New Method for Measuring Diagnosis Indexes Based on Concept Lattices in Dam Health Diagnosis

Abstract

With multi-layers and multi-indexes, dam health diagnosis is an important way to diagnose the structural safety and health operation of dams. This study focuses on the measurement of diagnosis indexes in dam health diagnosis. The existing methods of constructing diagnosis indexes are mainly based on the subjective judgment of expert knowledge, and lack of consideration of the internal mapping relationship between diagnosis indexes and dam health levels. Therefore, it is necessary to introduce new theories and new methods to study the objective measurement of diagnostic indexes in combination with the characteristics of dam health diagnosis. Based on the Dempster-Shafer (D-S) evidence theory, a new concept lattices-based model for building basic probability assignments (BPAs) is proposed in this study. First, concept lattices under hesitant fuzzy linguistic term sets (HFLTSs) were established to formalize the qualitative and quantitative expression of expert knowledge. Then we defined a new distance of HFLTSs, named NWD. NWD is strict in mathematical definition and considers the non-overlapping HFLTSs. Based on NWD, the weight of the monitoring point for each health level was obtained through similarity analysis and finally transformed into the corresponding BPA. An engineering project demonstrated that the BPAs developed in this study could adequately describe the attributes of diagnosis indexes, forming reliable bases for the comprehensive diagnosis fusion. Simultaneously, the proposed method of building the BPA can significantly improve assignment efficiency, which can shed light on the development of dam operation behavior modelling.INDEX TERMS Basic probability assignment, concept lattice, dam health diagnosis, diagnosis index, D-S evidence theory.