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Title: Evaluation and Modeling of the Safety of Open Road Tolling System.
Creator: Abuzwidah, Muamer, Abdel-Aty, Mohamed, Radwan, Ahmed, Uddin, Nizam, University of Central Florida
Abstract / Description: The goal of this thesis is to examine the traffic safety impact of upgrading Toll Plazas (TP) to Open Road Tolling (ORT). The ORT could enhance safety but could also pose some traffic safety concerns at Toll plazas. Crashes from eight years were investigated by evaluating the crash data before and after the implementation of the ORT.The study was conducted by using two approaches: 1) a simple before and after study and with a comparison group; 2) a modeling effort to help understand the...
Show moreThe goal of this thesis is to examine the traffic safety impact of upgrading Toll Plazas (TP) to Open Road Tolling (ORT). The ORT could enhance safety but could also pose some traffic safety concerns at Toll plazas. Crashes from eight years were investigated by evaluating the crash data before and after the implementation of the ORT.The study was conducted by using two approaches: 1) a simple before and after study and with a comparison group; 2) a modeling effort to help understand the relationship between the crash frequency and several important factors and circumstances such as injury severity, collision types, average daily traffic (ADT) and Toll plaza characteristics. The study investigated 11 Toll plazas on State Roads 408, 417, 528 and 429 that have been changed to the ORT design. Several maps showing the Toll plazas and identifying the relevant crash locations were generated. Negative Binomial (NB), Log Linear model and two-way contingency table were examined. Two log-linear models with three variables in each model with all possible two-way interactions were developed. Categorical data analysis of the 2009 and 2010 crash dataset was performed. In order to compare the differences in response between the crash frequency and a particular crash-related variable, odds ratios were computed. The effects of crash frequency and crash-related factors were examined, and interactions among them were considered. The results indicated significant relationships between the crash frequency and ADT, crash type and driver age.It is worth mentioning that the expressway network understudy was continuously experiencing constructions throughout the study period. There is indication that ORT reduced the total crash number; also there is indication of changing the crash types and locations; and the majority of crashes occurred at the diverging and merging areas and resulted in more severe crashes. More data may be needed to confirm these results especially after all constructions and upgrades are made.The Implementation of open road tolling, the locations of Toll plazas, Automatic Vehicle Identification (AVI) subscription rate, traffic demand, and plaza geometry all may have a high influence on traffic safety concerns at Toll plazas, as concluded from the negative Binomial Model's results. The changing of sign locations, reducing the speed limit, installing variable message signs, configuring plazas properly, and other considerations may be the solution to overcome the potential safety problems in the vicinity of Toll plazas.The change of design to ORT was proven to be an excellent solution to several traffic operation problems, including reducing congestion and improving traffic flow and capacity at Toll plazas. However, addressing safety concerns at Toll plazas should take priority.
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Date Issued: 2011
Identifier: CFE0004466, ucf:49330
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0004466

Title: STATISTICAL ANALYSIS OF DEPRESSION AND SOCIAL SUPPORT CHANGE IN ARAB IMMIGRANT WOMEN IN USA.
Creator: Blbas, Hazhar, Uddin, Nizam, Nickerson, David, Aroian, Karen, University of Central Florida
Abstract / Description: Arab Muslim immigrant women encounter many stressors and are at risk for depression. Social supports from husbands, family and friends are generally considered mitigating resources for depression. However, changes in social support over time and the effects of such supports on depression at a future time period have not been fully addressed in the literature This thesis investigated the relationship between demographic characteristics, changes in social support, and depression in Arab Muslim...
Show moreArab Muslim immigrant women encounter many stressors and are at risk for depression. Social supports from husbands, family and friends are generally considered mitigating resources for depression. However, changes in social support over time and the effects of such supports on depression at a future time period have not been fully addressed in the literature This thesis investigated the relationship between demographic characteristics, changes in social support, and depression in Arab Muslim immigrant women to the USA. A sample of 454 married Arab Muslim immigrant women provided demographic data, scores on social support variables and depression at three time periods approximately six months apart. Various statistical techniques at our disposal such as boxplots, response curves, descriptive statistics, ANOVA and ANCOVA, simple and multiple linear regressions have been used to see how various factors and variables are associated with changes in social support from husband, extended family and friend over time. Simple and multiple regression analyses are carried out to see if any variable observed at the time of first survey can be used to predict depression at a future time. Social support from husband and friend, husband's employment status and education, and depression at time one are found to be significantly associated with depression at time three. Finally, logistic regression analysis conducted for a binary depression outcome variable indicated that lower total social support and higher depression score of survey participants at the time of first survey increase their probability of being depressed at the time of third survey.
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Date Issued: 2014
Identifier: CFE0005133, ucf:50676
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0005133

Title: The effect of Building Information Modeling on Design and Construction Industry.
Creator: Alassaf, Yahya, Oloufa, Amr, Tatari, Omer, Uddin, Nizam, Mouloua, Mustapha, University of Central Florida
Abstract / Description: Construction industry's evolution is, historically, in the lowest level, if compared to other industries, such as auto manufacturing. Construction is a multidisciplinary industry, considering that designers, contractors, and owners are all involved in the same project, each one seeking their own interests. The complex environment surrounding design and construction makes the decision-makers hesitate about adopting new methodology. Building Information Modeling (BIM) is a new method and...
Show moreConstruction industry's evolution is, historically, in the lowest level, if compared to other industries, such as auto manufacturing. Construction is a multidisciplinary industry, considering that designers, contractors, and owners are all involved in the same project, each one seeking their own interests. The complex environment surrounding design and construction makes the decision-makers hesitate about adopting new methodology. Building Information Modeling (BIM) is a new method and technology, which can improve both the design and the construction processes. The adoption of BIM is increasing significantly over the last years, and its effects can be seen on real life projects. In order to understand the effect of BIM on the design and construction industry, we have created a comprehensive survey, consisting of a general questionnaire and experts' interviews. The general questionnaire concentrated on most of BIM issues, while the interviews focused on specific points arisen from the general questionnaire. Most of the published papers in this area justify BIM adoption by focusing on BIM ROI, and the comparison between project with and without BIM. In this research, however, we tried first to understand BIM status at the AEC market, and then to measure its effects. Therefore, we have targeted all the players in the BIM field: engineers, architects, contractors, and owners. Through the general questionnaire, we have measured the relationship between the independent variables and outcome variables. The independent variables are: motivations, concerns, investment needed, software, valuable benefits, success measures, and BIM uses. The outcome variables include: companies' role, sector, specialty, market level, level of implementation, years of implementation, and experience. In the second part of the research, we have conducted a series of subject matter interviews to measure the effect of BIM uses and its intangible benefits. For the experts' interviews, we designed a structured interview which covers two major areas: BIM uses, and intangible benefits. Both areas derived from the general questionnaire, and we aimed to measure their effects on real life projects. After analyzing the general questionnaire by using Person Chi-Square test, the results shown a significant relationship between independent variables and outcome variables. Participants' responses shown that they share common objectives when establishing BIM such as: increasing communication, reducing rework, increasing coordination and collaboration between parties, improving quality, and increasing productivity. We have found that the use of BIM is varied, and the large companies are taking advantage of BIM technology. In addition, the majority of the participants indicate that BIM has a positive ROI, and its adoption generates more business. The experts' interviews uncovered the fact that AEC parties have common understanding about the intangible benefits, even though they perceive the benefits differently. The diverse views of intangibles' benefits were influenced by the distinct role of each party. Moreover, experts share information about BIM project, and the project outcomes are successful on the following metrics: cost, schedule, number of RFI, number of change orders, and quality.
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Date Issued: 2016
Identifier: CFE0006432, ucf:51486
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0006432

