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Title: THE INFLUENCE OF VIRTUAL MANIPULATIVES ONSECOND GRADER'S ACQUISITION OF PLACE VALUE CONCEPTS.
Creator: Jolicoeur, Kay, Dixon, Juli, University of Central Florida
Abstract / Description: The purpose of this study was to examine my own practice of teaching place value and the influence virtual manipulatives had, in addition to physical manipulatives, on place value understanding of my second grade students. I wanted to see how adding a base-ten computer applet might better meet the needs of all learners while also meeting the needs of today's technological classroom. Through this study, I found that both physical and virtual manipulatives helped students acquire place value...
Show moreThe purpose of this study was to examine my own practice of teaching place value and the influence virtual manipulatives had, in addition to physical manipulatives, on place value understanding of my second grade students. I wanted to see how adding a base-ten computer applet might better meet the needs of all learners while also meeting the needs of today's technological classroom. Through this study, I found that both physical and virtual manipulatives helped students acquire place value concepts. I found that virtual manipulatives had features that engaged students in a way that increased their mathematical language, increased students' ability to represent more conceptual understanding of composing and decomposing numbers, and express enthusiasm towards mathematics. A pretest and posttest revealed that students' academic performance increased. While research on virtual manipulatives and mathematical achievement is fairly recent, this study offers insight to other classroom teachers and the research community.
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Date Issued: 2011
Identifier: CFE0003763, ucf:48799
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0003763

Title: THE EFFECT OF MATHEMATICAL MANIPULATIVE MATERIALS ON THIRD GRADE STUDENTS' PARTICIPATION, ENGAGEMENT, AND ACADEMIC PERFORMANCE.
Creator: Ross, Caryn, Gresham, Regina, University of Central Florida
Abstract / Description: This study is the summary of research conducted in a third grade classroom during a unit on multi-digit addition and subtraction. The classroom teacher utilized mathematical manipulative materials throughout the course of this unit as a supplement to aid in the conceptual understanding of addition and subtraction. This study showed the effects of those manipulatives on third grade students' participation, engagement, and academic performance. Data collected from teacher observations and...
Show moreThis study is the summary of research conducted in a third grade classroom during a unit on multi-digit addition and subtraction. The classroom teacher utilized mathematical manipulative materials throughout the course of this unit as a supplement to aid in the conceptual understanding of addition and subtraction. This study showed the effects of those manipulatives on third grade students' participation, engagement, and academic performance. Data collected from teacher observations and video recordings indicated a positive relationship between manipulatives and student participation and engagement. A pre-test/post-test and student work samples were used to determine effects on academic performance. Data showed students' academic performance increased, however the relationship between academic performance and manipulatives was found to require further research and study.
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Date Issued: 2008
Identifier: CFE0002092, ucf:47544
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0002092

Title: Thermally induced motion, collision and mixing of levitated droplets.
Creator: Davanlou, Ashkan, Kumar, Ranganathan, Cho, Hyoung Jin, Deng, Weiwei, Mansy, Hansen, Shivamoggi, Bhimsen, University of Central Florida
Abstract / Description: This dissertation investigates the motion of a levitated droplet experimentally and analytically against the Marangoni flow in an immiscible outer fluid at higher speeds than is possible currently. Based on our earlier experiments, when a droplet is released from a height of 1.5 (-) 4 times its diameter from the liquid surface, it can overcome the impact and stay levitated at the liquid-air interface due to the existence of an air gap between the droplet and the liquid film. In order to...
Show moreThis dissertation investigates the motion of a levitated droplet experimentally and analytically against the Marangoni flow in an immiscible outer fluid at higher speeds than is possible currently. Based on our earlier experiments, when a droplet is released from a height of 1.5 (-) 4 times its diameter from the liquid surface, it can overcome the impact and stay levitated at the liquid-air interface due to the existence of an air gap between the droplet and the liquid film. In order to explain this behavior of droplet traveling against the counter-current motion, we propose a simple approach: first, the Marangoni convection inside the thin film is considered without the droplet floating on the surface. By using a level-set method and solving the Navier-Stokes equation, the free surface velocity and deformation are calculated. Then, these quantities are used to solve for droplet velocity and drag coefficient simultaneously using a force balance. In order to compare the simulation results, experiments with levitated water droplets on an immiscible carrier liquid, FC-43, were conducted for various temperature gradients, and droplet velocities were measured at different locations using high-speed imaging. The experimental results are in good agreement with the developed theoretical model. For a Reynolds number range of 2-32, it is shown that the drag coefficients are up to 66% higher than those for the fully immersed sphere at the same Reynolds numbers. A correlation is proposed to calculate the drag coefficient of levitated droplets for various temperature drops across the channel.For the first time, it is shown that it is possible to realize the natural coalescence of droplets through Marangoni effect without any external stimulation, and deliver the coalesced droplet to a certain destination through the use of surface tension gradients. The effects of the various shapes and sizes upon collision are studied. Regions of coalescence and stretching separation of colliding droplets are delineated based on Weber number and impact number. The existence of the transition line between coalescence and stretching separation in this passive mode of transport is similar to what was observed in the literature for forced coalescence at significantly higher Weber numbers. It is also found that a thermocapillary environment improves the mixing process. In order to illustrate and quantify the mixing phenomenon, the dispensed droplets were made of potassium hydroxide and phenolphthalein which is used as a pH indicator. The experiments show the possibility to reach mixing rates as high as 74% within 120 ms. This study offers new insight to thermo-coalescence and demonstrates how natural coalescence could be used to transport, mix and collect biochemical assays more efficiently. The results of this research can be engineered to enhance the performance of self-cleaning surfaces and micro-total analysis systems ((&)#181;TAS), where sample transport, filtration, chemical reactions, separation and detection are of great interest.
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Date Issued: 2015
Identifier: CFE0006213, ucf:51106
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0006213

