ppxscal/embedding_network huggingface dataset:
Effective video screen displays: cognitive style and cuing effectiveness
Authors: Kenneth A. Cory
Venue: ACM SIGCHI Bulletin (1994)

Cues are often added to video screen presentations to help users focus on the most important sections of text. The effectiveness of cues is usually thought to be inherent within the characteristics of the cues. In this case, an experiment was conducted to determine whether the effectiveness of two cuing techniques is dependent upon a user's cognitive style. The Thurstone and Jeffrey Closure Flexibility Test was used to identify 75 subjects high in the field independent cognitive style and another 75 high in the field dependent cognitive style. Twenty-five members of each cognitive style group were exposed to one of the cuing techniques; either underlining or highlighting. A control group was exposed to no cue. The cues were used to called attention to important words and phrases appearing in a tutorial that explained how to use the Grolier Electronic Encyclopedia in CD-ROM format. The dependent variable was time taken to finish the tutorial.Results were evaluated according to an analysis of variance and a t-test. Cognitive style was demonstrated to be a determining factor with field independent subjects finishing the tutorial significantly faster than the field dependent subjects.The faster performance of field independent subjects while interacting with a video screen display was attributed to the fact that they tend to perceive objects more analytically and to separate objects from their embedded backgrounds, as opposed to field dependent subjects who tend to perceive objects in a global context.
A game theoretic approach to distributed artificial intelligence and the pursuit problem (abstract)
Authors: Ran Levy, Jeffrey S. Rosenschein
Venue: ACM SIGOIS Bulletin (1992)

As part of an effort to define a unified formal semantics for beliefs, desires and action, this paper sketches a model theory for the axiological aspects of agent theory: hedonic states, likes, goals and values. It pays particular attention to modelling the intensity of likes. The main intuition underlying the model theory is that the axiological aspects of agent theory can be modelled through computational generalisations of physical dynamics. Computational analogues of force, mass and potential are offered.
Belief formation and system success: when do responses to satisfaction instruments reflect system attributes?
Authors: Kieran Mathieson
Venue: Proceedings of the 1993 conference on Computer personnel research (1993)

Measuring information system (IS) success is a key problem for IS researchers. A common measure of success is user satisfaction. Two general conditions must be met before responses to a satisfaction instrument will accurately reflect a system's characteristics. First, users' beliefs must accurately reflect system attributes. Second, the satisfaction instrument must be psychometrically sound. IS researchers have focused on the second issue, virtually ignoring the first. This paper discusses the conditions under which users' beliefs about systems are accurate. It draws together ideas from social and cognitive psychology, marketing and other fields. The objective is not to discourage the use of satisfaction instruments, but to identify situations in which they accurately measure system attributes.
The local Time Warp approach to parallel simulation
Authors: Hassan Rajaei, Rassul Ayani, Lars-Erik Thorelli
Venue: Proceedings of the seventh workshop on Parallel and distributed simulation (1993)

The two main approaches to parallel discrete event simulation &ndash; conservative and optimistic &ndash; are likely to encounter some limitations when the size and complexity of the simulation system increases. For such large scale simulations, the conservative approach appears to be limited by blocking overhead and sensitivity to lookahead, whereas the optimistic approach may become prone to cascading rollbacks, state saving overhead, and demands for larger memory space. These drawbacks restrict the synchronization schemes based on each of the two approaches from scaling up. A combined approach may resolve these limitations, while preserving and utilizing potential advantages of each method. However, the schemes proposed so far integrate the two views at the same level, i.e. local to a logical process, and hence may not be able to fully solve the problems. In this paper we propose the Local Time Warp method for parallel discrete-event simulation and present a novel synchronization scheme for it called HCTW. The new scheme hierarchically combines a Conservative Time Window algorithm with Time Warp and aims at reducing cascade rollbacks, sensitivity to lookahead, and the scalability problems. Local Time Warp is believed to be suitable for parallel machines equipped with thousands of processors and thus an appropriate candidate for simulation of large and complex systems.
Reasoning about strings in databases
Authors: Gösta Grahne, Matti Nykänen, Esko Ukkonen
Venue: Proceedings of the thirteenth ACM SIGACT-SIGMOD-SIGART symposium on Principles of database systems (1994)

