arXiv subjects

G. W. Greenwood

Publications and source records attributed to G. W. Greenwood.

3 recordsLinked to original sources

arXiv2002

How to Evolve Safe Control Strategies

Autonomous space vehicles need adaptive control strategies that can accommodate unanticipated environmental conditions. The evaluation of new strategies can often be done only by actually trying them out in the real physical environment. Consequently, a candidate control strategy must be deemed safe--i.e., it won't damage any systems--prior to being tested online. How to do this efficiently has been a challenging problem. We propose using evolutionary programming in conjunction with a formal verification technique (called model checking) to evolve candidate control strategies that are guaranteed to be safe for implementation and evaluation.

math.OC↗

arXiv2002

Revisiting the Complexity of Finding Globally Minimum Energy Configurations in Atomic Clusters

It has previously been proven that finding the globally minimum energy configuration of an atomic cluster belongs in the class of NP-hard problems. However, this proof is limited only to homonuclear clusters. This paper presents a new proof which shows finding minimum energy configurations for heteronuclear clusters is also NP-hard.

physics.atm-clus↗

arXiv2000

Finding Solutions to NP Problems: Philosophical Difference Between Quantum and Evolutionary Search Algorithms

There is no known polynomial-time algorithm that can solve an NP problem. Evolutionary search has been shown to be a viable method of finding acceptable solutions within a reasonable time period. Recently quantum computers have surfaced as another alternative method. But these two methods use radically different philosophies for solving NP problems even though both search methods are non-deterministic. This paper uses instances of {\bf SAT}, {\bf 3SAT} and {\bf TSP} to describe how these two methods differ in their approach to solving NP problems.

quant-ph↗