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- Title
- The influence of trait anxiety on information processing: An elaboration likelihood study.
- Creator
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Appelbaum, Michael, Miller, Ann, Weger, Harry, Rubenking, Bridget, University of Central Florida
- Abstract / Description
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This study explored the influence of trait anxiety on information processing in persuasive situations, and investigated cognitive load as a mediator of this relationship. The research presented was based off DeBono and McDermott's (1994) framework for exploring trait anxiety and persuasion. The theoretical lens used to explore information processing, the elaboration likelihood model (Petty (&) Cacioppo, 1986) posits that motivation and ability are necessary components to elaborate on a...
Show moreThis study explored the influence of trait anxiety on information processing in persuasive situations, and investigated cognitive load as a mediator of this relationship. The research presented was based off DeBono and McDermott's (1994) framework for exploring trait anxiety and persuasion. The theoretical lens used to explore information processing, the elaboration likelihood model (Petty (&) Cacioppo, 1986) posits that motivation and ability are necessary components to elaborate on a message. However, very little research has addressed ability variables like trait anxiety. I predicted that students high in trait anxiety would be persuaded by the attractiveness of the source (peripherally) whereas students low in trait anxiety would be persuaded by the strength of the arguments presented (centrally).Undergraduate students were asked to view a picture of a policy presenter and listen to a recording of the student's proposed policy statement. After listening to the recording participants wrote down their thoughts during the presentation and were tested on their ability to recall the arguments presented. They then completed a few scale items assessing their attitudes toward the policy as well as questions to maintain the cover story.Findings showed no difference in processing between low and high trait anxious individuals. However, there was a significant effect of anxiety on attitudes. Additionally, cognitive load was not found to be a mediator of the relationship between anxiety and attitudes.
Show less - Date Issued
- 2015
- Identifier
- CFE0005572, ucf:50262
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0005572
- Title
- Mathematical Modeling of Carbon Removal in the A-Stage Activated Sludge System.
- Creator
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Nogaj, Thomas, Randall, Andrew, Duranceau, Steven, Chopra, Manoj, Jimenez, Jose, University of Central Florida
- Abstract / Description
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This research developed a dynamic activated sludge model (ASM) to better describe the overall removal of organic substrate, quantified as chemical oxygen demand (COD), from A-stage high rate activated sludge (HRAS) systems. This dynamic computer model is based on a modified ASM1 (Henze et al., 2000) model. It was determined early in the project that influent soluble COD, which is normally represented by a single state variable in ASM1, had to be subdivided into two state variables (SBs and...
Show moreThis research developed a dynamic activated sludge model (ASM) to better describe the overall removal of organic substrate, quantified as chemical oxygen demand (COD), from A-stage high rate activated sludge (HRAS) systems. This dynamic computer model is based on a modified ASM1 (Henze et al., 2000) model. It was determined early in the project that influent soluble COD, which is normally represented by a single state variable in ASM1, had to be subdivided into two state variables (SBs and SBf, or slow and fast fractions) to simulate the performance of A-stage systems. Also, the addition of state variables differentiating colloidal COD from suspended COD was necessary due to short hydraulic residence times in A-stage systems which do not allow for complete enmeshment and bioflocculation of these particles as occurs in conventional activated sludge systems (which have longer solid retention times and hydraulic retention times). It was necessary to add several processes (both stoichiometry and kinetic equations) to the original ASM1 model including heterotrophic growth on both soluble substrate fractions and bioflocculation of colloidal solids. How to properly quantify heterotrophic growth on SBs and SBf resulted in two separate approaches with respect to process kinetic equations. In one approach the SBf was metabolized preferentially over SBs which was only utilized when SBf was not available. This is referred to as the Diauxic Model. In the other approach SBf and SBs were metabolized simultaneously, and this is referred to as the Dual Substrate Model. The Dual Substrate Model calibrated slightly better than the Diauxic Model for one of the two available pilot studies data sets (the other set was used for model verification). The Dual Substrate A-stage model was used to describe the effects of varying specific operating parameters including solids retention time (SRT), dissolved oxygen (DO), influent COD and temperature on the effluent COD:N ratio. The effluent COD:N ratio target was based on its suitability for a downstream nitrite shunt (i.e. nitritation/denitritation) process. In the downstream process the goal is to eliminate nitrite oxidizing bacteria (NOB) from the reactor while selecting for ammonia oxidizing bacteria (AOB). The results showed that a low SRT ((<)0.25 d) can produce high effluent substrates (SB and CB), and elevated COD:N ratios consistent with NOB out-selection downstream, the HRAS model was able to predict the measured higher fraction of CB in the A-stage effluent at lower SRTs and DO concentrations, and to achieve the benefits of operating an A-stage process, while maintaining an effluent COD:N ratio suitable for a downstream nitritation/denitritation process, an A-stage SRT in the range of 0.1 to 0.25 d should be maintained.This research also included an analysis of A-stage pilot data using stoichiometry to determine the bio-products formed from soluble substrate removed in an A-stage reactor. The results were used to further refine the process components and stoichiometric parameters to be used in the A-stage dynamic computer model, which includes process mechanisms for flocculation and enmeshment of particulate and colloidal substrate, hydrolysis, production of extracellular polymeric substances (EPS) and storage of soluble biodegradable substrate. Analysis of pilot data and simulations with the dynamic computer model implied (indirectly) that storage products were probably significant in A-stage COD removal.
Show less - Date Issued
- 2015
- Identifier
- CFE0005677, ucf:50161
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0005677
- Title
- Resource allocation and load-shedding policies based on Markov decision processes for renewable energy generation and storage.
- Creator
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Jimenez, Edwards, Atia, George, Richie, Samuel, Pazour, Jennifer, University of Central Florida
- Abstract / Description
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In modern power systems, renewable energy has become an increasingly popular form of energy generation as a result of all the rules and regulations that are being implemented towards achieving clean energy worldwide. However, clean energy can have drawbacks in several forms. Wind energy, for example can introduce intermittency. In this thesis, we discuss a method to deal with this intermittency. In particular, by shedding some specific amount of load we can avoid a total system breakdown of...
