ppxscal/embedding_network huggingface dataset:
A Shared 4-D Workspace
Authors: Mir Ko, a, Peter Cahoon
Venue:  (1995)

A Shared four-dimensional workspace is a shared animation of three-dimensional databases. Since shared animated workspaces are important to many different types of users, a pilot project was undertaken to implement a shared, time varying workspace. This software permitted the give and take of control by users running the same application across an ATM fiber link running at 100 mbits/sec. The project was divided into two parts. In the first phase, animation of three-dimensional databases in stereo was implemented. In the second phase, sharing of the animation across the ATM network was added. This paper dicusses the interfaces to the program and presents outlines of implementations of the features in each of the project''s two phases.
Edge-Packing in Planar Graphs
Authors: Lenwood S. Heath, John P Vergara
Venue:  (1995)

Maximum G Edge-Packing (EPack-sub G) is the problem of finding the maximum number of edge-disjoint isomorphic copies of a fixed guest graph G in a host graph H. This paper investigates the computational complexity of edge-packing for planar guests and planar hosts. Edge-packing is solvable in polynomial time when both G and H are either a 3-cycle or a k-star (graphs isomorphic to K(sub 1,k). Edge-packing is NP-complete when H is planar and G is either a cycle or a tree with greater than or equal to 3 edges. A strategy for developing polynomial-time approximation algorithms for planar hosts is exemplified by a linear-time approximation algorithm that finds a k-star edge-packing of size at least 1/2 optimal.
Implementing Prolog-Run WWW Sites
Authors: Wamberto Vasconcelos, Rolf Schwitter, Diego Moll, Jo Cavalcanti
Venue:  (2000)

We describe a modular and customisable architecture for a WWW server run by Prolog programs and show how each of its components can be implemented. Our proposal employs standard Prolog-CGI technology but to improve efficiency we also use client-server modules to perform the actual services of the WWW site.
Increasing Memory Bandwidth for Vector Computations
Authors: Sally A. McKee, Steven A. Moyer, Wm Wulf, Charles Y. Hitchcock
Venue:  (1993)

Memory bandwidth is rapidly becoming the performance bottleneck in the application of high performance micro- processors to vector-like algorithms, including the "Grand Challenge" scientific problems. Caching is not the sole solution for these applications due to the poor temporal and spatial locality of their data accesses. Moreover, the nature of memories themselves has changed. Achieving greater bandwidth requires exploiting the characteristics of memory components "on the other side of the cache" - they should not be treated as uniform access-time RAM. This paper describes the use of hardware-assisted access ordering, a technique that combines compile-time detection of memory access patterns with a memory subsystem that decouples the order of requests generated by the processor from that issued to the memory system. This decoupling permits the requests to be issued in an order that optimizes use of the memory system. Our simulations show significant speedup on important scientific ker- nels.
Self-Routing Superconcentrators
Authors: Nicholas Pippenger
Venue:  (1993)

Superconcentrators are switching systems that solve the generic problem of interconnecting clients and servers during sessions, in situations where either the clients or the servers are interchangable (so that it does not matter which client is connected to which server). Previous constructions of superconcentrators have required an external agent to find the interconnections appropriate in each instance. We remedy this shortcoming by constructing superconcentrators that are ``self-routing'''', in the sense that they compute for themselves the required interconnections. Specifically, we show how to construct, for each n, a system S_n with the following properties. (1) The system S_n has n inputs, n outputs, and O(n) components, each of which is of one of a fixed finite number of finite automata, and is connected to a fixed finite number of other components through cables, each of which carries signals from a fixed finite alphabet. (2) When some of the inputs, and an equal number of outputs, are ``marked'''' (by the presentation of a certain signal), then after O(log n) steps (a time proportional to the ``diameter'''' of the network) the system will establish a set of disjoint paths from the marked inputs to the marked outputs.
Application of evolutionary computation to protein folding
Authors: Steffen Schulze-Kremer
Venue: Advances in evolutionary computing: theory and applications (2003)

