APPROXIMATION METHODS FOR PROBLEMS OF OPTIMAL CONTROL (MATHEMATICAL CONTROL THEORY); OPTIMIERUNGSMODELLE (OPERATIONS RESEARCH); OPTIMIZATION MODELS (OPERATIONS RESEARCH); NÄHERUNGSMETHODEN BEI PROBLEMEN DER OPTIMALEN REGELUNG (MATHEMATISCHE KONTROLLTHEORIE); TREES (GRAPH THEORY); ALGORITHMISCHE KOMPLEXITÄT (MATHEMATIK); ALGORITHMIC COMPLEXITY (MATHEMATICS); RISK AVERSION (OPERATIONS RESEARCH); GRAPHENMODELLE (GRAPHENTHEORIE); RISIKOAVERSION (OPERATIONS RESEARCH); GRAPH MODELS (GRAPH THEORY); BÄUME (GRAPHENTHEORIE)