ppxscal/embedding_network huggingface dataset:
NEST: a network simulation prototyping testbed
Authors: A. Dupy, J. Schwartz, Y. Yemini, D. Bacon
Venue: Proceedings of the 21st conference on Winter simulation (1989)

This paper describes Nest, a graphical environment for distributed networked systems simulation and rapid-prototyping. Nest users can develop and test distributed systems and protocols (from crude models to actual system code) within simulated network scenarios. Nest represents an environment-based approach to simulation. Users view Nest as an extension of their standard UnixTM environment. Nest offers the generality of language-based simulation techniques and the efficiencies of model-based techniques. Users interact with Nest through standardized graphical interfaces. Nest permits the users to modify and reconfigure the simulation during execution. Thus, it is possible to study the dynamic response of a distributed system to failures or burst-loads. Nest is organized as a simulation server, responsible for execution of complex simulation scenarios, and client monitors responsible for simulation control. The client/server model permits distribution of Nest over a network environment. This permits migration of simulations to powerful remote computational servers as well as development of a shared multi-site simulation/integration testbed. Nest is portable and extensible. It has been ported to virtually all UnixTM variants and distributed since 1987 to over 150 sites worldwide. It has been used in scores of studies ranging from communication protocols, to distributed databases and operating systems as well as distributed manufacturing systems.
Suitening our nomenclature
Authors: L. Ramshaw
Venue: ACM SIGACT News (1989)

Donald E. Knuth has suggested an alternative name for a multiset that I like very much: a suite, as in a suite of rooms or a suite of dances. Please join me in replacing "multiset" and "bag" with "suite" in our mathematical lexicon.
Likelihood ratio derviative estimators for stochastic systems
Authors: P. W. Glynn
Venue: Proceedings of the 21st conference on Winter simulation (1989)

This paper discusses likelihood ratio derivative estimation techniques for stochastic systems. After a brief review of the basic concepts, likelihood ratio derivative estimators are presented for the following classes of stochastic processes: time homogeneous discrete-time Markov chains, non-time homogeneous discrete-time Markov chains, time homogeneous continuous-time Markov chains, semi-Markov processes, non-time homogeneous continuous-time Markov chains, and generalized semi-Markov processes.
An HCI continuing education curriculum for industry
Authors: M. M. Mantei
Venue: ACM SIGCHI Bulletin (1989)

A field becomes a valid science by having a body of knowledge which its members recognize as basic to the field. This knowledge includes a set of research questions which the field addresses, a set of methodologies applicable to the research questions, the small number of basic theories that guide the research and a large amount of detail on techniques, phenomenon and field specific definitions. The methodologies and the theories they embody are what constitutes the paradigm of the field. As research and serendipitous discoveries take place close to and within the membership of the field, the body of knowledge is expanded, remolded, revised and restructured.
Transferring skills from training to the actual work situation: the role of task application knowledge, action styles and job decision latitude
Authors: P. von Papstein, M. Frese
Venue: Proceedings of the SIGCHI conference on Human factors in computing systems (1988)

In a field study (29 engineers), the transfer from expertise acquired in training to software use at work was shown to be mediated by task application knowledge (i.e. knowledge used to connect skills learned in training with tasks at work). Moreover, person variables like setting long range goals and developing detailed plans and an organizational variable like job decision latitude (i.e. how much freedom do workers have to do their work) influenced the transfer process. People with high goal orientation and planfulness and with high job decision latitude showed a higher transfer.
Very high quality user interfaces and fast data filing using a PC
Authors: Jonny Österman
Venue: ACM SIGAPL APL Quote Quad (1990)

