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1. Introduction

1.1 Archived Data Management Systems

Archived Data Management Systems (ADMSs) are information management systems with decision support capabilities that implement the requirements found in the Archived Data User Service (ADUS). ADUS is one of 33 user services identified within the National ITS Architecture (henceforth, "the Architecture") that were created to document (in somewhat general terms) what an ITS application should do from the user's perspective. A broad range of users are considered, including the traveling public as well as many different types of system operators. User services form the basis of the Architecture development effort.

ADUS was developed as an addition to the original Architecture as a way to capture for later use real-time information used for ITS control strategies. One of the features of ADUS that distinguishes it from other user services is the large number (14) of stakeholder groups. These stakeholders include public transportation agency personnel (e.g., planners, air quality analysts, researchers, transit operators, and safety administrators) as well as private sector groups. By using archived ITS data, data collection costs for stakeholder applications can be reduced. Further, the detailed nature of ITS-generated data allow for more accurate analyses and make possible many applications that could not have been undertaken except at substantial cost. Figure 1 displays several examples of how a single subset of archived data - travel monitoring data - support ADUS stakeholder functions. ADUS relies on other ITS functions to provide data. This requires that close coordination be achieved with other ITS standard efforts.

Flow chart showing how one subset of archived data supports ADUS functions. At the top of the hierarchical flowchart is Real-Time ITS Sources, which flows down into Archived Data User Service, or Implementation. From there, the flow moves down to Travel Condition Data, which flows into Performance Monitoring, ATIS Functions, Operations Planning, Long-Range Planning, and Other Stakeholder Functions.
Figure 1. Archived Travel Monitoring Data Serve the Applications of Multiple Stakeholders

One of the stakeholder groups identified in the development of ADUS is operations personnel. They are crucial to the success of ADUS in that they control the collection of data that form the basis of the archives. Moreover, operations personnel are also major beneficiaries of ADUS. Early ADUS documents postulated that archived data would promote improved operations by helping to determine control strategies (e.g., timing of ramp meters and traffic signals; deployment of incident management equipment, etc.) and in evaluations of programs. While these original purposes remain valid, it is becoming increasingly clear that operations personnel will accrue additional benefits from ADUS as ADMSs become more widespread and grow in sophistication.

Several recent events have greatly increased the importance of ADUS for ITS deployments. First, the need to do Federal performance benchmarking as a way to track program effectiveness has been identified by FHWA. Second, related to Federal benchmarking is the provision of detailed data for operations planning. Operation of the transportation system has become the primary focus of many transportation organizations including FHWA and ITE. ADUS provides the highly detailed data necessary to do operations planning at a high resolution level (such as evaluations, performance measurement, and deployment adjustments), especially considering the expense of dedicated data collection efforts. Third, closing the Advanced Traveler Information System (ATIS) data gap and producing the next generation of ATIS products requires ADUS. A sound and detailed historical record of system performance is needed for ATIS purposes, especially as products become more sophisticated. For example, short-term congestion forecasts are seen as a highly marketable product, but these must rely on analysis of historical congestion trends to be credible.

As a user service, ADUS is a concept rather than a tangible system. As noted previously, an ADMS is the system that implements the concepts embedded in ADUS. At its core, an ADMS is an information management system that is actively maintained following standard information technology principles. Advanced forms of ADMSs may include applications that achieve the functionality of a decision support system, but their primary purpose is to collect, process (including quality control, aggregations, and data transformations), store, and disseminate data for a wide variety of existing and emerging applications.

1.2 Background On The TMC Applications Of Archived Data Operational Test

1.2.1 Project Goals

In 2002, FHWA awarded a field operational test to the Virginia Department of Transportation entitled (VDOT) Traffic Management Center (TMC) Applications of Archived Data Operational Test. The objective from the original Request for Application (RFA) was stated as:

The objective of this operational test is to study how transportation management center (TMC) operational practices and procedures can benefit through the applied use of archived data from highway-based and/or transit-based ITS sources. This effort will consider how specific TMC functions can be enhanced through performance measures and analytical techniques enabled through archived data. The results of this operational test will be used to support the development of guidance for applying archived data to enhance transportation management center operations, practices and procedures.