Show moreIn modern power systems, renewable energy has become an increasingly popular form of energy generation as a result of all the rules and regulations that are being implemented towards achieving clean energy worldwide. However, clean energy can have drawbacks in several forms. Wind energy, for example can introduce intermittency. In this thesis, we discuss a method to deal with this intermittency. In particular, by shedding some specific amount of load we can avoid a total system breakdown of the entire power plant. The load shedding method discussed in this thesis utilizes a Markov Decision Process with backward policy iteration. This is based on a probabilistic method that chooses the best load-shedding path that minimizes the expected total cost to ensure no power failure. We compare our results with two control policies, a load-balancing policy and a less-load shedding policy. It is shown that the proposed MDP policy outperforms the other control policies and achieves the minimum total expected cost.
Show less - Date Issued
- 2015
- Identifier
- CFE0005635, ucf:50222
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0005635
- Title
- The Normalization Process of Multimodal Composition: "Unseeing" People of Color in Multimodal Composition Scholarship.
- Creator
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Davis, Yumani, Rios, Gabriela, Roozen, Kevin, Pigg, Stacey, University of Central Florida
- Abstract / Description
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This study attempts to identify normalization cues within multimodal scholarship to highlight moments of (")un-seeing(") multimodal composing practices and theoretical contributions from non-Western traditions. Advocates of this approach to teaching composition understand it as an effective way for incorporating other voices into the curricular structures of composition courses. However, the instructional resources do not include or cite research that does not lend itself easily to dominant...
Show moreThis study attempts to identify normalization cues within multimodal scholarship to highlight moments of (")un-seeing(") multimodal composing practices and theoretical contributions from non-Western traditions. Advocates of this approach to teaching composition understand it as an effective way for incorporating other voices into the curricular structures of composition courses. However, the instructional resources do not include or cite research that does not lend itself easily to dominant views of composing within academia. I assert that academia must go further with how value is assessed. There is research that acknowledges the multiliteracies practices found within subcultures of America, and plenty of work that deems the communicative practices observed in these subcultural communities as valuable. However, it is more than just including and citing scholarship from and about people of color's compositional practices, academia must also employ these ways of knowing and being to fully empower students and utilize the knowledge that the students bring with them to the FYC classroom. The dominant assignment genre in academia is the academic essay. Other dominant methods of communication and transferring scholarship are the journal article, annotated bibliography, proposal, and personal essay. Not to mention the many scholars who have critiqued academia for privileging print literacies, which although may be multimodal, promotes a multimodality of one culture and ideological standpoint. Although the seminal texts from the study offer exceptional multimodal composition research and classroom resources, if we can agree that (")the mission of education is to ensure that all students benefit from learning in ways that allow them to participate fully in public, community, and economic life(") and that literacy pedagogy, essentially what the FYC course offers, (")is expected to play a particularly important role in fulfilling this mission,(") then failing to see the value and utilize the scholarship from and about people of color ensures those that are marginalized continue to be (")un-seen(") and students remain unprepared for the tasks of composing and communicating outside of school (New London Group 60).
Show less - Date Issued
- 2015
- Identifier
- CFE0005779, ucf:50071
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0005779
- Title
- rf power amplifier and oscillator design for reliability and variability.
- Creator
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Chen, Shuyu, Yuan, Jiann-Shiun, Sundaram, Kalpathy, Shen, Zheng, Gong, Xun, Wang, Morgan, University of Central Florida
- Abstract / Description
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CMOS RF circuit design has been an ever-lasting research field. It gained so much attention since RF circuits have high mobility and wide band efficiency, while CMOS technology has the advantage of low cost and better capability of integration. At the same time, IC circuits never stopped scaling down for the recent many decades. Reliability issues with RF circuits have become more and more severe with device scaling down: reliability effects such as gate oxide break down, hot carrier...
Show moreCMOS RF circuit design has been an ever-lasting research field. It gained so much attention since RF circuits have high mobility and wide band efficiency, while CMOS technology has the advantage of low cost and better capability of integration. At the same time, IC circuits never stopped scaling down for the recent many decades. Reliability issues with RF circuits have become more and more severe with device scaling down: reliability effects such as gate oxide break down, hot carrier injection, negative bias temperature instability, have been amplified as the device size shrinks. Process variability issues also become more predominant as the feature size decreases. With these insights provided, reliability and variability evaluations on typical RF circuits and possible compensation techniques are highly desirable.In this work, a class E power amplifier is designed and laid out using TSMC 0.18 (&)#181;m RF technology and the chip was fabricated. Oxide stress and hot electron tests were carried out at elevated supply voltage, fresh measurement results were compared with different stress conditions after 10 hours. Test results matched very well with mixed mode circuit simulations, proved that hot carrier effects degrades PA performances like output power, power efficiency, etc. Self- heating effects were examined on a class AB power amplifier since PA has high power operations. Device temperature simulation was done both in DC and mixed mode level. Different gate biasing techniques were analyzed and their abilities to compensate output power were compared. A simple gate biasing circuit turned out to be efficient to compensate self-heating effects under different localized heating situations. Process variation was studied on a classic Colpitts oscillator using Monte-Carlo simulation. Phase noise was examined since it is a key parameter in oscillator. Phase noise was modeled using analytical equations and supported by good match between MATLAB results and ADS simulation. An adaptive body biasing circuit was proposed to eliminate process variation. Results from probability density function simulation demonstrated its capability to relieve process variation on phase noise. Standard deviation of phase noise with adaptive body bias is much less than the one without compensation. Finally, a robust, adaptive design technique using PLL as on-chip sensor to reduce Process, Voltage, Temperature (P.V.T.) variations and other aging effects on RF PA was evaluated. The frequency and phase of ring oscillator need to be adjusted to follow the frequency and phase of input in PLL no matter how the working condition varies. As a result, the control signal of ring oscillator has to fluctuate according to the working condition, reflecting the P.V.T changes. RF circuits suffer from similar P.V.T. variations. The control signal of PLL is introduced to RF circuits and converted to the adaptive tuning voltage for substrate bias. Simulation results illustrate that the PA output power under different variations is more flat than the one with no compensation. Analytical equations show good support to what has been observed.
Show less - Date Issued
- 2013
- Identifier
- CFE0004664, ucf:49894
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0004664
- Title
- Mathematical and Computational Methods for Freeform Optical Shape Description.
