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Title: AN INVESTIGATION TO DETERMINE THE LEVEL OF KNOWLEDGE OF FACILITY MAINTENANCE BY PUBLIC SCHOOL-BUILDING LEVEL ADMINISTRATORS.
Creator: Paradise, Richard, Murray, Kenneth, University of Central Florida
Abstract / Description: This investigation studied the level of knowledge that principals have concerning the maintenance of their schools. A questionnaire was developed to address three research questions. These research questions were: (1) what is the extent that facilities maintenance is an important issue for school principals? (2) in what specific areas of facilities maintenance do principals lack knowledge? and (3) in what specific areas does the lack of facilities maintenance knowledge by principals exceed 30...
Show moreThis investigation studied the level of knowledge that principals have concerning the maintenance of their schools. A questionnaire was developed to address three research questions. These research questions were: (1) what is the extent that facilities maintenance is an important issue for school principals? (2) in what specific areas of facilities maintenance do principals lack knowledge? and (3) in what specific areas does the lack of facilities maintenance knowledge by principals exceed 30%? A questionnaire was developed to gather data to analyze comparative relationships to the research questions. Data indicated that principals do believe facilities maintenance is an important issue. Reponses to the questionnaire indicated most principals have a general understanding of facilities maintenance in its broadest sense. However, the data supported that most principals lack knowledge concerning the specific facilities maintenance information and issues. Recommendations were made to address the lack of knowledge principals have concerning facilities maintenance. Recommendations were also made for additional research in the area of the principal's knowledge concerning facilities maintenance.
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Date Issued: 2006
Identifier: CFE0001200, ucf:46943
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0001200

Title: Accelerated flight test data as a basis for forecasting logistical requirements of military aircraft.
Creator: White, Charles James, Doering, R. D., Engineering
Abstract / Description: University of Central Florida College of Engineering Thesis; The initial forecasting of logistical support for new types of military aircraft is a perplexing problem. The objective of this research was to investigate the feasibility of using data generated by the accelerated flight tests as a basis for forecasting the logistical field requirements. The data used in the study were obtained from the U.S. Army Aviation Board, Fort Rucker, Alabama, where performance tests are conducted on all new...
Show moreUniversity of Central Florida College of Engineering Thesis; The initial forecasting of logistical support for new types of military aircraft is a perplexing problem. The objective of this research was to investigate the feasibility of using data generated by the accelerated flight tests as a basis for forecasting the logistical field requirements. The data used in the study were obtained from the U.S. Army Aviation Board, Fort Rucker, Alabama, where performance tests are conducted on all new aircraft to determine their suitability for Army use. It was statistically shown that the use of these data could provide more realistic logistical forecasts earlier in the introductory phase of the aircraft. This concept would increase the operational availability of the aircraft and reduce the cost of maintaining the aircraft during its introductory phase.
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Date Issued: 1979
Identifier: CFR0003498, ucf:53013
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFR0003498

Title: CROSSING THE LINE IN CROSS-SEX FRIENDSHIPS: EFFECTS OF PAST SEXUAL CONTACT AND DATING STATUS ON RELATIONAL MAINTENANCE.
Creator: Emmett, Melissa, Weger, Jr., Harry, University of Central Florida
Abstract / Description: Given that male-female friendships lack institutional guidelines or scripts to guide everyday interactions, sustaining these relationships can be complicated. Although researchers have recently begun to study relational maintenance patterns in cross-sex friendships, no study has yet to investigate sex's and dating status's direct influences on friendship maintenance. This investigation seeks to add to the field's academic understanding of these personal relationships. Specifically...
Show moreGiven that male-female friendships lack institutional guidelines or scripts to guide everyday interactions, sustaining these relationships can be complicated. Although researchers have recently begun to study relational maintenance patterns in cross-sex friendships, no study has yet to investigate sex's and dating status's direct influences on friendship maintenance. This investigation seeks to add to the field's academic understanding of these personal relationships. Specifically, the researcher sought to uncover the associations between 10 friendship maintenance behaviors, past sexual contact, valence of past sexual contact, and cross-sex friends' dating statuses. Quantitative data were collected from 277 participants at a large Southeastern university using a survey methodology. Overall, results indicate that patterns of relational maintenance do differ as a function of friendship level, past sexual involvement, valence of past sexual involvement, and cross-sex friends' dating statuses. Past sexual involvement associates with higher levels of relationship talk, avoidance of negativity, and flirting. In addition, valence of past sexual activity varies across friendship level and associates with higher levels of positivity and flirting. Lastly, dating status significantly affects 3 of the 10 maintenance behaviors: routine contact and activity, flirting, and humor. Linear, quadratic, and cubic relationships were found for these variables, respectively. Implications of results, limitations, and recommendations for future research are discussed.
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Date Issued: 2008
Identifier: CFE0002070, ucf:47585
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0002070

