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• 1. [Article] Methodology for Estimating Bicyclist Acceleration and Speed Distributions at Intersections

  As cities across North America install infrastructure to accommodate a growing number and variety of bicyclists, installation of bicycle-specific traffic signals is a common design element. A recent survey ...

  Citation × Citation Citation Abstract Copy Title: Methodology for Estimating Bicyclist Acceleration and Speed Distributions at Intersections Author: Figliozzi, Miguel A., Wheeler, Nikki, Monsere, Christopher M. Year: 2013 As cities across North America install infrastructure to accommodate a growing number and variety of bicyclists, installation of bicycle-specific traffic signals is a common design element. A recent survey showed a lack of consistency in design and timing. In particular, minimum green signal timing is highly dependent on the assumed acceleration and speed performance of bicyclists, but no detailed methodology exists to estimate these performance values. However, recent American Association of State Highway and Transportation Officials (AASHTO), Caltrans and National Association of City Transportation Officials (NACTO) documents require that an adequate clearance interval shall be provided, and that in determining this minimum interval field investigation of bicyclists’ speeds is recommended. Furthermore, even if detailed video trajectories are available, the determination of a value for field speed and acceleration is not trivial because values of speeds and accelerations are a function of time and individual bicyclist performance. The purpose of this research is to develop and apply a general methodology to estimate bicyclists’ acceleration and speed for traffic signal timing applications. Utilizing physical equations of motion, this research analytically derives expressions that can be used to classify an individual bicyclist’s performance as a function of the observed acceleration profile. The analysis indicates that four basic acceleration profiles are possible and the profiles can be obtained using a parsimonious field-data collection method. The methodology is successfully applied to two intersections in Portland, OR. A detailed statistical analysis shows that the results are intuitive and that the methodology successfully categorizes bicyclists’ performance variations due to topography or demographic characteristics. Title: Methodology for Estimating Bicyclist Acceleration and Speed Distributions at Intersections Author: Figliozzi, Miguel A., Wheeler, Nikki, Monsere, Christopher M. Year: 2013 As cities across North America install infrastructure to accommodate a growing number and variety of bicyclists, installation of bicycle-specific traffic signals is a common design element. A recent survey showed a lack of consistency in design and timing. In particular, minimum green signal timing is highly dependent on the assumed acceleration and speed performance of bicyclists, but no detailed methodology exists to estimate these performance values. However, recent American Association of State Highway and Transportation Officials (AASHTO), Caltrans and National Association of City Transportation Officials (NACTO) documents require that an adequate clearance interval shall be provided, and that in determining this minimum interval field investigation of bicyclists’ speeds is recommended. Furthermore, even if detailed video trajectories are available, the determination of a value for field speed and acceleration is not trivial because values of speeds and accelerations are a function of time and individual bicyclist performance. The purpose of this research is to develop and apply a general methodology to estimate bicyclists’ acceleration and speed for traffic signal timing applications. Utilizing physical equations of motion, this research analytically derives expressions that can be used to classify an individual bicyclist’s performance as a function of the observed acceleration profile. The analysis indicates that four basic acceleration profiles are possible and the profiles can be obtained using a parsimonious field-data collection method. The methodology is successfully applied to two intersections in Portland, OR. A detailed statistical analysis shows that the results are intuitive and that the methodology successfully categorizes bicyclists’ performance variations due to topography or demographic characteristics. Close

• 2. [Article] Economic and Technological Analysis of the Key Factors Affecting the Competitiveness of Electric Commercial Vehicles

  Electric commercial vehicles’ (ECVs) energy costs are almost four times less expensive than conventional diesel trucks, on a per-mile basis, at current USA market values. However, ECVs are approximately ...

