The Critical Cluster Model (CCM) is an optimization model assessing the evacuation risk on the scale of neighborhoods. The static evacuation risk in the CCM is measured by Bulk Lane Demand (BLD) -an index that solely depends on network structure and population of evacuees. The advantage of the CCM is having less input parameters and with relatively smaller computational cost. Moreover, the process of risk assessment by the CCM is a global optimization process. For this reason, the CCM provides a relatively ideal solution for planning emergency traffic evacuation in open spaces. Considering that hazard installations in urban areas are becoming an increasing threat to urban safety, in the paper we proposed an evacuation risk assessment model with consideration of such installations. This model was developed on the basis of the CCM by introducing two important factors: the accident risk impact factor which was negatively correlated with distance, representing the impact of hazard installation; the evacuation direction which was under the consideration of evacuating away from the hazard installation, providing feasible evacuation routes. Finally, an application of the new model was presented for Beijing, China with the support of Geographical Information System (GIS). urban public safety, Critical Cluster Model (CCM), hazard installation, traffic evacuation risk, Geographical Information System (GIS) Citation: Li Q, Chen X, Chen J, et al. An evacuation risk assessment model for emergency traffic with consideration of urban hazard installations.Due to centralization and enormous fluxes of population and productive elements in urban areas, the problems of urban public safety are characterized as unexpected with high frequency and severe impacts [1]. Once a devastating incident occurs, it can easily result in massive loss of life and property, even serious threats to economical development and political stabilization of the whole country. Generally, the sources leading to public safety problems are categorized into natural disaster, accident, public health events and social security events [2]. No matter which kind of incident occurs, it is urgently required to carry out an efficient evacuation for avoiding more people to be affected.In the past decades, the importance on evacuation in enclosed space (large building, ship, airplane, etc.) has attracted extensive concerns from the public and government. A great number of evacuation models have been developed based on computer simulation technology, such as EXITT, EGRESS, SIMULEX, EXODUS and so on [3][4][5][6]. In China, although the relevant research is just at an early stage, some representative models have also been put forward, such as the grid model, escape model in fire disaster, multiagent based evacuation model [7][8][9]. In addition to evacuation in enclosed spaces, more and more attentions have recently been shifted to the study of emergency traffic evacuation in open spaces. The primary concern of these studies was how to utilize the existing transportation net...

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With the wind power increasing quickly, its impact on power system becomes greater, thus the dynamic simulation study on grid-connected wind power generators has a significant importance. This paper focuses on introducing the quasi-steady-state approximation method into analyzing the operation characteristics of grid-connected doubly-fed wind power generators. Based on the detailed dynamic model of a variable-speed constant-frequency (VSCF) doubly-fed wind power generator, which consists of wind speed model, the integrated model of wind turbine and drive system, pitch angle control model, converter control model, and the integrated model of generator and converter, the quasi-steady-state approximation method is introduced and applied to simplify the detailed dynamic model to be an order-reduced model, that is, the quasi-steady-state (QSS) model. The accuracy of the QSS model is shown by comparing simulation results of QSS model and the detailed model.

In this paper, by considering the irradiation-enhanced diffusion, a combination of effective free energy model and the thermodynamic model was used for studying the phase relationships in the U-Ti and U-V binary system under irradiation. The steady-state dynamical phase diagrams of U-Ti and U-V binary alloys under different irradiation intensities were calculated and compared with the conventional thermodynamic equilibrium phase diagram. The calculated results show that under irradiation the high-temperature stable (βTi, γU) and (γU,V) phases were stabilized at relatively low temperature resulting in invariant reactions at relatively low temperature. In addition, with the increase of the irradiation intensity, the temperature of the invariant reactions increased, and the phase regions of the (βTi, γU) and (γU,V) also increased.