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Development of Decision Support System for Active Traffic Management Systems Considering Travel Time Reliability
Title
Development of Decision Support System for Active Traffic Management Systems Considering Travel Time Reliability.
Creator
Chung, Whoibin, Abdel-Aty, Mohamed, Eluru, Naveen, Hasan, Samiul, Cai, Qing, Huang, Hsin-Hsiung, University of Central Florida
Abstract / Description
As traffic problems on roadways have been increasing, active traffic management systems (ATM) using proactive traffic management concept have been deployed on freeways and arterials. The ATM aims to integrate and automate various traffic control strategies such as variable speed limits, queue warning, and ramp metering through a decision support system (DSS). Over the past decade, there have been many efforts to integrate freeways and arterials for the efficient operation of roadway networks....
Show moreAs traffic problems on roadways have been increasing, active traffic management systems (ATM) using proactive traffic management concept have been deployed on freeways and arterials. The ATM aims to integrate and automate various traffic control strategies such as variable speed limits, queue warning, and ramp metering through a decision support system (DSS). Over the past decade, there have been many efforts to integrate freeways and arterials for the efficient operation of roadway networks. It has been required that these systems should prove their effectiveness in terms of travel time reliability. Therefore, this study aims to develop a new concept of a decision support system integrating variable speed limits, queue warning, and ramp metering on the basis of travel time reliability of freeways and arterials.Regarding the data preparation, in addition to collecting multiple data sources such as traffic data, crash data and so on, the types of traffic data sources that can be applied for the analysis of travel time reliability were investigated. Although there are many kinds of real-time traffic data from third-party traffic data providers, it was confirmed that these data cannot represent true travel time reliability through the comparative analysis of measures of travel time reliability. Related to weather data, it was proven that nationwide land-based weather stations could be applicable.Since travel time reliability can be measured by using long-term periods for more than six months, it is necessary to develop models to estimate travel time reliability through real-time traffic data and event-related data. Among various matrix to measure travel time reliability, the standard deviation of travel time rate [minute/mile] representing travel time variability was chosen because it can represent travel time variability of both link and network level. Several models were developed to estimate the standard deviation of travel time rate through average travel time rate, the number of lanes, speed limits, and the amount of rainfall.Finally, a DSS using a model predictive control method to integrate multiple traffic control measures was developed and evaluated. As a representative model predictive control, METANET model was chosen, which can include variable speed limit, queue warning, and ramp metering, separately or combined. The developed DSS identified a proper response plan by comparing travel time reliability among multiple combinations of current and new response values of strategies. In the end, it was found that the DSS provided the reduction of travel time and improvement of its reliability for travelers through the recommended response plans.
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Date Issued
2019
Identifier
CFE0007615, ucf:52542
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFE0007615
A DIALECTICAL METHODOLOGY FOR DECISION SUPPORT SYSTEMS DESIGN
Title
A DIALECTICAL METHODOLOGY FOR DECISION SUPPORT SYSTEMS DESIGN.
Creator
Elgarah, Wafa, Courtney, James, University of Central Florida
Abstract / Description
As organizations continue to grow in size, reaching global proportions, they have ever increasing impacts on their environments. Some believe that a much broader array of concerns should be brought into organizational decision-making processes, including greater consideration of social, political, ethical and aesthetic factors (Mitroff and Linstone, 1993; Courtney, 2001). Decision environments such as these are decidedly "wicked" (Rittel and Webber, 1973). Designing decision support systems...
Show moreAs organizations continue to grow in size, reaching global proportions, they have ever increasing impacts on their environments. Some believe that a much broader array of concerns should be brought into organizational decision-making processes, including greater consideration of social, political, ethical and aesthetic factors (Mitroff and Linstone, 1993; Courtney, 2001). Decision environments such as these are decidedly "wicked" (Rittel and Webber, 1973). Designing decision support systems in such environments where there is a high level of interconnectedness, issues are overlapping and a multiplicity of stakeholders is involved, is a very complex task. In this dissertation a methodology for the development of a DSS for wicked situations is proposed using the design theory building process suggested by Walls et al. (1992). This proposed theory is based on dialectic theory and the multiple perspective approach suggested by Linstone and Mitroff (1993). The design process consists of identifying relevant stakeholders, their respective worldviews, and conflicts in these worldviews. A design (thesis) and "counter design" (antithesis) are created, and a prototype systems based on these designs are developed. These prototypes are then presented to the different stakeholder groups who engage in a dialogue which leads to the development of a synthesized design. The process is repeated until all conflicts are resolved or resources are exhausted, and a final system is produced. Using action research and system development research methodologies, the proposed design theory was applied to zoning decision process in Orange County, Florida. The results of this study led to the following: 1. It is feasible to implement the MPDP methodology proposed in this dissertation. 2. The MPDP methodology resulted in a synthesized design that accommodates the different views of the stakeholders. 3. The MPDP methodology is suitable for contentious situations and may not be feasible for structured decisions. 4. Most of the subjects did achieve a more understanding of the decision process. These results suggest that the MPDP design theory can be effective in developing decision support systems in contentious situations.
