The Experts below are selected from a list of 17961 Experts worldwide ranked by ideXlab platform
Bernhard Wess - One of the best experts on this subject based on the ideXlab platform.
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list coloring of Interval Graphs with application to register assignment for heterogeneous register set architectures
Signal Processing, 2003Co-Authors: T. Zeitlhofer, Bernhard WessAbstract:This article focuses on register assignment problems for heterogeneous register-set VLIW-DSP architectures. It is assumed that an instruction schedule has already been generated. The register assignment problem is equivalent to the well-known coloring of an interference Graph. Typically, machine-related constraints are mapped onto the structure of the interference Graph. Thereby favorable characteristics with regard to coloring, the Interval Graph properties, get lost. In contrast, we present an approach that does not change the structure of the interference Graph. Constraints implied by heterogeneous architectures are mapped to a specific coloring problem that is known as list-coloring. Exploiting the Interval Graph properties of the interference Graph, we derive a list-coloring algorithm that allows us to generate optimum solutions even for large basic blocks. The proposed technique can also be applied to similar resource assignment problems like functional unit assignment.
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ISCAS (3) - Optimum register assignment for heterogeneous register-set architectures
Proceedings of the 2003 International Symposium on Circuits and Systems 2003. ISCAS '03., 2003Co-Authors: T. Zeitlhofer, Bernhard WessAbstract:This paper focuses on the register assignment problem for basic blocks assuming a given instruction schedule. This is equivalent to the well-known coloring of an interference Graph which satisfies the Interval Graph properties if no other constraints are considered. For a set of equivalent colors (homogeneous registers), an Interval Graph is colorable with linear complexity. In contrast, however, we assume a heterogeneous register-set as often found in general purpose digital signal processors. In this case, register assignment corresponds to a list-coloring problem which is NP-complete even for Interval Graphs. Topically, heuristics have to be applied. However, we present a search space pruning technique based on a Graph decomposition into maximum cliques that allows us to find proper colorings if there are any. Our optimum technique is applicable even to large Graphs since the maximum number of colorings that have to be investigated just depend on the maximum clique size.
Saikat Pal - One of the best experts on this subject based on the ideXlab platform.
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an o n m o n m time algorithm for computing a minimum semitotal dominating set in an Interval Graph
Journal of Applied Mathematics and Computing, 2020Co-Authors: Dinabandhu Pradhan, Saikat PalAbstract:Let $$G=(V,E)$$ be a Graph without isolated vertices. A set $$D\subseteq V$$ is said to be a dominating set of G if for every vertex $$v\in V\setminus D$$ , there exists a vertex $$u\in D$$ such that $$uv\in E$$ . A set $$D\subseteq V$$ is called a semitotal dominating set of G if D is a dominating set and every vertex in D is within distance 2 from another vertex of D. For a given Graph G, the semitotal domination problem is to find a semitotal dominating set of G with minimum cardinality. The decision version of the semitotal domination problem is shown to be NP-complete for chordal Graphs and bipartite Graphs. Henning and Pandey (Theor Comput Sci 766:46–57, 2019) proposed an $$O(n^2)$$ time algorithm for computing a minimum semitotal dominating set in Interval Graphs. In this paper, we show that for a given Interval Graph $$G=(V,E)$$ , a minimum semitotal dominating set of G can be computed in $$O(n+m)$$ time, where $$n=|V|$$ and $$m=|E|$$ . This improves the complexity of the semitotal domination problem for Interval Graphs from $$O(n^2)$$ to $$O(n+m)$$ .
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An $$O(n+m)$$ O ( n + m ) time algorithm for computing a minimum semitotal dominating set in an Interval Graph
Journal of Applied Mathematics and Computing, 2020Co-Authors: Dinabandhu Pradhan, Saikat PalAbstract:Let $$G=(V,E)$$ G = ( V , E ) be a Graph without isolated vertices. A set $$D\subseteq V$$ D ⊆ V is said to be a dominating set of G if for every vertex $$v\in V\setminus D$$ v ∈ V \ D , there exists a vertex $$u\in D$$ u ∈ D such that $$uv\in E$$ u v ∈ E . A set $$D\subseteq V$$ D ⊆ V is called a semitotal dominating set of G if D is a dominating set and every vertex in D is within distance 2 from another vertex of D . For a given Graph G , the semitotal domination problem is to find a semitotal dominating set of G with minimum cardinality. The decision version of the semitotal domination problem is shown to be NP -complete for chordal Graphs and bipartite Graphs. Henning and Pandey (Theor Comput Sci 766:46–57, 2019) proposed an $$O(n^2)$$ O ( n 2 ) time algorithm for computing a minimum semitotal dominating set in Interval Graphs. In this paper, we show that for a given Interval Graph $$G=(V,E)$$ G = ( V , E ) , a minimum semitotal dominating set of G can be computed in $$O(n+m)$$ O ( n + m ) time, where $$n=|V|$$ n = | V | and $$m=|E|$$ m = | E | . This improves the complexity of the semitotal domination problem for Interval Graphs from $$O(n^2)$$ O ( n 2 ) to $$O(n+m)$$ O ( n + m ) .