Title: LISTENING TO STUDENT VOICES: FIFTH GRADERS' PERCEPTIONS OF THEIR MATHEMATICS LEARNING WITHIN THE CONTEXT OF A MATHEMATICS REFORM EFFORT.
Creator: Hoffman, Elizabeth, Killingsworth Roberts, Sherron, University of Central Florida
Abstract / Description: This qualitative study explored fifth graders' perceptions of their mathematics learning within the context of a reform effort. Students' voices are the focus of this study due to the paucity of literature on student learning from the students' perspective (Erickson & Shultz, 1992), particularly the elementary student (Gentilucci, 2004). The participants of this study, who in the past have been given a variety of labels including "disadvantaged" or "at-risk," clearly articulated, even in...
Show moreThis qualitative study explored fifth graders' perceptions of their mathematics learning within the context of a reform effort. Students' voices are the focus of this study due to the paucity of literature on student learning from the students' perspective (Erickson & Shultz, 1992), particularly the elementary student (Gentilucci, 2004). The participants of this study, who in the past have been given a variety of labels including "disadvantaged" or "at-risk," clearly articulated, even in nonstandard English, their perceptions of their mathematics learning. They passionately explained what helped them learn mathematics as well as what impeded their mathematics learning and were often incredibly insightful in their commentary. In an effort to hear and present the student voices, the data gathering methods used in this study included the use of focus groups, one-on-one interviews, and classroom observations as well as the use of a student survey. Several ethnographic methods and practices were employed to help ensure the credibility of this study, including triangulation and member checking. Data analysis involved a highly detailed, organic process which culminated in the emergence of a number of significant themes involving students' perspectives of mathematics, their mathematics experiences prior to fifth grade, and finally their perspectives of their learning during the first year of a mathematics reform effort. A number of valuable lessons learned as a result of this study are presented and translated into implications for the elementary mathematics classroom. These lessons, based on the students' own voices, urge teachers to prioritize mathematics instruction, effectively utilize manipulatives, games, and alternative algorithms as well as encourage classroom discourse about mathematics. If teachers would follow this outline, provided by the students' voices, students' mathematical power will be more deeply realized. Additionally, the promise of true reform due to the transformational power of students' voices is discussed and the possibilities defined.
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Date Issued: 2006
Identifier: CFE0000973, ucf:46693
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0000973

Title: HEBREW AND COMPUTER-MEDIATED COMMUNICATION: THE EFFECTS OF A LANGUAGE MANIPULATION ON PERCEPTION, IDENTITY, AND PRESERVATION.
Creator: Nir, Tamar, Sims, Valerie K., University of Central Florida
Abstract / Description: This study aimed to explore the ways in which Hebrew is currently being manipulated online through a linguistic deviation called Fakatsa. In this study, participants were asked to rate random statements of frivolous or serious topics in either standard grammatical Hebrew or Fakatsa Hebrew conditions on specific judgment values. It was hypothesized that participants would rate the Fakatsa writer negatively on certain characteristics, such as intelligence, education, religiosity, and...
Show moreThis study aimed to explore the ways in which Hebrew is currently being manipulated online through a linguistic deviation called Fakatsa. In this study, participants were asked to rate random statements of frivolous or serious topics in either standard grammatical Hebrew or Fakatsa Hebrew conditions on specific judgment values. It was hypothesized that participants would rate the Fakatsa writer negatively on certain characteristics, such as intelligence, education, religiosity, and nationalism and positively on other characteristics, such as femininity and creativity. Twenty-four participants completed this experiment. Results showed that participants responded as expected for certain negative attributes typical of Fakatsa and deviations to computer-mediated communication and did not respond as expected for any the positive attributes typical of Fakatsa. The results showed that fluent Hebrew speakers viewed users of the Fakatsa manipulation differently than users of standard Hebrew and may suggest personal biases and perceptions when encountering computer-mediated communication.
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Date Issued: 2016
Identifier: CFH2000043, ucf:45531
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFH2000043

