Current Search: risk model (x)
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(1 - 8 of 8)
- Title
- The Unacceptable Rise: An Investigation of School Shootings in the United States.
- Creator
-
Gulliford, Tracy, Sellnow, Deanna, Sellnow, Timothy, Spence, Patric, University of Central Florida
- Abstract / Description
-
This research study examined teachers` understanding of risk factors and characteristics of potential perpetrators of school shootings, as well as the steps to take when they are identified in students. Participants completed a survey that contained Likert-type scale items regarding selfefficacy and open-ended questions regarding school violence experiences. A mixed methods analysis revealed three primary conclusions. First, teachers have high levels of self-efficacy regarding the importance...
Show moreThis research study examined teachers` understanding of risk factors and characteristics of potential perpetrators of school shootings, as well as the steps to take when they are identified in students. Participants completed a survey that contained Likert-type scale items regarding selfefficacy and open-ended questions regarding school violence experiences. A mixed methods analysis revealed three primary conclusions. First, teachers have high levels of self-efficacy regarding the importance of and ability to deal effectively with troubled students. This conclusion suggests that teachers do internalize the relevance of this issue to them. Second, this study revealed a gap in terms of the explanation and distribution component of the IDEA model. More specifically, teachers are under-informed about how to identify characteristics of potential perpetrators and what forces may influence them to engage in school violence. Third, this study revealed a need for additional modes through which training modules and sessions should be distributed to prepare teachers to dissuade violent acts from occurring in their classrooms and schools.
Show less - Date Issued
- 2019
- Identifier
- CFE0007644, ucf:52486
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0007644
- Title
- Modeling Risk for Sexually Transmitted Infections in Women in a Court-Ordered Substance Treatment Program.
- Creator
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Deavers, Frances, Cassisi, Jeffrey, Bowers, Clint, Eldridge, Gloria, University of Central Florida
- Abstract / Description
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Developing a comprehensive model of Sexually Transmitted Infection (STI) risk factors and their inter-relationships is vital to improving methods of risk identification and treatment delivery. The CDC posed three general categories that may serve as a framework for such a model: sexual network, individual behavior, and social/ structural risk. None of the extant risk models incorporate measures from all three categories. Additionally, none of these models, generally focused on individual...
Show moreDeveloping a comprehensive model of Sexually Transmitted Infection (STI) risk factors and their inter-relationships is vital to improving methods of risk identification and treatment delivery. The CDC posed three general categories that may serve as a framework for such a model: sexual network, individual behavior, and social/ structural risk. None of the extant risk models incorporate measures from all three categories. Additionally, none of these models, generally focused on individual behavior, use medical data on infection as their outcome variable. This is problematic because the ultimate outcome of infection is also influenced by sexual network and social/ structural variables, in addition to individual behaviors. Therefore the current study aimed to develop a comprehensive model of risk incorporating sexual network, individual behavior, and social/ structural risk variables, using medical data on infection status as the outcome variable. The sample consisted of 506 women in a court-ordered substance treatment program. An Exploratory Factor Analysis provided preliminary evidence for a three factor model corresponding to the CDC framework. However, a Confirmatory Factor Analysis failed to confirm this model. Additionally, a logistic regression suggested that this model has limited clinical utility for this sample. Future studies may more conclusively determine the importance of various STI risk variables, the relationships between them, and whether they mirror the CDC theoretical framework. With rates of infection still high in the United States, and even increasing among women for certain STIs, this is a critical public health issue that should continue to be examined.
Show less - Date Issued
- 2014
- Identifier
- CFE0005323, ucf:50502
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0005323
- Title
- OCCUPATIONAL LOWER EXTREMITY RISK ASSESSMENT MODELING.
- Creator
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Reid, Christopher, McCauley-Bush, Pamela, University of Central Florida
- Abstract / Description
-
Introduction: Lower extremity (LE) work-related musculoskeletal disorders (WMSDs) are known to occur with cumulative exposure to occupational and personal risks. The objective of this dissertation study was to find if creating a quantifiable risk detection model for the LE was feasible. The primary product of the literature review conducted for this study resulted in focusing the attention of the model development process onto creating the initial model of the LE for assessing knee disorder...