Title: POSITIVE OUTCOMES OF DIVORCE: A MULTI-METHOD STUDY ON THE EFFECTS OF PARENTAL DIVORCE ON CHILDREN.
Creator: Mohi, Grant, Grauerholz, Elizabeth, University of Central Florida
Abstract / Description: A great deal of the existing literature on parental divorce focuses on the negative influences it has on children and young adults in regards to such areas as their relationships (romantic and familial) and their academic standing. The implications of such research are that parental divorce will always bring harm to families and, consequentially, should be avoided for the sake of the children's wellbeing. What is often missing from this research is a focus on the potential positive outcomes...
Show moreA great deal of the existing literature on parental divorce focuses on the negative influences it has on children and young adults in regards to such areas as their relationships (romantic and familial) and their academic standing. The implications of such research are that parental divorce will always bring harm to families and, consequentially, should be avoided for the sake of the children's wellbeing. What is often missing from this research is a focus on the potential positive outcomes of parental divorce. The intent of this thesis is to explore the effects of parental divorce on young adults' ability to form and maintain romantic relationships, focusing on the positive outcomes of parental divorce on young adults and seeking to answer the question of whether or not young adults can actually benefit from their parents' divorce. By surveying a sample of 233 students from divorced and intact families from a large university on their experiences with parental divorce and/or romantic relationships, in conjunction with face to face interviews, the current study provides a deeper insight into the social factors that help define divorce as positive and explores the effects of family structure, gender of child, economic situation, and pre-existing parental conflict on young adults of divorced parents. Findings suggest that these young adults do experience positive outcomes after the divorce and that these outcomes are dependent on a variety of familial and social factors that shape the divorce experience.
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Date Issued: 2014
Identifier: CFH0004550, ucf:45226
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFH0004550

Title: FOOD FOR THOUGHT: THE RELATIONSHIP BETWEEN THOUGHT SUPPRESSION AND WEIGHT CONTROL.
Creator: Peterson, Rachel, Tantleff Dunn, Stacey, University of Central Florida
Abstract / Description: The current study assessed the relationship between individuals' tendency to suppress thoughts, particularly related to food and body weight/shape, and outcomes such as weight loss maintenance and diet sabotaging experiences (e.g., binge eating). Community and university individuals (N = 347) who are or previously were overweight completed self-report measures of thought suppression, weight history, and eating behaviors. Suppression of specific thoughts about food/weight/shape was related...
Show moreThe current study assessed the relationship between individuals' tendency to suppress thoughts, particularly related to food and body weight/shape, and outcomes such as weight loss maintenance and diet sabotaging experiences (e.g., binge eating). Community and university individuals (N = 347) who are or previously were overweight completed self-report measures of thought suppression, weight history, and eating behaviors. Suppression of specific thoughts about food/weight/shape was related to weight cycling, binge eating, and food cravings. Participants who believed thoughts of food lead to eating were more likely to attempt suppression of food-related thoughts. Results have implications for improving weight loss maintenance and support further exploration of third wave interventions, such as Acceptance and Commitment Therapy and Mindfulness, in the treatment of obesity.
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Date Issued: 2008
Identifier: CFE0002231, ucf:47906
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0002231

