ppxscal/embedding_network huggingface dataset:
Fundamental results on the performance of ATM multiplexers with applications to video teleconferencing
Authors: Anwar Elwalid, Daniel Heyman, T. V. Lakshman, Debasis Mitra, Alan Weiss
Venue: Proceedings of the 1995 ACM SIGMETRICS joint international conference on Measurement and modeling of computer systems (1995)

The main contributions of this paper are two-fold. First, we prove fundamental, similarly behaving lower and upper bounds, and give an approximation based on the bounds, which is effective for analyzing ATM multiplexers, even when the traffic has many, possibly heterogeneous, sources and their models are of high dimension. Second, we apply our analytic approximation to statistical models of video teleconference traffic, obtain the multiplexing system's capacity as determined by the number of admissible sources for given cell loss probability, buffer size and trunk bandwidth, and, finally, compare with results from simulations, which are driven by actual data from coders. The results are surprisingly close. Our bounds are based on Large Deviations theory. Our approximation has two easily calculated parameters, one is from Chernoff's theorem and the other is the system's dominant eigenvalue. A broad range of systems are analyzed and the time for analysis in each case is a fraction of a second.
An investigation of the relationship between student algorithm quality and program quality
Authors: Tanya McGill, Simone Volet
Venue: ACM SIGCSE Bulletin (1995)

This paper reports on an exploratory study designed to explore the relationship between the quality of students' algorithm development and the quality of their final programs. By videotaping pairs of students engaged in writing a program to solve a problem the process used by students could be examined and its relationship to program quality investigated. The results of the study show a clear positive relationship between the quality of algorithm development and the quality of programs written by students in an introductory programming course.
Computing Minimal Spanning Subgraphs in Linear Time
Authors: Xiaofeng Han, Pierre Kelsen, Vijaya Ramachandran, Robert Tarjan
Venue: SIAM Journal on Computing (1995)

Let $P$ be a property of undirected graphs. We consider the following problem: given a graph $G$ that has property $P$, find a minimal spanning subgraph of $G$ with property $P$. We describe general algorithms for this problem and prove their correctness under fairly weak assumptions about $P$. We establish that the worst-case running time of these algorithms is $\Theta(m+n \log n)$ for 2-edge-connectivity and biconnectivity where $n$ and $m$ denote the number of vertices and edges, respectively, in the input graph. By refining the basic algorithms we obtain the first linear time algorithms for computing a minimal 2-edge-connected spanning subgraph and for computing a minimal biconnected spanning subgraph. We also devise general algorithms for computing a minimal spanning subgraph in directed graphs. These algorithms allow us to simplify an earlier algorithm of Gibbons, Karp, Ramachandran, Soroker, and Tarjan for computing a minimal strongly connected spanning subgraph. We also provide the first tight analysis of the latter algorithm, showing that its worst-case time complexity is $\Theta(m+n \log n).$
Reuse through inheritance: a quantitative study of C++ software
Authors: James M. Bieman, Josephine Xia Zhao
Venue: ACM SIGSOFT Software Engineering Notes (1995)

According to proponents of object-oriented programming, inheritance is an excellent way to organize abstraction and a superb tool for reuse. Yet, few quantitative studies of the actual use of inheritance have been conducted. Quantitative studies are necessary to evaluate the actual usefulness of structures such as inheritance. We characterize the use of inheritance in 19 existing C++ software systems containing 2,744 classes. We measure the class depth in the inheritance hierarchies, and the number of child and parent classes in the software. We find that inheritance is used far less frequently than expected.
The Chinook hardware/software co-synthesis system
Authors: Pai H. Chou, Ross B. Ortega, Gaetano Borriello
Venue: Proceedings of the 8th international symposium on System synthesis (1995)