The user response to a computer system is very dependent on the user interface. In order to compete with other software products for the PC, it is important that it is easy for APL programmers to use the possibilities in the PC environment. These possibilities include a number of qualities which are not available in the mainframe environment. With a PC, speed is usually more important than in a mainframe. This increases the demand for fast file handling functions. This paper introduces a new way to implement fast and flexible file handling for data files with a fixed record length.
Finding eigenvalues and eigenvectors of unsymmetric matrices using a hypercube multiprocessor
Authors: G. A. Geist, R. C. Ward, G. J. Davis, R. E. Funderlic
Venue: Proceedings of the third conference on Hypercube concurrent computers and applications - Volume 2 (1989)

Distributed-memory algorithms for finding the eigenvalues and eigenvectors of a dense unsymmetric matrix are given. While several parallel algorithms have been developed for symmetric systems, little work has been done on the unsymmetric case. Our parallel implementation proceeds in three major steps: reduction of the original matrix to Hessenberg form, application of the implicit double-shift QR algorithm to compute the eigenvalues, and back transformations to compute the eigenvectors. Several modifications to our parallel QR algorithm, including ring communication and pipelining, are discussed and compared. Results and timings are given.
Natural language querying of historical databases
Authors: James Clifford
Venue: Computational Linguistics (1988)

In this paper we examine the connection between two areas of semantics, namely the semantics of historical databases and the semantics of natural language querying, and link them together via a common view of the semantics of time. Since the target application domain is an historical database, we present the essential features of the Historical Relational Database Model (HRDM), an extension to the relational model motivated by the desire to incorporate more "real world" semantics into a database at the conceptual level. We then present the essential features of QE-III, a formally defined English database query language whose semantic and pragmatic theory, based on a Montague-type semantics, makes explicit reference to the notion of denotation with respect to a moment of time. We demonstrate the use of this language to query an example historical database, and discuss the issues of how to provide both a semantic and a pragmatic interpretation for questions within a model-theoretic framework.
The neXT computer
Authors: T. Dietrich
Venue: ACM SIGSMALL/PC Notes (1989)

What's NeXT? NeXT is Steve Jobs. In September of 1985 Jobs was stripped of his authority at the very company he and his friend Steve Wozniak had created - Apple Computer, Inc. Apple Computer, one of the most successful computer companies ever, is viewed by many as the company that got the personal computer industry rolling. In fact, Apple's first computer, the Apple 1, was introduced in 1976' - almost six years before IBM introduced its infamous PC.
The myth: anyone can code the software of the requirements and design are...
Authors: J. A. Perkins
Venue: Proceedings of the conference on TRI-Ada '88 (1989)

The focus of this paper is the conjecture that the coding phase of a software system is difficult even in those instances where the functional requirements are well defined, the functional design is finalized, and the implementation issues are well understood. To study this conjecture, we examined an actual implementation of a stack to discover what decisions the programmer encounters when attempting to transform the functional design into operational software code. We examine decisions affecting the specification of the stack package as well as those affecting the implementation of the subprograms in the body of this package.
Computer science undergraduate capstone course
Authors: Clinton P. Fuelling, Anne-Marie Lancaster, Mark C. Kertstetter, R. Waldo Roth, William A. Brown
Venue: ACM SIGCSE Bulletin (1988)

Curriculum concerns of the computer science discipline continue to require refinements in this rapidly changing field. We have established curriculum guidelines and we have two years experience in the accrediting process of the CSAB. Remarks such as &ldquo;I do not consider the topic of &hellip; to be in the computer science discipline&rdquo; and &ldquo;At least the topic of &hellip; is not a capstone course&rdquo; are being made. The goal of this panel is to provide an open, probing platform for a discussion of the subject of a capstone course.
Performance enhancement through replication in an object-oriented DBMS
Authors: Eugene J. Shekita, Michael J. Carey
Venue: ACM SIGMOD Record (1989)

In this paper we describe how replicated data can be used to speedup query processing in an object-oriented database system. The general idea is to use replicated data to eliminate some of the functional joins that would otherwise be required for query processing. We refer to our technique for replicating data as field replication because it allows individual data fields to be selectively replicated. In the paper we describe how field replication can be specified at the data model level and we present storage-level mechanisms to efficiently support it. We also present an analytical cost model to give some feel for how beneficial field replication can be and the circumstances under which it breaks down. While field replication is a relatively simple notion, the analysis shows that it can provide significant performance gains in many situations.
Design methods of electron beam sensitive devices in NMOS and CMOS technologies
Authors: D. Micollet, B. Courtois
Venue: Microelectronic Engineering (1988)

