ppxscal/embedding_network huggingface dataset:
Recent progress in the SPHINX Speech Recognition system
Authors: Kai-Fu Lee, Hsiao-Wuen Hon, Mei-Yuh Hwang
Venue: Proceedings of the workshop on Speech and Natural Language (1989)

This paper describes recent improvements in the SPHINX Speech Recognition System. These enhancements include function-phrase modeling, between-word coarticulation modeling, and corrective training. On the DARPA resource management task. SPHINX attained a speaker-independent word accuracy of 96% with a grammar (perplexity 60), and 82% without grammar (perplexity 997).
Animated free-form deformation: an interactive animation technique
Authors: Sabine Coquillart, Pierre Jancéne
Venue: ACM SIGGRAPH Computer Graphics (1991)

Current research efforts focus on providing interactive techniques that make 3D concepts easy to use and accessible to large numbers of people. In this paper, a new interactive technique for animating deformable objects is presented. The technique allows easy specification and control of a class of deformations that cannot be produced by existing techniques without considerable human intervention.The methodology proposed relies on the Free-Form Deformation (FFD) technique. It makes use of a deformation tool that is animated like any other object.This approach provides a representation of the deformations independent of the surface geometry, and can be easily integrated into traditional hierarchical animation systems.
Building Flexible Real-Time Systems Using the Flex Language
Authors: Kevin B. Kenny, Kwei-Jay Lin
Venue: Computer (1991)

The design and implementation of a real-time programming language called Flex, which is a derivative of C++, are presented. It is shown how different types of timing requirements might be expressed and enforced in Flex, how they might be fulfilled in a flexible way using different program models, and how the programming environment can help in making binding and scheduling decisions. The timing constraint primitives in Flex are easy to use yet powerful enough to define both independent and relative timing constraints. Program models like imprecise computation and performance polymorphism can carry out flexible real-time programs. In addition, programmers can use a performance measurement tool that produces statistically correct timing models to predict the expected execution time of a program and to help make binding decisions. A real-time programming environment is also presented.
Volumetric shape description of range data using &ldquo;Blobby Model&rdquo;
Authors: Shigeru Muraki
Venue: ACM SIGGRAPH Computer Graphics (1991)

Recently in the field of computer vision, there have been many attempts to obtain a symbolic shape description of an object by fitting simple primitives to the range data of the object. In this paper, we introduce the "Blobby Model" for automatically generating a shape description from range data. This model can express a 3D surface as an isosurface of a scalar field which is produced by a number of field generating primitives. The fields from many primitives are blended with each other and can form a very complicated shape. To determine the number and distribution of primitives required to adequately represent a complex 3D surface, an energy function is minimized which measures the shape difference between the range data and the "Blobby Model". We start with a single primitive and introduce more primitives by splitting each primitive into two further primitives so as to reduce the energy value. In this manner, the shape of the 3D object is slowly recovered as the isosurface produced by many primitives. We have successfully applied this method to human face range data and typical results are shown. The method herein does not require any prior range segmentation.
A comprehensive physical model for light reflection
Authors: Xiao D. He, Kenneth E. Torrance, François X. Sillion, Donald P. Greenberg
Venue: ACM SIGGRAPH Computer Graphics (1991)

A new general reflectance model for computer graphics is presented. The model is based on physical optics and describes specular, directional diffuse, and uniform diffuse reflection by a surface. The reflected light pattern depends on wavelength, incidence angle, two surface roughness parameters, and surface refractive index. The formulation is self consistent in terms of polarization, surface roughness, masking/shadowing, and energy. The model applies to a wide range of materials and surface finishes and provides a smooth transition from diffuse-like to specular reflection as the wavelength and incidence angle are increased or the surface roughness is decreased. The model is analytic and suitable for Computer Graphics applications. Predicted reflectance distributions compare favorably with experiment. The model is applied to metallic, nonmetallic, and plastic materials, with smooth and rough surfaces.
A seminar course in object oriented programming
Authors: David Bellin
Venue: Proceedings of the twenty-third SIGCSE technical symposium on Computer science education (1992)