Show moreIntroduction: Lower extremity (LE) work-related musculoskeletal disorders (WMSDs) are known to occur with cumulative exposure to occupational and personal risks. The objective of this dissertation study was to find if creating a quantifiable risk detection model for the LE was feasible. The primary product of the literature review conducted for this study resulted in focusing the attention of the model development process onto creating the initial model of the LE for assessing knee disorder risk factors. Literature Review: LE occupational disorders affect numerous industries and thousands of people each year by affecting any one of the musculoskeletal systems deemed susceptible by the occupational and personal risk factors involved. Industries known to be affected tend to have labor intensive job descriptions. Some of the numerous industry examples include mining, manufacturing, firefighting, and carpet laying. Types of WMSDs noticed by the literature include bursitis, osteoarthritis, stress fractures, tissue inflammation, and nerve entrapment. In addition to the occupationally related disorders that may develop, occupationally related discomforts were also taken into consideration by this study. Generally, both the disorders and the discomforts can be traced to either a personal or occupational risk factor or both. Personal risk factors noted by the literature include a person's physical fitness and health history (such as past injuries). Meanwhile, occupational risks can be generalized to physical postures, activities, and even joint angles. Prevalence data over a three year interval (2003-2005) has found that LE WMSDs make up on average approximately 7.5% of all the WMSD cases reported to the US Occupational Safety and Health Administration (OSHA). When the literature is refined to the information pertaining to occupational knee disorders, the mean prevalence percentage of the same three year range is about 5%. Mean cost for knee injuries were found to be $18,495 (for the year between 2003 and 2004). Methodology: Developing a risk model for the knee meant using groups of subject matter experts for model development and task hazard analysis. Sample occupational risk data also needed to be gathered for each of a series of tasks so that the model could be validated. These sample data were collected from a sample aircraft assembly plant of a US aerospace manufacturer. Results: Based on the disorder and risk data found in the literature, a knee risk assessment model was developed to utilize observational, questionnaire, and direct measure data collection methods. The final version of this study's knee model has an inventory of 11 risk factors (8 occupational and 3 personal) each with varying degrees of risk exposure thresholds (e.g., high risk, moderate risk, or minimal risk). For the occupational risk assessment portion of the model, the results of task evaluations include both an occupational risk resultant score (risk score) and a task risk level (safe or hazardous). This set of results is also available for a cumulative (whole day) assessment. The personal risk assessment portion only produces a risk resultant score. Validation of the knee risk model reveals statistically (t (34) = 1.512, p = 0.156), that it is functioning as it should and can decide between hazardous and safe tasks. Additionally, the model is also capable of analyzing tasks as a series of cumulative daily events and providing an occupational and personal risk overview for individuals. Conclusion: While the model proved to be functional to the given sample site and hypothetical situations, further studies are needed outside of the aerospace manufacturing environment to continue testing both the model's validity and applicability to other industrial environments. The iterative adjustments generated for the occupational risk portion of the model (to reduce false positives and negatives) will need additional studies that will further evaluate professional human judgment of knee risk against this model's results. Future investigations must also make subject matter experts aware of the minimal risk levels of this knee risk assessment model so that task observational results are equally comparable. Additional studies are moreover needed to assess the intimate nature between variable interactions; especially multiple model defined minimal risks within a single task.
Show less - Date Issued
- 2009
- Identifier
- CFE0002612, ucf:48289
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0002612
- Title
- USDA Instructional Risk Messages for High Pathogen Avian Influenza.
- Creator
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Jones, Jenna, Sellnow, Timothy, Littlefield, Robert, Sellnow, Deanna, Parrish, Adam, University of Central Florida
- Abstract / Description
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High Pathogen Avian Influenza (HPAI) is a highly contagious disease threatening United States poultry farms. The aim of this study is to examine the extent to which current instructional risk communication by the United States Department of Agriculture (USDA) meets the expectations of existing literature, particularly the IDEA model. This study examined two documents produced by the USDA for the ongoing threat of HPAI, the Red Book and the Defend the Flock campaign. The aim of the documents...
