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From page 85... ... Guide to Truck Activity Data for Emissions Modeling D-1 Appendix D Case Study #4: Truck Extended Idling and Starts from Fleet Telematics Data D.1 Emissions Model Inputs Supported • Truck hotelling (distribution of extended idling by hour and duration) Read the entire page →
From page 86... ... Guide to Truck Activity Data for Emissions Modeling D-2 During a hotelling period, the truck may be in one of the four modes: 1) extended idling of the main engine, 2) Read the entire page →
From page 87... ... Guide to Truck Activity Data for Emissions Modeling D-3 D.4 Data Sources Table D.1 Data Sources Data Source Source Agency/ Organization Availability and Cost Truck fleet telematics data (GPS and ECU) Vnomics Purchased for 300 trucks for one month Truck stop locations Truck Stops Plus Purchased in 2014 for $40, http://www.truckstopinfoplus.com/ Truck/RV fuel stations POI Factory Free, http://www.poi-factory.com/node/26860 The truck fleet telematics data were acquired from Vnomics for 300 trucks that performed long-haul operation and were likely to engage in hotelling activities due to the Hours-of-Service rule (FMCSA, 2017) Read the entire page →
From page 88... ... Guide to Truck Activity Data for Emissions Modeling D-4 Figure D.1 Geographic Coverage of the Data for 300 Trucks Acquired in This Study Background image: GoogleEarth. Figure D.2 Geographic Coverage of the Data for One Truck Spanning Multiple Counties and States Background image: GoogleEarth. Read the entire page →
From page 89... ... Guide to Truck Activity Data for Emissions Modeling D-5 In addition to the fleet telematics data, data on truck stop locations were acquired from databases available for free or at nominal cost. The Truck Stops Plus dataset was purchased for a different project in 2014 (Perez and Koupal, 2014) Read the entire page →
From page 90... ... Guide to Truck Activity Data for Emissions Modeling D-6 data includes both vehicle speed and engine speed, "engine-on" and "engine-off" events can also be identified and used to represent the start and the end of a trip. In other words, a "trip" in the context of this case study is the entire period of engine operation from the engine-on event to the engine-off event as shown in 3. Read the entire page →
From page 91... ... Guide to Truck Activity Data for Emissions Modeling D-7 Table D.4 Definition of Truck Activities Activity Definition Vehicle trip 1 -- > 6 Vehicle parked 6 -- > 1 Vehicle moving 3 -- > 4 Vehicle stopping 4 -- > 3 Hotelling x hrs < vehicle stopping < y hrs Engine trip 2 -- > 5 Engine idling 2 -- > 3 & 4 -- > 5 & 2 -- > 5 Engine soaked 5 -- > 2 Figure D.3 Illustration of Key-on versus Engine-on Event Figure D.4 Long-Duration Idling (>12 hrs) at a Truck Stop Facility Image courtesy GoogleEarth. Read the entire page →
From page 92... ... Guide to Truck Activity Data for Emissions Modeling D-8 Figure D.5 Long-Duration Idling (>12 hrs) at a Warehousing Facility Image courtesy GoogleEarth. Read the entire page →
From page 93... ... Guide to Truck Activity Data for Emissions Modeling D-9 Figure D.7 159 Extended Idling Events of At Least 8 Hours Sources: Analysis of Vnomics data by UC-Riverside; image background courtesy GoogleEarth. Figure D.8 Truck Stop Facilities Sources: Truck Stops Plus (2014) Read the entire page →
From page 94... ... Guide to Truck Activity Data for Emissions Modeling D-10 D.6 Findings from Sample Data D.6.1 Locations of Extended Idle Events Figure D.9 shows an overlay of extended idling locations (red dots) with truck stops from the databases (blue dots) Read the entire page →
From page 95... ... Guide to Truck Activity Data for Emissions Modeling D-11 D.6.2 Stopping Activity by Duration The definition of hotelling depends on the minimum and maximum thresholds of vehicle stopping period. The dataset was used to guide the selection of these thresholds. Read the entire page →
From page 96... ... Guide to Truck Activity Data for Emissions Modeling D-12 Figure D.11 Number of Extended Idling Events by Idling Duration Figure D.12 shows the fraction of idle events by duration, comparing the Vnomics data with MOVES data as presented in Table 12-10 of U.S. Read the entire page →
From page 97... ... Guide to Truck Activity Data for Emissions Modeling D-13 hours in MOVES. The Vnomics distributions contrast with the MOVES distributions where the Vnomics distributions show trip starts peaking in the mid-afternoon and trip ends peaking in the morning, indicating a preference for nighttime driving. Read the entire page →
From page 98... ... Guide to Truck Activity Data for Emissions Modeling D-14 Figure D.14 Percent of Hotelling Activity by Hour of the Day Source of MOVES data: U.S. Read the entire page →
From page 99... ... Guide to Truck Activity Data for Emissions Modeling D-15 Table D.5 Comparison of Hotelling Rates Stopping Period Key Off (hours) KeyOn_EngOff (hours) Read the entire page →
From page 100... ... Guide to Truck Activity Data for Emissions Modeling D-16 Figure D.15 State of Key and Engine during Stopping Periods The MOVES national default for hotelling rate with main engine idling is 0.0554* 0.7 = 0.03878 hours per rural restricted VMT. Read the entire page →
From page 101... ... Guide to Truck Activity Data for Emissions Modeling D-17 The MOVES default assumes eight hours of hotelling for every 10 hours of operation. It is not surprising that it appears to significantly overestimate extended idling activity, since it does not account for factors such as truckers shutting off the engine, team driving, or periods of no activity that are not "hotelling" events. Read the entire page →
From page 102... ... Guide to Truck Activity Data for Emissions Modeling D-18 limitations for use in developing locally specific MOVES truck activity inputs. Some general observations about the data sources in this case study include: • The Vnomics data are unique among the datasets investigated for this project in that they include ECU data. Read the entire page →
From page 103... ... Guide to Truck Activity Data for Emissions Modeling D-19 the late evening hours. The hourly distribution is primarily of importance if MOVES outputs are to be used for peak-hour hot-spot analysis or for air quality modeling. Read the entire page →

From page 85...

... Guide to Truck Activity Data for Emissions Modeling D-1 Appendix D Case Study #4: Truck Extended Idling and Starts from Fleet Telematics Data D.1 Emissions Model Inputs Supported • Truck hotelling (distribution of extended idling by hour and duration)