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    <title>Transport Research International Documentation (TRID)</title>
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    <copyright>Copyright © 2026. National Academy of Sciences. All rights reserved.</copyright>
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    <managingEditor>tris-trb@nas.edu (Bill McLeod)</managingEditor>
    <webMaster>tris-trb@nas.edu (Bill McLeod)</webMaster>
    <image>
      <title>Transport Research International Documentation (TRID)</title>
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      <link>https://trid.trb.org/</link>
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    <item>
      <title>A COMPUTER PROGRAM FOR RAMP CAPACITY</title>
      <link>https://trid.trb.org/View/117126</link>
      <description><![CDATA[THE INSTITUTE OF TRANSPORTATION AND TRAFFIC ENGINEERING, WITH PARTIAL SUPPORT FROM THE AUTOMOTIVE SAFETY FOUNDATION, IS DEVELOPING A SERIES OF COMPUTER PROGRAMS FOR CAPACITY ANALYSIS IN ACCORDANCE WITH THE 1965 HIGHWAY CAPACITY MANUAL. THIS PAPER DESCRIBES THE PROGRAM DEALING WITH RAMP CAPACITY. THE COMPUTER PROGRAM IS WRITTEN IN THE FORTRAN LANGUAGE AND WILL SOLVE FOR EITHER RAMP SERVICE VOLUME OR LEVEL OF SERVICE FOR AN INDIVIDUAL SINGLE-LANE RAMP. THE COMPUTATIONAL PROCEDURE IS BASED ON THAT GIVEN IN THE 1965 HIGHWAY CAPACITY MANUAL (HCM). THE PAPER INCLUDES A DETAILED DISCUSSION OF THE IMPUT DATA, THE CHECKS ON THE INPUT DATA AND THE COMPUTED RESULTS, A FLOW DIAGRAM, AND A LISTING OF THE COMPUTER OUTPUT FOR A SPECIFIC EXAMPLE. THE PROCEDURE USED IN THE PROGRAM IS DISCUSSED VERY BRIEFLY AND A COMPARISON IS MADE BETWEEN THE MANUAL AND COMPUTER PROGRAM RESULTS FOR SEVERAL EXAMPLE PROBLEMS. /BPR/]]></description>
      <pubDate>Fri, 13 Aug 2004 18:56:20 GMT</pubDate>
      <guid>https://trid.trb.org/View/117126</guid>
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    <item>
      <title>A DIGITAL SIMULATION PROGRAM OF A SECTION OF FREEWAY WITH ENTRANCE AND EXIT RAMPS</title>
      <link>https://trid.trb.org/View/117103</link>
      <description><![CDATA[A COMPUTER PROGRAM DEVELOPED FOR THE SIMULATION OF A SECTION OF FREEWAY, INCLUDING SEVERAL EXIT AND ENTRANCE RAMPS IS DESCRIBED. THE PROGRAM ALLOWS FOR THE SIMULATION OF THE TRAFFIC OPERATION UNDER DIFFERENT MODES OF ENTRANCE RAMP CONTROL: FIXED-RATE METERING, DEMAND-CAPACITY METERING, GAP- ACCEPTANCE CONTROL AND, OF COURSE, NO CONTROL. THE COMPUTER LOGIC AND SIMULATION TECHNIQUE ARE DISCUSSED IN DETAIL. LIMITED OUTPUT OF THE PROGRAM IS PRESENTED AS EVIDENCE OF THE FEASIBILITY AND REALISM OF THE SIMULATION MODEL. /AUTHOR/]]></description>
      <pubDate>Fri, 13 Aug 2004 18:56:15 GMT</pubDate>
      <guid>https://trid.trb.org/View/117103</guid>
    </item>
    <item>
      <title>OPTIMIZATION OF SINGLE-LANE FREEWAY TRAFFIC FLOW BY SELECTIVE RAMP CLOSURE</title>
      <link>https://trid.trb.org/View/117056</link>
      <description><![CDATA[THE DIGITAL COMPUTER IS USED TO SIMULATE FREEWAY TRAFFIC FLOW AND THE EFFECT ON THIS FLOW OF THE INGRESS AND EGRESS OF TRAFFIC FROM THE FREEWAY RAMPS. IT WAS OBSERVED THAT SELECTIVE RAMP CLOSURE ON SINGLE-LANE FREEWAY TRAFFIC FLOW PROVIDES AN EFFECTIVE MEANS FOR ESTABLISHING A MINIMUM FREEWAY VELOCITY AND THUS MAXIMIZES TRAFFIC FLOW. /BPR/]]></description>
      <pubDate>Fri, 13 Aug 2004 18:56:04 GMT</pubDate>
      <guid>https://trid.trb.org/View/117056</guid>
    </item>
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      <title>SOME MATHEMATICAL ASPECTS OF THE PROBLEM OF MERGING</title>