Title: THERMALLY-INDUCED MOTION OF DROPLETS ON A THIN LIQUID LAYER AND ITS APPLICATION TO DROPLET MANIPULATION PLATFORMS.
Creator: Yakhshi-Tafti, Ehsan, Kumar, Ranganathan, University of Central Florida
Abstract / Description: In the recent years, there has been a growing interest in droplet-based (digital) microfluidic systems due to their ability to handle multiple discrete samples in a self-contained configuration compared to continuous flow systems. Various methods for droplet manipulation are currently available based on hydrodynamic, electrostatic, chemical, photonic and thermal interactions. High speed, controlled response and minimal thermal loading with least contamination are required in practical...
Show moreIn the recent years, there has been a growing interest in droplet-based (digital) microfluidic systems due to their ability to handle multiple discrete samples in a self-contained configuration compared to continuous flow systems. Various methods for droplet manipulation are currently available based on hydrodynamic, electrostatic, chemical, photonic and thermal interactions. High speed, controlled response and minimal thermal loading with least contamination are required in practical applications, especially in chemistry and biology. Although, thermal actuation of droplets has been recognized as an attractive choice due to a wide range of thermomechanical properties that can be exploited, the previous studies yielded limited success in addressing issues such as droplet evaporation, contamination, pinning, hysteresis and irreversibility that are associated with using solid substrate platforms In order to overcome shortcomings of traditional approaches, a novel thermally-actuated droplet manipulation platform based on using an inert liquid film was proposed and its working mechanisms were studied. Droplets at the air-liquid interface of immiscible liquids usually form partially-submerged lens shapes (e.g. water on oil). In the thermally-induced motion of droplets on the free surface of immiscible liquid films, lens-shaped droplets move from warm toward cooler regions. In addition to this structure, we showed that droplets released from critical heights above the target liquid can sustain the impact and at the end maintain a spherical ball-shape configuration above the surface, despite undergoing large deformation. It was discovered in this study that such spherical droplets migrate in the opposite direction to lens droplets when subject to a thermal gradient; i.e. direction of increasing temperatures. The existence of this metastable spherical state above the free surface and its transition into more stable lens configuration was investigated using optical diagnostic tools and theoretical analysis. Opposite direction of motion observed for droplets at the free surface of immiscible liquids was explained based on droplet shape at the interface and the dynamics of thin liquid films subject to lateral thermal gradients: mainly 1) deformation of the free surface and 2) development of an outward moving flow (hot to cold) at the free surface due to surface tension gradients caused by thermal gradients. A lens droplet moves due to the free surface flow caused by Marangoni convection which is from hot to cold. On the other hand, the spherical droplet moves towards the maximum depression on the free surface, occurring at the hottest region as a result of the balance between gravity and drag forces from the opposing free surface flow. The proposed theoretical models predict experimental observations of droplet motion due to thermal gradients satisfactorily. Opposite responses of thermally-induced motion of lens and spherical droplets on a thin liquid layer, were characterized experimentally and compared to theory by studying droplet motion in an exponentially-decaying temperature field maintained across the length of a shallow liquid layer. The effect of droplet size and magnitude of thermal gradient (slope) on drop velocity were investigated. The down-scaling effect is prominent, which shows that the proposed concept of droplet manipulation could be used favorably in miniaturized platforms. Based on the theoretical development and measurements obtained from meso-scale experiments, a silicon-based droplet transportation platform with embedded metal film micro heaters was developed. A thin layer of a chemically-inert and thermally stable liquid was chosen as the carrier liquid. Heaters were interfaced with control electronics and driven through a computer graphical user interface. By creating appropriate spatio-temporal thermal gradient maps, transport of droplets on predetermined pathways was demonstrated with a high level of controllability and speed.
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Date Issued: 2010
Identifier: CFE0003547, ucf:48908
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0003547

Title: Kinematical Modelling and Its Analytical Inverse Kinematic Solution for the Handling Mechanism of an Agricultural Robot.
Creator: Defterli, Sinem, Xu, Yunjun, Lin, Kuo-Chi, Zheng, Qipeng, Song, Sang-Eun, University of Central Florida
Abstract / Description: Early detection of the crop diseases helps to prevent failure in the amount and the quality of the production. In agricultural robotics, the idea of a disease detection robot is a fresh and an innovative hot-button topic. The exclusion of the diseased parts from the strawberry plants for further analyses is one of the main tasks of a recently developed strawberry robot. To this purpose, the handling mechanism in the robot needs to achieve an accurate manipulation task to reach the target....
Show moreEarly detection of the crop diseases helps to prevent failure in the amount and the quality of the production. In agricultural robotics, the idea of a disease detection robot is a fresh and an innovative hot-button topic. The exclusion of the diseased parts from the strawberry plants for further analyses is one of the main tasks of a recently developed strawberry robot. To this purpose, the handling mechanism in the robot needs to achieve an accurate manipulation task to reach the target. Reaching, cutting and storing the diseased leaf are challenging and delicate processes during the procedure of the handling mechanism operation in the field.The manipulation task of the mechanism is succeeded when the inverse kinematic relations from workspace to joint space are defined properly. The inverse kinematic analysis is usually subjected to the restrictions due to the limitations in mechanical design of the mechanism, hardware components and operation environment of the robots as well as the morphology of the target. This study proposes a set of analytical algorithms to solve the inverse kinematics problem of the handling mechanism under certain constraints. First, proposed analytical approach is based on the calculation of the joint variables by solving only the 3D position information of the target since the output from image processing algorithms of vision subsystem in the ground robot is only the location of the diseased point. The position of target point is the only output from vision subsystem and this data will be given as an input to the proposed algorithms. Second, the mechanism has certain restrictions on its geometrical construction and the joint actuators' capacity. Hence, these restrictions limit the range of joint variables to be solved. Due to sudden and unpredicted nature of field conditions, the quickness of handling mechanism inverse kinematics solution's execution has a vital effect on the success of the picking task of the robot. Another essential factor is to use the battery life of the robot effectively, by minimizing energy consumption. Therefore, the effectiveness of the proposed algorithm is decided by comparing the developed performance indices of consumed energy and CPU time cost via numerical solution namely, a nonlinear constrained optimization method under same restrictions of inverse kinematics problem. Performance of both algorithms is observed by the simulations in MATLAB(&)#174; and laboratory set-up experiments.
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Date Issued: 2016
Identifier: CFE0006291, ucf:51588
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0006291

