ppxscal/embedding_network huggingface dataset:
Object Code Verification
Authors: Wahab,  M
Venue:  (1998)

Object code is a program of a processor language and can be directly executed on a machine. Program verification constructs a formal proof that a program correctly implements its specification. Verifying object code therefore ensures that the program which is to be executed on a machine is correct. However, the nature of processor languages makes it difficult to specify and reason about object code programs in a formal system of logic. Furthermore, a proof of the correctness of an object code program will often be too large to construct manually because of the size of object code programs. The presence of pointers and computed jumps in object code programs constrains the use of automated tools to simplify object code verification. This thesis develops an abstract language which is expressive enough to describe any sequential object code program. The abstract language supports the definition of program logics in which to specify and verify object code programs. This allows the object code programs of any processor language to be verified in a single system of logic. The abstract language is expressive enough that a single command is enough to describe the behaviour of any processor instruction. An object code program can therefore be translated to the abstract language by replacing each instruction with the equivalent command of the abstract language. This ensures that the use of the abstract language does not increase the difficulty of verifying an object code program. The verification of an object code program can be simplified by constructing an abstraction of the program and showing that the abstraction correctly implements the program specification. Methods for abstracting programs of the abstract language are developed which consider only the text of a program. These methods are based on describing a finite sequence of commands as a single, equivalent, command of the abstract language. This is used to define transformations which abstract a program by replacing groups of program commands with a single command. The abstraction of a program formed in this way can be verified in the same system of logic as the original program. Because the transformations consider only the program text, they are suitable for efficient mechanisation in an automated proof tool. By reducing the number of commands which must be considered, these methods can reduce the manual work needed to verify a program. The use of an abstract language allows object code programs to be specified and verified in a system of logic while the use of abstraction to simplify programs makes verification practical. As examples, object code programs for two different processors are modelled, abstracted and verified in terms of the abstract language. Features of processor languages and of object code programs which affect verification and abstraction are also summarised. 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
A Collection of Two-Player Games on Cellular Automata
Authors: A. S. Fraenkel
Venue:  (2000)

We define a two-player cellular automata game played on a finite cyclic digraph G = (V,E). Each vertex assumes a weight w I {0,1}. A move consists of selecting a vertex u with w(u) = 1 and firing it, i.e., complementing its weight and that of a selected neighborhood of u. The player first making all weights 0 wins, and the opponent loses. If there is no last move, the outcome is a draw. Giving a minimum of the underlying theory, we exhibit the nature of the games on hand of examples. The 3-fold motivation for exploring these games stems from complexity considerations in combinatorial game theory, transforming the hitherto solitaire cellular automata games into two-player games, and the theory of linear error correcting codes.
The Psychology of Visualization
Authors: Andrew Csinger
Venue:  (1992)

The Psychology of Visualization This document is a review of the literature of three related areas: psychophysical vision research, automatic display generation, and multi-dimensional data visualization. Common threads are explored, and a model of the visualization process is proposed which integrates aspects of these three areas. In the review of psychophysics, attempts to find a set of primitive perceptual channels are explored. In the literature on automatic generation and visualization, attempts to employ these psychophysical findings are investigated. Finally, the proposed model is a framework which might facilitate this kind of cooperation.
Path Planning Through Time and Space in Dynamic Domains
Authors: Marc G. Slack, David P. Miller
Venue:  (1987)

Realistic robot problems involve navigating the robot through time as well as space. The obstacles that a robot must avoid and the pathways on which it travels are subject to changes throughout time. These changes can occur in a predictable or unpredictable fashion. This paper presents an integrated route planning and spatial representation system that allows paths to be calculated in dynamic domains. The path planner finds the "best route" through a given n-dimensional space. The "best route" is defined as the path through space-time with the best score as determined by a set of user-defined evaluation
Multi-evidential Correlation \& Visual Echo Analysis
Authors: B, Esf ari, iar, James J. Little
Venue:  (1993)

