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(1 - 12 of 12)
- Title
- PERFORMANCE BASED DECISION SYSTEM IN DETERMINING POST CLOSURE CARE (PCC) DURATION IN FLORIDA LANDFILLS.
- Creator
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kulkarni, Asawari, Reinhart, Debra, University of Central Florida
- Abstract / Description
-
This study is an evaluation of Post Closure Care (PCC) duration of landfills using performance based methodology. The post closure care phase begins once the landfill is closed. As required by the Resource Conservation Recovery Act (RCRA) Subtitle D, PCC duration for municipal solid waste landfills is 30 years. During the PCC period, the landfill operator/owner is required to conduct monitoring for leachate, landfill gas, and ground-water and maintain the integrity of the cap so that the...
Show moreThis study is an evaluation of Post Closure Care (PCC) duration of landfills using performance based methodology. The post closure care phase begins once the landfill is closed. As required by the Resource Conservation Recovery Act (RCRA) Subtitle D, PCC duration for municipal solid waste landfills is 30 years. During the PCC period, the landfill operator/owner is required to conduct monitoring for leachate, landfill gas, and ground-water and maintain the integrity of the cap so that the landfill does not impose a threat to surrounding human health and environment (HH&E). The duration of PCC can be reduced by the director of an approved State if an owner/operator of a landfill demonstrates that the landfill exhibits no threat to the surrounding HH&E or can be increased if the director of the approved State determines that an increased PCC period is required for the protection of HH&E. RCRA provides flexibility in optimizing PCC duration of landfills, although it does not identify the criteria/methodology which can be used in demonstrating the status of a landfill from the point of PCC. Researchers worldwide recognize that the threat imposed by a landfill after closure depends on the extent of degradation occurring inside the landfill. The increased functional stability of landfills reduces its risk to the surrounding HH&E. However, there is a wide range of opinions in defining functional stability of a landfill. The present thesis applies performance based methodology, developed by Environmental Research and Education Foundation (EREF), to making a decision on the PCC of landfills. Performance based methodology is a modular approach encompassing all four PCC components of landfills (Leachate, gas, groundwater and cap maintenance). This methodology was applied to Alachua County Southwest Landfill (ACSWLF) in Alachua County, Florida. Each module was analyzed individually and recommendations on the PCC monitoring at the landfill site were provided.
Show less - Date Issued
- 2008
- Identifier
- CFE0002471, ucf:47700
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0002471
- Title
- THE USE OF FILTERS IN TOPOLOGY.
- Creator
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Dasser, Abdellatif, Richardson, Gary, University of Central Florida
- Abstract / Description
-
Sequences are sufficient to describe topological properties in metric spaces or, more generally, topological spaces having a countable base for the topology. However, filters or nets are needed in more abstract spaces. Nets are more natural extension of sequences but are generally less friendly to work with since quite often two nets have distinct directed sets for domains. Operations involving filters are set theoretic and generally certain to filters on the same set. The concept of a filter...
Show moreSequences are sufficient to describe topological properties in metric spaces or, more generally, topological spaces having a countable base for the topology. However, filters or nets are needed in more abstract spaces. Nets are more natural extension of sequences but are generally less friendly to work with since quite often two nets have distinct directed sets for domains. Operations involving filters are set theoretic and generally certain to filters on the same set. The concept of a filter was introduced by H. Cartan in 1937 and an excellent treatment of the subject can be found in N. Bourbaki (1940).
Show less - Date Issued
- 2004
- Identifier
- CFE0000202, ucf:46271
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0000202
- Title
- PERCEPTUAL GROUPING BY CLOSURE IN VISUAL WORKING MEMORY.
- Creator
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Neira, Sofia, Neider, Mark, University of Central Florida
- Abstract / Description
-
Research on visual working memory (VWM) suggests a capacity limit of three to four objects (Luck & Vogel, 1997), but recent studies on the fidelity of VWM capacity for objects indicates that informational bandwidth, which can vary with factors like complexity and amenability to perceptual grouping, can interact with this capacity (Brady, Konkle & Alvarez, 2011). For example, individual features can be grouped into objects for an added benefit in VWM capacity (Xu, 2002). Along these lines, the...
