ppxscal/embedding_network huggingface dataset:
DISC++: A C++ based library for object oriented simulation
Authors: E. L. Blair, S. Selvaraj
Venue: Proceedings of the 21st conference on Winter simulation (1989)

The Object Oriented Programming (OOP) paradigm is generating considerable interest and excitement among systems analysts and programmers concerned with a wide range of applications. This paper presents DISC++ (DIscrete event Simulation in C++), a library of routines written in C and C++ which supports the design and programming of simulation models under both the event scheduling and process interaction world-views. DISC++ allows the simulator to construct simpler models from "standard" library objects or design more complex models by deriving specialized and sophisticated objects from the library objects. The OOP philosophy encourages an evolutionary model building process in which code (object classes) is reused and continuously upgraded. A simple example is given to illustrate an application of the process interaction modeling capabilities.
Adaptive semantic snaping&mdash;a technique for semantic feedback at the lexical level
Authors: Scott E. Hudson
Venue: Proceedings of the SIGCHI conference on Human factors in computing systems: Empowering people (1990)

This paper describes the implementation of semantic snapping &mdash; an interaction technique that provides semantic feedback at the lexical level while dragging a graphical object on the screen. Like conventional snapping, or gravity fields, semantic snapping includes a geometric component where objects in close proximity are drawn together or &ldquo;snap&rdquo; into position. However, semantic snapping goes further by allowing non-geometric (semantic) properties of objects to place additional constraints on snapping. Semantic snapping also provides more complex lexical feedback which reflects potential semantic consequences of a snap. This paper motivates the use of semantic snapping and describes how this technique has been implemented in a window-based toolkit. This implementation works in an adaptive manner to provide the best interactive response in situations where semantic tests are very time consuming and strain the limits of acceptable performance.
How some advice fails
Authors: W. C. Hill
Venue: Proceedings of the SIGCHI conference on Human factors in computing systems: Wings for the mind (1989)

Video data for thirty-four cases of advice seeking, giving and following behavior at a graphical computer interface were analyzed in detail. The evidence indicated that clients followed prescriptive advice effectively and efficiently in slightly more than half the cases. For other cases, clients performed twice as many actions as needed in three times as much time and never reached prescribed states. A hypothesis that observed advice following difficulties were correlated with advice abstractness was not supported. Rather, it seems advice did not match well with clients' knowledge of the system in particular isolated details.
Issue spotting in a system for searching interpretation spaces
Authors: T. F. Gordon
Venue: Proceedings of the 2nd international conference on Artificial intelligence and law (1989)

A method for spotting issues is described which uses a system we are developing for searching interpretations spaces and constructing legal arguments. The system is compatible with the legal philosophy known as legal positivism, but does not depend on its notion of clear cases. AI methods applied in the system include an ATMS reason maintenance system, Poole's framework for default reasoning, and an interactive natural deduction theorem prover with a programmable control component for including domain-dependent heuristic knowledge. Our issue spotting method is compared with Gardner's program for identifying the hard and easy issues raised by offer and acceptance law school examination questions.
An object-oriented modelling enviornment
Authors: T. W. Page,  Jr., S. Berson, W. Cheng, R. R. Muntz
Venue: Conference proceedings on Object-oriented programming systems, languages and applications (1989)

Many tools and techniques exist for the modeling and analysis of computer and communication systems. These tools are often complex and tailored to a narrow range of problems. The system analysis task often requires coordinated use of multiple tools and techniques which is not supported by currently available systems. The Tangram project goal is to develop an environment which makes a large set of tools and techniques readily accessible and is easily tailored to specialized applications. This system has been prototyped in an object-oriented extension to Prolog. The impact that these two paradigms, logic and objects, have had on the design is discussed. Several example applications are presented to illustrate the extensibility of the system.
Module algebra
Authors: J. A. Bergstra, J. Heering, P. Klint
Venue: Journal of the ACM (JACM) (1990)

An axiomatic algebraic calculus of modules is given that is based on the operators combination/union, export, renaming, and taking the visible signature. Four different models of module algebra are discussed and compared.
Alpha: An Extension of Relational Algebra to Express a Class of Recursive Queries
Authors: Rakesh Agrawal
Venue: IEEE Transactions on Software Engineering (1988)

An extension of E.F. Codd's relational algebra (1970) with an alpha operator is presented that allows a large class of natural and useful recursive queries to be expressed, and yet has the property of being efficiently implementable. Formally, this class is a superset of linear recursive queries. Intuitively, this class comprises queries that examine transitive relationships between various instances of an entity. It is believed that this class covers many natural and interesting recursive queries. Examples of such queries include determining parts requirements for manufacturing a product, finding the critical path in a project management network, finding the shortest path between two cities, verifying connectivity between two points of a circuit, etc.
Scheduling and binding algorithms for high-level synthesis
Authors: P. G. Paulin, J. P. Knight
Venue: Proceedings of the 26th ACM/IEEE Design Automation Conference (1989)

