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Title: Vision-based tracking of fiducials for augmented reality
Creator: Middlin, Paul W.
Date: 2002
Collection: Electronic Theses & Dissertations

Title: Validation of two growth and yield models on red pine plantations in Michigan
Creator: Smith-Mateja, Erin E.
Date: 2003
Collection: Electronic Theses & Dissertations

Title: Using top down multiport modeling for automotive applications
Creator: Minor, Mark Andrew
Date: 1996
Collection: Electronic Theses & Dissertations

Title: Using computer simulations to study relativistic heavy ion collisions
Creator: Murray, Joelle
Date: 1998
Collection: Electronic Theses & Dissertations

Title: Unconstrained 3D face reconstruction from photo collections
Creator: Roth, Joseph (Software engineer)
Date: 2016
Collection: Electronic Theses & Dissertations
Description: This thesis presents a novel approach for 3D face reconstruction from unconstrained photo collections. An unconstrained photo collection is a set of face images captured under an unknown and diverse variation of poses, expressions, and illuminations. The output of the proposed algorithm is a true 3D face surface model represented as a watertight triangulated surface with albedo data colloquially referred to as texture information. Reconstructing a 3D understanding of a face based on 2D input...
Show moreThis thesis presents a novel approach for 3D face reconstruction from unconstrained photo collections. An unconstrained photo collection is a set of face images captured under an unknown and diverse variation of poses, expressions, and illuminations. The output of the proposed algorithm is a true 3D face surface model represented as a watertight triangulated surface with albedo data colloquially referred to as texture information. Reconstructing a 3D understanding of a face based on 2D input is a long-standing computer vision problem. Traditional photometric stereo-based reconstruction techniques work on aligned 2D images and produce a 2.5D depth map reconstruction. We extend face reconstruction to work with a true 3D model, allowing us to enjoy the benefits of using images from all poses, up to and including profiles. To use a 3D model, we propose a novel normal field-based Laplace editing technique which allows us to deform a triangulated mesh to match the observed surface normals. Unlike prior work that require large photo collections, we formulate an approach to adapt to photo collections with few images of potentially poor quality. We achieve this through incorporating prior knowledge about face shape by fitting a 3D Morphable Model to form a personalized template before using a novel analysis-by-synthesis photometric stereo formulation to complete the fine face details. A structural similarity-based quality measure allows evaluation in the absence of ground truth 3D scans. Superior large-scale experimental results are reported on Internet, synthetic, and personal photo collections.
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Title: Two-dimensional drafting template and three-dimensional computer model representing the average adult male in automotive seated postures
Creator: Bush, Neil James
Date: 1992
Collection: Electronic Theses & Dissertations

Title: Toward a formalization of demographic transition theory
Creator: Lazer, S. Charles, 1946-
Date: 1969
Collection: Electronic Theses & Dissertations

Title: Three-dimensional dynamic motion of the shoulder complex
Creator: Reid, Tamara Ann
Date: 1994
Collection: Electronic Theses & Dissertations

Title: The quest for active media models : a self-consistent framework for simulating wave propagation in nonlinear systems
Creator: Glosser, Connor Adrian
Date: 2018
Collection: Electronic Theses & Dissertations
Description: This work presents new approaches to simulations of active media at the level of individual particles. Active systems contain internal, nonlinear, processes beyond those of simple scattering systems; thus these new models afford high degrees of fidelity in exploring the underlying physics without recourse to continuum or spatially-averaged approximations.First, I examine the dynamics of microspheres set into motion by ambient acoustic radiation in a fluid described by potential flow in the...