This paper presents the basics for the design of electron beam sensitive devices intended to be used for the controllability of integrated circuits. For each part of the devices, different solutions are proposed and compared to allow the best choice. Two methods are detailed for further assemblings in electron beam sensitive devices.
Refined Fortran: an update
Authors: D. Klappholz, X. Kong, A. D. Kalis
Venue: Proceedings of the 1989 ACM/IEEE conference on Supercomputing (1989)

Refined Languages (Refined Fortran, Refined C, etc.) are extensions of their parent languages in which it is possible to express parallelism, but impossible to create races or deadlocks. Where strictly deterministic behavior is desired, multiple executions of a Refined Fortran program with the same input data can be guaranteed to either compute the same results or terminate with the same run-time errors regardless of differences in scheduling. Where asynchronous behavior is desired, freedom from races can be guaranteed. The Refined Languages approach achieves its goal by extending sequential imperative programming languages with data- (rather than control-) oriented constructs, and by viewing the expression of parallelism in data- (rather than control-) oriented terms. Earlier versions of Refined Fortran are discussed in [1]-[2]; the present work supersedes and extends work reported in these earlier publications.
The Reduced Parzen Classifier
Authors: K. Fukunaga, R. R. Hayes
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (1989)

The Parzen density estimate is known to be an effective tool for estimating the Bayes error, given a set of training samples from the class distributions. An algorithm is developed to select a given number of representative samples whose Parzen density estimate closely matches that of the entire sample set. Using this reduced representative set, a piecewise quadratic classifier which provides nearly optimal performance is designed.
Concurrent constraint programming
Authors: Vijay A. Saraswat, Martin Rinard
Venue: Proceedings of the 17th ACM SIGPLAN-SIGACT symposium on Principles of programming languages (1989)

This paper presents a new and very rich class of (concurrent) programming languages, based on the notion of computing with partial information, and the concomitant notions of consistency and entailment.1 In this framework, computation emerges from the interaction of concurrently executing agents that communicate by placing, checking and instantiating constraints on shared variables. Such a view of computation is interesting in the context of programming languages because of the ability to represent and manipulate partial information about the domain of discourse, in the context of concurrency because of the use of constraints for communication and control, and in the context of AI because of the availability of simple yet powerful mechanisms for controlling inference, and the promise that very rich representational/programming languages, sharing the same set of abstract properties, may be possible. To reflect this view of computation, [Sar89] develops the cc family of languages. We present here one member of the family, cc(&darr;, &rarr;) (pronounced &ldquo;cc with Ask and Choose&rdquo;) which provides the basic operations of blocking Ask and atomic Tell and an algebra of behaviors closed under prefixing, indeterministic choice, interleaving, and hiding, and provides a mutual recursion operator. cc(&darr;, &rarr;) is (intentionally!) very similar to Milner's CCS, but for the radically different underlying concept of communication, which, in fact, provides a general&mdash;and elegant&mdash;alternative approach to &ldquo;value-passing&rdquo; in CCS. At the same time it adequately captures the framework of committed choice concurrent logic programming languages. We present the rules of behavior for cc agents, motivate a notion of &ldquo;visible action&rdquo; for them, and develop the notion of c-trees and reactive congruence analogous to Milner's synchronization trees and observational congruence. We also present an equational characterization of reactive congruence for Finitary cc(&darr;, &rarr;).
Scheduling N jobs on one machine with insert-idle-time constraints
Authors: Yuan-geng Huang, Laveen N. Kanal, Satish K. Tripathi
Venue: Proceedings of the 2nd international conference on Industrial and engineering applications of artificial intelligence and expert systems - Volume 1 (1989)