In order to enable the database programmer to reason about relations over strings of arbitrary length we introduce alignment logic, a modal extension of relational calculus. In addition to relations, a state in the model consists of a two-dimensional array where the strings are aligned on top of each other. The basic modality in the language (a transpose, or &ldquo;slide&rdquo;) allows for a rearrangement of the alignment, and more complex formulas can be formed using a syntax reminiscent of regular expressions, in addition to the usual connectives and quantifiers. It turns out that the computational counterpart of the string-based portion of the logic is the class of multitape two-way finite state automata, which are devices particularly well suited for the implementation of string matching. A computational counterpart of the full logic is obtained from relational algebra by extending the selection operator into filters based on these multitape machines. Safety of formulas in alignment logic implies that new strings generated from old ones have to be of bounded length. While an undecidable property in general, this boundedness is decidable for an important subclass of formulas. As far as expressive power is concerned, alignment logic includes previous proposals for querying string databases, and gives full Turing computability. The language can be restricted to define exactly regular sets and sets in the polynomial hierarchy.
Discrimination between object-oriented and process approaches to systems analysis for functional decomposition of existing systems
Authors: Frank G. Duserick
Venue: Proceedings of the 1993 conference on Computer personnel research (1993)

Object oriented methodology, as an innovation in information technology, has emerged as an alternative to the process method for the analysis and design of systems. Recent Activity in Object Oriented Systems Analysis (OOSA) has suggested that OOSA is theoretically better than a process approach for systems analysis because of the former's ease of maintenance, reusability and understandability. This research seeks to validate this assumption. A pilot study involving 60 undergraduate business majors reveals that an object-oriented approach may provide better results than a process approach to systems analysis.
Half-Transitive Graphs of Prime-Cube Order
Authors: Ming-Yao Xu
Venue: Journal of Algebraic Combinatorics: An International Journal (1992)

We call an undirected graph X half-transitive if the automorphism group Aut X of X acts transitively on the vertex set and edge set but not on the set of ordered pairs of adjacent vertices of X. In this paper we determine all half-transitive graphs of order p3 and degree 4, where p is an odd prime&semi; namely, we prove that all such graphs are Cayley graphs on the non-Abelian group of order p3 and exponent p2, and up to isomorphism there are exactly (p &minus; 1)/2 such graphs. As a byproduct, this proves the uniqueness of Holt's half-transitive graph with 27 vertices.
A nontraditional computer graphics course for computer science students
Authors: Zhigang Xiang
Venue: ACM SIGGRAPH Computer Graphics (1994)

The recent theoretical and technological advancement in computer graphics has brought not only exciting changes to the computing field but also new challenges to computer science educators. One of the challenges is effective teaching of computer graphics to computer science students. Several speakers at the SIGGRAPH "91 educators' program addressed various aspects of this theme (Owen, 1991; Schweitzer, 1991; Clevenger, 1991). A SIGGRAPH '92 panel consisting of representatives from academia and industry exchanged ideas and viewpoints on issues ranging from syllabus to the role of graphics in a computer science curriculum. I had the pleasure of being a member of that panel and this paper is a further elaboration of my brief statement in the conference proceedings (Schaller, 1992, 1993).The Department of Computer Science at Queens College offers computer graphics as an elective at the senior level for undergraduate students. The department also offers computer graphics at the graduate level. Since the majority of our graduate students have had no prior training in computer graphics, the two courses do not constitute a one-year sequence and the following considerations are applicable to both cases.The traditional way of teaching computer graphics to computer science students places an emphasis on vector graphics. After some general introduction, discussion typically proceeds to graphical primitives and their attributes, then windowing and geometric transformations, followed by segments and interactive techniques, leading to the use of a standard library such as GKS. Additional 3-D topics may include representation, transformation, projection and hidden surface removal algorithms. Color, and especially shading models, are not discussed until near the end of the semester.While this traditional approach has made invaluable contributions to computer graphics education, it needs to be improved in order to keep up with the rapid growth of the field over the last several years. In the next section, I present a nontraditional syllabus along with a detailed explanation. Sample assignments are in section 3. A comparison of the two syllabi and concluding remarks are in section 4.The computer graphics course described in this paper is quite similar to the course taught by Scott Owen (Owen, 1994).
Reducing the variability of programmers' performance through explained examples
Authors: David F. Redmiles
Venue: Proceedings of the INTERACT '93 and CHI '93 conference on Human factors in computing systems (1993)

