We observe a curious property of dual versus primal-dual path-following interior-point methods when applied to unbounded linear or conic programming problems in dual form. While primal-dual methods can be viewed as implicitly following a central path to detect primal infeasibility and dual unboundedness, dual methods can sometimes implicitly move away from the analytic center of the set of infe...

This report describes a necessary condition for feasibility of scheduling a set of sporadic hard-deadline tasks on a heterogeneous multiprocessor platform, which is also a sufficient condition if there is only a single processor. The key contribution is the characterization of the maximum, over all time intervals of a given length, of the amount of computation that must be completed to meet all...

We prove that the local search optimization problem TSP 2Opt |though not known to be PLS-complete|shares an important infeasibility property with other PLS-complete sets.

This paper combines two ingredients in order to get a rather surprising result on one of the most studied, elegant and powerful tools for solving convex feasibility problems, method alternating projections (MAP). Going back names such as Kaczmarz von Neumann, MAP has ability track pair points realizing minimum distance between given closed sets. Unfortunately, may suffer from arbitrarily slow c...

Suzuki et al. showed that properly oriented, right-stable, orthogonal, and oriented conditional term rewrite systems with extra variables in right-hand sides are confluent. We present our Isabelle/HOL formalization of this result, including two generalizations. On the one hand, we relax proper orientedness and orthogonality to extended proper orientedness and almost orthogonality modulo infeasi...

The super-efficiency (SE) model is identical to the standard model, except that the unit under evaluation is excluded from the reference set. This model has been used in ranking efficient units, identifying outliers, sensitivity and stability analysis, measuring productivity changes, and solving two-player games. Under the assumption of variable, non-increasing and non-decreasing returns to sca...

Software deobfuscation is a crucial activity in security analysis and especially, in malware analysis. While standard static and dynamic approaches suffer from well-known shortcomings, Dynamic Symbolic Execution (DSE) has recently been proposed has an interesting alternative, more robust than static analysis and more complete than dynamic analysis. Yet, DSE addresses certain kinds of questions ...