Show moreResearch on visual working memory (VWM) suggests a capacity limit of three to four objects (Luck & Vogel, 1997), but recent studies on the fidelity of VWM capacity for objects indicates that informational bandwidth, which can vary with factors like complexity and amenability to perceptual grouping, can interact with this capacity (Brady, Konkle & Alvarez, 2011). For example, individual features can be grouped into objects for an added benefit in VWM capacity (Xu, 2002). Along these lines, the Gestalt principles of proximity and connectedness have been shown to benefit VWM, although they do not influence capacity equally (Xu 2006; Woodman, Vecera & Luck, 2003). Closure, which has not been investigated for its influence in VWM capacity, is similar to connectedness and proximity as it promotes the perception of a coherent object without physical connections. In the current experiment, we evaluated whether closure produces similar or greater VWM capacity advantages compared to proximity by having participants engage in a change detection task. Four L-shaped features were grouped in tilted clusters to either form an object (closure condition) or not (no-object condition), with a set size of two (8 L features), four (16 L features), or six clusters (24 L features). Following a brief mask (1000 ms), the orientation of one cluster was changed (tilted 25 or -25 degrees) on half the trials. Our results indicate that there was no difference in accuracy or reaction time for the perceptual grouping conditions of closure/no-object, although we did find a main effect for set size and change conditions. Overall, it seems that grouping by closure provides no further advantages to VWM capacity than proximity; however, more experiments need to be conducted to solidify the findings of the current experiment.
Show less - Date Issued
- 2016
- Identifier
- CFH2000038, ucf:45604
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFH2000038
- Title
- WORK ZONE EFFECTS ON PERFORMANCE OF A TOLL PLAZA.
- Creator
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liu, jingyu, Radwan, Essam, University of Central Florida
- Abstract / Description
-
No-lane closure workzone is typical during the construction of open road tolling lanes of a toll plaza. The influence of no-lane closure on toll plazas' performance is unknown because very few studies have been conducted to address this topic. The open road tolling (ORT) has become the new trend of operating an efficient toll plaza. So, the upgrading of a toll plaza from gated E-pass to open road E-pass has become common. The better the toll plaza authority knows about the influence of...
Show moreNo-lane closure workzone is typical during the construction of open road tolling lanes of a toll plaza. The influence of no-lane closure on toll plazas' performance is unknown because very few studies have been conducted to address this topic. The open road tolling (ORT) has become the new trend of operating an efficient toll plaza. So, the upgrading of a toll plaza from gated E-pass to open road E-pass has become common. The better the toll plaza authority knows about the influence of this construction and congestion effects, the better it can serve the costumers. This project mainly deals with the effects of no-lane closure workzone on the toll plaza performance, and with the collected data, a model was developed predicting 15 minutes throughput and queue length. To better study the workzone impact on toll plaza performance, three sites with different characteristics were selected. They are Lake Jesup Mainline Plaza along the Seminole Expressway (SR-417), the Beachline West Expressway Toll Plaza along the SR-528 and Conway toll plaza along the Holland East-West Expressway (SR-408) in Orlando area of Central Florida. Data preparation includes demand, throughput, processing rates, and queue lengths of different toll categories. Data was collected during peak period for before and during the no-lane closure construction (phase 1) at SR-528 and Lake Jesup toll plaza at SR-417, and middle lane construction (phase 2) and after opening ORT lanes (phase 3) at Conway toll plaza at SR-408.Comparisons were conducted between non-construction stage and construction stage for non-lane closure workzone effects study using data from 417 and 528, and comparisons between middle-lane-construction and complete of construction stage for ORT impact study using data from 408. Analysis results showed that when the toll plaza is operating at or close to its capacity, the no-lane closure workzone can have a negative impact on its performance. But when the toll plaza's demand is lower than the capacity, the no-lane closure workzone has no impact at the toll plaza's performance. And the ORT lanes have a positive influence on the capacity and throughput of the toll plaza. After the impact of no-lane closure workzone on toll plaza has been analyzed, all the data from three toll plazas are put together and a model is built using the variables of Demand/Capacity ratio, percentage of each category of vehicles, E-pass, Automatic or Manual, number of Manual lanes, workzone or no-workzone. Throughput and Queue length can be predicted by this model.