A software tool called EXPLAINER has been developed for helping programmers perform new tasks by exploring previously worked-out examples. EXPLAINER is based on cognitive principles of learning from examples and problem solving by analogy. The interface is based on the principle of making examples accessible through multiple presentation views and multiple representation perspectives. Empirical evaluation has shown that programmers using EXPLAINER exhibit less variability in their performance compared to programmers using a commercially available, searchable on-line manual. These results are related to other studies of programmers and to current methodologies in software engineering.
A decompositional approach to database constraint enforcement
Authors: Eugene Y. Sheng
Venue: Proceedings of the 1993 ACM conference on Computer science (1993)

This paper presents a decompositional approach to integrity constraint enforcement for very large database systems. The central theme of the paper is the development of the constraint decomposition theorem which can be used to decompose any complex constraint formula into a set of simpler constraint sub-formulas, each of which is a sufficient condition for the original constraint formula and they can be enforced independently of one another. By utilizing the decomposition theorem and the fact that both cost for checking each sub-formula and satisfiablity of each sub-formula may be different from one another, we developed a new constraint enforcement strategy which is much efficient than the previous approaches.
Representation in virtual space: visual convention in the graphical user interface
Authors: Loretta Staples
Venue: Proceedings of the INTERACT '93 and CHI '93 conference on Human factors in computing systems (1993)

The graphical user interface (GUI) typically provides a multi-windowed environment within a flat workspace or &ldquo;desktop.&rdquo; Simultaneously, however, controls for executing commands within this interface are increasingly being rendered three-dimensionally. This paper explores ways in which the space of the GUI desktop might be literally and figuratively deepened through the incorporation of visual devices that have emerged during the history of art&mdash;specifically, perspective and light effects. By enriching the visual vocabulary of the GUI, greater semantic complexity becomes sustainable.
Ada in Russia: an overview
Authors: Sergei I. Rybin
Venue: ACM SIGAda Ada Letters (1994)

An overall description of the history and current state of the Ada-situation in Russia is presented. Some key details of the situation are outlined. The Moscow State University is proposed as the base organization for international communication and cooperation with the Russian Ada community.
Formal parametric polymorphism
Authors: Martín Abadi, Luca Cardelli, Pierre-Louis Curien
Venue: Proceedings of the 20th ACM SIGPLAN-SIGACT symposium on Principles of programming languages (1993)

A polymorphic function is parametric if its behavior does not depend on the type at which it is instantiated. Starting with Reynolds' work, the study of parametricity is typically semantic. In this paper, we develop a syntactic approach to parametricity, and a formal system that embodies this approach: system R . Girard's system F deals with terms and types; R is an extension of F that deals also with relations between types. In R **, it is possible to derive theorems about functions from their types, or &ldquo;theorems for free&rdquo;, as Wadler calls them. An easy &ldquo;theorem for free&rdquo; asserts that the type &forall;XX&rarr; Bool contains only constant functions; this is not provable in F. There are many harder and more substantial examples. Various metatheorems can also be obtained, such as a syntactic version of Reynolds' abstraction theorem.
A new signature scheme based on the DSA giving message recovery
Authors: Kaisa Nyberg, Rainer A. Rueppel
Venue: Proceedings of the 1st ACM conference on Computer and communications security (1993)

