An Expert Decision Support System for Crisis Management. Boumediene Belkhouche Reda Bakeer Salah Al-Saleh

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1 An Expert Decision Support Syste for Crisis Manageent Bouediene Belkhouche Reda Bakeer Salah Al-Saleh EECS Departent Tulane University New Orleans, LA (504) (phone) (504) (fax) Abstract An integrated odel for crisis anageent is described. The ipleentation of this odel consists of several software packages, a knowledge base, and set of expert rules. Existing rules and regulations designed specifically to tackle various types of possible crises (e.g., fire) are foralized. A prototype was ipleented to deonstrate the feasibility of such a odel. The ain purpose of the prototype is not only to siulate the growth of fire, but also to help the user anage fire hazards by providing advice to enhance the decision process and derive an optial response. Keywords: crisis anageent, expert systes, geographical inforation systes, fire odeling. EDSS Model for Crisis Manageent Crises (e.g., fires, earthquakes, oil spills) often occur suddenly without prior alar or indications. The size and ipact of a crisis vary depending on its nature, the environental circustances, and the tie and place of occurrence. Managing a crisis involves various agents/factors that affect the assessent of the crisis, its extent, and how to respond to it. To address issues related to crisis anageent autoation, we developed an Expert Decision Support Syste (EDSS) to assist anageent teas in dealing with potential crises. Our objective is to provide a reliable software odel for evaluating a crisis, odeling it, and developing an efficient plan for tackling it. Thus, we designed and ipleented a prototype that integrates the data capturing power of a Geographic Inforation Syste (GIS), the reasoning and inference capability of an Expert Syste, and the coputing power of a prograing language. Figure 1 shows the ajor coponents of the EDSS. The functionality of this syste is to process quickly available inforation related to the crisis at hand, retrieve the ipacted site database, and provide assistance with regard to: (1) identifying the paraeters under prevailing environental conditions; (2) siulating the evolution of the crisis; (3) identifying possible threats; (4) displaying iportant facilities, which ay be highly affected; and (5) suggesting a response scenario. GRAPHICAL USER INTERFACE Data base Geographical Inforation Syste Expert Syste Figure 1: EDSS Structure

2 FIRE EDSS Design and Ipleentation An appropriate exaple of a ajor crisis, and the one ephasized in this paper, is that of a fire in which risk to life and infrastructure ay be severe. A fire odel ay be a physical odel, i.e., a copy of soe real fire situation on a reduced scale, or it ay be captured by a set of atheatical equations. Most of the atheatical fire odels are hybrid systes of differential and algebraic equations, which can only be solved nuerically. A better understanding of fire phenoena and a growing database of accurate physical properties of aterials and fire characteristics have generated various atheatical and coputer odels of fire behavior. However, research of published literature reveals no integrated systes supporting the autoated anageent of such a crisis. The necessary inforation to build a fire siulation odel ay include several paraeters, such as fuel, fuel oisture, slope, wind speed and direction, weather, cliate, water, soil, and topography. This knowledge base and expert rules were collected fro several agencies and individuals. Variations of these paraeters greatly coplicate the dynaic nature of fires. Existing fire behavior odels are abstractions of an overall three-diensional process of unconfined cobustion that are linked iplicitly to the environent through heat and ass transfer feedback ([1,2]). We adopt here Rotherel's odel. To build the EDSS, we integrated ArcView (GIS), Visual Rule Studio (VSR, an expert syste), and Visual Basic. Visual Basic is used to provide the graphical user interface (GUI) and to coordinate the actions aong the other coponents. ArcView stores, displays, and updates spatial (aps) and teporal data (environental paraeters and characteristics). The Network Analyst, a coponent of ArcView, allows the users to solve a variety of probles using a wide selection of geographic aps or networks such as, streets, highways, rivers, pipelines, and electric lines. Finding the ost efficient travel route to the closest facility or fire hydrant, planning a solution based on travel tie its the ain function. VSR uses rules, regulations, and atheatical forulae to deterine the shape and the growth of a fire given the current environental paraeters. To do so, VSR calculates the required fire shape paraeters such as heat release rate, flae length, and size of shape of fire. The scale and the direction of the fire shape are sent to ArcView for display altogether with the affected site. Then VSR displays advice to help the user tackle this crisis. Plate 1 shows the process of fire siulation used by the FIRE-EDSS odel. The algorith is initiated when the user clicks on a location (x, y) on the ap. For each fire For each location {Get the coordinate of the location (x, y) Get the location inforation (below) Get the environent inforation (below) Calculate Heat Release Rate (below) Calculate the paraeters of shape of fire Display iportant inforation (below) Display the solution (below) Update the history data} Get the inforation of the location {Display the inforation of location by using ArcView for exaple size of building, area, etc.} Display the content of location by using ArcView. Display the iportant facilities for exaple closed fire hydrant, short path.} Get the fire environent {Display fuel type by using ArcView. Display weather by using database. Display Topography by using ArcView.} Calculate Heat Release Rate {By Using Expert Syste.} Calculate the paraeters of shape of fire {By using Expert Syste.} Display iportant inforation {Using ArcView and Expert Syste.} Display the solution {By using Expert Syste.} Update the history data {By using ArcView.} Plate1: Fire growth siulation process used in the FIRE-EDSS odel Testing of the Fire EDSS Model To show that the FIRE-EDSS odel is viable, it was tested under different conditions by using the sae fuel. For coparison purposes, FARSITE ([1]) siulations were also run. Table 1 shows the results and coparisons. Three tests were run by varying the wind speed. The values of the x-axis and y-axis represent the

