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Among the most promising and innovative concepts today for alleviating urban traffic congestion is the use of video imaging for vehicle detection, automatic surveillance, and advanced control strategies. Because of its conceptual appeal, research in this area was initiated in the mid 70's in the United States and abroad. A system for vehicle detection through video imaging was recently developed at the University of Minnesota and is being implemented on the 1-394 and l-35W freeways in Minneapolis, Minnesota for incident detection. The Minnesota system, called AUTOSCOPE (TM), emulates loop detectors, a large number of which can easily be placed within the field of the camera's view through interactive graphics. In recent tests its performance matched or exceeded that of loops in vehicle counting, speed measurements, and extraction of certain measures of effectiveness. Evaluation tests of the AUTOSCOPE (TM) were very encouraging, thus the system was installed at a traffic intersection to demonstrate the effectiveness of this new technology as a replacement for loop detectors.

A microscopic, stochastic model for intersection design and traffic flow analysis is presented in this report. A simulation program, INTERSIM, based on this modeling, is developed. The INTERSIM program can be used to evaluate alternative control schemes and geometric configurations. INTERIM can also assist in solving traffic operation and management problems, e.g., determining optimum signal phasing and timing of intersections via an iterative process. The most common situations encountered in practice are examined. These include: four-way and T-intersections with up to three lanes on each approach; stop sign control; signal control (fixed time or vehicle actuated) with various phasing schemes; detector placement and functions, multi-use lanes; protected and permissive left-turn movements; and right turns on red, among others. The proposed modeling applies to both over-saturated and under-saturated traffic conditions. INTERSIM is superior to the other intersection simulation programs due to its ease of operation and fast execution speed.

This report summarizes the final results of the current project to enhance the KRONOS program. The resulting version, V8.0, being operated under the MS-DOS environment, can handle two freeways merging/diverging with a common section with total length up to 20 miles and eight lanes wide. The input data preparation is performed interactively using pop-up menu screen with a mouse. For instance, the geometrics are entered by selecting the configuration of each segment from the available alternatives presented on the screen. The current version has a total of 26 available segment types, which can treat most of the freeways in the U.S. Further, a new incident simulation module that can handle up to six stages in terms of time-variant capacities is also added to the new version. Following definition of the geometrics of each segment, the entire freeway can be plotted for verification. The other input requirements include the arrival/departure demand pattern at the freeway boundaries and ramps in user specified time intervals (minimum 1 minute). The demand patterns are also plotted for verification and can be as complex as desired. The program allows employment of user-specified flow-density models which are entered interactively. The change to input already entered can be made at any stage during the data entry. Note: The phase I report is available at https://hdl.handle.net/11299/156893.