July 31, 2018 / Leave a comment

Efficient message forwarding in mobile ad hoc network in disaster scenarios is challenging because location information on the boundary and interior nodes is often unavailable. Information related to boundary nodes can be used to design efficient routing protocols as well as to prolong the battery power of devices along the boundary of an ad hoc network. In this article, we developed an algorithm, CWBound, which discovers boundary nodes in a complex non-convex mobile ad hoc (CNCAH) networks.

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March 20, 2018 / Leave a comment

A graph layout problem, or visualization problem, refers to a set of nodes and a set of relationships (edges) built on top of this set of nodes, calculating the position of the nodes and drawing each edge as a line or curve.

One of the most important research directions in the visualization technology of graphs is the study of graph layout algorithms. The core content of the graph layout algorithm research is to study how to display the graph structure in a better way. E.g. force-directed algorithms.

The comprehensive workflow for basic force-directed algorithms are summarized below:

- Kamada-Kawai Algorithm
- Fruchterman Reingold Algorithm
- ForceAtlas2 Algorithm
- LinLog Algorithm
- Davidson and Harel Algorithm

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November 23, 2017 / Leave a comment

CNCAHNetGenerator is written in Java 7, to enable the creation of CNCAH networks of arbitrary node and edge types. (more…)

November 23, 2017 / Leave a comment

CNCAH shapes generated by the CNCAHNetGenerator. You can download the dataset from here. (more…)

November 23, 2017 / Leave a comment

Force-directed algorithms such as the Kamada-Kawai algorithm have shown promising results for solving the boundary detection problem in a mobile ad hoc network. However, the classical Kamada-Kawai algorithm does not scale well when it is used in networks with large numbers of nodes. It also produces poor results in non-convex networks. To address these problems, this paper proposes an improved version of the Kamada-Kawai algorithm. The proposed extension includes novel heuristics and algorithms that achieve a faster energy level reduction. Our experimental results show that the improved algorithm can significantly shorten the processing time and detect boundary nodes with an acceptable level of accuracy.

*The authorâ€™s version of a work that was accepted for publication can be downloaded from Accelerating Kamada-Kawai for boundary detection in Mobile Ad-Hoc network.***
Se-Hang Cheong**, and Yain-Whar Si. "Accelerating the Kamada-Kawai algorithm for boundary detection in a mobile ad hoc network." ACM Transactions on Sensor Networks (TOSN) 13.1 (2016): 3.