Visualization Evaluation And Optimization Of Complex Network Topology

The visualization of complex network topology is a data visualization technology based on graph layout algorithm to display topology and help users to obtain valuable information more intuitively,which has become the main technology for displaying network topology visualization.However,many complex network topology visualizations mainly focus on the realization of technology,ignoring the user's cognitive level,resulting in many visual features that do not satisfy the user's cognition,such as continuous intersection and node overlap,etc.,which make the network topology not well understood by users.Therefore,from the perspective of cognition,this article evaluates and optimizes visualization to help users choose better graph layout algorithms in line with cognition and improve users' cognitive performance on network topology.First,this paper proposes a visual evaluation method of complex network topology based on user cognition.The method obtains the user's cognitive performance(reaction time and correct rate)of important topological structures through cognitive experiments,and takes part of the cognitive results as a test data,and then quantifies the visual features that affect topological cognition in the visualization into index variables for evaluation,performs regression modelling analysis on the index variables and experimental cognitive performance to generate an objective evaluation model,and finally verify the model using the test data set in the experiment The effectiveness.Secondly,based on the front-end technology,this paper builds a complex network topology visualization evaluation platform,which implements the functions of different complex network topology visualization layout algorithms,cognitive evaluation and heat map visualization.In addition,based on the platform,this paper carries out an evaluation experiment.The experiment uses the evaluation model in the evaluation method of this paper to evaluate the cognitive effects of different layout algorithms and screen out the optimal layout algorithm.Finally,this article puts forward a complex network visualization force layout optimization algorithm based on simulated annealing algorithm.The optimization algorithm integrates the force layout algorithm into the simulated annealing algorithm,and designs a reasonable optimization function to reduce the visual features in the layout which are not conducive to the topology structure to achieve the purpose of improving the user's cognitive efficiency of the topology structure.The results of experimental analysis indicate that the regression model generated by the evaluation method can filter the visual layout with high cognitive performance of topology structure,therefore users can better understand the complex network topology information,and avoid repeated cognitive experiments on the layout to save human and material resources.Secondly,the comparison of the visualization results of the optimization algorithm and the force layout algorithm shows that the optimization algorithm makes the layout produce fewer edge crossings,more uniform edge lengths,and more uniformly distributed nodes,which can effectively improve the user's cognition of complex network topology.