Title: Utilization of Ambulatory Services by the Health Maintenance Organization of Florida.
Creator: Hansen, Thomas Harold, Mendenhall, Thomas S., Health
Abstract / Description: University of Central Florida College of Health Thesis; The utilization of ambulatory services by the health maintenance organization of Florida (HMO), independent practice association (IPA) model, was compared to a fee-for-service population. Each randomly selected group consisted of 250 patients being cared for by the same providers, at the same clinic, during the calendar year 1986. Demographic and clinical data was gathered from the office charts. Frequencies were evaluated by the...
Show moreUniversity of Central Florida College of Health Thesis; The utilization of ambulatory services by the health maintenance organization of Florida (HMO), independent practice association (IPA) model, was compared to a fee-for-service population. Each randomly selected group consisted of 250 patients being cared for by the same providers, at the same clinic, during the calendar year 1986. Demographic and clinical data was gathered from the office charts. Frequencies were evaluated by the Statistical Package for the Social Sciences and t-tests were run to substantiate variance at the 0.05 level of confidence. The HMO group is a younger population (t=0.017), and the males are responsible for the increased utilization of ambulatory services (t-0.001). Trends of increased utilization are noted across the age groups and the variables. The rate of hospitalization is insignificantly higher for the HMO population and covers a broader range of age groups. Consequently, this HMO IPA model increases the rate of ambulatory service utilization in a younger population without reducing the rate of hospitalization. Cost effectiveness studies and organizational management evaluations are needed.
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Date Issued: 1988
Identifier: CFR0008167, ucf:53069
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFR0008167

Title: Safety Climate and Safety Outcomes in Aircraft Maintenance: A Mediating Effect of Employee Turnover and Safety Motivation.
Creator: Alnoaimi, Muhanna, Karwowski, Waldemar, Xanthopoulos, Petros, Hancock, Peter, Mikusinski, Piotr, University of Central Florida
Abstract / Description: Aircraft maintenance is viewed as a critical safety component in general and military aviation industries, and thus it is crucial to identify the factors that may affect aircraft maintenance. Because the safety climate is considered as a leading indicator of safety performance and safety outcomes, this study utilized this safety climate approach to develop a model which can explain the relationships between employee turnover, safety motivation, self-reported unsafe acts, reporting unsafe...
Show moreAircraft maintenance is viewed as a critical safety component in general and military aviation industries, and thus it is crucial to identify the factors that may affect aircraft maintenance. Because the safety climate is considered as a leading indicator of safety performance and safety outcomes, this study utilized this safety climate approach to develop a model which can explain the relationships between employee turnover, safety motivation, self-reported unsafe acts, reporting unsafe behaviors, incidents, and injuries in the aviation maintenance environment. This study included a sample of 283 technicians in military aircraft maintenance units who participated in a cross-sectional random survey. Data collected were analyzed using Exploratory Factor Analysis (EFA) and Structural Equation Modeling (SEM) techniques. A structural model that fitted the data was developed which predicted 64% of the variance in employee turnover, 7% of the variance in safety motivation, 20% of the variance in unsafe acts, 41% of the variance in reporting unsafe behavior, and 21% of the variance in workplace injuries. The results indicate employees who report a perception of high turnover exhibit decreased safety motivation and increased unsafe acts which lead to higher levels of workplace injuries. The perception of safety climate was identified as an antecedent to safety performance and safety outcomes. Additionally, the effects of control variables such as age and education were tested. The implications for safety management in aircraft maintenance were also discussed. This study provides directions for future research on the turnover of aircraft maintenance technicians, safety performance, and safety outcomes.
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Date Issued: 2015
Identifier: CFE0005753, ucf:50097
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0005753

