ppxscal/embedding_network huggingface dataset:
A method to derive application-specific embedded processing cores
Authors: Olivier Hébert, Ivan C. Kraljic, Yvon Savaria
Venue: Proceedings of the eighth international workshop on Hardware/software codesign (2000)

The concept of system-on-a-chip is becoming increasingly popular for the integration of complex systems. New types of processor cores are now available that enable the designer to customize their processors for the target applications. These soft cores are not tightly coupled with the target application, and this leads to processing cores sub-optimal for their specific applications. This paper proposes a method to derive application-specific embedded processors from soft processor cores. The derivation process involves an analysis of the resources of the processing core used by the target application. Then a series of optimizations based on the analysis results are performed on an optimizable model of the processor core. We present the tool used to perform the analysis of the resources used by an application, and results from a real-world case. Then, various optimization methods are described.
Discretization on Unstructured Grids For Inhomogeneous, Anisotropic Media. Part II: Discussion And Numerical Results
Authors: I. Aavatsmark, T. Barkve, O. Bø
Venue: SIAM Journal on Scientific Computing (1998)

A companion paper, Part I [SIAM J. Sci. Comput., 19 (1998), pp. 1700--1716], presents discretization methods for control-volume formulations in two space dimensions. Properties of the developed methods are further discussed, including rotational invariance and stability under the influence of anisotropy. Strong anisotropy may have to be handled by use of stretched grid cells. Numerical examples that demonstrate strengths and weaknesses of the methods are presented. The examples focus on inhomogeneity, anisotropy, and rotational invariance.
An Algorithm for Scheduling Jobs in Hypercube Systems
Authors: Oh-Heum Kwon, Kyung-Yong Chwa
Venue: IEEE Transactions on Parallel and Distributed Systems (1998)

In this paper, we consider the problem of nonpreemptively scheduling independent jobs so as to minimize overall finish time on an m-dimensional hypercube system. This problem is NP-hard. We propose a polynomial time approximation algorithm and prove that the absolute performance ratio of the algorithm does not exceed 1.875. This is the first algorithm achieving an absolute performance ratio less than two by a constant.
A simulation-based study of scheduling mechanisms for a dynamic cluster environment
Authors: Yanyong Zhang, Anand Sivasubramaniam, Jose Moreira, Hubertus Franke
Venue: Proceedings of the 14th international conference on Supercomputing (2000)

Scheduling of processes onto processors of a parallel machine has always been an important and challenging area of research. The issue becomes even more crucial and difficult as we gradually progress to the use of off-the-shelf workstations, operating systems, and high bandwidth networks to build cost-effective clusters for demanding applications. Clusters are gaining acceptance not just in scientific applications that need supercomputing power, but also in domains such as databases, web service and multimedia, which place diverse Quality-of-Service (QoS) demands on the underlying system. Further, these applications have diverse characteristics in terms of their computation, communication and I/O requirements, making conventional parallel scheduling solutions, such as space sharing or coscheduling, an unattractive option. At the same time, leaving it to the native operating system of each node to make decisions independently can lead to ineffective use of system resources whenever there is communication. Instead, an emerging class of dynamic coscheduling mechanisms, that attempt to take remedial actions to guide the system towards coscheduled execution without requiring explicit synchronization, offer a lot of promise for cluster scheduling. Using a detailed simulator, this paper evaluates the pros and cons of different dynamic coscheduling alternatives, while comparing their advantages over traditional coscheduling (and not performing any coordinated scheduling at all). The impact of dynamic job arrivals, job characteristics and different system parameters on these alternatives are evaluated in terms of several performance criteria.
Fixing a problem in the Helsinki protocol
Authors: Chris J. Mitchell, Chan Yeob Yeun
Venue: ACM SIGOPS Operating Systems Review (1998)

We consider a recently described attack on a key establishment protocol contained in a draft international standard. Based on an observation as to why the attack is possible, we propose a simple modification to the protocol which avoids the attack.
On the Weakness of an Ordered Set
Authors: John G. Gimbel, Ann N. Trenk
Venue: SIAM Journal on Discrete Mathematics (1998)