The emerging technology of object oriented programming is just beginning to be introduced into the computer science curriculum. In most schools, it will be introduced first at the more advanced levels, prior to inclusion in introductory courses, even though the object oriented paradigm may be more suitable for teaching basic computer science concepts. This paper contains the experiences gained teaching a seminar on object oriented programming to a small group of mixed graduate and undergraduate students at a school with no doctoral program. The successes and difficulties faced by both students and instructor are explored.
On the Optimal Total Processing Time Using Checkpoints
Authors: Boyan Dimitrov, Zohel Khalil, Nikolay Kolev, Peter Petrov
Venue: IEEE Transactions on Software Engineering (1991)

The authors investigate the problem of optimizing the expected blocking time duration by providing a schedule of checkpoints during the required job processing time. They give a general approach for determining the optimal checkpoint schedule and derive some cases when the optimal checkpointing is uniform. The model has applications in unreliable computing systems, multiclient computer service, data transmissions, etc.
Toward a lexicon of musical APL2 phrases (invited)
Authors: Stanley Jordan, Erik S. Frils
Venue: ACM SIGAPL APL Quote Quad (1991)

Both the programming environment and the notation of APL2 have proven useful in music theory and computer music. APL2 expressions can generate, test, and modify data structures representing musical syntax (actual passages or songs) or musical semantics (facts, ideas, or relationships in music). In this paper our primary concern is syntax-oriented. We examine a few basic parameters of music, introduce data structures that capture essential features of these parameters, and explore some useful expressions. Within these expressions we find several typical "musical objects" and some common transformations on these objects. Most of the expressions are simple, but their musical results are far from trivial. This only underscores the power of APL2.
Fast Homotopy-Preserving Skeletons Using Mathematical Morphology
Authors: Liang Ji, Jim Piper
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (1992)

Two algorithms for skeletonization of 2-D binary images, each of which explicitly separates the two major aspects of skeletonization are described: the identification of points critical to shape representation, and the identification of further points necessary to preserve homotopy. Sets of points critical to shape representation are found by eroding the original image I with a nested sequence of structuring elements E/sub i/. By choosing appropriate (E/sub i/) and D, a structuring element, either algorithm is capable of producing a variety of skeletons corresponding to different distance functions. A sufficient condition is given for the original image to be reconstructed from the skeleton. In the case of the first algorithm, there are few restrictions on the set of structuring elements. It uses a simple search strategy to find points whose removal would alter homotopy. The second, faster, algorithm has a more constructional approach to finding points necessary for preserving homotopy, which limits it to a more restricted set of structuring elements than the first algorithm. However, it may still be used with a variety of distance functions.
Surface Shape Reconstruction of a Nonrigid Transport Object Using Refraction and Motion
Authors: Hiroshi Murase
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (1992)

The appearance of a pattern behind a transparent, moving object is distorted by refraction at the moving object's surface. An algorithm for reconstructing the surface shape of a nonrigid transparent object, such as water, from the apparent motion of the observed pattern is described. This algorithm is based on the optical and statistical analysis of the distortions. It consists of four steps: extraction of optical flow, averaging of each point trajectory obtained from the optical flow sequence, calculation of the surface normal using optical characteristics, and reconstruction of the surface. The algorithm is applied to both synthetic and real images to demonstrate its performance.
A framework for high level synthesis of digital architectures from u-recursive algorithms
Authors: Khaled M. Elleithy, Magdy A. Bayoumi
Venue: Proceedings of the 1990 ACM annual conference on Cooperation (1990)