      <link>https://trid.trb.org/View/117045</link>
      <description><![CDATA[AS ROADS AND HIGHWAYS BECOME CAPABLE OF CARRYING HIGHER TRAFFIC VOLUMES, THE PERTURBATIONS INTRODUCED BY VEHICLES TRAVELING AT SPEEDS OR IN PATHS THAT DIFFER FROM THE NORM BECOME INCREASINGLY HARMFUL TO SAFE AND EFFICIENT OPERATION OF THE ROAD NETWORK. SOME OF THIS INDIVIDUAL VARIATION CAN BE REMOVED, OR DIMINISHED, BY SENSIBLE EFFORTS TO EDUCATE AND CONTROL DRIVERS. THE NECESSITY REMAINS FOR ACCELERATING, DECELERATING, WEAVING, AND MERGING. PERHAPS THE MOST IMPORTANT EXAMPLE OF SUCH A SITUATION IS THE FREEWAY ON-RAMP AND ACCELERATION LANE. AT THESE POINTS, WHICH MUST BE PROVIDED FAIRLY FREQUENTLY IN URBAN AREAS, THE SMOOTH FLOW OF TRAFFIC IS PERPETUALLY HARASSED BY NEW ARRIVALS. LOCATION AND DESIGN OF ON-RAMPS AND ACCELERATION LANES ARE CLOSELY CONNECTED WITH THE INFLUENCE THEY EXERT ON TRAFFIC STABILITY. A COMPLETE MATHEMATICAL MODEL FOR MERGING CANNOT BE CLAIMED, BUT IT IS HOPED INSTEAD TO POINT OUT THE PROBLEMS IN FORMULATION OF SUCH A MODEL, AND SOLVE A FEW OF THEM. THE MERGING PROBLEM HAS SOME INTEREST BEYOND THE SIMPLE QUESTION OF WAITING FOR A SUITABLE GAP IN TRAFFIC. FOR EXAMPLE, A CAR TRAVELING ALONG AN ACCELERATION LANE WHILE WAITING FOR THE OPPORTUNITY TO MERGE IS MATHEMATICALLY EQUIVALENT TO A CAR WAITING AT A STOP SIGN, OR THE DIFFERENCE RESIDES ONLY IN THE MOVING COORDINATE SYSTEM. HOWEVER, THE DRIVER ON THE ACCELERATION LANE IS ABLE TO CONTROL THE TRAFFIC STREAM WITH WHICH HE WISHES TO MERGE BY CHANGING HIS OWN SPEED, THEREBY INCREASING OR DECREASING HIS HEADWAY AND SPACING RELATIVE TO THE MAIN STREAM. THE STOP SIGN PROBLEM DOES NOT CONTAIN THIS IMPORTANT INGREDIENT, AND THEREFORE QUESTIONS OF DRIVING POLICY DO NOT ARISE. THERE IS ONLY ONE POSSIBLE POLICY AT A STOP SIGN: WAIT FOR A SUITABLE GAP. THEREFORE, A MATHEMATICAL MODEL FOR A STOP SIGN IS PURELY DESCRIPTIVE AND ITS PRINCIPAL RESULT CONSISTS OF A PROBABILITY DISTRIBUTION FOR DELAY. THERE IS A MUCH MORE VARIED AND INTERESTING COLLECTION OF PROBLEMS AVAILABLE WHEN THE DRIVER IS ALLOWED TO ALTER (WITHIN LIMITS) HIS ATTITUDE WITH RESPECT TO THE MAIN STREAM. /AUTHOR/]]></description>
      <pubDate>Fri, 13 Aug 2004 18:56:02 GMT</pubDate>
      <guid>https://trid.trb.org/View/117045</guid>
    </item>
    <item>
      <title>GAP ACCEPTANCE CHARACTERISTICS FOR RAMP-FREEWAY SURVEILLANCE AND CONTROL AND DISCUSSION</title>
      <link>https://trid.trb.org/View/117039</link>
      <description><![CDATA[GAP ACCEPTANCE CHARACTERISTICS AND MERGING DELAY CHARACTERISTICS WERE DETERMINED ON 6 INBOUND ENTRANCE RAMPS OF THE GULF FREEWAY. MERGING VEHICLES WERE DIVIDED INTO 2 GROUPS' THOSE IN WHICH THE DRIVER REJECTED GAPS BEFORE FINALLY ACCEPTING A GAP AND THOSE IN WHICH THE DRIVER OF A RAMP VEHICLE ACCEPTED THE FIRST GAP. THE FORMER WAS REFERRED TO AS STOPPED VEHICLES AND THE LATTER AS MOVING VEHICLES. THE CRITICAL GAP FOR STOPPED VEHICLES WAS FOUND TO BE ABOUT 20 PERCENT HIGHER THAN FOR MOVING VEHICLES. IT WAS CONCLUDED THAT THE CRITICAL GAP /MEDIAN/ FOR THE MERGING MANEUVER FROM AN ENTRANCE RAMP IS INDEPENDENT OF THE FREEWAY VOLUME BUT IS APPARENTLY AFFECTED BY RAMP GEOMETRICS AND RAMP CONTROLS. A DISTRIBUTION OF CRITICAL GAPS WAS FORMED AND FITTED TO A GAMMA DISTRIBUTION. MERGING DELAY VALUES CALCULATED USING THIS DISTRIBUTION WERE SHOWN TO BE HIGHER THAN THOSE CALCULATED ASSUMING THAT ALL DRIVERS HAVE THE SAME FIXED CRITICAL GAP. IF THE DISTRIBUTION TIME SPENT BY THE MERGING VEHICLE AT THE HEAD OF THE QUEUE