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Pages
- Title
- Social Media Usage by Municipal Elected Officials for Open Government Community Engagement.
- Creator
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Stoeckel, Sarah, Bryer, Thomas, Mitchell, David, Hu, Qian, Brown, Tim, University of Central Florida
- Abstract / Description
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As public administration has evolved with the technological advances in today's society, it can be challenging to ensure the demands of the public are being met in terms of efficiency, effectiveness, and engagement. Nonetheless, a focus on community remains at the forefront of public administration. When looking at technology and the community, the tool known as social media emerges. Social media has allowed people to interact in new ways and therefore, has allowed the government to interact...
Show moreAs public administration has evolved with the technological advances in today's society, it can be challenging to ensure the demands of the public are being met in terms of efficiency, effectiveness, and engagement. Nonetheless, a focus on community remains at the forefront of public administration. When looking at technology and the community, the tool known as social media emerges. Social media has allowed people to interact in new ways and therefore, has allowed the government to interact with citizens in ways they have not been able to in the past. In addition to attempting to modernize public administration, there has been an increased focus on building citizen trust through providing a more open government structure. The Open Government Directive issued by President Barack Obama focused on three tenets, which included transparency, participation, and collaboration. One of the ways government entities within the United States are strengthening these areas is through the implementation of various social media sites as a means to stay connected with citizens. With an increase of users utilizing social media tools for both information and connection, many government departments and agencies have incorporated social media use into their workplace as a function for their department. However, it is elected officials that are the ones who represent the citizens from their governmental role and thus, can aid in bridging the gap between citizens and government. Yet, there is little research on how elected officials, specifically in municipalities, are utilizing social media to connect with their constituents. This study discusses social media use by municipal elected officials and how it relates to open government community engagement. Open government community engagement is defined in terms of the three tenets of the Open Government Directive: transparency, participation, and collaboration encompassing the rungs of Arnstein's ladder of citizen participation. For this qualitative study, fifty-seven Florida municipal elected officials were interviewed regarding their social media use or lack thereof in terms of engagement with citizens. The interviews are followed-up with content analysis of social media sites. An ethnographic approach is utilized to uncover and develop common themes related to open government community engagement. The findings suggest while some municipal elected officials are utilizing social media well in terms of open government community engagement, there is a lack of clear understanding of social media use within the context of the Sunshine Law, as well as other barriers prohibiting utilizing social media for more of the participation and collaboration components. There are several reasons municipal elected officials opt to avoid social media altogether, while additional concepts related to open government limited engagement and closed government community engagement are explored. The concept of avoidance was addressed, especially as it pertained to the practical implications for both city administrators and elected officials.
Show less - Date Issued
- 2018
- Identifier
- CFE0007377, ucf:52083
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0007377
- Title
- THREE ESSAYS ON DIFFERENTIAL GAMES AND RESOURCE ECONOMICS.
- Creator
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Ling, Chen, Caputo, Michael, University of Central Florida
- Abstract / Description
-
This dissertation consists of three chapters on the topic of differential games and resource economics. The first chapter extends the envelope theorem to the class of discounted infinite horizon differential games that posses locally differentiable Nash equilibria. The theorems cover both the open-loop and feedback information structures, and are applied to a simple analytically solvable linear-quadratic game. The results show that the conventional interpretation of the costate variable as...