Abstract: Designers of embedded systems are facing ever tighter constraints on design time, but computer-aided design tools for embedded systems have not kept pace with these trends. The Chinook co-synthesis system addresses the automation of the most time-consuming and error-prone tasks in embedded controller design, namely the synthesis of interface hardware and software needed to integrate system components, the migration of functions between processors or custom logic, and the co-simulation of the design before, during and after synthesis. This paper describes the principal elements of Chinook and discuss its application to a variety of embedded designs.
Provably correct theories of action
Authors: Fangzhen Lin, Yoav Shoham
Venue: Journal of the ACM (JACM) (1995)

We investigate logical formalization of the effects of actions in the situation calculus. We propose a formal criterion against which to evaluate theories of deterministic actions. We show how the criterion provides us a formal foundation upon which to tackle the frame problem, as well as its variant in the context of concurrent actions. Our main technical contributions are in formulating a wide class of monotonic causal theories that satisfy the criterion, and showing that each such theory can be reformulated succinctly in circumscription.
Solar Cars and Variational Problems Equivalent to Shortest Paths
Authors: D. J. Gates, M. Westcott
Venue: SIAM Journal on Control and Optimization (1996)

A classical theorem of Hardy, Littlewood, and Polya on rearrangements of functions is used to prove the equivalence of a class of variational problems. As a consequence, solutions are shortest paths and can be computed numerically via quadratic programming. Applications include solar cars and reservoirs.
Linear recurrences with carry as uniform random number generators
Authors: Raymond Couture, Pierre L'Ecuyer
Venue: Proceedings of the 27th conference on Winter simulation (1995)

We study the multiply-with-carry family of generators proposed by G. Marsaglia (1994) as a generalisation of the previous add-with-carry and subtract-with-borrow families of G. Marsaglia and A. Zaman (1991). We define for them a general (infinite) state space and focus our attention on the (finite) subset of recurrent states. This subset will, in turn, split into possibly several subgenerators. We discuss the uniformity of the d-dimensional distribution of the output of these subgenerators over their full period. In order to improve this uniformity for higher dimensions, we propose a method for finding good parameters in terms of the spectral test.
Wireless client/server computing for personal information services and applications
Authors: Ahmed Elmagarmid, Jin Jing, Tetsuya Furukawa
Venue: ACM SIGMOD Record (1995)

We are witnessing a profound change in the global information infrastructure that has the potential to fundamentally impact many facets of our life. An important aspect of the evolving infrastructure is the seamless, ubiquitous wireless connectivity which engenders continuous interactions between people and interconnected computers. A challenging area of future ubiquitous wireless computing is the area of providing mobile users with integrated Personal Information Services and Applications (PISA). In this paper, a wireless client/server computing architecture will be discussed for the delivery of PISA. Data management issues such as transactional services and cache consistency will be examined under this architecture.
Equal access to information for all: making the world of electronic information more accessible to the handicapped in our society
Authors: Arthur I. Karshmer, Karlis Kaugars
Venue: Issue 52-53 (November 1995) (1995)

On March 27th, 1995, the World Wide Web and the information super highway took a big step on the road to becoming the new window into the world of information. On that date MCI began its InternetMCI service. The net surfer can now shop, get critical information and news, get investment advice and much more. And this is only the first step. By a series of simple mouse clicks, the user has almost instant access to services and products almost anywhere in the world.The use of modern computers and software by the visually handicapped has become more difficult over the past few years. In earlier systems the user interface was a simple character based environment. In those systems, simple devices like screen readers, braille output and speech synthesizers were effective. Current systems now run Graphical User Interfaces (GUIs) which have rendered these simple aids almost useless. In no area has this problem become more important than in technologies for the handicapped. What has become enabling technology for the sighted has become disabling technology for the visually impaired.
Using Persistent Excitation with Fixed Energy to Stabilize AdaptiveControllers and Obtain Hard Bounds for the Parameter Estimation Error
Authors: Miloje S. Radenkovic, B. Erik Ydstie
Venue: SIAM Journal on Control and Optimization (1995)

