ppxscal/embedding_network huggingface dataset:
DSS structure and algorithmic transparency in APL
Authors: W. E. Cundiff
Venue: Proceedings of the international conference on APL '91 (1991)

Earlier discussion focused on APL as an executable notation for understanding the inner-workings of dialogue generation and data/model base management in Decision Support Systems (DSS). The present work applies the notion of algorithmic transparency to the broader properties of system structure that connect the technology components of DSS. Using a concise set of idioms, embodying only the control construct of sequence, APL's direct definition form is employed in revealing patterns in the specification of a functional prototype Group DSS (GDSS).
A Comparative Study of Two Search Strategies for Connected Word Recognition: Dynamic Programming and Heuristic Search
Authors: Hermann Ney
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (1992)

A most successful approach to recognizing continuous speech is to model the recognition problem as one of finding an optimal path through a finite state network. A comparison of two search strategies for finding the optimal path, dynamic programming and heuristic search, is presented. The comparison is based on theoretical considerations and experimental tests on a digit string task.
Concurrency object-oriented programming
Authors: Michael L. Nelson
Venue: ACM SIGPLAN Notices (1991)

This paper serves as an introduction to concurrent and distributed object-oriented systems. This is a relatively new area, with few commercially available systems. Even those systems that are available have not yet stood up to the 'test of time'. Available information on those few systems that are commercially available, as well as several research efforts, is summarized and analyzed.
From document to knowledge base: intelligent hypertext as minimalist instruction
Authors: Patricia A. Carlson
Venue: ACM SIGDOC Asterisk Journal of Computer Documentation (1992)

In The N uuml;rnberg Funnel: Designing Minimalist Instruction for Practical Computer Skill, John Carroll builds a case for online training as a replacement for a user's manual, a traditional part of the paper library for computer products. In this commentary, I too will argue for a type of minimalist online tutorial as the primary means of user support, but I'll suggest something far different from the "minimal manual."
Manipulation of terrain data for a real-time display application
Authors: J. R. Vaughan, G. R. Brookes, M. A. Fletcher, D. P. M. Wills
Venue: Microprocessors Microsystems (1991)

There is a need for a graphics display for data which is stored as a terrain data base. Due to space and cost limitations of the application, a system has been developed to work on a microcomputer system which includes transputers to allow parallel processing. This paper describes the data representation and manipulation which has been taken in order to provide a real-time graphical display. This data representation is suitable for use in a parallel processing environment. &mdash;From the Abstract
Minimax Search Algorithms With and Without Aspiration Windows
Authors: Hermann Kaindl, Reza Shams, Helmut Horacek
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (1991)

Investigation of several algorithms for computing exact minimax values of game trees (utilizing backward pruning) are discussed. The focus is on trees with an ordering similar to that actually found in game playing practice. The authors compare the algorithms using two different distributions of the static values, the uniform distribution and a distribution estimated from practical data. A systematic comparison of using aspiration windows for all of the usual minimax algorithms is presented. The effects of aspiration windows of varying size and position are analyzed. Increasing the ordering of moves to near the optimum results in unexpectedly high savings. Algorithms with linear space complexity benefit most. Although the ordering of the first move is of predominant importance, that of the remainder has only second-order effects. The use of an aspiration window not only makes alpha-beta search competitive, but there also exist dependencies of its effects on certain properties of the trees.
Estimating the Kinematics and Structure of a Rigid Object from a Sequence of Monocular Images
Authors: Ted J. Broida, Rama Chellappa
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (1991)

The problem considered involves the use of a sequence of noisy monocular images of a three-dimensional moving object to estimate both its structure and kinematics. The object is assumed to be rigid, and its motion is assumed to be smooth. A set of object match points is assumed to be available, consisting of fixed features on the object, the image plane coordinates of which have been extracted from successive images in the sequence. Structure is defined as the 3-D positions of these object feature points, relative to each other. Rotational motion occurs about the origin of an object-centered coordinate system, while translational motion is that of the origin of this coordinate system. In this work, which is a continuation of the research done by the authors and reported previously, results of an experiment with real imagery are presented, involving estimation of 28 unknown translational, rotational, and structural parameters, based on 12 images with seven feature points.
Implementing a random number package with splitting facilities
Authors: Pierre L'Ecuyer, Serge Côté
Venue: ACM Transactions on Mathematical Software (TOMS) (1991)