The intent of the operational test was to use archived data to effect transportation operations and management decisions. However, because an ADMS has value to a wide variety of stakeholders (14, as identified in the ADUS Standards Strategic Plan), the scope of ADMS Virginia was expanded to include applications for transportation planners as well as operators. The operational test was to build on current state of the practice in designing ADMSs.

With regard to operations, algorithms were to supporting various Advanced Traffic Management Systems (ATMS) and ATIS functions were to be considered. The RFA stated:

The ATMS and ATIS functions that may be supported include, but are not limited to, the following:

Performance measurement of TMC functions was also emphasized in the RFA. Since performance measurement overlaps with the activities of transportation planners, their inclusion in the development process was a natural extension of the project's scope:

[The project should...] Determine how the operational performance of the TMC changes as the archived data are applied. Although each TMC has unique operating characteristics, the operational performance can be gauged by establishing performance criteria. Examples of performance criteria may include, but are not limited to, the following:

1.2.2 Project Development

A team led by VDOT's ITS Division was selected to undertake this operational test. The project was named ADMS Virginia and this term is used throughout this report to reference the project. VDOT led the effort with a team that included the University of Virginia (UVA) Center for Transportation Studies (CTS) and George Mason University (GMU). UVA subcontracted the software development part of the project to Open Roads Consulting, Inc. (ORCI). The equipment necessary for the project is hosted at the Smart Travel Laboratory (STL), a joint facility of VDOT and UVA which is located on the campus of UVA.

ADMS Virginia was deployed starting with the Hampton Roads area. The Hampton Roads participants in the process included:

The project deployment was divided into four builds with incremental support of the above services, rather than a single system at the end of the project period. The build approach was used to identify important features of the system and the interface, and to apply the institutional and technical lessons learned in the early builds to later builds. Builds 1-3 concentrated on developing a fully operational ADMS for the Hampton Roads area, with each successive build adding new functions. Build 4 entailed the expansion of the ADMS to the Northern Virginia District of VDOT (NoVA), which is located in the Washington, D.C. Metropolitan area. Builds 1 through 3 completed the requirements of the original scope of work for the FOT. At the completion of Build 3, sufficient funds remained to support a fourth build. A proposal was submitted to and approved by FHWA to extend the project scope and end date to develop Build 4, extending the system to incorporate data from NoVA. The system functionality developed in Builds 1-3 was the same for both areas.

The four builds of the project may be summarized as:

Build 1

Build 2

Build 3

Build 4

UVA directed the software development effort with Open Roads providing the software engineering. Highlights of the development approach used by the project team included:

Diagram showing flow of system engineering approach. Preliminary steps include stakeholder identification, developing a broad scope and proposal, three build approaches, and then a concept of operations. Once this is done, the systems engineering process begins with functional requirements development and internal reviews. This step is followed by stakeholder, sponsor, and evaluation team reviews followed by STL data archive enhancement. Then comes the build design, documentation, review, and testing documents followed by the build development, testing, and deployment. The final step for each of the three builds defined in the preliminary steps isevaluation.
Source: ADMS Virginia Draft Final Report, December 1, 2004
Figure 2. Systems Engineering Approach used in ADMS Virginia Development

1.1.3 Operations Centers

1.1.3.1 NoVA District of VDOT

The Northern Virginia Smart Traffic Center is a high-tech communications hub situated in Arlington near the Pentagon. Controllers in this Traffic Center oversee more than 100 miles of roads. The system operates ramp meters, dynamic message signs (DMSs), highway advisory radio (HAR), and supports incident management activities.

Photograph of a Traffic Management Center operations room, including computer workstations and large wall monitors.

The Center also monitors the usage of HOV lanes. Gates and gate groups are used to reverse HOV lanes to accommodate the traffic flow heading north and east in the morning and south and west in the afternoon.

