ppxscal/embedding_network huggingface dataset:
Student designed machines for a theory of computation course
Authors: Joan Krone
Venue: ACM SIGCSE Bulletin (1992)

Most Computer Science faculty members look forward to teaching a course in Theory of Computation. However, there is usually concern over how well students are able to understand Turing's thesis, Church's thesis, and the relationship between them with only one semester of concentration on details of a particular textbook. This paper describes how students in the Theory of Computation Course at Denison University designed their own theoretic machines and showed how those machines could be used to solve example problems, hopefully achieving an understanding of the theses by Church and Turing as a result of developing the technical details necessary in describing their machines.
Processing Poisson series in parallel
Authors: André Deprit, Etienne Deprit
Venue: Journal of Symbolic Computation (1990)

A massively parallel processor proves to be a powerful tool for manipulating large Poisson series. Assuming the series to be sparse, as in most problems of non-linear dynamics, they map into the computer one term per processor. The parallel processor then executes the basic operations in the free algebra of Poisson series over the field of real or rational numbers. We describe a prototype Poisson series processor currently running on the Connection Machine. Timing the calculation of various expansions in the two-body problem demonstrates massive parallelism's potential for tackling the enormous symbolic calculations customary in non-linear dynamics.
LispView: leverage through integration
Authors: Hans Muller
Venue: Communications of the ACM (1991)

Although Lisp was the host for many of the first graphical user interface (GUI) packages, popular activity in this area has shifted to more primitive but widely used languages such as C and C++. One explanation for this shift is that while Lisp's strength in rapid prototyping and development led to the initial progress, it also tended to inspire an imperialist attitude: applications were often crafted exclusively in Lisp, even when part of the application could make use of an existing conventional language library. We believe the ideal way to construct a CommonLisp GUI package today is to integrate proven C libraries with an object-oriented Lisp framework.
Transmission facilities for computer communications
Authors: A. G. Fraser, P. S. Henry
Venue: ACM SIGCOMM Computer Communication Review (1992)

This paper presents a brief introduction to architectures and technologies that probably will be used for wide-area communications. It starts with a review of the structure of today's network and some aspects of the digital transmission systems that dominate modem networks. Then the status and trends in wide-area transmission technology are addressed, first for the backbone network and then for the local access network. Local access refers to the transmission systems which connect customer premises to the nearestlocal exchange switch, and the backbone provides wide-area interconnection between local exchange switches.
Requirements Validation Through Viewpoint Resolution
Authors: Julio Cesar Sampaio do Prado Leite, Peter A. Freeman
Venue: IEEE Transactions on Software Engineering (1991)

A specific technique-viewpoint resolution-is proposed as a means of providing early validation of the requirements for a complex system, and some initial empirical evidence of the effectiveness of a semi-automated implementation of the technique is provided. The technique is based on the fact that software requirements can and should be elicited from different viewpoints, and that examination of the differences resulting from them can be used as a way of assisting in the early validation of requirements. A language for expressing views from different viewpoints and a set of analogy heuristics for performing a syntactically oriented analysis of views are proposed. This analysis of views is capable of differentiating between missing information and conflicting information, thus providing support for viewpoint resolution.
Analysis and Refinement of Software Test Data Adequacy Properties
Authors: Allen Parrish, Stuart H. Zweben
Venue: IEEE Transactions on Software Engineering (1991)

Test data adequacy criteria are standards that can be applied to decide if enough testing has been performed. Previous research in software testing has suggested 11 fundamental properties which reasonable criteria should satisfy if the criteria make use of the structure of the program being tested. It is shown that there are several dependencies among the 11 properties making them questionable as a set of fundamental properties, and that the statements of the properties can be generalized so that they can be appropriately analyzed with respect to criteria that do not necessarily make use of the program's structure. An analysis that shows the relationships among the properties with respect to different classes of criteria which utilize the program structure and the specification in different ways is discussed. It is shown how the properties differ under the two models in order to maintain consistency that the dependencies are largely a result of five very weak existential properties, and that by modifying three of the properties, these weaknesses can be eliminated. The result is a reduced set of seven properties, each of which is strong from a mathematical perspective.
Modelling Prolog control
Authors: Roberto Barbuti, Michael Codish, Roberto Giacobazzi, Giorgio Levi
Venue: Proceedings of the 19th ACM SIGPLAN-SIGACT symposium on Principles of programming languages (1992)