In this paper we extend the notion of a ranking of elements in a weak order to a ranking of elements in general ordered sets. The weakness of an ordered set P = (X,\prec) (denoted wk(P)) is the minimum integer k for which there exists an integer-valued function lev: X \to Z satisfying: (i) if x \prec y, then lev(x) lev(y); and (ii) if x || y, then |lev(x) - lev(y)| \le k (where "||" denotes incomparability). A forcing cycle L in P is a sequence of elements L: x=v0, v1, . . ., vm = x of P so that for each i \in {0,1, . . ., m-1} either vi \prec vi+1 or vi || vi+1.Our main result relates these two concepts; we prove wk(P) = maxL \llceil\frac{up(L)}{side(L)}\rrceil$, where up(L) = #{i : vi \prec vi+1}, side(L) = #{i : vi || vi+1} and the maximum is taken over all forcing cycles L in P.We also discuss algorithms for computing wk(P) and prove that wk(P) is a comparability invariant.
Performance analysis of multiclass queueing networks
Authors: Dimitris Bertsimas, David Gamarnik, John N. Tsitsiklis
Venue: ACM SIGMETRICS Performance Evaluation Review (1999)

The subject of this abstract is performance analysis of multiclass queueing networks. The objective is to estimate steady-state queue lengths in queueing networks, assuming a priori that the scheduling policy implemented brings the system to a steady state, namely is stable. We propose a very general methodology based on Lyapunov functions, for the performance analysis of infinite state Markov chains and apply it specifically to multiclass exponential type queueing networks. We use, in particular, linear and piece-wise linear Lyapunov function to establish certain geometric type lower and upper bounds on the tail probabilities and bounds on expectation of the queue lengths. The results proposed in this paper are the first that establish geometric type upper and lower bounds on tail probabilities of queue lengths, for networks of such generality. The previous results on performance analysis can in general achieve only numerical bounds and only on expectation and not the distribution of queue lengths.
Generating Pareto Solutions in a Two-Party Setting: Constraint Proposal Methods
Authors: Harri Ehtamo, Raimo P. Hämäläinen, Pirja Heiskanen, Jeffrey Teich, Markku Verkama, Stanley Zionts
Venue: Management Science (1999)

This paper presents a class of methods, called constraint proposal methods, for generating Pareto-optimal solutions in two-party negotiations. In these methods joint tangents of the decision makers' value functions are searched by adjusting an artificial plane constraint. The problem of generating Pareto-optimal solutions decomposes into ordinary multiple criteria decision-making problems for the individual decision makers and into a coordination problem for an assisting mediator. Depending on the numerical iteration scheme used to solve the coordination problem, different constraint proposal methods are obtained. We analyze and illustrate the behaviour of some iteration schemes by numerical examples using both precise and imprecise answers from decision makers. An example of a method belonging to the class under study is the RAMONA method, that has been previously described from a practical point of view. We present the underlying theory for it by describing it as a constraint proposal method, and include some applications.
Experience in retrofiting a large sequential Ada simulator to two versions of Time Warp
Authors: Ray Smith, Randal Andress, George M. Parsons
Venue: Proceedings of the thirteenth workshop on Parallel and distributed simulation (1999)

The Extended Air Defense Testbed (EADTB), is a comprehensive, high- and mixed-level-of-detail, environment for modeling weapon system entities and interactions. Due to the complexity of the models and large scenario sizes, in its current single-threaded form, EADTB is limited in run-time speed. Our goal is to speed up the simulation without re-architecture or re-implementation of the models which comprise 1.76 million lines of Ada code, and without altering model behavior or compromising repeatability and causality. Our work demonstrates that the use of "optimistic scheduling" techniques and its derivatives, offers the best alternative for object-based systems like EADTB. Specifically we have retrofitted and integrated the same representative pseudo-EADTB prototype with two different object-oriented optimistic scheduling engines (SPEEDES and TEMPO/Thema). We discuss the required architectural and behavioral features of a simulation to allow this retrofit, the issues of C++ to Ada language interfaces, and the employment of the basic services of the optimistic scheduling engines in this environment. Experimental results suggest that order-of-magnitude speed-up is feasible through parallelization, and is scalable to larger experiments simply by adding hardware.
Detection of Defects Using Fault Model Oriented Test Sequences
Authors: M. Renovell, F. Azaïs, Y. Bertrand
Venue: Journal of Electronic Testing: Theory and Applications (1999)

