ppxscal/embedding_network huggingface dataset:
Integrating graphics and abstract data to visualize temporal constraints
Authors: Louis Hoebel, William Lorensen, Ken Martin
Venue: ACM SIGART Bulletin (1998)

Traditionally, visualization is the transformation of data into information that can be rendered using computer graphics techniques. Visualization combines techniques and representations from computer graphics, computer vision, and image processing. In distributed and hierarchical operations and processes, such as for command and control or logistics and planning, visualization is the central mechanism for communicating the state of the situation and operations. The major challenge of visualization is to filter, tailor, and present the information in compact forms that can be efficiently created and displayed. In contrast to many visualization problems, these domains have what seems to be an overwhelming variety and quantity of information. We address aspects of this problem with the graphical visualization of abstract temporal information in a concrete spatio-temporal framework.
Some (17q, 17, 2) and (25q, 25, 3)BIBD Constructions
Authors: Marco Buratti
Venue: Designs, Codes and Cryptography (1999)

We give the explicit construction of a regular (17q, 17,2)-BIBD for any prime power q\equiv17\ (\mod 32) such that 2 is not a 4th power in GF(q) and the explicit construction of a regular (25q, 25,3)-BIBD for any prime powerq\equiv25\ (\mod 48) such that \sqrt{3} and \sqrt{3}+3 are non-squares in GF(q).
Data mining (Invited talk. Abstract only): crossing the Chasm
Authors: Rakesh Agrawal
Venue: Proceedings of the fifth ACM SIGKDD international conference on Knowledge discovery and data mining (1999)

Data mining has attracted tremendous interest in the research community as well as commercial market place. The last few years have witnessed a flurry of technical innovations and introduction of comercial products. The next major challenge facing data mining is to make a transition from a niche technology to a main stream technology. I will present key technical and environmental issues that must be addressed for a successful transition.
Appropriations and patterns in the use of group support systems
Authors: Katherine M. Chudoba
Venue: ACM SIGMIS Database (1999)

This paper describes a macro-level coding scheme to distinguish patterns that occur in groups using a group support system (GSS). The coding scheme has roots in adaptive structuration theory (AST) with its emphasis on how technology is appropriated or used, and discourse analysis that requires one consider the context of the larger discussion when analyzing textual data. The macro-level coding scheme revolves around junctures that occur during group meetings such as when a group either chooses to use the GSS software or chooses to accomplish some aspect of the task without the software. After identifying a juncture, a brief description is written detailing how group members responded to the opportunity presented by the juncture. Qualitative analysis is then used to identify patterns in how the technology is used. Application of the coding scheme is demonstrated with data gathered from 17 groups that met three times over a two-week period.
Design of Homogeneous Time-Varying Stabilizing Control Laws for Driftless Controllable Systems Via Oscillatory Approximation of Lie Brackets in Closed Loop
Authors: Pascal Morin
Venue: SIAM Journal on Control and Optimization (1999)

A constructive method for time-varying stabilization of smooth driftless controllable systems is developed. It provides time-varying homogeneous feedback laws that are continuous and smooth away from the origin. These feedbacks make the closed-loop system globally exponentially asymptotically stable if the control system is homogeneous with respect to a family of dilations and, using local homogeneous approximation of control systems, locally exponentially asymptotically stable otherwise.The method uses some known algorithms that construct oscillatory control inputs to approximate motion in the direction of iterated Lie brackets that we adapt to the closed-loop context.
Objective viewpoint: Java AWT layout management 101
Authors: George Crawford,  III
Venue: Crossroads (1998)

This article provides a brief summary of basic layout management in the Java Abstract Window Toolkit (AWT) and is intended to serve as a foundation for more sophisticated AWT programming.
A Robust, Parallel Homotopy Algorithm for the Symmetric Tridiagonal Eigenproblem
Authors: Michael H. Oettli
Venue: SIAM Journal on Scientific Computing (1999)

