Task 2: Engage International Expert Panel

The research team will form an international expert panel comprised of researchers with outstanding track records in freight demand modeling in countries with traditions of freight demand modeling research and practice. This expert panel will provide valuable information on practices and research in truck traffic forecasting for design in other countries; and (2) to get feedback on the research conducted by the team and proposed solutions.

The research team will submit a proposed roster of International Experts with their qualifications to NCHRP and panelists for their consideration. The team will make changes to the roster as needed and schedule one or more telephone or virtual conference meetings with the experts to discuss the project and obtain input. The meeting will be documented and submitted to the panel.  

Deliverables: Meeting minutes of International Expert Panel meeting to be sent to the panel.

Task 3: Identify User Needs and Practices

The team will plan and conduct three sets of engagement activities designed to gain insight into the needs, expectations, concerns, existing resources, and barriers for the various users producing and using truck traffic forecasts.  The engagement will generate insight from potential users of the research to be conducted with a wide range of state departments of transportation (DOTs) and private sector developers on their specific design needs as well as the resources available and needed for the development and use of truck traffic forecasts.

As part of this effort, the team will conduct the following activities:

Task 3.1 Conduct In-Depth Interviews (IDI):

·        Design and validate the IDI script.

·        Enlist the support of the project panel, AASHTO, AMPO, and private-sector contacts to identify appropriate interviewees.

·        Obtain NCHRP approval of the interview script and the list of interviewees.

·        Conduct IDIs to gain insights into questions related to the limitations of current truck traffic forecasting techniques; gaps between the needs in terms of truck traffic forecasts and the capability of current modeling techniques to produce sound estimates of the design inputs needed; and other concerns, expectations, challenges and opportunities.

Task 3.2 Survey Potential Users:

·        Design and validate the survey questionnaire. NCHRP approval of the questionnaire is required in advance of issuing the survey.  

·        Enlist the support of the project panel, AASHTO, AMPO, and private-sector developers to identify and disseminate the survey among public and private-sector professionals with expertise in and/or responsibility for truck traffic forecasting to support design.

·        Conduct online surveys to assess the needs and constraints among the various user groups.

·        Analyze the survey data and document the results.

Task 3.3 Identify Potential Participants for Virtual Workshop (Task 10):

This task provides the first steps of developing a list of participants to review the draft products in Task 10.  The following steps will be used:

·        The team will enlist the support of the project panel, AASHTO, AMPO, and private-sector contacts to identify appropriate invitees.

·        Produce a draft selection of potential invitees, and a list of replacements.

·        Develop a draft workshop agenda and format. 

·        Get feedback from the project panel on the workshop plan, including the list of invitees, and the agenda and format of the workshop.  

Deliverables: Documentation of Survey process and results; In-Depth Interview (IDI) script, List of interviewees, Draft questionnaire, and data analysis; Workshop plan with list of invitees

Task 4: Identify Design Scenarios and Design Inputs

Building on the results of Task 3, the team will define and catalog a series of design scenarios and identify truck traffic design inputs that are currently being used to influence design decision-making for each scenario. The scenarios will encapsulate common design challenges that require significant freight integration or considerations to produce a comprehensive catalog of engineering design scenarios—both public and private sector—together with identification of the corresponding truck traffic design inputs. Further, the scenarios will be designed to capture a broad spectrum of freight-related design needs, with the intention of informing future freight modeling efforts.

Once the design scenarios are identified, they will be organized into a matrix to identify the freight-related impacts of each scenario, and by defining the impacts, inputs will be identified that are currently used or could improve the outcome of each design scenario. This matrix will provide the basis for analysis later in this project to define where modelers should focus their efforts to improve the information available to designers to help them make decisions.

Deliverables: Tech memo with design scenarios, matrix of design needs/potential inputs.

Task 5: Synthesize Practice, Data, and Research Literature

The team will conduct an in-depth and comprehensive review of research and other literature documenting the current state of domestic and international practice, the data used in these efforts, and research in freight demand modeling.  The synthesis will cover technical reports and documents, journal articles, web pages, and all other possible sources. Special attention will be paid to the Traffic Monitoring Guide, and reports sponsored by NCHRP, NCFRP, and SHRP/SHRP2.

The team will review these documents as inputs to a systematic analysis of freight demand modeling practice and the data used. To conduct the analyses, the team will create a typology of freight demand applications and data use and summarize the research literature on freight demand modeling to identify potential ways to develop new techniques to improve the quality of truck traffic forecasts, focused on applications for a design context.

