DNP enhancement, paramagnet-induced quenching/depolarization and build-up times are studied in a heterogeneous catalyst between 30 100 K. He-cooled MAS at K provides up to 100-fold better time performance than N2-cooled 90

A transversal of a hypergraph is a set of vertices meeting all the hyperedges. A k-fold transversal of a hypergraph is a set of vertices such that every hyperedge has at least k elements of. In this paper, we prove that a k-fold transversal of a balanced hypergraph can be expressed as a union of k pairwise disjoint transversals and such partition can be obtained in polynomial time. We give an N...

The k-fold cross-validation is commonly used to evaluate the effectiveness of SVMs with the selected hyper-parameters. It is known that the SVM k-fold cross-validation is expensive, since it requires training k SVMs. However, little work has explored reusing the h SVM for training the (h+ 1) SVM for improving the efficiency of k-fold cross-validation. In this paper, we propose three algorithms ...

Fix integers k and t . The t–fold center of mass arrangement M(t, k) for integers t with k ≥ t ≥ 1 is defined as the subspace of the k–fold product Ck given by ordered k–tuples of points (x1, . . . , xk) such that the centroids of any set of t elements in the underlying set {x1, . . . , xk} σt(xi1 , xi2 , . . . , xit ) = (1/t)(xi1 + xi2 + · · ·+ xit ) are distinct for all distinct subsets {xi1 ...

Higher-Order Fixpoint Logic (HFL) is a hybrid of the simply typed λ-calculus and the modal μ-calculus. This makes it a highly expressive temporal logic that is capable of expressing various interesting correctness properties of programs that are not expressible in the modal μ-calculus. This paper provides complexity results for its model checking problem. In particular, we consider those fragme...

In this paper we study a 3-fold X ⊂ P that is a complete intersection of two hypersurfaces Fn and Gk of degree n and k respectively such that n ≥ k and the only singularities of X are ordinary double points. The 3-fold X is called factorial if every surface in X is cut by a hypersurface in P. The factoriality of the 3-fold X is equivalent to a global topological condition rkH4(X,Z) = 1, which f...

We prove that octants are cover-decomposable into multiple coverings, i.e., for any k there is an m(k) such that any m(k)-fold covering of any subset of the space with a nite number of translates of a given octant can be decomposed into k coverings. As a corollary, we obtain that any m(k)-fold covering of any subset of the plane with a nite number of homothetic copies of a given triangle can be...

We consider the efficient deterministic solution of elliptic boundary value problems with random diffusion matrix. Assuming random perturbations with known k moments, we derive, to leading order in the random perturbation’s amplitude, deterministic equations for k moments of the random solution. The solution’s k-th moment satisfies a k-fold tensor product boundary value problem on the k-fold pr...