A growing literature has investigated the role that formal and informal economic institutions play for autocratic survival. However, this has, so far, ignored a type of institution grown in importance among both democracies non-democracies recent decades, namely, national fiscal rules. In article, we argue rules can affect survival but effect is time-dependent. The introduction stricter framewo...

The geometry of alluvial river channels both controls and adjusts to the flow water sediment within them. This feedback between form modulates flood risk, impacts climate land-use change. Considering widely varying hydro-climates, supply, geology vegetation, it is surprising that rivers follow remarkably consistent hydraulic scaling relations. In this Perspective, we explore factors governing c...

The operation of chemical processes often requires respecting constraints on manipulated inputs and process states. Input constraints typically reflect limits on the capacity of control actuators, such as valves or pumps, whereas state constraints represent desirable ranges of operation for process variables, such as temperatures or concentrations. Constraints, however, limit the set of initial...

The maximum power transfer across critical corridors or interfaces is limited by various system constraints such as thermal, voltage, and stability limits. In an open transmission access environment, these constraints would be deeply influenced by the interactions among the path flows in different control areas. In particular, small signal stability, commonly in the form of low frequency oscill...

We present a powerful heuristic that detects implicit equality constraints that may occur in the specification of systems of constraints in order to find Lyapunov-based certificates of stability for hybrid systems. A hybrid system is a fusion of systems exhibiting discrete-time as well as continuous-time behavior, e.g. embedded systems within a physical environment. Stability is a property whic...

Optimal power flow is the most complicated economical problem in power system operation. This is due to the nonlinearity of load flow equations and constraints on voltage, thermal limits and angle and voltage stability. The objective of this problem is to distribute system loads among generators with minimum cost while achieving all equality and inequality constraints. Nowadays, meta heuristic ...