Title: Wrong-Way Driving: A Regional Approach To A Regional Problem.
Creator: Faruk, Md. Omar, Al-Deek, Haitham, Uddin, Nizam, Hasan, Samiul, University of Central Florida
Abstract / Description: Wrong-way driving (WWD) has been problematic on United States highways for decades despite its rare occurrence. Since WWD crashes are rare, recent researchers have studied WWD non-crash events such as WWD 911 calls and WWD citations to understand the overall nature and trend of WWD. This paper demonstrates the regional nature of the WWD problem and proposes regional transportation systems management and operations (Regional TSM(&)O) solutions to combat this problem. Specifically, it was found...
Show moreWrong-way driving (WWD) has been problematic on United States highways for decades despite its rare occurrence. Since WWD crashes are rare, recent researchers have studied WWD non-crash events such as WWD 911 calls and WWD citations to understand the overall nature and trend of WWD. This paper demonstrates the regional nature of the WWD problem and proposes regional transportation systems management and operations (Regional TSM(&)O) solutions to combat this problem. Specifically, it was found that 11% of all WWD multi-data events (e.g., multiple 911 calls for the same WWD event) traveled from one county to another. Additionally, 30% of all WWD single-data and multi-data events occurred at or near interchanges between two limited access highways in counties with multiple operating agencies. This indicates that a significant proportion of WWD events could potentially travel from one limited access facility to another. Moreover, 28% of WWD events occurred on limited access facilities shared by multiple agencies. To emphasize the regional nature of WWD, this paper determined the vulnerable demographic groups in different regions of Florida by developing WWD crash and citation prediction models. The models' findings indicate that certain demographic groups (such as elderly or Hispanic) increase WWD risk. The models' results can be used to improve driver education and increase law enforcement presence in high risk WWD locations. Regional TSM(&)O solutions, such as coordination and communication among agencies and regional traffic management centers (RTMCs), law enforcement co-location with RTMCs, and strengthening statewide TSM(&)O programs to manage WWD events are also proposed.
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Date Issued: 2017
Identifier: CFE0006874, ucf:51736
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0006874

Title: The Effect of Habitat for Humanity Homeownership on Student Attendance and Standardized Test Scores in Orange County Florida School District.
Creator: Harris, Charles, Kincaid, John, Uddin, Nizam, Rivers, Kenyatta, Wiegand, Rudolf, University of Central Florida
Abstract / Description: The mobility of low-income students who do not have access to stable housing creates numerous challenges both at home and in school. Among these challenges, academic performance certainly is one of the most important. The lack of a more permanent, familiar, and safe environment is presumed to impact home life as well as students' performance in the classroom. This research compares two groups of current and former students of Orange County Public Schools (OCPS) in Florida (1) children of...
Show moreThe mobility of low-income students who do not have access to stable housing creates numerous challenges both at home and in school. Among these challenges, academic performance certainly is one of the most important. The lack of a more permanent, familiar, and safe environment is presumed to impact home life as well as students' performance in the classroom. This research compares two groups of current and former students of Orange County Public Schools (OCPS) in Florida (1) children of families who are Habitat for Humanity (HFH) homeowners, and (2) a matched socioeconomic control group. The HFH program is designed to provide a stable, affordable housing for families who cannot acquire it through standard means. The research question is: Does stability in housing make an impact on academic performance in the particular area of FCAT scores and attendance? Data were gathered from OCPS and the HFH homeowners themselves. This data were used to evaluate the impact of HFH homeownership on students' academic environment. Results showed better attendance at school, but HFH students fared worse in FCAT performance when compared to control group especially in reading.
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Date Issued: 2014
Identifier: CFE0005504, ucf:50360
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0005504

Title: Sparse Ridge Fusion For Linear Regression.
Creator: Mahmood, Nozad, Maboudou, Edgard, Schott, James, Uddin, Nizam, University of Central Florida
Abstract / Description: For a linear regression, the traditional technique deals with a case where the number of observations n more than the number of predictor variables p (n(>)p). In the case n(
Show moreFor a linear regression, the traditional technique deals with a case where the number of observations n more than the number of predictor variables p (n(>)p). In the case n(<)p, the classical method fails to estimate the coefficients. A solution of this problem in the case of correlated predictors is provided in this thesis. A new regularization and variable selection is proposed under the name of Sparse Ridge Fusion (SRF). In the case of highly correlated predictor , the simulated examples and a real data show that the SRF always outperforms the lasso, elastic net, and the S-Lasso, and the results show that the SRF selects more predictor variables than the sample size n while the maximum selected variables by lasso is n size.
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Date Issued: 2013
Identifier: CFE0005031, ucf:49997
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0005031

Title: How many are out there? A novel approach for open and closed systems.
Creator: Rehman, Zia, Kincaid, John, Wiegand, Rudolf, Finch, Craig, Uddin, Nizam, University of Central Florida
Abstract / Description: We propose a ratio estimator to determine population estimates using capture-recapture sampling. It's different than traditional approaches in the following ways:(1)Ordering of recaptures: Currently data sets do not take into account the "ordering" of the recaptures, although this crucial information is available to them at no cost. (2)Dependence of trials and cluster sampling: Our model explicitly considers trials to be dependent and improves existing literature which assumes independence. ...
Show moreWe propose a ratio estimator to determine population estimates using capture-recapture sampling. It's different than traditional approaches in the following ways:(1)Ordering of recaptures: Currently data sets do not take into account the "ordering" of the recaptures, although this crucial information is available to them at no cost. (2)Dependence of trials and cluster sampling: Our model explicitly considers trials to be dependent and improves existing literature which assumes independence. (3)Rate of convergence: The percentage sampled has an inverse relationship with population size, for a chosen degree of accuracy. (4)Asymptotic Attainment of Minimum Variance (Open Systems: (=population variance).(5)Full use of data and model applicability (6)Non-parametric (7)Heterogeneity: When units being sampled are hard to identify. (8)Open and closed systems: Simpler results are presented separately for closed systems.(9)Robustness to assumptions in open systems
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Date Issued: 2014
Identifier: CFE0005403, ucf:50411
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0005403

