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Sloan, Bethany L.Engineering at Miami
Bachelor of Science in Applied Science, Miami University, 2007, School of Engineering and Applied Science - Computer Engineering
This thesis explores Engineering at Miami University through personal reflection and comparisons to other Engineering schools in Ohio. The goal of the thesis is to provide Miami’s School of Engineering and Applied Science (SEAS) with suggestions for improvement based on my experiences in undergrad and survey data from Engineering students at Miami University, Ohio State University, University of Cincinnati and Wright State University. Specific areas of interest are the schools’ Introduction to Engineering courses as well as strengths and weaknesses of each Engineering program.

Committee:

C. Chen (Advisor)

Keywords:

Miami Engineering; engineering data; engineering survey; introduction to engineering; engineering comparisons; Ohio engineering; engineering; engineering experience; Miami university engineering; engineering statistics; solar powered car cooling

Rinehart, Aidan WalkerA Characterization of Seal Whisker Morphology and the Effects of Angle of Incidence on Wake Structure
Master of Science in Mechanical Engineering, Cleveland State University, 2016, Washkewicz College of Engineering
Seal whiskers have been found to produce unique wake flow structures that minimize self-induced vibration and reduce drag. The cause of these wake features are due to the peculiar three-dimensional morphology of the whisker surface. The whisker morphology can be described as an elliptical cross section with variation of diameter in the major and minor axis along the length and, angle of incidence, rotation of the elliptical plane with respect to the whisker axis, α at the peak and β at the trough. This research provided a more complete morphology characterization accomplished through CT scanning and analysis of 27 harbor and elephant seal whisker samples. The results of this study confirmed previously reported values and added a characterization of the angle of incidence finding that the majority of angles observed fall within ±5° and exhibit a random variation in magnitude and direction along the whisker length. While the wake effects of several parameters of the whisker morphology have been studied, the effect of the angle of incidence has not been well understood. This research examined the influence of the angle of incidence on the wake flow structure through series of water channel studies. Four models of whisker-like geometries based on the morphology study were tested which isolate the angle of incidence as the only variation between models. The model variations in angle of incidence selected provided a baseline case (α = β = 0°), captured the range of angles observed in nature (α = β = -5°, and α = β = -15°), and investigated the influence of direction of angle of incidence (α = -5°, β = -5°). The wake structure for each seal whisker model was measured through particle image velocimetry (PIV). Angle of incidence was found to influence the wake structure through reorganization of velocity field patterns, reduction of recovery length and modification of magnitude of Tu. The results of this research helped provide a more complete understanding of the seal whisker morphology relationship to wake structure and can provide insight into design practices for application of whisker-like geometry to various engineering problems.

Committee:

Wei Zhang, PhD (Advisor); Ibrahim Mounir, PhD (Committee Member); Shyam Vikram, PhD (Committee Member)

Subjects:

Aerospace Engineering; Aquatic Sciences; Engineering; Fluid Dynamics; Mechanical Engineering

Keywords:

seal; whisker; PIV; biomimicry; fluid dynamics; particle image velocimetry; bio-engineering; engineering; mechanical engineering; aerospace engineering; experimental fluid dynamics;

Tan, Adrian HadiprionoWhile Stands the Colosseum: A Ground-Up Exploration of Ancient Roman Construction Techniques using Virtual Reality
Doctor of Philosophy, The Ohio State University, 2015, Civil Engineering
The construction of ancient monuments, such as the Colosseum (Coliseum) of Rome, was an enigmatic and complex process that has never been explored. Most sources about the largest ancient amphitheater focus on the historical and archaeological aspects. This dissertation seeks to elaborate on the construction methods of the Colosseum using engineering principles, based on which a digital reconstruction of the most likely of these methods in the form of a virtual-reality simulation – a process that has never been attempted before in the construction study of this ancient monument – was created. This dissertation presents a state-of-the-art and comprehensive exploration of the construction of the Colosseum, deriving and compiling information from both personal observations and a number of different historical and archaeological sources as well as findings from the monument itself. The construction processes of the Colosseum can be divided into five distinct stages: the pre-plan and plan, which details how the site of the construction was selected and drafted; the substructure, involving an analysis the best and safest alternative for constructing the foundation of the building; the hypogea or underground chambers, which provide chambers beneath the arena to house the gladiators and other contestants; the superstructure, the majority of the building which could have been built in several different ways, each of which consists of a number of organized stages; and the velarium, or roof awning, which can be installed in several different ways, resulting in different ranges of protection from the weather. After the different construction methods that may be employed for all of these stages are compared, a number of possible pathways of construction are established, and one of them is selected as the most plausible given the construction practices of the ancient Romans. The findings of the construction methods of such a majestic structure are not complete without simulations using state-of-the-art technology; virtual reality in particular is a prime candidate for this prospect. Thus, the means of creating a virtual model for presenting the construction process, which is known as the graphics pipeline, are researched and displayed in detail. The different stages for the creation process of the simulation are the possible schemes of presenting the digital assets created; the software and hardware selection, which details the possible programs that will be used in the graphics pipeline; and the implementation of the graphics pipeline itself to create the completed model, stages, and user interface. Overall, this combination of history and technology forms a pioneering and comprehensive model which details the construction processes of the Colosseum for a modern audience, and demonstrates that the hitherto unexplored engineering aspects deserve as much admiration as the monument itself.

Committee:

Frank Croft, Jr. (Advisor); Tarunjit Butalia (Committee Member); Rachel Kajfez (Committee Member)

Subjects:

Archaeology; Architecture; Civil Engineering; Classical Studies; Computer Science; Engineering; History

Keywords:

archaeology; architecture; civil engineering; engineering; Colosseum; Coliseum; computer graphics; computer-aided design; construction; digital graphics; digital simulation; history of engineering; Rome; Roman Empire; virtual reality

Carpenter, Wesley AEngineering Creativity: Toward an Understanding of the Relationship between Perceptions and Performance in Engineering Design
Doctor of Philosophy, University of Akron, 2016, Secondary Education
Few studies have focused on perceptions of creativity in engineering. Previous researchers have tended to focus on perceptions concerning the degree to which creative thinking is emphasized in the classroom, rather than on whether students value creativity as an important part of the engineering design process. Moreover, the relationship between students’ perceptions of the importance of creative thinking in engineering design and their creative performance has not been investigated. Given the value placed on the ability of an engineer to think creatively, it is important to understand how engineering students perceive creativity as it relates to the engineering design process and whether such perceptions have the potential to influence their ability to think creatively during the engineering design process. In this mixed-methods study, perceptions related to four primary themes: students’ perceptions of (a) the definition of creativity with respect to engineering design, (b) the importance of creativity during engineering design, (c) the extent to which creativity was developed throughout the engineering program, and (d) their own creative abilities. Themes were compared among eight engineering students who scored at the extreme ends of the Creative Engineering Design Assessment (CEDA). In addition, perceptions were gathered from 12 mechanical engineering faculty in order to compare their perceptions of creativity in the mechanical engineering program to those of the students. The findings of this study support predictions made by applying the expectancy-value theory, which holds that students who value creativity in engineering design and confidently believe they have the ability to be creative are more likely to be creative in various engineering design scenarios. Further, all students interviewed shared the perception that the mechanical engineering program did little to encourage and develop creative-thinking skills; however, students agreed the program developed the foundational knowledge necessary for creative thought. These findings may be useful for engineering educators as well as for guiding future researchers in the areas of engineering education and engineering creativity.