New algorithms for high-level synthesis are presented. The first performs scheduling under hardware resource constraints and improves on commonly used list scheduling techniques by making use of a global priority function. A new design-space exploration technique, which combines this algorithm with an existing one based on time constraints, is also presented. A second algorithm is used for register and bus allocation to satisfy two criteria: the minimization of interconnect costs as well as the final register (bus) cost. A clique partitioning approach is used where the clique graph is pruned using interconnect affinities between register (bus) pairs. Examples from current literature were chosen to illustrate the algorithms and to compare them with four existing systems.
An intelligent tutor for normal form determination
Authors: Lee A. Becker, Xiaoyi Huang
Venue: ACM SIGCSE Bulletin (1988)

In this paper an intelligent computer-aided instruction system for teaching normal form determination is described. The general architecture of intelligent tutoring systems is also discussed, as are the results of experience using the tool in an undergraduate database course.
Data placement in Bubba
Authors: George Copeland, William Alexander, Ellen Boughter, Tom Keller
Venue: Proceedings of the 1988 ACM SIGMOD international conference on Management of data (1988)

This paper examines the problem of data placement in Bubba, a highly-parallel system for data-intensive applications being developed at MCC. &ldquo;Highly-parallel&rdquo; implies that load balancing is a critical performance issue. &ldquo;Data-intensive&rdquo; means data is so large that operations should be executed where the data resides. As a result, data placement becomes a critical performance issue. In general, determining the optimal placement of data across processing nodes for performance is a difficult problem. We describe our heuristic approach to solving the data placement problem in Bubba. We then present experimental results using a specific workload to provide insight into the problem. Several researchers have argued the benefits of declustering (i e, spreading each base relation over many nodes). We show that as declustering is increased, load balancing continues to improve. However, for transactions involving complex joins, further declustering reduces throughput because of communications, startup and termination overhead. We argue that data placement, especially declustering, in a highly-parallel system must be considered early in the design, so that mechanisms can be included for supporting variable declustering, for minimizing the most significant overheads associated with large-scale declustering, and for gathering the required statistics.
Lightweight remote procedure call
Authors: Brian N. Bershad, Thomas E. Anderson, Edward D. Lazowska, Henry M. Levy
Venue: ACM Transactions on Computer Systems (TOCS) (1990)

Lightweight Remote Procedure Call (LRPC) is a communication facility designed and optimized for communication between protection domains on the same machine. In contemporary small-kernel operating systems, existing RPC systems incur an unnecessarily high cost when used for the type of communication that predominates&mdash;between protection domains on the same machine. This cost leads system designers to coalesce weakly related subsystems into the same protection domain, trading safety for performance. By reducing the overhead of same-machine communication, LRPC encourages both safety and performance. LRPC combines the control transfer and communication model of capability systems with the programming semantics and large-grained protection model of RPC. LRPC achieves a factor-of-three performance improvement over more traditional approaches based on independent threads exchanging messages, reducing the cost of same-machine communication to nearly the lower bound imposed by conventional hardware. LRPC has been integrated into the Taos operating system of the DEC SRC Firefly multiprocessor workstation.
Electron beam activation of floating gate MOS switches a way towards reconfiguration
Authors: P. Girard, M. Valenza, B. Pistoulet
Venue: Microelectronic Engineering (1988)

In this paper, the conditions of E. beam activation of floating gate MOS transistors are analyzed in the low energy primary beam range i.e. 2-6 keV. In order to explain the experimental results, a physical model is developed for the floating gate device. The possibilities for writing erasure cycling are also shown.
Knowledge based simulation of an organization: an agent's behavior in a dynamic environment
Authors: Sigrid Unseld
Venue: ACM SIGSIM Simulation Digest (1988)

MOMo's general purpose "playground" enables the user to test and study the behavior of AI-models (intelligent agents) in a knowledge based simulation environment. Agents and environment form an interacting system: During discrete, event-driven simulation the agents act according to "prototypical images" that reflect their perception of the environment. The actions carried out by the agent are inputs to the environment, causing its state to change. The state of the environment, in turn, defines what the agent may act upon.
Distributed database design: a practical approach and example
Authors: T. J. Teorey
Venue: ACM SIGMOD Record (1989)

