Classify the hard

We prove the Minimum Vertex Cover problem to be NP-hard to approximate to within a factor of 1.3606, extending on previous PCP and hardness of approximation technique. To that end, one needs to develop a new proof framework, and to borrow and extend ideas from several fields. 1. Introduction The basic purpose of computational complexity theory is to classify computational problems according to the amount of resources required to solve them. In particular, the most basic task is to classify computational problems to those that are efficiently solvable and those that are not. ...

48p noel_noel 17-01-2013 60 6   Download

Catalytic oxidation of organic compounds is an extremely important field of chemistry, spanning the range from biological oxidations to large scale industrial production of commodity chemicals. However, many of these transformations can hardly be classified as organometallic reactions, since the catalysts (often simple metal salts) and the intermediates can be rather regarded as coordination complexes than organometallic compounds.

7p boyminsk 10-06-2010 103 18   Download