Committee:

Nidaa Makki, Dr. (Advisor); Susan Kushner Benson, Dr. (Committee Member); Wondimu Ahmed, Dr. (Committee Member); Edward Evans, Dr. (Committee Member); Francis Broadway, Dr. (Committee Member)

Subjects:

Education; Engineering

Keywords:

creativity; engineering education; engineering design; perceptions; expectancy-value theory; mechanical engineering

Foldes, Stephen ThomasCommand of a Virtual Neuroprosthesis-Arm with Noninvasive Field Potentials
Doctor of Philosophy, Case Western Reserve University, 2010, Biomedical Engineering

Assistive devices, such as motor neuroprostheses, have been developed to help restore function for individuals with tetraplegia. For individuals with severe paralysis, command sources for assistive devices are limited to muscle activity and/or movements of the head and face. These commands can impede eating, talking, and other activities. Incorporating signals from the brain may be a valuable way to augment the command options for complex devices.

The attempted movements of body parts generate characteristic changes in field potentials over brain areas associated with those body parts. These movement-related changes can be recorded from the scalp and used to control an assistive device. Most previous studies using movement-related field potentials as a command source have been focused on the abstract control of computer cursors and not specifically focused on restoring arm and hand function using neuroprostheses.

We developed new spatial filtering techniques to help separate the cortical activities associated with the movement and rest of different body parts. Using these novel spatial filters, we demonstrated that two-dimensional movement of a ‘virtual upper-extremity neuroprosthesis’ can be controlled using electroencephalography (EEG) signals that are modulated by the attempted movement of two body parts which are spread apart in the motor homunculus (i.e. hand and feet).

The attempted movement of the feet and hand was an abstract command strategy using body parts unrelated to the desired device movement. A more natural command strategy of using the attempted movements of arm and hand joints was evaluated as a more intuitive way to control the same joints of the neuroprosthesis. Using a more natural command strategy, we demonstrated that individuals with tetraplegia were able to intuitively control the grasp of a virtual hand using movement-related field potentials associated with hand extension and relaxation. When expanding intuitive control to combinations of the elbow, shoulder, and hand together, our offline analysis showed a reduction in decoding accuracy over abstract command strategies in able-bodied individuals but equivalent or improved accuracy in the tetraplegic participants.

Demonstrating real-time control of a virtual upper-limb neuroprosthesis using EEGs is an important step towards the clinical implementation of brain-controlled motor neuroprostheses.

Committee:

Dawn M. Taylor, PhD (Advisor); Robert Kirsch, PhD (Committee Chair); Cameron McIntyre, PhD (Committee Member); Kenneth Gustafson, PhD (Committee Member); Wojbor Woyczynski, PhD (Committee Member)

Subjects:

Biomedical Engineering; Neurosciences; Rehabilitation

Keywords:

Brain Machine Interfacing; Brain Computer Interfacing; Electroencephalography; Functional Electrical Stimulation; Neuroprosthesis; Spatial Filtering; Rehabilitation Engineering; Neural Engineering; Biomedical Engineering; Signal Processing

Tan, Adrian HadiprionoA Computer-Generated Model of the Construction of the Roman Colosseum
Master of Science, The Ohio State University, 2012, Civil Engineering

This research focuses on the construction process of the Colosseum, the famous ancient Roman amphitheater, by digitally recreating the step-by-step processes that would have been involved in the construction process, demonstrating that the process of retracing the construction of such a large and complex monument presents a variety of challenges. Computer-generated imagery, or CGI, has long been used to recreate ancient structures based on literature and archaeological evidence. Most of the simulations that are generated, however, focus primarily on the appearance of the structures upon completion and during use. Given enough data, computer graphics can serve as an effective tool in simulating the construction of ancient monuments as well, which is demonstrated via the digital (re)construction of the Colosseum as mentioned previously. Through extensive research and on-site analysis, enough dimensions for the construction process and the architectural features and concepts that such a simulation will likely entail can be obtained to create relatively accurate representations, which will in turn serve as a breeding ground for theories concerning their design, construction, and ability to withstand the test of time.

In this case, the background of the study is presented in the form of the history of Roman architecture in general and especially of theaters such as the amphitheater, the category which the Colosseum belongs to. This clarification provides a starting point for the research, and forms the precedent for most of the ideas that will be employed. The background of the simulation includes software, in this case Autodesk Inventor, which provides an ideal balance of user-friendliness and complexity handling. Coupling this is a structural analysis of the monument that provides the key dimensions and features that are present in the actual model. With this in mind, the creation of the model, using the functionality of the user interface, is compared to the actual construction, revealing a critical dissimilarity. The model renders the superstructure as one continuous feature, with all the levels being created at once instead of in stages as per the original construction process. In addition to this setback, the modeling procedure is also affected by other complications, most notably the linear correlation between complexity and render time. Large amounts of features such as those seen in the Colosseum would cause the program to potentially stall in a bid to process the corresponding amount of data, which may be due to the dissonance between the computation capabilities of the hardware and the functionality of the software.

Technical complications aside, the simulation also shows mixed results conceptually. With technology advanced enough to handle the complexity, the construction stages could theoretically be rendered, but they must be reverse-engineered from the completed model. This precludes using the simulation as a direct influence in both historical studies and civil/green engineering, and furthermore, it fails to take into account the labor, expenses, and sustainability issues regarding the structure. Thus, this simulation is best applied not as a direct reference, but rather as a demonstration of the concepts behind it.