Show less - Date Issued
- 2009
- Identifier
- CFE0002951, ucf:47940
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0002951
- Title
- Business Closure in the North American Theme Park Industry: An Analysis of Causes.
- Creator
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Kaak, Kelly, Milman, Ady, Breiter Terry, Deborah, Mendez, Jesse, Schuckert, Markus, University of Central Florida
- Abstract / Description
-
Prior to this study, no analysis had focused on the 31% failure rate recorded among theme parks opened in North American between the years 1955 and 2009. This study's purpose was to identify the causes of closures among the 23 failed theme parks and inform the industry of what can be learned from these business failures. Business failure analysis typically stresses the impact of financial ratios and the accuracy of certain negative numbers to predict impending failure, but such studies avoid...
Show morePrior to this study, no analysis had focused on the 31% failure rate recorded among theme parks opened in North American between the years 1955 and 2009. This study's purpose was to identify the causes of closures among the 23 failed theme parks and inform the industry of what can be learned from these business failures. Business failure analysis typically stresses the impact of financial ratios and the accuracy of certain negative numbers to predict impending failure, but such studies avoid examining the underlying causes that lead to poor financial performance in the first place. To focus on this question, this study adopted an events approach to discover the actual event causes that preceded failure and business closure. This study tabulated the frequency of event occurrences among two samples: failed/closed theme parks and a comparable sample of surviving theme parks. Event occurrences were more common among the failed/closed sample than among the surviving theme parks sample. A detailed analysis revealed that six of the 21 events measured were more common among the failed/closed theme park sample: declaring bankruptcy; excessive debt or general unprofitability; low customer satisfaction, defined as not offering enough to do in the park and/or inadequate capacity; development pressures; limited space for expansion; and a location in a regional geographic market. Theme parks failed more frequently due to involuntary event causes than due to voluntary closures. And, in contrast to previous studies, the occurrences of internal environmental events associated with business failure were not significantly different from the occurrences of external environmental events associated with failure. These findings identified events that have preceded failure or closure in theme parks and can provide insights to operators and industry decision makers on how best to prevent or better manage such business closures in the future.
Show less - Date Issued
- 2018
- Identifier
- CFE0007026, ucf:52030
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0007026
- Title
- Large Eddy Simulations with a Tabulated Conditional Moment Closure Moment Closure Model for Turbulent Premixed Combustion with Heat Loss.
- Creator
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Velez, Carlos, Vasu Sumathi, Subith, Martin, Scott, Kassab, Alain, Das, Tuhin, University of Central Florida
- Abstract / Description
-
The Tabulated Premixed Conditional Moment Closure (T-PCMC) method has been shown to provide the capability to predict turbulent, premixed methane flames with detailed chemistry and reasonable run times in a RANS/URANS adiabatic environment. Here the premixed T-PCMC method is extended in a Large Eddy Simulation (LES) framework for non-adiabatic premixed flames, allowing heat loss to occur in the mixture before, during and after combustion. It is proposed that the LES framework is a more...
Show moreThe Tabulated Premixed Conditional Moment Closure (T-PCMC) method has been shown to provide the capability to predict turbulent, premixed methane flames with detailed chemistry and reasonable run times in a RANS/URANS adiabatic environment. Here the premixed T-PCMC method is extended in a Large Eddy Simulation (LES) framework for non-adiabatic premixed flames, allowing heat loss to occur in the mixture before, during and after combustion. It is proposed that the LES framework is a more suitable representation for both chemical and turbulent scales in premixed combustion. By resolving the high energy turbulent scales and modeling the small scale turbulence, it is expected that the resolution of the turbulence and transient effects are better captured in a LES framework leading to better predictions of the mixing rate and consequently the reaction rate, which is the main focus and source of error in combustion modeling. The LES T-PCMC model is implemented using the open source CFD software OpenFOAM for its open access to C++ source code and large library of turbulence and thermo-physical models. The proposed model validated with PIV and Raman measurements of a turbulent, enclosed reacting flame of a single jet and backward facing step geometry. The DLR data sets provide both unity (E.g.Methane) and non-unity (E.g. Hydrogen) Lewis number fuels, allowing for the proposed numerical model to be validated against both unity and non-unity Lewis # flames. Velocity, temperature and major/minor species are compared to the experimental data. Once validated, this model is intended to be useful for designing lean premixed combustors for gas turbines which operate primarily in the corrugated premixed combustion regime, where chemical and turbulent time scales are of the same order requiring adequate models for their interaction.LES results match the experimental data better than the Reynolds Averaged Navier-Stokes (RANS/URANS) solution and is able to better resolve the transient features of the flame with an increase in run time of only 50 %, when compared to URANS.