- Creator
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Kaya, Ilhan, Foroosh, Hassan, Rolland, Jannick, Turgut, Damla, Thompson, Kevin, Ilegbusi, Olusegun, University of Central Florida
- Abstract / Description
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Slow-servo single-point diamond turning as well as advances in computer controlled small lap polishing enable the fabrication of freeform optics, specifically, optical surfaces for imaging applications that are not rotationally symmetric. Freeform optical elements will have a profound importance in the future of optical technology. Orthogonal polynomials added onto conic sections have been extensively used to describe optical surface shapes. The optical testing industry has chosen to...
Show moreSlow-servo single-point diamond turning as well as advances in computer controlled small lap polishing enable the fabrication of freeform optics, specifically, optical surfaces for imaging applications that are not rotationally symmetric. Freeform optical elements will have a profound importance in the future of optical technology. Orthogonal polynomials added onto conic sections have been extensively used to describe optical surface shapes. The optical testing industry has chosen to represent the departure of a wavefront under test from a reference sphere in terms of orthogonal ?-polynomials, specifically Zernike polynomials. Various forms of polynomials for describing freeform optical surfaces may be considered, however, both in optical design and in support of fabrication. More recently, radial basis functions were also investigated for optical shape description. In the application of orthogonal ?-polynomials to optical freeform shape description, there are important limitations, such as the number of terms required as well as edge-ringing and ill-conditioning in representing the surface with the accuracy demanded by most stringent optics applications. The first part of this dissertation focuses upon describing freeform optical surfaces with ? polynomials and shows their limitations when including higher orders together with possible remedies. We show that a possible remedy is to use edge clustered-fitting grids. Provided different grid types, we furthermore compared the efficacy of using different types of ? polynomials, namely Zernike and gradient orthogonal Q polynomials. In the second part of this thesis, a local, efficient and accurate hybrid method is developed in order to greatly reduce the order of polynomial terms required to achieve higher level of accuracy in freeform shape description that were shown to require thousands of terms including many higher order terms under prior art. This comes at the expense of multiple sub-apertures, and as such computational methods may leverage parallel processing. This new method combines the assets of both radial basis functions and orthogonal phi-polynomials for freeform shape description and is uniquely applicable across any aperture shape due to its locality and stitching principles. Finally in this thesis, in order to comprehend the possible advantages of parallel computing for optical surface descriptions, the benefits of making an effective use of impressive computational power offered by multi-core platforms for the computation of ?-polynomials are investigated. The ?-polynomials, specifically Zernike and gradient orthogonal Q-polynomials, are implemented with a set of recurrence based parallel algorithms on Graphics Processing Units (GPUs). The results show that more than an order of magnitude speedup is possible in the computation of ?-polynomials over a sequential implementation if the recurrence based parallel algorithms are adopted.
Show less - Date Issued
- 2013
- Identifier
- CFE0005012, ucf:49993
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0005012
- Title
- Vision-Based Sensing and Optimal Control for Low-Cost and Small Satellite Platforms.
- Creator
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Sease, Bradley, Xu, Yunjun, Lin, Kuo-Chi, Bradley, Eric, University of Central Florida
- Abstract / Description
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Current trends in spacecraft are leading to smaller, more inexpensive options whenever possible. This shift has been primarily pursued for the opportunity to open a new frontier for technologies with a small financial obligation. Limited power, processing, pointing, and communication capabilities are all common issues which must be considered when miniaturizing systems and implementing low-cost components. This thesis addresses some of these concerns by applying two methods, in attitude...
Show moreCurrent trends in spacecraft are leading to smaller, more inexpensive options whenever possible. This shift has been primarily pursued for the opportunity to open a new frontier for technologies with a small financial obligation. Limited power, processing, pointing, and communication capabilities are all common issues which must be considered when miniaturizing systems and implementing low-cost components. This thesis addresses some of these concerns by applying two methods, in attitude estimation and control. Additionally, these methods are not restricted to only small, inexpensive satellites, but offer a benefit to large-scale spacecraft as well.First, star cameras are examined for the tendency to generate streaked star images during maneuvers. This issue also comes into play when pointing capabilities and camera hardware quality are low, as is often the case in small, budget-constrained spacecraft. When pointing capabilities are low, small residual velocities can cause movement of the stars in the focal plane during an exposure, causing them to streak across the image. Additionally, if the camera quality is low, longer exposures may be required to gather sufficient light from a star, further contributing to streaking. Rather than improving the pointing or hardware directly, an algorithm is presented to retrieve and utilize the endpoints of streaked stars to provide feedback where traditional methods do not. This allows precise attitude and angular rate estimates to be derived from an image which, with traditional methods, would return large attitude and rate error. Simulation results are presented which demonstrate endpoint error of approximately half a pixel and rate estimates within 2% of the true angular velocity. Three methods are also considered to remove overlapping star streaks and resident space objects from images to improve performance of both attitude and rate estimates. Results from a large-scale Monte Carlo simulation are presented in order to characterize the performance of the method.Additionally, a rapid optimal attitude guidance method is experimentally validated in a ground-based, pico-scale satellite test bed. Fast slewing performance is demonstrated for an incremental step maneuver with low average power consumption. Though the focus of this thesis is primarily on increasing the capabilities of small, inexpensive spacecraft, the methods discussed have the potential to increase the capabilities of current and future large-scale missions as well.
Show less - Date Issued
- 2013
- Identifier
- CFE0005249, ucf:50603
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0005249
- Title
- COMMISSIONING OF AN ARC-MELTING / VACUUM QUENCH FURNACE FACILITY FOR FABRICATION OF NI-TI-FE SHAPE MEMORY ALLOYS, AND THEIR CHARACTERIZATION.
- Creator
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Singh, Jagat, Vaidyanathan, Raj, University of Central Florida
- Abstract / Description
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Shape memory alloys when deformed can produce strains as high as 8%. Heating results in a phase transformation and associated recovery of all the accumulated strain, a phenomenon known as shape memory. This strain recovery can occur against large forces, resulting in their use as actuators. The goal of this project is to lower the operating temperature range of shape memory alloys in order for them to be used in cryogenic switches, seals, valves, fluid-line repair and self-healing gaskets for...