The homotopy method has been used in the past for finding zeros of nonlinear functions. Early algorithms based on the homotopy approach for solving the symmetric eigenproblem suffer either from insufficient orthogonality between computed eigenvectors or from low efficiency. A new algorithm presented in this article overcomes these problems by using deflation of close eigenpairs and maintains a high degree of parallelism by applying the divide-and-conquer principle. A numerical comparison of a sequential implementation of the new algorithm shows that it is competitive with other well-established algorithms both in speed and accuracy. Algorithms based on the homotopy method are excellent candidates for multicomputers because of their natural parallelism. This article examines how the algorithm can be implemented on distributed-memory multicomputers. The experimental performance results obtained on an Intel Paragon multicomputer are very satisfying.
Visual similarity of pen gestures
Authors: A. Chris Long,  Jr., James A. Landay, Lawrence A. Rowe, Joseph Michiels
Venue: Proceedings of the SIGCHI conference on Human factors in computing systems (2000)

Pen-based user interfaces are becoming ever more popular. Gestures (i.e., marks made with a pen to invoke a command) are a valuable aspect of pen-based UIs, but they also have drawbacks. The challenge in designing good gestures is to make them easy for people to learn and remember. With the goal of better gesture design, we performed a pair of experiments to determine why users find gestures similar. From these experiments, we have derived a computational model for predicting perceived gesture similarity that correlates 0.56 with observation. We will incorporate the results of these experiments into a gesture design tool, which will aid the pen-based UI designer in creating gesture sets that are easier to learn and more memorable.
DG2VHDL: A Tool to Facilitate the High Level Synthesisof Parallel Processing Array Architectures
Authors: Andrew Stone, Elias S. Manolakos
Venue: Journal of VLSI Signal Processing Systems (2000)

We present DG2VHDL, a design tool which can automatically translate abstract algorithmic descriptions, known as Dependence Graphs, to synthesizable VHDL models and testbenches representative of distributed memory and control processor arrays, known as Signal Flow Graphs. This translation facilitates the rapid exploration of the large space of available parallel architectures for a given problem and frees the designer from having to code and test separately, using a Hardware Description Language, every candidate architecture under consideration. It is shown that the quality and scalability of the automatically generated VHDL models is near optimal, in the sense that the time required to synthesize them as well as the area of the resulting hardware grows at the lowest possible rate with the problem size. This makes possible the high level synthesis of processor arrays for large size real world problems, such as the computation of the Discrete Wavelet Transform and the estimation of Higher Order Statistics, that are presented as case studies.
A three-port nRERL register file for ultra-low-energy applications
Authors: Jun-Ho Kwon, Joonho Lim, Soo-Ik Chae
Venue: Proceedings of the 2000 international symposium on Low power electronics and design (2000)

In this paper, we propose an adiabatic register file for ultra-low-energy applications, which uses a new reversible adiabatic logic, nRERL [1]. The nRERL register file discards garbage information with minimal energy dissipation. We designed a 16x8b three-port nRERL register file. From SPICE simulations, we found that the nRERL register file consumes less than 10% of the energy consumed in the conventional register file at the frequency of lower than 1MHz. We also describe how to design a RAM, a large array of the storage cells
Efficient distributed simulation of a communication switch with bursty sources and losses
Authors: A. S. McGough, I. Mitrani
Venue: Proceedings of the fourteenth workshop on Parallel and distributed simulation (2000)

Algorithms for simulating an ATM switch on a distributed memory multiprocessor are described. These include parallel generation of bursty arrival streams, along with the marking and deleting of lost cells due to buffer overflows. These algorithms increase the amount of computation carried out independently by each processor, and reduce the communication between the processors. When the number of cells lost is relatively small, the run time of the simulation is approximately O(N/P), where N is the total number of cells simulated and P is the number of processors. The cells are processed in intervals of fixed length; that length affects the structure and the performance of the algorithms.
Information Security, Mathematics, and Public-Key Cryptography
Authors: Simon Blake-Wilson
Venue: Designs, Codes and Cryptography (2000)