Title: TRAFFIC SAFETY ASSESSMENT OF DIFFERENT TOLL COLLECTION SYSTEMS ON EXPRESSWAYS USING MULTIPLE ANALYTICAL TECHNIQUES.
Creator: Abuzwidah, Muamer, Abdel-Aty, Mohamed, Radwan, Essam, Uddin, Nizam, University of Central Florida
Abstract / Description: Traffic safety has been considered one of the most important issues in the transportation field. Crashes have caused extensive human and economic losses. With the objective of reducing crash occurrence and alleviating crash injury severity, major efforts have been dedicated to reveal the hazardous factors that affect crash occurrence. With these consistent efforts, both fatalities and fatality rates from road traffic crashes in many countries have been steadily declining over the last ten...
Show moreTraffic safety has been considered one of the most important issues in the transportation field. Crashes have caused extensive human and economic losses. With the objective of reducing crash occurrence and alleviating crash injury severity, major efforts have been dedicated to reveal the hazardous factors that affect crash occurrence. With these consistent efforts, both fatalities and fatality rates from road traffic crashes in many countries have been steadily declining over the last ten years. Nevertheless, according to the World Health Organization, the world still lost 1.24 million lives from road traffic crashes in the year of 2013. And without action, traffic crashes on the roads network are predicted to result in deaths of around 1.9 million people, and up to 50 million more people suffer non-fatal injuries annually, with many incurring a disability as a result of their injury by the year 2020. To meet the transportation needs, the use of expressways (toll roads) has risen dramatically in many countries in the past decade. In fact, freeways and expressways are considered an important part of any successful transportation system. These facilities carry the majority of daily trips on the transportation network. Although expressways offer high level of service, and are considered the safest among other types of roads, traditional toll collection systems may have both safety and operational challenges. The traditional toll plazas still experience many crashes, many of which are severe. Therefore, it becomes more important to evaluate the traffic safety impacts of using different tolling systems. The main focus of the research in this dissertation is to provide an up-to-date safety impact of using different toll collection systems, as well as providing safety guidelines for these facilities to promote safety and enhance mobility on expressways. In this study, an extensive data collection was conducted that included one hundred mainline toll plazas located on approximately 750 miles of expressways in Florida. Multiple sources of data available online maintained by Florida Department of Transportation were utilized to identify traffic, geometric and geographic characteristics of the locations as well as investigating and determination of the most complete and accurate data. Different methods of observational before-after and Cross-Sectional techniques were used to evaluate the safety effectiveness of applying different treatments on expressways. The Before-After method includes Na(&)#239;ve Before-After, Before-After with Comparison Group, and Before-After with Empirical Bayesian. A set of Safety Performance Functions (SPFs) which predict crash frequency as a function of explanatory variables were developed at the aggregate level using crash data and the corresponding exposure and risk factors. Results of the aggregate traffic safety analysis can be used to identify the hazardous locations (hot spots) such as traditional toll plazas, and also to predict crash frequency for untreated sites in the after period in the Before-After with EB method or derive Crash Modification Factors (CMF) for the treatment using the Cross-Sectional method. This type of analysis is usually used to improve geometric characteristics and mainly focus on discovering the risk factors that are related to the total crash frequency, specific crash type, and/or different crash severity levels. Both simple SPFs (with traffic volume only as an explanatory variable) and full SPFs (with traffic volume and additional explanatory variable(s)) were used to estimate the CMFs and only CMFs with lower standard error were recommended.The results of this study proved that safety effectiveness was significantly improved across all locations that were upgraded from Traditional Mainline Toll Plazas (TMTP) to the Hybrid Mainline Toll Plazas (HMTP) system. This treatment significantly reduced total, Fatal-and-Injury (F+I), and Rear-End crashes by 47, 46 and 65 percent, respectively. Moreover, this study examined the traffic safety impact of using different designs, and diverge-and-merge areas of the HMTP. This design combines either express Open Road Tolling (ORT) lanes on the mainline and separate traditional toll collection to the side (design-1), or traditional toll collection on the mainline and separate ORT lanes to the side (design-2). It was also proven that there is a significant difference between these designs, and there is an indication that design-1 is safer and the majority of crashes occurred at diverge-and-merge areas before and after these facilities. However, design-2 could be a good temporary design at locations that have low prepaid transponder (Electronic Toll Collection (ETC)) users. In other words, it is dependent upon the percentage of the ETC users. As this percentage increases, more traffic will need to diverge and merge; thus, this design becomes riskier. In addition, the results indicated significant relationships between the crash frequency and toll plaza types, annual average daily traffic, and drivers' age. The analysis showed that the conversion from TMTP to the All-Electronic Toll Collection (AETC) system resulted in an average reduction of 77, 76, and 67 percent for total, F+I, and Property Damage Only (PDO) crashes, respectively; for rear end and Lane Change Related (LCR) crashes the average reductions were 81 and 75 percent, respectively. The conversion from HMTP to AETC system enhanced traffic safety by reducing crashes by an average of 23, 29 and 19 percent for total, F+I, and PDO crashes; also, for rear end and LCR crashes, the average reductions were 15 and 21 percent, respectively. Based on these results, the use of AETC system changed toll plazas from the highest risk sections on Expressways to be similar to regular segments. Therefore, it can be concluded that the use of AETC system was proven to be an excellent solution to several traffic operations as well as environmental and economic problems. For those agencies that cannot adopt the HMTP and the AETC systems, improving traffic safety at traditional toll plazas should take a priority.This study also evaluates the safety effectiveness of the implementation of High-Occupancy Toll lanes (HOT Lanes) as well as adding roadway lighting to expressways. The results showed that there were no significant impact of the implementation of HOT lanes on the roadway segment as a whole (HOT and Regular Lanes combined). But there was a significant difference between the regular lanes and the HOT lanes at the same roadway segment; the crash count increased at the regular lanes and decreased at the HOT lanes. It was found that the total and F+I crashes were reduced at the HOT lanes by an average of 25 and 45 percent, respectively. This may be attributable to the fact that the HOT lanes became a highway within a highway. Moreover adding roadway lighting has significantly improved traffic safety on the expressways by reducing the night crashes by approximately 35 percent.Overall, the proposed analyses of the safety effectiveness of using different toll collection systems are useful in providing expressway authorities with detailed information on where countermeasures must be implemented. This study provided for the first time an up-to-date safety impact of using different toll collection systems, also developed safety guidelines for these systems which would be useful for practitioners and roadway users.
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Date Issued: 2014
Identifier: CFE0005751, ucf:50100
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0005751

Title: Modeling of Wrong Way Driving Entries and Developing Innovative Approaches for Evaluating the Effectiveness of Advanced Wrong Way Driving Countermeasures.
Creator: Kayes, Md Imrul, Al-Deek, Haitham, Eluru, Naveen, Hasan, Samiul, Uddin, Nizam, University of Central Florida
Abstract / Description: Wrong-way driving (WWD) is a hazardous behavior on interstates, toll roads, and other high-speed limited access facilities. Since WWD crashes are rare, recent researchers have studied WWD events such as WWD 911 calls and WWD citations to understand the overall nature and trend of WWD. It is very difficult to build credible statistical models based solely on crashes due to the small sample size since these are only 3% of all crashes. Modeling of WWD non-crash events can result in more accurate...
Show moreWrong-way driving (WWD) is a hazardous behavior on interstates, toll roads, and other high-speed limited access facilities. Since WWD crashes are rare, recent researchers have studied WWD events such as WWD 911 calls and WWD citations to understand the overall nature and trend of WWD. It is very difficult to build credible statistical models based solely on crashes due to the small sample size since these are only 3% of all crashes. Modeling of WWD non-crash events can result in more accurate models. A model was developed for Florida limited access facilities to identify roadway factors and traffic characteristics of exit ramp terminals that influence WWD entries. This model indicated that interchange type, intersection angle of exit ramp terminals, presence of tolling at the entrance ramp, presence of channelizing island between the exit ramp lanes, number of lanes on the exit ramp, area (rural or urban), and traffic volumes significantly affect the likelihood of WWD entries at exit ramps. Conventional (")Wrong Way(") signs can reduce WWD incidents but can be insufficient in some cases. In areas with many WWD crash and non-crash events, transportation agencies can be proactive by considering the use of countermeasures with advanced technologies to actively warn motorists of WWD violations. To help agencies select the most effective countermeasure, two innovative evaluation of performance approaches were developed so they can be used to evaluate and compare among different advanced WWD countermeasures. These approaches consist of before-after analysis of WWD non-crash events (WWD 911 calls and citations) and turn around rates of wrong way vehicles to self-correct their WWD acts. With this research, transportation agencies can better predict WWD entries at exit ramps; identify suitable locations for possible countermeasures deployment; and improve their current design, signing, and pavement marking practices while still following national and state standards.
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Date Issued: 2019
Identifier: CFE0007474, ucf:52672
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0007474

