, JoshuaSystem Dynamics Modeling and Development of a Design Procedure for Short-term Alternative Energy Storage Systems
Master of Science, The Ohio State University, 2011, Mechanical Engineering
Recovering and storing a vehicle’s kinetic energy during deceleration and the subsequent use of the stored energy during acceleration has lead to significant increases in vehicle efficiency. Current production hybrid electric vehicles (HEVs) convert the energy and store it using electric machines and electro-chemical batteries. While these systems can be configured to provide substantial benefits in addition to kinetic energy recovery, significant limitations exist which hinder the performance and market penetration. Converting mechanical energy to electricity then storing it chemically leads to considerable losses during storage. The path must be followed in the opposite direction during release, compounding the losses. Current HEV batteries, while very effective at storing large quantities of energy, have longevity driven power limitations which drive up cost and weight. As a result of these limitations, investigations have been made into alternative means to recover and store kinetic energy on board vehicles. This thesis investigates two such methods of energy recovery and storage, a hydraulic system with accumulator energy storage and a purely mechanical system with flywheel energy storage. Both systems are of parallel hybrid architecture and offer high power capacity at relatively low cost. The hydraulic system consists of a pump/motor to convert mechanical work to fluid power and a high-pressure accumulator to store the energy. The mechanical system transmits the vehicle’s kinetic energy to a flywheel through changing the ratio of a continuously variable transmission linked between the flywheel and the drivetrain. System dynamics models are created for each of the systems’ components and coupled to allow for analysis over simulated drive cycles. An iterative design method is proposed for both the hydraulic and mechanical systems, based on drive cycle analysis, performance in simulation, and system properties, such as mass and estimated cost. The systems are compared and contrasted with each other in order to evaluate the relative strengths and weaknesses of the various kinetic energy recovery methods.

Committee:

Marcello Canova, PhD (Advisor); Yann Guezennec, PhD (Committee Member)

Subjects:

Automotive Engineering; Mechanical Engineering

Keywords:

hybrid; energy storage; hydraulic; flywheel; system dynamics;

ECKERT, GREGORY WINDSORTHE CREATION OF HYBRID SPACE ARCHITECTURE
MARCH, University of Cincinnati, 2006, Design, Architecture, Art and Planning : Architecture (Master of)
Today, people use the computer as part of their daily lives, whether it is at work, home, or in the palm of their hands. The increased popularity of online access has changed society in the areas of communication, commerce, research, and entertainment. As society changes, architecture will change with it. The retail industry is ready to undergo a transformation. Thus, this thesis explores the integration of virtual and physical environments to achieve a unique way of retailing that provides the customer with an enhanced experience, convenient service, and personalized stores. Communication among customers includes access to a virtual world, which allows them to interact with distant locations and individuals whether in the main physical store, virtually from a home computer, or from a branch location. Technology gives the retailer the ability to change quickly, access a larger customer base, and personalize advertising to individuals. Accordingly, it is hypothesized that the new retail environment will be a collection of inter-connected retail communities, both real and virtual, interacting in ways previously believed to be science fiction.

Committee:

Barry Stedman (Advisor)

Keywords:

hybrid,; virtual,; real space,; retail,; integrated,; experience,; controlled user,; circulation.

Immaneni, TrivikramA HYBRID APPROACH TO RETRIEVING WEB DOCUMENTS AND SEMANTIC WEB DATA
Doctor of Philosophy (PhD), Wright State University, 2008, Computer Science and Engineering PhD
The Semantic Web has been evolving into a property-linked web of RDF data, conceptually divorced from (but physically housed in) the World Wide Web of hyperlinked documents. Data Retrieval techniques are typically used to retrieve data from the Semantic Web while Information Retrieval techniques are used to retrieve documents from the Hypertext Web. Conceptually unifying the two webs enables the exploitation of their interconnections resulting in benefits to both data and document retrieval. Towards this end, we present the Unified Web model that integrates the two webs and formalizes the structure and the semantics of their interconnections. We present a hybrid approach to retrieving data and documents that is enabled by this unification. We specify the Hybrid Query Language that embodies the approach and the system SITAR that implements it.