Show moreThis dissertation consists of three chapters on the topic of differential games and resource economics. The first chapter extends the envelope theorem to the class of discounted infinite horizon differential games that posses locally differentiable Nash equilibria. The theorems cover both the open-loop and feedback information structures, and are applied to a simple analytically solvable linear-quadratic game. The results show that the conventional interpretation of the costate variable as the shadow value of the state variable along the equilibrium path is only valid for feedback Nash equilibria, but not for open-loop Nash equilibria. The specific linear-quadratic structure provides some extra insights on the theorem. For example, the costate variable is shown to uniformly overestimate the shadow value of the state variable in the open-loop case, but the growth rate of the costate variable are the same as the shadow value under open-loop and feedback information structures. Chapter two investigates the qualitative properties of symmetric open-loop Nash equilibria for a ubiquitous class of discounted infinite horizon differential games. The results show that the specific functional forms and the value of parameters used in the game are crucial in determining the local asymptotic stability of steady state, the steady state comparative statics, and the local comparative dynamics. Several sufficient conditions are provided to identify a local saddle point type of steady state. An important steady state policy implication from the model is that functional forms and parameter values are not only quantitatively important to differentiate policy tools, but they are also qualitatively important. Chapter three shifts the interests to the lottery mechanism for rationing public resources. It characterizes the optimal pricing strategies of lotteries for a welfare-maximization agency. The optimal prices are shown to be positive for a wide range of individual private value distributions, suggesting that the sub-optimal pricing may result in a significant efficiency loss and that the earlier studies under zero-pricing may need to be re-examined. In addition, I identify the revenue and welfare equivalency propositions across lottery institutions. Finally, the numerical simulations strongly support the findings.
Show less - Date Issued
- 2010
- Identifier
- CFE0003195, ucf:48752
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0003195
- Title
- Quality Diversity: Harnessing Evolution to Generate a Diversity of High-Performing Solutions.
- Creator
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Pugh, Justin, Stanley, Kenneth, Wu, Annie, Sukthankar, Gita, Garibay, Ivan, University of Central Florida
- Abstract / Description
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Evolution in nature has designed countless solutions to innumerable interconnected problems, giving birth to the impressive array of complex modern life observed today. Inspired by this success, the practice of evolutionary computation (EC) abstracts evolution artificially as a search operator to find solutions to problems of interest primarily through the adaptive mechanism of survival of the fittest, where stronger candidates are pursued at the expense of weaker ones until a solution of...
Show moreEvolution in nature has designed countless solutions to innumerable interconnected problems, giving birth to the impressive array of complex modern life observed today. Inspired by this success, the practice of evolutionary computation (EC) abstracts evolution artificially as a search operator to find solutions to problems of interest primarily through the adaptive mechanism of survival of the fittest, where stronger candidates are pursued at the expense of weaker ones until a solution of satisfying quality emerges. At the same time, research in open-ended evolution (OEE) draws different lessons from nature, seeking to identify and recreate processes that lead to the type of perpetual innovation and indefinitely increasing complexity observed in natural evolution. New algorithms in EC such as MAP-Elites and Novelty Search with Local Competition harness the toolkit of evolution for a related purpose: finding as many types of good solutions as possible (rather than merely the single best solution). With the field in its infancy, no empirical studies previously existed comparing these so-called quality diversity (QD) algorithms. This dissertation (1) contains the first extensive and methodical effort to compare different approaches to QD (including both existing published approaches as well as some new methods presented for the first time here) and to understand how they operate to help inform better approaches in the future.It also (2) introduces a new technique for encoding neural networks for evolution with indirect encoding that contain multiple sensory or output modalities.Further, it (3) explores the idea that QD can act as an engine of open-ended discovery by introducing an expressive platform called Voxelbuild where QD algorithms continually evolve robots that stack blocks in new ways. A culminating experiment (4) is presented that investigates evolution in Voxelbuild over a very long timescale. This research thus stands to advance the OEE community's desire to create and understand open-ended systems while also laying the groundwork for QD to realize its potential within EC as a means to automatically generate an endless progression of new content in real-world applications.
Show less - Date Issued
- 2019
- Identifier
- CFE0007513, ucf:52638
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0007513
- Title
- Investigating the Effectiveness of Using Part-Task or Whole-Task Training Methods to Facilitate Mindful Abstraction in Uncertain Tasks.
- Creator
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Killilea, John, Martin, Glenn, Sims, Valerie, Hirumi, Atsusi, Schatz, Sarah, University of Central Florida
- Abstract / Description
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As the global landscape changes and powers rise and fall, the Contested, Degraded, and Operationally Limited (CDO) environment is likely to be the new normal going forward. Uncertainty variables, such as missing, false, or extra information characterize the CDO environment. A key focus of this dissertation is optimizing training for recognizing these uncertainty variables when training time is limited. This was investigated by either exposing participants to multiple uncertainty variables at...
