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12 The research results do serve to introduce a structured and studies. Chapter 5 presents the results of the field studies per- measurable framework for quantifying the chief operational formed under the auspices of this project. Chapter 6 presents parameters of accessibility (Schroeder et al. 2009) and to estab- efforts to extend the field results to other locations and geome- lish decision support through empirical research results. How- tries through statistical modeling and simulation-based analy- ever, the results do not provide a comprehensive evaluation of sis approaches. Finally, Chapter 7 presents an interpretation all potential treatments and all variations of sites. Such effort of the results and conclusions of the research effort. The report is considered well beyond the scope and budget of a single further contains significant supplemental materials in sev- project. The authors do hope, however, that the reader will eral appendices. The reader is referred to this supplemental find the research findings and discussions in this document material directly from the discussion in the different chap- useful and that the results provide a common baseline for dis- ters. In total, fourteen appendices are provided: cussion of questions of accessibility at these locations. The establishment of a common language between the engineer- Appendix A presents detailed analysis results for all field ing, accessibility, and policy communities is an important first studies conducted through NCHRP Project 3-78A. step in approaching a common challenge. This report hopes Appendix B provides additional detail on the long list of to provide this language. treatments considered in this research. Appendix C provides results of the internal team treat- ment survey that was used to narrow the initial long list Content of This Report of treatments to a short list of treatments recommended The basic outline of this report follows the sequence of for field testing. study used by the team to conduct the research. After an ini- Appendix D gives details on site selection, including pho- tial review of the literature and pre-existing knowledge base, tographs of other locations considered for this research. the availability of actual treatments is discussed. This includes Appendix E presents details on treatment installations and a process for narrowing down a long list of treatment alterna- further descriptions of the NCHRP Project 3-78A test sites. tives to a succinct and well-targeted short list of solutions that Appendix F gives specific details on the pedestrian hybrid maximize the efficiency of limited project resources. Following beacon (PHB) installation at the two-lane roundabout in treatment identification, test sites were selected from a data- Golden, CO, including signal timing plans and other tim- base of sites available for treatment installation. The geometry, ing details. traffic volumes, availability of resources (team and municipal), Appendix G includes the blank participant survey forms and team judgments based on experience were applied in used for participant questionnaires following each study. deciding which locations should be used for treatment instal- Appendix H presents details on a team-internal-conflict lations. Field trials were conducted using a focused experimen- survey of crossing events at the CTL location intended to tal design approved by the Institutional Review Board (IRB) verify the viability of the orientation and mobility (O&M) of Western Michigan University that used blind study partic- intervention safety measure. ipants at various locations. Field results were analyzed using a Appendix I presents further details on the simulation analy- newly developed analysis framework that highlights the differ- sis framework in the form of a paper presented by members ent aspects of the crossing task and allows for a target's appli- of the research team. cation and evaluation of treatment effects. Finally, the results Appendix J presents details on development of the accessi- were interpreted and extended to other applications using sta- bility measures used in the analysis framework in the form tistical modeling and discussion of simulation-based analysis of a paper presented by members of the research team. approaches. Appendix K presents details on the development of pedes- The report is organized as follows: After the general intro- trian delay models in the form of a paper presented by duction in this chapter, Chapter 2 gives an overview of the members of the research team. literature and background information on the question of Appendix L presents details on a simulation-based evalu- pedestrian accessibility to complex intersections. Chapter 3 ation of roundabout signalization treatments in the form presents a methodology for identifying potential treatment of a paper presented by members of the research team. solutions and discusses the data collection approach used in Appendix M discusses the use of visualization techniques this research. It further presents the process used to select in NCHRP Project 3-78A in the form of a paper presented treatment sites and provides narrative descriptions of these by members of the research team. locations. Chapter 4 presents an analysis framework for quan- Appendix N presents the completed and signed IRB approval tifying pedestrian accessibility. This framework guides the forms for this research along with the blank consent forms analysis in this document and is generally applicable to other signed by all participants.