Title: Understanding How, Where and How much Freight Flows Using 2012 Commodity Flow Survey Data.
Creator: Keya, Nowreen, Eluru, Naveen, Abdel-Aty, Mohamed, Anowar, Sabreena, Uddin, Nizam, University of Central Florida
Abstract / Description: In recent years, with increased economic globalization, growing e-commerce and internet based shopping, freight movement patterns are undergoing a transformative change. The shipment size distribution is moving towards a higher share of smaller size shipments affecting transportation mode and vehicle type requirements. In addition, freight transportation mode is closely affected by the destination location (and its attributes). In our dissertation, we contribute to freight research by...
Show moreIn recent years, with increased economic globalization, growing e-commerce and internet based shopping, freight movement patterns are undergoing a transformative change. The shipment size distribution is moving towards a higher share of smaller size shipments affecting transportation mode and vehicle type requirements. In addition, freight transportation mode is closely affected by the destination location (and its attributes). In our dissertation, we contribute to freight research by developing a comprehensive framework to examine the how, where and how much freight flows in US. Specifically, we study the following dimensions of freight flow: (1) transportation mode, (2) mode and shipment weight choice and (3) mode and destination choice. For analyzing mode choice, an advanced discrete freight mode choice model- a hybrid utility-regret based model system has been estimated while accommodating for shipper level unobserved heterogeneity. To demonstrate the applicability of the proposed model system, detailed policy analyses examining the implementation of vehicle fleet automation and rerouting of freight movements away from a region were considered. While shipment weight could be considered as an explanatory variable in modeling mode choice (or vice-versa), it is more likely that the decision of mode and shipment choice is a simultaneous process. This joint decision is investigated both simultaneously employing a closed form copula structure and sequentially employing latent segmentation based sequence model. For destination choice, we investigated the connection between shipping mode and destination choice of shipment in a latent segmentation based sequential form. The analysis for the dissertation is conducted using 2012 Commodity Flow Survey (CFS) data.
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Date Issued: 2018
Identifier: CFE0007574, ucf:52569
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0007574

Title: Stress, Coping, and Quality of Life Among Parental Caregivers of Children with Autism Spectrum Disorder.
Creator: Turnage, Dawn, Conner, Norma, Edwards, Joellen, Weiss, Josie, Hinojosa, Melanie, Uddin, Nizam, University of Central Florida
Abstract / Description: Purpose: Parental caregivers of children with Autism Spectrum Disorder (ASD) are exposed to stressors associated with the daily care of raising a child with a developmental disability, which may negatively impact parental quality of life (QOL). The specific aim of this study was to examine the relationships between demographic factors, stress, and coping among parental caregivers of children with ASD to determine whether predictors of QOL exist. Methodology: This study was descriptive, and an...
Show morePurpose: Parental caregivers of children with Autism Spectrum Disorder (ASD) are exposed to stressors associated with the daily care of raising a child with a developmental disability, which may negatively impact parental quality of life (QOL). The specific aim of this study was to examine the relationships between demographic factors, stress, and coping among parental caregivers of children with ASD to determine whether predictors of QOL exist. Methodology: This study was descriptive, and an electronic survey was distributed to Florida parents of children, age 3-21 years old, diagnosed with ASD. The survey measured parentreported demographic factors, severity of the diagnosis of ASD in the child, parental stress, coping, and QOL. Data were analyzed using multiple regression. Findings: Study findings suggest that, in parental caregivers of children with ASD in Florida (N = 152) daily stressors, coping self-efficacy, and household income were predictors for physical QOL; daily stressors and coping self-efficacy were predictors of psychological QOL, and coping-self efficacy, household income, and severity of the diagnosis of the child were predictors for environmental QOL. Conclusion: Coping self-efficacy and improved income can positively improve QOL, while severity of the diagnosis of ASD and daily stressors can negatively impact QOL. Clinically, nurses with a better understanding of the parental stress and coping in parents of children with ASD can better recommend tailored resources to improve QOL. Policies to support financial help for families may also improve QOL. Future research should focus on interventions to improve coping-self efficacy.
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Date Issued: 2019
Identifier: CFE0007737, ucf:52412
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0007737

Title: A Framework for Quantifying Sustainability of Lean Implementation in Healthcare Organizations.
Creator: Bahaitham, Haitham, Elshennawy, Ahmad, Mollaghasemi, Mansooreh, Lee, Gene, Uddin, Nizam, Furterer, Sandra, University of Central Florida
Abstract / Description: Due to the remarkable positive effect of lean adoption in various firms in the manufacturing sector, it has been adopted by several organizations within the healthcare industry. Although the rate of adopting lean by hospitals in the developed countries is slower than it should be, it proved to be effective in helping healthcare organizations maintain or even improve their quality of care while containing their related costs. However, such adoption did not take place until the beginning of the...
Show moreDue to the remarkable positive effect of lean adoption in various firms in the manufacturing sector, it has been adopted by several organizations within the healthcare industry. Although the rate of adopting lean by hospitals in the developed countries is slower than it should be, it proved to be effective in helping healthcare organizations maintain or even improve their quality of care while containing their related costs. However, such adoption did not take place until the beginning of the new millennium. And with such adoption, it has been accompanied with major challenges related to proper lean implementation, sustainability of achieved levels of performance, and staff engagement in infinite cycles of continuous improvement towards perfection. Thus, the purpose of this study is to develop a framework that helps healthcare organizations quantify their experience with lean. Such quantification is obtained by measuring the agreement level of hospital staff members about the degree of adopting two sets of critical factors of successful lean implementation within their hospital. These two sets of factors are classified as process factors and organizational factors. The proposed framework has been validated by determining the sustainability level of lean implementation within one of U.S. hospitals in the State of Florida. The developed framework provides a balanced assessment of both process and organizational factors essential for achieving sustainable levels of lean implementation. In order to accommodate for the observed variation in lean adoption in hospitals, individual hospital departments are considered the (")analysis units(") of the developed framework. In order to quantify the implementation status of lean within a hospital department, a survey-based lean sustainability assessment tool has been developed based on the defined sets of factors. The sustainability level of lean implementation of a hospital can be obtained by combining various responses of its surveyed departments. The developed framework is the first that addresses both process and organizational factors of sustainable lean implementation in a balanced manner while fulfilling the assessment needs of all healthcare organizations regardless of their current level of lean adoption. In addition, utilizing the framework within a hospital enhances employee involvement and respect for employee which are essential for sustainable lean implementation. Finally, the developed framework provides healthcare supervising authorities (i.e. ministries of health or corporate offices of hospitals' groups) a macro-level benchmarking view regarding the progress of their hospitals towards implementing sustainable levels of lean.
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Date Issued: 2011
Identifier: CFE0004086, ucf:49140
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0004086

