Research On Locating City Emergency Shelters

For the past few years, it shall be realized that with the frequent appearance ofnatural disasters and accidents, our city is faced with great challenges in terms of itssociety, economy, traffic and ecological environment. It is more serious for big citieswith large population and crowded buildings, because any major disaster will putpeople’s lives and property in danger and also cause terrible threat to the citydevelopment and the stability of the whole society. As a well-being infrastructure toevacuate and rehouse victims, the construction of city emergency shelters will be theimportant guarantee for the city’s public security when the project gets scientificallyand reasonable layout. In the process of working over the layout and selecting sitesfor emergency shelters, the government and society need to be always focusing onbalancing social benefit with economic cost, with the purpose of allocating theresources for disaster prevention and reduction efficiently.Upon summing up the study over emergency services and selection ofemergency shelter sites at home and abroad, this paper takes three restrictive issuesinto account, namely capacity limit, effective emergency distance as well asconstruction cost. It also transforms the traditional model of site selection for setcovering and maximal covering, and moves forward to design the sit-selection modelfor maximal covering with limited service capacity and that for set covering withflowing population, considering the unignorable large population flow between theurban and suburban areas in daytime.Aiming to covering more sites which need service, the site-selection model formaximal covering with limited service capacity refers to a model to maximize theeffective covering range of service function of shelters when the constructioninvestment is not enough. On comparison, the site-selection model for set coveringwith flowing population has the purpose of lowering the total construction cost to themost at the first phase while minimizing the sum of evacuation routes for all people in view of population flow in daytime, in the premise of covering all sites needingshelters.At the same time, this paper collects and reorganizes figures for the landresources, neighborhood committee location and population size, on the basis ofanalyzing and summarizing the construction status of Shanghai emergency shelters,site-selecting principles, influencing factors and current problems. And it alsostudies the population flow and possible needs of emergency shelters in Shanghai indaytime, in order to determine all parameters for the model and carry out theempirical study for a large-scaled overall planning for the set covering with flowingpopulation, making use of the solving function of AIMMS. Meanwhile, the authormatches the paper with Shanghai geographic data, utilizes the processing function ofGIS over data and graphics and visually reveals the study results of the model.