847742
Information Visualization of Attributed Relational Data
Traditional graph drawing is only concerned with viewing of abstract data and relations amount data items. It uses a graph model to present the data items and the relations and tries to geometrically convert the abstract graph into a 2D plane for visualization. There are many applications in this area, such as family trees, software design diagrams and web site-maps.The real world data that we want to visualize, however, is more complex than those that can be simply presented with traditional techniques, because it contains many domain-specific attributes.For example, in a web site-map (visualization) a simple graphical node can be used to represent a web page. However, this node is unable to represent some domain-specific attributes associated with the web page, such as the access frequency and the connectivity of the page in the web locality.This paper introduces a new model for Attributed Information Visualization that can be used to visualize the relational data with many associated attributes. We split the visualization model into two mappings between the abstract data and physical pictures, Geometric Mapping and Graphical Mapping.
12488692
Exploring UDDI Registries Using Modified OFDAV Browser
This paper introduces a framework of interactive navigating through the web-based UDDI Business Registries. By creating a 2D interactive visual interface, service requesters are able to visually navigate through the large information hierarchies that are usually used to present the UDDI Business Registries. Instead of using the traditional keywords or click-through searching methodologies, which are often inefficient and less obvious, we use a visualization technique, namely Online Force-Directed Animated Visualization (OFDA VJ, to create our visual interface. A simplified prototype with visual interface has been developed for the purpose of demonstration.
45897792
An Integrated Visual Intrusion Detection and Analysis System
17439148
A Visualization Model for Web Sitemaps
This paper describes a space-efficient visualization model that automatically crawls through a Web site and visualizes its sitemap. This model can be used especially for displaying and navigating a very large Web site in a two-dimensional (2D) plane and/or a three-dimensional (3D) space. The 2D visualization employs EncCon layout algorithm to effectively visualize a very large number of pages and relations at once in which it utilizes the space to display more information. This technique also employs a focus+context navigation method to enable the exploration of large sites. Animation is provided to preserve the user's mental map while exploring the Web site hierarchy. The 3D visualization extends the 2D EncCon layout algorithm to a three-dimensional space which aims to provide a more realistic look and feel of the information
12101937
Hierarchical information visualization using enccon model
This paper describes a new efficient approach for visualizing large hierarchical information. Our technique is based on the connection + enclosure visualization model [1] from which the area division is used for the recursive positioning of nodes, while a node-link diagram is still drawn to present the entire hierarchical structure. We inherit the advantages of Space-Optimized (SO) Tree technique [1] that can enhance the usability of display space by using area division. However, we replace a set of polygons used in SO Tree by a set of rectangles for the area division. This not only decreases the computation cost in calculating geometrical polygons, but also greatly reduces the human perceptual and cognitive loads spent on understanding the underlying hierarchical structure. We use semantic zooming technique to enlarge a particular viewing area and filter out the rest of structure that is less interested. The navigation is accommodated by animation in order to preserve the mental map [2].
22192509
A space-optimized tree visualization
We describe a new method for the visualization of tree structured relational data. It can be used especially for the display of very large hierarchies in a 2-dimensional space. We discuss the advantages and limitations of current techniques of tree visualization. Our strategy is to optimize the drawing of trees in a geometrical plane and maximize the utilization of display space by allowing more nodes and links to be displayed at a limit screen resolution. We use the concept of enclosure to partition the entire display space into a collection of local regions that are assigned to all nodes in tree T for the display of their sub-trees and themselves. To enable the exploration of large hierarchies, we use a modified semantic zooming technique to view the detail of a particular part of the hierarchy at a time based on user's interest. Layout animation is also provided to preserve the mental map while the user is exploring the hierarchy by changing zoomed views.
