ppxscal/embedding_network huggingface dataset:
Synthesis of signal processing structured datapaths for FPGAs supporting RAMs and busses
Authors: Baher Haroun, Behzad Sajjadi
Venue: Proceedings of the 1995 ACM third international symposium on Field-programmable gate arrays (1995)

A novel approach is presented for transforming a given scheduled and bound signal processing algorithm for a multiplexer based datapath to a BUS/RAM based FPGA datapath. A datapath model is introduced that allows maximum flexibility in scheduling bus transfers independent of operation scheduling. A novel integer linear programming (ILP) formulation that optimally selects and assigns data-transfers to busses while scheduling the bus transfers to minimize a linear combination of the number of busses, bus loading in terms of tristate drivers and fanout, registers and register file storage (RAM) locations. We demonstrate that our resulting optimal datapaths compare favorably to others for signal processing synthesis benchmarks such as: single and multiple elliptic filter and fast discrete-cosine-transform (FDCT).
An Efficient Iterative Solution Method for the Chebyshev Collocation of Advection-Dominated Transport Problems
Authors: A. Pinelli, W. Couzy, M. O. Deville, C. Benocci
Venue: SIAM Journal on Scientific Computing (1996)

A new Chebyshev collocation algorithm is proposed for the iterative solution of advection-diffusion problems. The main features of the method lie in the original way in which a finite-difference preconditioner is built and in the fact that the solution is collocated on a set of nodes matching the standard Gauss--Lobatto--Chebyshev set only in the case of pure diffusion problems. The key point of the algorithm is the capability of the preconditioner to represent the high-frequency modes when dealing with advection-dominated problems. The basic idea is developed for a one-dimensional case and is extended to two-dimensional problems. A series of numerical experiments is carried out to demonstrate the efficiency of the algorithm. The proposed algorithm can also be used in the context of the incompressible Navier--Stokes equations.
A survey of current object-oriented databases
Authors: Mansour Zand, Val Collins, Dale Caviness
Venue: ACM SIGMIS Database (1995)

Object-oriented concepts form a good basis for the data models required for next-generation database applications such as CAD/CAE/CASE/CAM systems, knowledge-based systems, multimedia, etc. Many object-oriented databases are available commercially or are being developed by industry or academic research facilities. This paper attempts to compare some of these products using fourteen criteria. The selected criteria are major factors required for the successful design of an object-oriented database system. They are grouped into five different categories. The result of the survey is summarized in a table.
Software engineering process model: a case study
Authors: Gary J. Nutt
Venue: Proceedings of conference on Organizational computing systems (1995)

Recently a faction of software engineering researchers has focused their attention on studying the process by which software is produced, stimulating interest in models to specify, design, and implement software. A significant part of the practicing software industry must produce software that conforms to a documentation standard (military standard 2167A) for software products; it is intended to ensure that delivered software meets the documentation requirements. This paper is a case study of how a government software contractor might use models to define a process for designing and implementing a software product that complies with the documentation requirements. The intent of the paper is to apply business process modeling technology to the software engineering domain, thus exploring strengths and weaknesses of our evolving models of group collaboration. The case study illustrates an alternative way to design, analyze, and track software processes. It also attempts to illustrate how the model might &ldquo;break down&rdquo; as the basis of an enactment model if it were to be used to coordinate the work of a large number of software developers.
Parallel execution for serial simulators
Authors: David Nicol, Philip Heidelberger
Venue: ACM Transactions on Modeling and Computer Simulation (TOMACS) (1996)

This article 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 submodels with an existing sequential simulation modeling tool, using the full expressive power of the tool. A set of modeling language extensions permits automatically sychronized communication between submodels; however, the automation requires that any such communication must take a nonzero amount of simulation time. Within this modeling paradigm, a variety of conservative synchronization protocols can transparently support conservative execution of submodels 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 and on the IBM SP2.
Simulating the effects of work-in-process on customer satisfaction in a manufacturing environment
Authors: Kenneth V. Buxton, Robert Gatland
Venue: Proceedings of the 27th conference on Winter simulation (1995)

Addresses the effects of varying levels of work-in-process (WIP) on product turntime, delivery time and customer satisfaction. By analyzing a static manufacturing process with known demand, a company can determine the optimum level of WIP, meet customer demand and ensure customer satisfaction. Determining the optimum level of WIP through actual changes in the manufacturing process can negatively affect customer satisfaction. Attempting to find the optimum level via a spreadsheet model does not take into account the interdependency of resources. Development of a simulation model allows for off-line analysis without any physical changes to the process and provides better results than a standard spreadsheet model.
Scalability issues in enhancement of the MAGTF tactical warfare simulation system
Authors: Curtis L. Blais
Venue: Proceedings of the 27th conference on Winter simulation (1995)