Show moreHigh Pathogen Avian Influenza (HPAI) is a highly contagious disease threatening United States poultry farms. The aim of this study is to examine the extent to which current instructional risk communication by the United States Department of Agriculture (USDA) meets the expectations of existing literature, particularly the IDEA model. This study examined two documents produced by the USDA for the ongoing threat of HPAI, the Red Book and the Defend the Flock campaign. The aim of the documents is to provide U.S. poultry farmers and the publics with knowledge and information about prevention and response to HPAI. The IDEA model was applied to serve as a framework to analyze how much of each component was present in the messaging. Specifically, the internalization, explanation, and action components were applied to the USDA documents.The documents were coded by two researchers. The researchers, using a codebook, examined the documents and assessed each section (Red Book) or slogan (Defend the Flock) for the presence or absence of three components of the IDEA model: internalization, explanation, and action. When discrepancies arose between the coders, they were resolved through discussion. The results indicated the majority of the Red Book was dedicated to the explanation component of the IDEA model. Conversely, the majority of the Defend the Flock campaign was identified as either internalization or action.The findings in this study can serve as lessons learned to help to improve the effectiveness of instructional risk messaging in similar crises. Specifically, this study recommends that messages be adapted to the intended audience to help them recognize their personal risks, that explanatory messages be intertwined with recommended actions, and that organizations and agencies consider following the USDA's lead and provide complementary materials. For example, some materials may be highly detailed while an accompanying document could provide a simple, brief overview of the risk and recommended actions.
Show less - Date Issued
- 2018
- Identifier
- CFE0007023, ucf:52045
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0007023
- Title
- A FRAMEWORK FOR THE ASSESSMENT AND ANALYSIS OF MULTI-HAZARDSINDUCED RISK RESULTING FROM SPACE VEHICLES OPERATIONS.
- Creator
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Sala-Diakanda, Serge, Rabelo, Luis, University of Central Florida
- Abstract / Description
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With the foreseeable increase in traffic frequency to and from orbit, the safe operation of current and future space vehicles at designated spaceports has become a serious concern. Due to their high explosive energy potential, operating those launch vehicles presents a real risk to: (1) the spaceport infrastructure and personnel, (2) the communities surrounding the spaceport and (3) the flying aircrafts whose routes could be relatively close to spaceport launch and reentry routes. Several...
Show moreWith the foreseeable increase in traffic frequency to and from orbit, the safe operation of current and future space vehicles at designated spaceports has become a serious concern. Due to their high explosive energy potential, operating those launch vehicles presents a real risk to: (1) the spaceport infrastructure and personnel, (2) the communities surrounding the spaceport and (3) the flying aircrafts whose routes could be relatively close to spaceport launch and reentry routes. Several computer models aimed at modeling the effects of the different hazards generated by the breakup of such vehicles (e.g., fragmentation of debris, release of toxic gases, propagation of blast waves, etc.) have been developed, and are used to assist in Go-No Go launch decisions. They can simulate a total failure scenario of the vehicle and, estimate a number of casualties to be expected as a result of such failure. However, as all of these models – which can be very elaborate and complex – consider only one specific explosion hazard in their simulations, the decision of whether or not a launch should occur is currently based on the evaluation of several estimates of an expected number of casualties. As such, current practices ignore the complex, nonlinear interactions between the different hazards as well as the interdependencies between the estimates. In this study, we developed a new framework which makes use of information fusion theory, hazards' dispersion modeling and, geographical statistical analysis and visualization capabilities of geographical information systems to assess the risk generated by the operation of space launch vehicles. A new risk metric, which effectively addresses the lack of a common risk metric with current methods, is also proposed. A case study, based on a proposed spaceport in the state of Oklahoma showed that the estimates we generate through our framework consistently outperform estimates provided by any individual hazard, or by the independent combination of those hazards. Furthermore, the study revealed that using anything else than fusion could provide seriously misleading results, with potentially catastrophic consequences.
Show less - Date Issued
- 2007
- Identifier
- CFE0001606, ucf:47178
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0001606
- Title
- DRIVING SIMULATOR VALIDATION AND REAR-END CRASH RISK ANALYSIS AT A SIGNALISED INTERSECTION.