Visual motion, stereo, texture, and symmetric boundaries are all repetition of similar patterns in time or space. These repetitions can be viewed as "echoes" of one another, and the measurement of disparities, segmentation of textons, or detection of boundary symmetries translates into detection of echo arrival periods. Cepstral filtering, as well as Polyspectral techniques and waveform analysis, are some of the techniques used successfully for echo detection. This paper examines the application of cepstral analysis to computational vision, introduces modified improvements to the traditional methods, and provides a comparison with other routines presently used. Finally, we introduce a general multi-evidential correlation approach which lends itself to several computational routines. CepsCorr, as we call it, is a simple general technique that can accept different matching routines, such as cepstrum and/or phase correlation as its measurement kernel. The evidences provided by each iteration of cepsCorr can then be combined to provide a more accurate estimate of motion or binocular disparity.
Human Factors and Software Reuse: The Manager''s Impact
Authors: John A. Lewis, Sallie M. Henry, Dennis G. Kafura, Robert S. Schulman
Venue:  (1992)

This paper describes the results of a controlled experiment designed to evaluate the impact of human factors on software reuse. The experiment concludes that (1) software reuse promotes higher productivity than no reuse, (2) reuse resulting from both moderate and strong encouragement promote higher productivity than no reuse, and (3) while strong managerial encouragement did not create a significant difference in productivity, it does tend to promote improper reuse activities.
Objects in the Pi-calculus
Authors: D. J. Walker
Venue:  (1992)

Two semantics for a parallel object-oriented programming language are presented. One is a two-level transitional semantics in which the global behaviour of a system is derived directly from the possible actions of its constituent objects. The other is by translation into the pi-calculus. A close correspondence between the semantics is established.
Guidelines for Selecting and Using Simulation Model Verification Techniques
Authors: Richard B. Whitner, Osman Balci
Venue:  (1989)

There is a lack of sufficient understanding and realization of the importance of simulation model verification in the simulation community. The demands placed on the software which serves as a computer-executable representation of a simulation model are increasing. In the field of software engineering, there is an abundance of software verification techniques that are applicable for simulation model verification. This paper is intended to reduce the communication gap between the software engineering and simulation communities by presenting software verification techniques applicable for simulation model verification in a terminology understandable by a simulationist. A taxonomy of verification techniques is developed to guide the simulationist in selecting and using such techniques. Characteristics, advantages, and disadvantages of verification techniques under each category are described.
Implicit integration of elastoplastic constitutive equations of interface elements
Authors: F. Cai, K. Ugai
Venue: Proceedings of the eighth international conference on The application of artificial intelligence to civil and structural engineering computing (2001)

The implicit integration algorithm for elastoplastic constitutive equations of interface element describes in this paper. It is indicated that the omission of the second derivatives of the plastic potential induces the convergence difficulty when the shear stress in the three-dimensional interface element is small, which appears usually in the soil-structure interaction analysis when the structure is laterally loaded. The second derivatives of the plastic potential are obtained for the elastoplastic constitutive equations of interface element. The proposed implicit integration algorithm for elastoplastic constitutive equations of interface element is confirmed with a benchmark, and used to analyse the response of flexible piles in landslides.
BeeHive: Global Multimedia Database Support for Dependable, Real-Time Applications
Authors: John A. Stankovic, Sang H. Son, Jorg Liebeherr
Venue:  (1997)

The confluence of computers, communications and databases is quickly creating a global virtual database where many applications require real-time access to both temporally accurate and multimedia data. We are developing a global virtual database, called BeeHive, which is enterprise specific and offers features along real-time, fault tolerance, quality of service for audio and video, and security dimensions. Support of all these features and tradeoffs between them will provide significant improvement in performance and functionality over browsers, browsers connected to databases, and, in general, today''s distributed databases. We present a high level design for BeeHive and various novel component technologies that are to be incorporated into BeeHive.
ANALYSIS OF REPLICATION CONTROL PROTOCOLS
Authors: Darrell D. E. Long
Venue:  (1990)

In recent years many replication control protocols have been proposed, but too often these protocols are presented with insufficient evidence to demonstrate superiority over existing protocols. In this article, some simple analytical tools are presented that allow replication control protocols to be compared. A *dynamic voting* protocol is used as an example, but these techniques can be successfully applied to many other protocols as well. 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
Analysis of Structured Texture Using the Multiresolution Fourier Transform
Authors: Tao Hsu, A. D. Calway, R. G. Wilson
Venue:  (1992)

A multiresolution approach to the analysis of structural texture is presented. The multiresolution Fourier transform (MFT) is utilized as a framework to derive a robust algorithm which estimates textural features over a range of spatial scales based on local frequency domain properties. A pair of centroids of local spectra are extracted to represent the dominant frequencies of underlying spatial regions which are equivariant to rotation and scaling. Based on these centroids, the relationship between two different local spectra is characterized by an affine transformation. Assessment of the estimated affine transform is made by normalized correlation, which also provides local phase shift information. Analysis and synthesis of both artificial and natural images demonstrate the capability of the algorithm.
Generic Flaw Detection within Images
Authors: Paul S Williams, Mike Alder
Venue:  (1995)