  Citation × Citation Citation Abstract Copy Title: Economic and Technological Analysis of the Key Factors Affecting the Competitiveness of Electric Commercial Vehicles Author: Feng, Wei, Figliozzi, Miguel A. Year: 2013 Electric commercial vehicles’ (ECVs) energy costs are almost four times less expensive than conventional diesel trucks, on a per-mile basis, at current USA market values. However, ECVs are approximately three times more expensive in terms of vehicle purchase costs. In addition, electric vehicles are simpler and cheaper to maintain there are more uncertainties associated to the life and long-term costs of the ECV batteries. Furthermore, there are limitations in terms of miles driven per day without recharging. These economic and technological tradeoffs motivate this research. Utilizing a fleet replacement optimization framework, a wide range of scenarios, and current USA market data this research finds the key economic and technological breakeven values where ECVs become competitive against conventional diesel counterparts. The results clearly indicate that only in scenarios with high utilization (over 16,000 miles per year per truck) the electric vehicles are competitive, this is especially valid if a battery replacement is not required before the electric commercial vehicle is replaced. The breakeven analysis results show that a 9–27% ECV price reduction can greatly increase their competitiveness when vehicles are driven over 12,000 miles per year. Title: Economic and Technological Analysis of the Key Factors Affecting the Competitiveness of Electric Commercial Vehicles Author: Feng, Wei, Figliozzi, Miguel A. Year: 2013 Electric commercial vehicles’ (ECVs) energy costs are almost four times less expensive than conventional diesel trucks, on a per-mile basis, at current USA market values. However, ECVs are approximately three times more expensive in terms of vehicle purchase costs. In addition, electric vehicles are simpler and cheaper to maintain there are more uncertainties associated to the life and long-term costs of the ECV batteries. Furthermore, there are limitations in terms of miles driven per day without recharging. These economic and technological tradeoffs motivate this research. Utilizing a fleet replacement optimization framework, a wide range of scenarios, and current USA market data this research finds the key economic and technological breakeven values where ECVs become competitive against conventional diesel counterparts. The results clearly indicate that only in scenarios with high utilization (over 16,000 miles per year per truck) the electric vehicles are competitive, this is especially valid if a battery replacement is not required before the electric commercial vehicle is replaced. The breakeven analysis results show that a 9–27% ECV price reduction can greatly increase their competitiveness when vehicles are driven over 12,000 miles per year. Close

• 3. [Article] The Application of Smart Phone, Weight-Mile Truck Data to Support Freight-Modeling, Performance Measures and Planning

  Oregon is one of the few states that currently charge a commercial truck weight-mile tax (WMT). The Oregon Department of Transportation (ODOT) has developed a data-collection system – Truck Road Use Electronics ...

  Citation × Citation Citation Abstract Copy Title: The Application of Smart Phone, Weight-Mile Truck Data to Support Freight-Modeling, Performance Measures and Planning Author: Bell, Katherine E., Figliozzi, Miguel A. Year: 2013 Oregon is one of the few states that currently charge a commercial truck weight-mile tax (WMT). The Oregon Department of Transportation (ODOT) has developed a data-collection system – Truck Road Use Electronics (TRUE) – to simplify WMT collection. The TRUE system includes a smart phone application that collects and records Global Positioning System (GPS) data. The TRUE data has enormous advantages over GPS data used in previous research due to its level of geographic detail and the potential to also integrate trip origin and destination, vehicle class, and commodity-type data. This research evaluates the accuracy of the TRUE data and demonstrates its use for significant ODOT ancillary applications. Specifically, ancillary applications that address ODOT freight modeling, performance measures, and planning needs are explored. The use of the data for highly accurate trip-generation rates and mobility performance measures is demonstrated. In addition, it is shown that the TRUE data has strong potential to be used for safety, accessibility and connectivity, system condition and environmental stewardship performance measures. The potential use of the TRUE data for emissions estimates that take into account truck-type details, truck weight and detailed speed profiles is considered. Results indicate that TRUE data, integrated with ODOT weigh-in-motion (WIM) data, will greatly improve the accuracy of emission estimates at the project and regional level. This research confirms the potential use of the TRUE data for significant ancillary applications and demonstrates the regional value of the TRUE data to enhance existing freight modeling, performance measures and planning. Title: The Application of Smart Phone, Weight-Mile Truck Data to Support Freight-Modeling, Performance Measures and Planning Author: Bell, Katherine E., Figliozzi, Miguel A. Year: 2013 Oregon is one of the few states that currently charge a commercial truck weight-mile tax (WMT). The Oregon Department of Transportation (ODOT) has developed a data-collection system – Truck Road Use Electronics (TRUE) – to simplify WMT collection. The TRUE system includes a smart phone application that collects and records Global Positioning System (GPS) data. The TRUE data has enormous advantages over GPS data used in previous research due to its level of geographic detail and the potential to also integrate trip origin and destination, vehicle class, and commodity-type data. This research evaluates the accuracy of the TRUE data and demonstrates its use for significant ODOT ancillary applications. Specifically, ancillary applications that address ODOT freight modeling, performance measures, and planning needs are explored. The use of the data for highly accurate trip-generation rates and mobility performance measures is demonstrated. In addition, it is shown that the TRUE data has strong potential to be used for safety, accessibility and connectivity, system condition and environmental stewardship performance measures. The potential use of the TRUE data for emissions estimates that take into account truck-type details, truck weight and detailed speed profiles is considered. Results indicate that TRUE data, integrated with ODOT weigh-in-motion (WIM) data, will greatly improve the accuracy of emission estimates at the project and regional level. This research confirms the potential use of the TRUE data for significant ancillary applications and demonstrates the regional value of the TRUE data to enhance existing freight modeling, performance measures and planning. Close

• 4. [Article] Freight Distribution Problems in Congested Urban Areas: Fast and Effective Solution Procedures to Time-Dependent Vehicle Routing Problems

  Congestion is a common phenomenon in all medium to large cities of the world. Reliability of freight movement in urban areas is an important issue to manufacturing or service companies whose operation ...