Committee:

Krishnaprasad Thirunarayan (Advisor)

Subjects:

Computer Science

Keywords:

Semantic Web; Information Retrieval; Hybrid Query Language; Document Retrieval; Data Retrieval

Ranjan, RajeshSurface Modification of Silica Nanoparticles
Doctor of Philosophy, University of Akron, 2008, Polymer Science

Surface modification of nanosized silica particles by polymer grafting is gaining attention. This can be attributed to the fact that it provides a unique opportunity to engineer the interfacial properties of these modified particles; at the same time the mechanical and thermal properties of the polymers can be improved. Controlled free radical polymerization is a versatile technique which affords control over molecular weight, molecular weight distribution, architecture and functionalities of the resulting polymer. Three commonly used controlled free radical polymerizations include nitroxide- mediated polymerization (NMP), atom transfer radical polymerization (ATRP) and reversible addition fragmentation transfer (RAFT) polymerization. ATRP and RAFT polymerization were explored in order to modify the silica surface with well-defined polymer brushes.

A novel click-functionalized RAFT chain transfer agent (RAFT CTA) was synthesized which opened up the possibility of using RAFT polymerization and click chemistry together in surface modification. Using this RAFT CTA, the surface of silica nanoparticles was modified with polystyrene and polyacrylamide brushes via the “grafting to” approach. Both tethered polystyrene and polyacrylamide chains were found in the brush regime. The combination of ATRP and click chemistry was also explored for surface modification.

A combination of RAFT polymerization and click chemistry was also studied to modify the surface via the “grafting from” approach. Our strategy included the (1) “grafting from” approach for brush formation (2) facile click reaction to immobilize the RAFT agent (3) synthesis of R-supported chain transfer agent and (4) use of the more active trithiocarbonate RAFT agent. Grafting density obtained by this method was significantly higher than reported values in the literature.

Polystyrene (PS) grafted silica nanoparticles were also prepared by a tandem process that simultaneously employs reversible addition fragmentation transfer (RAFT) polymerization and click chemistry. The click reaction doesn’t interfere with RAFT polymerization. With a suitable choice of a Cu(I) catalyst, it is possible to perform both RAFT polymerization and click chemistry together. In a single pot procedure, azide-modified silica, an alkyne-functionalized RAFT agent and styrene were combined to produce the desired product. As deduced by thermal gravimetric and elemental analysis, the grafting density of PS on the silica in the tandem process was intermediate between the “grafting to” and “grafting from” techniques. Relative rates of RAFT polymerization and click reaction were altered to control grafting density.

ATRP was also used to modify the surface of silica nanoparticles via the “grafting from” approach. The surfaces of silica with homopolymers and diblock copolymers brushes were modified using surface initiated ATRP. The polymer grafted silica particles were characterized by FT-IR, TGA, XPS and elemental analysis.

Committee:

Roderic Quirk, PhD (Advisor); Colleen Pugh, PhD (Committee Chair); Ali Dhinojwala, PhD (Committee Member); Scott Collins, PhD (Committee Member); Bi-min Zhang Newby, PhD (Committee Member)

Subjects:

Polymers

Keywords:

silica; nanoparticle; polymer brush; surface modification; grafting density; hybrid nanopartcles

Mantravadi, Siva Rama PrasannaModeling, Simulation & Implementation of Li-ion Battery Powered Electric and Plug-in Hybrid Vehicles
Master of Science in Engineering, University of Akron, 2011, Electrical Engineering

The modeling, simulation and hardware implementation of a Li-ion battery powered electric vehicle are presented in this thesis. The results obtained from simulation and experiments were analyzed to develop the control algorithm for the vehicle. An existing electric vehicle was reengineered with a new Li-ion battery pack and an advanced control strategy. The implementation platform is a Solectria E-10 electric vehicle which was originally powered with a Lead acid battery pack.

A simulation model of the Solectria E-10 electric vehicle was first developed for vehicle simulation using various standard drive cycles. The supervisory control strategy was first developed and tested in simulation before it was implemented on actual hardware. A Power Save feature was developed to limit the vehicle power demand upon the driver request to increase the zero emissions vehicle range of the electric vehicle. Simulations were used to demonstrate the effectiveness of Power Save feature and it was shown that the range of the electric vehicle can be extended.

The feasibility for plug-in hybrid vehicle conversion of the developed electric vehicle to extend the range of the electric vehicle beyond its zero emissions driving range was studied through simulation. A control algorithm for plug-in hybrid vehicle was developed and simulated.