A portable set of software tools is described for uniform random variates generation. It provides for multiple generators running simultaneously, and each generator has its sequence of numbers partitioned into many long (disjoint) substreams. Simple procedure calls allow the user to make any generator &ldquo;jump&rdquo; ahead to the beginning of its next substream, back to the beginning of its current substream, or back to the beginning of its first substream.&hellip; Implementation issues are discussed.&hellip;A Pascal implementation for 32-bit computers is described. &mdash;From the Authors' Abstract
Cost-performance analysis of heterogeneity in supercomputer architectures
Authors: Daniel Menascé, Virgílio Almeida
Venue: Proceedings of the 1990 ACM/IEEE conference on Supercomputing (1990)

Heterogeneity has appeared as a cost-effective approach to design high performance computers. This paper analyzes cost-performance of heterogeneity in supercomputer architectures. Queueing models are used to study performance of homogeneous and heterogeneous supercomputer models. Grosch's Law, which states that computer performance increases as the square of its cost, is used to analyze cost aspects of the models. The results of this paper show that heterogeneity in supercomputer architectures is a quite promising design approach that deserves further investigation.
A performance evaluation model for a digital group with multislot traffic streams
Authors: D. Medhi, A. van de Liefvoort, C. S. Reece
Venue: Proceedings of the 1992 ACM annual conference on Communications (1992)

We present a unified model to compute various performance measures when a mixture of multi-slot traffic streams is offered on a trunk group of an integrated digital network under various bandwidth control schemes. When we considered a bandwidth reservation scheme based on traditional trunk reservation and a variation called partial bandwidth reservation, we have observed that the performance criteria themselves has significant impact in deciding which reservation scheme to use and at what level to use.
Reasoning about functional dependencies generalized for semantic data models
Authors: Grant E. Weddell
Venue: ACM Transactions on Database Systems (TODS) (1992)

We propose a more general form of functional dependency for semantic data models that derives from their common feature in which the separate notions of domain and relation in the relational model are combined into a single notion of class. This usually results in a richer terminological component for their query languages, whereby terms may navigate through any number of properties, including none. We prove the richer expressiveness of this more general functional dependency, and exhibit a sound and complete set of inference axioms. Although the general problem of decidability of their logical implication remains open at this time, we present decision procedures for cases in which the dependencies included in a schema correspond to keys, or in which the schema itself is acyclic. The theory is then extended to include a form of conjunctive query. Of particular significance is that the query becomes an additional source of functional dependency. Finally, we outline several applications of the theory to various problems in physical design and in query optimization. The applications derive from an ability to predict when a query can have at most one solution.
Principles and realization strategies of multilevel transaction management
Authors: Gerhard Weikum
Venue: ACM Transactions on Database Systems (TODS) (1991)

One of the demands of database system transaction management is to achieve a high degree of concurrency by taking into consideration the semantics of high-level operations. On the other hand, the implementation of such operations must pay attention to conflicts on the storage representation levels below. To meet these requirements in a layered architecture, we propose a multilevel transaction management utilizing layer-specific semantics. Based on the theoretical notion of multilevel serializability, a family of concurrency control strategies is developed. Suitable recovery protocols are investigated for aborting single transactions and for restarting the system after a crash. The choice of levels involved in a multilevel transaction strategy reveals an inherent trade-off between increased concurrency and growing recovery costs. A series of measurements has been performed in order to compare several strategies. Preliminary results indicate considerable performance gains of the multilevel transaction approach.
The complexity of deciding consistency of systems of polynomials in exponent inequalities
Authors: Nikolaj N. Vorobjov,  Jr.
Venue: Journal of Symbolic Computation (1992)

Suppose the polynomials P"1..., P"k@?@?[X"1,...,X"n, U], h@?@?[X"1,...,X"n] have degrees deg(P"i), deg(h)=0,...,P"k(X"1,...,X"n, e^h^(^X^"^1^,^...^,^X^"^n)>=0 within time polynomial in M(nkd)^n^^^4.
Dynamic load balancing in distributed real-time systems (abstract)
Authors: M. Bozyigit, M. Melhi
Venue: Proceedings of the 1990 ACM annual conference on Cooperation (1990)

In this study, load balancing aspect of distributed real-time systems subject to dynamic changes is discussed. Real-time distributed systems, especially in applications such as automated/computerized factory environment, are often prone to load changes through out their long operational life period. Load changes in such systems may be deterministic as well as random. Three types of changes are possible. (1) the existing modules constituting such systems may complete their mission at a point in time and terminate. (2) some other modules may have lend themselves into existence triggered by a signal or a call from another module. (2) some modules may undergo significant increase or reductions in the volume of execution and/or communication requirements. These changes can upset the existing balance in load distribution over the system, thus prolong the tasks involved. The objective is thus to investigate near optimal heuristic solutions to handle the problem for n-module and m-processor applications. The optimal solution to the problem of load balancing is so far found NP-hard for more than 3 processors. A survey of studies in the field of load balancing has shown that heuristic methods can give near optimal or in some cases optimal results. In our study, the load requirements of a m-module and n-processor distributed system, where m can be greater than n, are decomposed into phases. Each phase is assumed to be relatively balanced. An incremental heuristic refinement algorithm is used to find near optimal solution within a single phase. The algorithm is being extended to cover multiphase case. The results of experiments on the incremental heuristic refinement algorithm have shown 60% optimal results over 313 different runs. Key words: Load balancing, distributed realtime system, graph theoretic, linear and nonlinear programming, NP-hard, incremental heuristic refinement algorithm.
Efficient antialiased rendering of 3-D linear fractals
Authors: John C. Hart, Thomas A. DeFanti
Venue: ACM SIGGRAPH Computer Graphics (1991)