Title: Supporting Middle School Students with Emotional or Behavioral Disorders in Blended Learning: A Fraction Intervention using Virtual Manipulatives.
Creator: Serianni, Barbara, Dieker, Lisa, Marino, Matthew, Vasquez, Eleazar, Basham, James, University of Central Florida
Abstract / Description: Students with emotional or behavioral disorders (EBD) are more likely than other students with disabilities to drop out of school (Blackorby (&) Wagner, 1996) and suffer societal consequences that include higher probabilities and rates of incarceration, poverty, drug abuse, homelessness, low wages, and unemployment (Bradley, Doolittle, (&) Bartolotta, 2008; Wagner, 1995). High school graduation is a critical factor to improve post-secondary outcomes for students with EBD; yet it is often...
Show moreStudents with emotional or behavioral disorders (EBD) are more likely than other students with disabilities to drop out of school (Blackorby (&) Wagner, 1996) and suffer societal consequences that include higher probabilities and rates of incarceration, poverty, drug abuse, homelessness, low wages, and unemployment (Bradley, Doolittle, (&) Bartolotta, 2008; Wagner, 1995). High school graduation is a critical factor to improve post-secondary outcomes for students with EBD; yet it is often mathematics, specifically algebra, that stands in the way of graduation (Blackorby (&) Wagner). Students with EBD often enter middle school lacking foundational mathematics skills, such as fractions, which sets them up to struggle with pre-algebra and ultimately fail algebra (U.S. Department of Education, 2008). The purpose of this study was to improve the ability of middle school students with EBD to access online grade-level mathematics content by providing fraction remediation to improve conceptual fraction knowledge and procedural fluency. The intervention consisted of Initial Fraction Ideas, an intervention curriculum from the Rational Number Project (RNP; Cramer, Behr, Post, (&) Lesh, 2009), in conjunction with three online virtual manipulatives (VM). The unique blended learning environment of this study provided the opportunity to evaluate the use of an evidence-based fraction intervention, in conjunction with VMs, in a single subject, multiple baseline across subjects design. Fluency data was gathered from daily fraction addition assessments (FAA) administered after each intervention session. A second component of the study featured a non-experimental repeated measures design that assessed student conceptual understanding of fraction equivalency through the administration of pre, post, and delayed-post Equivalent Fraction Tests (EFT). The intervention was effective in producing increases in median group fluency with high effect sizes, across three replications, establishing a functional relationship between the intervention and the dependent variable for these groups of students with EBD. In addition, all groups posted mean gains in equivalent fraction knowledge from pre to post-EFT, and maintained those gains for at least 15 days after the intervention concluded.
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Date Issued: 2014
Identifier: CFE0005415, ucf:50435
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0005415

Title: DIRECT MANIPULATION OF VIRTUAL OBJECTS.
Creator: Nguyen, Long, Malone, Linda, University of Central Florida
Abstract / Description: Interacting with a Virtual Environment (VE) generally requires the user to correctly perceive the relative position and orientation of virtual objects. For applications requiring interaction in personal space, the user may also need to accurately judge the position of the virtual object relative to that of a real object, for example, a virtual button and the user's real hand. This is difficult since VEs generally only provide a subset of the cues experienced in the real world....
Show moreInteracting with a Virtual Environment (VE) generally requires the user to correctly perceive the relative position and orientation of virtual objects. For applications requiring interaction in personal space, the user may also need to accurately judge the position of the virtual object relative to that of a real object, for example, a virtual button and the user's real hand. This is difficult since VEs generally only provide a subset of the cues experienced in the real world. Complicating matters further, VEs presented by currently available visual displays may be inaccurate or distorted due to technological limitations. Fundamental physiological and psychological aspects of vision as they pertain to the task of object manipulation were thoroughly reviewed. Other sensory modalities – proprioception, haptics, and audition – and their cross-interactions with each other and with vision are briefly discussed. Visual display technologies, the primary component of any VE, were canvassed and compared. Current applications and research were gathered and categorized by different VE types and object interaction techniques. While object interaction research abounds in the literature, pockets of research gaps remain. Direct, dexterous, manual interaction with virtual objects in Mixed Reality (MR), where the real, seen hand accurately and effectively interacts with virtual objects, has not yet been fully quantified. An experimental test bed was designed to provide the highest accuracy attainable for salient visual cues in personal space. Optical alignment and user calibration were carefully performed. The test bed accommodated the full continuum of VE types and sensory modalities for comprehensive comparison studies. Experimental designs included two sets, each measuring depth perception and object interaction. The first set addressed the extreme end points of the Reality-Virtuality (R-V) continuum – Immersive Virtual Environment (IVE) and Reality Environment (RE). This validated, linked, and extended several previous research findings, using one common test bed and participant pool. The results provided a proven method and solid reference points for further research. The second set of experiments leveraged the first to explore the full R-V spectrum and included additional, relevant sensory modalities. It consisted of two full-factorial experiments providing for rich data and key insights into the effect of each type of environment and each modality on accuracy and timeliness of virtual object interaction. The empirical results clearly showed that mean depth perception error in personal space was less than four millimeters whether the stimuli presented were real, virtual, or mixed. Likewise, mean error for the simple task of pushing a button was less than four millimeters whether the button was real or virtual. Mean task completion time was less than one second. Key to the high accuracy and quick task performance time observed was the correct presentation of the visual cues, including occlusion, stereoscopy, accommodation, and convergence. With performance results already near optimal level with accurate visual cues presented, adding proprioception, audio, and haptic cues did not significantly improve performance. Recommendations for future research include enhancement of the visual display and further experiments with more complex tasks and additional control variables.
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Date Issued: 2009
Identifier: CFE0002822, ucf:48060
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0002822