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Date Issued
2005
Identifier
CFE0000883, ucf:46637
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFE0000883
A DECISION SUPPORT SYSTEM METHODOLOGY FOR THE SELECTION OF RAPID PROTOTYPING TECHNOLOGIES FOR INVESTMENT-CAST GAS TURBINE PARTS
Title
A DECISION SUPPORT SYSTEM METHODOLOGY FOR THE SELECTION OF RAPID PROTOTYPING TECHNOLOGIES FOR INVESTMENT-CAST GAS TURBINE PARTS.
Creator
Gallagher, Angela, Geiger, Christopher, University of Central Florida
Abstract / Description
In the power generation sector, more specifically, the gas turbine industry, competition has forced the lead time-to-market for product advancements to be more important than ever. For design engineers, this means that product design iterations and final product development must be completed within both critical time windows and budgetary constraints. Therefore, two areas that have received significant attention in the research and in practice are: (1) rapid prototyping technology development...
Show moreIn the power generation sector, more specifically, the gas turbine industry, competition has forced the lead time-to-market for product advancements to be more important than ever. For design engineers, this means that product design iterations and final product development must be completed within both critical time windows and budgetary constraints. Therefore, two areas that have received significant attention in the research and in practice are: (1) rapid prototyping technology development, and (2) rapid prototyping technology selection. Rapid prototyping technology selection is the focus of this research. In practice, selecting the rapid prototyping method that is acceptable for a specific design application is a daunting task. With technological advancements in both rapid prototyping and conventional machining methods, it is difficult for both a novice design engineer as well as an experienced design engineer to decide not only what rapid prototyping method could be applicable, but also if a rapid prototyping method would even be advantageous over a more conventional machining method and where in the manufacturing process any of these processes would be utilized. This research proposes an expert system that assists a design engineer through the decision process relating to the investment casting of a superalloy gas turbine engine component. Investment casting is a well-known technique for the production of many superalloy gas turbine parts such as gas turbine blades and vanes. In fact, investment-cast turbine blades remain the state of the art in gas turbine blade design. The proposed automated expert system allows the engineer to effectively assess rapid prototyping opportunities for desired gas turbine blade application. The system serves as a starting point in presenting an engineer with commercially-available state-of-the-art rapid prototyping options, brief explanations of each option and the advantages and disadvantages of each option. It is not intended to suggest an optimal solution as there is not only one unique answer. For instance, cost and time factors vary depending upon the individual needs of a company at any particular time as well as existing strategic partnerships with particular foundries and vendors. The performance of the proposed expert system is assessed using two real-world case studies. The first case study shows how the expert system can advise the design engineer when suggesting rapid manufacturing in place of investment casting. The second case study shows how rapid prototyping can be used for creating part patterns for use within the investment casting process. The results from these case studies are telling in that their implementations potentially result in an 82 to 94% reduction in design decision lead time and a 92 to 97% cost savings.
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Date Issued
2010
Identifier
CFE0003338, ucf:48469
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFE0003338
Developing a Group Decision Support System (GDSS) for decision making under uncertainty
Title
Developing a Group Decision Support System (GDSS) for decision making under uncertainty.
Creator
Mokhtari, Soroush, Abdel-Aty, Mohamed, Madani Larijani, Kaveh, Wang, Dingbao, Xanthopoulos, Petros, University of Central Florida
Abstract / Description
Multi-Criteria Decision Making (MCDM) problems are often associated with tradeoffs between performances of the available alternative solutions under decision making criteria. These problems become more complex when performances are associated with uncertainty. This study proposes a stochastic MCDM procedure that can handle uncertainty in MCDM problems. The proposed method coverts a stochastic MCDM problem into many deterministic ones through a Monte-Carlo (MC) selection. Each deterministic...