Title: MULTIOBJECTIVE COORDINATION MODELS FOR MAINTENANCE AND SERVICE PARTS INVENTORY PLANNING AND CONTROL.
Creator: Martinez, Oscar, Geiger, Christopher, University of Central Florida
Abstract / Description: In many equipment-intensive organizations in the manufacturing, service and particularly the defense sectors, service parts inventories constitute a significant source of tactical and operational costs and consume a significant portion of capital investment. For instance, the Defense Logistics Agency manages about 4 million consumable service parts and provides about 93% of all consumable service parts used by the military services. These items required about US$1.9 billion over the fiscal...
Show moreIn many equipment-intensive organizations in the manufacturing, service and particularly the defense sectors, service parts inventories constitute a significant source of tactical and operational costs and consume a significant portion of capital investment. For instance, the Defense Logistics Agency manages about 4 million consumable service parts and provides about 93% of all consumable service parts used by the military services. These items required about US$1.9 billion over the fiscal years 1999-2002. During the same time, the US General Accountability Office discovered that, in the United States Navy, there were about 3.7 billion ship and submarine parts that were not needed. The Federal Aviation Administration says that 26 million aircraft parts are changed each year. In 2002, the holding cost of service parts for the aviation industry was estimated to be US$50 billion. The US Army Institute of Land Warfare reports that, at the beginning of the 2003 fiscal year, prior to Operation Iraqi Freedom the aviation service parts alone was in excess of US$1 billion. This situation makes the management of these items a very critical tactical and strategic issue that is worthy of further study. The key challenge is to maintain high equipment availability with low service cost (e.g., holding, warehousing, transportation, technicians, overhead, etc.). For instance, despite reporting US$10.5 billion in appropriations spent on purchasing service parts in 2000, the United States Air Force (USAF) continues to report shortages of service parts. The USAF estimates that, if the investment on service parts decreases to about US$5.3 billion, weapons systems availability would range from 73 to 100 percent. Thus, better management of service parts inventories should create opportunities for cost savings caused by the efficient management of these inventories. Unfortunately, service parts belong to a class of inventory that continually makes them difficult to manage. Moreover, it can be said that the general function of service parts inventories is to support maintenance actions; therefore, service parts inventory policies are highly related to the resident maintenance policies. However, the interrelationship between service parts inventory management and maintenance policies is often overlooked, both in practice and in the academic literature, when it comes to optimizing maintenance and service parts inventory policies. Hence, there exists a great divide between maintenance and service parts inventory theory and practice. This research investigation specifically considers the aspect of joint maintenance and service part inventory optimization. We decompose the joint maintenance and service part inventory optimization problem into the supplier's problem and the customer's problem. Long-run expected cost functions for each problem that include the most common maintenance cost parameters and service parts inventory cost parameters are presented. Computational experiments are conducted for a single-supplier two-echelon service parts supply chain configuration varying the number of customers in the network. Lateral transshipments (LTs) of service parts between customers are not allowed. For this configuration, we optimize the cost functions using a traditional, or decoupled, approach, where each supply chain entity optimizes its cost individually, and a joint approach, where the cost objectives of both the supplier and customers are optimized simultaneously. We show that the multiple objective optimization approach outperforms the traditional decoupled optimization approach by generating lower system-wide supply chain network costs. The model formulations are extended by relaxing the assumption of no LTs between customers in the supply chain network. Similar to those for the no LTs configuration, the results for the LTs configuration show that the multiobjective optimization outperforms the decoupled optimization in terms of system-wide cost. Hence, it is economically beneficial to jointly consider all parties within the supply network. Further, we compare the model configurations – LTs versus no LTs, and we show that using LTs improves the overall savings of the system. It is observed that the improvement is mostly derived from reduced shortage costs since the equipment downtime is reduced due to the proximity of the supply. The models and results of this research have significant practical implications as they can be used to assist decision-makers to determine when and where to pre-position parts inventories to maximize equipment availability. Furthermore, these models can assist in the preparation of the terms of long-term service agreements and maintenance contracts between original equipment manufacturers and their customers (i.e., equipment owners and/or operators), including determining the equitable allocation of all system-wide cost savings under the agreement.
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Date Issued: 2008
Identifier: CFE0002459, ucf:47723
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0002459

