ppxscal/embedding_network huggingface dataset:
Multi-way system partitioning into a single type or multiple types of FPGAs
Authors: Dennis J.-H. Huang, Andrew B. Kahng
Venue: Proceedings of the 1995 ACM third international symposium on Field-programmable gate arrays (1995)

This paper considers the problem of partitioning a circuit into a collection of subcircuits, such that each subcircuit is feasible for some device from an FPGA library, and the total cost of devices is minimized. We propose a three-phase heuristic that uses ordering, clustering, and dynamic programming to achieve good solutions. Experimental comparisons are made with the previous methods of [4][9].
Greengard's N-Body Algorithm is Not Order N
Authors: Srinivas Aluru
Venue: SIAM Journal on Scientific Computing (1996)

Greengard's $N$-body algorithm claims to compute the pairwise interactions in a system of $N$ particles in $O(N)$ time for a fixed precision. In this paper, we show that the choice of precision is not independent of $N$ and has a lower bound of $\log N$. We use this result to show that Greengard's algorithm is not $O(N)$.
Some New Designs of 2-D Array for Matrix Multiplication and Transitive Closure
Authors: Jong-Chuang Tsay, Pen-Yuang Chang
Venue: IEEE Transactions on Parallel and Distributed Systems (1995)

In this paper, we present some new regular iterative algorithms for matrix multiplication and transitive closure. With these algorithms, by spacetime mapping the 2-D arrays with $2N - 1$ and $\lceil (3N - 1)/2\rceil$ execution times for matrix multiplication can be obtained. Meanwhile, we can derive a 2-D array with $4N - 2$ execution time for transitive closure based on the sequential Warshall-Floyd algorithm. All these new 2-D arrays for matrix multiplication and transitive closure have the advantages of faster and more regular than other previous designs.Index Terms¿Algorithm mapping, matrix multiplication, mesh array, systolic array, spherical array, transitive closure, VLSI architecture.
Going Beyond Integer Programming with the Omega Test to Eliminate False Data Dependences
Authors: William Pugh, David Wonnacott
Venue: IEEE Transactions on Parallel and Distributed Systems (1995)

Array data dependence analysis methods currently in use generate false dependences that can prevent useful program transformations. These false dependences arise because the questions asked are conservative approximations to the questions we really should be asking. Unfortunately, the questions we really should be asking go beyond integer programming and require decision procedures for a subclass of Presburger formulas. In this paper, we describe how to extend the Omega test so that it can answer these queries and allow us to eliminate these false data dependences. We have implemented the techniques described here and believe they are suitable for use in production compilers.
Texture Features for Browsing and Retrieval of Image Data
Authors: B. S. Manjunath, W. Y. Ma
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (1996)

Image content based retrieval is emerging as an important research area with application to digital libraries and multimedia databases. The focus of this paper is on the image processing aspects and in particular using texture information for browsing and retrieval of large image data. We propose the use of Gabor wavelet features for texture analysis and provide a comprehensive experimental evaluation. Comparisons with other multiresolution texture features using the Brodatz texture database indicate that the Gabor features provide the best pattern retrieval accuracy. An application to browsing large air photos is illustrated.
Specification matching for software reuse: a foundation
Authors: Jun-Jang Jeng, Betty H. C. Cheng
Venue: ACM SIGSOFT Software Engineering Notes (1995)

Using formal specifications to represent software components facilitates the determination of reusability because they more precisely characterize the functionality of the software, and the well-defined syntax makes processing amenable to automation. We present specification matching as a method for classification, retrieval, and modification of reusable components. A software component is specified in terms of order-sorted predicate logic. For both components and methods, we consider not only exact match, but also relaxed match and logical match for peforming specification matching over a library of reusable software components.
An Essay on the Ree Octagons
Authors: M. Joswig, H. Van Maldeghem
Venue: Journal of Algebraic Combinatorics: An International Journal (1995)