Show moreAs the global landscape changes and powers rise and fall, the Contested, Degraded, and Operationally Limited (CDO) environment is likely to be the new normal going forward. Uncertainty variables, such as missing, false, or extra information characterize the CDO environment. A key focus of this dissertation is optimizing training for recognizing these uncertainty variables when training time is limited. This was investigated by either exposing participants to multiple uncertainty variables at a time with low doses of each (whole-task training), by exposing singular variables at a time with high doses (part-task training) or using no variables throughout training (control). A key motivator behind this research was Cognitive Load Theory, as mindful abstraction can only occur if there are cognitive resources to spare. Dependent variables, such as time to complete, number correct, task workload, and uncertainty variables identified, were collected.The results revealed that on the transfer task, the part-task condition recorded a significantly lower workload score than the whole-task (and control) condition, while the condition's workload scores were consistent across all training and transfer tasks. In contrast, the control and whole-task condition experienced significant increases in workload during the transfer task. Additionally, the part-task condition participants were able to significantly identify more uncertainty variables on the final task than the whole-task condition and control condition. The part-task condition found the transfer task to be the (")easiest(") in terms of workload, and as there is more opportunity for mindful abstraction if there are more cognitive resources available, it can be stated that based on these results, the part-task training schedule facilitated mindful abstraction more than the other two training schedules. As this was a limited, abstracted, and laboratory experiment, future work should apply the same methodology to applied tasks in a controlled environment to gauge further usefulness of this research.
Show less - Date Issued
- 2018
- Identifier
- CFE0007339, ucf:52119
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0007339
- Title
- INVESTIGATION OF THERMAL, ELASTIC AND LOAD-BIASED TRANSFORMATION STRAINS IN NITI SHAPE MEMORY ALLOYS.
- Creator
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Qiu, Shipeng, Vaidyanathan, Raj, University of Central Florida
- Abstract / Description
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Polycrystalline NiTi shape memory alloys have the ability to recover their original, pre-deformed shape in the presence of external loads when heated through a solid-solid phase transformation from a lower-symmetry B19' martensite phase to a higher-symmetry B2 austenite phase. The strain associated with a shape memory alloy in an actuator application typically has thermal, elastic and inelastic contributions. The objective of this work was to investigate the aforementioned strains by...
Show morePolycrystalline NiTi shape memory alloys have the ability to recover their original, pre-deformed shape in the presence of external loads when heated through a solid-solid phase transformation from a lower-symmetry B19' martensite phase to a higher-symmetry B2 austenite phase. The strain associated with a shape memory alloy in an actuator application typically has thermal, elastic and inelastic contributions. The objective of this work was to investigate the aforementioned strains by recourse to in situ neutron diffraction experiments during selected combinations of heating, cooling and/or mechanical loading. The primary studies were conducted on polycrystalline Ni49.9Ti50.1 specimens on the Spectrometer for MAterials Research at Temperature and Stress (SMARTS) at Los Alamos National Laboratory. Quantitative information on the phase-specific strain, texture and phase fraction evolution was obtained from the neutron data using Rietveld refinement and single-peak analyses, and compared with macroscopic data from extensometry. First, the lattice strain evolution during heating and cooling in an unloaded sample (i.e., free-recovery experiment) was studied. The lattice strain evolution remained linear with temperature and was not influenced by intergranular stresses, enabling the determination of a thermal expansion tensor that quantified the associated anisotropy due to the symmetry of B19' NiTi. The tensor thus determined was subsequently used to obtain an average coefficient of thermal expansion that was consistent with macroscopic dilatometric measurements and a 30,000 grain polycrystalline self-consistent model. The accommodative nature of B19' NiTi was found to account for macroscopic shape changes lagging (with temperature) the start and finish of the transformation. Second, the elastic response of B19' martensitic