This chapter demonstrates the application of genetic algorithms to the ab initio protein folding problem. In particular, solutions to the representation issue of protein tertiary structure, of domain-specific genetic operators and a vector fitness function for fold evaluation are presented. Finally, limitations of this approach are discussed.
Sparse Approximate Inverses in Preconditioning Distributed Linear Systems
Authors: Sosonkina Maria
Venue:  (1997)

Using a direct approximation of sparse matrix inverse in preconditioning is viewed as a good alternative to the preconditioning techniques that require a matrix factorization. A sparse approximate inverse is easy to compute and apply, and it is suitable for parallel implementations. For distributed linear systems of varying difficulty, approximate block LU preconditioning using sparse approximate inverse techniques and an incomplete LU factorization used in Block-Jacobi preconditioning are compared.
Analytic Proof Systems for Classical and Modal Logics of Restricted Quantification
Authors: Ian P. Gent
Venue:  (1993)

This thesis is a study of the relationship between proof systems for propositional logic and for logics of restricted quantification incorporating restriction theories. Such logics are suitable for the study of special purpose reasoning as part of a larger system, an important research topic in automated reasoning. Also, modal and sorted logics can be expressed in this way. Thus, results on restricted quantification apply to a wide range of useful logics. D''Agostino''s "expansion systems" are used to generalise results to apply to a variety of tableau-like propositional proof systems.
Analysis of Ultrasound Images of the Prostate Gland: Geometric Transformations and Noise Reduction
Authors: Sonny C.K. Tham
Venue:  (1997)

Ultrasound, as a low cost, non-intrusive, non-toxic and portable tomographic imaging technology has found widespread use in medicine. It is used in diagnosis, treatment and monitoring of various diseases. Prostate disease is a common and serious medical condition in older male humans. One major use of ultrasound is the imaging of the prostate gland. Unfortunately, images produced using pulse-echo ultrasound imaging are subject to high levels of noise and this noise is difficult to characterise mathematically. The prostate gland is examined using ultrasound scans from a transrectal ultrasound probe, shaped like a cylindrical rod, which is inserted into the rectum. The actual transducer is mounted on the end of the probe and produces a polar-type circular scan about the axis of the probe. This kind of scan produces images in the shape of a partial disk that are oriented normal to the axis of the probe. The images that are reconstructed by most ultrasound imaging machines are stretched about the centre of rotation of the transducer and this stretching increases the amount of noise in the image and alters the characteristics of the original noise. This dissertation describes the application of a specialised geometric transformation to B-mode ultrasound images of the prostate gland in an attempt to eliminate the polar stretching phenomenon that is present in ultrasound images produced from transrectal scans of the prostate gland. This transformation will provide a basis for subsequent processing of the images using other techniques. The transformation will change the images into a form where the noise is returned to its original characteristics and will hence improve the performance of image processing algorithms that assume a consistent noise characteristics over the whole image. Two simple image processing algorithms, a median filter mask based despeckling algorithm and a image sharpening algorithm were applied to the transformed images. The development of an inverse transformation is also documented and the inverse transform was applied to images that had been transformed and then processed using the despeckling and sharpening algorithms. This allowed the evaluation of the transformation''s effectiveness in improving the performance of these image processing techniques as compared to the direct application of the two algorithms to the original untransformed images.
Optimal Trajectory Planning for a Space Robot Docking with a MovingTarget via Homotopy Algorithms
Authors: Y. Chen, Layne T. Watson
Venue:  (1993)

The mathematical formulation of optimal trajectory planning for a space robot docking with a moving target is derived. The calculus of variations is applied to the problem so that the optimal robot trajectory can be obtained directlt from the target information without first planning the trajectory of the end-effector. The nonlinear two-point boundary value problem resulting from the problem formulation is solved numerically by a globally convergent homotopy algorithm. The algorithm guarantees convergence to a solution for an arbitrarily chosen initial guess. Numerical simulation for three examples demonstrates the approach.
Notes on the Design of a Barrel Shifter for the Warwick Pipelined CORDIC Processor
Authors: Paul Chown
Venue:  (1990)