Committee:

Franklin Croft (Advisor); William Wolfe (Committee Member); Richard Freuler (Committee Member)

Subjects:

Civil Engineering; Computer Science

Keywords:

CGI; computer graphics; computer-generated imagery; digital modeling; digital model; simulation; Colosseum; monument; Roman; ancient Rome; construction; engineering; civil engineering

lahiry, ashwinDeveloping Molecular Tools for Applications in Metabolic Engineering and Protein Purification
Doctor of Philosophy, The Ohio State University, 2017, Microbiology
Biotechnology is an important field of science that utilizes the principles of biology and engineering to build applications in multi-disciplinary research areas. This dissertation discusses the development of molecular tools in two such research areas: 1) industrial biotechnology and 2) medical biotechnology. Chapters 2 and 3 of this dissertation focus on the development of a multi-targeting small regulatory RNA (sRNA) as a potentially useful tool for metabolic engineering applications in industrial biotechnology. sRNAs can govern gene expression by base-pairing with the translation initiation regions (TIRs) of mRNAs. These sRNAs can be engineered to target the TIRs of non-cognate mRNAs by altering their antisense sequences. Due to their modular, tunable and portable nature, they possess unique regulatory qualities for optimizing metabolic pathways. In Chapter 2, an Escherichia coli-based genetic system was created for the development of dual-acting sRNA variants. These variants were built on the DsrA scaffold, a well-characterized multi-acting E. coli sRNA and assayed for the regulation of two separate TIRs fused to independent reporter genes. Expression of the sRNA and each reporter mRNA was independently controlled, and regulatory effects were quantified in vivo using a microtiter plate assay. Using this system, semi-rationally designed DsrA variants were screened in E. coli for their ability to simultaneously regulate two key TIRs from the Clostridium acetobutylicum n-butanol synthesis pathway. In Chapter 3, this system was utilized to successfully design and test the functionality of DsrA variants in two industrially relevant microorganisms, Bacillus subtilis and Clostridium acetobutylicum. This study demonstrates the value of the genetic system and the sRNA scaffold for designing DsrA variants that specifically target desired mRNAs, and thus provides a platform for retargeting and characterizing multi-acting sRNAs for metabolic engineering applications. Chapter 4 discusses the development of a self-cleaving affinity tag for the purification of recombinant proteins and has applications in medical biotechnology. Process development of new recombinant biotherapeutic proteins involves complex optimization and scale up based on the characteristics of each protein. There is no simple, low-cost platform that can be utilized to purify these diverse proteins. Thus, it is desirable to create an affinity tag-based platform for purification of any recombinant protein, but with the requirement that the purified protein be tagless and traceless. Consequently, our lab has developed a pH-controllable self-cleaving tag based on the Npu DnaE intein from Nostoc punctiforme for affinity-based purification of recombinant proteins. Previous work done with self-cleaving inteins has shown that the target protein residues (extein residues) at the cleavage junction can strongly affect cleavage kinetics of the tag. Therefore, in Chapter 4, the extein dependence of this tag is characterized using model (eGFP) and biotherapeutic (streptokinase (SK) and granulocyte colony stimulating factor (GCSF)) proteins. Through these studies, N-terminal extein residues that result in accelerated or diminished cleavage kinetics were identified. An eGFP model system was also established to predict the effect of the primary extein sequence on the cleavage kinetics of this tag. Finally, the information from this study was utilized to improve cleavage kinetics of the tag with GCSF.

Committee:

David Wood, Dr. (Advisor)

Subjects:

Microbiology

Keywords:

Biotechnology; sRNA engineering; metabolic engineering; self-cleaving tags; protein purification platform; inteins

Raja, Muneeb MasoodExtended Kalman Filter and LQR controller design for quadrotor UAVs
Master of Science in Electrical Engineering (MSEE), Wright State University, 2017, Electrical Engineering
A quadrotor is a unique class of UAVs with vertical take off and landing (VTOL) capability and has attracted significant attention due to its importance in various applications. This thesis presents the design and experimental implementation of Extended Kalman Filters (EKFs) to estimate the states of a quadrotor and a Linear Quadratic Regulator (LQR) controller with integral action to meet the desired control objectives. In case of the Extended Kalman Filters, two different situations are considered: (1) all the states including the Inertial Measurement Unit (IMU) biases are estimated; (2) only the attitude, altitude, and vertical velocity are estimated. The second case is added as a safety feature to provide enough feedback signals to stabilize and land the quadrotor in the event of a position measurement loss, e.g. from a GPS due to jamming. A double loop control structure is implemented using an LQR controller with integral action, the inner loop contains the attitude and the altitude control, and the outer loop consists of x and y translational positions control. Finally, some preliminary results on the integration of C codes with Simulink using C MEX S-functions is described. A C library of a laser rangefinder sensor is transferred to a C MEX S-function to generate a 2D map of the environment using the laser sensor distance measurements to identify obstacles present within the range of the sensor. The concept of multi-threading and the integration of pthread library with Simulink using C MEX S-function are also described.

Committee:

Xiaodong Zhang, Ph.D. (Advisor); Kuldip Rattan, Ph.D. (Committee Member); Jonathan Muse, Ph.D. (Committee Member)

Subjects:

Aerospace Engineering; Electrical Engineering

Keywords:

electrical engineering; aerospace engineering

Tolle, John E.The distribution of vehicular headways : a stochastic model /
Doctor of Philosophy, The Ohio State University, 1969, Graduate School

Committee:

Not Provided (Other)

Subjects:

Engineering

Keywords:

Traffic flow;Traffic engineering;Traffic regulations;Traffic engineering

Hanes, Rebecca JMultidisciplinary modeling for sustainable engineering design and assessment
Doctor of Philosophy, The Ohio State University, 2015, Chemical Engineering
Design and assessment activities have traditionally been performed with respect to a relatively narrow analysis boundary and without accounting for influences from or on the world outside the boundary. This ``all other things being equal'' mindset results in tractable, generally solvable problems, but it precludes the detection of externalities, consequences that manifest outside the analysis boundary. From a sustainability perspective, externalities - whether they affect the environment, society, the economy, or other systems - cannot be ignored. Moreover, many externalities lead in turn to feedback effects, often negative, on the system of interest. Failing to account for these effects can result in decisions that appear economically, environmentally, or otherwise optimal within a narrow analysis boundary but are sub-optimal or simply incorrect when a larger perspective is taken. To anticipate externalities and avoid the unpleasant surprises they lead to, it is critical to use a holistic perspective for sustainable design and assessment. While this is not a novel concept, to date most efforts towards sustainable design and assessment have been made within single fields of study, including engineering, economic analysis and life cycle assessment. The models used within each discipline are well-suited to the traditional, narrow analysis boundary but frequently capture systems outside that boundary in a simplistic and even unrealistic fashion. This dissertation posits that for sustainability applications, a holistic perspective is best accomplished by combining modeling techniques and other methods from a variety of previously disparate disciplines. These various techniques each have shortcomings and advantages that are often complementary. Combining models from multiple disciplines thus offers an opportunity to create a widely applicable, integrated method with all of the advantages and relatively few of the shortcomings of each individual approach. This dissertation addresses the need for multidisciplinary modeling in sustainability applications. Two methods for sustainable assessment, both of which combine mathematical and statistical modeling with life cycle assessment, are developed. Regression streamlining applies linear regression and model cross-validation techniques to streamlined life cycle assessment, resulting in a simple and intuitive way to generate streamlined life cycle inventories as well as estimates of the error in the streamlined inventories relative to a full inventory. The Comprehensive Allocation Investigation Strategy (CAIS) is a calculation procedure for modeling life cycle inventories as functions of allocation decisions. The results can be used to detect situations in which one life cycle appears environmentally superior to another due to allocation decisions rather than differences in the inventories. The final contribution of this dissertation is the process-to-planet (P2P) modeling framework for sustainable engineering applications. Several applications of the P2P framework to engineering design are presented, with the conclusion that the P2P framework results in environmentally superior designs compared to conventional sustainable design methods. The P2P modeling approach also offers an opportunity to integrate fundamental engineering models with macro-economic equilibrium models, allowing engineering and economic policy design problems to be addressed within the same framework. As a first step towards this integration, a methodology and case study for modeling the effects of an environmental tax policy on a P2P system is presented. Extensions of the existing framework to include partial, general and hybrid equilibrium models are also discussed.