Show moreThis work presents new approaches to simulations of active media at the level of individual particles. Active systems contain internal, nonlinear, processes beyond those of simple scattering systems; thus these new models afford high degrees of fidelity in exploring the underlying physics without recourse to continuum or spatially-averaged approximations.First, I examine the dynamics of microspheres set into motion by ambient acoustic radiation in a fluid described by potential flow in the long-wavelength limit. Variations in the local surface pressure caused by scattering from each microsphere set each microsphere into motion following Newton’s second law. By expanding this pressure in terms of spherical harmonics—natural eigenfunctions of the unretarded radiation kernel—I recover an analytic description of the force on individual microspheres due to an incident waveform. High-order numerical integrations then relate the surface potential on one microsphere to the surface pressure on the others, thereby coupling the microspheres’ trajectories. These simulations predict a dominant translational effect along the direction of propagation of the incident waveform, though they also reveal significant dipolar interactions between microspheres that produce secondary expansions and contractions of the collective microsphere system.Extending my approach from acoustic to electromagnetic systems, I apply it to a collection of quantum dots: “artificial” two-level atoms with a size-dependent energy structure. The optical Maxwell-Bloch equations give the evolution of quantum dots under the influence of electromagnetic fields; this evolution then produces secondary radiation that couples a collection of quantum dots together. In my computational model, I castmy secondary electromagnetic fields in terms of a point-to-point integral operator that accurately recovers both near- and far-field effects. These fields, then, drive a set of implicitly coupled Bloch equations (solved with an exponentially-fitted predictor/corrector scheme) to give the dynamics of the system as a whole. In ensembles of up to 10 000 quantum dots, my model predicts synchronized multiplets of particles that exchange energy, quantum dots that dynamically couple to screen the effect of incident external radiation, localization of the polarization due to randomness and interactions, as well as wavelength-scale regionsof enhanced and suppressed polarization.The remainder of the work uses the same physical quantum dot system while moving towards efficient computer-aided device design. I detail an improved propagation algorithm to reduce the time and space complexity of the simulation dramatically, thereby facilitating rapid analysis of promising device structures. The algorithm makes use of physical and numerical approximations to effect large-scale calculations in reasonable CPU time. A rotating-frame approximation removes high-frequency components in the evolution of the system while simultaneously preserving accurate interference phenomena in space,thereby affording far larger simulation timesteps. Additionally, projecting the source current distribution onto a regular spatial grid makes use of a low-rank approximation to the field propagator to communicate radiation information between distant groups of particles via fast Fourier transforms in a manner reminiscent of fast multipole methods.
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Title: The evolutionary potential of populations on complex fitness landscapes
Creator: Bryson, David Michael
Date: 2012
Collection: Electronic Theses & Dissertations
Description: Evolution is a highly contingent process, where the quality of the solutions produced is affected by many factors. I explore and describe the contributions of three such aspects that influence overall evolutionary potential: the prior history of a population, the type and frequency of mutations that the organisms are subject to, and the composition of the underlying genetic hardware. I have systematically tested changes to a digital evolution system, Avida, measuring evolutionary potential in...
Show moreEvolution is a highly contingent process, where the quality of the solutions produced is affected by many factors. I explore and describe the contributions of three such aspects that influence overall evolutionary potential: the prior history of a population, the type and frequency of mutations that the organisms are subject to, and the composition of the underlying genetic hardware. I have systematically tested changes to a digital evolution system, Avida, measuring evolutionary potential in seven different computational environments ranging in complexity of the underlying fitness landscapes. I have examined trends and general principles that these measurements demonstrate and used my results to optimize the evolutionary potential of the system, broadly enhancing performance. The results of this work show that history and mutation rate play significant roles in evolutionary potential, but the final fitness levels of populations are remarkably stable to substantial changes in the genetic hardware and a broad range of mutation types.
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Title: The evolution of division of labor in digital organisms
Creator: Goldsby, Heather J.
Date: 2011
Collection: Electronic Theses & Dissertations
Description: Division of labor is a hallmark strategy employed by a wide variety of groups ranging in complexity from bacteria to human economies. Within these groups, some individuals, such as worker ants, sacrifice their ability to reproduce and instead dedicate their lives to the maintenance of the colony and success of their kin. A worker ant may spend its entire life performing a single task, such as defending the colony or tending to the brood. The complexity of the strategies employed by these...
