HR: 1340h
AN: H33D-0498    [Abstracts]
TI: Restoring Consistency In Subjective Information For Groundwater Driven Health Risk Assessment
AU: * Ozbek, M M
EM: ozbek@emba.uvm.edu
AF: Department of Civil and Environmental Engineering, University of Vermont 213 Votey Building, Burlington, VT 05405 United States
AU: Pinder, G F
EM: pinder@emba.uvm.edu
AF: Department of Civil and Environmental Engineering, University of Vermont 213 Votey Building, Burlington, VT 05405 United States
AB: In an earlier work (Ozbek and Pinder, 2003), we constructed a fuzzy rule-based knowledge base that uses subjective expert opinion to calculate risk-based design constraints (i.e., dose and pattern of exposure) to sustain the groundwater-driven individual health risk at a desired level. Ideally, our system must be capable to produce for any individual a meaningful risk result or for any given risk a meaningful design constraint, in the sense that the result is neither the empty set nor the whole domain of the variable of interest. Otherwise we consider our system as inconsistent. We present a method based on fuzzy similarity relations to restore consistency in our implicative fuzzy rule based system used for the risk-based groundwater remediation design problem. Both a global and a local approach are considered. Even though straightforward and computationally less demanding, the global approach can affect pieces of knowledge negatively by inducing unwarranted imprecision into the knowledge base. On the other hand, the local approach, given a family of parameterized similarity relations, determines a parameter for each inference such that consistent results are computed which may not be feasible in real time applications of our knowledge base. Several scenarios are considered for comparing the two approaches that suggest that for specific applications one or several approaches ranging from a completely global to a completely local one will be more suitable than others while calculating the design constraints.
DE: 6309 Decision making under uncertainty
DE: 6615 Legislation and regulation
DE: 1803 Anthropogenic effects
DE: 1836 Hydrologic budget (1655)
DE: 1600 GLOBAL CHANGE (New category)
SC: Hydrology [H]
MN: 2004 AGU Fall Meeting