This document discusses the design decisions made during the design of the barrel shifters used in the floating point adjustment circuitry of the Warwick pipelined CORDIC processor. The barrel shifter is required for both the input (mantissa alignment) and output (post normalistion) parts of the floating data path, although it also has applications in other areas such as a bit field extraction and multiplication/division. A brief survey of the available techniques will be given, followed by a discussion of the design process for the Barrel shifters in our implementatioof the CORDIC algorithm
A Task and Resource Scheduling System for Automated Planning
Authors: David P. Miller
Venue:  (1987)

Planning is done at both the strategic and tactical levels. This paper classifies some previous planning techniques into these different levels, and details some of their problems. A planning technique known as heuristic task scheduling is then presented along with a planner architecture that integrates task-scheduling with more traditional techniques to form a system that bridges the strategic/tactical deviation.
A Bijection for the Convolution of Central Binomial Coefficients
Authors: Omer Egecioglu
Venue:  (1999)

Let $A_n = {2n \choose n }$ for $ n \geq 0$ denote the the $n$-th element in the axis of symmetry of the Pascal triangle. The generating function for $A_n$ is $ (1-4t)^{-1/2}$, from which it follows that $ A_0 A_n + A_1 A_{n-1} + \cdots + A_n A_0 = 4^n $. This note describes a bijective proof of this identity based on lattice paths.
The Performance of Replicated Databases using Atomic Broadcast Group Communication
Authors: JoAnne Holliday, Divyakant Agrawal, Amr El Abbadi
Venue:  (1999)

Database replication with update-anywhere capability while maintaining global synchronization and isolation has long been thought impractical. Protocols have been proposed for distributed replicated databases that take advantage of atomic broadcast systems to simplify message passing and conflict resolution in hopes of making replication efficient. This paper presents performance measurements on a simulation of a distributed replicated database using those protocols. The results show that with the proper group broadcast mechanism, replication with update-anywhere capability is indeed practical.
Development of an AEGIS Maintenance Methodology Task 2: Models of theAEGIS Maintenance Process
Authors: Benjamin J. Keller, Richard E. Nance, James D. Arthur
Venue:  (1990)

Covering the Task 2 effort in the development of an AEGIS software maintenance methodology, the derivation of requirements from maintenance principles is summarized. Three models of the maintenance process provide the basis for identifying points of application. The mid-level (aggregate) model is the major focus of the methodology definition. Recommendations address the potential uses of different modeling perspectives, better balance between products and process assessment, use of metrics, and the selection of maintenance tools.
Cartesian Products of Graphs as Spanning Subgraphs of de Bruijn Graphs
Authors: Thomas Andreae, Michael Nolle, Gerald Schreiber
Venue:  (1994)

For Cartesian products G=G_1 times dots times G_m (m geq 2) of nontrivial connected graphs G_i and the n-dimensional base B de Bruijn graph D=D_B(n), we investigate whether or not there exists a spanning subgraph of D which is isomorphic to G. We show that G is never a spanning subgraph of D when n is greater than three or when n equals three and m is greater than two. For n=3 and m=2, we can show for wide classes of graphs that G cannot be a spanning subgraph of D. In particular, these non-existence results imply that D_B(n) never contains a torus (i.e., the Cartesian product of mge2 cycles) as a spanning subgraph when n is greater than two. For n=2 the situation is quite different: we present a sufficient condition for a Cartesian product G to be a spanning subgraph of D=D_B(2). As one of the corollaries we obtain that a torus G=G_1 timesdotstimes G_m is a spanning subgraph of D=D_B(2) provided that |G|=|D| and that the G_i are even cycles of length ge 4. In addition we apply our results to obtain embeddings of relatively small dilation of popular processor networks (as tori, meshes and hypercubes) into de Bruijn graphs of fixed small base.
On Gapping Grammars
Authors: Harvey Abramson, Veronica Dahl
Venue:  (1984)