Show moreDivision of labor is a hallmark strategy employed by a wide variety of groups ranging in complexity from bacteria to human economies. Within these groups, some individuals, such as worker ants, sacrifice their ability to reproduce and instead dedicate their lives to the maintenance of the colony and success of their kin. A worker ant may spend its entire life performing a single task, such as defending the colony or tending to the brood. The complexity of the strategies employed by these groups, combined with their rampant success, gives rise to questions regarding why division of labor exists. While extensive research has been done to better understand the patterns and mechanisms of division of labor, exploring this topic in an evolutionary context remains challenging to study due to the slow pace of evolution and imperfect historical data. Understanding how and why division of labor arises is pertinent not just for understanding biological phenomena, but also as a means to enable evolutionary computation techniques to address complex problems using problem decomposition. The objective of problem-decomposition approaches is to have a group of individuals cooperatively solve a complex task by breaking it into pieces, having specialist individuals solve the pieces, and reassembling the solution. Essentially, problem-decomposition approaches use division of labor to enable groups to solve more challenging problems than any individual could alone. Unfortunately, human engineers have struggled with creating effective, automated problem-decomposition approaches.In this dissertation, I use digital evolution (i.e., populations of self-replicating computer programs that undergo open-ended evolution) to investigate questions related to the evolution of division of labor and to apply these insights to problem decomposition techniques. This dissertation has three primary components: First, we provide experimental evidence that evolutionary computation techniques can evolve groups of individuals that exhibit division of labor. Second, we explore two hypotheses for the evolution of division of labor. Specifically, we find support for the hypothesis that temporal polyethism (i.e., where a worker's age is related to the task it performs within the colony) may result from the evolutionary pressures of aging and risks associated with tasks. Additionally, we find support for a hypothesis initially proposed by Adam Smith, the premier economist, that the presence of task-switching costs results in an increase in the amount of division of labor exhibited by groups. Third, we describe how our analyses revealed that groups of organisms evolved as part of our task-switching work exhibit complex problem decomposition strategies that can potentially be applied to other evolutionary computation challenges. This work both informs biological studies of division of labor and also provides insights that can enable the development of new mechanisms for using evolutionary computation to solve increasingly complex engineering problems.
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Title: The evolution of digital communities under limited resources
Creator: Walker, Bess Linden
Date: 2012
Collection: Electronic Theses & Dissertations
Description: Schluter (1996) describes adaptive radiation as "the diversification of a lineage into species that exploit a variety of different resource types and that differ in the morphological or physiological traits used to exploit those resources". My research focuses on adaptive radiation in the context of limited resources, where frequency-dependence is an important driver of selection (Futuyma & Moreno, 1988; Dieckmann & Doebeli, 1999; Friesen et al., 2004). Adaptive radiation yields a community...
Show moreSchluter (1996) describes adaptive radiation as "the diversification of a lineage into species that exploit a variety of different resource types and that differ in the morphological or physiological traits used to exploit those resources". My research focuses on adaptive radiation in the context of limited resources, where frequency-dependence is an important driver of selection (Futuyma & Moreno, 1988; Dieckmann & Doebeli, 1999; Friesen et al., 2004). Adaptive radiation yields a community composed of distinct organism types adapted to specific niches.I study simple communities of digital organisms, the result of adaptive radiation in environments with limited resources. I ask (and address) the questions: How does diversity, driven by resource limitation, affect the frequency with which complex traits arise? What other aspects of the evolutionary pressures in this limited resource environment might account for the increase in frequency with which complex traits arise? Can we predict community stability when it encounters another community, and is our prediction different for communities resulting from adaptive radiation versus those that are artificially assembled?Community diversity is higher in environments with limited resources than in those with unlimited resources. The evolution of an example complex feature (in this case, Boolean EQU) is also more common in limited-resource environments, and shows a strong correlation with diversity over a range of resource inflow rates. I show that populations evolving in intermediate inflow rates explore areas of the fitness landscape in which EQU is common, and that those in unlimited resource environments do not. Another feature of the limited-resource environments is the reduced cost of trading off the execution of building block tasks for higher-complexity tasks. I find strong causal evidence that this reduced cost is a factor in the more common evolution of EQU in limited-resource environments.When two communities meet in competition, the fraction of each community's descendants making up the final post-competition community is strongly consistent across replicates. I find that three community-level factors, ecotypic diversity, community composition, and resource use efficiency can be used to predict this fractional community success, explaining up to 35% of the variation.In summary, I demonstrate the value of digital communities as a tractable experimental system for studying general community properties. They sit at the bridge between ecology and evolutionary biology and evolutionary computation, and offer comprehensible ways to translate ideas across these fields.