The Marine Air Ground Task Force (MAGTF) Tactical Warfare Simulation (MTWS) system is a computer-assisted, two-sided warfare gaming system designed to support training of U.S. Marine Corps commanders and their staffs. Primary requirements for the system were written in the early 1980s. Since then, a transition in training from uni-service to joint and coalition warfare scenarios has occurred. Primary use of MTWS will continue to be within the Fleet Marine Force and USMC University settings. However, there are growing demands for the system to participate in joint exercises involving other constructive simulations and diverse virtual simulations. Therefore, the requirement to support exercises from Marine Expeditionary Unit (MEU) through Marine Expeditionary Force (MEF) levels is being extended to cover larger force structures with an order of magnitude increase in the number of game objects. The technical challenge is to significantly enlarge system capacity without sacrificing essential system performance and fidelity. Several issues are being investigated to achieve this expanded capability. The paper describes hardware and software approaches and alternatives relating to architecture and functionality. For each alternative, the current capability is briefly presented, followed by a description and analysis of scalability issues and alternatives.
On Compatible Priors for Bayesian Networks
Authors: Robert G. Cowell
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (1996)

Given a Bayesian network of discrete random variables with a hyper-Dirichlet prior, a method is proposed for assigning Dirichlet priors to the conditional probabilities of structurally different networks. It defines a distance measure between priors which is to be minimized for the assignment process. Intuitively one would expect that if two models' priors are to qualify as being 'close' in some sense, then their posteriors should also be nearby after an observation. However one does not know in advance what will be observed next. Thus we are led to propose an expectation of Kullback-Leibler distances over all possible next observations to define a measure of distance between priors. In conjunction with the additional assumptions of global and local independence of the parameters [15], a number of theorems emerge which are usually taken as reasonable assumptions in the Bayesian network literature. The method is compared to the 'expansion and contraction' algorithm of [14], and is also contrasted with the results obtained in [7] who employ the additional assumption of likelihood equivalence which is not made here. A simple example illustrates the technique.
Complexity of kernel Fun subtype checking
Authors: Giorgio Ghelli
Venue: ACM SIGPLAN Notices (1996)

System kernel Fun is an abstract version of the system Fun defined by Cardelli's and Wegner's seminal paper [CW85], and is strictly related to system F le;. Extensions of these two systems are currently the basis of most proposals for strong type systems for object-oriented languages.We study here the problem of subtype checking for system kernel Fun, presenting the following results. We show that the standard kernel Fun subtype checking algorithm has an exponential complexity, and generates an exponential number of different subproblems. We then present a new subtype checking algorithm which has a polynomial complexity. In the process we study how variable names can be managed by a kernel Fun subtype checker which is not based on the De Bruijn encoding, and we show how to perform kernel Fun subtype checking with a "constraint generating" technique.The algorithm we give is described by a set of type rules, which we prove to be equivalent to the standard one. This new presentation of kernel Fun type system is characterized by a "multiplicative" behaviour, and it may open the way to new presentations for system F le; as well.
An extension of Ukkonen's enhanced dynamic programming ASM algorithm
Authors: Hal Berghel, David Roach
Venue: ACM Transactions on Information Systems (TOIS) (1996)

We describe an improvement on Ukkonen's Enhanced Dynamic Programming (EHD) approximate string-matching algorithm for unit-penalty four-edit comparisons. The new algorithm has an asymptotic complexity similar to that of Ukkonen's but is significantly faster due to a decrease in the number of array cell calculations. A 42% speedup was achieved in an application involving name comparisons. Even greater improvements are possible when comparing longer and more dissimilar strings. Although the speed of the algorithm under consideration is comparable to other fast ASM algorithms, it has greater effectiveness in text-processing applications because it supports all four basic Damerau-type editing operations.
Selecting MIS projects by steering committee
Authors: J. D. McKeen, Tor Guimaraes
Venue: Communications of the ACM (1985)

Steering committees have recently gained vast acceptance in organizations as the mechanism used to select management information systems (MIS) projects. Because of their widespread adoption and their differences from other selection mechanisms with respect to orientation, steering committees were chosen for study. Data from 92 projects selected from 32 organizations were analyzed. As hypothesized, projects selected by steering committees were found to differ significantly from those chosen via other selection mechanisms. The implications of this result for organizations using steering committees to select MIS projects are presented.
A parallel processing approach to transition prediction for laminar flow control system design
Authors: R. W. Ford, D. I. A. Poll
Venue: Scientific Programming (1995)