Show moreShape memory alloys when deformed can produce strains as high as 8%. Heating results in a phase transformation and associated recovery of all the accumulated strain, a phenomenon known as shape memory. This strain recovery can occur against large forces, resulting in their use as actuators. The goal of this project is to lower the operating temperature range of shape memory alloys in order for them to be used in cryogenic switches, seals, valves, fluid-line repair and self-healing gaskets for space related technologies. The Ni-Ti-Fe alloy system, previously used in Grumman F-14 aircrafts and activated at 120 K, is further developed through arc-melting a range of compositions and subsequent thermo-mechanical processing. A controlled atmosphere arc-melting facility and vertical vacuum quench furnace facility was commissioned to fabricate these alloys. The facility can create a vacuum of 10-7 Torr and heat treat samples up to 977 °C. High purity powders of Ni, Ti and Fe in varying ratios were mixed and arc-melted into small buttons weighing 0.010 kg to 0.025 kg. The alloys were subjected to solutionizing and aging treatments. A combination of rolling, electro-discharge machining and low-speed cutting techniques were used to produce strips. Successful rolling experiments highlighted the workability of these alloys. The shape memory effect was successfully demonstrated at liquid nitrogen temperatures through a constrained recovery experiment that generated stresses of over 40 MPa. Differential scanning calorimetry (DSC) and a dilatometry setup was used to characterize the fabricated materials and determine relationships between composition, thermo-mechanical processing parameters and transformation temperatures.
Show less - Date Issued
- 2004
- Identifier
- CFE0000308, ucf:46320
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0000308
- Title
- PORTRAYING POINTILLISM: AN ACTRESS'S JOURNEY THROUGH POINTILLISM TO DEFINE THE ROLE OF DOT IN SONDHEIM AND LAPINE'S MUSICAL SUNDAY IN THE PARK WITH GEORGE.
- Creator
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Staffel, Chris, Tollefson, Kristina, University of Central Florida
- Abstract / Description
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Upon receiving a role, an actor must research the major themes, concepts, and relationships associated with the play, its collaborators, and the character they are to portray. Only by layering this combination of research and analysis to the rehearsal process and performances in a detailed format can an actor cohesively transform the learned knowledge from the performer's training and research to a finished product on stage. Many forms of art are created using a similar process. This...
Show moreUpon receiving a role, an actor must research the major themes, concepts, and relationships associated with the play, its collaborators, and the character they are to portray. Only by layering this combination of research and analysis to the rehearsal process and performances in a detailed format can an actor cohesively transform the learned knowledge from the performer's training and research to a finished product on stage. Many forms of art are created using a similar process. This thesis will explore the similarities between the Post-Impressionist technique of pointillism and the actor's process in developing a role. Upon observing the basic process of each technique, one can conclude that the method of consistently adding many specific elements eventually creates a finished product whether it is in the form of a painting on a canvas or a performance on a stage. By paralleling these two artistic techniques, a new contribution to musical theatre is made by presenting a fresh outlook for performers in their approach to creating roles. Research on pointillism and George Seurat's painting technique when interwoven with Stephen Sondheim's techniques in music theory (specifically the examples derived from the score of Sunday in the Park with George), and compared to my technique and process as the actor playing the role of Dot in the University of Central Florida Conservatory Theatre's 2006 Spring production of Sunday in the Park with George, demonstrates how the theories of pointillism and the actor's process are clearly comparable and arguably inseparable.
Show less - Date Issued
- 2006
- Identifier
- CFE0001380, ucf:47009
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0001380
- Title
- SIGNAL PROCESSING OF AN ECG SIGNALIN THE PRESENCE OF A STRONG STATIC MAGNETIC FIELD.
- Creator
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Gupta, Aditya, Weeks, Arthur, University of Central Florida
- Abstract / Description
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This dissertation addresses the problem of elevation of the T wave of an electrocardiogram (ECG) signal in the magnetic resonance imaging (MRI). In the MRI, due to the strong static magnetic field the interaction of the blood flow with this strong magnetic field induces a voltage in the body. This voltage appears as a superimposition at the locus of the T wave of the ECG signal. This looses important information required by the doctors to interpret the ST segment of the ECG and detect...
Show moreThis dissertation addresses the problem of elevation of the T wave of an electrocardiogram (ECG) signal in the magnetic resonance imaging (MRI). In the MRI, due to the strong static magnetic field the interaction of the blood flow with this strong magnetic field induces a voltage in the body. This voltage appears as a superimposition at the locus of the T wave of the ECG signal. This looses important information required by the doctors to interpret the ST segment of the ECG and detect diseases such as myocardial infarction. This dissertation aims at finding a solution to the problem of elevation of the T wave of an ECG signal in the MRI. The first step is to simulate the entire situation and obtain the magnetic field dependent T wave elevation. This is achieved by building a model of the aorta and simulating the blood flow in it. This model is then subjected to a static magnetic field and the surface potential on the thorax is measured to observe the T wave elevation. The various parameters on which the T wave elevation is dependent are then analyzed. Different approaches are used to reduce this T wave elevation problem. The direct approach aims at computing the magnitude of T wave elevation using magneto-hydro-dynamic equations. The indirect approach uses digital signal processing tools like the least mean square adaptive filter to remove the T wave elevation and obtain artifact free ECG signal in the MRI. Excellent results are obtained from the simulation model. The model perfectly simulates the ECG signal in the MRI at all the 12 leads of the ECG. These results are compared with ECG signals measured in the MRI. A simulation package is developed in MATLAB based on the simulation model. This package is a graphical user interface allowing the user to change the strength of magnetic field, the radius of the aorta and the orientation of the aorta with respect to the heart and observe the ECG signals with the elevation at the 12 leads of the ECG. Also the artifacts introduced due to the magnetic field can be removed by the least mean square adaptive filter. The filter adapts the ECG signal in the MRI to the ECG signal of the patient outside the MRI. Before the adaptation, the heart rate of the ECG outside the MRI is matched to the ECG in the MRI by interpolation or decimation. The adaptive filter works excellently to remove the T wave artifacts. When the cardiac output of the patient changes, the simulation model is used along with the adaptive filter to obtain the artifact free ECG signal.
Show less - Date Issued
- 2007
- Identifier
- CFE0001857, ucf:47389
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0001857
- Title
- CENTRAL AUDITORY PROCESSING DISORDER: A LITERATURE REVIEW ON INTER-DISCIPLINARY MANAGEMENT, INTERVENTION, AND IMPLICATIONS FOR EDUCATORS.