Show less - Date Issued
- 2015
- Identifier
- CFE0006234, ucf:51058
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0006234
- Title
- EFFECT OF LASER IRIDOPLASTY ON PULSATILE OCULAR BLOOD FLOW IN PRIMARY ANGLE-CLOSURE GLAUCOMA AND PRIMARY ANGLE-CLOSURE SUSPECTS.
- Creator
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Hill, Mathieu, Saleh, Suha, University of Central Florida
- Abstract / Description
-
Angle-closure glaucoma is a leading cause of blindness in the United States and around the world. New research has indicated that intraocular pressure is not the only risk factor associated with glaucomatous optic neuropathy. In recent years, a vascular deregulation in ocular blood flow has been considered a possible risk factor in glaucoma. A laser peripheral iridoplasty is a standard treatment option in non-pupillary block angle-closure glaucoma. The present study employed a secondary...
Show moreAngle-closure glaucoma is a leading cause of blindness in the United States and around the world. New research has indicated that intraocular pressure is not the only risk factor associated with glaucomatous optic neuropathy. In recent years, a vascular deregulation in ocular blood flow has been considered a possible risk factor in glaucoma. A laser peripheral iridoplasty is a standard treatment option in non-pupillary block angle-closure glaucoma. The present study employed a secondary retrospective design and utilized patient's data from an ophthalmologist's practice. The purpose of this study was to examine the effect of laser peripheral iridoplasty on pulsatile ocular blood flow in primary angle-closure glaucoma and primary angle-closure suspects. A sample of 30 eyes from 17 patients was analyzed for this study. A significant increase in pulsatile ocular blood flow was found among primary angle-closure suspects. Additional data analysis was performed through SPSS software to examine the effect on these variables by age, sex and medical history as a total sample and in each group. Primary angle-closure suspects who were 51-60 years old showed a significant increase in intraocular pressure after laser treatment, however, primary angle-closure glaucoma patients who were 71-80 years old showed a significant decrease in intraocular pressure. Furthermore, a significant increase in pulsatile ocular blood flow was found in female subjects among primary angle-closure suspects, supporting the need for gender medicine research. Lastly, the pulsatile ocular blood flow increased significantly among primary angle-closure suspects who were also suffering from cardiovascular disease. Among primary angle-closure glaucoma patients who were suffering from both cardiovascular disease and diabetes mellitus, a significant decrease in intraocular pressure was observed.
Show less - Date Issued
- 2015
- Identifier
- CFH0004874, ucf:45427
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFH0004874
- Title
- AUTONOMOUS ROBOTIC GRASPING IN UNSTRUCTURED ENVIRONMENTS.
- Creator
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Jabalameli, Amirhossein, Behal, Aman, Haralambous, Michael, Pourmohammadi Fallah, Yaser, Boloni, Ladislau, Xu, Yunjun, University of Central Florida
- Abstract / Description
-
A crucial problem in robotics is interacting with known or novel objects in unstructured environments. While the convergence of a multitude of research advances is required to address this problem, our goal is to describe a framework that employs the robot's visual perception to identify and execute an appropriate grasp to pick and place novel objects. Analytical approaches explore for solutions through kinematic and dynamic formulations. On the other hand, data-driven methods retrieve grasps...