Two important instability problems in certainty equivalence adaptive control are solved by external excitation. The first instability is parameter drift along an unstable manifold when the excitation level is not high enough. The second instability is numerical and due to a division with zero in the adaptive law. Global methods based on excitation have been developed to solve this problem, but the energy of the excitation has been tuned on-line. The main contribution of the current paper is in showing that the estimator is stabilized when we apply excitation with fixed and finite energy. The level of excitation should be sufficiently high relative to the magnitudes of the external disturbances and the unmodeled dynamics. The approach can be generalized to more complex adaptive laws. This, together with the fact that we obtain hard bounds for the parameter estimation error, opens up for the possibility of designing robust controllers that are adaptive.
Protocol architecture for multimedia applications over ATM networks
Authors: Dilip D. Kandlur, Debanjan Saha, M. Willebeek-LeMair
Venue: ACM SIGCOMM Computer Communication Review (1995)

At the data-link layer, ATM offers a number of features, such as high-bandwidth and per-connection quality of service (QoS) guarantees, making it particularly attractive to multimedia applications. Unfortunately, many of these features are not visible to applications because of the inadequacies of existing higher-level protocol architectures. Although a considerable effort is underway to tune these protocols for ATM networks, we believe that a new ATM specific protocol stack is essential to effectively exploit all the benefits of ATM. In this paper we describe the semantics of such a protocol stack, and discuss its advantages over traditional protocol architectures from the perspective of distributed multimedia applications. The performance impact of the new protocol architecture is experimentally demonstrated on a video conferencing testbed built around IBM RS/6000s equipped with prototype hardware for video/audio processing, and connected via ATM links.
The integration of virtual memory management and interprocess communication in Accent
Authors: Robert Fitzgerald, Richard F. Rashid
Venue: ACM Transactions on Computer Systems (TOCS) (1986)

The integration of virtual memory management and interprocess communication in the Accent network operating system kernel is examined. The design and implementation of the Accent memory management system is discussed and its performance, both on a series of message-oriented benchmarks and in normal operation, is analyzed in detail.
Supporting distributed office problem solving in organizations
Authors: Carson C. Woo, Frederick H. Lochovsky
Venue: ACM Transactions on Information Systems (TOIS) (1986)

To improve the effectiveness of office workers in their decision making, office systems have been built to support (rather than replace) their judgment. However, these systems model office work in a centralized environment, and/or they can only support a single office worker. Office work that is divided into specialized domains handled by different office workers (where cooperation is needed in order to accomplish the work) is not supported. In this paper, we will present a model that supports office problem solving in a logically distributed environment. (In some systems, information is geographically distributed for performance purposes rather than for conceptual need. The term, logically, is therefore used to indicate the logical need of organizing information without having to worry about the physical location of the information.) In particular, cooperative tools that can be used to support office workers during the process of their problem solving is discussed.
Numerical Approximation of the One-Dimensional Vlasov--Poisson System with Periodic Boundary Conditions
Authors: Stephen Wollman, Ercument Ozizmir
Venue: SIAM Journal on Numerical Analysis (1996)

A particle method of approximation is given for the one-dimensional Vlasov--Poisson system with periodic boundary conditions. The method is proved to converge without mollification of the electric field as the interparticle distance and time step are made small. A numerical study is carried out to verify the theory and further study convergence properties of the computed solution.
Semicirculant Solvers and Boundary Corrections for First-Order Partial Differential Equations
Authors: Sverker Holmgren, Kurt Otto
Venue: SIAM Journal on Scientific Computing (1996)