IS APPROXIMATED BY A GAMMA DISTRIBUTION, THE ENTRANCE RAMP MERGING OPERATION MAY BE CONSIDERED WITHIN THE CONTEXT OF CLASSICAL QUEUING THEORY. BASED ON THIS QUEUING MODEL, A RAMP METERING TECHNIQUE WAS DEVELOPED, WHICH TAKES INTO ACCOUNT THE INDIVIDUALITY OF ENTRANCE RAMPS. IT IS SHOWN THAT THE NEED EXISTS FOR AN AUTOMATIC RAMP CONTROL TECHNIQUE COMBINING THE MICROSCOPIC APPROACH DEVELOPED IN THIS PAPER WITH THE SYSTEMS OR MACROSCOPIC APPROACH WHICH HAS BEEN USED AS THE BASIS FOR THE PAST MANUAL RAMP METERING EXPERIMENTS ON THE GULF FREEWAY.]]></description>
      <pubDate>Fri, 13 Aug 2004 18:56:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/117039</guid>
    </item>
    <item>
      <title>INTERDEPENDENCE OF CERTAIN OPERATIONAL CHARACTERISTICS WITHIN A MOVING TRAFFIC STREAM</title>
      <link>https://trid.trb.org/View/117031</link>
      <description><![CDATA[THE CONGRESS STREET EXPRESSWAY SURVEILLANCE PROJECT INVESTIGATED THE INTERDEPENDENCE OF CERTAIN FREEWAY OPERATIONAL CHARACTERISTICS WITHIN A MOVING TRAFFIC STREAM BY MEANS OF ELECTRONIC TRAFFIC SURVEILLANCE EQUIPMENT. LANE OCCUPANCY, WHICH IS A POINT MEASUREMENT COMPARABLE WITH CONCENTRATION, WAS COMPARED TO VOLUME AND SPEED, AND THE INTERRELATIONSHIP WAS RECORDED. LANE OCCUPANCY WAS USED TO PREDICT VEHICLE SPEEDS WITH REASONABLE ACCURACY. AERIAL PHOTOGRAPHS WERE USED TO COMPARE OCCUPANCY AND AERIAL DENSITY OF TRAFFIC. THE COMPARISON EMPHASIZED THE CONTRAST BETWEEN POINT MEASUREMENTS AND SECTION MEASUREMENTS. TRAFFIC CONGESTION WAS DISCUSSED AND A POSSIBLE DEFINITION OF CONGESTION WAS DEVELOPED. SPEED INVERSION WAS DESCRIBED. THE VALUE OF VARIOUS MEASURES OF TRAFFIC PERFORMANCE INCLUDING VOLUME, SPEED, SPEED DIFFERENCES, HEADWAYS AND OF VARIATIONS IN INDIVIDUAL SPEEDS, SPEED DIFFERENCES AND HEADWAYS FOR PREDICTING THE ADVENT OF CONGESTION WAS CONSIDERED. THE POSSIBLE REQUIREMENTS OF A TRAFFIC CONTROL SYSTEM /SUCH AS RAMP METERING/ TO CONTROL CONGESTION WERE STUDIED.]]></description>
      <pubDate>Fri, 13 Aug 2004 18:55:58 GMT</pubDate>
      <guid>https://trid.trb.org/View/117031</guid>
    </item>
    <item>
      <title>GAP AVAILABILITY STUDIES</title>
      <link>https://trid.trb.org/View/117030</link>
      <description><![CDATA[GAP AVAILABILITY STUDIES WERE CONDUCTED TO ESTIMATE METERING RATES WHICH MIGHT BE USED IN THE AUTOMATIC RAMP METERING PROGRAM OF THE CHICAGO EXPRESSWAY SURVEILLANCE PROJECT. GAP AVAILABILITY /TIME HEADWAY/ DISTRIBUTIONS WERE COMBINED WITH GAP ACCEPTABILITY DISTRIBUTIONS FOR VARIOUS VOLUME AND LANE OCCUPANCY LEVELS TO ESTIMATE THE NUMBER OF ACCEPTABLE GAPS AVAILABLE UNDER DIFFERENT VOLUME AND LANE OCCUPANCY LEVELS. UNEXPECTEDLY, AN INCREASING NUMBER OF ACCEPTABLE AVAILABLE GAPS WAS FOUND AS THE SHOULDER LANE VOLUME AND OCCUPANCY LEVEL INCREASED. SIGNIFICANT DIFFERENCES WERE FOUND IN THE MEASURED TIME HEADWAY DISTRIBUTIONS BETWEEN LOCATIONS. THERE WAS A SIGNIFICANT DIFFERENCE BETWEEN EACH MEASURED TIME HEADWAY DISTRIBUTION AND THE POISSON DISTRIBUTION. THE POISSON DISTRIBUTION DOES NOT APPEAR TO SATISFACTORILY DESCRIBE TIME HEADWAY DISTRIBUTIONS FOR THE LOCATIONS AND TRAFFIC CONDITIONS STUDIED. THE ANALYSIS OF THE CUMULATIVE FREQUENCIES INDICATED THAT AS VOLUME LEVEL INCREASES, THE TIME HEADWAY BECOMES MORE UNIFORM. IT IS RECOMMENDED THAT A COMPREHENSIVE GAP ACCEPTANCE STUDY BE UNDERTAKEN, AND SUGGESTIONS TO BE CONSIDERED IN DESIGNING SUCH A STUDY ARE INCLUDED IN THE REPORT.]]></description>
      <pubDate>Fri, 13 Aug 2004 18:55:58 GMT</pubDate>
      <guid>https://trid.trb.org/View/117030</guid>