Title: Internet of Things Business Modeling and Analysis using Agent-Based Simulation.
Creator: Basingab, Mohammed, Rabelo, Luis, Elshennawy, Ahmad, Lee, Gene, Rahal, Ahmad, University of Central Florida
Abstract / Description: Internet of Things (IoT) is a new vision of an integrated network covering physical objects that are able to collect and exchange data. It enables previously unconnected devices and objects to become connected using equipping devices with communication technology such as sensors and radio frequency identification tags (RFID). As technology progresses towards new paradigm such as IoT, there is a need for an approach to identify the significance of these projects. Conventional simulation...
Show moreInternet of Things (IoT) is a new vision of an integrated network covering physical objects that are able to collect and exchange data. It enables previously unconnected devices and objects to become connected using equipping devices with communication technology such as sensors and radio frequency identification tags (RFID). As technology progresses towards new paradigm such as IoT, there is a need for an approach to identify the significance of these projects. Conventional simulation modeling and data analysis approaches are not able to capture the system complexity or suffer from a lack of data needed that can help to build a prediction. Agent-based Simulation (ABM) proposes an efficient simulation scheme to capture the structure of this dimension and offer a potential solution.Two case studies were proposed in this research. The first one introduces a conceptual case study addressing the use of agent-based simulations to verify the effectiveness of the business model of IoT. The objective of the study is to assess the feasibility of such application, of the market in the city of Orlando (Florida, United States). The second case study seeks to use ABM to simulate the operational behavior of refrigeration units (7,420) in one of largest retail organizations in Saudi Arabia and assess the economic feasibility of IoT implementation by estimating the return on investment (ROI).
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Date Issued: 2017
Identifier: CFE0006855, ucf:51756
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0006855

Title: Control of Metal-Release and Tuberculation in a Silica-Laden Groundwater Distribution System on the Volcanic Island of Lana'i.
Creator: Myers, Samantha, Duranceau, Steven, Sadmani, A H M Anwar, Lee, Woo Hyoung, University of Central Florida
Abstract / Description: A corrosion control study for two distinct water distribution systems (WDS) has been completed for the Pulama Lana'i Water Company (Pulama). This project evaluated the use of chemical inhibitors to control corrosion and tuberculation within the Manele Bay WDS and the Lana'i City WDS. Pulama provides water to a population of 3,100 residents and is considering incorporating alternative water supplies in the future. Hence, knowing baseline corrosion rates within the WDS was desired.Several...
Show moreA corrosion control study for two distinct water distribution systems (WDS) has been completed for the Pulama Lana'i Water Company (Pulama). This project evaluated the use of chemical inhibitors to control corrosion and tuberculation within the Manele Bay WDS and the Lana'i City WDS. Pulama provides water to a population of 3,100 residents and is considering incorporating alternative water supplies in the future. Hence, knowing baseline corrosion rates within the WDS was desired.Several groundwater wells feed each of the WDS's; however, water quality between wells varies. Well water supplied to the WDS's is generally of high quality, therefore, the historical treatment method has been limited to disinfection prior to distribution. The distribution system consists of several materials of construction, which includes galvanized iron. Valves and pipes within the WDS were experiencing visible corrosion and tuberculation believed to be responsible for variable pressure drop throughout portions of the system.In this work, two corrosion racks, each consisting of two parallel loops, were designed, constructed, and installed at each site. One loop was maintained as a control while the other loop was used for testing alternative corrosion inhibitors. The racks utilized metal sample coupons and linear polarization resistance probes to provide data on corrosion rates of selected metals of interest.Results indicated that the water in Manele Bay experienced no noticeable change between the test loop and control loop when a corrosion inhibitor was added. A first experiment found the corrosion rates reached baseline steady(-)state at 4,000 operational hours. A second experiment found that the corrosion rates reached baseline steady(-)state at 2,200 operational hours. During these two experiments, the addition of a phosphate or silica(-)based inhibitor neither reduced nor increased the corrosion rates of mild steel, lead, and copper.Results from Lana'i City indicated that inhibitors offered little to no positive effect between the control condition and the test condition. During the first experiment, baseline corrosion was reached after 2,400 hours. The addition of a phosphate inhibitor did not reduce nor increase the corrosion rates of mild steel and lead. However, the corrosion rate of copper increased to 1.0mpy from 0.22mpy. The corrosion rate remained elevated after inhibitor feed was terminated. The second experiment reached baseline corrosion rates at 1,400 operational hours. The use of silica inhibitor neither reduced nor increased the corrosion rate of mil steel, lead, and copper.Since corrosion inhibitors were found to be ineffective, a valve exercise and replacement program for Pulama's assets was recommended. This program included: (1) developing a detailed asset inventory, (2) implementing operation and maintenance tasks, (3) forming a valve replacement plan, and (4) establishing long range financial planning. An opinion of probable replacement cost for 200 new valves was conceptually estimated to approximate 3.3 million dollars expended over a 20 year time frame.
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Date Issued: 2016
Identifier: CFE0006152, ucf:51152
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0006152