A new scheduling problem, which is called the insert-idle-time scheduling problem, is proposed which concerns scheduling N jobs on one machine when some of the machine time is unschedulable due to pre-scheduled maintenance time, lunch time or the time devoted to the jobs with higher priority or any other activities. An best-first branch-and-bound algorithm which takes &ldquo;schedule improvement&rdquo; approach is presented and the experimental results are reported.
A delay-based approach for congestion avoidance in interconnected heterogeneous computer networks
Authors: R. Jain
Venue: ACM SIGCOMM Computer Communication Review (1989)

In heterogeneous networks, achieving congestion avoidance is difficult because the congestion feedback from one subnetwork may have no meaning to sources on other subnetworks. We propose using changes in round-trip delay as an implicit feedback. Using a black-box model of the network, we derive an expression for the optimal window as a function of the gradient of the delay-window curve.The problems of selfish optimum and social optimum are also addressed. It is shown that without a careful design, it is possible to get into a race condition during heavy congestion, where each user wants more resources than others, thereby leading to a diverging condition.It is shown that congestion avoidance using round-trip delay is a promising approach. The approach has the advantage that there is absolutely no overhead for the network itself. It is exemplified by a simple scheme. The performance of the scheme is analyzed using a simulation model. The scheme is shown to be efficient, fair, convergent, and adaptive to changes in network configuration.The scheme as described works only for networks which can be modeled with queueing servers with constant service times. Further research is required to extend it for implementation in practical networks. Several directions for future research have been suggested.
Tram: a blackboard architecture for autonomous robots
Authors: Anne Koenig, Elisabeth Crochon
Venue: Proceedings of the 1st international conference on Industrial and engineering applications of artificial intelligence and expert systems - Volume 1 (1988)

In this paper, we present a blackboard model especially dedicated to autonomous robots. The control architecture exploits the ideas of the BB1 model (HAY 85). Our blackboard is non monotonous; this enhances its capabilities. The evolution of the environment is taken into account by our model. We explain the architecture of TRAM : control and structures. We illustrate it by an application in the field of tasks planning for a mobile inspection robot.
Authentication, confidentiality, and integrity extensions to the XNS protocol suite
Authors: R. Housley
Venue: ACM SIGSAC Review (1989)

The Xerox Network Systems (XNS) architecture[1] includes all of the security features found in today's most popular protocol suites. In addition, XNS provides strong authentication at the beginning of each conversation. Authentication is the verification that both entities in a conversation are the ones claimed.[2] The Authentication Protocol[3] provides authentication in such a way that no passwords are ever transmitted on the network.
The PM221 Interconnection Network
Authors: K. Y. Lee, H. Yoon
Venue: IEEE Transactions on Computers (1989)

A scheme based on the standard multiplier recoding technique that enables the use of (5*5) switches for PM2I networks is presented. The connections between switching stages are based on the modified PM2I functions, and are called plus-minus-2/sup 2i/ (PM22I); hence, these networks are called the PM22I networks. Since the number of switching stages in the PM22I networks is one-half of those in the PM2I networks, with a moderate increase in the switch size from (3*3) to (5*5), these networks provide similar design tradeoffs availability by the (2*2) and (4*4) cube networks.
An analytic optimization technique for placement of macro-cells
Authors: A. Herrigel, W. Fichtner
Venue: Proceedings of the 26th ACM/IEEE Design Automation Conference (1989)

This paper discusses the placement of R (rectangular) or L-shaped blocks, such as in macro-cell design. We present a new analytic approach that simultaneously accounts for different criteria (wire length, chip area). We characterize a solution by the associated adjacency graph [1] and derive an optimization technique with an active set method [2]. Results on a test problem are given to prove the performance and feasibility of this technique.
The MARUTI hard real-time operating system
Authors: S. Levi, S. K. Tripathi, S. D. Carson, A. K. Agrawala
Venue: ACM SIGOPS Operating Systems Review (1989)

