ppxscal/embedding_network huggingface dataset:
Bulk types: built-in or add-on?
Authors: Florian Matthes, Joachim W. Schmidt
Venue: Proceedings of the third international workshop on Database programming languages : bulk types persistent data: bulk types persistent data (1992)

Bulk structures play a central r&ocirc;le in data-intensive application programming. The issues of bulk type definition and implementation as well as their integration into database programming languages are, therefore, key topics in current DBPL research. In this paper we raise a more general language design and implementation issue by asking whether there should be at all built-in bulk types in DBPLs. Instead, one could argue that bulk types should be realized exclusively as user-definable add-ons to unbiased core languages with appropriate primitives and abstraction facilities. In searching for an answer we first distinguish two substantially different levels on which bulk types are supported. Elementary Bulk essentially copes with persistent storage of mass data, their identification and update. Advanced Bulk provides additional support required for data-intensive applications such as optimized associatve queries and integrity support under concurrency and failure. Our long-term experience with bulk types in the DBPL language and system clearly shows the limitation of the built-in approach: built-in Advanced Bulk, as elaborate as it may be, frequently does not cover the whose range of demands of a fully-fledged application and often does not provide a decent pay-off for its implementation effort. On the other hand, restriction to built-in Elementary Bulk gives too little user-support for most data-intensive applications. We report our current work on open database application systems which favours DBPLs with bulk types as add-ons, and outline some of the technological requirements for highly reusable implementations of languages with advanced user-provided bulk type definitions.
Asynchronous and stand-alone entries
Authors: Richard Powers
Venue: ACM SIGAda Ada Letters (1990)

This report summarizes the discussions held on asynchronous and stand-alone entries.
Prototyping an instructible interface: Moctec
Authors: David L. Maulsby
Venue: Proceedings of the SIGCHI conference on Human factors in computing systems (1992)

Moctec is a set of interactive mockups of an interface for programming search and replace tasks by example. The user guides inference by pointing at relevant features of data.
On p-adic computation of the rational form of a matrix
Authors: Marie-Hélène Mathieu, David Ford
Venue: Journal of Symbolic Computation (1990)

We consider the problem of bringing a given matrix into ''cyclic form,'' from which the rational form can be computed easily. Matrices are taken to have p-adic integer entries, and computations are done with rational integer approximations to p-adic integers. We give bounds on the precision necessary to ensure that the resulting cyclic form is indeed similar to the original matrix. We also give a criterion for deciding whether the cyclic form is correct.
Subcube Allocation in Hypercube Computers
Authors: Shantanu Dutt, John P. Hayes
Venue: IEEE Transactions on Computers (1991)

A precise characterization of the subcube allocation problem and a general methodology to solve it are presented. Subcube allocation and coalescing algorithms that have the goal of minimizing fragmentation are developed. The concept of a maximal set of subcubes (MSS), which is useful in making allocations that result in a tightly packed hypercube, is introduced. The problems of allocating subcubes and of forming an MSS are formulated as decision problems and shown to be NP-hard. It is proved analytically that the buddy strategy is optimal under restricted conditions, and it is shown using simulation that its performance is actually poor under more realistic conditions. A heuristic procedure for efficiently coalescing a released cube with the existing free cubes is suggested. This coalescing approach is coupled with a simple best-fit allocation scheme to form the basis of a class of MSS-based strategies that give a substantial performance (hit ratio) improvement over the buddy strategy. Simulation results comparing several different allocation and coalescing strategies, which show that the MSS-based schemes provide a marked performance improvement over previous techniques, are presented.
An Efficient Deadlock Avoidance Technique
Authors: Ferenc Belik
Venue: IEEE Transactions on Computers (1990)