- Creator
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Patrusky, Lauren, Wenzel, Dr. Taylar, University of Central Florida
- Abstract / Description
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Clinical Questions: What top-down and bottom-up interventions across the psychology, audiology, educational, and speech language pathology domains are most effective for children and adolescents with Central Auditory Processing Disorder (CAPD)? What considerations for planning research and intervention might be offered to a classroom teacher to further support students diagnosed with CAPD, especially in relation to the Multi-Tiered System of Supports (MTSS), formerly known as Response to...
Show moreClinical Questions: What top-down and bottom-up interventions across the psychology, audiology, educational, and speech language pathology domains are most effective for children and adolescents with Central Auditory Processing Disorder (CAPD)? What considerations for planning research and intervention might be offered to a classroom teacher to further support students diagnosed with CAPD, especially in relation to the Multi-Tiered System of Supports (MTSS), formerly known as Response to Intervention (RTI)? Method: Inter-Disciplinary Literature Review Study Sources: PsycInfo, Linguistics and Language Behavior Abstracts, ProQuest, International Journal of Audiology, American-Speech-Language Hearing Association, Journal of Neurotherapy, Medline-Esbcohost, ERIC Ebscohost, Professional Development Collection Education, and What Works Clearinghouse Number of Included Studies: 16 Age Range: 2-13 years Primary Results: 1) Phonological awareness training was the primary reading educational construct found among the included interventions in this literature review. 2) Most CAPD studies employed a combination of both bottom-up and top-down treatments in intervention. This finding may possibly indicate that in order for a CAPD intervention to be even more beneficial to the student, both bottom-up and top-down treatments should be considered and incorporated in relation to the student's individualized needs. Conclusions: Results confirmed very little research and few intervention implications on CAPD students within the educational research discipline, including special education. Search results primarily included methods to improve listening in the classroom environment, but did not specifically mention intervention in relation to CAPD and its implications. Results also confirmed that a multi-disciplinary effort is needed to provide clinical decision and effective intervention for the CAPD population.
Show less - Date Issued
- 2013
- Identifier
- CFH0004389, ucf:45014
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFH0004389
- Title
- Appropriate Adjective: Executive Authority and the Classification of Enemy Combatants.
- Creator
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Davis, Taraleigh, Merriam, Eric, Bledsoe, Robert, Edwards, Barry, University of Central Florida
- Abstract / Description
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Is the term enemy combatant an established legal category of persons under international law? Has the President exceeded his constitutional authority in classifying United States citizens who are suspected terrorists as enemy combatants? In 2018 a U.S. citizen was released after being held for 13 months as an enemy combatant. He was detained without being charged with a crime and without the ability to challenge the legality of his detention. This thesis serves two purposes. First, it will...
Show moreIs the term enemy combatant an established legal category of persons under international law? Has the President exceeded his constitutional authority in classifying United States citizens who are suspected terrorists as enemy combatants? In 2018 a U.S. citizen was released after being held for 13 months as an enemy combatant. He was detained without being charged with a crime and without the ability to challenge the legality of his detention. This thesis serves two purposes. First, it will seek to trace the history of the term enemy combatant and highlight the evolution of its use by the executive branch. This thesis then examines whether the executive has exceeded his constitutional authority to classify a United States citizen as an enemy combatant. While most of the literature focuses on the treatment and detention of enemy combatants, existing scholarship largely overlooks the issue of authority to classify enemy combatants. This thesis will argue that the executive is overstepping the boundaries of its presidential power when the executive branch creates the criteria (a legislative function) for enemy combatants and applies the criteria in the classification of enemy combatants (a judicial function). This qualitative study will use normative legal research focusing on the principles of the law in classifying a suspected terrorist as an enemy combatant as well as the legal history of the term. The analysis of the legal history of the term enemy combatant will be completed by content analysis using Nvivo 12 software of various government documents as well as case studies of enemy combatant cases.
Show less - Date Issued
- 2019
- Identifier
- CFE0007448, ucf:52703
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0007448
- Title
- Video categorization using semantics and semiotics.
- Creator
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Rasheed, Zeeshan, Shah, Mubarak, Engineering and Computer Science
- Abstract / Description
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University of Central Florida College of Engineering Thesis; There is a great need to automatically segment, categorize, and annotate video data, and to develop efficient tools for browsing and searching. We believe that the categorization of videos can be achieved by exploring the concepts and meanings of the videos. This task requires bridging the gap between low-level content and high-level concepts (or semantics). Once a relationship is established between the low-level computable...
Show moreUniversity of Central Florida College of Engineering Thesis; There is a great need to automatically segment, categorize, and annotate video data, and to develop efficient tools for browsing and searching. We believe that the categorization of videos can be achieved by exploring the concepts and meanings of the videos. This task requires bridging the gap between low-level content and high-level concepts (or semantics). Once a relationship is established between the low-level computable features of the video and its semantics, .the user would be able to navigate through videos through the use of concepts and ideas (for example, a user could extract only those scenes in an action film that actually contain fights) rat her than sequentially browsing the whole video. However, this relationship must follow the norms of human perception and abide by the rules that are most often followed by the creators (directors) of these videos. These rules are called film grammar in video production literature. Like any natural language, this grammar has several dialects, but it has been acknowledged to be universal. Therefore, the knowledge of film grammar can be exploited effectively for the understanding of films. To interpret an idea using the grammar, we need to first understand the symbols, as in natural languages, and second, understand the rules of combination of these symbols to represent concepts. In order to develop algorithms that exploit this film grammar, it is necessary to relate the symbols of the grammar to computable video features.
Show less - Date Issued
- 2003
- Identifier
- CFR0001717, ucf:52920
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFR0001717
- Title
- Larger-first partial parsing.
- Creator
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Van Delden, Sebastian Alexander, Gomez, Fernando, Engineering and Computer Science
- Abstract / Description
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University of Central Florida College of Engineering Thesis; Larger-first partial parsing is a primarily top-down approach to partial parsing that is opposite to current easy-first, or primarily bottom-up, strategies. A rich partial tree structure is captured by an algorithm that assigns a hierarchy of structural tags to each of the input tokens in a sentence. Part-of-speech tags are first assigned to the words in a sentence by a part-of-speech tagger. A cascade of Deterministic Finite State...