Object instancing is the efficient method of representing an hierarchical object with a directed graph instead of a tree. If this graph contains a cycle then the object it represents is a linear fractal. Linear fractals are difficult to render for three specific reasons: (1) ray-fractal intersection is not trivial, (2) surface normals are undefined and (3) the object aliases at all sampling resolutions.Ray-fractal intersections are efficiently approximated to sub-pixel accuracy using procedural bounding volumes and a careful determination of the size of a pixel, giving the perception that the surface is infinitely detailed. Furthermore, a surface normal for these non-differentiable surfaces is defined and analyzed. Finally, the concept of antialiasing "covers" is adapted and used to solve the problem of sampling fractal surfaces.An initial bounding volume estimation method is also described, allowing a linear fractal to be rendered given only its iterated, function system. A parallel implementation of these methods is described and applications of these results to the rendering of other fractal models are given.
1991 SIGGRAPH Educators' Slide Set
Authors: Steve Cunningham
Venue: ACM SIGGRAPH Computer Graphics (1991)

SIGGRAPH'91 and its fixst-ever educators' program is also accompanied by the first SIGGRAPH Educators' Slide Set. This set is intended to provide instructors with sets of slides that support common subjects in computer graphics courses at all levels. In this first year, we are pleased to cover three topics that should be of interest to instructors at many levels and in many subject areas. The areas are outlined below.Interested instructors are encouraged to contact the editor if they have or are planning to prepare instructional slides on an area of computer graphics. We would like to continue to provide educational resources for computer graphics. This year marks the first educators' slide set, but we do not want it to be the last!
A balanced approach to first-year computer science
Authors: David G. Kay
Venue: Proceedings of the twenty-third SIGCSE technical symposium on Computer science education (1992)

We describe a first-year course sequence for computer science majors that covers most of the traditional first-year concepts, providing a balance between formal analysis and software synthesis, with examples and assignments in three high-level programming languages: Pascal, Scheme (a lexically scoped dialect of Lisp), and C. We argue that this balanced, tri-lingual approach promotes more effective pedagogy and provides students with a broader foundation than does an all-formal, all-programming, or single-language focus.
Making abduction more efficient
Authors: Douglas Appelt, Jerry R. Hobbs
Venue: Proceedings of the workshop on Speech and Natural Language (1990)

The TACITUS system uses a cost-based abduction scheme for finding and choosing among possible interpretations for natural language texts. Ordinary Prolog-style, backchaining deduction is augmented with the capability of making assumptions and of factoring two goal literals that are unifiable (see Hobbs et al., 1988).
Discrete and Continuous Models for the Performance of Reconfigurable Multistage Systems
Authors: Israel Koren, Zahava Koren
Venue: IEEE Transactions on Computers (1991)

The authors analyze the performance of multiprocessor systems with a multistage interconnection network in the presence of faulty components. Models for estimating the system performance, as measured by its bandwidth and processing power, are developed for two different modes of operation. In the first mode, the operation of the system is fully synchronized and all processors which require memory access issue their requests simultaneously. In the second, each processor is allowed to issue its request at any time instant. For each of the two modes of operation, two models are presented providing lower and upper estimates for the bandwidth of multistage systems and an upper estimate for their processing power. The operation of 16*16 synchronous and asynchronous reconfigurable systems has been simulated and the bandwidth and processing power have been calculated.
Subdomain dependence test for massive parallelism
Authors: Lee-Chung Lu, Marina C. Chen
Venue: Proceedings of the 1990 ACM/IEEE conference on Supercomputing (1990)

The dependence analysis and testing problem has been well studied in parallelizing compilers. All of the existing dependence decision algorithms, however, are conservative in considering data dependence between statements occurring in conditional branches. We present a new dependence test which can detect disjoint regions of an iteration space, and therefore reports accurate dependencies for a class of conditional statements.
Practical Issues in Temporal Difference Learning
Authors: Gerald Tesauro
Venue: Machine Learning (1992)

