ppxscal/embedding_network huggingface dataset:
Hoard: A Scalable Memory Allocator for Multithreaded Applications
Authors: Emery Berger, Kathryn McKinley, Robert Blumofe, Paul Wilson
Venue:  (2000)

Parallel, multithreaded programs such as web servers, database managers, news servers, and scientific applications are becoming increasingly prevalent. For these C and C++ applications, the memory allocator is often a bottleneck that severely limits program performance and scalability on multiprocessor systems. Previous allocators suffer from problems that include poor performance and scalability, and heap organizations that introduce false sharing. Worse, many allocators exhibit a "blowup" in memory consumption when confronted with a producer-consumer pattern of object allocation and freeing. This blowup can increase memory consumption by a factor of P (the number of processors) or lead to unbounded memory consumption. Such pathological behavior can cause premature program termination by exhausting all available swap space. This paper introduces Hoard, a fast, highly scalable allocator that avoids false sharing and blowup. Hoard is the first allocator to simultaneously solve the above problems. Hoard combines one global heap and P per-processor heaps with a novel discipline that provably bounds blowup and has near zero synchronization costs in the common case. Our results on eleven programs demonstrate that Hoard yields low average fragmentation and improves overall program performance over the standard Solaris allocator by up to a factor of 60 on 14 processors, and up to a factor of 18 over the next best allocator we tested.
Making Shaders More Physically Plausible
Authors: Robert R. Lewis
Venue:  (1993)

There is a need to develop shaders that not only "look good", but are more physically plausible. From physical and geometric considerations, we review the derivation of a shading equation expressing reflected radiance in terms of incident radiance and the bidirectional reflectance distribution function (BRDF). We then examine the connection between this equation and conventional shaders used in computer graphics. Imposing the additional physical constraints of energy conservation and Helmholtz reciprocity allows us to create variations of the conventional shaders that are more physically plausible. 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
Multicasting in DIS: A unified solution
Authors: Bronis Supinski
Venue:  (1995)

Multicasting, as an alternative to broadcasting, has great potential to improve DIS scalability by reducing the demands on network bandwidth and computational resources. We take an eclectic approach to incorporating multicasting into DIS, blending new ideas based on insights discussed here with the best schemes proposed previously. To our knowledge, no previous work has provided such a unification. The simplicity and completeness of our approach make it more promising than previous ones. In general (and in DIS in particular), the multicast problem should be considered as consisting of two parts: i) definition and use of multicast groups, and ii) efficient implementation of these groups. We describe a method for defining and using multicast groups, present its implementation requirements and show these to be realizable. Further, we provide insights into the configuration of DIS networks in order to obtain the most benefit from multicasting. Finally, we note that management of static objects is inherently related to any multicast solution. The integration of static object management with our multicast solution is made possible by its static nature and use of a regular grid.
Visualizing evolutionary computation
Authors: Trevor D. Collins
Venue: Advances in evolutionary computing: theory and applications (2003)

Visualization is an interdisciplinary area drawing on work done in a variety of areas, such as graphic design, cinematography, typography, animation, and human computer interaction. During the last few years there has been an increasing trend within the evolutionary computation community to apply visualization techniques to facilitate people's understanding and use of evolutionary algorithms. This chapter is intended to provide an introductory review of the existing work done on visualizing evolutionary computation and identify some of the key directions for future research.
Performance Evaluation of an Active Database Management System: 007Meets the BEAST
Authors: A. Geppert, S. Gatziu, K. R. Dittrich
Venue:  (1994)

We present a benchmark for active database management systems. Active functionality that is relevant for performance is identified, and a series of tests is designed that measure the efficiency of the corresponding components. Furthermore, we describe results obtained from running the benchmark for a concrete system.
The Phoenix Recovery System: Rebuilding from the ashes of an Internet catastrophe
Authors: Flavio Junqueira, Ranjita Bhagwan, Keith Marzullo, Stefan Savage, Geoffrey M. Voelker
Venue:  (2003)

The Internet today is highly vulnerable to \emph{Internet catastrophes}: events in which an exceptionally successful Internet pathogen, like a worm or email virus, causes data loss on a significant percentage of the computers connected to the Internet. In this paper, we explore the feasibility of using data redundancy, a model of dependent host vulnerabilities, and distributed storage to ensure data survives such events. In particular, we motivate the design of a cooperative, peer-to-peer remote backup system called the \Phoenix\ recovery system, and we argue that \Phoenix\ is a compelling architecture for providing a convenient and effective approach for tolerating Internet catastrophes. Our key observation that makes \Phoenix\ both feasible and practical is that an Internet catastrophe, like any large-scale Internet attack, exploits shared vulnerabilities. Hence, the replication mechanism should take the dependencies of host failures---in this case, host diversity---into account. Using a simulation model we show that, by doing informed placement of replicas, \Phoenix\ provide highly reliable and available cooperative backup and recovery with low overhead: with as few as 2 replicas, the system can backup and recover at least the equivalent of 20\% of storage contributed by each host in the system.
The Impact of Artificial Intelligence on Society
Authors: Richard S. Rosenberg
Venue:  (1988)