Show moreUniversity of Central Florida College of Engineering Thesis; Larger-first partial parsing is a primarily top-down approach to partial parsing that is opposite to current easy-first, or primarily bottom-up, strategies. A rich partial tree structure is captured by an algorithm that assigns a hierarchy of structural tags to each of the input tokens in a sentence. Part-of-speech tags are first assigned to the words in a sentence by a part-of-speech tagger. A cascade of Deterministic Finite State Automata then uses this part-of-speech information to identify syntactic relations primarily ina descending order of their size. The cascade is divided into four specialized sections: (1) a Comma Network, which identifies syntactic relations associated with commas; (2) a Conjunction Network, which partially disambiguates phrasal conjunctions and fully disambiguates clausal conjunctions; (3) a Clause Network, which identifies non-comma-delimited clauses; and (4) a Phrase Network, which identifies the remaining base phrases in the sentence. Each automaton is capable of adding one ore more levels of structural tags to the to the tokens in a sentence. The larger-first approach is compared against a well-known easy-first approach. The results indicate that this larger-first approach is capable of (1) producing a more detailed partial parse than an easy first approach; (2) providing better containment of attachment ambiguity; (3) handling overlapping syntactic relations; and (4) achieving a higher accuracy than the easy-first approach. The automata of each network were developed by an empirical analysis of several sources and are presented here in details.
Show less - Date Issued
- 2003
- Identifier
- CFR0000760, ucf:52932
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFR0000760
- Title
- The effect of carbon nanotube/organic semiconductor interfacial area on the performance of organic transistors.
- Creator
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Kang, Narae, Khondaker, Saiful, Leuenberger, Michael, Zhai, Lei, University of Central Florida
- Abstract / Description
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Organic field-effect transistors (OFETs) have attracted tremendous attention due to their flexibility, transparency, easy processiblity and low cost of fabrication. High-performance OFETs are required for their potential applications in the organic electronic devices such as flexible display, integrated circuit, and radiofrequency identification tags. One of the major limiting factors in fabricating high-performance OFET is the large interfacial barrier between metal electrodes and OSC which...
Show moreOrganic field-effect transistors (OFETs) have attracted tremendous attention due to their flexibility, transparency, easy processiblity and low cost of fabrication. High-performance OFETs are required for their potential applications in the organic electronic devices such as flexible display, integrated circuit, and radiofrequency identification tags. One of the major limiting factors in fabricating high-performance OFET is the large interfacial barrier between metal electrodes and OSC which results in low charge injection from the metal electrodes to OSC. In order to overcome the challenge of low charge injection, carbon nanotubes (CNTs) have been suggested as a promising electrode material for organic electronic devices. In this dissertation, we study the effect of carbon nanotube (CNT) density in CNT electrodes on the performance of organic field effect transistor (OFETs). The devices were fabricated by thermal evaporation of pentacene on the Pd/single walled CNT (SWCNT) electrodes where SWCNTs of different density (0-30/um) were aligned on Pd using dielectrophoresis (DEP) and cut via oxygen plasma etching to keep the length of nanotube short compared to the channel length. From the electronic transport measurements of 40 devices, we show that the average saturation mobility of the devices increased from 0.02 for zero SWCNT to 0.06, 0.13 and 0.19 cm2/Vs for low (1-5 /(&)#181;m), medium (10-15 /(&)#181;m) and high (25-30 /(&)#181;m) SWCNT density in the electrodes, respectively. The increase is three, six and nine times for low, medium and high density SWCNTs in the electrode compared to the devices that did not contain any SWCNT. In addition, the current on-off ratio and on-current of the devices are increased up to 40 times and 20 times with increasing SWCNT density in the electrodes. Our study shows that although a few nanotubes in the electrode can improve the OFET device performance, significant improvement can be achieved by maximizing SWCNT/OSC interfacial area. The improved OFET performance can be explained due to a reduced barrier height of SWCNT/pentacene interface compared to metal/pentacene interface which provides more efficient charge injection pathways with increased SWCNT/pentacene interfacial area.
Show less - Date Issued
- 2012
- Identifier
- CFE0004558, ucf:49252
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0004558
- Title
- THE BORN VERSUS MADE DEBATE: AN EXAMINATION OF COMMUNITY COLLEGE INSTRUCTORS' BELIEFS AND TEACHING PRACTICES.
- Creator
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Hardin, Christina, Gill, Michele, University of Central Florida
- Abstract / Description
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Research on the development of K-12 teachers' beliefs about and approaches to teaching and learning suggests that exposure to professional development programs can lead to the use of conceptual change strategies that engage students as active participants in the learning process rather than on teacher-centered strategies focused on information transfer. However, within the existing literature on the development of teacher beliefs and approaches to teaching and learning there exists a void of...
Show moreResearch on the development of K-12 teachers' beliefs about and approaches to teaching and learning suggests that exposure to professional development programs can lead to the use of conceptual change strategies that engage students as active participants in the learning process rather than on teacher-centered strategies focused on information transfer. However, within the existing literature on the development of teacher beliefs and approaches to teaching and learning there exists a void of information pertaining to the development of community college instructors' beliefs and approaches. The purpose of this study was to investigate the relationship between pre-tenure community college instructors' beliefs about teaching and learning, their approaches to the learning process, and the training they receive via a professional development program specifically established to provide training in teaching methods, pedagogy, curriculum, and/ or instruction. Forty community college instructors going through an established three-year tenure process completed a revised version of the Approaches to Teaching Inventory (ATI-R) created by Trigwell and Prosser (1998). Data analysis revealed that there was no difference in the scores of instructors who had participated in the professional development program on teaching and learning and those instructors who had no exposure to courses that focused on teaching and learning. Further, findings suggest that instructors' participation in the courses is not related to their beliefs or teaching approaches. The findings of this study warrant a closer examination of programs designed to provide higher education instructors with training in pedagogy and instruction. Additionally, the findings present an opportunity for professional development programs to improve current practice.
Show less - Date Issued
- 2011
- Identifier
- CFE0003577, ucf:48920
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0003577
- Title
- PRICE DISCOVERY IN THE U.S. BOND MARKETS: TRADING STRATEGIES AND THE COST OF LIQUIDITY.
- Creator
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Shao, Haimei, Yong, Jiongmin, University of Central Florida
- Abstract / Description
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The world bond market is nearly twice as large as the equity market. The goal of this dissertation is to study the dynamics of bond price. Among the liquidity risk, interest rate risk and default risk, this dissertation will focus on the liquidity risk and trading strategy. Under the mathematical frame of stochastic control, we model price setting in U.S. bond markets where dealers have multiple instruments to smooth inventory imbalances. The difficulty in obtaining the optimal trading...