Committee:

Iqbal Husain, Dr. (Advisor); Tom Hartley, Dr. (Advisor); Malik Elbuluk, Dr. (Committee Member); Yilmaz Sozer, Dr. (Committee Member)

Subjects:

Electrical Engineering

Keywords:

Modeling Simulation and Implementation of Li-ion Battery Powered Electric and Plug-in Hybrid Vehicles

Sharma, Oruganti PrashanthA practical implementation of a near optimal energy management strategy based on the Pontryagin's minimum principle in a PHEV
Master of Science, The Ohio State University, 2012, Electrical and Computer Engineering
This thesis presents the optimal control problem of energy management in a plug-in hybrid electric vehicle. Review of the literature suggests the need for a methodology which follows a blended strategy unlike the traditional charge depleting - charge sustaining (CD-CS) strategy for state of charge of the battery. Many present blended strategies require a-priori knowledge of the driving mission which is obtained by prediction. The performance of these strategies again depends on the prediction algorithms and often end up being sub-optimal in implementation. There is a need for an energy management strategy that provides near optimal results with minimal information about the driving mission. This thesis proposes one such controller. Knowledge of the optimal trajectories under various driving conditions is obtained by implementing a Pontryagin's Minimum Principle (PMP) based energy management scheme. With this knowledge, a practical implementable controller is proposed which performs with near optimal results under different driving missions. A comparison of the optimal PMP solution, the practical controller solution and the traditional CD-CS solution is done to conclude this work.

Committee:

Giorgio Rizzoni, PhD (Advisor); Yann Guezennec, PhD (Advisor); Simona Onori, PhD (Advisor); Mahesh Illindala, PhD (Committee Member)

Subjects:

Alternative Energy; Automotive Engineering; Electrical Engineering; Mechanical Engineering

Keywords:

PHEV; HEV; hybrid electric; optimal control; pontryagins minimum principle; control; energy management strategy; optimization

van Graas, FrankHybrid GPS/LORAN-C: A next-generation of sole means air navigation
Doctor of Philosophy (PhD), Ohio University, 1988, Electrical Engineering & Computer Science (Engineering and Technology)

This paper describes a new technique that hybridizes the NAVSTAR Global Positioning System (GPS) and the Long Range Navigation System,LORAN-C, based on a generic pseudorange processing technique. The concept, theoretical analysis, and justification of a hybrid GPS/LORAN-C system are presented, along with a scheme for meeting sole means of navigation requirements. Following the design and modeling phase, a prototype hybrid GPS/LORAN-C receiver was developed and implemented. The hybrid GPS/LORAN-C receiver concept was proven through an actual flight test, which was referenced to a Differential GPS truth trajectory. The hybrid system has the potential to meet all requirements for a next generation of sole means of air navigation for the conterminous United States.

Committee:

Richard McFarland (Advisor)

Keywords:

hybrid GPS/LORAN-C; air navigation; navigation system; NAVSTAR Global Positioning System

Koshal, SanjivHybrid system GMSK digital receiver implementation in real time
Master of Science (MS), Ohio University, 1994, Electrical Engineering & Computer Science (Engineering and Technology)

Hybrid system GMSK digital receiver implementation in real time

Committee:

Frank van Graas (Advisor)

Keywords:

Hybrid system; GMSK digital receiver; Implementation in real time

Lee, MelanieReconceptualizing Masculinized L/logos, Re(Image)ining the Rhetorical Feminine in Composition
Doctor of Philosophy (PhD), Ohio University, 2011, English (Arts and Sciences)

Absence of the rhetorical feminine from our Western tradition is an ideological, theoretical problem whose consequences manifest in material, practical ways that affect how we teach writing. This dissertation, the first hybrid manuscript of its kind at Ohio University, examines relationships between mythos, logos, and the eikon (icon) in light of ancient rhetorics that depict powerful feminine entities and woman rhetors engaging in public, rhetorical performativity. They suggest our rhetorical origins may be as visual as textual. But the feminine authority ancient rhetorics convey is diminished, masculinized, and resignified in the West through the social construction of masculinized L/logos. As a result, once powerful feminine rhetorics disappear from our rhetorical tradition. I question the rhetorical feminine’s absence in light of images that show woman rhetors engaging in deliberative, epideictic, and forensic performativity long before Aristotle taxonomizes these terms. I argue that rhetorical and religious authorities historically entwine through masculinized L/logos and the institutionalization of what I call patri-theogony--a blend of sacred and secular patriarchal ideology that custom and laws enforce which coincides with the supposed mythos-to-logos cultural shift--that supports the inception of a masculinized rhetoric. Lasting academic consequences result: feminine authority is rendered invisible, affecting our discipline, our language, and our entire social order.