Title: Macroscopic Crash Analysis and Its Implications for Transportation Safety Planning.
Creator: Siddiqui, Chowdhury, Abdel-Aty, Mohamed, Abdel-Aty, Mohamed, Uddin, Nizam, Huang, Helai, University of Central Florida
Abstract / Description: Incorporating safety into the transportation planning stage, which is often termed as transportation safety planning (TSP), relies on the vital interplay between zone characteristics and zonal traffic crashes. Although a few safety studies had made some effort towards integrating safety and planning, several unresolved problems and a complete framework of TSP are still absent in the literature. This research aims at examining the suitability of the current traffic-related zoning planning...
Show moreIncorporating safety into the transportation planning stage, which is often termed as transportation safety planning (TSP), relies on the vital interplay between zone characteristics and zonal traffic crashes. Although a few safety studies had made some effort towards integrating safety and planning, several unresolved problems and a complete framework of TSP are still absent in the literature. This research aims at examining the suitability of the current traffic-related zoning planning process in a new suggested planning method which incorporates safety measures. In order to accomplish this broader research goal, the study defined its research objectives in the following directions towards establishing a framework of TSP- i) exploring the existing key determinants in traditional transportation planning (e.g., trip generation/distribution data, land use types, demographics, etc.) in order to develop an effective and efficient TSP framework, ii) investigation of the Modifiable Aerial Unit Problem (MAUP) in the context of macro-level crash modeling to investigate the effect of the zone's size and boundary, iii) understanding neighborhood influence of the crashes at or near zonal boundaries, and iv) development of crash-specific safety measure in the four-step transportation planning process.This research was conducted using spatial data from the counties of West Central Florida. Analysis of different crash data per spatial unit was performed using nonparametric approaches (e.g., data mining and random forest), classical statistical methods (e.g., negative binomial models), and Bayesian statistical techniques. In addition, a comprehensive Geographic Information System (GIS) based application tools were utilized for spatial data analysis and representation.Exploring the significant variables related to specific types of crashes is vital in the planning stages of a transportation network. This study identified and examined important variables associated with total crashes and severe crashes per traffic analysis zone (TAZ) by applying nonparametric statistical techniques using different trip related variables and road-traffic related factors. Since a macro-level analysis, by definition, will necessarily involve aggregating crashes per spatial unit, a spatial dependence or autocorrelation may arise if a particular variable of a geographic region is affected by the same variable of the neighboring regions. So far, few safety studies were performed to examine crashes at TAZs and none of them explicitly considered spatial effect of crashes occurring in them. In order to understand the clear picture of spatial autocorrelation of crashes, this study investigated the effect of spatial autocorrelation in modeling pedestrian and bicycle crashes in TAZs. Additionally, this study examined pedestrian crashes at Environmental Justice (EJ) TAZs which were identified in compliance with the various ongoing practices undertaken by Metropolitan Planning Organizations (MPOs) and previous research. Minority population and the low-income group are two important criteria based on which EJ areas are being identified. These unique areal characteristics have been of particular interest to the traffic safety analysts in order to investigate the contributing factors of pedestrian crashes in these deprived areas. Pedestrian and bicycle crashes were estimated as a function of variables related to roadway characteristics, and various demographic and socio-economic factors. It was found that significant differences are present between the predictor sets for pedestrian and bicycle crashes. In all cases the models with spatial correlation performed better than the models that did not account for spatial correlation among TAZs. This finding implied that spatial correlation should be considered while modeling pedestrian and bicycle crashes at the aggregate or macro-level. Also, the significance of spatial autocorrelation was later found in the total and severe crash analyses and accounted for in their respective modeling techniques.Since the study found affirmative evidence about the inclusion of spatial autocorrelation in the safety performance functions, this research considered identifying appropriate spatial entity based on which TSP framework would be developed. A wide array of spatial units has been explored in macro-level crash modeling in previous safety research. With the advancement of GIS, safety analysts are able to analyze crashes for various geographical units. However, a clear guideline on which geographic entity should a modeler choose is not present so far. This preference of spatial unit can vary with the dependent variable of the model. Or, for a specific dependent variable, models may be invariant to multiple spatial units by producing a similar goodness-of-fits. This problem is closely related to the Modifiable Areal Unit Problem which is a common issue in spatial data analysis. The study investigated three different crash (total, severe, and pedestrian) models developed for TAZs, block groups (BGs) and census tracts (CTs) using various roadway characteristics and census variables (e.g., land use, socio-economic, etc.); and compared them based on multiple goodness-of-fit measures.Based on MAD and MSPE it was evident that the total, severe and pedestrian crash models for TAZs and BGs had similar fits, and better than the ones developed for CTs. This indicated that the total, severe and pedestrian crash models are being affected by the size of the spatial units rather than their zoning configurations. So far, TAZs have been the base spatial units of analyses for developing travel demand models. Metropolitan planning organizations widely use TAZs in developing their long range transportation plans (LRTPs). Therefore, considering the practical application it was concluded that as a geographical unit, TAZs had a relative ascendancy over block group and census tract.Once TAZs were selected as the base spatial unit of the TSP framework, careful inspections on the TAZ delineations were performed. Traffic analysis zones are often delineated by the existing street network. This may result in considerable number of crashes on or near zonal boundaries. While the traditional macro-level crash modeling approach assigns zonal attributes to all crashes that occur within the zonal boundary, this research acknowledged the inaccuracy resulting from relating crashes on or near the boundary of the zone to merely the attributes of that zone. A novel approach was proposed to account for the spatial influence of the neighboring zones on crashes which specifically occur on or near the zonal boundaries. Predictive model for pedestrian crashes per zone were developed using a hierarchical Bayesian framework and utilized separate predictor sets for boundary and interior (non-boundary) crashes. It was found that these models (that account for boundary and interior crashes separately) had better goodness-of-fit measures compared to the models which had no specific consideration for crashes located at/near the zone boundaries. Additionally, the models were able to capture some unique predictors associated explicitly with interior and boundary-related crashes. For example, the variables- 'total roadway length with 35mph posted speed limit' and 'long term parking cost' were statistically not significantly different from zero in the interior crash model but they were significantly different from zero at the 95% level in the boundary crash model.Although an adjacent traffic analysis zones (a single layer) were defined for pedestrian crashes and boundary pedestrian crashes were modeled based on the characteristic factors of these adjacent zones, this was not considered reasonable for bicycle-related crashes as the average roaming area of bicyclists are usually greater than that of pedestrians. For smaller TAZs sometimes it is possible for a bicyclist to cross the entire TAZ. To account for this greater area of coverage, boundary bicycle crashes were modeled based on two layers of adjacent zones. As observed from the goodness-of-fit measures, performances of model considering single layer variables and model considering two layer variables were superior from the models that did not consider layering at all; but these models were comparable. Motor vehicle crashes (total and severe crashes) were classified as 'on-system' and 'off-system' crashes and two sub-models were fitted in order to calibrate the safety performance function for these crashes. On-system and off-system roads refer to two different roadway hierarchies. On-system or state maintained roads typically possess higher speed limit and carries traffic from distant TAZs. Off-system roads are, however, mostly local roads with relatively low speed limits. Due to these distinct characteristics, on-system crashes were modeled with only population and total employment variables of a zone in addition to the roadway and traffic variables; and all other zonal variables were disregarded. For off-system crashes, on contrary, all zonal variables was considered. It was evident by comparing this on- and off-system sub-model-framework to the other candidate models that it provided superior goodness-of-fit for both total and severe crashes.Based on the safety performance functions developed for pedestrian, bicycle, total and severe crashes, the study proposed a novel and complete framework for assessing safety (of these crash types) simultaneously in parallel with the four-step transportation planning process with no need of any additional data requirements from the practitioners' side.
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Date Issued: 2012
Identifier: CFE0004191, ucf:49009
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0004191