57256946
Slackened Memory Dependence Enforcement: Combining Opportunistic Forwarding with Decoupled Verification
An efficient mechanism to track and enforce memory dependences is crucial to an out-of-order microprocessor. The conventional approach of using cross-checked load queue and store queue, while very effective in earlier processor incarnations, suffers from scalability problems in modern high-frequency designs that rely on buffering many in-flight instructions to exploit instruction-level parallelism. In this paper, we make a case for a very different approach to dynamic memory disambiguation. We move away from the conventional exact disambiguation strategy and adopt an opportunistic method: we allow loads and stores to access an L0 cache as they are issued out of program order, hoping that with such a laissez-faire approach, most loads actually obtain the right value. To guarantee correctness, they execute a second time in program order to access the nonspeculative L1 cache. A discrepancy between the two executions triggers a replay. Such a design completely eliminates the necessity of real-time violation detection and thus avoids the conventional approach's complexity and the associated scalability issue. We show that even a simplistic design can provide similar performance level achieved with a conventional queue-based approach with optimisticallysized queues. When simple, optional optimizations are applied, the performance level is close to that achieved with ideally-sized queues.
7442937
SEED: Scalable, efficient enforcement of dependences
Instruction issue logic is a critical component in modern high-performance out-of-order processors. The ever increasing latencies found in modern processors, mostly associated with memory accesses and longer pipelines, can be attenuated using large issue queues. Conventional designs rely on atomic wakeup-select cycles to ensure compact scheduling. These designs must aggressively utilize broadcasting, compaction, and heavily-ported structures that scale poorly in terms of both power consumption and access time. To provide high scheduling flexibility and large instruction capacity without incurring prohibitive latency and energy overhead, we propose a novel scheme that uses an out-of-order, broadcast-free instruction wakeup block feeding an in-order scheduler. Multi-banked, index-based structures are used throughout this scheme to provide a high degree of scalability while achieving efficient dependence tracking, resulting in good overall performance and energy efficiency. We call this design "Scalable, Efficient Enforcement of Dependences (SEED)". We present a detailed design and analysis of SEED through an extensive evaluation. Compared to a conventional issue queue design, which is assumed favorably to scale in size without any impact on cycle time, the performance degradation of our design is 3% for both INT and FP suites of SPEC CPU2000. For such a small performance cost, SEED enjoys a 19% reduction in total chip power consumption for a 32-entry configuration. We also synthesize SEED and a conventional issue logic with 90nm standard cell logic. Synthesis results show that SEED can cycle twice the speed of a conventional issue logic of equivalent size. Cycling at the same frequency, SEED consumes ten times less dynamic power and five times less static power while achieving substantial area savings.
62155376
In VINI veritas: realistic and controlled network experimentation
This paper describes VINI, a virtual network infrastructure that allows network researchers to evaluate their protocols and services in a realistic environment that also provides a high degree of control over network conditions. VINI allows researchers to deploy and evaluate their ideas with real routing software, traffic loads, and network events. To provide researchers flexibility in designing their experiments, VINI supports simultaneous experiments with arbitrary network topologies on a shared physical infrastructure. This paper tackles the following important design question: What set of concepts and techniques facilitate flexible, realistic, and controlled experimentation (e.g., multiple topologies and the ability to tweak routing algorithms) on a fixed physical infrastructure? We first present VINI's high-level design and the challenges of virtualizing a single network. We then present PL-VINI, an implementation of VINI on PlanetLab, running the "Internet In a Slice". Our evaluation of PL-VINI shows that it provides a realistic and controlled environment for evaluating new protocols and services.
11321375
An overlay data plane for PlanetLab
PlanetLab is a geographically distributed overlay platform designed to support the deployment and evaluation of planetary-scale network services. It currently includes over 500 machines spanning 252 sites and 29 countries, and has supported over 450 research projects. PlanetLab can support large-scale overlays running in slices (i.e., collections of distributed virtual machines). It has significantly lowered the barriers to deploying overlays. The paper describes how to lower them further by introducing a general data plane for overlay networks. Researchers can plug their own control planes into this data plane to run fully functional overlays easily on PlanetLab, and students can use the overlay data plane as a hands-on tool for learning about internetworking concepts. The overlay data plane is the first step in the "Internet-in-a-slice" project, which will let members of the PlanetLab community experiment with virtual Internets running on PlanetLab.
34980398
Efficient Checkers for Number-Theoretic Computations
Blum has recently proposed a new approach to the problem of program correctness, the program checker. Here, efficient program checkers are presented for two important number theory problems, integer GCD and modular exponentiation. The former result answers an open problem posed by Blum. The latter result paves the way for more robust cryptographic programs, as modular exponentiation is the basis for several cryptosystems. Taken together, these results lay the foundation for more reliable number-theoretic programs.