This paper looks at the problem of detecting flaws or anomalies in greyscale images. A generic approach is adopted which uses little prior knowledge of the type of image. We assume only that most of the image will consist of `background'', and that any anomaly will be relatively small in area. The methods explored involve extracting localised, but scale invariant features from an image and expressing them as a set of higher level entities, a process called the {\em UpWrite}. Once this has been achieved data points may be further UpWritten or simply classified. This paper describes an effective and generic method used to locate anomalies in images. This is demonstrated through examples using images varying in size, scale, intensity and features, but with no programming or parameter modifications. It is conjectured that the local processing performed here is a model for the behaviour of neurons in the visual system.
PLANAR INTERCHANGEABLE 2-TERMINAL ROUTING
Authors: Man Yu, Joel Darnauer, Wayne W Dai
Venue:  (1995)

Many practical routing problems such as BGA, PGA and test fixture routing involve routing two-terminal nets on a plane with exchangeable pins. In this paper, we unify these different problems as instances of the Planar Interchangeable 2-Terminal Routing (PI2TR) problem. We formulate the problem as flows in a routing network. Secondly, we show that PI2TR is NP-complete by reduction from satisfiability. Finally, we show experimental evidence that a simple min-cost flow heuristic considering only the most important cuts in the design can quickly produce routable results in most practical cases. The flow formulation can be generalized to multiple layers with no additional vias.
Choosing the Right Neighbourhood: a Way to Improve a Stochastic Local Search Algorithm
Authors: D. C. Tulpan, H. Hoos
Venue:  (2002)

We present results on increasing the performance of a stochastic local search algorithm for the design of DNA codes, namely sets of equal-length words over the nucleotides alphabet $\{A,C,G,T\}$ that satisfy certain combinatorial constraints. Using empirical analysis of the algorithm, we gain insight on good design principles and in turn improve the performance of the SLS algorithm. We report several cases in which our algorithm finds word sets that match or exceed the best previously known constructions.
Design Automation for Finite State Machine Predictors
Authors: Timothy Sherwood, Brad Calder
Venue:  (2000)

Finite State Machines (FSM) are a fundamental building block in computer architecture, and are used to control and optimize all types of prediction and speculation. These include branch prediction, confidence estimation, value prediction, memory disambiguation, thread speculation, power optimization, and the list goes on. At the heart of all almost all of these techniques is a FSM, such as a two bit saturating counter, which is predicting a sequence given feedback information. In this paper we present a framework for automatically designing FSM predictors. This approach can be used to develop FSM predictors that perform well over a suite of applications, tailored to a specific application, or even a specific instruction. We examine the ability to create FSM predictors optimized for a group of applications for branch prediction and for confidence estimation used in value prediction.
An Analysis of Buffer Sharing and Prefetching Techniques for Multimedia Systems
Authors: Raymond T. Ng, Jinhai Yang
Venue:  (1994)

In this paper, we study the problem of how to maximize the throughput of a continuous-media system, given a fixed amount of buffer space and disk bandwidth both pre-determined at design-time. Our approach is to maximize the utilizations of disk and buffers. We propose doing so in two ways. First, we analyze a scheme that allows multiple streams to share buffers. Our analysis and preliminary simulation results indicate that buffer sharing could lead to as much as 50\% reduction in total buffer requirement. Second, we develop three prefetching strategies: SP, IP1 and IP2. As will be demonstrated by SP, straightforward prefetching is not effective at all. In contrast, IP1 and IP2, which prefetch more intelligently than does SP, could be valuable in maximizing the effective use of buffers and disk. Our preliminary simulation results show that IP1 and IP2 could lead to a 40\% improvement in throughput.
Performance of Some CFD Codes on the Alliant FX/8
Authors: Walid Abu-Sufah, Amjad M. Daoud
Venue:  (1988)