This paper analyzes the possibilities and limitations of defect detection using fault model oriented test sequences. The analysis is conducted through the example of a short defect considering the static voltage test technique. Firstly, the problem of defect excitation and effect propagation is studied. It is shown that the effect can be either a defective effect or a defect-free effect depending on the value of unpredictable parameters. The concept of &lsquo;Analog Detectability Interval&rsquo; (ADI) is used to represent the range of the unpredictable parameters creating a defective effect. It is demonstrated that the ADIs are pattern dependent. New concepts (&lsquo;Global ADI&rsquo;, &lsquo;Covered ADI&rsquo;) are then proposed to optimize the defect detection taking into account the unpredictable parameters. Finally, the ability of a fault oriented test sequence to detect defect is discussed. In particular, it is shown that the test sequence generated to target the stuck-at faults can reasonably guarantee short defect detection till a limit given by the Analog Detectability Intervals.
Signed Digit Addition and Related Operations with Threshold Logic
Authors: Sorin Cotofana, Stamatis Vassiliadis
Venue: IEEE Transactions on Computers (2000)

Assuming signed digit number representations, we investigate the implementation of some addition related operations assuming linear threshold networks. We measure the depth and size of the networks in terms of linear threshold gates. We show first that a depth-$2$ network with $O(n)$ size, weight, and fan-in complexities can perform signed digit symmetric functions. Consequently, assuming radix-$2$ signed digit representation, we show that the two operand addition can be performed by a threshold network of depth-$2$ having $O(n)$ size complexity and $O(1)$ weight and fan-in complexities. Furthermore, we show that, assuming radix-$(2n-1)$ signed digit representations, the multioperand addition can be computed by a depth-$2$ network with $O(n^3)$ size with the weight and fan-in complexities being polynomially bounded. Finally, we show that multiplication can be performed by a linear threshold network of depth-$3$ with the size of $O(n^3)$ requiring $O(n^3)$ weights and $O(n^2 \log n)$ fan-in.
On the Sequence of Consecutive Powers of a Matrix in a Boolean Algebra
Authors: Bart De Schutter, Bart De Moor
Venue: SIAM Journal on Matrix Analysis and Applications (1999)

In this paper we consider the sequence of consecutive powers of a matrix in a Boolean algebra. We characterize the ultimate behavior of this sequence, we study the transient part of the sequence, and we derive upper bounds for the length of this transient part. We also indicate how these results can be used in the analysis of Markov chains and in max-plus algebraic system theory for discrete event systems.
Robust Proximity Queries: An Illustration of Degree-Driven Algorithm Design
Authors: Giuseppe Liotta, Franco P. Preparata, Roberto Tamassia
Venue: SIAM Journal on Computing (1999)

In the context of methodologies intended to confer robustness to geometric algorithms, we elaborate on the exact-computation paradigm and formalize the notion of degree of a geometric algorithm as a worst-case quantification of the precision (number of bits) to which arithmetic calculation have to be executed in order to guarantee topological correctness. We also propose a formalism for the expeditious evaluation of algorithmic degree. As an application of this paradigm and an illustration of our general approach where algorithm design is driven also by the degree, we consider the important classical problem of proximity queries in two and three dimensions and develop a new technique for the efficient and robust execution of such queries based on an implicit representation of Voronoi diagrams. Our new technique offers both low degree and fast query time and for 2D queries is optimal with respect to both cost measures of the paradigm, asymptotic number of operations, and arithmetic degree.
A Parallel Algorithm for the Reduction to Tridiagonal Form for Eigendecomposition
Authors: Markus Hegland, Margaret Kahn, Michael Osborne
Venue: SIAM Journal on Scientific Computing (1999)

