47242941
A Fast Multi-scale Method for Drawing Large Graphs
We present a multi-scale layout algorithm for the aesthetic drawing of undirected graphs with straight-line edges. The algorithm is extremely fast, and is capable of drawing graphs of substantially larger size than any other algorithm we are aware of. For example, the algorithm achieves optimal drawings of 1000 vertex graphs in about 2 seconds. The paper contains graphs with over 6000 nodes. The proposed algorithm embodies a new multi-scale scheme for drawing graphs, which was motivated by the recently published multi-scale algorithm of Hadany and Harel [7]. It can significantly improve the speed of essentially any force-directed method (regardless of that method's ability of drawing weighted graphs or the continuity of its cost-function).
346060
A Multi-scale Algorithm for the Linear Arrangement Problem
Finding a linear ordering of the vertices of a graph is a common problem arising in diverse applications. In this paper we present a linear-time algorithm for this problem, based on the multi-scale paradigm. Experimental results are similar to those of the best known approaches, while the running time is significantly better, enabling it to deal with much larger graphs. The paper contains a general multi-scale construction, which may be used for a broader range of ordering problems.
1037525
Graph Drawing by High-Dimensional Embedding
We present a novel approach to the aesthetic drawing of undirected graphs. The method has two phases: first embed the graph in a very high dimension and then project it into the 2-D plane using principal components analysis. Running time is linear in the graph size, and experiments we have carried out show the ability of the method to draw graphs of 105 nodes in few seconds. The new method appears to have several advantages over classical methods, including a significantly better running time, a useful inherent capability to exhibit the graph in various dimensions, and an effective means for interactive exploration of large graphs.
122739950
Graph Drawing by High-Dimensional Embedding
2779311
The immune system as a reactive system: modeling T cell activation with statecharts
The construction of reliable reactive systems is considered to be one of the most challenging goals in the fields of software and system engineering. The definition of a reactive system suits biological systems at different levels, ranging from gene networks, developing embryos and the immune system. We report here the application of a tool developed for constructing computerized systems to the modeling and analysis of a biological system, the immune system. We use the language of statecharts within the framework of object-oriented modeling. The results described here indicate that this modeling strategy can contribute to the transition of biology from the phase of analysis to the phase of synthesis.
1830823
Playing with time: on the specification and execution of time-enriched LSCs
We extend live sequence charts (LSCs), a highly expressive variant of sequence diagrams, with timing constructs, thus making the language suitable for specifying the behavioral requirements of time-intensive systems. We follow R. Alur and T.A. Henzinger (see Software Tools for Technology Transfer, vol.1, p.86-109, 1997) in basing the extension on a single clock object. We have implemented the extension in full in our play-engine tool, which provides user-friendly ways to play in the timing constraints, together with a powerful mechanism that can execute, or play out, the time-enriched requirements directly, without the need for an intra-object system model. It seems that in addition to many advantages in testing and requirements engineering, for some kinds of systems this could lead to the requirements actually serving as the final implementation.
14408974
Towards an odor communication system
We propose a setup for an odor communication system. Its different parts are described, and ways to realize them are outlined. Our scheme enables an output device-the whiffer-to release an imitation of an odorant read in by an input device-the sniffer-upon command. The heart of the system is the novel algorithmic scheme that makes the scheme feasible. We are currently at work researching and developing some of the components that constitute the algorithm, and we hope that the description of the overall scheme in this paper will help to get other groups to join in this effort.