Issue link: https://read.dmtmag.com/i/46658
Disaster Management purposes, a decision was made to use pre-calculated driving times when building the Vancouver SDSS. Although these times don't reflect real-time traffic considerations, they provide an accurate estimate of the driving time between a particular incident loca- tion and each of the hospitals in the community. With respect to bed capacity, the goal was to provide up-to- date information by enabling two-way communication between hospitals and paramedics at the incident location(s) through the use of the SDSS. To increase ease of use and interpretation as well as accommodate the varying levels of computer literacy among the target user group (paramedics/ health-care professionals) and the chaotic nature of the situations in which this type of SDSS would be used, this particular system was developed on a Web platform. The Web-based platform also enables the system to be used anywhere with an Internet connec- tion, eliminating the need for additional software and enabling the system to be automatically updated. SDSS Development/Utilization The system in Vancouver was developed using the ArcGIS server API in conjunction with Microsoft lFigure 4. In addition to providing information to determine evacuation hospitals, the model also aims to evenly distribute patients among hospitals. The utilization level shows the percentage of beds available at each hospital. ASP.NET technology. Driving-time calculations were made using the ArcGIS Network Analyst extension with road-network data provided by a local British Columbia company. Impedance values were given to traffic lights (10 seconds) and stop signs (five seconds) based on those typically encountered by ambulance drivers; comparisons of real vs. SDSS-simulated driving times indicated that the SDSS times were fairly accurate. To achieve faster results, the SDSS driving times were pre-calculated from each point on the road net- work to each of the hospitals in the metro Vancouver area (there are future plans to incorporate real-time driving-time calculations into the model). These then were used to create a driving-time reference table accessed instantaneously upon insertion of an inci- dent location into the SDSS. A results page appears immediately after inserting lFigure 3. In the Web-based SDSS interface, the map window is where the MCI location is inserted. The results window displays information regarding evacuation hospitals. 24 GEO W ORLD / O CTOBER 2O11 the incident location and running the SDSS, providing information regarding bed capacity and driving time to each of the hospitals in the metro Vancouver area. For bed capacity to remain up to date, the SDSS provides a utility that enables users to update the model every time a patient is sent to a hospital. This information then is inserted into a central database that's accessible by all users. This is particularly useful in cases where multiple incidents occur simultaneously, as it enables users at each location to access real-time bed capacity. In addition to providing users with driving-time and bed-capacity information, the model also uses an algo- rithm based on estimated driving time, real-time bed capacity and expected hospital arrival time to suggest the optimal hospital to which the next patient should be evacuated. Although this algorithm is intended to control patient flow by evenly distributing patients among those hospitals that can provide adequate care, it's not intended to replace the expertise of health-care professionals and can be overridden by these personnel if required.