- Creator
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Chilakapati, Praveen, Abdel-Aty, Mohamed, University of Central Florida
- Abstract / Description
-
In recent years the use of advanced driving simulators has increased in the transportation engineering field especially in evaluating safety countermeasures. The driving simulator at UCF is a high fidelity simulator with six degrees of freedom. This research aims at validating the simulator in terms of speed and safety with the intention of using it as a test bed for high risk locations and to use it in developing traffic safety countermeasures. The Simulator replicates a real world...
Show moreIn recent years the use of advanced driving simulators has increased in the transportation engineering field especially in evaluating safety countermeasures. The driving simulator at UCF is a high fidelity simulator with six degrees of freedom. This research aims at validating the simulator in terms of speed and safety with the intention of using it as a test bed for high risk locations and to use it in developing traffic safety countermeasures. The Simulator replicates a real world signalized intersection (Alafaya trail (SR-434) and Colonial Drive (SR-50)). A total of sixty one subjects of age ranging from sixteen to sixty years were recruited to drive the simulator for the experiment, which consists of eight scenarios. This research validates the driving simulator for speed, safety and visual aspects. Based on the overall comparisons of speed between the simulated results and the real world, it was concluded that the UCF driving simulator is a valid tool for traffic studies related to driving speed behavior. Based on statistical analysis conducted on the experiment results, it is concluded that SR-434 northbound right turn lane and SR-50 eastbound through lanes have a higher rear-end crash risk than that at SR-50 westbound right turn lane and SR-434 northbound through lanes, respectively. This conforms to the risk of rear-end crashes observed at the actual intersection. Therefore, the simulator is validated for using it as an effective tool for traffic safety studies to test high-risk intersection locations. The driving simulator is also validated for physical and visual aspects of the intersection as 87.10% of the subjects recognized the intersection and were of the opinion that the replicated intersection was good enough or realistic. A binary logistic regression model was estimated and was used to quantify the relative rear-end crash risk at through lanes. It was found that in terms of rear-end crash risk SR50 east- bound approach is 23.67% riskier than the SR434 north-bound approach.
Show less - Date Issued
- 2006
- Identifier
- CFE0001391, ucf:46964
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0001391
- Title
- Risk Management in Reservoir Operations in the Context of Undefined Competitive Consumption.
- Creator
-
Salami, Yunus, Nnadi, Fidelia, Wang, Dingbao, Chopra, Manoj, Rowney, Alexander, Divo, Eduardo, University of Central Florida
- Abstract / Description
-
Dams and reservoirs with multiple purposes require effective management to fully realize their purposes and maximize efficiency. For instance, a reservoir intended mainly for the purposes of flood control and hydropower generation may result in a system with primary objectives that conflict with each other. This is because higher hydraulic heads are required to achieve the hydropower generation objective while relatively lower reservoir levels are required to fulfill flood control objectives....
Show moreDams and reservoirs with multiple purposes require effective management to fully realize their purposes and maximize efficiency. For instance, a reservoir intended mainly for the purposes of flood control and hydropower generation may result in a system with primary objectives that conflict with each other. This is because higher hydraulic heads are required to achieve the hydropower generation objective while relatively lower reservoir levels are required to fulfill flood control objectives. Protracted imbalances between these two could increase the susceptibility of the system to risks of water shortage or flood, depending on inflow volumes and operational policy effectiveness. The magnitudes of these risks can become even more pronounced when upstream use of the river is unregulated and uncoordinated so that upstream consumptions and releases are arbitrary. As a result, safe operational practices and risk management alternatives must be structured after an improved understanding of historical and anticipated inflows, actual and speculative upstream uses, and the overall hydrology of catchments upstream of the reservoir. One of such systems with an almost yearly occurrence of floods and shortages due to both natural and anthropogenic factors is the dual reservoir system of Kainji and Jebba in Nigeria. To analyze and manage these risks, a methodology that combines a stochastic and deterministic approach was employed. Using methods outlined by Box and Jenkins (1976), autoregressive integrated moving average (ARIMA) models were developed for forecasting Niger river inflows at Kainji reservoir based on twenty-seven-year-long historical inflow data (1970-1996). These were then validated using seven-year inflow records (1997-2003). The model with the best correlation was a seasonal multiplicative ARIMA (2,1,1)x(2,1,2)12 model. Supplementary validation of this model was done with discharge rating curves developed for the inlet of the reservoir using in situ inflows and satellite altimetry data. By comparing net inflow volumes with storage deficit, flood and shortage risk factors at the reservoir were determined based on (a) actual inflows, (b) forecasted inflows (up to 2015), and (c) simulated scenarios depicting undefined competitive upstream consumption. Calculated high-risk years matched actual flood years again suggesting the reliability of the model. Monte Carlo simulations were then used to prescribe safe outflows and storage allocations in order to reduce futuristic risk factors. The theoretical safety levels achieved indicated risk factors below threshold values and showed that this methodology is a powerful tool for estimating and managing flood and shortage risks in reservoirs with undefined competitive upstream consumption.
