A computing framework for integrating interactive visualization in HPCC applications

Network-based concurrent computing and interactive data visualization are two important components in industry applications of high-performance computing and communication. We propose an execution framework to build interactive remote visualization systems for real-world applications on heterogeneous parallel and distributed computers. Using a dataflow model of a commercial visualization software AVS in three case studies, we demonstrate a simple, effective, and modular approach to couple parallel simulation modules into an interactive remote visualization environment. The applications described in this paper are drawn from our industrial projects in financial modeling, computational electromagnetics and computational chemistry. Copyright © 1999 John Wiley & Sons, Ltd.     

DaisyViz: A model-based user interface toolkit for interactive information visualization systems

While information visualization technologies have transformed our life and work, designing information visualization systems still faces challenges. Non-expert users or end-users need toolkits that allow for rapid design and prototyping, along with supporting unified data structures suitable for different data types (e.g., tree, network, temporal, and multi-dimensional data), various visualization, interaction tasks. To address these issues, we designed DaisyViz, a model-based user interface toolkit, which enables end-users to rapidly develop domain-specific information visualization applications without traditional programming. DaisyViz is based on a user interface model for information (UIMI), which includes three declarative models: data model, visualization model, and control model. In the development process, a user first constructs a UIMI with interactive visual tools. The results of the UIMI are then parsed to generate a prototype system automatically. In this paper, we discuss the concept of UIMI, describe the architecture of DaisyViz, and show how to use DaisyViz to build an information visualization system. We also present a usability study of DaisyViz we conducted. Our findings indicate DaisyViz is an effective toolkit to help end-users build interactive information visualization systems.     

Chiron parallel program performance visualization system

Chiron is a prototype visualization system for displaying the memory system performance of shared memory multiprocessor applications. The system uses 3D graphics techniques to display large amounts of both code-oriented and data-oriented information. Chiron is designed to isolate problems such as low cache block utilization, improper layout of data in memory resulting in excessive replacement interference, and improper partitioning of work among the processors resulting in excessive coherence interference. A 3D interactive user interface provides the user with flexibility in displaying the data and facilitates the job of focusing in on memory bottlenecks. The paper describes the design and implementation of Chiron, and illustrates its use.     

Task-specific visualization design

This case study in operational weather forecasting demonstrates the principles of task-specific visualization design: defining user needs, implementing that definition, and establishing techniques for different user goals. The current applications can generate visualizations for the Web after an intermediate step of migrating the products to a Web server. This proves advantageous in an operational environment because the forecaster has content control. However, direct generation within a Web browser, which requires a simplified user interface and content, will require further refinement of the task decomposition. The notion of task-driven customization of content and interface has succeeded in weather forecasting, but the idea also applies to other domains. The potential benefits should encourage visualization designers to adopt these principles in their application development     

Visualization systems on the Information Technology-Based Laboratory

The Center for Promotion of Computational Science and Engineering has developed a detailed design and prototype of the Information Technology Based Laboratory (ITBL). A software group forms the basic ITBL framework and makes up this infrastructure. The infrastructure gives registered users access to any supercomputer within the ITBL for the purpose of numerical simulations and supplies them with tools for discussion sessions among ITBL user groups or communities. When a result is speculated, it's important for every member of the community to see, at the same time, images of the simulation results. To achieve this, we developed visualization systems on the ITBL infrastructure software equipped with efficient remote visualization and collaborative visualization functions. We based the two core visualization systems-the parallel tracking steering (Patras)/ITBL and the application visualization system (AVS)/ITBL-on the existing visualization tools Patras and AVS/Express.     

A unified approach to adapt scientific visualization systems to third-party solvers

This paper presents a new unified approach to adapt scientific visualization systems to third-party solvers implemented on different software and hardware platforms. This approach allows building multiplatform visualization systems, enables automatic conversion of input and output data from any solver into a rendering-compatible format, and provides real-time generation of high-quality images. The automated adaptation of visualization systems to third-party solvers is based on ontological engineering methods. Multiplatform portability is provided by the automatic generation of a graphical user interface (GUI) for each particular operating system and by preprocessing the data to be rendered by using heuristic-based tools, which ensures compatibility with different hardware and software platforms, including desktop computers and mobile devices. In addition, an original anti-aliasing algorithm is proposed to ensure high quality of resulting images. Based on the proposed approach, a multiplatform scientific visualization system called SciVi is developed, which is successfully used for solving various real-world scientific visualization problems from different application domains.     