A distributed database design problem is presented that involves the development of a global model, a fragmentation, and a data allocation. The student is given a conceptual entity-relationship model for the database and a description of the transactions and a generic network environment. A stepwise solution approach to this problem is shown, based on mean value assumptions about workload and service.
Optimum design of reliable IC power networks having general graph topologies
Authors: S. Chowdhury
Venue: Proceedings of the 26th ACM/IEEE Design Automation Conference (1989)

This paper deals with the problem of sizing integrated-circuit power and ground distribution systems external to the logic modules constituting an integrated circuit. Several constraints associated with the reliability of the power and ground distribution systems are formulated. Algorithms are developed to determine the widths of the power and ground routes so that the area required by the routes is minimized subject to the constraints imposed. Run time results are included.
Secure Broadcasting Using the Secure Lock
Authors: Guang-huei Chiou, Wen-Tsuen Chen
Venue: IEEE Transactions on Software Engineering (1989)

The authors discuss secure broadcasting, effected by means of a secure lock, on broadcast channels, such as satellite, radio, etc. This lock is implemented by using the Chinese Remainder theorem (CRT). The secure lock offers the following advantages: only one copy of the ciphertext is sent; the deciphering operation is efficient; and the number of secret keys held by each user is minimized. Protocols for secure broadcasting using the secure lock, based on the public-key cryptosystem as well as the private-key cryptosystem, are presented.
Acquisition and Representation of 2D and 3D Data from Turbulent Flows and Flames
Authors: Marshall B. Long, Kevin Lyons, Joseph K. Lam
Venue: Computer (1989)

Laser light scattering techniques for making two- and three-dimensional measurements in turbulent flows and flames are outlined, and examples of data representations are shown. Limitations and problems in displaying data are discussed.
Information density of office books
Authors: J. C. McCallum
Venue: ACM SIGOIS Bulletin (1989)

A bookshelf containing 44 books was studied to determine the amount of information found per linear centimeter. The information density was measured for both textual information and pictorial information. The quantity of information found in pictorial form was found to be significantly larger than the textual information when both were represented in uncompressed form. But, when represented in compressed form, the textual and pictorial information were found to be roughly equal.
The 1988 snowbird report: a discipline matures
Authors: David Gries Terry M. Walker, Paul Young
Venue: Communications of the ACM (1989)

With the severe crisis in computing behind us, the field is beginning to shed its preoccupation with its internal affairs. The representation of computing research to the public and to policy makers, was a major issue at Snowbird 88. Since no single entity fills this role, the Computing Research Board plans to fill it.
The reliability of analytic and holistic methods in rating students' computer programs
Authors: David M. Olson
Venue: ACM SIGCSE Bulletin (1988)

The study examined analytic and holistic methods of scoring students's programs. The sample included 30 students in an introductory computer science class. The inter-rater reliabilities for both scoring methods was significant (analytic, r = .66; holistic, r = .73). The correlation between students' holistic and analytic scores on the programs was moderate (r = .66), indicating that the two scoring methods measure different attributes of a student's program.
Self-Synchronizing Communication Protocols
Authors: H. Paul Lin, Harry E. Stovall,  III
Venue: IEEE Transactions on Computers (1989)

An approach called self-synchronizing communication protocols (SSPs) is presented for handling synchronization problems in communication protocols. It is found that many synchronization errors are caused by process collision, which arises when two or more processes simultaneously transmit conflicting messages. A synchronization mechanism that allows processes to detect and resolve collisions during operation is proposed. Advantages of this approach are the simplification and standardization of protocol design. The alternative design of two operating protocols, the CCITT X.21 and a session control protocol in the IBM System Network Architecture (SNA), using SSPs is discussed. It is found that all the errors in a previous version of X.21 result directly from process collision. Making the protocol a suitable candidate for the application of SSPs. The design of an abbreviated version of the SNA session-control protocol using SSPs shows the applicability of the method to protocols with more than two processes and the resulting simplification of the design.
Feedback loops and large subcircuits in the multiprocessor implementation of a relaxation based circuit simulator
Authors: P. Odent, L. Claesen, H. De Man
Venue: Proceedings of the 26th ACM/IEEE Design Automation Conference (1989)

This paper presents several new methods for the efficient parallel simulation of VLSI circuits that contain feedback loops or &ldquo;difficult&rdquo; parts such as arrays, registers and pass-transistor networks. A new parallel algorithm has been developed for the efficient simulation of circuits containing feedback loops. It is based on dataflow scheduling and local relaxation of the loops. For the simulation of large pass-transistor networks a partitioning method is used that is based on signal flow in the elements. Parallel element evaluation and time-segment pipelining are included to increase the performance of the parallel circuit simulator. Simulation tests with actual circuits show a substantial acceleration for the new methods.
Steady-state simulation of queueing processes: survey of problems and solutions
Authors: Krzysztof Pawlikowski
Venue: ACM Computing Surveys (CSUR) (1990)