A Gapping Grammar (GG) has rewriting rules of the form: \[\alpha_{1}, {\em gap}(x_{1}), \alpha_{2}, {\em gap}(x_{2}), \ldots, \alpha_{n-1}, {\em gap}(x_{n-1}), \alpha_{n} \rightarrow \beta\] \[\alpha_{i} \epsilon V_{N} \bigcup V_{T}\] \{ {\em gap}(x_{1}),{\em gap}(x_{2}), \ldots,{\em gap}(x_{n-1}) \}\] \[x_{i} \epsilon V_{T}^{*}\] \[\beta \epsilon V_{N}^{*} \bigcup V_{T}^{*} \bigcup G^{*}\] where $V_{T}$ and $V_{N}$ are the terminal and non-terminal vocabularies of the Gapping Grammar. Intuitively, a GG rule allows one to deal with unspecified strings of terminal symbols called {\em gaps}, represented by $x_{1}, x_{2}, \ldots, x_{n-1}$, in a given context of specified terminals and non-terminals, represented by $\alpha_{1}, \alpha_{2}, \ldots, \alpha_{n}$ and then to distribute them in the right hand side $\beta$ in any order. GG''s are a generalization of Fernando Pereira''s {\em Extrapontion Grammars} where rules have the form (using our notation ): \begin{eqnarray*} \alpha_{1},{\em gap}(x_{1}), \alpha_{2}, {\em gap}(x_{2}), \ldots, {\em gap}(x_{n-1}), \alpha_{n} \rightarrow \\ \beta, {\em gap}(x_{1}), {\em gap}(x_{2}), \ldots, {\em gap}(x_{n-1}) \end{eqnarray*} i.e., gaps are rewritten in their sequential order in the rightmost positions of the rewriting rule. In this paper we motivate GG''s by presenting grammatical examples where XGs are not adequate and we describe and discuss alternative implementations of GGs in logic.
First Experiences with TMM
Authors: Kevin A. Mayo
Venue:  (1993)

The Task Mapping Model (TMM) is a human-computer interaction technique that supports situational analyses to derive new design requirements from formative evaluation findings. While the TMM methodologies and formalisms are currently being developed and validated, this paper reports some informal first experiences and findings. Two developers who are presently working on independent non-trivial interfaces were asked to use TMM and comment on it. The developers found benefit in TM analyses, albeit in different ways, and their views were captured with an informal subjective post-analysis survey and reported here.
SIMULATING NETWORK TRAFFIC IN AN ASSOCIATIVE PROCESSING ENVIRONMENT (M.S. Thesis)
Authors: Claude S. Noshpitz
Venue:  (1993)

This thesis considers issues related to the design of a distributed computing system optimized for research in the area of artificial intelligence applications. We introduce the Associative Processing Environment, a computing model explicitly designed to provide support at the machine level for systems that learn. Issues relating to the implementation of a multicomputer based on this model are discussed with a focus on the development of an effective processor interconnection network. We describe APES, a software tool for the simulation of message traffic in such a system, and present a series of experiments testing the behavior of a parallelized AI application on several topologies. We conclude that the behavior of the application is such that an assumption of uniformly distributed random traffic fails to capture essential aspects of the program''s communication activity. 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
Geometric and Computational Aspects of Manufacturing Processes
Authors: Bose Prosenjit K.
Venue:  (1995)

