Robert Engström

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BACKGROUND Inability to express emotions is common in patients with long-lasting somatic symptoms associated with incapacitation and impaired quality of life. One method for treating this inability is art psychotherapy. In this study the typical course in such treatments is described. Patients were followed longitudinally before therapy and every 4th to 6th(More)
A graph homomorphism is a vertex map which carries edges from a source graph to edges in a target graph. The instances of the Weighted Maximum H-Colourable Subgraph problem (MAX H-COL) are edge-weighted graphs G and the objective is to find a subgraph of G that has maximal total edge weight, under the condition that the subgraph has a homomorphism to H;(More)
The instances of the Weighted Maximum H-Colourable Subgraph problem (Max H-Col) are edge-weighted graphs G and the objective is to find a subgraph of G that has maximal total edge weight, under the condition that the subgraph has a homomorphism to H; note that for H = K k this problem is equivalent to Max k-cut. Färnqvist et al. have introduced a parameter(More)
We introduce a binary parameter on optimisation problems called separation. The parameter is used to relate the approximation ratios of different optimisation problems; in other words, we can convert approximability (and non-approximability) result for one problem into (non)-approximability results for other problems. Our main application is the problem(More)
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