The major drawback of reported high level synthesis techniques is their limited applicability to a specific class of algorithms without extendibility to general algorithms and the lack of a formal approach to prove the correctness of the such techniques. In this paper, we introduce a novel approach for high level synthesis from &mgr;-recursive algorithms. Two features are provided by the approach: completeness and correctness. Completeness means the ability to use the approach for any general algorithm. Correctness is achieved by using a set of transformations that are proved to be correct. A formal framework for the synthesis procedure has been developed which can be easily automated. A given algorithm will be represented in a new developed language termed Algorithm Specification Language (ASL). ASL has the ability to describe any general algorithm. An automatic procedure is used to transform an ASL representation into a specific realization specification using a correctness preserving set of transformations. The realization format is based on representing the digital architectures by a Realization Specification Language(RSL).
Algernon&mdash;a tractable system for knowledge-representation
Authors: J. M. Crawford, B. J. Kuipers
Venue: ACM SIGART Bulletin (1991)

Access-Limited Logic (ALL) is a theory of knowledge representation which formalizes the access limitations inherent in a network structured knowledge-base. Where a deductive method such as resolution would retrieve all assertions that satisfy a given pattern, an access-limited logic retrieves only those assertions reachable by following an available access path. The time complexity of inference in ALL is a polynomial function of the size of the accessible portion of the knowledge-base, rather than an exponential function of the size of the entire knowledge-base (as in much past work). Access-Limited Logic, though incomplete, still has a well defined semantics and a weakened form of completeness, Socratic Completeness, which guarantees that for any fact which is a logical consequence of the knowledge-base, there is a series of preliminary queries and assumptions after which a query of the fact will succeed.
Using explanation-based learning to increase performance in a large-scale NL query system
Authors: Manny Rayner, Christer Samuelsson
Venue: Proceedings of the workshop on Speech and Natural Language (1990)

Explanation-based learning (EBL) is a machine-learning technique, closely connected to other techniques like macro-operator learning, chunking, and partial evaluation; a phrase we have found useful for describing the method to logic programmers is <i>example-guided partial evaluation.</i> The basic ideas of the method are well-described in an overview article which recently appeared in <i>Artificial Intelligence</i> [1], to which we refer the reader who wants to understand the theoretical principles; here, we will only summarize briefly what EBL means in the context of natural-language processing. A detailed presentation can be found in [3] and [4].
On integer-to-rational conversion algorithm
Authors: T. Sasaki, M. Sasaki
Venue: ACM SIGSAM Bulletin (1992)

Let m be a positive integer. Given an integer u, there exists at most one rational number a/b, gcd(a, b) = 1 and b ge; 1, such that u equiv; a/b (mod m), 1 le; b lt; radic;m/2 and |a| lt; radic;m/2. Wang [1] presented an algorithm for calculating a and b for given integers m and u, with insufficient proof of the algorithm. Wang-Guy-Davenport [2] gave a proof of the algorithm, using a theorem in number theory, but the authors cannot understand the proof. This short article gives an elementary proof of Wang's algorithm.
A rewrite-based type discipline for a subset of computer algebra
Authors: H. Comon, D. Lugiez, Ph. Schnoebelen
Venue: Journal of Symbolic Computation (1991)

This paper is concerned with the type structure of a system including polymorphism, type properties and subtypes. This type system originates from computer algebra but it is not intended to be the solution of all type problems in this area. Types (or sets of types) are denoted by terms in some order-sorted algebra. @? We consider a rewrite relation in this algebra, which is intended to express subtyping. The relations between the semantics and the axiomatization are investigated. It is shown that the problem of type inference is undecidable but a narrowing strategy for semi-decision procedures is described and studied.
Enhanced Hypercubes
Authors: Nian-Feng Tzeng, Sizheng Wei
Venue: IEEE Transactions on Computers (1991)