We coordinatize the Moufang generalized octagons arising from the Ree groups of type 2F4. In this way, we obtain a very concrete and explicit description of these octagons. We use this to prove some results on suboctagons, generalized homologies, Suzuki-Tits ovoids and groups of projectivities of the Ree octagons. All our results hold for arbitrary Ree octagons, finite or not.
Attractors and Error Estimates for Discretizations of Incompressible Navier--Stokes Equations
Authors: Yin Yan
Venue: SIAM Journal on Numerical Analysis (1996)

By embedding sets of nodal values to function spaces, variational arguments are applied to the finite difference approximations to the two-dimensional incompressible Navier--Stokes equations. The error estimates for trajectories and the {\it time-free} error estimates with tolerance for attractors are proved. The upper semicontinuity of the attractors with respect to the finite difference discretizations are also proved. Arguments of applying the techniques to the finite element approximations are also given.
On extending parallelism to serial simulators
Authors: David Nicol, Philip Heidelberger
Venue: Proceedings of the ninth workshop on Parallel and distributed simulation (1995)

This paper describes an approach to discrete event simulation modeling that appears to be effective for developing portable and efficient parallel execution of models of large distributed systems and communication networks. In this approach, the modeler develops sub-models using an existing sequential simulation modeling tool, using the full expressive power of the tool. A set of modeling language extensions permit automatically synchronized communication between sub-models; however, the automation requires that any such communication must take a non-zero amount of simulation time. Within this modeling paradigm, a variety of conservative synchronization protocols can transparently support conservative execution of sub-models on potentially different processors. A specific implementation of this approach, U.P.S. (Utilitarian Parallel Simulator), is described, along with performance results on the Intel Paragon.
Partitioning for synchronous parallel simulation
Authors: Pavlos Konas, Pen-Chung Yew
Venue: Proceedings of the ninth workshop on Parallel and distributed simulation (1995)

A new partitioning method for synchronous PDES simulations is proposed. The method exploits characteristics of both the simulation method and of the application domain to arrive at efficient partitionings. A performance study shows that the method outperforms existing partitioning methods in terms of four different performance metrics.
A new emphasis pedagogy for a CS1 course
Authors: M. D. Evans
Venue: ACM SIGCSE Bulletin (1996)

A CS1 course introduces students to fundamental aspects of computing science. Invariably, these aspects are ones of content (subject matter). There is an alternative, and arguably more beneficial, role for a CS1 course - it could introduce the fundamental processes and concepts which pervade all computing science content domains, and which have but different instantiations in the different domains. This article considers the identification of these aspects, and suggests a pedagogy suitable for their emphasis. This pedagogy is applied to a traditional CS1 programming-content domain, resulting in a proposal for a new CS1 curriculum.
The Sublogarithmic Alternating Space World
Authors: Maciej Liskiewicz, Rüdiger Reischuk
Venue: SIAM Journal on Computing (1996)