Title: Financial evaluation of milege based user fees for Florida's transportation funding.
Creator: Moradi, Massoud, Al-Deek, Haitham, Radwan, Ahmed, Abdel-Aty, Mohamed, Uddin, Nizam, University of Central Florida
Abstract / Description: ABSTRACTMotor fuel taxes have been collected as a principal source of highway funding for close to a century. They account for approximately two thirds of all the highway user fees and about half of all highway expenditures. Federal fuel taxes have not kept pace with the inflation in general and increasing traffic demand and resulting construction, maintenance and operation costs of the transportation assets in particular.Lack of political will, combined with rising anti-tax sentiment among...
Show moreABSTRACTMotor fuel taxes have been collected as a principal source of highway funding for close to a century. They account for approximately two thirds of all the highway user fees and about half of all highway expenditures. Federal fuel taxes have not kept pace with the inflation in general and increasing traffic demand and resulting construction, maintenance and operation costs of the transportation assets in particular.Lack of political will, combined with rising anti-tax sentiment among the populace, has kept the federal tax level not only well below its initial intents, but also at a unsustainable level in future.Mileage based user fees are possibly an alternative to the fuel taxes, which have been the main mechanism for funding the transportation system.Mileage based user fees have been successfully utilized in many parts of the world with glowing results. Germany's (")TollCollect("), a quasi government enterprise has utilized GPS technology in collecting the users' fee from the truck operators. The system has been a financial engine providing much needed funding for many major transportation projects. Oregon Department of Transportation, in a federally co-funded pilot project, examined the practicality of the mileage based user fee collection at the fuel pumps. According to the Oregon study, there are not any major technical difficulties in mileage based user fee collection at the pump. Study participants (general motorist) did not express any objection to the mileage based user fee collection.This dissertation evaluates revenue impacts of several pricing policies including: Current per gallon fuel taxes, conversion to a mileage based user fee, time of day user fee application, area type user fee and congestion priced user fees. State of Florida's years 2015-2035 fuel revenue forecast is used as a case study. A model is constructed to estimate annual vehicle miles travelled for the analyses period. Fuel efficiencies, current per gallon fuel taxes and their corresponding mileage-based user fee equivalents are the input to a financial model developed for comparisons. Results demonstrate that decrease in fuel revenues due to vehicles fuel efficiency improvements can be offset by replacing current per gallon fuel taxes with a mileage-based user fee. Pricing the user fee according to area type, roadway classification, time of day and congestion level can not only generate more revenues but also assist in demand management.
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Date Issued: 2012
Identifier: CFE0004416, ucf:49378
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0004416

Title: Econometric Modeling Analysis of Public Transit Ridership: Application for Orlando Region.
Creator: Rahman, Moshiur, Eluru, Naveen, Abdel-Aty, Mohamed, Yasmin, Shamsunnahar, Uddin, Nizam, University of Central Florida
Abstract / Description: Policy makers are considering several alternatives to counter the negative externalities of personal vehicle dependence. Towards this end, public transit investments are critical in growing urban regions such as Orlando, Florida. Transit system managers and planners mostly rely on statistical models to identify the factors that affect ridership as well as quantifying the magnitude of the impact on the society. These models provide vital feedback to agencies on the benefits of public transit...
Show morePolicy makers are considering several alternatives to counter the negative externalities of personal vehicle dependence. Towards this end, public transit investments are critical in growing urban regions such as Orlando, Florida. Transit system managers and planners mostly rely on statistical models to identify the factors that affect ridership as well as quantifying the magnitude of the impact on the society. These models provide vital feedback to agencies on the benefits of public transit investments which in turn act as lessons to improve the investment process. We contribute to public transit literature by addressing several methodological challenges for transit ridership modeling. Frist, we examine the impact of new transit investments (such as an addition of commuter rail to an urban region) on existing transit infrastructure (such as the traditional bus service already present in the urban region). The process of evaluating the impact of new investments on existing public transit requires a comprehensive analysis of the before and after measures of public transit usage in the region. Second, we accommodate for the presence of common unobserved factors associated with spatial factors by developing a spatial panel model using stop level public transit boarding and alighting data. Third, we contribute to literature on transit ridership by considering daily boarding and alighting data from a recently launched commuter rail system (SunRail). The model system developed will allow us to predict ridership for existing stations in the future as well as potential ridership for future expansion sites. Fourth, we accommodate for potential endogeneity between bus headway and ridership by proposing a simultaneous model system of headway and ridership. Finally, a cost benefit analysis exercise is conducted for examining the impact of Sunrail on the region.
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Date Issued: 2018
Identifier: CFE0007583, ucf:52577
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0007583

Title: Helping Mothers Defend their Decision to Breastfeed.
Creator: Natoli, Kandis, Aroian, Karen, Covelli, Maureen, Quelly, Susan, Uddin, Nizam, Miller, Ann, University of Central Florida
Abstract / Description: The United States has established breastfeeding as an important health indicator within the Healthy People agenda. Healthy People target goals for breastfeeding initiation, duration, and exclusivity remain unmet. The US Surgeon General's Office reports that lack of knowledge and widespread misinformation about breastfeeding are barriers to meeting Healthy People goals. Breastfeeding mothers are vulnerable to messages that cast doubt on their ability to breastfeed. Very little research has...
Show moreThe United States has established breastfeeding as an important health indicator within the Healthy People agenda. Healthy People target goals for breastfeeding initiation, duration, and exclusivity remain unmet. The US Surgeon General's Office reports that lack of knowledge and widespread misinformation about breastfeeding are barriers to meeting Healthy People goals. Breastfeeding mothers are vulnerable to messages that cast doubt on their ability to breastfeed. Very little research has examined specific approaches to help people resist negative messages about health beliefs and behaviors. The objective of this quasi-experimental study was to test an intervention designed to help mothers defend their breastfeeding decisions and resist influences that attempted to persuade them to give formula to their babies. Women attending prenatal breastfeeding classes were recruited and assigned to comparison and intervention groups. The intervention was a board game based on McGuire's inoculation theory of resistance to influence. Controlling for intention to breastfed, intervention and comparison groups were examined for differences in maternal self-efficacy to resist persuasion to give formula and breastfeeding rates for initiation, duration, and exclusivity. Data analyses consisted of analysis of covariance and logistic regression. There was no significant difference between comparison and intervention groups, both groups had high self-efficacy to resist giving formula to their babies; nor were there significant differences regarding breastfeeding initiation, duration and exclusivity. The lack of significant differences may have been influenced by ceiling effects in all of the breastfeeding variables, possibly due to the high socioeconomic level of the sample. The intervention may have worked better in women who were more prone to dissuasive influence, such as those with lower education.
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Date Issued: 2015
Identifier: CFE0005981, ucf:50764
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0005981

Title: Dynamic Modeling Approach to Quantify Change Orders Impact on Labor Productivity.
Creator: Al-Kofahi, Zain, Oloufa, Amr, Tatari, Omer, Uddin, Nizam, Xanthopoulos, Petros, University of Central Florida
Abstract / Description: In construction projects, change orders are commonly faced. These change orders, which are issued by the owner, may cause interruption to the contractor's work, resulting in damages such as loss of labor productivity, delay damages, and cost overruns which may lead to claims. The relationship between change orders and loss of labor productivity is not well understood because of the difficulty in linking the cause of the productivity loss to the change order. So, to receive compensation, the...
Show moreIn construction projects, change orders are commonly faced. These change orders, which are issued by the owner, may cause interruption to the contractor's work, resulting in damages such as loss of labor productivity, delay damages, and cost overruns which may lead to claims. The relationship between change orders and loss of labor productivity is not well understood because of the difficulty in linking the cause of the productivity loss to the change order. So, to receive compensation, the contractor needs to prove with a credible calculation that the productivity loss was a result of the change order issued by the owner. Compared to all available productivity loss quantification methods, the (")Measured Mile(") approach is considered the most acceptable and popular approach in litigation. In this study, loss of labor productivity due to change orders is studied using a system dynamics method. A system dynamics model is developed using Vensim Software, validated, and utilized to quantitatively measure the impact of the change in the project scope on labor productivity. Different road construction projects were analyzed using both methods: measured mile analysis and system dynamics model; then, the results from those two approaches were compared
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Date Issued: 2016
Identifier: CFE0006430, ucf:51448
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0006430