GerbilSphere: Inner sphere network visualization

Advanced techniques are needed to understand the underlying topologies of large complex networks. This paper introduces a novel way to address the issue of visualizing large-scale network topologies. We propose an inner sphere visualization method that projects the network topology on the inside of a sphere. User navigation around the network is accomplished through moving the sphere around the user’s point of view. Previous research has shown that the spatial cognition ability in humans greatly affects the usefulness of a user interface. In this direction, we performed two empirical experiments to test the usefulness of viewing topologies on a sphere compared to a flat surface. The user study indicates that network navigation on a sphere is faster but can also be confusing. Thus, we add guidance tips to create a more intuitive user interface and to improve navigability. Our inner sphere visualization method is implemented as a tool for dynamic interactive network visualization called GerbilSphere (available at http://cse.unr.edu/～mgunes/gerbilSphere).     

A Windows Application for Real-Time Fetal ECG Analysis

Analysis of the fetal electrocardiogram (FECG) from abdominal recordings may be used as a noninvasive technique to assess fetal well being. Consequently, interest has arisen in the development of a real-time fetal ECG monitoring system. In this paper, we present a Windows user interface developed for our antenatal FECG analysis system. The program (FECGV1), written in C++, consists of three principal modules: System Setup, Real-Time FECG Analysis, and Result Review. By adopting the Windows' graphical user interface and object-oriented programming methodology, the system software accomplished the goals of visualization, easy use, extensibility, and user adaptability. Preliminary clinical application has shown that this approach provides a strong basis for a solution to real-time antenatal FECG analysis.     

An architecture for Java-based real-time distributed visualization

In this paper, we present a Java-based software architecture for real-time visualization that utilizes a cluster of conventional PCs to generate high-quality interactive graphics. Normally, a large multiprocessor computer would be needed for interactive visualization tasks requiring more processing power than a single PC can provide. By using clusters of PCs, enormous cost savings can be realized, and proprietary "high-end" hardware is no longer necessary for these tasks. Our architecture minimizes the amount of synchronization needed between PCs, resulting in excellent scalability. It provides a modular framework that can accommodate a wide variety of rendering algorithms and data formats, provided that the rendering algorithms can generate pixels individually and the data is duplicated on each PC. Demonstration modules that implement ray tracing, fractal rendering, and volume rendering algorithms were developed to evaluate the architecture. Results are encouraging-using 15 PCs connected to a standard 100 Megabit/s Ethernet network, the system can interactively render simple to moderately complex data sets at modest resolution. Excellent scalability is achieved; however, our tests were limited to a cluster of 15 PCs. Results also demonstrate that Java is a viable platform for real-time distributed visualization.     

An architecture for distributed visualization of technical processes

The goal of the work presented here was to create the prototype of a graphical user interface for process visualization which requires only a fraction of the memory and processing power needed by today's de-facto industry standards for graphical user interfaces. As a result, an application framework for distributed process visualization called ‘Vision’ was developed. This paper describes the architecture of ‘Vision’, which achieved our goals by the consequent use of object-oriented design in the components of the user interface. The system offers a fully functional GUI as a basis, with special capabilities for fail-safe distribution of process-related events within a network of visualization stations. Several basic classes for visualizing process data are included.     

Style grammars for interactive visualization of architecture

Interactive visualization of architecture provides a way to quickly visualize existing or novel buildings and structures. Such applications require both fast rendering and an effortless input regimen for creating and changing architecture using high-level editing operations that automatically fill in the necessary details. Procedural modeling and synthesis is a powerful paradigm that yields high data amplification and can be coupled with fast-rendering techniques to quickly generate plausible details of a scene without much or any user interaction. Previously, forward generating procedural methods have been proposed where a procedure is explicitly created to generate particular content. In this paper, we present our work in inverse procedural modeling of buildings and describe how to use an extracted repertoire of building grammars to facilitate the visualization and quick modification of architectural structures and buildings. We demonstrate an interactive application where the user draws simple building blocks and, using our system, can automatically complete the building "in the style of other buildings using view-dependent texture mapping or nonphotorealistic rendering techniques. Our system supports an arbitrary number of building grammars created from user subdivided building models and captured photographs. Using only edit, copy, and paste metaphors, the entire building styles can be altered and transferred from one building to another in a few operations, enhancing the ability to modify an existing architectural structure or to visualize a novel building in the style of the others.     