Public-key cryptography is today recognized as an important tool in the provision of information security. This article gives an overview of the field on the occasion of its 22nd birthday.
An O(log(n)4/3) space algorithm for (s, t) connectivity in undirected graphs
Authors: Roy Armoni, Amnon Ta-Shma, Avi Widgerson, Shiyu Zhou
Venue: Journal of the ACM (JACM) (2000)

We present a deterministic algorithm that computes st-connectivity in undirected graphs using O(log 4/3n) space. This improves the previous O(log3/2n) bound of Nisan et al. [1992].
Teaching computer networking using open source software
Authors: Daniel Nelson, Yau Man Ng
Venue: ACM SIGCSE Bulletin (2000)

For the past seven years we have taught a subject entitled Network Software and Management (NSM) for both computer science and electrical engineering students. We discuss the evolution of this subject syllabus in response to the changing requirements of the workplace environment, ever improving technology and the need to combine theory and practice in teaching subjects such as this. We used open source software exclusively in our laboratory exercises and we provide the rationale behind our choice of specific software packages.
Developing and deploying software engineering courseware in an adaptable curriculum framework
Authors: W. Richards Adroin
Venue: Proceedings of the 22nd international conference on Software engineering (2000)

We describe an effort to design an adaptable framework for teaching and learning in software engineering. We are developing a repository of asynchronous, multimedia courseware that facilitates the rapid incorporation of new advances in research and technology, enables courses to be tailored to individual student needs and interests, leverages innovations in educational technology and encourages innovation in teaching and in student learning. Our emphasis is on developing composable multi-level &ldquo;knowledge and topic units&rdquo; (KU/TUs) that can be employed to tailor course content and depth to fit the needs of a diverse student population. We have developed &ldquo;live&rdquo; and on-line course material for KU/TUs in software engineering and taught courses using this material. The framework was deployed in three software engineering courses (previously taught concurrently) and provides quite different learning environments for the students in each course and, to some extent, tailors the courses to individual students within the classes based on their skills, objectives and backgrounds. We describe efforts at formative evaluation. Student satisfaction is high and available measures of success, e.g., student performance, have improved markedly. We also describe a project now beginning to build on this prototype that will be accompanied by more extensive formative and summative evaluation.
Stability of long-lived consensus (extended abstract)
Authors: Shlomi Dolev, Sergio Rajsbaum
Venue: Proceedings of the nineteenth annual ACM symposium on Principles of distributed computing (2000)

This paper introduces the notion stability for a long-lived consensus system. This notion reflects how sensitive to changes the decisions of the system are, from one invocation of the consensus algorithm to the next, with respect to input changes. Stable long-lived consensus systems are proposed, and tight lower bounds on the achievable stability are proved, for several different scenarios. The scenarios include systems that keep memory from one invocation of consensus to the next versus memoryless systems; systems that take their decisions based on the number of different inputs but not on the source identities of those inputs versus non-symmetric systems. These results intend to study essential aspects of stability, and hence are independent of specific models of distributed computing. Applications to particular asynchronous and synchronous system are described.
Gender and programming: what's going on?
Authors: Janet Carter, Tony Jenkins
Venue: Proceedings of the 4th annual SIGCSE/SIGCUE ITiCSE conference on Innovation and technology in computer science education (1999)

The learning (and teaching) of programming in Higher Education is a perennial problem, and is the subject of much attention and innovation.One way in which the problem can be addressed is for instructors to investigate and thus better understand the ways in which students learn to program.We present the results of investigations carried out at the Universities of Kent and Leeds into the ways in which gender influences the learning approach of students in programming. The research shows that gender is a significant factor in determining the way in which students approach learning to program. A better understanding of the issues raised would lead to more effective teaching and thus better learning.
A Gap in GRM Code Weight Distributions
Authors: Todd D. Vance
Venue: Designs, Codes and Cryptography (2000)