Show moreA crucial problem in robotics is interacting with known or novel objects in unstructured environments. While the convergence of a multitude of research advances is required to address this problem, our goal is to describe a framework that employs the robot's visual perception to identify and execute an appropriate grasp to pick and place novel objects. Analytical approaches explore for solutions through kinematic and dynamic formulations. On the other hand, data-driven methods retrieve grasps according to their prior knowledge of either the target object, human experience, or through information obtained from acquired data. In this dissertation, we propose a framework based on the supporting principle that potential contacting regions for a stable grasp can be foundby searching for (i) sharp discontinuities and (ii) regions of locally maximal principal curvature in the depth map. In addition to suggestions from empirical evidence, we discuss this principle by applying the concept of force-closure and wrench convexes. The key point is that no prior knowledge of objects is utilized in the grasp planning process; however, the obtained results show thatthe approach is capable to deal successfully with objects of different shapes and sizes. We believe that the proposed work is novel because the description of the visible portion of objects by theaforementioned edges appearing in the depth map facilitates the process of grasp set-point extraction in the same way as image processing methods with the focus on small-size 2D image areas rather than clustering and analyzing huge sets of 3D point-cloud coordinates. In fact, this approach dismisses reconstruction of objects. These features result in low computational costs and make it possible to run the proposed algorithm in real-time. Finally, the performance of the approach is successfully validated by applying it to the scenes with both single and multiple objects, in both simulation and real-world experiment setups.
Show less - Date Issued
- 2019
- Identifier
- CFE0007892, ucf:52757
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0007892
- Title
- Visuo-spatial abilities in remote perception: A meta-analysis of empirical work.
- Creator
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Fincannon, Thomas, Jentsch, Florian, Sims, Valerie, Bowers, Clint, Chen, Jessie, University of Central Florida
- Abstract / Description
-
Meta-analysis was used to investigate the relationship between visuo-spatial ability and performance in remote environments. In order to be included, each study needed to examine the relationship between the use of an ego-centric perspective and various dimensions of performance (i.e., identification, localization, navigation, and mission completion time). The moderator analysis investigated relationships involving: (a) visuo-spatial construct with an emphasis on Carroll's (1993)...
Show moreMeta-analysis was used to investigate the relationship between visuo-spatial ability and performance in remote environments. In order to be included, each study needed to examine the relationship between the use of an ego-centric perspective and various dimensions of performance (i.e., identification, localization, navigation, and mission completion time). The moderator analysis investigated relationships involving: (a) visuo-spatial construct with an emphasis on Carroll's (1993) visualization (VZ) factor; (b) performance outcome (i.e., identification, localization, navigation, and mission completion time); (c) autonomy to support mission performance; (d) task type (i.e., navigation vs. reconnaissance); and (e) experimental testbed (i.e., physical vs. virtual environments). The process of searching and screening for published and unpublished analyses identified 81 works of interest that were found to represent 50 unique datasets. 518 effects were extracted from these datasets for analyses.Analyses of aggregated effects (Hunter (&) Schmidt, 2004) found that visuo-spatial abilities were significantly associated with each construct, such that effect sizes ranged from weak (r = .235) to moderately strong (r = .371). For meta-regression (Borenstein, Hedges, Figgins, (&) Rothstein, 2009; Kalaian (&) Raudenbush, 1996; Tabachnick (&) Fidell, 2007), moderation by visuo-spatial construct (i.e., focusing on visualization) was consistently supported for all outcomes. For at least one of the outcomes, support was found for moderation by test, the reliability coefficient of a test, autonomy (i.e. to support identification, localization, and navigation), testbed (i.e., physical vs. virtual environment), intended domain of application, and gender. These findings illustrate that majority of what researchers refer to as (")spatial ability(") actually uses measures that load onto Carroll's (1993) visualization (VZ) factor. The associations between this predictor and all performance outcomes were significant, but the significant variation across moderators highlight important issues for the design of unmanned systems and the external validity of findings across domains. For example, higher levels of autonomy for supporting navigation decreased the association between visualization (VZ) and performance. In contrast, higher levels of autonomy for supporting identification and localization increased the association between visualization (VZ) and performance. Furthermore, moderation by testbed, intended domain of application, and gender challenged the degree to which findings can be expected to generalize across domains and sets of participants.