One-sided orthogonal transformations which orthogonalize columns of a matrix are related to methods for finding singular values. They have the advantages of lending themselves to parallel and vector implementations and simplifying access to the data by not requiring access to both rows and columns. They can be used to find eigenvalues when the matrix is given in factored form. Here, a finite sequence of transformations leading to a partial orthogonalization of the columns is described. This permits a tridiagonal matrix whose eigenvalues are the squared singular values to be derived. The implementation on the Fujitsu VPP series is discussed and some timing results are presented.
Moving mainframe VM users to a distributed UNIX system (KFUPM VM rightsizing experience)
Authors: M. A. Abul-Hamayel, N. S. El-Halmoushi
Venue: International Journal of Network Management (1997)

Migration from one platform to another is a mammoth task. This article describes the experiences of King Fahd University of Petroleum and Minerals in moving from VM&ndash;CMS to UNIX, detailing the reasons for making this change, the problems encountered and drawing practical conclusions that would facilitate such a process. &copy; 1997 John Wiley & Sons, Ltd.
Statistical Performance of a TFD based Detection Scheme
Authors: Owen P. Kenny, Langford B. White
Venue: Multidimensional Systems and Signal Processing (1998)

This paper proposes a robust signal detection procedure based on generalised patterns in time-frequency space. The paper derives a non-linear time domain correlation process which is equivalent to a time-frequency based detection scheme. The performance of this robust detection scheme in the additive white Gaussian noise case is evaluated with the aid of receiver operating curves. Some examples are given which show that the proposed procedure under nominal conditions does not perform as well as standard detection scheme (ie matched filter) but gives better performance when the measured signal deviates from its nominal model.
KOMBIZ97 - virtual lab experiment
Authors: Jerzy Skrzypek, Tadeusz Wilusz
Venue: Proceedings of the 4th annual SIGCSE/SIGCUE ITiCSE conference on Innovation and technology in computer science education (1999)

With the advent of easy available internet and intranet technologies it became possible to redesign concept of building highly valuable managerial skills in real business problems solving using managerial games and make it part of modern, very easy to use and well equipped learning environment. The KOMBIZ97 experiment presented below is growing up every year experiment on setting up such an environment and using throughout more and more courses offered by the Cracow Academy of Economics (CUE).
Table size reduction for data value predictors by exploiting narrow width values
Authors: Toshinori Sato, Itsujiro Arita
Venue: Proceedings of the 14th international conference on Supercomputing (2000)

Recently, the practice of speculation in resolving data dependences has been studied as a means of extracting more instruction level parallelism (ILP). An outcome of an instruction is predicted by value predictors. The instruction and its dependent instructions can be executed simultaneously, thereby exploiting ILP aggressively. One of the serious hurdles for realizing data speculation is huge hardware budget of the predictors. In this paper, we propose a technique reducing the budget by exploiting narrow width values. The hardware budget of value predictors is reduced by up to 45.1%. Simulation results show that the technique, called 2-mode scheme, maintains processor performance with slight decrease of the value prediction accuracy.
Optimism: not just for event execution anymore
Authors: Christoper H. Young, Radharamanan Radhakrishnan, Philip A. Wilsey
Venue: Proceedings of the thirteenth workshop on Parallel and distributed simulation (1999)

Optimism is a technique used by the Time Warp paradigm to make decisions about event execution under uncertainty. While the benefits of throttling the optimism of Time Warp has been studied, the benefits of extending optimism to operations besides event execution is presented in this paper. Specifically, we discuss how optimism can be mapped to fossil collection which has traditionally been assumed to be a non-recoverable operation that must be performed under global control. Optimistic Fossil Collection (OFC) is a technique for fossil collection that does not require global control. However, as states are fossil collected optimistically, a recovery mechanism is required to recover from errors. Performance results show that Time Warp using OFC can improve the performance of simulations on a network of workstations. Another benefit of OFC is that the simulation checkpoints provide for fault tolerance in more than just fossil collection.
Gaussian Spectral Rules for the Three-Point Second Differences: I. A Two-Point Positive Definite Problem in a Semi-Infinite Domain
Authors: Vladimir Druskin, Leonid Knizhnerman
Venue: SIAM Journal on Numerical Analysis (1999)