This paper presents an introduction to a number of social issues which may arise as a result of the diffusion of Artificial Intelligence (AI) applications from the laboratory to the workplace and marketplace. Four such applications are chosen for discussion: expert systems, image processing, robotics, and natural language understanding. These are briefly characterized and possible areas of misuse are explored. Of the many social issues of concern, four are selected for treatment here as representative of other potential problems likely to follow such a powerful technology as AI. These four are work (how much and of what kind), privacy (on which the assault continues), decision-making (by whom and for whose benefit), and social organization (how in a society in which intelligent systems perform so many functions). Finally it is argued that both a major programme of study in this field be launched and that practitioners assume the responsibility to inform the public about their work.
Creating sustainable competitive advantage through internetworked communities
Authors: Ali F. Farhoomand, Pauline S. P. Ng
Venue: Communications of the ACM (2003)

Examining the effects of transforming the Hong Kong Stock Exchange from a closed to an open trading system.
Implementing Communication Protocols Using Object-Oriented Techniques
Authors: Gregory R. Lavender, Dennis G. Kafura, Chris J. Tomlinson
Venue:  (1992)

In this paper, elements of an object-oriented implementation of the upper layer OSI protocols are presented. Our goal in the paper is two-fold. First, to communicate to software engineers, particularly those developing systems software, that object-oriented programming techniques facilitate and enhance the implementation of layered architectures. Second, to convey to language designers our experience using object-oriented language features in building communications protocols. We focus on the requirements for the upper layer OSI protocols and illustrate how inheritance, subtyping, and polymorphic function effect their implementation.
METHOD INTEGRATION FOR EXPERIENCE-BASED LEARNING
Authors: Jeffrey Gould, Robert Levinson
Venue:  (1991)

This paper describes how a variety of machine learning methods can be combined synergistically to produce an adaptive pattern-oriented chess program. Major aspects of the following machine learning methods are used: temporal-difference learning, simulated annealing, genetic algorithms, explanation-based generalization, structured concept induction and heuristic evaluation. The need for these methods comes from the research constraints placed on the chess system. The system, "Morph", is limited to using just 1-ply of search, little domain knowledge and no supervised training. Thus, the system is responsible for finding a useful set of features (patterns) for evaluating states and for determining their significance (in the form of weight). To get the learning methods to cooperate effectively some design constraints normally associated with these methods need to be relaxed. The paper also argues that a benefit of a multi-strategy viewpoint is that new research ideas arise from the multiple perspectives.
Completion Energies and Scale
Authors: E. Sharon, A. Brandt, R. Basri
Venue:  (1997)

The detection of smooth curves in images and their completion over gaps are two important problems in perceptual grouping. In this study we examine the notion of completion energy of curve elements, showing and exploiting its intrinsic dependence on length and width scales. We introduce a fast method for computing the most likely completion between two elements, by developing novel analytic approximations and a fast numerical procedure for computing the curve of least energy. We then use our newly developed energies to find the most likely completions in images through a generalized summation of induction fields. This is done through multiscale procedures, i.e., separate processing at different scales with some interscale interactions. Such procedures allow the summation of all induction fields to be done in a total of only O(N logN) operations, where N is the number of pixels in the image. More important, such procedures yield a more realistic dependence of the induction field on the length and width scales: the field of a long element is very different from the sum of the fields of its composing short segments.
Invariant features for gray scale images
Authors: Hanns Schulz-Mirbach
Venue:  (1995)

In invariant features are image characteristics which remain unchanged under the action of a transformation group. We consider in this paper image rotations and translations and present algorithms for constructing invariant features. After briefly sketching the theoretical background we develop algorithms for recognizing several objects in a single scene without the necessity to segment the image beforehand. The objects can be rotated and translated independently. Moderate occlusions are tolerable. Furthermore we show how to use these techniques for the recognition of articulated objects. The methods work directly with the gray values and do not rely on the extraction of geometric primitives like edges or corners in a preprocessing step. All algorithms have been implemented and tested both on synthetic and real image data. We present some illustrative experimental results.
Software Quality Measurement: Validation of a Foundational Approach (Final Report, Year Two)
Authors: James D. Arthur, Richard E. Nance, Edward V. Dorsey
Venue:  (1992)