Show less - Date Issued
- 2013
- Identifier
- CFE0004680, ucf:49858
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0004680
- Title
- Treatment of Leachate Organic Matter through Sunlight Driven Processes.
- Creator
-
Lozinski, Duncan, Reinhart, Debra, Lee, Woo Hyoung, Bolyard, Stephanie, University of Central Florida
- Abstract / Description
-
The ability to manage leachate during post-closure care (PCC) of a landfill may be increasingly difficult as leachate organic matter (LOM) becomes recalcitrant when a landfill ages, requiring advanced and costly treatment technologies. This research investigated the ability to treat LOM through sunlight driven processes, with a focus on photolysis, to provide insight to landfill owners and operators on the potential of wetlands treatment as a means for reducing long-term risks and costs...
Show moreThe ability to manage leachate during post-closure care (PCC) of a landfill may be increasingly difficult as leachate organic matter (LOM) becomes recalcitrant when a landfill ages, requiring advanced and costly treatment technologies. This research investigated the ability to treat LOM through sunlight driven processes, with a focus on photolysis, to provide insight to landfill owners and operators on the potential of wetlands treatment as a means for reducing long-term risks and costs associated with leachate treatment during PCC. The study was completed in eight batch tests, where leachate was exposed to natural sunlight in central Florida for a period of 90 days. It was hypothesized that through photolytic reactions, in particular photolysis, high molecular weight recalcitrant LOM would be degraded to labile, low molecular weight material. To identify the treatment mechanisms, transformation processes were measured using ultraviolet-visible (UV-Vis) spectroscopy, fluorescence excitation-emission matrix spectroscopy (EEMs), size-exclusion chromatography (SEC), and chemical oxygen demand (COD) from the beginning to the end of the test period. Additionally, the ability for nitrogen species to become bioavailable when exposed to sunlight was evaluated for two of the leachate samples using solid-phase extraction (SPE) to fractionate recalcitrant dissolved organic nitrogen (rDON) and bioavailable dissolved organic nitrogen (bDON). Results suggest that treatment of LOM through sunlight driven processes is possible. Treatment is dependent upon the dilution of leachate and characteristics of the LOM. Dilution must be high enough to allow sunlight to penetrate the depth of the liquid. UV-Vis, EEMs, and SEC show that high molecular weight recalcitrant material is undergoing transformation into lower molecular weight material as a result of photolytic and likely biological reactions promoted by sunlight. The ability for nitrogen to become bioavailable when exposed to sunlight was shown to be dependent upon nitrogen concentrations in the sample.
Show less - Date Issued
- 2018
- Identifier
- CFE0007044, ucf:51987
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0007044
- Title
- Application of Landfill Treatment Approaches for the Stabilization of Municipal Solid Waste.
- Creator
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Bolyard, Stephanie, Reinhart, Debra, Santra, Swadeshmukul, Randall, Andrew, University of Central Florida
- Abstract / Description
-
This research focused on the fundamental requirements of stabilizing a mature landfill using three treatment approaches as well as the implications of discharging leachate organic matter (LOM) to wastewater treatment plants (WWTPs). Three treatment approaches aimed at removing releasable carbon and nitrogen from mature landfills including flushing with clean water, leachate recirculation with ex-situ chemical oxidation, and leachate recirculation with ex-situ chemical oxidation and in-situ...