NiTi variants during monotonic loading was studied. Emphasis was placed on capturing and quantifying the strain anisotropy which arises from the symmetry of monoclinic martensite and internal stresses resulting from intergranular constraints between individual variants and load re-distribution among variants as the texture evolved during variant reorientation and detwinning. The methodology adopted took into account both tensile and compressive loading given the asymmetric response in the texture evolution. Plane specific elastic moduli were determined from neutron measurements and compared with those determined using a self-consistent polycrystalline deformation model and from recently reported elastic stiffness constants determined via ab initio calculations. The comparison among the three approaches further helped understand the influence of elastic anisotropy, intergranular constraint, and texture evolution on the deformation behavior of polycrystalline B19' NiTi. Connections were additionally made between the assessed elastic properties of martensitic NiTi single crystals (i.e., the single crystal stiffness tensor) and the overall macroscopic response in bulk polycrystalline form. Lastly, the role of upper-cycle temperature, i.e., the maximum temperature reached during thermal cycling, was investigated during load-biased thermal cycling of NiTi shape memory alloys at selected combinations of stress and temperature. Results showed that the upper-cycle temperature, under isobaric conditions, significantly affected the amount of transformation strain and thus the work output available for actuation. With the objective of investigating the underlying microstructural and micromechanical changes due to the influence of the upper-cycle temperature, the texture evolution was systematically analyzed. While the changes in transformation strain were closely related to the evolution in texture of the room temperature martensite, retained martensite in the austenite state could additionally affect the transformation strain. Additionally, multiple thermal cycles were performed under load-biased conditions in both NiTi and NiTiPd alloys, to further assess and understand the role of retained martensite. Dimensional and thermal stabilities of these alloys were correlated with the volume fraction and texture of retained martensite, and the internal strain evolution in these alloys. The role of symmetry, i.e., B19' monoclinic martensite vs. B19 orthorhombic martensite in these alloys was also assessed. This work not only established a methodology to study the thermal and elastic properties of the low symmetry B19' monoclinic martensite, but also provided valuable insight into quantitative micromechanical and microstructural changes responsible for the thermomechanical response of NiTi shape memory alloys. It has immediate implications for optimizing shape memory behavior in the alloys investigated, with extension to high temperature shape memory alloys with ternary and quaternary elemental additions, such as Pd, Pt and Hf. This work was supported by funding from NASAÂÂ's Fundamental Aeronautics Program, Supersonics Project (NNX08AB51A) and NSF (CAREER DMR-0239512). It benefited additionally from the use of the Lujan Neutron Scattering Center at Los Alamos National Laboratory, which is funded by the Office of Basic Energy Sciences (Department of Energy) and is operated by Los Alamos National Security LLC under DOE Contract DE-AC52-06NA25396.
Show less - Date Issued
- 2010
- Identifier
- CFE0003362, ucf:48440
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0003362
- Title
- Evaluation and Modeling of the Safety of Open Road Tolling System.
- Creator
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Abuzwidah, Muamer, Abdel-Aty, Mohamed, Radwan, Ahmed, Uddin, Nizam, University of Central Florida
- Abstract / Description
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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.
Show less - Date Issued
- 2011
- Identifier
- CFE0004466, ucf:49330
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0004466
- Title
- Nanocomposite Coating Mechanics via Piezospectroscopy.
- Creator
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Freihofer, Gregory, Raghavan, Seetha, Gou, Jihua, Bai, Yuanli, Schulzgen, Axel, University of Central Florida
- Abstract / Description
-
Coatings utilizing the piezospectroscopic (PS) effect of alpha alumina could enable on the fly stress sensing for structural health monitoring applications. While the PS effect has been historically utilized in several applications, here by distributing the photo-luminescent material in nanoparticle form within a matrix, a stress sensing coating is created. Parallel to developing PS coatings for stress sensing, the multi-scale mechanics associated with the observed PS response of...
