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.
1452553
Understanding research trends in conferences using paperLens
PaperLens is a novel visualization that reveals trends, connections, and activity throughout a conference community. It tightly couples views across papers, authors, and references. PaperLens was developed to visualize 8 years (1995-2002) of InfoVis conference proceedings and was then extended to visualize 23 years (1982-2004) of the CHI conference proceedings. This paper describes how we analyzed the data and designed PaperLens. We also describe a user study to focus our redesign efforts along with the design changes we made to address usability issues. We summarize lessons learned in the process of design and scaling up to the larger set of CHI conference papers.
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.
2712263
How users interact with biodiversity information using TaxonTree
Biodiversity databases have recently become widely available to the public and to other researchers. To retrieve information from these resources, users must understand the underlying data schemas even though they often are not content experts. Many other domains share this problem.We developed an interface, TaxonTree, to visualize the taxonomic hierarchy of animal names. We applied integrated searching and browsing so that users need not have complete knowledge either of appropriate keywords or the organization of the data.Our qualitative user study of TaxonTree in an undergraduate course is the first to describe usage patterns in the biodiversity domain. We found that tree-based interaction and visualization aided users' understanding of the data. Most users approached biodiversity data by browsing, using common, general knowledge rather than the scientific keyword expertise necessary to search using traditional interfaces. Users with different levels of interest in the domain had different interaction preferences.
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.
8642618
Stationary subdivision schemes reproducing polynomials
A new class of subdivision schemes is presented. Each scheme in this class is a quasi-interpolatory scheme with a tension parameter, which reproduces polynomials up to a certain degree. We find that these schemes extend and unify not only the well-known Deslauriers-Dubuc interpolatory schemes but the quadratic and cubic B-spline schemes. This paper analyzes their convergence, smoothness and accuracy. It is proved that the proposed schemes provide at least the same or better smoothness and accuracy than the aforementioned schemes, when all the schemes are based on the same polynomial space. We also observe with some numerical examples that, by choosing an appropriate tension parameter, our new scheme can remove undesirable artifacts which usually appear in interpolatory schemes with irregularly distributed control points.
355618
Reducing pattern delay variations for screening frequency dependent defects
The delay variations of a pattern set can come from two sources: (1) Different patterns sensitize different parts of the circuit and result in different delays. (2) The same pattern, applied on different chips, results in different delays because of process variations. For structural delay testing, these pattern variations may result in difficulty for finding an optimal test clock setting, which may significantly impact the defect screening effectiveness. This paper investigates the possibility of applying statistical timing analysis techniques to reduce pattern variations for structural delay testing. We develop an efficient statistical pattern-based timing simulator and devise pattern selection algorithms for reducing such variations. By constructing pattern sets with smaller variations, we show that higher screening effectiveness can be achieved. We present experimental results to demonstrate the advantages of our techniques based on benchmark circuits.
17892684
Refined statistical static timing analysis through
Statistical static timing analysis (SSTA) has been a popular research topic in recent years. A fundamental issue with applying SSTA in practice today is the lack of reliable and efficient statistical timing models (STM). Among many types of parameters required to be carefully modeled in an STM, spatial delay correlations are recognized as having significant impact on SSTA results. In this work, we assume that exact modeling of spatial delay correlations is quite difficult, and propose an experimental methodology to resolve this issue. The modeling accuracy requirement is relaxed by allowing SSTA to impose upper bounds and lower bounds on the delay correlations. These bounds can then be refined through learning the actual delay correlations from path delay testing on silicon. We utilize SSTA as the platform for learning and propose a Bayesian approach for learning spatial delay correlations. The effectiveness of the proposed methodology is illustrated through experiments on benchmark circuits.
11122198
Shared memory and distributed shared memory systems: A survey
Publisher Summary This chapter illustrates distributed shared memory (DSM) systems that are intended to combine the ease of programming of the shared-memory model with the scalability of the distributed-memory system. DSM systems aim to unify parallel processing systems that rely on message passing with the shared-memory systems. The chapter explores the design space for such systems and includes descriptions of both hardware- and software-supported DSM systems. The implementation prototypes of some of the systems are based on older technology and older software designs, making them appear to perform poorly.