For years computer-based stochastic simulation has been a commonly used tool in the performance evaluation of various systems. Unfortunately, the results of simulation studies quite often have little credibility, since they are presented without regard to their random nature and the need for proper statistical analysis of simulation output data. This paper discusses the main factors that can affect the accuracy of stochastic simulations designed to give insight into the steady-state behavior of queuing processes. The problems of correctly starting and stopping such simulation experiments to obtain the required statistical accuracy of the results are addressed. In this survey of possible solutions, the emphasis is put on possible applications in the sequential analysis of output data, which adaptively decides about continuing a simulation experiment until the required accuracy of results is reached. A suitable solution for deciding upon the starting point of a steady-state analysis and two techniques for obtaining the final simulation results to a required level of accuracy are presented, together with pseudocode implementations.
Connection caching of traffic adaptive dynamic virtual circuits
Authors: P. Jomer
Venue: ACM SIGCOMM Computer Communication Review (1989)

Local Area Networks may be interconnected using X.25 networks. If only the OSI connectionless network protocol (CLNP) is supported on the LANs, then this same protocol must operate above X.25, using the X.25 service as a virtual data link layer. The intermediate systems in this case must support CLNP packet delivery over X.25 virtual circuits, implementing the ISO 8473/DAD1 subnetwork dependent convergence function to resolve the differences which exist between the OSI connectionless network service and the connection-oriented service offered by the X.25 subnetwork. This means that the main functionality of this subnetwork dependent convergence function is to open virtual circuits on packet demand and to close them when no traffic has occurred for a period of time. This paper describes an algorithm, which calculates such a time period by taking into account the current traffic load, the connection cost and the maintenance cost.
Design complexity measurement and testing
Authors: Thomas J. McCabe, Charles W. Butler
Venue: Communications of the ACM (1989)

System designers can quantify the complexity of a software design by using a trio of finely tuned design metrics.
Measurements and prediction of contention in multiprocessor operating systems with scientific application workloads
Authors: G. E. Bier, M. K. Vernon
Venue: Proceedings of the 2nd international conference on Supercomputing (1988)

This paper examines the effect of contention for a single shared semaphore protecting critical regions in a multiprocessor operating system on system performance as the number of processors increases. A simple queueing model is used to make predictions as a function of the expected demand for the semaphore by each processor. Measurements are then presented for 2 and 4 processor configurations of the CRAY X-MP running an experimental version of UNICOS. The measurements indicate that demand is highly dependent on the workload, and that contention can be somewhat higher than predicted by the model due to process scheduling effects and request interdependencies. One interesting point which is revealed in the measurement results, is that the UNIX scheduler gives preferential treatment to jobs that make frequent requests for the semaphore.
Conflict management in a source version management system
Authors: B. Mack-Crane, A. Pal
Venue: ACM SIGSOFT Software Engineering Notes (1989)

To support concurrent development a source version management system must support multiple programmers concurrently accessing shared source code, while maintaining the integrity of the source database. This problem is similar to the problem of concurrency control in database systems, but has a few significant differences. This leads us to view the possible solutions as variations on database transaction management and concurrency control. In particular we consider the possibility of letting transactions interact and managing the conflicts which result.1
Performance Analysis of Multibuffered Packet-Switching Networks in Multiprocessor Systems
Authors: Hyunsoo Yoon
Venue: IEEE Transactions on Computers (1990)

An analytic model and analytic results for the performance of multibuffered packet-switching interconnection networks in multiprocessor systems are presented. The performance of single-buffered delta networks is first modeled using the state transition diagram of a buffer. The model is then extended to account for multiple buffers. The analytic results for multibuffered delta networks are compared to simulation results. The performance of multibuffered data manipulator networks is analyzed to demonstrate the generality of the model.
Measuring the scalability of parallel computer systems
Authors: J. R. Zirbas, D. J. Reble, R. E. vanKooten
Venue: Proceedings of the 1989 ACM/IEEE conference on Supercomputing (1989)

This paper discusses scalability and outlines a specific approach to measuring the scalability of parallel computer systems. The relationship between scalability and speedup is described. It is shown that a parallel system is scalable for a given algorithm if and only if its speedup is unbounded. A technique is proposed that can be used to help determine whether a candidate model is correct, that is, whether it adequately approximates the system's scalability. Experimental results illustrate this technique for both a poorly scalable and a very scalable system.
An approach to the recursive retrieval problem in the relational database
Authors: F.-Y. Kuo, J. Tillquist
Venue: Communications of the ACM (1989)

The host query language often impairs data retrieval in recursive database structures. Functional extensions to QUEL are explored in order to simplify the user interface.