ppxscal/embedding_network huggingface dataset:
An application of number theory to the organization of raster-graphics memory
Authors: Benny Chor, Charles E. Leiserson, Ronald L. Rivest, James B. Shearer
Venue: Journal of the ACM (JACM) (1986)

A high-resolution raster-graphics display is usually combined with processing power and a memory organization that facilitates basic graphics operations. For many applications, including interactive text processing, the ability to quickly move or copy small rectangles of pixels is essential. This paper proposes a novel organization of raster-graphics memory that permits all small rectangles to be moved efficiently. The memory organization is based on a doubly periodic assignment of pixels to M memory chips according to a &ldquo;Fibonacci&rdquo; lattice. The memory organization guarantees that, if a rectilinearly oriented rectangle contains fewer than M/ @@@@5 pixels, then all pixels will reside in different memory chips and thus can be accessed simultaneously. Moreover, any M consecutive pixels, arranged either horizontally or vertically, can be accessed simultaneously. We also define a continuous analog of the problem, which can be posed as: &ldquo;What is the maximum density of a set of points in the plane such that no two points are contained in the interior of a rectilinearly oriented rectangle of unit area?&rdquo; We show the existence of such a set with density 1/ @@@@5, and prove this is optimal by giving a matching upper bound.
UIO: a uniform I/O system interface for distributed systems
Authors: David R. Cheriton
Venue: ACM Transactions on Computer Systems (TOCS) (1987)

A uniform I/O interface allows programs to be written relatively independently of specific I/O services and yet work with a wide variety of the I/O services available in a distributed environment. Ideally, the interface provides this uniform access without excessive complexity in the interface or loss of performance. However, a uniform interface does not arise from careful design of individual system interfaces alone; it requires explicit definition. In this paper, the UIO (uniform I/O) system interface that has been used for the past five years in the V distributed operating system is described, with the focus on the key design issues. This interface provides several extensions beyond the I/O interface of UNIX&trade;, including support for record I/O, locking, atomic transactions, and replication, as well as attributes that indicate whether optional semantics and operations are available. Experience in using and implementing this interface with a variety of different I/O services is described, along with the performance of both local and network I/O. It is concluded that the UIO interface provides a uniform I/O system interface with significant functionality, wide applicability, and no significant performance penalty.
Programming for learning in mathematics and science
Authors: Sylvia A. Shafto
Venue: ACM SIGCSE Bulletin (1986)

This paper presents a learning-research based argument for the integration of computer programming into the science and mathematics curricula in pre-college education as well as college. Students who generate solutions to science and mathematics problems develop a procedural understanding of the fundamental theories of these disciplines. Students should be taught to use programming languages for these solutions for the same reasons they are taught the universal tools of arithmetic and algebra, and because only a computer provides the means to describe solutions in explicit, correct, and executable form. Programming should be integrated into all mathematics and science teaching from the earliest years. In precollege education, programming should be taught over a period of eight to ten years, rather than as a 6-12 week separate topic, and should be matched to the level of complexity of the science and mathematics content.
Time-Sensitive Cost Models in the Commercial MIS Environment
Authors: D. R. Jeffery
Venue: IEEE Transactions on Software Engineering (1987)

Current time-sensitive cost models suggest a significant impact on project effort if elapsed time compression or expansion is implemented. This paper reports an empirical study into the applicability of these models in the management information systems environment. It is found that elapsed time variation does not consistently affect project effort. This result is analyzed in terms of the theory supporting such a relationship, and an alternate relationship is suggested.
Discovering the secrets of DNA
Authors: Peter Friedland, Laurence H. Kedes
Venue: Communications of the ACM (1985)

Sophisticated software tools are becoming increasingly important in helping biologists understand how nature operates. Symbolic pattern-recognition and artificial-intelligence methodologies are contributing to the development of such software.
Entity-relationship diagrams and English: an analysis of some problems encountered in a database design course
Authors: Judith D. Wilson
Venue: ACM SIGCSE Bulletin (1987)

The simplicity and clarity of the entity-relationship approach recommends its use as a tool for teaching database design. Nonetheless, the approach does not appear to be problem-free. Analysis of student entity-relationship diagrams for two database design projects reveals a tendency students have to model English sentences and to use English syntax to guide the modeling process. The paper discusses why this may be the case, and how it may be avoided.
Ashley,K. D.-But, see, accord: generating blue book citations in HYPO
Authors: K. D. Ashley, E. L. Rissland
Venue: Proceedings of the 1st international conference on Artificial intelligence and law (1987)