Semantic feedback in the Higgens UIMS

Almost all applications using interactive graphics contain important structures and concepts which are deeper than the geometres used to display them to the user. One of the major tasks of the system implementer is to cause the user interface to reflect this deeper structure accurately so that it may be directly manipulated by the user. The authors describe a tool, the Higgens user interface management system (UIMS), which can automate much of this task for a wide class of systems using interactive graphics. It is able to generate graphical user interfaces automatically from a high-level interface specification. These specifications are primarily nonprocedural in nature. They describe how graphical images can be automatically derived and updated based on applications entities, and how graphical inputs can be translated back into terms which are appropriate to the application     

Interactive visualization of dependencies

We present an interactive tool for browsing course requisites as a case study of dependency visualization. This tool uses multiple interactive visualizations to allow the user to explore the dependencies between courses. A usability study revealed that the proposed browser provides significant advantages over traditional methods, in terms of learnability, efficiency and user confidence. The results are discussed within a general framework for interactive visualization of dependencies.     

DUET — A database user interface design environment

The DUET database user interface management system aims to help database application programmers to create, modify, and maintain interactive graphical user interfaces for different applications. DUET supports the creation of a complete user interface via direct manipulation techniques. It provides a large set of database widgets which are necessary for database applications. DUET provides facilities to step through the validation of a created user interface. A user interface can be saved as C code which can be integrated into a database backend. In this paper, the features and the architecture of DUET are presented.     

Multiresolution representation and visualization of volume data

A system to represent and visualize scalar volume data at multiple resolution is presented. The system is built on a multiresolution model based on tetrahedral meshes with scattered vertices that can be obtained from any initial dataset. The model is built off-line through data simplification techniques, and stored in a compact data structure that supports fast on-line access. The system supports interactive visualization of a representation at an arbitrary level of resolution through isosurface and projective methods. The user can interactively adapt the quality of visualization to requirements of a specific application task and to the performance of a specific hardware platform. Representations at different resolutions can be used together to further enhance interaction and performance through progressive and multiresolution rendering     

Visualization of FE-data,interactively and on video

This article presents a computational environment for visualization of FE-data and video production. The general ways to visualize FE-data are discussed and software suitable for building visualization applications are described. The pitfalls and considerations to be taken in video production are pointed out and described. The procedure in video editing is exemplified for one system.Two applications of animations are described. One has been developed to get a deeper insight and understanding of how a 3D mesh generator works. The other is a presentation of results from a time-stepping procedure of a wave propagation problem on video. The tools we have chosen for our visualization system are AVS (Application Visualization System) from AVS/UNIRAS, and Video Machine from FAST.     

Interactive visualization and analysis of transitional flow

A stand-alone visualization application has been developed by a multi-disciplinary, collaborative team with the sole purpose of creating an interactive exploration environment allowing turbulent flow researchers to experiment and validate hypotheses using visualization. This system has specific optimizations made in data management, caching computations, and visualization allowing for the interactive exploration of datasets on the order of 1TB in size. Using this application, the user (co-author Calo) is able to interactively visualize and analyze all regions of a transitional flow volume, including the laminar, transitional and fully turbulent regions. The underlying goal of the visualizations produced from these transitional flow simulations is to localize turbulent spots in the laminar region of the boundary layer, determine under which conditions they form, and follow their evolution. The initiation of turbulent spots, which ultimately lead to full turbulence, was located via a proposed feature detection condition and verified by experimental results. The conditions under which these turbulent spots form and coalesce are validated and presented.     

A visualization programming environment for multicomputers

The programming and run-time environment used for the authors' multicomputer visualization software are described. The particular approach to using multicomputers for scientific visualization provides a uniform interface to system and communications facilities and promotes modularity and code reuse. No breakthrough technology is involved; rather, a collection of methods that have been developed by others has been optimized for visual computing applications and unified into a system that is simple to use and easy to port to new hardware. The C language is used. Initial experience with the system has been good     

Parallelized fusion visualization system

The speed-up of supercomputers has increased the complexity of simulations. To analyze such kind of data, we believe that new types of visualization software are needed. Therefore, we have been developing a visualization system called “Fusion Visualization”, and the progresses were reported in the AROB 18th and 19th International Symposiums. We introduced the overall concept at the AROB 18th International Symposium, and then demonstrated a sample of flow visualization in a blood vessel in the AROB 19th International Symposium. To extend our system to enable the handling of larger data, we have implemented the proposed system on a parallelized visualization system; AVS/Express PCE (Parallel Cluster Edition). This paper describes the implementation and the benchmark results.