Show moreThe world bond market is nearly twice as large as the equity market. The goal of this dissertation is to study the dynamics of bond price. Among the liquidity risk, interest rate risk and default risk, this dissertation will focus on the liquidity risk and trading strategy. Under the mathematical frame of stochastic control, we model price setting in U.S. bond markets where dealers have multiple instruments to smooth inventory imbalances. The difficulty in obtaining the optimal trading strategy is that the optimal strategy and value function depend on each other, and the corresponding HJB equation is nonlinear. To solve this problem, we derived an approximate optimal explicit trading strategy. The result shows that this trading strategy is better than the benchmark central symmetric trading strategy.
Show less - Date Issued
- 2011
- Identifier
- CFE0003633, ucf:48858
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0003633
- Title
- Leveraging Help Requests in POMDP Intelligent Tutors.
- Creator
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Folsom-Kovarik, Jeremiah, Sukthankar, Gita, Schatz, Sarah, Gonzalez, Avelino, Shumaker, Randall, Schatz, Sarah, University of Central Florida
- Abstract / Description
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Intelligent tutoring systems (ITSs) are computer programs that model individual learners and adapt instruction to help each learner differently. One way ITSs differ from human tutors is that few ITSs give learners a way to ask questions. When learners can ask for help, their questions have the potential to improve learning directly and also act as a new source of model data to help the ITS personalize instruction. Inquiry modeling gives ITSs the ability to answer learner questions and refine...
Show moreIntelligent tutoring systems (ITSs) are computer programs that model individual learners and adapt instruction to help each learner differently. One way ITSs differ from human tutors is that few ITSs give learners a way to ask questions. When learners can ask for help, their questions have the potential to improve learning directly and also act as a new source of model data to help the ITS personalize instruction. Inquiry modeling gives ITSs the ability to answer learner questions and refine their learner models with an inexpensive new input channel.In order to support inquiry modeling, an advanced planning formalism is applied to ITS learner modeling. Partially observable Markov decision processes (POMDPs) differ from more widely used ITS architectures because they can plan complex action sequences in uncertain situations with machine learning. Tractability issues have previously precluded POMDP use in ITS models. This dissertation introduces two improvements, priority queues and observation chains, to make POMDPs scale well and encompass the large problem sizes that real-world ITSs must confront. A new ITS was created to support trainees practicing a military task in a virtual environment. The development of the Inquiry Modeling POMDP Adaptive Trainer (IMP) began with multiple formative studies on human and simulated learners that explored inquiry modeling and POMDPs in intelligent tutoring. The studies suggest the new POMDP representations will be effective in ITS domains having certain common characteristics.Finally, a summative study evaluated IMP's ability to train volunteers in specific practice scenarios. IMP users achieved post-training scores averaging up to 4.5 times higher than users who practiced without support and up to twice as high as trainees who used an ablated version of IMP with no inquiry modeling. IMP's implementation and evaluation helped explore questions about how inquiry modeling and POMDP ITSs work, while empirically demonstrating their efficacy.
Show less - Date Issued
- 2012
- Identifier
- CFE0004506, ucf:49262
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0004506
- Title
- Evaluation of an On-Line Device to Monitor Scale Formation in a Brackish Water Reverse Osmosis Membrane Process.
- Creator
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Roque, Jennifer, Duranceau, Steven, Randall, Andrew, Zhang, Husen, University of Central Florida
- Abstract / Description
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A modified two-element membrane pressure vessel assembly has been used to monitor process operational changes in a full-scale reverse osmosis (RO) water treatment plant (WTP). This study evaluated the effectiveness of the assembly as an on-line monitoring device intended to detect scale formation conditions when connected to an operating RO process train. This study was implemented to support the requirements of a larger University of Central Florida (UCF) research project ongoing at the city...
Show moreA modified two-element membrane pressure vessel assembly has been used to monitor process operational changes in a full-scale reverse osmosis (RO) water treatment plant (WTP). This study evaluated the effectiveness of the assembly as an on-line monitoring device intended to detect scale formation conditions when connected to an operating RO process train. This study was implemented to support the requirements of a larger University of Central Florida (UCF) research project ongoing at the city of Sarasota's Public Works and Utilities (City) water treatment facilities located in Sarasota, Florida. During the time-frame of this study, the City was in the process of eliminating their sulfuric acid feed from the pretreatment system of their existing 4.5 million gallon per day (MGD) RO membrane process. The City was motivated to eliminate its dependence on sulfuric acid to reduce operating costs as well as reduce operation health and safety risks associated with the use of the acid as a pretreatment chemical. Because the City was concerned with secondary process impacts associated with acid elimination, additional measures were desired in order to protect the full-scale process.This thesis reports on the design, fabrication and installation of a third-stage two membrane element pressure vessel (")canary(") sentinel monitoring device (Canary), its effectiveness as an on-line scaling monitor during full-scale acid elimination, and presents the results of the study. The Canary sentinel device was controlled using the normalized specific flux of the two membrane elements fed by a portion of the second stage concentrate of one of the City's full-scale RO process skids. Although the Canary demonstrated the ability to detect changes in an RO process operation, scaling did not occur under the conditions evaluated in this study. An autopsy of one of the Canary elements revealed that no scaling had occurred during the acid elimination process. Therefore, the Canary was found to be useful in its function as a sentinel, even though no scaling was detected by the device after acid elimination at the City's full-scale plant had been accomplished.
Show less - Date Issued
- 2012
- Identifier
- CFE0004433, ucf:49353
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0004433
- Title
- Biogeochemical Cycling and Nutrient Control Strategies for Groundwater at Stormwater Infiltration Basins.
- Creator
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O'Reilly, Andrew, Chang, Ni-bin, Wanielista, Martin, Chopra, Manoj, Wang, Dingbao, Katz, Brian, University of Central Florida
- Abstract / Description
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Elevated concentrations of nutrients, particularly nitrate, in groundwater and springs in Florida are a growing resource management concern. Stormwater infiltration basins, which are a common stormwater management practice in the well-drained karst terrain areas of Florida, are a potentially important source of nutrients to the groundwater system because stormwater exits the basin by only evaporation or infiltration. To better understand the biogeochemical processes integrating stormwater...