Three CFD codes are ported to the Alliant FX/8. The first solves the 3-D unsteady Euler equations using an explicit finite-volume Runge-Kutta time stepping method. The second solves the same problem using the Beam and Worming implicit method. The third is ARC2D from NASA Ames which solves the unsteady 2-D Navier-Stockes equations using an implicit method. Extensive observations and results on the performance of these codes on the FX/8 are presented. Careful interaction with parallelizing compiler improves the performance some. Better results are obtained by simple recoding of different segments in the programs.
A Theory of Multi-Scale Curvature-Based Shape Representation for Planar Curves
Authors: Farzin Mokhtarian, Alan K. Mackworth
Venue:  (1989)

This paper presents a multi-scale, curvature-based shape representation technique for planar curves which satisfies several criteria, considered necessary for any shape representation method, better than other shape representation techniques. As a result, the representation is suitable for tasks which call for recognition of a noisy curve of arbitrary shape at an arbitrary scale or orientation. \n The method rests on the concept of describing a curve at varying levels of detail using features that are invariant with respect to transformations which do not change the shape of the curve. Three different ways of computing the representation are described in this paper. These three methods result in three different representations: the curvature scale space image, the renormalized curvature scale space image, and the resampled curvature scale space image. \n The process of describing a curve at increasing levels of abstraction is referred to as the evolution of that curve. Several evolution properties of planar curves are described in this paper. Some of these properties show that evolution is a physically plausible operation and characterize possible behaviours of planar curves during evolution. Some show that the representations proposed in this paper in fact satisfy some of the required criteria. Others impose constraints on the location of a planar curve as it evolves. Together, these evolution properties provide a theoretical foundation for the representation methods introduced in this paper.
Linear Time Distance Transforms for Quadtrees
Authors: Clifford A. Shaffer, Quentin F. Stout
Venue:  (1989)

Linear time algorithms are given for computing the chessboard distance transform for both pointer-based and linear quadtree representations. Comparisons between algorithmic styles for the two representations are made. Both versions of the algorithm consist of a pair of tree traversals.
Experimental Evaluation and Comparisons of Algorithms for Incremental GraphBiconnectivity
Authors: Ramgopal Mettu, Yuke Zhao, Vijaya Ramachandran
Venue:  (1997)

We describe our implementation of an algorithm to maintain the connected components and the biconnected components of a graph where vertex and edge insertions are allowed. Algorithms for this problem can be applied to task decomposition in engineering design. Connected components are maintained using a disjoint set data structure and the biconnected components are maintained by a block forest. We implemented an incremental biconnectivity algorithm presented in Westbrook and Tarjan [8] which runs in O(n log n + m) time, where n is the number of vertices and m is the number of operations. However, the algorithm in [8] does not address the issue of deletions in disjoint sets, which seem to be needed in order to implement the algorithm correctly. Hence we develop the concepts of dynamic holes and static holes to support variations of the standard disjoint set structure that allow the deletion of certain elements. We present four different implementations of the incremental biconnectivity algorithm which utilize these variants of the standard disjoint set structure, and analyze their performance. We present extensive timing information for each of these implementations. TR97-17a contains the write-up and TR97-17b contains the graphs.
A New Basis Implementation for a Mixed Order Boundary Value ODE Solver
Authors: Uri Ascher, G. Bader
Venue:  (1985)

The numerical approximation of mixed order systems of multipoint value ordinary differential equations by collocation requires appropriate representation of the piecewise polynomial solutions. B-splines were originally implemented in the general purpose code COLSYS, but better alternatives exist. One promising alternative as proposed by Osborne and discussed by Ascher, Pruess and Russell. In this paper we analyze the performance of the latter solution representation for cases not previously covered, where the mesh is not necessarily dense. This analysis and other considerations have led us to implement a basis replacement in COLSYS and we discuss some implementation details. Numerical results are given which demonstrate the improvement in performance of the code.
The ADORA Approach to Object-Oriented Modeling of Software
Authors: Martin Glinz, Stefan Berner, Johannes Ryser, Stefan Joos, Nancy Schett, Reto Schmid, Yong Xia
Venue:  (2000)

In this paper, we present the ADORA approach to object-oriented modeling of software (ADORA stands for Analysis and Description of Requirements and Architecture). The main features of ADORA that distinguish it from other approaches like UML are the use of abstract objects (instead of classes) as the basis of the model, a systematic hierarchical decomposition of the modeled system and the integration of all aspects of the system in one coherent model. The paper introduces the concepts of ADORA and the rationale behind them, gives an overview of the language, sketches a novel concept for visualizing the model hierarchy with a tool and reports the results of a validation experiment for the ADORA language.