Super Line Graph Research Papers (original) (raw)

Tractor is used as a main source of power in developing countries. In order to reduce the cost of production, knowledge of today’s complicated tools is essential. In this research, a threepoint hitch dynamometer system was fabricated for... more

Tractor is used as a main source of power in developing countries. In order to reduce the cost of production, knowledge of today’s complicated tools is essential. In this research, a threepoint hitch dynamometer system was fabricated for the category 0 & I tractors with the weight of 49 kg and the chassis is in a reversed U-shaped frame which allows the use of PTO at the same time. With the strain gages installed on the three sensing pins and developed five Wheatstone bridges in such a manner that, the draft forces in each link in addition to vertical forces on the lower links are measured. The dynamometer system consists of three parts including: the chassis, sensing components, and recording system. The recording system consisted of a Campbell data logger (CR10X) with a notebook computer. The dynamometer system was calibrated and several field tests were conducted to measure the force required to pull the different mounted plows. The field tests showed that the dynamometer worked ...

The Wiener index W is the sum of distances between all pairs of vertices of a (connected) graph. The paper outlines the results known for W of trees: methods for computation of W and combinatorial expressions for W for various classes of... more

The Wiener index W is the sum of distances between all pairs of vertices of a (connected) graph. The paper outlines the results known for W of trees: methods for computation of W and combinatorial expressions for W for various classes of trees, the isomorphism–discriminating power of W, connections between W and the center and centroid of a tree, as

A subset of vertices in a graph is called a dissociation set if it induces a subgraph with a vertex degree of at most 1. The maximum dissociation set problem, i.e., the problem of finding a dissociation set of maximum size in a given... more

A subset of vertices in a graph is called a dissociation set if it induces a subgraph with a vertex degree of at most 1. The maximum dissociation set problem, i.e., the problem of finding a dissociation set of maximum size in a given graph is known to be NP-hard for bipartite graphs. We show that the maximum dissociation set

For a graph G=(V, E) its line graph L(G) has the node set E and two nodes of L(G) are adjacent if the corresponding edges of G have a common endpoint. The problem of finding G for a given L was already optimally solved by Lehot[7] and... more

For a graph G=(V, E) its line graph L(G) has the node set E and two nodes of L(G) are adjacent if the corresponding edges of G have a common endpoint. The problem of finding G for a given L was already optimally solved by Lehot[7] and Roussopoulos[11]. Here we present a new dynamic solution to this problem, where we can add or delete a node v in L(G) in time proportional to the size of its adjacency list.

Self-dual 1-configurations (nd)1(n_d)_1(nd)1 possess their Menger graph mathcalY\mathcal YmathcalY most K4K_4K4-separated among connected self-dual configurations (nd)(n_d)(nd). Such mathcalY\mathcal YmathcalY is most symmetric if KdK_dKd-ultrahomogeneous. In this work, such a... more

Self-dual 1-configurations (nd)1(n_d)_1(nd)1 possess their Menger graph mathcalY\mathcal YmathcalY most K4K_4K4-separated among connected self-dual configurations (nd)(n_d)(nd). Such mathcalY\mathcal YmathcalY is most symmetric if KdK_dKd-ultrahomogeneous. In this work, such a mathcalY\mathcal YmathcalY is presented for (n,d)=(102,4)(n,d)=(102,4)(n,d)=(102,4) and shown to relate nnn copies of the cuboctahedral graph L(Q3)L(Q_3)L(Q3) to the nnn copies of KdK_dKd; these are shown to share each copy of K_3K_3K3 exactly with two copies of L(Q3)L(Q_3)L(Q_3).

In this work we introduce an algorithm to approximate the external shape of an irregular polyline containing some cycles and interlacements. The output consists of a counterclockwise closed walk still containing only some cycles that,... more

In this work we introduce an algorithm to approximate the external shape of an irregular polyline containing some cycles and interlacements. The output consists of a counterclockwise closed walk still containing only some cycles that, with the addition of one more step, can be “opened” in a suitable way to produce a Hamiltonian circuit. Moreover, the time cost of the algorithm is explained and the data structures introduced are described. The proposed algorithm applies to the polyline described by all the input data points as well as the polyline returned using a simplification/reduction method. We also describe how the entire algorithm, or some part of it, can be applied to the output of some well-known reduction methods to solve particular problems which may arise. We carried out a first implementation of the algorithm in MATLAB for its capability to provide both numerical and graphical tools within the same programming language as well as specific features offered by its Toolboxes and by the community of its users. We shall refer to it when reporting some of the results.

The Central Valley, California, R-EMAP project assessed the effects of highly modified, agriculturally dominated landuse on the aquatic resources of the lower portion of the Central Valley watersheds. The focus of this paper is to assess... more

The Central Valley, California, R-EMAP project assessed the effects of highly modified, agriculturally dominated landuse on the aquatic resources of the lower portion of the Central Valley watersheds. The focus of this paper is to assess the utility of the EMAP design and the River Reach File version 3 (RF3) 1:100,000 scale Digital Line Graph (DLG) as a sampling frame.

Abstract. Given a vertex-weighted graph G = (V, E; w), w(v) � 0 for any v 2 V , we consider a weighted version of the coloring problem which consists in finding a partition S = (S1, . . . , Sk) of the vertex set V of G into stable sets... more

Abstract. Given a vertex-weighted graph G = (V, E; w), w(v) � 0 for any v 2 V , we consider a weighted version of the coloring problem which consists in finding a partition S = (S1, . . . , Sk) of the vertex set V of G into stable sets and minimizing P, i=1 w(Si) where the weight of S is defined as max{w(v) : v 2 S}. In this paper, we keep on with the investigation of the complexity and the approximability of this problem by mainly answering one of the questions raised by D. J. Guan and X. Zhu (”A Coloring Problem for Weighted Graphs”, Inf. Process. Lett. 61(2):77-81 1997). Keywords: Approximation algorithm; NP-complete problems; weighted

For an arbitrary simple graph G and a positive integer r, the super line multigraph of index r of G, denoted Mr(G), has for vertices all the r-subsets of edges. Two vertices S and T are joined by as many edges as pairs of distinct edges s... more

For an arbitrary simple graph G and a positive integer r, the super line multigraph of index r of G, denoted Mr(G), has for vertices all the r-subsets of edges. Two vertices S and T are joined by as many edges as pairs of distinct edges s in S and t in T share a common vertex in G. We present spectral properties of Mr(G) and particularly, if G is a regular graph, we calculate all the eigenvalues of Mr(G) and their multiplicities in terms of those of G.

We also treat the eigenvalues and energy of the line graphs of signed graphs, and the Laplacian eigenvalues and Laplacian energy in the regular case, with application to the line graphs of signed grids that are Cartesian products and to... more

We also treat the eigenvalues and energy of the line graphs of signed graphs, and the Laplacian eigenvalues and Laplacian energy in the regular case, with application to the line graphs of signed grids that are Cartesian products and to the line graphs of all-positive and all-negative complete graphs.

The line graphs are clustered and assortative. They share these topological features with some social networks. We argue that this similarity reveals the cliquey character of the social networks. In the model proposed here, a social... more

The line graphs are clustered and assortative. They share these topological features with some social networks. We argue that this similarity reveals the cliquey character of the social networks. In the model proposed here, a social network is the line graph of an initial network of families, communities, interest groups, school classes and small companies. These groups play the role of nodes, and individuals are represented by links between these nodes. The picture is supported by the data on the LiveJournal network of about 8 x 10^6 people. In particular, sharp maxima of the observed data of the degree dependence of the clustering coefficient C(k) are associated with cliques in the social network.