Data

Single-Channel IVHS Communication Architecture

Linnartz, Jean-paul M. G.
1994

This report documents a single-channel architecture offering two-way communication between vehicles and a fixed communication infrastructure. Part I discusses the technical advantages and disadvantages of a dedicated Intelligent Vehicle Highway Systems (IVHS) communications infrastructure versus the use of a hybrid system involving several existing communication networks. Aspects such as spectrum efficiency, message capacity, and network performance are described. Part II proposes a network architecture that offers several transmission services essential to IVHS communications, using only...

Fault Detection and Identification with Application to Advanced Vehicle Control Systems: Final Report

Douglas, R. K.
Speyer, J. L.
Mingori, D. L.
Chen, R. H.
Malladi, D. P.
Chung, W. H.
1996

This study reports on a preliminary design of a health monitoring system for automated vehicles. A new detailed nonlinear vehicle simulation which extends the current simulation is documented and will be used as a future testbed for evaluating the performance of the health monitoring system. A health monitoring system has been constructed for the lateral and longitudinal modes that monitors twelve sensors and three actuators. The approach is to fuse data from dissimilar instruments using modeled dynamic relationships and fault detection and identification filters.

Traffic Management Systems Performance Measurement: Final Report

Banks, James H.
Kelly, Gregory
1997

This report documents a study of performance measurement for Transportation Management Centers (TMCs). Performance measurement requirements were analyzed, data collection and management techniques were investigated, and case study traffic data system improvement plans were prepared for two Caltrans districts.

Urban Attractors: Discovering Patterns in Regions of Attraction in Cities

Alhazzani, May
Alhasoun, Fahad
Alawwad, Zeyad
González, Marta C.
2021

Understanding the dynamics by which urban areas attract visitors is important in today’s cities that are continuously increasing in population towards higher densities. Identifying services that relate to highly attractive districts is useful to make policies regarding the placement of such places. Thus, we present a framework for classifying districts in cities by their attractiveness to daily commuters and relating Points of Interests (POIs) types to districts’ attraction patterns. We used Origin-Destination matrices (ODs) mined from cell phone data that capture the flow of trips between...

Aviation Infrastructure Performance and Airline cost: A Statistical Cost Estimation Approach

Hansen, Mark M.
Gillen, David
Djafarian-Tehrani, Reza
2001

The relationship between the performance of the US National Airspace System (NAS) and airline costs is examined by estimating airline cost functions that include NAS performance metrics as arguments, using quarterly data for 10 US domestic airlines. Performance metrics that vary by airline and quarter are developed by applying principal component analysis to seven underlying variables, including average delay, delay variance, and the proportion of flights that is cancelled. This analysis reveals that variation in the seven variables can be adequately captured by three or fewer factors,...

Fleet Size and Spill for UAM Operation under Uncertain Demand

Cao, Shangqing
Jiang, Xuan
Onat, Emin Burak
Zou, Bo
Hansen, Mark
Sengupta, Raja
Chakrabarty, Anjan
2024

Variation and imbalance in demand poses significant challenges to Urban Air Mobility (UAM) operations, affecting strategic decisions such as fleet sizing. To study the implications of demand variation on UAM fleet operations, we propose a stochastic passenger arrival time generation model that uses real-world data to infer demand distributions, and two integer programs that compute the zero-spill fleet size and the spill-minimizing flight schedules and charging policies, respectively. Our numerical experiment on a two-vertiport network shows that spill in relatively inelastic to fleet size...

The California Aviation System: Current Status and Recent Trends

Hansen, Mark M.
Gosling, Geoffrey D.
Kettunen, Tarja
Wilkins, Erik
2002

This report presents statistical information on passenger and cargo traffic, aircraft activity and delays at California airports. Five main topics are considered: passenger enplanements, air travel origin and destination (O-D) patterns, air cargo activity, aircraft operations, and airport delays. In most cases, we present data for the state as a whole, major regions within the state, and major airports within each region. Most of the data are compiled on an annual basis for the years from 1980 to 2000. The report concludes with a discussion of the changes in activity in the California...

Operation of Traffic Signal Systems in Oversaturated Conditions, Volume 2: Final Report

Gettman, Douglas
Madrigal, Guillermo
Allen, Stewart
Boyer, Tricia
Walker, Sara
Tong, Jiaxin
Phillips, Stacie
Liu, Henry
Wu, Xinkai
Hu, Heng
Abbas, Montasir
Adam, Zain
Skabardonis, Alex
2014

This research project included work in several areas related to the operation of traffic signal systems in oversaturated traffic conditions. Quantitative measures were developed that characterize the intensity of oversaturated conditions and can be calculated based on high-resolution data from advance detectors and second-by-second phase timing data. The technique measures the length of the overflow queue at the beginning of the red light and estimates the amount of green time that is wasted either by dispersing this overflow queue or by vehicles that cannot proceed due to a downstream...

Queue Spillback Detection and Signal Control Strategies Based on Connected Vehicle Technology in a Congested Network

Rivadeneyra, Aldo Tudela
Argote, Juan
Skabardonis, Alexander
Transportation Research Board
2014

Queue spillbacks create excessive delays and may result in gridlock conditions in signal controlled networks. The information from Connected Vehicles (CV) offers significant potential for developing improved signal control strategies. The paper presents the development and testing of algorithms for queue spillback detection and control in congested grid networks with CV data. Three control strategies were developed: perimeter control, spillback-based phase changing control strategy, and reduction in the system-wide cycle time with additional green times to the links with the highest...

Proposed Asymmetric Microscopic Traffic Flow Theory

Skabardonis, Alexander
Yeo, Hwasoo
Transportation Research Board
2009

The paper presents a microscopic asymmetric traffic flow theory based on detailed analysis of individual vehicle trajectories from the Next-Generation Simulation (NGSIM) database. The findings clearly show the asymmetry in vehicle’s acceleration and deceleration and define five traffic phases: free flow, acceleration, deceleration, coasting, and stationary. The proposed theory provides detailed description and mechanism of phase transitions. Extensions of the basic theory address common driver behavioral characteristics such as maneuvering error and anticipation. The application of the...