ppxscal/embedding_network huggingface dataset:
The standards factor
Authors: J. Meads
Venue: ACM SIGCHI Bulletin (1989)

I don't have any news to report this time around. It isn't necessarily that nothing is happening---it's just that I haven't heard about it. Keeping track of what is happening in the standards arena is major effort and the time available to me for this during the past few months has been minimal.
Usability and hardcopy manuals: evaluating research designs and methods
Authors: Barbara Mirel
Venue: ACM SIGDOC Asterisk Journal of Computer Documentation (1990)

For the past decade, testing the usability of print software manuals has become a mature area of study, characterized by a wide range of qualitative and quantitative methods. Some of the most common methods include field observations, surveys, interviews, protocol analyses, focus groups, iterative testing, and quasi-experimental lab simulations [1]. Such diverse approaches to usability testing offer an opportunity for complementary inquiries and analyses. For example, findings from focus groups can provide key questions for experimental researchers to pursue in greater depth and with greater possibility for generalizability. Essentially, this complementary approach envisions an interaction between the academy, with its propensity toward pure, experimental research, and industry, with its more applied approaches for alpha and beta testing. Patricia Wright, a specialist in usability studies, has long argued that integrating pure and applied research is the best means for expanding our knowledge about effective document design [2; 3]. Such integration reveals both the immediately applicable aspects of effective manuals and the more theoretical boundaries in textual features that make a difference for general types of tasks, readers, and contexts of use. In order to realize the potential of conducting a conversation between pure and applied research, documentation researchers and practitioners must clearly understand the limitations that exist in the conclusions that investigators derive from specific methods of inquiry. In this article, I look solely at experimental usability tests that rely on quantitative methods of analysis. I analyze the ways in which the research designs and questions of the past ten years of experimental studies affect the strength of cumulative conclusions and the confidence we can have in those conclusions. My purpose is not to give preference to experimental research as the most important approach to usability testing. Far from it. Rather my critical review has two purposes: (1) to facilitate the dialogue between academic and industrial researchers by identifying the limits of current experimental findings; and (2) to propose research agendas and designs for future experimental usability tests that can strengthen the conclusions that such researchers offer for practical consideration. My evaluation of ten years of experimental usability studies shows that many of the conclusions of these studies are not strong enough to serve as valid, generalizable, and replicable foundations for subsequent research, be it pure or applied. These conclusions can be strengthened by designing studies that pay more attention to the sequencing and integration of related investigations and that institute better controls for sample selection, size, and composition. This article discusses my overall findings, the details of which I will develop more fully in my presentation.
Keeping a consulting system on course
Authors: Stephen C. Andrade, Kathleen S. Brown
Venue: Proceedings of the 16th annual ACM SIGUCCS Conference on User Services (1988)

All to often, User Services staff view the absence of complaints as a primary source of evaluation and feedback of services. As a frontline emergency service, the consulting effort is one of the most visible and critical elements of effective user support. It is difficult to collect data about the effectiveness and quality of frontline consulting services, but many techniques provide enlightening information for user services staff. At Brown University collecting data and feedback about the consulting process is a priority for Academic and User Services. A Consulting Task Group was formed to collect feedback from a variety of sources and to prepare a plan and implement a new structure (where necessary) for our computer consulting system. We quickly identified areas where immediate improvement resulted and committed to the longer term project of collecting data. By keeping data from &ldquo;support log forms&rdquo; at the point of consulting contact we have gained the following insights: the profiles of the computing user community &mdash; who when how are questions being asked what the typical and atypical questions are and how frequently they are asked the percentage of questions referred to expert sources the management issues of allocation of resources, revision of training curriculum, and restructuring of consulting to meet Brown's needs. Computer consulting takes on many forms and can be a complex and time consuming task. Knowing the key elements of the consulting environment, such as the volume of questions, frequency of questions, types of questions, and referral path of questions, can have a positive impact on the management and effectiveness of services. But data collection through log forms is not the only technique we have used for collecting information on the health of the consulting system at Brown. Additional techniques of gathering information about the consulting effort have also proved to be important, such as conducting &ldquo;key user information sessions&rdquo;. We have also emphasized taking the time to gather street smarts and conduct more housecalls; an aspect of consultant savvy that tends to be neglected because of the frantic pace of consulting. The results of Brown's first phase of support log data and key user information sessions will be reviewed in this paper. The presentation will include statistics, graphs, and anecdotal reviews of the data collection effort. Handouts will be available. Techniques for gathering information will be offered, as well as how such information can be used to improve the quality of consulting services.
Ray tracing trimmed rational surface patches
Authors: Tomoyuki Nishita, Thomas W. Sederberg, Masanori Kakimoto
Venue: ACM SIGGRAPH Computer Graphics (1990)