A deadlock avoidance technique, based on a method of representing directed acyclic graphs, is presented. This technique is suitable for systems with single resources of each resource type. The deadlock avoidance problem considered is the problem of changing a directed acyclic graph while keeping it acyclic. The resource allocation algorithm involves three operations on edges corresponding to release of a resource from a process, unsuccessful allocation of a resource to a process, and successful allocation of a resource to a process, where the allocations include a previous detection of cycles. A path matrix representation is used, making it possible to detect cycles efficiently. The low cost of cycle detection can amortize the cost of the other operations and linear (or even constant) amortized time for one operation can be attained in dense systems.
Topics in teaching and using APL2
Authors: Norman Thomson
Venue: ACM SIGAPL APL Quote Quad (1990)

APL2 is like many subjects in programming and mathematics in that it can appear sprawling, complex, vast and difficult to grasp if a few underlying principles are not well understood. Selecting and emphasising these to the point where they become the basis of ingrained habits on the part of students is the first crucial step towards success in teaching APL2. The next is to use these principles to separate clearly the roles of a set of primitive functions, namely disclose, first, take, pick and index which have strong similarities both in their function and in the symbols used to represent them. Then comes the discipline of using these and other functions in ways that exploit the self-specification nature of APL2, which if applied properly bears the same relation to software engineering as alternative medicine does to the orthodox brand.
Algorithm 690: Chebyshev polynomial software for elliptic-parabolic systems of PDEs
Authors: M. Berzins, P. M. Dew
Venue: ACM Transactions on Mathematical Software (TOMS) (1991)

PDECHEB is a FORTRAN 77 software package that semidiscretizes a wide range of time-dependent partial differential equations in one space variable. The software implements a family of spacial discretization formulas, based on piecewise Chebyshev polynomial expansions with C0 continuity. The package has been designed to be used in conjunction with a general integrator for initial value problems to provide a powerful software tool for the solution of parabolic-elliptic PDEs with coupled differential algebraic equations. Examples are provided to illustrate the use of the package with the DASSL d.a.e integrator of Petzold [18].
A syntactic approach to fixed point computation on finite domains
Authors: Tyng-Ruey Chuang, Benjamin Goldberg
Venue: ACM SIGPLAN Lisp Pointers (1992)

We propose a syntactic approach to performing fixed point computation on finite domains. Finding fixed points in finite domains for monotonic fuctions is an essential task when calculating abstract semantics of functional programs. Previous methods for fixed point finding have been mainly based on semantic approaches which may be very inefficient even for simple programs. We outline the development of a syntactic approach, and show that the syntactic approach is sound and complete with respect to semantics. A few examples are provided to illustrate this syntactic approach.
How many operation units are adequate?
Authors: Wolfgang Matthes
Venue: ACM SIGARCH Computer Architecture News (1991)

A uniprocessor superscalar architecture is proposed which comprises four universal operation units arranged according to a tree-shaped dataflow graph, instruction issuing hardware, and oper and selection means. The control principles are based on VLIW, microprogramming, and dataflow concepts. The proposal emerged mainly from investigations of inherent mathematical structures of application problems, especially from the analysis of dataflow graphs of elementary mathematical fromulas (arithmetic of intervals, complex and rational numbers etc.). The particular operation unit itself is an ensemble of high-performance processing resources which may be compared to state-of-the-art processors (e. g. 1860). It may require a silicon budget from one to five million transistors. The whole processor may require 10 to 50 million transistors, thus being a suitable implementation target for IC technologies of the 90's.
Group HCI design: problems and prospects
Authors: Bernard J. Catterall, Susan Harker, Gary Klein, Mark Notess, John C. Tang
Venue: ACM SIGCHI Bulletin (1990)

Design of human-computer interfaces is typically carried out by groups of designers rather than by isolated individuals. In this report, we characterize those groups and their contexts, examine the problems that such groups encounter, and evaluate the extent to which current HCI techniques address the needs of groups of designers.
Numerical comparisons of some explicit Runge-Kutta pairs of orders 4 through 8
Authors: P. W. Sharp
Venue: ACM Transactions on Mathematical Software (TOMS) (1991)

