The Study on Safety Evaluation of Evacuation in a Large Supermarket

AbstractSupermarkets are typical crowded public places where the accident caused by evacuation congestion in any emergency event happened easily. In this paper, the number of customers, the ratio of personnel's age, the walking speed and other basic datas were obtained by present observation in a typical supermarket. On this basis, the evacuation scenarios were simulated by buildingEXODUS software for this supermarket and the safety performance was analysed. At last, the safety measures of supermarket management for evacuation were proposed

Efficient calculation of the robustness measure R for complex networks

In a recent work, Schneider et al. (2011) proposed a new measure R for network robustness, where the value of R is calculated within the entire process of malicious node attacks. In this paper, we present an approach to improve the calculation efficiency of R, in which a computationally efficient robustness measure R' is introduced when the fraction of failed nodes reaches to a critical threshold qc. Simulation results on three different types of network models and three real networks show that these networks all exhibit a computationally efficient robustness measure R'. The relationships between R' and the network size N and the network average degree are also explored. It is found that the value of R' decreases with N while increases with . Our results would be useful for improving the calculation efficiency of network robustness measure R for complex networks.Peer ReviewedPostprint (author's final draft

Prediction and control on vibro-acoustic environment of vessel engine room floating cabins

With the engine room of certain training ship for navigation teaching being the prototype, the numerical model was developed for three cabins with floating cabin to predict the structure-borne noise (SBN) in ship cabins. The finite element model of multi-tanks structure was built when the vibro-acoustic coupling system was simplified. The predicted results for SBN were compared with the measurements done on a cabin mock-up. The effects of vibration isolator and constraint damping materialss were investigated. Comparisons of the predicted results and the experimental results showed that the developed model could be an effective tool for predicting SBN in ship cabins. The elastic mount installed positions on the auxiliary diesel engine are selected as the force excitation points. The finite element/boundary element method to predict sound pressure level (SPL) of the machinery control room and mechanical workshops of the ship, The sound pressure color nephogram of symmetrical field points on two sides is compared and analyzed, thus the degree of contribution of all bulkheads to the SPL in the right ear position of the duty engineer is acquired. And the floating cabins design based on floating floor is verified to effectively decrease the noise in cabin. The method and process of predicting vibration and sound of the vessel engine room are summarized, which could be a reference for reducing vibration and noise of ships