To organize the synthesis of modeling techniques, the team will analyze the references identified using a set of relevant descriptors that characterize the different freight demand models and techniques. These descriptors consider the model structure, the freight processes considered, geography, data used, and other factors as revealed in the literature.

Deliverable: The team will document the literature review in a technical report that summarizes the key findings of the review and analysis.

Task 6: Qualitatively Assess Data and Techniques

The research team will conduct a qualitative assessment of the wide range of modeling techniques identified in Task 5 to produce sound forecasts of truck traffic. This assessment will identify the key features of current freight demand modeling techniques, and qualitatively assess how these features influence the ability of the models to produce sound estimates of the various forms of truck traffic forecasts needed for engineering design. 

This task will have two major components: (1) an analysis of the model features that foster, or hinder, the ability of a given model to produce the truck traffic forecasts needed by the wide range of engineering design scenarios; and (2) a summary assessment of the overall ability of the model to forecast the various types of truck traffic forecasts—total truck traffic, truck traffic by time of day, among others needed for engineering design. The intent is to analyze how the model characteristics influence the ability to produce sound forecasts of truck traffic. The analyses in this task will be a key input to the research in Phase II, where a subset of the modeling techniques will be selected for quantitative performance analyses.

Deliverable: Technical report outlining the process followed in the data and technique assessment and key findings.

Task 7: Interim Report

The research team will compile an Interim Report that summarizes the work conducted and the conclusions reached in Tasks 1 through 6; and describes the tasks to be conducted in Phase II in sufficient detail to enable the Panel to fully comprehend the work to be conducted by the team.

The first part of the Interim Report will summarize the work of Tasks 1 through 6. The report will summarize the work done, challenges and obstacles encountered, key conclusions of the research conducted, and how these conclusions influence the design of the tasks to be conducted in Phase II.

The second part of the Interim Report will:

(1) Produce a detailed plan for testing the ability of key freight demand modeling techniques to produce the needed truck traffic design inputs. The tasks will be described in sufficient level of detail so that Panel members are able to understand the rationale and feasibility of the proposed work.

(2) Provide an outline of the Guide and other deliverables with brief descriptions of the contents.

(3) Include a list of potential participants in the Virtual Workshop where project products will be reviewed by potential users.

Products: Interim report and presentation materials for the interim meeting.

PHASE II

Task 8: Quantitatively Assess Data and Modeling Techniques, Identify Improvements

The research team will apply a practical and rigorous process to quantify the forecasting performance of alternative freight demand modeling techniques under different scenarios. This will be done (1) to provide a solid quantitative assessment of the key freight demand modeling techniques used in the US; and (2) identify immediate-term practical improvements, as well as medium/long-term ones, that could enhance the capabilities to forecast truck traffic design inputs.

This effort will help the team reach conclusions about the strengths and weaknesses of the key freight demand modeling techniques, enabling the identification of immediate improvements to these techniques, and recommending potential improvements in the medium and long terms.

Deliverables: Technical report summarizing: (1) the key results concerning the forecasting performance of the various freight demand modeling techniques, for various engineering design scenarios; and (2) a list of immediate-term practical improvements, and medium/long-term research suggestions.

Task 9: Develop Draft Guide and the Materials for the Virtual Workshop

Using the information generated from the research conducted in the early stages of the research (Tasks 1-8) the research team shall synthesize the best performing practices of forecasting truck traffic design inputs into a guide that includes an actionable set of technical procedures and direction on the use of the data currently available in the US targeting State DOT and other practitioners. These products will be tested in the stakeholder workshop described in Task 10.

Deliverables: Draft guide and other products for testing.

Task 10: Virtual Workshop with Potential Users

The team will organize a Virtual Workshop with potential users of project products to assess whether the project products are in line with the users’ expectations and needs. The workshop participants will represent the wide range of potential users, selected through the engagement conducted in Task 3.

The research team will prepare an agenda and materials for the Workshop for review and comment by NCHRP. The workshop will be scheduled and executed by the research team. The workshop will be fully documented in a summary memorandum. 

Deliverables: Summary memorandum describing the workshop format, the participants, and input provided on the draft guide and other shared deliverables by participants.

Task 11: Final Deliverables

Based on the feedback from the panel on interim report as well as input obtained by stakeholders during the virtual workshop, the team will produce the draft versions of all deliverables for review and comment by NCHRP and the panel.

Based on the feedback provided by the panel and NCHRP, the team will revise and prepare final deliverables for publication by NCHRP.

Deliverables: Final Contractor’s Report, Guide to the Development and Use of Truck Traffic Forecasts in Design, and an Implementation Plan (see Special Note below).