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- Title
- A computerized digital data acquisition system for electrochemical experiments
- Creator
- Cardarelli, Joseph Samuel, 1944-
- Date
- 1971
- Collection
- Electronic Theses & Dissertations
- Title
- A-stable implicit rapid scheme and software solution for electromagnetic wave propagation
- Creator
- Thavappiragsam, Mathialakan
- Date
- 2019
- Collection
- Electronic Theses & Dissertations
- Description
-
"A robust and rapid scheme to solve electromagnetics (EM) is an important requirement in the scientific computing environment in which there are several useful methods used to solve tasks in EM. Our research study is motivated by this need and is targeted to develop a fast A-stable implicit numerical scheme and scalable software solution for EM wave propagation. Our scheme is based on the Method Of Lines Transpose (MOLT) approach which discretizes time first and then solves boundary value...
Show more"A robust and rapid scheme to solve electromagnetics (EM) is an important requirement in the scientific computing environment in which there are several useful methods used to solve tasks in EM. Our research study is motivated by this need and is targeted to develop a fast A-stable implicit numerical scheme and scalable software solution for EM wave propagation. Our scheme is based on the Method Of Lines Transpose (MOLT) approach which discretizes time first and then solves boundary value problems. By applying the free-space Green's function, the solution is derived by decomposing particular and homogeneous solutions. The compact Simpson's quadrature based, O(N) fast convolution, a recursive algorithm, is used to solve the particular solution for N number of grid points. The homogeneous solution is obtained using a particular solution at the boundary points and the applied boundary conditions. The multi-dimensional scheme is developed using the ADI splitting approach and an arbitrary order accuracy in time is achieved by switching the time derivation to a spatial derivation using the Lax-Wendroff approach.The focus of the work in this thesis has been to overcome the limitations in Neumann and outflow boundary conditions to get high-order accuracy by using special treatments that deal with a choice of the interpolation, finite difference stencil, and the initial conditions. In addition, we have extended these ideas to construct perfectly electrically conducting boundary conditions in 2D for the MOLT.In addition to introducing higher-order boundary conditions, an embedded boundary method is employed to deal with complex geometries. As the method is A-stable, it does not suffer from small-time step limitations that are found in explicit finite difference time domain methods when using either embedded boundary or cut cell methods to capture geometry. Further, we are developing an open source code MOLTN (Method Of Lines Transpose, Nth order) which is intended to be a hardware-independent, scalable software tool, using multi-node MPI, multi-core OpenMP, and GPU CUDA implementation. As a test case of the method, we implement and study the A6 magnetron with our embedded boundary method using point sources inside of the domain. The eventual goal is to combine this method with a novel particle method for the simulations of plasma. The particle method would treat particles as point particles that generate fields that are tracked on the mesh. No density or current will be mapped to the mesh. The consistency and performance of the scheme are evaluated for EM wave propagation and scattering using different shaped objects including curved boundaries and the introduction of true point sources that demonstrate how we handle particles. Stable solutions result for a wide range of mesh sizes and potential to leverage novel computing architectures, such as GPU, have been demonstrated."--Pages ii-iii.
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- Title
- Attribute prediction from near infrared iris and ocular images
- Creator
- Bobeldyk, Denton
- Date
- 2019
- Collection
- Electronic Theses & Dissertations
- Description
-
The iris is the colored portion of the eye surrounding the pupil. Images captured in the visible spectrum make it difficult for the rich texture of brown irides to be discerned; therefore, iris recognition systems typically capture an image in the Near Infrared (NIR) spectrum. The region surrounding the iris, the ocular region, is also captured by the sensor during the imaging process.The focus of this thesis is on developing methods for predicting soft biometric attributes of an individual...