Show moreCoatings utilizing the piezospectroscopic (PS) effect of alpha alumina could enable on the fly stress sensing for structural health monitoring applications. While the PS effect has been historically utilized in several applications, here by distributing the photo-luminescent material in nanoparticle form within a matrix, a stress sensing coating is created. Parallel to developing PS coatings for stress sensing, the multi-scale mechanics associated with the observed PS response of nanocomposites and their coatings has been applied to give material property measurements, providing an understanding of particle reinforced composite behavior.Understanding the nanoparticle-coating-substrate mechanics is essential to interpreting the spectral shifts for stress sensing of structures. In the past, methods to experimentally measure the mechanics of these embedded nano inclusions have been limited, and much of the design of these composites depend on computational modeling and bulk response from mechanical testing. The PS properties of Chromium doped alumina allow for embedded inclusion mechanics to be revisited with unique experimental setups that probe the particles state of stress under applied load to the composite. These experimental investigations of particle mechanics will be compared to the Eshelby theory and its derivative theories in addition to the nanocomposite coating mechanics. This work discovers that simple nanoparticle load transfer theories are adequate for predicting PS properties in an intermediate volume fraction range. With fundamentals of PS nanocomposites established, the approach was applied to selected experiments to prove its validity. In general it was observed that the elastic modulus values calculated from the PS response were similar to that observed from macroscale strain measurements such as a strain gage. When simple damage models were applied to monitor the elastic modulus, it was observed that the rate of decay for the elastic modulus was much higher for the PS measurements than for the strain gage.A novel experiment including high resolution PS maps with secondary strain maps from digital image correlation is reviewed on an open hole tension, composite coupon. The two complementary measurements allow for a unique PS response for every location around the hole with a spatial resolution of 400 microns. Progression of intermediate damage mechanisms was observed before digital image correlation indicated them. Using the PS nanocomposite model, elastic modulus values were calculated. Introducing an elastic degradation model with some plastic deformation allows for estimation of material properties during the progression of failure.This work is part of a continuing effort to understand the mechanics of a stress sensing PS coating. The mechanics were then applied to various experimental data that provided elastic property calculations with high resolution. The significance is in the experimental capture of stress transfer in particulate composites. These findings pave the way for the development of high resolution stress-sensing coatings.
Show less - Date Issued
- 2014
- Identifier
- CFE0005614, ucf:50223
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0005614
- Title
- INTERACTIVE TEXT-IMAGE CONCEPTUAL MODELS FOR LITERARY INTERPRETATION AND COMPOSITION IN THE DIGITAL AGE.
- Creator
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Weaver, Elizabeth, Saper, Craig, University of Central Florida
- Abstract / Description
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This dissertation focuses on text-image conceptual models for literary interpretation and composition in the digital age. The models investigate an interactive blend of textually-based linear-sequential approaches and visually-based spatial-simultaneous approaches. The models employ Gestalt-inspired figure-ground segregation models, along with other theoretical models, that demonstrate the dynamic capabilities of images as conceptual tools as well as alternate forms of text. The models...
Show moreThis dissertation focuses on text-image conceptual models for literary interpretation and composition in the digital age. The models investigate an interactive blend of textually-based linear-sequential approaches and visually-based spatial-simultaneous approaches. The models employ Gestalt-inspired figure-ground segregation models, along with other theoretical models, that demonstrate the dynamic capabilities of images as conceptual tools as well as alternate forms of text. The models encourage an interpretative style with active participants in open-ended, multi-sensory meaning-making processes. The models use the flexible tools of modern technology as approaches to meaning-making with art strategies used for research strategies as well as a means to appreciate reading and writing in the context of an increasingly visual environment.
Show less - Date Issued
- 2010
- Identifier
- CFE0003008, ucf:48335
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0003008
- Title
- Social Disorganization and Florida Public High School Academic Performance.
- Creator
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Kanaan, David, Wan, Thomas, Wolf, Ross, Stevenson, Robyne, Mitchell, David, University of Central Florida
- Abstract / Description
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Failing public high schools are a perpetual limitation to community sustainability. Conversely, economically disadvantaged communities more often produce schools with reduced academic performance. Unfortunately, comprehensive community-based remedies are generally outside the scope of a school district's control. Social disorganization theory attributes variations in crime and delinquency to a breakdown in communal structure and relationships. Applied in a similar manner, social...