In this paper we present a modification of the DSA which allows signatures with message recovery. The new public key signature scheme is then applied to create (a) an identity-based public key system without restrictions in trust and (b) a one-pass key exchange protocol with mutual authentication.
Leapfrogging: a portable technique for implementing efficient futures
Authors: David B. Wagner, Bradley G. Calder
Venue: ACM SIGPLAN Notices (1993)

A future is a language construct that allows programmers to expose parallelism in applicative languages such as MultiLisp [5] with minimal effort. In this paper we describe a technique for implementing futures, which we call leapfrogging, that reduces blocking due to load imbalance. The utility of leapfrogging is enhanced by the fact that it is completely platform-independent, is free from deadlock, and places a bound on stack sizes that is at most a small constant times the maximum stack size encountered during a sequential execution of the same computation. We demonstrate the performance of leapfrogging using a prototype implementation written in C++.
On Rank-Revealing Factorisations
Authors: Shivkumar Chandrasekaran, Ilse C. F. Ipsen
Venue: SIAM Journal on Matrix Analysis and Applications (1994)

The problem of finding a rank-revealing QR (RRQR) factorisation of a matrix $A$ consists of permuting the columns of $A$ such that the resulting QR factorisation contains an upper triangular matrix whose linearly dependent columns are separated from the linearly independent ones. In this paper a systematic treatment of algorithms for determining RRQR factorisations is presented. In particular, the authors start by presenting precise mathematical formulations for the problem of determining a RRQR factorisation, all of them optimisation problems. Then a hierarchy of "greedy" algorithms is derived to solve these optimisation problems, and it is shown that the existing RRQR algorithms correspond to particular greedy algorithms in this hierarchy. Matrices on which the greedy algorithms, and therefore the existing RRQR algorithms, can fail arbitrarily badly are presented. Finally, motivated by an insight from the behaviour of the greedy algorithms, the authors present "hybrid" algorithms that solve the optimisation problems almost exactly (up to a factor proportional to the size of the matrix). Applying the hybrid algorithms as a follow-up to the conventional greedy algorithms may prove to be useful in practice.
Implementing an irregular application on a distributed memory multiprocessor
Authors: Soumen Chakrabarti, Katherine Yelick
Venue: ACM SIGPLAN Notices (1993)

Parallelism with irregular patterns of data, communication and computation is hard to manage efficiently. In this paper we present a case study of the Gro&uml;bner basis problem, a symbolic algebra application. We developed an efficient parallel implementation using the following techniques. First, a sequential algorithm was rewritten in a transition axiom style, in which computation proceeds by non-deterministic invocations of guarded statements at multiple processors. Next, the algebraic properties of the problem were studied to modify the algorithm to ensure correctness in spite of locally inconsistent views of the share data structures. This was used to design data structures with very little overhead for maintaining consistency. Finally, an application-specific scheduler was designed and tuned to get good performance. Our distributed memory implementation achieves impressive speedups.
Applying series expansion to the inverse beta distribution to find percentiles of the F-distribution
Authors: Roger W. Abernathy, Robert P. Smith
Venue: ACM Transactions on Mathematical Software (TOMS) (1993)

Let 0 &le; 1 and F be the cumulative distribution function (cdf) of the F-Distribution. We wish to find xp such that F(xp|n1, n2) = p, where n1 and n2 are the degrees of freedom. Traditionally, xp is found using a numerical root-finding method, such as Newton's method. In this paper, a procedure based on a series expansion for finding xpis given. The series expansion method has been applied to the normal, chi-square, and t distributions, but because of computational difficulties, it has not been applied to the F-Distribution. These problems have been overcome by making the standard transformation to the beta distribution. The procedure is explained in Sections 3 and 4. Empirical results of a comparison of CPU times are given in Section 5. The series expansion is compared to some of the standard root-finding methods. A table is given for p = .90.
Computer graphics in the undergraduate biology laboratory
Authors: Robert V. Blystone
Venue: ACM SIGGRAPH Computer Graphics (1994)