Show moreThe iris is the colored portion of the eye surrounding the pupil. Images captured in the visible spectrum make it difficult for the rich texture of brown irides to be discerned; therefore, iris recognition systems typically capture an image in the Near Infrared (NIR) spectrum. The region surrounding the iris, the ocular region, is also captured by the sensor during the imaging process.The focus of this thesis is on developing methods for predicting soft biometric attributes of an individual based on the iris and ocular components of the eye. In addition to attribute prediction, the effect of covariates on attribute prediction are also studied. Attributes considered in this work include gender, race and eye color. For the gender and race attributes, both the iris and surrounding ocular region are analyzed to determine which region provides the greatest gender cues. A regional analysis reveals that the iris-excluded ocular region provides a greater gender prediction accuracy than the iris-only region. This finding is of great significance as, typically, the iris-excluded ocular region is discarded by the iris recognition system. This research reinforces the need to retain the iris-excluded ocular region for additional processing. For race, it is shown that the iris-only region provides better prediction accuracy. In order to study the stability of the gender and race features, the impact of image blur on attribute prediction was also examined. It is observed that as the level of image blur increases, the race prediction accuracy decays at a much faster rate than that of gender. For eye color, the textual cues presented on the iris stroma are exploited to generate a discriminatory feature vector that is capable of distinguishing between two categories of eye color. The impact of image resolution on attribute prediction was also determined. A convolutional neural network architecture is presented that is capable of attribute prediction using images as small as 5x6, a mere 30 pixels. Experimental results suggest the possibility of deducing soft biometric attributes from low resolution images, thereby underscoring the feasibility of extracting these attributes from poor quality images. Finally, the thesis explores the possibility of harnessing the feature vector used to predict one attribute (e.g., gender) in order to predict a different attribute (e.g. race). The ensuing experiments convey the viability of cross attribute prediction in the context of NIR ocular images.In summary, this thesis provides insight into attribute prediction from NIR ocular images by conducting an extensive set of experiments.
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- Title
- Automated revision of distributed and real-time programs
- Creator
- Bonakdarpour, Borzoo
- Date
- 2009
- Collection
- Electronic Theses & Dissertations
- Title
- Automatic verification and revision of multitolerant programs
- Creator
- Chen, Jingshu
- Date
- 2013
- Collection
- Electronic Theses & Dissertations
- Description
-
The notion of multitolerance is based on the observation that modern programs are often subject to multiple faults. And, the requirements in the presence of these faults vary based on the nature of the faults, its severity and the cost of providing fault-tolerance to it. Also, assurance of multitolerant systems is necessary via they are integral parts of our lives. This dissertation proposes to provide such assurance via automated verification and revision.Regarding verification, we focus on...
Show moreThe notion of multitolerance is based on the observation that modern programs are often subject to multiple faults. And, the requirements in the presence of these faults vary based on the nature of the faults, its severity and the cost of providing fault-tolerance to it. Also, assurance of multitolerant systems is necessary via they are integral parts of our lives. This dissertation proposes to provide such assurance via automated verification and revision.Regarding verification, we focus on verification of self-stabilization, which is the ability of the program to recover from arbitrary states. We consider verification of self-stabilization because several multitolerant systems are indeed stabilizing. Also, most of literature on verification of fault-tolerance focuses on safety property; our work complements it by considering liveness properties. Hence, we envision verification of multitolerant programs by using existing approaches for verifying safety and using the results from this dissertation for verifying liveness. We propose a technique that is based on a bottleneck (fairness requirements) identified in existing work on verification of stabilization. Our approach uses the role of fairness along with symbolic model checking, and hence reduces the cost of verification substantially. We also propose a constraint-based approach that reduces the task of verifying self-stabilization into a well-studied problem of constraint solving, so that one can leverage the use of existing highly optimized solutions (SAT/SMT solvers) to reduce the verification cost.Regarding revision, we focus on revising existing programs to obtain the corresponding multitolerant ones. Revising the program manually is expensive since it requires additional verification steps to guarantee correctness. Also, manual revision may violate existing requirements. For these reasons, we propose an automatic approach to revise a given program to add multitolerance to the given class(es) of faults. Specifically, we characterize multitolerance in terms of strong multitolerance and weak multitolerance. Intuitively, strong multitolerance provides higher guarantees than weak multitolerance. However, there are scenarios where designing a strong multitolerant program is expensive or impossible although designing weak multitolerance is feasible. We investigate the complexity of automatic revision for adding multitolerance. In particular, we identify instances where adding weak multitolerance is NP-hard even though adding strong multitolerance in the same setting in P. We also develop algorithms (and heuristics) for automatic revision for adding multitolerance to existing programs. We implement these algorithms in a model repair tool for automatically adding multitolerance. Additionally, we build a lightweight framework that utilizes our model repair tool for automatically revising UML state diagram for adding fault-tolerance. This framework has several practical and methodological significance regarding the development of concurrent software. Specifically, this framework allows designers to revise an existing UML model to add fault-tolerance without a detailed knowledge of the formalism behind model repair algorithms.