A hypercube with extra connections added between pairs of nodes through otherwise unused links is investigated. The extra connections are made in a way that maximizes the improvement of the performance measure of interest under various traffic distributions. The resulting hypercube, called the enhanced hypercube, requires a simple routing algorithm and is guaranteed not to create any traffic-congested points or links. The enhanced hypercube achieves noticeable improvement in diameter, mean internode distance, and traffic density, and it also is more cost effective than a regular hypercube. An efficient broadcast algorithm that can considerably speed up the broadcast process in enhanced hypercubes is provided.
UC: a language for the connection machine
Authors: R. Bagrodia, K. M. Chandy, E. Kwan
Venue: Proceedings of the 1990 ACM/IEEE conference on Supercomputing (1990)

In designing parallel languages, the concern for defining a simple virtual machine must be balanced against the need to efficiently map a program on a specific architecture. UC addresses this problem by separating the programming task from efficiency considerations. UC programs are designed using a small set of constructs that include reduction, parallel assignment and fixed-point computation. The language also provides a map section that may optionally be used by a programmer to specify data mappings for the program. This paper describes the UC constructs and their current implementation on the Connection Machine. It also presents measurements of the compiler for simple benchmarks.
Recent progress in robust vocabulary-independent speech recognition
Authors: Hsiao-Wuen Hon, Kai-Fu Lee
Venue: Proceedings of the workshop on Speech and Natural Language (1991)

This paper reports recent efforts to improve the performance of CMU's robust vocabulary-independent (VI) speech recognition systems on the DARPA speaker-independent resource management task. The improvements are evaluated on 320 sentences that randomly selected from the DARPA June 88, February 89 and October 89 test sets. Our first improvement involves more detailed acoustic modeling. We incorporated more dynamic features computed from the LPC cepstra and reduced error by 15% over the baseline system. Our second improvement comes from a larger training database. With more training data, our third improvement comes from a more detailed subword modeling. We incorporated the word boundary context into our VI subword modeling and it resulted in a 30% error reduction. Finally, we used decision-tree allophone clustering to find more suitable models for the subword units not covered in the training set and further reduced error by 17%. All the techniques combined reduced the VI error rate on the resource management task from 11.1% to 5.4% (and from 15.4% to 7.4% when training and testing were under different recording environment). This vocabulary-independent performance has exceeded our vocabulary-dependent performance.
The implicit midpoint rule applied to discontinuous differential equations
Authors: Alois E. Kastner-Maresch
Venue: Computing (1993)

The numerical solution of initial value problems with state-discontinuous right-hand sides by the implicit midpoint rule is discussed. The differential equations are transformed into differential inclusions following an approach of Filipov. An algorithm together with numerical tests is presented. &mdash;From the Abstract
A concurrent compiler for Modula-2+
Authors: David B. Wortman, Michael D. Junkin
Venue: Proceedings of the ACM SIGPLAN 1992 conference on Programming language design and implementation (1992)

In this paper we describe a collection of techniques for the design and implementation of concurrent compilers. We begin by describing a technique for dividing a source program into many streams so that each stream can be compiled concurrently. We discuss several compiler design issues unique to concurrent compilers including source program partitioning, symbol table management, compiler task scheduling and information flow constraints. The application of our techniques is illustrated by a complete design for a concurrent Modula-2+ compiler. After describing the structure of this compiler's performance that demonstrates that significant improvements in compilation time can be achieved through the use of concurrency.
Loop distribution with arbitrary control flow
Authors: Ken Kennedy, Kathryn S. McKinley
Venue: Proceedings of the 1990 ACM/IEEE conference on Supercomputing (1990)

Loop distribution is an integral part of transforming a sequential program into a parallel one. It is used extensively in parallelization, vectorization, and memory management. For loops with control flow, previous methods for loop distribution have significant drawbacks. We present a new algorithm for loop distribution in the presence of control flow modeled by a control dependence graph. This algorithm is shown optimal in that it generates the minimum number of new arrays and tests possible. We also present a code generation algorithm that produces code for the resulting program without replicating statements or conditions. Although these algorithms are being developed for use in an interactive parallel programming environment for Fortran, they are very general and can be used in automatic parallelization and vectorization systems. Keywords: parallelization, vectorization, transformation, control dependence, data dependence, loop distribution
Performance analysis of concurrent-read exclusive-write
Authors: Martin Reiman, Paul E. Wright
Venue: ACM SIGMETRICS Performance Evaluation Review (1991)