Title: Evaluating Wrong-Way Driving for Florida Interstates and Toll Road Facilities: A Risk-Based Investigation, and Countermeasure Development.
Creator: Rogers, John, Al-Deek, Haitham, Tatari, Omer, Eluru, Naveen, Uddin, Nizam, University of Central Florida
Abstract / Description: The focus of this dissertation was to examine wrong-way driving (WWD) events on Florida toll roads and Interstates. The universe of WWD data contains many sources of WWD events or incidents. Most of the previous research focused only on WWD crashes without considering other data such as WWD citations and 911 calls related to WWD incidents. While WWD citations and 911 calls data is abundant, this data has been largely overlooked in other studies. This dissertation provides a novel and holistic...
Show moreThe focus of this dissertation was to examine wrong-way driving (WWD) events on Florida toll roads and Interstates. The universe of WWD data contains many sources of WWD events or incidents. Most of the previous research focused only on WWD crashes without considering other data such as WWD citations and 911 calls related to WWD incidents. While WWD citations and 911 calls data is abundant, this data has been largely overlooked in other studies. This dissertation provides a novel and holistic approach for evaluating WWD risk, which considers other risk factors such as WWD citations and 911 calls in addition to WWD crashes.WWD crashes are rare because they are less than 3% of all crashes, which makes them difficult to predict and analyze. WWD is very dangerous especially on high-speed limited access facilities. A right way driver on the mainline has very little time to take an action and avoid a wrong-way vehicle since the combined approach speed rates of both vehicles is very high. There is an average of 300 to 400 fatalities every year in the United States due to WWD crashes. There were 386 fatalities in Florida due to WWD crashes from 2007(-)2011; this ranked Florida third in terms of total WWD fatalities.There are many causes for WWD. The majority of WWD crashes occur during late night hours, and these crashes can be attributed to intoxicated drivers, confused/elderly drivers, and suicidal drivers. However, these are not all of the causes of WWD. In order to understand WWD, it is important to look beyond crash events. This research focused on two major toll road networks in Florida, which were the Central Florida Expressway (CFX) and the Florida Turnpike Enterprise (FTE). Overall, WWD crashes on the FTE system accounted for around 0.45% of all crashes, but accounted for 1.5% of fatal crashes. WWD on FTE shows that 15.2% of these crashes are usually fatal compared to only 2% of all WWD rural freeway crashes are fatal and only 0.7% of urban freeway crashes are fatal. In the citation data, not all wrong way drivers were issued citations. 15% of the WWD citations in the FTE dataset resulted in a crash. While analyzing the citation events, it has been found that they commonly do not result in crashes. However, the mere fact that a driver gets a wrong way driving citation, because he or she failed to correct his driving action before a police officer arrives at the scene, is by itself a risky behavior. The WWD Traffic Management Center (TMC) SunGuide data was explored in depth for the FTE system. 55% of the SunGuide events were never found, 11% were pulled over by Law Enforcement Officers (LEO), and 8% of the events resulted in crashes. 19% of the events were false calls. In 3% of the events, drivers corrected their WW action without an incident or crash. Understanding the relationships between non-crash WWD events (WWD citations and 911 calls) and WWD crash events is essential. The interaction between crash events and non-crash events was explored using six different models developed in this dissertation. Weighted crash risk values, which use all three types of WWD events (crashes, citations, and 911 calls), were created using the developed models from this research and were applied to rank locations in priority for enhanced WWD countermeasures. Model 1, a generalized linear model referred to as GLM 1, was developed from Florida statewide WWD data on limited access routes. GLM 1 was built using a Poisson's function. Non-crash events (citations and 911 events) were modeled to predict WWD crash events while leveraging the statewide count data that was broken down by hour of the day. The results of GLM 1 showed that Broward and Miami-Dade Counties are some of the hottest counties in Florida for WWD, and SR 821 located in these two counties is one of the hottest routes for WWD in Florida. SR 821 ranked highest in terms of WWD crash risk using a statewide developed model in this dissertation. Model 2, which was another generalized linear model (referred to as GLM 2), used an additional time variable to square the hour difference from noon. The form of GLM 2 was similar to GLM 1, but the results of GLM 1 were a little stronger than GLM 2. Another model using Artificial Neural Network (ANN) was developed and compared to GLM 2. It was found that ANN provided a stronger fit of WWD crash predictions compared to GLM 1 and GLM 2. However, when the ANN was used with other non-crash events to produce a crash prediction values outside of its original data set, the ANN model was not very useful for this application because of ANN's nature to overfit its original data set.Model 3, noted as GLM 3, used yearly non-crash data in South Florida to predict an entire route WWD crashes annually. Model 4, also noted as GLM 4, was one of the most useful models created from this body of work and used the same South Florida network as GLM 3. Using non-crash events and route characteristics such as geometric design configurations and traffic volumes at interchanges within the segment, GLM 4 predicts WWD crashes within 7- interchange route segments over a 4 year time period. GLM 4 used a method to aggregate the 7-interchange route segments, which leveraged more data points by overlapping segments to provide a larger data set of WWD crashes. The predicted WWD crashes from GLM 4 were added to the actual WWD crashes to produce a 7-interchange crash risk value. Using this WWD risk assessment method allows for the inclusion of more than just WWD crashes when evaluating and prioritizing sites for implementation of WWD countermeasures. In addition, using segments/corridors to target countermeasures is a smart approach for combating the WWD problem because in many instances, it is difficult to know where the WWD event first started or got initiated, and some of the WW drivers can travel considerable distances before they are either apprehended by law enforcement or end up crashing with the oncoming traffic. Similar to GLM 4, GLM 5 was another route segment model developed using WWD data collected for the Central Florida region's limited access network. The developed GLM 5 used 5-interchange segments to predict crash risk. Both GLM 4 and GLM 5 models were microscopic in the sense that they prioritize candidate interchanges for implementation of WWD countermeasures.In order to go beyond the minimal standards for combating WW, Florida toll road agencies are testing enhanced/flashing (")Wrong Way(") signs at exit ramps. These flashing devices add more emphasis to the existing (")Wrong Way(") signs (and or other traffic control devices) at the exit ramps. The CFX's application of the Rectangular Rapid Flashing Beacon (RRFB) for (")Wrong Way(") signs is an entirely new concept that was applied in Central Florida for the first time. The FTE's application of the MUTCD approved Blinker Sign for (")Wrong Way(") has been used in other states such as Texas. These countermeasures were examined and briefly studied during their test pilot phases. Partial results are documented in this dissertation but continuous observations and data collection at the pilot test sites and potential expansions of these sites in South and Central Florida (and other parts of the state) are needed for complete and comprehensive evaluation of the effectiveness of these new technologies.The FTE SunGuide TMC WWD event durations were collected for the nearest known interchange from the SunGuide reports. This information was compiled for the entire FTE system of interchanges. These SunGuide WWD event durations show the time spent by the FTE operators while actively combating and responding to various WWD events (never found events, pulled over events, and crashes). A method using the actual time spent responding to WWD, and the estimated duration of response (prior to the introduction of SunGuide) to crashes, citations, and 911 calls was developed to rank the interchanges in order of highest durations to lowest. The method developed in this dissertation showed the top percentiles in terms of durations (in minutes), and was used to cross check with the risk ranking of the WWD risk segment models GLM 4 and GLM 5. However, the SunGuide durations method is unique and robust because it weighs in individual interchanges using one common metric of WWD; i.e., total durations of response to the event at each interchange in the FTE system.Engineered countermeasures are important but these countermeasures are only effective if wrong-way drivers understand what they indicate. The Florida driver WWD survey implemented for this research showed that more than half of the respondents did not understand the meanings of the DO NOT ENTER symbol (only 44% of respondents were correct), and only 49% of respondents understood what wrong-way pavement arrows correctly mean. Over 70% of the 900 random respondents surveyed indicate their preference to RRFBs over the BlinkLink Signs. This is important to consider when expanding the implementation of countermeasures to other sites on the FTE system. The implementation of enhanced Intelligent Transportation System (ITS) countermeasure devices shows that Florida toll road agencies are working effectively towards reducing and correcting WWD events on their toll roads' networks. Reducing the risk of WWD crashes and non-crash events in general contributes significantly to the important goal of saving lives and money.
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Date Issued: 2016
Identifier: CFE0006544, ucf:51322
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0006544