The weight distribution of GRM (generalized Reed-Muller) codes is unknown in general. This article describes and applies some new techniques to the codes over \gf{3}. Specifically, we decompose GRM codewords into words from smaller codes and use this decomposition, along with a projective geometry technique, to relate weights occurring in one code with weights occurring in simpler codes. In doing so, we discover a new gap in the weight distribution of many codes. In particular, we show there is no word of weight 3^{m-2} in \grm_3(4,m) for m>6, and for even-order codes over the ternary field, we show that under certain conditions, there is no word of weight d+\Delta, where d is the minimum distance and \Delta is the largest integer dividing all weights occurring in the code.
Testing levels for object-oriented software
Authors: Y. Labiche, P. Thévenod-Fosse, H. Waeselynck, M.-H. Durand
Venue: Proceedings of the 22nd international conference on Software engineering (2000)

One of the characteristics of object-oriented software is the complex dependency that may exist between classes due to inheritance, association and aggregation relationships. Hence, where to start testing and how to define an integration strategy are issues that require further investigation. This paper presents an approach to define a test order by exploiting a model produced during design stages (e.g., using OMT, UML), namely the class diagram. Our goal is to minimize the number of stubs to be constructed in order to decrease the cost of testing. This is done by testing a class after the classes it depends on. The novelty of the test order lies in the fact that it takes account of: (i) dynamic (polymorphism) dependencies; (ii) abstract classes that cannot be instantiated, making some testing levels infeasible. The test order is represented by a graph showing which testing levels must be done in sequence and which ones may be done independently. It also provides information about the classes involved in each level and how they are involved (e.g., instantiation or not). The approach is implemented in a tool called TOONS (Testing level generator for Object-OrieNted Software). It is applied to an industrial case study from the avionics domain.
Relational programs
Authors: Farokh B. Bastani
Venue: ACM SIGSOFT Software Engineering Notes (2000)

The objective of this research is to produce useful, low-cost methods for developing correct concurrent programs from formal specifications. In particular, we address the design and verification of the synchronization and communication portions of such programs. Often, this portion can be implemented using a fixed, finite amount of synchronization related data, i.e., it is "finite-state." Nevertheless, even when each program component contains only one bit of synchronization related data, the number of possible global synchronization states for K components is about 2K, in general. Because of this "state-explosion" phenomenon, the manual verification of large concurrent programs typically requires lengthy, and therefore error-prone, proofs. Using a theorem prover increases reliability, but requires extensive formal labor to axiomatize and solve verification problems. Automatic verification methods (such as reachability analysis and temporal logic model checking) use state-space exploration to decide if a program satisfies its specification, and are therefore also subject to state-explosion. To date, proposed techniques for ameliorating state-explosion either require significant manual labor, or work well only when the program is highly symmetric and regular (e.g., many functionally similar components connected in similar ways).To overcome these drawbacks, we advocate the synthesis of programs from specifications. This approach performs the refinement from specifications to programs automatically. Thus, the amount of formal labor is reduced to writing a formal specification and applying the appropriate synthesis step at each stage of the derivation. While nontrivial, writing a formal specification is necessary in any methodology that guarantees correctness.
Optimal Reconstruction of Natural Images by Small Setsof Gabor Filters
Authors: J. H. Van Deemter, G. Cristobal
Venue: Multidimensional Systems and Signal Processing (1998)

Images can be reconstructed after being filtered by a Gaussian and a few Gabor filters. Several search methods for the filter parameters for a (near) optimal reconstruction are examined. At first, the search is performed on a 1-D signal which satisfies the radial spectrum of the average of natural images. Later, these results are extended and applied to a 2-D example. It is shown that the resulting parameters are better than those of some existing models.
The Hotbox: efficient access to a large number of menu-items
Authors: Gordon Kurtenbach, George W. Fitzmaurice, Russell N. Owen, Thomas Baudel
Venue: Proceedings of the SIGCHI conference on Human factors in computing systems: the CHI is the limit (1999)

