6809024
TreePlus: Interactive Exploration of Networks with Enhanced Tree Layouts
Despite extensive research, it is still difficult to produce effective interactive layouts for large graphs. Dense layout and occlusion make food Webs, ontologies and social networks difficult to understand and interact with. We propose a new interactive visual analytics component called TreePlus that is based on a tree-style layout. TreePlus reveals the missing graph structure with visualization and interaction while maintaining good readability. To support exploration of the local structure of the graph and gathering of information from the extensive reading of labels, we use a guiding metaphor of "plant a seed and watch it grow." It allows users to start with a node and expand the graph as needed, which complements the classic overview techniques that can be effective at (but often limited to) revealing clusters. We describe our design goals, describe the interface and report on a controlled user study with 28 participants comparing TreePlus with a traditional graph interface for six tasks. In general, the advantage of TreePlus over the traditional interface increased as the density of the displayed data increased. Participants also reported higher levels of confidence in their answers with TreePlus and most of them preferred TreePlus
22808943
Exploring content-actor paired network data using iterative query refinement with NetLens
Networks have remained a challenge for information retrieval and visualization because of the rich set of tasks that users want to accomplish. This paper demonstrates a tool, NetLens, to explore a content-actor paired network data model. The NetLens interface was designed to allow users to pose a series of elementary queries and iteratively refine visual overviews and sorted lists. This enables the support of complex queries that are traditionally hard to specify in node-link visualizations. NetLens is general and scalable in that it applies to any dataset that can be represented with our abstract content-actor data model
26612484
Visualizing Graphs as Trees: Plant a Seed and Watch it Grow
TreePlus is a graph browsing technique based on a tree-style layout. It shows the missing graph structure using interaction techniques and enables users to start with a specific node and incrementally explore the local structure of graphs. We believe that it supports particularly well tasks that require rapid reading of labels.
7825415
Understanding Eight Years of InfoVis Conferences Using PaperLens
We present PaperLens, a visualization that reveals connections, trends, and activity throughout the InfoVis conference community for the last 8 years. It tightly couples views across papers, authors, and references. This paper describes how we analyzed the data, the strengths and weaknesses of PaperLens, and interesting patterns and relationships we have discovered using PaperLens.
283122
Electronic voting system usability issues
With recent troubles in U.S. elections, there has been a nationwide push to update voting systems. Municipalities are investing heavily in electronic voting systems, many of which use a touch screen. These systems offer the promise of faster and more accurate voting, but the current reality is that they are fraught with usability and systemic problems. This paper surveys issues relating to usability of electronic voting systems and reports on a series of studies, including one with 415 voters using new systems that the State of Maryland purchased. Our analysis shows these systems work well, but have several problems, and many voters have concerns about them.
2438079
Visualizations for taxonomic and phylogenetic trees
MOTIVATION
Despite substantial efforts to develop and populate the back-ends of biological databases, front-ends to these systems often rely on taxonomic expertise. This research applies techniques from human-computer interaction research to the biodiversity domain.


RESULTS
We developed an interactive node-link tool, TaxonTree, illustrating the value of a carefully designed interaction model, animation, and integrated searching and browsing towards retrieval of biological names and other information. Users tested the tool using a new, large integrated dataset of animal names with phylogenetic-based and classification-based tree structures. These techniques also translated well for a tool, DoubleTree, to allow comparison of trees using coupled interaction. Our approaches will be useful not only for biological data but as general portal interfaces.
1712871
Quasi-interpolants Based Multilevel B-Spline Surface Reconstruction from Scattered Data
This paper presents a new fast and local method of 3D surface reconstruction for scattered data. The algorithm makes use of quasi-interpolants to compute the control points from a coarse to fine hierarchy to generate a sequence of bicubic B-spline functions whose sum approaches to the desired interpolation function. Quasi-interpolants gives a procedure for deriving local spline approximation methods where a B-spline coefficient only depends on data points taken from the neighborhood of the support corresponding B-spline. Experimental results demonstrate that high-fidelity reconstruction is possible from a selected set of irregular samples.
34238463
An Efficient E-mail Monitoring System for Detecting Proprietary Information Outflow Using Broad Concept Learning
The automatic text categorization (ATC) is an emerging field that is technically based on the machine learning and information retrieval. Traditional machine learning usually builds a model that captures the behavior of the ‘concept’ from the training instances. Following this context, the ATC learns the concept from text data such as digital text documents, web pages, or e-mail texts. In this paper, we categorize the concepts that have been dealt by ATC into two groups: broad concepts and narrow concepts. Broad concepts are difficult to learn than narrow concepts. We propose a multi model approach where multiple local models are constructed to learn the broad concepts. Some experimental results showed that the multi model approach turned out to be effective in learning the confidentiality of company.
33958226
Performance evaluation of a communication optimization model in network-based parallel computing
Network based distributed computing has been gaining popularity over the past decade. Many parallel programming languages and related parallel programming modes are becoming widely accepted. However, the execution of parallel applications on distributed systems has been hampered by the high communication overhead. To reduce the communication overhead and the completion time of a parallel application, we propose a key message model for parallel computing on network of workstations (NOWs). In the key message model, all messages generated in a key message path are prioritized. A key message path in a task graph is defined as the path that is optimized by the key message algorithm. All messages generated in a key message path are prioritized. Besides, the key message algorithm automatically finds the key message paths. In this paper, we first describe the algorithm that identifies the key messages to be prioritized in a parallel application, then analyze the cost of the algorithm, and finally evaluate the performance of the algorithm in a simulation. Our preliminary analysis of the algorithm shows improvement over the system which does not use prioritization scheme.
509415
A New Class of Non-stationary Interpolatory Subdivision Schemes Based on Exponential Polynomials
We present a new class of non-stationary, interpolatory subdivision schemes that can exactly reconstruct parametric surfaces including exponential polynomials. The subdivision rules in our scheme are interpolatory and are obtained using the property of reproducing exponential polynomials which constitute a shift-invariant space. It enables our scheme to exactly reproduce rotational features in surfaces which have trigonometric polynomials in their parametric equations. And the mask of our scheme converges to that of the polynomial-based scheme, so that the analytical smoothness of our scheme can be inferred from the smoothness of the polynomial based scheme.
529060
Issues in Dataflow Computing
Publisher Summary This chapter discusses the basic principles of the dataflow model, along with its major attributes and the language support for dataflow. It provides a general description of the dataflow model of execution based on the pioneering works of research groups at Massachusetts Institute of Technology (MIT) and the University of Manchester namely, the static dataflow machine, tagged-token dataflow architecture, and Manchester machine. Major problems encountered in the design of these machines are outlined. The chapter surveys current dataflow projects and provides a comparison of the architectural characteristics and evolutionary improvements in dataflow computing. It discusses the difficulties in handling data structures in a dataflow environment. An overview of the methods for representing data structures is provided. This is supplemented by various issues required to handle data structures in a dataflow environment. The chapter addresses the issue of program allocation. Several proposed methodologies are presented and the various issues involved in program allocation are discussed. The resource requirements for dataflow computations are examined.