This paper tries to fully characterize the properties and relationships of space classes defined by Turing machines that use less than logarithmic space -- may they be deterministic, nondeterministic or alternating (DTM, NTM, or ATM). We provide several examples of specific languages and show that such machines are unable to accept these languages. The basic proof method is a nontrivial extension of the $1^n \mapsto 1^{n+n!}$ technique to alternating TMs. Let $\llog$ denote the logarithmic function $\log$ iterated twice, and $\SSS{k}$, $\PSS{k}$ be the complexity classes defined by $S$--space-bounded ATMs that alternate at most $k-1$ times and start in an existential, resp. universal state. Our first result shows that for each $k > 1$ the sets \begin{eqnarray*} \SSl{k} &\setminus& \PSu{k} \quad \hbox{ and} \\ \PSl{k} &\setminus& \SSu{k} \end{eqnarray*} are both not empty. This implies that for each $S \in \Omega(\llog ) \cap o(\log )$ the classes \begin{eqnarray*} \SSS{1} &\spna& \SSS{2} \spna \SSS{3} \spna \ldots \\ &\spna & \SSS{k} \spna \SSS{k+1} \spna \ldots \end{eqnarray*} form an infinite hierarchy. Furthermore, this separation is extended to space classes defined by ATMs with a nonconstant alternation bound $A$ provided that the product $A \* S$ grows sublogarithmically. These lower bounds can also be used to show that basic closure properties do not hold for such classes. We obtain that for any $S \in \Omega(\llog ) \cap o(\log )$ and all $k > 1$ $\Sigma_k Space (S)$ and $\Pi_k Space (S)$ are not closed under complementation and concatenation. Moreover, $\Sigma_k Space (S)$ is not closed under intersection, and $\Pi_k Space (S)$ is not closed under union. \KURZ{ It is an interesting open question whether for sublogarithmic bounds $S$ the property that $\PSS{k}$ is the complement of $\SSS{k}$ is fulfilled. This is a nontrivial problem since there is no obvious way how to detect infinite computation paths. Here, } \KURZ{ we generalize Sipser's result on halting space-bound computations for sublogarithmic space bounded deterministic TMs \cite{S80} to } It is also shown that ATMs recognizing bounded languages can always be guaranteed to halt. For the class of $Z$--bounded languages with $Z \le \exp S$ we obtain the equality \( co\mbox{-}\SSS{k} \gla \PSS{k} \ . \) \KURZ{ We also consider the space requirement for the recognition of nonregular context-free languages. Alt, Geffert and Mehlhorn have recently shown a logarithmic lower bound for nondeterministic TMs \cite{AGM92}. We improve this result obtaining the same lower bound for ATMs. Thus this last result shows that even alternations do not increase the power of sublogarithmic machines substantially. } Finally, for sublogarithmic bounded ATMs we give a separation between the weak and strong space measure, and prove a logarithmic lower space bound for the recognition of nonregular context-free languages.
A Divide-and-Conquer Algorithm for the Symmetric TridiagonalEigenproblem
Authors: Ming Gu, Stanley C. Eisenstat
Venue: SIAM Journal on Matrix Analysis and Applications (1995)

The authors present a stable and efficient divide-and-conquer algorithm for computing the spectral decomposition of an $N \times N$ symmetric tridiagonal matrix. The key elements are a new, stable method for finding the spectral decomposition of a symmetric arrowhead matrix and a new implementation of deflation. Numerical results show that this algorithm is competitive with bisection with inverse iteration, Cuppen's divide-and-conquer algorithm, and the QR algorithm for solving the symmetric tridiagonal eigenproblem.
Optimal code generation for embedded memory non-homogeneous register architectures
Authors: Guido Araujo, Sharad Malik
Venue: Proceedings of the 8th international symposium on System synthesis (1995)

Abstract: This paper examines the problem of code generation for expression trees on non-homogeneous register set architectures. It proposes and proves the optimality of an O(n) algorithm for the tasks of instruction selection, register allocation and scheduling on a class of architectures defined as the [1,/spl infin/] model. Optimality is guaranteed by sufficient conditions derived from the register transfer graph (RTG), a structural representation of the architecture which depends exclusively on the processor instruction set architecture (ISA). Experimental results using the TMS320C25 as the target processor show the efficacy of the approach.
Observer-A Concept for Formal On-Line Validation of Distributed Systems
Authors: Michel Diaz, Guy Juanole, Jean-Pierre Courtiat
Venue: IEEE Transactions on Software Engineering (1994)

Proposes the observer concept for designing self-checking distributed systems, i.e. systems that detect erroneous behaviors as soon as errors act at some observable output level. The approach provides a solution to build systems whose on-line behavior is checked against a formal model derived from a formal description. In other words, the actual implementation is continuously checked against a reference, this reference being a formal and verified model of some adequately selected aspects of the system behavior. The corresponding methodology, the software concepts and some applications of the observer are presented. General definitions are given first that theoretically define self-checking systems as systems that include and implement complete on-line validation. The basic concepts and the difficulties to implement self-checking validation are then given. In order to provide simple implementations, the previous definitions are weakened to design quasi-self-checking observers for LANs using a broadcast service. Three specific applications are given to illustrate the proposed approach: testing a virtual ring MAC protocol, checking the link and transport layers in an industrial LAN, and managing a complete OSI layering, from layer 2 to layer 6, in an open system architecture.
Translation of nested APL to C++: problems and approaches
Authors: Dmitri Gusev, Igor Pospelov
Venue: Proceedings of the international conference on Applied programming languages (1995)