The goal of this paper is to construct a semantic basis for the abstract interpretaion of Prolog programs. Prolog is a well-known logic programming language which applies a depth-first search strategy in order to provide a practical approximation of Horn clause logic. While pure logic programming has clean fix-point, model-theoretic and operational semantics the situation for Prolog is different. Difficulties in capturing the declarative meaning of Prolog programs have led to various semantic definitions which attempt to encode the search strategy in different mathematical frameworks. However semantic based analyses of Prolog are typically achieved by abstracting the more simple but less precise declarative semantics of pure logic Programs. We propose instead to model Prolog control in a simple constraint logic language which is presented together with its declarative and operational semantics. This enables us to maintain the usual approach to declarative semantics of logic programs while capturing control aspects such as search strategy and selection rule.
Diagnosabilities of Hypercubes Under the Pessimistic One-Step Diagnosis Strategy
Authors: A. Kavianpour, K. H. Kim
Venue: IEEE Transactions on Computers (1991)

The capabilities of a system-diagnosis technique based on mutual testing are discussed. The technique is applied to hypercube computer systems. A one-step diagnosis of hypercubes that involves only one testing phase, in which processors test each other, is described. Two kinds of one-step diagnosis are presented: the precise one-step diagnosis and the pessimistic one-step diagnosis. Results indicate that the degree of diagnosability of the n-dimensional hypercube (for short, n-cube), where n
Palette segmentation indexing: the MetaMap process
Authors: Michael D. Doyle
Venue: ACM SIGBIO Newsletter (1992)

The MetaMap process is particularly suited for representing and linking spatial and textual information in the development of interactive applications which must access large databases of 2-D and 3-D raster images. This process has proven particularly effective for the development of multimedia educational programs for medical education, such as interactive atlases for the anatomical sciences. MetaMap processing allows a user to obtain descriptive information concerning a feature of a displayed image by point to the location of the feature. Conversely, the user may enter descriptive textual information, and the locations of the responsive features are indicated. The data processing and memory storage requirements are minimized by encoding information about the image as a pixel/voxel bit map, and a color map in which the addresses or indices of the color map are correlated with the addresses or pointers to strings of descriptive information. Each color map address corresponds to a predefined set of features and descriptive information about those features. Since the pixel/voxel bit map defines a color map address for each location on the image, suitable programming of the color map can insure proper correlation of descriptive information with corresponding locations on the image. The correlation between color map addresses and the descriptive information about the features is represented most compactly by arranging or sorting the entries in the color map so that there is a correspondence between each predefined feature and a continous range of color map addresses. Therefore, for a specified color map address, the corresponding set of features and their pointers can be found by comparing the specified color map address to the limits of the color map address ranges for the various features. This interface allows hypermedia-type linking of image features to relevant multimedia "objects" such as test, images, sounds, and animations. Computational efficiency is maximized so that effective multimedia systems can be developed on low-end microprocessor platforms such as Intel 8088 or 80286-based systems. The method and apparatus for implementing the MetaMap process is protected by U.S. Patent #4,847,604.
A static and dynamic workload characterization study of the San Diego Supercomputer center Cray X-MP
Authors: Joseph Pasquale, Barbara Bittel, Daniel Kraiman
Venue: ACM SIGMETRICS Performance Evaluation Review (1991)

The San Diego Supercomputer Center is one of four NSF sponsored national supercomputer centers. Up until January of 1990, its workhorse was a Cray X-MP, which served 2700 researchers from 170 institutions, spanning 44 states. In order to better understand how this supercomputer was utilized by its diverse community of users, we undertook a workload characterization study of the Cray X-MP. The goals of our study were twofold. First, we wished to characterize the workload at both the functional and resource levels. The functional level represents the user point of view: what types of programs users are running on the system. The resource level represents the system point of view: how the systems resources (CPU, memory, I/O bandwidth) are being used. Second, we wanted to see how the workload changed over an average weekday. Thus, we conducted a static characterization to understand its global attributes over the entire measurement period, as well as a dynamic workload characterization to understand the time behavior of the workload over a weekday cycle.
A &ldquo;pile&rdquo; metaphor for supporting casual organization of information
Authors: Richard Mander, Gitta Salomon, Yin Yin Wong
Venue: Proceedings of the SIGCHI conference on Human factors in computing systems (1992)

A user study was conducted to investigate how people deal with the flow of information in their workspaces. Subjects reported that, in an attempt to quickly and informally manage their information, they created piles of documents. Piles were seen as complementary to the folder filing system, which was used for more formal archiving. A new desktop interface element&ndash;the pile&ndash; was developed and prototyped through an iterative process. The design includes direct manipulation techniques and support for browsing, and goes beyond physical world functionality by providing system assistance for automatic pile construction and reorganization. Preliminary user tests indicate the design is promising and raise issues that will be addressed in future work.
Happy Birthday Mr. Babbage
Authors: Alfred W. Van Sinderen Michael R. Williams
Venue: IEEE Annals of the History of Computing (1991)