Show moreElevated concentrations of nutrients, particularly nitrate, in groundwater and springs in Florida are a growing resource management concern. Stormwater infiltration basins, which are a common stormwater management practice in the well-drained karst terrain areas of Florida, are a potentially important source of nutrients to the groundwater system because stormwater exits the basin by only evaporation or infiltration. To better understand the biogeochemical processes integrating stormwater infiltration impacts on groundwater resources in a field-scale setting, a combination of hydrologic, soil chemistry, water chemistry, dissolved and soil gas, isotope, and microbiological data was collected from 2007 through 2010 at two stormwater infiltration basins receiving runoff from predominantly residential watersheds in north-central Florida. Substantially different biogeochemical processes affecting nitrogen fate and transport were observed beneath the two stormwater infiltration basins. Differences are related to soil textural properties that deeply link hydroclimatic conditions with soil moisture variations in a humid, subtropical climate. During 2008, shallow groundwater beneath the basin with predominantly clayey soils (median 41% silt+clay content) exhibited decreases in dissolved oxygen from 3.8 to 0.1 mg/L and decreases in nitrate-nitrogen from 2.7 mg/L to less than 0.016 mg/L, followed by manganese and iron reduction, sulfate reduction, and methanogenesis. In contrast, beneath the basin with predominantly sandy soils (median 2% silt+clay content), aerobic conditions persisted from 2007 through 2009 (dissolved oxygen of 5.0(-)7.8 mg/L), resulting in nitrate-nitrogen of 1.3(-)3.3 mg/L in shallow groundwater. Soil extractable nitrate-nitrogen was significantly lower and the copper-containing nitrite reductase gene density was significantly higher beneath the clayey basin. Differences in moisture retention capacity between fine- and coarse-textured soils resulted in median volumetric gas-phase contents of 0.04 beneath the clayey basin and 0.19 beneath the sandy basin, inhibiting surface/subsurface oxygen exchange beneath the clayey basin. Subsurface biogeochemical processes at the clayey stormwater infiltration basin were further analyzed to better understand the effects of the highly variable hydrologic conditions common in humid, subtropical climates. Cyclic variations in biogeochemical processes generally coincided with wet and dry hydroclimatic conditions. Oxidizing conditions in the subsurface persisted for about one month or less at the beginning of wet periods with dissolved oxygen and nitrate showing similar temporal patterns. Reducing conditions in the subsurface evolved during prolonged flooding of the basin. At about the same time oxygen and nitrate reduction concluded, manganese, iron, and sulfate reduction began, with the onset of methanogenesis one month later. Reducing conditions persisted up to six months, continuing into subsequent dry periods until the next major oxidizing infiltration event. Evidence of denitrification in shallow groundwater at the site is supported by median nitrate-nitrogen less than 0.016 mg/L, excess nitrogen gas up to 3 mg/L progressively enriched in delta-15N during prolonged basin flooding, and isotopically heavy delta-15N and delta-18O of nitrate (up to 25 and 15 per mil, respectively). Isotopic enrichment of newly infiltrated stormwater suggests denitrification was partially completed within two days. Soil and water chemistry data suggest a biogeochemically active zone exists in the upper 1.4 m of soil, where organic carbon was the likely electron donor supplied by organic matter in soil solids or dissolved in infiltrating stormwater. The cyclic nature of reducing conditions effectively controlled the nitrogen cycle, switching nitrogen fate beneath the basin from nitrate leaching to reduction in the shallow saturated zone. Soil beneath the sandy stormwater infiltration basin was amended using biosorption activated media (BAM) to study the effectiveness of this technology in reducing inputs of nitrogen and phosphorus to groundwater. The functionalized soil amendment BAM consists of a 1.0:1.9:4.1 mixture (by volume) of tire crumb (to increase sorption capacity), silt and clay (to increase soil moisture retention), and sand (to promote sufficient infiltration), which was applied to develop an innovative best management practice (BMP) utilizing nutrient reduction and flood control sub-basins. Construction and materials costs, excluding profit and permit fees, for the innovative BMP were about $US 65 per square meter of basin bottom. Comparison of nitrate/chloride ratios for the shallow groundwater indicate that prior to using BAM, nitrate concentrations were substantially influenced by nitrification or variations in nitrate input. In contrast, for the new basin utilizing BAM, nitrate/chloride ratios indicate minor nitrification and nitrate losses with the exception of one summer sample that indicated a 45% loss. Biogeochemical indicators (denitrifier activity derived from real-time polymerase chain reaction and variations in major ions, nutrients, dissolved and soil gases, and stable isotopes) suggest nitrate losses are primarily attributable to denitrification, whereas dissimilatory nitrate reduction to ammonium and plant uptake are minor processes. Denitrification was likely occurring intermittently in anoxic microsites in the unsaturated zone, which was enhanced by increased soil moisture within the BAM layer and resultant reductions in surface/subsurface oxygen exchange that produced conditions conducive to increased denitrifier activity. Concentrations of total dissolved phosphorus and orthophosphate were reduced by more than 70% in unsaturated zone soil water, with the largest decreases in the BAM layer where sorption was the most likely mechanism for removal. Post-BAM orthophosphate/chloride ratios for shallow groundwater indicate predominantly minor increases and decreases in orthophosphate with the exception of one summer sample that indicated a 50% loss. Differences in nutrient variations between the unsaturated zone and shallow groundwater may be the result of the intensity and duration of nutrient removal processes and mixing ratios with water that had undergone little biogeochemical transformation. In order to quantify potential processes leading to observed nitrogen losses beneath the innovative BMP, an integrated infiltration basin(-)nitrogen reduction (IBNR) system dynamics model was developed. Based on two simulation periods, the IBNR model indicated denitrification accounted for a loss of about one-third of the total dissolved nitrogen mass inflow and was occurring predominantly in the BAM layer. The IBNR model results in combination with the field-based biogeochemical assessment demonstrated that the innovative BMP using the functionalized soil amendment BAM is a promising passive, economical, stormwater nutrient-treatment technology. Further field- and laboratory-scale research on the long-term sustainability of nutrient losses and further elucidation of causative physicochemical and biogeochemical mechanisms would contribute to improved BAM performance and green infrastructure development in the future.
Show less - Date Issued
- 2012
- Identifier
- CFE0004419, ucf:49391
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0004419