Show moreFailing public high schools are a perpetual limitation to community sustainability. Conversely, economically disadvantaged communities more often produce schools with reduced academic performance. Unfortunately, comprehensive community-based remedies are generally outside the scope of a school district's control. Social disorganization theory attributes variations in crime and delinquency to a breakdown in communal structure and relationships. Applied in a similar manner, social disorganization has also been associated with lower student achievement.This research examined how social disorganization is associated with Florida public high school academic performance in a two phase analysis at the community and school district levels. In addition, the research tested a potential moderating effect of receiving the Five Star School Award, recognizing family and community involvement, and Florida public high school academic performance with social disorganization factors simultaneously considered. In the first phase, the study used a cross-sectional, non-experimental design analyzing secondary data by structural equation modeling (SEM) at the community-level. For the second phase, the study used a cross-sectional, non-experimental design analyzing aggregated secondary data in multiple linear regressions assessing statistically significant associations between social disorganization predictors and school academic performance variables at the school district-level. SEM analysis found a statistically significant and large negative association between the social disorganization factors residential mobility, single-parent households, socio-economic status and percentage of divorced or separated persons, and Florida public high school academic performance at the community-level. Also at the community-level, results showed that receiving the Five Star School award for satisfying family and community involvement criteria had a statistically significant but small positive association with Florida public high school performance when social disorganization factors were simultaneously considered. At the district or county level, multiple regression analyses found relevant negative associations between social disorganization predictors low median income and ethnic heterogeneity and school district average FCAT scores and Adequate Yearly Progress (AYP) percentages. The study results reinforce existing neighborhood deprivation and social disorganization literature and articulate the need for a community-based approach to improve high school academic performance. Finally, the research suggests prominent education policy reforms may exacerbate social disorganization in communities and proposes alternative policy implementations.
Show less - Date Issued
- 2016
- Identifier
- CFE0006335, ucf:51548
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0006335
- Title
- Textbook Cost-Lowering Initiatives: An Exploration of Community College Faculty Experiences.
- Creator
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Dunn, Susan, Cintron Delgado, Rosa, Owens, James, Boyd, Tammy, Mcardle, Michele, University of Central Florida
- Abstract / Description
-
Faculty have been identified as critical players in the implementation of textbook affordability efforts at community colleges. Furthermore, emerging lower-cost alternatives to traditional textbooks present a wide and growing range of options that may help further efforts. This study sought to examine more closely the role of faculty with respect to textbook cost-lowering initiatives. The researcher utilized in-depth interviews to gain a rich picture of the experiences, attitudes, beliefs,...
Show moreFaculty have been identified as critical players in the implementation of textbook affordability efforts at community colleges. Furthermore, emerging lower-cost alternatives to traditional textbooks present a wide and growing range of options that may help further efforts. This study sought to examine more closely the role of faculty with respect to textbook cost-lowering initiatives. The researcher utilized in-depth interviews to gain a rich picture of the experiences, attitudes, beliefs, and behaviors of nine full-time community college faculty as they confronted textbook affordability efforts and textbook alternatives. The interview data were analyzed using a thematic analysis process. Five major themes and three minor themes were identified. The five major themes were: (a) campus administrators support, but do not mandate, efforts; (b) frequent edition revisions frustrate faculty; (c) departmental approaches to textbook selection vary; (d) content, then affordability, drive selection choices; and (e) faculty have mixed feelings about textbook alternatives. The three minor themes were: (a) faculty efforts to save students money are thwarted by campus bookstores and financial aid policies; (b) English faculty benefit from public domain readings; and (c) more faculty participating in textbook selection means more difficulty deciding on a text. Implications and recommendations were offered for community college leaders, campus bookstores, publishers, and future researchers.
Show less - Date Issued
- 2014
- Identifier
- CFE0005159, ucf:50715
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0005159
- Title
- TRAFFIC SAFETY ASSESSMENT OF DIFFERENT TOLL COLLECTION SYSTEMS ON EXPRESSWAYS USING MULTIPLE ANALYTICAL TECHNIQUES.
- Creator
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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.
Show less - Date Issued
- 2014
- Identifier
- CFE0005751, ucf:50100
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0005751
