ITS Berkeley

Ensemble Kalman Filter Based State Estimation in 2D Shallow Water Equations Using Lagrangian Sensing and State Augmentation

Tossavainen, Olli‐Pekka
Percelay, Julie
Tinka, Andrew
Wu, Qingfang
Bayen, Alexander M.
2008

We present a state estimation method for two-dimensional shallow water equations in rivers using Lagrangian drifter positions as measurements. The aim of this method is to compensate for the lack of knowledge of upstream and downstream boundary conditions in rivers that causes inaccuracy in the velocity field estimation by releasing drifters equipped with GPS receivers. The drifters report their positions and thus provide additional information of the state of the river. This information is incorporated into shallow water equations by using Ensemble Kalman Filtering (EnKF). The proposed...

Convex Formulations of Aggregate Network Air Traffic Flow Optimization Problems

Work, Daniel B.
Bayen, Alexandre M.
2008

The problem of regulating air traffic in the en route airspace of the national airspace system is studied using an Eulerian network model to describe air traffic flow. The evolution of traffic on each edge of the network is modeled by a modified Lighthill-Whitham-Richards partial differential equation. We pose the problem of optimal traffic flow regulation as a continuous optimization program in which the partial differential equation appears in the constraints. The equation is transformed with a variable change which removes t nonlinearity in the control variables and enables us to use...

Convex Formulations of Air Traffic Flow Optimization Problems

Work, Daniel B.
Bayen, Alexandre M.
2008

The problem of regulating air traffic in the en route airspace of the National Airspace System is studied using a Eulerian network model to describe air traffic flow. The evolution of traffic on each edge of the network is modeled by a modified Lighthill-Whitham-Richards partial differential equation. The equation is transformed with a variable change, which makes it linear and enables us to use linear finite difference schemes to discretize the problem. We pose the problem of optimal traffic flow regulation as a continuous optimization program in which the partial differential equation...

An Ensemble Kalman Filtering Approach to Highway Traffic Estimation Using GPS Enabled Mobile Devices

Work, Daniel B.
Tossavainen, Olli‐Pekka
Blandin, Sébastien
Bayen, Alexandre M.
Iwuchukwu, Tochukwu
Tracton, Kenneth
2008

Traffic state estimation is a challenging problem for the transportation community due to the limited deployment of sensing infrastructure. However, recent trends in the mobile phone industry suggest that GPS equipped devices will become standard in the next few years. Leveraging these GPS equipped devices as traffic sensors will fundamentally change the type and the quality of traffic data collected on large scales in the near future. New traffic models and data assimilation algorithms must be developed to efficiently transform this data into usable traffic information. In this work, we...

Boundary Data Reconstruction for Open Channel Networks Using Modal Decomposition

Wu, Q.
Litrico, X.
Bayen-Poisson, Aurélie
2008

This article presents a method to estimate flow variables for an open channel network governed by first-order, linear hyperbolic partial differential equations and subject to periodic forcing. The selected external boundary conditions of the system are defined as the model input; the flow properties at internal locations, as well as the other external boundary conditions, are defined as the output. A spatially-dependent transfer matrix in the frequency domain is constructed to relate the model input and output. A data reconciliation technique efficiently eliminates the error in the...

Preface

Bastin, George
Bayen, Alexandre M.
2009

Management of canal networks at the age of information technology. With the miniaturization of sensors and their decreasing costs, the paradigm of instrumentation of the built infrastructure and the environment has now been underway for several years, leading to numerous successful and sometimes spectacular realizations such as the instrumentation of the Golden Gate with wire- less sensors a few years ago. The convergence of communication, control and sensing on numerous platforms including multi-media platforms has enabled engineers to augment physical infrastructure systems with an...

Réconciliation de Données d'un Réseau Hydraulique à Surface Libre à L'aide de la Décomposition Modale

Wu, Qingfang
Litrico, Xavier
Bayen, Alexandre M.
2009

Data reconciliation of an open channel flow network using modal decomposition.

Improved Power Grid Stability and Efficiency with a Building-Energy Cyber-Physical System

Piette, Mary Ann
Bayen, Alexandre M.
2009

This position article outlines some challenges of demand response in the context of the power grid and its interaction with buildings. We describe significant issues in energy-efficient operation of buildings, in particular questions such as system reliability, risk management and environmental impact. We also outline a strategy for the development of new technologies for a cyber-physical infrastructure system that integrates management of smart buildings with management of the power grid. Specific emphasis is given to the interaction of physical and computational processes through sensing,...

Guaranteed Bounds on Highway Travel Times Using Probe and Fixed Data

Claudel, Christian G.
Bayen, Alexandre M.
2009

This article investigates the problem of incorporating mobile probe data collected from GPS equipped cell phones into estimation algorithms for travel time. We use kinematic wave theory to create a modeling framework capable of incorporating trajectory data into the model. The problem of including loop detector data in this model is performed using a standard approach available in the literature. The problem of fusing this data with probe data is formulated using the Moskowitz function, which results from kinematic wave theory. Using this formulation, two linear programs are posed to...

Delay Pattern Estimation for Signalized Intersections Using Sampled Travel Times

Ban, Xuegang (Jeff)
Bayen, Alexandre M.
2009

Intersection delays are the major contributing factor to arterial delays. Methods to estimate intersection delay patterns by using measured travel times are studied. The delay patterns provide a way to estimate the delay for any vehicle arriving at the intersection at any time, which is useful for providing time-dependent intersection delay information to the driving public. The model requires sampled travel times between two consecutive locations on arterial streets, one upstream and the other downstream of a signalized intersection, without the need to know signal timing or traffic flow...