Title: Dog Ownership as a Catalyst of Conflict and Relationship Maintenance in Romantic Relationships.
Creator: Elrick, Ashley, Weger, Harry, Miller, Ann, Hastings, Sally, University of Central Florida
Abstract / Description: Pets are a common aspect of life for many Americans. In 2012, 36.5% of American household owned dogs and 30.4% owned cats (American Veterinary Medical Foundation, 2012). The purpose on this study was to explore the influence of dog ownership on romantic relationships. Specifically, this thesis investigates how dog ownership acts as a catalyst of relational maintenance and conflict behavior in interactions about the couple's dog. No prior research has been conducted on the role dogs' play in...
Show morePets are a common aspect of life for many Americans. In 2012, 36.5% of American household owned dogs and 30.4% owned cats (American Veterinary Medical Foundation, 2012). The purpose on this study was to explore the influence of dog ownership on romantic relationships. Specifically, this thesis investigates how dog ownership acts as a catalyst of relational maintenance and conflict behavior in interactions about the couple's dog. No prior research has been conducted on the role dogs' play in enacting relational maintenance or conflict in romantic relationships, so it is unclear if there is an influence to the these behaviors. This study asks how dog ownership might act as a centripetal force pulling the relationship together (e.g. relational maintenance) and/or as a centrifugal force pushing the partners apart (e.g. conflict). A total of 379 participants were recruited through social media to complete a short online survey. The survey asked questions on the romantic relationship, dog ownership, conflict regarding the dog, relational maintenance activities regarding the dog, and demographics. The majority of participants reported engaging in 8 of the 24 relational maintenance activities (")often(") or (")always(") and 3 of the 30 conflict topics occurred at least one or more times. Satisfaction with the romantic relationship associated positively with partial weak and negligible correlations to the relational maintenance activities and one negligible association with a conflict topic. A thematic analysis provides details on the short answers participants provided. The results shows that dogs do provide couples opportunities for relational maintenance but also are the source of conflict. This research is the start to understanding the role of dog ownership within romantic relationship. While each couple and dog may produce different influences on the relationship, this study is the start for the investigation and provides guidance for future research.
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Date Issued: 2014
Identifier: CFE0005328, ucf:50533
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0005328