    </item>
    <item>
      <title>STATEMENTS OF NEEDED RESEARCH IN CAPACITY AND FREEWAY OPERATIONS</title>
      <link>https://trid.trb.org/View/113627</link>
      <description><![CDATA[CONTENTS: CAPACITY RESEARCH NEEDS TRAFFIC CHARACTERISTICS CAPACITY AND LEVEL OF SERVICE FACTORS AFFECTING CAPACITY AND SERVICE VOLUMES AT GRADE INTERSECTIONS WEAVING RAMPS FREEWAYS HIGHWAYS WITHOUT ACCESS CONTROL BUS TRANSIT OTHER FREEWAY OPERATIONS RESEARCH PROBLEM STATEMENTS DESIGN AN ELECTRONIC INFORMATION AND CONTROL SYSTEM FOR SELECTION OF AN OPTIMUM ROUTE FROM TWO OR MORE ALTERNATE ROUTES IMPROVED OPERATION OF FREEWAY-TO-FREEWAY INTERCHANGES THE EFFECT OF ADVERSE WEATHER ON FREEWAY OPERATIONS OPERATIONAL RELATIONSHIPS BETWEEN FREEWAY AND SURFACE STREET SYSTEMS DESIGN OF A MULTIPURPOSE VEHICLE FOR FREEWAY PATROL CHARACTERISTICS OF THE STRANDED MOTORIST DETECTION OF STOPPED VEHICLES ON FREEWAYS DEVELOPMENT OF HUMAN FACTORS CRITERIA TO BE USED IN THE DESIGN AND EVALUATION OF VARIABLE-MESSAGE SIGNS FREEWAY DRIVER EDUCATION LIST OF COMMITTEE MEMBERS.]]></description>
      <pubDate>Fri, 13 Aug 2004 18:07:57 GMT</pubDate>
      <guid>https://trid.trb.org/View/113627</guid>
    </item>
    <item>
      <title>FREEWAY OPTIMIZATION UTILIZING RAMP METERING - AN IVHS TOOL</title>
      <link>https://trid.trb.org/View/457644</link>
      <description><![CDATA[This paper presents a discussion of a computer optimization program, which is used to optimize ramp metering and freeway flow by timing ramp signals to prevent excessive queuing on ramps while simultaneously minimizing delay on the freeway. The program can be used to design for a specified level of service and/or ramp queuing capacities based on the users constraints. This computer program was calibrated based on a specific section of the Milwaukee County Interstate Highway (IH) 94 freeway system. Data inputs to the program include freeway volumes, ramp volumes, distances between ramps, and ramp queuing capacities. The optimization program is a spreadsheet template so additional ramps can be easily added. Guidelines for application and further calibration with IVHS systems are discussed.]]></description>
      <pubDate>Thu, 31 Jan 2002 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/457644</guid>
    </item>
    <item>
      <title>EVALUATION OF TWO TOLLING STRATEGIES FOR HIGHWAY 407 IN TORONTO</title>
      <link>https://trid.trb.org/View/542000</link>
      <description><![CDATA[Two tolling strategies were recently suggested for Highway 407 in the Greater Toronto Area (GTA).  The GTA is one of the fastest growing urban areas in North America with a population of about 5 million.  Highway 407, a six-/four-lane freeway, has been considered for many years as a relief for Highway 401 - the busiest highway in North America, used by more than a million vehicles per day.  Highway 407 is being planned and constructed as a toll highway.  The first strategy investigated is to encourage long distance travelers to use Highway 407 by reducing the toll rate from CD$0.075/km to $0.06/km after the first 10 km.  This is modeled by using multiclass trip assignment with generalized cost.  Aside from the class of drivers who are not going to use the highway for various personal reasons, there are two main classes of drivers - namely, drivers who travel 10 km or more, and those who travel less than 10 km.  The second strategy investigated is to put extra tolls on Highway 407 ramps connecting the highway with widened Highways 427, 400, and 404. The purpose of the second strategy is to recover the cost of widening these highways near Highway 407 through ramp toll revenues.  The GTA mathematical model, within the EMME/2 environment, and the evaluation process used are described. Evaluation results are discussed.]]></description>