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Title: The dynamics and scientific visualization for the electrophoretic deposition processing of suspended colloidal particles onto a reinforcement fiber
Creator: Robinson, Peter Timothy
Date: 1993
Collection: Electronic Theses & Dissertations

Title: The Köhler effect : intergroup competition using software-generated partners
Creator: Moss, Omotayo Micheal
Date: 2015
Collection: Electronic Theses & Dissertations
Description: Past research has examined the Köhler motivation gain effect (i.e., when an inferior team member performs better when paired with a more capable partner, from knowledge of his/her individual performance) in an active video game (AVG) using a superior, software-generated partner (SGP). The present investigation examined how incorporating a superior SGP into an AVG would affect an individual’s motivation when competing against one other human/virtual-partner team in an planking competition....
Show morePast research has examined the Köhler motivation gain effect (i.e., when an inferior team member performs better when paired with a more capable partner, from knowledge of his/her individual performance) in an active video game (AVG) using a superior, software-generated partner (SGP). The present investigation examined how incorporating a superior SGP into an AVG would affect an individual’s motivation when competing against one other human/virtual-partner team in an planking competition. Participants (N = 90 college-aged students) were randomly assigned to one of three conditions: individual control, conjunctive partner no competition (PNC), or conjunctive partner with opposing-team competition (PWT) in a 3 (conditions) x 2 (gender) factorial design. Participants performed the first series of five exercises alone, and after a rest period those in the partner conditions were told that they would do the remaining trials with a same-sex SGP whom they could observe during their performance. The partner’s performance was always superior to the participant’s. Participants were also told that they would work with their SGP as a team, and that the team’s score would be defined as the score of the person who stops holding the exercise first. Those in the opposing-team competition condition were also told that they and their virtual partner would be competing against one other human-virtual partner team. A significant motivation gain was observed in all partnered conditions compared to the control, F(2,89) = 15.63, p < .001, but the PNC and PWT groups were not significantly different from each other (p = 0.35). These findings suggest that competing against an opposing team does not ultimately boost the Köhler effect in AVGs.
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Title: Surface matching and chemical scoring to detect unrelated proteins binding similar small molecules
Creator: Van Voorst, Jeffrey Ryan
Date: 2011
Collection: Electronic Theses & Dissertations
Description: SURFACE MATCHING AND CHEMICAL SCORING TO DETECT UNRELATED PROTEINS BINDING SIMILAR SMALL MOLECULESByJeffrey Ryan Van VoorstHow can one deduce if two clefts or pockets in different protein structures bind the same small molecule if there is no significant sequence or structural similarity between the proteins? Human pattern recognition, based on extensive structural biology or ligand design experience, is the best choice when the number of sites is small. However, to be able to scale to the...
