ppxscal/embedding_network huggingface dataset:
Evaluating variable resolution displays with visual search: task performance and eye movements
Authors: Derrick Parkhurst, Eugenio Culurciello, Ernst Niebur
Venue: Proceedings of the 2000 symposium on Eye tracking research & applications (2000)

Gaze-contingent variable resolution display techniques allocate computational resources for image generation preferentially to the area around the center of gaze where visual sensitivity to detail is the greatest. Although these techniques are computationally efficient, their behavioral consequences with realistic tasks and materials are not well understood. The behavior of human observers performing visual search of natural scenes using gaze-contingent variable resolution displays is examined. A two-region display was used where a high-resolution region was centered on the instantaneous center of gaze, and the surrounding region was presented in a lower resolution. The radius of the central high-resolution region was varied from 1 to 15 degrees while the total amount of computational resources required to generate the visual display was kept constant. Measures of reaction time, accuracy, and fixation duration suggest that task performance is comparable to that seen for uniform resolution displays when the central region size is approximately 5 degrees.
Incremental Design of Scalable Interconnection Networks Using Basic Building Blocks
Authors: Mingyao Yang, Lionel M. Ni
Venue: IEEE Transactions on Parallel and Distributed Systems (2000)

In this paper, we present an incremental design of scalable interconnection networks in multicomputer systems using basic building blocks. Both network topologies and routing algorithms are considered. We use wormhole-routed small-scale 2D meshes as basic building blocks. The minimum requirement to expand these networks is a single building block. This implies that the network does not have to maintain the regular 2D mesh topology. Some new topologies are introduced: incomplete meshes based on those adaptive routing algorithms designed from the turn model and extended incomplete meshes based on XY routing. We show that the original routing algorithm can be adopted to send a message between any source and destination without using store-and-forward and causing deadlock. The way that the network is constructed incrementally requires no or a very small amount of rewiring and keeps high bisection density and short diameter of the network. The design methods can be used to economically and incrementally build expandable and scalable parallel computers.
The intrinsically exponential complexity of the circularity problem for attribute grammars
Authors: Mehdi Jazayeri, William F. Ogden, William C. Rounds
Venue: Communications of the ACM (1975)

Attribute grammars are an extension of context-free grammars devised by Knuth as a mechanism for including the semantics of a context-free language with the syntax of the language. The circularity problem for a grammar is to determine whether the semantics for all possible sentences (programs) in fact will be well defined. It is proved that this problem is, in general, computationally intractable. Specifically, it is shown that any deterministic algorithm which solves the problem must for infinitely many cases use an exponential amount of time. An improved version of Knuth's circularity testing algorithm is also given, which actually solves the problem within exponential time.
On programming the numerical solution of polynomial equations
Authors: Kenneth W. Ellenberger
Venue: Communications of the ACM (1960)

Numerical techniques are presented for computing the roots of polynomial equations. By applying the recommended scaling and inversion rules, the basic Bistrow and Newton-Raphson iterative techniques can be applied with great reliability. Both a high degree of accuracy and rapid convergence are realized. Numerical examples are shown to illustrate the pitfalls and to show how these are circumvented by application of the recomended procedures.
A knowledge-based system for hardware-software partitioning
Authors: M. L. López
Venue: Proceedings of the conference on Design, automation and test in Europe (1998)

This paper presents SHAPES, a tool for hardware- software partitioning. It is based on two main paradigms: the implementation of the partitioning tool by means of an expert system, and the use of fuzzy logic to model the parameters involved in the process. A Formal Description of VHDL-AMS Analogue Systems83590916abs.htm Tom KazmierskiUniversity of SouthamptonA formal definition of the general VHDL-AMS analogue system has been proposed to relate the way in which the language affects the specification of a non-linear discontinuous analogue system. It has been suggested to model the break set as a separate system in order to facilitate the interaction between the analogue equation set and the digital abstract machine. The significance of the proposed model is that it may be used in semantic validation of VHDL-AMS description and may also facilitate mixed-signal equation formulation for an underlying VHDL-AMS simulator.
Technology mapping for SOI domino logic incorporating solutions for the parasitic bipolar effect
Authors: Srirang K. Karandikar, S. Sapatnekar
Venue: Proceedings of the 38th annual Design Automation Conference (2001)