Title: Bio-Inspired Visual Servo Control of a Picking Mechanism in an Agricultural Ground Robot.
Creator: Defterli, Sinem, Xu, Yunjun, Kauffman, Jeffrey L., Lin, Kuo-Chi, Song, Sang-Eun, Zheng, Qipeng, University of Central Florida
Abstract / Description: For a recently constructed disease detection agricultural ground robot, the segregation of unhealthy leaves fromstrawberry plants is a major task of the robot's manipulation subsystem in field operations. In this dissertation, the motion planning of a custom-designedpicking mechanism in the ground robot's subsystem is studied in two sections. First, a set of analytical, suboptimal semi-analyticaland numerical algorithms are studied to solve the inverse kinematics problem of the handling...
Show moreFor a recently constructed disease detection agricultural ground robot, the segregation of unhealthy leaves fromstrawberry plants is a major task of the robot's manipulation subsystem in field operations. In this dissertation, the motion planning of a custom-designedpicking mechanism in the ground robot's subsystem is studied in two sections. First, a set of analytical, suboptimal semi-analyticaland numerical algorithms are studied to solve the inverse kinematics problem of the handling mechanism in firmcircumstances. These premeditated approaches are built on the computation of the joint variables by an identified 3Dposition data of the target leaf only. The outcomes of the three solution algorithms are evaluated in terms of the performanceindexes of energy change and the CPU time cost. The resultant postures of the mechanism for different target pointlocations are observed both in simulations and the hardware experiments with each IK solution. Secondly, after the manipulation task of the mechanism via the proposed inverse kinematicalgorithms is performed, some compensation may be needed due to the sudden and unpredicted deviation of the targetposition under field conditions.For the purpose of finding optimal joint values under certain constraints, a trajectory optimization problem in image-based visual servoing method via the camera-in-handconfiguration is initiated when the end-effector is in the close proximity of the target leaf. In this part of the study, a bio-inspired trajectory optimization problem in image-basedvisual servoing method is constructed based on the mathematical model derived from the prey-predatorrelationships in nature. In this biological phenomenon, the predator constructs its path in a certain subspace whilecatching the prey. When this motion strategy is applied to trajectory optimization problems, it causes a significantreduce in the computation cost since it finds the optimum solution in a certain manifold. The performance of the introducedbio-inspired trajectory optimization in visual servoing is validated with the hardware experiments both in laboratory settings and in fieldconditions.
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Date Issued: 2018
Identifier: CFE0007170, ucf:52247
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0007170

Title: IMPACT OF LANDSCAPE MANAGEMENT ON HOUSE MICE (MUS MUSCULUS) AND RED IMPORTED FIRE ANTS (SOLENOPSIS INVICTA).
Creator: Abelson, Jesse, Jenkins, David, University of Central Florida
Abstract / Description: Understanding of mechanisms that limit the abundance and distribution of species is central to ecology. The failure of mechanisms to regulate populations can result in population outbreaks. There have been two outbreaks of house mice in the past decade in central Florida. In my study, I examine the efficacy of landscape management in the form of mowing and plowed soil barriers to limit or prevent outbreaks of house mice in a former agricultural area. House mouse populations were highly...
Show moreUnderstanding of mechanisms that limit the abundance and distribution of species is central to ecology. The failure of mechanisms to regulate populations can result in population outbreaks. There have been two outbreaks of house mice in the past decade in central Florida. In my study, I examine the efficacy of landscape management in the form of mowing and plowed soil barriers to limit or prevent outbreaks of house mice in a former agricultural area. House mouse populations were highly variable, but were unaffected by mowing or plowed soil barriers. Red imported fire ants were ubiquitous in the study area regardless of land management treatments. Control of fire ants did not result in more house mice on treated plots.
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Date Issued: 2011
Identifier: CFE0003590, ucf:48899
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0003590

Title: The Influence of Choice in Manipulatives on Second Grade Students' Attitudes, Achievement, and Explanations of Two-Digit Addition Concepts.
Creator: Siegel, Aryn, Andreasen, Janet, Dieker, Lisa, Dixon, Juli, University of Central Florida
Abstract / Description: The purpose of this study was to improve my teaching practice, as well as my second grade students' success with two-digit addition concepts, by allowing them to choose the manipulative tools to explore problems and justify solutions. I examined how allowing my students this choice influenced their attitudes, achievement, and explanations of their thought processes. I found that allowing students to choose their own manipulatives had positive influences in all three areas. Pre- and post-test...
Show moreThe purpose of this study was to improve my teaching practice, as well as my second grade students' success with two-digit addition concepts, by allowing them to choose the manipulative tools to explore problems and justify solutions. I examined how allowing my students this choice influenced their attitudes, achievement, and explanations of their thought processes. I found that allowing students to choose their own manipulatives had positive influences in all three areas. Pre- and post-test results showed an overall shift toward more positive mathematics attitudes, as well as increased academic achievement with two-digit addition concepts. Students also demonstrated changes in the ways they used the manipulatives, as well as how they explained their solutions to two-digit addition problems.
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Date Issued: 2012
Identifier: CFE0004267, ucf:49540
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0004267