Title: Techniques for automated parameter estimation in computational models of probabilistic systems.
Creator: Hussain, Faraz, Jha, Sumit, Leavens, Gary, Turgut, Damla, Uddin, Nizam, University of Central Florida
Abstract / Description: The main contribution of this dissertation is the design of two new algorithms for automatically synthesizing values of numerical parameters of computational models of complexstochastic systems such that the resultant model meets user-specified behavioral specifications.These algorithms are designed to operate on probabilistic systems (-) systems that, in general,behave differently under identical conditions. The algorithms work using an approach thatcombines formal verification and...
Show moreThe main contribution of this dissertation is the design of two new algorithms for automatically synthesizing values of numerical parameters of computational models of complexstochastic systems such that the resultant model meets user-specified behavioral specifications.These algorithms are designed to operate on probabilistic systems (-) systems that, in general,behave differently under identical conditions. The algorithms work using an approach thatcombines formal verification and mathematical optimization to explore a model's parameterspace.The problem of determining whether a model instantiated with a given set of parametervalues satisfies the desired specification is first defined using formal verification terminology,and then reformulated in terms of statistical hypothesis testing. Parameter space explorationinvolves determining the outcome of the hypothesis testing query for each parameter pointand is guided using simulated annealing. The first algorithm uses the sequential probabilityratio test (SPRT) to solve the hypothesis testing problems, whereas the second algorithmuses an approach based on Bayesian statistical model checking (BSMC).The SPRT-based parameter synthesis algorithm was used to validate that a given model ofglucose-insulin metabolism has the capability of representing diabetic behavior by synthesizingvalues of three parameters that ensure that the glucose-insulin subsystem spends at least 20minutes in a diabetic scenario. The BSMC-based algorithm was used to discover the valuesof parameters in a physiological model of the acute inflammatory response that guarantee aset of desired clinical outcomes.These two applications demonstrate how our algorithms use formal verification, statisticalhypothesis testing and mathematical optimization to automatically synthesize parameters ofcomplex probabilistic models in order to meet user-specified behavioral properties
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Date Issued: 2016
Identifier: CFE0006117, ucf:51200
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0006117

Title: Evaluating Moral Distress, Moral Distress Residue and Moral Courage in Oncology Nurses.
Creator: Melhado, Lolita, Chase, Susan, Conner, Norma, Loerzel, Victoria, Uddin, Nizam, Haley, William, University of Central Florida
Abstract / Description: Purpose: To examine relationships between moral distress, moral distress residue, and moral courage and to determine which nurse characteristics are predictive of moral distress and moral courage.Methods: The study used a mixed methods cross-sectional correlation design and qualitative content analysis to investigate oncology nurses' characteristics and relationships between moral distress, moral distress residue, and moral courage. A convenience sample of 187 oncology nurses working in...
Show morePurpose: To examine relationships between moral distress, moral distress residue, and moral courage and to determine which nurse characteristics are predictive of moral distress and moral courage.Methods: The study used a mixed methods cross-sectional correlation design and qualitative content analysis to investigate oncology nurses' characteristics and relationships between moral distress, moral distress residue, and moral courage. A convenience sample of 187 oncology nurses working in inpatient and outpatient settings was recruited through the national Oncology Nursing Society in the Southeastern United States. Hamric's 21-item Moral Distress Scale-Revised (MDS-R) and Sekerka et al. 15-item Professional Moral Courage Scale (PMCS) supplemented with written examples of moral courage were used for data collection. Descriptive statistics, independent-samples t test, Pearson correlation, ANOVA, and multiple regressions analyses were used to evaluate data.Findings: MDS-R scores were not predictive of PMCS scores. No statistically significant differences were found between nurses' characteristics (age, education level, certification, ELNEC training) and MDS-R. Though nurses with BSN had higher Moral Distress scores compared with other levels of education, none were predictors of MDS-R. ANOVA results indicate a marginal but not significant difference of the MDS-R score among the nurses with different basic ethics education (p = .067). Nurses working in adult inpatient settings had significantly higher MDS-R than those in outpatient settings. Nurses who had moral distress residue by virtue of leaving a previous job (26%) and those who considered leaving (28%) reported statistically significantly higher mean Moral Distress levels than those who had not considered leaving. Nurses (17%) currently considering leaving their jobs due to the way patient care was handled at their institutions had the highest Moral Distress mean scores and the lowest Professional Moral Courage scores. Work setting and having left a previous job were weak predictors of MDS-R, accounting for 11.6% of the moral distress score variance (p = .013) compared with 4.4% when work setting was a single predictor (p = .014). Total years' oncology experience was a weak predictor of PMCS, accounting for 2.5% or an inconsequential amount of the variance (p = .043). Moral courage was displayed in major areas of supporting the patient, risk taking, advocacy, enlarging the circle for decision-making, putting aside personal beliefs, respecting patient autonomy, empowering the patient, fighting for the patient in face of consequences in a complex system, sharing information, getting to the meaning, handling tricky situations, protecting the patient and truth-telling.Discussion/Implication: Despite experiencing levels of moral distress, oncology nurses demonstrate support and respect for patients' decision-making and autonomy. Ethics education derived from clinical practice can provide an opportunity for open discussion for nurses to create and maintain morally acceptable work environments that enable them to be morally courageous. This research underscores the presence of moral distress and moral distress residue among oncology nurses and the importance of finding ways to lessen moral distress and strengthen moral courage in nurses.
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Date Issued: 2016
Identifier: CFE0006142, ucf:51175
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0006142

Healthcare (2)	+ -
Negative Binomial (2)	+ -
Wrong-Way Driving (2)	+ -
algorithms (2)	+ -
ANOVA (1)	+ -

Active Traffic Management (1)	+ -
Advanced Traveler Information Systems (1)	+ -
Agreement Measure (1)	+ -
Attendance (1)	+ -
Autism Spectrum Disorder (1)	+ -
BIM uses. (1)	+ -
BY:HAZHAR TALAAT ABUBAKEER BLBAS FROM KURDISTAN-IRAQ (1)	+ -
Before and After Study with a Comparison group (1)	+ -
Building Information Modeling (1)	+ -
CURVES (1)	+ -
Capture Recapture (1)	+ -
Caregiver (1)	+ -
Change Orders (1)	+ -
Civil Engineering (1)	+ -
Collinearity (1)	+ -
Commodity Flow Survey Data (1)	+ -
Coordinate Descent (1)	+ -
Coping (1)	+ -
Copula (1)	+ -
Countermeasure (1)	+ -
Data Collection (1)	+ -
Data Mining (1)	+ -
Demand forecast (1)	+ -
Demographic Analysis (1)	+ -
Destination Choice (1)	+ -

Uddin, Nizam (27)	+ -
University of Central Florida (27)	+ -
Abdel-Aty, Mohamed (9)	+ -
Al-Deek, Haitham (8)	+ -
Eluru, Naveen (5)	+ -

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