Show moreSURFACE MATCHING AND CHEMICAL SCORING TO DETECT UNRELATED PROTEINS BINDING SIMILAR SMALL MOLECULESByJeffrey Ryan Van VoorstHow can one deduce if two clefts or pockets in different protein structures bind the same small molecule if there is no significant sequence or structural similarity between the proteins? Human pattern recognition, based on extensive structural biology or ligand design experience, is the best choice when the number of sites is small. However, to be able to scale to the thousands of structures in structural databases requires implementing that experience as computational method. The primary advantage of such a computational tool is to be able to focus human expertise on a much smaller set of enriched binding sites.Although a number of tools have been developed for this purpose by many groups [61, 51, 86, 88, 91], to our knowledge, a basic hypothesis remains untested: two proteins that bind the same small molecule have binding sites with similar chemical and shape features, even when the proteins do not share significant sequence or structural similarity. A computational method to compare protein small molecule binding sites based on surface and chemical complementarity is proposed and implemented as a software package named SimSite3D. This method is protein structure based, does not rely on explicit protein sequence or main chain similarities, and does not require the alignment of atomic centers. It has been engineered to provide a detailed search of one fragment site versus a dataset of about 13,000 full ligand sites in 2&ndash4 hours (on one processor core).Several contributions are presented in this dissertation. First, several examples are presented where SimSite3D is able to find significant matches between binding sites that have similar ligand fragments bound but are unrelated in sequence or structure. Second, including the complementarity of binding site molecular surfaces helps to distinguish between sites that share a similar chemical motif, but do not necessarily bind the same molecule. Third, a number of clear examples are provided to illustrate the challenges in comparing binding sites which should be addressed in order for a binding site comparison method to gain widespread acceptance similar to that enjoyed by BLAST[3, 4]. Finally, an optimization method for addressing protein (and small molecule) flexibility in the context of binding site comparisons is presented, prototyped, and tested.Throughout the work, computational models were chosen to strike a delicate balance between achieving sufficient accuracy of alignments, discriminating between accurate and poor alignments, and discriminating between similar and dissimilar sites. Each of these criteria is important. Due to the nature of the binding site comparison problem, each criterion presents a separate challenge and may require compromises to balance performance to achieve acceptable performance in all three categories.At the present, the problem of addressing flexibility when comparing binding site surfaces has not been presented or published by any other research group. In fact, the problem of modeling flexibility to determine correspondences between binding sites is an untouched problem of great importance. Therefore, the final goal of this dissertation is to prototype and evaluate a method that uses inverse kinematics and gradient based optimization to optimize a given objective function subject to allowed protein motions encoded as stereochemical constraints. In particular, we seek to simultaneously maximize the surface and chemical complementarity of two closely aligned sites subject to directed changes in side chain dihedral angles.
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Title: Suicide, signals, and symbionts : evolving cooperation in agent-based systems
Creator: Vostinar, Anya E.
Date: 2017
Collection: Electronic Theses & Dissertations
Description: Cooperation is ubiquitous in nature despite the constant pressure for organisms to cheat by receiving a benefit from cooperators, while not cooperating themselves. The continued evolution and persistence of countless forms of cooperation is a central topic in evolutionary theory. Extensive research has been done on the theoretical dynamics of cooperation through game theory and the natural examples of cooperation. However, it remains difficult to understand thoroughly the evolution of many...
Show moreCooperation is ubiquitous in nature despite the constant pressure for organisms to cheat by receiving a benefit from cooperators, while not cooperating themselves. The continued evolution and persistence of countless forms of cooperation is a central topic in evolutionary theory. Extensive research has been done on the theoretical dynamics of cooperation through game theory and the natural examples of cooperation. However, it remains difficult to understand thoroughly the evolution of many cooperative systems, due in part to the ancient origins of these systems and the long time scales required to see cooperation evolve in any natural populations. I have systematically analyzed the evolution of three broad types of cooperation: programmed cell death, quorum sensing, and mutualisms (cooperation across species). I have provided evidence that programmed cell death can originate due to kin selection. I have also created two new systems to enable the extensive exploration of factors that affect the evolution of public goods cooperation and mutualism. Using these systems, I determine the effects of environmental factors on the evolution of public goods cooperation and mutualism. By uniting the expansive theoretical work on these forms of cooperation with a fully-controlled experimental system, I contributed to our understanding of how these forms of cooperation can emerge and be maintained in industrial and medical applications that rely on bacterial cooperation.