Show less - Date Issued
- 2012
- Identifier
- CFE0004593, ucf:49193
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0004593
- Title
- Pedestrian Safety Analysis through Effective Exposure Measures and Examination of Injury Severity.
- Creator
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Shah, Md Imran, Abdel-Aty, Mohamed, Eluru, Naveen, Lee, JaeYoung, University of Central Florida
- Abstract / Description
-
Pedestrians are considered the most vulnerable road users who are directly exposed to traffic crashes. In 2014, there were 4,884 pedestrians killed and 65,000 injured in the United States. Pedestrian safety is a growing concern in the development of sustainable transportation system. But often it is found that safety analysis suffers from lack of accurate pedestrian trip information. In such cases, determining effective exposure measures is the most appropriate safety analysis approach. Also...
Show morePedestrians are considered the most vulnerable road users who are directly exposed to traffic crashes. In 2014, there were 4,884 pedestrians killed and 65,000 injured in the United States. Pedestrian safety is a growing concern in the development of sustainable transportation system. But often it is found that safety analysis suffers from lack of accurate pedestrian trip information. In such cases, determining effective exposure measures is the most appropriate safety analysis approach. Also it is very important to clearly understand the relationship between pedestrian injury severity and the factors contributing to higher injury severity. Accurate safety analysis can play a vital role in the development of appropriate safety countermeasures and policies for pedestrians.Since pedestrian volume data is the most important information in safety analysis but rarely available, the first part of the study aims at identifying surrogate measures for pedestrian exposure at intersections. A two-step process is implemented: the first step is the development of Tobit and Generalized Linear Models for predicting pedestrian trips (i.e., exposure models). In the second step, Negative Binomial and Zero Inflated Negative Binomial crash models were developed using the predicted pedestrian trips. The results indicate that among various exposure models the Tobit model performs the best in describing pedestrian exposure. The identified exposure relevant factors are the presence of schools, car-ownership, pavement condition, sidewalk width, bus ridership, intersection control type and presence of sidewalk barrier. The t-test and Wilcoxon signed-rank test results show that there is no significant difference between the observed and the predicted pedestrian trips. The process implemented can help in estimating reliable safety performance functions even when pedestrian trip data is unavailable.The second part of the study focuses on analyzing pedestrian injury severity for the nine counties in Central Florida. The study region covers the Orlando area which has the second-worst pedestrian death rate in the country. Since the dependent variable 'Injury' is ordinal, an 'Ordered Logit' model was developed to identify the factors of pedestrian injury severity. The explanatory variables can be classified as pedestrian/driver characteristics (e.g., age, gender, etc.), roadway traffic and geometric conditions (e.g.: shoulder presence, roadway speed etc.) and crash environment (e.g., light, road surface, work zone, etc.) characteristics. The results show that drug/alcohol involvement, pedestrians in a hurry, roadway speed limit 40 mph or more, dark condition (lighted and unlighted) and presence of elder pedestrians are the primary contributing factors of severe pedestrian crashes in Central Florida. Crashes within the presence of intersections and local roads result in lower injury severity. The area under the ROC (Receiver Operating Characteristic) curve has a value of 0.75 that indicates the model performs reasonably well. Finally the study validated the model using k-fold cross validation method. The results could be useful for transportation officials for further pedestrian safety analysis and taking the appropriate safety interventions.Walking is cost-effective, environmentally friendly and possesses significant health benefits. In order to get these benefits from walking, the most important task is to ensure safer roads for pedestrians.
Show less - Date Issued
- 2017
- Identifier
- CFE0006656, ucf:51224
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0006656