This paper presents a new algorithm for computing the points at which a ray intersects a rational B eacute;zier surface patch, and also an algorithm for determining if an intersection point lies within a region trimmed by piecewise B eacute;zier curves. Both algorithms are based on a recent innovation known as B eacute;zier clipping, described herein. The intersection algorithm is faster than previous methods for which published performance data allow reliable comparison. It robustly finds all intersections without requiring special preprocessing.
Pre-and post-processing for data efficiency in large-scale computer simulations
Authors: T. K. Gardenier
Venue: Proceedings of the 21st conference on Winter simulation (1989)

Large-scale computer simulations demand the availability of methods to plan for simulation runs, and to economize on data requirements. Efforts to link input to various output measures have used the expertise of statistical experiment design in the following ways: (a) generating sub-fractions of a full factorial experiment design, still maintaining orthogonality for efficient estimation: (b) capitalizing on the primary network of synergistic and modulative interactions so that those parameters can be planned into the pre-processor requirements: (c) deriving methods to conduct a profiling analysis on a set of output measures of merit. The author has developed the PRE-FRIM and POST-PRIM systems, the following major features of which are presented here: (a) preprocessor types oriented toward screening versus estimating synergies/antagonisms: (b) mathematical and statistical requirements of orthogonality and balance: (c) regression-oriented software and POST-PRIM profiling approach to dealing with output measures: use of rotatable graphics; (d) tracing time-indexed output through CTSS, a major component of POST-PRIM to monitor output trends.
Operation of class sums on permutation modules
Authors: H. W. Gollan, T. W. Ostermann
Venue: Journal of Symbolic Computation (1990)

Let G be a finite group and F a finite field. Then the conjugacy class sums form an F-basis of the centre of the group algebra FG and consequently they play an important role in modular representation theory. In this paper we present an efficient algorithm for calculating class sums in the case of permutation modules. It is applied to calculate block idempotents, which enables us to get a decomposition of permutation modules. The method has been implemented as a CAYLEY-procedure and we will give two examples. Finally, in the case of an arbitrary induced module we show that there is no advantage in restricting attention to class representatives.
Performance Analysis of a Generalized Concurrent Error Detection Procedure
Authors: Douglas M. Blough, Gerald M. Masson
Venue: IEEE Transactions on Computers (1990)

A general procedure for error detection in complex systems, called the data block capture and analysis monitoring process, is described and analyzed. It is assumed that, in addition to being exposed to potential external fault sources, a complex system will in general always contain embedded hardware and software fault mechanisms which can cause the system to perform incorrect computations and/or produce incorrect output. Thus, in operation, the system continuously moves back and forth between error and no-error states. These external fault sources or internal fault mechanisms are extremely difficult to detect. The data block capture and analysis monitoring process is concerned with detecting deviations from the normal performance of the system, known as errors, which are symptomatic of fault conditions. The process consists of repeatedly recording a fixed amount of data from a set of predetermined observation lines of the system being monitored (i.e. capturing a block of data) and then analyzing the captured block in an attempt to determine whether the system is functioning correctly.
A novel approach to system-level fault tolerance in hypercube multiprocessors
Authors: P. Banerjee, C. B. Stunkel
Venue: Proceedings of the third conference on Hypercube concurrent computers and applications: Architecture, software, computer systems, and general issues - Volume 1 (1988)

This paper addresses the issue of fault tolerance in hypercube architectures. Most of the recently proposed schemes of fault tolerance in parallel architectures address mainly the issue of reconfiguration of a parallel architecture once a faulty processor is identified. The schemes assume the existence of an off-line diagnosis strategy which locates the faulty processor. We propose the detection and location of faulty processors concurrently with the actual execution of parallel applications on the hypercube using a novel scheme of algorithm-based fault detection. The basic idea used is to propose low cost fault detection and location schemes using high-level encodings on the data that are tailored to the algorithms being executed on the parallel machine. We have implemented system-level fault detection mechanisms for various parallel applications on a 16-processor Intel iPSC hypercube multiprocessor. In this paper we discuss the results of one such application, namely, Gaussian Elimination which is an extremely useful algorithm for solving a set of linear equations. We have performed extensive studies of fault coverage of our system level fault detection schemes in the presence of finite precision arithmetic which affects our system level encodings.
Process-originated migration in a heterogeneous environment
Authors: F. B. Dubach, C. M. Shub
Venue: Proceedings of the 17th conference on ACM Annual Computer Science Conference (1989)