Loop detectors and pavement sensors that are embedded in the roadways prompt an automatic incident detection system that alerts Traffic Center controllers when and where there is likely to have been an incident. This equipment also gathers speed volume and occupancy data.

The Northern Virginia Smart Traffic Center Operators equipment inventory includes:

1.1.3.2 Hampton Roads Smart Traffic Center

The Hampton Roads region, located in Southeast Virginia, presents numerous challenges to the ongoing evolution and maintenance of a safe and effective transportation system. The region consists of ten cities (Chesapeake, Franklin, Hampton, Newport News, Norfolk, Poquoson, Portsmouth, Suffolk, Virginia Beach, and Williamsburg) and six counties (Gloucester, Isle of Wight, James City, Southampton, Surry, and York), with a current population of over 1.5 million people - an increase of 40% in 27 years. Over 100,000 military personnel live and travel in Hampton Roads, serving the Army, Navy, Marines, Air Force and Coast Guard. The area is also a prime vacation destination. On any given summer day, tourists can increase the region's population by as many as 100,000 people, and 85% are traveling by motor vehicle. Along with major tourist attractions, the region has the best natural deepwater harbor on the U.S. East Coast. More than fifty international shipping lines and over 400 commercial freight carrier companies operate in Hampton Roads, resulting in high volumes of commercial freight traffic. Over 560 thousand tractor-trailers arrive and depart from the three international marine port terminals annually.

I-64 is the primary Interstate route in the region; its eastern terminus is located here. Several Interstate "spur routes" are also located in the area:

The region's limited number of waterway crossings, high population, increasing influx of tourists, waves of military personnel traveling to and from the numerous military bases, and high volume of freight movement cause traffic incidents and delays on a daily basis around Hampton Roads.

The Freeway Traffic Management System installed at the HRSTC originally consisted of an extensive computer controlled, fiber-optic based communications and control network installed along 19 miles of the area freeways (I-64, -264 and I-564), 38 closed circuit television cameras, over 60 dynamic message signs strategically positioned across the entire Hampton Roads region, Wide-Area Highway Advisory Radio System, and Freeway Incident Response Teams patrolling over 70 miles of interstate in the region.

Phase 2 expansion of the Traffic Management System (TMS) was completed in March 2004. Phase 2 adds 31 miles of coverage on the peninsula and southside interstate (I-64, I-264, and I- 564) with 80 additional cameras and other roadway detectors.

Phase 3 expansion is currently underway. When completed, the total inventory for the STC will be over 275 cameras covering 113 miles of Hampton Roads freeways including I-64 from Lightfoot to Bowers Hill, I- 264/I-64/I-664 interchange; I-264 from Bowers Hill to Park Avenue, Virginia Beach; I-664 from Bowers Hill interchange through the Monitor Merrimac Memorial Bridge Tunnel to I- 64 interchange, Hampton; and I-564 from Terminal Boulevard, Norfolk to Gate 3 and 3A Naval Base.

1.1.3.3 Smart Travel Lab at UVA

The Smart Travel Lab is a state-of-the-art facility that supports research and education in the rapidly emerging area of ITS. Using the latest information technologies and analysis and modeling techniques, researchers in the lab are developing prototype systems and applications that promise to improve the effectiveness of ITS. It is a joint effort between the Department of Civil Engineering at the University of Virginia and the Virginia Transportation Research Council. The Lab serves as the direct connection to transportation management systems operated by the VDOT. This connection provides researchers with direct access to real ITS data and systems. This direct access has allowed the lab to provide substantive contributions to VDOT's ITS initiative, known as the Smart Travel Program. The mission of the Smart Travel Lab is to:

The foundation of the laboratory is an OC-3 connection to the Commonwealth of Virginia's wide area network known as "Network Virginia." This connection is used to continuously transmit data and video from four Virginia Department of Transportation (VDOT) traffic control systems. These systems include:

1.3 Purpose of Evaluation

The primary purpose of the evaluation is to assess how well the ADMS Virginia project met its objectives, namely:

The next section of this report outlines specifics about the evaluation approach.

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