Committee:

Bhavik Bakshi (Advisor); Liang-Shih Fan (Committee Member); James Rathman (Committee Member)

Subjects:

Chemical Engineering; Sustainability

Keywords:

Chemical engineering, process systems engineering, sustainability, process design, optimization, life cycle assessment

Slovenec, DerekSeismic Evaluation, Rehabilitation, and Improved Design of Sub-Standard Steel Concentrically Braced Frame Buildings
Master of Sciences (Engineering), Case Western Reserve University, 2016, Civil Engineering
Seismic design of multi-story buildings requires capacity design principles that allow for distributed damage (plastic member deformations) to occur over the building height while preventing soft-story failure mechanisms that may lead to collapse. Seismic evaluation of steel concentrically braced frame (CBF) buildings has revealed that they exhibit soft-story behavior due to non-uniform brace degradation and non-ductile failure modes. This research proposes a rehabilitative design procedure for existing buildings that uses a stiff rocking core to redistribute plastic deformations along the structure’s height. Additionally, an improved design procedure for braced frame columns is proposed for new frame design. Several representative frames were designed and evaluated using nonlinear transient seismic finite element analysis and large-scale hybrid experimental testing. Predicted, analytical, and experimental response results show reasonable agreement, and the proposed techniques are believed to be reliable for achieving desirable seismic performance in low- to mid-rise steel braced frame structures.

Committee:

Michael Pollino, Ph.D. (Advisor); Brian Metrovich, Ph.D. (Committee Member); YeongAe Heo, Ph.D. (Committee Member)

Subjects:

Civil Engineering

Keywords:

steel; braced frame; seismic rehabilitation; SRC; structural engineering; structural design; civil engineering; seismic; earthquake;

Taricska, MichaelAn Analysis of Recent Bridge Failures (2000-2012)
Master of Science, The Ohio State University, 2014, Civil Engineering
When discussing the infrastructure in America, and more specifically, the problems facing America's infrastructure, bridge failures have been one of the leading problems facing America's infrastructure. Bridge failures often are costly in the commerce foregone, lives lost, and replacement funds required to rebuild the failed bridge. More than 8,000 bridges are categorized as structurally deficient, and almost 25% of all bridges are categorized as functionally obsolete, resulting in a bridge rating of a C+ given by the American Society of Civil Engineers (ASCE) in 2013. Ongoing studies of following trends and patterns in bridge failures has been an important undertaking, which can greatly enhance the ability for engineers to predict and avoid the great costs associated with a bridge failure. Previous studies to compile and analyze bridge failure data were conducted over the timeframe of 1977 to 1981, 1981 to 1989, and 1989 to 2000. The aim of this study was to continue these studies by compiling a comprehensive database to display the findings of this study, both graphically and in tabular form. Finally, a model was needed in order to help the end user visualize and interpret the data in light of preventing future bridge failures; to that end, fuzzy logic was applied to the data in order to create a user-friendly and intuitive model for preventing future bridge failures. In all, it was also found that the most vulnerable sections in a bridge with regard to bridge failure were scouring and the bridge's age, resulting in unmaintained and crippling bridges.

Committee:

Fabian Tan (Advisor); Frank Croft (Committee Member); Halil Sezen (Committee Member)

Subjects:

Civil Engineering

Keywords:

Bridge Failure, Civil Engineering, Structural Engineering, Structural Failure, Collapse, Bridge Inpsection

Long, Leroy L.An Investigation into the Relationship between Technology and Academic Achievement among First-Year Engineering Students
Doctor of Philosophy, The Ohio State University, 2015, EDU Teaching and Learning
In order to increase the number of American STEM degree recipients, it is important for academics to develop ways to improve students’ interest, retention, and success in fields like engineering. The purpose of this study was to understand the relationship between first-year engineering students’ (FYES) perceived (a) knowledge, (b) usefulness, as well as (c) frequency and nature of use of technology and their academic achievement (i.e., grades). This investigation focused on the specific types and uses of educational technology by FYES, while also analyzing differences by race/ethnicity and gender. Previously, scholars have employed a broad definition of technology to describe hardware such as cell phones and computers or software for word processing and web-based applications. Such definitions have been used to understand how collegians, instructors, and professionals interact with technology. In the present study, educational technology signified specific computer and information technology such as computer hardware (e.g., desktops, laptops), computer software (e.g., Microsoft Word/Excel, MATLAB, SolidWorks), electronic devices (e.g., cellphones, tablets, E-readers), and the Internet (e.g., websites, course management systems). Rogers’ (1995) technology adoption theory was chosen for the current study as it related well to the present research questions. A multi-step approach (i.e., descriptive statistics, independent samples t-tests, hierarchical linear regression) was used to analyze survey data from nearly 500 students. Results from the present study determined there were significant racial/ethnic differences in FYES’ perceived usefulness as well as frequency and nature of use of technology. There were also significant gender differences in FYES’ perceived knowledge and usefulness of technology. Furthermore, FYES’ background characteristics significantly predicted their final course grades in the second of two Fundamentals of Engineering courses. Findings have important implications for practice, research, and theory surrounding FYES and educational technology.