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- Title
- Candidate evaluation : a task specific architecture using multi-attribute utility theory with applications in international marketing
- Creator
- Mitri, Michel
- Date
- 1992
- Collection
- Electronic Theses & Dissertations
- Title
- Computer assisted investigations
- Creator
- Palmatier, David C.
- Date
- 1997
- Collection
- Electronic Theses & Dissertations
- Title
- Framework for incorporating rutting prediction model in the reliability-based design of flexible pavements
- Creator
- Kim, Hyung Bae
- Date
- 1999
- Collection
- Electronic Theses & Dissertations
- Title
- Integrating informal and formal approaches to object-oriented analysis and design
- Creator
- Wang, Yile Enoch
- Date
- 1998
- Collection
- Electronic Theses & Dissertations
- Title
- Integrative analysis of state-based requirements for completeness and consistency
- Creator
- Czerny, Barbara Jean
- Date
- 1998
- Collection
- Electronic Theses & Dissertations
- Title
- Investigating the true return on investment : a descriptive analysis of public relations agency-client relationships using the Relqual scale
- Creator
- Everling, Kelly B.
- Date
- 2009
- Collection
- Electronic Theses & Dissertations
- Title
- Precise methods for pre-calculation of cyclotron control settings
- Creator
- Berg, Richard Eugene
- Date
- 1966
- Collection
- Electronic Theses & Dissertations
- Title
- Teaching and learning with digital evolution : factors influencing implementation and student outcomes
- Creator
- Lark, Amy M.
- Date
- 2014
- Collection
- Electronic Theses & Dissertations
- Description
-
Science literacy for all Americans has been the rallying cry of science education in the United States for decades. Regardless, Americans continue to fall short when it comes to keeping pace with other developed nations on international science education assessments. To combat this problem, recent national reforms have reinvigorated the discussion of what and how we should teach science, advocating for the integration of disciplinary core ideas, crosscutting concepts, and science practices....
Show moreScience literacy for all Americans has been the rallying cry of science education in the United States for decades. Regardless, Americans continue to fall short when it comes to keeping pace with other developed nations on international science education assessments. To combat this problem, recent national reforms have reinvigorated the discussion of what and how we should teach science, advocating for the integration of disciplinary core ideas, crosscutting concepts, and science practices. In the biological sciences, teaching the core idea of evolution in ways consistent with reforms is fraught with challenges. Not only is it difficult to observe biological evolution in action, it is nearly impossible to engage students in authentic science practices in the context of evolution. One way to overcome these challenges is through the use of evolving populations of digital organisms.Avida-ED is digital evolution software for education that allows for the integration of science practice and content related to evolution. The purpose of this study was to investigate the effects of Avida-ED on teaching and learning evolution and the nature of science. To accomplish this I conducted a nationwide, multiple-case study, documenting how instructors at various institutions were using Avida-ED in their classrooms, factors influencing implementation decisions, and effects on student outcomes. I found that all of the participating instructors held views on teaching and learning that were well aligned with reform-based pedagogy, and although instructors used Avida-ED in a variety of ways, all adopted learner-centered pedagogical strategies that focused on the use of inquiry. After implementation, all of the instructors indicated that Avida-ED had allowed them to teach evolution and the nature of science in ways consistent with their personal teaching philosophies. In terms of assessment outcomes, students in lower-division courses significantly improved both their understanding and acceptance of evolution after using Avida-ED, and learning of content was positively associated with increased acceptance. Although student learning outcomes and instructor familiarity with Avida-ED were not associated with student affective response to the program, instructor familiarity was highly influential with regard to both how Avida-ED was implemented and student affective response, particularly student interest, enjoyment, and self-efficacy. The results of this dissertation provide strong evidence suggesting that Avida-ED is a promising tool for teaching and learning about evolution in reform-based ways, and suggest that improving instructor pedagogical content knowledge with regard to research-based tools like Avida-ED may be implicated in generating student interest in STEM.
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- Title
- The purposes and audiences of software writing in large-scale technical projects
- Creator
- Fry, Robert Bruce
- Date
- 1986
- Collection
- Electronic Theses & Dissertations
- Title
- The use and value of a computer self-assessment program as perceived by Michigan field-based extension educators
- Creator
- Cui, Guilin
- Date
- 1996
- Collection
- Electronic Theses & Dissertations