We present a technology mapping algorithm for implementing a random logic gate network in domino logic. The target technology of implementation is Silicon on Insulator (SOI). SOI devices exhibit an effect known as Parasitic Bipolar Effect (PBE), which can lead to incorrect logic values in the circuit. Our algorithm solves the technology mapping problem by permitting several transformations during the mapping process in order to avoid the PBE, such as transistor reordering, altering the way transistors are organized into gates, and adding pmos discharge transistors. We minimize the total cost of implementation, which includes the discharge transistors required for correct functioning. Our algorithm generates solutions that reduce the number of discharge transistors needed by 44.23%, and reduces the size of the final solution by 11.66% on average.
A multiple-precision division algorithm
Authors: Charles J. Mifsud
Venue: Communications of the ACM (1970)

A generalized division algorithm for use with positive integral operands is presented. Depending upon the algebraic relationship of the first two ciphers of the divisor, one or at most two adjustments to the original divisor and dividend must be performed before the division operation can be initiated. The uniqueness of this method will cause each trial cipher in the quotient to be either equal to or one greater than its final replacement.
XFVHDL: a tool for the synthesis of fuzzy logic controllers
Authors: E. Lago, C. J. Jiménez, D. R. López, S. Sánchez-Solano, A. Barriga
Venue: Proceedings of the conference on Design, automation and test in Europe (1998)

A tool for the synthesis of fuzzy controllers is presented in this paper. This tool takes as input the behavioral specification of a controller and generates its VHDL description according to a target architecture. The VHDL code can be synthesized by means of two implementation methodologies, ASIC and FPGA. The main advantages of using this approach are rapid prototyping, and the use of well-known commercial design environments like Synopsys, Mentor Graphics, or Cadence.
Experimental evaluation of forward error correction on multicast audio streams in wireless LANs
Authors: Philip K. McKinley, Suraj Gaurav
Venue: Proceedings of the eighth ACM international conference on Multimedia (2000)

This paper describes an experimental study of a proxy service to enhance interactive multicast audio streams when transmitted across wireless local area networks. The architecture of the proxy is presented, followed by results of a performance study conducted on a mobile computing testbed. The main contribution of the paper is to evaluate the effectiveness of forward error correcting codes on improving the quality of audio channels for collaborating mobile users.
Error Estimates on the Approximate Finite Volume Solution of Convection Diffusion Equations with General Boundary Conditions
Authors: Thierry Gallouët, Raphaèle Herbin, Marie Hélène Vignal
Venue: SIAM Journal on Numerical Analysis (2000)

We study here the convergence of a finite volume scheme for a diffusion convection equation on an open bounded set of $\R^\dim$ ($\dim=2$ or $3$) for which we consider Dirichlet, Neumann, or Robin boundary conditions. We consider unstructured meshes which include Voronoi or triangular meshes; we use for the diffusion term an "s points" (where s is the number of sides of each cell) finite volume scheme and for the convection term an upstream finite volume scheme. Assuming the exact solution at least in H2 we prove error estimates in a discrete $H^1_0$ norm of order the size of the mesh. Discrete Poincaré inequalities then allow one to prove error estimates in the L2 norm.
One dimension models in the partitioning and placement problems (abstract only)
Authors: Roman Melnyk
Venue: Proceedings of the symposium on Contemporary computing in Ukraine (2000)

The approach for the model partitioning and packaging on the base of the graph linear placement and assignment algorithms is considered. The properties of the constructive and iteration algorithms based on the optimal reduction tree method are described.
Wavelet and Fourier Methods for Solving the Sideways Heat Equation
Authors: Lars Eldén, Fredrik Berntsson, Teresa Reginska
Venue: SIAM Journal on Scientific Computing (1999)

We consider an inverse heat conduction problem, the sideways heat equation, which is a model of a problem, where one wants to determine the temperature on both sides of a thick wall, but where one side is inaccessible to measurements. Mathematically it is formulated as a Cauchy problem for the heat equation in a quarter plane, with data given along the line x=1, where the solution is wanted for $0 \leq x The problem is ill-posed, in the sense that the solution (if it exists) does not depend continuously on the data. We consider stabilizations based on replacing the time derivative in the heat equation by wavelet-based approximations or a Fourier-based approximation. The resulting problem is an initial value problem for an ordinary differential equation, which can be solved by standard numerical methods, e.g., a Runge--Kutta method.We discuss the numerical implementation of Fourier and wavelet methods for solving the sideways heat equation. Theory predicts that the Fourier method and a method based on Meyer wavelets will give equally good results. Our numerical experiments indicate that also a method based on Daubechies wavelets gives comparable accuracy. As test problems we take model equations with constant and variable coefficients. We also solve a problem from an industrial application with actual measured data.
An improved illumination model for shaded display
Authors: Turner Whitted
Venue: Communications of the ACM (1980)

