To analyze the spreading regularity of the initial traffic congestion, the improved cell transmission model (CTM) is proposed to describe the evolution mechanism of traffic congestion in regional road grid. Ordinary cells and oriented cells are applied to render the crowd roads and their adjacent roads. Therefore the traffic flow could be simulated by these cells. Resorting to the proposed model, the duration of the initial traffic congestion could be predicted and the subsequent secondary congestion could be located. Accordingly, the spatial diffusion of traffic congestion could be estimated. At last, taking a road network region of Hangzhou city as an example, the simulation experiment is implemented to verify the proposed method by PARAMICS software. The result shows that the method could predict the duration of the initial congestion and estimate its spatial diffusion accurately.

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A novel approach of networked manufacturing collaboration: fractal web-based extended enterpriseAbstract The web-based extended enterprise is a complicated system devoting to manufacturing collaboration by Internet and Intranet. To simplify its implementation and operation, a novel solution, fractal web-based extended enterprise with the fractal structure and the self-organizing operation policy, is raised here. The hierarchical architecture of extended enterprise can be generated through the recursion and iteration of our proposed simple unit, named fractal-agent. And it can be operated by the concise self-similar fractal workflow. Finally, an example of fractal web-based extended enterprise is given, in which a hydraulic machine can be manufactured cooperatively through selfsimilar networked collaboration style among the manufacturers and among their internal subunits supported by the computersupported cooperative work (CSCW) information platform.

Dedicated bus lanes (DBLs) can only be used by buses in principle, so there is an intermittent waste of road resources. Coupled with increasingly serious traffic congestion, how to fully exploit the relatively surplus road resources of DBLs under the premise of guaranteeing bus priority is an issue that is worth studying. The authors propose a dynamic time slice policy for the time division multiplexing (TDM) method to share dedicated bus lanes. First, the TDM method is outlined to present the basic mechanism of the dynamic time slice policy. Subsequently, models for predicting the travel times of approaching vehicles and lane-borrowing vehicles based on TDM are established. Then, a lane-borrowing discriminative model is proposed to determine whether low-priority vehicles have the right to use the DBL at the current moment, and the time slices of DBL multiplexing are allocated based on vehicles of different types. Furthermore, to increase the operability of the method in engineering applications, a spatiotemporal control strategy for TDM is designed. Finally, the dynamic time slice policy is applied to a DBL through simulations and practical traffic experiments. The results prove the feasibility of the dynamic time slice policy.