Committee:

Paul Post, PhD (Advisor); Terrell Strayhorn, PhD (Advisor); Lin Ding, PhD (Committee Member); Robert Gustafson, PhD (Committee Member)

Subjects:

Education; Educational Technology; Engineering; Technology

Keywords:

Technology; Educational Technology; Technology Adoption; Academic Achievement; First-Year Students; First-Year Engineering Students; Underrepresented Students; Engineering Education;

Branlat, MatthieuChallenges to Adversarial Interplay Under High Uncertainty: Staged-World Study of a Cyber Security Event
Doctor of Philosophy, The Ohio State University, 2011, Industrial and Systems Engineering
The vulnerability of critical and valued digital infrastructures and the difficulty of defending networks against attacks are a growing concern throughout domains. While numerous efforts exist to improve cyber defense through technological advances, human-centered research to uncover and address the difficulties experienced by network defenders is recent and still limited. Moreover, understanding cyber security, a fundamentally adversarial domain, requires investigations of the interrelated defense and attack processes, but such studies are rare. The dissertation presents results from a staged-world study of an adversarial cyber security exercise. This daylong exercise involved forty participants divided into an outside attacking team and a defending team operating in a simulated production environment. The first objective is to identify critical skills and forms of expertise of cyber security as a domain of practice. Designed by cyber security experts, the exercise allowed for the investigation of core dimensions of cyber events, which have seen limited empirical study in past work on cyber defense: (1) decision-making in cyber defense; (2) network security within larger production structures and processes; (3) decision-making in cyber attack; and (4) interplay of attack and defense. The second objective of the research is to discuss the approach designed and implemented in order to capture and analyze the cyber event observed. Challenges result especially from the scale of the processes to be tracked (attack and defense; number of participants; distribution of participants in teams, roles and space; duration of the exercise). The study we conducted aimed at exploring the domain of cyber security with an emphasis on the methodological dimensions of such investigation. Given the partially novel character of the research, a critical account of choices made, successes and pitfalls experienced aims at informing future advancements in the domain. The third objective is to connect this study of the particular domain of cyber security to other studies of work in real-world situations. Relevant theoretical frameworks include: decision-making under uncertainty, distributed anomaly response, joint activity, perception of intent, and more generally Resilience Engineering. Making this link allows for the discussion of potential directions to improve cyber defense, as well as to further develop these theoretical frameworks. Cyber security, because of its nature and the typical challenges associated, constitutes a rich environment for such purposes.

Committee:

David D. Woods, PhD (Advisor); Philip J. Smith, PhD (Committee Member); Anish Arora, PhD (Committee Member)

Keywords:

cognitive systems engineering; resilience engineering; cyber security; adversarial event; staged-world study; decision-making; cyber defense; cyber attack; observational study

Grubb, Geoffrey FrancisImproving the Environmental Performance of Manufacturing Systems via Exergy, Techno-ecological Synergy, and Optimization
Doctor of Philosophy, The Ohio State University, 2010, Chemical Engineering

Increasing world population, dwindling resources, and the degradation of natural ecosystems make thermodynamic and environmental improvement of industrial processes a prominent goal for the engineering community for the foreseeable future. The present work contributes to this effort by exploring the application of life cycle assessment, first law energy analysis, and exergy analysis to emerging technologies. A process for producing titanium dioxide nanoparticles is investigated at both the local process and broader life cycle scales. This case study reveals that decisions made at one level of analysis are not always ideal when the boundaries are expanded to include the supply chain and environmental impacts. In addition, the insights gained from exergy analysis are not available from any other method of evaluation, suggesting that it should be broadly embraced as a process improvement tool.

Traditional engineering design is concerned with technological details and economics. Operating conditions and design alternatives are balanced with the bottom line. The second portion of this work shows how environmental considerations can be included in the design process in such a way that both the technological and ecological spheres can benefit. This is illustrated through two case studies pairing engineered systems with carbon sequestration available in natural systems. The first case study looks at the CGAM cogeneration plant from the industrial ecology literature. By simulating a hypothetical carbon network, allowing for sequestration through afforestation and underground geological storage, possible economic scenarios for complete or partial carbon mitigation for the power plant are explored. The second case study considers a biosolids network for the City of Columbus. Biosolids produced at two wastewater treatment plants in the City are allocated between four end-of-life alternatives: incineration, landfilling, composting, and land application as fertilizer. Most stages of the wastewater and biosolids treatment release greenhouse gases. A subnetwork of greenhouse gas mitigation techniques has been simulated using the EcoFlow software package. The overall system was optimized, and the results show significant improvements from the base case with respect to both the economic and environmental objectives. The effects of a carbon tax on the optimal solutions are also examined.

Committee:

Bhavik Bakshi, PhD (Committee Chair); Liang-Shih Fan, PhD (Committee Member); Michael Paulaitis, PhD (Committee Member)

Subjects:

Chemical Engineering; Energy; Environmental Engineering; Industrial Engineering; Systems Design

Keywords:

Process Systems Engineering; Process Design Optimization; Sustainable Engineering; Exergy; Industrial Ecology

Gopalakrishnan, VarshaNature in Engineering: Modeling Ecosystems as Unit Operations for Sustainability Assessment and Design
Doctor of Philosophy, The Ohio State University, 2017, Chemical Engineering
Sustainability assessment and design is a multidisciplinary problem that cannot be addressed by methods developed in a single discipline. Sustainability being anthropocentric has until now been addressed mostly by techno-centric methods that usually offer incremental improvements. This approach can guarantee solutions that continuously outperform previously obtained solutions while also minimizing environmental impact, but it disregards ecological thresholds or the limits imposed by nature. Consequently, designing and engineering systems that overshoot nature's capacity has been one of the primary causes for ecological degradation, contradictory to the goal of sustainable development. To avoid such unintended outcomes and perverse solutions, methods for sustainability must adopt a holistic approach towards assessment and design. Ecological systems that support the functioning of human activities by providing essential goods and services must be explicitly considered during the assessment and design phases. Explicitly including the role played by ecological systems in supporting human activities will enable accounting for the dependence and impact of technology on nature and vice versa, and enable systems to operate within ecological constraints. This dissertation contributes to the effort of including nature in engineering decisions for sustainability by developing assessment techniques, design methods and building inventories that will help in decision making. The Techno-Ecological Synergy (TES) framework developed earlier provides a basis for explicitly including the role played by nature in supporting human activities by quantifying the demand and supply of ecosystem services. Ecosystem service demand is quantified by emissions and resource used, while supply is quantified by the capacity of nature to provide services. While originally developed as a sustainability metric, this framework provided the initial motivation for exploring the feasibility of designing techno-ecological synergistic systems. Through several case studies, we show the economic and environmental benefits of such a system and identify several economic sectors and regions in the US where such techno-ecological synergistic systems can be designed. The second half of this dissertation focuses purely on the design of TES systems. The novel concept of designing ecosystems as unit operations is introduced and a design methodology for integrating technological and ecological systems is proposed. Novel process flow sheets that incorporate both these systems are designed and optimized to balance the ecosystem service demand with the supply subject to unit operation level constraints of technological and ecological systems. Ecosystem dynamics are accounted for by solving multi-period optimizations. We demonstrate the economic and environmental benefits of such a techno-ecological system by designing a biofuel production system with ecological systems like treatment wetlands and forest ecosystems. Finally, this dissertation also addresses another meta-principle for sustainability which is the consideration of a large systems boundary to prevent the shifting of impacts to different scales. A methodology for integrating the TES framework with the previously developed Process-to-Planet (P2P) multi-scale modeling framework is presented as a step towards simultaneously satisfying both the fundamental requirements for absolute sustainability. The methodology is applied to the design of a renewable energy production system and results illustrate the promise and benefits of such an approach.