We performed numerical testing of six explicit Runge-Kutta pairs ranging in order from a (3,4) pair to a (7,8) pair. All the test problems had smooth solutions and we assumed dense output was not required. The pairs were implemented in a uniform way. In particular, the stepsize selection for all pairs was based on the locally optimal formula. We tested the efficiency of the pairs, to what extent tolerance proportionality held, the accuracy of the local error estimate and stepsize prediction, and the performance on mildly stiff problems. We also showed, for these pairs, how the performance could be altered noticeably by making simple changes to the stepsize selection strategy. As part of the work, we demonstrated new ways of presenting numerical comparisons. &mdash;From the Author's Abstract
Datapath generator based on gate-level symbolic layout
Authors: Nobu Matsumoto, Yoko Watanabe, Kimiyoshi Usami, Yukio Sugeno, Hiroshi Hatada, Shojiro Mori
Venue: Proceedings of the 27th ACM/IEEE Design Automation Conference (1991)

This paper describes a new datapath generator that generates high-density mask layouts equivalent to hand-crafted ones. An entry of the generator is a hierarchical symbolic layout at the gate level. Bit-and-row-slicing technique is a key feature to realize large-size and high-density datapath generation. A 21K transistor datapath was generated using 1-&mgr;m CMOS technology, whose density is 5.64 KTr/mm2, greater than the 5.38 KTr/mm2 of a hand-crafted datapath.
DARPA resource management benchmark test results June 1990
Authors: D. S. Pallett, J. G. Fiscus, J. S. Garofolo
Venue: Proceedings of the workshop on Speech and Natural Language (1990)

The June 1990 DARPA Resource Management Benchmark Test makes use of the first of several test sets provided with the Extended Resource Management Speaker-Dependent Corpus (RM2) [1]. The corpus was designed as a speaker-dependent extension to the Resource Management (RM1) Corpus [2], consisting of (only) four speakers, but with a large number (2400) of sentence utterances for each of these speakers for system training purposes. The corpus was produced on CDROM by NIST in April 1990, and distributed to DARPA contractors. Results have been reported to NIST for both speaker-dependent and speaker-independent systems, and the results of NIST scoring and preliminary analysis of these data are included in this paper. In addition to the June 1990 (RM2) test set results, some sites also reported the results of tests of new algorithms on test sets that have been used in previous results ("test-retest" results), or for new (first-time) use of previous test sets, or for new systems in development. Those results are also tabulated.
Empirical measurements of six allocation-intensive C programs
Authors: Benjamin Zorn, Dirk Grunwald
Venue: ACM SIGPLAN Notices (1992)

Dynamic memory management is an important part of a large class of computer programs and high-performance algorithms for dynamic memory management have been, and will continue to be, of considerable interest. This paper presents empirical data from a collection of six allocation-intensive C programs. Extensive statistics about the allocation behavior of the programs measured, including the distributions of object sizes, lifetimes, and interarrival times, are presented. This data is valuable for the following reasons: first, the data from these programs can be used to design high-performance algorithms for dynamic memory management. Second, these programs can be used as a benchmark test suite for evaluating and comparing the performance of different dynamic memory management algorithms. Finally, the data presented gives readers greater insight into the storage allocation patterns of a broad range of programs. The data presented in this paper is an abbreviated version of more extensive statistics that are publically available on the internet.
Watersheds in Digital Spaces: An Efficient Algorithm Based on Immersion Simulations
Authors: Luc Vincent, Pierre Soille
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (1991)

A fast and flexible algorithm for computing watersheds in digital gray-scale images is introduced. A review of watersheds and related motion is first presented, and the major methods to determine watersheds are discussed. The algorithm is based on an immersion process analogy, in which the flooding of the water in the picture is efficiently simulated using of queue of pixel. It is described in detail provided in a pseudo C language. The accuracy of this algorithm is proven to be superior to that of the existing implementations, and it is shown that its adaptation to any kind of digital grid and its generalization to n-dimensional images (and even to graphs) are straightforward. The algorithm is reported to be faster than any other watershed algorithm. Applications of this algorithm with regard to picture segmentation are presented for magnetic resonance (MR) imagery and for digital elevation models. An example of 3-D watershed is also provided.
Automatic discovery of contextual factors describing phonological variation
Authors: Francine Chen, Jeff Shrager
Venue: Proceedings of the workshop on Speech and Natural Language (1989)