The performance of transport aircraft can be considerably improved if the process by which the wing boundary layer becomes turbulent can be controlled and extensive areas of laminar flow maintained. In order to design laminar flow control systems, it is necessary to be able to predict the movement of the transition location in response to changes in control variables, e.g., surface suction. At present, the technique which is available to industry requires excessively long computational time - so long that it is not suitable for use in the "design process." Therefore, there is a clear need to produce a system which delivers results in near realtime, i.e., in seconds rather than hours. This article details how parallel computing techniques on a KSR-1 produce these performance improvements.
A Divide-and-Conquer Algorithm for the Bidiagonal SVD
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 singular value decomposition (SVD) of a lower bidiagonal matrix. Previous divide-and-conquer algorithms all suffer from a potential loss of orthogonality among the computed singular vectors unless extended precision arithmetic is used. A generalization that computes the SVD of a lower banded matrix is also presented.
Protected types with entry barriers depending on parameters of the entries: some practical examples
Authors: Pascal Ledru
Venue: ACM SIGAda Ada Letters (1995)

Entry barriers of a protected type have one subtle restriction: they are not allowed to depend on parameters of the entry. This paper reviews how to implement protected types with entry barriers depending on parameters of the entries.
BURS automata generation
Authors: Todd A. Proebsting
Venue: ACM Transactions on Programming Languages and Systems (TOPLAS) (1995)

A simple and efficient algorithm for generating bottom-up rewrite system (BURS) tables is described. A small code-generator generator implementation produces BURS tables efficiently, even for complex instruction set descriptions. The algorithm does not require novel data structures or complicated algorithmic techniques. Previously published methods for on-the-fly elimination of states are generalized and simplified to create a new method, triangle trimming, that is employed in the algorithm. A prototype implementation, burg, generates BURS tables very efficiently.
Efficient building and placing of gating functions
Authors: Peng Tu, David Padua
Venue: Proceedings of the ACM SIGPLAN 1995 conference on Programming language design and implementation (1995)

In this paper, we present an almost-linear time algorithm for constructing Gated Single Assignment (GSA), which is SSA augmented with gating functions at &oslash;-nodes. The gating functions specify the control dependences for each reaching definition at a &oslash;-node. We introduce a new concept of gating path, which is path in the control flow graph from the immediate dominator u of a node v to v, such that every node in the path is dominated by u. Previous algorithms start with &oslash;-function placement, and then traverse the control flow graph to compute the gating functions. By formulating the problem into gating path construction, we are able to identify not only a &oslash;-node, but also a gating path expression which defines a gating function for the &oslash;-node.
Timing Analysis of Ada Tasking Programs
Authors: James C. Corbett
Venue: IEEE Transactions on Software Engineering (1996)

Concurrent real-time software is increasingly used in safety-critical embedded systems. Assuring the quality of such software requires the rigor of formal methods. In order to analyze a program formally, we must first construct a mathematical model of its behavior. In this paper, we consider the problem of constructing such models for concurrent real-time software. In particular, we provide a method for building mathematical models of real-time Ada tasking programs that are accurate enough to verify interesting timing properties, and yet abstract enough to yield a tractable analysis on nontrivial programs. Our approach differs from schedulability analysis in that we do not assume that the software has a highly restricted structure (e.g., a set of periodic tasks). Also, unlike most abstract models of real-time systems, we account for essential properties of real implementations, such as resource constraints and run-time overhead.
Numerical Methods for Nearly Singular Constrained Matrix Sylvester Equations
Authors: Ali R. Ghavimi, Alan J. Laub
Venue: SIAM Journal on Matrix Analysis and Applications (1996)

A recently published result describes a numerical procedure for solving a matrix Sylvester equation that is subject to certain constraints. It is quite possible that this Sylvester equation, or another intermediate one in the solution process, is nearly singular. As a result, certain computed parameters can have unexpectedly large norms and be very inaccurate. This paper incorporates an implicit deflation method for nearly singular matrix Sylvester equations to implement a reliable version of the published algorithm.
A visual interface for a database with version management
Authors: Jay W. Davison, Stanley B. Zdonik
Venue: ACM Transactions on Information Systems (TOIS) (1986)

