广播设施是开放性公共场所安全管理中最灵活有效的设施之一,为使其布局更有利于应急疏散,借鉴解决最大覆盖问题的方法,构建广播设施选址最优化模型。模型中考虑了声音传播中声压级的衰减性质及广播设施之间的干扰现象,兼顾最大覆盖与最小干扰的平衡,并以不被覆盖的信息接收点数与受到干扰的信息接收点数的加权和最小化作为模型的优化目标。将此模型应用于北京市什刹海景区,采用遗传算法求解5种情景下的选址方案,并与现有方案进行比较。结果表明,3种类型信息接收点在不同加权系数和不同广播设施数下的构成比例是不同的,优化选址方案的效果存在很大差异,应根据实际需求制定合理的广播设施选址方案。
Setting broadcast facilities is one of the most flexible and effective measures to meet the requirements for security management of open public places. To make emergency evacuation more effective with the help of broadcast facilities, the broadcast facilities should be located carefully. Considering the attenuating property of sound pressure level and across interference among the different broadcast facilities during the sound propagation process, an optimal location model was built for broadcast facilities based on method for solving maximum covering location problem, in which the weighted minimum of numbers of both non-covered and information interfered points was taken as objective function to balance maximum coverage and minimum interference. The model was applied to a case study of Shichahai lake area in Beijing. The genetic algorithm was used to obtain optimal location schemes under 5 different scenarios. In- fluences of the number of broadcast facilities for different location scheme were discussed. The results show that effects of different location schemes and the numbers of broadcast facilities were obviously different, and that in the actual application, reasonable location schemes should be set out based on practical needs.