Process Originated Migration in a distributed system comprised of both Sun and MicroVax workstations is described. An introductory section characterizes distributed systems, distinguishes them from network systems, and summarizes existing work in process migration. The motivations for both process originated migration and heterogeneous migration are presented. The assumptions and design criteria as well as the design choices made for leverage, simplicity, and performance are provided. The design and its implementation are provided. Several extensions are presented and conclusions are drawn.
A Representation Theory for Morphological Image and Signal Processing
Authors: P. Maragos
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (1989)

A unifying theory for many concepts and operations encountered in or related to morphological image and signal analysis is presented. The unification requires a set-theoretic methodology, where signals are modeled as sets, systems (signal transformations) are viewed as set mappings, and translational-invariant systems are uniquely characterized by special collections of input signals. This approach leads to a general representation theory, in which any translation-invariant, increasing, upper semicontinuous system can be presented exactly as a minimal nonlinear superposition of morphological erosions or dilations. The theory is used to analyze some special cases of image/signal analysis systems, such as morphological filters, median and order-statistic filters, linear filters, and shape recognition transforms. Although the developed theory is algebraic, its prototype operations are well suited for shape analysis; hence, the results also apply to systems that extract information about the geometrical structure of signals.
A Survey of Synchronization Methods for Parallel Computers
Authors: Anne Dinning
Venue: Computer (1989)

An examination is given of how traditional synchronization methods influence the design of MIMD (multiple-instruction multiple-data-stream) multiprocessors. She provides an overview of MIMD multiprocessing and goes on to discuss semaphore-based implementations (Ultracomputers, Cedar, and the Sequent Balance/21000), monitor-based implementations (the HM/sup 2/p) and implementations based on message-passing (HEP, the BBN Butterfly and the Transputer).
A preceding activation scheme with graph unfolding for the parallel processing system-array
Authors: H. Yamana, T. Hagiwara, J. Kohdate, Y. Muraoka
Venue: Proceedings of the 1989 ACM/IEEE conference on Supercomputing (1989)

The purpose of this paper is to propose and evaluate a new scheme, called the Preceding Activation Scheme with Graph Unfolding, which translates a FORTRAN program into a dataflow graph and executes it efficiently. The problems in restructuring a FORTRAN program into a dataflow graph are that (1) a FORTRAN program is not written in a single assignment rule and (2) it has an explicit control flow. These problems result in little parallelism because many gate-operations, such as T/F gates, are introduced in the dataflow graph to synchronize the data movement. Therefore, discarding these gate-operations is the key to exposing parallelism in a FORTRAN program. In this paper, the preceding activation scheme with graph unfolding is proposed to discard these gate-operations. Then, the result of the performance evaluation by the -Harray- software simulator is presented. It is shown that the execution speed with the proposed scheme for flow graphs without backward branches is about 1.5 times as fast as that with the extended activation scheme which initiates the execution only after it is confirmed that a basic block will be selected at a conditional branch. Moreover, the execution speed is 2.7 times as fast as that with the extended activation scheme if a flow graph including backward branches are unfolded by the proposed scheme.
How would your favourite user model cope with these scenarios?
Authors: R. M. Young, P. Barnard, T. Simon, J. Whittington
Venue: ACM SIGCHI Bulletin (1989)

In a paper presented at the 1987 CHI conference (Young amp; Barnard, 1987), we proposed the use of scenarios as one methodological route to the development of user models of broader scope. In this article we summarise the argument and present five such scenarios as a challenge to the state of the art in user modelling. We invite the reader to ponder the question: How well would your favourite user modelling technique handle some, most, or all of these scenarios? And have you any further scenarios to add to those presented here?
Computer accessibility for federal workers with disabilities: it's the law
Authors: Richard E. Ladner
Venue: Communications of the ACM (1989)