This birthday tribute to Charles Babbage incorporates a few extracts from his, and his friends', private letters in the hope of illuminating something of Babbage the man, rather than Babbage the scientist. The major portion of this tribute is a transcript of a 23 page letter (certainly one of the longest Babbage ever wrote) which, although it could be classified as a semi-formal document, is very illuminating as to the feelings and thought processes of Babbage in his later years.
An overview of three commercial object-oriented database management systems: ONTOS, ObjectStore, and O2
Authors: Valery Soloviev
Venue: ACM SIGMOD Record (1992)

We present an analysis of three current object-oriented DBMS products: ONTOS, ObjectStore, and O2, as described by their available documentation. The most attractive feature of ONTOS and Object-Store is their use of C++ as a user interface - a widespread object-oriented language. They also provide persistent data implementation, transaction and recovery mechanisms, and modern application development tool sets following the recommendations of [Atkinson et al. 89]. O2 was chosen for a well-developed data type system and end-user interface, and for its reputation from the literature.
Performance measures of the Ada Rendezvous
Authors: Anthony Sterrett, Marvin Minei
Venue: ACM SIGAda Ada Letters (1992)

The Ada Programming Language [ADA], was designed to meet the nee d for a standard computer programming language. Ada has the ability to take advantage of multiprocessor environments. One feature, known as th e rendezvous, allows tasks to synchronize in such a environment. In this paper, we will look at the performance of the Ada rendezvous in a two-processo r system.In a distributed Ada system, the rendezvous provides synchronize d communication between asynchronous tasks. A system of this sort woul d consist of at least two processors, each serving various tasks. Presently, th e performance behavior of tasks which synchronize and possibly communicat e are not widely known. Developers of concurrent Ada systems will need t o perform sensitivity studies of the Ada tasking environment to develo p efficient time-critical programs. Therefore, we will discuss Rendezvou s Response Time from the point of view of a sensitivity study. We will sho w generalized performance curves of the rendezvous along with commentary o n their performance elbows (or bottlenecks). Rendezvous Response Time will b e defined as the amount of time one task must wait until its rendezvous request t o another task is completed. The discussion will be based on two separat e computer simulations of a two-processor system. The tools to be used to build these simulations are [ELSIR] and [APOSL].
Closed-loop control with delayed information
Authors: Eitan Altman, Philippe Nain
Venue: Proceedings of the 1992 ACM SIGMETRICS joint international conference on Measurement and modeling of computer systems (1992)

The theory of Markov Control Model with Perfect State Information (MCM-PSI) requires that the current state of the system is known to the decision maker at decision instants. Otherwise, one speaks of Markov Control Model with Imperfect State Information (MCM-ISI). In this article, we introduce a new class of MCM-ISI, where the information on the state of the system is delayed. Such an information structure is encountered, for instance, in high-speed data networks. In the first part of this article, we show that by enlarging the state space so as to include the last known state as well as all the decisions made during the travel time of the information, we may reduce a MCM-ISI to a MCM-PSI. In the second part of this paper, this result is applied to a flow control problem. Considered is a discrete time queueing model with Bernoulli arrivals and geometric services, where the intensity of the arrival stream is controlled. At the beginning of slot t+1, t=0,1,2,&hellip;, the decision maker has to select the probability of having one arrival in the current time slot from the set {p1, p2}, 0 &le; p2 < p1 &le; 1, only on the basis of the queue-length and action histories in [0, t]. The aim is to optimize a discounted throughput/delay criterion. We show that there exists an optimal policy of a threshold type, where the threshold is seen to depend on the last action.
Bringing natural language information retrieval out of the closet
Authors: Donna Harman, Gerald Candela
Venue: ACM SIGCHI Bulletin (1990)

A prototype information retrieval system was developed that gives users fast and easy access to textual information. This system uses a statistical ranking methodology that allows a user to input a query using only natural language, such as a sentence or a noun phrase, with no special syntax required. The system returns a set of text titles or descriptions, ranked in order of likely relevance to the query. The user can then select one or more titles for further examination of the corresponding text. The prototype was tested by over forty users, all proficient in doing manual research in the subject area, but few proficient in doing online research. The system was very fast, providing response times on the order of one second for searching a gigabyte of data and was also very effective, retrieving at least one relevant record within the first ten records retrieved for 53 out of 68 test queries. All users were able to get satisfactory results within a short time after seeing a demonstration, and those that had never used an online retrieval system did as well as those with experience. This is in sharp contrast to Boolean based retrieval systems where continual use is necessary to obtain consistently good results.
The dragon continuous speech recognition system: a real-time implementation
Authors: Paul Bamberg, Yen-lu Chow, Laurence Gillick, Robert Roth, Dean Sturtevant
Venue: Proceedings of the workshop on Speech and Natural Language (1990)