This paper discusses the task of developing a nested APL compiler and puts forward the project of such a compiler. The proposed approach consists of simulating the semantics of APL by using the object-oriented C++ programming language. Different kinds of problems ranging from APL syntax ambiguity to the implementation of nested arrays and the robustness of compiled code are considered and different solutions are proposed. We conclude that it is feasible to develop a robust nested APL compiler, although the problem of performance demands further research.
Multicast virtual topologies for collective communication in MPCs and ATM clusters
Authors: Y. Huang, C. C. Huang P. K. McKinley
Venue: Proceedings of the 1995 ACM/IEEE conference on Supercomputing (CDROM) (1995)

This paper defines and describes the properties of a multicast virtual topology, the M-array and a resource-efficient variation, the REM-array. It is shown how several collective operations can be implemented efficiently using these virtual topologies, while maintaining low complexity. Because the methods are applicable to any parallel computing environment that supports multicast communication in hardware, they provide a framework for collective communication libraries that are portable and yet take advantage of such low-level hardware functionality. In particular, the paper describes the practical issues of using these methods in wormhole-routed massively parallel computers (MPCs) and in workstation clusters connected by Asynchronous Transfer Mode (ATM) networks. Performance results are given for both environments.
An object-oriented file system&mdash;an example of using the class hierarchy framework concept
Authors: Tomas Smolik
Venue: ACM SIGOPS Operating Systems Review (1995)

This paper presents the design of an object-oriented file system which was developed as a part of the "OBJIX Object-Oriented Operating System" project. The file system is a self-contained program system which is decomposed using a standard object-oriented framework concept. A novel approach to object-oriented frameworks, the Class Hierarchy Framework concept recapitulated in this paper, is employed in structuring components of the file system. Further, this paper illustrates on an example how the file system pursues a typical system call.
User participation in information systems development techniques and tools
Authors: A. Guevara-Plaza, A. Aguayo-Maldonado, J. Falgueras-Cano, F. Triguero-Ruiz
Venue: ACM SIGOIS Bulletin (1995)

This work attempts to give a new direction to the analysis and design of Business Information Systems by substituting traditional techniques with more participatory techniques based on cooperation. In order to attain this objective, a review of organisational structures is suggested, as well as the use of cooperative methodology for the development of Information Systems. Equally, we propose the design and implementation of a set of cooperative tools which are characterised by an interface that allows end-user participation in the new phases of system creation.
On handling exceptions
Authors: Heikki Saastamoinen, George M. White
Venue: Proceedings of conference on Organizational computing systems (1995)

The current literature of information systems has dealt extensively with all kinds of exceptions. There are several studies defining the concept of exception and even providing classifications. However, no studies provide a method for verifying the rules in order to handle exceptions and to achieve the goals set by an organization's rules. In this paper, a model employing a set of unique input/output (UIO) sequences is presented for verifying such rules. The model originally presented for Finite State Machines (FSM) has been modified to include concepts of exception handling and will be used to form a tool usable for verifying exception handling rules in OISs.
Minimax Rendezvous on the Line
Authors: Wei Shi Lim, Steve Alpern
Venue: SIAM Journal on Control and Optimization (1996)

Suppose that $n$ players are placed randomly on the real line at consecutive integers, and faced in random directions. Each player has maximum speed one, cannot see the others, and doesn't know his relative position. What is the minimum time $M_n$ required to ensure that all the players can meet together at a single point, regardless of their initial placement? We prove that $M_2=3$, $M_3=4$, and $M_n$ is asymptotic to $n/2.$ We also consider a variant of the problem which requires players who meet to stick together, and find in this case that three players require $5$ time units to ensure a meeting. This paper is thus a minimax version of the rendezvous search problem, which has hitherto been studied only in terms of minimizing the expected meeting time.
Sixteen questions about software reuse
Authors: William B. Frakes, Christopher J. Fox
Venue: Communications of the ACM (1995)