This paper examines whether temporal difference methods for training connectionist networks, such as Sutton's TD(&lambda;) algorithm, can be successfully applied to complex real-world problems. A number of important practical issues are identified and discussed from a general theoretical perspective. These practical issues are then examined in the context of a case study in which TD(&lambda;) is applied to learning the game of backgammon from the outcome of self-play. This is apparently the first application of this algorithm to a complex non-trivial task. It is found that, with zero knowledge built in, the network is able to learn from scratch to play the entire game at a fairly strong intermediate level of performance, which is clearly better than conventional commercial programs, and which in fact surpasses comparable networks trained on a massive human expert data set. This indicates that TD learning may work better in practice than one would expect based on current theory, and it suggests that further analysis of TD methods, as well as applications in other complex domains, may be worth investigating.
On bulk data type constructors and manipulation primitives: a framework for analyzing expressive power and complexity
Authors: Richard Hull, Jianwen Su
Venue: Proceedings of the second international workshop on Database programming languages (1989)

We present a framework for analyzing the complexity and expressive power of many existing languages for manipulating information in bulk data types. The framework is based on four dimensions: the &ldquo;cardinality measure&rdquo; of the underlying data model; procedural vs. declarative; the presence of iteration; and the presence of &ldquo;invention&rdquo;. Several languages from the literature which correspond to various combinations of these dimensions are categorized into five families of queries, ranging from QLOGSPACE to a family which is more expressive than the computable queries.
Managing hard-disk PCs in the introductory laboratory
Authors: David K. Walker, David S. Tucker
Venue: ACM SIGCSE Bulletin (1991)

A method is described for managing stand-alone hard-disk PCs, in an environment in which students are allowed to explore the hard disk. The system, application, and student-created files are safeguarded by management software which helps eliminate "accidental" loss or modification.
Estimation of Illuminant Direction, Albedo, and Shape from Shading
Authors: Qinfen Zheng, Rama Chellappa
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (1991)

A robust approach to the recovery of shape from shading information is presented. Assuming uniform albedo and Lambertian surface for the imaging model, two methods for estimating the azimuth of the illuminant are presented. One is based on local estimates on smooth patches, and the other method uses shading information along image contours. The elevation of the illuminant and surface albedo are estimated from image statistics, taking into consideration the effect of self-shadowing. With the estimated reflectance map parameters, the authors then compute the surface shape using a procedure that implements the smoothness constraint by requiring the gradients of reconstructed density to be close to the gradients of the input image. The algorithm is data driven, stable, updates the surface slope and height maps simultaneously, and significantly reduces the residual errors in irradiance and integrability terms. A hierarchical implementation of the algorithm is presented. Typical results on synthetic and images are given to illustrate the usefulness of the approach.
A Theory of Reduced and Minimal Procedural Dependencies
Authors: Augustus K. Uht
Venue: IEEE Transactions on Computers (1991)

A reduced set of procedural dependencies is presented which is necessary and sufficient to describe all procedural dependencies in standard imperative codes. Hence, the set is minimal. In conjunction with reduced data dependencies, this set forms a set of minimal semantic dependencies for all traditional code. It is also shown that all forward branches in structured code are procedurally independent. The effects of limited hardware are also addressed. A possible implementation of a machine enforcing just the minimal procedural dependencies is described.
BIST PLAs, pass or fail&mdash;a case study
Authors: Shambhu J. Upadhyaya, John A. Thodiyil
Venue: Proceedings of the 27th ACM/IEEE Design Automation Conference (1991)

Numerous Built-In Self Testing (BIST) designs now exist for the testing of Programmable Logic Arrays (PLA), but their practical usefulness has not been studied. In this paper, we implement and compare several BIST designs using a common methodology of implementation. We also perform an yield analysis to characterize the yield degradation due to the BIST design methodology. Our preliminary findings of this work is that BIST approach results in considerable degradation of yield, and therefore may not be suitable as a test vehicle for PLAs.
The correlation quiz: an aid in curbing cheating in programming assignments
Authors: Diana T. Dadamo
Venue: ACM SIGCSE Bulletin (1990)

In order to develop programming ability, computer science courses typically include a number of out-of-class assignments. To motivate the students in completing these assignments, these projects are usually graded and the values included in the computation of the final grade for the course. However, the amount of cheating done on the programming assignments makes it unfair to heavily weigh these values. Some systems of grading have been developed that downplay the effect of the programming assignment grades but this negates the effort of the students and the importance of developing the practical aspects of a programming language. Within the constraints of an out-of-class programming assignment, this paper proposes a new system that can potentially reduce the incidence of cheating while requiring honest students to review their program after completion. (The development of the Correlation quiz was done while the author was a Senior Lecturer at Widener University.)