3 diensions of the fire ellipse. The results of the FIRE-EDSS odel and FARSITE are consistent for all tests. A saple of actual output is shown in Figures 2 through 4. As shown in these figures, the FIRE-EDSS odel displays the growth of fire for specific interval ties such as 5, 10, 20 and 30 inutes. This is very useful for design and analysis, and for prediction. Wind-Speed 30 K/hr FARSITE x-axis M FARSITE y-axis EDSS x-axis EDSS y-axis Test 1 5 inutes inutes inutes inutes Wind-Speed 20 K/hr FARSITE x-axis M FARSITE y-axis EDSS x-axis EDSS y-axis Test2 5 inutes inutes inutes inutes Wind-Speed 10 K/hr FARSITE x-axis FARSITE y-axis EDSS x-axis EDSS y-axis Test 3 5 inutes inutes inutes inutes Table 1: Suary of Coparisons between FARSITE and FIRE-EDSS

4 Figure 2: Shape of fire for forest area where wind is south.

5 Figure 3: Shape of fire for forest area where wind is west.

6 Figure 4: Shape of fire for forest area where wind is north. Conclusions The EDSS ay be used not only for fire prediction or crisis anageent, but it could also be used for design and planning as follows: (1) in the water network, the syste could be used to design fire hydrants distribution; (2) it could be used to deterine where to safely locate electrical transforers away fro potentially dangerous warehouses; (3) it could be used to design and analyze the location equipent, locations of civil defense facilities, to optiize response tie. Another advantage of the EDSS is extensibility. It is possible to add other odels that operate on copletely different principles, such as the water syste, sewage syste, electrical syste without ipacting the other odels. Expert syste technology allows the rapid odification and updating of this prototype odule. Adding other odules such as a cheical spill odel or a water syste odel should not affect the perforance of the original fire odel. Tests perfored suggest that syste odeling using GIS is a proising way of bringing the odeling process within reach of any user and allowing real tie visualization over digital aps. Another iportant point concerning the developent of the EDSS odel is that the software was designed in a user-friendly anner. This allows even untrained operators to benefit fro the software. Finally, the syste is designed to be used as a training tool for new personnel.

7 Future work needs to concentrate on substantiating EDSS using ore observed fire growth patterns in diverse weather conditions and fuel types and to develop ore knowledge rules. The syste could be iproved with the addition of knowledge rules derived fro ore experts. The knowledge base should be regularly updated to include new advances in fire technology. Further, aside fro incorporating ore sophisticated fire behavior odels, other diensions of fire behavior and effects could be included. For exaple, post-frontal cobustion and soke production, holdover of fire activity in different fuel coplexes after precipitation, live fuel oisture variation, use of haronic ean to copute spread rates for spatial fuel ixtures and weather inputs would allow for a ore coprehensive siulation of fire growth and behavior. Bibliography [1] Rotherel, R.C., A atheatical odel for predicting fire spread in wildland fuels, [2] Rotherel, R.C., How to predict the spread and intensity of forest and range fires, 1983.