Title: DEEP WITHIN.
Creator: Joseph, Caberbe, Haxton, David, University of Central Florida
Abstract / Description: As a contemporary photographer, I focus most on light and color to bring out the uniqueness of my images. Photography is about lighting and I manipulate lights to raise questions in my viewers. Manipulating light is my way of being curious about how it may change mood physically and emotionally. Inspired by classical paintings, I have developed a body of photographs that can be admired by anyone. Although the main focus of my work is light and color, this body of work is also intended to...
Show moreAs a contemporary photographer, I focus most on light and color to bring out the uniqueness of my images. Photography is about lighting and I manipulate lights to raise questions in my viewers. Manipulating light is my way of being curious about how it may change mood physically and emotionally. Inspired by classical paintings, I have developed a body of photographs that can be admired by anyone. Although the main focus of my work is light and color, this body of work is also intended to empower those with little confidence in themselves and those who have been rejected, abused, or mistrusted.
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Date Issued: 2009
Identifier: CFE0002592, ucf:48286
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0002592

Title: STRUCTURAL, ELECTRONIC, VIBRATIONAL AND THERMODYNAMICAL PROPERTIES OF SURFACES AND NANOPARTICLES.
Creator: Yildirim, Handan, Rahman, Talat S., University of Central Florida
Abstract / Description: The main focus of the thesis is to have better understanding of the atomic and electronic structures, vibrational dynamics and thermodynamics of metallic surfaces and bi-metallic nanoparticles (NPs) via a multi-scale simulational approach. The research presented here involves the study of the physical and chemical properties of metallic surfaces and NPs that are useful to determine their functionality in building novel materials. The study follows the Ã‚Â"bottom-upÃ&...
Show moreThe main focus of the thesis is to have better understanding of the atomic and electronic structures, vibrational dynamics and thermodynamics of metallic surfaces and bi-metallic nanoparticles (NPs) via a multi-scale simulational approach. The research presented here involves the study of the physical and chemical properties of metallic surfaces and NPs that are useful to determine their functionality in building novel materials. The study follows the Ã‚Â"bottom-upÃ‚Â" approach for which the knowledge gathered at the scale of atoms and NPs serves as a base to build, at the macroscopic scale, materials with desired physical and chemical properties. We use a variety of theoretical and computational tools with different degrees of accuracy to study problems in different time and length scales. Interactions between the atoms are derived using both Density Functional Theory (DFT) and Embedded Atom Method (EAM), depending on the scale of the problem at hand. For some cases, both methods are used for the purpose of comparison. For revealing the local contributions to the vibrational dynamics and thermodynamics for the systems possessing site-specific environments, a local approach in real-space is used, namely Real Space GreenÃ‚Â's Function method (RSGF). For simulating diffusion of atoms/clusters and growth on metal surfaces, Molecular Statics (MS) and Molecular Dynamics (MD) methods are employed.
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Date Issued: 2010
Identifier: CFE0003064, ucf:48300
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0003064

Title: Smart Grasping using Laser and Tactile Array Sensors for UCF-MANUS- An Intelligent Assistive Robotic Manipulator.
Creator: Prakash, Kiran, Behal, Aman, Boloni, Ladislau, Haralambous, Michael, University of Central Florida
Abstract / Description: This thesis presents three improvements in the UCF MANUS Assistive Robotic Manipulator's grasping abilities. Firstly, the robot can now grasp objects that are deformable, heavy and have uneven contact surfaces without undergoing slippage during robotic operations, e.g. paper cup, filled water bottle. This is achieved by installing a high precision non-contacting Laser sensor1 that runs with an algorithm that processes raw-input data from the sensor, registers smallest variation in the...
Show moreThis thesis presents three improvements in the UCF MANUS Assistive Robotic Manipulator's grasping abilities. Firstly, the robot can now grasp objects that are deformable, heavy and have uneven contact surfaces without undergoing slippage during robotic operations, e.g. paper cup, filled water bottle. This is achieved by installing a high precision non-contacting Laser sensor1 that runs with an algorithm that processes raw-input data from the sensor, registers smallest variation in the relative position of the object with respect to the gripper. Secondly, the robot can grasp objects that are as light and small as single cereal grain without deforming it. To achieve this a MEMS Barometer based tactile sensor array device that can measure force that are as small as 1 gram equivalent is embedded into the gripper to enhance pressure sensing capabilities. Thirdly, the robot gripper gloves are designed aesthetically and conveniently to accommodate existing and newly added sensors using a 3D printing technology that uses light weight ABS plastic as a fabrication material. The newly designed system was experimented and found that a high degree of adaptability for different kinds of objects can be attained with a better performance than the previous system.
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Date Issued: 2016
Identifier: CFE0006164, ucf:51119
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0006164

