Skip to content

MeasurementSpecificCharacteristics

The measurementSpecificCharacteristics element appears one or more times per measurement location and describes a measurement-point-data-type-vehicle-category trio.

The structure of the element is shown below:

image

Explanation of Structure

The content of this element is further described using the specific example "3 measurement points, 1 measurement location" from the image below:

image

The three measurement points in this scenario each provide both intensity and speed data. The two leftmost lanes do this without vehicle categorization, while the far-right lane provides data for 3 vehicle categories. For this measurement location, this results in 12 measurementSpecificCharacteristics elements.

For this measurement location, this results in a total of 12 measurementSpecificCharacteristics elements. The order of the indexed measurementSpecificCharacteristics is prescribed:

  1. First – if available and applicable – by lane (specificLane);
  2. Then by measurement type (specificMeasurementValueType);
  3. Finally, by vehicle category (specificVehicleCharacteristics) in sorted order.

Sorting follows normal alphanumeric rules, with anyVehicle listed last per measurement-point-data-type combination. For the above example, this results in the following:

Index laneNumber specificMeasurementValueType vehicleCategory
0 1 trafficFlow anyVehicle
1 1 trafficSpeed anyVehicle
2 2 trafficFlow anyVehicle
3 2 trafficSpeed anyVehicle
4 3 trafficFlow < 5.6
5 3 trafficFlow >= 5.6, <= 12.2
6 3 trafficFlow >= 12.2
7 3 trafficFlow anyVehicle
8 3 trafficSpeed < 5.6
9 3 trafficSpeed >= 5.6, <= 12.2
10 3 trafficSpeed >= 12.2
11 3 trafficSpeed anyVehicle

The measurementSpecificCharacteristics element has one mandatory attribute, and several elements which are described below.

Attributes

Attribute Type Required Domain Description
index Integer Yes >=0 Sequence number of the characteristics, as described above

Elements

Element Type Required Domain Description
accuracy Percentage Yes >=0, <=100 Default accuracy of the respective measurement point in percentage
computationMethod ComputationMethodEnum Yes See explanation The element computationMethod describes the method used for calculating the values provided for this measurement location
measurementSide DirectionEnum No anticlockwise, clockwise, northBound, northEastBound, eastBound, southEastBound, southBound, southWestBound, westBound, northWestBound Describes the side of the road on which the measurement is taken. This can help with location identification, particularly on surrounding road networks
period Seconds Yes >0 Duration of the measurement period in seconds
specificMeasurementValueType MeasuredOrDerivedDataTypeEnum Yes See explanation This element is used to indicate the type of measurement
specificVehicleCharacteristics VehicleCharacteristics Yes N/A The specificVehicleCharacteristics element describes the vehicles the measurement value pertains to
specificLane Lane No allLanesCompleteCarriageway, busLane, centralReservation, hardShoulder, lane1, lane2, lane3, lane4, lane5, lane6, lane7, lane8, lane9, rushHourLane, tidalFlowLane Used to specify the respective lane or carriageway

Explanation of specificVehicleCharacteristics

For each measurement location, the category 'anyVehicle' is indicated at least once per measurement point using the vehicleType element. In other specificVehicleCharacteristics elements for that measurement point, only lengthCharacteristic may be used. This element may appear once or twice to describe the lower and/or upper bounds of the category (expressed in length).

Sub-element computationMethod

The computationMethod element describes the method used to calculate the values for this measurement location. The following possible values are available:

  • arithmeticAverageOfSamplesBasedOnAFixedNumberOfSamples: Arithmetic average over a fixed number of values, i.e., A = (v1 + v2 + … + vn) / n, with n fixed;
  • arithmeticAverageOfSamplesInATimePeriod: Arithmetic average over values in a fixed time period, i.e., A = (v1 + v2 + … + vn) / n, with n variable;
  • harmonicAverageOfSamplesInATimePeriod: Harmonic average over values in a fixed time period, i.e., H = n / (1/v1 + 1/v2 + … + 1/vn), with n variable;
  • medianOfSamplesInATimePeriod: Median of values in a fixed period, meaning half of the values in that period are smaller or equal to the median M;
  • movingAverageOfSamples: Moving average over values, i.e., At=1 = ((n-1) * (At=0/n) + vn)/n, with n fixed.

Sub-element specificMeasurementValueType

This element is used to indicate the type of measurement. The following possible values are available:

  • trafficSpeed: For speed measurements
  • trafficFlow: For intensity measurements
  • travelTimeInformation: For travel time measurements
  • trafficStatusInformation: For queue measurements
XML Example 
<measurementSpecificCharacteristics index="0">
    <measurementSpecificCharacteristics>
        <accuracy>95</accuracy>
        <computationMethod>arithmeticAverageOfSamplesInATimePeriod</computationMethod>
        <measurementSide>southWestBound</measurementSide>
        <period>60</period>
        <specificMeasurementValueType>trafficFlow</specificMeasurementValueType>
        <specificVehicleCharacteristics>
            <com:vehicleType>anyVehicle</com:vehicleType>
        </specificVehicleCharacteristics>
        <specificLane>
            <loc:laneNumber>1</loc:laneNumber>
        </specificLane>
    </measurementSpecificCharacteristics>
</measurementSpecificCharacteristics>
...
<measurementSpecificCharacteristics index="4">
    <measurementSpecificCharacteristics>
        <accuracy>95</accuracy>
        <computationMethod>arithmeticAverageOfSamplesInATimePeriod</computationMethod>
        <measurementSide>southWestBound</measurementSide>
        <period>60</period>
        <specificMeasurementValueType>trafficFlow</specificMeasurementValueType>
        <specificVehicleCharacteristics>
            <com:lengthCharacteristic>
                <com:comparisonOperator>lessThan</com:comparisonOperator>
                <com:vehicleLength>5.6</com:vehicleLength>
            </com:lengthCharacteristic>
        </specificVehicleCharacteristics>
        <specificLane>
            <loc:laneNumber>3</loc:laneNumber>
        </specificLane>
    </measurementSpecificCharacteristics>
</measurementSpecificCharacteristics>
Go back to the previous page