Two of the fundamental questions that arise in the manufacturing industry concerning every type of manufacturing process are: 1) Given an object, can it be built using a particular process? 2) Given that an object can be built using a particular process, what is the best way to construct the object? The latter question gives rise to many different problems depending on how best is qualified. We address these problems for two complimentary categories of manufacturing processes: rapid prototyping systems and casting processes. The method we use to address these problems is to first define a geometric model of the process in question and then answer the questions on that model. In the category of rapid prototyping systems, we concentrate on stereolithography, which is emerging as one of the most popular rapid prototyping systems. We model stereolithography geometrically and then study the class of objects that admit a construction in this model. For the objects that admit a construction, we find the orientations that allow a construction of the object. In the category of casting processes, we concentrate on gravity casting and injection molding. We first model the process and its components geometrically. We then characterize and recognize the objects that can be formed using a re-usable two-part cast. Given that a cast of an object can be formed, we determine a suitable location for the pin gate, the point from which liquid is poured or injected into a mold. Finally, we compute an orientation of a mold that ensures a complete fill and minimizes the number of venting holes for molds used in gravity casting processes.
ACCESSING REPLICATED DATA IN A LARGE-SCALE DISTRIBUTED SYSTEM (M.S. Thesis)
Authors: Richard A Golding
Venue:  (1991)

Many distributed applications use replicated data to improve the availability of the data, and to improve access latency by locating copies of the data near to their use. This thesis presents a new family of communication protocols, called *quorum multicasts*, that provide efficient communication services for replicated data. Quorum multicasts are similar to ordinary multicasts, which deliver a message to a set of destinations. The new protocols extend this model by allowing delivery to a subset of the destinations, selected according to distance or expected data currency. These protocols provide well-defined failure semantics, and can distinguish between communication failure and replica failure with high probability. The thesis includes a performance evaluation of three quorum multicast protocols. This required taking several measurements of the Internet to determine distributions for communication latency and failure. The results indicate that the behavior of recent messages is a useful predictor for the performance of the next. A simulation study of quorum multicasts, based on the Internet measurements, shows that these protocols provide low latency and require few messages. A second study that measured a test application running at several sites confirmed these results.
Automatic Counterflow Pipeline Synthesis
Authors: Bruce R. Childers, Jack W. Davidson
Venue:  (1998)

The Counterflow Pipeline (CFP) organization may be a good target for synthesis of application-specific microprocessors because it has a regular and simple structure. This paper describes early work using CFP''s to improve overall application performance by tailoring a CFP to the kernel loop of an application. A CFP is customized for an application using the kernel loop''s data dependency graph to determine processor functionality and interconnection. Our technique builds the design space for a given data dependency graph and explores the space to find the design with the best performance. Preliminary results indicate that speed-up for several small graphs range from 1.3 to 2.0 and that our design space traversal heuristics find designs that are within 10% of optimal.
Efficiently Implementing Pure Prolog or: Not ``YAWAM''''
Authors: Peter Ludemann
Venue:  (1986)

High performance hardware and software implementations of Prolog are now being developed by many people, using the Warren Abstract Machine (or ``WAM'''') [Warr83]. We have designed a somewhat different machine which supports a more powerful language than Prolog, featuring: \begin{itemize} \item efficiency similar to the WAM for sequential programs, \item tail recursion optimization (TRO) [Warr86], \item sound negation, \item pseudo-parallelism (co-routining) with full backtracking, \item dynamic optimization of clause order, \item efficiency {\em if-then-else} (``shallow'''' backtracking), \item simple, regular instruction set designed for easily optimized compilation, \item efficient memory utilization, \item integrated object-oriented virtual memory, \item predicates as first class objects. \end{itemize} Our design gives the programmer more flexibility in designing programs than is provided by standard Prolog, yet it retains the efficiency of more limited designs.
Linda-LAN: A Controlled Parallel Processing Environment
Authors: George E. Cline, James D. Arthur
Venue:  (1992)

An investigation is performed on a controlled parallel processing environment based upon the Linda paradigm, a conceptually simple programming and operational framework. The environment efficiently and effectively manages system resources via a centralized control sub-system. A detailed overview of the environment executing on a local area network is presented along with analysis on its control sub-system. The control sub-system''s execution characteristics of stability and scalability are also substantiated.