The proliferation of multiple toolbars and UI widgets around the perimeter of application windows is an indication that the traditional GUI design of a single menubar is not sufficient to support large scale applications with numerous functions. In this paper we describe a new widget which is an enhancement of the traditional menubar which dramatically increases menu-item capacity. This widget, called the Hotbox combines several GUI techniques which are generally used independently: accelerator keys, modal dialogs, pop-up/pull down menus, radial menus, marking menus and menubars. These techniques are fitted together to create a single, easy to learn yet fast to operate GUI widget which can handle significantly more menu-items than the traditional GUI menubar. We describe the design rationale of the Hotbox and its effectiveness in a large scale commercial application. While the Hotbox was developed for a particular application domain, the widget itself and the design rationale are potentially useful in other domains.
DTD inference for views of XML data
Authors: Yannis Papakonstantinou, Victor Vianu
Venue: Proceedings of the nineteenth ACM SIGMOD-SIGACT-SIGART symposium on Principles of database systems (2000)

We study the inference of Data Type Definitions (DTDs) for views of XML data, using an abstraction that focuses on document content structure. The views are defined by a query language that produces a list of documents selected from one or more input sources. The selection conditions involve vertical and horizontal navigation, thus querying explicitly the order present in input documents. We point several strong limitations in the descriptive ability of current DTDs and the need for extending them with (i) a subtyping mechanism and (ii) a more powerful specification mechanism than regular languages, such as context-free languages. With these extensions, we show that one can always infer tight DTDs, that precisely characterize a selection view on sources satisfying given DTDs. We also show important special cases where one can infer a tight DTD without requiring extension (ii). Finally we consider related problems such as verifying conformance of a view definition with a predefined DTD. Extensions to more powerful views that construct complex documents are also briefly discussed.
A High-Order Iterative Implicit-Explicit Hybrid Scheme for Magnetohydrodynamics
Authors: Wenlong Dai, Paul R. Woodward
Venue: SIAM Journal on Scientific Computing (1998)

An iterative implicit-explicit hybrid scheme is proposed for one-dimensional ideal magnetohydrodynamical (MHD) equations. The scheme is accurate to second order in both space and time for all Courant numbers. Each kind of MHD wave, both compressible and incompressible, may be either implicitly or explicitly, or partially implicitly and partially explicitly treated depending on their associated Courant numbers in each numerical cell, and the scheme is able to smoothly switch between explicit and implicit calculations. The scheme is of Godunov type in both explicit and implicit regimes, in which the flux needed in a Godunov scheme is calculated from Riemann problems, is in a strictly conservation form, and is able to resolve MHD discontinuities. Only a single level of iterations is involved in the scheme, and the iterations solve both the implicit relations arising from upstream centered differences for all wave families and the nonlinearity of MHD equations. Multicolors proposed in the paper may significantly reduce the number of iterations required to reach a converged solution. Compared with the largest Courant number in a simulation, only a small number of iterations are needed in the scheme. The feature of the scheme has been shown through numerical examples. It is easy to vectorize the computer code of the scheme.
A Region-Based Representation of Images in MARS
Authors: Sergio D. Servetto, Yong Rui, Kannan Ramchandran, Thomas S. Huang
Venue: Journal of VLSI Signal Processing Systems (1998)

We study the problem of representing images within a multimedia Database Management System (DBMS), in order to support fast retrieval operations without compromising storage efficiency. To achieve this goal, we propose new image coding techniques which combine a wavelet representation, embedded coding of the wavelet coefficients, and segmentation of image-domain regions in the wavelet domain. A bitstream is generated in which each image region is encoded independently of other regions, without having to explicitly store information describing the regions. Simulation results show that our proposed algorithms achieve coding performance which compares favorably, both perceptually and objectively, to that achieved using state-of-the-art image/video coding techniques while additionally providing region-based support.