This paper describes a graphical interface to an experimental database system which incorporates a built-in version control mechanism that maintains a history of the database development and changes. The system is an extension of ISIS [6], Interface for a Semantic Information System, a workstation-based, graphical database programming tool developed at Brown University. ISIS supports a graphical interface to a modified subset of the Semantic Data Model (SDM) [7]. The ISIS extension introduces a transaction mechanism that interacts with the version control facilities. A series of version control support tools have been added to ISIS to provide a notion of history to user-created databases. The user can form new versions of three types of ISIS objects: a class definition object (a type), the set of instances of a class (the content), and an entity. A version-viewing mechanism is provided to allow for the comparison of various object versions. Database operations are grouped together in atomic units to form transactions, which are stored as entities in the database. A sample session demonstrates the capabilities of version and transaction control during the creation and manipulation of database objects.
Local Error Estimates for the Galerkin Method Applied to Strongly Elliptic Integral Equations on Open Curves
Authors: Thanh Tran
Venue: SIAM Journal on Numerical Analysis (1996)

Saranen [Math. Comp., 48 (1987), pp. 485--502] proved local estimates in Sobolev norms for the Galerkin method applied to strongly elliptic equations on smooth closed curves in the plane. We extend his results to the case of open curves. Of particular interest are weakly singular and hypersingular integral equations on a slit. An interesting outcome from our result is that we can judge the orders of convergence of the local errors in some norms that do not exist in the global sense.
Automated load balancing in SPEEDES
Authors: Linda F. Wilson, David M. Nicol
Venue: Proceedings of the 27th conference on Winter simulation (1995)

Parallel discrete event simulation offers the potential for significant speedup over sequential simulation. Unfortunately, high performance is often achieved only after rigorous fine tuning is used to obtain an efficient mapping of tasks to processors. In practice, good performance with minimal effort is often preferable to high performance with excessive effort. We discuss our research in adding automated load balancing to the SPEEDES simulation framework. Using simulation models of queuing networks and the National Airspace System, we demonstrate that using run time measurements, our automated load balancing scheme can achieve better performance than simple allocation methods that do not use run time measurements, particularly when large numbers of processors are used.
Generalization and analysis of the Lisberger-Sejnowski VOR model
Authors: Ning Qian
Venue: Neural Computation (1995)

Lisberger and Sejnowski (1992) recently proposed a computational model for motor learning in the vestibular-ocular reflex (VOR) system. They showed that the steady-state gain of the system can be modified by changing the ratio of the two time constants along the feedforward and the feedback projections to the Purkinje cell unit in their model VOR network. Here we generalize their model by including two additional time constant variables and two synaptic weight variables, which were set to fixed values in their original model. We derive the stability conditions of the generalized system and thoroughly analyze its steady-state and transient behavior. It is found that the generalized system can display a continuum of behavior with the Lisberger-Sejnowski model and a static model proposed by Miles et al. (1980b) as special cases. Moreover, although mathematically the Lisberger-Sejnowski model requires two precise relationships among its parameters, the model is robust against small perturbations from the physiological point of view. Additional considerations on the gain of smooth pursuit eye movement, which is believed to share the positive feedback loop with the VOR network, suggest that the VOR network should operate in the parameter range favoring the behavior studied by Lisberger and Sejnowski. Under this condition, the steady-state gain of the VOR is found to depend on all four time constants in the network. The time constant of the Purkinje cell unit should be relatively small in order to achieve effective VOR learning through the modifications of the other time constants. Our analysis provides a thorough characterization of the system and could thus be useful for guiding further physiological tests of the model.
Control Time For Gravity-Capillary Waves on Water
Authors: Russell M. Reid
Venue: SIAM Journal on Control and Optimization (1995)

This paper considers distributed open-loop control of small-amplitude linear waves on a fluid in which both surface tension and gravity are significant. It formulates the control system as a first-order evolution equation, reducing the null controllability problem to a moment problem involving frequency exponentials. For simple geometries in which eigenvalues can be calculated explicitly, controllability in arbitrary finite time is established, and a relationship between mode frequencies and controller norm is noted.
When an advantage is not an advantage
Authors: Lisa M. Zurk, Barbara Simons Rebecca Parsons, Dawn Cohen
Venue: Communications of the ACM (1995)

Discussion of the merits and shortcomings of affirmative action (AA) has raged at all levels and in many forums and has been the concern of many policymakers, including President Clinton. Notably absent from the discussion is the perception of AA, and the effect of the angry backlash on women and minorities. Recently, the question of whether women enjoy an &ldquo;unfair advantage&rdquo; was posted electronically on Systers, a private organization of over 1,800 professional women in the male-dominated field of computing. The 42 responses contained strong personal stories from women at every level of professional growth who had all dealt with the issues of gender bias and AA at each step of the way.