  Citation × Citation Citation Abstract Copy Title: Freight Distribution Problems in Congested Urban Areas: Fast and Effective Solution Procedures to Time-Dependent Vehicle Routing Problems Author: Figliozzi, Miguel A. Year: 2011 Congestion is a common phenomenon in all medium to large cities of the world. Reliability of freight movement in urban areas is an important issue to manufacturing or service companies whose operation is based in just-in-time approaches. These companies tend to provide high value or time sensitive products/services. As congestion increases, carriers face increasing challenges to satisfy their time sensitive customers in an economical way. Route designs or schedules which require long computation times or ignore travel time variations will result in inefficient and suboptimal solutions. Poorly designed routes that lead freight vehicles into congested arteries and streets not only increases supply chain and logistics costs but also exacerbate externalities associated with freight traffic in urban areas such as greenhouse gases, air pollution, noise, and accidents. Whilst it is rarely possible to entirely avoid the impacts of congestion, it is feasible to schedule operations so that the effects of congestion are minimized. Better scheduling can be effectively supported by the advent of inexpensive and ubiquitous Information and Communication Technologies (ICT). The use of mobile phone technology and on-board routing devices allows fluid communication between truck drivers and fleet operators in real-time. In such a real time operation it becomes possible to dynamically reassign vehicles, including modifying the order in which customers are served and diverting a vehicle already en-route to service another customer. However, without fast routing methods that can take advantage of real time congestion information carriers cannot reap the benefits of real-time information. From the operational point of view, congestion creates a substantial variation in travel times during peak morning and evening hours. This is problematic for all vehicle routing models which rely on a constant value to represent vehicle speeds. And while the ubiquitous availability of real time traffic information allows drivers to reactively alter routes and customer service sequences to better cope with congestion, static routing models are unable to take advantage of these advances in real-time information provision in order to proactively find adequate routing solutions. In addition, changes in travel time caused by congestion cannot be accurately represented in static models. Research in time-dependent vehicle routing problem is comparatively meager and current solution methods are inadequate for practical carrier operations which need to provide fast solutions for medium to large instances. Even faster solution methods are essential to take advantage of real time information. The major aim of this proposal is to develop and evaluate new methods for vehicle routing in congested urban areas. The emphasis will be placed on improving the running time of the existing methods. Title: Freight Distribution Problems in Congested Urban Areas: Fast and Effective Solution Procedures to Time-Dependent Vehicle Routing Problems Author: Figliozzi, Miguel A. Year: 2011 Congestion is a common phenomenon in all medium to large cities of the world. Reliability of freight movement in urban areas is an important issue to manufacturing or service companies whose operation is based in just-in-time approaches. These companies tend to provide high value or time sensitive products/services. As congestion increases, carriers face increasing challenges to satisfy their time sensitive customers in an economical way. Route designs or schedules which require long computation times or ignore travel time variations will result in inefficient and suboptimal solutions. Poorly designed routes that lead freight vehicles into congested arteries and streets not only increases supply chain and logistics costs but also exacerbate externalities associated with freight traffic in urban areas such as greenhouse gases, air pollution, noise, and accidents. Whilst it is rarely possible to entirely avoid the impacts of congestion, it is feasible to schedule operations so that the effects of congestion are minimized. Better scheduling can be effectively supported by the advent of inexpensive and ubiquitous Information and Communication Technologies (ICT). The use of mobile phone technology and on-board routing devices allows fluid communication between truck drivers and fleet operators in real-time. In such a real time operation it becomes possible to dynamically reassign vehicles, including modifying the order in which customers are served and diverting a vehicle already en-route to service another customer. However, without fast routing methods that can take advantage of real time congestion information carriers cannot reap the benefits of real-time information. From the operational point of view, congestion creates a substantial variation in travel times during peak morning and evening hours. This is problematic for all vehicle routing models which rely on a constant value to represent vehicle speeds. And while the ubiquitous availability of real time traffic information allows drivers to reactively alter routes and customer service sequences to better cope with congestion, static routing models are unable to take advantage of these advances in real-time information provision in order to proactively find adequate routing solutions. In addition, changes in travel time caused by congestion cannot be accurately represented in static models. Research in time-dependent vehicle routing problem is comparatively meager and current solution methods are inadequate for practical carrier operations which need to provide fast solutions for medium to large instances. Even faster solution methods are essential to take advantage of real time information. The major aim of this proposal is to develop and evaluate new methods for vehicle routing in congested urban areas. The emphasis will be placed on improving the running time of the existing methods. Close