Fast solvers for systems of partial differential equations (PDEs) in two space dimensions are considered. The solvers are used as direct solution methods or as preconditioners for a conjugate gradient (CG)-like iteration. Mainly first-order PDEs are considered, but second-order terms may be included. Employing a semicirculant framework, PDEs with constant coefficients in one space direction and arbitrary boundary conditions are considered. A factorization of the inverse of the difference approximation matrix is described. This factorization is exploited to derive a direct solver, where the complexity for the first right-hand side is ${\cal O}(n^{3/2}\log_2n)$, but only ${\cal O}(n\log_2n)$ for subsequent right-hand sides. From the factorization an iteration resembling the Schur complement matrix method known from domain decomposition is also constructed. The eigendecomposition of the iteration matrix is investigated. The new solution methods are compared with iterations with semicirculant preconditioners and to Gaussian elimination. An application solving the time-dependent, almost incompressible Navier--Stokes equations is also studied.
pC++/streams: a library for I/O on complex distributed data sources
Authors: Jacob Gotwals, Suresh Srinivas, Dennis Gannon
Venue: ACM SIGPLAN Notices (1995)

The design and implementation of portable, efficient, and expressive mechanisms for I/O on complex distributed data structures&mdash;such as found in adaptive parallel applications&mdash;is a challenging problem that we address in this paper.We describe the design, programmer interface, implementation, and performance of pC++/streams, a library that provides an expressive mechanism for I/O on distributed arrays of variable-sized objects in pC++, an object-parallel language. pC++/streams is intended for developers of parallel programs requiring efficient high-level I/O abstractions for checkpointing, scientific visualization, and debugging.pC++/streams is an implementation of d/streams, a language-independent abstraction for buffered I/O on distributed data structures. We describe the d/streams abstraction and present performance results on the Intel Paragon and SGI Challenge showing that d/streams can be implemented efficiently and portably.
A taxonomy of domain-specific reuse problems and their resolutions&mdash;version 1.0
Authors: Wing Lam, Ben Whittle
Venue: ACM SIGSOFT Software Engineering Notes (1996)

This paper presents a taxonomy of problems related to domain-specific reuse. The taxonomy identifies seven major problem categories (such as domain, modeling notation and viewpoints) and their sub-categories. A description of each problem in the taxonomy is given, illustrated where appropriate, with an example taken from an industrial case-study performed by the authors for Rolls-Smiths Engine Controls Limited (RoSEC). A resolution matrix is also presented, which suggests practical strategies for resolving each kind of problem described in the taxonomy.
Software aspects of strategic defense systems
Authors: David Lorge Parnas
Venue: Communications of the ACM (1985)

A former member of the SDIO Panel on Computing in Support of Battle Management explains why he believes the &ldquo;Star Wars&rdquo; effort will not achieve its stated goals.
A Schur Method for Low-Rank Matrix Approximation
Authors: Alle-Jan vander Veen
Venue: SIAM Journal on Matrix Analysis and Applications (1996)

The usual way to compute a low-rank approximant of a matrix $H$ is to take its singular value decomposition (SVD) and truncate it by setting the small singular values equal to 0. However, the SVD is computationally expensive. This paper describes a much simpler generalized Schur-type algorithm to compute similar low-rank approximants. For a given matrix $H$ which has $d$ singular values larger than $\epsilon$, we find all rank $d$ approximants $\Ha$ such that $H - \Ha$ has 2-norm less than $\epsilon$. The set of approximants includes the truncated SVD approximation. The advantages of the Schur algorithm are that it has a much lower computational complexity (similar to a QR factorization), and directly produces a description of the column space of the approximants. This column space can be updated and downdated in an on-line scheme, amenable to implementation on a parallel array of processors.
Exceptions and exception handling in computerized information processes
Authors: Diane M. Strong, Steven M. Miller
Venue: ACM Transactions on Information Systems (TOIS) (1995)

Exceptions, situations that cannot be correctly processed by computer systems, occur frequently in computer-based information processes. Five perspectives on exceptions provide insights into why exceptions occur and how they might be eliminated or more efficiently handled. We investigate these perspectives using an in-depth study of an operating information process that has frequent exceptions. Our results support the use of a total quality management (TQM) approach of eliminating exceptions for some exceptions, in particular, those caused by computer systems that are poor matches to organizational processes. However, some exceptions are explained better by a political system perspective of conflicting goals between subunits. For these exceptions and several other types, designing an integrated human-computer process will provide better performance than will eliminating exceptions and moving toward an entirely automated process.
Building end user applications with extend
Authors: David Krahl
Venue: Proceedings of the 27th conference on Winter simulation (1995)