In this paper we describe a method for automatically discovering subsets of contextual factors which, taken together, are useful for predicting the <i>realizations</i>, or pronunciations, of English words for continuous speech recognition. A decision tree is used for organizing contextual descriptions of phonological variation. This representation enables us to categorize different realizations according to the context in which they appear in the corpus. In addition, this organization permits us to consider simplifications such as pruning and branch clustering, leading to parsimonious descriptions that better predict allophones in these contexts. We created trees to examine the working assumption that preceding phoneme and following phoneme provide important contexts, as exemplified by the use of triphones in hidden Markov models; our results were in general accordance with the assumption. However, we found that other contexts also play a significant role in phoneme realizations.
Synthesis using path-based scheduling: algorithms and exercises
Authors: Raul Compasano, Reinaldo A. Bergamaschi
Venue: Proceedings of the 27th ACM/IEEE Design Automation Conference (1991)

Path-based scheduling algorithms consider all possible sequences of operations (called paths) in a control-flow graph. Unlike most scheduling techniques used in high-level synthesis, they stress optimization across conditional branches. This paper presents several path-based algorithms. An exact algorithm finds the minimum number of control steps required for each possible path being executed. Heuristic solutions were also implemented. Extensive application of these algorithms to the benchmarks of the High-Level Synthesis Workshop showed the practical feasibility of such methods.
Multiprocessor real-time threads
Authors: Karsten Schwan, Hongyi Zhou
Venue: ACM SIGOPS Operating Systems Review (1992)

Portability is an important attribute of real-time operating systems because their target hardware environments routinely vary from special purpose processors to parallel machines to distributed execution environments. In this paper, we address the issue of operating systems portability by development of a real-time threads package based on the Mach cthreads interface. Real-time threads have been implemented on standard Unix platforms and on a 32-node BBN Butterfly multiprocessor. In contrast to cthreads, the schedulability of real-time threads may be determined dynamically at the time of threads creation. In addition, any scheduling guarantees made at thread creation time are maintained when threads communicate or cooperate using the package's other primitives.
The BBN BYBLOS Continuous Speech Recognition system
Authors: Richard Schwartz, Chris Barry, Yen-Lu Chow, Alan Derr, Ming-Whei Feng, Owen Kimball, Francis Kubala, John Makhoul, Jeffrey Vandegrift
Venue: Proceedings of the workshop on Speech and Natural Language (1989)

In this paper we describe the algorithms used in the BBN BYBLOS Continuous Speech Recognition system. The BYBLOS system uses context-dependent hidden Markov models of phonemes to provide a robust model of phonetic coarticulation. We provide an update of the ongoing research aimed at improving the recognition accuracy. In the first experiment we confirm the large improvement in accuracy that can be derived by using spectral derivative parameters in the recognition. In particular, the word error rate is reduced by a factor of two. Currently the system achieves a word error rate of 2.9% when tested on the speaker-dependent part of the standard 1000-Word DARPA Resource Management Database using the Word-Pair grammar supplied with the database. When no grammar was used, the error rate is 15.3%. Finally, we present a method for smoothing the discrete densities on the states of the HMM, which is intended to alleviate the problem of insufficient training for detailed phonetic models.
A Reinforcement Connectionist Approach to Robot Path Finding in Non-Maze-Like Environments
Authors: José Del R. Millán, Carme Torras
Venue: Machine Learning (1992)

This paper presents a reinforcement connectionist system which finds and learns the suitable situation-action rules so as to generate feasible paths for a point robot in a 2D environment with circular obstacles. The basic reinforcement algorithm is extended with a strategy for discovering stable solution paths. Equipped with this strategy and a powerful codification scheme, the path-finder (i) learns quickly, (ii) deals with continuous-valued inputs and outputs, (iii) exhibits good noise-tolerance and generalization capabilities, (iv) copes with dynamic environments, and (v) solves an instance of the path finding problem with strong performance demands.
Edison, a Unix and C friendly Rete based production system
Authors: Bernard Thirion
Venue: ACM SIGPLAN Notices (1992)