Computer graphics use by biology undergraduate students is now a mainstay in the microanatomy course taught at Trinity University. By using desktop computer graphics, these students are able to take ownership of histological images in ways not possible just five years ago. Digital frame grabs of microscope slides serve as the basis of student produced graphics. These graphics allow the undergraduate students to dramatically improve their learning opportunities and to visualize biological microstructures. Analytical study, dimensional reconstructions, presentation graphics for laboratory practical exams, multimedia presented term projects and "digital legacies" are now a part of these students' cognitive armamentarium. A description of the activities of the class reliant on computer graphics follows.
Configurable REC
Authors: Gerardo Cisneros
Venue: ACM SIGPLAN Notices (1994)

This paper describes CREC, a library of C functions for compiling and executing REC programs whose operators and predicates are provided by the caller. Given a C program with a menu-based interactive interface, REC can be added as a programming language to the user interface by assigning menu choices to REC operators and predicates through entries in a table, and linking in the appropriate functions in CREC. Being a very concise language, REC programs are easy to write in an interactive context. The same conciseness allows the compiler to require only a small amount of space. Experience whereby the library benefitted some mathematics and physics programs is described.
Social plans: a preliminary report (abstract)
Authors: Anand S. Rao, Michael P. Georgeff, Elizabeth A. Sonenberg
Venue: ACM SIGOIS Bulletin (1992)

In this paper we describe a domain independent control structure for cooperating problem solving. This control structure is introduced at both conceptual and implementational levels and is further complemented by a descriptive example. The concepts presented in this paper are derived from a generic agent model based upon intentions, behavior and resources of agents. Agents are motivated to act according to their long term goals, desires, preferences, responsibilities and the like. Their actions are influenced by their perceived surroundings, which are other agents and the environment in which they operate.
Reducing recovery constraints on locking based protocols
Authors: G. Alonso, D. Agrawal, A. El Abbadi
Venue: Proceedings of the thirteenth ACM SIGACT-SIGMOD-SIGART symposium on Principles of database systems (1994)

Serializability is the standard correctness criterion for concurrency control. To ensure correctness in the presence of failures, recoverability is also imposed. Pragmatic considerations result in further constraints, for instance, the existing log-based recovery implementations that use before-images warrant that transaction executions be strict. Strict executions are restrictive, thus sacrificing concurrency and throughput. In this paper we identify the relation between the recovery mechanism and the restrictions imposed by concurrency control protocols. In particular, we propose a new inverse operation that can be integrated with the underlying recovery mechanism. In order to establish the viability of our approach, we demonstrate the new implementation by making minor modifications to the conventional recovery architecture. This inverse operation is also designed to avoid the undesirable phenomenon of cascading aborts when transactions execute conflicting write operations.
Using the co-existence approach to achieve combined functionality of object-oriented and relational systems
Authors: R. Ananthanarayanan, V. Gottemukkala, W. Kaefer, T. J. Lehman, H. Pirahesh
Venue: Proceedings of the 1993 ACM SIGMOD international conference on Management of data (1993)

Once considered a novelty, object oriented systems have now entered the mainstream. Their impressive performance and rich type systems have created a demand for object oriented features in other areas, such as relational database systems. We believe the current efforts to combine object oriented and relational features into a single hybrid system will fall short of the mark, whereas our approach, the co-existence approach, has the distinction of requiring far less work, but at the same time promising both the desired functionality and performance. We describe the attributes of our co-existing systems, an object oriented system (C++) and a relational system (Starburst), and show how this combination supports the desired features of both object-oriented and relational systems.