Committee:

Bhavik Bakshi (Advisor); James Rathman (Committee Member); David Tomasko (Committee Member); Guy Ziv (Committee Member)

Subjects:

Chemical Engineering; Environmental Science; Sustainability

Keywords:

Chemical Engineering, Process Systems Engineering, Sustainability, Process Design, Ecosystem Services, Optimization

Ukidwe, Nandan UdayThermodynamic input-output analysis of economic and ecological systems for sustainable engineering
Doctor of Philosophy, The Ohio State University, 2005, Chemical Engineering
Traditional methods in engineering and economics focus on economic capital while ignoring the natural capital, leading to environmentally unconscious and unsustainable industrial operations. This dissertation proposes a new thermodynamic approach to address this shortcoming. The new approach, called Thermodynamic Input-Output Analysis (TIOA), calculates degradation of energy quality in the economic and ecological stages of a process’ or product’s supply network. The energy quality is measured in terms of exergy or available energy. TIOA synthesizes natural and human resource and emission data from various public domain databases. It uses concepts from systems ecology to determine exergy flows in the ecological stages and economic input-output analysis to determine exergy flows in the economic stages of a supply network. This dissertation applies TIOA to analyze 91-sector 1992 and 488-sector 1997 representations of the US economy. It calculates natural capital throughputs of individual industry sectors in terms of their Ecological Cumulative Exergy Consumption (ECEC). It also juxtaposes natural capital throughputs with economic capital throughputs by calculating ECEC/money ratios. These ratios indicate the discrepancy between thermodynamic work and the willingness of people to pay for economic goods and services. ECEC/money ratios are found to decrease from basic infrastructure industries to value-added service industries suggesting that the service industries are better at valuing ecosystem contribution than resource extraction and manufacturing industries. These results have important implications to designing sustainable macroeconomic policies. The industry-specific ECEC/money and ICEC/money ratios are a major improvement over single economy-wide emergy/$ ratio in emergy analysis and similar aggregate metrics in thermoeconomics. Such industry specific ratios are useful in hybrid thermodynamic analysis of industrial systems and provide a unique insight into their environmental implications. This has been illustrated by comparing alternative electricity generation systems. Industry specific ECEC/money and ICEC/money ratios are also useful in constructing hierarchical thermodynamic metrics of sustainability. Such metrics are stackable, robust, and communicable to diverse stake-holders. In the end, this dissertation proposes a multiscale statistical data fusion framework for Life Cycle Inventory analysis. Such framework ensures maximum utilization of available data and models, and can identify missing data, reconcile conflicting data and determine confidence bounds on LCA results by incorporating stochastic and subjective knowledge.

Committee:

Bhavik Bakshi (Advisor)

Keywords:

Process Systems Engineering; Industrial Ecology; Environmental Life Cycle Assessment and Sustainable Engineering

Tsakalakis, MichailDesign of A Novel Low – Cost, Portable, 3D Ultrasound System with Extended Imaging Capabilities For Point-of-Care Applications
Doctor of Philosophy (PhD), Wright State University, 2015, Computer Science and Engineering PhD
Ultrasound Imaging (USI) or Medical Sonography (MS), as it is formally called, has been widely used in biomedical applications over the last decades. USI can provide clinicians with a thorough view of the internal parts of the human body, making use of sound waves of higher frequencies than humans can perceive. USI systems are considered highly portable and of low–cost, compared to other imaging modalities. However, despite those advantages, Ultrasound Systems (US) and especially 3D ones, have not been yet extensively utilized for Point-of-Care (POC) applications, due to numerous restrictions and artifacts that they currently present. Hardware complexity and real-time requirements are considered to be the major restrictions for portable, 3D (volumetric) USI. Volumetric transducers consist of thousands of piezoelectric elements that make the signaling and the networking of the system extremely complex. Additionally, regions of the internal body require significantly long time to be scanned in the three dimensions. Consequently, real-time applications are considered prohibited. Last, but yet equivalently important, most of the low-cost, portable systems manifest artifacts that degrade the quality of ultrasound image. It is obvious that researchers’ concern and major challenge is to successfully address those problems and manage offset the strong trade-offs that exist. Given the aforementioned challenge, the current research work presents a novel low–cost, portable 3D Ultrasound system design, composed of four volumetric transducers. The system has been designed for POC applications in a way to manifest extended imaging capabilities. The use of multiple (four), simple 2D phased array transducers is adopted in order for the system to provide enhanced field of view, as well as automatic scanning of the Region of Interest (ROI) (radiologist intervention-free). In order to deal with the high complexity of the system, the transducers were designed with limited number of elements (256 each) and were integrated to a single FPGA board. To compensate for the image degradation caused by transducers of fewer elements, a new image enhancement methodology was proposed. The methodology targets to image de–speckling and image resolution improvement, given the redundant information provided by the multiple transducers. It uses a combination of spatial and frequency compounding techniques along with a Super-Resolution (SR) algorithm. In order to vindicate the selection of the techniques that were used for the proposed methodology, a parametric study regarding the performance of numerous de-noising and SR techniques was conducted. The performance of the methodology was firstly tested using typical 1D phased array transducers and the results in the 2D images offered promising insights its advantages. Having verified the effectiveness of the proposed methodology for the case of 2D ultrasound images, the methodology was extended to volumetric images. The final de-noised B-mode images manifested increased Contrast Noise Ratio (CNR) and Signal to Noise Ratio (SNR) compared to various other ultrasound image de-speckling techniques, while at the same time image resolution improvement was observed. The novel low–cost, portable 3D Ultrasound system design that is proposed, combined with the new image enhancement technique implemented, successfully addresses the existing challenges, in regards to the trade-off between system complexity and image quality. In fact, it not only develops a system of significantly lower complexity but the same time tackles the disadvantages that such a system could have, by integrating in the design the component of image enhancement.

Committee:

Nikolaos Bourbakis, Ph.D. (Advisor); Soon M. Chung, Ph.D. (Committee Member); Yong Pei, Ph.D. (Committee Member); Konstantina Nikita, Ph.D. (Committee Member); Catherine Marco, Ph.D. (Committee Member)

Subjects:

Biomedical Engineering; Computer Engineering; Computer Science

Keywords:

computer engineering;computer science;biomedical engineering

Yacinthe, SamuelSystem Safety Development of a Performance PHEV Through a Model-Based Systems Engineering Approach
Master of Science, The Ohio State University, 2016, Mechanical Engineering
The Ohio State University is participating in EcoCAR 3, which is a four-year long competition amongst 16 North American university teams to redesign the 2016 Chevrolet Camaro to reduce its environmental impact, while maintaining the muscle and performance expected from the iconic American car. To effectively assess and increase overall product quality and readiness of Ohio State’s vehicle, this work defines and deploys a state of the art Model-Based Systems Engineering (MBSE) approach for managing engineering complexity as it relates to requirements management, traceability, and fulfillment. To demonstrate the effectiveness of the implemented approach, this work presents system safety development activities that have been conducted during the first two years of the competition. As EcoCAR 3 transitions into year-three, this work has already contributed to over a dozen awards by increasing overall documentation, traceability and workflow management as part of the overall engineering development process.

