Mark Cieliebak

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Consider a set of n > 2 simple autonomous mobile robots (decentralized, asynchronous, no common coordinate system, no identities, no central coordination, no direct communication, no memory of the past, deterministic) moving freely in the plane and able to sense the positions of the other robots. We study the primitive task of gathering them at a point not(More)
We study the Gathering Problem, where we want to gather a set of n autonomous mobile robots at a point in the plane. This point is not fixed in advance. The robots are very weak, in the sense that they have no common coordinate system, no identities, no central coordination, no means of direct communication, and no synchronization. Each robot can only sense(More)
We study the problem of coordinating a set of autonomous mobile robots that can freely move in a two-dimensional plane; in particular, we want them to gather at a point not fixed in advance (GATHERING PROBLEM). We introduce a model of weak robots (decentralized, asynchronous, no common knowledge, no identities, no central coordination, no direct(More)
Consider a set of n > 2 identical mobile computational entities in the plane, called robots, operating in Look-Compute-Move cycles, without any means of direct communication. The Gathering Problem is the primitive task of all entities gathering in finite time at a point not fixed in advance, without any external control. The problem has been extensively(More)
The problem to find the coordinates of n points on a line such that the pairwise distances of the points form a given multi-set of n 2 distances is known as Partial Digest problem, which occurs for instance in DNA physical mapping and de novo sequencing of proteins. Although Partial Digest was – as a combinatorial problem – already proposed in the 1930’s,(More)
A set of n points in the plane is in equiangular configuration if there exist a center and an ordering of the points such that the angle of each two adjacent points w.r.t. the center is 360 ◦ n , i.e., if all angles between adjacent points are equal. We show that there is at most one center of equiangularity, and we give a linear time algorithm that decides(More)
We revisit the double digest problem, which occurs in sequencing of large DNA strings and consists of reconstructing the relative positions of cut sites from two different enzymes: we rst show that double digest is strongly NP-complete, improving previous results that only showed weak NP-completeness. Even the (experimentally more meaningful) variation in(More)
The Equal Sum Subsets problem, where we are given a set of positive integers and we ask for two nonempty disjoint subsets such that their elements add up to the same total, is known to be NP-hard. In this paper we give (pseudo-)polynomial algorithms and/or (strong) NP-hardness proofs for several natural variations of Equal Sum Subsets. Among others we(More)
We present AUDENS, a new platform-independent open source tool for automated de novo sequencing of peptides from MS/MS data. We implemented a dynamic programming algorithm and combined it with a flexible preprocessing module which is designed to distinguish between signal and other peaks. By applying a user-defined set of heuristics, AUDENS screens through(More)