Show moreMulti-Criteria Decision Making (MCDM) problems are often associated with tradeoffs between performances of the available alternative solutions under decision making criteria. These problems become more complex when performances are associated with uncertainty. This study proposes a stochastic MCDM procedure that can handle uncertainty in MCDM problems. The proposed method coverts a stochastic MCDM problem into many deterministic ones through a Monte-Carlo (MC) selection. Each deterministic problem is then solved using a range of MCDM methods and the ranking order of the alternatives is established for each deterministic MCDM. The final ranking of the alternatives can be determined based on winning probabilities and ranking distribution of the alternatives. Ranking probability distributions can help the decision-maker understand the risk associated with the overall ranking of the options. Therefore, the final selection of the best alternative can be affected by the risk tolerance of the decision-makers. A Group Decision Support System (GDSS) is developed here with a user-friendly interface to facilitate the application of the proposed MC-MCDM approach in real-world multi-participant decision making for an average user. The GDSS uses a range of decision making methods to increase the robustness of the decision analysis outputs and to help understand the sensitivity of the results to level of cooperation among the decision-makers. The decision analysis methods included in the GDSS are: 1) conventional MCDM methods (Maximin, Lexicographic, TOPSIS, SAW and Dominance), appropriate when there is a high cooperation level among the decision-makers; 2) social choice rules or voting methods (Condorcet Choice, Borda scoring, Plurality, Anti-Plurality, Median Voting, Hare System of voting, Majoritarian Compromise ,and Condorcet Practical), appropriate for cases with medium cooperation level among the decision-makers; and 3) Fallback Bargaining methods (Unanimity, Q-Approval and Fallback Bargaining with Impasse), appropriate for cases with non-cooperative decision-makers. To underline the utility of the proposed method and the developed GDSS in providing valuable insights into real-world hydro-environmental group decision making, the GDSS is applied to a benchmark example, namely the California's Sacramento-San Joaquin Delta decision making problem. The implications of GDSS' outputs (winning probabilities and ranking distributions) are discussed. Findings are compared with those of previous studies, which used other methods to solve this problem, to highlight the sensitivity of the results to the choice of decision analysis methods and/or different cooperation levels among the decision-makers.
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Date Issued
2013
Identifier
CFE0004723, ucf:49821
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFE0004723
RULE-BASED DECISION SUPPORT SYSTEM FOR SENSOR DEPLOYMENT IN DRINKING WATER NETWORKS
Title
RULE-BASED DECISION SUPPORT SYSTEM FOR SENSOR DEPLOYMENT IN DRINKING WATER NETWORKS.
Creator
Prapinpongsanone, Natthaphon, Chang, Ni-Bin, University of Central Florida
Abstract / Description
Drinking water distribution systems are inherently vulnerable to malicious contaminant events with environmental health concerns such as total trihalomethanes (TTHMs), lead, and chlorine residual. In response to the needs for long-term monitoring, one of the most significant challenges currently facing the water industry is to investigate the sensor placement strategies with modern concepts of and approaches to risk management. This study develops a Rule-based Decision Support System (RBDSS)...
Show moreDrinking water distribution systems are inherently vulnerable to malicious contaminant events with environmental health concerns such as total trihalomethanes (TTHMs), lead, and chlorine residual. In response to the needs for long-term monitoring, one of the most significant challenges currently facing the water industry is to investigate the sensor placement strategies with modern concepts of and approaches to risk management. This study develops a Rule-based Decision Support System (RBDSS) to generate sensor deployment strategies with no computational burden as we oftentimes encountered via large-scale optimization analyses. Three rules were derived to address the efficacy and efficiency characteristics and they include: 1) intensity, 2) accessibility, and 3) complexity rules. To retrieve the information of population exposure, the well-calibrated EPANET model was applied for the purpose of demonstration of vulnerability assessment. Graph theory was applied to retrieve the implication of complexity rule eliminating the need to deal with temporal variability. In case study 1, implementation potential was assessed by using a small-scale drinking water network in rural Kentucky, the United States with the sensitivity analysis. The RBDSS was also applied to two networks, a small-scale and large-scale network, in "The Battle of the Water Sensor Network" (BWSN) in order to compare its performances with the other models. In case study 2, the RBDSS has been modified by implementing four objective indexes, the expected time of detection (Z1), the expected population affected prior to detection (Z2), the expected consumption of contaminant water prior to detection, and the detection likelihood (Z4), are being used to evaluate RBDSS's performance and compare to other models in Network 1 analysis in BWSN. Lastly, the implementation of weighted optimization is applied to the large water distribution analysis in case study 3, Network 2 in BWSN.