An interesting and important aspect of legal reasoning is the use of citations to precedent cases as justifications for legal conclusions. In this paper, we describe the standard use of citations as described in the attorney's &ldquo;Blue Book&rdquo; and how HYPO, a program that models case-based legal reasoning, generates and uses citations in a very similar way to analyze fact situations and to communicate with an attorney/user. More specifically, we describe how, given a fact situation (&ldquo;cfs&rdquo;), HYPO dynamically generates the citations to cases in its Case Knowledge Base (&ldquo;CKB&rdquo;) by (1) analyzing the factual features of the cfs to see what dimensions apply, (2) retrieving and constructing a &ldquo;neighborhood&rdquo; of citable cases around the cfs (the &ldquo;Claim Lattice&rdquo;) and (3) constructing the &ldquo;Cites Display&rdquo;, a network of citations to the most on point cases (&ldquo;mopc&rdquo;) that is a skeletal frame for a legal argument about the cfs.
Some thoughts on the packet network architecture
Authors: Lixia Zhang
Venue: ACM SIGCOMM Computer Communication Review (1987)

Performance control in packet switching networks is one of the remaining areas that are yet to be explored. In this paper we look into the performance problems with two existing network architectures, datagram and virtual circuit. The major problem with the datagram network is lack of effective traffic control; and with the virtual circuit network, the improperly defined network control semantics and mechanisms. We consider that a new network architecture should be investigated in order to provide performance support for diverse applications.
Random and best-first document selection models
Authors: R. Losee
Venue: Proceedings of the 10th annual international ACM SIGIR conference on Research and development in information retrieval (1987)

Most document retrieval systems based on probabilistic models of feature distributions assume random selection of documents for retrieval. The assumptions of these models are met when documents are randomly selected from the database or when retrieving all available documents. A more suitable model for retrieval of a single document assumes that the best document available is to be retrieved first. Models of document retrieval systems assuming random selection and best-first selection are developed and compared under binary independence and two Poisson independence feature distribution models. Under the best-first model, feature discrimination varies with the number of documents in each relevance class in the database. A weight similar to the Inverse Document Frequency weight and consistent with the best-first model is suggested which does not depend on knowledge of the characteristics of relevant documents.
Comparison of analysis techniques for information requirement determination
Authors: Surya, B. Yadav, Ralph, R. Bravoco, Akemi, T. Chatfield, T. M. Rajkumar
Venue: Communications of the ACM (1988)

A comparison of systems analysis techniques, the Data Flow Diagram (DFD) and part of the Integrated Definition Method (IDEFo), is done using a new developmental framework.
The Kappa Network with Fault-Tolerant Destination Tag Algorithm
Authors: S. C. Kothari, G. M. Prabhu, Robert Roberts
Venue: IEEE Transactions on Computers (1988)

The design of the Gamma network is analyzed in terms of block structure. The analysis reveals the asymmetry of its duplicate links, and an alternate design in the form of the Kappa network is proposed. Its novel feature is the symmetry of duplicate links at the block level. This symmetry results in a simple control algorithm and enhanced fault tolerance. The relationship between the Kappa network and other existing fault-tolerant networks is briefly discussed.
VLSI Implementation of a Neural Network Model
Authors: Hans P. Graf, LAwrence D. Jackel, Wayne E. Hubbard
Venue: Computer (1988)

The authors describe a complementary metal-oxide-semiconductor (CMOS) very-large-scale integrated (VLSI) circuit implementing a connectionist neural-network model. It consists of an array of 54 simple processors fully interconnected with a programmable connection matrix. This experimental design tests the behavior of a large network of processors integrated on a chip. The circuit can be operated in several different configurations by programming the interconnections between the processors. Tests made with the circuit working as an associative memory and as a pattern classifier were so encouraging that the chip has been interfaced to a minicomputer and is being used as a coprocessor in pattern-recognition experiments. This mode of operation is making it possible to test the chip's behavior in a real application and study how pattern-recognition algorithms can be mapped in such a network.
Theory and Design of t-Error Correcting and d(d>t)-Unidirectional Error Detecting (t-EC d-UED) Codes
Authors: Der Jei Lin, Bella Bose
Venue: IEEE Transactions on Computers (1988)

The fundamental theory of t-error correcting and d(d>t)-unidirectional error detecting (t-EC d-UED) codes is given. Many construction methods for t-EC d-UED codes are developed. The encoding/decoding methods for these codes are described. The optimality of these codes is considered.
Observations on the portability of Ada I/O
Authors: Edmund R. Matthews
Venue: ACM SIGAda Ada Letters (1987)

I have been involved recently in developing reusable Ada components which are portable (in theory) across multiple systems using multiple compilers. One of the biggest problem areas in Ada portability aside from Chapter 13 issues is Chapter 14, Ada I/O. This paper represents an informal collection of my working notes on the portability problems of Chapter 14. These notes are based on my experience with a wide variety of compilers on an even larger set of hardware. I have purposefully not mentioned any compilers by name as I only wish to show the differences between implementations and do not wish to imply that any compiler is better than any other. While I/O is inherently non-portable, packages of common I/O functions such as those described in Chapter 14 can be specified in a manner which ensures maximum portability. There are too many loopholes and areas for implementor interpretation in current Ada 1.0; I hope to see more stringent I/0 specifications in 1988.
Concurrency control in database structures with relaxed balance
Authors: O. Nurmi, E. Soisalon-Soininen, D. Wood
Venue: Proceedings of the sixth ACM SIGACT-SIGMOD-SIGART symposium on Principles of database systems (1987)

