Homotopy classification of homogeneous projections in the corona algebra   of a non-simple C*-algebra
  In this paper we consider certain proejctions in the corona algebra of $C(X)\otimes B$ associated to $(p_0, p_1, \dots, p_n)$ where $p_i: X_i \to \mt_s$ a continuous projection valued section to the multiplier algebra of a stable $C\sp*$-algebra $B$ for each i. Here $X_i$'s are closed intervals given by a partition $\{x_1, \dots, x_n\}$ on the interior of $X$ and adjacent sections differ by compacts at each partition point. Assuming a kind of homogeneity on the projection we characterize when two such projections are homotopy equivalent. 
Hyun Ho Lee
math.OA