“…Different from a single interval, e.g., [a, b], with deterministic bounds a and b, a dual interval [[a, c], [d, b]] carries interval bounds [a, c] and [d, b], representing the uncertainties in lower and upper bounds of a single interval. Recently, a number of similar studies were reported on dealing with uncertainties in the boundaries of a single interval (Guo et al, 2008;He et al, 2008He et al, , 2009Lu et al, 2008). Nie et al (2007) introduced a concept of fuzzy-boundary interval (an interval with fuzzy-valued lower and upper bounds) and then developed an interval-parameter fuzzy robust programming (IFRP) model.…”