The article presents an overview of the Extend modeling environment, emphasizing Extend's features for building a custom user interface. Extend is a graphically oriented discrete event and continuous simulation application with an integrated authoring environment.
Goals and processes: a task basis for projects and workflows
Authors: Noël Craven, Dirk Mahling
Venue: Proceedings of conference on Organizational computing systems (1995)

This paper focuses on the set of group endeavors that exists within the structure of an organization. The environment in which organizations exist is becoming increasingly dynamic. Cooperative tasks are increasing and workgroup computing is becoming more pervasive. There are computer-mediated tools and systems to support organizations' coordination of group endeavors. These systems, however, are incomplete and therefore do not adequately give organizations the flexibility that a dynamic environment requires. The need for unified information systems is looming. The solution is to provide consistent and comprehensive, computer-mediated, shared task support for the coordination of group endeavors in all domains, in dynamic, and increasingly complex environments. Workflow and project management are prototypical of that collaborative use. This paper evaluates workflow processes and projects in order to gain an understanding of requirements that will serve as a conceptual foundation for this cooperative systems environment.
Perturbations, Singular Values, and Ranks of Partial Triangular Matrices
Authors: Leiba Rodman, Hugo J. Woerdeman
Venue: SIAM Journal on Matrix Analysis and Applications (1995)

Questions regarding minimal representations of perturbations of discrete systems lead to the study of perturbations of lower triangular partial matrices and their minimal rank completions. Distance to the set of lower triangular partial matrices having minimal ranks smaller than a given integer is given in terms of (suitably generalized) singular numbers. Minimal ranks of lower triangular partial matrices in an arbitrary small neighborhood of a given lower triangular partial matrix are identified. The results are applied to minimal representations of discrete systems.
Pen computing: a technology overview and a vision
Authors: André Meyer
Venue: ACM SIGCHI Bulletin (1995)

This work gives an overview of a new technology that is attracting growing interest in public as well as in the computer industry itself. The visible difference from other technologies is in the use of a pen or pencil as the primary means of interaction between a user and a machine, picking up the familiar pen and paper interface metaphor. From this follows a set of consequences that will be analyzed and put into context with other emerging technologies and visions.Starting with a short historical background and the technical advances that begin making Pen Computing a reality, the new paradigms created by Pen Computing will be explained and discussed. Handwriting recognition, mobility and global information access are other central topics. This is followed by a categorization and an overview of current and future systems using pens as their primary user interface component.
Algorithm 747: a Fortran subroutine to solve the eigenvalue assignment problem for multiinput systems using state feedback
Authors: George Miminis, Helmut Roth
Venue: ACM Transactions on Mathematical Software (TOMS) (1995)

The implementation of an algorithm for the computation of a state feedback for multiinput linear systems, resulting in a closed-loop matrix with a specified self-conjugate set of eigenvalues, is presented. The computation uses only real arithmetic, assigning complex conjugate eigenvalues in one double step. The implementation uses level-1 BLAS routines where possible. A brief description of the algorithm is also given.
Necessary and Sufficient Conditions for Consistent Global Snapshots
Authors: Robert H. B. Netzer, Jian Xu
Venue: IEEE Transactions on Parallel and Distributed Systems (1995)

Consistent global snapshots are important in many distributed applications. We prove the exact conditions for an arbitrary checkpoint, or a set of checkpoints, to belong to a consistent global snapshot, a previously open problem. To describe the conditions, we introduce a generalization of Lamport's happened-before relation called a zigzag path.Index Terms¿Causality, global checkpoints, distributed systems, consistent global states, Lamport's happened-before relation.