In 1986, Congress passed Public Law 99-506, the "Rehabilitation Act Amendments of 1986." This law, amending the famous Rehabilitation Act of 1973, contains a small section, titled "Electronic Equipment Accessibility," Section 508, which may have significant impact on the design of computer systems and their accessibility by workers with disabilities. The bill became law when it was signed by former President Reagan on October 21, 1986. The purpose of this article is to inform concerned computer professionals of Section 508, outline the guidelines and regulations pursuant to the law, describe some of the reaction to the guidelines and regulations, and describe some of the challenges for the future in meeting the computer accessibility needs of users with disabilities. Section 508 was developed because it was realized that government offices were rapidly changing into electronic offices with microcomputers on every desk. In order for persons with disabilities to keep their jobs or gain new employment in the government, Congress decided it was necessary to make provisions to guarantee accessibility to microcomputers and other electronic office equipment. The driving principle behind Section 508 can be found in Section 504 of the Rehabilitation Act of 1973 which states: No otherwise qualified handicapped individual in the United States . . . shall, solely by reason of his handicap, be excluded from the participation in, be denied the benefits of, or be subjected to discrimination under any program or activity receiving Federal financial assistance. It should be stated off the top that the scope of Section 508 is not as broad as Section 504. In particular, Section 508 only applies to direct purchases by the federal government and not to purchases made by all programs receiving government funding. Section 508 does not specify what the guidelines should be nor does it delineate a philosophy on which to base the guidelines. A committee established by the National Institute on Disability and Rehabilitation Research (NIDRR) and the General Services, Administration (GSA), in consultation with the electronics industry, rehabilitation engineers, and disabled computer professionals worked for a year developing the philosophy and guidelines which will significantly affect the purchase of electronic office equipment, including computers and software, by the federal government, the largest computer customer in the world.
The Flex architecture, a high speed graphics processor
Authors: Ivor Page, Jeff Niehaus
Venue: ACM SIGARCH Computer Architecture News (1988)

The design of a computer graphics pipeline is examined in detail using high speed floating point multiply/add units and cross bar switches as building blocks. Various parallel and pipelined arrangements are explored for simulating the individual stages of the pipe. It is shown that a highly versatile architecture, entitled the FLEX ARCHITECTURE based on four processors and a 16 port switch, can be used efficiently to simulate all stages of the graphics pipeline and, for high performance systems, multiple flex units are considered. Estimates of performance are developed using a particular set of components available from Texas Instruments. Designs with performance in excess of one to two million vectors per second are feasible.
An event language for building user interface frameworks
Authors: N. V. Carlsen, N. J. Christensen, H. A. Tucker
Venue: Proceedings of the 2nd annual ACM SIGGRAPH symposium on User interface software and technology (1989)

Languages based on the event model are widely regarded as expressive and flexible notations for the specification of interactive graphical user interfaces. However, until now, they have only been used to specify and implement the dialogue control component of user interfaces. This paper presents an extension of the event model. A computable notation, the event language, based on this is used to construct a complete user interface framework. The framework forms the runtime component of a UIMS. The event language allows the modular construction of complex event systems. This is supported by the addition of a tagged addressing mode. Furthermore, the control structure of event handlers is extended with exception management, permitting unspecified events and thereby facilitating the use of predefined building blocks. A general purpose run-time framework for user interfaces has been constructed using the event language. We present the architecture of the presentation component of this framework including the window manager and the I/O model.
An incremental method for generating prime implicants/implicates
Authors: Alex Kean, George Tsiknis
Venue: Journal of Symbolic Computation (1990)

Given the recent investigation of Clause Management Systems (CMSs) for ArtificialIntelligence applications, there is an urgent need for an efficient incremental method for generating prime implicants. Given a set of clauses F, a set of prime implicants II of F and a clause C"1 the problem can be formulated as finding the set of prime implicants for II U {C}. Intuitively, the property of implicants, being prime implies that any effort to generate prime implicants from a set of prime implicants will not yield any new prime implicants but themselves. In this paper, we exploit the properties of prime implicants and propose an incremental method for generating prime implicants from a set of existing prime implicants plus a new clause. The correctness proof and complexity analysis of the incremental method are presented, and the intricacy of subsumptions in the incremental method is also examined. Additionally, the role of prime implicants in the CMS is also mentioned.
Lifetime analysis of dynamically allocated objects
Authors: C. Ruggieri, T. P. Murtagh
Venue: Proceedings of the 15th ACM SIGPLAN-SIGACT symposium on Principles of programming languages (1988)

The choice of binding time disciplines has major consequences for both the run-time efficiency of programs and the convenience of the language expressing algorithms. Late storage binding time, dynamic allocation, provides the flexibility necessary to implement the complex data structures common in today's object oriented style of programming. In this paper we show that compile-time lifetime analysis can be applied to programs written in languages with static type systems and dynamically allocated objects, to provide earlier storage binding time for objects, while maintaining all the advantages of dynamic allocation.
Towards abstracting complex database objects: generalization, reduction, and unification of set-type objects
Authors: K. Tanaka, M. Yoshikawa
Venue: Lecture notes in computer science on ICDT '88 (1988)

Representing and manipulating complex (database) objects are important issues in the semantic database models and object-oriented database models, most of which have a rich expressive power for complex objects. In this paper, we will focus on the manipulation of complex objects, and introduce the notions and the operations for abstracting complex objects. We introduce the notion of &ldquo;element-based&rdquo; generalization relationships between complex objects, and two new abstraction operators: reduction and unification. Their algebraic properties are then formally investigated especially for &ldquo;set-type&rdquo; complex objects.