Decatur Electronics EZ Stat, Руководство пользователя

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3.8.4 Traffic Speed Survey (Any Graph)
• PRINT : Prints the “EZ Stat Traffic Speed Survey” window .
• COPY TO CLIPBOARD : Copy the “EZ Stat Traffic Speed Survey”
window to the clipboard . You can use this to copy over to a
graphics program or Microsoft Word or Excel .
3.8.5 Understanding the Charts (Any Graph)
In the top left hand corner of each chart is a summery of
what the chart is showing . The summery not only shows what
parameters have been set for the graph (Report Start Date,
Report End Date, etc .) but also reveals some of the results .
Most of these are self-explanatory and need no fruther
discussion . However, the one area that can sometimes be
confusing is what the percentiles mean . Using Figure 3 .8 .1 as
an example, the summery shows the 50th percentile at 33 mph
and the 85th percentile at 83 mph . What this means is that 50%
of the vehicles were going 33 mph or less and that 85% of the
vehicles were going 83 mph or less .
3.9 Data Collection
The EZ Stat™ reads vehicle speeds 5 times per second . When a
moving object is detected by the radar, the logger expects it to
be present for at least 4 seconds, then receive a zero speed . The
maximum speed is recorded with the timestamp in the memory of
the logger module .
NOTE: The EZ Stat™ will not create a record if another car is in range
of the radar before the first one passes beyond the antenna . When
traffic is heavy, there will be no gap (zero speed) in speed readings,
and the EZ Stat™ will see the whole cluster of cars as one event .