T. Zeitlhofer - One of the best experts on this subject based on the ideXlab platform.
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list coloring of Interval Graphs with application to register assignment for heterogeneous register set architectures
Signal Processing, 2003Co-Authors: T. Zeitlhofer, Bernhard WessAbstract:This article focuses on register assignment problems for heterogeneous register-set VLIW-DSP architectures. It is assumed that an instruction schedule has already been generated. The register assignment problem is equivalent to the well-known coloring of an interference Graph. Typically, machine-related constraints are mapped onto the structure of the interference Graph. Thereby favorable characteristics with regard to coloring, the Interval Graph properties, get lost. In contrast, we present an approach that does not change the structure of the interference Graph. Constraints implied by heterogeneous architectures are mapped to a specific coloring problem that is known as list-coloring. Exploiting the Interval Graph properties of the interference Graph, we derive a list-coloring algorithm that allows us to generate optimum solutions even for large basic blocks. The proposed technique can also be applied to similar resource assignment problems like functional unit assignment.
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ISCAS (3) - Optimum register assignment for heterogeneous register-set architectures
Proceedings of the 2003 International Symposium on Circuits and Systems 2003. ISCAS '03., 2003Co-Authors: T. Zeitlhofer, Bernhard WessAbstract:This paper focuses on the register assignment problem for basic blocks assuming a given instruction schedule. This is equivalent to the well-known coloring of an interference Graph which satisfies the Interval Graph properties if no other constraints are considered. For a set of equivalent colors (homogeneous registers), an Interval Graph is colorable with linear complexity. In contrast, however, we assume a heterogeneous register-set as often found in general purpose digital signal processors. In this case, register assignment corresponds to a list-coloring problem which is NP-complete even for Interval Graphs. Topically, heuristics have to be applied. However, we present a search space pruning technique based on a Graph decomposition into maximum cliques that allows us to find proper colorings if there are any. Our optimum technique is applicable even to large Graphs since the maximum number of colorings that have to be investigated just depend on the maximum clique size.
Dinabandhu Pradhan - One of the best experts on this subject based on the ideXlab platform.
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an o n m o n m time algorithm for computing a minimum semitotal dominating set in an Interval Graph
Journal of Applied Mathematics and Computing, 2020Co-Authors: Dinabandhu Pradhan, Saikat PalAbstract:Let $$G=(V,E)$$ be a Graph without isolated vertices. A set $$D\subseteq V$$ is said to be a dominating set of G if for every vertex $$v\in V\setminus D$$ , there exists a vertex $$u\in D$$ such that $$uv\in E$$ . A set $$D\subseteq V$$ is called a semitotal dominating set of G if D is a dominating set and every vertex in D is within distance 2 from another vertex of D. For a given Graph G, the semitotal domination problem is to find a semitotal dominating set of G with minimum cardinality. The decision version of the semitotal domination problem is shown to be NP-complete for chordal Graphs and bipartite Graphs. Henning and Pandey (Theor Comput Sci 766:46–57, 2019) proposed an $$O(n^2)$$ time algorithm for computing a minimum semitotal dominating set in Interval Graphs. In this paper, we show that for a given Interval Graph $$G=(V,E)$$ , a minimum semitotal dominating set of G can be computed in $$O(n+m)$$ time, where $$n=|V|$$ and $$m=|E|$$ . This improves the complexity of the semitotal domination problem for Interval Graphs from $$O(n^2)$$ to $$O(n+m)$$ .
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An $$O(n+m)$$ O ( n + m ) time algorithm for computing a minimum semitotal dominating set in an Interval Graph
Journal of Applied Mathematics and Computing, 2020Co-Authors: Dinabandhu Pradhan, Saikat PalAbstract:Let $$G=(V,E)$$ G = ( V , E ) be a Graph without isolated vertices. A set $$D\subseteq V$$ D ⊆ V is said to be a dominating set of G if for every vertex $$v\in V\setminus D$$ v ∈ V \ D , there exists a vertex $$u\in D$$ u ∈ D such that $$uv\in E$$ u v ∈ E . A set $$D\subseteq V$$ D ⊆ V is called a semitotal dominating set of G if D is a dominating set and every vertex in D is within distance 2 from another vertex of D . For a given Graph G , the semitotal domination problem is to find a semitotal dominating set of G with minimum cardinality. The decision version of the semitotal domination problem is shown to be NP -complete for chordal Graphs and bipartite Graphs. Henning and Pandey (Theor Comput Sci 766:46–57, 2019) proposed an $$O(n^2)$$ O ( n 2 ) time algorithm for computing a minimum semitotal dominating set in Interval Graphs. In this paper, we show that for a given Interval Graph $$G=(V,E)$$ G = ( V , E ) , a minimum semitotal dominating set of G can be computed in $$O(n+m)$$ O ( n + m ) time, where $$n=|V|$$ n = | V | and $$m=|E|$$ m = | E | . This improves the complexity of the semitotal domination problem for Interval Graphs from $$O(n^2)$$ O ( n 2 ) to $$O(n+m)$$ O ( n + m ) .
Minsheng Lin - One of the best experts on this subject based on the ideXlab platform.
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linear time algorithms for counting the number of minimal vertex covers with minimum maximum size in an Interval Graph
Information Processing Letters, 2008Co-Authors: Minsheng Lin, Yungjui ChenAbstract:This paper presents efficient algorithms for an Interval Graph. These are (1) an algorithm for counting the number of minimum vertex covers, and (2) an algorithm for counting the number of maximum minimal vertex covers.
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fast and simple algorithms to count the number of vertex covers in an Interval Graph
Information Processing Letters, 2007Co-Authors: Minsheng LinAbstract:This study provides the following fast and simple algorithms for an Interval Graph: (1) an algorithm for counting the number of vertex covers, and (2) an algorithm for counting the number of minimal vertex covers.