Show moreThis research focused on the fundamental requirements of stabilizing a mature landfill using three treatment approaches as well as the implications of discharging leachate organic matter (LOM) to wastewater treatment plants (WWTPs). Three treatment approaches aimed at removing releasable carbon and nitrogen from mature landfills including flushing with clean water, leachate recirculation with ex-situ chemical oxidation, and leachate recirculation with ex-situ chemical oxidation and in-situ aeration were evaluated. After extensive treatment of the waste in the flushing bioreactor (FB) scenarios, the overall biodegradable fraction was reduced relative to mature waste. Leachate quality improved for all FBs but through different mechanisms. Flushing was the most effective approach at removing biodegradable components and improving leachate quality. A mass balance on carbon and nitrogen revealed that a significant fraction still remained in the waste. Solid waste and leachate samples from the anaerobic bioreactors and FBs were characterized using Fourier Transform Infrared (FTIR) to provide a better understanding of changes in waste characteristics when waste transitions from mature to stabilized. Organic functional groups associated with aliphatic methylene were present in leachate and solid waste samples during the early stages of anaerobic degradation and disappeared once these wastes underwent treatment. Once the waste was stabilized, the FTIR spectra of leachate and solid waste were dominated by inorganic functional groups (carboxylic acid/carbonate group, carbonate, quartz, and clay minerals). Leachate is commonly co-treated with domestic wastewater due to the cost and complexity of on-site treatment. The organic constituents in leachate can be problematic for WWTPs as their recalcitrant components pass through conventional treatment processes, impacting effluent quality. Twelve leachates where characterized for total nitrogen (TN) and dissolved organic nitrogen (DON). The average concentration of TN and DON in leachate was 1,160 and 40.7 mg/L, respectively. Leachates were fractionated based on hydrophobic (recalcitrant; rDON) and hydrophilic (bioavailable; bDON) properties. The average concentrations of bDON and rDON were 16.5 and 18.4 mg/L, respectively. Multiple leachate and wastewater co-treatment simulations were carried out to assess the treatment of leachate nitrogen at historic nitrogen removal levels of four WWTPs and the effects on wastewater effluent quality for four WWTPs. The effluent quality exceeded typical TN limits of 3 to 10 mg/L at leachate volumetric contributions of 10%. The maximum calculated pass through concentrations of rDON and DON at 10% volumetric contribution for the twelve leachates was 4.77 and 9.71 mg/L, respectively. The effects of LOM on wastewater effluent quality was further evaluated in the field. Results showed that leachate detection for each field study could be determined using UV254 nm absorbance. DON and dissolved organic carbon (DOC) concentrations increased at significant levels in leachate-impacted wastewater samples. The DON decreased through the treatment train, suggesting that this parameter was effectively removed, while DOC persisted. DOC pass through coincided with an increase in color and UV254 nm absorption. In effluents, the UV254 nm transmittance was just below the minimum 65% disinfection requirement at dilutions greater than 1%. Leachate-impacted wastewater showed a higher concentration of humic-like peaks during fluorescence measurements than wastewater without leachate.
Show less - Date Issued
- 2016
- Identifier
- CFE0006076, ucf:50959
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0006076
- Title
- Lattice-Valued T-Filters and Induced Structures.
- Creator
-
Reid, Frederick, Richardson, Gary, Brennan, Joseph, Han, Deguang, Lang, Sheau-Dong, University of Central Florida
- Abstract / Description
-
A complete lattice is called a frame provided meets distribute over arbitrary joins. The implication operation in this context plays a central role. Intuitively, it measures the degree to which one element is less than or equal to another. In this setting, a category is defined by equipping each set with a T-convergence structure which is defined in terms of T-filters. This category is shown to be topological, strongly Cartesian closed, and extensional. It is well known that the category of...
Show moreA complete lattice is called a frame provided meets distribute over arbitrary joins. The implication operation in this context plays a central role. Intuitively, it measures the degree to which one element is less than or equal to another. In this setting, a category is defined by equipping each set with a T-convergence structure which is defined in terms of T-filters. This category is shown to be topological, strongly Cartesian closed, and extensional. It is well known that the category of topological spaces and continuous maps is neither Cartesian closed nor extensional.Subcategories of compact and of complete spaces are investigated. It is shown that each T-convergence space has a compactification with the extension property provided the frame is a Boolean algebra. T-Cauchy spaces are defined and sufficient conditions for the existence of a completion are given. T-uniform limit spaces are also defined and their completions are given in terms of the T-Cauchy spaces they induce. Categorical properties of these subcategories are also investigated. Further, for a fixed T-convergence space, under suitable conditions, it is shown that there exists an order preserving bijection between the set of all strict, regular, Hausdorff compactifications and the set of all totally bounded T-Cauchy spaces which induce the fixed space.
Show less - Date Issued
- 2019
- Identifier
- CFE0007520, ucf:52586
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0007520