Committee:

Shawm Midlam-Mohler (Advisor); Giorgio Rizzoni (Committee Member)

Subjects:

Automotive Engineering; Mechanical Engineering

Keywords:

Model-Based Systems Engineering, Automotive, Mechanical Engineering

Buettner, Robert W.Dynamic Modeling and Simulation of a Variable Cycle Turbofan Engine with Controls
Master of Science in Mechanical Engineering (MSME), Wright State University, 2017, Mechanical Engineering
Next generation aircraft (especially combat aircraft) will include more technology and capability than ever before. This increase in technology comes at the price of higher electrical power requirements and increased waste heat that must be removed from components to avoid overheating induced shutdowns. To help combat the resulting power and thermal management problem, a vehicle level power and thermal management design and optimization toolset was developed in MATLAB®/Simulink®. A dynamic model of a three-stream variable cycle engine was desired to add to the capabilities of the power and thermal management toolset. As an intermediate step to this goal, the dynamic mixed-flow turbofan engine model previously developed for the toolset was modified with an afterburner, a variable geometry nozzle, and a new controller to automatically control the new components. The new afterburning turbofan engine model was tested for a notional mission profile both with and without power take-off. This testing showed that the afterburning turbofan engine model and controller were successful enough to justify moving on to the development of the three-stream variable cycle engine model. The variable cycle engine model was developed using the components of the afterburning turbofan model. The compressor and turbine components were modified to use maps that incorporate the effects of variable inlet guide vane angles. The new engine model and components were sized by attempting to match data from a Numerical Propulsion System Simulation model with similar architecture. A previously developed heat exchanger model was added to the third stream duct of the new engine model. Finally, a new simplified controller was developed for the variable cycle engine model based on the controller developed for the afterburning turbofan model. The new variable cycle engine model was tested for a notional mission profile for five cases. The first case operated the engine model without power take-off and with the third stream heat exchanger removed. The second case added shaft power take-off. The third and fourth cases did away with the power take-off and added the heat exchanger to the engine model with two different hot-side mass flow rate conditions. The fifth case tested the engine with both power take-off and the third stream heat exchanger. The results were promising, showing that the variable cycle engine model had variable cycle tendencies even with a minimum of controlled variable geometry features. The controller was found to be effective, though in need of upgrades to take advantage of the benefits offered by a variable cycle engine. Additionally, it was found that both power take-off and heat rejection to the third stream impact the entire engine cycle.

Committee:

Rory Roberts, Ph.D. (Advisor); Mitch Wolff, Ph.D. (Committee Member); Rolf Sondergaard, Ph.D. (Committee Member); Robert Fyffe, Ph.D. (Other)

Subjects:

Aerospace Engineering; Mechanical Engineering

Keywords:

mechanical engineering; aerospace engineering

Case, Sarah SInstantaneous Kinematic Analyses of Spur and Helical Gear Pairs Having Runout and Wobble Errors
Master of Science, The Ohio State University, 2018, Mechanical Engineering
In this study, a two-dimensional model is proposed for determining theoretical contact lines, tooth separation, and approximated loaded transmission error with frequency spectra thereof, as well as various other output variables such as instantaneous center distance, operating pressure angle, and instantaneous contact ratio when circular runout error is applied to either or both gears in a spur or helical gear pair. As an addendum, a method for calculating off-line of action tooth separation using this model is described for spur gears. Additionally, a three-dimensional model is proposed for determining theoretical contact lines and tooth separation when any combination of circular runout or wobble error are applied to either or both gears in a spur or helical gear pair. Sample analyses are shown for spur and helical gear pairs with runout error applied using the two-dimensional model, and a helical gear pair with various combinations of runout and wobble error applied using the three-dimensional model. The results are discussed qualitatively with respect to the expected effects the applied errors would have on the tooth separation and related variables.

Committee:

David Talbot (Advisor); Ahmet Kahraman (Committee Member)

Subjects:

Mechanical Engineering

Keywords:

gears; spur gears; helical gears; gear runout; circular runout; gear wobble; gear manufacturing error; kinematic gear analysis; instantaneous gear analysis; gear eccentricity; mechanical engineering; engineering

Altalebi, Hasanain BasimProcessing of Ultra-Thin Film of Un Modified C60 Fullerene Using the Langmuir-Blodgett Technique. Effect of Structure on Stiffness and Optoelectric Properties
Master of Science in Materials Science and Engineering (MSMSE), Wright State University, 2017, Materials Science and Engineering
Monolayer films of C60 fullerene were for the first time produced successfully by using the Langmuir-Blodgett technique. The processing parameters were optimized and the structure of these films has been investigated using Scanning Tunneling Microscopy (STM) and Atomic Force Microscopy (AFM). Film stiffness was measured to be in the range of 15 MPa to 32 MPa depending on the nature of the solvent used to process the films. Optical transparency and electrical performance have been measured and correlated to the film structure. While 100% transparent, the film measured conductivity was in the range of 1013 S/m, that is orders of magnitude higher than silver, copper, and even compacted graphene sheets. These films have great potential applications in many different fields including transparent electrodes, sensor, optoelectronic devices and photovoltaics.

Committee:

Maher Amer, Ph.D. (Committee Chair); Ahsan Mian, Ph.D. (Committee Member); Allen Jackson, Ph.D. (Committee Member)

Subjects:

Engineering; Materials Science

Keywords:

Ultra; Thin Film; Un modified; Fullerene; Langmuir-Blodgett Technique; Optoelectric; Engineering; Materials Engineering