Title: A MULTI-LAYER FPGA FRAMEWORK SUPPORTING AUTONOMOUS RUNTIME PARTIAL RECONFIGURATION.
Creator: Tan, Heng, DeMara, Ronald, University of Central Florida
Abstract / Description: Partial reconfiguration is a unique capability provided by several Field Programmable Gate Array (FPGA) vendors recently, which involves altering part of the programmed design within an SRAM-based FPGA at run-time. In this dissertation, a Multilayer Runtime Reconfiguration Architecture (MRRA) is developed, evaluated, and refined for Autonomous Runtime Partial Reconfiguration of FPGA devices. Under the proposed MRRA paradigm, FPGA configurations can be manipulated at runtime using on-chip...
Show morePartial reconfiguration is a unique capability provided by several Field Programmable Gate Array (FPGA) vendors recently, which involves altering part of the programmed design within an SRAM-based FPGA at run-time. In this dissertation, a Multilayer Runtime Reconfiguration Architecture (MRRA) is developed, evaluated, and refined for Autonomous Runtime Partial Reconfiguration of FPGA devices. Under the proposed MRRA paradigm, FPGA configurations can be manipulated at runtime using on-chip resources. Operations are partitioned into Logic, Translation, and Reconfiguration layers along with a standardized set of Application Programming Interfaces (APIs). At each level, resource details are encapsulated and managed for efficiency and portability during operation. An MRRA mapping theory is developed to link the general logic function and area allocation information to the device related physical configuration level data by using mathematical data structure and physical constraints. In certain scenarios, configuration bit stream data can be read and modified directly for fast operations, relying on the use of similar logic functions and common interconnection resources for communication. A corresponding logic control flow is also developed to make the entire process autonomous. Several prototype MRRA systems are developed on a Xilinx Virtex II Pro platform. The Virtex II Pro on-chip PowerPC core and block RAM are employed to manage control operations while multiple physical interfaces establish and supplement autonomous reconfiguration capabilities. Area, speed and power optimization techniques are developed based on the developed Xilinx prototype. Evaluations and analysis of these prototype and techniques are performed on a number of benchmark and hashing algorithm case studies. The results indicate that based on a variety of test benches, up to 70% reduction in the resource utilization, up to 50% improvement in power consumption, and up to 10 times increase in run-time performance are achieved using the developed architecture and approaches compared with Xilinx baseline reconfiguration flow. Finally, a Genetic Algorithm (GA) for a FPGA fault tolerance case study is evaluated as a ultimate high-level application running on this architecture. It demonstrated that this is a hardware and software infrastructure that enables an FPGA to dynamically reconfigure itself efficiently under the control of a soft microprocessor core that is instantiated within the FPGA fabric. Such a system contributes to the observed benefits of intelligent control, fast reconfiguration, and low overhead.
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Date Issued: 2007
Identifier: CFE0001933, ucf:47448
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0001933

Title: Human-Robot Interaction For Multi-Robot Systems.
Creator: Lewis, Bennie, Sukthankar, Gita, Hughes, Charles, Laviola II, Joseph, Boloni, Ladislau, Hancock, Peter, University of Central Florida
Abstract / Description: Designing an effective human-robot interaction paradigm is particularly important for complex tasks such as multi robot manipulation that require the human and robot to work together in a tightly coupled fashion. Although increasing the number of robots can expand the area that therobots can cover within a bounded period of time, a poor human-robot interface will ultimately compromise the performance of the team of robots. However, introducing a human operator to the team of robots, does not...
Show moreDesigning an effective human-robot interaction paradigm is particularly important for complex tasks such as multi robot manipulation that require the human and robot to work together in a tightly coupled fashion. Although increasing the number of robots can expand the area that therobots can cover within a bounded period of time, a poor human-robot interface will ultimately compromise the performance of the team of robots. However, introducing a human operator to the team of robots, does not automatically improve performance due to the difficulty of teleoperating mobile robots with manipulators. The human operator's concentration is divided not only amongmultiple robots but also between controlling each robot's base and arm. This complexity substantially increases the potential neglect time, since the operator's inability to effectively attend to each robot during a critical phase of the task leads to a significant degradation in task performance.There are several proven paradigms for increasing the efficacy of human-robot interaction: 1) multimodal interfaces in which the user controls the robots using voice and gesture; 2) configurable interfaces which allow the user to create new commands by demonstrating them; 3) adaptive interfaceswhich reduce the operator's workload as necessary through increasing robot autonomy. This dissertation presents an evaluation of the relative benefits of different types of user interfaces for multi-robot systems composed of robots with wheeled bases and three degree of freedom arms. It describes a design for constructing low-cost multi-robot manipulation systems from off the shelfparts.User expertise was measured along three axes (navigation, manipulation, and coordination), and participants who performed above threshold on two out of three dimensions on a calibration task were rated as expert. Our experiments reveal that the relative expertise of the user was the key determinant of the best performing interface paradigm for that user, indicating that good user modeling is essential for designing a human-robot interaction system that will be used for an extended period of time. The contributions of the dissertation include: 1) a model for detecting operator distraction from robot motion trajectories; 2) adjustable autonomy paradigms for reducing operator workload; 3) a method for creating coordinated multi-robot behaviors from demonstrations with a single robot; 4) a user modeling approach for identifying expert-novice differences from short teleoperation traces.
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Date Issued: 2014
Identifier: CFE0005198, ucf:50613
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0005198

Title: PERCEPTION OF CUTENESS AND BEAUTY.
Creator: Jones, Danielle, Poindexter, Carla, University of Central Florida
Abstract / Description: Upbringing and psychological make-up inspire individual norms for beauty and cuteness. The mannerist approach in my work is a product of the figural liberties found in cartooning, illustration and art history. By altering facial and bodily features, I relate the proportions of an infant to cuteness and innocence. However, I tailor the photographs to empower the subjects all the while mirroring trends in contemporary pop culture. I'm interested in themes of everyday life, vitality and...
Show moreUpbringing and psychological make-up inspire individual norms for beauty and cuteness. The mannerist approach in my work is a product of the figural liberties found in cartooning, illustration and art history. By altering facial and bodily features, I relate the proportions of an infant to cuteness and innocence. However, I tailor the photographs to empower the subjects all the while mirroring trends in contemporary pop culture. I'm interested in themes of everyday life, vitality and emotion placed in obscure, imaginary or exaggerated venues. I fictionalize subjects of my reality to compel viewers to identify with and fancy emotions, circumstances, moods and relationships. The intent is to amplify, yet be truer to their existence and idiosyncrasies through figural adaptations.
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Date Issued: 2009
Identifier: CFE0002538, ucf:47637
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0002538

