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- R E Nickel, J S Gallenstein
- Developmental medicine and child neurology
- 1987

The development of nine infants with enlarged subarachnoid spaces identified by specific CT-scan criteria was prospectively followed to two to three years of age. Infants with intracranial hemorrhage, CNS anomaly, microcephaly or other factors of potentially major negative impact on their development were excluded. All study infants had normal or only… (More)

- Robert Nickel, Winfried Hochstättler
- Contributions to Discrete Mathematics
- 2007

Recently Hochstättler and Nešetřil introduced the flow lattice of an oriented matroid as generalization of the lattice of all integer flows of a digraph or more general a regular matroid. This lattice is defined as the integer hull of the characteristic vectors of signed circuits. Here, we characterize the flow lattice of oriented matroids that are uniform… (More)

- Winfried Hochstättler, Hui Jin, Robert Nickel
- AAIM
- 2006

We derive a polynomial time algorithm to compute a stable solution in a mixed matching market from an auction procedure as presented by Eriksson and Karlander [5]. As a special case we derive an O(nm) algorithm for bipartite matching that does not seem to have appeared in the literature yet.

- Winfried Hochstättler, Robert Nickel, Britta Peis
- Electronic Notes in Discrete Mathematics
- 2006

1 Motivation Signed graphs have been studied a lot during the last two decades. We address the vertex disjoint negative cycle packing problem posed by Zaslavsky [7, Problem II.A.1a]. Our aim is to find two vertex disjoint negative cycles in reasonable time which generalizes the problem of finding two vertex disjoint odd cycles in a graph. In the first stage… (More)

- R E Nickel, C A Renken, J S Gallenstein
- Developmental medicine and child neurology
- 1989

The authors describe the Infant Motor Screen, which is a brief evaluation of the quality of motor patterns of preterm infants from four to 16 months of age. It was developed for use with an assessment of motor milestones as part of a developmental screening program for high-risk infants. 111 infants were tested at four months and 58 at eight months. The… (More)

- Winfried Hochstättler, Robert Nickel
- J. Comb. Theory, Ser. B
- 2008

- Winfried Hochstättler, Robert Nickel
- Eur. J. Comb.
- 2011

- Thomas Epping, Winfried Hochstättler, Robert Nickel, Peter Oertel
- Intelligente Systeme zur Entscheidungsunterst…
- 2008

We describe a new solution approach for order sequencing which reflects the build-to-order strategy of the European automobile industry. Therefore, it has to cope with a daily changing variety of customer orders. Each order consists of a set of commodities which are implemented while the order sequence passes through a body shop, a paint shop, and an… (More)

A family C of signed subsets is the set of signed circuits of an oriented matroid O if it satisfies the circuit axioms. By forgetting the signs we get the underlying matroid.

1 Overview Let O be an oriented matroid on a ground set E with n elements and C its set of signed circuits. We identify a circuit C ∈ C with its signed characteristic vector χ C ∈ {0, ±1} n. In this paper we will discuss some questions concerning the integer lattice of C denoted by L(C) which are quite natural in the context of integer lattices: 1. What is… (More)