Title: Autonomous Discovery and Maintenance of Mobile Frees-Space-Optical Links.
Creator: Khan, Mahmudur, Yuksel, Murat, Pourmohammadi Fallah, Yaser, Ewetz, Rickard, Turgut, Damla, Nam, Boo Hyun, University of Central Florida
Abstract / Description: Free-Space-Optical (FSO) communication has the potential to play a significant role in future generation wireless networks. It is advantageous in terms of improved spectrum utilization, higher data transfer rate, and lower probability of interception from unwanted sources. FSO communication can provide optical-level wireless communication speeds and can also help solve the wireless capacity problem experienced by the traditional RF-based technologies. Despite these advantages, communications...
Show moreFree-Space-Optical (FSO) communication has the potential to play a significant role in future generation wireless networks. It is advantageous in terms of improved spectrum utilization, higher data transfer rate, and lower probability of interception from unwanted sources. FSO communication can provide optical-level wireless communication speeds and can also help solve the wireless capacity problem experienced by the traditional RF-based technologies. Despite these advantages, communications using FSO transceivers require establishment and maintenance of line-of-sight (LOS). We consider autonomous mobile nodes (Unmanned Ground Vehicles or Unmanned Aerial Vehicles), each with one FSO transceiver mounted on a movable head capable of scanning in the horizontal and vertical planes. We propose novel schemes that deal with the problems of automatic discovery, establishment, and maintenance of LOS alignment between these nodes with mechanical steering of the directional FSO transceivers in 2-D and 3-D scenarios. We perform extensive simulations to show the effectiveness of the proposed methods for both neighbor discovery and LOS maintenance. We also present a prototype implementation of such mobile nodes with FSO transceivers. The potency of the neighbor discovery and LOS alignment protocols is evaluated by analyzing the results obtained from both simulations and experiments conducted using the prototype. The results show that, by using such mechanically steerable directional transceivers and the proposed methods, it is possible to establish optical wireless links within practical discovery times and maintain the links in a mobile setting with minimal disruption.
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Date Issued: 2018
Identifier: CFE0007575, ucf:52573
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0007575

