Showing papers in "Journal of Computer and System Sciences in 2019"

TL;DR: Theoretical models of programmable matter systems, consisting of n spherical modules kept together by magnetic or electrostatic forces and able to perform two minimal mechanical operations (movements), are studied to provide a type of distributed transformation.

TL;DR: Broadcasting in multiple access channels with dynamic packet arrivals and jamming is studied and upper bounds on the worst-case packet latency and the number of queued packets are given in relation to the parameters defining adversaries.

TL;DR: In this paper, structural sparsity in real-world networks is established, and several common network models regarding their structural sparseness are analyzed, including the Kleinberg and Barabasi-Albert models.

TL;DR: The flow model is new and differs from the “flows over time” model, also called “dynamic flows” in the literature, and it is shown that the problem of finding the maximum amount of flow that can pass from a source vertex to a sink vertex up to a given time is solvable in Polynomial time.

TL;DR: This paper characterize the set of digraphs that can be induced by two and three voters, respectively, and give sufficient conditions for larger numbers of voters and leverage the sufficient conditions to show that the winner determination problem of various well-known voting rules remains hard even when there is only a small constant number of voters.

TL;DR: It is proved that the HV-planarity testing problem is NP-complete even for graphs with vertex-degree at most three, which answers an open question posed by both Manuch et al.

TL;DR: This work combines the notion of determinism for regular expressions used in XML DTDs and XML Schema with the definition of a suitable automaton model, and a generalization of the Glushkov construction, to demonstrate that these deterministic regular expressions with back-references have desirable algorithmic properties.

TL;DR: An online bin packing algorithm with absolute competitive ratio 5/3, which is optimal is presented, and it is shown that this ratio is optimal in the real world.

TL;DR: A systematic parameterized complexity study of triangle enumeration, motivated by the fact that the worst-case running time is cubic, and provides both positive and negative results.

TL;DR: To find a better class for cost register automata, restrictions on copyless CRA are imposed, which ends successfully with a new robust computational model that is closed under reverse and other extensions.

TL;DR: This work considers Markov decision processes (MDPs) as generators of sequences of probability distributions over states, and establishes matching upper and lower complexity bounds of the problems.

TL;DR: This paper provides a framework for the synthesis of mediators that allows us to characterize the conditions for the mediator existence and correctness; and establish the applicability boundaries of the synthesis method.

TL;DR: It is shown that prioritized distortion is essentially equivalent to coarse scaling distortion via a general transformation, which is used to construct the near-minimum spanning tree with constant average distortion, and has many further implications to metric embeddings theory.

TL;DR: This work efficiently decides whether a word is a pseudo-repetition and find all the pseudo- repetitive factors of a word and approaches the problem of deciding whether there exists an anti-/morphism for which a word has been encoded under a certain morphism or antimorphism.

TL;DR: It is proved that Colouring is polynomial-time solvable for s = 4 and t ≤ 6, strengthening several known results and initiating a study into the boundedness of the clique-width of atoms (graphs with no clique cutset) of a hereditary graph class.

TL;DR: It is proved that for paths and trails the problem is NP-hard on undirected and directed planar graphs even if the maximum vertex degree or k ≥ 0 is constant, and for walks polynomial-time solvability is proved.

TL;DR: This work shows that MSE is W [ 1 ] -hard when parameterized by the treewidth of the input graph and the number k of shared edges combined, and that M SE does not admit a polynomial-size kernel with respect to p (unless NP ⊆ coNP / poly ).

TL;DR: A computational model that generically associates a tensor network to a graph or a hypergraph and then computes a value by generalized tensor contractions directed by its hyperedges, which generalizes the notion of recognizable series on strings and trees.

TL;DR: This paper performs a refined analysis of the tradeoff between the approximation factor and kernel size for the Dominating Set problem on d -degenerate graphs, and provides an interpolation of approximate kernels between the known 3 d -approximate kernel of constant size and 1-approximates kernel of size k O ( d 2 ) .

TL;DR: Algorithms for the circuit satisfiability problem of bounded depth circuits with AND, OR, NOT gates and a limited number of weighted symmetric gates are presented and average- case lower bounds and compression algorithms for such circuits and worst-case lower bounds for majority votes of such circuits are shown.

TL;DR: In this article, it was shown that shifted combinatorial optimization over MSO definable sets is in XP with respect to the MSO formula and the treewidth (or more generally clique width) of the input graph, and is W[1]-hard even under further severe restrictions.

TL;DR: Computational complexity bounds for various classes of functions computed by cost register automata are given.

TL;DR: It is shown that the most general case of the (unweighted) problem where one would like to preserve ρ-vertex connectivity for any ρ is (non-uniformly) FPT parameterized by k and ρ and the unweighted case even admits a randomized polynomial kernel.

TL;DR: Several insertion operations are studied applied to languages accepted by one-way and two-way deterministic reversal-bounded multicounter machines, investigating the question of whether the resulting languages can always be accepted by deterministic machines with the same number of input-turns.

TL;DR: The regularity properties (uniform recurrence, uniform frequencies, topological entropy) of quasiperiodicity with multi-scale quas Piperiodicity are compared, and each of them is compared with its one-dimensional counterpart.

TL;DR: This work develops a unifying approach to declarative entity linking by introducing the notion of an entity-linking framework and an accompanying notion of the certain links in such a framework, and investigates the relative expressive power of several entity- linking frameworks.

TL;DR: It is proved that given an arbitrary fault-free vertex r in an m -dimensional restricted hypercube-like graph with a set F of faults and d positive integers, there exists a d -starlike tree rooted at r, each of whose subtrees forms a fault- free path on l i vertices.

TL;DR: In this article, the notion of finite-state independence of normal words was defined and characterized in three different ways, using three different kinds of asynchronous deterministic finite automata with two input tapes containing infinite words.

TL;DR: This work considers three variants of rendezvous differentiated by the level of restricted maneuverability of robots in both synchronous and asynchronous models of computation and proposes the relevant algorithms and discusses their efficiency.

TL;DR: The precise asymptotic value of the rotor-router cover time for all values of $k$ for degree-restricted expanders, random graphs, and constant-dimensional tori is determined, except for values of$k$ much larger than $n$.