Several database areas such as data exchange and integration share the problem of fixing database instance violations with respect to a set of constraints. The chase algorithm solves such violations by inserting tuples and setting the value of nulls. Unfortunately, the chase algorithm may not terminate and the problem of deciding whether the chase process terminates is undecidable. Recently the...

The H{\alpha} line is an important optical in solar observations containing the information from photosphere to chromosphere. To study mechanisms of eruptions and plasma dynamics lower atmosphere, Chinese Solar Explorer (CHASE) was launched into a Sun-synchronous orbit on October 14, 2021. scientific payload CHASE satellite Imaging Spectrograph (HIS). CHASE/HIS acquires, for first time, seeing-...

Chase-escape is a competitive growth process in which red particles spread to adjacent empty sites according rate-λ Poisson while being chased and consumed by blue rate-1 process. Given growing sequence of finite graphs, the critical rate λc largest value λ for fails reach positive fraction vertices with high probability. We provide conjecturally sharp lower bound an implicit upper on supercrit...