Title: Integrating Spray Aeration and Granular Activated Carbon for Disinfection By-Product Control in a Potable Water System.
Creator: Rodriguez, Angela, Duranceau, Steven, Lee, Woo Hyoung, Sadmani, A H M Anwar, University of Central Florida
Abstract / Description: Public water systems add disinfectants in water treatment to inactivate microbial pathogens. Chlorine, when used as a disinfectant, reacts with natural organic matter in the water to form trihalomethane (THM) and haloacetic acid (HAA5) disinfection by-products (DBPs), which are suspected carcinogens. The Safe Drinking Water Act's Disinfectant and Disinfection By-Product (D/DBP) Rules were promulgated by the U.S. Environmental Protection Agency to regulate the amount of DBPs in water systems....
Show morePublic water systems add disinfectants in water treatment to inactivate microbial pathogens. Chlorine, when used as a disinfectant, reacts with natural organic matter in the water to form trihalomethane (THM) and haloacetic acid (HAA5) disinfection by-products (DBPs), which are suspected carcinogens. The Safe Drinking Water Act's Disinfectant and Disinfection By-Product (D/DBP) Rules were promulgated by the U.S. Environmental Protection Agency to regulate the amount of DBPs in water systems. Regulatory compliance is based on maximum contaminant levels (MCL), measured as a locational running annual average (LRAA), for total THM (TTHM) and HAA5 of 80 (&)#181;g/L and 60 (&)#181;g/L, respectively. Regulated DBPs, if consumed in excess of EPA's MCL standard over many years, may increase chronic health risks. In order to comply with the D/DBP Rules, the County of Maui Department of Water Supply (DWS) adopted two DBP control technologies. A GridBee(&)#174; spray-aeration process was place into DWS's Lower Kula water system's Brooks ground storage tank in February of 2013. In March of 2015 the second DBP control technology, granular activated carbon (GAC), was integrated into DWS's Pi'iholo surface water treatment plant. To investigate the integration effectiveness of GAC and spray-aeration into a water system for DBP control, DBP data was gathered from the system between August of 2011 and August 2016, and analyzed relative to cost and performance.Prior to the spray aeration and GAC integration, it was found that TTHM levels at the LRAA compliance site ranged between 58.5 (&)#181;g/L and 125 (&)#181;g/L (at times exceeding the MCL). Additionally, HAA5 levels at the LRAA compliance site ranged between 21.2 and 52.0 (&)#181;g/L. The concerted efforts of the GAC and GridBee(&)#174; system was found to reduce LRAA TTHM and HAA5 concentrations to 38.5 (&)#181;g/L and 20.5 (&)#181;g/L, respectively, in the Lower Kula system. Hypothesis testing utilizing t-Tests confirmed that TTHMs levels were controlled by the spray aeration system and the GAC was responsible for controlling HAA5 formation. Although TTHM levels were reduced by 58 percent, and HAA5 levels by 48 percent, the estimated cumulative annual operation and maintenance (O(&)M) cost of the two systems was $1,036,000. In light of the cost analysis, total organic carbon (TOC)-based models for predicting LRAA TTHM and HAA5 levels were developed as equation (i) and (ii), respectively:(i) TTHM (&)#181;g/L = (32.5 x (TOC ppm)) + 5.59, (ii) HAA5 (&)#181;g/L = (8.37 x (TOC ppm)) + 12.4.The TTHM model yielded an R2 of 0.93, and the HAA5 model had an R2 of 0.52. F-Tests comparing predicted LRAA TTHM and HAA5 levels to actual LRAA TTHM and HAA5 levels determined no statistically-significant difference. With the knowledge of how the GAC and spray aerator controlled DBPs in the water system, a cost-effective and practical treatment operating parameter was developed. The parameter, Pi'iholo water plant filter effluent TOC content, can serve as an indicator that operators would use to alter DBP treatment process flow set points to achieve cost-effective treatment. Furthermore, the significant annual cost contribution by the GAC, coupled with HAA5 levels below DWS's MCLG, led to the recommendation of variable frequency drive (VFD) pumps for the GAC system. The addition of VFD pumps should reduce the frequency of carbon change outs while preserving adequate HAA5 control in the system.
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Date Issued: 2016
Identifier: CFE0006841, ucf:52881
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0006841

maintenance (2)	+ -
Agent-Based Simulation (1)	+ -
Ambulatory medical care -- Florida (1)	+ -
Autonomous (1)	+ -
Children of Divorce (1)	+ -

Communication (1)	+ -
Conflict (1)	+ -
Disinfection By-Products (DBPs) (1)	+ -
Distribution System Management (1)	+ -
Dog Ownership (1)	+ -
Drinking Water (1)	+ -
Drones (1)	+ -
Free-Space-Optical Communication (1)	+ -
Government aircraft (1)	+ -
Granular Activated Carbon (GAC) (1)	+ -
HVAC systems (1)	+ -
Health maintenance organizations -- Florida (1)	+ -
Helicopters -- Maintenance and repair (1)	+ -
Internet of Things (1)	+ -
Line-of-Sight (1)	+ -
Link Maintenance (1)	+ -
Logistics (1)	+ -
Mobile (1)	+ -
Neighbor Discovery (1)	+ -
Operation and maintenance (O&M) Cost (1)	+ -
Parental Divorce (1)	+ -
Pets (1)	+ -
Predictive Analytics (1)	+ -
Predictive Maintenance (1)	+ -
Relational Maintenance (1)	+ -

ETD Collection (12)	+ -
Honors Collection (1)	+ -

University of Central Florida (11)	+ -
Duranceau, Steven (2)	+ -
Lee, Woo Hyoung (2)	+ -
Sadmani, A H M Anwar (2)	+ -
Alnoaimi, Muhanna (1)	+ -

Basingab, Mohammed (1)	+ -
Doering, R. D. (1)	+ -
Elrick, Ashley (1)	+ -
Elshennawy, Ahmad (1)	+ -
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