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Title: Still learning : introducing the learning transfer model, a formal model of transfer
Creator: Olenick, Jeffrey David
Date: 2020
Collection: Electronic Theses & Dissertations
Description: Although training has been a key topic of study in organizational psychology for over a century, a century which has seen great progress in our understanding of what a quality training program entails, a substantial gap persists between what is trained and what is transferred to the job. Reduction of the training-transfer gap has driven research on transfer-focused interventions which have proven effective. However, although we know a lot regarding how individuals learn new material, and...
Show moreAlthough training has been a key topic of study in organizational psychology for over a century, a century which has seen great progress in our understanding of what a quality training program entails, a substantial gap persists between what is trained and what is transferred to the job. Reduction of the training-transfer gap has driven research on transfer-focused interventions which have proven effective. However, although we know a lot regarding how individuals learn new material, and correlates of whether they transfer that material back to their work environment, we know very little about how individuals go about choosing whether to apply their new knowledge to, typically, previously-encountered situations in their work environment and how those decisions unfold over time. Improving our knowledge regarding how individuals transfer learned material will lead to new insights on how to support the transfer of organizationally directed training, or any learning event, back to the work environment. Thus, the present paper introduces a formal model of the transfer process, the Learning Transfer Model (LTM), which proposes a process for how transfer unfolds over time and gives rise to many of the findings we have accumulated in the transfer literature. This is accomplished by reconceptualizing transfer as its own learning process which is affected by the dual nature of human cognitive systems, the learner's social group, and their self-regulatory processes. The LTM was then instantiated in a series of computational models for virtual experimentation. Findings and implications for research and practice are discussed throughout.
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Title: Simulation of batch drying rice
Creator: Chan, Nguyen Kim
Date: 1976
Collection: Electronic Theses & Dissertations

Title: Shelf life estimation of USP 10mg Prednisone calibrator tablets in relation to dissolution & new windows-based shelf life computer program
Creator: Yoon, Seungyil
Date: 2000
Collection: Electronic Theses & Dissertations

Title: Sensitivities of simulated fire-induced flows to fire shape and background wind profile using a cloud-resolving model
Creator: Stageberg, Marshall S.
Date: 2018
Collection: Electronic Theses & Dissertations
Description: Wildland fire behavior can be very difficult to predict because of inherent non-linearities and multi-scale processes associated with fire-atmosphere interactions. Circulations and complex flows in the vicinity of a fire are driven by heat release from the fire. Since extreme conditions in the fire environment make collecting meteorological observations difficult, we employ a high-resolution numerical model to simulate the atmospheric responses to a fire. Specifically, we have chosen Cloud...
Show moreWildland fire behavior can be very difficult to predict because of inherent non-linearities and multi-scale processes associated with fire-atmosphere interactions. Circulations and complex flows in the vicinity of a fire are driven by heat release from the fire. Since extreme conditions in the fire environment make collecting meteorological observations difficult, we employ a high-resolution numerical model to simulate the atmospheric responses to a fire. Specifically, we have chosen Cloud Model 1 (CM1) because it is designed to simulate high resolution, cloud scale processes that are comparable in scale to fire-induced flows. A surface sensible heat flux is added to CM1 to simulate the effect of a fire and the resultant fire-induced circulations and complex flows are examined. Using CM1 allows us to produce simulations with fine spatial and temporal resolution with a detailed representation of the evolution of the fire-atmosphere system. For the purpose of this study, we perform a series of simulations to examine the sensitivity of fire-induced flows to the shape of the simulated fire and to background wind profile. We show how fire shape and the background wind profile affect the intensity and extent of fire-induced perturbations to the lower atmosphere. The results from these numerical simulations, when combined with field observations, help improve our understanding of fire-atmosphere interactions. The results from this study can potentially help fire managers with decision-making when fighting wildland fires.
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