We consider the separation of rebalancing from updates in several database structures, such as B-trees for external and AVL-trees for internal structures. We show how this separation can be implemented such that rebalancing is performed by local background processes. Our solution implies that even simple locking schemes (without additional links and copies of certain nodes) for concurrency control are efficient in the sense that at any time only a small constant number of nodes must be locked.
Why reading was slower from CRT displays than from paper
Authors: John D. Gould, Lizette Alfaro, Rich Finn, Brian Haupt, Angela Minuto
Venue: ACM SIGCHI Bulletin (1986)

Experiments, including our own (Gould et al., 1982; 1984; 1986), have shown that people read more slowly from CRT displays than from paper. Here we summarize results from a few of our fifteen experiments that have led us to conclude that the explanation centers on the image quality of the CRT characters. Reading speeds equivalent to those on paper were found when the CRT displays contained character fonts that resembled those on paper (rather than dot matrix fonts, for example), had a polarity of dark characters on a light background, were anti-aliased (e.g., contained grey level), and were shown on displays with relatively high resolution (e.g., 1000 x 800). Each of these variables probably contributes something to the improvement, but the trade-offs have not been determined. Other general explanations for the reading speed difference that can be excluded include some inherent defect in CRT technology itself or personal variables such as age, experience, or familiarity at reading from CRT displays.
LUSTRE: a declarative language for real-time programming
Authors: P. Caspi, D. Pilaud, N. Halbwachs, J. A. Plaice
Venue: Proceedings of the 14th ACM SIGACT-SIGPLAN symposium on Principles of programming languages (1987)

LUSTRE is a synchronous data-flow language for programming systems which interact with their environments in real-time. After an informal presentation of the language, we describe its semantics by means of structural inference rules. Moreover, we show how to use this semantics in order to generate efficient sequential code, namely, a finite state automaton which represents the control of the program. Formal rules for program transformation are also presented.
A Method for Enforcing Integrability in Shape from Shading Algorithms
Authors: Robert T. Frankot, Rama Chellappa
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (1988)

An approach for enforcing integrability, a particular implementation of the approach, an example of its application to extending an existing shape-from-shading algorithm, and experimental results showing the improvement that results from enforcing integrability are presented. A possibly nonintegrable estimate of surface slopes is represented by a finite set of basis functions, and integrability is enforced by calculating the orthogonal projection onto a vector subspace spanning the set of integrable slopes. The integrability projection constraint was applied to extending an iterative shape-from-shading algorithm of M.J. Brooks and B.K.P. Horn (1985). Experimental results show that the extended algorithm converges faster and with less error than the original version. Good surface reconstructions were obtained with and without known boundary conditions and for fairly complicated surfaces.
A petri net reduction algorithm for protocol analysis
Authors: C V Ramamoorthy, Y Yaw
Venue: Proceedings of the ACM SIGCOMM conference on Communications architectures protocols (1986)

Petri net is a powerful model for analyzing communication protocols because they share many common properties. Currently, protocol analysis suffers the state explosion problem especially for error-recoverable protocols and multi-party protocols. Protocol synthesis relieves this problem by generating new and complicated protocols from simple subsets of the protocol models. Reduction analysis provides theoretical ground for correct synthesis or expansion. Thus, reduction is a very important research area. In this paper, we present a general Petri net reduction algorithm that reduces the number of states while preserving all desirable and undesirable properties. To the best of our knowledge, this is the first general Petri net reduction algorithm for protocol analysis. We first present and extend Dong's [DON 83] definition of WBMs to include more subnets as WBMs. To render the reductions automated, a new concept of simple well-behaved modules (SWBMs) is introduced. Recursively performing reductions of SWBMs, complicated WBMs can be reduced. A main program is written to implement this recursive procedure. The problem is then reduced to finding conditions for SWBMs. We do this by progressing from simpler SWBMs to more complicated ones, i.e., from single-arc ones to multi-arcs ones. Finally, we demonstrate the usefulness of this algorithm by applying it to the state exploration in protocol synthesis. Other applications such as error detection, performance evaluation, and software engineering will be discussed in future.
Determining the extent of lookahead in syntactic error repair
Authors: Jon Mauney, Charles N. Fischer
Venue: ACM Transactions on Programming Languages and Systems (TOPLAS) (1988)

