由路段交通流量反估出行OD矩阵技术的应用

Application of entropy maximization model for estimating OD trip matrices

由路段交通流量来估计交通出行 OD( origin-destination)矩阵 ,是一种先进的技术方法。它为获得 OD矩阵这种代价高昂而意义重要的交通需求信息提供了有效手段 ,并缓解了对难度很高的大规模居民出行调查的需要。利用一个适合实际应用的交通流量反估 OD矩阵模型——熵极大模型 ( entropy maximization model) ,在结合阐明其基于极大似然估计的数学原理的同时 ,重点给出适于计算机编程的模型迭代求解详细算法 ,并提出使用 Bi-Section和Newton-Raphson组合算法来保证其中非线性方程求解的稳定性和效率。进一步给出了使用熵极大模型的 OD矩阵估计软件包的设计思路和程序构架。该技术可直接指导高度实用化的

To reduce the effort needed for frequent large scale OD (origin destination) surveys, the approach for estimating OD trip matrices from road traffic counts is preferred. Based on previous research achievements, the authors describe, theoretically and systematically, the Entropy Maximization (EM) model for estimating OD matrices. A practicable iterative numerical routine is presented in detail for computation purpose. Combined Bi section and Newton Raphson algorithm is adopted to solve the involved nonlinear equations, which provides the promotion on both robustness and efficiency of the approach. The architecture and design of the software as the application of the EM model are given. So the method will directly contribute to the implementation of estimating OD matrices from traffic counts.