This report discusses the second year findings of a proposed four year investigation effort that focuses on the assessment and prediction of software quality. The research exploits fundamental linkages among software engineering Objectives, Principles, and Attributes (the OPA framework). Process and documentation quality indicators (DQI) are presented relative to the OPA framework with an elaboration on their individual role in assessing and predicting software quality. The development of a document quality analyzer is discussed, with a particular emphasis being placed on the selected subset of DQI measures that it provides.
The ASTRAL Specifications of 8 Real-Time Systems
Authors: Paul Z. Kolano
Venue:  (1999)

This report gives the ASTRAL specifications of 8 real-time systems. These systems include a bakery algorithm specification, a cruise control system, an elevator control system, an Olympic boxing scoring system, a phone system, a production cell, a railroad crossing system, and a stoplight control system.
Galois Theory for Minors of Finite Functions
Authors: Nicholas Pippenger
Venue:  (1998)

Galois Theory for Minors of Finite Functions Nicholas Pippenger A Boolean function f is a minor of a Boolean function g if f is obtained from g by substituting an argument of f, the complement of an argument of f, or a Boolean constant for each argument of g. The theory of minors has been used to study threshold functions (also known as linearly separable functions) and their generalization to functions of bounded order (where the degree of the separating polynomial is bounded, but may be greater than one). We construct a Galois theory for sets of Boolean functions closed under taking minors, as well as for a number of generalizations of this situation. In this Galois theory we take as the dual objects certain pairs of relations that we call ``constraints'''', and we explicitly determine the closure conditions on sets of constraints. 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
Dissemination of Collection Wide Information in a Distributed Information Retrieval System
Authors: Charles L. Viles, James C. French
Venue:  (1995)

We find that dissemination of collection wide information (CWI) in a distributed collection of documents is needed to achieve retrieval effectiveness comparable to a centralized collection. Complete dissemination is unnecessary. The required dissemination level depends upon how documents are allocated among sites. Low dissemination is needed for random document allocation, but higher levels are needed when documents are allocated based on content. We define parameters to control dissemination and document allocation and present results from four test collections. We define the notion of iso-knowledge lines with respect to the number of sites and level of dissemination in the distributed archive, and show empirically that iso-knowledge lines are also iso-effectiveness lines when documents are randomly allocated.
Learning-integrated interactive image segmentation
Authors: Bir Bhanu, Stephanie Fonder
Venue: Advances in evolutionary computing: theory and applications (2003)

We present an approach to automatic image segmentation, in which user-selected sets of examples and counter-examples supply information about the specific segmentation problem. In our approach, image segmentation is guided by a genetic algorithm which learns the appropriate subset and spatial combination of a collection of discriminating functions, associated with image features. The genetic algorithm encodes discriminating functions into a functional template representation, which can be applied to the input image to produce a candidate segmentation. The performance of each candidate segmentation is evaluated within the genetic algorithm, by a comparison to two physics-based techniques for region growing and edge detection. Through the process of segmentation, evaluation, and recombination, the genetic algorithm optimizes functional template design efficiently. The contributions of this chapter include: genetic learning of functional template design, physics-based segmentation evaluation, novel crossover operator and fitness function, as well as a system prototype and experiments on real synthetic aperture radar (SAR) imagery of varying complexity.
Ein konstruktiver Ansatz zur systematischen Entwicklung vonAusfuehrungsanweisungen fuer Workflows
Authors: Markus Boehm, Clemens Cap, Klaus Meyer, Stefan Jablonski
Venue:  (1998)

Durch die Verfuegbarkeit von WFMS mit erweiterbaren Workflow-Sprachen kann die Aufgabe der Sprachdefinition oder Spracherweiterung jetzt dem Entwickler der Workflow-Management-Anwendung zufallen. Dieser Technische Bericht stellt einen Ansatz fuer die Entwicklung neuer Ausfuehrungsanweisungen vor. Im Mittelpunkt steht ein Funktionsmodell, das die Funktionsweise dieser Sprachelemente auf konzeptioneller Ebene erklaert. Danach sind Ausfuehrungsanweisungen zustandstragende reaktive Objekte, die mit den Workflow-Instanzen interagieren, deren Ausfuehrung sie kontrollieren. Die Ausfuehrungsanweisung definiert in Abhaengigkeit von der intendierten Workflow-Ausfuehrung zulaessige Konstellation von Zustaenden und Zustandsuebergaengen der kontrollierten Workflow- Instanzen Mit Hilfe Verteilter Transitionssysteme wird das Funktionsmodell fuer eine konkrete Ausfuehrungsanweisung mit formalen Mitteln beschrieben. Symbolische Bezeichner fuer Zustaende der Workflow- Instanzen und der Ausfuehrungsanweisung werden zu Transitionen zusammengefasst; das Schalten einer Transition gibt zulaessige Veraenderungen des Gesamtsystems aus Workflow-Instanzen und Ausfuehrungsanweisung wieder. Die Darstellung von Ausfuehrungsanweisungen durch ein Verteiltes Transitionssystem ermoeglicht weiterhin, Eigenschaften der Ausfuehrungsanweisung abzuleiten und auf Uebereinstimmung mit den Anforderungen des Entwicklers an die Workflow-Ausfuehrung zu pruefen.
An Expert System for Hollow Extrusion Die Design
Authors: J. R. Thomas, A. G. Cohn
Venue:  (1989)