      <pubDate>Wed, 16 Dec 1998 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/542000</guid>
    </item>
    <item>
      <title>PREDICTION MODELS FOR TRUCK ACCIDENTS AT FREEWAY RAMPS IN WASHINGTON STATE USING REGRESSION AND ARTIFICIAL INTELLIGENCE TECHNIQUES</title>
      <link>https://trid.trb.org/View/540850</link>
      <description><![CDATA[Three different modeling approaches were applied to explain truck accidents at interchanges in Washington State during a 27-month period.  Three models were developed for each ramp type including linear regression, neural networks, and a hybrid system using fuzzy logic and neural networks.  The study showed that linear regression was able to predict accident frequencies that fell within one standard deviation from the overall mean of the dependent variable.  However, the coefficient of determination was very low in all cases.  The other two artificial intelligence (AI) approaches showed a high level of performance in identifying different patterns of accidents in the training data and presented a better fit when compared to the regression model.  However, the ability of these AI models to predict test data that were not included in the training process showed unsatisfactory results.]]></description>
      <pubDate>Mon, 09 Nov 1998 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/540850</guid>
    </item>
    <item>
      <title>METERED LIGHTS: A CURSE OR A BLESSING</title>
      <link>https://trid.trb.org/View/541109</link>
      <description><![CDATA[The blinking red lights that line more and more freeway on-ramps are metering lights.  With the possible exception of carpool lanes, nothing since the invention of the freeway has had a greater impact on the way we drive.  To savvy motorists, these lights are a life preserver, preventing huge platoons of cars from flowing onto highways and bringing the commute to a crawl. To motorists idling for 10 minutes on city streets waiting for their turn to get on the freeway, they are a subject of scorn. It has been shown, however, that they do shave significant time off total travel time when operating properly.]]></description>
      <pubDate>Wed, 04 Nov 1998 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/541109</guid>
    </item>
    <item>
      <title>A MACROSCOPIC SIMULATION TOOL FOR EVALUATION OF HOV LANE AND RAMP METERING OPERATIONS IN FREEWAY NETWORKS</title>
      <link>https://trid.trb.org/View/487059</link>
      <description><![CDATA[A macroscopic simulation tool was developed to evaluate the traffic operations of the High Occupancy Vehicle (HOV) lanes in a freeway network.  The continuum modeling approach employed in this research divides a given freeway section into 100-ft (30-m) increments and estimates the macroscopic traffic parameters, such as flow, speed, and density every second by using the numerical scheme specifically designed to solve time-dependent, compressible flows containing strong shocks.  Using the built-in graphical user interface, the user can build a given freeway section on the computer screen using a mouse.  The output information can be analyzed with the graphic functions or stored in a spreadsheet file format that can be imported by common spreadsheet software.]]></description>