We present a 1000-word continuous speech recognition (CSR) system that operates in real time on a personal computer (PC). The system, designed for large vocabulary natural language tasks, makes use of phonetic Hidden Markov models (HMM) and incorporates acoustic, phonetic, and linguistic sources of knowledge to achieve high recognition performance. We describe the various components of this system. We also present our strategy for achieving real time recognition on the PC. Using a 486-based PC with a 29K-based add-on board, the recognizer has been timed at 1.1 times real time.
A process-oriented scientific database model
Authors: J. Michael Pratt, Maxine Cohen
Venue: ACM SIGMOD Record (1992)

A database model is proposed for organizing data that describes natural processes studied experimentally. Adapting concepts from object-oriented and temporal databases, this process-oriented scientific database model (POSDBM) identifies two data object types (independent and dependent variables) and two types of relationships (becomes-a and affects-a) between data objects. Successive versions of dependent variable objects are associated by the becomes-a relationship, while independent and dependent variable objects are associated by the affects-a relationship. Thus, a process can be viewed as a sequence of states (versions) of a dependent variable object whose attributes are affected over time by independent variable objects.
LIVE: an architecture for learning from the environment
Authors: Wei-Min Shen
Venue: ACM SIGART Bulletin (1991)

This paper describes an integrated architecture called LIVE designed for learning from the environment. The task that LIVE faces is to solve problems in a new environment using its actions and senses. In order to be able to adapt to different environments, LIVE's actions and senses are defined as "innate" properties and their linkage (i.e., actions and their consequences) is unknown before entering a new environment. LIVE must coordinate a variety of intelligent activities in order to learn from the environment. These include problem solving, exploration, knowledge creation, knowledge revision, experimentation, and discovery. The paper gives an overview of the system and discusses its strengths and weaknesses along several dimensions in comparison with other similar architectures.
Computer simulation of high-speed impact response of composites
Authors: Scott Langlie, Wing Cheng, Ilhan Dilber
Venue: Proceedings of the 1990 ACM/IEEE conference on Supercomputing (1990)

This paper shares some of our experiences in the use of a supercomputer to facilitate the analysis and design of high velocity impact process in composite systems, and also in the benefits of color animation of the results on a MacIntosh computer. The calculations were carried out on a CRAY-2 using an impact model developed for high velocity impact/penetration of fiber-reinforced layered composites. The model is built on a continuum approach and includes a basic orthotropic constitutive material behavior. A computer program was developed to convert the results of the analysis for hundreds of time steps to 8-bit raster images and animated using graphics tools developed at NCSA. The same set of images were also directly recorded on a video tape.
Registration of Multiple Overlapping Range Images: Scenes Without Distinctive Features
Authors: Behrooz Kamgar-Parsi, Jeffrey L. Jones, Azriel Rosenfeld
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (1991)

A scheme is developed to register range images in an environment where distinctive features are scarce. Another issue addressed here is conflicting situations that may arise from pair-wise registration of multiple overlapping range images whether or not they contain distinctive features. There can be two causes for this: (a) error in individual registrations or (b) compression or bending in range images. The authors develop a scheme for resolving such conflicts for the case where range images share a common reference surface, i.e. when the transformation matrix between two overlapping images involves only three components: two translations and one rotation. The authors implemented this scheme to map the floor of the ocean, where the range data is obtained by a multibeam echo-sounder system installed aboard a sailing ship producing multiple overlapping range images. The system developed is the first automated system for correctly registered mapping of the ocean floor; it is efficient and robust.
Implementation and performance of Munin
Authors: John B. Carter, John K. Bennett, Willy Zwaenepoel
Venue: ACM SIGOPS Operating Systems Review (1991)

Munin is a distributed shared memory (DSM) system that allows shared memory parallel programs to be executed efficiently on distributed memory multiprocessors. Munin is unique among existing DSM systems in its use of multiple consistency protocols and in its use of release consistency. In Munin, shared program variables are annotated with their expected access pattern, and these annotations are then used by the runtime system to choose a consistency protocol best suited to that access pattern. Release consistency allows Munin to mask network latency and reduce the number of messages required to keep memory consistent. Munin's multiprotocol release consistency is implemented in software using a delayed update queue that buffers and merges pending outgoing writes. A sixteen-processor prototype of Munin is currently operational. We evaluate its implementation and describe the execution of two Munin programs that achieve performance within ten percent of message passing implementations of the same programs. Munin achieves this level of performance with only minor annotations to the shared memory programs.