Tutorial Average Speed

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Space-Mean Speed Space-Mean Speed is the average speed of all vehicles occupying a given section of roadway over a specified time (essentially, the inverse of travel time for all vehicles over the specified section length).

The steps to verify Space-Mean Speed are as follow: Step 1. Run the Simulation Step 2. Verify the Link Data Calculations ''Note that the average speed may differ by <1% and still be correct. This is due to truncation of decimals in the excel files.''
 * 1) Open SwashSim.
 * 2) Open the project file and the network file.
 * 3) Open the simulation control panel and set the desired warm-up time, simulation duration, and number of replications
 * 4) Ensure that the link performance measure data and vehicle time step data option boxes are checked.
 * 5) Click the Run Simulation button. The CSV output files will be saved in the same folder as the SSIM file you are working in.
 * 1) Open the desired time step data file (ex. TSD_1_0_1.csv).
 * 2) Select all columns and rows and format as table.
 * 3) Create a new column and enter the formula =IF(H2=H1,"","Change") and click on the header arrow in row 1 of this new column and uncheck the box (Blanks).
 * 4) In the Link ID column uncheck all except for the link of interest.
 * 5) Copy values from column A (SimTime) onto a new sheet and label this column "Entry time".
 * 6) In the Link ID column uncheck the link of interest and check the link immediately following the link of interest (the reason for this is the times shown are only the ENTRY times, so we will need the link entry time for both the link of interest as well as the link entry time for the following link).
 * 7) Copy values from column A (SimTime) onto the the sheet you just created in an adjacent column to the data you just pasted and label this column "Exit Time".
 * 8) Subtract the exit time from the entry time to calculate the time spent on link for each vehicle.
 * 9) Average all of the time spent on link values you just calculated to find the average time spent on link.
 * 10) Go back to SwashSim and right click on the link of interest. Click "Edit Link" and note the link length shown (in feet).
 * 11) Divide the link length by the average time spent on link to find the average speed (in feet per second). Multiply this value by 0.68181818 to determine the average speed in miles per hour.
 * 12) Open the link results file (ex. LinkResults.csv).
 * 13) Ensure that the previously calculated average speed matches the average speed shown in column F of the link results file.

Time-Mean Speed Time-Mean Speed is the average speed of all vehicles passing a point on a roadway over a specified time (instantaneous point speed, as taken by a radar gun or other detector).

The steps to verify Time-Mean Speed are as follow: Step 1. Run the Simulation Step 2. Verify the Link Data Calculations ''Note that the average speed may differ by <1% and still be correct. This is due to truncation of decimals in the excel files.''
 * 1) Open SwashSim.
 * 2) Open the project file and the network file.
 * 3) Open the simulation control panel and set the desired warm-up time, simulation duration, and number of replications
 * 4) Ensure that the detector aggregate measures data and detector vehicle actuation data output option boxes are checked.
 * 5) Click the Run Simulation button. The CSV output files will be saved in the same folder as the SSIM file you are working in.
 * 1) Open the detector file for the desired link and lane (ex. Link_12_Lane_2_Detector_2_1_1.csv).
 * 2) Calculate an average of all speeds in column J.
 * 3) Open the detector aggregate measures file (ex. DetectorAggregateMeasures_MediumFreeway.csv).
 * 4) Ensure that the previously calculated average speed matches the average speed shown in column I of the detector aggregate measures file.