Many syntactic error repair strategies examine several additional symbols of input to guide the choice of a repair; a problem is determining how many symbols to examine. The goal of gathering all relevant information is discussed and shown to be impractical; instead we can gather all information relevant to choosing among a set of &ldquo;minimal repairs.&rdquo; We show that finding symbols with the property &ldquo;Moderate Phrase-Level Uniqueness&rdquo; is sufficient to establish that all information relevant to these minimal repairs has been seen. Empirical results on the occurrence of such symbols in Pascal are presented.
Pseudorandom Testing
Authors: Kenneth D. Wagner, Cary K. Chin, Edward J. McCluskey
Venue: IEEE Transactions on Computers (1987)

Algorithmic test generation for high fault coverage is an expensive and time-consuming process. As an alternative, circuits can be tested by applying pseudorandom patterns generated by a linear feedback shift register (LFSR). Although no fault simulation is needed, analysis of pseudorandom testing requires the circuit detectability profile.
An Application of Structural Modeling to Software Requirements Analysis and Design
Authors: K. Matsumura, H. Mizutani, M. Arai
Venue: IEEE Transactions on Software Engineering (1987)

In software development, it has been pointed out that software engineers must pay attention to software requirements definition. One of the important problems in software engineering is to rationalize the processes from requirements definition to design. Computer tools are most useful and efficient for this purpose. This paper proposes a computer-aided software design system (CASDS), which supports software engineers with a series of structural modeling. As is well-known in systems planning, structural modeling helps to extract concepts from many fuzzy requirements. This system contains three structural modeling methods. They are used 1) to determine functional terms from fuzzy software requirements, 2) to obtain modules by structuring the functions with respect to the data flows, and 3) to make a program skeleton by imposing control flows on the functional elements obtained by breaking down the modules.
The JADE interpreter: a RISC interpreter for syntax directed editing
Authors: C. F. Clark
Venue: Papers of the Symposium on Interpreters and interpretive techniques (1987)

This paper describes key features of an interpreter for a language-based editor. The interpreter unites in a RISC framework features which have been used in other domains. The paper examines each feature's integration into the RISC framework.
Taxonomic ambiguities in category variations needed to support machine conceptualization
Authors: L J Mazlack
Venue: Proceedings of the ACM SIGART international symposium on Methodologies for intelligent systems (1986)

This is a theoretical expositional exploration into the underlying needs of concept formation. The main purpose is to identify and discuss the differing forms of categorization in the context of possible machine learning and representation of those concepts. Conceptualization is the process of developing the abstractions that are needed to support reasoning. The formation of the machine equivalent of human concepts is critical to the development of a general, machine based reasoning capacity. An aid in understanding conceptual categorization is prototype theory. It helps to identify the building block tools that are used to construct categories and taxonomies. When developing taxonomic structures, framing conflicts can occur in terms of how things should be clustered together, what should be the relative hierarchal levels, and what should be subordinate to what.
The FinnAPL keyword editor
Authors: Juhani Sandberg, Olli Paavola, Tauno Ylinen
Venue: Proceedings of the international conference on APL: APL in transition (1987)

Most terminals used do not support APL characters. Although many microcomputers support soft fonts and some interpreters are equipped with a keyword option, and end-user APL applications should do without APL characters when in normal use, there still is a need for managing APL programming from terminals without APL characters. The authors propose a simple toolbox for the management of such situations in VM/SP environment.
Pi: a case study in object-oriented programming
Authors: T. A. Cargill
Venue: Conference proceedings on Object-oriented programming systems, languages and applications (1986)

Pi is a debugger written in C + +. This paper explains how object-oriented programming in C + + has influenced Pi's evolution. The motivation for object-oriented programming was to experiment with a browser-like graphical user interface. The first unforeseen benefit was in the symbol table: lazy construction of an abstract syntax-based tree gave a clean interface to the remainder of Pi, with an efficient and robust implementation. Next, though not in the original design, Pi was easily modified to control multiple processes simultaneously. Finally, Pi was extended to control processes executing across multiple heterogeneous target processors.
Oblog-2: A hybrid knowledge representation system for defeasible reasoning
Authors: T. F. Gordon
Venue: Proceedings of the 1st international conference on Artificial intelligence and law (1987)

Oblog-2 is a hybrid knowledge representation system comparable to Krypton and KL-TWO. It combines a terminological reasoner with a Prolog-like inference mechanism. The terminological component supports the description of type and attribute taxonomies. Entities are instances of a set of types. Procedures for determining the values of attributes are Horn clause rules indexed by type. The known types of an entity determine its set of applicable rules, which changes as our knowledge about the types of the entity is refined, supporting a form of defeasible reasoning. Oblog-2 has been designed for modeling legal domains. Laws can be represented as general rules with exceptions, a technique traditionally used in the law, together with burden of proof rules, for reaching decisions when less than perfect information is available.