This report is based upon a project to develop a prototype expert system to design hollow extrusion dies. Input to the system consisted of a cross sectional representation of the required extruded shape. Previous reserach has concentrated on critiquing existing designs for possible areas of manufacturing difficulty but until now no one has attempted to automate the design process itself. Problems in building such a system are centred on representing and performing the required spatial reasoning, and inproducing a design which meet various conflicting design goals. Output from the prototype system consists of one or more designs which satisfied the constraints for the extrusion die. Further system development is required in order to identify the optimal design when more than one design is produced and to increasing the efficiency of the implementation.
Implementing Binary Component Adaptation for Java
Authors: Ralph Keller, Urs Holzle
Venue:  (1998)

This report gives a detailed description of our implementation of binary component adaptation (BCA) for Java. We describe the adaptation specification, its translation into the delta file, and how class files are modified during class loading. We also explain how we integrated BCA into the JDK1.1.5 and how we modified javac in order to compile against adapted classes.
Storage Schemes for Parallel Eigenvalue Algorithms
Authors: Robert A. van de Geijn
Venue:  (1988)

In this paper, we examine storage schemes for parallel implementation on distributed memory MIMD multiprocessors of algorithms for solving the algebraic eigenvalue problem. We show that a novel storage scheme, which we call block hankel-wrapped storage, allows better utilization of the processors than column-wrapped storage when implementing Jacobi''s Method or the nonsymmetric QR algorithm.
Modeling Positional Uncertainty in Object Recognition
Authors: Arthur R. Pope, David G. Lowe
Venue:  (1994)

Iterative alignment is one method for feature-based matching of an image and a model for the purpose of object recognition. The method alternately hypothesizes feature pairings and estimates a viewpoint transformation from those pairings; at each stage a refined transformation estimate is used to suggest additional pairings. This paper extends iterative alignment in the domain of 2D similarity transformations so that it represents the uncertainty in the position of each model and image feature, and that of the transformation estimate. A model describes probabilistically the significance, position, and intrinsic attributes of each feature, plus topological relations among features. A measure of the match between a model and an image integrates all four of these, and leads to an efficient matching procedure called probabilistic alignment. That procedure supports both recognition and a learning procedure for acquiring models from training images. By explicitly representing uncertainty, one model can satisfactorily describe appearance over a wider range of viewing conditions. Thus, when models represent 2D characteristic views of a 3D object, fewer models are needed. Experiments demonstrating the effectiveness of this approach are reported.
Invariants for the Recognition of Planar Contour and Gray-Scale Images
Authors: Hans Burkhardt, Axel Fenske, Hanns Schulz-Mirbach
Venue:  (1992)

The paper gives some results for the construction, the existence and the properties of invariants for the recognition of planar contour and gray-scale images. We consider planar and spatial motion of rigid objects (Euclidean motion) with orthographic projection into the camera plane which define corresponding equivalence classes. Different performance measures of the invariant features like completeness, robustness as well as the matter of computational complexity are discussed.
Real Time Threads Interface
Authors: David Finkelstein, Norman C. Hutchinson, Dwight J. Makaroff
Venue:  (1995)

The Real Time Threads package (abbreviated RT Threads) provides a user-level, preemptive kernel running inside a single address space (e.g., within a UNIX process). RT Threads implements thread management, synchronization, and communication functions, including communication between RT Threads environments (i.e., with different address spaces, possibly on different machines and different architectures). Threads are scheduled using a real-time, multi-priority, preemptive scheduling algorithm. Each thread is scheduled on the basis of its modifiable scheduling attributes: starting time, priority and deadline. No thread is scheduled before its starting time. Schedulable threads (i.e., threads whose starting time has passed) are scheduled on a highest priority first basis. Schedulable threads of equal priority use an earliest deadline first (EDF) scheduling policy. An RT Threads environment is cooperative in the sense that memory is shared among all threads, and each thread runs to completion unless preempted on the basis of priorities and deadlines. Alternate scheduling policies, such as time slicing, can be implemented at the application level using the scheduling mechanisms provided by RT Threads. This report describes the interface to the RT Threads package.