The MARUTI operating system is designed to support real-time applications on a variety of hardware systems. The kernel supports objects as primitive entities, and provides a communication mechanism that allows transparent distribution in networked systems. Fault tolerance is provided through replication and consistency-control mechanisms. Most importantly, MARUTI supports guaranteed-service scheduling, in which jobs that are accepted by the system are verified to satisfy general time constraints.Guaranteed-service scheduling means that, given a job with a set of service requirements and time constraints, the system automatically verifies the schedulability of each component of the job with respect to the job's constraints and those of other jobs in the system. These time constraints include those that govern interrupt processing, which allows the MARUTI approach to succeed where tess rigorous approaches do not. The result is that MARUTI applications can be executed in a predictable, deterministic fashion.
Four paradigms of information systems development
Authors: Rudy Hirschheim, Heinz K. Klein
Venue: Communications of the ACM (1989)

Developing computer-based information systems necessarily involves making a number of implicit and explicit assumptions. The authors examine four different approaches to information systems development.
An evaluation of vector Fortran 200 generated by Cyber 205 and ETA-10 pre-compilation tools
Authors: R. N. Braswell, M. S. Keech
Venue: Proceedings of the 1988 ACM/IEEE conference on Supercomputing (1988)

Vectorizing pre-compilers such as KAP/205 and VAST-2 complement the efficient use of FORTRAN on the CDC Cyber 205. With the advent of the ETA-10 and its EOS/VSOS environment, the performance of these FORTRAN 200 pre-processors has come under closer scrutiny. The extent or quantity of vectorization that can be achieved has been examined elsewhere with reference to a test set of FORTRAN DO-loops. The quality of the translated code is another issue which deserves attention of course. KAP/205 and VAST-2 will be contrasted in this respect to reveal differences in the vectorized FORTRAN.
The five color concurrency control protocol: non-two-phase locking in general databases
Authors: Partha Dasgupta, Zvi M. Kedem
Venue: ACM Transactions on Database Systems (TODS) (1990)

Concurrency control protocols based on two-phase locking are a popular family of locking protocols that preserve serializability in general (unstructured) database systems. A concurrency control algorithm (for databases with no inherent structure) is presented that is practical, non two-phase, and allows varieties of serializable logs not possible with any commonly known locking schemes. All transactions are required to predeclare the data they intend to read or write. Using this information, the protocol anticipates the existence (or absence) of possible conflicts and hence can allow non-two-phase locking. It is well known that serializability is characterized by acyclicity of the conflict graph representation of interleaved executions. The two-phase locking protocols allow only forward growth of the paths in the graph. The Five Color protocol allows the conflict graph to grow in any direction (avoiding two-phase constraints) and prevents cycles in the graph by maintaining transaction access information in the form of data-item markers. The read and write set information can also be used to provide relative immunity from deadlocks.
The equivalence of the subregion representation and the wall representation for a certain class of rectangular dissections
Authors: S. Kundu
Venue: Communications of the ACM (1988)

A rectangular dissection is a partition of a rectangular space R info n &nge; 1 disjoint rectangles {r1, r2, . . ., rn. Two classes of dissections that are of particular interest in floor-space design and very-large-scale integration (VLSI) space partitioning are called T-plans and T*-plans, where the T*-plans form a subclass of the T-plans. We consider here the subregion tree representation t(D) of a T*-plan D, which describes the successive partitioning operations by which the dissection D is derived. There are four types of partitioning operations in a T*-plan: (1) the horizontal partitioning; (2) the vertical partitioning; (3) the left-spiral partitioning; and (4) the right-spiral partitioning. We show that for a T*-plan the subregion representation and the wall representation are equivalent in the sense that one can be obtained from the other in a unique fashion. The importance of this equivalence property lies in that while the two representations allow different types of design constraints to be represented in a more natural way, these constraints may be converted to the same representation for a more efficient solution of the design problem.