Visualization of large citation networks with space-efficient multi-layer optimization

This paper describes a technique for visualizing large citation networks (or bibliography networks) using a space-efficient multi-layer optimization visualization, technique. Our technique first use a fast clustering algorithm to discover community structure in the bibliographic networks. The clustering process partitions an entire network into relevant abstract subgroups so that the visualization, can provide a clearer and less density of display of global view of the complete graph of citations. We next use a new space-efficient visualization algorithm to archive the optimization of graph layout within the limited display space so that our technique can theoretically handle a very large bibliography network with several thousands of elements. Our technique also employs rich graphics to enhance the attributed property of the visualization including publication years and number of citations. Finally, the system provides an interaction technique in cooperating with the layout to allow users to navigate through the citation network. Animation is also implemented to preserve the users' mental maps during the interaction

A usability study on the use of multi-context visualization

Graph visualization has been widely used in real-world applications, as it provides better presentation of overall data structure. However, there are navigation problems existing in deep and large relational datasets. To address these challenges, a new technique called multi-context visualization, which provides users with rich contextual information, has been proposed as the solution to the navigation in large scale datasets. This paper evaluates the multi-context visualization by conducting an experiment-based user study. To answer whether the more contextual information positively assist in making more accurate and easier decisions, it aims to evaluate the effectiveness and efficiency of the multi-context visualization, by measuring the user performance. Specifically, this usability test was designed to test if the use of multiple context views can improve navigation problems for deep and large relational data sets. © 2008 IEEE

Interactive visualization with user perspective: A new concept

With an astonishing amount of data generated for processing on a daily basic, it is essential to provide an effective methodology for understanding, reasoning and supporting decision making of large information spaces. This paper presents a new concept that provides an intelligent and interactive visualization in supporting large scale analysis. This aims to provide a much greater flexibility and control for the users to interactively customize the visualizations according to their preferences. A simple prototype is also presented to demonstrate the concept on hierarchical structures. Copyright © 2010 ACM

Visual clustering of spam emails for DDoS analysis

Networking attacks embedded in spam emails are increasingly becoming numerous and sophisticated in nature. Hence this has given a growing need for spam email analysis to identify these attacks. The use of these intrusion detection systems has given rise to other two issues, 1) the presentation and understanding of large amounts of spam emails, 2) the user-assisted input and quantified adjustment during the analysis process. In this paper we introduce a new analytical model that uses two coefficient vectors: 'density' and 'weight'for the analysis of spam email viruses and attacks. We then use a visual clustering method to classify and display the spam emails. The visualization allows users to interactively select and scale down the scope of views for better understanding of different types of the spam email attacks. The experiment shows that this new model with the clustering visualization can be effectively used for network security analysis. © 2011 IEEE

Drawing large weighted graphs using clustered force-directed algorithm

© 2014 IEEE. Clustered graph drawing is widely considered as a good method to overcome the scalability problem when visualizing large (or huge) graphs. Force-directed algorithm is a popular approach for laying graphs yet small to medium size datasets due to its slow convergence time. This paper proposes a new method which combines clustering and a force-directed algorithm, to reduce the computational complexity and time. It works by dividing a Long Convergence: LC into two Short Convergences: SC1, SC2, where SC1+SC2 < LC. We also apply our work on weighted graphs. Our experiments show that the new method improves the aesthetics in graph visualization by providing clearer views for connectivity and edge weights

Cost effectiveness and sustainability of sanitation options: A case study of South Can Tho - Technical Report

The Institute for Sustainable Futures (ISF), from the University of Technology Sydney, in collaboration with Can Tho University (CTU) and Can Tho Water Supply and Sewerage Company (WSSC) completed a 2-year collaborative research project assessing the wastewater infrastructure options for Can Tho City. The comparison of alternatives was made on the basis of cost-effectiveness and on the relative sustainability of the options, as determined through a participatory stakeholder sustainability assessment process with several government agencies in Can Tho

Enabling decision trend analysis with interactive scatter plot matrices visualization

© 2015 Elsevier Ltd. This paper presents a new interactive scatter plot visualization for multi-dimensional data analysis. We apply Rough Set Theory (RST) to reduce the visual complexity through dimensionality reduction. We use an innovative point-to-region mouse click concept to enable direct interactions with scatter points that are theoretically impossible. To show the decision trend we use a virtual Z dimension to display a set of linear flows showing approximation of the decision trend. We conducted case studies to demonstrate the effectiveness and usefulness of our new technique for analyzing the property of three popular data sets including wine quality, wages and cars. The paper also includes a pilot usability study to evaluate parallel coordinate visualization with scatter plot matrices visualization with RST results

Social representations of HIV/AIDS in five Central European and Eastern European countries: A multidimensional analysis

Cognitive processing models of risky sexual behaviour have proliferated in the two decades since the first reporting of HIV/AIDS, but far less attention has been paid to individual and group representations of the epidemic and the relationship between these representations and reported sexual behaviours. In this study, 494 business people and medics from Estonia, Georgia, Hungary, Poland and Russia sorted free associations around HIV/AIDS in a matrix completion task. Exploratory factor and multidimensional scaling analyses revealed two main dimensions (labelled ‘Sex’ and ‘Deadly disease’), with significant cultural and gender variations along both dimension scores. Possible explanations for these results are discussed in the light of growing concerns over the spread of the epidemic in this region

Acetylcholine induces fibrogenic effects via M2/M3 ACh receptors in NASH and in primary human hepatic stellate cells

BACKGROUND: The parasympathetic nervous system (PNS), via neurotransmitter Acetylcholine (ACh), modulates fibrogenesis in animal models. However, the role of ACh in human hepatic fibrogenesis is unclear. AIMS: We aimed to determine the fibrogenic responses of human hepatic stellate cells (hHSC) to ACh and the relevance of the PNS in hepatic fibrosis in patients with non-alcoholic steatohepatitis (NASH). METHODS: Primary hHSC were analysed for synthesis of endogenous ACh and acetylcholinesterase (AChE), and gene expression of choline acetyltransferase (ChAT) and muscarinic acetylcholine receptors (mAChR). Cell proliferation and fibrogenic markers were analysed in hHSC exposed to ACh, Atropine (Atrop), Mecamylamine (Mec), methoctramine and 4-Diphenylacetoxy-N-methylpiperidine methiodide (4-DAMP). MAChR expression was analysed in human NASH scored for fibrosis. RESULTS: We observed that hHSC synthesise ACh and AChE, and express ChAT and M1-M5 mAChR. We also show that M2 was increased during NASH progression, while both M2 and M3 were found upregulated in activated hHSC. Furthermore, endogenous ACh is required for hHSC basal growth. Exogenous ACh resulted in hHSC hyperproliferation via mAChR and PI-3 K and MEK signalling pathways, as well as increased fibrogenic markers. CONCLUSION: We show that ACh regulates hHSC activation via M2 and M3 mAChR involving the PI-3 K and MEK pathways in vitro. Finally, we provide evidence that the PNS may be involved in human NASH fibrosis