We analyze the concurrent-read exclusive-write protocol for access to a shared resource, such as occurs in database and distributed operating systems. Readers arrive according to a Poisson process and acquire shareable i.e., non-exclusive, locks which, once granted, are released after a generally distributed random period. Writers arrive according to an arbitrary renewal process and acquire exclusive locks which, once granted, are held for a random time which is also generally distributed. Locks are granted in the order in which requests are received.We derive necessary and sufficient conditions under which the queue is stable i.e., the Iatencies for reader/writer lock acquisition have a limiting distribution. In the unstable case, the delays of successive readers/writers become unbounded. The stability condition is sensitive to the interarrival-time distribution of the writers and the lock holding-time distribution of the readers but depends only on the mean lock holding-time of the writers.Distributional and moment bounds are given for the latencies of read/write requests.
A vectorized long-period shift-register random number generator
Authors: Salvatore Filippone, Paolo Santangelo, Marcello Vitaletti
Venue: Proceedings of the 1990 ACM/IEEE conference on Supercomputing (1990)

A pseudo-random number generator, based on a linear-feedback shift-register sequence, is presented. The very long period of the generator, 21279 &mdash; 1, makes it useful in modern statistical simulations where the shorter period of other generators could either be exhausted during a single run or determine departures from uniform randomness when generating positions in a multidimensional space. In particular, the proposed generator overcomes the limitations of multiplicative-congruential generators with modulus 231 &mdash; 1, which are widely used on computers with a 32-bit integer word size, such as the IBM S/370 family of computers.
The on-line d-dimensional dictionary problem
Authors: Teofilo F. Gonzalez
Venue: Proceedings of the third annual ACM-SIAM symposium on Discrete algorithms (1992)

We present a new algorithm for the on-line d-dimensional dictionary problem which has many applications including the management of geometrical objects and geometrical searching. The dictionary problem consists of executing on-line any sequence of the following operations: INSERT(p), DELETE(p) and MEMBERSHIP(p), where p is any point in d-space. We introduce a clean structure based on balanced binary search trees, which we call d-dimensional balanced binary search trees, to represent the set of points. We present algorithms for each of the above operations that take O(d + log n) time, where n is the current number of points in the set, and each INSERT and DELETE operation requires no more than a constant number of rotations. Our procedures are almost identical to the ones for balanced binary search trees. The main difference is in the way we search for an element. Our search strategy is based on the principle &ldquo;assume, verify and conquer&rdquo; (AVC). We apply this principle as follows. To avoid multiple verifications we shall assume that some prefixes of strings match. At the end of our search we must determine whether or not these assumptions were valid. This can be done by performing one simple verification step that takes O(d) time. The elimination of multiple verifications is important because in the worst case there are &OHgr;(log n) verifications, and each could take &OHgr;(d) time.
On subsumption and semiunification in feature algebras
Authors: Jochen Dörre, William C. Rounds
Venue: Journal of Symbolic Computation (1992)

We consider a generalization of term subsumption, or matching, to a class of mathematical structures which we call feature algebras. We show how these generalize both first-order terms and the feature structures used in computational linguistics. The notion of term subsumption generalizes to a natural notion of algebra homomorphism. In the setting of feature algebras, unification, corresponds naturally to solving constraints involving equalities between strings of unary function symbols, and semiunification also allows inequalities representing subsumption constraints. Our generalization allows us to show that the semiunification problem for finite feature algebras is undecidable. This implies that the corresponding problem for rational trees (cyclic terms) is also undecidable.