We suggest an approach to grid optimization for a second order finite-difference scheme for elliptic equations. A model problem corresponding to the three-point finite-difference semidiscretization of the Laplace equation on a semi-infinite strip is considered. We relate the approximate boundary Neumann-to-Dirichlet map to a rational function and calculate steps of our finite-difference grid using the Pad&eacute;--Chebyshev approximation of the inverse square root. It increases the convergence order of the Neumann-to-Dirichlet map from second to exponential without increasing the stencil of the finite-difference scheme and losing stability.
A Similarity Approach to the Numerical Solution of Free Boundary Problems
Authors: Riccardo Fazio
Venue: SIAM Review (1998)

The aim of this work is to point out that within a similarity approach some classes of free boundary value problems governed by ordinary differential equations can be transformed to initial value problems. The interest in the numerical solution of free boundary problems arises because these are always nonlinear problems. Furthermore we show that free boundary problems arise also via a similarity analysis of moving boundary hyperbolic problems and they can be obtained as approximations of boundary value problems defined on infinite intervals. Most of the theoretical content of this survey is original: it generalizes and unifies results already available in literature. As far as applications of the proposed approach are concerned, three problems of interest are considered and numerical results for each of them are reported.
A Comparative Study of Synthesis Methods for Discrete Event Controllers
Authors: L. E. Pinzon, H.-M. Hanisch, M. A. Jafari, T. Boucher
Venue: Formal Methods in System Design (1999)

The purpose of this paper is to illustrate and compare some of the existing synthesis methods for discrete event controllers. We summarize four of the well-known methodologies in the context of plant model, specification model, and controller synthesis procedure. Then, by applying the models to two working examples, we explore and compare the descriptive power of the methods and their capabilities for handling various types of specifications.
Optimization with Variable Sets of Constraints and anApplication to Truss Design
Authors: Wolfgang Achtziger
Venue: Computational Optimization and Applications (2000)

We discuss the minimization of a continuous function on a subset of R^n subject to a finite set of continuous constraints. At each point, a given set-valued map determines the subset of constraints considered at this point. Such problems arise e.g. in the design of engineering structures.After a brief discussion on the existence of solutions, the numerical treatment of the problem is considered. It is briefly motivated why standard approaches generally fail. A method is proposed approximating the original problem by a standard one depending on a parameter. It is proved that by choosing this parameter large enough, each solution to the approximating problem is a solution to the original one. In many applications, an upper bound for this parameter can be computed, thus yielding the equivalence of the original problem to a standard optimization problem.The proposed method is applied to the problem of optimally designing a loaded truss subject to local buckling conditions. To our knowledge this problem has not been solved before. A numerical example of reasonable size shows the proposed methodology to work well.
The computational complexity of knot and link problems
Authors: Joel Hass, Jeffrey C. Lagarias, Nicholas Pippenger
Venue: Journal of the ACM (JACM) (1999)

We consider the problem of deciding whether a polygonal knot in 3-dimensional Euclidean space is unknotted, ie., capable of being continuously deformed without self-intersection so that it lies in a plane. We show that this problem, UNKNOTTING PROBLEM is in NP. We also consider the problem, SPLITTING PROBLEM of determining whether two or more such polygons can be split, or continuously deformed without self-intersection so that they occupy both sides of a plane without intersecting it. We show that it also is in NP. Finally, we show that the problem of determining the genus of a polygonal knot (a generalization of the problem of determining whether it is unknotted) is in PSPACE. We also give exponential worst-case running time bounds for deterministic algorithms to solve each of these problems. These algorithms are based on the use of normal surfaces and decision procedures due to W. Haken, with recent extensions by W. Jaco and J. L. Tollefson.