      <pubDate>Fri, 26 Jun 1998 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/487059</guid>
    </item>
    <item>
      <title>MODELING DRIVER BEHAVIOR DURING MERGE MANEUVERS</title>
      <link>https://trid.trb.org/View/472651</link>
      <description><![CDATA[The major objective of this study is to develop empirical methodologies for modeling ramp driver acceleration-deceleration and gap acceptance behavior during freeway merge maneuvers.  A large quantity of freeway merge data were collected from several entrance ramps including both parallel and taper type acceleration lanes capturing a wide traffic flow range to suit different analysis purposes.  Comprehensive freeway merge traffic analyses were conducted using the collected data.  Both graphical presentations and independence tests in contingency tables indicated that ramp vehicle merge behavior is insignificantly related to any single traffic parameter, such as ramp vehicle approach speeds, freeway flow levels, and speed differentials as well as time or distance gaps between ramp vehicles and surrounding freeway and ramp vehicles.  Combination forms of these traffic parameters were found to be better indicators for modeling freeway merge driver behavior.  Initially, ramp vehicle acceleration-deceleration behavior models were conceptually formulated as extended forms of conventional nonlinear car-following models incorporating joint freeway and ramp vehicle effects.  These sophisticated nonlinear specifications, although theoretically attractive, have been proven to be infeasible to predict dynamic ramp vehicle acceleration-deceleration rates.  A multinomial probit model, using speed differentials, distance separations of ramp vehicles to corresponding freeway and ramp vehicles, distance to the acceleration lane terminus, and Markov indexes as attributes, predicted ramp driver acceleration, deceleration, or constant speed choice behavior.  The resulting acceleration or deceleration rate magnitudes were predicted by a family of exponential curves using ramp vehicle speed as an explanatory variable.  Calibration results of a binary logit gap acceptance function indicated that perceived ramp driver angular velocity to a corresponding freeway lag vehicle and remaining distance to the acceleration lane end are the best gap acceptance decision criteria.]]></description>
      <pubDate>Fri, 06 Feb 1998 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/472651</guid>
    </item>
    <item>
      <title>FREEWAY RAMP METERING USING ARTIFICIAL NEURAL NETWORKS</title>
      <link>https://trid.trb.org/View/475341</link>
      <description><![CDATA[This paper proposes a nonlinear approach for designing local traffic-responsive ramp controls using artificial neural networks. The problem is formulated as a nonlinear feedback control problem, where the system model is the well known hydrodynamic model developed by Lighthill and Whitham (1955), and Richards (1956), the model's flow-density relationship is nonlinear, and the feedback nonlinear controllers are composed of one or a number of feed-forward neural networks. These neural network controllers are of integral (I) or proportional-plus-integral) PI type, and can be tuned on-line to achieve prescribed performance. Initial simulation results show that such an approach is promising.]]></description>
      <pubDate>Mon, 26 Jan 1998 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/475341</guid>
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