Shoger, Suzanne GrasselEngaging the Gatekeepers: Empowering Male Collegians to Promote Gender Equity in Engineering
Doctor of Philosophy, The Ohio State University, 2018, Educational Studies
Improving collegiate women’s access to and retention in engineering requires a multifaceted approach. Though a majority of existing interventions are aimed at changing women, strengthening their skills, and increasing their networks, little emphasis is directed at addressing the institutional factors that influence women’s opportunities for advancement (Cook & Glass, 2014; Ely, Ibarra, & Kolb, 2011). From a social justice perspective, research has demonstrated that allies, those from the dominant social group who understand the inequity placed on those in the minority, can be critical in addressing climate issues and promoting inclusivity (Harris & Edwards, 2010; Munin & Speight, 2010). Allies in Engineering (AIE) was created as a cohort of twelve male undergraduate and graduate engineering students who engaged in a co-curricular social justice education program over a period of one academic year designed to promote gender equity in an Engineering College (EC). Rather than situate responsibility for change solely with women (Lynch & Nowosenetz, 2009; Schafer, 2006), AIE was developed as a means of harnessing majority support, in this case males, as advocates for equity. While participating in social justice education focused on topics such as gender inequality, implicit bias, microaggressions, and systems of oppression, AIE cohort members were equipped to act as advocates and allies specifically for women in the EC, but also for other underrepresented groups. Through programming and outreach, this cohort also educated other EC community members, particularly men, on the importance of gender and other forms of equity. The methodological approach guiding this research was case study. The AIE cohort, inclusive of program sponsors (faculty and administrators) and archival materials, formed the unit of analysis, providing a structure for the collection and evaluation of data in this study. Analysis of AIE alumni focus group data, program sponsor interview data, and archival materials encompassed narratives of the collective and were examined through the lens of Weick’s (1995) seven elements of sensemaking to better understand the overall impact of the AIE program on participants. The focus of this study was to understand how the male cohort members as well as the sponsors of the program made sense of the initiative and of their roles as advocates and allies for gender equity in the EC. What emerged from this study was both larger and smaller than the capacity of one engineering college to effect change. The worldviews of several cohort members were reported to have been altered as a result of AIE. These students are now taking expanded views of inclusive environments and practices into their workplaces and into their adult lives, the impact of which will not be fully known for quite some time, if ever. Conversely, the majority of participants in this study, both students and program sponsors, agreed that the AIE initiative likely did not impact the climate of the EC in significant ways. While the program sponsors worked to make sense of the initiative, their basic views remained the same from the start of the program until the time of this study.

Committee:

Tatiana Suspitsyna (Advisor); Matthew Mayhew (Committee Member); Collette Dollarhide (Committee Member)

Subjects:

Education; Educational Leadership; Engineering; Gender; Gender Studies; Higher Education; Higher Education Administration; Womens Studies

Keywords:

Gender equity; gender; engineering education; allies; diversity; higher education; sensemaking; women in engineering

Sridhar, NigamanthDynamically reconfigurable parameterized components
Doctor of Philosophy, The Ohio State University, 2004, Computer and Information Science
With the size and complexity of software systems growing at a very fast pace, one of the concerns that we have to address is that of tractable reasoning. We need to make sure that the software we build does not exceed the limits of our understanding. Since we only know how to reason about software of limited sizes, we need to find a way of always keeping the logical size of the programs we write small. Software should thus be built from small, well-understood components put together in predictable ways. Parameterization is a technique that can greatly help in building scalable, flexible, and robust software systems. An important consideration with parameterized components is the time of binding parameters to the component; whether a commitment to parameters can be changed or not depends on the binding time. In order to achieve maximum flexibility, parameters should be bound as late as possible. Postponing parameter binding to execution time allows for the selection of parameters to be most effective, because it is at run time that details of a system are most complete. Further, dynamically bound parameterized components also present the possibility for dynamic reconfiguration. In this dissertation, we present a methodology for building dynamically reconfigurable parameterized components. The methodology is presented as a design pattern, with minimal assumptions on the target programming language or environment. The Service Facility design pattern offers a model of parameterized components that supports dynamic binding of parameters. Further, the model supports a mode of dynamic reconfiguration called dynamic module replacement, which involves re-binding of some or all of the parameters to a parameterized component during run time. The model also includes safety conditions to ensure that the dynamic parameter bindings (and re-bindings) are correct with respect to type-safety. The techniques and ideas presented in this dissertation are in the context of wellknown and widely-used technologies (such as Java, .NET, and XML) so as to enable these ideas to be inducted into practice quickly. The solutions presented here are generic and incrementally deployable.

Committee:

Paolo Sivilotti (Advisor)

Subjects:

Computer Science

Keywords:

Software engineering; Component-based software engineering; Component-oriented programming; Reusable software; Object-oriented programming; Design patterns

Urban, Robert AnthonyToward Sustainability through Techno-Ecological Synergy: Including Ecosystems in Engineering Design and Analysis
Doctor of Philosophy, The Ohio State University, 2012, Chemical and Biomolecular Engineering

For any human-designed system to be sustainable, ecosystem services that support it must be readily available. This work explicitly accounts for this dependence by designing synergies between technological and ecological systems. The resulting techno-ecological synergy mimics nature at the systems level, can stay within ecological constraints, and can identify novel designs that are economically and environmentally attractive and may not be found by the traditional design focus on technological options. This approach is outlined from a general engineering perspective using several qualitative examples as well as through presenting general heuristics and potential applications, and then showcased by designing synergies for a typical American suburban home. Systems included in the design optimization include typical ecosystems in suburban yards: lawn, trees, water reservoirs, and a vegetable garden; technological systems: heating, air conditioning, faucets, solar panels, etc.; and behavioral variables: heating and cooling set points. The ecological and behavioral design variables are found to have a significant effect on the three objectives, in some cases rivaling and exceeding the effect of traditional technological options. These results indicate the importance and benefits of explicitly including ecosystems in the design of sustainable systems, something that is rarely done in existing methods. In addition to process design, the concept of techno-ecological synergy is applied to supply chain design, which is illustrated through two case studies: the optimization of the US transportation fuel portfolio, and a land use decision problem. Both cases studies illustrate how including ecosystem services can be done in supply chain management. These problems can be extended to more complex systems through the use of the presented input-output methodology.

The second part of this work deals with the analysis of integrated techno-ecological systems. First, the ecologically-based life cycle assessment (Eco-LCA) method is applied to compare the production of 1,3-propanediol (PDO) from fossil and biomass feedstocks. In addition to giving a general overview of the Eco-LCA method, this study indicates that bio-based PDO is superior to fossil-based PDO in terms of emissions, energy, and non-renewable resource consumption, but has a much higher reliance on ecological systems and stresses water emissions such as nitrogen and phosphorous more. Next, the systems ecology method of emergy analysis is applied to the production of LIHD ethanol and the results are compared to other fuels. Based on the emergy metrics calculated, LIHD ethanol is superior to many other fuels in terms of sustainability, but has a low return on investment relative to fossil fuels. Finally, a novel method for including spatial ecological data models in life cycle assessment is presented, and the resulting spatially hybrid LCA is applied to a case study that compares biofuels produced from corn and cellulosic biomass. The results show that accounting for locally specific ecological systems gives insight into both the spatial and indirect life cycle effects of a process. Based on the ecosystem services considered (carbon sequestration, nutrient retention, and soil erosion), ethanol produced from low input, high diversity grass (LIHD) is inferior to that produced from corn on a per-liter of ethanol basis.

Committee:

Bhavik Bakshi (Advisor); Jay Martin (Committee Member); James Rathman (Committee Member); Barbara Wyslouzil (Committee Member)

Subjects:

Alternative Energy; Chemical Engineering; Ecology; Sustainability; Systems Science

Keywords:

process systems engineering;sustainability;chemical engineering;ecological modeling;optimization;life cycle assessment

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