An average of 6.5 million crashes are reported to the police every year in the United States. Safety is significantly important considering the rapid increase on traffic volume on American roads. This thesis describes the development of a safety model whose primary objective is to capture the benefits of Intelligent Transportation Systems (ITS) on safety. The specific ITS component that is examined in more detail is traffic signal coordination. The model was tested in a micro-simulation environment using INTEGRATION traffic simulation model as well as in a field data evaluation. The General Estimates System (GES) database was chosen as the primary national database to extract accident data. These data were used for the development of the statistical foundation for the safety model. Crash rates were produced using extracted crash frequencies and annual vehicle miles traveled figures from the Highway Statistics (FHWA, 1997). Regression analysis was performed to predict the behavior of several crash types, as they were associated with a variety of variables, for example the facility speed limit and time the crash occurred. The model was developed in FORTRAN code that estimates the accident risk of a facility based on its free-speed. Two methods were used to test the model: 1. field data from the city of Phoenix, Arizona were used in a GPS (Global Positioning Systems) floating car that tracked the accident risk on a second by second basis. Before and after signal coordination scenarios were tested thus yielding a result that the accident risk is less in the after scenario. 2. the model was then tested in a micro-simulation environment using the INTEGRATION traffic model. A hypothetical network, as well as the Scottsdale/Rural road corridor in Phoenix were used. The sensitivity analysis of before and after signal coordination scenarios indicated that after the signals were coordinated, the crash risk was lower, thus proving that the model could capture the benefits of this ITS component. Reducing the number of crashes is an important aspect of improving safety. Traffic signal coordination smoothens traffic on a facility and reduces its potential accident risk by producing less vehicle-to vehicle interactions. Also, traffic signal control increases the free-speed of a facility. The advantage of this safety model is the fact that it can be used to capture a variety of ITS technologies and not only signal coordination that is examined in more detail in this thesis. / Master of Science

The purpose of this basic qualitative study was to examine the perceptions of school leaders, school division leaders, and non-SRO model employees regarding the transition from a school safety model with School Resource Officers (SROs) to a model with non-SRO (NSRO) employees in one urban school division in Virginia. The researcher sought to answer one research question: What are school leaders' and non-School Resource Officer employees' perceptions of the transition from a school safety model with School Resource Officers to a model with non-SRO employees? The researcher used interviews, an NSRO observation, and the content analysis of school division documents to learn about the school leaders', school division leaders', and NSRO employees' perceptions of the transition to the new school safety model. The study sample included two school leaders, six school division leaders, and three NSRO employees of the school division. The six findings from the study revealed: (a) challenges related to the process of the transition to the new school safety model, (b) challenges with communication and response time with emergency services, (c) the roles of NSROs are inconsistent, (d) similarities between SROs and NSROs, (e) school and school division leaders reported common contributing factors of the transition to the new school safety model, and (f) school leaders indicated concerns regarding a lack of SROs, whereas most school division leaders did not report being concerned about a lack of SROs. This study also proposed implications for school divisions and schools that may consider changing their school safety model. / Doctor of Education / The purpose of this qualitative study was to examine the perceptions of principals, school division central office employees, the school division superintendent, and non-School Resource Officer (NSRO) employees regarding the transition from a school safety model that had School Resource Officers (SRO) to a new school safety model with NSROs. The researcher interviewed two principals, five central office employees, the school division superintendent, and three NSRO employees to answer the study's research question: What are school leaders' and non-School Resource Officer employees' perceptions of the transition from a school safety model with School Resource Officers to a model with non-SRO employees? The researcher also observed one NSRO and reviewed publicly available documents related to the school division's transition to the new school safety model. This study had six findings: (a) challenges with the process of the transition to the new school safety model, (b) challenges with communication and response time with the police and fire departments, (c) inconsistency with the roles of NSROs, (d) similarities between SROs and NSROs, (e) common reports of contributing factors of the transition to the new school safety model between school and school division leaders, and (f) school leaders reported concerns regarding a lack of SROs, but most school division leaders did not report being concerned about a lack of SROs. This study also included implications for school divisions and schools that may consider changing their school safety model.