Title: Real People Acting Out Interpersonal Issues With Paper Representations.
Creator: Dufner, Gary, Poindexter, Carla, Raimundi-Ortiz, Wanda, Price, Mark, University of Central Florida
Abstract / Description: In this thesis body of work, I have interacted and collaborated with five friends to create images exploring human relationships. The subject matter illustrates my friends and myself acting out interpersonal issues with paper representations of one another. It has been my aim to represent my imagery in a campy thematic way. I include a discussion of the images in my body of work from both my perspective and the perspective of my models. The figurative paper images (")stand in(") as...
Show moreIn this thesis body of work, I have interacted and collaborated with five friends to create images exploring human relationships. The subject matter illustrates my friends and myself acting out interpersonal issues with paper representations of one another. It has been my aim to represent my imagery in a campy thematic way. I include a discussion of the images in my body of work from both my perspective and the perspective of my models. The figurative paper images (")stand in(") as representatives of the genders of their subjects.I have explored multiple points of view, constructing, reconstructing and deconstructing complex compositions; experimenting with a variety of focal points; and I have increased my knowledge of lighting and color effects through digital manipulation.
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Date Issued: 2015
Identifier: CFE0005607, ucf:52868
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0005607

Title: The Impact of Elementary Mathematics Workshops on Mathematics Knowledge for Parenting (MKP) and Beliefs About Learning Mathematics.
Creator: Eisenreich, Heidi, Dixon, Juli, Ortiz, Enrique, Andreasen, Janet, Brooks, Lisa, Hahs-Vaughn, Debbie, University of Central Florida
Abstract / Description: The purpose of this study was to investigate the extent to which parents of first, second, and third grade students who attended a two-day workshop on mathematics strategies differed on average and over time, as compared to parents who did not attend the workshops. The following areas were measured: mathematics content knowledge, beliefs about learning mathematics, ability to identify correct student responses regarding mathematics, ability to identify student errors in solving mathematics...
Show moreThe purpose of this study was to investigate the extent to which parents of first, second, and third grade students who attended a two-day workshop on mathematics strategies differed on average and over time, as compared to parents who did not attend the workshops. The following areas were measured: mathematics content knowledge, beliefs about learning mathematics, ability to identify correct student responses regarding mathematics, ability to identify student errors in solving mathematics problems, methods used to solve problems, and comfort level with manipulatives.
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Date Issued: 2016
Identifier: CFE0006101, ucf:52877
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0006101

manipulatives (4)	+ -
mathematics (3)	+ -
painting (2)	+ -
photography (2)	+ -
Amusing Ourselves to Death (1)	+ -

Analysis of manipulators (1)	+ -
Analytical solution (1)	+ -
Arachnids (1)	+ -
Arnold Schwarzenegger (1)	+ -
Assistive Robotics (1)	+ -
Autonomous (1)	+ -
Basic Instinct (1)	+ -
Ben-Day dots (1)	+ -
Bill Hicks (1)	+ -
Bimetallic Nanoparticles (1)	+ -
Bio-inspired motion strategies (1)	+ -
Biofluids (1)	+ -
Bitstream Manipulation (1)	+ -
COMSOL (1)	+ -
Caberbe Joseph (1)	+ -
Casper Van Dien (1)	+ -
Cell encapsulation (1)	+ -
Closed-form solutions (1)	+ -
Cubism (1)	+ -
David Cronenberg (1)	+ -
Denise Richards (1)	+ -
Density Functional Theory (1)	+ -
Diffusion (1)	+ -
Discipline and Punish (1)	+ -
Droplet Manipulation (1)	+ -

ETD Collection (19)	+ -
Honors Collection (2)	+ -

University of Central Florida (21)	+ -
Dixon, Juli (3)	+ -
Andreasen, Janet (2)	+ -
Boloni, Ladislau (2)	+ -
Defterli, Sinem (2)	+ -

Dieker, Lisa (2)	+ -
Kumar, Ranganathan (2)	+ -
Lin, Kuo-Chi (2)	+ -
Poindexter, Carla (2)	+ -
Song, Sang-Eun (2)	+ -
Xu, Yunjun (2)	+ -
Zheng, Qipeng (2)	+ -
Abelson, Jesse (1)	+ -
Basham, James (1)	+ -
Behal, Aman (1)	+ -
Brooks, Lisa (1)	+ -
Cho, Hyoung Jin (1)	+ -
Davanlou, Ashkan (1)	+ -
DeMara, Ronald (1)	+ -
Deng, Weiwei (1)	+ -
Dufner, Gary (1)	+ -
Eisenreich, Heidi (1)	+ -
Gresham, Regina (1)	+ -
Hahs-Vaughn, Debbie (1)	+ -
Hancock, Peter (1)	+ -
Haralambous, Michael (1)	+ -
Haxton, David (1)	+ -
Hoffman, Elizabeth (1)	+ -
Hughes, Charles (1)	+ -
Janz, Bruce (1)	+ -

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