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Date Issued
2011
Identifier
CFE0003704, ucf:48825
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFE0003704
A real-time crane service scheduling decision support system (CSS-DSS) for construction tower cranes
Title
A real-time crane service scheduling decision support system (CSS-DSS) for construction tower cranes.
Creator
Zavichi Tork, Amir, Madani Larijani, Kaveh, Oloufa, Amr, Tatari, Mehmet, Xanthopoulos, Petros, University of Central Florida
Abstract / Description
The success of construction projects depends on proper use of construction equipment and machinery to a great extent. Thus, appropriate planning and control of the activities that rely on construction equipment could have significant effects on improving the efficiency of project operations. Cranes are the largest and most conspicuous construction equipment, widely used in typical construction sites. They play a major role in relocation of materials in horizontal and vertical directions on...
Show moreThe success of construction projects depends on proper use of construction equipment and machinery to a great extent. Thus, appropriate planning and control of the activities that rely on construction equipment could have significant effects on improving the efficiency of project operations. Cranes are the largest and most conspicuous construction equipment, widely used in typical construction sites. They play a major role in relocation of materials in horizontal and vertical directions on construction sites. Given the nature of activities relying on construction cranes in various stages of a project, cranes normally have control over the critical path of the project with the potential to create schedule bottlenecks and delaying the completion of the project. This dissertation intends to improve crane operations efficiency by developing a new framework for optimizing crane service sequence schedule. The crane service sequence problem is mathematically formulated as an NP-complete optimization problem based on the well-known Travel Salesman Problem (TSP) and is solved using different optimization techniques depending on the problem's size and complexity. The proposed framework sets the basis for developing near-real time decision support tools for on-site optimization of crane operations sequence. To underline the value of the proposed crane sequence optimization methods, these methods are employed to solve several numerical examples. Results show that the proposed method can create a travel time saving of 28% on average in comparison with conventional scheduling methods such as First in First out (FIFO), Shortest Job First (SJF), and Earliest Deadline First (EDF).
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Date Issued
2013
Identifier
CFE0005078, ucf:50738
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFE0005078
Role Ambiguity: Defining the Elusive Role of the Special Education Teacher Who Works in Inclusive Settings
Title
Role Ambiguity: Defining the Elusive Role of the Special Education Teacher Who Works in Inclusive Settings.
Creator
Slanda, Dena, Little, Mary, Martin, Suzanne, Pearl, Cynthia, Boote, David, University of Central Florida
Abstract / Description
This phenomenological study examined the lived experiences of special education teachers who worked in inclusive settings. Given the increasing number of students with disabilities receiving special education services in the general education classroom (U.S. Department of Education, 2016), there is a critical need to understand the dynamic role of a special education teacher who works in inclusive settings. Federal mandates have required special education teachers working in inclusive...
Show moreThis phenomenological study examined the lived experiences of special education teachers who worked in inclusive settings. Given the increasing number of students with disabilities receiving special education services in the general education classroom (U.S. Department of Education, 2016), there is a critical need to understand the dynamic role of a special education teacher who works in inclusive settings. Federal mandates have required special education teachers working in inclusive settings to rethink their roles (McLeskey, Landers, Hoppey, (&) Williamson, 2011) and restructure their approach to providing specially-designed services. Further, these roles are dependent on those who interpret and implement policy and access to finite resources. This study used a phenomenological research method to examine the roles and responsibilities of special education teachers. Semi-structured interviews were conducted with seven participants (N = 7). A thematic analysis resulted in five overarching themes. The five themes included: (a) supporting students with disabilities within a support facilitation model; (b) role ambiguity of the special education teacher; (c) the lack of roles and responsibilities of the special education teacher within the MTSS framework; (d) the changing role of collaboration and communication; and (e) the challenges impacting the inclusion of students with disabilities in the general education setting. This study exposed the multiple facets of school and district policies that directly affected special educators' roles and responsibilities, as well as the emergence of a new role as a support facilitator.
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Date Issued
2017
Identifier
CFE0006796, ucf:51821
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFE0006796