Software reuse is the use of existing software knowledge or artifacts to build new software artifacts. Reuse is sometimes confused with porting. The two are distinguished as follows: Reuse is using an asset in different systems; porting is moving a system across environments or platforms. For example, in Figure 1 a component in System A is shown used again in System B; this is an example of reuse. System A, developed for Environment 1, is shown moved into Environment 2; this is an example of porting.
Preconditioning Reduced Matrices
Authors: Stephen G. Nash, Ariela Sofer
Venue: SIAM Journal on Matrix Analysis and Applications (1996)

We study preconditioning strategies for linear systems with positive-definite matrices of the form $Z^{T} GZ$, where $Z$ is rectangular and $G$ is symmetric but not necessarily positive definite. The preconditioning strategies are designed to be used in the context of a conjugate-gradient iteration, and are suitable within algorithms for constrained optimization problems. The techniques have other uses, however, and are applied here to a class of problems in the calculus of variations. Numerical tests are also included.
The MIT Alewife machine: architecture and performance
Authors: Anant Agarwal, Ricardo Bianchini, David Chaiken, Kirk L. Johnson, David Kranz, John Kubiatowicz, Beng-Hong Lim, Kenneth Mackenzie, Donald Yeung
Venue: ACM SIGARCH Computer Architecture News (1995)

Alewife is a multiprocessor architecture that supports up to 512 processing nodes connected over a scalable and cost-effective mesh network at a constant cost per node. The MIT Alewife machine, a prototype implementation of the architecture, demonstrates that a parallel system can be both scalable and programmable. Four mechanisms combine to achieve these goals: software-extended coherent shared memory provides a global, linear address space; integrated message passing allows compiler and operating system designers to provide efficient communication and synchronization; support for fine-grain computation allows many processors to cooperate on small problem sizes; and latency tolerance mechanisms --- including block multithreading and prefetching --- mask unavoidable delays due to communication.Microbenchmarks, together with over a dozen complete applications running on the 32-node prototype, help to analyze the behavior of the system. Analysis shows that integrating message passing with shared memory enables a cost-efficient solution to the cache coherence problem and provides a rich set of programming primitives. Block multithreading and prefetching improve performance by up to 25% individually, and 35% together. Finally, language constructs that allow programmers to express fine-grain synchronization can improve performance by over a factor of two.
Introduction to manufacturing applications
Authors: Gordon M. Clark
Venue: Proceedings of the 27th conference on Winter simulation (1995)

This tutorial introduces manufacturing applications of simulation through three illustrative example applications. These examples illustrate the additional understanding of system behavior gained by the use of simulation models. Individuals using simulation should use a structured process in applying simulation. The second example illustrates this structured process. The examples also illustrate the use of both stochastic and deterministic variables in modeling manufacturing systems.
On the Adaptive Control for Jump Parameter Systems viaNonlinear Filtering
Authors: Peter E. Caines, Ji-Feng Zhang
Venue: SIAM Journal on Control and Optimization (1995)

In this paper we first present an error analysis for the process of estimates generated by the Wonham filter when it is used for the estimation of the (finite set-valued) jump-Markov parameters of a random parameter linear stochastic system and further give bounds on certain functions of these estimates. We then consider a certainty equivalence adaptive linear-quadratic Gaussian feedback control law using the estimates generated by the nonlinear filter and demonstrate the global existence of solutions to the resulting closed-loop system. A stochastic Lyapunov analysis establishes that the certainty equivalence law stabilizes the Markov jump parameter linear system in the mean square average sense. The conditions for this result are that certain products of (i) the parameter process jump rate and (ii) the solution of the control Riccati equation and its second derivatives should be less than certain given bounds. An example is given where the controlled linear system has state dimension 2. Finally, the stabilizing properties of certainty equivalence laws which depend on (i) the maximum likelihood estimate of the parameter value and (ii) a modified version of this estimate are established under certain conditions.
Pose Estimation by Fusing Noisy Data of Different Dimensions
Authors: Yaacov Hel-Or, Michael Werman
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (1995)

A method for fusing and integrating different 2D and 3D measurements for pose estimation is proposed. The 2D measured data is viewed as 3D data with infinite uncertainty in particular directions. The method is implemented using Kalman filtering. It is robust and easily parallelizable.