To accurately render a two-dimensional image of a three-dimensional scene, global illumination information that affects the intensity of each pixel of the image must be known at the time the intensity is calculated. In a simplified form, this information is stored in a tree of &ldquo;rays&rdquo; extending from the viewer to the first surface encountered and from there to other surfaces and to the light sources. A visible surface algorithm creates this tree for each pixel of the display and passes it to the shader. The shader then traverses the tree to determine the intensity of the light received by the viewer. Consideration of all of these factors allows the shader to accurately simulate true reflection, shadows, and refraction, as well as the effects simulated by conventional shaders. Anti-aliasing is included as an integral part of the visibility calculations. Surfaces displayed include curved as well as polygonal surfaces.
COPE (Console Operator Proficiency Examination)
Authors: David Farbman, Richard Ketover
Venue: Communications of the ACM (1960)

Each year electronic computers become more sophisticated, and the programs they must process become more complex. Because of this, dependence of those in computing on the skill and experience of operators is increasing. At the same time, selection and training of qualified operators grows more difficult. To meet the need for a quick, accurate, uniform operator test and training aid, the authors have developed COPE (Console Operator Proficiency Examination), outlined below While this examination is programmed specifically for the IBM 705 Mode II with two Tape Record Coordinators, similar programs could be developed for other computers.
Uncertainty Propagation and the Matching of Junctions as Feature Groupings
Authors: Xinquan Shen, Phil Palmer
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (2000)

The interpretation of the 3D world from image sequences requires the identification and correspondences of key features in the scene. In this paper, we describe a robust algorithm for matching groupings of features related to the objects in the scene. We consider the propagation of uncertainty from the feature detection stage through the grouping stage to provide a measure of uncertainty at the matching stage. We focus upon indoor scenes and match junctions, which are groupings of line segments that meet at a single point. A model of the uncertainty in junction detection is described, and the junction uncertainty under the epipolar constraint is determined. Junction correspondence is achieved through matching of each line segment associated with the junction. A match likelihood is then derived based upon the detection uncertainties and then combined with information on junction topology to create a similarity measure. A robust matching algorithm is proposed and used to match junctions between pairs of images. The presented experimental results on real images show that the matching algorithm produces sufficiently reliable results for applications such as structure from motion.
Object-oriented real-time concurrency
Authors: Peter A. Buhr, Ashif S. Harji, Philipp E. Lim, Jiongxiong Chen
Venue: Proceedings of the 15th ACM SIGPLAN conference on Object-oriented programming, systems, languages, and applications (2000)

The primary goal of a real-time system is predictability. Achieving this goal requires all levels of the system to work in concert to provide fixed worst-case execution-times. Un-fortunately, many real-time systems are overly restrictive, providing only ad-hoc scheduling facilities and basic concurrent functionality. Ad-hoc scheduling makes developing, verifying, and maintaining a real-time system extremely difficult and time consuming. Basic concurrent functionality forces programmers to develop complex concurrent programs without the aid of high-level concurrency features.Encouraging the use of sophisticated real-time theory and methodology, in conjunction with high-level concurrency features, requires flexibility and extensibility. Giving real-time programmers access to the underlying system data-structures makes it possible to interact with the system to incorporate new ideas and fine-tune specific applications. This paper explores this approach by examining its effect on a selection of crucial real-time issues: real-time monitors, timeouts, dynamic-priority scheduling and basic priority inheritance. The approach is implemented in mu;C++.
Designing better online teaching material
Authors: Judy Brown, Jiayun Lu
Venue: ACM SIGCSE Bulletin (2001)

The creation of excellent online teaching material is challenging because it requires that designers are able to apply learning theories and usability principles. In this paper we describe a web-based tutorial we developed to teach database students about SQL-like operators that can be used to access data in data warehouses (very large collections of data used by analysts). This paper describes the processes and methods used to develop the tutorial and the techniques we used to test prototypes of our tutorial. We show how ideas from user-centered design and learning theory can be usefully combined to create a new process for developing online teaching material that meets learning and usability aims.
A Radix-10 BKM Algorithm for Computing Transcendentals on Pocket Computers
Authors: L. Imbert, J. M. Muller, F. Rico
Venue: Journal of VLSI Signal Processing Systems (2000)

We present a radix-10 variant of the BKM algorithm. It is ashift-and-add, CORDIC-like algorithm that allows fast computation of complex exponentials and logarithms. It can easily be used to compute the classical real elementary functions (sin, cos, arctan, ln, exp). This radix-10 version is suitable for implementationin a pocket computer.
On the Internal Representations of Product Units
Authors: Jung-Hua Wang, Yi-Wei Yu, Jia-Horng Tsai
Venue: Neural Processing Letters (2000)