This document introduces the architecture and the implementation of a rule based system especially devised to be integrated in the C and UNIX world. Built around the Edison knowledge description language and its translator, the environment features an inference engine using the Rete algorithm as well as a trace mechanism and a debugger. The who set can be used in full autonomy to design an expert system, or it can be integrated into a wider application as a software component. We shall describe the Edison language, its translation, the development environment and the performances of our production system.
Predictable real-time avionics design using Ada tasks and Rendezvous study
Authors: C. D. Locke, D. R. Vogel, T. J. Mesler
Venue: ACM SIGAda Ada Letters (1990)

As a part of the Software Engineering Institute's Real-Time Software in Ada project, personnel from IBM, the Naval Weapons Center, and SEI carried out an effort to construct a realistic hard real-time avionics application using Ada, including Ada tasking and rendezvous. In this joint study, an important goal was to determine how to use the Ada language as it was designed to be used in a hard real-time system, rather than continuing the current practice of avoiding the very constructs Ada's designers created to meet real-time requirements. In this paper, we present the avionics problem considered, as well as a high-level overview of an Ada solution to the problem which uses Ada tasking and rendezvous, resulting in a solution fully capable of predictably meeting its time constraints.
Ham-sandwich cuts in Rd
Authors: Jiří Matoušek, Chi-Yuan Lo, William Steiger
Venue: Proceedings of the twenty-fourth annual ACM symposium on Theory of computing (1992)

Lo and Steiger resolved the complexity question for computing a planar ham-sandwich cut by giving an optimal linear-time algorithm. We show how to generalize the ideas to every fixed dimension d > 2 by describing an algorithm that computes a ham-sandwich cut in Rd in time O(nd&ndash;1&ndash;a(d)), for some a(d) > 0 (going to zero as d increases). For d = 3,4, the running time is almost proportional to ed&ndash;1(n;n/2), where dd(k;n) denotes the maximal number of k-sets over sets of n points in Rd, and with the current best bounds, we get O(n3/2 log2 n/log n) running time for d = 3 and O(n8/3+&egr;) for d=4. We also give a linear time algorithm for three dimensional ham-sandwich cuts when the three sets are suitably separated.
Integrating human factors on a large scale: product usability champions
Authors: Deborah Mrazek, Michael Rafeld
Venue: Proceedings of the SIGCHI conference on Human factors in computing systems (1992)

This paper describes how a software development division in a large corporate environment found a creative way to integrate human factors techniques into their development processes. It discusses the limitations of a single Human Factors Engineer, the needs of a typical engineer on a software project, and how these limitations and needs produced the Product Usability Champion Program. Product Usability Champions are representatives from each software project in the division who act as usability watchdogs for their respective projects. The Human Factors Engineer's responsibility is to provide support to these Champions. This support includes access to a Usability Lab, technical advice, references, consulting, classroom training, hands-on training, Usability Champion program facilitation and support, and specific project team involvement. This paper describes the program's structure, implementation, and success.
Getting raster ellipses right
Authors: M. Douglas McIlroy
Venue: ACM Transactions on Graphics (TOG) (1992)

A concise, incremental algorithm for raster approximations to ellipses in standard position produces approximations that are good to the last pixel even near octant boundaries or the thin ends of highly eccentric ellipses. The resulting approximations commute with reflection about the diagonal and are mathematically specifiable without reference to details of the algorithm.
Distributed Ada: a suggested solution for Ada 9X
Authors: B. Dobbing
Venue: ACM SIGAda Ada Letters (1990)

This paper contains a suggested solution to the problems of implementing Ada in non-shared memory distributed systems for incorporation into Ada9X. The solution is based on three fundamental principles: firstly that there should be minimal disturbance to the existing Ada language definition; secondly that the security aspects of the language are not compromised; and thirdly that the requirements of implementors of distributed systems be met in full.