For example, feminization of composition follows from masculinization of rhetoric in the structure of masculinized L/logos. Rhetorical inequity between women and men places what Robert Connors calls “feminized” writing faculty in positions of responsibility without authority. In these positions, feminized writing faculty enact what I call the trope of the schoolmarm: disempowered authority figures, “mythologized mother-teachers” separated from once powerful rhetorical feminine roots, they practice current traditional pedagogy as a compensatory strategy for coping with overworkloads. In this way, traditional college writing classrooms reflect the structure of masculinized L/logos and suppress the rhetorical feminine. Rhetorical performativity combined with writing faculty overload suppresses feminized writing faculty’s dialogue with students and supports silencing of the rhetorical feminine. Instead of engaging students in conversation about their ideas, overloaded schoolmarms echo masculinized L/logos in correctness-focused, “God/truth voice” (Elbow) comments that discourage revision and maintain rhetoric of distance between dominant, masculinized rhetoric and submissive, feminized composition. Likewise, epistemic inequity between visual and verbal rhetorics follows from masculinization of the word and feminization of the image, subordinating image to word in the making of new knowledge. Yet visual rhetoric from antiquity through modernity depicts Rhetorike as a formidable, feminine, linguistic warrior-hero that contests this paradigm. Renegotiating this ideological and material dissonance requires ideological, material re(image)ining.

I claim that the icon is the site where the generative essence mythos and logos share overlap. My dissertation integrates icons of rhetorical feminine authority, blending visual rhetoric with the(a)logy in a hybrid text to re(image)ine and reinscribe the rhetorical feminine in masculinized L/logos, creating a God/Ess L/logos that renegotiates visual-verbal boundaries. I suggest that our rhetorical origins may be as pictorial as textual, our rhetoric and composition is performative, and our visions of rhetorical authority should be androgynous and polymorphic. These reconceptions open new possibilities for the teaching and learning of writing.

Committee:

Jennie Nelson, PhD (Committee Chair); Jennie Klein, PhD (Committee Member); Albert Rouzie, PhD (Committee Member); Mara Holt, PhD (Committee Member)

Subjects:

Rhetoric

Keywords:

masculinized L/logos; absent rhetorical feminine; mythos, logos, icon; performative rhetoric and composition; trope of the schoolmarm; rhetoric of distance; God/Ess L/logos; image integrated text; rhetorical feminine authority; hybrid dissertation form

Wei, XiModeling and control of a hybrid electric drivetrain for optimum fuel economy, performance and driveability
Doctor of Philosophy, The Ohio State University, 2004, Mechanical Engineering
Automotive manufacturers have been striving for decades to produce vehicles which satisfy customers’ requirements at minimum cost. Many of their concerns are on fuel economy, road performance and driveability. A hybrid electric vehicle (HEV) is one of the most promising alternatives to a conventional engine-powered vehicle which satisfies the above requirements. Investigations indicate that how to allocate the total tractive force between the engine and the electric machine has significant influences on vehicle fuel economy, performance and driveability. Therefore, designing an optimal control strategy which considers all three criteria is of great interest. Model based control design requires control oriented models and the complexity of these models are determined by their applications. Since the control strategy is developed in two steps (finding the solution for the best fuel economy and performance first and then taking driveability into consideration), two models, i.e., the quasi-static model and the low-frequency dynamic model are built for each step in the control design. Defining objective metrics for vehicle fuel economy, performance and driveability is also very important. Evaluations in both simulations and real vehicles require objective and quantitative metrics. Vehicle fuel economy is estimated under various driving cycles. Performance criteria consist of acceleration performance, gradeability and towing capability. Driveability measures deal with pedal responsiveness, operating smoothness and driving comfort, which include interior noise level, jerk, tip-in/tip-out response, MTVV, acceleration RMS and VDV. The optimal control solution is then found hierarchically with the help of Pontryagin’s minimum principle. Fuel economy optimization contains three steps: finding the optimal solution for known constant power requests, for known time-varying power requests and for unknown time-varying power requests with short-term predictions. An innovative interpretation of the minimum principle is applied when minimizing fuel consumption for the vehicle with constant battery parameters and fixed CVT ratio under constant power requests. This so-called sliding optimal control which switches between two control values has been theoretically proven to be the optimal solution. The control strategy developed with the minimum principle is compared with a simple heuristic one and simulation results demonstrate an improvement on vehicle fuel economy.

Committee:

Giorgio Rizzoni (Advisor)

Subjects:

Engineering, Mechanical

Keywords:

system dynamics; modeling and control of automotive powertrains; hybrid electric vehicles; driveability objective metrics

Next Page