This paper explores internal representation power of product units &lsqb;1&rsqb; that act as the functional nodes in the hidden layer of a multi-layer feedforward network. Interesting properties from using binary input provide an insight into the superior computational power of the product unit. Using binary computation problems of symmetry and parity as illustrative examples, we show that learning arbitrary complex internal representations is more achievable with product units than with traditional summing units.
The optimal approach to recursive programs
Authors: Zohar Manna, Adi Shamir
Venue: Communications of the ACM (1977)

The classical fixedpoint approach toward recursive programs suggests choosing the &ldquo;least defined fixedpoint&rdquo; as the most appropriate solution to a recursive program. A new approach is described which introduces an &ldquo;optimal fixedpoint,&rdquo; which, in contrast to the least defined fixedpoint, embodies the maximal amount of valuable information embedded in the program. The practical implications of this approach are discussed and techniques for proving properties of optimal fixedpoints are given. The presentation is informal, with emphasis on examples.
Algorithm 447: efficient algorithms for graph manipulation
Authors: John Hopcroft, Robert Tarjan
Venue: Communications of the ACM (1973)

Efficient algorithms are presented for partitioning a graph into connected components, biconnected components and simple paths. The algorithm for partitioning of a graph into simple paths of iterative and each iteration produces a new path between two vertices already on paths. (The start vertex can be specified dynamically.) If V is the number of vertices and E is the number of edges, each algorithm requires time and space proportional to max (V, E) when executed on a random access computer.
Knowledge discovery in data warehouses
Authors: Themistoklis Palpanas
Venue: ACM SIGMOD Record (2000)

As the size of data warehouses increase to several hundreds of gigabytes or terabytes, the need for methods and tools that will automate the process of knowledge extraction, or guide the user to subsets of the dataset that are of particular interest, is becoming prominent. In this survey paper we explore the problem of identifying and extracting interesting knowledge from large collections of data residing in data warehouses, by using data mining techniques. Such techniques have the ability to identify patterns and build succinct models to describe the data. These models can also be used to achieve summarization and approximation. We review the associated work in the OLAP, data mining, and approximate query answering literature. We discuss the need for the traditional data mining techniques to adapt, and accommodate the specific characteristics of OLAP systems. We also examine the notion of interestingness of data, as a tool to guide the analysis process. We describe methods that have been proposed in the literature for determining what is interesting to the user and what is not, and how these approaches can be incorporated in the data mining algorithms.
A back-end computer for data base management
Authors: R. H. Canaday, R. D. Harrison, E. L. Ivie, J. L. Ryder, L. A. Wehr
Venue: Communications of the ACM (1974)

It is proposed that the data base management function be placed on a dedicated back-end computer which accepts commands (in a relatively high level language such as the CODASYL Data Base Task Group, April 1971 Report) from a host computer, accesses the data base on secondary storage, and returns results. The advantages of such a configuration are discussed. An experimental implementation, called the eXperimental Data Management System, XDMS, is described and certain conclusions about the back-end approach are drawn from this implementation.
From Washington: The robot revolution: an interview with James Albus
Authors: Rosalie Steier
Venue: Communications of the ACM (1983)

There is growing awareness among U.S. manufacturers that time is running short to reorganize production processes and begin investment programs for new technology. Sales of accessories&mdash;robots, computer controls, and materials-handling systems&mdash;are expected to climb to $30 billion world-wide by 1996, compared with the 1982 total of $4 billion.* There is also much discussion about the feasibility of Japan's plans for a fifth generation of computers the danger of their outstripping us, and, in general, what the advent of robotics will do to the quality of life. Do you see the pervasive use of robots as a practical reality? The ACM Portal is published by the Association for Computing Machinery. Copyright © 2010 ACM, Inc. Terms of Usage Privacy Policy Code of Ethics Contact Us Useful downloads: Adobe Acrobat QuickTime Windows Media Player Real Player
Progressive approximate aggregate queries with a multi-resolution tree structure
Authors: Iosif Lazaridis, Sharad Mehrotra
Venue: Proceedings of the 2001 ACM SIGMOD international conference on Management of data (2001)

Answering aggregate queries like SUM, COUNT, MIN, MAX, AVG in an approximate manner is often desirable when the exact answer is not needed or too costly to compute. We present an algorithm for answering such queries in multi-dimensional databases, using selective traversal of a Multi-Resolution Aggregate (MRA) tree structure storing point data. Our approach provides 100% intervals of confidence on the value of the aggregate and works iteratively, coming up with improving quality answers, until some error requirement is satisfied or time constraint as reached. Using the same technique we can also answer aggregate queries exactly and our experiments indicate that even for exact answering the proposed data structure and algorithm are very fast.